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Keratosis pilaris is a common genetic skin condition which appears as rough, bumpy, sometimes red skin most often found on upper arms, thighs, and cheeks. These bumps are due to a buildup of keratin, a hard protective protein found in skin, hair, and nails. This built up keratin forms a plug which blocks the opening of hair follicles. When these plugs, or bumps, become irritated it causes redness.
Keratosis pilaris usually presents in childhood, often at its worst during puberty, but can continue into adulthood. The condition usually improves in warmer weather, while dry weather seems to exacerbate symptoms.
There is no known cure for Keratosis pilaris, though steps can be taken to keep minimize bumps and redness.
| 3.394687 |
I recently saw the movie "Amazing Grace," about the end of the slave trade in England. How does libertarianism respond to the American Civil War and the Civil rights movement? In both of them, government action was used to enhance freedom.
Government action made slavery possible, and kept it possible -- and the government only backtracked when the citizenry objected.
For example, prior to the Civil War, slavery was legal and enforced by governments of both North and South. Slaves who escaped to the North were returned -- by law -- to their Southern "owners." It was against the law in the North to help slaves escape. To fight slavery it was necessary for freedom lovers to fight the law.
Members of the Underground Railroad, who tried to get the escaped slaves to Canada where they couldn't be extradited, were routinely hauled into court. Courageous individuals serving on the juries refused to convict. (Juries have the constitutionally-granted power to "nullify" laws that they believe to be unjust; to learn more, see the Fully Informed Jury Association)
Lincoln's Emancipation Proclamation was not issued until the Civil War had been underway for years, and it only "emancipated" slaves in states that had joined the Confederacy. Towards the end of the Civil War, indignant abolitionists, supported by President Lincoln, lobbied for an amendment to the Constitution to free the blacks still enslaved in Northern states.
Although Southern states didn't vote on this amendment, it still did not pass easily.
Similarly, government power enforced, and often mandated, compulsory racial segregation in the South in the first half of the twentieth century. For example, economist Thomas Sowell points out that racially segregated seating on public transportation, far from being a traditional Southern policy, only began in the late 19th and early 20th centuries -- and it was government that created the problem.
Writes Dr. Sowell:
"Many, if not most, municipal transit systems were privately owned in the 19th century and the private owners of these systems had no incentive to segregate the races.
"These owners may have been racists themselves but they were in business to make a profit -- and you don't make a profit by alienating a lot of your customers. There was not enough market demand for Jim Crow seating on municipal transit to bring it about.
"... Private owners of streetcar, bus, and railroad companies in the South lobbied against the Jim Crow laws while these laws were being written, challenged them in the courts after the laws were passed, and then dragged their feet in enforcing those laws after they were upheld by the courts.
"These tactics delayed the enforcement of Jim Crow seating laws for years in some places. Then company employees began to be arrested for not enforcing such laws and at least one president of a streetcar company was threatened with jail if he didn't comply.
(Dr. Sowell discusses this in greater detail in his book Preferential Policies, An International Perspective, 1990, pp.20-21.]
This is not to say that these transportation company owners were not racists, or were champions of black freedom. They simply wanted to make money. And free markets make racial discrimination extraordinarily, even prohibitively, expensive.
Because of such government-mandated discrimination, the modern Civil Rights movement was pioneered by individuals such as Rosa Parks and Martin Luther King, who practiced peaceful civil disobedience. Without the courageous sacrifices of such people, it's unlikely that Congress would have been inspired (shamed?) into action.
Dr. Ruwart's outstanding books Healing Our World and Short Answers to the Tough Questions are available at the Advocates Liberty Store.
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Obtaining Informed Consent from human subjects is a necessary and important part of research that reflects the principle of respect for persons. Informed consent assures that prospective human subjects will understand the nature of the research and can knowledgeably and voluntarily decide whether or not to participate.
The Informed Consent process should be tailored to each individual project; what is appropriate and approved for one project may not be appropriate or approved for another. When developing Informed Consent procedures and forms Investigators should keep in mind the prospective participant population, the risk involved in the research, the sensitivity of the research, and the research procedures.
The IRB has developed the guidance documents below to help Investigators develop appropriate Informed Consent procedures and forms.
- General Information about Informed Consent
- Information regarding Waiving Informed Consent or Required Elements of Informed Consent
- Methods for Obtaining Documentation of Informed Consent
- Information regarding Waiving Documentation of Informed Consent
- Information regarding Informed Consent with Minors or individuals who are Mentally Impaired
- Consent Form Template
- Policy for Translated Informed Consent Forms (for Non-English Consent Forms)
Things to Keep in Mind when Developing Informed Consent Procedures for your Project:
Regarding the Prospective Participant Population:
Will prospective participants be old enough to provide legal consent?
If participants will not be old enough to provide legal consent, Investigators generally needs to obtain consent from a parent/guardian as well as assent from the minor. For more information, please review the IRB's Guidance on Informed Consent for Research with Minors.
In some cases, the IRB may approve requests to Waive Informed Consent of parents for research with minors. In order to Waive the Informed Consent of parents, Investigators would need to show that their research qualifies for a Waiver. The criteria to apply for a waiver are on the Request for a Waiver of Informed Consent or Elements of Informed Consent form.
Will prospective participants be literate?
Will prospective participants be able to speak and read English? Will they be able to speak and read another language?
What reading comprehension level do you expect prospective participants will have?
If you are conducting research with another cultural group, is it culturally appropriate to ask participants to read and sign informed consent forms?
Information that should be included in the IRB application regarding Informed Consent procedures
- When will participants be given the Informed Consent information?
- How will participants receive Informed Consent information?
- Will the Investigator be reviewing the consent information with participants, or will participants review it on their own?
- Who from the research team will administer the Informed Consent process (e.g. the Principal Investigator, a research assistant)?
- Will the consent process be administered separately to each individual or in a group with other participants?
- How much time will prospective participants have to review the information before they are asked to decide if they will participate in the research?
- How will participants indicate they consent to participate?
- If prospective participants will be signing Informed Consent Forms, how will they return the forms to the Investigator?
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There are a couple of different ways to execute commands or run programs on a remote machine and have the output, be it text or graphics, sent to your workstation. The connections can be secure or insecure. While it is of course advised to use secure connections instead of transporting your password over the network unencrypted, we will discuss some practical applications of the older (unsafe) mechanisms, as they are still useful in a modern networked environment, such as for troubleshooting or running exotic programs.
The rlogin and rsh commands for remote login and remote execution of commands are inherited from UNIX. While seldom used because they are blatantly insecure, they still come with almost every Linux distribution for backward compatibility with UNIX programs.
Telnet, on the other hand, is still commonly used, often by system and network administrators. Telnet is one of the most powerful tools for remote access to files and remote administration, allowing connections from anywhere on the Internet. Combined with an X server, remote graphical applications can be displayed locally. There is no difference between working on the local machine and using the remote machine.
Because the entire connection is unencrypted, allowing telnet connections involves taking high security risks. For normal remote execution of programs, Secure SHell or ssh is advised. We will discuss the secure method later in this section.
However, telnet is still used in many cases. Below are some examples in which a mail server and a web server are tested for replies:
Checking that a mail server works:
[jimmy@blob ~] telnet mailserver 25 Trying 192.168.42.1... Connected to mailserver. Escape character is '^]'. 220 m1.some.net ESMTP Sendmail 8.11.6/8.11.6; 200302281626 ehlo some.net 250-m1.some.net Hello blob.some.net [10.0.0.1], pleased to meet you 250-ENHANCEDSTATUSCODES 250-8BITMIME 250-SIZE 250-DSN 250-ONEX 250-ETRN 250-XUSR 250 HELP mail from: [email protected] 250 2.1.0 [email protected]... Sender ok rcpt to: [email protected] 250 2.1.5 [email protected]... Recipient ok data 354 Enter mail, end with "." on a line by itself test . 250 2.0.0 g2MA1R619237 Message accepted for delivery quit 221 2.0.0 m1.some.net closing connection Connection closed by foreign host.
Checking that a web server answers to basic requests:
[jimmy@blob ~] telnet www.some.net 80 Trying 188.8.131.52... Connected to www.some.net. Escape character is '^]'. HEAD / ;HTTP/1.1 HTTP/1.1 200 OK Date: Fri, 22 Mar 2002 10:05:14 GMT Server: Apache/1.3.22 (UNIX) (Red-Hat/Linux) mod_ssl/2.8.5 OpenSSL/0.9.6 DAV/1.0.2 PHP/4.0.6 mod_perl/1.24_01 Last-Modified: Fri, 04 Jan 2002 08:21:00 GMT ETag: "70061-68-3c3565ec" Accept-Ranges: bytes Content-Length: 104 Connection: close Content-Type: text/html Connection closed by foreign host. [jimmy@blob ~]
This is perfectly safe, because you never have to give a username and/or password for getting the data you want, so nobody can snoop that important information off the cable.
As we already explained in Chapter 7 (see Section 7.3.3), the X Window system comes with an X server which serves graphics to clients that need a display.
It is important to realize the distinction between the X server and the X client application(s). The X server controls the display directly and is responsible for all input and output via keyboard, mouse and display. The X client, on the other hand, does not access the input and output devices directly. It communicates with the X server which handles input and output. It is the X client which does the real work, like computing values, running applications and so forth. The X server only opens windows to handle input and output for the specified client.
In normal operation (graphical mode), every Linux workstation is an X server to itself, even if it only runs client applications. All the applications you are running (for example, Gimp, a terminal window, your browser, your office application, your CD playing tool, and so on) are clients to your X server. Server and client are running on the same machine in this case.
This client/server nature of the X system makes it an ideal environment for remote execution of applications and programs. Because the process is actually being executed on the remote machine, very little CPU power is needed on the local host. Such machines, purely acting as servers for X, are called X terminals and were once very popular. More information may be found in the Remote X applications mini-HOWTO.
If you would want to use telnet to display graphical applications running on a remote machine, you first need to give the remote machine access to your display (to your X server!) using the xhost command, by typing a command similar to the one below in a terminal window on your local machine:
davy:~> xhost +remote.machine.com
After that, connect to the remote host and tell it to display graphics on the local machine by setting the environment variable DISPLAY:
[davy@remote ~] export DISPLAY="local.host.com:0.0"
After completing this step, any application started in this terminal window will be displayed on your local desktop, using remote resources for computing, but your local graphical resources (your X server) for displaying the application.
This procedure assumes that you have some sort of X server (XFree86, X.org, Exceed, Cygwin) already set up on the machine where you want to display images. The architecture and operating system of the client machine are not important as long as they allow you to run an X server on it.
Mind that displaying a terminal window from the remote machine is also considered to be a display of an image.
Most UNIX and Linux systems now run Secure SHell in order to leave out the security risks that came with telnet. Most Linux systems will run a version of OpenSSH, an Open Source implementation of the SSH protocol, providing secure encrypted communications between untrusted hosts over an untrusted network. In the standard setup X connections are automatically forwarded, but arbitrary TCP/IP ports may also be forwarded using a secure channel.
The ssh client connects and logs into the specified host name. The user must provide his identity to the remote machine as specified in the sshd_config file, which can usually be found in /etc/ssh. The configuration file is rather self-explanatory and by defaults enables most common features. Should you need help, you can find it in the sshd man pages.
When the user's identity has been accepted by the server, the server either executes the given command, or logs into the machine and gives the user a normal shell on the remote machine. All communication with the remote command or shell will be automatically encrypted.
The session terminates when the command or shell on the remote machine exits and all X11 and TCP/IP connections have been closed.
When connecting to a host for the first time, using any of the programs that are included in the SSH collection, you need to establish the authenticity of that host and acknowledge that you want to connect:
lenny ~> ssh blob The authenticity of host 'blob (10.0.0.1)' can't be established. RSA fingerprint is 18:30:50:46:ac:98:3c:93:1a:56:35:09:8d:97:e3:1d. Are you sure you want to continue connecting (yes/no)? yes Warning: Permanently added 'blob,192.168.30.2' (RSA) to the list of known hosts. Last login: Sat Dec 28 13:29:19 2002 from octarine This space for rent. lenny is in ~
It is important that you type "yes", in three characters, not just "y". This edits your ~/.ssh/known_hosts file, see Section 10.4.4.3.
If you just want to check something on a remote machine and then get your prompt back on the local host, you can give the commands that you want to execute remotely as arguments to ssh:
lenny ~> ssh blob who jenny@blob's password: root tty2 Jul 24 07:19 lena tty3 Jul 23 22:24 lena 0: Jul 25 22:03 lenny ~> uname -n magrat.example.com
If the X11Forwarding entry is set to yes on the target machine and the user is using X applications, the DISPLAY environment variable is set, the connection to the X11 display is automatically forwarded to the remote side in such a way that any X11 programs started from the shell will go through the encrypted channel, and the connection to the real X server will be made from the local machine. The user should not manually set DISPLAY. Forwarding of X11 connections can be configured on the command line or in the sshd configuration file.
The value for DISPLAY set by ssh will point to the server machine, but with a display number greater than zero. This is normal, and happens because ssh creates a proxy X server on the server machine (that runs the X client application) for forwarding the connections over the encrypted channel.
This is all done automatically, so when you type in the name of a graphical application, it is displayed on your local machine and not on the remote host. We use xclock in the example, since it is a small program which is generally installed and ideal for testing:
SSH will also automatically set up Xauthority data on the server machine. For this purpose, it will generate a random authorization cookie, store it in Xauthority on the server, and verify that any forwarded connections carry this cookie and replace it by the real cookie when the connection is opened. The real authentication cookie is never sent to the server machine (and no cookies are sent in the plain).
Forwarding of arbitrary TCP/IP connections over the secure channel can be specified either on the command line or in a configuration file.
|The X server|
This procedure assumes that you have a running X server on the client where you want to display the application from the remote host. The client may be of different architecture and operating system than the remote host, as long as it can run an X server, such as Cygwin (which implements an X.org server for MS Windows clients and others) or Exceed, it should be possible to set up a remote connection with any Linux or UNIX machine.
The ssh client/server system automatically maintains and checks a database containing identifications for all hosts it has ever been used with. Host keys are stored in $HOME/.ssh/known_hosts in the user's home directory. Additionally, the file /etc/ssh/ssh_known_hosts is automatically checked for known hosts. Any new hosts are automatically added to the user's file. If a host's identification ever changes, ssh warns about this and disables password authentication to prevent a Trojan horse from getting the user's password. Another purpose of this mechanism is to prevent man-in-the-middle attacks which could otherwise be used to circumvent the encryption. In environments where high security is needed, sshd can even be configured to prevent logins to machines whose host keys have changed or are unknown.
The SSH suite provides scp as a secure alternative to the rcp command that used to be popular when only rsh existed. scp uses ssh for data transfer, uses the same authentication and provides the same security as ssh. Unlike rcp, scp will ask for passwords or passphrases if they are needed for authentication:
lenny /var/tmp> scp Schedule.sdc.gz blob:/var/tmp/ lenny@blob's password: Schedule.sdc.gz 100% |*****************************| 100 KB 00:00 lenny /var/tmp>
Any file name may contain a host and user specification to indicate that the file is to be copied to/from that host. Copies between two remote hosts are permitted. See the Info pages for more information.
If you would rather use an FTP-like interface, use sftp:
lenny /var/tmp> sftp blob Connecting to blob... lenny@blob's password: sftp> cd /var/tmp sftp> get Sch* Fetching /var/tmp/Schedule.sdc.gz to Schedule.sdc.gz sftp> bye lenny /var/tmp>
|Secure copy or FTP GUIs|
Don't feel comfortable with the command line yet? Try Konqueror's capabilities for secure remote copy, or install Putty.
The ssh-keygen command generates, manages and converts authentication keys for ssh. It can create RSA keys for use by SSH protocol version 1 and RSA or DSA keys for use by SSH protocol version 2.
Normally each user wishing to use SSH with RSA or DSA authentication runs this once to create the authentication key in $HOME/.ssh/identity, id_dsa or id_rsa. Additionally, the system administrator may use this to generate host keys for the system.
Normally this program generates the key and asks for a file in which to store the private key. The public key is stored in a file with the same name but .pub appended. The program also asks for a passphrase. The passphrase may be empty to indicate no passphrase (host keys must have an empty passphrase), or it may be a string of arbitrary length.
There is no way to recover a lost passphrase. If the passphrase is lost or forgotten, a new key must be generated and copied to the corresponding public keys.
We will study SSH keys in the exercises. All information can be found in the man or Info pages.
VNC or Virtual Network Computing is in fact a remote display system which allows viewing a desktop environment not only on the local machine on which it is running, but from anywhere on the Internet and from a wide variety of machines and architectures, including MS Windows and several UNIX distributions. You could, for example, run MS Word on a Windows NT machine and display the output on your Linux desktop. VNC provides servers as well as clients, so the opposite also works and it may thus be used to display Linux programs on Windows clients. VNC is probably the easiest way to have X connections on a PC. The following features make VNC different from a normal X server or commercial implementations:
No state is stored at the viewer side: you can leave your desk and resume from another machine, continuing where you left. When you are running a PC X server, and the PC crashes or is restarted, all remote applications that you were running will die. With VNC, they keep on running.
It is small and simple, no installation needed, can be run from a floppy if needed.
Platform independent with the Java client, runs on virtually everything that supports X.
Sharable: one desktop may be displayed on multiple viewers.
More information can be found in the VNC client man pages (man vncviewer) or on the VNC website.
In order to ease management of MS Windows hosts, recent Linux distributions support the Remote Desktop Protocol (RDP), which is implemented in the rdesktop client. The protocol is used in a number of Microsoft products, including Windows NT Terminal Server, Windows 2000 Server, Windows XP and Windows 2003 Server.
Surprise your friends (or management) with the fullscreen mode, multiple types of keyboard layouts and single application mode, just like the real thing. The man rdesktop manual provides more information. The project's homepage is at http://www.rdesktop.org/.
Cygwin provides substantial UNIX functionality on MS Windows systems. Apart from providing UNIX command line tools and graphical applications, it can also be used to display a Linux desktop on an MS Windows machine, using remote X. From a Cygwin Bash shell, type the command
/usr/X11R6/bin/XWin.exe -query your_linux_machine_name_or_IP
The connection is by default denied. You need to change the X Display Manager (XDM) configuration and possibly the X Font Server (XFS) configuration to enable this type of connection, where you get a login screen on the remote machine. Depending on your desktop manager (Gnome, KDE, other), you might have to change some configurations there, too.
If you do not need to display the entire desktop, you can use SSH in Cygwin, just like explained in Section 10.4.4. without all the fuss of editing configuration files.
| 3.159151 |
Programmatic Support and Technical Assistance Branch
Maryland's Early Intervention and Preschool Special Education (Birth through 5)
The supports and services provided through early intervention and preschool special education can help infants, toddlers and children and their families make the powerful connections to improve their ability to learn and play. These services are all based on the federal Individuals with Disabilities Act (IDEA), which ensure that all children with disabilities have the opportunity to receive a free and appropriate education (FAPE) to support their unique development and learning needs. The evidence has shown that one of the most effective ways to achieve this mandate is to reach children with developmental delays and disabilities when they are very young. Early intervention and education helps to open the window of opportunity for young children with disabilities and their families.
| 3.150773 |
Common Snapping Turtle
Common Snapping Turtle
RANGE:the Americas, from southern Canada to Ecuador
HABITAT:inland and coastal waterways including ponds, lakes, marshes, swamps, slow-moving rivers
DIET: OMNIVOREsmall animals of almost any type, aquatic vegetation, and carrion
LIFESPAN:30-40 years on average
OFFSPRING:20-40 eggs per clutch, on average
LENGTH:carapace (top shell): up to 20 inches
WEIGHT:20-30 lbs on avg., but 40-60 pounders are not unusual
“Where I live”
Snapping turtles are common and widespread from southern Canada to Ecuador, and across most of the United States. They inhabit inland and coastal waters of many types, but seem to prefer slow-moving bodies of water with soft mud bottoms and plenty of submerged and emergent plants.
“How I live there”
Common snapping turtles are one of the largest species of freshwater and salt-marsh turtle in North America. They are active year-round in the southern parts of their range, and overwinter in the northern parts of their range by burying themselves in mud at the bottom of a pond or lake. They tolerate cold water well, though, and remain inactive for only a short period of time.
Snapping turtles spend most of their time in water rather than on land. Defensively and otherwise, they are well designed for life on the bottom. They have large carapaces (top shells) that protect them from attack from above. They have small plastrons (bottom shells), but few predators can or would attack them from below.
Like other turtles and all other reptiles, snapping turtles need to bask in the sun in order to warm themselves and maintain an optimal internal body temperature. However, snapping turtles rarely come out of the water to bask. You might see one on a log from time to time, but you are more likely to see one floating at the water’s surface with most of its carapace and snout showing.
Snapping turtles are most active at dawn and dusk, and this is when they do most of their feeding. They are opportunistic omnivores that eat just about anything that presents itself, including fish, frogs, tadpoles, salamanders, insects, aquatic plants, snails, leeches, worms, snakes, bird eggs and nestlings, small mammals, and carrion. They grab their food with a quick snapping motion.
“Making my mark”
The snapping turtle’s ferocious reputation matches its ferocious appearance but is only somewhat deserved. In the water, snapping turtles will quickly swim away from any human disturbance. On land, they are more vulnerable and therefore more defensive. They will react to any threat aggressively.
Be well aware that snapping turtles are dangerous to handle. They can strike quickly forwards, sideways, or backwards (with their heads upside down), and their necks can stretch 2/3 the length of their carapaces!
Snapping turtles breed during the spring and early summer months. During breeding season, males may battle each other, and their scuffles can last upwards of an hour. Males fight each other somewhat like sumo wrestlers, banging up against each other with bodies upright, grabbing hold of each other in a tight grip with their plastrons pressed together, and rolling over and over in the water. There can be quite a lot of biting, kicking, and scratching, but rarely do the battles end in serious injury or death.
After mating, females will leave their aquatic homes and come onto land to search for suitable nesting sites. They may locate their nests near the shoreline of a pond or lake, or further away from water, in an open field, gravel bank, railroad bed, or sand dune. A female will dig a nest, deposit her eggs (which are perfectly round and about the size of a Ping-Pong ball), and cover them by scooping sand or dirt into the nest. Immediately after depositing her eggs, she will head back to the pond or water source from which she came.
Many, if not most, nests are ransacked by predators. Those eggs that survive will hatch in late summer, and the temperature at which they were incubated determines the sex of the hatchlings. Baby snapping turtles are about one inch long at hatching, with tails about the same length. Depending on the group, the babies will either emerge within a few days and head straight for water or remain in their nest through the winter. Once hatchlings reach water, they stay in the shallows clinging to underwater vegetation until they become stronger swimmers.
“What eats me”
Snapping turtle eggs and babies are extremely vulnerable to predation. Skunks, foxes, raccoons, and mink frequently raid nests and eat eggs. Hatchlings are also eaten by a variety of predators, including herons, hawks, alligators, large fish, raccoons, snakes, and larger turtles.
Adult snapping turtles have fewer predators, but these include alligators, otters, coyotes, bears, and most significantly man.
A threatened snapping turtle will turn to face its attacker head-on. It will hiss and, if unable to escape, deliver a very strong bite.
Snapping turtles are common and widespread throughout their range.
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Catholic social teaching, sometimes referred to as the social doctrine of the Church, is a body of official Church teachings on the social order, composed of papal statements and conciliar or synodal documents. These social teachings originated with Pope Leo XIII and continue to the present.
The Catholic social tradition, however, is much older than this body of teachings, and is rooted in the Hebrew and Christian Scriptures as well as in the patristic writings, which go back as far as the fifth century. This tradition provides a framework and an intellectual legacy from which the more recent (dating from the nineteenth century) social teachings draw. This tradition is a point of reference against which the social teachings are tested, even as the latter develop beyond the tradition by applying it to new issues and questions.
Catholic social teaching is rooted in the dignity of the human person as created in the image of God, and the human rights and duties that protect and enhance this dignity. Catholic social teaching is also concerned with the social nature of the human person, the concept of the common good, the relationship between society and the state, the theory of justice, an "option for the poor," and the concepts of subsidiarity and solidarity.
Campus Ministry | Swartz Center for Spiritual Life | [email protected] | (570) 961-4723
| 3.185661 |
(Bacterial Arthritis; Infectious Arthritis; Pyogenic Arthritis)
Septic arthritis is a serious infection of the joints caused by bacteria. This infection causes the joint to be filled with pus cells. These pus cells release substances directed against the bacteria. However, this action can damage the joint structures, bone, and surrounding cartilage.
This condition should be treated as a medical emergency. If left untreated, it causes loss of function in the affected joint. It can lead to septic shock , a potentially fatal condition. With early treatment, recovery is usually good.
Copyright © Nucleus Medical Media, Inc.
Septic arthritis develops when bacteria spreads from the source of infection through the bloodstream to a joint. It can result from:
- Infection due to an injection
- Other infections
Septic arthritis can also be caused from injury or trauma. It can result from:
- A penetration wound
- An injury that affects the joint
Septic arthritis can strike at any age. But, it occurs most often in children aged three and younger. In infants, the hip is a frequent site of infection. In toddlers, it is the shoulders, knees, and hips. In children, the most common bacterial causes are:
- Staphylococcus aureus ( staph infection )
- Streptococcus species (eg, group B strep infection)
- Streptococcus pneumoniae (a common bacterial cause of pneumonia )
Septic arthritis rarely occurs from early childhood through adolescence. After that, its occurs more often. In adults, it most commonly affects weight-bearing joints, such as the knees. In adults, the most common causes are:
- Staphylococcus aureus
- Neisseria gonorrhoeae (the bacteria that causes gonorrhea)
The following factors increase your chance of developing septic arthritis. If you have any of these risk factors, tell your doctor:
- Diseases that weaken the immune system, such as HIV , or taking drugs that suppress immunity
- A history of joint problems or having other types of arthritis , gout , or lupus
- A history of IV drug use
- Chronic illnesses (eg, anemia , diabetes , sickle cell , kidney failure )
- Joint replacement or organ transplant surgery
- Recent injections (eg, cortisone or hyaluronic acid)
- Skin conditions (eg, psoriasis , eczema )
If you experience any of these symptoms do not assume it is because of septic arthritis. These symptoms may be caused by other, less serious conditions.
Newborn or infants
- Crying when a joint is moved (eg, during a diaper change)
- Immobility of the limb of a joint
- Swelling and redness
- Persistent crying for any reason
Children and adults
- Intense joint pain
- Joint swelling and redness
- Immobility of a joint or its limb
Your doctor will ask about you or your child’s symptoms and medical history. A physical exam will be done. Your doctor may refer you to a specialist.
Your doctor may need to test your bodily fluids. This can be done with:
- Synovial fluid (fluid that lubricates the joint) testing
- Blood tests
Your doctor may need pictures of your joints. This can be done with x-rays.
Antibiotic therapy is started as soon as a diagnosis is made. In the beginning, antibiotics are given by IV. This is to ensure that the infected joint receives medicine to kill the bacteria. The specific medicines used depend on the type of bacteria that is causing the infection. The remaining course of antibiotics may be given orally.
Fluid may be removed from the joint to reduce the likelihood of joint damage. This may be done either by placing a needle in the joint or through surgery.
Rest, preventing the joint from moving, and warm compresses may be used to manage pain. Physical therapy or exercises may also speed recovery.
If you are diagnosed with septic arthritis, follow your doctor's instructions .
To help reduce your chance of getting septic arthritis, get prompt treatment of infections that could lead to septic arthritis.
Last reviewed November 2012 by Michael Woods, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
| 3.576917 |
Definition of Miscarriage, multiple
Miscarriage, multiple: More than one miscarriage for a woman. In multiple miscarriages, there is about a 5 percent chance that one member of the couple is carrying a chromosome translocation responsible for the miscarriages. Other causes of multiple miscarriage include Rh incompatibility, continuing exposure to teratogens (agents that can injure the fetus), and physical problems in the mother that make it difficult for her to carry a fetus to term.
Last Editorial Review: 6/14/2012
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The striped textiles of Yemen were famous throughout the Islamic world. They were made in the resist‑dyed ikat technique to form patterns of arrowheads and diamonds. Inscriptions on Yemeni ikats are often painted, as in this example. Such inscribed textiles were called tiraz, from the Persian word meaning "embroidery." They were produced in tiraz workshops under royal control. Such textiles usually bore inscriptions naming the current ruler or caliph to whom the recipient owed loyalty. Tiraz textiles were presented by rulers as robes of honor at formal ceremonies.
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Definition of orc
n. - The grampus. 2
The word "orc" uses 3 letters: C O R.
Words formed by adding one letter before or after orc (in bold), or to cor in any order:
a - arco orca c - croc d - cord e - cero core f - corf i - coir k - cork rock m - corm n - corn p - crop s - cors orcs rocs t - torc w - crow y - cory
Shorter words found within orc:
All words formed from orc by changing one letter
Browse words starting with orc by next letter
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This project just makes a wireless fm microphone which looks very simple in its structure. It is a useful device in our day-today life. A wireless microphone, as the name implies, is a microphone without a physical cable connecting it directly to the sound recording or amplifying equipment with which it is associated. More commonly known as a Radio Microphone, there are many different standards, frequencies and transmission technologies used to replace the microphone's cable connection and make it into a wireless microphone. They can transmit, for example, in radio waves using UHF or VHF frequencies, FM, AM, or various digital modulation schemes. Some low cost models use infrared light. Infrared microphones require a direct line of sight between the microphone and the receiver, while costlier radio frequency models do not. Some models operate on a single fixed frequency, but the more advanced models operate on a user selectable frequency to avoid interference and allow the use of several microphones at the same time. It can be used in seminar halls, class rooms, for a school or college radio etc. One such piece costs 100-300 rupees in the market. The coming sections give the entire idea of making a miniature wireless microphone. We hope that you will find this quite interesting as you go through this particular project.
2. BLOCK DIAGRAM AND ITS DESCRIPTION
Figure 1: Block Diagram
Above diagram shows the block diagram of the simple wireless fm microphone. It consists of simple audio amplifier, modulated tuned amplifier & a condenser mic. Here a microphone (condenser) captures the audio signal and a simple audio amplifier amplifies this signal before the modulation is done. A modulated tuned amplifier modulates the signal with self generated carrier frequency. The carrier frequency can be varied by changing the capacitor and inductor value in the tank circuit. Then the modulated signal is fed to the antenna. As a trimmer capacitor is used in the L-C circuit, we can vary the transmitting frequency anywhere in the whole FM band.
4. COMPONENTS DESCRIPTION
A resistor is a two terminal electronic component that opposes an electric current by producing a voltage drop between its terminals in its terminals in proportion to the current, that is in accordance with Ohm's law: V=IR. The electrical resistance R is equals to the voltage drop V across the resistor divided by the current / through the resistor. Resistors are used as part of electrical networks and electronic circuits.
An electrical signal can be amplified by using transistors that allows a small current or voltage to control the flow of a much larger current. In analog circuit transistors are used in oscillator, amplifier and linear regulated power supply. Transistors are also used in digital circuits where they function as electronic switches. Digital circuits include logic gates, RAM and micro processors. Here we use 2N3904 transistor. It is a common NPN bipolar junction transistor. It is used for general purpose low power amplifying and switching applications. It is designed for low current and power, medium voltage and can operate at moderately high speed. This transistor is of low cost and is widely available. When looking at the flat side,with the base pointed downwards, the three wires emerging from the base are, left to right, the emitter ,base and collector leads.
The inductor used in the circuit is a handmade coil using 22 SWG (Standard Wire Gauge) enameled copper wire. The length, inner diameter, number of turns etc are the important parameters to be considered while making the inductor. Then only the inductor resonates in the 88-108 band FM frequency. For this circuit, the coil radius was selected as 0.26 inches (outer diameter) and 0.13 inner diameter. Coil can be wound around a screw driver (with same diameter) to get a 5 turn coil of 0.2
inch long. Remove the coil from the screw driver and use the 5 turn Air core coil. Remove the enamel from the tips and solder close to the transistor.
The inductance of the coil can be calculated using the formula :
L =n2r2/ (9r + 10 x)
Where r is the inner radius of the coil, x is the length of the coil and n, number of turns. The resulting value is in Micro Henry.
An inductor is just a coil of wire and you need to wind one for this circuit. An inductor is characterized by its length, radius and the number of turns of wire in the coil. Magnet wire (Radio Shack part 278-1345) was used to build the inductor but you can use standard solid strand 22 AWG gauge copper wire. Some on-line and printed articles describe winding the wire around a pencil. Unfortunately, pencils come in different diameters and hence a McDonald’s soda straw was used; the yellow-red-white striped straw, found in every McDonalds in the world, is the same size. The straw’s radius is exactly 0.1325 inches (diameter = 0.2650 inches) and 1/4 inches was snipped off the straw.
4. 4 CONDENSER MIC
The condenser MIC is used to pick up the sound signals. The diaphragm inside the MIC vibrates according to the air pressure changes and generates AC signals. Variable resistor VR1 adjusts the current through the MIC and thus determines the sensitivity of MIC. The condenser MIC should be directly soldered on the PCB to get maximum sensitivity. Sleeving the MIC inside plastic tubing can increase its sensitivity error.
A capacitor is an electrical/electronic device that can store energy in the electric field between a pair of conductors (called "plates"). The process of storing
energy in the capacitor is known as "charging", and involves electric charges of equal magnitude, but opposite polarity, building up on each plate. Capacitors are often used in electric and electronic circuits as energy-storage devices. They can also be used to differentiate between high-frequency and low-frequency signals. This property makes them useful in electronic filters. Practical capacitors have series resistance, internal leakage of charge, series inductance and other non-ideal properties not found in a theoretical, ideal, capacitor.
4.6 TRIMMER CAPACITOR
A small button type variable capacitor with a value of 40 pF can be used to adjust the resonant frequency of the tank circuit. The variable capacitor and the inductor coil form the Tank circuit (LC circuit) that resonates in the 88-108 MHz. In the tank circuit, the capacitor stores electrical energy between its plates while the inductor stores magnetic energy induced by the windings of the coil. The resonant frequency can be calculated using the formula:
f = 1 / 2 π √LC = Hz
Where f is the frequency in hertz, x is the coil length, C is the capacitance of trimmer in Farads, and L is the inductance of coil in Henry.
4.7 TANK CIRCUIT
Every FM transmitter needs an oscillator to generate the radio Frequency (RF) carrier waves. The name ‘Tank’ circuit comes from the ability of the LC circuit to store energy for oscillations. The purely reactive elements, the C and the L simply store energy to be returned to the system. In the tank (LC) circuit, the 2N3904 transistor and the feedback 4.7 pF capacitor are the oscillating components. The feedback signal makes the base-emitter current of the transistor vary at the resonant frequency. This causes the emitter-collector current to vary at the same frequency. This signal fed to the aerial and radiated as radio waves.
A plastic wire or Telescopic aerial can be used as antenna. The length of the antenna is very important to transmit the signals in the suitable range. As a rule, the length of the antenna should be ¼ of the FM wave length. To determine the length of antenna, use the following equation. By multiplying the Wave frequency and wave length will give the speed of light.
Speed of Light = Frequency of Oscillation x Wavelength = in kms/ sec
Wave length = Speed of light / Frequency = in meters
Antenna length = 0.25 x wavelength = in meters
Antenna length = 0.25 x wavelength = in meters
By using this formula it is easy to select the antennal length. For the circuit mentioned above, a 25-27inches long antenna is sufficient.
5. FM (FREQUENCY MODULATION)
In telecommunications and signal processing, frequency modulation (FM) conveys information over a carrier wave by varying its instantaneous frequency. This is in contrast with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant.
In analog applications, the difference between the instantaneous and the base frequency of the carrier is directly proportional to the instantaneous value of the input signal amplitude. Digital data can be sent by shifting the carrier's frequency among a set of discrete values, a technique known as frequency-shift keying.Frequency modulation can be regarded as phase modulation where the carrier phase modulation is the time integral of the FM modulating signal.
FM is widely used for broadcasting of music and speech, and in two-way radio systems, in magnetic tape recording systems, and certain video transmission systems. In radio systems, frequency modulation with sufficient bandwidth provides an advantage in cancelling naturally-occurring noise.
Frequency-shift keying (digital FM) is widely used in data and fax modems.
Suppose the baseband data signal (the message) to be transmitted is xm(t) and the sinusoidal carrier is , where fc is the carrier's base frequency and Ac is the carrier's amplitude. The modulator combines the carrier with the baseband data signal to get the transmitted signal:
In this equation, is the instantaneous frequency of the oscillator and is the frequency deviation, which represents the maximum shift away from fc in one direction, assuming xm(t) is limited to the range ±1.
Although it may seem that this limits the frequencies in use to fc ± fΔ, this neglects the distinction between instantaneous frequency and spectral frequency. The frequency spectrum of an actual FM signal has components extending out to infinite frequency, although they become negligibly small beyond a point.
5.1.1 SINUSOIDAL BASEBAND SIGNAL
While it is an over-simplification, a baseband modulated signal may be approximated by a sinusoidal Continuous Wave signal with a frequency fm. The integral of such a signal is,
Thus, in this specific case, equation (1) above simplifies to:
where the amplitude of the modulating sinusoid, is represented by the peak deviation (see frequency deviation.
The harmonic distribution of a sine wave carrier modulated by such a sinusoidal signal can be represented with Bessel functions - this provides a basis for a mathematical understanding of frequency modulation in the frequency domain.
5.2 MODULATION INDEX
As with other modulation indices, this quantity indicates by how much the modulated variable varies around its un-modulated level. It relates to the variations in the frequency of the carrier signal:
where is the highest frequency component present in the modulating signal xm(t), and is the Peak frequency-deviation, i.e. the maximum deviation of the
instantaneous frequency from the carrier frequency. If , the modulation is called narrowband FM, and its bandwidth is approximately .
If , the modulation is called wideband FM and its bandwidth is approximately . While wideband FM uses more bandwidth, it can improve signal-to-noise ratio significantly. For example, doubling the value of while keeping fm constant, results in an eight-fold improvement in the signal to noise ratio. Compare with Chirp spread spectrum, which uses extremely wide frequency deviations to achieve processing gains comparable to more traditional, better-known spread spectrum modes.
With a tone-modulated FM wave, if the modulation frequency is held constant and the modulation index is increased, the (non-negligible) bandwidth of the FM signal increases, but the spacing between spectra stays the same; some spectral components decrease in strength as others increase. If the frequency deviation is held constant and the modulation frequency increased, the spacing between spectra increases.
Frequency modulation can be classified as narrow band if the change in the carrier frequency is about the same as the signal frequency, or as wide-band if the change in the carrier frequency is much higher (modulation index >1) than the signal frequency. For example, narrowband FM is used for two way radio systems such as Family Radio Service where the carrier is allowed to deviate only 2.5 kHz above and below the center frequency, carrying speech signals of no more than 3.5 kHz bandwidth. Wide-band FM is used for FM broadcasting where music and speech is transmitted with up to 75 kHz deviation from the center frequency, carrying audio with up to 20 kHz bandwidth.
5.3 CARSON'S RULE
A rule of thumb, Carson's rule states that nearly all (~98%) of the power of a frequency-modulated signal lies within a bandwidth of
where , as defined above, is the peak deviation of the instantaneous frequency from the center carrier frequency .
The noise power decreases as the signal power increases; therefore the SNR goes up significantly.
FM signals can be generated using either direct or indirect frequency modulation.
· Direct FM modulation can be achieved by directly feeding the message into the input of a VCO.
· For indirect FM modulation, the message signal is integrated to generate a phase modulated signal. This is used to modulate a crystal controlled oscillator, and the result is passed through a frequency multiplier to give an FM signal.
Many FM detector circuits exist. One common method for recovering the information signal is through a Foster-Seeley discriminator. A phase-locked loop can be used as an FM demodulator. Slope detection demodulates an FM signal by using a tuned circuit, which has its resonant frequency slightly offset from the carrier frequency. As the frequency rises and falls, the tuned circuit provides a changing amplitude of response, converting FM to AM. AM receivers may detect some FM transmissions by this means, though it does not provide an efficient method of detection for FM broadcasts.
FM is also used at audio frequencies to synthesize sound. This technique, known as FM synthesis, was popularized by early digital synthesizers and became a standard feature for several generations of personal computer sound cards.
Edwin Howard Armstrong (1890–1954) was an American electrical engineer who invented wideband frequency modulation (FM) radio. He patented the regenerative circuit in 1914, the super-heterodyne receiver in 1918 and the super-regenerative circuit in 1922. He presented his paper: "A Method of Reducing Disturbances in Radio Signaling by a System of Frequency Modulation", which first described FM radio, before the New York section of the Institute of Radio Engineers on November 6, 1935. The paper was published in 1936.
As the name implies, wideband FM (WFM) requires a wider signal bandwidth than amplitude modulation by an equivalent modulating signal, but this also makes the signal more robust against noise and interference. Frequency modulation is also more robust against simple signal amplitude fading phenomena. As a result, FM was chosen as the modulation standard for high frequency, high fidelity radio transmission: hence the term "FM radio" (although for many years the BBC called it "VHF radio", because commercial FM broadcasting uses a well-known part of the VHF band—the FM broadcast band).FM receivers employ a special detector for FM signals and exhibit a phenomenon called capture effect, where the tuner is able to clearly receive the stronger of two stations being broadcast on the same frequency. Problematically however, frequency drift or lack of selectivity may cause one station or signal to be suddenly overtaken by another on an adjacent channel. Frequency drift typically constituted a problem on very old or inexpensive receivers, while inadequate selectivity may plague any tuner.
An FM signal can also be used to carry a stereo signal: see FM stereo. However, this is done by using multiplexing and de-multiplexing before and after the FM process. The rest of this article ignores the stereo multiplexing and de-multiplexing process used in "stereo FM", and concentrates on the FM modulation and demodulation process, which is identical in stereo and mono processes.
A high-efficiency radio-frequency switching amplifier can be used to transmit FM signals (and other constant-amplitude signals). For a given signal strength (measured at the receiver antenna), switching amplifiers use less battery power and typically cost less than a linear amplifier. This gives FM another advantage over other modulation schemes that require linear amplifiers, such as AM and QAM.
Frequency-shift keying is the frequency modulation using only a discrete number of frequencies. Morse code transmission has been implemented this way, as were most early telephone-line modems Radio teletype also use FSK.
FM modulation is also used in telemetry applications, radar, seismic prospecting and newborn EEG seizures modeling.
5.9 SUPER HETERODYNE RECIEVER
In electronics, a super heterodyne receiver (sometimes shortened to superhets) uses frequency mixing or heterodyning to convert a received signal to a fixed intermediate frequency, which can be more conveniently processed than the original radio carrier frequency. Virtually all modern radio and television receivers use the super heterodyne principle.
The diagram at right shows the minimum requirements for a single-conversion super heterodyne receiver design. The following essential elements are common to all superhet circuits:[ a receiving antenna, a tuned stage which may optionally contain amplification (RF amplifier), a variable frequency local oscillator, a frequency mixer, a band pass filter and intermediate frequency (IF) amplifier, and a demodulator plus
additional circuitry to amplify or process the original audio signal (or other transmitted information).
Figure : Block Diagram of Super heterodyne Receiver
5.10 CIRCUIT DESCRIPTION
To receive a radio signal, a suitable antenna is required. This is often built into a receiver, especially in the case of AM broadcast band radios. The output of the antenna may be very small, often only a few microvolts. The signal from the antenna is tuned and may be amplified in a so-called radio frequency (RF) amplifier, although this stage is often omitted. One or more tuned circuits at this stage block frequencies which are far removed from the intended reception frequency. In order to tune the receiver to a particular station, the frequency of the local oscillator is controlled by the tuning knob (for instance). Tuning of the local oscillator and the RF stage may use a variable capacitor, or varicap diode. The tuning of one (or more) tuned circuits in the RF stage must track the tuning of the local oscillator.
5.11 MIXER STAGE
The signal is then fed into a circuit where it is mixed with a sine wave from a variable frequency oscillator known as the local oscillator (LO). The mixer uses a non-linear component to produce both sum and difference beat frequencies signals, each one containing the modulation contained in the desired signal. The output of the mixer may include the original RF signal at fd, the local
oscillator signal at fLO, and the two new frequencies fd+fLO and fd-fLO. The mixer may inadvertently produce additional frequencies such as 3rd- and higher-order intermediation products. The undesired signals are removed by the IF bandpass filter, leaving only the desired offset IF signal at fIF which contains the original modulation (transmitted information) as the received radio signal had at fd.
Historically, broadcast AM receivers using vacuum tubes would save costs by employing a single tube as a mixer and also as the local oscillator. The pentagrid converter tube would oscillate and also provide signal amplification as well as frequency shifting.
5.12 INTERMEDIATE FREQUENCY STAGE
The stages of an intermediate frequency amplifier are tuned to a particular frequency not dependent on the receiving frequency; this greatly simplifies optimization of the circuit. The IF amplifier (or IF strip) can be made highly selective around its center frequency fIF, whereas achieving such a selectivity at a much higher RF frequency would be much more difficult. By tuning the frequency of the local oscillator fLO, the resulting difference frequency fLO - fd (or fd-fLO when using so-called low-side injection) will be matched to the IF amplifier's frequencyfIF for the desired reception frequency fd. One section of the tuning capacitor will thus adjust the local oscillator's frequency fLO to fd + fIF (or. less often, to fd - fIF) while the RF stage is tuned to fd. Engineering the multi-section tuning capacitor and coils to fulfill this condition across the tuning range is known as tracking.Other signals produced by the mixer (such as due to stations at nearby frequencies) can be very well filtered out in the IF stage, giving the superheterodyne receiver its superior performance. However, if fLO is set to fd + fIF , then an incoming radio signal at fLO + fIF will also produce a heterodyne at fIF; this is called the image frequency and must be rejected by the tuned circuits in the RF stage. The image frequency is 2fIF higher (or lower) than fd, so employing a higher IF frequency fIF increases the receiver's image rejection without requiring additional selectivity in the RF stage.
Usually the intermediate frequency is lower than the reception frequency fd, but in some modern receivers (e.g. scanners and spectrum analyzers) it is more convenient to first convert an entire band to a much higher intermediate frequency; this eliminates the problem of image rejection. Then a tunable local oscillator and mixer converts that signal to a second much lower intermediate frequency where the selectivity of the receiver is accomplished. In order to avoid interference to receivers, licensing authorities will avoid assigning common
IF frequencies to transmitting stations. Standard intermediate frequencies used are 455 KHz for medium-wave AM radio, 10.7 MHz for broadcast FM receivers, 38.9 MHz (Europe) or 45 MHz (US) for television, and 70 MHz for satellite and terrestrial microwave equipment.
5.13 BANDPASS FILTER
The received The IF stage includes a filter and/or multiple tuned circuits in order to achieve the desired selectivity. This filtering must therefore have a band pass equal to or less than the frequency spacing between adjacent broadcast channels. Ideally a filter would have a high attenuation to adjacent channels, but maintain a flat response across the desired signal spectrum in order to retain the quality of signal. This may be obtained using one or more dual tuned IF transformers or a multipole ceramic crystal filter.
The received signal is now processed by the demodulator stage where the audio signal (or other baseband signal) is recovered and then further amplified. AM
demodulation requires the simple rectification of the RF signal (so-called envelope detection), and a simple RC low pass filter to remove remnants of the intermediate frequency. FM signals may be detected using a discriminator, ratio detector, or phase-locked loop. Continuous wave (morse code) and single sideband signals require a product detector using a so-called beat frequency oscillator, and there are other
techniques used for different types of modulation. The resulting audio signal (for instance) is then amplified and drives a loudspeaker. When so-called high-side injection has been used, where the local oscillator is at a higher frequency than the received signal (as is common), then the frequency spectrum of the original signal will be reversed. This must be taken into account by the demodulator (and in the IF filtering) in the case of certain types of modulation such as single sideband.
6. CIRCUIT DIAGRAM OF WIRELESS FM MICROPHONE
7. CIRCUIT DESCRIPTION
The above figure shows the circuit diagram of wireless FM microphone .It has two transistor stages. The first one is the common emitter amplifier .The second stage is the voltage controlled oscillator. Capacitor and self-made inductor will vibrate at frequencies in the FM radio band (88 to 108 MHz) and it constitutes the L-C circuit. It is also called tank circuit. It consists of one inductor and two capacitors. This is called Colpitt's oscillator. The physics lying behind this is that the capacitor stores charges between its plates, while the inductor coil stores energy in the magnetic field induced by the coil winding. The tank circuit vibrates at resonant frequency. The resonant frequency is given by
f = 1 / 2 π √LC Hz
Where f is the frequency in hertz, C is the capacitance of trimmer in Farads, and L is the inductance of coil in Henry. The performance of an FM transmitter depends on two important aspects
· Tuning of the FM transmitter to the desired frequency. Even a slight change in the coil specification or slight change in the variable capacitor value can shift the harmonic frequency of the 88 to 108 MHz FM band.
· Length of the Antenna used to transmit the frequency.
The important parameters for the optimum performance of an FM transmitter are :
· Transmitter frequency, output power and range of transmission.
· Antenna length.
· Coil diameter, length, number of turns and gauge of the wire used for coil winding.
The electric microphone has a resistance that depends on how loudly you speak into it. This microphone is battery powered and according to the V=IR Ohm’s Law,
changes in resistance for fixed voltage will result in proportional changes in current. This wireless FM microphone is easy to construct and its transmissions can be picked up on any standard FM radio. It has a range of up to 1/4-mile (400 meters) or more, depending on the line of sight, obstructions by large buildings, etc. If you decide to substitute transistors with something similar you already have, it may be necessary to adjust the collector voltage of Q1 by changing the value of R2 or R3 (because you change transistors, it changes this bias on the base of Q1). It should be about half the supply voltage (about 4 or 5). To find the signal on receiver, make sure there is a signal coming in to the microphone, otherwise the circuit won't work.
To use the microphone, set up a radio in the area at least 10 feet (3 meters) from the project. Find a blank spot on the FM dial and tune the radio up so you can hear the static. Connect a 9-volt battery to the transmitter and listed to the radio. Slowly adjust the trimmer capacitor until "quiet" the receiver; this is the tuned spot. When move hand from the transmitter, then detune the circuit somewhat. It is usually best to leave it detuned and tune the radio in to get the best reception. If you get the tuning range you desire, you can squeeze the coils in the tank circuit closer together to raise the frequency, or pull them apart just a little to lower it.
8. PCB DESIGN
8. 1 PCB DESIGN PROCEDURE
PCB preparation can be done using the following steps.
· Prepare the PCB layout of the circuit in a graph sheet.
· Cut the copper clad sheet in proper dimension and wash it.
· PCB layout is coated with paint or sticker.
· Prepare the ferric chloride solution
· Dip the PCB in to Ferric chloride solution for etching non printed surface.
· Wash cleanly with detergent.
· Drill the holes in necessary any position.
9. PCB LAYOUT
Soldering is the process of joining two or more similar or dissimilar maters by melting another meters having lower melting points. Soldering is an alloy of tin and lead, used for fusing the metals at relatively low temperature about 260uk to 315uk.The joint where the two metal conductors are to be fused is heated and solder is applied so that it can melt and cover the connection. The reason for soldering connections is that it makes a good bond between the joining metals , covering the joints completely to prevent oxidization. The coating of solder provides protection for practically long period of time. The trick in soldering is to heat the joint, not the solder. When the soldering is hot enough to melt the solder, it follows smoothly to fill all cracks forming a shiny cover without any space. Do not move the joint until the solder has set. Either the soldering iron or soldering gun can be used rated at 25W to 100W.In addition to this solder flux is used to remove any oxide films on the metal being joint. Otherwise they cannot be joined together.
9.1 SOLDERING FLUXES
In order to make the surface accept the solder readily, the component terminals should be for from order and other abstractly films. Soldering flux cleans the orders from the surface of the metal. Zinc chloride, aluminums chloride, and rosin at the commonly used fluxes.
Solder is used for joining two or more mental at temperature below their melting point. The popularly used solders on alloy are alloys of tin (60%) and lead (40%) that metals at stiff and solidifies when it cools.
9.3 SOLDERING IRON
It is used the melt the solder and apply at the joints in the circuit.
Ø Working with a simple dry cell power supply.
Ø It is user friendly.
Ø Low cost.
Ø Easy to install.
Ø Simple circuit.
Ø Greater freedom of movement for the artist or speaker.
Ø Avoidance of cabling problems common with wired microphones, caused by constant moving and stressing the cables.
Ø Sometimes limited range (a wired balanced XLR microphone can run up to 300 ft or 100 meters). Some wireless systems have a shorter range, while more expensive models can exceed that distance.
Ø Possible interference with or, more often, from other radio equipment or other radio microphones, though models with many frequency-synthesized switch-selectable channels are now plentiful and cost effective.
Ø Operation time is limited relative to battery life; it is shorter than a normal condenser microphone due to greater drain on batteries from transmitting circuitry, and from circuitry giving extra features, if present.
Ø Noise or dead spots (places where it doesn't work, especially in non-diversity systems).
Ø Limited number of operating microphones at the same time and place, due to the limited number of radio channels (frequencies).
Ø It is used in seminar halls, class rooms, for a school or college radio etc.
The mini project 'wireless FM microphone' is developed from the elementary idea of making a wireless hand piece, which can be used in a seminar hall, auditorium etc. This idea forced us to proceed with our project. As our project deals with transmitter & the most common receiver is FM receiver, we decided to make the FM Transmitter.
15. FUTURE SCOPE
As the field of Information Technology and Communication is developing day-by-day, the necessity of more sophisticated equipments and discoveries is raising up. Hence, more enhanced version of our project, wireless FM microphone can be implemented in various circuits.
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Fun Learning with Printable Flash Cards
Here you will find our selection of free printable flash cards for preschool learning (and beyond!). Flash cards are a great way for kids to learn the basic elements and memorize them through short repeat sessions. You’ll find helping them learn their first abc, animal names and numbers incredibly rewarding.
A few minutes here, a few minutes there, whether at home, traveling, in the park or at Auntie’s it’s learning on the go. These lovely cards turn learning into playing (… but we also love decorating kids’ rooms by sticking them on the wall or putting them in picture frames.)
We’ve made all our printable flash cards here free for everybody and of course you can print them as many times as you like!
Alphabet Flash Cards
Helping the little one’s first learning fun and sweet!
Vocabulary Flash Cards
Learning new words and concepts is great fun!
Number & Math Flash Cards
Various flash cards for all your math activities.
Shapes & Colors Flash Cards
Try combining abstract shapes and pretty colors with various colorful activities.
We have a growing selection of children’s resources for preschool, homeschool & classroom learning activities. Please check back soon to see what’s new. Thank you!
We’d also love to hear from parents and teachers with suggestions.
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Prepare this delightful combination of potatoes and vegetables on the grill or in the oven. It can be made ahead of time and served at room temperature or reheated.
By Patty James
Why is it important to eat lots of different colored fruits and vegetables? Because each colored vegetable and fruit has unique properties and there is strong evidence of interactions between the colors that are beneficial to your health. Eating by the Rainbow is vitally important to your well-being.
Here are the colors:
Red foods contain lycopene that helps rid the body of damaging free radicals and protects against prostate cancer, as well as heart and lung disease. The red foods are loaded with antioxidants thought to protect against heart disease by preventing blood clots, and may also delay the aging of cells in the body.
Orange and Yellow foods contain alpha carotene, which protects against cancer, but also contain beta-carotene, which the body converts to vitamin A, protecting the skin against free-radical damage. Beta-carotene is also good for night vision.
Yams and sweet potatoes
Oranges and Tangerines
Yellow summer or winter squash
Green foods contain the chemicals that help ward off cancer by inhibiting carcinogens. Chlorophyll is the component that makes plants green, and it is purifying in the body. Many green foods also contain calcium and minerals.
Kale, spinach, and other leafy greens
Blue, Indigo, and Violet foods contain the compound anthocyanins that not only give food their color but also have been shown to reduce the risk of high blood pressure and increasing heart health.
Plums, fresh and dried
White foods, though not part of the color of the rainbow, contain properties that have anti-tumor qualities, such as allicin in onions as well as other health-improving antioxidants such as the flavanoids. The white foods, like bananas and potatoes, contain potassium as well.
So how do you incorporate these fruits and vegetables into your daily eating habits?
Here are some sample menus to get you started:
An orange. Sauté 1/2 red pepper, ½ onion, 2 shitake mushrooms, and 2 cloves garlic. Add 3 cups leafy greens (spinach leaves are fine) and 3 eggs. Cook until eggs are done and serve.
Strawberries. Oatmeal made with cubed butternut squash or pureed pumpkin, topped with raw walnut pieces and raw pumpkin seeds.
Turkey sandwich on whole grain bread with sprouts, lettuce, tomato slices, avocado, and grated carrots. Serve with a 2-cup salad made with romaine lettuce and raw cauliflower, broccoli, and garbanzo beans.
Spinach salad topped with black olives, cherry tomatoes, cucumbers, green onions, and cauliflower. Add beans or chicken if you like. Toss with fresh lemon juice and either olive oil or flax oil or a combination of the two. Sprinkle fresh parsley, chopped, on top.
Grilled fish or chicken breast or black beans and brown rice (protein). Coleslaw made with green and red cabbage with red onions and grated carrots. Baked yam.
Pasta primavera made with spinach fettuccini, sautéed red peppers, onions, garlic, zucchini, carrots, and whatever else is in season.
1 cup blueberries and cantaloupe
Jicama slices with salsa and celery with hummus or peanut or almond butter
Pineapple chunks and banana slices
Raw veggies with your favorite dip. Hummus is a good choice.
Tangerine slices with herb tea
Remember that you need 5–9 cups of vegetables and fruits a day for good health. Make sure at least half of your veggies are raw. Don't forget that juicing can incorporate many colored fruits and veggies easily and may be a good choice for those who may not be able to chew raw fruits and veggies.
Patty James is a Certified Natural Chef with a Master's degree in Holistic Nutrition and was founder and director of the Patty James Cooking School and Nutrition Center, the first certified organic cooking school and nutrition center in the country. She created the Patty James Health Guide, a guide to life-long healthy eating and lifestyle. Patty is a frequent guest speaker in public and private schools around the US, the Clinton Foundation in New York, as well as to health practitioners and organizations. Patty runs Shine the Light on America's Kids, an organization whose mission is to shine the light on all aspects of kids' health in America. She is the author of More Vegetables, Please! Website: PattyJames.com and ShineTheLightOnKids.org
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Biologists have known for decades that cells use tiny molecular motors to move chromosomes, mitochondria, and many other organelles within the cell, but no one has been able to understand what "steers" these engines to their destinations. Now, researchers at the University of Rochester have shed new light on how cells accomplish this feat, and the results may eventually lead to new approaches to fighting pathogens and neurological diseases.
Michael Welte, associate professor of biology, shows in a paper published in today's issue of Cell that the mechanisms that control the molecular motors are quite different from what biologists have previously believed. Before these findings, scientists assumed that the number of motors attached to an organelle determined how far and fast the organelle could travel, but Welte and colleagues have discovered that it is not the number of motors, but yet-to-be-discovered molecules that are likely the master regulators.
"The fact that motor number has nothing to do with regulating transport is extremely surprising, and somewhat unsettling to people working in vitro," says Welte. "It says we're really missing something when we study these motors only in the test tube instead of in a living cell."
Intracellular transport is crucial to a cell's health, says Welte. For instance, during cell division, one copy of each of the cell's chromosomes migrates to one side of the cell while the other copy moves to the other side. If this movement is disturbed, it could cause an imbalance of chromosomes in the daughter cells, which might die or become cancerous. Similarly, neurons, some of which are as much as three feet in length, manufacture proteins and organelles at one end and then must move that precious cargo all the way to the far end where they'll be used. This is an enormous task, says Welte, and defects in this transport are thought to cause a number of neurological diseases.
Given the difficulty of investigating these tiny motors acting within the cell, biologists have performed basic experiments on them outside of the cell in a carefully controlled environment. This led them to believe that the speed and distance an organelle could be transported depended on how many motors were pulling it, says Welte. Thus, the scientists reasoned, perhaps the cell simply attaches the right number of motors to an organelle to send it the right distance. Although this "multi-motor" hypothesis is very simple and elegant, says Welte, whether it actually holds true within living cells had never been tested.
Welte's graduate student, Susan Tran, decided to perform that test. She created fruit-fly eggs lacking a type of molecular motor called kinesin and found that certain organelles stopped moving—strong evidence that kinesin is responsible for their transport. Tran then made another type of mutant eggs, this time ones that produced only about half the number of kinesin motors of a regular egg. In both types of eggs, organelles were transported with the same speed and the same distance.
Welte needed to know if this equality was because the normal egg was simply utilizing only half the available kinesin motors, or if some master regulator was controlling the organelle's progress, regardless of the number of motors moving it. To do this, Welte turned to Steven Gross, associate professor of developmental and cell biology at the University of California. Gross' group uses an apparatus called "optical tweezers" that employs laser light to measure the tiny forces the motors generate. The team found that organelles in regular cells are pulled with twice the force of Tran's mutant, low-kinesin cells.
"That clinched it for us," says Welte. "Yes, there are multiple motors moving organelles around, but exactly how many doesn't matter. There is something else in the cell that's controlling all the motors. That opens up a big area for research—find what's driving these motors and maybe we can control them all by controlling one thing."
Welte and his team are now looking at where in the cell this signal comes from and how it influence the motors. Although Welte's team studied fruit fly eggs, the motors moving the organelles are present in all animals and employed for many tasks, including transport in human neurons.
Welte also points out that viruses, including HIV, make use of the same kind of motors to move about the cell, first to get from the site of penetration to the nucleus, where they multiply, and then to get progeny viruses back to the cell surface. If Welte and others can figure out how cells normally control these motors, it may be possible to prevent HIV from taking control of the motors and thus to keep it, and other intracellular pathogens, at the edge of the cell where they can do little harm.
This research was funded by the National Institutes of Health, and includes researchers from the University of Rochester, the University of California Irvine, and University of Texas at Austin.
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The latest news from academia, regulators
research labs and other things of interest
Posted: December 7, 2009
Super cool atom thermometer
(Nanowerk News) As physicists strive to cool atoms down to ever more frigid temperatures, they face the daunting task of developing new, reliable ways of measuring these extreme lows. Now a team of physicists has devised a thermometer that can potentially measure temperatures as low as tens of trillionths of a degree above absolute zero. Their experiment is reported in the current issue of Physical Review Letters and highlighted with a Viewpoint in the December 7 issue of Physics.
Physicists have developed a new thermometry method suitable for measuring temperatures of ultracold atoms. (Illustration: Alan Stonebraker)
Physicists can currently cool atoms to a few billionths of a degree, but even this is too hot for certain applications. For example, Richard Feynman dreamed of using ultracold atoms to simulate the complex quantum mechanical behavior of electrons in certain materials. This would require the atoms to be lowered to temperatures at least a hundred times colder than what has ever been achieved. Unfortunately, thermometers that can measure temperatures of a few billionths of a degree rely on physics that doesn't apply at these extremely low temperatures.
Now a team at the MIT-Harvard Center for Ultra-Cold Atoms has developed a thermometer that can work in this unprecedentedly cold regime. The trick is to place the system in a magnetic field, and then measure the atoms' average magnetization. By determining a handful of easily-measured properties, the physicists extracted the temperature of the system from the magnetization. While they demonstrated the method on atoms cooled to one billionth of a degree, they also showed that it should work for atoms hundreds of times cooler, meaning the thermometer will be an invaluable tool for physicists pushing the cold frontier.
Source: American Physical Society
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Water in the ear
Living in Thailand is great for those of us who enjoy swimming and water sportsBut the hot and tropical climate doesn't mean that you are safe from "swimmer's ear syndrome" or otitis.
Swimmer's ear or otitis externa is an inflammation, irritation or infection of the skin of the outer ear canal. After swimming or showering, water remaining in the ear leaves the ear canal moist, making it a good environment for bacterial growth. Rubbing the ear with a finger or using cotton tips to clean the ears lead to abrasions of the ear canal skin. Bacteria then invade the skin and cause infection of the ear canal or swimmer's ear. Swimming in polluted water and excessive cleaning worsen the infection.
Symptoms of swimmer's ear start with itching and mild discomfort, then progress to pain, swelling and redness in the ear, feeling of fullness or a blocked ear, fluid (pus) drainage from the ear, lymph node swelling and fever. The diagnosis is made by history, symptoms and ear examination. Pain, redness or swelling of the outer ear canal leads to the diagnosis of otitis externa (swimmer's ear). However, in recurrent infections, the doctor may collect discharge from the ear canal for culture to identify the causative bacteria. Treatment for swimmer ears includes cleaning of the ear canal, application of eardrops that inhibit bacterial or fungal growth and reduce swelling, and/or oral antibiotics. Pain relief medication may be given to minimise the discomfort.
As with all infections, prevention is better than cure. Below are some tips that should keep you safe from otitis externa.
1. Keep your ear dry because a dry ear is unlikely to become infected. Tip your head to the side to drain water out of your ear after swimming and showering. Swim mould can also be used to prevent water to the ear.
2. Do not swim in polluted water.
3. Do not put anything into your ear including finger, cotton, cloth or paper.
4. If you have an ear infection, do not go swimming.
Dr Savitree Chaloryoo, is a specialist paediatric audiologist at the Hearing Center, on the third floor of Samitivej Srinakarin Hospital. She can be contacted at (02) 378 9000.
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The pulling power of chaos
Our Science Essay ponders the riddle of the wandering stars. Starting with Poincaré, complex maths i
What is the most efficient way to get a space probe to its target? When Apollo 11 went to the moon in 1969 it followed a conventional Hohmann transfer orbit. Imagine an egg-shaped outline, with the earth at the bottom. As the spacecraft comes up the left-hand side, it burns fuel to accelerate, and swings into orbit around the moon.
This was the quickest route – aside from the impractical one of flying straight out by burning fuel the whole time – and, in a manned mission, speed was of the essence. However, we now know that when efficient use of fuel is the main objective, and time is unimportant, less direct routes can be much better. When Nasa sent the Cassini probe to Saturn, it first went inwards in the solar system, undergoing two close encounters with Venus. Then it swung back past the earth and on to Jupiter before making a sharp turn to meet Saturn.
Trajectories such as this exploit the slingshot effect, in which the spacecraft steals energy from a planet. The tiny spacecraft speeds up considerably, pulled towards the planet by gravity; the massive planet slows down very slightly, but not enough to notice. Yet there is another, subtler effect of orbital dynamics which is also being used to get spacecraft to their targets using as little fuel as possible: chaos.
The technique was first used in 1991. A Japanese space probe, Hiten, had been surveying the moon. Having completed its mission and returned to orbit the earth, it had pretty much run out of fuel. Edward Belbruno, an orbital analyst at Nasa’s Jet Propulsion Laboratory in Los Angeles, came up with an idea that sounded impossible. He wanted to extend its useful life and enhance its scientific value by sending it back to the moon. Then it would visit the moon’s Trojan points – the points in space 60 degrees ahead of and behind the moon in its orbit where gravity and centrifugal forces cancel each other out. There it could search for cosmic dust that might have become trapped.
It sounded crazy, but Belbruno knew a way to do it. Mathematicians and physicists had realised that the motion of bodies under gravity can be chaotic – highly irregular, despite obeying entirely deterministic laws. Chaotic orbits are sensitive to very small disturbances. Normally, this feature is seen as an obstacle to prediction, but Belbruno realised that it could be used to advantage. Very small changes in position or speed, which use very little fuel,
can cause large changes to the trajectory. That makes it easy to redirect the spacecraft in a fuel-efficient, though possibly slow, manner.
One place where chaotic orbits can arise is somewhere called the “L1 Lagrange point” between the earth and the moon, where the net gravitational force is zero (essentially, objects are “suspended” between the two bodies because of the forces generated by each). Belbruno designed a new orbit that took Hiten close to the L1 point, where a short, carefully calculated burst of its rockets would loop it out to where he wanted it to go. He faxed his proposals, unsolicited, to the Japanese team; they loved the idea. When the probe arrived at L1, it found there was no more dust than you’d expect; after a few years orbiting the moon, Hiten was crashed into its surface in 1993. Still, it had ushered in a new era of space travel. A similar trick was used for Nasa’s Genesis mission to bring back samples of the solar wind.
The first Oscar
Our fascination with the planets goes back to prehistoric times, when human eyes watched the star-spangled splendour of the night sky and human minds were awed by the cosmic spectacle. Countless stars moved across the sky, pinpricks of light on a gigantic, rotating velvet-black bowl.
A few of those pinpricks of light, however, did not obey the rules. They went walkabout. The Greeks called them planetes – wanderers; we call them planets. Their paths are complicated and sometimes loop back on themselves. It is not surprising that the ancients attributed their movements to the caprices of supernatural beings.
Ptolemy, a Roman who lived in Egypt around AD120, began the lengthy process of taming the solar system, proposing that we live in an earth-centred universe in which everything revolves around humanity in complex combinations of circles supported by giant crystal spheres. Around 1300, the Persian Islamic philosopher Najm al-Katibi proposed a heliocentric (sun-centred) theory, but changed his mind. The big breakthrough came in 1543 when Nicolaus Copernicus published On the Revolutions of the Celestial Spheres. He was clearly influenced by al-Katibi, but he went further, setting out an explicitly heliocentric system. Among its implications was the novel thought that human beings were not at the centre of things. To the Christian Church, this suggestion was contrary to doctrine, and explicit heliocentrism was heresy.
The riddle of the wandering stars was finally answered in 1609 by Johannes Kepler, an assistant to the astronomer Tycho Brahe. When his employer died unexpectedly, Kepler took over as court mathematician to Emperor Rudolph II. His main role was casting imperial horoscopes, but he also had time to analyse the orbit of Mars. For years, he tried without success to fit the planet’s orbit to an egg-shaped curve, sharper at one end than the other. In 1605 he decided to try an ellipse, equally rounded at both ends. He discovered that this shape fitted the observations, and declared: “Ah, what a foolish bird I have been!”
In 1609, Kepler published A New Astronomy, stating two basic laws of planetary motion. First law: all planets move in ellipses with the sun as a focus. Second law: a planet moves along its orbit in such a manner that it sweeps out equal areas in equal times. In 1619 he returned to planetary orbits in The Harmony of the World. The book contained many curious ideas – for example, that planets emit musical sounds as they roll round the sun. But it also contained his third law: the squares of the time taken for planets to orbit are proportional to the cubes of their distances from the sun.
This work led to one of the greatest scientific discoveries of all time. In his Mathematical Principles of Natural Philosophy of 1687, Isaac Newton proved that Kepler’s three laws are equivalent to a single universal law of gravitation. Two bodies attract each other with a force that is proportional to their mass and inversely proportional to the square of the distance between them. Newton’s law of gravity had a huge advantage over Kepler’s ellipses: it applies to any system of bodies, however many there might be. The price to be paid is the way the law prescribes the orbits – not as geometric shapes, but as solutions of a mathematical equation. The problem is to solve it.
Newton achieved that for two bodies – a planet plus the sun – and the answer is what Kepler had already discovered: the bodies move around their common centre of gravity in elliptical orbits. But some questions involve more than two bodies. If you want to predict the motion of the moon with high precision, you have to include both the sun and the earth in your equations. So, fresh from Newton’s success with the motion of two bodies under gravity, mathematicians and physicists moved on to three bodies. Their initial optimism rapidly dissipated; the three-body problem turned out to be very different from the two-body problem. In fact, it defied solution.
Only in the late 19th century did its true complexity become apparent, however, when Henri Poincaré tried to win a scientific prize. The 60th birthday of Oscar II, king of Norway and Sweden, happened in 1889. The Norwegian mathematician Gösta Mittag-Leffler persuaded the king to mark the occasion by announcing a prize for calculating the motion of any number of bodies under gravity and finding out whether the solar system is stable.
Poincaré decided to start with the simplest case: two bodies (say the sun and a planet) moving in perfect circles, with the third body being a dust particle of negligible mass. Even that version proved too ambitious and he failed to solve it, but he made so much progress that he was awarded the prize anyway.
In particular, Poincaré proved that sometimes the orbit of the dust particle became extraordinarily messy. He deduced this from some highly original ideas that made it possible to infer features of the solutions without actually solving the equations, saying: “One is struck by the complexity of this figure that I am not even attempting to draw.” We now recognise Poincaré’s discovery as a sign that the dynamics of such a system are chaotic. The equations are not random, but their solutions can be very irregular, sharing features with properly random processes. This idea is colloquially known as chaos theory, and it all goes back to Poincaré and his Oscar award.
Well, that’s the story that historians of mathematics used to tell. Around 1990, however, June Barrow-Green found a copy of Poincaré’s prize-winning memoir in the depths of the Mittag-Leffler Institute in Sweden. She realised that when he submitted his work he had overlooked the chaotic solutions. He spotted the error before the memoir was published, and paid to have the original version destroyed and a corrected version printed. His initial oversight lay undiscovered for a century.
Building on Poincaré’s discovery, we now know that the three-body problem does not have simple solutions. Even so, vast progress has been made on the many-body problem in special cases; for example, when all of the bodies have the same mass. This is seldom a realistic assumption in celestial mechanics, but it is sensible for some models of elementary particles, such as electrons. In 1993, Cristopher Moore at the Sante Fe Institute found a solution to the three-body problem in which the bodies play follow-my-leader along the same orbit. Even more surprising is the shape of the orbit – a figure of eight.
Stranger than imagination
In 2000, the Spanish mathematician Carles Simó used a computer to show that this configuration is stable: it persists after small disturbances. Indeed, it remains stable even when the three masses are slightly different, so, somewhere in the universe, there might be three stars of almost identical mass, chasing each other along a figure-of-eight path.
The same year, Douglas Heggie of Edinburgh University estimated that the number of such triple stars lies somewhere between one per galaxy and one per universe. The figure-of-eight orbit is a planetary dance in which the bodies return to the same positions but swap their identities, each occupying the location that the body in front of it has vacated. This kind of orbit is called a choreography. Using a computer, Simó has found a huge number of choreographies, which can involve a large number of bodies.
The solar system is, was, and will be, far stranger than we imagine. Consider the comet Oterma. A century ago, Oterma’s orbit was well outside that of Jupiter. After a close encounter with the giant planet, its orbit shifted inside that of Jupiter. After another close encounter,
it switched back to outside again. We can confidently predict that Oterma will continue to switch orbits in this way every few decades, not because it breaks Newton’s law, but because it obeys it. Oterma’s gyrations are a far cry from Kepler’s tidy ellipses. The explanation is straight out of science fiction. In Pandora’s Star, Peter Hamilton portrays a future where people travel to planets encircling distant stars by train, running the railway lines through a wormhole, a short cut through space-time.
In his Lensman series, Edward Elmer “Doc” Smith came up with the hyperspatial tube, which malevolent aliens used to invade human worlds from the fourth dimension. Although we don’t have wormholes or aliens from the fourth dimension, the planets and moons of the solar system are tied together by a network of multidimensional mathematical tubes that provide energy-efficient routes from one world to another. If we could visualise the ever-changing gravitational landscape that controls the planets, we would see these tubes, swirling along with the planets as they orbit the sun.
Oterma’s orbit lies inside two tubes, which meet near Jupiter at a Lagrange point. One tube lies inside Jupiter’s orbit, the other outside.
At the Lagrange point the comet can switch tubes, or not, depending on chaotic effects of Jovian and solar gravity; once inside a tube, however, Oterma is stuck there until the tube returns to the junction. Like a train that has to stay on the rails, but can change its route to another set of rails if someone switches the points, Oterma has some freedom to change its itinerary, but not a lot.
As such, the way to plan an efficient mission profile is to work out which tubes are relevant to your choice of destination. Then you route your spacecraft along the inside of the first inbound tube, and when it gets to the associated Lagrange point you fire a quick burst on the motors to redirect it along the most suitable outbound tube. That tube naturally flows into the corresponding inbound tube of the next switching point . . . and so it goes on.
Plans for future tubular space missions are already being drawn up. In 2000, Wang Sang Koon, Martin Lo, Jerrold Marsden and Shane Ross used the tube technique to plot what they described as a “Petit Grand Tour” – an energy-efficient route – around the moons of Jupiter, ending in orbit around Europa. In 2005, Michael Dellnitz, Oliver Junge, Marcus Post and Bianca Thiere used tubes to plan an energy-efficient mission from the earth to Venus.
Their route would use one-third of the fuel required by the European Space Agency’s Venus Express mission, which has observed Venus since 2006.
Past, present, future The influence of tubes may go further. Dellnitz has discovered evidence of a natural system of tubes connecting Jupiter to each of the inner planets. This remarkable structure, known as the Interplanetary Superhighway, hints that Jupiter, long known to be the dominant planet of the solar system, also plays the role of a celestial Grand Central Station. In the past, its tubes may well have organised the formation of the entire solar system, determining the spacings of the inner planets.
So, is the solar system stable? The answer is a definite “maybe”. Two research groups, run by Jack Wisdom of the Massachusetts Institute of Technology and Jacques Laskar of the Observatoire de Paris, have pioneered highly accurate computational methods to understand the probable future of the solar system. Wisdom’s group has found that Pluto behaves chaotically over timescales of several hundred million years.
In 1999, Norman Murray of the Canadian Institute for Theoretical Astrophysics and Matthew Holman of the Smithsonian Astrophysical Observatory discovered that the orbit of Uranus can also change chaotically, so that it occasionally gets close to Saturn, with the possibility that Uranus would then be ejected from the solar system. However, it will probably take about one quintillion years for this to happen. (The sun will blow up into a red giant much sooner, about five billion years from now. The earth will move outwards and might just escape being engulfed, even though tidal interactions will probably pull it into the sun. In any case, our planet’s oceans will boil away long before that. And, anyway, the typical lifetime of a species is no more than five million years.)
It’s not just the future that is chaotic; the same methods can be used to investigate the solar system’s past. In 1993, Renu Malhotra of the University of Arizona realised that the early solar system must have been far more dynamic than had been assumed. As the planets were condensing from the primal gas cloud surrounding the sun, there came a time when Jupiter, Saturn, Uranus and Neptune were nearly complete. Among them circulated huge numbers of rocky and icy “planetesimals”, small bodies about ten kilometres across. Many of these were ejected into the wider solar system, reducing the energy of the four giant planets. Neptune migrated outwards. So did Uranus and Saturn. Jupiter, the big loser in the energy stakes, moved inwards.
So, our solar system’s apparently stable plan arose through an intricate dance of the giants, in which they threw the smallest bodies at each other in a riot of chaos.
Is the solar system stable? Probably not, but don’t worry: we won’t be around to find out.
Ian Stewart is emeritus professor of mathematics at the University of Warwick. His latest book is “17 Equations That Changed the World” (Profile, £15.99)
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Turner to Monet
A large, ambitious scene of arctic exploration, imagined fifty years after the event and half a world away, seems an unlikely Australian project. Jenner, a self-taught English immigrant painter, tried to establish a cultivated artistic climate in Queensland at the end of the nineteenth century. Such grand history paintings, employing all the stratagems of the Sublime, would make the artist’s reputation unassailable, he thought, as well as serving another purpose, that of elevating public taste.
His subject was Sir John Franklin’s doomed expedition of 1845, to find the fabled Northwest Passage between the Atlantic and Pacific Oceans. The venture fascinated the public, writers, and the press for decades; the British government, prodded by Lady Franklin, sent thirty-two expeditions to find the vanished explorers, Swinburne wrote a long poem in 1860, and Jules Verne published two novels inspired by the topic in the 1870s. Reports of cannibalism among survivors kept the story alive and scandalous.
Jenner remembered arctic scenery and details from a journey taken in his youth. He sailed in the early 1850s, he said, on ‘a voyage to Lapland, Nova Zembla and Spitzbergen’.1At the age of eighteen in 1855, Jenner joined the Royal Navy for a decade, then retired to his birthplace, Brighton, to become an artist. Unhappy with his prospects as a marine and genre painter there, he emigrated with his large family to Brisbane in 1863. En route he witnessed the effects of Krakatoa’s eruption, another instance of Nature’s grand and sublime spectacles.
For his modern history painting Cape Chudleigh, Coast of Labrador, Jenner painted icebergs in Labrador, populated by hundreds of great auks – large, penguin-like birds, hunted to extinction in the 1840s. The whole is lit by a full moon under a cloudy sky. Apart from icy white and blue for freezing water, sea and sky, atmosphere and rocks are rendered in smoky brown and grey, with red reflected from the ship on fire behind an iceberg.2
The ghostly theatre of Franklin’s fatal voyage is accentuated by Jenner’s spectral depiction of translucent ice, a disappearing mountain and bizarre spectating birds, scattered like the ill-fated crew through the sea and absent land. Jenner’s invisible hero, Franklin, was linked closely to colonial Australia’s brief history: he accompanied Matthew Flinders on the Investigator’s initial circumnavigation of the continent in 1801–04, and served as Governor of Tasmania from 1836 to 1843.
Nonetheless, the artist’s extravagant vision of the voyage was profoundly unfashionable. The extremes of the Sublime, especially delight in terror and heightened emotions, had dissipated their effect by the end of the century, while unsuccessful English explorers no longer caught the imagination of poets and engravers. European aesthetic manners and themes were replaced in Australia by the local and immediate paintings of the Heidelberg school.3 Jenner was triply unfortunate, in that his subject and style were no longer appreciated, and any audience was sparse. Nonetheless, he ensured some posterity by reworking and donating this large canvas to the infant Queensland National Art Gallery upon its opening in 1895.
1 Margaret Maynard, ‘Jenner, Isaac Walter (1837–1902)’, Australian Dictionary of Biography, online edition, viewed November 2007, adb.online.anu.edu.au.
2 Gavin Fry, Bronwyn Mahoney, Bettina MacAulay, Isaac Walter Jenner, Sydney: Beagle Press, 1994, p. 34.
3 See Glen R. Cooke, Catalogue worksheet for Acc. number 1:0014, Queensland Art Gallery, ms.
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A new species of dinosaur is the smallest ever found in North America scientists report in the Proceedings of the Royal Society of London B today.
The pigeon-sized Fruitadens haagarorum lived 150 million years ago in the Late Jurassic period. It was an agile fast runner, handy as it lived at the same time as other giant dinosaurs such as the long-necked Brachiosaurus and the meat-eating Allosaurus.
Tiny jaw fossil of the Fruitadens dinosaur showing 5 teeth © The Dinosaur Institute, Los Angeles Museum of Natural History
An international team led by Dr Richard Butler of the Bavarian State Collection for Palaeontology, Germany, and the Natural History Museum, London, made the discovery by re-examining fossils uncovered in the 1970s.
'This discovery demonstrates just how remarkably diverse and successful the dinosaurs were,' says Dr Butler. 'We have this diminutive dinosaur living alongside titans such as Brachiosaurus that probably weighed 40,000 times as much.'
The team studied fossils from 4 Fruitadens individuals that were uncovered from the Morrison Formation in Colorado and kept at the Natural History Museum, Los Angeles County. Tiny details inside the leg bones revealed Fruitadens grew to about 70cm in length and weighed less than 1kg.
Fruitadens had a combination of different shaped teeth including canine-like teeth at the front of the lower jaw and leaf-shaped teeth in the cheek area. This, combined with its small size, means Fruitadens was probably an omnivore, eating both plants and small animals.
Fruitadens belonged to the heterodontosaurids, an important group of early dinosaurs previously unknown from North America, and is one of the latest surviving members of this group.
Heterodontosaurids, also had the unusual combination of canine-like and leaf-shaped teeth. Earlier members of this group were larger than Fruitadens and adapted to have a diet of tough vegetation. The more recent Fruitadens evolved to be smaller and have a more generalised varied diet.
Fossil experts have been studying the Morrison Formation rocks where Fruitadens was uncovered for 130 years.
Dozens of dinosaur species have been discovered there and there could be many more to come.
Dr Butler says of the site, 'It is still possible to discover completely unique and remarkable species. If dinosaur ecosystems were that diverse, who knows what astonishing beasts are waiting for us to discover?'
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The International Guidelines on HIV/AIDS and Human Rights
OHCHR and UNAIDS published the International Guidelines on HIV/AIDS and Human Rights in 1998 as a tool for States in designing, co-ordinating and implementing effective national HIV/AIDS policies and strategies. The Guidelines were drafted by experts at an international consultation in 1996 and provide the framework for a rights-based response to the HIV/AIDS epidemic by outlining how human rights standards apply in the context of HIV/AIDS and translating them into practical measures that should be undertaken at the national level, based on three broad approaches:
- improvement of government capacity for multi-sectoral coordination and accountability;
- reform of laws and legal support services, with a focus on anti- discrimination, protection of public health, and improvement of the status of women, children and marginalised groups; and
- support and increased private sector and community participation to respond ethically and effectively to HIV/AIDS.
OHCHR encourages governments, national human rights institutions, non-governmental organisations and people living with HIV and AIDS to use the Guidelines for training, policy formulation, advocacy, and the development of legislation on HIV/AIDS-related human rights.
In light of developments in adressing the epidemic, a Third International Consultation in 2002 revised Guideline 6 on access to prevention, treatment, care and support.
A consolidated version of the International Guidelines on HIV-AIDS and Human Rights was launched in August 2006 to coincide with the XVIth International AIDS Conference and the tenth anniversary of the Guidelines themselves.
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• Incubation: 18-20 days
• Clutch Size: 4 eggs
• Young Fledge: 16-21 days after hatching
• Typical Foods: insects, aquatic invertebrates and seeds
Female red phalaropes are stunning -- they are a rich chestnut color with a dark crown and white face. However, virtually all Ohio birds are in drab non-breeding plumage.
Habitat and Habits
This species prefers the open waters of Lake Erie. It is most typically found along stone jetties and breakwalls in sheltered harbors. The flight call is similar to that of the red-necked phalarope, but generally higher pitched.
Reproduction and Care of the Young
Breeding takes place in Alaska and northern Canada. Nests are hollows in the ground of marshy tundra. The male raises the young.
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In the early 1990s, researchers, including Itzhaki, found evidence suggesting that as we age, the herpes virus begins moving from its hideout near the bottom of the skull directly into the brain (possibly because our immune systems lose some bite). Indeed, one Journal of Pathology study found the virus in a high proportion of postmortem brain samples taken from people who'd died in their later decades, while it was absent in those from people who'd died in youth or middle age.
What effect does the virus have when it reaches your brain? The short answer: That depends. In certain people it seems to do much less damage than in others; just as some of us never develop cold sores, some of us can have the herpes virus inside our brains without any horribly ill effects. But Itzhaki believes that in other people—specifically those who carry APOE e4, a gene form, or allele, strongly linked to Alzheimer's—the virus is not only reactivated by triggers like stress or a weakened immune system, but also actually begins to create the proteins that form the plaques and tangles presumed to be responsible for Alzheimer's.
If you're looking for evidence, Itzhaki can show you a stack of it. In two studies, for example, she and several colleagues took brain samples from 109 deceased people—61 of whom had had Alzheimer's, 48 of whom hadn't—to search for any correlation between herpes, APOE e4, and Alzheimer's.
Their results: People who had both the APOE e4 gene and the herpes virus in their brains were 15 times more likely to have Alzheimer's than people who had neither. (The researchers also found, intriguingly, that people who suffered from recurrent cold sores were almost six times as likely to have the APOE e4 gene as those who didn't get cold sores.)
A decade later, Dr. Federoff, then working at the University of Rochester, administered the herpes virus to four different groups of mice, each of which had a different variation or absence of the APOE gene. He found that in mice with the specific APOE e4 variation, the virus was slower to become dormant than it was in mice with APOE e2, APOE e3, or no APOE gene, suggesting that the virus could be replicating faster in the e4 mice. "The results definitely suggest there's something different about having APOE e4," says Dr. Federoff.
Still other research shows the direct impact of HSV-1 itself. In 2007, a study by Itzhaki and Wozniak found that infecting lab samples of brain cells with the virus caused a buildup of the protein (beta amyloid) that's the primary component of the plaque clogging the brains of Alzheimer's patients. The same study also found a similar result in the brains of mice that had been infected with HSV-1.
Then there was January's study in the Journal of Pathology. In it, Itzhaki and Wozniak looked at brain samples from 11 deceased people; six had had Alzheimer's and five hadn't. While both groups had plaques (not surprisingly, the Alzheimer's group had far more) and evidence of the herpes virus in their brains, there was a crucial difference in the concentration of the virus: In the Alzheimer's patients, 72 percent of the virus's DNA was found in the plaques, compared with only 24 percent that was found in the plaques of the non-Alzheimer's brains. Not surprisingly, all but one of the Alzheimer's sufferers also carried the APOE e4 gene, compared with none of the samples from the non-Alzheimer's people.
Wozniak is confident that these last two studies point to the same conclusion: "The results strongly suggest that HSV-1 is a major cause of amyloid plaques—and probably of Alzheimer's disease."
Most Popular in Health
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Health-conscious and environmentally aware consumers have been opting for veggie burgers in lieu of beef for years now, but a common industrial method of processing soybeans involves the use of hexane, a neurotoxin and registered air pollutant.
That's probably not what the typical veggie-burger buyer is bargaining for. "A lot of people who eat veggie burgers are doing so because they're conscious of their food choices and the impact on the environment," says Charlotte Vallaeys, Farm and Food Policy Analyst for The Cornucopia Institute, a sustainable-farming advocacy group. "But companies are either promoting themselves as natural or even 'made with organic' ingredients and then using hexane."
Vallaeys' report investigating the questionable soy processing procedures used to produce some soy veggie burgers was released last year, but a recent Mother Jones article brought the issue back into the public eye. Vallaeys explains that in soy veggie burgers not qualified for the USDA-certified organic seal, food manufacturers generally douse whole soybeans in a hexane solvent bath to break down the bean, separating the oil from the proteins.
WHAT IT MEANS:
It is not clear whether any hexane remains in the food, but it is certainly released into the atmosphere. Vallaeys says food processors are among the worst emitters of the air contaminant. And aside from concerns about hexane, there are issues with how the soy is grown. In the United States, about 90 percent of the soy supply comes from genetically engineered crops, a relatively new food practice that has not been tested for its impact on human health. Some researchers have linked genetically engineered food to food allergies, digestive diseases, and even accelerated aging. Genetically engineered crops are manipulated to either produce their own pesticide inside the plant (which we wind up eating) or to withstand heavy dousing of pesticides that are linked to everything from learning problems in kids to diabetes and Parkinson's disease in adults.
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Early Learning Center
SPRINGFIELD ? The Illinois State Board of Education (ISBE) encourages families to establish and maintain good health and study habits as schools across the state open doors for the start of a new academic year. The onset of the school year provides a prime opportunity to review academic skills and implement positive habits and routines.
“Students need to arrive at school ready for new challenges and experiences,” said State Board of Education Chairman Gery J. Chico. “Families can help their children excel by developing habits that ensure children get enough sleep, a good breakfast and a dedicated study time and place. Most importantly, they can pass on a positive attitude about education. Learning doesn’t just happen during the school day but every moment adults spend with children.”
As students approach the new school year, families might start new bedtime hours for an easier transition during the first week of school. Setting aside a quiet dedicated study space, with good light and appropriate supplies, may help children focus as they do homework.
A review of academic skills before the start of the school year may also help students succeed in the classroom. Some ideas include:
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"A printed card means nothing except that you are too lazy to write to the woman
done more for you than anyone in the world. And candy! You take a box to Mother —
and then eat most of it yourself. A pretty sentiment."
-- Anna Jarvis, promoter of the establishment
of Mother's Day and expert guilt-trip giver
Mothers--we've all got ‘em. We wouldn't be here if it weren't for Mom!
The beginning of Mother's Day in this country began as a fringe suggestion by Julia Ward Howe, a Unitarian and Women's Rights Activist, in a Proclamation of Peace in 1870. And the world thought that she was batty! How right Howe was because many ancient cultures including the Greek, Romans, and Celtics commemorated mother and creation with celebrations.
Text on OTRCAT.com ©2001-2010 OTRCAT INC All Rights Reserved-Reproduction is prohibited.
During the turn of the century Anna Jarvis picked up the fight to celebrate Mothers in the United States and dedicated her life to writing letters and influencing people to celebrate their mothers. It was quite a feat and in 1908 Nebraska Senator and Mom-lover, Elmer Burkett, suggested that the congress pass a resolution to establish Mother's Day, but it was defeated. Many senators were reminded by their moms about the 20 hours of labor they went through to bring the future law makers into the world for this, but it took another 6 years to establish a National Mother's Day! The resolution was signed in 1914 by President Woodrow Wilson to celebrate the Mom. Mama Wilson cheered as did the rest of the world.
This collection includes old time radio shows with moms of all sorts—pretty mamas, sweet mamas, mama's boys, unbearable and murderous mamas-in-laws.
Thank you to Moms Everywhere!
(Mother's Day is always the second Sunday in May.)
See also: Crazy Mamas and Father's Day Collection
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Functional diversity in marine ecosystems
Functional diversity refers to the variety of biological processes, functions or characteristics of a particular ecosystem in this case marine biodiversity.
Functional diversity reflects the biological complexity of an ecosystem. Some scientists argue that examining functional diversity may in fact be the most meaningful way of assessing biodiversity while avoiding the difficult and usually impossible task of cataloging all species in marine ecosystems. By focusing on processes, it may be easier to determine how an ecosystem can most effectively be protected. Protecting biological functions will protect many of the species that perform them. However, the exact function of most of the species is hardly known to date.
There are several ways in which ecological classifications group organisms according to common functions: classification according to their habitat, to their position in the food web or to their functional feeding mechanism.
Classification by ‘habitat’
Aquatic organisms can be divided into four major groups: pelagic, benthic, neuston and fringing, according to the water body which they inhabit.
For the Coastal Wiki there are eleven sub-categories:
Pelagic organisms are those that live in ocean water and are not associated with the bottom. They thus inhabit the water column and can be divided into plankton and nekton. Plankton are organisms that are suspended, (they float or are weakly self-propelled) in the water and drift with it as it moves. Plankton is either passive and includes algae, bacteria and variety of animals. Plankton is usually subdivided in phytoplankton (photosynthethic organisms like algae) and zooplankton (animals), what refers to their ecological function. Plankton can also be subdivided in holoplankton and meroplankton. Holoplankton are permanent members, represented by many taxa in the sea. Meroplankton are temporary members, spending only a part of their life cycle in the plankton. They include larvae of anemones, barnacles, crabs and even fish, which later in life will join the nekton or the benthos. Meroplankton are very much a feature of the sea, particularly coastal waters, as the often sedentary adult forms of coastal species use their planktonic stage for dispersal. Nekton are organisms swimming actively in the water, it includes a variety of animals, mostly fish.
Benthos comprises organisms on the bed of the water body. Animals attached to or living on the bottom are referred to as epifauna, while those which burrow into soft sediments or live in spaces between sediment particles are described as infauna.
Attached multicellular plants and algae are referred to as macrophytes, while single-celled or filamentous algae are called as periphyton or microphytobenthos. Epiphytic algae are those which grow on macrophytes. Benthic consumers can be divided by size into macrofauna (>500 μm), meiofauna (10-500 μm) and micro-organisms (<10 μm).
Neuston are those organisms associated with the water surface, where they are supported by surface tension. Most neuston require very still water surface and is therefore very restricted in the sea.
Fringing communities are floral communities that occur where the water is shallow enough for plentiful light to reach the bottom, allowing the growth of attached photosynthesisers, which may be entirely submerged or emergent into the air. Marine communities are composed mostly out of algal seaweeds. Wetlands are composed of this type of vegetation.
There are a lot of other habitat classifications, for example the EUNIS Habitat types classification.. This is a comprehensive pan-European system to facilitate the harmonized description and collection of data across Europe through the use of criteria for habitat identification; it covers all types of habitats from natural to artificial, from terrestrial to freshwater and marine.
An example of the EUNIS habitat classification: marine habitats at level 1 is the following:
- Littoral rock and other hard substrata
- Littoral sediment
- Infralittoral rock and other hard substrata
- Circalittoral rock and other hard substrata
- Sublittoral sediment
- Deep-sea bed
- Pelagic water column
- Ice-associated marine habitats
Classification by position in the food web
It is very difficult to make generalizations about the trophic relationships in coastal marine systems, because the ecological habitats are so diverse. A simplified description of a food web: the phytoplankton are the primary producers and are eaten by the zooplankton (smallest floating animals). The zooplankton are eaten by small fish (sardines, herring) and small fish are eaten by larger fish. At the top of the marine food web are the large predators (tuna, seals, sea-birds and some species of whales).
Phytoplankton, small zooplankton and large zooplankton, larger animals and top predators all interact in a marine food web. Each species eats and is eaten by several other species at different trophic levels.
The interactions in a food web are far more complex than the interactions in a food chain. Furthermore, the branching structure of food webs leads to fewer top predators compared with the numbers of top predators in a food chain.
In the microbial loop, bacteria consume Dissolved Organic Material (DOM) that cannot be directly ingested by larger organisms. DOM includes liquid wastes of zooplankton and cytoplasm that leaks out of phytoplankton cells. Bacteria are eaten by microflagellates. Ciliates, which are small enough to eat microflagellates, are eaten by zooplankton. Micro-flagellates and ciliates help to recycle organic matter back into the marine food web. Bacteria also help to facilitate phytoplankton growth by releasing nutrients when they absorb DOM. Viruses are the smallest and most abundant organisms in the sea, viral activity produces DOM, thus helping to drive energy cycles for ocean life. The main difference of the microbial loop between estuarine and coastal waters is that coastal waters tend to have lower population densities of bacteria and of the organism that prey on them.
Classification by functional feeding mechanism
There is a classification with several groups for marine and coastal systems:
- grazer-scrapers feed upon attached algae
- scavengers eat coarse particulate organic matter (detritus retained by a 1 mm sieve)
- collectors eat fine particulate organic matter (detritus passing through a 1 mm sieve but retained by 0.45 mm sieve)
- suspension or filter feeders remove particles from the watercolumn
- deposit feeders pick particles from the ocean bed
- predators consume other living animals
- parasites derive their food from a living organism of another species (host), they usually live in or on the body of the host.
In practice this distinction is very imprecise but useful as long as it is understood that they should not be too rigidly applied. The shelf bottom is occupied by diverse groups of benthic organisms that vary with changes in the bathymetry and sediment cover of the sea bed. For example gravel and coarse sand bottoms are mostly populated by filter feeders and fine sand bottoms are predominantly composed of deposit feeders. Muddy substrates are almost exclusively inhabited by deposit and detritus feeders.
COASTAL PELAGIC COMMUNITIES
In pelagic communities the classification based on feeding mechanism is less successful because consumers are opportunistic and will eat anything that is the correct size for their mouthparts to deal with.
Nekton are almost exclusively predators. The smaller species like the zooplankton are both predators and grazers. Plankton are therefore also classified by size, although there is again an overlap as many species will change to a larger size class as they grow older.
Loss of functional diversity of fish due to intense fishing causing ecosystem-wide effects in Mediterranean sublittoral rocky reefs
- ↑ Thorne-Miller Boyce (1999) The living ocean: understanding and protecting marine biodiversity. United States of America 213p
- ↑ 2.0 2.1 2.2 2.3 Dobson M. and Frid C. (1998). Ecology of aquatic systems. Addison Wesley Longman Limited: Edingburgh, (England). p222
- ↑ http://eunis.eea.europa.eu/habitats.jsp
- ↑ http://oceanworld.tamu.edu
- ↑ From "Fishing down marine food webs' as an integrative concept" by Daniel Pauly (University of British Columbia, Canada), Proceedings of the EXPO'98 Conference on Ocean Food Webs and Economic Productivity, online at the Community Research and Development Information Page
- ↑ http://www.bigelow.org
- ↑ http://www.waterencyclopedia.com/images
Please note that others may also have edited the contents of this article.
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The unique design of Literature & Thought provides the literature and teaching support you need to meet the challenges of the Common Core English Language Arts curriculum.
Close reading strategies
Writing to sources
Appropriate text complexity
Academic vocabulary support
Text dependent questions and tasks
Essential questions (whole book) and cluster questions (units) focus on developing specific critical thinking skills through careful reading,
textual analysis, discussion, and writing activities.
Outstanding literature and content-rich nonfiction and informational texts engage student's interest and focus attention on the critical thinking questions.
Selections provide the text complexity and academic vocabulary required by the Common Core State Standards (CCSS).
NEW! Professional learning—interactive online courses with experts from the Great Books Foundation in close reading of literary texts, strategic reading of informational texts, and more are included with each Teacher Package.
NEW! Interactive whiteboard lessons—explicit modeling and instruction of critical thinking and reading skills, writing rubrics, and much more.
NEW! Expanded Teacher Guides—informational text strategies, citing evidence to support analyses and claims, practice with academic vocabulary, specific support for CCSS in each selection (including detailed CCSS correlations), and multiple assessment options.
Great Books Discussion Guides for Teachers—specific questioning strategies developed by the Great Books Foundation supporting close text reading and discussion.
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The Onions are the nests of the Pikmin. Olimar named them so because of their resemblance to a vegetable native to his home planet. These bulbous plant-hives have brightly colored bodies with a black and white band across the midsection. At the spots the Onions land at the start of each day, there are concentric circles on the ground, which are never referred to in-game. Three stilt-like legs suspend the Onions out of the reach of hungry predators, and provide access to the inside for Pikmin. In Pikmin, Olimar states that he inspected the Onion's legs, and saw they were covered with tiny little hairs. There are three known types of Onion, each with unique coloration corresponding to either Red, Yellow or Blue Pikmin, and only one of each has ever been seen. Subterranean Pikmin species such as Purple Pikmin, White Pikmin and Bulbmin do not have Onions, or at least none that have yet been discovered.
During the daytime, Pikmin hunt and bring food, such as pellets or slain beasts, to the Onion, which in turn produces new Pikmin seeds. If there are fewer than 100 Pikmin on the field, the seeds are ejected and take root in the ground; if not, they are stored inside the Onion, along with any other Pikmin not on the field. When night falls and all the Pikmin have returned, the Onion folds its legs and lifts off from the ground, presumably using its flower petals like rotor blades to propel itself into the low atmosphere, where it hovers until daybreak. If an Onion loses all its Pikmin, it will produce a single seed the following day to prevent extinction.
When the Onions are first discovered in Pikmin, they are dormant. They have a dark grayish color, are flowerless, and their legs are buried in the ground until Olimar comes upon them, at which point they spring to life and spit out a single seed. It is not known exactly what triggers this hibernation.
In Pikmin 3, a mechanical spherical object with legs that resembles an Onion is shown. However, it isn't confirmed what this object does.
Red Onion
The Red Onion is the first Onion to be discovered in both games. In Pikmin, the Red Onion is found at The Impact Site, dormant in the ground not far from where the S.S. Dolphin crashed. Once awakened, it will release a single Red Pikmin seed which Olimar can use to harvest nearby red Pellet Posies and spawn enough Pikmin to retrieve the Main Engine. In Pikmin 2, Louie finds this Onion in the Valley of Repose when he falls out of the Ship's cockpit and gets lost.
Yellow Onion
The second Onion the player will come across in both games. In Pikmin, it is found dormant in The Forest of Hope amidst several yellow Pellet Posies and free-standing yellow pellets. In Pikmin 2, the Yellow Onion is located in the Perplexing Pool behind a poison gate protected by a Fiery Bulblax, so White Pikmin and Red Pikmin are required to reach it. There are a few yellow Pellet Posies nearby which will not regrow once they've been harvested.
Blue Onion
In Pikmin, it can be found in The Forest Navel in a pool near the landing site, and is the third Onion the player discovers. Several blue Pellet Posies are in the immediate vicinity, as well as a free-standing blue 5 pellet. In Pikmin 2, the Blue Onion is located in the Awakening Wood; although it can be seen relatively early in the game, it lies behind an electric gate, meaning that Yellow Pikmin from the Perplexing Pool are required to access it. A small pool blocks the only direct path up to the gate, so the Pikmin must be thrown onto a nearby ledge (while taking care not to disturb the Cloaking Burrow-nit lying in wait there). The Captain can then walk around through some water to reach them, and order them to defeat the beast and demolish the gate, allowing him to find the game's first 5 Blue Pikmin.
For some unknown reason, when landing on an area, the Blue Onion seems to hover a bit before landing, therefore landing slower than the Red Onion and Yellow Onion.
At the end of Pikmin, there is a rather confusing part where fourteen Onions, of colors that have not appeared in a Pikmin game so far, fly above the Planet of the Pikmin. It is unknown whether they are trying to follow Captain Olimar or merely hovering for the night. This could mean that more colors may yet be introduced in Pikmin 3. Interestingly, one of the Onions seen is purple, and Purple Pikmin were indeed introduced in Pikmin 2, but without an Onion.
In Super Smash Bros. Brawl
In Brawl, the three Onions appear as a trophy and on the "Distant Planet" stage. Here, when a pellet is thrown into one, an item is ejected. The number on the pellet thrown is the amount of items that will appear. More items will appear if the pellet and Onion have the same color, similar to the way it works in the Pikmin games. The Onions can also be hit, and will eventually fly away.
Brawl Trophy Description
"Items considered to be the places where Pikmin are born. As to the actual biology of the process, much is still unclear. Onions absorb the prey that Pikmin capture and use it to produce new Pikmin. In addition, Onions can take in Pikmin and later release them. These organisms are crowned with distinctive propeller-like sets of leaves that spin around, enabling them to fly."
- For the music in the Forest of Hope, at some points, the propeller petals of an Onion can be heard.
- When Olimar first came upon the Red Onion in Pikmin, he was knocked over by one of the legs as it sprang out of the ground. When he finds the other two later on in the game, he is a little more cautious and backs away.
- If, on a day where Olimar or Louie finds an Onion, and enters a cave after whistling the wild Pikmin, the Onion will be at the landing site when the cave is left.
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Although Diesel was born in Paris, his parents were German. His father was a leather craftsman, and his mother a governess and language tutor.
Rudolf was a good student in primary school and was admitted at the age of 12 to the Ecole Primaire Superieure, then regarded as the best in Paris. On the outbreak of the Franco-Prussian War, however, he and his parents were considered enemy aliens, and were deported to neutral asylum in London. A cousin helped him to return to his father's home town, Augsburg, where he entered the Royal County Trade School. From there he won a scholarship to the Technische Hochschule of Munich, where he was an outstanding student. He became a protegé of Carl von Linde, the pioneer of refrigeration. He was a devout Lutheran.
After graduation, he was employed for two years as a machinist and designer in Winterthur, Switzerland. After this, he returned to Paris, where he was employed as a refrigeration engineer at Linde Refrigeration Enterprises. In Paris he became a connoisseur of the fine arts and an internationalist. He married in 1883, and had three children. He set up his first shop-laboratory in 1885 in Paris, and began full-time work on his engine. This continued when he moved to Berlin, working again for Linde Enterprises. In 1892 he was granted a German patent for the engine, and found some support for its continued development, this time in Augsburg.
Rudolf Diesel developed the idea of an engine that relied on a high compression of the fuel to ignite it, eliminating the spark plug used in the Nikolaus Otto internal combustion engine. He received a patent for the device on February 23, 1892 and a major milestone was achieved when he was able to run a single piston engine for one minute on February 17, 1894. The engine was fueled by powdered coal injected with compressed air. This machine stood 10 feet (3 m) tall, and achieved a compression of 80 atmospheres (8100 kPa). He built an improved prototype in early 1897 while working at the Maschinenfabrik Augsburg (from 1906 on the MAN) plant at Augsburg. Diesel's engine had some similarities with an engine invented by Herbert Akroyd Stuart in 1890. Diesel was embroiled for some years in various patent disputes and arguments over priority, but in the end he prevailed, and his invention came to be called the diesel engine. He continued its development over the next three years, began production (the first commercial engine was at a brewery in the United States), and secured licenses from firms in several countries. He became a millionaire.
Diesel was something of an unstable character, having several nervous breakdowns, and was somewhat paranoid at times. He defended his priority of invention tenaciously. Diesel toured the United States as a lecturer in 1904, and he self-published a two volume work on his social philosophy. He died under suspicious circumstances during a crossing of the English Channel to Harwich on September 29, 1913, possibly by suicide. A cross in his journal on the date he died was an indicator of suicide. A briefcase containing a very small sum of money and a large amount of bank statements showing debts, was left to his wife, Martha. Another theory revolves around the German Military, which was beginning to use his engines on their submarines—something which Mr. Diesel opposed—and perhaps feared his potentially providing the technology to the British Royal Navy for use in their own submarines. His body was found in the Channel a few days later. As was usual at the time, the seamen only took his belongings (identified later by Diesel's younger son Eugen) and then threw the body back into the sea.
After Diesel's death, the diesel engine underwent much further development, and became a very important replacement for the steam engine in many applications. This engine required a heavier, more robust construction than the gasoline engine, making it unsuitable for certain applications (such as aviation), but allowed the use of cheaper fuels. Diesel was especially interested in using coal dust or vegetable oil as fuel for the engine, but this never materialized in any major way, at least until recent rises in fuel prices and concerns about oil reserves lead to more widespread use of vegetable oil and biodiesel—most Diesel engines will function just as well using either. But the primary source of fuel has been what became known as diesel fuel, an oil byproduct derived from the refining of petroleum. The Diesel engine became widespread in many other applications, such as stationary engines, submarines, ships, and much later, locomotives.
Recently, Diesel engines have been designed, certified and flown that have overcome the weight penalty in light aircraft. These engines are designed to run on either diesel fuel or more commonly Jet fuel.
Info by Wikipedia
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I recently watched a BBC documentary entitled Out of Africa, a five-part series chronicling the migration of Homo sapiens out of Africa and into Asia, Australia, Europe, and the Americas. Although all five parts were fascinating, I was particularly rapt by the arrival of Homo sapiens (modern humans) into Europe some 40,000 years ago after a 70,000 year trek out of Africa, only to discover that Neanderthals, a proto-human and distant cousin had arrived some 100,000 years earlier. Neanderthals were a heartier, huskier species than Homo Sapiens, had a larger brain and more advanced technology, and had long since adapted to harsh European winters. However, 20,000 years or so later, Neanderthals had died out — completely. To this day, no Neanderthal genetic markers have been found in modern humans.
How is it possible that a physically more powerful, better environmentally adapted, and technologically more advanced proto-human did not survive, while Homo sapiens, the weaker, less advanced interloper, not only survived but burgeoned to eventually populate the entire globe and create the marvelously modern societies of today?
Paleoanthropologists hot on the Homo sapien trail out of Africa have discovered in Europe a marked difference between Homo sapiens and Neanderthals: Homo sapiens may not have produced better weapons and tools, at least then, but they did make a quantum leap to produce art. They carved, pottered, sculpted, painted, and even made musical instruments, all with an eye on style rather than just making meaningless pretty. More importantly, their art embodied and transmitted — as art does — their identity, spirituality, and, their strong affinity for community.
Early Homo sapien art strongly suggests that our predecessors engaged in an intellectual endeavor to create a unique and dynamic culture and to communicate that culture through art. Homo sapien civilization, it seems, was predicated on the notion that life must be more than just survival, and that working together to survive allowed room for higher pursuit. Conversely, there is no evidence of this intellectual “artsy” undertaking among Neanderthals, who seem to have clung to a strictly utilitarian life for survival, which, ironically, led to their extinction when Europe became encased in 13 feet of ice.
Because Homo sapiens had cultivated a common cultural bond and strong communal ties, they were able to come together and huddle together, literally and figuratively, and, although large numbers perished during the Ice Age, enough adapted to a starkly altered environment and survived to carry on to become “us.” Neanderthals, on the other hand, were literally and figuratively left out in the cold — to perish everlastingly.
The inevitable machinations of evolution are tied up in minute and initially imperceptible changes over vast stretches in time to produce an optimum species. Our ancient ancestors, Homo sapiens, and their distant cousins, Neanderthals, hardly understood the long-term repercussions of their actions because they did not have the benefit of eons and eons of the recorded “heart and mind” of humankind nor the technology to access it. They could not look back thousands, hundreds of thousands, and millions of years and make decisions about their survival and their future based on that knowledge. But we can — and like it or not, we are a global community and our well-being and survival will likely depend upon our ability to indiscriminately come together and “huddle” together against adversity.
But make no mistake about it, whatever path humankind chooses, evolution will be our judge about whether or not we chose wisely.
Photo Credit: Wikimedia Commons
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Geoscience experts have developed a system of smart buoys that can predict the formation of self-reinforcing underwater waves, or solitons, 10 hours before they threaten the safety of oil rigs and divers. In 2008, Martin Goff and his colleagues at FUGROS, a geoscience consulting agency, successfully tested the system for three months in the Andaman Sea. Now, Global Ocean Associates have acknowledged the device as "the first deployed system with real-time warning capability."
Scientists discover ancient rocks on the sea-floor that give them a window into the Earth's mantle
By Gregory Mone
Posted 04.14.2008 at 8:28 am 0 Comments
No, you can't hike or spelunk or even tunnel down to the center of the Earth, even if movies like The Core or this summer's 3D adventure flick, Journey to the Center of the Earth, suggest otherwise. To find out about our planet's insides, scientists rely on very different tricks. And, apparently, a little luck.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.
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Growing Older, Driving Safely
Safe driving requires complex visual processing – abilities that may begin to decline as we age. A loss in your visual abilities could endanger you and others on the road. But you can maintain your independence and drive safely longer if you:
1. Get a complete eye exam regularly,
2. Know the vision issues that can affect your driving,
3. Understand the laws in your state about driving as you age, and
4. Talk to your eye doctor about maintaining your fitness to drive
It is important to note that visual processing is but one component of safe driving. Other key factors include 1) the motor ability to scan rapidly changing environments; 2) the sensory ability to perceive information in a rapidly changing environment; 3) the attentiveness to process multiple pieces of information; and 4) the cognitive and motor ability to judge information in a timely fashion and to make appropriate decisions.
Know the Law in Your State ► Know the Law in Your State ▼
Vision and Driving
Visual Acuity ► Visual Acuity ▼
Visual acuity makes it possible for you to notice moving and still objects that you must see, and often notice quickly, to make safe driving decisions. With good acuity, you can read traffic signs, street names, and addresses at a distance with time to react safely to conditions. You also rely on your visual acuity to see any object or hazard on or near the road.
Vision in Low Contrast Situations ► Vision in Low Contrast Situations ▼
Low-contrast visual acuity lets you see and drive safely in rain, snow, fog, or at dusk. Objects do not always stand out clearly from their surroundings, such as potholes, cars without lights on at dusk, pedestrians crossing in front of you in the rain, and almost anything at night not directly in range of your headlights. When your visual acuity for low contract objects decreases, you may not be able to see potential dangers soon enough to respond safely.
Keeping Track of Visual Information ► Keeping Track of Visual Information ▼
When driving, you must scan your surroundings constantly for potential conflicts with other road users. At the same time, you must pay attention to road features like traffic signs and signals, and landmarks or other information that helps you find your way as you drive. This is most important at intersections, where the majority of serious crashes occur. When you are about to start moving after a traffic light turns green, you look to your left and right and then across the intersection in the direction you’re driving. Being able to locate safety threats quickly and make immediate driving decisions based on information from many different places is a critical part of driving.
What you are aware of in your field of view, and how quickly you become aware of it, can determine whether or not you can drive safely and avoid crashing at an intersection, a shopping center parking lot, or in any driving situation. If your ability to keep track of and process visual information decreases with age, you may have problems identifying and reacting to safety threats.
Visit an eye doctor regularly ► Visit an eye doctor regularly ▼
One very important thing you can do to make sure you can drive safely longer is get your eyes checked regularly by an eye doctor—at least once every other year—if you are 55 or older. You should visit your eye doctor even if you have no problems seeing, and talk to your eye doctor about driving and your vision.
Budget for proper eye care ► Budget for proper eye care ▼
You should budget for the cost of a regular eye exam at least every other year or more frequently if your doctor recommends it. Most people want to protect their vision and ability to maintain independence (including driving), even it if involves a cost. Proper eye care doesn't have to be expensive. Think of it as an investment in good vision and in your quality of life.
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Intracranial tumors comprise approximately 2% of all adult cancers, but form a larger fraction within the group of childhood tumors. Gliomas account for approximately 60% of all intracranial tumors and are classified according to the suggested cell of origin, differentiation and malignancy grade. The prognosis for high-grade gliomas is poor due to limited possibilities of curative treatment.
Gliomas are tumors of neuroepithelial tissue and comprise a complex and heterogeneous group of tumors representing counterparts to various normal inhabitant cells of the central nervous system (CNS). The most common form of glioma is astrocytoma, representing approximately one third of all gliomas.
Astrocytomas are defined based on morphological features such as cellularity, nuclear atypia, mitotic rate, endothelial proliferation and necrosis, and assigned to grades I-IV according to the current WHO classification system. These include pilocytic astrocytoma (Grade I), astrocytoma (Grade II), anaplastic astrocytoma (Grade III), and glioblastoma (Grade IV). The various forms of glioma are highly vaiable and several phenotypically different cell types exist, including gemistocytic glioma cells. Gemistocytic cells resemble a morphological alteration that can also be found in reactive astrocytes and is characterized by eosinophilic staining of a large, swollen cytoplasm.
Approximately 15% of gliomas are oligodendrogliomas. Histologically, oligodendrogliomas commonly show uniform cell architecture with increased numbers of delicate blood vessels. The tumor cell nuclei are mainly round and regular, and often surrounded by an artifactual perinuclear clearing that results in the so called ?fried egg? appearance. High-grade oligodendrogliomas (anaplastic oligodendrogliomas) are recognized by features such as increased cellularity, mitotic activity and nuclear pleomorphism, as well as necrosis and endothelial proliferation.
Additional forms of glioma include mixed gliomas such as oligoastrocytoma and ependymal tumors. Examples of other neuroepithelial tumors that grow within the CNS are neuronal and mixed neuronal-glial tumors, as well as embryonal tumors including neuroblastoma and medulloblastoma.
The distinction between different forms of brain tumors is mainly based on morphological features, but immunohistochemistry plays an important role to distinguish between different tumor types, in particular when the tumor is poorly differentiated. In neuropathological diagnostics, antibodies directed towards proteins such as Glial Fibrillary Acidic Protein, Synaptophysin, EGFR, p53 and the proliferation marker Ki-67 are commonly used.
Normal tissue: Cerebral cortex
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Why Argue? Helping Students See the Point
Read the comments on any website and you may despair at Americans’ inability to argue well. Thankfully, educators now name argumentive reasoning as one of the basics students should leave school with.
But what are these skills and how do children acquire them? Deanna Kuhn and Amanda Crowell, of Columbia University’s Teachers College, have designed an innovative curriculum to foster their development and measured the results. Among their findings, published in Psychological Science, a journal of the Association for Psychological Science, dialogue is a better path to developing argument skills than writing.
“Children engage in conversation from very early on,” explains Kuhn. “It has a point in real life.” Fulfilling a writing assignment, on the other hand, largely entails figuring out what the teacher wants and delivering it. To the student, “that’s its only function.”
Kuhn and Crowell conducted a three-year intervention at an urban middle school whose students were predominantly Hispanic, African-American, and low-income. Beginning in sixth grade, two classes totaling 48 children participated; a comparison group of 23 were taught in a more conventional way.
Each year comprised four 13-class segments. Each quarter, the students entertained one social issue—beginning with subjects close to their lives, such as school discipline, and proceeding to issues of broader social consequence, such as abortion and gun control. Choosing their sides and working in groups, students prepared for debate—enumerating and evaluating reasons for their beliefs, surmising opponents’ arguments, and considering counterarguments and rebuttals. Then, pairs of same-side students debated opposing pairs.
In years two and three, participants were asked during each cycle to generate questions whose answers would help them make their arguments—a way of promoting their appreciation of evidence. Soon, they not only generated many questions but also volunteered to research the answers.
The debates took place via computer—another innovation of the intervention—so the dialogue remained on the screen, promoting reflection. The cycle culminated in a lively “showdown” between the teams, in which students individually took the “hotseat” debating an opponent but could turn to their teammates for tactical “huddles.” Finally, students wrote individual essays justifying their positions on the topic.
The comparison class engaged in full-class teacher-led discussions of similar topics and wrote essays—14 annually compared to the intervention groups’ four.
Before the intervention and after each year, all students wrote essays on entirely new topics. The researchers analyzed these for the kinds and number of arguments—those focused on the virtues of one’s own side; those addressing the opposing side (“dual perspective”); and those attempting to weigh pros and cons of each side (“integrative perspective”). They also looked at the questions the students would like answers to.
On each count, the experimental group did better, making more of the higher forms of arguments and listing more questions of substance than the control group.
Crucially, says Kuhn, the children embraced a core value of citizenship: informed argument matters. They expressed it too. “We have gotten a little complaint from nearby classrooms that it’s a bit noisy,” she adds.
For more information about this study, please contact: Deanna Kuhn at [email protected].
The APS journal Psychological Science is the highest ranked empirical journal in psychology. For a copy of the article "Dialogic Argumentation as a Vehicle for Developing Young Adolescents’ Thinking" and access to other Psychological Science research findings, please contact Tiffany Harrington at 202-293-9300 or [email protected].
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Using an ultra-bright electron source, scientists at the University of Toronto have recorded atomic motions in real time, offering a glimpse into the very essence of chemistry and biology at the atomic level. Their recording is a direct observation of a transition state in which atoms undergo chemical transformation into new structures with new properties.
Using a new tool called a quantum simulator—based on a small-scale quantum computer—...
A massive telescope buried in the Antarctic ice has detected 28 extremely high-energy...
A fried breakfast food popular in Spain provided the inspiration for the development of doughnut-shaped droplets that may provide scientists with a new approach for studying fundamental issues in physics, mathematics, and materials. The doughnut-shaped droplets, a shape known as toroidal, are formed from two dissimilar liquids using a simple rotating stage and an injection needle.
The massive ball of iron sitting at the center of Earth is not quite as "rock-solid" as has been thought, say two Stanford University mineral physicists. By conducting experiments that simulate the immense pressures deep in the planet's interior, the researchers determined that iron in Earth's inner core is only about 40% as strong as previous studies estimated.
Graphene has dazzled scientists ever since its discovery more than a decade ago. But one long-sought goal has proved elusive: how to engineer into graphene a property called a band gap, which would be necessary to use the material to make transistors and other electronic devices. New findings by Massachusetts Institute of Technology researchers are a major step toward making graphene with this coveted property.
With the hand of nature trained on a beaker of chemical fluid, the most delicate flower structures have been formed in a Harvard University laboratory—and not at the scale of inches, but microns. These minuscule sculptures, curved and delicate, don't resemble the cubic or jagged forms normally associated with crystals, though that's what they are. Rather, fields of flowers seem to bloom from the surface of a submerged glass slide.
A new joint innovation by the National Physical Laboratory and the University of Cambridge could pave the way for redefining the ampere in terms of fundamental constants of physics. The world's first graphene single-electron pump provides the speed of electron flow needed to create a new standard for electrical current based on electron charge.
Described as the "most beautiful experiment in physics," Richard Feynman emphasized how the diffraction of individual particles at a grating is an unambiguous demonstration of wave-particle duality and contrary to classical physics. A research team recently used carefully made fluorescent molecules and nanometric detection accuracy to provide clear and tangible evidence of the quantum behavior of large molecules in real time.
Bubble baths and soapy dishwater and the refreshing head on a beer: These are foams, beautiful yet ephemeral as the bubbles pop one by one. Now, a team of researchers has described mathematically the successive stages in the complex evolution and disappearance of foamy bubbles, a feat that could help in modeling industrial processes in which liquids mix or in the formation of solid foams such as those used to cushion bicycle helmets.
An international team of physicists has found the first direct evidence of pear-shaped nuclei in exotic atoms. The findings could advance the search for a new fundamental force in nature that could explain why the Big Bang created more matter than antimatter—a pivotal imbalance in the history of everything.
From powerful computers to super-sensitive medical and environmental detectors that are faster, smaller, and use less energy—yes, we want them, but how do we get them? In research that is helping to lay the groundwork for the electronics of the future, University of Delaware scientists have confirmed the presence of a magnetic field generated by electrons which scientists had theorized existed, but that had never been proven until now.
Physicists working with optical tweezers have conducted work to provide an all-in-one guide to help calculate the effect the use of these tools has on the energy levels of atoms under study. This effect can change the frequency at which atoms emit or absorb light and microwave radiation and skew results; the new findings should help physicists foresee effects on future experiments.
Physicists in Switzerland have demonstrated one of the quintessential effects of quantum optics—known as the Hong-Ou-Mandel effect—with microwaves, which have a frequency that 100,000 times lower than that of visible light. The experiment takes quantum optics into a new frequency regime and could eventually lead to new technological applications.
The allure of personalized medicine has made new, more efficient ways of sequencing genes a top research priority. One promising technique involves reading DNA bases using changes in electrical current as they are threaded through a nanoscopic hole. Now, a team led by University of Pennsylvania physicists has used solid-state nanopores to differentiate single-stranded DNA molecules containing sequences of a single repeating base.
An international research team led by astronomers from the Max Planck Institute for Radio Astronomy used a collection of large radio and optical telescopes to investigate in detail a pulsar that weighs twice as much as the sun. This neutron star, the most massive known to date, has provided new insights into the emission of gravitational radiation and serves as an interstellar laboratory for general relativity in extreme conditions.
Using uniquely sensitive experimental techniques, scientists have found that laws of quantum physics—believed primarily to influence at only sub-atomic levels—can actually impact on a molecular level. The study shows that movement of the ring-like molecule pyrrole over a metal surface runs counter to the classical physics that govern our everyday world.
In a process comparable to squeezing an elephant through a pinhole, researchers at Missouri University of Science and Technology have designed a way to engineer atoms capable of funneling light through ultrasmall channels. Their research is the latest in a series of recent findings related to how light and matter interact at the atomic scale.
Cancer cells that can break out of a tumor and invade other organs are more aggressive and nimble than nonmalignant cells, according to a new multi-institutional nationwide study. These cells exert greater force on their environment and can more easily maneuver small spaces.
One simple phenomenon explains why practical, self-sustaining fusion reactions have proved difficult to achieve: Turbulence in the superhot, electrically charged gas, called plasma, that circulates inside a fusion reactor can cause the plasma to lose much of its heat. This prevents the plasma from reaching the temperatures needed to overcome the electrical repulsion between atomic nuclei. Until now.
Lawrence Berkeley National Laboratory’s sound-restoration experts have done it again. They’ve helped to digitally recover a 128-year-old recording of Alexander Graham Bell’s voice, enabling people to hear the famed inventor speak for the first time. The recording ends with Bell saying “in witness whereof, hear my voice, Alexander Graham Bell.”
Researchers at University of California, Santa Barbara in collaboration with colleagues at the École Polytechnique in France, have conclusively identified Auger recombination as the mechanism that causes light-emitting diodes (LEDs) to be less efficient at high drive currents.
A Harvard University-led team of researchers has created a new type of nanoscale device that converts an optical signal into waves that travel along a metal surface. Significantly, the device can recognize specific kinds of polarized light and accordingly send the signal in one direction or another.
The planet-hunting Kepler telescope has discovered two planets that seem like ideal places for some sort of life to flourish. According to scientists working with the NASA telescope, they are just the right size and in just the right place near their star. The discoveries, published online Thursday, mark a milestone in the search for planets where life could exist.
Throughout decades of research on solar cells, one formula has been considered an absolute limit to the efficiency of such devices in converting sunlight into electricity: Called the Shockley-Queisser efficiency limit, it posits that the ultimate conversion efficiency can never exceed 34% for a single optimized semiconductor junction. Now, researchers have shown that there is a way to blow past that limit.
Scientists in Australia have recently demonstrated that ultra-short durations of electron bunches generated from laser-cooled atoms can be both very cold and ultra-fast. The low temperature permit sharp images, and the electron pulse duration has a similar effect to shutter speed, potentially allowing researchers to observe critical but quick dynamic processes, such as the picosecond duration of protein folding.
A University of Missouri engineer has built a system that is able to launch a ring of plasma as far as two feet. Plasma is commonly created in the laboratory using powerful electromagnets, but previous efforts to hold the super-hot material through air have been unsuccessful. The new device does this by changing how the magnetic field around the plasma is arranged.
Physicists operating an experiment located half a mile underground in Minnesota reported this weekend that they have found possible hints of dark-matter particles. The Cryogenic Dark Matter Search experiment has detected three events with the characteristics expected of dark matter particles.
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A Close-Up View of Mercury's Colors
October 30, 2008
- Date Acquired: October 6, 2008
- Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
- Scale: The width of this scene is 620 kilometers (390 miles)
Of Interest: After MESSENGER made its closest approach to Mercury, flying just 200 kilometers (124 miles) above the surface, and as soon as the sunlit side of Mercury was fully in view, MDIS captured the highest-resolution color images ever obtained of Mercury (500 meters/pixel (0.3 miles/pixel)). This area was also seen by Mariner 10, whose lower-resolution two-color images hinted at the variety and nature of regions of different colors, and hence composition, on Mercury. Viewed here at high-resolution and in enhanced color, the relationship between the relatively young smooth plains on the left and older, dark blue material on the right is clear. The younger smooth plains cover the lower parts of rougher pre-existing topography and infill older craters, like the 120-kilometer (75-mile) diameter Rudaki crater lower-left of center. Dark, relatively blue material was ejected from the 105-kilometer (65-mile) diameter crater on the right side of the image, covering older smooth plains. A relatively young, small crater then excavated through this blue material to reveal the smooth plains beneath. This scene is centered at 4° South, 310° East and is outlined by a white rectangle on the enhanced color equatorial view of the side of Mercury seen during MESSENGER's second Mercury flyby.
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National Constitutional provisions – Philippines
The constitution is the fundamental law of the country, reflecting the underlying and unifying values of society. It spells out the basic rights of each person; it serves as a framework for all other laws and policies, and cannot be easily changed. However, it can be changed and updated through a democratic process, and it is important to keep it alive, by popularising and using it, and by campaigning for its reform or amendment if necessary. Below we have picked out what we see as some of the most relevant articles, but please be encouraged to seek and read your constitution in its entirety.
The state is the central actor in any claim to the right to education: it is the prime duty-bearer and the prime implementer; it is the guarantor; and it is the state´s signature vis-à-vis the international norms and standards which binds it to respect, protect and fulfil the right to education. The state must therefore be judged or challenged on its central text on the right to education, whether this be the constitution, the laws or the policies.
The Constitution of Philippines Adopted 15 October 1986, amended 1987
The State shall protect and promote the right of all citizens to quality education at all levels, and shall take appropriate steps to make such education accessible to all.
The State shall:
(1) Establish, maintain, and support a complete, adequate, and integrated system of education relevant to the needs of the people and society;
(2) Establish and maintain, a system of free public education in the elementary and high school levels. Without limiting the natural rights of parents to rear their children, elementary education is compulsory for all children of school age;
(3) Establish and maintain a system of scholarship grants, student loan programs, subsidies, and other incentives which shall be available to deserving students in both public and private schools, especially to the under-privileged;
(4) Encourage non-formal, informal, and indigenous learning systems, as well as self-learning, independent, and out-of-school study programs, particularly those that respond to community needs; and
(5) Provide adult citizens, the disabled, and out-of-school youth with training in civics, vocational efficiency, and other skills.
(3) At the option expressed in writing by the parents or guardians, religion shall be allowed to be taught to their children or wards in public elementary and high schools within the regular class hours by instructors designated or approved by the religious authorities of the religion to which the children or wards belong, without additional cost to the Government.
(2) Educational institutions, other than those established by religious groups and mission boards, shall be owned solely by citizens of the Philippines or corporations or associations at least sixty per centum of the capital of which is owned by such citizens. The Congress may, however, require increased Filipino equity participation in all educational institutions.
The control and administration of educational institutions shall be vested in citizens of the Philippines.
No educational institution shall be established exclusively for aliens and no group of aliens shall comprise more than one-third of the enrolment in any school. The provisions of this subsection shall not apply to schools established for foreign diplomatic personnel and their dependents and, unless otherwise provided by law, for other foreign temporary residents.
(2) Academic freedom shall be enjoyed in all institutions of higher learning.
(3) Every citizen has a right to select a profession or course of study, subject to fair, reasonable, and equitable admission and academic requirements.
(4) The State shall enhance the right of teachers to professional advancement. Non-teaching academic and non-academic personnel shall enjoy the protection of the State.
(5) The State shall assign the highest budgetary priority to education and ensure that teaching will attract and retain its rightful share of the best available talents through adequate remuneration and other means of job satisfaction and fulfillment.
(…) the Government shall take steps to initiate and sustain the use of Filipino as a medium of official communication and as a language of instruction in the educational system.
The State shall give priority to education [...]
No person shall be deprived of life, liberty, or property without due process of law, nor shall any person be denied the equal protection of the laws.
The State shall guarantee equal access to opportunities for public service, and prohibit political dynasties as may be defined by law.
The Congress shall give highest priority to the enactment of measures that protect and enhance the right of all the people to human dignity, reduce social, economic, and political inequalities, and remove cultural inequities by equitably diffusing wealth and political power for the common good. To this end, the State shall regulate the acquisition, ownership, use, and disposition of property and its increments.
(1) the State shall take into account regional and sectoral needs and conditions and shall encourage local planning in the development of educational policies and programs.
See Article 4 (very extensive).
The State recognizes the role of women in nation-building, and shall ensure the fundamental equality before the law of women and men.
The State shall protect working women by providing safe and healthful working conditions, taking into account their maternal functions, and such facilities and opportunities that will enhance their welfare and enable them to realize their full potential in the service of the nation.
The State shall adopt an integrated and comprehensive approach to health development which shall endeavor to make essential goods, health and other social services available to all people at affordable cost. There shall be priority for the needs of the underprivileged sick, elderly, disabled, women, and children. The State shall endeavor to provide free medical care to paupers.
The State shall establish a special agency for disabled persons for rehabilitation, self-development and self-reliance, and their integration into the mainstream of society
The national language of the Philippines is Filipino. As it evolves, it shall be further developed and enriched on the basis of existing Philippine and other languages.
Subject to provisions of law and as the Congress may deem appropriate, the Government shall take steps to initiate and sustain the use of Filipino as a medium of official communication and as language of instruction in the educational system.
For purposes of communication and instruction, the official languages of the Philippines are Filipino and, until otherwise provided by law, English.
The regional languages are the auxiliary official languages in the regions and shall serve as auxiliary media of instruction therein.
Spanish and Arabic shall be promoted on a voluntary and optional basis.
This Constitution shall be promulgated in Filipino and English and shall be translated into major regional languages, Arabic, and Spanish.
The Congress shall establish a national language commission composed of representatives of various regions and disciplines which shall undertake, coordinate, and promote researches for the development, propagation, and preservation of Filipino and other languages.
No law shall be made respecting an establishment of religion, or prohibiting the free exercise thereof. The free exercise and enjoyment of religious profession and worship, without discrimination or preference, shall forever be allowed. No religious test shall be required for the exercise of civil or political rights
The State recognizes the sanctity of family life and shall protect and strengthen the family as a basic autonomous social institution. It shall equally protect the life of the mother and the life of the unborn from conception. The natural and primary right and duty of parents in the rearing of the youth for civic efficiency and the development of moral character shall receive the support of the Government.
The State shall defend :
(1) The right of spouses to found a family in accordance with their religious convictions and the demands of responsible parenthood;
(2) The right of children to assistance, including proper care and nutrition, and special protection from all forms of neglect, abuse, cruelty, exploitation, and other conditions prejudicial to their development;
(3) The right of the family to a family living wage and income; and
(4) The right of families or family associations to participate in the planning and implementation of policies and programs that affect them.
The family has the duty to care for its elderly members but the State may also do so through just programs of social security.
HUMAN RIGHTS MECHANISMS
(1) There is hereby created an independent office called Commission on Human Rights. (2) The Commission shall be composed of a Chairman and four Members who must be natural-born citizens of the Philippines and a majority of whom shall be members of the Bar. The term of office and other qualifications and disabilities of the Members of the Commission shall be provided by law. (3) Until this Commission is constituted, the existing Presidential Committee on Human Rights shall continue to exercise its present functions and powers. (4) The approved annual appropriations of the Commission shall be automatically and regularly released.
The Commission on Human Rights shall have the following powers and functions: (1) Investigate, on its own or on complaint by any party, all forms of human rights violations involving civil and political rights; (2) Adopt its operational guidelines and rules of procedure, and cite for contempt for violations thereof in accordance with the Rules of Court; (3) Provide appropriate legal measures for the protection of human rights of all persons within the Philippines, as well as Filipinos residing abroad, and provide for preventive measures and legal aid services to the underprivileged whose human rights have been violated or need protection; (4) Exercise visitorial powers over jails, prisons, or detention facilities; (5) Establish a continuing program of research, education, ad information to enhance respect for the primacy of human rights; (6) Recommend to the Congress effective measures to promote human rights and to provide for compensation to victims of violations of human rights, or their families; (7) Monitor the Philippine Government's compliance with international treaty obligations on human rights; (8) Grant immunity from prosecution to any person whose testimony or whose possession of documents or other evidence is necessary or convenient to determine the truth in any investigation conducted by it or under its authority; (9) Request the assistance of any department, bureau, office, or agency in the performance of its functions; (10) Appoint its officers and employees in accordance with law; and (11) Perform such other duties and functions as may be provided by law.
The Congress may provide for other cases of violations of human rights that should fall within the authority of the Commission, taking into account its recommendations.
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Lake Hengstey is located near Hagen, downstream of the River Lenne’s mouth into the River Ruhr. When it was first put into operation, the chalybeate and acid Lenne waters mixed here with the alkaline waters of the River Ruhr, leading to increased sludge precipitation and creating a strong purification effect. Today, water quality of the Lenne water has been considerably improved thanks to the construction of wastewater treatment plants, and Lake Hengstey serves as a bed-load trap and fine screening step.
MMoreover, Lake Hengstey serves as a low-level reservoir for the pumped-storage hydrostation in Kerdecke (Koepchenwerk), built by the RWE energy corporation. Due to the pumped-storage mechanism, the water level of Lake Hengstey fluctuates by up to 70 centimetres. In 1988/89, approx. 400,000 cubic metres of sediment were dredged from Lake Hengstey.
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Knee osteotomy is surgery that removes a part of the bone of the joint of either the bottom of the femur (upper leg bone) or the top of the tibia (lower leg bone) to increase the stability of the knee. Osteotomy redistributes the weight-bearing force on the knee by cutting a wedge of bone away to reposition the knee. The angle of deformity in the knee dictates whether the surgery is to correct a knee that angles inward, known as a varus procedure, or one that angles outward, called a valgus procedure. Varus osteotomy involves the medial (inner) section of the knee at the top of the tibia. Valgus osteotomy involves the lateral (outer) compartment of the knee by shaping the bottom of the femur.
Osteotomy surgery changes the alignment of the knee so that the weight-bearing part of the knee is shifted off diseased or deformed cartilage to healthier tissue in order to relieve pain and increase knee stability. Osteotomy is effective for patients with arthritis in one compartment of the knee. The medial compartment is on the inner side of the knee. The lateral compartment is on the outer side of the knee. The primary uses of osteotomy occur as treatment for:
- Knee deformities such as bowleg in which the knee is varus-leaning (high tibia osteotomy, or HTO) and knock-knee (tibial valgus osteotomy), in which the knee is valgus leaning.
- A torn anterior cruciate ligament (ACL), which is a set of ligaments that connects the femur to the tibia behind the patella and offers stability to the knee on the left-right or medial-lateral axis. If this ligament is injured, it must be repaired by surgery. Many ACL injuries cause inflammation of the cartilage of the knee and result in bones extrusions, as well as instability of the knee due to malalignment. Osteotomy is performed to cut cartilage and increase the fit and alignment of the ends of the femur and tibia for smooth articulation. As one very common knee injury that often occurs in athletic activity, HTO is often performed when ACL surgery is used to repair the ligament. The combination of the two surgeries occurs primarily in young people who wish to return to a highly athletic life.
- Osteoarthritis that includes loss of range of motion, stiffness, and roughness of the articular cartilage in the knee joint secondary to the wear and tear of motion, especially in athletes, as well as cartilage breakdown resulting from traumatic injuries to the knee. Surgery for progressive osteoarthritis or injury-induced arthritis is often used to stave off total joint replacement.
After surgery, patients are placed in a hinged brace. Toe-touching is the only weight-bearing activity allowed for four weeks in order to allow the osteotomy to hold its place. Continuous passive motion is begun immediately after surgery and physical therapy is used to establish full range of motion, muscle strengthening, and gait training. After four weeks, patients can begin weight-bearing movement. The brace is worn for eight weeks or until the surgery site is healed and stable. X rays are performed at intervals of two weeks and eight weeks after surgery.
The usual general surgical risks of thrombosis and heart attack are possible in this open surgery. Osteotomy surgery itself involves some risk of infection or injury during the procedure. Combined surgery for ACL and osteotomy has higher morbidity rates.
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Feb. 17, 2009 The genome of a marine bacterium living 2,500 meters below the ocean's surface is providing clues to how life adapts in extreme thermal and chemical gradients, according to an article published Feb. 6 in the journal PLoS Genetics.
The research focused on the bacterium Nautilia profundicola, a microbe that survives near deep-sea hydrothermal vents. Microorganisms that thrive at these geysers on the sea floor must adapt to fluctuations in temperature and oxygen levels, ranging from the hot, sulfide- and heavy metal-laden plume at the vents' outlets to cold seawater in the surrounding region.
The study combined genome analysis with physiological and ecological observations to investigate the importance of one gene in N. profundicola. That gene, called rgy, allows the bacterium to manufacture a protein called reverse gyrase when it encounters extremely hot fluids from the Earth's interior.
Previous studies found the gene only in microorganisms growing in temperatures greater than 80°C, but N. profundicola thrives best at much lower temperatures.
"The gene's presence in N. profundicola suggests that it might play a role in the bacterium's ability to survive rapid and frequent temperature fluctuations in its environment," said Assistant Professor of Marine Biosciences Barbara Campbell, the study's lead scientist.
Additional University of Delaware contributors were Professor of Marine Biosciences Stephen Craig Cary, Assistant Professor of Marine Biosciences Thomas Hanson, and Julie Smith, marine biosciences doctoral student. Also collaborating on the project were researchers from the Davis and Riverside campuses of the University of California; the University of Louisville; the University of Waikato in Hamilton, New Zealand; and the J. Craig Venter Institute in Rockville, Md.
The researchers also uncovered further adaptations to the vent environment, including genes necessary for growth and sensing environmental conditions, and a new route for nitrate assimilation related to how other bacteria use ammonia as an energy source. Photosynthesis cannot occur in the hydrothermal vents' dark environment, where hot, toxic fluids oozing from below the seafloor combine with cold seawater at very high pressures.
These results help to explain how microbes survive near the vents, where conditions are thought to resemble those found on early Earth. Nautilia profundicola contains all the genes necessary for life in conditions widely believed to mimic those in our planet's early biosphere and could aid in understanding of how life evolved.
"It will be an important model system," Campbell said, "for understanding early microbial life on Earth."
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Aug. 5, 2009 Divers who held their breath for several minutes had elevated levels of a protein that can signal brain damage, according to a new study from the Journal of Applied Physiology. However, the appearance of the protein, S100B, was transient and leaves open the question of whether lengthy apnea (breath-holding) can damage the brain over the long term.
"The results indicate that prolonged, voluntary apnea affects the integrity of the central nervous system, and may have cumulative effects," the Swedish researchers said. The release of S100B into the blood suggests that holding one's breath for a long time disrupts the blood-brain barrier, they said.
The concern is that repetitive exposures to severe hypoxia (lowered oxygen supply), such as that experienced by individuals training and competing in static apnea diving events, could cause neurological damage over time. The researchers recommended further research on free divers that would begin early in their careers and follow them for years to monitor their neurological function.
The study is "Increased serum levels of the brain damage marker S100B after apnea in trained breath-hold divers: a study including respiratory and cardiovascular observations." The researchers are Johan P.A. Andersson, Mats H. Linér and Henrik Jönsson, of Lund University in Sweden. The American Physiological Society published the study.
Free diving is a tradition
There is a tradition of breath-hold diving in Japan and some other parts of the world that goes back hundreds of years, although the occupation has been dying out. These divers harvest seaweed, shellfish and other growth from the sea bottom, diving dozens of times per day. Some divers routinely dive to depths of 90 feet on a single breath while others dive in the 15-30 foot range.
More recently, breath-hold diving has become a competitive sport. Competitive events include how long divers can remain underwater, how far they can swim underwater and how deep they can dive. Participants must undergo intense training to increase their lung capacity while learning crucial safety measures.
Breath-hold diving often leads to hypoxia, elevated blood pressure, slowed heartbeat and other physiological changes. However, whether the sport causes any long-term damage to the brain has remained a point of contention. Studies have produced conflicting results.
The authors of this study see cause for concern, noting that in six international competitions between 1998 and 2004, 10% of the contestants in the static apnea events were disqualified after they lost either motor control or consciousness. In this event, participants float face down on the water for as long as possible without coming up for air. The world record for the event is 11 minutes 35 seconds. Divers at international competitions routinely hold their breath 4-7 minutes.
"Whether such hypoxic episodes are associated with a risk for brain damage in these athletes remains to be established," the researchers said. "Studying the changes in established biochemical markers of brain damage after such performances offers the possibility to address this question."
Breath hold experiment
Nine competitive breath-hold divers (eight men and one woman) took part in this study, along with six individuals who had limited experience with breath-hold diving. The nine competitive divers formed the experimental group, while the non-divers acted as the controls
The researchers told the participants to lie on their backs on a cot and hold their breath for as long as possible. The conditions were dry, but mimicked a static apnea dive in which the divers float face down holding their breath. The divers used whatever preparatory techniques they customarily use in competition, such as hyperventilating, insufflation (filling the lungs with as much air as possible) and breath-holding warm-ups.
The researchers took arterial blood samples from a catheter inserted into the artery that runs through the wrist. They took samples before the breath hold, at the end of the breath hold and at fixed intervals for the two hours following the end of the breath hold. The researchers also measured arterial blood gases. They did the same measurements on the individuals in the control group, but the controls rested on their backs for the entire experiment, without performing the breath hold or the warm-ups.
Among the findings of this experiment:
- The average breath-hold time was 5 minutes 35 seconds. The longest was 6 minutes 43 seconds and the shortest was 4 minutes 41 seconds.
- The marker for brain damage, S100B, rose in seven of the nine divers.
- The controls showed no change in S100B
- On average, S100B rose 37% within 10 minutes after the apnea ended.
- S100B levels returned to normal within two hours for all the participants.
- The divers showed signs of asphyxia, that is, blood oxygen levels fell, while carbon dioxide levels rose.
The S100B levels, while elevated, were well below levels associated with brain injury. In brain-injured patients, the presence of S100B in the blood can increase by several hundred percent.
In addition, the elevation of S100B was more transient in the divers, compared to people who suffered brain injury. The divers had a quick return to normal, while S100B levels peak in 24 hours in brain-injured patients.
The transient nature of the increase in S100B among the divers probably indicates the blood-brain barrier has been compromised, allowing the protein to escape from the fluid in the brain into the circulation. The blood-brain barrier controls what passes between the brain and the circulation. S100B would normally remain in the brain.
Other sports have also been associated with a similar transient increase in S100B, the researchers noted, including boxing, headings in soccer, running and long-distance swimming. One study also reported that individuals suffering sleep apnea had elevated levels of S100B in the morning, although another study indicated there had been no change in S100B overnight.
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- Johan P. A. Andersson, Mats H. Liner, and Henrik Jonsson. Increased serum levels of the brain damage marker S100B after apnea in trained breath-hold divers: a study including respiratory and cardiovascular observations. J Appl Physiol, Jul 2009 DOI: 10.1152/japplphysiol.91434.2008
Note: If no author is given, the source is cited instead.
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Jan. 30, 2011 In a new study, scientists at the University of Maryland and the Institut Pasteur show that bacteria evolve new abilities, such as antibiotic resistance, predominantly by acquiring genes from other bacteria.
The researchers new insights into the evolution of bacteria partly contradict the widely accepted theory that new biological functions in bacteria and other microbes arise primarily through the process of gene duplication within the same organism. Their just released study will be published in the open-access journal PLoS Genetics on January 27.
Microbes live and thrive in incredibly diverse and harsh conditions, from boiling or freezing water to the human immune system. This remarkable adaptability results from their ability to quickly modify their repertoire of protein functions by gaining, losing and modifying their genes. Microbes were known to modify genes to expand their repertoire of protein families in two ways: via duplication processes followed by slow functional specialization, in the same way as large multicellular organisms like us, and by acquiring different genes directly from other microbes. The latter process, known as horizontal gene transfer, is notoriously conspicuous in the spread of antibiotic resistance, turning some bacteria into drug-resistant 'superbugs' such as MRSA (methicillin-resistant Staphylococcus aureus), a serious public health concern.
The researchers examined a large database of microbial genomes, including some of the most virulent human pathogens, to discover whether duplication or horizontal gene transfer was the most common expansion method. Their study shows that gene family expansion can indeed follow both routes, but unlike in large multicellular organisms, it predominantly takes place by horizontal transfer.
First author Todd Treangen, a postdoctoral researcher in the University of Maryland Center for Bioinformatics and Computational Biology and co-author Eduardo P. C. Rocha of the Institut Pasteur conclude that because microbes invented the majority of life's biochemical diversity -- from respiration to photosynthesis --, "the study of the evolution of biology systems should explicitly account for the predominant role of horizontal gene transfer in the diversification of protein families."
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- Todd J. Treangen, Eduardo P. C. Rocha. Horizontal Transfer, Not Duplication, Drives the Expansion of Protein Families in Prokaryotes. PLoS Genetics, 2011; 7 (1): e1001284 DOI: 10.1371/journal.pgen.1001284
Note: If no author is given, the source is cited instead.
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Feb. 24, 2011 Why, and when, do we learn to speak the way that we do? Research from North Carolina State University on African-American children presents an unexpected finding: language use can go on a roller-coaster ride during childhood as kids adopt and abandon vernacular language patterns.
"We found that there is a 'roller-coaster effect,' featuring an ebb and flow in a child's use of vernacular English over the course of his or her language development," says Dr. Walt Wolfram, William C. Friday Distinguished University Professor of English Linguistics at NC State and co-author of several recent papers describing the research. "This was totally unanticipated." Vernacular English is defined here as culturally specific speech patterns that are distinct from standard English; in this case, the vernacular is African-American English (AAE).
One implication of the finding involves education, since teachers often advocate teaching standard English early in a childhood education. "This approach does seem to work at first," Wolfram says, "but it doesn't last." In other words, if a school system wants its students to graduate high school with a strong foundation in standard English, it may have to revisit standard English later in the education curriculum.
Specifically, the researchers found that children come to school speaking English with a relatively high number of vernacular features. Then, through the first four grades of elementary school, those features are reduced, as children adopt more standard English language patterns. As the children move toward middle school, the level of vernacular rises -- though many children often reduce their use of vernacular again as they enter high school.
"This finding reveals a cyclic pattern in the use of African-American vernacular English that no one expected to see during children's language development," says Janneke Van Hofwegen, a research associate at NC State and co-author of the study. "This wasn't even a hypothesis when we began the study."
The researchers note that, while their data looked solely at African-American children, the findings may be applicable more broadly to other groups.
The research stems from the longest, and largest, study ever to examine the longitudinal development of language in African-American children. The study began in 1990, following 88 African-American children from central North Carolina in order to track their language development. The study is ongoing, with 68 of the original participants still being tracked. The data is collected by the Frank Porter Graham Child Development Institute in Chapel Hill, N. C.
The retention rate of the participants is remarkably high, particularly given that approximately 71 percent of the children were living below the poverty line in 1990. "It's incredible, and gives us a rare opportunity to study language development in children," Wolfram says.
The study also gives researchers an impressive array of data, providing them with access to school and test data, as well as the data collected through the study's own interviews and surveys.
Researchers are currently assessing how and whether dialect use is related to literacy skills, as well as the role that mothers play in their children's use of vernacular.
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- Wolfram, Walt, Janneke Van Hofwegen, Mary Kohn, Jennifer Renn. Trajectories of Development in AAE: The First 17 Years. Proceedings of the Conference on African American Language in Popular Culture, (in press)
- Janneke Van Hofwegen, Walt Wolfram. Coming of age in African American English: A longitudinal study. Journal of Sociolinguistics, 2010; 14 (4): 427 DOI: 10.1111/j.1467-9841.2010.00452.x
Note: If no author is given, the source is cited instead.
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Nov. 8, 2012 A completely new way of delivering anti-cancer drugs to tumours, using "minicells" derived from bacteria, has been tested for the first time in humans and found to be safe, well-tolerated and even induced stable disease in patients with advanced, incurable cancers with no treatment options remaining.
The research, which is presented at the 24th EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics in Dublin, Ireland, November 9, suggests that it could be possible to use this new technology for targeted delivery of other drugs to a range of cancers, and to personalise treatment by adjusting the drugs to suit the genetic make-up of each patient's tumour .
Dr Himanshu Brahmbhatt and Dr Jennifer MacDiarmid, the founders of EnGeneIC, a biotech company in Sydney, Australia, designed the minicells to deliver anti-cancer drugs directly to tumour cells, thereby reducing the toxic side-effects that are seen when chemotherapy is given to patients systemically. The minicells are created from small bubbles of cell membrane pinched off the surface of mutant bacteria. The minicells can then be loaded with chemicals, such as anti-cancer drugs, and coated with antibodies that home in on receptors on the surface of tumour cells. This means that the minicells target the cancer cells, while avoiding normal cells that do not have the same receptors. The cancer cell recognises the bacteria from which the minicell has been derived and activates its standard defence by swallowing the minicell, which exposes the cell nucleus to whatever cancer-killing drug the minicell is carrying.
Each minicell is about 200 times smaller in diameter than a human hair (it measures 400 nanometres (nM) -- a nM being one billionth of a metre). "Nonetheless, this is much larger than synthetic particles in development for drug delivery," said Associate Professor Benjamin Solomon (MBBS, PhD, FRACP), the principal investigator of the trial and a consultant medical oncologist at the Peter MaCallum Cancer Centre in Melbourne, Australia. "This larger size means that the minicells preferentially fall out of the leaky blood vessels around the tumour and do not end up in the liver, gut and skin where they could cause nasty side-effects like smaller particles do."
Work in the laboratory and in animals had already shown that the minicells worked in the way they were designed to, but this trial is the first time that they have been used in humans.
Professor Solomon said: "In this study we loaded the cells with a cytotoxic chemotherapy drug called paclitaxel (which is currently used in many tumour types) and coated the minicells with an antibody targeting the loaded minicells to tumours expressing the Epidermal Growth Factor Receptor (EGFR) -- a protein that is found on the surface of many cancer cells. The study was then conducted in the way standard phase I studies are conducted to determine the safety and toxicity of minicells by treating small groups of patients with progressively higher doses of minicells and closely monitoring safety and toxicity."
A total of 28 patients with advanced, incurable cancers were treated with the minicells in four centres in Australia. Ten patients had stable disease at six weeks and received more than one cycle of minicells.
"The key finding of the study is that minicells can be given safely to patients with advanced cancer," said Prof Solomon. "Additionally, we showed that we could give multiple doses and one patient received 45 doses over 15 months. The major toxicity we observed was a mild self-limiting fever seen on the day of the infusion with little or no side-effects seen in the remainder of the following week. At higher doses we found that there were additional side-effects, in particular changes in liver function tests, which, although asymptomatic, prevented us from raising the doses of the treatment higher.
"This important study shows for the first time that these bacterially-derived minicells can be given safely to patients with cancer. It thereby allows further clinical exploration of a completely new paradigm of targeted drug delivery using this platform coupled with different 'payloads' of cell-killing drugs or other treatments such as RNA interference, and with different targeting antibodies."
He concluded: "The minicell technology is a platform for the targeted delivery of many different molecules, including drugs and molecules for silencing rogue genes which cause drug resistance in late stage cancer. The technology can also be viewed as a powerful antibody drug conjugate where up to a million molecules of drug can be attached to targeting antibodies and delivered to the body in a safe way. In the future this will enable a truly personalised medicine approach to cancer treatment, since the minicell payload can be adjusted depending on the genetic profile of the patient."
Phase II trials of the minicells are now being planned, including a trial in patients with glioblastoma (a type of brain tumour) using minicells loaded with doxorubicin. The researchers also want to develop imaging methods to track the minicells in patients.
Professor Stefan Sleijfer, the scientific chair of the EORTC-NCI-AACR Symposium, from Erasmus University Medical Centre (The Netherlands), commented: "Approaches resulting in selective delivery of anti-cancer drugs to tumour cells is highly interesting as it may lead to a reduction in adverse side-effects and improved anti-tumour activity. In this respect, the use of 'minicells' is a novel and promising technique."
EORTC [European Organisation for Research and Treatment of Cancer, NCI [National Cancer Institute], AACR [American Association for Cancer Research].
Abstract no: 585. Poster session, Phase I trials, 09.00 hrs, 9 November.
The study was funded by EnGeneIC. Prof Solomon has not received any remuneration from EnGenIC and declares no relevant conflicts of interest.
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American Labor Merit Badge Requirements
|1) Using resources available to you, learn about working people and work-related concerns. List and briefly describe or give examples of at least EIGHT concerns of American workers. These may include, but are not limited to, working conditions, work place safety, hours, wages, seniority, job security, equal-opportunity employment and discrimination, guest workers, automation and technologies that replace workers, unemployment, layoffs, outsourcing, and employee benefits such as health care, child care, profit sharing, and retired benefits.
2) With your counselor's and parent's approval and permission, visit the office or attend a meeting of a local union, a central labor council, or an employee organization, or contact one of these organizations via the internet. Then do EACH of the following:
A) Find out what the organization does.
B) Share the list of issues and concerns you made for requirement 1. Ask the people you communicate with which issues are of greatest interest or concern to them and why.
C) Draw a diagram showing how the organization is structured, from the local to the national level, if applicable.
3) Explain to your counselor what labor unions are, what they do, and what services they provide to members. In your discussion show that you understand the concepts of labor, management, collective bargaining, negotiation, union shops, open (nonunion) shops, grievance procedures, mediation, arbitration, work stoppages, strikes, and lockouts.
4) Explain what is meant by the adversarial motto of labor-management relations, compared with a cooperative-bargaining style.
5) Do ONE of the following:
A) Develop a time line of significant events in the history of the American labor movement from the 1770's to the present.
B) Prepare an exhibit, a scrapbook, or a computer presentation, such as a slide show, illustrating three major achievements of the American labor movement and how those achievements effect American workers.
C) With your counselor's and parent's approval and permission, watch a movie that addresses organized labor in the United States. Afterwards, discuss the movie with your counselor and explain what you learned.
D) Read a biography(with your counselor's approval) of someone who has made a contribution to the American labor movement. Explain what contribution this person has made to the American labor movement.
6) Explain the term "Globalization". Discuss with your counselor some effects of globalization on the work force in the United States. Explain how this global work force fits into the economic system of this country.
7) Choose a labor issue of widespread interest to American workers-an issue in the news currently or known to you from your work on this merit badge. Before your counselor, or in writing, argue both sides of the issue, first taking management's side, then presenting labor's or the employees point of view. In your presentation, summarize the basic rights and responsibilities of employers and employees, including union members and nonunion members.
8) Discuss with your counselor the different goals that may motivate the owners of a business, it's stockholders, it's customers, it's employees, the employees' representatives, the community, and public officials. Explain why agreements and compromises are made and how they effect each group in achieving it's goals.
9) Learn about opportunities in the field of labor relations. choose one career in which you are interested and discuss with your counselor the major responsibilities of that position and the qualifications, education, and training such a position requires.
Source: Boy Scout Requirements, 33215, revised 2007
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"Mobile computing" describes the use of computing technology on the go, through devices such as smartphones, tablets, portable computers, and wearable computers and sensors. The SEI is focusing on pervasive mobile computing at the tactical edge—environments in which front-line soldiers and first responders operate.
The SEI is working to realize this vision for soldiers and first responders:
- Front-line soldiers: Dismounted soldiers receive information that is more relevant and useful for their current mission, on devices that consume fewer battery and bandwidth resources, using applications that they can readily customize to support their needs.
- Humanitarian assistance/disaster response: On-scene responders with access to local information about resource needs of victims—such as food, water, shelter, and medicine—can make better decisions that maximize use of local resources and external assistance.
The SEI explores the architecture and implementation of mobile systems that increase the flexibility of edge users to respond to diverse missions. In these systems, "pervasive computing"—the use of devices embedded with chips that can connect to a network—plays a major role.
Learn about our research in pervasive mobile computing.
Download our information sheet about the Advanced Mobile Systems Initiative.
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[ View the story "Climate change: What can Obama do without Congress?" on Storify]
Climate change: What can Obama do without Congress?
With the House controlled by Republicans, some environmentalists are urging President Obama to take action on climate change on his own. Here are five things he could do.
Digital First Media· Mon, Feb 11 2013 06:02:45
President Barack Obama has pledged to make addressing climate change a major priority in his second term. But House Republicans remain skeptical about both the problem and potential legislative solutions.
That’s led many environmentalists to urge Obama to go it alone and take actions to reduce America’s greenhouse gas emissions on his own. Below are five major things he could do without congressional approval.
Use the EPA’s authority
In 2007, the Supreme Court
that the Environmental Protection Agency has the authority to regulate greenhouse gas emissions such as carbon dioxide under existing air pollution laws. The ruling empowered the agency to set higher standards for new power plants and write
new regulations for older power plants
Some environmentalists think Obama should take advantage of the EPA’s newfound powers to restrict emissions as much as possible. That would still fall short of what a comprehensive bill passed through Congress could do, however, and it might spark a backlash from big business.
Reduce methane emissions
Considered the second most significant greenhouse gas, methane is released from leaks in gas pipelines and coal mines, from landfills and livestock and agriculture. Some scientists think reducing methane in the atmosphere could
delay the effects of climate change
by as much as 15 years.
Obama could order the EPA, the Department of Energy and other federal agencies to refocus efforts at reducing methane emissions by capturing methane released at coal mines, reducing methane from landfills or even requiring more frequent draining of rice paddies.
Soot, also known as black carbon, is another concern for environmentalists.
One recent study
argued that black carbon is a more dangerous greenhouse gas than methane because its color causes it to take in more solar radiation.
Obama could order federal agencies crack down on
such as diesel engines, coal-fired power stations and coal-burning cookstoves. However, coal is already cleaner in the U.S. than it used to be, so there may be a limit on how much this can be addressed within the United States alone.
Approve more renewable energy
Obama can order
to focus on climate change including the Department of Energy, that State Department and the Department of the Interior.
Between Interior and the Department of Agriculture, the
government manages 700 million acres
of land, with another 1.7 billion acres of offshore continental shelf managed by the Interior Department alone. Public lands are prime real estate when it comes to energy development, from coal mining to wind farms.
The administration could approve more renewable energy projects on federal lands. Though that would not subtract any greenhouse gas emissions from existing sources, it would reduce how many are added to the air in the future.
Reject the Keystone XL pipeline
Many environmentalists argue that the Obama administration needs to
reject the proposed Keystone XL pipeline
because it would promote the use of fossil fuels and create emissions from the extraction process. Still, there is uncertainty about how much the pipeline itself actually would
increase oil sands production
and how the oil it produces might end up being used.
Obama rejected the Keystone XL pipeline last year while in the midst of a re-election campaign, but the project is still alive. A number of senators have urged Obama to allow the pipeline, arguing they want to see energy resources developed in this country, but Obama will have a lot of power to block the pipeline if he wants.
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Can We Teach Computers What “Truth” Means?
It’s harder than it sounds.
Courtesy of null0/Flickr
This article arises from Future Tense, a partnership of Slate, the New America Foundation, and Arizona State University. From Feb. 28 through March 2, Future Tense will be taking part in Emerge, an annual conference on ASU’s Tempe campus about what the future holds for humans. This year’s theme: the future of truth. Visit the Emerge website to learn more and to get your ticket.
I’d like to begin with two different ideas of truth. The first appears to be the simplest: “It is true that 1+1=2.” The second is from the beginning of the Declaration of Independence: “We hold these truths to be self evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty, and the pursuit of Happiness.” Now, these sound like quite different ideas about truth. But the process of trying to teach computers to understand truths like these—difficult for both notions—is revealing the ways in which they are similar.
The term artificial intelligence was coined in 1955 by a computer scientist named John McCarthy. Early on, McCarthy enunciated his key aim as the systematization of common sense knowledge. In 1959, he wrote: “[A] program has common sense if it automatically deduces for itself a sufficiently wide class of immediate consequences of anything it is told and what it already knows.” This has proven very difficult, primarily because it is difficult to encode, in a systematic fashion, what it means to say something is true.
Even “1+1=2” is less obvious than it seems at first. Beginning in the early part of the 20th century, mathematicians and philosophers, led at first by Bertrand Russell and Gottlob Frege and later by Ludwig Wittgenstein, Kurt Gödel, Alan Turing, and others, tried to see whether mathematical knowledge—facts like “1+1=2”—could be reduced to the laws of logic. (By logic, Frege meant “those laws of thought that transcend all particulars.” The most basic principle of logic is perhaps the conviction that nothing exists—it is possible to name a set that has no elements.) David Hilbert, the dean of mathematics at the dawn of the century, had thought that such a reduction was possible and posed it as a challenge.
But Hilbert was doomed to failure here. The reason for this, at a basic level, is self-reference. Sentences like “This sentence is false” turn out to pose a nasty set of technical challenges that make it impossible to fully express mathematical knowledge as a consequence of logical axioms—things that are held, on their face, to be true.
Gödel, an Austrian logician who would become a good friend of Albert Einstein’s after both of them settled in Princeton, proved this in a 1931 paper, whose consequences were later strengthened by Turing. Gödel’s incompleteness theorem says that in any sufficiently strong logical system (meaning one that is rich enough to express mathematics), it is impossible to prove that the axioms—the assumptions—of the system do not lead to a contradiction.
The importance of Gödel’s incompleteness theorems for artificial intelligence is something that remains hotly debated. One school of thought, as Ernest Nagel and James Newman wrote in 1956, holds that incompleteness means “that the resources of the human intellect have not been, and cannot be, fully formalized, and that new principles of demonstration forever await invention and discovery.” The other school of thought says, basically, “Don’t worry about it!” The best-known recent exponent of this school is Ray Kurzweil, who claims, without much evidence, that “there is an essential equivalence between a computer and the brain.”
Kurzweil’s overheated triumphalism aside (he seems determined to prove that careful thought is not necessary to be human by displaying a tremendous lack of care himself), this is not a question that we need to resolve to say something about what current progress in artificial intelligence is doing to the idea of truth. Even if Nagel and Newman are right and human intellect cannot be fully formalized, computer scientists have come a long way since John McCarthy first enunciated the aim of formalizing common sense.
Computer scientists have worked to come up with formal descriptions of the everyday world. Here is a short list, taken from the Stanford Encyclopedia of Philosophy of some of scenarios they’ve tried to encode:
The Baby Scenario, the Bus Ride Scenario, the Chess Board Scenario, the Ferryboat Connection Scenario, the Furniture Assembly Scenario, the Hiding Turkey Scenario, the Kitchen Sink Scenario, the Russian Turkey Scenario, the Stanford Murder Mystery, the Stockholm Delivery Scenario, the Stolen Car Scenario, the Stuffy Room Scenario, the Ticketed Car Scenario, the Walking Turkey Scenario, and the Yale Shooting Anomaly.
Let’s take the last of these—the Yale Shooting Anomaly, which aims to formally codify the fact that an unloaded shotgun, if loaded and then shot at a person, would kill the person. Classical logic dealt with things like “1+1=2” which are true, (or false, like 1=0) for all time. They were true, are true, and always will be true. It doesn’t allow for things to happen. But to encode common- sense knowledge, computer scientists need a way to allow for events to take place. They also need ways to encode spatial locations.
Some of this had been worked out in a rigorous but limited way, in what philosophers call modal logic, which was first enunciated by C.I. Lewis in 1918. But modal logic was too limited for computer scientists to use in semireal world systems. In the languages that computer scientists have come up with, as in the Yale Shooting Anomaly, they were unable to preclude the possibility that the shotgun would spontaneously unload itself. It’s not that computer scientists think that that will happen; it’s that they struggle to formalize how it can’t. (Since the Yale Shooting Anomaly was first stated in 1986, many solutions have been proposed, but it remains an area of research.)
A central challenge computer scientists face is what’s called the ramification problem: How to codify that fact that if I walk into a room, my shirt does, too. This is paralleled by the “frame problem,” first enunciated by McCarthy in 1969, which is the “problem of efficiently determining which things remain the same in a changing world.” These problems are considerably harder than careless cheerleaders like Kurzweil make them out to be.
The central result of logicians in the 20th century was that, in the end, it will always be necessary to extend your axioms—things you just assume to be true without proving them—if you are to extend your idea of truth. This brings us to our second idea about truth—that men are created equal and entitled to life, liberty, and the pursuit of happiness. Thomas Jefferson’s insight (without getting into the abominable hypocrisy of the fact that slavery was legal at the time) was that these truths were not provable from some more basic system of logic, but must themselves be assumed.
The sense in which artificial intelligence research has eroded the distinction between such moral truths and mathematical truths is not a rigorous philosophical identification of the two, but just a sense that truths of the first sort are not as absolute as they seem (at the end the fights between logicians come down to opinion and taste) while truths of the second sort can be, grudgingly and with struggle, written down in a form that outwardly resembles the simpler-seeming truths of mathematics.
Konstantin Kakaes is a Schwartz fellow at the New America Foundation. Follow him on Twitter.
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Will the US Face Blackouts as Electricity Generation Suffers in Drought?
Well, its official – the U.S. government has acknowledged that the U.S. is in the worst drought in over 50 years, since December 1956, when about 58 percent of the contiguous U.S. was in moderate to extreme drought.
According to the National Oceanic and Atmospheric Administration National Climatic Data Center’s “State of the Climate Drought July 2012″ report, “Based on the Palmer Drought Index, severe to extreme drought affected about 38 percent of the contiguous United States as of the end of July 2012, an increase of about 5 percent from last month… About 57 percent of the contiguous U.S. fell in the moderate to extreme drought categories (based on the Palmer Drought Index) at the end of July… According to the weekly U.S. Drought Monitor, about 63 percent of the contiguous U.S. (about 53 percent of the U.S. including Alaska, Hawaii, and Puerto Rico) was classified as experiencing moderate to exceptional (D1-D4) drought at the end of July.”
Much business writing on the effects of the drought have focused on its agricultural aspects. To give but one, the hottest, driest summer since 1936 scorching the Midwest have diminished projected corn and soybean crop yields s in the U.S. for a third straight year to their lowest levels in nine years. Accordingly, the price of a bushel of corn has jumped 62 percent since 15 June and soybeans gained 32 percent in the same period.
But as consumers fret about the inevitable rise in food prices to come, the drought is unveiling another, darker threat to the American lifestyle, as it is now threatening U.S. electricity supplies.
Because virtually all power plants, whether they are nuclear, coal, or natural gas-fired, are completely dependent on water for cooling. Hydroelectric plants require continuous water flow to operate their turbines. Given the drought, many facilities are overheating and utilities are shutting them down or running their plants at lower capacity. Few Americans know (or up to this point have cared) that the country’s power plants account for about half of all the water used in the United States. For every gallon of residential water used in the average U.S. household, five times more is used to provide that home with electricity via hydropower turbines and fossil fuel power plants, roughly 40,000 gallons each month.
Michael Webber, associate director of the Center for International Energy and Environmental Policy at the University of Texas at Austin, is under no such illusions, stating that the summer’s record high heat and drought have worked together to overtax the nation’s electrical grid, adding that families use more water to power their homes than they use from their tap. Webber said, “In summer you often get a double whammy. People want their air-conditioning and drought gets worse. You have more demand for electricity and less water available to produce it. That is what we are seeing in the Midwest right now, power plants on the edge.”
In July U.S. nuclear-power production hit its lowest seasonal levels in nine years as drought and heat forced Nuclear power plants from Ohio to Vermont to slow output. Nuclear Regulatory Commission spokesman David McIntyre explained, “Heat is the main issue, because if the river is getting warmer the water going into the plant is warmer and makes it harder to cool. If the water gets too warm, you have to dial back production,” McIntyre said. “That’s for reactor safety, and also to regulate the temperature of discharge water, which affects aquatic life.”
Nuclear is the thirstiest power source. According to the National Energy Technology Laboratory (NETL) in Morgantown, West Virginia, the average NPP that generates 12.2 million megawatt hours of electricity requires far more water to cool its turbines than other power plants. NPPs need 2725 liters of water per megawatt hour for cooling. Coal or natural gas plants need, on average, only 1890 and 719 liters respectively to produce the same amount of energy.
And oh, the National Weather Service Climate Prediction Center in its 16 August “U.S. Seasonal Drought Outlook” wrote, “The Drought Outlook valid through the end of November 2012 indicates drought conditions will remain essentially unchanged in large sections of the central Mississippi Valley, the central and southwestern Great Plains, most of the High Plains, the central Rockies, the Great Basin, and parts of the Far West…” The lack of rain and the incessant heat, has also increased the need for irrigation water for farming, meaning increasing competition between the agricultural and power generation sectors for the same shrinking water “pool.”
But, every cloud has a silver lining. California’s Pacific Gas and Electric Co. utility, commonly known as PG&E, that provides natural gas and electricity to most of the northern two-thirds of California, from Bakersfield almost to the Oregon border, is on the case. PG&E has informed its customers that its “Diablo Canyon (nuclear) Power Plant, the largest source of generation in the utility’s service area, is cooled by ocean water, not by rivers that could dry up.”
Never mind the fact that by the time the Diablo Canyon NPP was completed in 1973, engineers discovered that it was several miles away from the Hosgri seismic fault, which had a 7.1 magnitude earthquake on 4 November 1927.
But ocean water as a coolant is not necessarily the answer either.
On 12 August Dominion Resources’ Millstone NPP, situated on Connecticut’s Niantic Bay on Long Island Sound, was forced to shut down one of two reactor units because seawater used to cool down the plant was too warm, averaging 1.7 degrees above the NRC limit of 75 degrees Fahrenheit. The Millstone NPP, which provides half of all power used in Connecticut and 12 percent in New England, was only restarted twelve days later.
The federal government is hardly known for its scaremongering tactics, but it would seem that Mother Nature is forcing Americans to belatedly consider making some lifestyle changes, as the choice seems to be devolving into energy conservation, turning down the air conditioner and digging deeper into the wallet for food costs.
It might also be time for serious national discussion about renewable energy, including wind and solar.
If the sun stops shining, all bets are off.
By. John C.K. Daly of Oilprice.comhome solar power, hydroelectric plants, national oceanic and atmospheric administration, palmer drought index
Short URL: http://www.solarthermalmagazine.com/?p=21120
| 3.038806 |
CubeSat Thruster: Engine of Creation
A worry about the proliferation of CubeSat satellite launches is adding clutter to an already troublesome amount of Earth-circling debris.
If CubeSats were deployed at higher orbits, they would take much longer to degrade, potentially creating space clutter. As more CubeSats are launched farther from Earth in the future, the resulting debris could become a costly problem.
“These satellites could stay in space forever as trash,” says Paulo Lozano, an associate professor of aeronautics and astronautics at the Massachusetts Institute of Technology (MIT). This trash could collide with other satellites. “You could basically stop the Space Age with just a handful of collisions,” he suggests.
Today, more than two dozen CubeSats orbit Earth – each slightly bigger than a Rubik’s cube, and tip the scale at less than three pounds.
But now, an ultra-small rocket thruster could soon power the smallest of satellites in space. As small as a penny, these thrusters run on jets of ion beams.
The device, fabricated by Lozano, is a flat, compact square — much like a computer chip — covered with 500 microscopic tips that, when stimulated with voltage, emit tiny beams of ions. Together, the array of spiky tips creates a small puff of charged particles that can help propel a shoebox-sized satellite forward.
Lozano and his colleagues found that an array of 500 tips produces 50 micronewtons of force — an amount of thrust that, on Earth, could only support a small shred of paper. But in zero-gravity space, this tiny force would be enough to propel a two-pound satellite.
This new technology could enable CubeSats to propel down to lower orbits to burn up, or even act as space garbage collectors, pulling retired satellites down to degrade in Earth’s atmosphere.
The MIT researchers envision a small satellite with several microthrusters, possibly oriented in different directions. When the satellite needs to propel out of orbit, onboard solar panels would temporarily activate the thrusters.
In the future, Lozano predicts, microthrusters may even be used to power much larger satellites: Flat panels lined with multiple thrusters could propel a satellite through space, switching directions much like a rudder, or the tail of a fish.
“Just like solar panels you can aim at the sun, you can point the thrusters in any direction you want, and then thrust,” Lozano says. “That gives you a lot of flexibility.”
For a video clip on this work, go to:
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The painting machine was a light-sensitive spray-gun.
When light fell on the light cell the spray-gun would stop spraying.
It only sprayed when there was no light.
The light cell was situated at the end of a tube, so it would only react to the light directly hitting straight into the length of the tube.
If it encountered a dark point, the spray-would spray; if not, it would shut.
The spray was hoisted onto a wooden construction which moved back and forth along the wall.
It reacted to the dark and light points in the room and painted them on the wall.
It creates a photographic image, in which all perspective is vanished.
All the objects in the image are the same size as the real objects.
| 3.226967 |
of the Bible
||A Timeline is an easy way to visualize the timing and order of the
stories and major events in the Bible. You can also use a Timeline
to emphasize that the events recorded in the Bible are true and really
||Use a Bible Drill to reinforce a topic from a story.
|Creation Clothes Pins
||Use this matching game to remind the
preschoolers of all that God created.
||Preschoolers will love coloring with these Creation
Crayons that you can make.
||Write a story and use the black and white Coloring
Pages to illustrate the book.
Tape butcher paper on wall.
Children use markers, colors,
magazine pictures, stickers, etc. to create a picture that tells a story
or illustrates a Bible Truth. The
||Jesus Called the Apostles,
Sermon on the Level Place, The
Good Samaritan, Jesus
Taught About Prayer, Recreate the Last
|Ask the Whiz Kid - Part I
||The children learn about sin, forgiveness, and demonstrating faith by
responding to real life situations.
|What is Sin and
||What is sin and how does it affect a person's relationship with
God? What is forgiveness?
||What is more important - to have your sins forgiven or to have your body
|Ask the Whiz Kid
- Part II
||The children think about who Jesus is by responding to real life
|Building Blocks 101
||Use this demonstration to help the children
understand the strength of a church or a life which has Jesus Christ as
|Signs of Success
||Children rank the success of six adults to learn that the value of a person should be based on an eternal life with God and
not material assets.
|Get Well Card
||Let the children choose markers, colors, pens, construction paper,
etc. to use in designing a Get Well Card for a friend.
||Set up a doctor station and let the younger students play with Ace
bandages, play stethoscopes, crutches, or whatever you have.
|The Healing Power of
||Discuss childhood ailments and their cures to teach about faith,
trust, and Jesus' power over sickness.
Place 2" masking tape on the child's wrist, sticky side out.
Take a nature walk and let the children create their nature
bracelets by sticking grass, pebbles, leaves, flowers, etc. to the bracelet.
Collect leaves, large blades of grass, flat rocks, small
sticks, etc. Select a leaf, blade of grass or whatever and lay it flat on
the table. Cover it with white paper and rub the top of the paper with
|Nature Scavenger Hunt
Divide the children into several groups. Give each group a sack and a list of nature items to
collect. The list could include a rock, green leaf, brown leaf, flower, etc.
|Measure and Weigh the Class.
||Record the height and weight of each child on a Giraffe Measuring Chart.
||Take the kids outside and pick up litter on the church grounds.
Call From Jesus
||See if the children can identify whose behavior indicates they have
responded to the call from Jesus.
||Make a fishing pole and let the children catch paper fish.
||Use this activity to help the children understand what a Tax Collector
did and why Tax Collectors were disliked.
|Time for Prayer
||Encourage the children to follow the example of Jesus and pray before
making big decisions or doing something important. Let each child
tell about the activities planned for the coming week.
|What Do I Do?
||These situations help the children understand what Jesus meant when He
said to love your enemies.
||Learn the importance of following the right people.
|What is God Like?
||Use this activity to help the children understand the qualities of
|Put on the Armor of
||Younger students can learn the nature of Jesus and why He can be
|Put God's Armor to Work
||The children can actively demonstrate why a person can trust Jesus
when facing a difficult situation.
|Put Your Fears in a Box
||Trusting in Jesus can help when you are afraid.
|Read the story from a scroll
||Use butcher paper and dowels to make a scroll. Use the Bible
to copy the story on the scroll. Let the children take turns
reading the story from the scroll.
|Make a scroll
||Each student can
make a scroll using straws and letter size paper. The children
can write the Memory Verse or Bible Truth on the scroll.
|Don't Judge a Snack by
||Choices should not be based solely on appearances.
|The Suffering and Humiliation of
||Use visual aids to teach that Jesus suffered real pain and
is Responsible for the Death of Jesus?
||Discover that all sinners are responsible for the
death of Jesus.
and its Consequences
||Jesus died to give us eternal life because even the smallest sins make
us unacceptable to God.
||Children can agree to bear each other's punishment
for a week at a time.
|The Resurrection Egg Hunt
|| Use this
activity to reinforce the fact that Jesus rose from the dead.
|Go To Work For God
||Children learn the different kinds of things
they can do to help God bring people into His kingdom.
|Top 5 Countdown in Prayer
||Use this game to help the children understand there are no limits to
prayer. A person can pray whenever, wherever, and for whatever
there is a reason to pray.
Use this activity to help the children understand that they should love
others regardless of where they live, what they do, the language they speak,
|Search for the
||Use these activities to help the children
understand the joy God has when a person separated from God returns to
|| Use this activity to help
the children understand what they should do when a person turns from
God. The children can also think about how God acts towards a
sinner who asks for forgiveness and wants to return to God.
|The World vs. the Kingdom of God
||Use this activity to help the children understand how the requirements
for entry into God's kingdom differ from the standards sometimes imposed
by the world.
||Use this activity to help the children understand that Jesus fulfilled the
prophecies of the Old Testament prophets.
|Smell the Nard.
||Bring a sample of nard (also called spikenard or
Nardostachys jatamansi) and let the children smell the perfume
Mary used to anoint Jesus.
||What is temptation and how can it be resisted?
|The Definition of Sin
||Identify which sins make a person unacceptable to God.
|The Impact of
||Learn that sin affects more than just the sinner.
If Nobody's Watching
||Use this activity to help the children understand that God always
knows what is on our minds and in our hearts.
||Use this activity to help the children understand
that the more a person lives a sinful life, the easier it is to sin, and
the more a person tries to please God, the easier it gets to please God.
||Cain was a farmer. Abel was a
shepherd. Teach the children about other jobs
mentioned in the Bible by having a career day.
|Draw the Ark.
||Ask the children to read
Genesis 6:14-16 and use markers, colors and their imagination to draw
the ark Noah built.
||Use a US Jefferson 5¢ coin, a US Kennedy 50¢
coin, a US Sacagawea golden dollar, a container of coffee and a
child to teach the children about the units of weight used during
biblical times such as the shekel or the talent.
Child's Weight in Talents
||Do the children in your class
know how many talents they weigh? Use a scale and this conversion
chart to discover their weight in talents, minas, shekels, pims, bekas,
|Bible Story Activities - Weights
||Activities to help children visualize weights mentioned in the
Bible. Includes the weight of Rebekah's ring and bracelets,
David's crown, Goliath's armor and spear, the gold and silver David set
aside for the building of the temple and others.
||The children experience what it is like to be
the only person resisting temptation.
|Ask the Whiz Kid - Part III
||The children learn about favoritism and jealousy by
responding to real life situations.
||Help the children
understand that God can use any person to do His work, regardless of that
|Ways to Serve
the children think about different ways they can serve God.
||These Greek words are taken from James 1:22 and mean
"doers of the word". Teach the children to say these
words and encourage them to use the words as a special greeting for
anyone they meet. Since no one will understand what they are
saying, the children will then have to explain
that the words mean a person must do what the Bible says.
|Don't Play Favorites
||This activity will help the children learn through experience that
playing favorites is not the thing God wants us to do.
||God placed a rainbow in the
sky as a reminder of the covenant He made with Noah. Ask the
children to make up signs which can remind them of some of God's other
|The Promise Maker
||A person's promises reflect his or her character. Help the children
learn about God and His character by studying some of the promises He
has made to us.
||Use these questions in a game to review the
stories you have studied.
| 3.083376 |
For parents and teachers, bullying can be a worrying, complicated issue to resolve. Child bullying has been known to lead to injury and even death. For many people, one of the biggest questions about child bullying is why it happens in the first place. So why do kids bully one another, and how can you stop it?
Social problems. Many kids can turn to bullying as a way to solve other problems they are having. For children, it is normally easier to bully somebody than it is to work a problem out. At a young age, children are less likely to be able to manage their emotions or to learn how to solve problems the right way. Bullying often becomes a much easier way out, and is not necessarily a conscious decision.
Following an example. Bullying often occurs when a youngster is being bullied by others already or when behavior at home sets an example. Children who live with an abusive parent, for example, may not know any other means of getting their way than being aggressive and demonstrating bullying behaviors. If this is all that a child sees, he or she is unlikely to behave differently.
Gang mentality. Older children may become bullies because of peer pressure. Peer groups attack other kids verbally and emotionally, often because they are confused or uncertain of their own identities, and they feel the need to establish authority. Gang mentality occurs because other children see this behavior and decide that if they do not want to become victims of this themselves, they need to join the bullies.
How to respond. Bullying is a complex problem and needs to be carefully managed by parents. It is worth bearing in mind that bullying seldom occurs as a one-time event, so parents cannot expect resolution to be reached with a single action. Maintaining an open dialogue with your kids is critical, in terms of identifying if your child is being bullied or if your child is a bully. Setting the right example at home, in terms of conduct, is critical. Remember that the smallest of things can be taken by a child as permission to behave in this way.
What to do if your child is bullied. If you believe your child is being bullied, you must take action. Try to address the issue through proper channels. Talk to the school and give the personnel the opportunity to address the problem. In very severe cases, you may consider involving the police, but try to do so with the school's support. Remember that the parents of the bully may well be unreceptive to any contact that you have with them, so think carefully about approaching them or speaking to them in person.
| 3.627674 |
Source: Garland Science/Taylor and Francis Books, Inc.
In this animation adapted from Garland Science Publishing, a detailed look at DNA reveals the structural features that make up the famed double-helix molecule. The animation shows how the ladder-shaped DNA is constructed from chemical building blocks, including phosphates, sugars, and bases, held together by different kinds of chemical bonds. The narration further explains how the overall structure determines the charge and stability of the molecule, and how structure predicts key cellular functions of replication and transcription.
Every living thing contains building and operating instructions from a molecule inside all cells called deoxyribonucleic acid (DNA). DNA contains regions called genes that tell the cells which proteins to produce. At all levels of organization in the living world, structure and function are related. Thanks to the work of many researchers using different technologies, scientists now understand the structure and function of DNA at the molecular level.
DNA is a double-stranded molecule made up of two helical chains of nucleotides. This structure enables several important functions related to heredity and evolution. To enable these functions, the structure allows certain kinds of proteins, called regulatory proteins, to bind to and interact directly with the DNA. These regulatory proteins help to dictate replication and transcription (information encoding) by relaxing the DNA structure in the region where they are bound. The double-helix structure of DNA contains a major (wider) groove and a minor (narrower) groove. Because the nucleotide sequence is more accessible in the major groove, many proteins that bind to and interact with DNA do so here.
Through the process of DNA replication, genetic information is passed from parent cell to daughter cell whenever the parent cell divides. Complementary base pairing ensures that DNA strands are copied quickly and accurately. The DNA double-helix molecule is unzipped by the enzyme helicase, resulting in two strands that will act as templates for new DNA strands. These strands are referred to as antiparallel; they are oriented side by side, but their respective nucleotide sequences read in opposite directions. A DNA polymerase enzyme controls the replication of each strand, which occurs as free-floating nucleotides move in one by one to match up with the nucleotides present on each “old” strand of the unzipped ladder. This creates two identical DNA molecules, each made of an “old” strand and a “new” complementary strand.
The arrangement of bases in a DNA molecule determines the genetic code. Approximately once every 100,000,000 bases or so, this copying process makes errors, so that the wrong nucleotide is placed in position. These errors are called mutations. The cell corrects many of the mutations itself. When specialized repair proteins identify a mismatched base pair, they remove the incorrect nucleotide and give DNA polymerase a chance to correct the sequence.
To manufacture the proteins it needs, the cell must transcribe or copy the instructions contained in its DNA into RNA (ribonucleic acid). It uses the sequence of nucleotides in a given gene to produce a single-stranded complementary messenger RNA (mRNA). The mRNA is then translated by structures called ribosomes from the language of nucleotides into the amino acid sequence of proteins. Each amino acid is specified by a combination of three of the chemical bases (A, T, C, or G), called codons. The codons determine the sequence of the amino acids that are put together in a long chain to form the protein that the cell uses to perform specific jobs for the body.
Academic standards correlations on Teachers' Domain use the Achievement Standards Network (ASN) database of state and national standards, provided to NSDL projects courtesy of JES & Co.
We assign reference terms to each statement within a standards document and to each media resource, and correlations are based upon matches of these terms for a given grade band. If a particular standards document of interest to you is not displayed yet, it most likely has not yet been processed by ASN or by Teachers' Domain. We will be adding social studies and arts correlations over the coming year, and also will be increasing the specificity of alignment.
| 4.419858 |
Do you love you some mammals, reptiles, birds, amphibians,
fish or insects? Then check out these ideas for some inspiration
for your next project:
If you are concerned about endangered animals
- Identify a local animal species that is threatened or
endangered and research the causes of its decline.
- Gather data on when and where it’s found by observing it in
- Confer with local experts on the viability of a plan to protect
or increase its population (ex. develop a plan to protect or
restore part of its habitat).
If you like feeding animals
- Identify and research local species of butterflies and/or
- Design and plant a garden of their favorite food sources.
- Monitor the garden to collect data on which species the garden
attracts and to which plants they are attracted.
- Develop a guide or poster with planting and feeding information
for local property owners.
If you think bats get a bad rap
- Use donated and/or recycled materials to construct bat houses
and mount them in an appropriate area.
- Work to dispel myths about bats and teach people about their
significant ecological value (bats feed upon insects such as
mosquitoes, pollinate certain plants, and disperse seeds).
If you've got birds on the brain
- Research birds living in cities (ex. birds of prey found on
roofs of buildings) or suburban or rural areas (ex. songbirds in
- Use donated and/or recycled materials to create nest boxes for
- Get permission to hang the nest boxes in a park or on school
- Set up a monitoring station to observe the boxes and gather
- Present your findings to your community or a local
If reptiles are your thing
- Study the impact of high curbs on inhibiting movement of
- Work to have sloped areas added to all new curb
If you're always on the move
- Observe and document the migration patterns of a few different
- Create a migration map detailing the route individuals travel
through your town to share with local authorities, your school
district, environmental organizations, etc.
If you think fish are deelish
- Gather information about the kinds and the numbers of fish in a
local water source.
- Research the quality of those fish that are sold
- Distribute information on how to more safely eat fish from the
If you like running around with a net
- Collect and count the kinds and numbers of insects captured
(and released!) in an area over several months.
- Research the plants they pollinate, the animals that prey upon
them, how they defend themselves, etc.
- Monitor and track any change in populations over time.
Want to check out some more?
Check out our Water Project
Projects or Projects in
| 3.733465 |
May 18, 1833 – June 19, 1887
A dedicated and respected member of the Republican Party, Sampson W. Keeble was elected to represent Davidson County in the 38th Tennessee General Assembly
, 1873-1874. He was the first black Tennessean to serve in the state legislature. A Tennessee Historical Commission marker in downtown Nashville, near a one-time Keeble family home on South Broadway, proclaims,
Sampson W. Keeble, barber, businessman, and civic leader, became the
first African-American to serve in the Tennessee General Assembly.
Serving from 1873 to 1875, Keeble was appointed to the House Military
Affairs Committee and the Immigration Committee. After service in the legislature, he was elected magistrate in Davidson County, and served
from 1877 to 1882.
Early years in slavery
According to the date on his tombstone in Nashville’s Greenwood Cemetery, Keeble was born in 1833 in Rutherford County, Tennessee, to Sampson W. and Nancy (or Mary) Keeble. Their slave-owner’s father, Walter “Blackhead” Keeble, had stipulated in his 1816 will that his slaves were to be cared for, educated, and freed as soon as the law would allow, and that any of his heirs who did not agree to those requisites would inherit nothing – land, slaves, nor money. When Walter died, the inventory for his 1844 will listed among his slaves 11-year-old Sampson and 16-year-old Marshall (perhaps the father or grandfather of evangelist Marshall Keeble, 1878-1968). The two youngsters were inherited by Walter’s son, Horace Pinkney Keeble, a Rutherford County attorney. (At least one period newspaper named Horace’s brother Edwin A. Keeble as Sampson Keeble’s owner, but there is substantial evidence that Sampson was, in fact, part of H. P.’s household.) Also listed among Walter Keeble’s slaves, who were grouped by family, were Sampson’s mother, called Nancy Polly (40) to distinguish her from another woman named Nancy Betty (39); Sampson’s sisters Elisa Jane, 9 [the “Eliza A.” on Nancy’s tombstone], and Catherine, 2 [“Kitty”]; and brother George Lent, 6 [“Ceorce L”]; the tombstone appears to name one more child, with a name ending in “y.” That could be Joicy (six months old at the time of the inventory) or Billy Buck (age not given), both of whose names are listed near those of the Keeble family on the inventory sheet. There is no evidence that Pastor Marshall Keeble was related to this family, other than to share their slave owner’s surname.
The white Keebles always used the word “servant” instead of “slave” when referring to their workers (a common practice of Middle Tennessee slave owners), and they seem to have treated their own “servants” with extraordinary consideration. Perhaps because of their tolerant practices, the future legislator gained a measure of independence early in his life. The Nashville Union and American
(December 6, 1872) stated that in 1851, when Keeble was 18 years old, he took a job as “roller boy” on the Rutherford Telegraph
in Murfreesboro; by 1854 he was working as pressman for both the Telegraph
and the Murfreesboro News
. He may well have learned the trade under H. P. and Edwin Keeble, who owned the Murfreesboro Monitor
. Sampson worked for these newspapers until the Civil War, and then, according to an account in the Union and American (November 7, 1872), “he was in the Confederate lines during most of the war.” However, he was probably, if anything, serving as an aide or manservant to Horace Keeble rather than actually carrying arms. A Clarksville paper’s statement that “he shouldered his cooking utensils and went into the Southern army like a hero” suggests that he may have been taken along as a cook.
Home and employment in Nashville
This Tennessee Historical Commission marker commemorates the service of Sampson W. Keeble, “the first African-American to serve in the Tennessee General Assembly.” It stands near the intersection of Broadway and 2nd Avenue in downtown Nashville. (photo by Kathy Lauder)
By 1865 Nashville city directories show that Sampson Keeble had settled in Davidson County. He worked in a barbershop at 24 Cedar Street (today’s Charlotte Avenue) and took various part-time jobs to support himself; family members report that he also worked for some time as a custodian in a law office, where he became interested in studying law. The attorneys in that practice, reportedly impressed by his enthusiasm for learning, supported his efforts. He was eventually able to pass the Tennessee bar, which in those days did not involve a written examination, but instead required assessment and approval by a handful of legal professionals and, finally, confirmation by a sitting judge. Keeble’s legal training would later allow him to qualify for election as a Davidson County magistrate. Family members also believe he attended Fisk University briefly, although the university cannot locate his name in their records.
Keeble participated in “a meeting of colored men,” some of Nashville’s leading citizens, who met to quash rumors that the city’s African Americans were planning “a mob and Massacre.” The group, which also included William Sumner, Carroll Napier, Peter and Samuel Lowery, Henry Harding, Nelson Merry, and others, wrote a letter to city government officials, reprinted in the Republican Banner
, assuring them that the rumors were false, and that “the feelings of the colored people [were predisposed] toward peace and good order.”
Both Sampson Keeble and his brother George worked as barbers, along with several other Keebles (including a Wesley) who may have been relatives. Sampson eventually established the Rock City Barber Shop and managed it for about 20 years. (He was still listed as a barber in the Nashville city directory as late as 1885.) Barbershops of that era were strictly segregated: African American barbers were extremely popular with white customers, who still took considerable pleasure in being served and groomed by these deferential former slaves.
Many dramatic changes were taking place in the South during the early post-war years. Tennessee had returned to the Union with far fewer restrictions on its political structure than other Confederate states. The third state (July 19, 1866) to ratify the Fourteenth Amendment
, which granted citizenship status to African Americans, Tennessee was readmitted to the Union a week later, without ever having to conform to the stiff federal regulations most of its neighboring states faced during Reconstruction. Tennessee’s new constitution already included an anti-slavery clause, and, in less than a year (March 1867), the General Assembly would approve the right of African American men to vote and to hold political office – nearly three years before the passage of the Fifteenth Amendment
Keeble had been an active participant in the second State Colored Men’s Convention, which met in Nashville in August 1866 and organized daily demonstrations at the Capitol, lobbying legislators to approve their right to vote. It was that dogged pressure, backed by Governor William G. “Parson” Brownlow, who needed the help of black voters in order to win reelection, that convinced the legislature to change the law. Almost overnight African Americans saw a transformation in their civic status. On September 3, 1868, at the beginning of the Circuit Court session, the Nashville Republican Banner
published a story titled, “Negro Jurors – A Big Dose of Unadulterated African.” It listed the jurors for the coming term, including Sampson W. Keeble, James C. Napier, and six other African Americans. Keeble’s name also appeared on a list of Grand Jury members in April 1878 and of Federal Court jurors in March and April 1881.
By the time of the 1870 census Sampson Keeble had become the head of a large and complex household. He was the proprietor of the Harding House, a boarding house valued at $4000, a tidy sum for the period. This establishment stood near where the Ryman Auditorium is today. Keeping house was Eliza Keeble, 35, whom we know from their mother’s gravestone to be Sampson’s sister. The individual named Mary, 65, was probably Sampson and Eliza’s mother (usually called Nancy, although her gravestone, as well as this census record, says Mary). She described her occupation as “at home,” and was the only one in the family who unable to read and write. There were two children in the household: Hattie, 8 (ditto marks on the page suggest that her last name was Keeble, but in the 1880 census she was called Hattie Beckwith and identified as a niece), and “Saml” Keeble, Sampson’s son. His age is illegible. It appears to be 4, but is likelier to be 11. Two other women also reside with the family: Kate Beckwith, 22, and Harriet Keeble, 30. Harriet, Sampson’s first wife and the mother of young Samuel, was already an invalid. She died on June 16, 1870, shortly after this census was taken. Her funeral was held at the First Colored Baptist Church on West Martin (Pearl Street) near McLemore Street (10th Ave. N.), with the services conducted by H. S. Bennet and the Reverend Nelson G. Merry, who was the first African American minister ordained in Nashville as well as the founder of the Tennessee Colored Baptist Association. An 1872 Freedman’s Bank record for 13-year-old Thomas Keeble (this was apparently Samuel, since “Sammy” was scratched out and “Thomas” written above it on the form) gave his address as 116 North Cherry Street (today’s 4th Avenue), which was the site of Harding House, and he named as his parents Sampson W. and Harriet Keeble. (See image below.)
Keeble was believed to be among the wealthiest blacks in the city. An 1871 article in the Republican Banner
called attention to the fact that a watch stolen from him was evaluated at $100 (the equivalent of as much as $2,000 in 2011). Another article from 1871 suggests that he may have built up his wealth by being sternly frugal. In a squabble with a Market House merchant over the price of a turkey, Sampson Keeble was severely injured when vendor Byron Jackson struck him over the head with a cane. The Nashville Banner
reported that Keeble “was taken home mortally wounded,” and that, despite the efforts of physicians who discovered a compound fracture of the skull and “performed the operation of trepanning,” he was not expected to live.
In spite of such grave journalistic predictions, the plucky barber and boarding house proprietor not only survived his injuries but became even more intensely involved in civic affairs during the next two years. In July 1871 Keeble was named a director of the Tennessee Colored Agricultural and Mechanical Association, along with Henry Harding, William Sumner, Elias Polk, Abram Smith, Simeon R. Walker, Nelson Walker, John J. Cary, William Butler, J. W. Lapsley, J. L. Howard, Hiram C. Rhodes, and Oliver Thompson. This association ordered the construction of an amphitheater on the Colored Fairgrounds in preparation for the annual fair, scheduled to open on September 13. In May 1872 the Davidson County Chancery Court issued a decree granting the directors’ petition for incorporation of the association. In June of that year Keeble was re-elected a director as the group planned the next fair, which would open on September 15 and run for six days. Sampson Keeble, now clearly playing a leadership role in the African American community, served as treasurer of the Colored Agricultural and Mechanical Association and as a member of the advisory board of the Nashville Freedman's Savings and Trust Company Bank, one of only a handful of all-black Freedman’s Bank boards in the United States.
A petition was filed in Chancery Court on August 24, 1872, asking that the Freedman’s National Life Insurance Association be incorporated under the following directors: Nelson Walker, John J. Cary, Henry Harding, Abram Smith, Richard Howard, W. C. Napier, Sampson W. Keeble, and William Sumner. “The capital stock of the company is not to be less than $100,000, and may be increased to $250,000, to be divided into shares of $100 each.”
First African American elected to Tennessee General Assembly
Sampson Keeble offered his name as a Republican nominee for a seat in the General Assembly at a Party gathering in July 1869 but lost the nomination to J. H. Sumner, 51-33. He remained active in politics, and his intelligence and good nature won him many friends and supporters. In April 1870 he was on the committee that helped arrange a day of celebration after the adoption of the Fifteenth Amendment. Oddly, Tennessee, which already had a law on its books allowing black male citizens to vote, had voted against the Fifteenth Amendment. [In fact, Tennessee legislators did not ratify that amendment until the 100th General Assembly in 1997!]
The election year of 1872 was a busy time for Keeble. In March he was part of a group of barbers who signed a resolution calling for a state barbers’ convention to get to know one another, to provide for the widows and orphans of deceased members, and “to strive to ameliorate our condition too, and thus contribute our mite to the great work of elevation.” At the convention of the Davidson County Radical Republican Party that endorsed Ulysses S. Grant’s nomination, Sampson Keeble was appointed to the County Executive Committee and was elected as one of the seventeen delegates to the State Convention. In October the members of the Republican County Convention unanimously nominated Keeble, Captain James W. Ready, and Dr. Rudolph Knaffle to be “candidates for the Lower House of the General Assembly of Tennessee,” subject to the approval of the County Republican Executive Committee.
Sampson Keeble’s daughter Jeannette is pictured here with her husband, Benjamin F. Cox, principal of Avery Normal Institute in Charleston, South Carolina, from 1915 to 1936. Jeannette is holding their oldest son, Benjamin, born in 1906. (Photo courtesy of Helen Davis Mills)
A November 2 article in the Nashville Union and American
announced, “We have been furnished with one of the genuine Radical tickets for this county — variegated in color and in make-up.” The newspaper urged readers to “vote the straight tickets.”
Thus it was that in November 1872, riding the coattails of a sizeable popular vote for U. S. Grant for President, Sampson W. Keeble was narrowly elected, along with Dr. William P. Jones as Senator, and Philip Lindsley, J. B. Jeup, and James W. Ready as Representatives from Davidson County in the 38th Tennessee General Assembly
, which convened on January 6, 1873. Grant was enormously popular among black voters, so Keeble certainly picked up most of those votes, but he must have won a number of white votes as well, from people who found his moderate political stance acceptable. Unlike most other counties that elected black politicians during the next decade or so, Davidson County continued to retain a majority of white voters. Keeble became the first African American to serve as a member of the state legislature (and the last for some time – it would be eight years before another African American member took a seat in the House). The Nashville Union and American
reporter who wrote the story on November 7, 1872, was a little careless with his facts and rather ambivalent about Keeble’s victory:
The result of the election in this county is the complete success of the entire
Radical ticket. Davidson county is the first to elect one of our colored citizens.
Sampson W. Keeble is a barber by trade. He was formerly the slave of Hon.
Edwin Keeble, of Murfreesboro. He was in the Confederate lines during the
most of the war. Since the war he has resided in this city, and has deported
himself in a becoming manner for one of his station. Of the other representatives
elect we have Mr. Ready, an Irishman, Mr. Jeup, a German, and Mr. Lindsley, a native
Tennessean. So that on this ticket we have three nationalities and
two races. If our Legislature is intended to represent different nationalities or
different races, then the elected ticket is a decided success. If, however, it is intended
to represent the interests of the whole people of the State of Tennessee
with all their varied and important interests without regard to race or nationality
we are inclined to believe that the public judgment will be that our radical and “independent” Johnson opponents could have improved upon their ticket.
A cynical article from the Clarksville Weekly Chronicle
(January 25, 1873) provided some details of the situation Keeble faced in the legislature:
In the House, all solitary and alone, sits the Hon. S. W. Keeble, of Nashville
. . .. The “colored element” of Davidson would not permit itself to be overlooked—
it furnished a large proportion of the voters, and demanded representation—hence,
the Honorable Solon, or Solomon (I really forget which it
is), was the sop offered to the colored Cerberus . . . . It must be admitted that
the Hon S. W. Keeble bears his honors with meekness bordering on timidity.
Generally four members from the same county occupy but two double desks.
In this case the colored member has a “bunk” all to himself . . . . After all,
there are just seventy-three members, and somebody must be the odd member, and in this instance pleasure waits upon necessity with eagerness . . . . Keeble
has the advantage of a Southern birth and education, (he can read and write
after a fashion), and is less obnoxious on this account . . . . He is of low stature, rather heavy set, and, while he can undoubtedly claim an unmixed African descent, is of a ginger-cake complexion—a color which many Southern
negroes have somehow come by, perhaps rather by epidemic than by contagion . . . . He is evidently very lonesome, and looks as if he thought he was
doing something wrong . . . . One of the features of this case of rare complexion in Tennessee legislation, is the marked kindness accorded him by the ex-Confederate members: they declare their intention to hear attentively what he may have to say, and make him feel as easy as his exceptional and anomalous
position will allow . . . . But enough for the present of Mr. Keeble. As the
pioneer colored legislator of this State he is entitled to a prominence which
he will perhaps not enjoy again hereafter.
During his term in the legislature, despite such insults by the press and his apparent isolation in the House, Keeble valiantly introduced several bills aimed at bettering the condition of the African American community. One bill was intended to amend Nashville’s charter to allow blacks to operate businesses downtown; a second provided protection for wage earners (several black legislators of the 1880s would later follow his lead and introduce similar bills); and a third appropriated state funds to help support the Tennessee Manual Labor University. However, Keeble was unsuccessful at providing legislation to benefit his black neighbors, for none of his bills received a sufficient number of votes to pass into law. Keeble served only a single two-year term in the General Assembly and lost a later bid for re-election.
When writing about social events that included both black and white guests, several newspapers took note of a Nashville banquet to which Sampson Keeble was invited. According to the Dallas Morning News
, “In 1873 Gov. John C. Brown of Tennessee gave a banquet at the Maxwell House in Nashville and one of his guests was Sampson Keeble, a man of very black skin.” The Duluth News-Tribune
and the Kansas City Journal
said, “In Mr. Cleveland’s first administration the late Frederick Douglass was invited to one of the congressional receptions, together with his Caucasion [sic] wife, then his bride. And John C. Brown, the Democratic governor of Tennessee, as far back as 1873, when he gave a banquet at the Maxwell house, Nashville, had among the invited guests on that occasion the Hon. Sampson Keeble, a black negro representative from Davidshon [sic] county, who not only attended the banquet, but responded to a toast.”
The rise and fall of the Freedman’s Bank
A Freedman’s Bank record for Sampson Keeble’s son Thomas (called “Sam’l” in the 1870 census), a 13-year-old student at Bellview School. Thomas was the son of Sampson and his first wife, Harriet, who died in 1870. No further records of Thomas’s life have come to light. (Heritage Quest Online)
The concept of the Freedman’s Bank was first proposed by abolitionist John W. Alvord at a meeting with business leaders in New York in January 1865. Originally intended as a savings bank for the benefit of African American soldiers, its scope was broadened to include all former slaves and their descendants. Charles Sumner steered the bill quickly through Congress, and it was signed into law by President Lincoln five weeks later, on March 3, 1865. The bank was based in Washington, D.C., but branch offices quickly opened in seventeen states, including Tennessee. Sampson Keeble served from the beginning as a member of the advisory board of the Nashville Freedman's Savings and Trust Company Bank. Advertisements encouraged African American depositors, telling them the bank was chartered by Congress and misleading them into thinking their money was safely under the protection of the federal government. Unfortunately, however, despite the best efforts of Congress and newly appointed bank president Frederick Douglass, the bank had no choice but to close in 1874 because of “overexpansion, mismanagement, abuse, and outright fraud.” (Washington) African American depositors, many of whom had placed their life savings in Freedman’s accounts, were shocked to discover that the federal government did not protect the bank’s assets, and that they had lost everything. Local administrators, powerless to save their banks from the failure of the parent institution in Washington, D.C., petitioned Congress for help.
Sampson Keeble joined the Rev. Nelson Walker, Nashville entrepreneur Henry Harding, and other prominent Nashville citizens in sending a memorial to Congress. In their petition, they attempted to explain the magnitude of the fraud perpetrated on unlettered and trusting depositors by the bank, accusing it of
". . . appealing to a class of people who had been prevented by their
previous condition of servitude from accumulating wealth or even a
competency; and the principal, and in fact the effective, argument used
by the managers and agents of the institution to induce that poor, unlettered,
and trusting class to deposit their small earnings—the fruit of
their toil—in the institution was, that it was an institution chartered by
the Government, with its principal office at the seat of Government, and
that its funds, by express direction of Congress, (which the class appealed
to believed was a guarantee by Congress,) were to be invested in Government
securities. It is easy to see that the colored people, for whose benefit
Congress chartered this institution, would readily conclude that the Government
was bound or under some pledge which secured their deposits.
This may not be the law of the case, but it is certain that such representations
were made by the agents of the institution, and that the people who
placed their deposits in the bank believed that the Government was bound
for the deposits, or at least bound to see that the deposits were securely
invested in United States securities, and that this was a contract between
the United States and the depositor . . . .
There may be no legal obligation resting upon the Government to
guarantee [to those left in the unfortunate condition of having every dollar
most of them have in the world locked up in the payment of the amounts
they have deposited on the faith of their confidence in what they regarded
as the solemn pledge of the Government to have the funds of the institution
invested in the securities of the Government, but we respectfully urge that
there was and is a moral obligation resting on the Government to grant your
memorialists, and the other depositors in the institution, speedy relief by
assuming and paying the amounts due them; taking the assets of the bank,
and holding every other officer or agent of the institution who is liable,
civilly or criminally, to a strict responsibility for their acts."
Despite this passionate appeal, joined with similar petitions from other affected states, Congressional response was disappointing. Eventually, about half of the betrayed depositors received a fraction (60% or less) of the value of their accounts, while others lost everything they had saved. A number of depositors continued to petition Congress for years, hoping for reimbursement that never came. In the end, the African American community felt itself betrayed not only by the bank, but also by their government.
Civic and political activity
Sampson W. Keeble Jr., about 32, with his sister Jeannette Cox's children, Benjamin (4) and Helen (2). The photograph dates from about 1910, shortly before young Keeble moved to Detroit. (Photo courtesy of Helen Davis Mills)
As a result of Keeble’s membership on several boards and his political activism through-out the city, he was well known and admired within the African American community. After his legislative service, he was elected a magistrate in the Davidson County Court, serving from 1877 to 1882. His 1041-1022 victory in 1876 was contested on August 10 by his opponent, James W. Ready, his 1872 Republican running mate, who demanded a recount. After two days of counting Ready’s votes only, election officials announced that his total was 1,060, 19 more than Keeble’s original number. However, as the Daily American
pointed out, “Ready should have enjoined the Sheriff from issuing a certificate of election to Keeble, and thus had the matter decided before the returns were made to the authorities at the Capitol. As the Sheriff was not notified of Ready’s intention to contest the election, he gave Keeble a certificate of election, and the returns having been made to the Capitol, Keeble had no trouble obtaining his commission. . . . Ready’s only recourse is now through the courts.” When Ready challenged Keeble’s election in county court August 25, Judge John C. Ferris ruled that the commission could not be set aside once it was granted, and that Keeble should remain in office. Meanwhile, Keeble had asked that his own votes be recounted. This time his total was 1,066 – higher than Ready’s 1,060, after all. On August 22, in the midst of the recount process, Sampson Keeble had again been named a delegate to the State Republican Convention, along with A.V.S. Lindsley, Gen. George Maney, J. C. Napier, and Thomas A. Sykes
An attack on Keeble’s integrity was reported on November 15, 1878. A story in the Daily American
called “Colored Justice under Suspicion” told of the arrest of Keeble and two black police detectives on charges of “extortion and official oppression,” the second such charge against Keeble. It was not unusual for African Americans in positions of authority to be subjected to trumped-up charges by political opponents. It is apparent that these charges were also disproved, for Keeble continued to serve four more years as magistrate without interruption.
His cases were frequently covered by the “Courts” section of local newspapers. One can find articles, for example, recounting that he fined two women for breach of peace in 1877, jailed a man in 1878 for assault and battery, and ordered an inquest in the 1881 death of teenager Granville Bosley, who had been struck by lightning. In 1877 Keeble’s office was the site of a protest meeting of journeymen barbers, who initiated a strike for higher wages and more equitable working conditions.
Sampson Keeble ran again for the General Assembly in 1878 but was defeated by a Greenback party candidate, perhaps partly because the Democrats were beginning to regain their political supremacy in Davidson County by that time, and partly because racial violence and poll taxes were producing their intended effect of intimidating black voters, who failed to turn out at the polls in their usual numbers. Keeble remained active in city government, however, serving on a federal grand jury in 1881 and eventually being elected as a magistrate.
Marriage to Rebecca Cantrell Gordon
This photograph was taken on Sullivan’s Island, South Carolina. According to Keeble descendants, “cultured” African American women came here to give birth. Pictured clockwise from upper left are two unidentified individuals (perhaps friends or relatives), Rebecca Keeble holding her granddaughter Anna Rebecca, with Benjamin and Jeannette on the step below. It is likely the family had temporarily moved there from Charleston in 1914 to wait for Wendell’s birth. At one time Sullivan Island was the largest slave port in North America, the destination of more than 40% of all the slaves brought to the British colonies. As many as 200,000 slaves may have disembarked there. Some experts estimate that half of all African Americans living today are descendants of slaves who passed through Sullivan’s Island. (Photo courtesy of Helen Davis Mills)
By the time of the 1880 census, Sampson, now in his late 40s, was married to Rebecca Cantrell Gordon, a 29-year-old teacher (born August 24, 1849), who had been educated in New York; they were the parents of three-year-old “Jennie” (Jeannette) and one-year-old “S.W.” (Sampson W. Jr.). These were the only Keeble children who survived to adulthood. Several others, including a set of twins, died in infancy. (Five-month-old Charles Marshall Keeble died in November 1881; another son, born during the election year of 1884, was given the name James G. Blaine Keeble, but this child soon died as well.) In the 1910 census, Rebecca would report that only two of the six children to whom she had given birth were still living. Also residing in the Keeble household in 1880 were Sampson’s widowed mother, Nancy Keeble (78), and two young relatives, Hattie M. Beckwith (18, doubtless the 8-year-old Hattie “Keeble” of the previous census) and Maggie K. Smith (17), both of whom were attending school in Nashville. Everyone in the household except for Sampson was identified as “mulatto.”
Keeble’s wife Rebecca was the natural daughter of her mother Harriott’s slave-owner, Carroll McGuire [named on her death certificate], and was raised in her father’s home, with light duties as a household servant – a “foot slave.” It is quite possible that she was educated along with the other children of the household. Delighted by this clever little girl, her father sent her to live with relatives in Staten Island, New York, and she received an education there that included lessons in music and Latin. She eventually returned to Nashville (after a failed romance, according to family lore) where she began to teach other African Americans, both children and adults, to read and write. Even after the Civil War, a considerable number of people opposed education for blacks, and some extremists attempted to find and close black schools, which were often makeshift workshops held in churches and private residences. Rebecca continued to teach, in spite of threats to her safety, moving from place to place to meet with her students. Sampson Keeble fell in love with this beautiful and spirited young woman, more than 15 years his junior, and they were married about 1875. Family members say that both Sampson and Rebecca were avid readers who particularly loved reading the Bible.
Family life and children’s accomplishments
At some point, daughter Jeannette remembered, the family left Nashville for Marshall, Texas. However, they returned to Nashville a short time later when, as descendants tell the story, the passionately Republican Keeble “was run out of there for being a rabble-rouser.” Jeannette may have been remembering her father’s final years – he died in Fort Bend County, Texas, in 1887, when his children were still quite young. Rebecca returned to Nashville and continued to work after becoming widowed. She was a remarkable seamstress, and could knit, crochet, tat (make lace), and embroider expertly. Her name appeared in city directories from 1891 through 1918 in much the same form: “Keeble, Rebecca G (c), widow Samson W, seamstress,” and her address for much of that period was a boarding house at 1605 Jefferson Street. Her son Sampson W. Jr. lived with her until 1910 or 1911. Keeble descendants remember that he owned a high-wheeler (penny-farthing) bicycle as a young man. There were a number of these bicycles around Nashville during the 1880s, as well as clubs that encouraged their use.
Benjamin and Jeannette Keeble Cox, both graduates of Fisk University, were lifelong educators, spending many years at the helm of the Avery Institute in Charleston, South Carolina. Sampson Jr. appeared from time to time in Nashville city directories, working as a porter, a clerk, or a messenger (for the Duncan Hotel); his last Nashville census entry was recorded in June 1910, showing him to be single and living in Rebecca’s household. In August 1912 he took out a license in Detroit, Michigan, to marry Alice Criss, a woman who had been married once before. Keeble gave his age as 34, listed his occupation as janitor, named Sampson and Rebecca as his parents, and stated he had no previous marriages. C. Emery Allen, clergyman, officiated at the ceremony, held August 18, 1912. Unfortunately, when Sampson filled out his Draft Registration card in 1918 (medium height, medium build, brown eyes, black hair), his marriage seems to have ended. He listed Rebecca Keeble as his nearest relative, and his occupation as porter in the Hoffman Hotel in Detroit. Alice’s name appeared on another marriage license in July 1920; 40 years old by then, and marrying a 33-year-old laborer named Ralph Dixon, she said (for the second time!) that she had had only one previous marriage.
After her son moved north, Rebecca continued to work as a dressmaker. When her eyes failed, Jeannette and Benjamin Cox took her into their home in Charleston, where she could be near her beloved grandchildren. She died there tragically, early in 1923, when a gas stove in her room set her clothes on fire. Although family members rushed to her aid, they were too late to save her.
The last year the name of Sampson Keeble Sr. appeared in the Nashville City Directory
was 1886, when he was listed as a teacher. A brief obituary in the Nashville Daily American
on July 3, 1887, said, “The many friends of Sampson W. Keeble (formerly of Nashville) will regret to learn of his sudden death, which occurred in Richmond, Tex., June 19, caused by a congestive chill [probably a form of malaria]. He was born in Rutherford County May 18, 1833. He was 54 years old.”
It is not clear whether Sampson W. Keeble was buried in Texas or Tennessee. He is listed with his daughter and son-in-law, Jeannette Keeble and Benjamin F. Cox, on a grave-stone in Greenwood Cemetery on Elm Hill Pike in Nashville. The grave is on a piece of land that runs parallel to Spence Lane, directly across from the final resting places of R. H. Boyd, a Nashville publishing giant, and James C. Napier, the city’s first African American councilman and Register of the U.S. Treasury under President Taft. There is no grave for Rebecca, although her death certificate says that her body was returned to Nashville for burial on January 10, 1923, so it is probable that Sampson was already buried in that city. Sampson’s mother lies in the old Mt. Ararat Cemetery in Nashville, under a broken gravestone with this nearly illegible inscription:
State Honors Sampson Keeble in 2010
KEEBLE Born: 1805 Died: 1883
SACRED TO THE MEMORY OF
THE MO????OF S. W./ ELIZA A. CEORCEL
KITTY ????Y KEEBLE
CUMBERLAND CO. VA.
AUG. 20, 1805
DIED IN NASHVILLE
JAN. 16, 1883
LORD ? CHRIST
On Monday, March 29, 2010, a bust of Sampson W. Keeble, commissioned by the Tennessee Black Caucus of State Legislators, was unveiled outside the House Chamber in the State Capitol. Created by internationally recognized sculptor Roy W. Butler, the bust stands on a base of Tennessee pink marble engraved with the names of all fourteen African American legislators elected to the Tennessee General Assembly during the 19th century. The day-long ceremony
, which was attended by eight direct descendants of Sampson Keeble, included addresses by three historians, a slide show by Mr. Butler illustrating various stages in the production of the bust, a luncheon for family members and legislators at the historic Hermitage Hotel, and the unveiling of the statue, followed by a public reception and the reading of a proclamation in the House of Representatives honoring Keeble and the other 19th century black legislators.
Many thanks to Sampson Keeble family members Helen Davis Mills, Dr. Leonard Davis, and Dr. Wendell Cox Jr., who provided invaluable information for this biography. We are so very grateful for your continuing support.
Much gratitude also to Walter Keeble descendant Virginia G. Watson for sharing her research on the Keeble family.
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Watson, Virginia Gooch. The Keeble Family Genealogy
, 1986. Typescript in the collection of the Tennessee State Library and Archives.
, November 30, 1872.
Work, Monroe N. “Some Negro Members of the Tennessee Legislature During Reconstruction Period and After.” Journal of Negro History
, Vol. V, January 1920, 114-115.
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Could corals survive more acidic oceans?April 2nd, 2012 - 6:19 pm ICT by IANS
Sydney, April 2 (IANS) Corals may yet be able to survive the acidification of the world’s oceans, escaping the effects of climatic devastation.
Researchers have identified a powerful internal mechanism that could enable some corals and their symbiotic algae to counter the adverse impact of a more acidic ocean.
As humans release ever-larger amounts of carbon dioxide (CO2) into the air, besides warming the planet, the gas is also turning the world’s oceans more acidic, faster than those seen during past extinctions, the journal Nature Climate Change reports.
Scientists from Australia’s ARC Centre of Excellence for Coral Reef Studies (CoECRS) and France’s Laboratoire des Sciences du Climat et de l’Environnement, has shown that some marine organisms that form calcium carbonate skeletons have an in-built mechanism to cope with ocean acidification - which others appear to lack.
“The good news is that most corals appear to have this internal ability to buffer rising acidity of seawater and still form good, solid skeletons,” says Malcolm McCulloch professor at CoECRS.
“Marine organisms that form calcium carbonate skeletons generally produce it in one of two forms, known as aragonite and calcite,” adds McCulloch, according to a CoECRS statement
“Our research broadly suggests that those with skeletons made of aragonite have the coping mechanism - while those that follow the calcite pathway generally do less well under more acidic conditions,” said McCulloch.
- Fish learn to cope with high CO2 in oceans - Jul 03, 2012
- Carbon emissions speed up ocean acidification - Jan 23, 2012
- Oceans acidification peaks in 300 mn years - Mar 04, 2012
- Make more efforts to tackle rising ocean acidity, say European scientists - May 20, 2010
- Using Mother Nature's method to save oceans' marine life - Jan 20, 2011
- Cut global emissions to save coral reefs - Nov 18, 2009
- 'Rising CO2 levels threaten aquatic food webs' - May 08, 2012
- Radical methods needed to save oceans, say experts - Aug 21, 2012
- Carbon emissions lead to dangerous changes in oceans - Apr 02, 2010
- How climate change and pollution affect ocean chemistry - Jun 20, 2010
- High acidity levels in oceans harming marine life - Dec 05, 2010
- Weed-eating fish key to reef's survival - Mar 11, 2011
- Sea cucumbers could protect endangered corals - Feb 01, 2012
- Global warming threatens coral growth in Red Sea - Jul 16, 2010
- Acidic oceans endangering baby corals - Apr 19, 2012
Tags: acidic conditions, acidity, adverse impact, aragonite, calcite, calcium carbonate, calcium carbonate skeletons, centre of excellence, climate change reports, coping mechanism, coral reef, devastation, internal mechanism, journal nature, malcolm mcculloch, marine organisms, ocean acidification, reef studies, seawater, symbiotic algae
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West Nile Virus (WNV) causes a potentially fatal encephalomyelitis (inflammation of the brain and spinal cord) in a variety of species such as birds, horses, and humans.
This free report provides an overview of the disease and how it spreads as well as describing the clinical signs to watch for in your horses and other animals. Diagnosis and treatment options are discussed, as well as the prognosis of a horse with West Nile Virus and tips for preventing it.
- Veterinarians Urge Vaccination against West Nile Virus
- Increased Equine West Nile Virus Activity in 2012
- Horse Vaccines in 2012: Where We Stand
- EHV-1 Inactivated Vaccine Efficacy Tested (AAEP 2011)
- Equine Infectious Disease Control in Developing Countries
- Management Strategies to Enhance Vaccine Efficacy
- Researcher: Current Equine Flu Vaccines Effective Against Foreign Strains
- Vaccinating Pregnant Mares for Equine Viral Arteritis
- Spring Vaccinations: Points to Consider Before You Buy
- Possible Cause of Unusual Neurologic Signs in Australian Horses Identified
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Screening detects disease, therefore screening must be good. That simple mantra is, sadly, far from true, as the latest errors in cervical-smear screening programmes become apparent. Poor performance at the Kent and Canterbury Hospitals NHS Trust in the UK is one of the worst examples in a series of setbacks that have bedevilled such programmes since their inception in the late 1980s. 91 000 cervical smears collected during 1990-95 and examined in Kent were rechecked: 333 women at high risk of progressing to cervical cancer (which would have led to immediate follow-up) had been told their smears were normal. Eight have died of cervical cancer and 30 have undergone hysterectomies. Unsurprisingly, many are seeking legal advice with a view to compensation.
Detection of abnormal cells on the screening smear would have led to repeat testing, colposcopy, biopsy, and treatment, when appropriate. Therein lies the dilemma in any screening programme. The “correct answer” is that some proportion of the results will be incorrect, because no test is perfect.
The concept of false-positive and false-negative test results is a difficult one for the public to understand, but simple non-jargon explanations must be put across. In the UK programme, between the invitation to the first screen and the possibility of colposcopy and treatment, a woman can receive up to ten letters and four leaflets. Those screened deserve the most accurate answer any test can provide, but they also need to realise that tests are not completely accurate. The UK information leaflets and letters about cervical-smear testing are a model of research-based wording and design, yet only allude to the concept of a false test result, with little or no explicit explanation of what a false result means. For instance, a Health Education Authority leaflet states that “cervical screening is not 100 per cent perfect” and a new poster says that the smear test “cannot be 100 per cent accurate”.
Mass screening of the population is limited to potentially fatal diseases such as cancer (eg, cervical and breast in systematic screening programmes; colorectal and prostate in experimental or self-selection programmes), and receiving a false result has many consequences for the individual. A false negative means that the opportunity for investigation and treatment has been missed. A false positive means further and, commonly, invasive tests (and possible treatment) when neither is needed. In addition, there is immense psychological morbidity associated with a false-positive result in a cancer check, as the individual (and family) waits for further tests and results.
The UK screens over 4 million cervical smears a year. In nearly a tenth of the smears, the sampling is inadequate. During 1996-97, 91% of adequate smears were reported as negative. Estimates of prevented cases of cervical cancer range from 1000 to 4000 a year. The advocates of cervical-smear screening programmes can only estimate the benefits of testing, because the introduction of the programme was never tested in randomised trials.
One of the few who dares speak the unspeakable about screening is a Bristol-based public-health physician, herself involved in a smear-test screening programme. Angela Raffle came under fire for writing, in a research paper in The Lancet in June, 1995, that “much of our effort…is devoted to limiting the harm done to healthy women and to protecting our staff from litigation”. She concluded: “The screening programme is identifying one in ten young women as ‘at risk’ for a disease that is likely to affect one in many thousands”. She returned to the debate in a letter in our Jan 24 issue: “Screening has distorted public belief. In our desire for good population coverage we have said that screening is simple, effective, and inexpensive. In truth, it is complex, of limited effectiveness, and very expensive”.
If screened people are not adequately informed about the possibility of a false-negative result, it is little wonder that, when they get such a result, their next port of call is a lawyer. By that stage, they will not be interested in the distinction between a less than perfect test and less than perfect provision of a testing service, as provided at the Kent hospital.
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Northallerton lecture by descendant of key figure in US history
12:11pm Sunday 30th December 2012 in News
A DESCENDANT of a man who helped shape America's history, is set to give a talk.
Jeremiah Dixon was responsible for helping create America’s Mason-Dixon line, which divided the slave-owning Southern states from abolitionist Northern states during the civil war.
Jeremiah Dixon, from Cockfield, County Durham, was commissioned 250 years ago by King George III to help resolve a dispute over boundary lines between the English colonies of Maryland and Pennsylvania in the US.
Maryland had been founded in 1632 by the Calvert family from Kiplin Hall, North Yorkshire, as a refuge for English Catholics. About 50 years later, neighbouring Pennsylvania was created by the Quaker William Penn and inhabited by the more aggressive Puritans.
Although surveying was in its infancy, accurate boundary measurements were required to prevent continuing argument, so the royal astronomer at the Greenwich Observatory recommended his assistant Charles Mason and Jeremiah Dixon, from Cockfield to undertake a boundary survey.
It took five years and proved one of the great technological feats of the century.
The boundary became the Mason-Dixon, which defined the boundary of freedom for escaping black slaves and the dividing line between Southern and Northern states in the civil war.
Now one of his direct descendants, John Dixon, is to host a talk entitled Jeremiah Dixon; Revered in America, Forgotten at Home, for Northallerton and District Local History Society.
It will take place at the Sacred Heart Church Hall on Thirsk Road, Northallerton at 7pm on Tuesday, January 8. Non-members are welcome at a nominal admission charge of £2.50, while students under 18 will be admitted free.
Comments are closed on this article.
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With some European countries pledging money and all countries agreeing to a second commitment period under the Kyoto Protocol, chances of a deal brightened on the penultimate evening of the UN climate summit in Doha.
The deal, however, will be too weak to have any discernible impact on global warming. The World Meteorological Organization has just warned that concentration of carbon dioxide – the main greenhouse gas (GHG) that is warming the earth – is at a never-before level. The United Nations Environment Programme has warned that current commitments to arrest GHG emissions fall around 40% short of what is needed to keep temperature rise within two degrees Celsius. A recent World Bank study paints a frightful picture of a world that may be four degrees warmer than pre-industrial levels.
But representatives of 194 governments gathered in Doha for the annual summit of the UN Framework Convention on Climate Change (UNFCCC) continued their game of doing as little as possible to combat climate change. “We can only do what is politically acceptable back home,” said a member of the US delegation. Xie Zhenhua, Vice Chairman of China’s National Development and Reform Commission, was confident that there would be “an outcome that may not be to the liking of all, but can be accepted by all” governments.
That “balanced outcome”, as Xie put it, came after Britain, Germany, France, Sweden and Denmark announced that they would be paying poor nations to help combat climate change and move to a greener development path. Negotiators from developing countries were still struggling to put these pledges into the final agreement text. With the US, Canada, Japan, Russia and New Zealand firmly opposed to any such move, the outcome was uncertain.
But with a large part of negotiations completed for the second commitment period of the Kyoto Protocol – though crucial issues remained outstanding – Christiana Figueres, UNFCCC Executive Secretary, was confident that negotiations would not collapse, and the world could move towards an agreement under which all countries would make stronger commitments to fight climate change after 2020.
The current commitments under the protocol are very weak indeed, and many developed countries have not even made any pledge about the extent to which they will reduce their GHG emissions. Xie pointed out that the “question is ambition of emission reduction – it is now insufficient to keep warming under two degrees, as science says we need.” But BASIC countries – Brazil, South Africa, India and China – indicated that they were willing to move forward rather than derail negotiations.
In a post-2020 regime where all countries may have obligations to arrest GHG emissions, the question of equity will be paramount, said Mira Mehrishi, head of the Indian delegation. The US delegation has a very different notion of equity than that of developing countries – mainly India – and this is a likely sticking point in future negotiations.
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THE STARS and stripes were raised Monday in the the immediate Eastern Ohio area and elsewhere, but this didn't involve flags with 50 stars.
With flags having 15 stars and 15 stripes, Ohioans and others through the nation Monday were marking the 200th anniversary of the declaration of war for the War of 1812.
The Governor's War of 1812 Bicentennial Commission enlisted help from officials in all 88 counties to draw attention to this important time in the nation's history and Ohio's involvement in the three-year conflict.
ONE of most memorable reports related to United States' naval history stems from that war.
It was Master Commandant Oliver Hazard Perry's dispatch to Major Gen. William Henry Harrison when he reported, "We have met the enemy and they are ours - two ships, two brigs, one schooner and one sloop."
Perry's dispatch resulted from his victory over the British during the Battle of Lake Erie off the coast of Ohio in 1813. The victory opened up the Great Lakes region and land west of Ohio for settlers.
Harrison himself was saluted as a hero of the War of 1812. After the Battle of Lake Erie, he commanded the forces that defeated the British and American Indians, including Tecumseh, at the Battle of the Thames near Chatham, Ontario. The war in the Lake Erie area then effectively ended.
Incidentally, Harrison County takes its name from that illustrious officer who was the first U.S. president to have lived in Ohio.
Harrison isn't the only hero associated with that war and East Ohio even though the 1813 event occurred elsewhere. Johnny Appleseed, who planted apples in area counties, reportedly ran approximately 30 miles from Mansfield to Mount Vernon to warn about American Indian massacres and to obtain reinforcements. Some report that he rode a horse.
ANOTHER event during that war occurred in the Battle of Fort McHenry when Francis Scott Key was inspired because the flag with 15 stars and 15 stripes was still flying.
His memorable words are that the "rocket's red glare, the bombs bursting in air gave proof through the night that our flag was still there."
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A material made from fibers or thread by weaving, knitting, felting etc. as any cloth.
1. To make, build or construct by assembling parts or manufacturing.
2. To make from raw material.
External front of a building that faces the street or courtyard and is usually used to describe bigger, elegant buildings. Fašade materials include wood, brick, glass, masonry, aluminum, etc.
1. The side of a wall covering that faces away from the framing; for example in an A-B plywood panel, the face would be the A side.
2. An exterior, exposed surface on a structure.
3. Any surface of a thing.
4. The outward appearance of anything.
The dollar amount, shown on a document.
Exterior decorative surface, which is made of brick that is not rendered, painted or plastered and is made of various brick materials, including clay, to give a desired effect.
Applies to the direction of the grain on the face of a veneer-faced panel, which is also called the long dimension of the panel. Since the greatest strength and firmness is parallel to the face grain, it is normal to run the face grain across the supports.
Hardening process for the surface of materials. As an example, the hardening of carbon steel is accomplished by first heating the steel to approximately 1200 degrees F. and then it is immersed in powdered carbon. When some of the carbon is absorbed into the molecular structure of the steel, the surface or face of the steel is hardened.
Also referred to as the face ply, it is the outer layer when there are two or more layers. Face Line Lines that are made of strong string, which is stretched out and attached to staked boards, so that masons can follow the straightness of it when building masonry walls.
Nails, which are hammered at right angles (perpendicular) to the work surface. Also called direct nailing.
The side of the material where the weld was applied, which has the exposed weld.
Face plate holds the work to be turned on a lathe. The plate is then fastened to the lathe headstock, which is the part of the lathe that turns the work.
Also referred to as the face layer, it is the outer layer when there are two or more layers.
Additional weld material, which is added to the face of the weld.
Front of a concrete block.
Coverings, designed to protect the entire face of a worker when a sander, grinder, etc. are being used. A transparent eye panel allows the worker to be protected from small particles, which are being thrown, while being able to see.
The dollar amount shown on a document.
Measurement of the air velocity as measured at the face of the inlet or outlet in an HVAC system.
The outer veneer on a piece of plywood.
The front wall of a structure or, alternately, a retaining wall.
Masonry structure that has different types of material as backing and facing, such as brick on concrete, bonded together.
Veneer covered structural wall.
Real estate professional who aids in a transaction but does not have an agency relationship with that party and can be known as an intermediary or transaction broker.
1. Ease of doing or making; absence of difficulty.
2. A building or special room, constructed for a specific function.
1. Covering of contrasting material to decorate or protect a building; a finished wall surface.
2. Smoothing; finishing.
Specifically made brick, in a special color or texture, for the outside or facing wall of a building.
A reproduction or exact copy or architecturally a reproduction of a building style. Alternately, the electronic transfer of an exact image of a document or picture, referred to as a "fax".
The purchase of the accounts receivable of a business or alternately, taking the accounts receivable of a business as collateral for a loan.
The ratio of the maximum strength of a piece of material or a part to the probably maximum load to be applied to it. If a maximum of 2,000 pounds can be tolerated, a load of 500 pounds will have a 4 to one factor of safety.
The edge of any fabricated item that has been prepared in a factory, such as the long edge of wallboard panels, coming from a factory covered with paper. Fade.
1. To become less distinct. To lose color or brilliance.
2. To disappear slowly. To wane.
Also spelled faggot, the term refers to a bundle of sticks or branches to be used for fuel, or alternately, a bundle of iron or steel pieces to be hammered or rolled, at welding temperature, into bars.
Temperature measurement, named after its discoverer Daniel Fahrenheit 1686-1736, in which 32 degrees is the freezing point and 212 is the boiling point for water.
Italian glazed earthenware, as colorfully designed pottery or in blocks or tiles to be used as wall facings.
Federal law governing credit and charge card billing errors. If the credit card company violates this law, consumers can sue for damages.
A federal law that allows individuals to examine and correct information used by credit reporting services.
Federal law outlawing debtor harassment and regulates collections agencies, original creditor's collection offices (if separate) and creditor's lawyers. Original creditors may be covered under state law.
Federal law making it illegal to refuse to rent or sell to anyone based on race, color, religion, sex or national origin. 1988 amendments expanded protections to include family status and disability.
The rent a property commands in a free and open market setting.
Amount that could be received on the sale of real estate when there is a willing seller and buyer. It is a term generally used in property tax and condemnation legislation, meaning the market value of a property.
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Four voyages can lead to plenty of misadventure. Discover the places where Christopher Columbus met with high drama (and just a few setbacks) during his discovery of the New World, from 1492 to 1504.
Christmas Day 1492 wasn’t all glad tidings and good cheer for Christopher Columbus. On a journey to the northern coast of the Caribbean island of Hispaniola, one of Columbus’ 3 ships, the <i>Santa Maria</i>, ran aground and had to be abandoned. It was the first of Columbus’ 4 voyages to the Americas.
Columbus didn’t exactly get a warm welcome when he landed on the Samana Peninsula (in present-day Dominican Republic). He met with violent resistance from the Ciguayos, one of the nations of the Caribbean islands. Because of the Ciguayos' use of arrows, Columbus called the inlet where he encountered them the Bay of Arrows. Historians have since debated its exact location: Some say it is the Bay of Rincon, others that it is Samana Bay.
The good times kept on coming as Columbus headed for Spain, on the last leg of his first voyage. He soon had to put those plans on hold, as a storm forced his fleet into Lisbon. There Columbus anchored next to Portugal King John II’s harbor partrol ship. Columbus spent the next week in Portugal, before he was able to continue on to Spain.
Nine months later, Columbus once again set sail for the high seas. This time, on his second voyage, he returned to Hispaniola, where he intended to visit the fort of La Navidad (built during his first voyage). However, Columbus discovered that the fort, located on the northern coast of Haiti, had been destroyed by the native Taino people. Centuries later, in 1977, an amateur archeologist excavated artifacts from La Navidad.
It seemed like a good idea at the time. When Columbus sailed more than 60 miles eastward, along Hispaniola’s northern coast, he established the settlement of La Isabela, in present-day Dominican Republic. But in 1494 and then, in 1495, the settlement was struck by 2 North Atlantic hurricanes. Hunger, disease and mutiny soon followed, until Columbus abandoned the settlement altogether.
That's what Columbus was thinking when he arrived in Cuba (which he named Juana) on April 30, 1494. Exploring the island’s southern coast, Columbus placed his bets that it was part of a peninsula connected to mainland Asia.
And this must be the Garden of Eden! That’s what Columbus concluded as he sailed the Gulf of Paria (between present-day Trinidad and Venezuela). The nice climate, the abundance of food, the friendliness of the natives and the richness of the area’s natural resources all led him to that conclusion. He also wagered that, based on the rotation of the pole star in the sky, the Earth must not be perfectly spherical, but rather bulged out like a pear around the new-found continent we now know as South America.
Columbus wasn’t feeling so well when he returned to Hispaniola on Aug. 19, 1498, during his third voyage. He felt even worse when he discovered that many of the Spanish settlers of the new colony were in rebellion against his rule, saying that Columbus had misled them about the supposedly bountiful riches of the New World.
Columbus’ fourth and final voyage met with choppy waters in June 1502. When his fleet arrived in Santo Domingo, it was denied port by the new governor. But Columbus got his revenge. He told the governor a storm was coming. The gov didn’t listen … to his demise. He ended up surrendering to the sea, along with 29 of his 30 ships.
Columbus’ 4 ships took a bruising while cruising through present-day Panama. Locals had told Columbus about gold and a strait to another ocean. Columbus set out on an exploration and established a garrison at the mouth of Panama’s Belen River. In April 1503, one of Columbus’ ships became stranded in the river. Meanwhile, the garrison was attacked by the Guaymí locals. Further headaches followed when shipworms damaged the ships at sea.
Columbus’ ships sustained further damage when a storm hit off the coast of Cuba. Unable to travel on, the fleet was beached in St. Ann’s Bay, in Jamaica. For 1 year, Columbus and his men remained stranded in Jamaica before help arrived. In all, Columbus’ voyages stretched over 12 years, and -- a few misadventures aside -- opened the door to the “New World."
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The placenta is the link between you and your baby. When the placenta does not work as well as it should, your baby can get less oxygen and nutrients from you. As a result, your baby may:
- Not grow as well
- Show signs of fetal stress (this means the baby's heart does not work normally)
- Have a harder time during labor
Placental dysfunction; Uteroplacental vascular insufficiency; Oligohydramnios
Causes, incidence, and risk factors
The placenta may not work as well due to pregnancy problems or habits in the mother, such as:
Certain medications can also increase the risk of placenta insufficiency.
In some cases, the placenta:
- May have an abnormal shape
- May not grow big enough (more likely if you are carrying twins or other multiples)
- Does not attach correctly to the surface of the womb
- Breaks away from the surface of the womb or bleeds
A woman with placental insufficiency usually does not have any symptoms.
Signs and tests
The health care provider will measure the size of your growing womb (uterus) at each visit, starting about halfway through your pregnancy.
If your uterus is not growing as expected, a pregnancy ultrasound will be done. This test will measure your baby's size and growth, and assess the size and placement of the placenta.
Other times, problems with the placenta or your baby's growth may be found on a routine ultrasound that is done during your pregnancy.
Either way, your doctor will order tests to check how your baby is doing. The tests may show that your baby is active and healthy, and the amount of amniotic fluid is normal. Or, these tests can show that the baby is having problems.
If there is a problem with the placenta, you and your doctor must decide whether to induce labor.
You may be asked to keep a daily record of how often the baby moves or kicks.
The next steps your doctor will take depend on:
- The results of tests
- Your due date
- Other problems that may be present, such as high blood pressure or diabetes
If your pregnancy is less than 37 weeks and the tests show that your baby is not under too much stress, your doctor may decide to wait longer. Sometimes you may need to get increased rest on your side. You will have tests often to make sure your baby is doing well. Treating high blood pressure or diabetes may also help improve the baby's growth.
If your pregnancy is over 37 weeks or tests show your baby is not doing well, your doctor may want to deliver your baby. He or she may induce labor, or you may need a c-section
Problems with the placenta can affect the developing baby's growth. The baby cannot grow and develop normally in the womb if it does not get enough oxygen and nutrients.
When this occurs, it is called intrauterine growth restriction
(IUGR). This increases the chances of complications during pregnancy and delivery.
Getting prenatal care early in pregnancy will help make sure that the mother is as healthy as possible during the pregnancy.
Smoking, alcohol, and other illicit drugs can interfere with the baby's growth. Avoiding these substances may help prevent placental insufficiency and other pregnancy complications.
Baschat AA, Galan HL, Ross MG, Gabbe SG. Intrauterine growth restriction. In: Gabbe SG, Niebyl JR, Simpson JL, eds. Obstetrics: Normal and Problem Pregnancies. 6th ed. Philadelphia, Pa: Saunders Elsevier; 2012:chap.31.
Grivell RM, Wong L, Bhatia V. Regimens of fetal surveillance for impaired fetal growth. Cochrane Database Syst Rev. 2009;(1):CD007113.
Farinelli CK, Wing DA. Abnormal labor and induction of labor. In: Gabbe SG, Niebyl JR, Simpson JL, eds. Obstetrics: Normal and Problem Pregnancies. 6th ed. Philadelphia, Pa: Saunders Elsevier; 2012:chap.14.
Linda J. Vorvick, MD, Medical Director and Director of Didactic Curriculum, MEDEX Northwest Division of Physician Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington; and Susan Storck, MD, FACOG, Chief, Eastside Department of Obstetrics and Gynecology, Group Health Cooperative of Puget Sound, Bellevue, Washington; Clinical Teaching Faculty, Department of Obstetrics and Gynecology, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.
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(Continued from page 1)
Grow ripe fruit.
Before plucking seeds, the plant’s fruit should be grown to its ripest point. For beans and peas, this is far beyond the normal harvest time—well after pods have swollen and begun to dry.
Collecting seeds for saving is easiest for beans and peas, which can be removed from dried pods like shell beans. Tomatoes are a different story. Fruit must be picked when ripe and then squeezed to capture both seeds and slimy juice in a plastic container.
Allow seeds to sit in the juice.
Seeds must ferment in the juice for several days to remove a gel coating that hinders germination. Place the container outside to avoid the smelly fermentation process, but keep the seed container away from direct sun. In a few days, a foul-smelling scum will form on the surface.
Leave the seeds in the scummy soup for another day or two before pouring off the scum and lightly rinsing the seeds. Toss out any seeds that are afloat after the other seeds have settled to the bottom. Dry the seeds on paper plates or napkins labeled with each variety. Allow them to cure indoors (out of direct sunlight) for an additional week before packaging them in labeled paper envelopes. Store the envelopes in a cool, dry location.
About the Author: Andy Tomolonis is a writer and gardener in suburban Boston.
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(adj) far (at a great distance in time or space or degree) "we come from a far country"; "far corners of the earth"; "the far future"; "a far journey"; "the far side of the road"; "far from the truth"; "far in the future"
(adj) far (being of a considerable distance or length) "a far trek"
(adj) far (being the animal or vehicle on the right or being on the right side of an animal or vehicle) "the horse on the right is the far horse"; "the right side is the far side of the horse"
(adj) far (beyond a norm in opinion or actions) "the far right"
(adj) further, farther (more distant in especially degree) "nothing could be further from the truth"; "further from our expectations"; "farther from the truth"; "farther from our expectations"
(adv) far (to a considerable degree; very much) "a far far better thing that I do"; "felt far worse than yesterday"; "eyes far too close together"
(adv) far (at or to or from a great distance in space) "he traveled far"; "strayed far from home"; "sat far away from each other"
(adv) far (at or to a certain point or degree) "I can only go so far before I have to give up"; "how far can we get with this kind of argument?"
(adv) far (remote in time) "if we could see far into the future"; "all that happened far in the past"
(adv) far (to an advanced stage or point) "a young man who will go very far"
(adv) further, farther (to or at a greater extent or degree or a more advanced stage (`further' is used more often than `farther' in this abstract sense)) "further complicated by uncertainty about the future"; "let's not discuss it further"; "nothing could be further from the truth"; "they are further along in their research than we expected"; "the application of the law was extended farther"; "he is going no farther in his studies"
(adv) further (in addition or furthermore) "if we further suppose"; "stated further that he would not cooperate with them"; "they are definitely coming; further, they should be here already"
(adv) farther , further (to or at a greater distance in time or space (`farther' is used more frequently than `further' in this physical sense)) "farther north"; "moved farther away"; "farther down the corridor"; "the practice may go back still farther to the Druids"; "went only three miles further"; "further in the future"
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Is your child waking up in the middle of the night frightened and screaming? These unsettling sounds may cause alarm, especially when they occur frequently. I’d like to help you understand the difference between nightmares and night terrors and how to help your child cope in my two-part series, “Bad Dream Woes.” Karen Rogers, PhD, Psychologist and Program Area Leader for Project HEAL, a comprehensive therapeutic service for children exposed to trauma and their families at Children’s Hospital Los Angeles, to provide insight on how you can help your child.
What is a Nightmare?
Nightmare is another word for “bad dream.” It’s a type of sleep disruption characterized by frightening dreams in which your child feels threatened and develops a sense of physical danger. An example would be dreaming of being chased by a stranger or monster. Nightmares more commonly to occur in the early morning and happen during the dream phase of sleep, known as rapid eye movement (REM) sleep.
|Nightmares are a common experience for people
of all ages, and are normal for children to have.
Nightmares are most common in preschoolers (children aged 3-6 years of age). This is the age when normal fears develop and a child’s imagination is very active. Nightmares may involve disturbing themes, images or figures such as monsters, ghosts, animals or bad people. While this intense sense of fear ultimately causes your child to wake up on their own, it does not involve any physical danger.
The following behaviors are usually present in a normal nightmare episode:
- Your child wakes up during the last cycle of their sleep or early morning.
- Your child is frightened and triggers a partial or full awakening in which they are fully alert.
- Your child can describe the frightening dream in detail.
- Your child seeks and responds to comfort and reassurance from you or other close relatives.
- Your child shows fear of the scary dream happening again and may resist returning to bed.
What Triggers a Nightmare?
If your child is stressed or exposed to stressful situations, nightmares may begin to occur. Some stressful events include moving neighborhoods, changing schools, the birth of a sibling or parental marital problems. Other triggers may include being bullied at school or online, watching a scary movie, a recent injury or illness, the death of a loved one or physical, verbal or sexual abuse.
Help Your Child Keep Nightmares Away
When your child has an increase in nightmares, it’s a sign they are under emotional distress, feeling overwhelmed and insecure. Karen Rogers, PhD, emphasizes a number of simple ways to help your child feel better when they
|“Children of all ages will benefit from physical comfort and reassurance from their caregivers when frightened by a nightmare, such as hugs, being held, having a back rub. Speaking to a child in a soft, calm voice and reminding them that you are there to protect them, they are safe, that dreams aren’t real can also be helpful.”|
Creative Ways to Ward-off Nightmares
Rogers explains that once a child participates in imaginary play, they become better at using their imagination to combat nightmares. Here are some unique ways to keep nightmares at bay.
- Use “Monster Spray.” Label a spray bottle and fill with tap water. Spray around your child’s room for protection before bed time.
- Hang a warning sign on your child’s bedroom door, “No Monsters Allowed!” This can be enough to calm some fears for many children.
- Make a “dream catcher” together.
- Your child can choose a “protective” stuffed animal to sleep with.
- Help your child imagine a different and comforting ending to their nightmare.
- Rehearse the new ending before your child goes to bed so they know to use the comforting ending if the nightmare comes back.
If your child comes-up with their own creative way to keep nightmares away, it’s usually the most successful.
These simple strategies have worked for many children. If your child is constantly having nightmares and shows an ongoing fear of going to bed, Rogers stresses speaking with a pediatrician or counselor to seek more support.
What are some ways you’ve helped your child cope with nightmares? I’d love to hear what works for your
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)A local-area network (LAN) that uses a star topology in which all nodes are connected to a central computer. The main advantages of a star network is that one malfunctioning node doesn't affect the rest of the network, and it's easy to add and remove nodes. The main disadvantage of star networks is that they require more cabling than other topologies, such as a bus or ring networks. In addition, if the central computer fails, the entire network becomes unusable.
Standard twisted-pair Ethernet uses a star topology.
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Updated: January 10, 2012
Controlling land clearing
The Northern Territory (NT) is home to the core of the world’s largest tropical savanna on Earth. The woodlands and grasslands of the NT store billions of tonnes of carbon. Land clearing laws in Queensland and NSW helped cut those states’ carbon pollution levels significantly over the past decade.
Stopping major land clearing is fastest and cheapest way to achieve deep cuts in carbon emissions, as well as protecting wildlife, soil and river health. Not only will this protect the unique environment of the NT, but underpins the livelihoods and prosperity of river communities and businesses now and for future generations.
In December 2008 the NT Labor Government committed to pass a Native Vegetation Management Act that is ‘world’s best’ practice by mid 2010, including placing caps on land clearing. But to date this has not been delivered, despite key stakeholders, including members of the Daly River Management Advisory Committee, Amateur Fishermens' Association of the Northern Territory and Traditional Owners in the Daly River Catchment supporting a streamlined and effective approach to regulating the clearing of native vegetation.
The existing parallel processes under the Planning Act and Pastoral Lands Act is duplicative and outdated. The NT Climate Change Policy commits to maintaining native vegetation as a carbon bank, and maintaining the NT as a low land clearing jurisdiction. The consultation draft Native Vegetation Management Bill was provided to key stakeholders, including NT Cattlemens Association and NT Agricultural Association, in March 2011.
Passing a Native Vegetation Management Act and capping land clearing at low levels is the single most significant environmental reform NT Labor could achieve in this term of Parliament.
We are campaigning for all political parties to commit to stopping major land clearing by:
- Committing to pass a strong Native Vegetation Management Act,
- Announcing annual and long term caps on clearing that ensure annual rates of clearing are very low and trend downward over time, and
- Ensuring Indigenous communities are not excluded from potential future sustainable development through ‘Indigenous reserves’ within the caps.
For more information, please contact:
The Wilderness Society Inc
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This is a picture of the Colorado River near Hoover Dam.
Click on image for full size
Rivers are very important to Earth because they are major forces that shape the landscape. Also, they provide transportation and water for drinking, washing and farming. Rivers can flow on land or underground in deserts and seas. Rivers may come from mountain springs, melting glaciers or lakes.
A river's contribution to the water cycle is that it collects water from the ground and returns it to the ocean. The water we drink is about 3 billion years old because it has been recycled over and over since the first rainfall.
A delta is where a river meets the sea. Usually the river flows more slowly at the delta than at its start because it deposits sediment. Sediment can be anything from mud, sand and even rock fragments. A special environment is created when the fresh water from the river mixes with the salty ocean water. This is environment is called estuary.
The longest river is the Nile River in Africa, and the Amazon River in South America carries the most water. The muddiest river is the Yellow River in China.
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We have beautiful specimens of banded iron formation
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The water at the ocean surface is moved primarily by winds. Large scale winds move in specific directions because they are affected by Earthís spin and the Coriolis Effect. Because Earth spins constantly,...more
Sneeze into a pile of dust and the particles fly everywhere. Sneeze into a pile of rocks and they stay put. Thatís because they have more mass. You need more force than a sneeze to move those rocks. Wind...more
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Rivers are very important to Earth because they are major forces that shape the landscape. Also, they provide transportation and water for drinking, washing and farming. Rivers can flow on land or underground...more
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Changing Planet: Black Carbon
Black carbon contributes to global warming in two ways. When in the atmosphere, it absorbs sunlight and generates heat, warming the air. When deposited on snow and ice, it changes the albedo of the surface, absorbing sunlight and generating heat. This further accelerates warming, since the heat melts snow and ice, revealing a lower albedo surface which continues to absorb sunlight - a vicious cycle of warming.
Click on the video at the left to watch the NBC Learn video - Changing Planet: Black Carbon.
Lesson plan: Changing Planet: Black Carbon - A Dusty Situation
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is a fun group game appropriate for the classroom. Players follow nitrogen atoms through living and nonliving parts of the nitrogen cycle. For grades 5-9.
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Earth’s climate is warming. During the 20th Century Earth’s average temperature rose 0.6° Celsius (1.1°F). Scientists are finding that the change in temperature has been causing other aspects of our planet...more
This picture shows a part of the Earth surface as seen from the International Space Station high above the Earth. A perspective like this reminds us that there are lots of different things that cover the...more
Arctic sea ice is covered with snow all winter. Bright white, the snow-covered ice has a high albedo so it absorbs very little of the solar energy that gets to it. And during the Arctic winter, very little...more
Altocumulus clouds (weather symbol - Ac), are made primarily of liquid water and have a thickness of 1 km. They are part of the Middle Cloud group (2000-7000m up). They are grayish-white with one part...more
Altostratus clouds (weather symbol - As) consist of water and some ice crystals. They belong to the Middle Cloud group (2000-7000m up). An altostratus cloud usually covers the whole sky and has a gray...more
Cirrocumulus clouds (weather symbol - Cc) are composed primarily of ice crystals and belong to the High Cloud group (5000-13000m). They are small rounded puffs that usually appear in long rows. Cirrocumulus...more
Cirrostratus (weather symbol - Cs) clouds consist almost entirely of ice crystals and belong to the High Cloud (5000-13000m) group. They are sheetlike thin clouds that usually cover the entire sky. The...more
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Learn something new every day More Info... by email
A predicate is part of a sentence or clause in English and is one of two primary components that serves to effectively complete the sentence. Sentences consist of two main components: subjects and predicates. Subjects are the primary “thing” in a sentence which the rest of the words then describe through either a direct description or by indicating what type of action that subject is performing. The predicate is this secondary aspect of the sentence and usually consists of a verb or adjective, though complicated sentences may have multiple verbs and a number of descriptions affecting the subject.
It can be easiest to understand predicates by first understanding subjects and how sentences are constructed. A sentence just about always has a subject, though it can be implied in some way and not necessarily directly stated. In a simple sentence like “The cat slept,” the subject is “the cat,” which is a noun phrase consisting of the direct article “the” and the noun “cat.” Subjects can be longer and more complicated, but they are usually fairly simple in nature.
The predicate of a sentence is then basically the rest of the sentence, though this is not always the case for longer and more complicated sentences. In “The cat slept,” the predicate is quite simple and merely consists of the word “slept.” This is simple because “slept” is an intransitive verb, which means that it requires no further description or objects to make it complete. The sentence could be expanded as “The cat slept on the bed,” but this is not necessary and merely adds a descriptive component to the predicate through the prepositional phrase “on the bed.”
In a somewhat more complicated sentence, such as “The man gave the ball to his son,” the subject of the sentence is still quite simple: “The man.” The predicate in this sentence, however, has become substantially more complicated and consists of the rest of the sentence: “gave the ball to his son.” This has been made more complicated because the verb “gave” is transitive, specifically ditransitive, which indicates both a direct object and an indirect object.
The act of “giving” requires that there is a direct object, which is the item given, and an indirect object, which is who or what it is given to. In this instance, the predicate consists of the verb “gave” and the direct object “the ball” with a connecting preposition “to” and the indirect object “his son.” Predicates can become even more complicated as an idea expands, such as a sentence like “The rock rolled off the table, landed on top of a skateboard, and proceeded to roll down the hill until it was stopped by a wall.” In this sentence, the subject is only “The rock,” which means that the rest of the sentence is the predicate.
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About 15 to 20 years ago, folks began to notice problems in amphibian communities around the world. At first, physical deformities were being noticed and then large population declines were being documented.
The finger was initially pointed at the coal industry, with an idea that perhaps mercury was leading to the deformities. But this didn’t pan out. Next, farm practices came under fire, as excess fertilizer running off into farm ponds became the leading suspect. But that theory didn’t hold water either. Then, attention turned to the ozone hole, with the idea that increased ultraviolet radiation was killing the frogs. No luck there either.
Then came the Eureka moment—aha, it must be global warming!
This played to widespread audiences, received beaucoup media attention and, of course, found its way into Al Gore’s An Inconvenient Truth.
But, alas, this theory, too, wilted under the harsh glare of science, as new research has now pretty definitively linked an infection of the chytrid fungus to declines, and even local extinctions, of frog and toad species around the world.
Perhaps the biggest irony in all of this, is that while researchers fell all over themselves to link anthropogenic environmental impacts to the frog declines, turns out that as they traipsed through the woods and rainforests to study the frogs, the researchers themselves quite possibly helped spread the chytrid fungus to locations and populations where it had previously been absent.
Now a bit good—although hardly unexpected—news is coming out of the frog research studies. Some frog populations in various parts of the world are not only recovering, but also showing signs of increased resistance—gained through adaptation and/or evolution—to the chytrid fungus.
The magazine New Scientist has an interesting article titled “Fungus out! The frog resistance is here” that ties together a growing number of research findings indicating that frog populations that once faced local extinction have been making a come back—even in the continued presence of the chytrid fungus.
New Scientist reports that Australian researchers are reporting that a variety of frog species from across the Land Down Under that were once devastated by chytrid infection are now re-establishing themselves in areas that they were wiped out and in some cases have even returned to numbers as large as they were prior to the chytrid outbreak.
Other researchers are finding, as reported in the Proceedings of the National Academy of Sciences (Briggs et al., 2010), that frogs in the mountains of California that were once “driven virtually to extinction” are also making a recovery even though the chytrid fungus is still present. Some populations there have apparently developed the ability to survive in the presence of low-levels of the fungus.
Evidence of a developing resistance to the chytrid fungus has also been reported in a species of Australian frogs. A study published in the journal Diversity and Distributions (Woodhams et al., 2010) looked at populations of frogs which have recovered from a chytrid infection and found indications that natural selection may have led to more resistant populations and facilitated the recovery.
All this is not to say that amphibian populations across the world have made a full and complete recovery, but it is to say that there are encouraging signs that some populations are clawing their way back through adaptation and natural selection—precisely the way things are supposed to work.
And even though global warming is no longer considered to be the guilty party (of course, exonerated with much less fanfare than it was accused), the amphibian story does show the resiliency of nature—a resiliency that is grossly underplayed or even ignored in virtually all doom and gloom presentations of the impacts of environmental change.
Something that is worth keeping in mind.
Briggs, C. J., et al., 2010. Enzootic and epizootic dynamics of chytrid fungal pathogen of amphibians. Proceedings of the National Academy of Sciences, 107, 9695-9700.
Woodhams, D.C., et al., 2010. Adaptations of skin peptide defenses and possible response to the amphibian chytrid fungus in populations of Australian green-eyed treefrogs, Litoria genimaculata. Diversity and Distributions, 16, 703-712.
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Location: Northern Greece, Macedonia
The vardar is a cold northwesterly wind blowing from the mountains down to the valleys of Macedonia. A type of ravine wind, enhanced by a channelling effect while blowing down through the Moravia-Vardar gap, bringing cold conditions from the north to the Thessaloniki area of Greece. Most frequent during winter, it is blowing in the rear of a depression when atmospheric pressure over eastern Europe is higher than over the Aegean Sea. In general, the vardar is similar to the mistral wind.
A strong vardar event occured on January 12 and 13, 2003. Compare the significant drop in maximum temperature by 17°C (from 19C down to 2C) with the darstic jump in prevailing wind direction from easterly to northerly and northwesterly, and the wind speed and peak gusts during this time period recorded at Thessaloniki.
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This year’s national nursing week will take place May 7-13.
In 1971 the International Council of Nurses designated May 12, Florence Nightingale’s birthday, as International Nurse’s Day. Several years later, the first national nursing week was celebrated in 1985 to highlight nurse’s contributions to the well being of Canadian public.
As many of you know, Nightingale is best known around the world as the “lady with the lamp” who nursed British soldiers during the Crimean war and turned nursing into a profession. Nightingale died on August 13, 1910 at the age of90.
Prior to the founding of modern nursing, nuns and the military usually provided nursing-like care. The religious and military roots are still evident today in many countries, for example in the United Kingdom, senior female nurses are known as Sisters.
Although the event is celebrated internationally, Canada chooses to hold theirs independently on a different date.
The 2012 Canadian theme is Nurses- The Health of our Nation. It reflects the positive impact nurses make to the lives and well-being of Canadians.
Canadian nursing dates all the way back to 1639 in Quebec with the Augustine nuns. These nuns were dedicated to opening up a Mission that cared for spiritual and physical needs of patients. This Mission later went on to create the first nursing apprenticeship training in North America.
At the end of the nineteenth century, hospital care and medical services had been improved and expanded due to Florence Nightingale who was training women in English Canada. In 1874 the first formal nursing training program was started at the General and Marine Hospital in St. Catharines in Ontario. Many programs popped up in hospitals across Canada after this and graduates and teachers from these programs began to fight for licensing legislation and for professional organizations for nurses.
More changes began to occur after World War II, the health care system expanded and Medicare was introduced.
Registered nurses are extremely important for smaller communities, as many only have one doctor. In Canada we are lucky enough to have nurses who are legally allowed to prescribe medication.
Currently there are approximately 260,000 nurses in Canada but nurses are becoming scarcer and the population of baby boomers is aging which requires more nursing care.
The only major event mentioned on the Nursing Association’s web site was that of National telehealth education which was held at the Regina General Hospital, May 9.
Take a few moments to honor your community’s nurses. Say thanks, or give them a small sentimental gift in appreciation for what they do on a daily basis.
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|Module 3: Interpreting Data|
2. Using data to support an argument
To test a theory or answer a question a study is designed, sampling is conducted and the data is collected. The process of descriptive statistics then involves presenting the data in tables and graphs. The data may seem to indicate a clear conclusion about the population which has been sampled. But how strongly do the data support that conclusion? Is there strong evidence for the link between data and conclusion? How can you be sure that the effect observed is due to the experimental treatment and is not just an accidental result?
Deciding on the strength of the link between data - and making conclusions about the population - involves interpretation. The basis of how to make interpretation lies in another statistical process called inferential statistics. Inferential statistics involves the use of statistical methods and models to make measurable claims about populations (and population parameters) on the basis of samples (and sample statistics).
Usually researchers do not know the value of population parameters - they have to estimate them. But they do have measurements made on a sample -these are sample statistics. Researchers also realise that if they used a different sample from the same population to produce more data, the new sample statistics would be different to the first ones.
Inference uses probability to account for this sample variability. However, to make inferences you need to have designed a reliable, unbiased study so that the data that are produced are accurate and valid. Therefore, in order to make useful interpretations about data, or to assess the appropriateness of other interpretations, you need to first ask about how the data were produced and presented.
This page last updated 31 August 2009
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Description - Surrounded by the rugged foothills of the Appalachian Plateau, Tar Hollow State Park and surrounding state forest are characteristic of the wilderness that blanketed Ohio in the days of early settlers. It is a stronghold for many exciting species of wildlife. Numerous reptiles and amphibians, colorful game birds, songbirds and secretive mammals can be found here.
Copyright: Ohio Department of Natural Resources
Tar Hollow State Park
In the 1930s, the Tar Hollow region was purchased for conservation purposes under a New Deal program, the Ross-Hocking Land Utilization Project. People were given a new financial start in life and were encouraged to move to the cities. Most, however, bought more poor ground outside the park and continued to live as they always had.
During the Depression years, the WPA and NYA programs built recreation facilities including the 15-acre Pine Lake and group camp. In 1939, the Ohio Division of Forestry accepted operational control of the land that was then known as Tar Hollow Forest-Park.
When the Ohio Department of Natural Resources was created in 1949, the Division of Parks and Recreation accepted land of several state agencies including the old Division of Forestry. Tar Hollow State Park was developed from the earlier forest. The park, today, is bordered by Tar Hollow State Forest -- Ohio's third largest state forest.
- Tar Hollow State Park offers a campground set amid a wooded hollow near Pine Lake. There are 28 electric sites and 60 non-electric. Both sunny and shaded site are available. The campground is equipped with showers, pit latrines, dump station, and pet sites. A group camp is also available to organized groups. Additionally, five shelters permit camping.
Ross Hollow Hiking Trail, located near the camp, provides foot access to the hills of Tar Hollow. The 21-mile Logan Boy Scout Trail (red blazes) traverses the park and forest. A section of Ohio's Buckeye Trail (blue blazes) also passes through the area. Bridle trails and a horse camp are located on the forest land. A backpack camp is located at the fire tower.
Picnicking is a popular pastime at Tar Hollow. The picnic areas offer excellent scenery and a peaceful setting. Six shelters can be reserved through the park office, while the others are available on a first-come, first-served basis.
Pine Lake is a small body of water affording electric motors only. The 15 acres of water surface are perfect for canoeing. Anglers are limited to only two species of fish, bluegill and pan fish. A small launch ramp is located near the 500-foot swimming beach.
Excellent hunting opportunities exist for squirrel, deer, grouse and turkey in the adjacent state forest. A valid Ohio hunting and fishing license is required.
Recreation - Recreations abound at Tar Hollow State Park including activities such as fishing, hiking, horseback riding, mountain biking, backpacking, miniature golf, picnicking, group and family camping, lake swimming, nature study, and limited boating.
Climate - This state has four distinct seasons and a brilliant fall foliage display in it southern woods during mid October. Winter lasts from December through February with average temperatures near 25 degrees F. Low temperatures dip to single digits, but do not often drop below zero. Northern regions of the state receive average snowfall amounts of 55 inches, while the central and southern regions of the state receive lesser amounts with averages near 30 inches. This difference is caused by lake-affect moisture patterns.
Spring temperatures begin to warm the landscapes of Ohio by mid March and are in full swing by April. Temperatures range from 40 through 70 degrees F through the spring months. This season often brings the most rainfall, before the drying heat of summer. Summer can be extremely hot and humid in the interior of Ohio. Temperatures reach above 90 degrees F frequently through July and August. Cooler fall temperatures don't reach the region until mid to late September. This is a pleasant time to visit as the air is crisp with low humidity levels. Ohio's annual precipitation usually reaches slightly above 50 inches.
The park is located in southeastern Ohio several miles east of Chillicothe off State Route 327.
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Science Fair Project Encyclopedia
Religious conversion is the adoption of new religious beliefs that differ from the convert's previous beliefs; in some cultures (e.g. Judaism) conversion also signifies joining an ethnic group as well as adopting that group's religious beliefs. Conversion requires internalization of the new belief system.
A person who has undergone conversion is called a convert or proselyte. A proselyte (from the Latin word proselytus which in turn comes from the Greek word πϱοσήλυτος, proselytos meaning "someone who has found his/her place") is in general a title given to a person who has fully embraced a certain religion, world view, ideology, metaphysics, ontology et cetera. In the traditional sense like in Proselytism this word signified people who have converted to Judaism, but is nowadays used in a wider meaning.
Conversion to Judaism
See also the main article ger tzedek
Jewish law has strict guidelines for accepting new converts to Judaism (a process called "giur"). According to Jewish law, which is still followed as normative by Orthodox Judaism and most of Conservative Judaism, potential converts must want to convert to Judaism for its own sake, and for no ulterior motives. A male convert needs to undergo a ritual circumcision, and there has to be a commitment to observe the 613 commandments and Jewish law. A convert must accept Jewish principles of faith, and reject the previous theology that he or she had prior to the conversion. Ritual immersion in a small pool of water known as a mikvah is required, and the convert takes a new Jewish name and is considered to be a son or daughter (in spirit) of the biblical patriarch Abraham, and a male is called up in that way to the Torah.
The Reform Judaism and Conservative Judaism movements are lenient in their acceptance of converts. Many of their members are married to non-Jews, and these movements make an effort to welcome the spouses of Jews who seek to convert. This issue is a lightning rod in modern day Israel as many immigrants from the former Soviet Union are technically not Jewish.
Conversion to Judaism in history
- See the main article: List of converts to Judaism
The most famous Jewish King, King David, was descended from the convert Ruth (who, according to the Talmud and Midrash, was a Moabite princess). No formal conversion procedure is given in the text; modern critical historians generally hold giur, in its modern sense, to be an innovation of a later period. Joseph, the father of the most famous sage of the Talmud, Rabbi Akiva, was a convert.
Christians were forbidden to convert to Judaism on pain of death during most of the Middle Ages. In the 1700s a famous convert by the name of Count Valentin Potoski in Poland was burned at the stake. He was a contemporary and a disciple of Rabbi Elijah, known as the Vilna Gaon.
In Hellenistic and Roman times, some Pharisees were eager proselytizers, and had at least some success throughout the empire. Some Jews are also descended from converts to Judaism outside the Mediterranean world. It is known that some Khazars, Edomites, and Ethiopians, as well as many Arabs, particularly in Yemen before, converted to Judaism in the past; today in the United States, Israel and Europe some people still convert to Judaism. In fact, there is a greater tradition of conversion to Judaism than many people realize. The word "proselyte" originally meant a Greek who had converted to Judaism. As late as the 6th century the Eastern Roman empire (i.e., the Byzantine empire) was issuing decrees against conversion to Judaism, implying that conversion to Judaism was still occurring.
Relationship with converts
The Hebrew Bible states that converts deserve special attention (Deuteronomy 10:19). The Hebrew word for "convert", ger, is the same as that for a stranger. It is also related to the root gar - "to dwell'. Hence since the Children of Israel were "strangers" - geirim in Egypt, they are therefore instructed to be welcoming to those who seek to convert and dwell amongst them.
Since around 300 CE, Judaism has stopped encouraging people to join its faith. In fact, in Orthodox and Conservative Judaism, converts are often discouraged from becoming Jews and warned that being a Jew entails special obligations, as well as, at least in certain places, the risk of anti-semitism. A Rabbinic tradition holds that a prospective convert should be refused three times.
Differences between Jewish and Christian views
Judaism does not characterize itself as a religion (although one can speak of the Jewish religion and religious Jews). The subject of the Tanach (Hebrew Bible) is the history of the Children of Israel (also called Hebrews), especially in terms of their relationship with God. Thus, Judaism has also been characterized as a culture or as a civilization. Rabbi Mordecai Kaplan defines Judaism as an evolving religious civilization. One crucial sign of this is that one need not believe, or even do, anything to be Jewish; the Rabbinic definition of 'Jewishness' requires only that one be born of a Jewish mother, or that one convert to Judaism in accord with Jewish law. (Today, Reform and Reconstructionist Jews also include those born of Jewish fathers and Gentile mothers if they are raised as Jews.)
To Jews, Jewish peoplehood is closely tied to their relationship with God, and thus has a strong theological component. This relationship is encapsulated in the notion that Jews are a chosen people. Although some have taken this as a sign of arrogance or exclusivity, there are Jewish scholars and theologians who have emphasized that a special relationship between Jews and God does not in any way preclude other nations having their own relationship with God. For Jews, being "chosen" fundamentally means that Jews have chosen to obey a certain set of laws (see Torah and halakha) as an expression of their covenant with God. Jews hold that other nations and peoples are not required or expected to obey these laws, and face no penalty for not obeying them. Thus, as a national religion, Judaism has no problem with the notion that others have their own paths to God (or "salvation"), though it still makes claim as to the truth or falsehood of other beliefs, and as to whether Gentiles are allowed to hold them. Thus, for example, Maimonides believed that the truth claims of Islam were largely false, but he also believed that Gentiles were not sinning by following Islam; on the other hand, he regarded idolatry not just as false, but also as a serious sin, for Jew or non-Jew. In this respect, Rabbinical sources have usually classed Christianity with Islam, rather than with idolatry, though the use of icons in many denominations has raised questions as to whether they are, in fact, idolatrous.
Christianity is characterized by its claim to universality, which marks a break with Jewish identity. As a religion claiming universality, Christianity has had to define itself in relation with religions that make radically different claims about Gods. Christians believe that Christianity represents the fulfillment of God's promise to Abraham and the nation of Israel, that Israel would be a blessing to all nations.
This crucial difference between the two religions has other implications. For example, conversion to Judaism is more like a form of adoption (i.e. becoming a member of the nation, in part by metaphorically becoming a child of Abraham), whereas conversion to Christianity is explicitly a declaration of faith. Of course, conversion to Judaism also entails a declaration of faith, and, in Christian churches, conversion also has a social component, as the individual is in many ways adopted into the Church, with a strong family model.
Conversion to Christianity
In the times of Jesus, all of his disciples were Jews. On occasion, he performed miracles for Gentiles without requiring their conversion; in one conversation with a Samaritan woman, he downplayed the differences between Jews and Samaritans (John 4). Gentiles who sought to join the early Church were often required to undergo conversion to Judaism first including circumcision for men. This requirement was later dropped entirely after Paul forced the issue.
The origin of Christian Baptism in water is derived from the Jewish law requiring a convert to submerge themselves in pure water (of a mikvah) in order to receive a new pure soul from God. It was only many years after Jesus, that there was split in the movement and those seeking to convert to Christianity were not faced with the major obstacles that Judaism presented.
Christianity and Islam are two religions that encourage preaching their faith in order to convert non-believers. In both cases, this missionary property has been used as an excuse for religious wars (crusades) on other countries. This property encourages evangelists to convert people of other faiths, though unfortunately on some occasions by questionable means.
In the year 1000, the Viking age parliament of Iceland decided that the entire country should convert to Christianity, and that sacrifice to the old gods, while still allowed, should no longer be made in the open. Similar mass conversions in other Scandinavian countries were not as democratic.
The Christian denomination of the Religious Society of Friends (Quakers) accepts new members into its monthly meetings. After a person becomes familiar with the beliefs and practices of Friends, he may embrace these things for himself. This embracing of the beliefs and practices of Friends is called convincement. He then applies for membership, and, if accepted is officially a Friend.
Conversion to Islam
One becomes a Muslim by believing that Allah (Arabic for God) is the only god and that Muhammad was His messenger. A person is considered a Muslim from the moment he sincerely makes this witness, the shahada. Of course a new Muslim has to familiarize himself/herself with the religion, the belief, and the practices of Islam, but there is no formal requirement for that. It is a personal process; acceptance of all of that is taken to follow from the original statement, since all of Islam is considered to derive from either divine inspiration, in the form of the Qur'an, or prophetic example, in the form of the hadith and sunna of Muhammad.
Conversion to religions of Indic origin
Religions of Indic origin such as Hinduism, Sikhism and Buddhism do not believe in conversion as a form of religious expansion, even though they welcome anybody to join their faiths. The reason for this is the strongly held belief in these religions that "all religions are true and are only different paths to the same truth". The followers also believe that the religion you follow is to be chosen based on an individual's temprement, birth etc. Also, what would be very strange and foreign to non-indic origin faiths is that people can claim to be follower of multiple religions. For example in Japan which was influenced by the indic faith of Buddhism, it is easy to find people who follow both Buddhism and Shinto. It is also common to find people in India claming to be both Hindu and Buddhist or Hindu and Sikh etc. This inclusivism is in direct contrast to the belief that the ordained path in the book is the only true paths, found in exclusivistic belief systems. This inclusivism also makes any conversion unnecessary. It should be noted that the above does not apply for some sects of Indic faiths, like Soka Gakkai and Hare Krishna/ISKCON.
Conversion to new religious movements and cults
Conversion to new religious movements (NRM's) is riddled with controversies. The anti-cult movement sometimes uses the term thought reform or even brainwashing, though the latter term has now become discredited, for this process. Often they will call certain NRM's cults. However, the definition of a cult has become so broad that in many instances it is almost meaningless and is used to define anything outside of Orthodoxy. NRMs are very diverse and it is not clear whether conversion to NRMs differs from conversion to mainstream religions. See also Brainwashing controversy in new religious movements
Research, both in the USA and in the Netherlands has shown that there is a positive correlation between the lack of involvement in main stream churches in certain areas and provinces and the percentage of people who are a member of a new religious movement. This applies also for the presence of New Age centers. , The Dutch research included Jehovah's Witnesses and the Latter Day Saint movement/Mormonism to the NRM's.
Professor Eileen Barker believes that the psychological changes as described in converts of the Divine Light Mission can be generalized for other NRMs, however she has supplied no proof of such claims.
Conversion of Catholics to Protestantism
Prohibition of conversion
Several ethnic religions don't accept converts, like the Yazidis and the Druze. The only way to become a Yazidi is to be born in a Yazidi family. Conversely, the Shakers and some Indian eunuch brotherhoods don't allow procreation, so every member is a convert.
The English language word proselytism is derived ultimately from the Greek language prefix 'pros' (towards) and the verb 'erchomai' (to come). It generally describes attempts to convert a person from one point of view to another, usually in a religious context.
In the Bible, the word proselyte denotes a person who has converted to Judaism, without overtly negative overtones. In our day, however, the connotations of the word proselytism are almost exclusively negative. Nonetheless, many people use the words interchangeably. An Orthodox writer, Stephen Methodius Hayes has written: "If people talk about the need for evangelism, they meet with the response, "The Orthodox church does not 'proselytize' as if evangelizing and proselytism were the same thing."
Many Christians consider it their obligation to follow what is often termed the "Great Commission" of Jesus, recorded in the final verses of the Gospel of Matthew: "Go to all the nations and make disciples. Baptize them and teach them my commands." The early Christians were noted for their evangelizing work.
The difference between the two terms is not easily defined. What one person considers legitimate evangelizing, or witness bearing, another may consider intrusive and improper.
Illustrating the problems that can arise from such subjective viewpoints is this extract from an article by Dr. C. Davis, published in Cleveland State University's 'Journal of Law and Health': "According to the Union of American Hebrew Congregations, Jews for Jesus and Hebrew Christians constitute two of the most dangerous cults, and its members are appropriate candidates for deprogramming. Anti-cult evangelicals ... protest that 'aggressiveness and proselytizing . . . are basic to authentic Christianity,' and that Jews for Jesus and Campus Crusade for Christ are not to be labeled as cults. Furthermore, certain Hassidic groups who physically attacked a meeting of the Hebrew Christian 'cult' have themselves been labeled a 'cult' and equated with the followers of Reverend Moon, by none other than the President of the Central Conference of American Rabbis".
Views on the propriety of proselytism, or even evangelism, differ radically. Some feel that freedom of speech should have no limits and that virtually anyone, anywhere should have the right to talk about anything they see fit. Others see all sorts of evangelism as a nuisance and an intrusion and would like to see them proscribed. Thus, Natan Lerner observes that the issue is one of a clash of rights - the right of a person to express his views versus the right of a person not to be exposed to views that he does not wish to hear.
From a legal standpoint, there do appear to be certain criteria in distinguishing legitimate evangelization from illicit proselytism:
- All humans have the right to have religious beliefs, and to change these beliefs, even repeatedly, if they so wish. (Freedom of Religion)
- They have the right to form religious organizations for the purpose of worship, as well as for promoting their cause (Freedom of Association)
- They have the right to speak to others about their convictions, with the purpose of influencing the others. (Freedom of Speech).
By the same token, these very rights exercise a limiting influence on the freedoms of others. For instance, the right to have one's religious beliefs presumably includes the right not to be coerced into changing these beliefs by threats, discrimination, or similar inducements.
Hence a category of improper proselytizing can be discerned.
- It would not be proper to use coercion, threats, the weight of authority of the educational system, access to health care or similar facilities in order to induce people to change their religion.
- It would be improper to try to impose one's beliefs on a 'captive audience,' where the listeners have no choice but to be present. This would presumably require restraint in the exercise of their right to free speech, by teachers in the classroom, army officers to their inferiors, prison officers in prison, medical staff in hospitals, so as to avoid impinging on the rights of others.
- It would not be proper to offer money, work, housing or other material inducements as a means of persuading people to adopt another religion.
Issues involving proselytism
Since the collapse of the former Soviet Union and the rise of democracy in the Eastern Bloc, the Russian Orthodox Church has enjoyed a revival. However, it takes exception to what it considers illegitimate proselytizing by the Roman Catholic Church, the Salvation Army, Jehovah's Witnesses and other religious movements in what it refers to as its canonical territory.
Greece has a long history of conflict, mostly with Jehovah's Witnesses but also with some Pentecostals over its laws on proselytism. This situation stems from a law passed in the 1930s by the dictator Ioannis Metaxas. A Jehovah's Witness, Minos Kokkinakis, won the equivalent of US $14,400 in damages from the Greek state after being arrested repeatedly for the 'offence' of preaching his faith from door to door. In another case, Larissis vs. Greece, a member of the Pentecostal church also won a case in the European Court of Human Rights.
- 1. Schepens, T. (Dutch) Religieuze bewegingen in Nederland volume 29, Sekten Ontkerkelijking en religieuze vitaliteit: nieuwe religieuze bewegingen en New Age-centra in Nederland (1994) VU uitgeverij ISBN 90-5383-341-2
- 2. Starks, R & W.S. Bainbridge The future of religion: secularization, revival and cult formation (1985) Berkely/Los Angeles/London: University of California press
- 3. Barrett, D. V. The New Believers - A survey of sects, cults and alternative religions (2001) UK, Cassell & Co
- "Proselytism, Change of Religion, and International Human Rights", by Natan Lerner, PhD (legal aspects of defining illicit proselytism)
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details
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The Billhead evolved from what was known as a "Trade Card," and in the twentieth Century, became known as letterhead. It was created by printing a heading at the top of a sheet of paper, usually from an engraved copper plate. The lower part of the sheet was used for writing a list, a note, or a bill. The standard billhead measured seven to eight inches wide, and four inches or more in length, depending on the need for space for writing the bill. The printed heading usually included an illustration, and sometimes a street address or location of the business. They also included space to write the date and town where the business transaction took place. They were printed on durable rag paper up until the 1860's and 1870's, after which they were printed on thinner woodpulp paper. In general, billheads of this style were in use and remained relatively the same for approximately a 150 year time frame, over three centuries. As historical artifacts, billheads are useful for providing information about tradesmen's products and prices. They help document the types of goods and services that consumers were purchasing.
The American Antiquarian Society has a collection of over 500 billheads representative of what was printed between the 1780's and 1900. They are housed in two boxes. The first box is devoted entirely to billheads from Boston merchants. The other box includes billheads from traders and hotels located in several states, including Massachusetts. They are organized alphabetically by city and state.
-Terri Tremblay, Assistant Curator of Graphic Arts
Source: Rickards, Maurice, The Encyclopedia of Ephemera. New York: Routledge, 2000.
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This advice is suitable for open-grown ornamental trees. Although pruning does make trees slightly smaller than they would be without pruning, attempting to keep a big tree small by pruning is usually unsuccessful. This advice does not apply to restricted tree forms such as fans and espaliers.
When to prune trees
Deciduous trees (ones that lose their leaves in winter) are usually pruned in autumn and winter. In some cases, for example with magnolias and walnuts, pruning is best done in late summer, as healing is quicker.
Trees such as Prunus sp, which are prone to silver leaf disease are best pruned from April to July when the disease spores are not on the wind, and the tree sap is rising rather than falling (which pushes out infection rather than drawing it in).
Some trees can bleed sap if pruned in late winter and early spring. Although seldom fatal, this is unsightly and can weaken the tree. Birches and walnuts often bleed if pruned at the wrong time.
Evergreens seldom need pruning, although dead and diseased branches can be removed in late summer.
How to prune trees
Prior to undertaking any work, it is essential to ascertain if a Tree Preservation Order (TPO) is in place or if the tree is in a Conservation Area. If either is the case, seek permission from your local council before beginning work. Potentially dangerous limbs can, in theory, be removed without permission but the penalties for breaching the legislations, inadvertently or not, can be severe.
Safety is of prime importance when working with trees, so make an honest appraisal of your capabilities, assess the area in which any branches may fall and erect warning signs or barricades if necessary before beginning. If in any doubt engage a professionally qualified tree surgeon or aboriculturist.
Take a step back and decide what needs to be done to produce a balanced, attractive tree. Work with the natural habit of the tree to shorten or remove branches. Going against the tree’s natural habit produces ungainly trees that lack grace.
Always start by removing damaged, dead, diseased shoots, followed by weak, lax or rubbing growth.
How to remove tree branches and limbs
- Wear protective gloves and, if necessary, eye and head protection
- When cutting a stem, cut just above a healthy bud, pair of buds or side shoot. Where possible, cut to an outward facing bud or branch to avoid congestion and rubbing of branches
- Make your cut 0.5cm (¼in) above the bud. Beware cutting too close, as this can induce death of the bud Beware cutting too far from the bud, as this can result in dieback of the stub and entry of rots and other infections
- When removing larger limbs, make an undercut first about 20-30cm (8in-1ft) from the trunk, and follow this with an overcut. This will prevent the bark tearing, leaving a clean stub when the branch is severed
- Then remove the stub, first making a small undercut just outside the branch collar (the slight swelling where the branch joins the trunk), followed by an overcut to meet the undercut, angling the cut away from the trunk to produce a slope that sheds rain
- Avoid cutting flush to the trunk as the collar is the tree’s natural protective zone where healing takes place
- There is no need to use wound paints, as they are not thought to contribute to healing or prevent disease. The exception is plums and cherries (Prunus sp), where wound paint may be used to exclude silver leaf disease spores
If pruning cuts bleed sap, don’t bandage or bind the cut, as attempts to stem the bleeding are likely to be unsuccessful and may impede rather than aid healing.
Remove branches of more than 2cm (½in) in diameter with a sharp pruning saw. Don't make a flush cut - come out just slightly so that it heals naturally.
Small branches can easily be removed with secateurs.
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While the Right to Education Act (RTE) mandates that every child has the fundamental right to free and compulsory elementary education in India, how do you ensure education for children in difficult circumstances? Malini Sen finds out
From West Bengal and Jharkhand, Chhattisgarh to Orissa, the Maoist-dominated regions are making the headlines. But, in the sidelines of the news is another story - education for children in difficult circumstances, which requires special attention. Apart from political strife, difficult circumstances indicate internal displacement, natural disasters, communal and other forms of violence.
While the Right to Education Act (RTE) mandates that every child has the fundamental right to free and compulsory elementary education in India, how do you set up formal schools in these vulnerable regions? How do you convey the importance of education, when life itself is uncertain?
During a visit to Dantewada (Chhattisgarh) and Khammam ( Andhra Pradesh) a few years ago, the National Commission for Protection of Child Rights (NCPCR) had strongly urged that schools be identified as 'zones of peace.' This would include nonuse of schools for any other than educational purposes, separation of schools from the camps, and introduction of programmes addressing the psycho-social needs of the children delivered within the school environment with appropriate training of teachers.
Shantha Sinha, chairperson, NCPCR, asserts that education should not be compromised at any cost. "In regions of conflict, children are more prone to trafficking, joining the labour force or even the armed conflict. The only way to make sure that they are safe is to keep them in school. And now, with RTE, it is their fundamental right," she adds. The NCPCR is working towards reviving schools in districts facing civil unrest, where there has been a total breakdown of the education system.
According to Unicef sources, at present, there are around 33 districts that are affected by naxal violence. Access to education has been significantly affected, staff enjoy little mobility, teacher attendance is low, civil work has come to a standstill, several school buildings have been destroyed and a number of schools are being used by the forces.
In Chhattisgarh, Unicef has been working with the local administration in South Bastar to bring children back to residential school facilities in Porta Cabins (prefabricated bamboo structures) and provide them with a child-friendly environment.
At the initial phase, the methodology should be more about direct delivery, says Bhagyashri Dengle, executive director, Plan India. "For example, setting up of child-care centres for children aged 0-6 years, special training centres for children in the age group of 10-18, supplying teaching-learning materials such as text books, etc."
Secondly, trained facilitators should be engaged to provide psycho-social support to the children affected by emergencies. The primary aim is to provide care and support to the children at regular intervals. "Our role should be of a facilitator, building the right linkages with schools so that children can go back to school safely," adds Dengle.
Reiterating the importance of psycho-social support, Venkatesh Malur, education specialist, Unicef, says sports for development and arts-based therapy has been undertaken to engage children in various participatory activities and divert their attention from what is happening around them in Chhattisgarh.
"Avenues for expression and articulation of their thoughts and ideas have been created using which children have been able to exhibit their skills," he adds. Innovative measures such as activity-based learning methodologies are being used in the classroom. Teachers have been trained on the methodology and age-appropriate learning materials have been designed.
Education also has a vital role to play in social reconstruction in the aftermath of a disaster. In Gujarat, after the earthquake (2001), the concept of building as a learning aid (BaLA) was developed in some schools. "The rebuilding of schools and resuming classes is a positive step towards recovery and the future. It is essential to review the development of new curricula and training of teachers in these areas, this could begin to symbolise a departure from the violent past and the advance towards a peaceful future," says Geeta Menon, who is working as a consultant with Unicef on education in emergencies.
The Druk White Lotus School in Leh, which became famous after it featured in the Bollywood film 3 Idiots, was devastated in a cloudburst in 2010. Several rooms including the computer lab and elementary classes block was damaged in the disaster. Thanks to the concerted efforts of both the local and school authorities, the school got a new lease of life.
Education is essential both as a human right and as a component of the peace-building process. "Displacement is a crucial time of transition and vulnerability not just for children, but for youth and adults as well. Failure to incorporate youth and adult education and vocational training as a standard component during displacement is a detrimental omission in the quest to secure peace and initiate long-term development," says Malur.
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History of Initiative & Referendum in Arizona
|Laws • History|
|List of measures|
The History of Initiative & Referendum in Arizona began when acquired statewide initiative, referendum, and recall rights at the time of statehood in 1912. The first initiative in the state was for women's suffrage. It was a landslide victory, passing by a margin of greater than two to one on Nov. 5, 1912.
Then, in 1914, Arizona saw of 15 qualified initiatives, which held the record until 2006 when 19 initiatives were passed. Four of the 1914 initiatives passed because of the efforts of organized labor. One prohibited blacklisting of union members; a second established an "old age and mothers' pension"; another established a state government contract system, and a fourth limited businesses employment of non-citizens. Lastly, the voters in 1914 passed an initiative that barred the governor and legislature from amending or repealing initiatives.
In response, the legislature tried to pass a constitutional amendment that would make it more difficult to pass initiatives. Because this amendment needed the approval of voters, the Arizona Federation of Labor waged a campaign against the measure. The amendment was narrowly defeated in 1916.
- This chart includes all ballot measures to appear on the Arizona ballot in the year indicated, not just initiated measures. See also Arizona ballot measures.
|Year||Propositions on ballot||How many were approved?||How many were defeated?|
Arizonans owe many of their reforms to John Kromko. Kromko, like most Arizonans, is not a native; he was born near Erie, Pennsylvania, in 1940 and moved to Tucson in the mid-1960s. He was active in protests against the Vietnam War, and in the 1970s and 1980s he was elected to the lower house of the state legislature several times. By night, he was a computer-programming instructor; by day, he was Arizona’s "Mr. Initiative."
Kromko’s first petition was a referendum drive to stop a Tucson city council ordinance banning topless dancing, arguing for free speech. In 1976 Kromko was among the handful of Arizonans who, in cooperation with the People’s Lobby Western Bloc campaign, succeeded in putting on the state ballot an initiative to phase out nuclear power. The initiative lost at the polls, but Kromko’s leadership on the issue got him elected to his first term in the legislature.
Repealing the sales tax on food
Once elected, Kromko set his sights on abolishing the sales tax on food, a "regressive" tax that hits the poor hardest. Unsuccessful in the legislature, Kromko launched a statewide initiative petition and got enough signatures to put food tax repeal on the ballot. The legislature, faced with the initiative, acted to repeal the tax.
After the food tax victory, Kromko turned to voter registration reform. Again the legislature was unresponsive, so he launched an initiative petition. He narrowly missed getting enough signatures in 1980, and he failed to win re-election that year.
Undaunted, he revived the voter registration campaign and turned to yet another cause: Medicaid funding. Arizona in 1981 was the only state without Medicaid, since the legislature had refused to appropriate money for the state's share of this federal program.
In 1982, with an initiative petition drive under way and headed for success, the legislature got the message and established a Medicaid program. Kromko and his allies on this issue, the state’s churches, were satisfied and dropped their petition drive.
Motor Voter initiative
The voter registration initiative, now under the leadership of Les Miller, a Phoenix attorney, and the state Democratic Party, gained ballot placement and voter approval. In the ensuing four years, this "Motor Voter" initiative increased by over 10 percent the proportion of Arizona’s eligible population who were registered to vote.
Late legislative career
Kromko, re-elected to the legislature in 1982, took up his petitions again in 1983 to prevent construction of a freeway in Tucson that would have smashed through several residential neighborhoods. The initiative was merely to make freeway plans subject to voter approval, but Tucson officials, seeing the campaign as the death knell for their freeway plans, blocked its placement on the ballot through various legal technicalities. Kromko and neighborhood activists fighting to save their homes refused to admit defeat. They began a new petition drive in 1984, qualified their measure for the ballot, and won voter approval for it in November 1985.
Arizona’s moneyed interests poured funds into a campaign to unseat Kromko in 1986. Kromko not only survived but also fought back by supporting a statewide initiative to limit campaign contributions, sponsored by his colleague in the legislature, Democratic State Representative Reid Ewing of Tucson. Voters passed the measure by a two to one margin.
Kromko’s initiative exploits have made him the most effective Democratic political figure, besides former governor Bruce Babbitt, in this perennially Republican-dominated state. And Babbitt owes partial credit for one of his biggest successes - enactment of restrictions on the toxic chemical pollution of drinking water - to Kromko. Early in 1986 Kromko helped organize an environmentalist petition drive for an anti-toxic initiative, while Babbitt negotiated with the legislature for passage of a similar bill. When initiative backers had enough signatures to put their measure on the ballot, the legislature bowed to the pressure and passed Babbitt's bill. Even today, Kromko is still active in politics, writing letters to the editor about immigration policies.
Petition drive problems in 2008
2008 was a tough year for ballot initiatives in Arizona. Nine citizen initiatives filed signatures to qualify for the November 2008 Arizona ballot by the state's July 3 petition drive deadline. In the end, only six of the initiatives were certified, with three initiatives disqualified as a result of an historically high number of problems with flawed petition signatures. When the November vote was held, of the six that qualified for the ballot, only one was approved.,
Criticisms of process
After 19 were proposed in 2006, legislators were worried about "ballot fatigue" or overuse of the initiative system. This led to legislators considering steps to limit or otherwise exert more control over the initiative process. Ironically, any attempt to alter the initiative and referendum process would require an amendment to the state constitution, and thus in itself be put forth as a referendum.
This article is significantly based on an article published by the Initiative & Referendum Institute, and is used with their permission. Their article, in turn, relies on research in David Schmidt's book, Citizen Lawmakers: The Ballot Initiative Revolution.
Also portions of this article were taken from Wikipedia, the free encyclopedia under the GNU license.
- ↑ Arizona Daily Star, "'Clown' takes some serious initiative", July 20, 2007
- ↑ Arizona Republic, "'Flawed' election petitions face review", September 13, 2008
- ↑ Phoenix New Times, "Citizen initiatives have been kicked off the ballot this year in record numbers, and the problems could go much deeper than invalid signatures", August 21, 2008
- ↑ Legislators seeking more control over initiatives, Arizona Republic, Feb. 13, 2007
- ↑ History of Arizona's initiative
- ↑ Citizen Lawmakers: The Ballot Initiative Revolution Temple University Press, 352 pp., ISBN-10: 0877229031, October 1991
History of I&R
Alaska · Arizona · Arkansas · California · Colorado · Florida · Idaho · Illinois · Kentucky · Maine · Maryland · Massachusetts · Michigan · Mississippi · Missouri · Montana · Nebraska · Nevada · New Mexico · North Dakota · Ohio · Oklahoma · Oregon · South Dakota · Utah · Washington · Wyoming
Direct Legislation by the Citizenship Through the Initiative and Referendum · Citizen Lawmakers: The Ballot Initiative Revolution · Direct Legislation: Voting on Ballot Propositions in the United States
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BBSRC is not responsible for the content of external websites
Biology by design – how synthetic biology could revolutionise everything from medicines to energy
13 July 2012
In a series of articles we will be highlighting the work of some of the leading synthetic biology researchers in the UK. Here we profile Professor Dek Woolfson of the University of Bristol, Professor Jamie Davies of the University of Edinburgh and Professor Richard Cogdell of the University of Glasgow.
Flat pack proteins – Professor Dek Woolfson, University of Bristol
Professor Dek Woolfson is hoping to use synthetic biology to create new structures out of proteins with uses ranging from wound repair to water purification.
- Proteins play many important roles in nature.
- Proteins can assemble into complicated structures like tiny pumps and motors.
- Scientists are hoping to combine proteins in new ways using synthetic biology to create useful new tools for uses as diverse as water filtration and medicine.
Proteins are like nature's robots working tirelessly in the cells of every plant, animal and microbe to do virtually all of the important functions that make life tick. Each individual protein can twist and fold into an incredibly complex 3D shape, with holes, cracks and protrudances giving it its function. Groups of proteins then combine with one another and other types of molecules to create bigger and more complicated structures still. Understanding how proteins assemble and combine is at the heart of Professor Dek Woolfson's research at the University of Bristol.
Professor Dek Woolfson
This work is important for our understanding of biology because by figuring out how to make parts these molecular machines from scratch scientists can get a much better understanding of how they work in nature. It could also have a range of possible applications.
Professor Woolfson and his team are working on a toolkit of newly designed proteins that could be used as building blocks to produce biological machines. This is a key pillar of a synthetic biology approach. Scientists like Professor Woolfson hope to create catalogues of modular parts so that biological structures can be built from flat pack rather than being crafted from scratch each time.
One such structure that Professor Woolfson's team are working on is a synthetic version of the extracellular matrix, the scaffold that surrounds our cells.
A synthetic extracellular matrix could be used in regenerative medicine to help generate tissues like skin, nerves or bone in the test tube that could then be transplanted into patients. Professor Woolfson is currently working with clinical scientists exploring applications for the technology in wound repair.
Another project in their lab is attempting to use rational protein design to produce new technologies for water purification and desalination. The team have discovered a new cylindrical protein structure which they call CC-Hex which they think could be engineered into biological membranes to filter water. These devices would be particularly valuable for producing small scale products that could be used easily by people who do not have access to clean water in the developing world.
This research is being developed in collaboration with the University of Oxford and with an Australian water consortium that brings together a team of engineers, biochemists, chemists, materials scientist and microbiologists.
Prof Woolfson explains "When we discovered CC-Hex we thought we might use it to make enzymes. It was a visiting colleague from Australia who recognised the similarity of the structure to aquaporins (a natural protein that rescues water in kidneys, the brain and even the roots of plants). He suggested that we explore that direction too and it is now the basis of our latest BBSRC grant. We are far from achieving a working prototype but are collaborating with Australian scientists with this goal in mind."
Designer tissues – Professor Jamie Davies, University of Edinburgh
Stem cells offer incredible medical promise because they can turn into virtually any tissue in our bodies; but what about tissues that do not exist in our bodies or even in nature?
- During development, a simple group of cells multiplies and rearranges to form complicated tissues and organs and eventually a whole plant or animal.
- Currently, scientists are working to coax stem cells to produce human tissues in the lab to repair damaged organs.
- Using synthetic biology, scientists could put new programming in to cells so that they develop into never-before seen types of tissues with a range of medical uses.
Professor Jamie Davies of the University of Edinburgh is working to use synthetic biology to control cell and tissue shape, research which he calls 'synthetic morphology'. His work could lead to a future where cells can be programmed to self assemble into new structures and tissues which have never existed before in nature.
Professor Jamie Davies
This science is in its infancy and there are a number of technical hurdles still to be overcome. However it promises to give us a far greater understanding of how organisms develop which might give scientists insights that could help prevent developmental abnormalities like conjoined twinning.
As well as increasing our understanding of development this work could allow the production of useful new tissues that would not be possible with stem cells. You could imagine, for example, that tissues grown in this way could provide an interface to allow a person to control movement in an artificial hand or even to see through an artificial eye.
These developments are still some way off. However in the nearer term Professor Davies hopes to be able to improve medical technologies like dialysis machines by developing tissues that can live happily inside medical machinery. Dialysis machines are very good at replicating the mechanical functions of a kidney but they cannot perform the biochemical functions that are important in properly filtering blood. By designing tissues that could grow along the tubes of a dialysis machine researchers could produce a more effective artificial kidney.
Professor Davies explains "The development of even really complex tissues can be broken down into a series of simple events like the multiplication, clumping together or movement of cells. There are about ten of these simple behaviours and we think that by programming cell circuitry to carry them out in different orders we can coax cells into new types of tissues in ways that we can predict."
The immediate value of this work to scientists is that it will give them a much deeper understanding of the process of development. How relatively unorganised populations of cells assemble precisely into something as complex as a person is one of the big outstanding questions in biology. By developing synthetic systems that cause cells to organise and assemble themselves, the researchers can begin to understand how it happens in nature.
One of the immediate challenges that Professor Davies and their team faced when starting this work was that they wanted to work with animal cells. Most synthetic biology to date has been in simple organisms that are easy to work with like bacteria or yeast. Mammalian cells are much bigger and more complex than those of bacteria which make them considerably harder to work with.
However this work is not just limited to human or animal cells. It should be possible to programme bacteria, yeast or plant cells to form new multicellular structures which could have an enormous range of uses in medicine and industry.
The artificial 'leaf' – Professor Richard Cogdell, University of Glasgow
Professor Richard Cogdell is hoping to use synthetic biology to create an artificial "leaf" capable of converting the sun's energy into sustainable liquid fuels.
- Plants use photosynthetisis to capture energy of the sun to create fuel to power the plant's growth.
- We use this fuel ourselves in the form of wood, coal, oil and gas.
- By using the tools of synthetics biology, scientists hope to create an artificial system that can do photosynthesis,
- This could capture the sun's energy like a solar panel but would produce liquid fuel rather than electricity.
We have always relied on plants to provide us with energy. For millennia, burning wood was humanity's main, sometimes only, source of power. Later, more energy dense fuels – coal, oil and gas, drove the development of modern society.
Professor Richard Cogdell
By burning these fuels we are tapping into the stored energy of the sun. In the case of wood this might have been captured months or years before. When we burn fossil fuels we are releasing energy that fell as sunlight on the world of the dinosaurs hundreds of millions of years ago.
Only plants, algae and some bacteria have the amazing ability to capture and store the sun's rays as sugars using photosynthesis. While amazing, photosynthesis is actually quite an inefficient process. A plant is not a machine for producing fuel, rather a machine for producing plants, and as such scientists think that they might be able to tweak photosynthesis to produce fuel more efficiently. The researchers, based at the University of Glasgow, hope to deliver the next stage in our long relationship with photosynthesis by taking it out of the leaf and into the lab.
Professor Cogdell, who is leading the research project, explains: "More energy hits the surface of the Earth in the form of sunlight in the space of one hour than the entire human race uses in a whole year. This abundant energy is given away for free but making use of it is tricky. We can use solar panels to make electricity but it's intermittent and difficult to store. You can't fly an aeroplane or send a ship round the world using batteries, you need a fuel. What we are trying to do is to take the energy from the sun and trap it so that it can be used when it is needed most."
The researchers hope to use a chemical reaction similar to photosynthesis but in an artificial system. Plants take solar energy, concentrate it and use it to split apart water into hydrogen and oxygen. The oxygen is released and the energy from the hydrogen used to lock carbon into a fuel. The latest research aims to use synthetic biology to replicate the process outside of the cell.
Professor Cogdell added: "We are working to devise a chemical system that could replicate photosynthesis artificially on a grand scale. This artificial leaf would use solar collectors and produce a fuel, as opposed to electricity."
Professor Cogdell hopes that his team's artificial system could also improve on natural photosynthesis to make better use of the sun's energy. By stripping back photosynthesis to a level of basic reactions, much higher levels of energy conversion could be possible.
Ultimately, success in this research could allow the development of a sustainable carbon neutral economy arresting the increasing carbon dioxide levels in the atmosphere from fossil fuel burning. In fact, if successful, this research could allow for carbon to be harvested from the atmosphere and returned to the ground, reversing the accumulation of carbon caused by burning fossil fuels.
The research is funded through a joint EU funding scheme "EuroSolarFuels" which aims to produce fuels from light. The BBSRC funds the UK part of this research.
What is synthetic biology?
Synthetic biology is the science of designing, engineering and building useful new biological systems which have not existed before in nature.
Using our ever-increasing understanding of genetics and cell biology synthetic biologists are able to design complicated biological parts, systems and devices to act as sensors, tissues or to produce useful chemicals. These technologies could deliver advances in a wide range of fields including medicine, biofuels and renewable materials.
A synthetic biology approach offers incredible promise but also poses many ethical, legal and even existential questions for the scientific community, policymakers and for all of us to think about. Some of these questions were explored in a public dialogue carried out by BBSRC and the Engineering and Physical Sciences Research Council in 2010.
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An Efficient Solar Harvest
Solar power could be harvested more efficiently and transported over longer distances using tiny molecular circuits based on quantum mechanics, according to research inspired by new insights into natural photosynthesis. Incorporating the latest research into how plants, algae and some bacteria use quantum mechanics to optimize energy production via photosynthesis, UCL scientists have set out how to design molecular circuitry that is 10 times smaller than the thinnest electrical wire in computer processors. Published in Nature Chemistry, the report discusses how tiny molecular energy grids could capture, direct, regulate and amplify raw solar energy.
Solar fuel production is all about energy from light being absorbed by an assembly of molecules; this electronic excitation is subsequently transferred to a suitable acceptor. For example, in photosynthesis, antenna complexes capture sunlight and direct the energy to reaction centers that then carry out the associated chemistry.
In photosynthesis chlorophyll captures sunlight and directs the energy to special proteins that help make oxygen and sugars. This is no different in principle than a solar cell.
In natural systems energy from sunlight is captured by colored molecules called dyes or pigments, but it is only stored for a billionth of a second. This leaves little time to route the energy from pigments to the molecular machinery that produces fuel or electricity.
The key to transferring and storing energy very quickly is to harness the collective quantum properties of antennae, which are made up of just a few tens of pigments.
Recent studies have identified quantum coherence and entanglement between the excited states of different pigments in the light-harvesting stage of photosynthesis. Although this stage of photosynthesis is highly efficient, it remains unclear exactly how or if these quantum effects are relevant.
Dr Alexandra Olaya-Castro, co-author of the paper from UCL’s department of Physics and Astronomy said: “On a bright sunny day, more than 100 million billion red and blue colored photons strike a leaf each second.”
“Under these conditions plants need to be able to both use the energy that is required for growth but also to get rid of excess energy that can be harmful. Transferring energy quickly and in a regulated manner are the two key features of natural light harvesting systems.
“By assuring that all relevant energy scales involved in the process of energy transfer are more or less similar, natural antennae manage to combine quantum and classical phenomena to guarantee efficient and regulated capture, distribution and storage of the sun’s energy.”
Summary of lessons from nature about concentrating and distributing solar power with nanoscopic antennae:
The basic components of the antenna are efficient light absorbing molecules.
Take advantage of the collective properties of light-absorbing molecules by grouping them close together. This will make them exploit quantum mechanical principles so that the antenna can: i) absorb different colors ii) create energy gradients to favour unidirectional transfer and iii) possibly exploit quantum coherence for energy distribution.
Make sure that the relevant energy scales involved in the energy transfer process are more or less resonant. This will guarantee that both classical and quantum transfer mechanisms are combined to create regulated and efficient distribution of energy.
Article by Andy Soos, appearing courtesy Environmental News Network.
|Tags: energy distribution energy production photosynthesis quantum mechanics solar cell solar energy||[ Permalink ]|
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Machines that “Destroy” the Earth (Nov, 1946)
Machines that “Destroy” the Earth
Intricate mechanisms at New York Planetarium show how celestial forces could burn, blast or freeze the world.
By HARRY SAMUELS
THREE times a day in five spectacular ways the earth “dies” in the Hayden Planetarium in New York.
First performed in 1939, the Planetarium’s sky drama was shut down by the war in 1941 and was not resumed until recently. The new “End of the World” show is considerably more vivid than its prewar predecessor because of added startling effects and more authentic background material worked out by the Planetarium technical and scientific staffs. The pictures and captions on the accompanying pages explain how these effects are obtained.
Scientists and others—mostly others-have predicted a possible end to the world in the near future as a result of chain reactions set off by the use of atomic energy.
The varieties of cosmic destruction depicted in the Planetarium show are, however, many millions of years distant by estimates of most astronomers.
The Planetarium audience, seated under a huge dome, is transported through time and space to the center of Central Park in New York on a day billions of years in the future.
The earth comes to its end the first time as the result of the misbehavior of the sun. The sun bursts into a nova, or new star, something that more than 10 other self-illuminated, gigantic heavenly bodies do each year (PSM, July ’46, p. 108). The sudden, cataclysmic flood of heat and energy generated by the blast shrivels the earth to death.
Next, the Planetarium onlookers watch the other, but equally final, extreme—the eventual cooling of the sun to a degree where our globe becomes bleak and frozen and can no longer sustain life.
Gordon A. Atwater, Planetarium chairman, says this cooling of the sun is an almost certain eventuality unless it has some unknown and inexhaustible means of renew-ing its energy.
In the third preview of doom, the earth and all the other planets of our solar system are innocent victims of a celestial hit-and-run accident. The sun explodes as the result of a collision with a star from far out in space.
The fourth possible end of the world occurs when a mysterious wanderer from space, a comet with a flaming tail, appears on the celestial stage. It approaches the earth at bewildering speed. Closer and closer it comes until it strikes with a terrible impact. Where the earth was a fraction of a second before there is now only space. Though not probable, a collision between the earth and a comet is possible.
Astronomers know that some remote day the earth will pull the moon within the so-called “Roche’s limit,” a distance from the earth roughly twice the earth’s diameter. What will happen then is shown in the awesome finale at the Planetarium.
Moving slowly at first, but gaining momentum as it approaches the New York skyline, a huge and terrifying moon soon fills half of the sky. There is a shattering crash as the moon explodes in the southeast horizon, breaking up into thousands of flaming meteors that bombard the mother planet. The skyline that rims the Planetarium becomes a circle of blazing buildings. As the flames die down, pieces of the shattered moon circle the earth similar to the moons of Saturn—a halo for a dead world!
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While typically thought of as three sisters, according to mythology, the real number of them are unknown. Virgil, the classical Roman poet, was first to recognize the three known Furies. Their names are Alecto (which means "unceasing"), Megaera ("grudging"), and Tisiphone ("avenging murder"). They tend to appear as women with serpent wreathes on their heads, blood running from their eyes and the wings of a bat or bird. And occasionally even the body of a dog.
When they're not pursuing wrongdoers on Earth, the Furies are thought to spend most of their time in Tartarus, which is in the underworld below Hades, torturing damned souls.
|'Orestes Pursued by the Furies' (1921) by John Singer Sargent|
- On a rare few occasions, they would be called to punish a god, but mostly, they sought justice on mortals who broke laws such as murdering kin or breaking oaths.
- A common Greek story featuring the Furies is "Eumenides" by Aeschylus. The Furies torment Orestes until he begs the goddess Athena to convince the Furies to leave him alone.
- The Furies are known to be just, so if one repents, they will stop tormenting the person and sometimes bestow upon them blessings.
Good links to check out for more information:
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The study of motion is often called kinematics. We will begin our study with one dimensional kinematics. We will later expand to 2 and 3 dimensional kinematics after we have studied vectors.
We can give the position of an object in relation to a reference point. There are a number of variables we can use for position, such as x, d, or s. The official metric unit for position is the meter (abbreviated m). The meter was first defined in terms of the circumference of the Earth on a meridian passing through Paris. It is now defined in terms of the speed of light. When working with other scales, it might be convenient to use other metric units such as the nanometer (nm), the centimeter (cm), and the kilometer (km).
We will often use exponential notation. Exponential notation is convenient for expressing very large and small numbers.
For instance, 12,300 would be expressed as 1.23 x 10,000 or 1.23 x 104
So 3.14 km = 3140 m = 3.14 x 103 m
For small numbers, 0.000345 = 3.45 x 10-4
A micrometer, 1 μm = 10-6 m The width of a human hair on average is 10 μm. This would be 10 x 10-6 m.
The wavelength of a helium-neon laser is 633 nm = 633 X 10-9 m = 6.33 x 10-7 m
The common metric units are given in powers or 3.
The kilometer is 1000 m.
Although the 100 centimeters = 1 meter it is not actually a common unit.
1 Millimeter = 1mm = 10-3 m
1 Micrometer = 1um = 10-6 m
1 Nanometer = 1nm = 10-9 m
1 Picometer = 1pm = 10-12 m
1 Femotometer = 1fm = 10-15 m also known as a Fermi
Except for kilometer, we often do not use the larger metric prefixes for distance. But they are used for frequencies and other units in physics.
1 Kilometer = 1 km = 1000 m = 103 m
Megameter = 1Mm = 106 m
Gigameter = 1Gm = 109 m
Terrameter = 1 Tm = 1012 m
Common British Imperial units for measuring distance include the inch, the foot, the yard, and the mile. An easy way to remember the conversion from meters to miles can be remembered in terms of Track and Field. The loop in a track is ¼ mile long. It is also known as the 400 m race, so 1 mile is approximately = 1600 m. Engineers in America commonly use Imperial units. Very small measurements for the purposes of manufacturing are given in 1/1000ths of an inch.
When dealing with astronomical distances there are other units we might use such as the light-year, the parsec, or the Astronomical Unit. The light-year is the distance light will travel in one year. An object which is one parsec away has one arc-second of parallax from Earth. An astronomical unit is the average distance from the Earth to the Sun.
Distance vs Displacement
In physics we often study the change in position of an object. If we are only examining the change in position from the start of our observation to the end, we are talking about displacement. We ignore how we get from point A to point B. We are only concerned with how the crow flies. If we are concerned with our path, we are working with distance (see figure A).
For example, let us suppose I were to talk around the perimeter of a square classroom (see figure B). The classroom is 10 meters on a side. At the end of my trip I return to my original starting position. The distance traveled would be 40 m. The displacement would be zero meters because displacement only depends on the starting and ending positions.
The other important distinction between distance and displacement is that distances do not have a direction. If you were wearing a pedometer is would record distance. The odometer on a car records distance. Displacement has a direction and a magnitude. Magnitude is a fancy physics term for size or amount.
For instance, suppose I walked 10 m North, 10 m East, 10 South, and then 5 m West (see figure C). My distance traveled would be 35 m. There is a magnitude but no net direction. Since we can describe distance with just a magnitude (but no direction) we call it a scalar. But my displacement would be 5 m due East. As displacement has both a magnitude and a direction, we call it a vector.
We measure time in seconds. We will use the variable t for time. The elapsed time for a certain action would be ΔT. The Greek letter delta, Δ, is used to represent a change in a quantity. If we are talking about a reoccurring event (such as the orbit of the Earth around the sun) we talk about the Period of time T, with a capitol T.
For longer periods of time we will often use the conventional minutes, hours, days, or years. For shorter periods of time will often use exponential notation or may use milliseconds, microseconds, picoseconds, or femtoseconds.
For instance, chemical reactions may often take place on the picosecond timescale. Just as when you dance under a strobe like at a cool school dance you can see your movements in stop action. Scientists use pulsed lasers with picosecond and femtosecond pulses to examine dynamics at the molecular level.
Speed and Velocity
Building on changes in position and changes in time, we can examine the rate at which these changes in position take place. How fast are we moving? You probably use the terms speed and velocity interchangeably in your everyday vernacular, but in physics they have distinct meanings. Speed is a scalar and has no direction. Speed can be defined as
speed = distance/elapsed time
Velocity is a vector. We could consider velocity to be speed in a given direction. To calculate the average velocity over a period of time, we use displacement and elapsed time.
Where v is velocity, x is position, t is time. The Greek letter delta, Δ, means a change in a quantity, such as the change in position or the change in time. The bar over the velocity v means the terms in averaged. For instance, Δx = xf – xo , or the change is position equals the difference of the final position and the original positions.
Our first set of problems will involve the above kinematic equation.
Problem Solving Method
When solving physics problems, it is useful to follow a simple problem solving strategy. Although at first, it may be easy to solve some problems in your head, by following this strategy you will develop good problem solving habits. Just as you must develop good habits by brushing your teeth every day, you should attempt to follow the following methodology for solving physics problems. The first step is Step 0 because it does not always apply.
Step 0: Draw a picture of the problem if appropriate.
Step 1: Write down the given information
Step 2: Write down the unknown quantity you are trying to find out
Step 3: Write down the physics equations or relationships that will connect your given information to the unknown variables.
Step 4: Perform algebraic calculations necessary to isolate the unknown variable.
Step 5: Plug in the given information to the new equation. Cancel appropriate units and do the arithmetic.
Example 1: A robot travels across a countertop a distance of 88.0 cm, in 30 seconds. What is the speed of the robot?
In this case, we do not need to do any algebra.
Significant figures: At this point we should not how many significant figures our answer has. Your final answer cannot have more information that your original data. We were presented with a distance and a time with only 3 significant figures, therefore our final answer cannot have more precision than this.
Now let us look at a problem which does require some algebra.
Example 2: The SR-71 Blackbird could fly at a speed of Mach 3, or 1,020 m/s. How much time would it take the SR-71 to take off from Los Angeles and fly to New York City via a path which is a distance of 5500 miles.
You should note that you need to convert miles to meters, remembering that 1 mile = 1600 m
First we need to algebraically isolate the variable t .First we multiply both sides by t, and t cancels on the right hand side of the equation.
Then dividing both sides by v gives us
Now, plugging in for distance and speed gives us
Note the units and the number of significant digits. Because one piece of our original data (distance) only had two significant digits, we have to round off our final answer to 2 significant digits. Also, look at the cancelation of units. The meters in the units cancel. Our units have the reciprocal of a reciprocal, thus the final units are in seconds, which you might have guessed since we are working with time. For ease of perspective we converted these units into minutes.
Average velocity vs instantaneous velocity
Another important distinction is finding an average value or the velocity versus the velocity at a given instant in time. To find an average velocity we only the measure the change in position and the total elapsed time.
However, finding the velocity at a given instant can be tricky. The elapsed time for an instant has no finite length. Similarly, a physical position in space has no finite size. To calculate this using equations we would have to reduce the elapsed time to a near infinitesimally small amount of time. Mathematically, this is the basic for calculus which was developed separately by both Newton and Leibniz. In standard calculus notation we would say the instantaneous velocity can be expressed as
In our next lesson we will learn how to determine the instantaneous velocity using graphical techniques.
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When a person has a heart attack, the heart repairs its damaged muscle by forming scar tissue. As a result, the heart never truly goes back to the way it was. But when a zebrafish has a heart injury, like having a large chunk of it chopped off, it grows a brand new piece to replace it.
Two independent reports published in the journal Nature show that within days of an injury to its heart, the zebrafish has the remarkable ability to regenerate most of the missing cardiac tissue using mature heart cells–not stem cells, as some researchers had suspected.
The findings help explain why human beings can’t regenerate a heart or missing limbs. The reports contradict a previous study (pdf) done by one of the research teams in 2006 that suggested that stem cells, the general all-purpose cells that develop into all the mature and functional cells of the body, were responsible for self-repair.
The finding suggest that doctors have been on the wrong track with recent stem cell-based therapies for heart attack patients. Many heart patients have received injections of stem cells, often ones taken from their own bone marrow. But the beneficial effects have generally been unremarkable [The New York Times].
In one study, a team led by Chris Jopling and Juan Carlos Izpisúa Belmonte genetically engineered the fish’s heart muscle cells so that when they proliferated they would synthesize a fluorescent green protein [The New York Times].Then they chopped off part of the fish’s heart and watched to see if the fish would employ stem cells to regrow the heart or use mature heart muscle cells, known as cardiomyocytes.
In just a few days, scientists found the zebrafish had regrown the missing piece of heart. On further observation, scientists found that all the cells in the new part of the heart glowed green, proving that existing heart muscle cells were the principal or only source of the new tissue [The New York Times]. Further experiments showed that the cardiomyocytes near the injury site seem to take a step backward in development, detaching from one another and losing their typical shape—presumably to make it possible for them to start dividing again as they replenish the lost tissue [ScienceNOW]. Experiments conducted by Kenneth Poss, the researcher behind the 2006 study, showed similar results. Both teams say the next step is to identify the cellular signals that trigger the regeneration process.
The scientists say that prior to heart failure, mammalian heart cells go into a state called hibernation, where the muscle cells stops contracting in an effort to save themselves. Hibernating cardiomyocytes are also seen in zebrafish, but unlike the mammal cells, the fish cells then take another step and begin proliferating. Scientists are trying to understand what gives the fish cells the ability to start multiplying, and hope to conduct further studies on mice to see whether mammalian cells can be induced to follow suit. “Maybe all they need is a bit of push in the right direction,” Jopling said [HealthDay News].
80beats:Injecting Special Protein Could Make Hearts Heal Themselves
80beats: Could Stem Cells Patch Up a Broken Heart?
80beats: Researchers Could Grow Replacement Tissue to Patch Broken Hearts
80beats: Harvesting Infant Hearts for Transplants Raises Ethical Questions
80beats: The Upside of Nuclear Testing: Traceable Radioactivity in Our Heart Cells
Image: Chris Jopling. The green-glowing heart cells are shown at 7, 14, and 30 days after injury.
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As a native Marylander, I’ve had many discussions with friends about whether we can call it a Southern state. You could say it’s in “Dixie,” which (according to one historical interpretation from this Civil War fact book) means south of the Mason-Dixon Line. One could also argue that because it fought for the North in the Civil War, Maryland should be considered a Northern state. However, we can’t forget that Maryland was a slave state that was chock full of Southern sympathizers during the war.
For evidence, just look up the official state song that remains on the books. You might be surprised (or perhaps offended) at the lyrics. According to this NPR story, a group of active fourth-graders were certainly offended when Linda Tuck, a school library “media specialist,” led their study and discussion of the song. Here are some of the lines seen as offensive:
“The despot’s heel is on thy shore, Maryland!”
“Huzza! She spurns the Northern scum!”
By the way, that “despot” refers to the revered Abraham Lincoln. James Ryder Randall wrote the poem in 1861, after riots in Baltimore led to the deaths of a few civilians, according to Dissonance by David Detzer.
Tuck took a vote and found that the school children wanted to see the lyrics changed. They then wrote letters to state delegates, and now a bill is in the works. Delegate Pamela Beidle, who introduced the bill, wants to use a different poem written in 1894 for the lyrics of the song.
According to a local news article, the bill does have its critics, who say that the song’s a reminder of a part of Maryland’s history that is too often forgotten. Others would simply rather leave it up to voters.
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Snapper, New Zealand (Tai)
Snapper are found in subtropical regions of the western Pacific Ocean including New Zealand, Australia, China and Japan.
In New Zealand, Snapper are a commercially important fishery. Due to prudent fisheries management, most Snapper populations in New Zealand are stable or recovering from their previously overfished status.
Juvenile Snapper inhabit muddy estuaries, while adults mostly inhabit rocky reefs, but are also found in mud and sea grass habitats.
Most New Zealand Snapper are caught using longlines, which can result in the incidental catch of seabirds.
This fish may have high levels of mercury that could pose a health risk to adults and children. More mercury info here.
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Some time in the past, before the ice age, most of western North America (and probably the whole world) was accurately mapped by a technologically advanced people. Who these people were and what technology they used is lost to us, but their maps remain as evidence that they did indeed accomplish the task. These ancient source maps were used by mapmakers in the 1600 to 1700s to fill in the vast unknown areas on the western side of North America. The recent mapmakers had no idea what was there, nor did anyone else, but they had source maps that showed the area as an island and they used them to fill in the gaps.
When were these source map made? They had to be made before the end of the ice age, because at the end of the ice age, the great ice dam holding back water in a huge lake finally gave way and the Grand Canyon was carved in just a few weeks. The Grand Canyon does not appear on any maps of California as an island that I have found, and is certainly not on the map used for this study, the Vingboons map of 1651. In fact, on the Vingboons map, two rivers cross the location of the Grand Canyon. This creates a problem, because the ice age supposedly reached a maximum 18,000 years ago (see Wikipedia article), putting the date for modern man well before that. This pushes the date back into the realm of the Neanderthals, or even into the Paleolithic period, when we were supposed to be only capable of using stone tools.
An even greater problem is that the map also had to predate the uplift of the Nevada-Utah-Wyoming area that followed the end of the latest continental drift event in North America. (see Wikipedia, Farallon plate) According to continental drift theory, when the continents spread apart, the North America continental plate was pushed over an oceanic plate, which was forced down into the mantle of the earth. The lighter minerals floated up against the bottom of North America, under the Nevada-Utah-Wyoming area. This area was lifted up from sea level (at least in Nevada, where the map shows where the sea encroached) to over 7,000 feet elevation in central Nevada, and similarly across all three states. The routes of rivers changed. The Rio Grande, shown on the Vingboons map as the Rio de Norte, which used to flow into the Gulf of California, was forced to flow to the Gulf of Mexico. The map places a geologically recent date on continental uplift, the uplift having happened after the map was made, putting it within the historical presence of humans on earth. Unfortunately, geology dates the North American continental drift events to the Jurassic period, 200,000,000 to 150,000,000 years ago. How will Science deal with the loss of 150,000,000 years? Since it requires abandoning a well entrenched worldview, it is most likely that the vast majority of academia will simply ignore this study and its implications.
In the following series of articles, I analyze the Johannes Vingboons “California as an Island” map area by area. We will see that the makers of the original map possessed a detailed knowledge of the geography of western North America. Correlation of features on the map to actual locations demonstrates that the map is very accurate. After the analysis of the map I have included some information on the historical mapmaking and exploration of this area by the Spanish after the arrival of Columbus. The Spanish were extremely slow to explore this area, and the information they had was not allowed to be made public because they needed to protect information on their trade routes from their competitors. Vingboons was not using Spanish information to present California as an island.
These articles are my work and the result of my research. I have referenced all the sources I have used. None of these sources presents “California as an Island” as anything more than a myth.
I graduated from UCLA in 1976 from the School of Engineering. I followed the course of study in chemical engineering. I was introduced to the whole topic of California as an island in about 2008 by Cliff Paiva, who was also researching the locations of features on the map. We have taken different paths in our efforts to decipher the map, but I much appreciate Cliff’s getting me started.
If you have any questions regarding these articles, you can email me at [email protected]
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Transformations in the Coordinate Plane
Transformations in the coordinate plane are often represented by "coordinate rules" of the form (x, y) --> (x', y'). This means a point whose coordinates are (x, y) gets mapped to another point whose coordinates are (x', y').
When possible, simple formulas are given for x' and y' in terms of x and y. For example, (x, y) --> (x + y, x – y) is a coordinate rule for some transformation and maps the points (0, 0), (2, 0), (2, 5), and (0, 5) as follows:
(0, 0) --> (0, 0)
(2, 0) --> (2, 2)
(2, 5) --> (7, –3)
(0, 5) --> (5, –5)
This transformation is not an isometry (it changes the size of any figure) and the image of the blue rectangle with those vertices is the red rectangle:
Translations of geometric figures in the coordinate plane can be determined by translating the x- and y-coordinates of points. Horizontal and vertical translations are the easiest. All other translations can be thought of as a composition of horizontal and vertical translations. The following examples illustrate this.
Example 1: Give a coordinate rule for translating a figure horizontally by 3 units.
Solution: A horizontal translation just changes the x-coordinates of all points, so the rule is (x, y) à (x + 3, y). To illustrate, the blue rectangle with vertices (0, 0), (2, 0), (2, 5), and (0, 5) is translated to the red rectangle with coordinates (3, 0), (5, 0), (5, 5), and (3, 5):
Example 2: Give a coordinate rule for a translation by a distance of 4 units at 30o.
Solution: Consider a point with coordinates (x, y) and its image with coordinates (p, q)
Draw a right triangle with the point and its image as the endpoints of the hypotenuse. This is a 30-60-90 triangle, so the side opposite the 30o angle is half the hypotenuse and the other side is that times the square root of 3. Therefore we have the following picture:
From this picture we see that
and q = x + 2
Therefore the coordinate rule is: (x, y) -->
When a point is reflected in a line, the line is the perpendicular bisector of the segment joining the point and its image. We will only consider coordinate rules for reflections in horizontal and vertical lines, and in the lines y = x and y = –x since the rules for lines in general involve messy details beyond the scope of this course.
Example 3: Give a coordinate rule for reflecting in the line vertical line x = 3.
Solution: Consider a point (x, y) and its image (p, q):
The y-coordinate of the image is the same as the y-coordinate of the preimage, so q = y. Since the line x = 3 bisects the segment from the point to its image, the horizontal distances from the point to the line and its image to the line are equal, so
3 – x = p – 3
Adding 3 to both sides tells us that p = 6 – x. Therefore the coordinate rule is:
(x, y) --> (6 – x, y)
Example 4: Give a coordinate rule for reflecting in the line y = x.
Solution: Again let the point and its image have coordinates (x, y) and (p, q), respectively. The line y = x is a 45o line through the origin, and the relation between the point and its image looks like this:
If we draw horizontal and vertical segments from the axes through the points and to the line y = x, we have the following:
Since the green line is at 45o, we can focus on two squares to see that q = x and p = y:
Thus, the coordinate rule is: (x, y) --> (y, x)
That is, when reflected in the line y = x, the coordinates of any point are transposed.
Coordinate Rules for Reflections
In general, the following coordinate rules for reflections can easily be established:
Reflection in x-axis: (x, y) --> (x, –y)
Reflection in y-axis: (x, y) --> (–x, y)
Reflection in y = x: (x, y) --> (y, x)
Reflection in y = –x: (x, y) --> (–y, –x)
We will only consider rotations about the origin of multiples of 90o.
Example 5: Give a coordinate rule for a rotation about the origin of 90o (counterclockwise).
Solution: Such a rotation is equivalent to reflections in two lines that intersect at the origin and are 45o apart. We could use the x-axis as the first line and the line y = x as the second. The composite of these reflections is:
(x, y) --> (x, –y) --> (–y, x)
That is, a rotation about the origin of 90o has the coordinate rule: (x, y) --> (–y, x)
Coordinate Rules for Rotations
In general, we can state the following coordinate rules for (counterclockwise) rotations about the origin:
For a rotation of 90o: (x, y) --> (–y, x)
For a rotation of 180o: (x, y) --> (–x, –y)
For a rotation of 270o: (x, y) --> (y, –x)
Dilations in the Coordinate Plane
First consider dilations with the origin as center. Then the coordinate rule for a dilation with scale factor k is simply this:
(x, y) --> (kx, ky).
Example 6: Triangle ABC has coordinates A(–1, –3), B(1, 1) and C(2, –3). Triangle DEF has coordinates D(2, 6), E(–4, 6) and F(–2, –2). Show that triangle DFE is the image of triangle ABC under a dilation with center at the origin, and find the scale factor.
Solution: The image of A is given by (–1, –3) --> (–1k, –3k). If D is that image, then –1k = 2 and –3k = 6. Both give k = –2. If we apply this dilation to B and C, we find that F is the image of B and E is the image of C.
Dilations with Center other than the Origin
A dilation with any point other than the origin as the center of dilation can be accomplished by first translating the center of dilation and figure so the origin becomes the center, and then translating back:
Example 7: Find a coordinate rule for the dilation with center (5, –3) and scale factor 2.
Solution: If (x, y) is a point on a figure to be dilated, we first translate left 5 and up 3. This gives us the point (x – 5, y + 3), and the origin becomes the center of the dilation. The dilation now gives us (2x – 10, 2y + 6). Then we translate back--that is, right 5 and down 3, which gives us (2x – 10 + 5, 2y + 6 – 3). So the coordinate rule is:
(x, y) --> (2x – 5, 2y + 3)
Return to Lesson 5
| 4.399564 |
Celebrate being an American on the Fourth of July, Constitution Day, Citizenship Day, and other special days, but don't stop there. Celebrate year-round with children's books for younger kids to kids in middle school. These recommended children's books include books about the Constitution and the Declaration of Independence, a children's cookbook, a poetry book, book of tall tales, stories about the White House and its occupants, an illustrated version of the poem "America the Beautiful," and children's books about some of our important national symbols, like the Statue of Liberty. Keep scrolling down to see all 10 of the books I recommend.
1. Lady Liberty: A Biography
Doreen Rappaport’s Lady Liberty: A Biography is the story of the Statue of Liberty, from the idea to the planning, fundraising and building to the celebration when it was completed. The book, in picture book format, features large and dramatic watercolor, ink and pencil illustrations by Matt Tavares. I recommend Lady Liberty for children eight and older, younger if they have visited the Statue of Liberty. Because of the dramatically told story and the large amount of fascinating information in the book, I would also highly recommend Lady Liberty for teens and adults. Compare prices. (Candlewick Press, 2008. ISBN: 9780763625306) Read my review of Lady Liberty: A Biography.
2. Our White House: Looking In Looking Out
Our White House: Looking In Looking Out is a large book, with a great many entries by a variety of authors and illustrators, and including both historical fiction and nonfiction. While the book is sometimes confusing, it is filled with fascinating stories and facts, presented in a variety of ways. The book should be of interest to 9-14 year olds and to families looking for a book related to American history to enjoy together. Compare prices. (Candlewick Press, 2008. ISBN: 9780763620677) Read my review of Our White House: Looking In Looking Out.
3. America the Beautiful
Chris Gall's powerful artwork is the perfect complement to the words of the poem "America the Beautiful" by Katharine Lee Bates. The illustrations are reminiscent of WPA murals. Even children who are used to singing "America the Beautiful," the song based on Bates' poem, may not have really thought about the meaning of the words until seeing this book. Compare prices. (Little, Brown and Co., 2004. ISBN: 0316737437) Read my review of America the Beautiful.
4. Celebrate Independence Day
If you are looking for a nonfiction children's books about Independence Day for kids in elementary school, I recommend Celebrate Independence Day by Deborah Heiligman. The book is illustrated with high quality color photographs, accompanied by brief paragraphs that stress the history of Independence Day in the U.S. and Fourth of July traditions and festivities. Compare prices. (National Geographic Society, 2007. ISBN: 9781426300752) Read my review of Celebrate Independence Day.
5. Shh! We're Writing the Constitution
I recommend this book for 8-12 year olds, particularly on Constitution Day. Jean Fritz, who is known for her children’s books about American history, wrote the book. Award-winning artist Tomie dePaola provided the entertaining illustrations. While the subject is serious and the content rich with information, the author and illustrator tackle the serious subject matter with enough humor to keep the readers’ interest. Compare prices. (Putnam Publishing Group. 1987. ISBN: 0399214038)
6. The United States Cookbook
As the subtitle states, this children’s cookbook contains recipes for “Fabulous Food and Fascinating Facts from All 50 States.” For each state, there’s a map, illustrations of several state symbols, information about the state, fun food facts about the state, plus a recipe related to the state. Recipes include key lime pie from Florida and Swedish meatballs from Minnesota. The cookbook also contains sections on cooking skills and safety rules. Compare prices. (John Wiley & Sons, 2000. ISBN: 9780471358398)
7. The Declaration of Independence
This nonfiction book contains the full text of the Declaration of Independence inscribed by Sam Fink and accompanied by his witty illustrations. The book also contains a four-page 1748-1776 events chronology, a four-page glossary, and a page of recommended online and print resources. I recommend it for children 10-14 and would include it on your Constitution Day and Citizenship Day booklist. Compare prices. (Scholastic Inc., 2000. ISBN: 9780439407007)
8. American Tall Tales
The nine stories in Mary Pope Osborne’s 115-page collection of American tall tales feature, among others, Paul Bunyan, Johnny Appleseed, John Henry, and Sally Ann Thunder. A U.S. map shows the location of each tale. Each story includes historical notes and contains a number of colorful wood engravings by Michael McCurdy. Compare prices. (Alfred A. Knopf, 1991. ISBN: 0679800891)
9. Uncle Sam and Old Glory
Delno C. West and Jean M. West provide a brief look at 15 different American symbols, each illustrated with a handsome woodcut by Christopher Manson. The symbols include the American flag, Smoky the Bear, the Liberty Bell, and Uncle Sam. While I would not have selected all of the symbols chosen, I’d recommend the book. Compare prices. (Atheneum Books for Young Readers, 2000. ISBN: 0689820437)
10. My America: A Poetry Atlas of the United States
This book of poetry selected by Lee Bennett Hopkins is divided into sections representing different regions of the U.S., each with a map and information about the states. The illustrations, paintings by Stephen Alcorn, and the poetry, such as Nikki Giovanni’s “Knoxville, Tennessee,” create a sense of place for the reader. Compare prices. (Simon & Schuster, 2000. ISBN: 0689812477)
| 3.048599 |
Investigation of Neurofeedback With Real-Time fMRI in Healthy Volunteers and Patients With Hyperkinetic Movement Disorders
- Many people can learn to use feedback about brain activity to modify that activity, but is it not known if people with Tourette syndrome can modify their brain activity.
- Researchers have evidence that certain areas of the brain are involved in causing tics in people with Tourette syndrome. If people with Tourette syndrome can use feedback about brain activity to modify activity in those parts of the brain, they may be able to modify their brain activity to help control the tics.
- To determine if people with and without Tourette syndrome can learn to use thought to control brain activity.
- To test whether people who have Tourette syndrome can learn to control brain activities, possibly helping to control tics.
- Healthy volunteers ages 18 and older who are right-handed and are willing to not consume caffeine or alcohol for 24 hours before the study visit.
- Patients with Tourette syndrome who have tics that can be observed and studied.
- All participants must be able to undergo magnetic resonance imaging (MRI) scans.
- Healthy volunteers (two visits to the NIH Clinical Center over a 2- to 4-week period; visit may last up to 3 hours):
- Screening visit, including physical examination and medical history, and a magnetic resonance imaging (MRI) scan if the individual has not had one performed at the National Institutes of Health in the past year.
- Study visit: Functional MRI (fMRI) scan to allow researchers to see if volunteers can learn to control their brain activity during a scan. Volunteers will be asked to complete tasks as directed during the fMRI scan.
- Patients with Tourette syndrome (three or four outpatient visits over a 4- to 6-week period; each visit may last up to 4 hours):
- Screening visit, including physical examination and medical history, and an MRI scan if the individual has not had one performed at the National Institutes of Health in the past year.
- Evaluation visit to ask questions about Tourette symptoms and to have patients complete questionnaires about their tics and their mental health.
- Study visit: fMRI scan to allow researchers to see if patients can learn to control their brain activity during a scan. Patients will be asked to complete tasks as directed during the fMRI scan.
- Final visit: Researchers will ask questions about tic symptoms, have patients complete questionnaires, and perform a brief exam. Afterward, patients will have an fMRI scan similar to the previous one.
- All participants will be paid a small amount of money in compensation for their participation in the study.
|Study Design:||Time Perspective: Prospective|
|Official Title:||Investigation of Neurofeedback With Real-Time fMRI in Healthy Volunteers and Patients With Hyperkinetic Movement Disorders|
|Study Start Date:||April 2009|
The objective of this study is to see if healthy volunteers and patients with hyperkinetic movement disorders such as Tourette Syndrome (TS) are able to learn how to alter their brain activity using feedback during functional magnetic resonance imaging (fMRI), and whether such feedback training can lead to improvement in symptoms in TS patients.
This study is to be carried out in three phases. In Phase 1 we will study the feedback technique using fMRI with right-handed adult healthy volunteers, in Phase 2 we intend to study if right-handed adult patients with TS are also able to learn the feedback technique, and in Phase 3 we intend to study whether feedback training with fMRI leads to improvement in symptoms in TS patients and whether patients were able to retain the ability to alter their brain activity.
Phase 1: Healthy volunteers will be shown an image that corresponds to their brain activity being measured continuously during fMRI scanning and asked to attempt to alter this activity first with a simple finger-tapping task and then with their thoughts. Phase 1 will require two visits (one screening and one scanning) (completed).
Phase 1a: A pilot study evaluating the ability of healthy volunteers to learn to modulate their own brain connectivity using feedback of connectivity patterns between two motor regions during a real-time fMRI paradigm. Phase 1a will require three visits (one screening and two scanning with evaluation).
Phase 2: TS patients will be studied to see if they can learn to alter their brain activity in a similar way as the healthy volunteers. Patients will have their symptoms videotaped and a brief interview after scanning. Phase 2 will require three visits (one screening, one evaluation, and one scanning).
Phase 3: The effect of altering brain activity in a specific brain area on symptoms in TS patients will be studied. Patients will be asked to continue to focus their thoughts as they did during feedback scanning any time that they feel an urge prior to a tic or every hour while awake, whichever is more frequent, until a follow-up visit and fMRI scan two or three days later. Phase 3 will require four visits (one screening, one evaluation, one scanning, and one follow-up). No visit will last more than 4 hours.
The primary outcome for Phases 1 and 2 is the difference in brain activation within a specific area after feedback training compared to a baseline, and for Phase 3 it is the difference in symptoms measured by a TS rating scale before fMRI scanning compared to two or three days after learning the feedback technique. Secondary outcomes for all three phases include the changes in activation in a specific brain area compared to a baseline after repeated scanning trials and when no feedback image is displayed.
|Contact: Elaine P Considine, R.N.||(301) [email protected]|
|Contact: Mark Hallett, M.D.||(301) [email protected]|
|United States, Maryland|
|National Institutes of Health Clinical Center, 9000 Rockville Pike||Recruiting|
|Bethesda, Maryland, United States, 20892|
|Contact: For more information at the NIH Clinical Center contact Patient Recruitment and Public Liaison Office (PRPL) 800-411-1222 ext TTY8664111010 [email protected]|
|Principal Investigator:||Mark Hallett, M.D.||National Institute of Neurological Disorders and Stroke (NINDS)|
| 3.070024 |
T-Reg Cell Kinetics, Stem Cell Transplant, REGALE
Patients have a type of blood cell disorder that is very hard to cure. We are now suggesting a treatment that might help patients live longer without disease than other treatment plans would. This treatment is known as a stem cell transplant. We believe this may help patients as it allows us to give much stronger doses of drugs and radiation to kill the diseased cells than we could give without the transplant. We also think that the healthy cells may help fight any diseased cells left after the transplant.
Stem Cells are special "mother" cells that are found in the bone marrow (the spongy tissue inside bones), although some are also found in the bloodstream (peripheral blood). As they grow, they become either white blood cells which fight infection, red blood cells which carry oxygen and remove waste products from the organs and tissues or platelets, which enable the blood to clot. For the transplant to take place, we will collect these stem cells from a "donor" (a person who agrees to donate these cells) and give them to recipient. Patients do not have a sibling that is a perfect match, so the stem cells will come from a donor who is the best match available. This person may be a close relative or an unrelated person whose stem cells best "matches" the patients, and who agrees to donate stem cells. Before the transplant, two very strong drugs plus total body irradiation will be given to the patient (pre-conditioning). This treatment will kill most of the blood-forming cells in the bone marrow. We will then give the patient the healthy stem cells. Once these healthy stem cells are in the bloodstream they will move to the bone marrow (graft) and begin producing blood cells that will eventually mature into healthy red blood cells, white blood cells and platelets.
This research study will also use CAMPATH-1H as a pre-treatment. CAMPATH-1H is an antibody against certain types of blood cells. CAMPATH-1H is important because it stays active in the body for a long time after infusion, which means it may work longer at preventing GvHD symptoms.
The stem cell transplant described above is considered to be "standard" treatment. We would like to collect additional blood as described below in order to evaluate how the immune system is recovering.
We are asking permission to draw blood from the patient so that we can measure the number of certain blood cells called T regulatory cells. T regulatory cells are special immune cells that can control or regulate the body's immune response. We want to determine whether T regulatory cells are important participants in graft versus host disease (GVHD), infection and relapse. In GVHD, certain cells from the donated marrow or blood (the graft) attack the body of the transplant patient (the host). GVHD can affect many different parts of the body. The skin, eyes, stomach and intestines are affected most often. GVHD can range from mild to life-threatening. We do not know whether T regulatory cells can modify these conditions. We want to measure these T regulatory cells and learn if these cells do influence these conditions. If we learn that T regulatory cells do affect these conditions, then it may be possible to modify these cells for the benefit of transplant patients.
Non Hodgkin Lymphoma
Drug: ARA C
Radiation: Total Body Irradiation (TBI)
Procedure: Stem Cell Infusion
|Study Design:||Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
|Official Title:||T-Regulatory Cell Kinetics for Patients Receiving Alemtuzamb and Undergoing Stem Cell Transplantation From HLA Mismatched-Related, or HLA Matched, or One Antigen Mismatched-Unrelated Donors|
- To define the biologic recovery and behavior of T reg cells for pts undergoing stem cell transplant [ Time Frame: 3 years ] [ Designated as safety issue: No ]
- To determine that the administration of Campath 1H as part of conditioning therapy to patients undergoing stem cell transplantation from mismatched related donors or from matched unrelated donors permits T regulatory cell recovery. [ Time Frame: 3 years ] [ Designated as safety issue: No ]
|Study Start Date:||October 2007|
|Estimated Study Completion Date:||May 2013|
|Estimated Primary Completion Date:||May 2013 (Final data collection date for primary outcome measure)|
Experimental: Stem Cell Transplant
All patients will receive Ara C IV every 12 hours for 6 doses starting at 1400 hours on day -8. Cyclophosphamide IV once daily on day -7 and day -6 starting at 1400 hours. MESNA will be administered 15 minutes prior to each dose of Cyclophosphamide and 3, 6, 9, and 12 hours after each dose of Cyclophosphamide. Campath 1h will be given on day -4, day -3, day -2 and day-1. TBI (Total Body Irradiation) will be delivered in 8 fractions of 1.75 Gy in two fractions on day -4, day -3, day -2, and day -1. Stem cell Infusion are infused on day 0.
Drug: ARA C
Ara C (3000 mg/m2) IV every 12 hours for 6 doses (days -8 to -5)
Other Name: CytarabineDrug: Cyclophosphamide
Cyclophosphamide (45mg/kg) IV once daily on day -7 and day -6
Other Name: CytoxanDrug: MESNA
MESNA (45mg/kg; divided into 5 doses) will be administered 15 minutes prior to each dose of Cyclophosphamide and 3, 6, 9, and 12 hours after each dose of Cyclophosphamide.
Other Name: MesnexRadiation: Total Body Irradiation (TBI)
TBI: total dose 14.0 Gy, will be delivered in 8 fractions of 1.75 Gy in two fractions on day -4, day -3, day -2, and day -1
Other Name: RadiationBiological: Campath-1h
CAMPATH (3 mg IV for patients between 5 and 15 kg; 5 mg for patients between 16 and 30 kg; and 10 mg for patients greater than 30 kg) will be given on day -4, day -3, day -2 and day-1.
Other Name: AlemtuzumabProcedure: Stem Cell Infusion
Stem cells are infused on day 0
To participate in this transplant, the patient will need to have a central line.
Before the transplant we will test the blood for viruses which can cause problems after the transplant. These viruses include Hepatitis B, cytomegalovirus and HIV. If the patient is positive for the AIDS virus, they will not be able to undertake the transplant.
Standard therapy: The patient will be given 6 doses of chemotherapy with a drug called Ara C in high doses (every 12 hours) which will begin 8 days before the stem cell transplant. Then, another chemotherapy drug called cyclophosphamide will be given in high doses by vein for two days on the 7th and 6th days before the transplant. A drug called MESNA will be given with cyclophosphamide. MESNA is used to decrease the side effects caused by cyclophosphamide. The patient will also receive an antibody called Campath (each day for 4 days before the transplant) to help destroy the immune system so that there is less host resistance to the growth of the donor cells. Radiation treatment will be given to the entire body on each day for 4 days before transplant. This will be given 2 times a day for 4 days. The chemotherapy and radiation treatment will last 8 days. If the patient has a diagnosis of T-cell Lymphoma, they will not be given the Ara-C.
Extra bone marrow tests may be recommended by the physician to check on the patients condition, especially if the marrow is slow to grow.
The day after the radiation treatment is completed; the patient will receive the healthy stem cells by vein. Once in the bloodstream, these stem cells will go to the bone marrow and should begin to grow.
In prevention of GvHD, the patient will also receive medicine called FK506 as well as low dose methotrexate. The FK506 will be given intravenously initially starting 2 days before the transplant and later by mouth (when they are able to take oral medications). This drug will be given each day for several weeks. Four doses of low dose methotrexate will be given intravenously. The methotrexate will be given on the day after the transplant, 3, 6 and 11 days after the transplant. If the GVHD cannot be controlled with FK506, other medicines may need to be given. The doctor will describe these medicines at that time.
Blood samples for research: To study how these cells are working in the patients system, blood samples will be taken each month for six months, at nine months, at one year, 2 years and 3 years following transplant. Approximately 6-8 teaspoons of blood will be collected each time. The total blood drawn for this study over three years should not exceed 1 and 3/4 cups. This amount is considered safe in adults. The amount of blood collected will be decreased in children and/or in patients where this amount of blood collection would not be appropriate.
|United States, Texas|
|Texas Children's Hospital|
|Houston, Texas, United States, 77030|
|Principal Investigator:||Robert Krance, MD||Baylor College of Medicine|
| 3.631971 |
Small cetacean species may not survive another decade warns new landmark publication
IUCN-The World Conservation Union, Gland, Switzerland, 14.05.03. A new publication on the status of the world's cetaceans - whales, dolphins and porpoises, offers a stark warning that the smaller, lesser-known species such as the baiji (or Yangtze River dolphin) may not survive the next decade.
Dolphins, Whales and Porpoises: 2002-2010 Conservation Action Plan for the World's Cetaceans, is an authoritative, benchmark publication providing the latest information on the status of cetaceans worldwide while recommending actions that could help save the most threatened species. As a guiding document for all those involved in cetacean conservation, it will be used by scientists in the field and academic institutions, as well as those making critical decisions about the future of these species and their habitats.
This new publication is the most recent of three Action Plans compiled by the Cetacean Specialist Group (CSG) of IUCN's Species Survival Commission during the past 15 years. The Group has over 75 members worldwide contributing significant experience and expertise to the growing pool of knowledge about cetaceans. This Action Plan provides scientific information about the current status of cetaceans worldwide; identifies threats to their survival and ways to further understand and assess these threats; and recommends specific conservation actions.
With ongoing revision and debate about how they should be classified, there are currently 86 recognised cetacean species. These animals live in a variety of habitats, from the high seas far beyond the national jurisdiction of any country, to the shallow freshwater rivers, lakes and coastal waters of southern Asia and South America. Some species are highly migratory, requiring vast areas of ocean to move between feeding and calving waters, whilst others reside in particular sections of rivers and coastal waters.
"Some of the great whales such as the blue, humpback, sperm and right whales often receive a lot of attention. They are magnificent animals, and certainly important to the CSG's mission. The Group focuses, however, on smaller species, often lesser-known and in developing countries, that are particularly threatened with extinction," says Dr Randall Reeves, Chair of the CSG.
Swimming against extinction
To date, humans have not caused the extinction of any cetacean species. This claim may not hold true for much longer though. According to former CSG Chair, William F. Perrin, "it seems unlikely that the baiji [or Yangtze dolphin, Lipotes vexillifer] will still be around when the next new Action Plan is formulated eight or ten years from now". The baiji, a freshwater dolphin with its distribution now limited to the main channel of the Yangtze River in China, is considered the most endangered cetacean. From surveys conducted in 1985 and 1986, the total baiji population was guessed to number around 300 animals. Between 1997 and 1999, extensive surveys sighted only 21-23 dolphins. The new Action Plan states that there may be no more than a few tens of Yangtze dolphins in existence.
Of the species/populations that have been assessed against the IUCN Red List of Threatened Species criteria, the baiji, vaquita (Gulf of California porpoise, Phocoena sinus), and several geographical populations of whales and dolphins are categorised as Critically Endangered. Northern Hemisphere right whales (Eubalaena glacialis and E. japonica), the blue whale (Balaenoptera musculus), Hector's dolphin (Cephalorhynchus hectori) and Ganges/Indus river dolphins (Platanista gangetica) are listed as Endangered. There are others yet to be formally assessed, some of which are known to be in serious danger of extinction.
Threats facing cetaceans
The first Cetacean Action Plan, published in 1988, expanded awareness of not only the great whales (the 14 recognised baleen species and the toothed sperm whale), but also the approximately 70 species of smaller and medium-sized species. In 1994, the second Action Plan emphasised the vulnerability of freshwater and coastal cetacean populations, highlighting their geographically restricted ranges and dependence on resources also used by humans.
Perrin sees a glimmer of conservation success, but notes that urgent action is warranted to deal with the extinction crisis facing particular species and populations. "Some progress has been made, but as the present plan testifies, grave threats to the continued existence of many cetaceans still exist, and some threats are worsening," says Perrin. "Cetacean diversity, like all biodiversity worldwide, is crumbling so we must redouble our efforts," he concludes.
Traditional threats to cetaceans such as the deliberate killing of some species for food and predator control continue. These are increasingly accompanied by additional threats: animals die from entanglement in fishing gear; collisions with powered vessels injure and kill cetaceans; some species are targeted to supply the demand from oceanaria for live animals; changing ecosystem dynamics resulting from either industrial or intensive artisanal fishing may be depleting food sources for some species; activities such as the construction of dams, irrigation infrastructure, and aquaculture facilities degrade habitat; in addition to longstanding concerns about acoustic disturbance, new types of military sonar apparently can cause lethal trauma to deep-diving cetaceans.
Cautious optimism for some populations
Whilst recognising that the status of many cetaceans is worsening and threats to their survival are in many cases increasing, cautious optimism is now being expressed about the effectiveness of past and ongoing conservation actions for some populations of great whales. Right and bowhead whales have been protected from commercial whaling under international law since 1935, gray whales since 1946, and humpback whales (Megaptera novaeangliae) and blue whales since the mid-1960s. Add to this the continuing worldwide moratorium on commercial whaling which took effect in 1986, and it appears that a lot of work has been done by many individuals over the years to achieve effective conservation measures for cetaceans across the globe.
Despite the fact that many thousands of right, blue, and humpback whales were taken illegally in the Southern Ocean and North Pacific during the 1950s and 1960s (in some cases putting populations of these species in jeopardy), several populations of southern right whales (Eubalaena australis), humpbacks in many areas, gray whales in the eastern North Pacific, and blue whales in both the eastern North Pacific and central North Atlantic have begun to show signs of recovery.
Recommendations for action
"Over the past 15 years, it has become clear that, in certain cases, existing scientific evidence is sufficient to justify, or indeed require, immediate action. The CSG therefore decided to include a number of recommendations in this Action Plan that go beyond research; these address specific actions that need to be taken to promote the recovery of species or populations immediately threatened with extinction," says Dr Reeves. Amongst others in the publication, recommendations include actions to prevent injury to the baiji from snag-line and electric fishing; eliminate fishing methods that take vaquitas as bycatch throughout their range; and for the Hector's dolphin, endemic to New Zealand, increase the size of existing protected areas to include the harbours and bays in the North Island sanctuary, and also extend the offshore boundaries for both sanctuaries.
Dolphins, Whales and Porpoises: 2002-2010 Conservation Action Plan for the World's Cetaceans is available electronically on this site in .PDF and can be purchased in hard copy from the IUCN World Conservation Bookstore
http://www.iucn.org/bookstore/; Email: [email protected]; tel: +44 1223 277894; fax +44 1223 277175.
Read more on the website of the Wildlife Conservation Society, a key partner in production of the Action Plan.
For more information contact:
Dr Randall Reeves, Chair, IUCN/SSC Cetacean Specialist Group and Action Plan co-author
Tel: +1 450 458 6685 (Canada)
Fax: +1 450 458 7383
Brian Smith - CSG Asia Coordinator and Action Plan co-author
Tel: +66 (76) 383 144 (Thailand)
Email: [email protected] or [email protected]
Andrew McMullin- Communications Officer - Species Programme
IUCN -The World Conservation Union
Tel: +41 (0)22 9990153
Fax: +41 (0)22 9990015
| 3.140008 |
This archived Web page remains online for reference, research or recordkeeping purposes. This page will not be altered or updated. Web pages that are archived on the Internet are not subject to the Government of Canada Web Standards. As per the Communications Policy of the Government of Canada, you can request alternate formats of this page on the Contact Us page.
The Canada we know today comprises ten provinces and three territories. The process leading to the entry of each of these provinces and territories into Canadian confederation is a story worth telling. The following texts present the social, economic and political conditions that existed when these provinces and territories joined Canada. Emphasis is placed on the specific experiences of each province or territory, and on the similarities between the various provinces and territories. You will become acquainted with the principal characters and you will be plunged into the main discussions. You will get an idea of what Canada was like during these various moments in its history.
|Province or Territory||Joined Confederation|
|Prince Edward Island||1873|
| 3.798991 |
Join hundreds of early years practitioners in the TES Early Years group. Find lesson ideas and inspiration, share best practice and get your questions answered by your peers.
What age group?
What's wrong with paper and pencils? Give them a variety of paper and writing implements to choose in your writing area, include different colours and sizes, post-it notes, envelopes, rolls of paper etc. and access to glue sticks, sellotape, paper clips. Have clipboards and pens or pencils, post its, notebooks, exercise books, etc. placed in all your other areas so they can writie while they are there.
At the moment I've got scrolls made from paper discoloured with tea bags and rolled up in my castle role play along with a quill pen made from a feather taped to a biro. I've got a clipboard next to some castle and knights small world play and they use it for noting down the score between two sets of knights, I haven't been able to fathom their rules yet but never mind! I've got small world superhero characters made from laminated photos of some of the boys dressed up and mounted on wooden blocks placed on my Author's table with appropriate vocabulary and small blank books for them to write in, these are well used. Laminated photos of other children are mixed with the wooden fairytale characters in a fairytale small world setting along with a clipboard, I haven't had much writing in that area yet but a lot of verbal story telling. Don't forget paper on clipboards, long rolls of wallpaper as well as whiteboards and pens, chalkboards and large chalks for writing on the ground outside.
In the past I've had paper and a plastic bottle near pirate small world play and they used it for writing messages. It was hard getting the scrunched up paper out of the bottle but certain reluctant boys improved rapidly.
Most important - celebrate any writing that they do. Share it with the class - praise the letter formation, the quantity, the firm positive pencil strokes, the attempt at using letter sounds, anything positive at all - the other children will take their cue from this and want to get in on it.
I agree with InkyP mashed potato is fun and so is paint and sand and mud and ... but in reception they need to use pen/pencil and paper and sometimes reluctant boys have to do things they don't automatically choose. It's not what they use to mark make with it's giving it a purpose that is important and why any child chooses to write.
Our nursery boys were very taken with paper sellotaped to the underside of tables. They lay on cushions and had a lot of fun - good for hand strength too.
Letter formation is of prime importance [sorry to state the obvious] in reception and you need something a lot more structured and, yes, monitor-able than vague squishy activities if you want to make sure it's developing well.
InkyPWhat's wrong with paper and pencils?
Mszbut in reception they need to use pen/pencil and paper and sometimes reluctant boys have to do things they don't automatically choose.
I think you need to be clear whether you want exciting mark making activities or you want to encourage reluctant boys to engage in writing (emergent or more structured) because however exciting the mark making is it is not going to make boys want to write only to make marks, which is fine in itself as it develops lots of skills.
Hi some ideas I use in my room are;
Taping down wall paper and giving a selection of mark making tools- they love this as they feel there writing on the table.
Clip boards everywhere especially in the construction area as they make plans for their models.
Coloured sand in shallow trays to use paint brushes/fingers etc.
Magnifying glasses outside to hunt for words and write them.
Home corner- shopping lists, copying out of catalogues, telephone numbers from the phone book etc.
We put crates tyers and police fancy dress costumes outside and they loved writing the names of who they caught and writing a sign for their police station.
and lots of other random bits and pieces that work with our daily routines in Rec.
Msz I think you need to be clear whether you want exciting mark making activities or you want to encourage reluctant boys to engage in writing (emergent or more structured) because however exciting the mark making is it is not going to make boys want to write only to make marks, which is fine in itself as it develops lots of skills.
Had you said that was what you wanted I would have posted ideas for mark making unfortunately they won't encourage relucatant boys to want to write!
korunot interested in a debate
Come on, Koru - the debate is needed and one day you'll join in with alacrity.
Why are you not interested in debate? Should we not be quetioning our practice?
I'm so pleased we aren't alone in having enthusiastic boys when it comes to reading and writing.
"Driving" the toy cars through paint then driving them around the paper. ~or wheeled vehicles outdoors
Sponge pan scourers in paint. or large sponge floor mops
Bubble wrap is good - get them to paint the bubbly side then lay a sheet of paper on top.
Painting with decorators brushes
Shaving brushes are good in paint, easier than paint brushes for little hands,
feathers in paint
roll tyres/balls through paint
sticks and mud
washing up liquid bottles with water or watery paint
plant sprays and paint
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