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We are banishing darkness from the night. Electric lights have been shining over cities and towns around the world for a century. But, increasingly, even rural areas glimmer through the night, with mixed – and largely unstudied – impacts on wildlife. Understanding these impacts is a crucial conservation challenge and bats, as almost exclusively nocturnal animals, are ideal subjects for exploring the effects of light pollution.
Previous studies have confirmed what many city dwellers have long noted: some bats enjoy a positive impact of illumination by learning to feed on insects attracted to streetlights. My research, however, demonstrates for the first time an important downside: artificial lighting can disrupt the commuting behavior of a threatened bat species. This project, using a novel experimental approach, was supported in part by BCI Student Research Scholarships.
Artificial lighting is a global phenomenon and the amount of light pollution is growing rapidly, with a 24 percent increase in England between 1993 and 2000. Since then, cultural restoration projects have brought lighting to old docks and riversides, placing important river corridors used by bats and other wildlife at risk of disturbance.
Studies of bats' foraging activity around streetlights find that these bats are usually fast-flying species that forage in open landscapes, typically species of Pipistrellus, Nyctalus, Vespertilio and Eptesicus. Such bats are better able than their slower cousins to evade hawks, owls and other birds of prey.
For our study, we chose the lesser horseshoe bat (Rhinolophus hipposideros), a shy, slow-?ying bat that typically travels no more than about 1.2 miles (2 kilometers) from its roost to forage each night, often flying no more than 16 feet (5 meters) from the ground. The species is adapted for feeding in cluttered, woodland environments. Its global populations are reported decreasing and the species is endangered in many countries of central Europe. The United Kingdom provides a European stronghold for the lesser horseshoe bat, with an estimated population of around 50,000.
These bats' slow flight leaves them especially vulnerable to birds of prey, so they leave their roosts only as the light fades and commute to foraging areas along linear features such as hedgerows. Hedgerows are densely wooded corridors of shrubs and small trees that typically separate fields from each other and from roadways. Such features are important commuting routes for many bat species, which use them for protection from predators and the elements. We suspected that lesser horseshoe bats would avoid illuminated areas, largely because of a heightened risk from raptors.
We conducted arti?cial-lighting experiments along hedgerows in eight sites around southern Britain. We first surveyed light levels at currently illuminated hedgerows, then duplicated those levels at our experimental hedgerow sites, all of them normally unlighted. We installed two temporary, generator-powered lights – about 100 feet (30 meters) apart – that mimic the intensity and light spectra of streetlights. Each site was near a maternity colony and along confirmed commuting routes of lesser horseshoe bats.
Bat activity at each site was monitored acoustically, with mounted bat detectors, during four specific treatments: control (with no lights); noise (generator on and lights installed but switched off); lit (full illumination all night for four consecutive nights); and another night of noise only. We identified horseshoe bat calls to species and measured relative activity by counting the number of bat passes per species each night.
We found no significant difference in activity levels of lesser horseshoe bats between the control nights and either of the two noise nights, when the generators were running but the lights were off. The presence of the lighting units and the noise of the generators had no effect on bat activity.
The negative impacts came when we turned on the lights. We documented dramatic reductions in activity of lesser horseshoe bats during all of the illuminated nights. In our study, 42 percent of commuting bats continued flying through the lights; 30 percent reversed direction and left before reaching the lights; 17 percent flew over the hedgerows; 9 percent flew through the thick hedgerow vegetation; and 2 percent circled high or wide to avoid the lights. We also recorded some strange behavior on one night when two bats flew over the hedge in a dark area between two lights, then flew up and down repeatedly, as though trapped between the lights.
We examined the effects of light on the timing of bats' commuting activity. The bats began their commute, on average, 29.9 minutes after sunset on control nights, but 78.6 minutes after sunset when the lights were turned on. Light pollution significantly delayed the bats' commuting behavior. Interestingly, the activity began a few minutes earlier (23 minutes after sunset) on the first, but not the second, noise night. It is possible that some bats emerged early to investigate the generator noise.
We clearly demonstrated how artificial lighting disrupts the behavior of lesser horseshoe bats. We found no evidence of habituation: at least on our timescale, the bats did not become accustomed to the illumination and begin returning to normal activity or timing.
These results suggest that light pollution may fragment the network of commuting routes used by lesser horseshoe bats, causing them to seek alternate, and probably longer, paths between roosting and foraging habitats. For some bats, this increased flight time can increase energy costs and stress, with potential impacts on reproductive success. It is critical, therefore, that light pollution be considered in conservation efforts.
Light pollution is an increasing global problem with negative impacts on such important animal behaviors as foraging, reproduction and communication. Yet lighting is rarely considered in habitat-management plans and streetlights are specifically excluded from light-pollution legislation in England and Wales.
I plan to use these results as the basis for recommendations for changes in policy, conservation and management for bat habitat in areas that are subject to development. This knowledge is fundamental for understanding the factors that impact bat populations not only in the United Kingdom but around the world, and in developing effective bat-conservation actions. I hope these findings will also help guide further research.
Scientists need to determine what levels of lighting particular bat species can tolerate, so we can take appropriate measures to limit the impact. These might include reducing illumination at commuting times, directing light away from commuting routes and constructing alternative flight routes.
We sincerely hope this research and similar studies will cause both officials and the public to think more about the consequences of artificial lighting on bats and other wildlife.
EMMA STONE is a Ph.D. student at the University of Bristol and a researcher at the university's School of Biological Sciences. This project earned her the national Vincent Weir Scientific Award from the Bat Conservation Trust of the United Kingdom. Visit her project website for more information: www.batsandlighting.co.uk.
This research was originally published in the journal Current Biology, with co-authors Gareth Jones and Stephen Harris.
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How to protect your hearing and keep ears safe
About 1 in 10 adults has damaged hearing which can be caused by loud music and noises. Here's Newsround's guide to keeping your ears safe.
Why does loud music harm our ears?
Our ears are sensitive instruments and loud music can damage tiny hairs inside the ear that help us hear properly.
When the hairs are damaged they can't be fixed and a lot of people are left with a ringing or whistling noise in their ears.
We call this tinnitus and people find it very annoying!
How loud is too loud?
Sound is measured in units called decibels. An electric drill makes about 100 decibels of noise - that's pretty loud!
Some music players can go up to 120 decibels which is the same as a plane taking off. Sounds that loud can damage your ears.
80 decibels is thought to be the safe upper limit for listening to music. People who can't hear music at 80 decibels might need special noise-cancelling headphones.
Top tips to keep ears safe
- Use headphones at a sensible volume. Read any safety warnings that pop up on your music player.
- Stand away from speakers at shows and events.
- If you're going somewhere loud like a concert wear foam ear plugs to reduce the volume.
- If you are worried about your hearing or have ringing in your ears tell a parent or teacher.
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NIH offers online advice for older drivers
While many older people continue to drive safely into their 70s and beyond, age-related changes including declines in vision and hearing plus slower reaction times can impact driving ability. Certain health conditions and medications can also affect driving skills in older people, says the National Institutes of Health (NIH) and the National Highway Traffic Safety Administration (NHTSA).
To alert older people about how aging can affect driving abilities, the NIH recently added the topic "Older Drivers" to its NIHSeniorHealth online guide to health and wellness. Among other things, the new resource offer safety tips and suggestions about choosing the safest travel lanes, braking, making left turns and advice on adjusting driving habits to compensate for physical problems or health changes.
For complete information, visit www.nihseniorhealth.gov and click on Health Topics A-Z, then click on "O" for Older Drivers.
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We believe that textbooks should teach critical thinking. | About BJU Press
What is “Critical Thinking”?
Nearly everyone in educational circles uses the term “critical thinking”—in fact, it is so commonly used that it has become almost meaningless. Just what is critical thinking—and what is it not?
Let’s start with what it is not. Although many educators use test scores, grades, and fact-recall activities to gauge educational excellence, none of these truly measure critical-thinking skills. All education consists of two essential elements: subject matter (“what to think”) and the correct way to understand and evaluate the subject matter (“how to think”). Memorization is key to the first element. Critical thinking is key to the second.
In short, then, critical thinking is analyzing and evaluating thinking with the goal of improving it. According to the Foundation for Critical Thinking (found at criticalthinking.org), it is “that mode of thinking—about any subject, content, or problem—in which the thinker improves the quality of his or her thinking by skillfully analyzing, assessing, and reconstructing it.”
Thinking critically is thinking in order to evaluate. It means making reasoned judgments. It is using criteria to judge the quality of something. And its ultimate goal is further improvement of thinking skills.
Critical thinking goes hand-in-hand with creative thinking. Sound creative thinking requires both the intellectual discipline to judge and evaluate and the originality and productivity to create.
Why Should Christians Be Concerned with Thinking Critically?
The God of the Bible is a God of reason and order. God asks us to know truth (Ps. 46:10), but He also wants us to understand truth (Luke 24:45).
Both knowing and understanding are key. But beyond both knowledge and understanding, is the quality of discernment (judgment or evaluation) that distinguishes the godly from the ungodly (1 Cor. 2:14–15).
The Role of the Textbook in Teaching Critical Thinking
Of course, a textbook provides the factual base for studying a subject. But its worldview, its methods of teaching, its depth of content, and its literary quality should promote critical and creative thinking that is foundationally biblical.
Textbook content clearly plays an important role in what the teacher teaches, but the teacher’s edition of the textbook should offer help in promoting good thinking skills. That is why Teacher’s Editions from BJU Press provide you with key questions for discussion, discovery activities that complement your unique teaching style, and suggestions for writing (and other creative outlets) for using critical-thinking skills.
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The following glossary provides definitions for terms and descriptions for acronyms that are used in the AML Handbook. This glossary does not supersede definitions in relevant laws or regulations.
Abandoned Mine: An abandoned hardrock mine on or affecting public lands administered by the BLM, at which exploration, development, mining, reclamation, maintenance, and inspection of facilities and equipment, and other operations ceased as of January 1, 1981 (the effective date of the BLM’s Surface Management regulations codified at 43 CFR Subpart 3809) with no evidence demonstrating that the miner intends to resume mining. For many abandoned mines, no current claimant of record or viable potentially responsible party exists. Abandoned mines generally include a range of mining impacts, or features that may pose a threat to water quality, public safety, and/or the environment.
Abandoned Mine Land (AML) Program: A BLM program that focuses on reclaiming hardrock abandoned mine lands on or affecting public lands administered by the BLM. The primary goal of the program is to remediate and reduce actual or potential threats that pose physical safety risks and environmental degradation. The BLM applies risk-based criteria and uses the watershed approach to establish project priorities. The program also works to return mine-impacted lands to productive use(s).
Applicable and Relevant and Appropriate Requirements (ARARs): ARARs are State, local, and Federal standards that are directly applicable or may be considered relevant and appropriate to the circumstances on the site. ARARs include clean-up standards, standards of control, and other environmental protection requirements, criteria, or limitations. These standards are an inherent part of the scoping process, but will affect the long-term remediation, especially in the setting of clean-up standards and meeting other land use regulations.
Categorical Exclusion: A category of actions (identified in agency guidance) that do not individually or cumulatively have a significant effect on the human environment and for which neither an EA nor an EIS is required (40 CFR 1508.4).
Environmental and Disposal Liability (EDL): An anticipated future outflow or other sacrifice of resources (e.g., costs) associated with cleanup due to past or current operations that have environmental closure requirements or a release of hazardous substances, pollutants, and contaminants on BLM lands or facilities.
Geographic Information System (GIS): A computer system capable of storing, analyzing, and displaying data and describing places on the earth’s surface.
Government Performance and Results Act (GPRA): The GPRA (Pub.L. 103-62, Aug. 3, 1993, 107 Stat. 285) holds Federal agencies accountable for using resources wisely and achieving program results. GPRA requires agencies to develop plans for what they intend to accomplish, measure how well they are doing, make appropriate decisions based on the information they have gathered, and communicate information about their performance to Congress and to the public.
Hardrock: This term is used here strictly in the context of the AML program and has traditionally been used by the BLM and other agencies to apply to non-coal mining environments where environmental risks such as acid-mine drainage, heavy metal contamination, and threats to water quality and the environment are of concern. Hardrock minerals in this context, generally include, but are not limited to gold, silver, copper, lead, zinc, magnesium, nickel, molybdenum, tungsten, uranium, and select other minerals where priority AML problems may occur. Most hardrock minerals are locatable under the Mining Law of 1872. Non-hardrock minerals include coal (which is addressed by the Office of Surface Mining and State coal reclamation programs) and some common-variety mineral materials, such as sand and gravel.
Hazardous Substances: CERCLA term identifying those substances designated pursuant to section 1321(b)(2)(A) of Title 33, or 42 USC 9602, or listed in 40 CFR 302 or 355.
Hazardous Substance Release: Any spilling, leaking, pumping, pouring, emitting, emptying, discharging, injecting, escaping, leaching, dumping, or disposing into the environment (including the abandonment or discarding of barrels, containers, and other closed receptacles containing any hazardous substance or pollutant or contaminant).
Hazardous Waste: Refers to a solid waste, or combination of solid wastes, which because of its quantity, concentration, or physical, chemical, or infectious characteristics may pose a substantial threat to human health and the environment.
Mine: An underground opening or open pit used for the purpose of extracting minerals. Mines commonly include features, such as shafts, adits, pits, trenches, tunnels, waste rock dumps, tailings, and structures including, but not limited to, mills, buildings, head frames, hoists, and loading chutes.
Potentially Responsible Party (PRP): Any individual or entity, including current and past owners, operators, transporters, arrangers, or generators who may be liable for clean-up costs for hazardous substances under CERCLA Section 107(a) or for injuries to natural resources on public lands from hazardous substance releases under section 311(f) of the CWA and CERCLA section 107(f).
Project: The investigation, cleanup of safety risks, stabilization, or reclamation of an abandoned mine land site or sites. A project may include one or more individual abandoned mines. The project area may be based on geologic, geographic, hydrologic, watershed, ownership, or other legal boundaries, or based on practical or logistical convenience, and is often contiguous.
Remedial Action: Permanent remedy taken to prevent or minimize the release of hazardous substances into the environment. Long-term actions (5-8 years) are necessary to return a site to its original conditions.
Removal Action: Short-term actions necessary to remove or mitigate a release or threat of release of hazardous substances.
Site: The area identified as being impacted by physical safety and/or environmental hazards. This can include any area where hazardous substances have been released or have migrated. The area size is influenced by the extent of the investigation, migration, evaluation, and past, current, and future clean-up activities.
Special Status Species:
Includes proposed species, listed species, and candidate species under the ESA; State-listed species; and the BLM State Director- designated sensitive species (see BLM Manual 6840 - Special Status Species Management
Strategic Plan: A plan that establishes the overall direction for the BLM. This plan is guided by the requirements of GPRA, covers a 5-year period, and is updated every 3 years. It is consistent with FLPMA and other laws affecting the public lands.
Total Maximum Daily Load (TMDL): Pursuant to the Clean Water Act, an estimate of the total quantity of pollutants (from all sources: point, nonpoint, and natural) that may be allowed into waters without exceeding applicable water quality criteria.
Watershed: This term, when used generically, is the land area that drains water to a particular stream, river, or lake. It is a land feature that can be identified by tracing a line along the highest elevations between two areas on a map, often a ridge.
Watershed Approach: Refers to the methodology of working within the geographic boundaries of a watershed with partners (Federal, State, private, and Tribes) to jointly resolve problems that affect the physical, chemical, and biological quality of that watershed. A scientific approach is used to prioritize sites, develop clean-up action plans, and evaluate effectiveness of actions in the watershed. Partnering agencies and organizations share and exchange information, collaborate on project management, and reduce costs through fund leveraging and avoiding duplication of efforts and conflicting actions.
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Educator Resources for Treefrog Treasure
Treefrog Treasure is a platformer game that allows students to practice math concepts as they explore different worlds as a frog character. When certain obstacles are reached, students must properly identify a target symbol, whole number, or fraction on a number line to collect gems and complete the level. Hints are provided to help students reach the correct answer when mistakes are made. The game is a great differentiation tools, as it automatically adjusts to students’ performance to provide appropriate levels of mathematical complexity.
For teacher resources, visit Space Science Institute
In this lesson plan which is adaptable for grades 2-5, students will use BrainPOP resources and an online math game to explore fractions and match and/or compare fractional amounts.
Common Core State Standard Alignment:
CCSS.Math.Cont.3.NF.A.2a Represent a fraction 1/b on a number line diagram by defining the interval from 0 to 1 as the whole and partitioning it into b equal parts. Recognize that each part has size 1/b and that the endpoint of the part based at 0 locates the number 1/b on the number line.
CCSS.Math.Cont.3.NF.A.2b Represent a fraction a/b on a number line diagram by marking off a lengths 1/b from 0. Recognize that the resulting interval has size a/b and that its endpoint locates the number a/b on the number line.
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Children with low muscle tone often have delayed motor skills, muscle weakness, and / or coordination and balance problems. (Essentially the muscles lack stamina. The muscles don't have the energy to keep working at a normal level.) Children diagnosed with hypotonia can have varying degrees of severity of muscle weakness. For instance a child may seem to initially do everything just fine, but keep the same muscles working for any length of time and they will tire faster than a normal child's muscles. Muscle tone also comprises a second feature, which is the speed of the muscles' responses. The speed is slower in those with hypotonia. Due to the slower speed of the muscle response a child with hypotonia may have trouble keeping up with similarly aged children.
Hypotonia can occur in every muscle, so any movement that requires muscle activity and strength is likely to be impaired. Muscles are tied to every physical endeavor, from eating, to talking, our facial gestures, getting dressed, sitting, and walking. Our Physical Therapists provide an individualized evaluation and treatment program to improve a child's strength and overall function. If needed, our Physical Therapist can work in conjunction with our Occupational Therapist on Fine Motor/Upper Body Coordination and with our Speech and Language Therapist on delayed speech, Articulation, Oral Motor or any other Feeding/Swallowing Issues that a child my have.
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Surface area is a two-dimensional property of a three-dimensional figure. Cones are similar to pyramids, except they have a circular base instead of a polygonal base. Therefore, the surface area of a cone is equal to the sum of the circular base area and the lateral surface area, calculated by multiplying half of the circumference by the slant height. Related topics include pyramid and cylinder surface area.
If you want to calculate the surface area of a cone, you only need to know 2 dimensions. The first is the slant height l and the second is the radius. So what we're going to do, we're going to separate this into two pieces the first is the base which is a circle with radius r and the second is this slant height l. So if I cut, if I took a scissors and cut the cone part and I fended out it would look like a sector. Well what I could do here is I could rearrange this sector into a parallelogram. So again if I cut this into really tiny pieces then I'll be able to organize it into a parallelogram where I would be able to calculate its area. And the way that we'll calculate its area, is first by saying well what are these lines that are going out?
Well those lines are going to be your l, your slant height and this side right here is going to be half of your circumference and half of a circumference is pi times r because the whole circumference is 2 pi r. So this down here is pi times r, so if our height l and our base is pi times r then the area of this is equal to pi times r times l. So the surface area of a cone which I'm going to write over here is equal to the base pi r squared plus this lateral area which is found using your slant height. So that's going be pi times r times l, so you only need to know 2 dimensions the radius and the slant height and you can calculate the surface area of any cone.
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course through Hamburg
...the southeast of the old city, the Elbe divides itself into two branches, the Norderelbe and the Süderelbe, but these branches meet again opposite Altona, just west of the old city, to form the Unterelbe, which flows into the North Sea some 65 miles downstream from Hamburg. Two other rivers flow into the Elbe at Hamburg—the Alster from the north and the Bille from the east.
hydrology of Elbe River
The estuary proper of the Elbe (Unterelbe) extends from Hamburg to Cuxhaven, a distance of about 55 miles. It varies in width from one to two miles, but much of it is occupied by mud flats and sandbanks. The main channel is buoyed and dredged. At high tide the channel has a depth of some 53 feet (16 metres). The south or left bank is low and marshy and the river has sandbanks; the right bank is...
What made you want to look up "Unterelbe River"? Please share what surprised you most...
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William IIIArticle Free Pass
King of England
An invitation, signed by a representative selection of James’s opponents, was dispatched on July 10 (Old Style), and on November 5 (November 15, New Style) William and his army landed at Brixham on Tor Bay in Devon and proceeded almost unopposed to London. James fled to France, and the so-called Convention Parliament, summoned in January 1689, declared that James had abdicated and offered the vacant throne, with an accompanying Declaration of Right, to William and Mary. They were proclaimed in February and crowned on April 21. The crown of Scotland was offered to them in the same month.
The revolution in England had been accomplished almost without bloodshed, but in Scotland and Ireland there was armed resistance. This collapsed in Scotland in 1689, but the country remained troubled and unsettled throughout William’s reign. In 1692 Alexander MacDonald of Glen Coe and some of his clansmen were murdered in cold blood for tardiness in taking the oath of allegiance to William. William ordered an inquiry but took no further action until in 1695 the Scottish Parliament demanded a public investigation. He then showed culpable leniency to the offenders, merely dismissing from his secretaryship Sir John Dalrymple, on whom responsibility for the massacre was finally placed. In Ireland war formally broke out in 1689, when James landed there with French support. But the successful defense of Londonderry and of Enniskillen, and William’s own victory at the Battle of the Boyne on July 1, 1690, ensured the reconquest of Ireland and freed him to turn his attention to the European continent. Here, after a series of minor attacks on the empire, Louis XIV had invaded the Palatinate in 1688. The Dutch and the emperor concluded the Treaty of Vienna (May 1689) and declared war on Louis; over the next 18 months William’s rare diplomatic skill brought into the alliance Brandenburg, Hanover, Saxony, Bavaria, Savoy, and Spain, as well as England, which became its linchpin.
From 1691 William spent much time campaigning on the continent with varying degrees of success; but by 1696 a number of factors made both sides anxious for peace, and the Treaties of Rijswijk were signed in 1697. The question, vital for a European balance of power, of who was to succeed the childless king Charles II of Spain remained unsettled, however, and William had good cause to fear that the peace would be no more than a truce. The English Parliament, on the contrary, was convinced that it would be lasting, insisted on cutting down the size of the army, and resolutely turned its back on foreign affairs. William, in the hope of averting a new war, entered into two Spanish Partition treaties (1698–99) with Louis—measures that involved him in serious frictions with Parliament. But when the Spanish king died on Nov. 1, 1700, Louis, ignoring his agreements, accepted the crown of Spain for his grandson and soon showed that he had not relinquished his plans for French aggrandizement.
William, though hampered by English apathy, set himself to rebuilding the Grand Alliance and to preparing his two countries for the now inevitable conflict. In September 1701 the exiled James II died, and Louis XIV proclaimed his son king of England, contrary to his agreement in one of the Rijswijk treaties, and thus roused the English to an enthusiasm for war. William did not live to see this war declared. His health had long been declining, and in March 1702 he died. His plans for a European settlement were largely carried out by the Treaty of Utrecht (1713). His ideal, which he had pursued doggedly for 30 years, was an international order in which no single power was able to tyrannize the rest.
What made you want to look up "William III"? Please share what surprised you most...
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On the bicentennial of the War of 1812, What So Proudly We Hailed looks at this formative yet misunderstood period in American history through the lens of 21st century America. This provocative book asks, among other questions: What did America learn—and what did it not learn—from the experience? How did it help shape a nation?
With Congress divided along party lines, the U.S. government went to war without adequately preparing either the means to finance the conflict or the capabilities needed to achieve its aims. Like the United States two hundred years ago, the executive branch still suffers from in-fighting. The military invades a foreign nation, expecting to be treated as liberators. The entire endeavor winds down to a seemingly inconclusive ending. Sound familiar?
By 2003, America was waging two wars at once, at vast expense. Neither was financed by tax increases, but instead with borrowed money—much like in 1812, when the “Republican” party’s reluctance to use the government’s taxing power led to expanded debt and inadequate funding for the war effort.
In What So Proudly We Hailed, the contributors look at how Partisan animosity in 1812 surpassed today’s rancor, teaching us the danger of hyperpartisanship as well as the less obvious tendency of the party system to adapt and realign: The Federalist-Republican competition that dominated early U.S. politics dissipated in the war’s aftermath. We take today’s partisan divide as a given, but in time that too is likely to pass.
- Pulitzer-winning historian Alan Taylor (The Civil War of 1812) examines the war’s sectional tensions and the implications for American nationalism.
- Historian Peter J. Kastor discusses how 1812–15 affected state-federal relations.
- Author Stephen Budiansky (Perilous Fight) explores the military legacy.
- Pietro Nivola assesses the keen partisan rivalry of the early 1800s and what it can tell us about today’s strife.
- Benjamin Wittes and Ritika Singh of Brookings investigate constitutional frictions, particularly regarding presidential power and civil liberties.
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Focusing on Cancer Stem Cells
Many solid tumors appear to have a small population of stem cells that are partially resistant to chemotherapy and can perpetuate themselves indefinitely. These cancer stem cells thus far have been isolated from breast and brain tumors as well as blood. The exact origin of these cancer stem cells remains to be defined.
With mounting evidence to support the hypothesis that genetic alterations in tissue stem cells may represent the origins of some cancers, the time is right to more vigorously explore the properties, mechanisms, and vulnerabilities of this subset of cells. The presence of such cells, first demonstrated in acute myeloid leukemia patients, provides a different and exciting model with which to further explore cancer biology.
As a result, NCI is establishing a trans-NIH group of scientists interested in embryogenesis and cancer stem cell biology to advance the study of the underlying mechanisms in these processes. Establishing this group will facilitate the sharing of data, reagents, and animal models, and also provide a meaningful scientific interface with similar groups of extramural scientists.
Isolating and studying cancer stem cells should give us new insights into cancer and therapies. A defining characteristic of cancer stem cells is their ability to self-renew while giving rise to a diverse population of cells. In this respect, cancer stem cells are like embryonic stem cells, and the lessons of embryology, in which the role of stem cells are well defined, are crucial to understanding their role in carcinogenesis.
The mechanisms that allow controlled growth and migration of cells during the development of complex organisms from a single cell may be the same genetically programmed signal pathways that, when left unregulated in the adult organism, allow the development of tumors. Tumors are, in essence, complex "organs" complete with neovasculature and phenotypically altered supporting tissues.
Relatively little is known about the mechanisms of self-renewal, but researchers are beginning to identify potential genes and pathways involved. This could eventually lead to targets for intervening in the process, but without disrupting the behavior of normal tissue stem cells.
Some good news in this regard was reported last month. Researchers at the Dana-Farber Cancer Institute found differences between genetic signatures associated with self-renewal in cancer stem cells and in normal blood stem cells in mice. This suggests that it may be possible to target cancer stem cells in humans.
So where do cancer stem cells come from? One theory says they start out as normal stem cells until they become altered and start producing cancer cells. Another says that some more mature, differentiated cells may regain the ability to self-renew through genetic changes - a process of de-differentiation as they become malignant.
There may be evidence for both theories. It's important to remember that these rare cells have only recently been discovered. To answer fundamental questions about them, we need to develop more efficient techniques for isolating the cells and maintaining them in culture, and we need to draw on our knowledge of embryogenesis. Single-cell analyses will likely be needed to distinguish events present in cancer stem cells from the more differentiated cells that make up the majority of the tumor.
I am excited about the formation of this group. We have seen the success of another trans-NIH group in which NCI plays an integral role. The Trans-NIH Angiogenesis Research Program has improved the exchange of information and resources for angiogenesis researchers focused on diverse topics such as macular degeneration, cancer, and heart disease. Likewise, the new group has the potential to advance the science around stem cell biology and bring us closer to new and potentially highly effective therapies in cancer and other diseases.
Dr. John E. Niederhuber
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Garden Guide '10: The Right Tools
The Easy Bloom Plant Sensor shows which vegetables, fruits, herbs, flowers, trees, shrubs or houseplants will grow where, indoors or out.
There are so many different types of gardening tools available. How do you know which ones you'll really need?
For starters, you'll need something to dig with—shovel or a spade. A shovel is typically a scoop for mixing or moving material from one place to another. A spade is designed for digging. The blade is straighter than a shovel's and is made to be pushed into the soil.
Long-handle tools usually offer better leverage and reach and allow working from a standing position. The handle may be either straight or have a D-shaped grip. With some long-handle pruners, extensions may be available.
Short-handle tools are lighter, usually less expensive and more compact to store. They let you work in confined spaces or while kneeling. Common short-handled tools include hand pruners and clippers, hoes, garden trowels and cultivators.
Using short-handle tools means spending time low to the ground. A good, firm foam pad or strap-on kneepads can help prevent aches and pains. Choices range from simple pads to foldable seats.
Basic and not-so-basic tools
- Garden knives. Useful for cutting twine and plant ties and opening bags and plant root balls, the safer ones have non-collapsible fixed blades.
- Garden rakes. A heavy rake with short, stiff tines supported by a flat or bow-shaped metal frame is useful for raking heavy materials, removing rocks and other debris and smoothing the soil for planting.
- Leaf rakes. A light rake with long, thin, flexible tines designed to gather leaves or other light materials.
- Hand pruners and shears. Used for removing flowers, lightweight foliage and small branches.
- Hoes. For weeding and scraping the soil's surface, hoes include the traditional flat scraping or chopping types and the loop, scuffle and stirrup styles.
- Long-handled pruners and loppers. These long-handled versions of hand pruners provide greater reach and leverage, allowing for larger items to be cut.
- Mattocks. A heavy, flat-bladed tool designed to dig or grub in the soil on one end, with a sharp point to break up heavy or rocky soils on the other.
- Spading forks. Used to open up the ground, dig bulbs, incorporate soil amendments and turn compost, they have heavy, flat tines and often a D-shaped handle.
- Tillers. A power tool that breaks up large areas of compacted soil and incorporates soil amendments.
- Cultivators. A tool with heavy curved or bent tines or sometimes multiple spinning blades designed to open up and aerate the soil. Styles with tines are also used to mix materials and effectively loosen weed roots.
- The Weed Wrench, a manually-operated, all-steel tool designed to remove woody weeds by uprooting them.
- The Easy Bloom Plant Sensor shows which vegetables, fruits, herbs, flowers, trees, shrubs or houseplants will grow where, indoors or out.
Storing your tools
Avoid clutter and damage by keeping your tools organized and dry. There's a tremendous selection in stores and online of storage racks, systems, tool organizers, outdoor closets and sheds. A basic, simple storage idea is to use a bucket caddy with cloth pockets that wraps around a 5-gallon bucket. It's convenient for storing small tools and you can dump weeds in the bucket. Another idea for keeping small tools, seeds, sunscreen and other items handy is to mount a jumbo mailbox on a post near the garden.
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Strategic Plan - Disabilities & Disparities
Priority: Identifying and reducing disparities in key health indicators, including obesity, among children, youth and adults with disabilities.
What is the Problem?
- Obesity rates for children and adults with disabilities are 38 percent and 57 percent higher than rates for children and adults without disabilities.
- Adults with disabilities engage in physical activities on a regular basis approximately half as often as adults without disabilities (12 percent vs. 22 percent).
- Disparities have been found in access to health care, with 29 percent of people with disabilities showing unmet need compared to 12 percent of people without disabilities.
What Do We Know?
The growing body of research on the link between obesity and disability indicates that, for both children and adults, those at greatest risk for obesity have mobility limitations, intellectual/learning disabilities, or both. Whether obesity is the result of disability or a contributing factor to disability, children, youth and adults with disabilities are an important subgroup to address in reducing obesity in the United States.
Reasons for these disparities include:
- Lack of healthy food choices for many people with disabilities living in restrictive environments;
- Difficulty with chewing or swallowing food;
- Use of medications that can contribute to changes in weight and appetite;
- Physical limitations that can reduce a person’s ability to exercise;
- Pain and/or lack of energy;
- Lack of accessible environments such as sidewalks, parks, and exercise equipment; and
- Lack of resources such as money, transportation, and social support from family, friends, neighbors, and community members.
What Can We Do?
Now is the time for action. Evidence shows that regular physical activity and good nutrition provide improved cardiovascular and muscle fitness, enhanced mental health, and a better ability to perform tasks of daily life for people with disabilities.
We need: research to build the evidence for interventions; effective communication to inform stakeholders; and implementation of public health programs, policies, and practices to reduce the disparity in obesity and other health indicators such as health care access.
With our partners, we are integrating disability into national efforts that address obesity and other health conditions, and identifying and measuring outcomes for persons with disabilities to evaluate effectiveness and monitor change.
Learn more about disabilities
Learn more about NCBDDD’s strategic plan and priorities.
- Centers for Disease Control and Prevention
National Center on Birth Defects and Developmental Disabilities
1600 Clifton Road
Atlanta, GA 30333
TTY: (888) 232-6348
New Hours of Operation
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Asthma is a lifelong disease that causes wheezing, breathlessness, chest tightness, and coughing. It can limit a person's quality of life. While we don't know why asthma rates are rising, we do know that most people with asthma can control their symptoms and prevent asthma attacks by avoiding asthma triggers and correctly using prescribed medicines, such as inhaled corticosteroids.
The number of people diagnosed with asthma grew by 4.3 million from 2001 to 2009. From 2001 through 2009 asthma rates rose the most among black children, almost a 50% increase. Asthma was linked to 3,447 deaths (about 9 per day) in 2007. Asthma costs in the US grew from about $53 billion in 2002 to about $56 billion in 2007, about a 6% increase. Greater access to medical care is needed for the growing number of people with asthma.
Asthma is increasing every year in the US.
Too many people have asthma.
- The number of people with asthma continues to grow. One in 12 people (about 25 million, or 8% of the population) had asthma in 2009, compared with 1 in 14 (about 20 million, or 7%) in 2001.
- More than half (53%) of people with asthma had an asthma attack in 2008. More children (57%) than adults (51%) had an attack.
- 185 children and 3,262 adults died from asthma in 2007.
- About 1 in 10 children (10%) had asthma and 1 in 12 adults (8%) had asthma in 2009. Women were more likely than men and boys more likely than girls to have asthma.
- About 1 in 9 (11%) non-Hispanic blacks of all ages and about 1 in 6 (17%) of non-Hispanic black children had asthma in 2009, the highest rate among racial/ethnic groups.
- The greatest rise in asthma rates was among black children (almost a 50% increase) from 2001 through 2009.
Asthma Action Plan Stages
Green Zone: Doing Well
No cough, wheeze, chest tightness, or shortness of breath; can do all usual activities. Take prescribed longterm control medicine such as inhaled corticosteroids.
Yellow Zone: Getting Worse
Cough, wheeze, chest tightness, or shortness of breath; waking at night; can do some, but not all, usual activities. Add quick-relief medicine.
Red Zone: Medical Alert!
Very short of breath; quick-relief medicines don't help; cannot do usual activities; symptoms no better after 24 hours in Yellow Zone. Get medical help NOW.
Full Action Plan: http://www.cdc.gov/asthma/actionplan.html
Asthma has a high cost for individuals and the nation.
- Asthma cost the US about $3,300 per person with asthma each year from 2002 to 2007 in medical expenses.
- Medical expenses associated with asthma increased from $48.6 billion in 2002 to $50.1 billion in 2007. About 2 in 5 (40%) uninsured people with asthma could not afford their prescription medicines and about 1 in 9 (11%) insured people with asthma could not afford
their prescription medicines.
- More than half (59%) of children and one-third (33%) of adults who had an asthma attack missed school or work because of asthma in 2008. On average, in 2008 children missed 4 days of school and adults missed 5 days of work because of asthma.
Better asthma education is needed.
- People with asthma can prevent asthma attacks if they are taught to use inhaled corticosteroids and other prescribed daily long-term control medicines correctly and to avoid asthma triggers. Triggers can include tobacco smoke, mold, outdoor air pollution, and colds and flu.
- In 2008 less than half of people with asthma reported being taught how to avoid triggers. Almost half (48%) of adults who were taught how to avoid triggers did not follow most of this advice.
- Doctors and patients can better manage asthma by creating a personal asthma action plan that the patient follows.
Asthma by age and sex US, 2001-2009
Percentages are age-adjusted
SOURCE: National Center for Health Statistics; 2010.
Asthma self-management education by age, US, 2008
SOURCE: National Health Interview Survey, 2008, asthma supplement.
Adults with asthma in the US, 2009
SOURCE: Behavioral Risk Factor Surveillance System, 2009
Federal, state, and local health officials can:
- Track asthma rates and the effectiveness of control measures so continuous improvements can be made in prevention efforts.
- Promote influenza and pneumonia vaccination for people with asthma.
- Promote improvements in indoor air quality for people with asthma through measures such as smoke-free air laws and policies, healthy schools and workplaces, and improvements in outdoor air quality.
Health care providers can:
- Determine the severity of asthma and monitor how much control the patient has over it.
- Make an asthma action plan for patients. Use this to teach them how to use inhaled corticosteroids and other prescribed medicines correctly and how to avoid asthma triggers such as tobacco smoke, mold, pet dander, and outdoor air pollution.
- Prescribe inhaled corticosteroids for all patients with persistent asthma.
People with asthma and parents of children with asthma can:
- Receive ongoing appropriate medical care.
- Be empowered through education to manage their asthma and asthma attacks.
- Avoid asthma triggers at school, work, home, and outdoors. Parents of children with asthma should not smoke, or if they do, smoke only outdoors and not in their cars.
- Use inhaled corticosteroids and other prescribed medicines correctly.
Schools and school nurses can:
- Use student asthma action plans to guide use of inhaled corticosteroids and other prescribed asthma medicines correctly and to avoid asthma triggers.
- Make students' quick-relief inhalers readily available for them to use at school as needed.
- Take steps to fix indoor air quality problems like mold and outdoor air quality problems such as idling school buses.
Employers and insurers can:
- Promote healthy workplaces by reducing or eliminating known asthma triggers.
- Promote measures that prevent asthma attacks such as eliminating co-payments for inhaled corticosteroids and other prescribed medicines.
- Provide reimbursement for educational sessions conducted by clinicians, health educators, and other health professionals both within and outside of the clinical setting.
- Provide reimbursement for long-term control medicines, education, and services to reduce asthma triggers that are often not covered by health insurers.
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Announcements: World Stroke Day — October 29, 2012
Monday, October 29, is World Stroke Day 2012. Approximately 795,000 strokes occur annually in the United States. One of the leading causes of disability, stroke occurs among all age groups, including newborns, children, young adults, and older adults (1). One in six persons worldwide will have a stroke in his or her lifetime, and every 6 seconds someone will die from a stroke (2,3).
Although stroke is a common disease, it can be prevented. In addition, with timely care and support, most stroke survivors can recover and regain their quality of life. Everyone should take the following actions to reduce their likelihood of having a stroke: 1) know your personal risk factors, including high blood pressure, diabetes, obesity, high blood cholesterol, atrial fibrillation, and a history of having a transient ischemic attack or previous stroke; 2) engage in physical activity regularly; 3) maintain a healthy diet high in fruits and vegetables; 4) limit alcohol consumption; 5) avoid cigarette smoke (if you smoke, seek help to stop now); and 6) learn to recognize the warning signs of a stroke,* and call 9-1-1 right away if you think someone is having a stroke.
CDC addresses stroke prevention through state-based programs to prevent heart disease and stroke, through the Paul Coverdell National Acute Stroke Registry, and through many partnerships. Information on stroke prevention is available at http://www.cdc.gov/stroke, and additional information about World Stroke Day is available at http://www.worldstrokecampaign.org.
- Roger VL, Go AS, Lloyd-Jones DM, et al. Heart disease and stroke statistics–2012 update: a report from the American Heart Association. Circulation 2012;125:e2-e220.
- Seshadri S, Beiser A, Kelly-Hayes M. The lifetime risk of stroke: estimates from the Framingham Study. Stroke 2006;37:345–50.
- World Health Organization. The atlas of heart disease and stroke. Geneva, Switzerland: World Health Organization; 2004. Available at http://www.who.int/cardiovascular_diseases/resources/atlas. Accessed October 16, 2012.
* Sudden numbness or weakness of the face, arm, or leg, especially on one side of the body; sudden confusion, trouble speaking or understanding; sudden trouble seeing in one or both eyes; sudden trouble walking, dizziness, loss of balance or coordination; and sudden severe headache.
Use of trade names and commercial sources is for identification only and does not imply endorsement by the U.S. Department of
Health and Human Services.
All MMWR HTML versions of articles are electronic conversions from typeset documents.
This conversion might result in character translation or format errors in the HTML version.
Users are referred to the electronic PDF version (http://www.cdc.gov/mmwr)
and/or the original MMWR paper copy for printable versions of official text, figures, and tables.
An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S.
Government Printing Office (GPO), Washington, DC 20402-9371;
telephone: (202) 512-1800. Contact GPO for current prices.
**Questions or messages regarding errors in formatting should be addressed to [email protected].
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We seek the solution to the linear system of equations
Iterative methods, unlike direct methods, generate a sequence of approximate solutions to the system that (hopefully) converges to the exact solution. After k iterations, we obtain an approximation to the exact solution as:
where is the residual after k iterations.
as the difference between the exact and approaximate solution, we obtain
The purpose of iterations is to drive this residual to zero.
Stationary Iterative Methods
Iterative methods that can be expressed in the simple form
when neither B nor c depend upon the iteration count (k), the iterative method is called stationary iterative method. Some of the stationary iterative methods are
- Jacobi method
- Gauss-Seidel method
- Successive Overrelaxation (SOR) method and
- Symmetric Successive Overrelaxation (SSOR) method
The convergence of such iterative methods can be investigated using the Fixed point theorem.
Nonstationary Iterative Methods
When during the iterations B and c changes during the iterations, the method is called Nonstationary Iterative Method. Typically, constants B and c are computed by taking inner products of residuals or other vectors arising from the iterative method.
Some examples are:
- Conjugate Gradient Method (CG)
- MINRES and SYMMLQ
- Generalized Minimal Residual (GMRES)
- BiConjugate Gradient (BiCG)
- Quasi-Minimal Residual (QMR)
- Conjugate Gradient Squared Method (CGS)
- BiConjugate Gradient Stabilized (Bi-CGSTAB)
- Chebyshev Iteration
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Could the Pap smear, which is already commonly used to detect cervical cancer, also be used to find endometrial and ovarian cancers? A small study suggests that may be possible in the future.
Scientists at Johns Hopkins have found that cervical fluid collected during a routine Pap smear can be used to detect both types of cancers by using a genome sequencing test called the "PapGene."
Researchers administered the test on a small group of samplings, and found the procedure accurately detected all 24 endometrial cancers, or cancer of the lining of the uterus. However, they were only able to find nine of 22, or 41%. of ovarian cancers.
According to the American Cancer Society, only 20% of ovarian cancers are found early. Survival chances increase dramatically when cancers are caught early, before they have spread.
The Pap test is designed to collect cervical cells that are examined for cancer. It is the gold standard for cervical cancer screening. Yet, there is no good screening method available for ovarian or endometrial cancers.
Because the pilot study was small, investigators say this genetic test is not ready for general practice. They emphasize larger studies still need to be conducted and the test may even have to be refined, particularly to improve finding ovarian cancers. Scientists involved in the initial research are already recruiting patients for the next trial phase.
But doctors are still excited, especially since the test would be easy and convenient since the Pap test is already available. When cells are taken in a Pap test, there is excess fluid that accumulates on the smear. Those are the fluids the test would examine for the other cancers.
And investigators say the procedure would eliminate a lot of "false positive" results that previous tests for these cancers have caused.
"The lack of false positives is a real advantage, because they often lead to anxiety and worry in the patient," says Dr. Luis Diaz, the lead investigator of the study and an associate professor of oncology at Johns Hopkins. "And the follow-up tests are expensive and can be invasive. We are hoping this test will take away those worries."
Results of the experiments are published in the January 9 issue of the journal Science Translational Medicine.
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Hydrates are crystalline solid compounds formed from water and smaller molecules in hydrocarbon fluids such as methane, ethane, propane, nitrogen, carbon dioxide and hydrogen sulfide.
Hydrates are a nuisance, since they can block pipelines leading to stoppage of pipeline transportation operations and hence are an important aspect of pipeline flow assurance that needs to be addressed.
Hydrate formation in pipeline requires three conditions to exist:
1. The right combination of temperature and pressure. Hydrate formation is favored by low temperature
and high pressure.
2. A hydrate former must be present. Hydrate formers are the hydrocarbons mentioned as above.
3. A sufficient amount of water – not too much, not too little.
Certain other conditions in the pipeline enhance the formation of hydrates and are listed below:
This can be either due to high velocity or agitation of the process fluid. High velocities in pipelines
can occur at any sudden restrictions in the line such as a choke valve. In gas flow a large pressure
drop across the choke valve causes the temperature to drop due to the Joule-Thomson effect which
favors hydrate formation
B. Nucleation Sites:
In general terms, a nucleation site is a point where a phase transition is favored, and in this case the
formation of a solid from a fluid phase.
Good nucleation sites for hydrate formation include an imperfection in the pipeline, a weld spot, or a
pipeline fitting (elbow, tee, valve, etc.). Silt, scale, dirt, and sand all make good nucleation sites as
C. Free Water:
Free-water is not necessary for hydrate formation, but the presence of free-water certainly enhances
“HYSYS” has a utility called “Hydrate Formation Utility” which predicts the hydrate formation temperature of any defined stream for a given stream pressure and the hydrate formation pressure for a given stream temperature. Most process engineers having access to “HYSYS” would find it convenient to use this utility to determine hydrate forming conditions.
In addition to “HYSYS” an old DOS based program with the name “CSMHyd” developed by the “Colorado School of Mines” also predicts the hydrate formation pressure for a given temperature. This program is available for free download at:
In addition to "HYSYS" and "CSMHyd", I had done some of my own investigation and compilation on the subject of hydrate formation conditions in natural gas. The focus of this investigation was to find out whether there were some empirical methods to determine the “hydrate formation temperature” given only the natural gas pressure and the molecular weight / specific gravity of the gas. My investigation was successful considering that I found not one but several empirical methods to determine the “hydrate formation temperature” given only the natural gas pressure and the specific gravity or molecular weight of the gas.
An important point to note is that while both “HYSYS” and “CSMHyd” require that the gas composition be known, whereas the empirical methods I investigated do not require natural gas composition as such. Just the natural gas molecular weight or the natural gas specific gravity allow the determination of the “hydrate formation temperature”.
The end result of this detailed investigation resulted in the generation of an excel workbook where these empirical methods have been represented with example calculations. This blog entry shares the excel workbook.
Download the MS Excel Spreadsheet here
Any comments and observations would be welcomed from the readers and members of “Cheresources”.
References for the hydrate formation mechanism are as follows:
Natural Gas Hydrates – A Guide for Engineers by John Carroll
Section 20- GPSA Engineering Data Book, 11th Ed.
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In On Becoming Childwise, the authors urge us to parent all four general capacities of our children. The four general capacities are as follows:
1. Physical. It is our duty to nurture and provide for our children’s physical growth and well-being. This includes not only basic food, clothing and shelter, but also healthy eating habits, regular exercise, good hygiene, and all other things related to their little bodies.
2. Intellectual. The authors say that we are required to provide “basic skills, logic, and useful knowledge.” But I would extend this to say that we need to determine how our children learn best. Whether our kids are educated in preschool, private school, public school or homeschool, we need to do more than simply accept the cultural norm. Find the education solution that works best for the individual child (within the context of the family situation, of course).
3. Emotional. I’m a little troubled by what the book says in regard to this capacity: “Parents help their children establish internal controls over both positive and negative emotions,” (p. 66). Maybe I’m misreading it, but it sounds to me like they’re saying our children need to learn to suppress their emotions. I think parenting our children’s emotional capacity is all about accepting our children’s emotions, no matter what. If my child is physically hurt, I’m going to let him cry. Or if a friend intentionally excludes my child in play, I’m going to acknowledge the sadness that it caused. It’s all about showing that emotions are a normal, acceptable part of life. Parenting in this area is also about showing patience and empathy for others. This can be done through modeling this for them, teaching through direct instruction, and correcting behaviors that go against this goal.
4. Moral. I wholeheartedly agree with this statement: “The duty of a parent is to help his or her child internalize virtues that reflect the values of the family and society,” (p. 66).
But ultimately, no matter how we address each area of parenting, we must find a balanced approach. There are some kids who may need more attention in one capacity than another, but we must still address all areas. To spend all of our time and effort helping the child’s intellectual growth while neglecting any moral teachings represents unhealthy, unbalanced parenting. The same holds true for focusing on moral teachings over emotional attention.
The book sums it up nicely:
“All four facets receive attention. None should be neglected, underdeveloped, or overemphasized. Why is that? Because competence and character go hand in hand. You do not want to raise a smart child who lacks integrity. Nor do you want a great athlete with a shallow intellect. Academic skills without values, values without healthy emotions, happy feelings without productivity, and physical stature without moral wisdom all represent developmental imbalances,” (p. 66).
Stop for a minute to think about how balanced your parenting may be. Do you tend to favor one capacity over another? Does your child require more attention in one area than another? If so, are you able to balance out the other areas? Is any imbalance caused by you, society around you, urgings from family members or friends? If so, don’t be afraid to go against the grain and stand up for a whole child parenting approach.
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Paroxysmal supraventricular tachycardia (PSVT)Definition:
Paroxysmal supraventricular tachycardia (PSVT) is episodes of rapid heart rate that start in a part of the heart above the ventricles. "Paroxysmal" means from time to time.
PSVT; Supraventricular tachycardia
Causes, incidence, and risk factors:
Normally, the chambers of the heart (atria and ventricles) contract in a coordinated manner.
- The contractions are caused by an electrical signal that begins in an area of the heart called the sinoatrial node (also called the sinus node or SA node).
- The signal moves through the upper heart chambers (the atria) and tells the atria to contract.
- After this, the signal moves down in the heart and tells the lower chambers (the ventricles) to contract.
The rapid heart rate from PSVT may start with events that take place in many different areas above the lower heart chambers (ventricles).
PSVT can occur with digitalis toxicity and with conditions such as Wolff-Parkinson-White syndrome .
The condition occurs most often in young people and infants.
The following increase your risk for PSVT:
Symptoms usually start and stop suddenly, and can last for a few minutes or several hours. They can include:
Other symptoms that can occur with this condition:
Signs and tests:
A physical examination during a PSVT episode will show a rapid heart rate. It may also show bounding pulses in the neck.
The heart rate may be over 100, and even more than 250 beats per minute (bpm). In children, the heart rate tends to be very high. There may be signs of poor blood circulation such as light-headedness. Between episodes of PSVT, the heart rate is normal (60 to 100 bpm).
An ECG during symptoms shows PSVT. An electrophysiology study (EPS) may be needed for an accurate diagnosis and to recommend the best treatment.
Because PSVT comes and goes, to diagnose it patients may need to wear a 24-hour Holter monitor . For longer periods of time, another tape of the rhythm recording device may be used.
If you do not have symptoms or any other heart condition, PSVT may not need treatment.
If you have an episode of PSVT, there are techniques you can try on your own to interrupt the fast heartbeat.
- One is called the Valsalva maneuver. To do this, you hold your breath and strain, as if you were trying to have a bowel movement.
- Another technique you can try is to cough while sitting with your upper body bent forward.
- Some people find that splashing ice water on the face is helpful.
You should avoid smoking, caffeine, alcohol, and illicit drugs.
Emergency treatment to slow the heartbeat back to normal may include:
- Electrical cardioversion , the use of electric shock
- Medicines through a vein
Long-term treatment for people who have repeat episodes of PSVT, or who also have heart disease, may include:
Cardiac ablation -- a procedure used to destroy small areas in your heart that may be causing the rapid heartbeat (currently the treatment of choice for most PSVTs)
- Daily medications to prevent repeat episodes
Pacemakers to override the fast heartbeat (on occasion may be used in children with PSVT who have not responded to any other treatment)
- Surgery to change the pathways in the heart that send electrical signals (this may be recommended in some cases for people who need other heart surgery)
PSVT is generally not life threatening. If other heart disorders are present, it can lead to congestive heart failure or angina.
Calling your health care provider:
Call your health care provider if:
- You often have a sensation of feeling the heart beat quickly and symptoms do not end on their own in a few minutes
- You have a history of PSVT and an episode does not go away with the Valsalva maneuver or by coughing, or other symptoms occur with the rapid heart rate
- Symptoms return often
- New symptoms develop
Olgin JE, Zipes DP. Specific arrhythmias: diagnosis and treatment. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. St. Louis, Mo: WB Saunders; 2011:chap 39.
Zimetbaum P. Cardiac arrhythmia with supraventricular origin. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 64.
|Review Date: 6/18/2012|
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Michael A. Chen, MD, PhD, Assistant Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, Washington. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997-
A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
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|Curiosity about fire is normal, but playing with fire is dangerous. Whether it is the result of a curious child or the intentional setting of a fire by a troubled teen, juvenile firesetting is a serious problem that may escalate. By recognizing the problem early and taking corrective measures the risk of fire setting incidents can be greatly reduced.
WHY DO KIDS SET FIRES?
Most children express a natural and normal curiosity about fire in their early life. Their interest can be expressed in a number of appropriate ways: asking fire related questions, playing with fire related toys such as a fire engine and for older children, participating in adult supervised activities involving fire, such as lighting a BBQ or fireplace. When a child’s interest and experimentation with fire are unsupervised, the potential for disaster exists.
Some children however, set fires deliberately. Reason for this may include: peer pressure, boredom, anger, a cry for help, or a significant crisis such as a divorce or death of a family member. For these children, fire setting can become an outlet for their feeling and require intervention.
- Arson is the leading crime committed by kids and it is the fastest growing crime in the U.S.
- Over 55% of all arrests for arson are kids & ½ of those are 4-9 years old.
- Fire is the leading cause of accidental death in the home for kids 5 & under; many are the victims of fires set by an older sibling.
WHAT CAN PARENTS DO TO PREVENT FIRE SETTING?
Supervise for safety
Provide appropriate and effective supervision for children. Supervision requires frequent visual contact so that children’s activities can be monitored. Supervision also includes previewing what children are watching on TV, DVD, and the internet. Restricting access to some internet sites is recommended.
Remove the temptation
Keep matches and lighters out of reach of kids. Better yet, remove all unnecessary matches and lighters from your home. Most children are only involved with fire because it is available. Remember, child resistant lighters are not childproof, not even for a 2 year old.
Teach children about fire
Teach young children that fire is a tool used to heat our homes and cook our food – it is not a toy! Fire is not magic; it is hot and can cause devastating consequences.
Teach match and lighter safety
Matches and lighters are tools for grown-up NOT toys for children. If children find matchers and lighters, young children (under the age of seven) should TELL & SHOW a grown-up, and children older than seven should GIVE them to a grown-up.
Older children 12 and up should be taught the safe and responsible use of matches and lighters, under direct adult supervision. These children can be provided with an opportunity to light the fireplace, campfire or candles on a birthday cake. Always reward or praise children for demonstrating fire safe behavior.
Set a good example
Children don’t always hear what you say, but they certainly see what you do. Young children learn by exploring, experimenting and mimicking adult behavior. Model fire safe behavior in your home at all times.
WHAT DO YOU KNOW ABOUT THE MYTHS & REALITIES OF FIRE?
MYTH: It is normal for children to play with fire.
FACT: While curiosity about fire is common, playing with fire and setting fires is not normal and can be deadly.
MYTH: Fire setting is a phase children will outgrow.
FACT: It is NOT a phase. You must deal with it immediately or it will continue and progress.
MYTH: If the fire is small there is no problem.
FACT: All fires start small. However, fires spread quickly and can easily get out of control, endangering lives and property.
MYTH: Children who start fires are pyromaniacs.
FACT: Almost every child has some curiosity about fire. But progression from mere interest in fire to fire setting is a problem. Occasionally fire setting can be a symptom of a more widespread problem.
WHAT SHOULD YOU DO IF YOU KNOW A CHILD WHO NEEDS HELP?
- Keep all lighting materials out of reach – lock them up!
- Make sure the child is appropriately supervised.
- Install smoke alarms throughout your home, including in the bedrooms.
- Get help from Hillsboro Fire Department. Call 503-681-6166 to set up an appointment with our Juvenile Firesetter Interventionist. We provide early intervention that evaluates, educates, and refers kids & families to services to stop firesetting behaviors.
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Last August, a 3,000-pound, eight-by-22 foot-robotic platform was launched into the Hudson River just north of Denning’s Point Peninsula in Beacon, N.Y.
On board the floating platform are state-of-the-art sensors that will provide continuous air and water monitoring including barometric pressure, wind speed and direction, water depth, temperature, salinity and flow rate. The sensors will also measure the levels of hydrogen contaminants, dissolved oxygen, and chlorophyll-a (a green pigment found in algae). The data will be transferred in real time to researchers who can track fluctuations in these measurements.
The information provides a detailed record of the overall health of the river. This will alert scientists and environmentalists to escalating pollution levels or to episodic events that can be problematic, such as algae blooms, which can lead to hypoxia. Hypoxia is characterized by a low concentration of oxygen that is exacerbated by increases in nutrients or a particular set of physical conditions. It is associated with fish kills among other problems.
This technology, which promises to revolutionize the way bodies of water are monitored, was developed by a team of scientists and researchers headed up by James Bonner ’85, professor of civil & environmental engineering and director of Clarkson’s Center for the Environment (CCE).
“Our goal is to eventually cover the entire 315-mile river from Mt. Marcy to New York City with a network of sensors,” explains Bonner. “The technology will allow us to create a cyber-infrastructure that stores and processes a great deal of data about the Hudson River. Scientists and engineers around the world will be able to access this information via the Internet.”
Bonner began the development of this real-time monitoring technology at the Shoreline Environmental Research Facility at Texas A&M University where he served as founding director. While in Corpus Christi, Bonner and fellow researchers developed sensing systems that they used to monitor the Gulf of Mexico. Since joining the Clarkson faculty in 2007, Bonner (who holds a Ph.D. from Clarkson) has continued his NSF-funded research program with an eye toward transferring the technology to map and monitor the ecological health of the rivers, Great Lakes and the St. Lawrence Seaway.
The Hudson River monitoring project is a joint partnership between Clarkson University; the Beacon Institute for Rivers and Estuaries, a not-for-profit environmental research organization; and IBM. Last year, Bonner was named the Beacon Institute’s REON Director of Research and will lead the development and implementation of the River and Estuary Observatory Network (REON). The Hudson River project is the first step in a larger plan to develop technology-based monitoring and forecasting network for rivers and estuaries.
“Tremendous human impact occurs in the regions where rivers and estuaries meet the ‘coastal margin’ — coastal wetlands, bays and shorelines,” explains Bonner. “In the United States, this region is home to 70 percent of the population and 20 of its 25 largest cities. It is also where most industry and ports are found. Damage to these ecosystems comes from this increased density of anthropogenic activity associated with pollution from industry, farms and the surrounding communities.”
For example, hypoxia generally occurs in aquatic systems where the water is poorly mixed excluding oxygen and trapping pollutants in the “hypolimion” — the dense bottom layer in a stratified body of water. Chemical reactions within the hypolimion and with bottom sediments depletes the benthic oxygen so aerobic organisms such as fish, oysters, clams and other bottom dwelling organisms perish. “This problem is a growing national concern, for example increasing areas of the Gulf of Mexico (thousands of square miles), portions of the Great Lakes, embayments such Corpus Christi Bay and other near-shore areas are experiencing hypoxia,” says Bonner.
IBM is working with Bonner and the Beacon Institute to develop the cyber framework that will store the data and provide assessment tools, which researchers around the world will be able to use. “Scientists will be able to analyze data and develop models on any environmental parameter of interest.”
For Bonner, one of the most exciting aspects of the project is the way it will transform environmental science and engineering. “The old-fashioned method of retrieving data by collecting samples at discreet locations at only a few times gives a static, incomplete and aliased view or understanding. With this technology, we’ll be able to get real-time data that reflects the constantly changing, dynamic environment of the river. The information will be far more reliable.”
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February 24, 2013 in Sustainable Development
EMBARGOED until 1800 GMT on Sunday 24 February
By Alex Kirby
A United Nations scheme intended to guarantee everyone access to clean energy could help to keep global temperature rise below 2°C, researchers say, although it would not achieve this without sharp cuts in emissions of all the main greenhouse gases.
LONDON, 24 February – Eradicating poverty by making modern energy supplies available to everyone is not only compatible with measures to slow climate change, a new study says. It is a necessary condition for it.
But the authors say the scheme to provide sustainable energy worldwide will not by itself be enough to keep the global average temperature rise below the widely accepted international target level of 2°C. While the scheme can help measures to tackle climate change, it cannot achieve that by itself.
The scheme, the UN’s Sustainable Energy for All initiative (SE4All), if it proves successful, could make a significant contribution to cutting greenhouse gas emissions, according to the analysis from the International Institute for Applied Systems Analysis (IIASA) and ETH Zurich.
The study, published in Nature Climate Change, shows that reaching the three energy-related goals of SE4All would cut GHG emissions and is achievable.
“Achievement of the three objectives would provide an important entry point into stringent climate protection”, says Joeri Rogelj, ETH Zurich researcher and IIASA-affiliated scientist, who led the study.
It found that the short-term goals, due to be reached by 2030, would help achieve long-term climate targets. But to ensure stringent climate objectives were reached, SE4ALL would need to be matched by other measures, the researchers say.
SE4All ‘necessary – but not sufficient’
SE4All’s objectives include providing universal access to modern energy, doubling the share of renewable energy globally, and doubling the rate of improvement in energy efficiency – all by 2030.
While the objectives do not explicitly address climate change, sustainable energy is accepted as vital for cutting GHG emissions: 80% of CO2 from human activities comes from the global energy system, including transport, buildings, industry, and electricity, heat, and fuel production.
“Doing energy right will promote the Millennium Development Goals and at the same time kick-start the transition to a lower-carbon economy”, says IIASA researcher David McCollum, who also worked on the study. “But the UN’s objectives must be complemented by a global agreement on controlling GHG emissions.”
SE4All has global goals, but the researchers say action at regional and national levels will be essential to achieving them. IIASA’s energy programme leader Keywan Riahi, a co-author of the study, says: “The next step for this initiative is already under way, with a large number of national plans that underpin the global objectives.”
They analysed the likelihood of the world limiting global warming to target levels if each or all of the SE4All objectives were achieved. Using a broad range of scenarios, they found that if all the objectives are met, the likelihood of keeping temperature rise below 2°C will be more than 66%.
If only the renewable energy goal is met, chances of staying below 2°C will range from 40 to 90%, they say, while achieving just the energy efficiency goal will improve the chances to between 60 and 90%.
But the researchers warn that this result depends strongly on what future economic growth is assumed. They say the likelihood of reaching climate targets within the scenarios depend on a range of other factors, including energy demand growth, economic growth, and technological innovation.
The study also found that providing universal energy access by 2030 will not hinder long-term climate goals, thanks to the marked gains in energy efficiency that will result. “Sustainable development and poverty eradication can go hand in hand with mitigating climate risks,” says Rogelj.
He told the Climate News Network: “To ensure effective climate change mitigation, a global treaty on greenhouse gases should enforce a cap on global emissions which limits emissions from all sources.
“With such a cap SE4ALL can help to limit emissions from the energy sector, but other measures will have to tackle those from other sources like deforestation, or other gases, like methane from agriculture and waste, or facilitate an even quicker decarbonization of the energy sector, like carbon-capture and storage.”
The new work also quantified the potential costs of reaching the SE4All objectives, which would amount to increasing energy investment by between 0.1 and 0.7% of global GDP. The authors’ estimates account for the substantial savings in energy use and reduced fossil energy investment that would result from promoting more sustainable energy technologies and lifestyles. – Climate News Network
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According to a team of scientists at Australia’s Commonwealth Scientific and Industrial Research Organisation, despite previous research finding that nanoparticles do not penetrate the skin, it remains debatable as to whether this remains true under normal conditions of using sunscreen.
At a Global Nanomaterials Safety workshop in London earlier this month, Dr Maxine McCall showcased her team’s progress on ‘Dermal absorption from sunscreens containing zinc oxide particles’ revealing that two special sunscreens were made especially for a human study whereby one contained nanoparticles of zinc oxide and the other larger (non-nano) particles to determine if there was a dependence on particle size for dermal absorption.
According to Dr. McCall, most in vitro studies to assess dermal penetration of nanoparticles are conducted for a period of up to 24 hours, and that the OECD WPMN is currently assessing whether a number of test guidelines, developed for chemicals, are applicable to nanomaterials.
“Our results imply that longer study periods may need to be considered when assessing dermal penetration and absorption of nanoparticles and we are communicating this information to the OECD WPMN,” the expert told CosmeticsDesign-Asia.com.
The human study involved the team of scientists applying sunscreen twice daily for five days as well as obtaining numerous blood and urine samples before, during, and after the period at the beach.
"The method we used to detect the traceable zinc is highly sensitive," explains McCall.
"The first detection of traceable zinc from ZnO particles in the sunscreens were found in the blood at the end of the second day at the beach and after a total of 4 sunscreen applications, levels continued to increase after sunscreen application ceased," she adds.
The expert went on to further reveal that the blood and urine samples from the females with the sunscreen with nanoparticles had slightly higher levels of traceable zinc than those of the sunscreen with larger particles.
However, Dr. McCall concludes by informing this publication that the total amounts of traceable zinc detected from the sunscreens were very small when compared with amounts of natural zinc normally present in the human body.
SCCS view on the matter..
The EC's Scientific Committee on Consumer Safety recently announced it had reviewed its toxicological evidence and found no evidence that ZnO nanoparticles are absorbed through skin and or via the oral route.
And concluded that the use of zinc oxide nanoparticles, at a concentration up to 25 percent as a UV-filter in sunscreens, “can be considered not to pose a risk of adverse effects in humans after dermal application."
However, it did note that this did not apply to other applications that might lead to inhalation exposure to zinc oxide nanoparticles, such as sprayable products.
“In view of the lung inflammation induced by ZnO particles after inhalation exposure, the use of ZnO in cosmetic products which may result in inhalation, is of concern.”
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I saw some tutorial pages on the internet about how to read files using C++
But I'm kind of confused because there isn't anything in code indicate where the file is from. So I think I need some explanation.
It will open file in current (working) folder. If you want to open file which is in another folder you may write full path: ofstream ofs("C:\\some_folder\\some_file");
There is version of the constructor (and open() function) which takes std::string, if you use them.
What you pass is actually the file path, so you can give a full path, or a relative path. If you just specify the filename that is a relative path. Relative paths are relative to the working directory of program. If you start your program by double clicking on the executable file the working directory will be the directory where the executable file is located. If you start your program from the command line the working directory will be the directory that you set using the cd command. If you start your program from an IDE the working directory is often set to the project directory (not the source directory) but this can differ between IDEs.
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Use the Activities
Putting It All Together
All the events prior to and during the American Revolutionary War in central New York are interrelated, and these had profound effects on the people who lived there. In these activities, students will compare their lives in their community to what it would be like to live in central New York during this time. Students will also explore what it was like to be at the Battle of Oriskany.
Activity 1: Where Do I Stand?
Ask each student to select one of the historical people who participated at the Battle of Oriskany and create a report in the character of that person about the experience.
The report may be written or oral. Once the student has identified what person they are portraying and explained why that character was selected, the student should answer the following questions in character:
1. What do you (the person you are roleplaying) believe in? What do you support?
2. What do you oppose?
3. What are your hopes and dreams?
4. What are you feeling before this battle? Are you angry, sad, happy or a mixture of these? Are you worried or anxious about yourself and your family? Are you optimistic or pessimistic about the outcome of the battle?
5. Place yourself in the battle. Where are you located, in the ravine or on the hilltop? What do you see, hear, smell and feel? Who do you see? What are you doing? What are your feelings? Are you afraid, angry, or confused or a mixture?
6. After the battle, how do you feel? Are you worried or anxious about your family? What do you see in your immediate or long-term future? Has your outlook changed? Have your hopes and ambitions changed? Are you optimistic or pessimistic about the future?
Activity 2: The Lost Battlefield
The Oriskany Battlefield has been lost over time. The land is still there, however, the old Military Road is gone, the virgin woodland forest has been clear cut, and exact placements of everyone on the battlefield can not be reproduced. Except for letter and journal entries, some written shortly after the battle and others collected long after the battle (which sometimes are conflicting) there is little to tell us exactly where and how the battle was fought. There is also little physical evidence available to help researchers evaluate the reliability of these accounts.
Students are going to be asked to recreate the Battle of Oriskany. They should keep a written journal or recorded oral log about the investigative and production phases of the project. After students have completed studying the quotes in the readings, looked at maps of the area or colonial illustrations depicting military clothing and weapons, and completed additional personal research, ask them to complete one of the following activities:
1. As an historical cartographer, find the ravine and high ground, and then draw a map or series of maps of Oriskany battlefield during the battle's different phases.
2. As an historical illustrator, sketch or paint a picture or series of pictures of the Battle of Oriskany.
3. As a re-enactor or documentary film-maker, create costumes, re-enact the
battle, and videotape the re-enactment. Edit the tape and add voice-over
narration for final presentation.
Activity 3: In the Grip of Fear
Ask the students to produce a written, pictorial, or video report describing a controversial issue which has divided their community. Point out that community can be interpreted in many ways and may be their school, sports teams, parent groups, school board, local government, or state government as well as the nation or world. The students will have to use investigative research techniques and questioning strategies to find the answers through review of local newspapers, committee reports, and personal interviews. Students may want to record their data on a chart like the one used in Reading 1. Ask them to identify what the controversy is, and then answer the following questions:
1. Is there only one central issue that is causing the controversy, or are there several issues?
2. What was the history of the community before the controversy? Are there events in the past which affect the issue(s) today?
3. Who are the key leaders on both sides of the issue? Why have they taken the stand they have taken?
4. What is the general social make-up of the followers of these leaders? Where are they from? In which part of the community do they live? What is their social, political and economic standing? What are their race, ethnicity, and sex? What types of jobs do they have? Where do they stand on the issue and why?
After the students have completed this activity, have them ask the same questions about the Mohawk Valley civil war and then compare and contrast the contemporary controversy they have studied with the Mohawk Valley civil war. Alternatively, the students may want to compare the controversy they have studied with the U.S. Civil War, regional civil wars in the U.S. (such as in "Bleeding Kansas"), or civil wars on the international scene (such as in Rwanda and Kosovo in the 1990s or China in the 1940s).
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Wikipedia: Paul the Apostle
Paul the Apostle (Greek: Παῦλος Paulos), original name Saul of Tarsus (Greek: Σαῦλος Saulos), was a Christian missionary who took the gospel of Christ to the first-century world. He is generally considered one of the most important figures of the Apostolic Age and one of the greatest religious leaders of all time. In the mid-30s to the mid-50s, he founded several churches in Asia Minor and Europe. Being a Jew and a Roman citizen were ideal pedigrees for his ministry to both Jewish and Roman audiences.
A native of Tarsus, the capital city in the Roman province of Cilicia, he wrote that he was "a Hebrew born of Hebrews", a Pharisee, and one who advanced in Judaism beyond many of his peers. He zealously persecuted the early followers of Jesus and violently tried to destroy the newly-forming Christian church. Paul's dramatic conversion experience with the risen Jesus on the road to Damascus dramatically changed the course of his life. He did not know Jesus during his lifetime as did the Twelve Apostles, but he was the first apostle whose only experience with Jesus was after the Resurrection and Ascension.
After his conversion to Christ, he began to preach that Jesus of Nazareth is the Messiah and the Son of God. His leadership, influence, and legacy led to the formation of communities dominated by Gentile groups that worshiped the Lord, adhered to the "Judaic moral code", but relaxed or abandoned the ritual and dietary teachings of the Law of Moses. He taught that these laws and rituals had either been fulfilled in the life of Christ or were symbolic precursors of Christ, though the exact relationship between Paul the Apostle and Judaism is still disputed. Paul taught of the life and works of Jesus Christ and his teaching of a New Covenant, or "new testament", established through Jesus' death and resurrection.
About half of the New Testament stems from Paul and the people whom he influenced. Thirteen of the 27 books in the New Testament have been attributed to Paul, and approximately half of the Acts of the Apostles deals with Paul’s life and works. However, only 7 of the 13 letters can be accepted as being entirely authentic. The other 6 letters are believed to have come from followers writing in his name, using material from Paul's surviving letters and letters written by him that no longer survive.
Today, his epistles continue to be deeply rooted in the theology, worship, and pastoral life in the Roman and Protestant traditions of the West, as well as the Orthodox traditions of the East. Among the many other apostles and missionaries involved in the spread of the Christian faith, his influence on Christian thought and practice has been characterized as being as "profound as it is pervasive". Augustine of Hippo developed Paul's idea that salvation is based on faith and not "works of the law". Martin Luther's interpretation of Paul's writings heavily influenced Luther's doctrine of sola fide. The Bible does not record Paul's death.
Acts of the Apostles
Some believe that through this work, Luke intended to show the Roman Empire that the root of Christianity is within Judaism so that the Christians “may receive the same freedom to practice their faith that the Roman Empire afforded the Jews.” Those who support the view of Luke’s work as political apology generally draw evidence from the facts that Christians are found innocent of committing any political crime (Acts 25:25; 19:37; 19:40) and that Roman officials’ views towards Christians are generally positive. Also, Luke mentions a few Roman officials that believe in Jesus Christ (Acts 10:1-11:18; 13:12). The magistrates even apologize to Paul and Silas for wrongfully putting them in prison (Acts 16:38-39). By painting the Roman-Christian relations in this light, Luke hopes to persuade Rome that Christians are not enemies of the government and should not be looked upon with suspicion or even fear.
Apology on behalf of Rome addressed to the church: Whereas the claim above suggested that Luke was writing to Rome, this view proposes that Luke may be writing to the church in order to convince the saints of his own view that Rome is not a threat to the church. This claim presupposes that early Christians were suspicious of Rome or feared Roman authority as a threat to their faith. Also, supporters of this view would characterize Luke’s portrayal of the Roman Empire as positive because they believe Luke “glosses over negative aspects of the empire and presents imperial power positively.” For example, when Paul is before the council defending himself, Paul says that he is “on trial concerning the hope of the resurrection of the dead” (Acts 23:6). Some believe that this appeal “thereby shows Christian’s of Luke’s day both that their predecessors were innocent before the state and that Paul had no political quarrel with Rome” but rather with the Jews who were accusing him. Other scholars have even said that Luke wrote this apology in order to support Christians who were becoming allies with local Roman officials.
Some scholars believe that the apologetic view of Luke’s work is overemphasized and that it should not be regarded as a “major aim of the Lucan writings.” While Munck believes that purpose of Luke’s work is not that clear-cut and sympathizes with other claims, he believes that Luke’s work can function as an apology only in the sense that it “presents a defense of Christianity and Paul” and may serve to “clarify the position of Christianity within Jewry and within the Roman Empire.” Pervo disagrees that Luke’s work is an apology and even that it could possibly be addressed to Rome because he believes that “Luke and Acts speak to insiders, believers in Jesus.” Freedman believes that Luke is writing an apology but that his goal is “not to defend the Christian movement as such but to defend God’s ways in history.”
Mr. K- Yes, the conversion of the Pharasee Sal to the Apostle can be found in the Book of Acts (of the Apostles after the assention of Christ). While incarsentated, Apostle Paul wrote the Epistles that are for the born again Christian Church. Acts 22: starts his telling of his conversion, Acts 28:17- His trail. As a citizen he had the rights listed below, and if he was harmed by any of the guards, they would receive the same but times two.
Roman citizenship Rights Wikipedia, the free encyclopedia
Citizenship in ancient Rome was a privileged political and legal status afforded to freeborn individuals with respect to laws, property, and governance.
• The right to have a legal trial (to appear before a proper court and to defend oneself).
• The right to appeal from the decisions of magistrates and to appeal the lower court decisions.
• A Roman citizen could not be tortured or whipped, nor could he receive the death penalty, unless he was found guilty of treason.
• If accused of treason, a Roman citizen had the right to be tried in Rome, and even if sentenced to death, no Roman citizen could be sentenced to die on the cross.
TejonTech, you write, "...typical liberal emotional defense of a position contrary to nature..." According to theologists, that is. Scientists do not find homosexual activity to be "contrary to nature." At one time anything other than missionary position was labeled contrary to nature (even though no animal, other than humans, practice it).
gurudori, you wrote, "Not only did Apostle Paul use his Roman Citizenship to have a fair trail when the Jews wanted him excuted for converting to Christianity and blaspheme again OT..." Is this @#$% actually in the Christian Bible?
Zen...again boring...typical liberal emotional defense of a position contrary to nature...and not true.
Yeah well I think you've proven you know neither "love" nor "peace", TejonTech. What I read is the vitroil of an isolated and fearful man. It's sad really, because you drive far more people away than you'll ever attract.
What is prophesized in the Bible can't be stopped, even the New World order. Don't you think that maybe God has a backup plan for those who accepted Christ as Lord and Savior (not believing in the Pope, TT) called...... The Hope of the Return of Christ! Haven't you ever read 1 Thessalonians? It's all about how Christ returns FOR the born again believers, then Armageddon & book of Revelations happens, then Christ returns WITH the saints to reclaim earth from Satan, the god of this world, and re-establishes Eden when he got from Adam disobeying Gods commandment not to eat the fruit of knowledge. Bet you didn't know that!
Yeah, that's another one of those books in the NT most don't know of. Romans 5:9-Much more then, being now justified by his blood, we shall be saved from the wrath through him. This gives me much comfort when knowing how that state of the world is in modern times. Something to think about.
I also thought of another great example of why we need to have the separation of Church and State: Not only did Apostle Paul use his Roman Citizenship to have a fair trail when the Jews wanted him excuted for converting to Christianity and blaspheme again OT ( He was the Father to the born again Christian Church whereas Apostles Peter and James started the Catholic Church on the grounds of sticking to traditional pagen holidays- Easter is the holiday for the goddess Ester, not the Final Passover as it actually should be.)
You are going to love this TT.... Martin Luther also used his German citizenship to save his life when the Catholic Church summons him to Rome as a Jesuit priest for heresy, but he petitioned the German King for his trail to be held in a German city so he could be protected because he knew he would be assinated if he traveled to Rome. Remember him? He's the guy with the 96 thesis against the abominations within the Catholic Church? He left the Catholic Church and started the Reformation Church... got married to a former nun and lived another 30 years as the main Biblical Scholar for the King at a University in Germany.
Remember indulgences? Remember if you don't accept Jesus we will kill you period in European history? That is why the French and American constitutions added this clause in 1780s just so that any governing Church could never pull this crap again.
Remember the Inquisition? How they used church doctrine to kill thousands of pegans to take their land, indigenous people in South and North America and other believers like wicca and keltic and such? No, you seem to like to hold a rosey colored view of Catholic Church history.
CLICK HERE TO PLAY THE GAME "VOTE FOR A MORON!" If you agree with Tejon Tech last statement on "think they are voting in a new truth as if they could reverse God's creative decisions." click like, but if you do not agree with TT, click dislikes. If TT gets more dislikes than likes..... then he is a MORON! LMAO!!!
I love on this list how people clicking like and dislike think they are voting in a new truth as if they could reverse God's creative decisions.
That is what Broadbent is attempting...he makes it up to be like he would have done if he were God, even though what he would have done is simply contrary to God's obvious will and purpose.
You can't change the truth by popular vote, as Colorado is now destined to see.
This pastor is just one of the false prophets that will come in the last days. The Californication of Colorado is moving at full steam.
Jesus warns us against idolatry, fornication, and murder...seems like the secular agenda claims all three...unquestioned tolerance is idolatry, fornication is any sex outside marriage (to include all gay etc. sex and this sort of adolescent sex advocated by the morning after pill) and murder, which is what abortion is pure and simple...so Guru and Zen...the final judgment is going to be calling you to repentance and amendment of life big tie...as well as me for my sins.
Secularism isn't new, TT, it was how our country was originally founded with Seperation of Church and State, so don't try to re-write history. It has only been since the 1980's when the evangical churches started a movement to insert Christian morality into our governmental laws. So why can't each and every person govern themselves instead of having to follow your brand of religion? Just because we don't want it in our governing laws doesn't mean we don't practice morality and personal spirituality in our homes.
From Wikepedia: Seperation of Church and State: Thomas Jefferson:
In English, the exact term is an offshoot of the phrase, "wall of separation between church and state", as written in Thomas Jefferson's letter to the Danbury Baptist Association in 1802. In that letter, referencing the First Amendment to the United States Constitution, Jefferson writes: "Believing with you that religion is a matter which lies solely between Man & his God, that he owes account to none other for his faith or his worship, that the legitimate powers of government reach actions only, & not opinions, I contemplate with sovereign reverence that act of the whole American people which declared that their legislature should 'make no law respecting an establishment of religion, or prohibiting the free exercise thereof,' thus building a wall of separation between Church and State." Jefferson reflected his frequent speaking theme that the government is not to interfere with religion.
The Bill of Rights was one of the earliest examples in the world of complete religious freedom (adopted in 1791, only preceded by the Declaration of the Rights of Man and of the Citizen in 1789) but it was interpreted as establishing a separation of Church and State only after the letter of Jefferson (see section United States for more details). At the time of the passage of the Bill of Rights, many states acted in ways that would now be held unconstitutional, some of them with official state churches. All of the early official state churches were disestablished by 1833.
Milligan's primary goal is to advance the new world order in her own image without a God to interfere with her reign of political correct totalitarianism...it is to turn Colo Spgs upside down, and that sort of radical transformation will not bring peace and stability, but strive and division.
Zen...Denver Seminary? That explains why you are an advocate for the new secularism and not the Christianity of the Apostles. Your education is faulty and doesn't serve you well.
The religion of Jesus is one where God's love directs and rules our hearts toward peace now and eternity ultimately.
Your religion of permissiveness and self affirmation is a direct path to pain now and dysfunction in the future...not something a loving God would wish for his children.
God, as scripture says, has a special place for wolves in sheep's clothing like you.
If "Milligan is a far left whack job" then how far off the right edge of the map are you? Geez TT .. some days you make Pinochet look like a centrist.
Another 14 jobs and more young people gone. Good job blue hairs. As for Pico, he's a egotistical hack. I used to debate that guy on the Gazette, and he wouldn't know good science from a pile of sh*t. Like most of the council, he's a slave to ideology and blind to on the ground reality.
TejonTech, speaking as one with a degree in Religious Studies, who studied theology and ministry at Denver Seminary, and has worked in Protestant and Catholic church and para-church organizations, I can confidently and authoritatively say that you my friend are no Christ follower. You're a Pharisee. And a milk fed one at that. It's time to take back the church from people like you ... people who have overseen the largest single decline in US church attendance in history. If Jesus were to return today, I have zero doubt you'd be first to pick up a hammer and nail. You genuinely have no idea what you do. And for that, I just feel sorry for you. Grow up milk fed ... before it's too late. Good luck with all that self-righteous rage.
TejonTech it is truly sad to see a person so tied up in knots as you.
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what is Roller chains
Roller chain is a steel linked chain that utilizes roller bushings at each connecting link. The bushings aid the chain in riding smoothly around a sprocket and give the chain long life as well as strength. Roller chain is commonly found on bicycles and farming machinery and is also a primary component in automobile transmissions and transfer cases. Some high-performance types of roller chain use small rubber O-rings at each end of the bushings to aid in the retention of oil, which helps keep the chain in peak condition.
There are many types of roller chain, each intended for a specific purpose. In the U.S., roller chain is sized by the American National Standards Institute or ANSI with the most common sizes being 40, 50 and 60. The size of the chain is reflective of the pitch of the chain in eighths of an inch (0.3175 centimeters), this is denoted by the first digit, and the final digit noting the strength of the chain. While 0 represents standard chain and 1 represents lightweight chain, 5 is used to show bushed chain with no rollers. This means that a standard bicycle chain with a half-inch (1.27 centimeters) pitch would be a size 40 chain.
The typical roller chain is comprised of links that are fused together by pins. The pins are driven through the ends of each link and held in place by friction. Each chain is connected at the ends to form a complete circle or chain loop by a master link. The master link is a link of chain that uses a clip to hold the sides in place rather than being a friction fit. Roller chain can be shortened by removing links with a chain breaking tool and lengthened by adding whole or a half links.
Lubrication and proper tension is critical to assure long life for any roller chain. A chain should never be run tight. There should always be a slight amount of slack in a properly adjusted chain. The school of thought is approximately 2 percent to 4 percent of the distance between the centers of the sprockets. Clean, light-weight oil should be used to keep the chain properly lubricated.
The various uses for roller chain include not only bicycles, but conveyors, automobile timing chains and chain saws. By attaching tiny cutting teeth to a chain, a chain saw is able to cut its way through a tree in a rapid manner. In another application, small lengths of chain are attached to a handle, allowing plumbers to grip and twist pipe sections.
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Definitions for wageweɪdʒ
Random House Webster's College Dictionary
wageweɪdʒ(n.; v.)waged, wag•ing.
(n.)Often, wages. money that is paid or received for work or services.
Ref: Compare living wage , minimum wage. 1
wages, recompense or return:
The wages of sin is death.
Obs. a pledge or security.
(v.t.)to carry on (a battle, argument, etc.):
to wage war.
Obs. to stake or wager. to pledge.
(v.i.)Obs. to contend; struggle.
Origin of wage:
1275–1325; ME: pledge, security < AF; OF guagegage1< VL *wadium < Gmc (see wed )
wage, pay, earnings, remuneration, salary(verb)
something that remunerates
"wages were paid by check"; "he wasted his pay on drink"; "they saved a quarter of all their earnings"
carry on (wars, battles, or campaigns)
"Napoleon and Hitler waged war against all of Europe"
An amount of money paid to a worker for a specified quantity of work, usually expressed on an hourly basis.
To wager, bet.
To employ for wages; to hire.
To conduct or carry out (a war or other contest).
to wage war
Origin: from wage, a northern variant of gauge, gage, from *waddi, wadja (cognate with wedd), from wadjō, from wadh-. Akin to veþja "to pledge", wadi. More at wed.
to pledge; to hazard on the event of a contest; to stake; to bet, to lay; to wager; as, to wage a dollar
to expose one's self to, as a risk; to incur, as a danger; to venture; to hazard
to engage in, as a contest, as if by previous gage or pledge; to carry on, as a war
to adventure, or lay out, for hire or reward; to hire out
to put upon wages; to hire; to employ; to pay wages to
to give security for the performance of
to bind one's self; to engage
that which is staked or ventured; that for which one incurs risk or danger; prize; gage
that for which one labors; meed; reward; stipulated payment for service performed; hire; pay; compensation; -- at present generally used in the plural. See Wages
Translations for wage
Kernerman English Multilingual Dictionary
(alsoˈwages noun plural) a regular, usually weekly rather than monthly, payment for the work that one does
He spends all his wages on books; What is his weekly wage?
- salárioPortuguese (BR)
- der LohnGerman
- μισθός, (οικονομικές) απολαβέςGreek
- salario, sueldoSpanish
- mjesečna plaćaCroatian
- laun, kaupIcelandic
- 임금, 급료, 삯Korean
- darba algaLatvian
- gaji, upahMalay
- lønn, gasjeNorwegian
- lön, avlöningSwedish
- ค่าจ้าง; ค่าแรงThai
- 報酬，薪資Chinese (Trad.)
- заробітна платаUkrainian
- lương tuầnVietnamese
- 工资，报酬Chinese (Simp.)
Get even more translations for wage »
| 3.135191 |
Harris, Paul L.
Trusting What You're Told
How Children Learn from Others
Aims and Scope
If children were little scientists who learn best through firsthand observations and mini-experiments, as conventional wisdom holds, how would a child discover that the earth is round—never mind conceive of heaven as a place someone might go after death? Overturning both cognitive and commonplace theories about how children learn, Trusting What You’re Told begins by reminding us of a basic truth: Most of what we know we learned from others.
Children recognize early on that other people are an excellent source of information. And so they ask questions. But youngsters are also remarkably discriminating as they weigh the responses they elicit. And how much they trust what they are told has a lot to do with their assessment of its source. Trusting What You’re Told opens a window into the moral reasoning of elementary school vegetarians, the preschooler’s ability to distinguish historical narrative from fiction, and the six-year-old’s nuanced stance toward magic: skeptical, while still open to miracles. Paul Harris shares striking cross-cultural findings, too, such as that children in religious communities in rural Central America resemble Bostonian children in being more confident about the existence of germs and oxygen than they are about souls and God.
We are biologically designed to learn from one another, Harris demonstrates, and this greediness for explanation marks a key difference between human beings and our primate cousins. Even Kanzi, a genius among bonobos, never uses his keyboard to ask for information: he only asks for treats.
- 272 pages
- 3 halftones, 3 line illustrations, 19 graphs
- HARVARD UNIVERSITY PRESS
| 3.588708 |
Early in his career, James McNeill Whistler submitted Symphony
in White, No.1:The White Girl to two esteemed
annual European exhibitions—the Royal Academy in London, England,
and the Paris Salon in France. The painting was rejected at both.
It was shown in a less notable exhibition in 1863 and received tentative
reviews. While the painting’s white tones and the lily held
by the woman imply purity, her morning dress and disheveled hair
suggest impropriety. This ambiguity baffled the European critics
and public: “Folk nudged each other and went almost into hysterics;
there was always a grinning group in front of [The
White Girl].”—Emile Zola, novelist, 1886;
“It is one of the most incomplete paintings we have ever met
with. A woman, in a quaint morning dress of white, with her hair
about her shoulders, stands alone, in the background of nothing
in particular.”—F.G. Stevens, critic, June, 1862.
Critics tried to create a story behind the painting’s subject,
interpretations. They called the model a “sleepwalker,"
"a newly deflowered bride," and an "apparition.”
Whistler left no clues as to how the painting should be read. He
said, “My painting simply represents a girl dressed in white
standing in front of a white curtain.” The real “story”
was Whistler’s manifestation of art for art’s sake—his
focus on color, line and composition—not the subject matter
of the painting.
When the painting was shown in the United States 10 years later,
the public generally reacted differently. The model was described
as “attractive and even fascinating” with a “singular
and an indescribable face, full of the strangest and subtlest expression.”
American artists soon imitated the work, creating their own paintings
in the manner of Whistler’s White Girl.
| 3.035661 |
THE FRAGILE FAUNA OF ILLINOIS CAVES
by Steven J. Taylor and Donald W. Webb
Illinois has several hundred caves, many of them in nearly pristine condition.
This unique and fragile environment is home to a diverse array of creatures,
including organisms that are completely limited to the cave environment,
species that may be found in similar habitats above ground, and the many
animals that accidentally wander, fall, or are washed into caves. Many
cave animals are highly adapted for the unique and harsh living conditions
they encounter underground.
caves can be found in four distinct karst regions: in the Mississippian
limestone of the Shawnee Hills, in the Salem Plateau and in the Lincoln
Hills, and in the Ordovician limestone of the Driftless Area. These caves
have been forming though the interaction of geology vegetation, and rainfall
for the past 300 million years. Shallow seas covered much of Illinois
during the Mississippian Period. When the seas receded, forests grew over
the exposed sedimentary rocks; and rainwater-which had become slightly
acidic through interaction with carbon dioxide from both the atmosphere
and the bacterial breakdown of organic material-then seeped into cracks
and bedding planes. As the limestone dissolved, conduits formed. These
conduits eventually developed the geologic features characteristic of
karst terrain-caves, sinking streams, springs, and sinkholes.
INTO THE TWILIGHT ZONE
Caves can be divided into three ecological zones. The entrance zone is
similar in light, temperature, and relative humidity to the surrounding
surface habitat, and the creatures that live there resemble the animals
that live in the moist shaded areas near the cave. Hear we find the eastern
phoebe (Sayornis phoebe), a small gray bird whose nest is constructed
on bare bedrock walls out of mosses and other debris. In the leaf litter,
we find many animals of the forest floor: redbacked salamanders, harvestmen
(or daddy-longlegs), snails, earthworms, millipedes, centipedes, beetles,
ants, and springtails. Cave entrances are often funnel shaped or have
sheer vertical walls, and organisms and organic debris tend to concentrate
at the bottom. The entrance zone also provides a highly protected environment
for overwintering organisms.
Deeper inside the cave, in the twilight zone, there is much less light,
and photosynthesizing plants are no longer able to grow. The temperature
and relative humidity fluctuate here, but the environment is usually damp
and cool. Many animals from the entrance zone wander into the twilight
zone, but most of these creatures must eventually return to the land above.
Several species of cave crickets are common in this part of the cave,
sometimes appearing in large numbers on walls or ceilings.
In larger caves, there is a dark zone characterized by constant temperature
(about 54-58*F in Illinois) and the absence of light. Here, the relative
humidity approaches the saturation point. Many animals in the dark zone
are capable of completing their entire life cycles without leaving the
cave although food is scarce in the absence of photosynthesis. In this
zone, there are fewer species of organisms. Creatures who live here eat
primarily organic debris-wood, leaves, and accidental animals. Dark-zone
dwellers get some of their nutrients from the feces of bats and cave crickets,
animals that leave the cave at night to feed on the surface. Raccoons,
common cave explorers in Illinois, also leave their waste behind. A wide
array of bacteria and fungi feast upon these nutrient-rich items. Other
animals then feed upon the fungi and bacteria. Springtails, minute insects
typically overlooked by the casual observes, are important fungus feeders,
and a variety of beetles, flies, and millipedes get their nourishment
this way as well. These organisms may then become the prey of cave-inhabiting
spiders, harvestmen, predacious fly larvae known as webworms, and an occasional
cave salamander. In the winter, pickerel frogs, mosquitoes, and some moths
move into cave to wait for warmer weather.
ADAPTING AND SURVIVING
Common Cave inhabitants
include (left to right) the moth, Scoliopteryz libatrix,
which does not have a comon name; the cave salamander (Eurycea
lucifuga); and the monorail worm (Macrocera nonilis).
Animals that live in caves vary greatly in their degree of adaptation
to the cave environment. Accidental animals live there only temporarily;
they will either leave or die. Animals that frequent cave but must return
to the surface at some point in there life cycles are know as trogloxenes.
Bats and cave crickets are two examples. Troglophiles are animals that
can complete their entire life cycles within a cave, but they may also
be found in cool, moist habitats outside of caves. Tow troglophilic vertebrates
found in or near Illinois caves are the cave salamander (Eurycea lucifuga)
and the spring cavefish (Forbesicthys agassizi).
Diane Tecic, district
heritage biologist for the Illinois Department of Natural Resources,
looks for cave-adapted organisms in organic debris with Illinois
caver Tim Sickbert.
Most cave animals are trogloxenes and troglophiles; only 20 to 30% of
the animals in North American caves are troglobites. Troglobites are animals
that live exclusively in caves; they are especially interesting because
of their unique morphological, physiological, behavioral, and life-history
adaptations. Many troglobites, for example, lack body pigment. Because
they live where there is no light, there is no evolutionary advantage
for them in maintaining the colors that might be characteristic of their
relatives and ancestors that live above ground. In cave-adapted species,
the evolutionary pressure to maintain functional eyes is also greatly
reduced, and these species have been under strong selective pressure to
evolve other means of sensing their surroundings. Their legs and antennae
usually have more sensory nerve endings than related above-ground species.
These appendages serve important tactile functions and are often greatly
elongated in cave-dwelling creatures.
Adaptations that allow species to exist in an environment with very low
nutrient input are not as obvious. Many cave-adapted species produce fewer
offspring than their surface-inhabiting relatives, but individual eggs
may contain more nutrients. In some species, timing of reproduction may
be synchronized with spring flooding and its new supply of nutrients.
Other species, lacking the above-ground seasonal cues of temperature and
photoperiod, may reproduce year-round. Cave adaptations may include a
reduced metabolic rate, allowing animals to live on limited food resources
for long periods of time. Illinois has many troglobitic invertebrates
but no troglobitic vertebrates.
As cave-adapted species become specialized, they also tend to become
geographically isolated. The geological and hydrological history of some
areas may divide species into isolated populations, and these populations,
over time, may evolve into distinct species. During glacial periods, caves,
as serve as refugia for some aquatic, soil-, and litter-inhabiting animals.
These species may become "stranded" in caves when glaciers retreat
surface conditions are not suitable for recolonization.
VULNERABITLIY OF CAVE ENVIRONMENTS
Human disturbance affects cave ecosystems just as it affects other ecosystems.
As a result of changes we make on the surface, we unknowingly alter cave
environments, destroying unique and valuable organisms before we even
know of their existence. The public knows very little about caves and
the organisms that inhabit them. Small wonder then that the importance
of protecting groundwater, caves, and cave life is not fully appreciated.
It is not uncommon to find sinkholes filled with trash, serving as natural
garbage cans for rural waste disposal. Visitors sometimes permanently
damage caves with graffiti, break stalactites and stalagmites, and carelessly
The very adaptations that allow troglobites to survive in the harsh cave
environment make these animals more vulnerable to changes made by humans.
The reduced metabolic rates that allow these animals to survive in a nutrient-poor
environment also make them less competitive when organic enrichment is
introduced in the form of fertilizers, livestock and agricultural waste,
and human sewage. In Illinois, this effect is commonly seen in stream-inhibiting
amphipods (small shrimplike animals) and isopods (small crustaceans related
to terrestrial pillbugs or sowbugs). These groups contain troglobites
that are highly adapted to cave environments; they also contain more opportunistic
troglophilic species, which have a competitive advantage in the presence
of high levels or organic waste.
Amphipods and isopods feed on small particles of organic debris and on
decomposers such as bacteria and fungi. Because they ingest large quantities
of this material, they are exposed to contamination from a variety of
pollutants. In Illinois, samples of these animals collected in 1992 were
found to contain dieldrin and breakdown products of DDT. They were also
found to contain moderate levels of mercury, although mercury was not
detected in any water samples from the same sites.
Sedimentation also threatens aquatic species. Topsoil run-off from rural
development and agricultural fields enters caves readily when vegetative
buffers around sinkholes are too small or nonexistent. This sediment fills
the spaces in gravel streambeds, eliminating the microhabitats that allow
many cavedwelling species to exist. As a result, cave streams with high
sediment loads ten to contain few species.
Sometimes, humans can't easily see the value of these subterranean systems,
especially when their own interests conflict with the health of cave communities.
Such a conflict is occurring now in our most biologically and hydrologically
significant karst area, the Salem Plateau of Monroe and St. Clair counties.
As part of the greater St. Louis metropolitan area, the Salem Plateau
is experiencing rapid population growth. Scientists can estimate the level
and types of threats that this growth brings to the biological integrity
of the region, but it's much more difficult to develop protected areas,
educational programs, and new regulatory mechanisms within the existing
political, social, and geographic framework. Illinois caves are a high
priority for conservation because cave organisms face serious threats
from agriculture and increasing urbanization. Also, the unique and fragile
cave and environment provides a home for organisms found nowhere else
in the world.
It is not usually possible to include the entire drainage basin of significant
caves within nature preserves or other conservation easements. To manage
a cave effectively, scientists must understand the hydrology of a cave's
subterranean conduits. This knowledge is gained by doing extensive dye
tracing studies and cave mapping. Both of these activities are time- and
labor-intensive. Already, the drainage basins of some of our largest cave
systems are being compromised by agriculture and rural housing projects.
Educating the public-particularly politicians, farmers, and children-about
land use and the impact of human activities is key to the long-term health
of cave communities. We must also enact appropriate regulations for rural
residential development-especially wastewater treatment-and for agricultural
activities in a karst landscape.
For more information on cave conservation and management, contact the
National Speleological Society, 2813 Cave Avenue, Huntsville, AL 35810-4431,
or Steven Taylor or Donald Webb at the Center for Biology, Illinois Natural
History Survey, 607 East Peabody Drive, Champaign, IL 61820.
Steven J. Taylor is an aquatic entomologist in the
Center for Biodiversity at the Illinois Natural History Survey in Champaign.
Donald W. Webb is an insect systematist, also at the Center for Biodiversity.
A GOOD NEIGHBOR POLICY
In a few caves in Monroe and St. Clair counties, you can find a
small shrimplike creature that exists nowhere else in the world.
The Illinois cave amphipod has made our corner of the world its
home, but it may not be here long unless humans take steps to protect
its environment. This unassuming cave creature has been proposed
for listing as a federally endangered species.
Cave amphipods inhabit the bottoms of pools and riffles in large
cave streams, where they creep among cobbles and under stones, feeding
on decaying leaf litter and organic debris. Food is scarce in this
environment, and the amphipods have developed chemosensory structures
that detect the odor of food sources, such as dead or injured animals.
Injured or dying amphipods are vulnerable to such predators as
flatworms, cave salamanders, and even other amphipods. But
the greatest threat these vulnerable creatures face is the
deterioration of the environment. The Illinois cave amphipod
lives near the greater St. Louis metropolitan area, a region
that has been experiencing dramatic population growth for
the past 10 years. Continued urbanization without appropriate
sewage treatment and disposal is especially threatening to
the amphipods existence. Other serious threats are siltation
and the presence of agricultural chemicals in subterranean
Fortunately for the amphipod, the quality of life for people on
the land above depends on water quality in streams below. Because
agricultural chemicals and bacteria associated with sewage have
been found in well water, springs, and cave streams in this area,
a concerted effort is being made to improve the water quality in
this karst region. Efforts to provide communities with safe drinking
water could also provide a healthy cave environment and help ensure
the further existence of our underground neighbor, the Illinois
| 3.772562 |
|Uploaded:||January 6, 2013|
|Updated:||January 7, 2013|
This tutorial is aimed to teach how to draw an accurate dromaeosaur, the family of theropods often called raptors, using a Velociraptor as example. The tut is divided in two parts. The first part is a basic explanation of what is and what is not a dromaeosaur: the difference between the movies/pop culture blood thirsty beasts, and the real animal (or at least an aproximation). The second part is a step-by-step to draw your own Velociraptor in a dynamic pose. Again, I simplified enough so everyone can do it easily, omiting certain details that you only can achieve by study and understanding the anatomy of the animal. Ask me if you have any doubt. Hope you like it!!
| 3.196799 |
Eight new grants administered by NIDA aim to channel students' natural fascination with their behavior and their brains into appreciation and enthusiasm for neuroscience. Grantees are developing K-12 education programs that will engage young people in learning about the brain, inspire some to pursue careers in biomedical science, and increase teacher knowledge of neuroscience. The 5-year grants are funded by the NIH Blueprint for Neuroscience Research Science Education, a cooperative effort among the 16 NIH Institutes, Centers, and Offices that support neuroscience research and the Science Education Partnership Award Program of the Division of Program Coordination, Planning, and Strategic Initiatives, Office of the Director, National Institutes of Health.
Dr. Susanna Cunningham of the University of Washington, Seattle, will develop two programs in the neuroscience of learning and cognition for middle school science teachers, students, parents, and community groups. Teachers will have the opportunity to increase their knowledge by participating in a Summer Institute and online Professional Learning Community. An online project for students will be designed to broaden their knowledge of the brain and learning processes, scientific research processes, and neuroscience careers.
Dr. Eric Chudler heads a University of Washington project that will teach middle school students how chemicals in plants and herbs influence health and behavior. A supplementary educational resource kit will supply teachers with inquiry-based, hands-on science activities. Students may attend a summer camp to learn more about neuroscience, mental health, neurological fitness, and careers in the biomedical sciences.
Dr. Michael Kavanaugh of the University of Montana, Missoula, will collaborate with the Exploratorium in San Francisco to create the Brainzone, a neuroscience learning center. Designed for K-12 students and adults, the Brainzone will feature four exhibits, a computer learning laboratory to teach neuroscience lessons, and a working laboratory with research-grade electroencephalogram (EEG) instrumentation and materials for the study of fruit fly neurobiology. The Brainzone will open in a high-profile retail mall that tallies 7 million annual visits and will also travel to isolated, underserved, rural, and tribal schools throughout the state.
Dr. Dina Markowitz of the University of Rochester in New York will develop, field test, disseminate, and evaluate hands-on activities that focus on key concepts of neuroscience for high school biology students. The activities, designed so that teachers can easily integrate them into existing curricula, will also educate students about the ways in which neuroscience research directly applies to their lives as well as about careers that require neuroscience knowledge. This project will also recruit, train, and support a network of teacher-presenters who will lead professional development workshops for their peers throughout New York and the United States.
Dr. Leslie Miller of William Marsh Rice University in Houston will develop a game-based Web site to help high school students understand the role of clinical trials in the research process. Players will assume various professional roles in clinical trial simulations, learning about scientific discovery and the testing and adoption of new treatments based on neuroscience research.
Dr. Nancy Moreno of Baylor College of Medicine in Houston leads a group that will develop, evaluate, and disseminate an inquiry-based science and health curriculum to enhance students' neuroscience knowledge and understanding in grades K-5. Teachers will be able to implement the curriculum, which will include elements of reading and language arts, in school or informal learning settings. Major educational Web sites—including BioEd Online (www.bioedonline.org) and K8 Science (www.k8science.org—will offer the curriculum, student activities and materials, and resources for teachers.
Dr. Steven Snyder of the Franklin Institute in Philadelphia will collaborate with the University of Pennsylvania to engage K-12 students and teachers in learning about the importance of neuroscience in their world through the development of programs at the Institute, a high school course, and a digital toolkit of educational materials for K-12. The programs will help students understand how the brain interacts with the rest of the body to shape responses to the environment. The activities will emphasize personal aspects of health and behavior.
Dr. Louisa Stark of the University of Utah in Salt Lake City will develop inquiry-based, multimedia educational applications for touch-interface devices to teach students the neurophysiology of the five senses. The applications will demonstrate how research can lead to improved treatments for sensory impairments. Local, state, regional, and national workshops will prepare middle school and high school teachers to use the applications, which will be disseminated without charge via the Internet.
| 3.140824 |
There are many types of biomass—organic matter such as plants,
residue from agriculture and forestry, and the organic component of
municipal and industrial wastes—that can now be used to produce fuels,
chemicals, and power. Wood has been used to provide heat for thousands of
years. This flexibility has resulted in increased use of biomass
technologies. According to the Energy Information Administration, 53% of
all renewable energy consumed in the United States was biomass-based in
Biomass technologies break down organic matter to release stored energy
from the sun.
Biofuels are liquid or gaseous fuels produced from biomass. Most biofuels
are used for transportation, but some are used as fuels to produce
electricity. The expanded use of biofuels offers an array of benefits for
our energy security, economic growth, and environment.
Current biofuels research focuses on new forms of biofuels such as
ethanol and biodiesel, and on biofuels conversion processes.
Ethanol—an alcohol—is made primarily from the starch in corn grain. It
is most commonly used as an additive to petroleum-based fuels to reduce
toxic air emissions and increase octane. Today, roughly half of the
gasoline sold in the United States includes 5%-10% ethanol.
Biodiesel use is relatively small, but its benefits to air quality are
Biodiesel is produced through a process that combines
organically-derived oils with alcohol (ethanol or methanol) in the
presence of a catalyst to form ethyl or methyl ester. The biomass-derived
ethyl or methyl esters can be blended with conventional diesel fuel or
used as a neat fuel (100% biodiesel).
Biomass resources include any plant-derived organic matter that is
available on a renewable basis. These materials are commonly referred to
Biomass feedstocks include dedicated energy crops, agricultural crops,
forestry residues, aquatic crops, biomass processing residues, municipal
waste, and animal waste.
Dedicated energy crops
Herbaceous energy crops are perennials that are harvested annually after
taking 2 to 3 years to reach full productivity. These include such grasses
as switchgrass, miscanthus (also known as elephant grass or e-grass),
bamboo, sweet sorghum, tall fescue, kochia, wheatgrass, and others.
Short-rotation woody crops are fast-growing hardwood trees that are
harvested within 5 to 8 years of planting. These include hybrid poplar,
hybrid willow, silver maple, eastern cottonwood, green ash, black walnut,
sweetgum, and sycamore.
Agricultural crops include currently available commodity products such as
cornstarch and corn oil, soybean oil and meal, wheat starch, and vegetable
oils. They generally yield sugars, oils, and extractives, although they
can also be used to produce plastics as well as other chemicals and
Agriculture Crop Residues
Agriculture crop residues include biomass materials, primarily stalks and
leaves, that are not harvested or removed from fields in commercial use.
Examples include corn stover (stalks, leaves, husks, and cobs), wheat
straw, and rice straw. With approximately 80 million acres of corn planted
annually, corn stover is expected to become a major feedstock for biopower
Forestry residues include biomass not harvested or removed from logging
sites in commercial hardwood and softwood stands as well as material
resulting from forest management operations such as pre-commercial
thinning and removal of dead and dying trees.
There are a variety of aquatic biomass resources, such as algae, giant
kelp, other seaweed, and marine microflora.
Biomass Processing Residues
Biomass processing yields byproducts and waste streams that are
collectively called residues and have significant energy potential.
Residues are simple to use because they have already been collected. For
example, the processing of wood for products or pulp produces unused
sawdust, bark, branches, and leaves/needles.
Residential, commercial, and institutional post-consumer waste contains a
significant proportion of plant-derived organic material that constitute a
renewable energy resource. Waste paper, cardboard, wood waste, and yard
waste are examples of biomass resources in municipal waste.
Farms and animal-processing operations create animal wastes that
constitute a complex source of organic materials with environmental
consequences. These wastes can be used to make many products, including
Some biomass feedstocks, such as municipal waste, are found throughout
the United States. Others, such as energy crops, are concentrated in the
eastern half of the country. As technologies develop to more efficiently
process complex feedstocks, the biomass resource base will expand.
Collecting Gas from Landfills
Landfills can be a source of energy. Organic waste produces a gas called
methane as it decomposes, or rots.
Methane is the same
energy-rich gas that is in natural gas, the fuel sold by natural gas
utility companies. It is colorless and odorless. Natural gas utilities add
an odorant (bad smell) so people can detect seeping gas, but it can be
dangerous to people or the environment. New rules require landfills to
collect methane gas as a pollution and safety measure.
compiled from The British Antarctic Study, NASA, Environment Canada,
UNEP, EPA and other sources as stated and credited Researched by Charles
Welch-Updated daily This Website is a project of the The Ozone Hole Inc.
a 501(c)(3) Nonprofit Organization http://www.theozonehole.com
| 3.811603 |
In the September issue of ELECTRICAL CONTRACTOR, there was an Industry Watch story titled “Efficiency from the Wall to the PC,” about an organization that is campaigning for more efficient power “cords.” There was a reference to a quote indicating only 50 percent of the power that leaves the outlet reaches the PC because energy “leaks” out of inefficient power cords. However, a typical PC line cord has 0.3 ohms of resistance. If the computer consumes 720W, that is 6A on 120V circuit. The power loss in the cord is 6A^2*0.3 ohm = 7.8W. Relative to the computer itself, that is approximately a 1 percent loss of power delivered from the outlet, a 99 percent efficiency rating.
A few readers wrote to us about the inaccurate terminology. It should have read power “supplies,” and, of course, energy does not literally “leak” out of the power cord. It is lost within the inefficient components, such as the computer’s power supply.
As with most power quality issues, Ohm’s and Kirchoff’s Laws still apply here. These rules are how we calculate the voltage and current through an electrical distribution system or an electronic circuit. Next, we need another similar equation, where power = voltage × current (though not necessarily a simple math multiplication in most cases with today’s systems). Finally, the formula for efficiency is useful power output divided by the total electrical power consumed.
In electrical engineering terms used by the utility companies, this definition equates to the parameter called “power factor” (PF). Many people today use the term “true power factor,” which is the watts (W) divided by the volt-amperes (VA). This agrees with the definition above. The W is the power used by the load. It is divided by the VA, which is the power delivered by the utility company, to obtain the PF.
Of course, having a term called “true power factor” implies there is another term called “false power factor,” which isn’t correct; the opposite term is “displacement power factor” (DPF), which is the cosine of the angle between the voltage and current. In the old days prior to harmonic distorted and unbalanced systems, PF and DPF would be equal—but not anymore. However, that is a discussion for another day.
The Web site from which the misworded quotes originated explains the inefficiency of the individual voltage regulators on other boards within the computer, as well as the load of the heating, ventilating and air conditioning (HVAC) systems to remove the heat from the building, and so on, further reducing the efficiency. Since most HVACs today use adjustable speed drives to be more efficient, the efficiency of the heat removal depends on the load that is directly impacted by the ambient temperature and emitted temperature from the loads, among other factors.
The article on the Web site references an Electric Power Research Institute study on the efficiency of power supplies themselves. Efficiency of just a computer’s power supply depends on a number of factors, including the percentage of full-rated power that is being drawn from power supply, operating temperature, input AC voltage level and so on. What this graph doesn’t tell is, at lower loading, the current harmonic distortion goes up. So the real efficiency would have to account for the increased losses in the power transformers due to harmonic currents. Of course, the lower load means less power itself is being consumed, hence less carbon, energy and, therefore, money.
You can see that determining the true efficiency of a computer needs accounting for many variables that can make the answer vary quite significantly. So, I advise anyone to take any claims of money savings through efficiency with a grain of salt. What I really think is important is not the efficiency, but the effectiveness of the power supplied. Efficiency should not be confused with effectiveness: A system that wastes most of its input power but produces exactly what it is meant to is effective but not efficient. The term efficiency only makes sense in reference to the desired effect.
Examples include the incandescent light bulb—2 percent efficiency at emitting light; electronic amplifier—50 percent efficiency to speakers; and electric kettle—90 percent efficiency in boiling water. In a computer, the efficiency is significantly affected by the microprocessor. This has been brought to the forefront with AMD’s introduction of its newly minted quad-core processor, which is code-named Barcelona. According to InfoWorld, “the chip delivers more than twice the combined integer and floating-point performance of its two-core predecessor at the same thermal envelope … . That, to me, is a textbook example of a green technological advancement. It means AMD has minted a processor with significantly higher performance per watt than its predecessor, a metric that’s becoming increasingly important to datacenter operators.”
So to readers who spotted the miswording that, if true, would have resulted in changing the laws of physics with regards to power cords efficiency, thank you for helping to get this corrected. And to those concerned about efficiency, perhaps we should broaden the scope to encompass the complete picture of effectiveness—what power the electric utility must supply to perform the work the consumer requires, whether a computer or an entire facility. EC
BINGHAM, a contributing editor for power quality, can be reached at 732.287.3680.
| 3.395198 |
AS the electoral turmoil faded into the background, Ukraine marked two important anniversaries last week. The first was eight years since the Orange Revolution of 2004. The second was eight decades since the Holodomor.
Holodomor literally means death by hunger. In 1932 and 1933, a vast famine in Soviet Ukraine killed three to seven million people, according to estimates. While people starved, the grain was shut away in barns for export. Many historians agree that the famine was man-made; some say it was genocide.
Yet the Holodomor is not widely known about outside Ukraine. In the 1930s, it was hushed up by many western correspondents in return for access to the Kremlin. Among them was Walter Duranty of the New York Times, who received the Pulitzer Prize for his reporting from the USSR. (There have been calls to revoke his Pulitzer posthumously, so far unsuccessful). One of the exceptions was Welsh journalist Gareth Jones whose reporting of the Ukrainian famine had him banned from the USSR. He was later killed in mysterious circumstances at the age of only 29. Meanwhile, the cover-up has left “profound consequences for Ukraine, which remains poorly understood in the West,” says Rory Finnin, a lecturer in Ukrainian Studies at Cambridge University, where Mr Jones had been a student.
Viktor Yushchenko, the former president of Ukraine, did a lot to raise awareness about the Holodomor. Kyiv now houses a stirring candle-shaped memorial and Holodomor museum. But the leader of the 2004 Orange Revolution has fallen from grace. In the October elections, Mr Yushchenko’s party, Our Ukraine, got just 1% of the vote, losing all its 72 seats in parliament. On the anniversary of the Orange Revolution last week only a small crowd gathered on the legendary Independence Square. Someone had brought along a portrait of Yulia Tymoshenko, the heroine of the Orange Revolution who remains behind bars. Another woman held a single orange.
The tragedy of 1932-1933 has become politicised. In his view of the Holodomor, the current president, Viktor Yanukovych, has differed from his predecessor. For the third year now, the commemorations took place without state support.
Even so, on November 23rd events went ahead in cities across Ukraine. People could taste the dishes made out of tree bark that were eaten during the famine. Other symbolic actions evoked the “uncelebrated weddings”, the “unrealised talents” and the “meetings that never took place”. This year, the focus was on those who saved others from starvation. Before dusk 2,000 people gathered under the Holodomor memorial in Kyiv, decorated with loaves of bread, bunches of wheat and a sea of candles. At 4pm, there was a moment of silence and people across Ukraine lit candles in their windows.
Octogenarian Kateryna, who grew up in the countryside before moving to Kyiv in the 1940s, was sitting beside a candle burning in her kitchen. She heaps sugar into her china teacup. “Three spoonfuls!”, she says. “In Ukraine we remember the hunger. Perhaps that is why we are fond of sugar”.
| 3.035 |
In this lecture you will learn how to undertake Solving Quadratic Systems. First you will start with Linear Quadratic Systems as well as their Solutions, before you move into Quadratic Quadratic Systems and their Solutions. Lastly, you will learn how to solve Systems of Quadratic Inequalities.
linear-quadratic system, use substitution to solve.
quadratic-quadratic system, use elimination to solve.
inequalities, remember the conventions about graphing boundaries
using either solid or dotted lines.
If possible, check
your solutions to systems of equations by graphing.
Solving Quadratic Systems
Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.
| 4.057169 |
Located in downtown San Salvador, this architectural marvel from the nineteenth century has witnessed some of the most important events in the political history of El Salvador.
The first national palace was built from 1866 to 1870 but a fire wiped-out the structures on December 1889; years later the government of Pedro José Escalón (1903) conducted a public contest for the design and construction of the new palace. The winner of the contest was José Emilio Alcaine, engineer and master builder Pascasio González Erazo.
Considered the first building of the Republic, it was also called “The Coffee Palace “, because a legislative decree taxed coffee exports to pay for the construction. 1 Columbus per 1 Quintal (100 kilograms) was charged, in total 50 thousand Colones were collected.
The main portal is composed of six towering columns that are accompanied by the statues of Christopher Columbus and Queen Isabel the Catholic, donated by King Alfonso XIII in 1924.
The Palace has an eclectic style, with Ionic, Corinthian and Roman columns and elements.
This beautiful building retains most of its original materials like glassware from Belgium, marble from Italy and wood from El Salvador. Over the years this building was abandoned, but in 1980 it was declared a National Monument, which prompted restoration work to rescue this historic treasure. The National Palace was opened to the public in 2008.
Nowadays you can visit 101 rooms (out of 105 rooms) that make-up this masterpiece and look at the colorful floors and walls made out of stamped sheets brought from Belgium.
- Red Room: This room served to hold social and political events. Here are you will see 14 medallions that represent the 14 departments that make up El Salvador. There are also portraits of presidents General Fernando Figueroa, Francisco Morazán, Francisco Menendez, Rafael Campos, Captain Gerardo Barrios and Manuel Enrique Araujo, who after his assassination in 1913,was mourned in this room.
- Pink Room: This is where the Supreme Court met until 1974 and guards the original Salvadoran coat of arms.
- Yellow Room: This room served as the president’s office until 1930, important meetings and negotiations took place in this room.
- Blue Room: perhaps the most important of the rooms as it currently holds the original 28 desks and chairs where the congressmen sat to discuss El Salvador’s legislative matters.
-The Jaguar Hall; has impressive murals depicting indigenous culture themes. Among the many corridors there is a permanent exhibition of photographs which displays the evolution of the building from 1889 onwards.
Inside the Palace there is a central patio with varied vegetation. There are 5 araucaria pine trees representing the five nations of Central America. As part of the restoration process, the original floor of the first building was recovered. There are also three canons used in the war led by Gerardo Barrios.
Currently the Palace is a tourist attraction and a place for special social gatherings. It is under the management of the Ministry of Culture of the Presidency and houses “El Archivo General de la Nación” (National Archives), in addition to carrying-out several exhibitions each year.
Visit this national treasure in the heart of San Salvador and discover a facet of El Salvador’s impressive history.
How to get there:
This National Palace is located on Calle Rubén Darío, across from Plaza Gerardo Barrios, near the Metropolitan Cathedral and The National Library in downtown San Salvador.
If driving there is parking available in The National Library or in the parking lots nearby at US$ 0.50 per hour.
- Bus Routes available: Route A, R-1, 2, Route 6-A, Route 11, 11-B, 11-C, Route 22, Route 23 Route 26.
Ticket US$ 0.20, US$ 0.25, US$ 0.35
Other routes: 3, 9, 34, 38-And, 41-A, 42, 42-A, 42-B.
Ticket US$ 0.20, US$ 0.25, US$ 0.35
• Opening hours: Monday to Friday 8:00 am to 4:00 pm. Admission:
- Salvadoran or Central American US$ 1.00 USD
- Foreign US$ 3.00 USD
- School and university tudents and staff: FREE
• Phone (503) 2222-7674 (503) 2222-9415
Elevation 2203 feet
N 13 ° 41,862 ‘
In 89 ° 11,495 ‘
NOTICEThe information presented in this Promotion Listing Services and destinations of El Salvador is a reference guide. Prices, rates, promotions or details such as the number of people, opening hours, input or output times, meal times, Cymbal ingredients, duration of tours, Sites on tour etc.. and phone numbers, websites or email addresses and physical, and other data can change without prior notice of the hotels, restaurants, Tour operators, inns and other businesses in the tourism industry in this digital catalog. The Ministry of Tourism and the Salvadoran Tourism Coorporación, and its advertising agency and any other company or individual subcontracted for lifting and collection of this information has no responsibility for any variation in the data. It is always suggested to respective queries to verify.
| 3.003419 |
Magnetic Resonance Imaging (MRI)
Magnetic resonance imaging (MRI) is a test that uses a magnetic field and pulses of radio wave energy to make pictures of organs and structures inside the body. In many cases MRI gives different information about structures in the body than can be seen with an X-ray, ultrasound, or computed tomography (CT) scan. MRI also may show problems that cannot be seen with other imaging methods.
For an MRI test, the area of the body being studied is placed inside a special machine that contains a strong magnet. Pictures from an MRI scan are digital images that can be saved and stored on a computer for more study. The images also can be reviewed remotely, such as in a clinic or an operating room. In some cases, contrast material may be used during the MRI scan to show certain structures more clearly.
Why It Is Done
Magnetic resonance imaging (MRI) is done for many reasons. It is used to find problems such as tumors, bleeding, injury, blood vessel diseases, or infection. MRI also may be done to provide more information about a problem seen on an X-ray, ultrasound scan, or CT scan. Contrast material may be used during MRI to show abnormal tissue more clearly. An MRI scan can be done for the:
How To Prepare
Before your MRI test, tell your doctor and the MRI technologist if you:
You may need to arrange for someone to drive you home after the test, if you are given a medicine (sedative) to help you relax.
For an MRI of the abdomen or pelvis, you may be asked to not eat or drink for several hours before the test.
You may need to sign a consent form that says you understand the risks of an MRI and agree to have the test done. Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form(What is a PDF document?).
How It Is Done
A magnetic resonance imaging (MRI) test is usually done by an MRI technologist. The pictures are usually interpreted by a radiologist. But some other types of doctors can also interpret an MRI scan.
You will need to remove all metal objects (such as hearing aids, dentures, jewelry, watches, and hairpins) from your body because these objects may be attracted to the powerful magnet used for the test.
You will need to take off all or most of your clothes, depending on which area is examined (you may be allowed to keep on your underwear if it is not in the way). You will be given a gown to use during the test. If you are allowed to keep some of your clothes on, you should empty your pockets of any coins and cards (such as credit cards or ATM cards) with scanner strips on them because the MRI magnet may erase the information on the cards.
During the test you usually lie on your back on a table that is part of the MRI scanner. Your head, chest, and arms may be held with straps to help you remain still. The table will slide into the space that contains the magnet. A device called a coil may be placed over or wrapped around the area to be scanned. A special belt strap may be used to sense your breathing or heartbeat. This triggers the machine to take the scan at the right time.
Some people feel nervous (claustrophobic) inside the MRI magnet. If this keeps you from lying still, you can be given a medicine (sedative) to help you relax. Some MRI machines (called open MRI) are now made so that the magnet does not enclose your entire body. Open MRI machines may be helpful if you are claustrophobic, but they are not available everywhere. The pictures from an open MRI may not be as good as those from a standard MRI machine. See pictures of a standard MRI machine and an open MRI machine.
Inside the scanner you will hear a fan and feel air moving. You may also hear tapping or snapping noises as the MRI scans are taken. You may be given earplugs or headphones with music to reduce the noise. It is very important to hold completely still while the scan is being done. You may be asked to hold your breath for short periods of time.
During the test, you may be alone in the scanner room. But the technologist will watch you through a window. You will be able to talk with the technologist through a two-way intercom.
If contrast material is needed, the technologist will put it in an intravenous (IV) line in your arm. The material may be given over 1 to 2 minutes. Then more MRI scans are done.
An MRI test usually takes 30 to 60 minutes but can take as long as 2 hours.
How It Feels
You will not have pain from the magnetic field or radio waves used for the MRI test. The table you lie on may feel hard and the room may be cool. You may be tired or sore from lying in one position for a long time.
If a contrast material is used, you may feel some coolness and flushing as it is put into your IV.
In rare cases, you may feel:
There are no known harmful effects from the strong magnetic field used for MRI. But the magnet is very powerful. The magnet may affect pacemakers, artificial limbs, and other medical devices that contain iron. The magnet will stop a watch that is close to the magnet. Any loose metal object has the risk of causing damage or injury if it gets pulled toward the strong magnet.
Metal parts in the eyes can damage the retina. If you may have metal fragments in the eye, an X-ray of the eyes may be done before the MRI. If metal is found, the MRI will not be done.
Iron pigments in tattoos or tattooed eyeliner can cause skin or eye irritation.
An MRI can cause a burn with some medication patches. Be sure to tell your health professional if you are wearing a patch.
There is a slight risk of an allergic reaction if contrast material is used during the MRI. But most reactions are mild and can be treated using medicine. There also is a slight risk of an infection at the IV site.
A magnetic resonance imaging (MRI) is a test that uses a magnetic field and pulses of radio wave energy to make pictures of organs and structures inside the body.
The radiologist may discuss initial results of the MRI with you right after the test. Complete results are usually ready for your doctor in 1 to 2 days.
An MRI can sometimes find a problem in a tissue or organ even when the size and shape of the tissue or organ looks normal.
What Affects the Test
Reasons you may not be able to have the test or why the results may not be helpful include:
Many modern medical devices that do not use electronics—such as heart valves, stents, or clips—can be safely placed in most MRI machines. But some newer MRI machines have stronger magnets. The safety of MRI scans with these stronger MRI magnets in people with medical devices is not known.
What To Think About
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| 3.987497 |
A urinary catheter is a small, flexible tube that can be inserted through the urethra and into the bladder, allowing urine to drain. The urethra is the tube that carries urine outside the body from the bladder.
A urinary catheter may be used for someone who is unable to urinate or who has difficulty moving and getting to the bathroom. It is also used to collect a urine sample from someone who is very ill or unable to provide a clean-catch urine specimen. Catheterization reduces the risk that the sample will be contaminated.
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© 1995-2012 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
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| 3.028429 |
Blood Transfusions for Sickle Cell Disease
During a blood transfusion, a person (the recipient) receives healthy blood from another person (the donor). The donated blood is carefully screened for diseases before it is used. Before receiving a blood transfusion, the recipient's blood is analyzed closely (using blood type) to make sure the donor blood is a close match to the recipient's.
Blood is transfused into an arm vein slowly over 1 to 4 hours (except in an emergency when blood is transfused more quickly).
Blood transfusions can:
What To Expect After Treatment
Following a blood transfusion, doctors keep a close watch on the person for any negative reactions.
Hospital staff will also check for iron buildup in the body (iron overload). This can develop when a person gets many transfusions.
Why It Is Done
A blood transfusion lowers the amount of hemoglobin S red blood cells in the body. When there are fewer sickled hemoglobin S cells in the bloodstream, they are less likely to build up and block blood vessels.
Blood transfusion also increases the number of normal red blood cells in the body, increasing the supply of oxygen to the body.
Some sudden complications of sickle cell disease cause the body's red blood cell count to drop to life-threatening levels (severe anemia). When severe, these conditions (including splenic sequestration, acute chest syndrome, and aplastic crisis) can be fatal if not treated with blood transfusions.
Chronic severe anemia from kidney failure may need treatment with periodic blood transfusions.
After having general anesthesia and surgery, people with sickle cell disease are at risk for sickling-related problems and acute chest syndrome. Blood transfusions before surgery can prevent or treat these complications.
Red blood cell sickling-related complications (vaso-occlusion)
Blood transfusions can treat acute chest syndrome and leg ulcers.
Frequent blood transfusions may help prevent strokes in children who already had a stroke or are at high risk for a first stroke.
How Well It Works
Blood transfusion is an effective and proven treatment for some severe complications of sickle cell disease.1
Blood transfusions reduce the risk of some complications of sickle cell disease and improve symptoms of severe anemia.
A person receiving many blood transfusions will gradually collect too much iron in the body (iron overload). Very high levels of iron can lead to hemochromatosis, which can be fatal if untreated.
After 10 to 20 blood transfusions, iron chelation treatment can help rid the body of excess iron.
A person receiving repeat blood transfusions may develop antibodies to the donor blood. This is called alloimmunization. Alloimmunization makes repeated transfusions more difficult. It occurs in about 1 out of 4 people who have sickle cell disease and who get frequent transfusions.2
A transfusion reaction can result from mismatched blood type. And it may occur immediately or days later (5 to 20 days after transfusion). An acute transfusion reaction ranges from mild (fever, chills, and rash) to severe (shock, severe anemia, painful event, and death).
What To Think About
If you have repeated blood transfusions, you'll have routine testing for iron buildup in your body.
Though blood transfusions are an effective treatment for sickle cell disease complications, they are only used selectively. The risks of hemochromatosis and alloimmunization from repeat transfusions makes this procedure more suitable for severe and high-risk conditions.
Doctors and researchers continue to weigh the benefits against the risks of preventive blood transfusions. Repeat blood transfusion treatment for 3 to 5 years can reduce the number of repeat strokes in children who have sickle cell disease. It helps prevent a second stroke in most children. But some children who get repeat transfusions will still have a second stroke.
eMedicineHealth Medical Reference from Healthwise
To learn more visit Healthwise.org
© 1995-2012 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Find out what women really need.
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| 3.254701 |
Who Is Affected by Raynaud's Phenomenon
Who Is Affected by Raynaud's Phenomenon?
About 10% of people are affected by one of two kinds of Raynaud's phenomenon:1
- Primary Raynaud's (sometimes called Raynaud's disease) has no known cause. It is more common than the secondary form of Raynaud's. It occurs most often in women.
- Secondary Raynaud's (sometimes called Raynaud's syndrome) usually causes more severe symptoms and may develop as the result of other diseases, such as lupus, scleroderma, rheumatoid arthritis, or atherosclerosis. Other causes of secondary Raynaud's include taking certain medicines, using vibrating power tools for several years, smoking, or having frostbite.
Klippel JH (2008). Raynaud phenomenon. In K Wolff et al., eds., Fitzpatrick's Dermatology in General Medicine, 7th ed., vol. 2, pp. 1643–1648. New York: McGraw-Hill.
|Primary Medical Reviewer||Anne C. Poinier, MD - Internal Medicine|
|Specialist Medical Reviewer||Stanford M. Shoor, MD - Rheumatology|
|Last Revised||June 30, 2010|
| 3.056797 |
Click on a thumbnail to see the full-size image
The Story of Why Engine Oil Becomes Engine Sludge
In engines that have failed prematurely, the oil has very often been transformed into a high viscosity deposit of brown or black goo, commonly referred to as "sludge."
By Don Fedak
Fresh engine oil is a clear, free-flowing liquid blend of base stock and
additives that contains no fuel, water, coolant, dirt, or other
When regular engine oil changes are neglected, normally free-flowing lubricating oil breaks down, becomes contaminated, ceases to flow, and is transformed into a thick soup of waste products. That’s when serious engine damage is imminent.
Why does engine oil break down, combine with contaminants, and form sludge deposits? Chemistry teaches that engine oil is unstable and decomposes in the presence of oxygen at high temperature. The process, called oxidation, occurs naturally after exposure to normal operating conditions for extended periods of time and is accelerated by exposure to severe operating conditions or to excessively high temperatures. Alternatively, accelerated oxidation may be triggered by a combination of any or all of these factors.
During oxidation, the chemical bonds that define the oil molecules are broken, and some of the reaction products accumulate and interact to form a highly viscous complex mixture of solids, liquids, and gases that contain a variety of solid carbon-based dirt and metallic particles, as well as liquid coolant, fuel, oil and water droplets.
But what can we possibly learn from a sludged engine?
Consider our reliable 40-year-old 10-hp shop compressor that has delivered zillions of cubic feet of pressurized air daily from its ambient temperature shelter. While the electric motor and the V-belts have been replaced twice, the only other routine service this air-cooled V4 compressor has received, other than having the condensed water drained from the tank, is an occasional oil change. When the used, unfiltered HD-30 oil is drained from its crankcase it shows no evidence of contamination or oxidation and looks like fresh oil.
A typical internal combustion engine is just an air compressor in which fuel is mixed with compressed air and then burned. The combustion process generates heat and a variety of reaction products, some of which enter the crankcase as blow-by and contaminate the oil, e.g., fuel, soot, water and other normal reactants, products and byproducts.
Even though the oil temperature is high enough to boil off and extract all the water and other volatile contaminants via the PCV system, this crankcase broth will inevitably change into a deposit that does not drain when the oil is changed. Air-cooled gas or diesel engines are just air compressors in which the engine oil is subject to oxidation because they are exposed to higher temperatures and contamination by combustion products. If the engine is liquid-cooled, the engine oil may also become contaminated with coolant.
Lesson #1: Sludge deposits in internal combustion engines can indicate either stop-and-go driving, lack of proper maintenance, too low or too high an oil temperature or oil contamination.
Sludge formation is not a new problem. In fact, sludge deposits limited the durability of early internal combustion engines. Over the years, oil base stocks were improved, detergent oil additives were developed to keep microscopic sludge-forming solid particles in suspension, anti-oxidation additives were developed to slow the formation of these sludge deposit precursors, and engine oil filters were fitted to remove suspended solid particles from the oil stream and slow the formation of flow restricting sludge deposits on internal surfaces.
Changes in engine oil formulation and treatment accelerated with the introduction of "permanent" glycol-based coolant, another oil contaminant that may accelerate sludge formation. With the recent increased popularity of wet-sleeved engines, as well as the introduction of alternative but incompatible coolants, we are seeing more engine bearing failures.
Lesson #2: Sludge deposits may be due to inferior oil, deterioration of the oil additives or contamination by coolant.
When "detergent oils" first appeared, everyone’s engine repair business increased. Tired, worn out engines, full of sludge deposits because they had always been serviced with non-detergent oils, were ill advisedly transfused with detergent oil, which promptly attacked the sludge deposits. Engine bearing surfaces were flooded with oil containing a high concentration of newly suspended sludge particles. And during the phase-in of detergent engine oils, a number of chemical elixirs for "engine oil desludging" appeared. With current engines, we often encounter similar failures when engines are accidentally overfilled and loosen normally benign engine deposits. Unless you’re very young or your principal residence is a cave, none of this should be news.
Lesson #3: Absence of sludge deposits may indicate the crankcase has been "flushed," especially if fresh oil contains an excessive concentration of solids.
Some years ago we sold some oil, a filter and a pan gasket for a 366 truck engine to a customer who initially was asked to do a routine oil change. He eventually had to remove the oil pan because the engine oil had thickened and would not flow out of the drain hole. Once he removed the pan bolts, the oil pan, very heavy because it was full of thick black goo, fell to the floor. The bozo who had previously contracted to "service" this fleet vehicle had repeatedly neglected to drain the old oil when he changed the filter and topped up the level of the used oil. Exposed to heat for an extended period of time, the old oil eventually oxidized and transformed into a black mass resembling thick molasses or Le Brea tar pits’ crude.
Lesson #4: Always be suspicious of maintenance information.
Today, we see a lot of sludged engines because of two different factors, the trend to ever-higher engine oil temperatures (oil coolers help) and the tendency to neglect or postpone routine maintenance, especially in the case of leased vehicles. When a yuppy BMW owner volunteered that his "Service Engine" light was designed to indicate when he should add some engine oil, I suggested that he might want to change it to read: "Too Late." Engine noises and low oil pressure are obvious indications of inadequate engine bearing lubrication. So, when oil sludge is also found, overextended drain intervals, elevated oil temperatures and/or contamination should be considered as the most likely causes. But there are always exceptions.
Experienced custom engine builders understand that all sludge deposits are not necessarily due to abuse and neglect. When we find a lot of sludge in an engine, we always try to pinpoint the cause(s), do what we can to avoid a repeat occurrence and advise the customer or the installer how to minimize engine sludge formation.
Today, as in earlier times, new and remanufactured engine durability is directly related to the recognition, control and elimination of all factors that support engine sludge formation including, but not limited to, lack of proper maintenance, inappropriate oil temperature, use of an inferior engine oil, and engine oil contamination.
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| 3.273076 |
The Hebrew Bible is the cornerstone of the Jewish people. Virtually all Jewish creativity refers to this fundamental text, and it has also left its imprint on Christianity and Islam.
The exhibition at the Shrine of the Book Complex represents a journey through time, which, adopting a scholarly-historical approach, traces the evolution of the Book of Books. The upper galleries take the visitor from the oldest extant biblical manuscripts, which were discovered in the Judean Desert, through the story of the sectarians living at Qumran, who attempted to translate the biblical ideals embodied in these texts into a way of life. The lower galleries tell the remarkable tale of the Aleppo Codex – the most accurate manuscript of the Masoretic text and the closest to the text of the printed Hebrew Bibles used today.
Generations of scribes and scholars dedicated themselves to copying the Bible, passing on the traditions related to its reading and cantillation, and interpreting its meaning. Those who cherished it did anything in their power to protect it from harm, at times even enduring martyrdom for its sake. Though the motivation for this esteem, which continues until the present day, may take different forms – belief in the divine origins of the biblical text, admiration for the profundity of its ideas, or acknowledgement of its historical cultural importance – one thing remains clear: as long as people continue to inquire about the nature of life and the world in which we live, the Bible will continue to inspire creativity, comfort the troubled, and provide hope for individuals wherever they may be.
The Shrine of the Book was built as a repository for the first seven scrolls discovered at Qumran in 1947. This symbolic building, a kind of sanctuary intended to express profound spiritual meaning, is considered an international landmark of modern architecture. Designed by American Jewish architects Armand P. Bartos and Frederic J. Kiesler, it was dedicated in an impressive ceremony on April 20, 1965. Its location next to official institutions of the State of Israel – the Knesset (Israeli Parliament), key government offices, and the Jewish National and University Library – attests to the degree of national importance that has been accorded the ancient texts and the building that preserves them.
The white dome symbolizes the lids of the jars in which the first scrolls were found; the contrast between the white dome and the black wall alongside it alludes to the tension evident in the scrolls between the spiritual world of the “Sons of Light” (as the Judean Desert sectarians called themselves) and the “Sons of Darkness” (the sect’s enemies). The corridor leading into the Shrine resembles a cave, recalling the site where the ancient manuscripts were discovered.
| 3.303912 |
Here, now, are two great whales, laying their heads together; let us join them, and lay together our own.
Of the grand order of folio leviathans, the Sperm Whale and the Right Whale are by far the most noteworthy. They are the only whales regularly hunted by man. To the Nantucketer, they present the two extremes of all the known varieties of the whale. As the external difference between them is mainly observable in their heads; and as a head of each is this moment hanging from the Pequod's side; and as we may freely go from one to the other, by merely stepping across the deck:--where, I should like to know, will you obtain a better chance to study practical cetology than here?
In the first place, you are struck by the general contrast between these heads. Both are massive enough in all conscience; but there is a certain mathematical symmetry in the Sperm Whale's which the Right Whale's sadly lacks. There is more character in the Sperm Whale's head. As you behold it, you involuntarily yield the immense superiority to him, in point of pervading dignity. In the present instance, too, this dignity is heightened by the pepper and salt colour of his head at the summit, giving token of advanced age and large experience. In short, he is what the fishermen technically call a "grey-headed whale."
Let us now note what is least dissimilar in these heads--namely, the two most important organs, the eye and the ear. Far back on the side of the head, and low down, near the angle of either whale's jaw, if you narrowly search, you will at last see a lashless eye, which you would fancy to be a young colt's eye; so out of all proportion is it to the magnitude of the head.
Now, from this peculiar sideway position of the whale's eyes, it is plain that he can never see an object which is exactly ahead, no more than he can one exactly astern. In a word, the position of the whale's eyes corresponds to that of a man's ears; and you may fancy, for yourself, how it would fare with you, did you sideways survey objects through your ears. You would find that you could only command some thirty degrees of vision in advance of the straight side-line of sight; and about thirty more behind it. If your bitterest foe were walking straight towards you, with dagger uplifted in broad day, you would not be able to see him, any more than if he were stealing upon you from behind. In a word, you would have two backs, so to speak; but, at the same time, also, two fronts (side fronts): for what is it that makes the front of a man--what, indeed, but his eyes?
Moreover, while in most other animals that I can now think of, the eyes are so planted as imperceptibly to blend their visual power, so as to produce one picture and not two to the brain; the peculiar position of the whale's eyes, effectually divided as they are by many cubic feet of solid head, which towers between them like a great mountain separating two lakes in valleys; this, of course, must wholly separate the impressions which each independent organ imparts. The whale, therefore, must see one distinct picture on this side, and another distinct picture on that side; while all between must be profound darkness and nothingness to him. Man may, in effect, be said to look out on the world from a sentry-box with two joined sashes for his window. But with the whale, these two sashes are separately inserted, making two distinct windows, but sadly impairing the view. This peculiarity of the whale's eyes is a thing always to be borne in mind in the fishery; and to be remembered by the reader in some subsequent scenes.
A curious and most puzzling question might be started concerning this visual matter as touching the Leviathan. But I must be content with a hint. So long as a man's eyes are open in the light, the act of seeing is involuntary; that is, he cannot then help mechanically seeing whatever objects are before him. Nevertheless, any one's experience will teach him, that though he can take in an undiscriminating sweep of things at one glance, it is quite impossible for him, attentively, and completely, to examine any two things--however large or however small--at one and the same instant of time; never mind if they lie side by side and touch each other. But if you now come to separate these two objects, and surround each by a circle of profound darkness; then, in order to see one of them, in such a manner as to bring your mind to bear on it, the other will be utterly excluded from your contemporary consciousness. How is it, then, with the whale? True, both his eyes, in themselves, must simultaneously act; but is his brain so much more comprehensive, combining, and subtle than man's, that he can at the same moment of time attentively examine two distinct prospects, one on one side of him, and the other in an exactly opposite direction? If he can, then is it as marvellous a thing in him, as if a man were able simultaneously to go through the demonstrations of two distinct problems in Euclid. Nor, strictly investigated, is there any incongruity in this comparison.
It may be but an idle whim, but it has always seemed to me, that the extraordinary vacillations of movement displayed by some whales when beset by three or four boats; the timidity and liability to queer frights, so common to such whales; I think that all this indirectly proceeds from the helpless perplexity of volition, in which their divided and diametrically opposite powers of vision must involve them.
But the ear of the whale is full as curious as the eye. If you are an entire stranger to their race, you might hunt over these two heads for hours, and never discover that organ. The ear has no external leaf whatever; and into the hole itself you can hardly insert a quill, so wondrously minute is it. It is lodged a little behind the eye. With respect to their ears, this important difference is to be observed between the sperm whale and the right. While the ear of the former has an external opening, that of the latter is entirely and evenly covered over with a membrane, so as to be quite imperceptible from without.
Is it not curious, that so vast a being as the whale should see the world through so small an eye, and hear the thunder through an ear which is smaller than a hare's? But if his eyes were broad as the lens of Herschel's great telescope; and his ears capacious as the porches of cathedrals; would that make him any longer of sight, or sharper of hearing? Not at all.--Why then do you try to "enlarge" your mind? Subtilize it.
Let us now with whatever levers and steam-engines we have at hand, cant over the sperm whale's head, that it may lie bottom up; then, ascending by a ladder to the summit, have a peep down the mouth; and were it not that the body is now completely separated from it, with a lantern we might descend into the great Kentucky Mammoth Cave of his stomach. But let us hold on here by this tooth, and look about us where we are. What a really beautiful and chaste-looking mouth! from floor to ceiling, lined, or rather papered with a glistening white membrane, glossy as bridal satins.
But come out now, and look at this portentous lower jaw, which seems like the long narrow lid of an immense snuff-box, with the hinge at one end, instead of one side. If you pry it up, so as to get it overhead, and expose its rows of teeth, it seems a terrific portcullis; and such, alas! it proves to many a poor wight in the fishery, upon whom these spikes fall with impaling force. But far more terrible is it to behold, when fathoms down in the sea, you see some sulky whale, floating there suspended, with his prodigious jaw, some fifteen feet long, hanging straight down at right-angles with his body, for all the world like a ship's jib-boom. This whale is not dead; he is only dispirited; out of sorts, perhaps; hypochondriac; and so supine, that the hinges of his jaw have relaxed, leaving him there in that ungainly sort of plight, a reproach to all his tribe, who must, no doubt, imprecate lock-jaws upon him.
In most cases this lower jaw--being easily unhinged by a practised artist--is disengaged and hoisted on deck for the purpose of extracting the ivory teeth, and furnishing a supply of that hard white whalebone with which the fishermen fashion all sorts of curious articles, including canes, umbrella-stocks, and handles to riding-whips.
With a long, weary hoist the jaw is dragged on board, as if it were an anchor; and when the proper time comes--some few days after the other work--Queequeg, Daggoo, and Tashtego, being all accomplished dentists, are set to drawing teeth. With a keen cutting-spade, Queequeg lances the gums; then the jaw is lashed down to ringbolts, and a tackle being rigged from aloft, they drag out these teeth, as Michigan oxen drag stumps of old oaks out of wild wood lands. There are generally forty-two teeth in all; in old whales, much worn down, but undecayed; nor filled after our artificial fashion. The jaw is afterwards sawn into slabs, and piled away like joists for building houses.
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Test Your Knowledge
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Studies suggest that only 31% of Europe is thought to have a water supply that is either plentiful or sufficient to meet demands until 2015, and water stress indexes show a number of countries with traditionally wet climates such as Belgium and Bulgaria, under significant water stress. Therefore, there is both a desire and a need to reduce the consumption of water over much of Europe. For industry, often economics determine the viability of water recycling, which does not necessarily fall under the standards currently being set for the major water reuse schemes. While the additional annual recycling capacity in Western Europe is set to increase by 10%, much of the Global market is focussed on major reuse facilities based on the municipal sector. Within the industrial sector there are opportunities to achieve major changes in the water cycle which can have a significant impact on total water consumption. The impact on regional water consumption by industries efforts can be massive, as industry accounts for 50% of the water consumption in Western Europe. When benchmarked data across industry sectors is analysed, we find that industries ranging from paper mills, dairy, beverage, ceramic and electronics have opportunities to reduce their water consumption by around 50%. But what are the mechanisms that drive actions in the industry water cycle, and how great can the impact be? This paper explores industrial water costs across Europe, and the drivers leading to reduced water consumption. As operators of water and wastewater facilities for many industrial customers across Europe, Ondeo Industrial Solutions examine the raw water costs and the viability of recycle schemes. Economics is not the only driver towards the reduction in water consumption on industrial sites. There are political and legislative drivers that can often override the economics such as the European PPC (Pollution Prevention and Control) directive that can often lead to a programme of water consumption reductions.
Water Science and Technology: Water Supply is published as an adjunct to Water Science and Technology, in 6 issues per year, covering new developments in water supply. Papers are selected by a rigorous peer review procedure and the journal publi » Read more
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A diverse fauna is also found in this relatively high rainfall region.
However, the region around Perth is heavily developed and much of this region has already been cleared. While there are several large protected areas in the region, continued development, habitat fragmentation, dieback disease, and inappropriate fire regimes are serious threats.
Location and General Description
South of Perth down to Cape Naturaliste, the Swan Coastal Plain forms a low-lying belt 25 kilometers (km) to 30 km wide, bordered to the east by the Darling Scarp and the Precambrian Yilgarn Block. The Swan Coastal Plain is covered by shoreline and associated dune deposits from the Pleistocene and Holocene that overlie Paleozoic and Neogene deposits of the Perth Basin. The Plain also includes large microtidal estuarine systems, such as the Swan-Canning Estuary and a number of lakes cut off from the sea by barrier dunes. The Swan Coastal Plain is transected by rivers flowing west from the Darling Plateau, and interspersed by wetlands.
Progressing inland from the coast, coastal dunes with scrub-heath communities give way to woodlands. Kwongan (an Aboriginal term for heath-like vegetation), eucalypt, and Banksia low woodlands occur on the soils of the coastal dunes. Generally, kwongan scrub heath grows on sandy plains and swales and on lateritic upland soils while mallee eucalyptus woodland grows on duplex soils of upper valley slopes. Open heath favors drier areas, while a better water table allows the development of eucalypt shrubs. Scrub-heath species include Banksia attenuata and B. menziesii with Casuarina spp. and E. todtiana. Christmas trees (Nuytsia floribunda) become locally dominant in drier areas. Shrubs are present, largely in wetter areas, with Acacia, Adenanthos, Banksia, Casuarina, Dryandra, Grevillea, and Hakea species found here.
Eucalypt woodlands can be found on the sandy loams, loams, and heavy loams on lower slopes and valley floors. Tall tuart (Eucalyptus gomphocephala) forests grow at the southern end of the Swan Coastal Plain. Tuart usually occurs in monospecific stands, but can also be found with E. decipiens and/or E. cornuta. In the south, pure stands grow with peppermint (Agonis flexuosa), while in the north, peppermint is replaced by small Banksia trees and Casuarina fraserana. Now largely cleared, marri (Eucalyptus calophylla)–kingia (Kingia australis) woodlands grow on heavy soils of the Swan Coastal Plain, and marri–grass tree (Xanthorrhoea preissii) woodlands and shrublands also grow on the Swan Coastal Plain.
Western Australia contains approximately 12,000 angiosperms (half of Australia's total flora), 75 percent of which are endemic to the southwestern region. The southwestern Mediterranean climate regions are estimated to contain 8,000 species, with three quarters endemic. Finally, the Swan Coastal Plain is estimated to contain more than 2,000 species. Several large genera, such as Banksia, Caladenia, and Leucopogon, have the centers of their distribution in the Mediterranean climate, southwestern region. Other genera are wholly restricted to the southwestern region, including Dryandra and Synaphea. Endemism is highest at the species level, and there are few endemic plant families.
Mediterranean-climate vegetation shows a variety of adaptations to the poor soils, summer drought, and fires. The Christmas tree is a root parasite, the only member of the Mistletoe family to grow as a tree. Three quarters of the world's carnivorous Drosera species are found in Western Australia, many of them in the kwongan and sandplain heaths, obtaining nitrogen and phosphorus from the insects they capture. Also noteworthy, approximately 15 percent of southwestern wildflowers are vertebrate pollinated. Vertebrate pollinators include the western pygmy possum (Cercartetus concinnus) and honey possums (Tarsipes rostratus), the only mammal apart from some bats to subsist entirely on nectar and pollen.
Other mammals found in this ecoregion include tammar wallabies (Macropus eugenii), which were widely distributed in this ecoregion prior to European settlement, but remain offshore on Garden Island. In Western Australia the tammar wallaby lives among bushes of Gastrolobium bilobum, a fire-dependent, nitrogen-fixing legume that allows the growth of grasses, which are rare in the southwestern forested regions. Tammar wallabies feed on these grasses. Rottnest Island lies 18 kilometers (km) offshore of Perth and harbors a stable population of quokkas (Setonix brachyurus VU), probably because there are no foxes. Heathland and wildflower habitats contain a rich avifauna, especially among the honey-eaters. Other birds found in this ecoregion include the western thornbill (Acanthiza inornata), and the short-billed black-cockatoo (Calyptorhynchus latirostris EN) which inhabits sandplain woodlands and mallee, and the long-billed black-cockatoo (Calyptorhynchus baudinii) which is found in open eucalypt woodland and farmland.
Seasonal wetlands (dry in the summer and wet in winter) are the most diverse habitat on the Swan Coastal Plain, and 16 out of 30 major floristic communities occur in wetlands. Coastal and near-coastal areas the next richest, containing 7 major communities. The junction between the Swan Coastal Plain and the Darling Scarp is biologically diverse with relatively fertile soils, granite outcrops, and unusual clay-based ephemeral swamps. These swamps provide habitat for the critically endangered western swamp tortoise (Pseudemydura umbrina) which is found only in this ecoregion and may be Australia's rarest reptile. It appears to be restricted to shallow, ephemeral swamps over the clay soils of the Swan River Valley. The region around Perth is known for a diverse herpetofauna, including 16 frogs, two freshwater turtles, 51 lizards, and 24 snakes.
Nearly 80 percent of the Swan Coastal Plain has been cleared. Sandplain heathlands near Perth have almost entirely been converted as the urban center expands. Urban expansion reaches as far east as the Darling Scarp and has spread in a north-south direction as well.
A number of Swan Coastal Plain woodland communities are listed as Endangered under the Commonwealth Environment Protection and Biodiversity Conservation Act: marri (Eucalyptus calophylla)–kingia (Kingia australis) woodlands on heavy soils, marri (Eucalyptus calophylla)–grass tree (Xanthorrhoea preissii) woodlands, and shrublands, shrublands, and woodlands of the eastern Swan Coastal Plain, shrublands and woodlands on Muchea Limestone of the Swan Coastal Plain, and shrublands and woodlands on Perth to Gingin ironstone.
Protected areas in this ecoregion include the Hills Forest conservation area which comprises five national parks (John Forrest, Gooseberry Hill, Greenmount, Kalamunda, and Lesmurdie Falls) and the Mount Dale Conservation Park. This ecoregion has a lower percentage of land in protected areas than the Jarrah-Karri forest and shrublands and Southwest Australia woodlands ecoregions.
Types and Severity of Threats
Continuing urban expansion and human use are severe threats. Proteaceae are susceptible to dieback disease caused by Phytophthora spp, and its spread through the wildflower heathlands is a serious concern. Too frequent fires may significantly alter plant species distributions. Fires poses a different threat on the coastal plain than they do in forests; on the coastal plain they are commonly the agent for woodland invasion by weeds.
Justification of Ecoregion Delineation
This ecoregion occupies the Swan Coastal Plain, bounded by the ocean to the west and by the Yilgarn Block to the east. It has the same boundary as the 'Swan Coastal Plain' Interim Biogeographic Region of Australia (IBRA).
Additional Information on this Ecoregion
- For a shorter summary of this entry, see the WWF WildWorld profile of this ecoregion.
- To see the species that live in this ecoregion, including images and threat levels, see the WWF Wildfinder description of this ecoregion.
- World Wildlife Fund Homepage
- Beadle, N. C. W. 1981. The Vegetation of Australia. Cambridge University Press, Cambridge, United Kingdom. ISBN: 0521241952
- Beard, J. S. 1995. South-west Botanical Province. Pages 484–489 in S. D. Davis, V. H. Heywood and A. C. Hamilton. editors. Centres of Plant Diversity. Volume 2. Asia, Australasia, and the Pacific. WWF/IUCN, IUCN Publications Unit, Cambridge, UK. ISBN: 2831701988
- Cogger, H., E. Cameron, R. Sadlier, and P. Eggler. 1993. The action plan for Australian reptiles. Australian Nature Conservation Agency. Sydney, Australia.
- Environment Australia. 2001. Land management: firewood, woodlands. Department of the Environment and Water Resources. Viewed on October 10, 2001.
- Hilton-Taylor, C. 2000. The IUCN 2000 Red List of Threatened Species. IUCN, Gland, Switzerland and Cambridge, United Kingdom. ISBN: 2831705657
- Hopper, S. D., M. S. Harvey, J. A. Chappill, A. R. Main, and B. Y. Main. 1996. The western Australian biota as Gondwanan heritage – a review. Pages 1-46 in S. D. Hopper, J. A. Chappill, M. S. Harvey, and A. S. George, editors. Gondwanan Heritage: past, present, and future of the western Australian biota. Surrey Beatty & Sons, Chipping Norton, Australia. ISBN: 0949324663
- Johnson, B. and C. Thomson. 1996. Mammals of the South-West. Department of Conservation and Land Management, Como, Western Australia, Australia.
- Thackway, R. and I. D. Cresswell. editors. 1995. An Interim Biogeographic Regionalisation for Australia: A Framework for Setting Priorities in the National Reserves System Cooperative Program. Australian Nature Conservation Agency, Canberra.
- Wardell-Johnson, G. and P. Horwitz. 1996. Conserving biodiversity and the recognition of heterogeneity in ancient landscapes: a case study from south-western Australia. Forest Ecology and Management 85: 219–238.
- Wisheu, I. C., M. L. Rosenzweig, L. Olsvig-Whittaker, and A. Shmida. 2000. What makes nutrient-poor mediterranean heathlands so rich in plant diversity? Evolutionary Ecology Research 2: 935–955.
- White, M. E. 1994. After the Greening: the browning of Australia. Kangaroo Press, Kenthurst, New South Wales, Australia. ISBN: 086417585X
- Yates, C. J., R. J. Hobbs, and D. T. True. 2000. The distribution and status of eucalypt woodlands in Western Australia. Pages 86–106 in R. J. Hobbs and C. J. Yates. editors. Temperate Eucalypt Woodlands in Australia: biology, conservation, management, and restoration. Surrey Beatty & Sons, Chipping Norton, Australia. ISBN: 0949324868
Disclaimer: This article is taken wholly from, or contains information that was originally published by, the World Wildlife Fund. Topic editors and authors for the Encyclopedia of Earth may have edited its content or added new information. The use of information from the World Wildlife Fund should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content.
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An earthquake is a sudden vibration or trembling in the Earth. More than 150,000 tremors strong enough to be felt by humans occur each year worldwide (see Chance of an Earthquake). Earthquake motion is caused by the quick release of stored potential energy into the kinetic energy of motion. Most earthquakes are produced along faults, tectonic plate boundary zones, or along the mid-oceanic ridges (Figures 1 and 2).
Figure 1: Distribution of earthquake epicenters from 1975 to 1995. Depth of the earthquake focus is indicated by color. Deep earthquakes occur in areas where oceanic crust is being actively subducted. About 90% of all earthquakes occur at a depth between 0 and 100 kilometers. (Source: U.S. Geologic Survey, National Earthquake Information Center)
Figure 2: Distribution of earthquakes with a magnitude less than 5.0 relative to the various tectonic plates found on the Earth's surface. Each tectonic plate has been given a unique color. This illustration indicates that the majority of small earthquakes occur along plate boundaries. (Source: PhysicalGeography.net)
At these areas, large masses of rock that are moving past each other can become locked due to friction. Friction is overcome when the accumulating stress has enough force to cause a sudden slippage of the rock masses. The magnitude of the shock wave released into the surrounding rocks is controlled by the quantity of stress built up because of friction, the distance the rock moved when the slippage occurred, and ability of the rock to transmit the energy contained in the seismic waves. The San Francisco earthquake of 1906 involved a six meter horizontal displacement of bedrock. Sometime after the main shock wave, aftershocks can occur because of the continued release of frictional stress. Most aftershocks are smaller than the main earthquake, but they can still cause considerable damage to already weakened natural and human-constructed features. Earthquakes that occur under or near bodies of water can give rise to tsunamis, which in cases like the December 26, 2004 Sumatra-Andaman Island earthquake reult in far greater distruction and loss of life that the initial earthquake.
Earthquakes are a form of wave energy that is transferred through bedrock. Motion is transmitted from the point of sudden energy release, the earthquake focus (hypocenter), as spherical seismic waves that travel in all directions outward (Figure 3). The point on the Earth's surface directly above the focus is termed the epicenter. Two different types of seismic waves have been described by geologists: body waves and surface waves. Body waves are seismic waves that travel through the lithosphere. Two kinds of body waves exist: P-waves and S-waves. Both of these waves produce a sharp jolt or shaking. P-waves or primary waves are formed by the alternate expansion and contraction of bedrock and cause the volume of the material they travel through to change. They travel at a speed of about 5 to 7 kilometers per second through the lithosphere and about 8 kilometers per second in the asthenosphere. The speed of sound is about 0.30 kilometers per second. P-waves also have the ability to travel through solid, liquid, and gaseous materials. When some P-waves move from the ground to the lower atmosphere, the sound wave that is produced can sometimes be heard by humans and animals.
Figure 3: Movement of body waves away from the focus of the earthquake. The epicenter is the location on the surface directly above the earthquake's focus. (Source: PhysicalGeography.net)
S-waves or secondary waves are a second type of body wave. These waves are slower than P-waves and can only move through solid materials. S-waves are produced by shear stresses and move the materials they pass through in a perpendicular (up and down or side to side) direction.
Surface waves travel at or near the Earth's surface. These waves produce a rolling or swaying motion causing the Earth's surface to behave like waves on the ocean. The velocity of these waves is slower than body waves. Despite their slow speed, these waves are particularly destructive to human construction because they cause considerable ground movement.
Earthquake Magnitude and Energy
|Table 1: Relationship between Richter Scale magnitude and energy released.|
|2.0||1.3 x 108||Smallest earthquake detectable by people.|
|5.0||2.8 x 1012||Energy released by the Hiroshima atomic bomb.|
|6.0 - 6.9||7.6 x 1013 to 1.5 x 1015||
About 120 shallow earthquakes of this magnitude
occur each year on the Earth.
|6.7||7.7 x 1014||Northridge, California earthquake January 17, 1994.|
|7.0||2.1 x 1015||Major earthquake threshold. Haiti earthquake of January 12, 2010 resulted in an estmated 222,570 deaths|
|7.4||7.9 x 1015||Turkey earthquake August 17, 1999. More than 12,000 people killed.|
|7.6||1.5 x 1016||Deadliest earthquake in the last 100 years. Tangshan, China, July 28, 1976. Approximately 255,000 people perished.|
|8.3||1.6 x 1017||San Francisco earthquake of April 18, 1906.|
|9.0||Japan Earthquake March 11, 2011|
|9.1||4.3 x 1018||December 26, 2004 Sumatra earthquake which triggered a tsunami and resulted in 227,898 deaths spread across fourteen countries|
|9.5||8.3 x 1018||Most powerful earthquake recorded in the last 100 years. Southern Chile on May 22, 1960. Claimed 3,000 lives.|
The strength of an earthquake can be measured by a device called a seismograph. When an earthquake occurs this device converts the wave energy into a standard unit of measurement like the Richter scale. In the Richter scale, units of measurement are referred to as magnitudes. The Richter scale is logarithmic. Thus, each unit increase in magnitude represents 10 times more energy released. Table 1 describes the relationship between Richter scale magnitude and energy released. The following equation can be used to approximate the amount of energy released from an earthquake in joules when Richter magnitude (M) is known:
Energy in joules = 1.74 x 10(5 + 1.44*M)
Figures 4 and 5 describe the spatial distribution of small and large earthquakes respectively. These maps indicate that large earthquakes have distributions that are quite different from small events. Many large earthquakes occur some distance away from a plate boundary. Some geologists believe that these powerful earthquakes may be occurring along ancient faults that are buried deep in the continental crust. Recent seismic studies in the central United States have discovered one such fault located thousands of meters below the lower Mississippi Valley. Some large earthquakes occur at particular locations along the plate boundaries. Scientists believe that these areas represent zones along adjacent plates that have greater frictional resistance and stress.
Figure 4: Distribution of earthquakes with a magnitude less than 5 on the Richter Scale. (Image Source: PhysicalGeography.net)
Figure 5: Distribution of earthquakes with a magnitude greater than 7 on the Richter Scale. (Image Source: PhysicalGeography.net)
The Richter Scale Magnitude, while the most known, is one of several measures of the magnitude of an earthquake. The most commonly used are:
- Local magnitude (ML), commonly referred to as "Richter magnitude;"
- Surface-wave magnitude (Ms);
- Body-wave magnitude (Mb); and
- Moment magnitude (Mw).
Scales 1 to 3 have limited range and applicability and do not satisfactorily measure the size of the largest earthquakes. The moment magnitude (Mw) scale, based on the concept of seismic moment, is uniformly applicable to all sizes of earthquakes but is more difficult to compute than the other types. All magnitude scales should yield approximately the same value for any given earthquake.
The severity of an earthquake can be expressed in terms of both intensity and magnitude. However, the two terms are quite different, and they are often confused.
Intensity is based on the observed effects of ground shaking on people, buildings, and natural features. It varies from place to place within the disturbed region depending on the location of the observer with respect to the earthquake epicenter while magnitude is related to the amount of seismic energy released at the hypocenter of the earthquake.
Although numerous intensity scales have been developed over the last several hundred years to evaluate the effects of earthquakes, the one currently used in the United States is the Modified Mercalli (MM) Intensity Scale. The lower numbers of the intensity scale generally deal with the manner in which the earthquake is felt by people. The higher numbers of the scale are based on observed structural damage. Structural engineers usually contribute information for assigning intensity values of Vlll or above.
The following is an abbreviated description of the 12 levels of Modified Mercalli intensity.
I. Not felt except by a very few under especially favorable conditions.
II. Felt only by a few persons at rest, especially on upper floors of buildings. Delicately suspended objects may swing.
III. Felt quite noticeably by persons indoors, especially on upper floors of buildings. Many people do not recognize it as an earthquake. Standing motor cars may rock slightly. Vibration similar to the passing of a truck. Duration estimated.
IV. Felt indoors by many, outdoors by few during the day. At night, some awakened. Dishes, windows, doors disturbed; walls make cracking sound. Sensation like heavy truck striking building. Standing motor cars rocked noticeably.
V. Felt by nearly everyone; many awakened. Some dishes, windows broken. Unstable objects overturned. Pendulum clocks may stop.
Vl. Felt by all, many frightened. Some heavy furniture moved; a few instances of fallen plaster. Damage slight.
Vll. Damage negligible in buildings of good design and construction; slight to moderate in well-built ordinary structures; considerable damage in poorly built or badly designed structures; some chimneys broken.
Vlll. Damage slight in specially designed structures; considerable damage in ordinary substantial buildings with partial collapse. Damage great in poorly built structures. Fall of chimneys, factory stacks, columns, monuments, walls. Heavy furniture overturned.
IX. Damage considerable in specially designed structures; well-designed frame structures thrown out of plumb. Damage great in substantial buildings, with partial collapse. Buildings shifted off foundations.
X. Some well-built wooden structures destroyed; most masonry and frame structures destroyed with foundations. Rails bent.
Xl. Few, if any (masonry) structures remain standing. Bridges destroyed. Rails bent greatly.
Xll. Damage total. Lines of sight and level are distorted. Objects thrown into the air.
Earthquake Damage and Destruction
Earthquakes are a considerable hazard to humans. Earthquakes can cause destruction by structurally damaging buildings and dwellings, fires, tsunamis, and mass wasting (see Figures 6 to 10). Earthquakes can also take human lives. The amount of damage and loss of life depends on a number of factors. Some of the more important factors are:
- Time of day. Higher losses of life tend to occur on weekdays between the hours of 9:00 AM to 4:00 PM. During this time interval many people are in large buildings because of work or school. Large structures are often less safe than smaller homes in an earthquake.
- Magnitude of the earthquake and duration of the event.
- Distance form the earthquake's focus. The strength of the shock waves diminish with distance from the focus.
- Geology of the area affected and soil type. Some rock types transmit seismic wave energy more readily. Buildings on solid bedrock tend to receive less damage. Unconsolidated rock and sediments have a tendency to increase the amplitude and duration of the seismic waves increasing the potential for damage. Some soil types when saturated become liquefied (Figure 6).
- Type of building construction. Some building materials and designs are more susceptible to earthquake damage (Figure 7).
- Population density. More people often means greater chance of injury and death.
The greatest loss of life because of an earthquake this century occurred in Tangshan, China in 1976 when an estimated 250,000 people died. In 1556, a large earthquake in the Shanxi Province of China was estimated to have caused the death of about 1,000,000 people.
A common problem associated with earthquakes in urban areas is fire (Figure 8). Shaking and ground displacement often causes the severing of electrical and gas lines leading to the development of many localized fires. Response to this problem is usually not effective because shock waves also rupture pipes carrying water. In the San Francisco earthquake of 1906, almost 90% of the damage to buildings was caused by fire.
In mountainous regions, earthquake-provoked landslides can cause many deaths and severe damage to built structures (Figure 9). The town of Yungay, Peru was buried by a debris flow that was triggered by an earthquake that occurred on May 31, 1970. This disaster engulfed the town in seconds with mud, rock, ice, and water and took the lives of about 20,000 people.
Another consequence of earthquakes is the generation of tsunamis (Figure 10). Tsunamis, or tidal waves, form when an earthquake triggers a sudden movement of the seafloor. This movement creates a wave in the water body which radiates outward in concentric shells. On the open ocean, these waves are usually no higher than one to three meters in height and travel at speed of about 750 kilometers per hour. Tsunamis become dangerous when they approach land. Frictional interaction of the waves with the ocean floor, as they near shore, causes the waves to slow down and collide into each other. This amalgamation of waves then produces a super wave that can be as tall as 65 meters in height.
The US Geological Survey estimate that at least 1,783 deaths worldwide resulted from earthquake activity in 2009. In 2010, the number rose to 226,729 as the result of 222,570 people killed by the Jauary 12, 2010 earthquake in Haiti.
The deadliest earthquake of 2009 was a magnitude 7.5 event that killed approximately 1,117 people in southern Sumatra, Indonesia on Sept. 30, according to the U.S. Geological Survey (USGS) and confirmed by the United Nations Office for Coordination of Humanitarian Affairs (OCHA). However, the number of earthquake-related fatalities in 2009 was far less than the 2008 count of over 88,000. The high number of fatalities in 2008 was primarily due to the devastating magnitude 7.9 earthquake that occurred in Sichuan, China on May 12.
Although unrelated, the Sept. 30 Indonesian earthquake occurred a day after the year’s strongest earthquake, a magnitude 8.1 on Sept. 29 in the Samoa Islands region. Tsunamis generated by that earthquake killed 192 people in American Samoa, Samoa and Tonga. A magnitude 6.3 earthquake hit the medieval city of L’Aquila in central Italy on April 6, killing 295 people.
Overall, earthquakes took the lives of people in 15 countries on four continents during 2009, including Afghanistan, Bhutan, China, Costa Rica, Greece, Indonesia, Italy, Kazakhstan, Honduras, Japan, Malawi, Samoa, South Africa and Tonga, as well as the U.S. territory of American Samoa. Earthquakes injured people in 11 additional countries, including the mainland United States, where a magnitude 4.4 earthquake on May 2 injured one person in the Los Angeles area.
The biggest 2009 earthquake in the 50 United States was in the Aleutian Islands of Alaska. The magnitude 6.5 earthquake occurred in the Fox Islands on Oct. 13. It was felt at the towns of Akutan and Unalaska, but caused no casualties or damage. The greatest earthquake for the year in the contiguous United States was a magnitude 5.2 event on October 2 in the Owens Valley southeast of Lone Pine, California. Because of the sparse population in the epicentral area, this quake caused no damage although it was felt as far away as Merced and Los Angeles, California and Las Vegas, Nevada.
A magnitude 9.1 Sumatra-Andaman Island earthquake and subsequent tsunami on December 26, 2004 killed 227,898 people, which is the fourth largest casualty toll for earthquakes and the largest toll for a tsunami in recorded history. As a consequence of that earthquake, the USGS has significantly improved its earthquake notification and response capabilities. Improvements include the addition of nine real-time seismic stations across the Caribbean basin, a seismic and tsunami prone region near the U.S. southern border, implementation of a 24x7 earthquake operations center at the USGS National Earthquake Information Center (NEIC), and development of innovative tools for rapid evaluation of population exposure and damage to potentially damaging earthquakes.
The USGS estimates that several million earthquakes occur throughout the world each year, although most go undetected because they hit remote areas or have very small magnitudes. The USGS NEIC publishes the locations for about 40 earthquakes per day, or about 14,500 annually, using a publication threshold of magnitude 4.5 or greater worldwide or 2.5 or greater within the United States. On average, only 18 of these earthquakes occur at a magnitude of 7.0 or higher each year.
In the 2009 year, 17 earthquakes reached a magnitude of 7.0 or higher, with a single one topping a magnitude of 8.0. These statistics for large magnitude earthquakes are higher than those of 2008, which experienced only 12 earthquakes over magnitude 7.0 and none over 8.0. Factors such as the size of an earthquake, the location and depth of the earthquake relative to population centers, and fragility of buildings, utilities and roads all influence how earthquakes will affect nearby communities.
Table 2. Notable Earthquakes and Their Estimated Magnitude
|January 23, 1556||
|August 17, 1668||
|November 1, 1755||
|December 16, 1857||
|October 27, 1891||
|June 15, 1896||
|April 18, 1906||3,000||7.8|
|August 17, 1906||
|December 28, 1908||
|December 16, 1920||
|September 1, 1923||
|May 22, 1927||
|January 13, 1934||
|December 26, 1939||
|February 29, 1960||
|May 22, 1960||
|March 28, 1964||
Prince William Sound, AK
|May 31, 1970||
|July 27, 1976||
|September 19, 1985||
|December 7, 1988||
|August 17, 1999||
|January 26, 2001||
|December 26, 2003||
|December 26, 2004||
Off west coast northern Sumatra
|October 8, 2005||
|May 26, 2006||
|May 12, 2008||
Eastern Sichuan, China
|January 12, 2010||
Near Port-au-Prince, Haiti
|March 11, 2011||
Pacific Ocean, East of Oshika Peninsula, Japan
* Fatalities in the 1976 Tangshan, China earthquake were estimated as high as 655,000.
Source: Preferred Magnitudes of Selected Significant Earthquakes, USGS, 2010 (with additions on two most recent major earthquakes in Haiti and Japan.
The following links provide some more information about earthquakes.
- American Geophysical Union (AGU)
- Animation of P, S & Surface Waves
- Animations of Seismology Fundamentals
- Association of American State Geologists (AASG)
- Association of Bay Area Governments (ABAG)
- California Geological Survey (CGS)
- California Office of Emergency Services (OES)
- California Seismic Safety Commission
- Center for Earthquake Research & Information (CERI)
- Central United States Earthquake Consortium (CUSEC)
- Consortium of Universities for Research in Earthquake Engineering (CUREE)
- COSMOS Virtual Data Center
- CREW - Cascadia Region Earthquake Workgroup
- Earthquake Engineering Research Institute (EERI)
- Earthquake Information for 2009, USGS
- Earthquake Information for 2010, USGS
- Earthquake Monitoring
- Earthquakes - Online University
- Earthquakes by Bruce A. Bolt Online Companion
- Earthquakes Cause over 1700 Deaths in 2009, USGS
- Earth Science Education Activities
- European-Mediterranean Seismological Centre
- FEMA - Federal Emergency Management Agency
- Finite-source Rupture Model Database
- Global Earthquake Explorer
- GSA - Geological Society of America
- Incorporated Research Institutes for Seismology (IRIS)
- International Association of Seismology and Physics of the Earth's Interior (IASPEI)
- International Seismological Centre (ISC)
- John Lahr's Earthquake website
- McConnell, D., D. Steer, C. Knight, K. Owens, and L. Park. 2010. The Good Earth. 2nd Edition. McGraw-Hill, Dubuque, Iowa.
- Mid-America Earthquake Center
- Multi-Disciplinary Center for Earthquake Engineering Research (MCEER)
- National Geophysical Data Center (NGDC) - NOAA
- National Information Centre of Earthquake Engineering (NICEE)
- National Science Foundation (NSF)
- Natural Hazards Center
- Northern California Earthquake Data Center
- Observatories and Research Facilities for EUropean Seismology (ORFEUS)
- Plummer, C., D. Carlson, and L. Hammersle. 2010. Physical Geology. 13th Edition. McGraw-Hill, Dubuque, Iowa.
- Project IDA
- Quake-Catcher Network
- Saint Louis University Earthquake Center
- Seattle Fault Earthquake Scenario
- Seismographs: Keeping Track of Earthquakes
- Seismological Society of America (SSA)
- Seismo-surfing the Internet for Earthquake Data
- Smithsonian Global Volcanism Program
- SOPAC (Scripps Orbit and Permanent Array Center)
- Southern California Earthquake Center (SCEC)
- Tarbuck, E.J., F.K. Lutgens, and D. Tasa. 2009. Earth Science. 12th Edition. Prentice Hall, Upper Saddle River, New Jersey.
- Tectonics Observatory
- Tracing earthquakes: seismology in the classroom
- UPSeis Seismology Questions Answered
- USGS Earthquake Hazards Program, U.S. Geological Survey
- Western States Seismic Policy Council (WSSPC)
- World Data Center System
- World Organization of Volcano Observatories
- World Seismic Safety Initiative (WSSI)
| 4.324889 |
Jamaican sprinter Usain Bolt's record-setting performances have unleashed a wave of interest in the ultimate limits to human running speed. A new study published in the Journal of Applied Physiology offers intriguing insights into the biology and perhaps even the future of human running speed.
The newly published evidence identifies the critical variable imposing the biological limit to running speed, and offers an enticing view of how the biological limits might be pushed back beyond the nearly 28 miles per hour speeds achieved by Bolt to speeds of perhaps 35 or even 40 miles per hour.
The new paper, "The biological limits to running speed are imposed from the ground up," was authored by Peter Weyand of Southern Methodist University; Rosalind Sandell and Danille Prime, both formerly of Rice University; and Matthew Bundle of the University of Wyoming.
"The prevailing view that speed is limited by the force with which the limbs can strike the running surface is an eminently reasonable one," said Weyand, associate professor of applied physiology and biomechanics at SMU in Dallas.
"If one considers that elite sprinters can apply peak forces of 800 to 1,000 pounds with a single limb during each sprinting step, it's easy to believe that runners are probably operating at or near the force limits of their muscles and limbs," he said. "However, our new data clearly show that this is not the case. Despite how large the running forces can be, we found that the limbs are capable of applying much greater ground forces than those present during top-speed forward running."
In contrast to a force limit, what the researchers found was that the critical biological limit is imposed by time -– specifically, the very brief periods of time available to apply force to the ground while sprinting. In elite sprinters, foot-ground contact times are less than one-tenth of one second, and peak ground forces occur within less than one-twentieth of one second of the first instant of foot-ground contact.
The researchers took advantage of several experimental tools to arrive at the new conclusions. They used a high-speed treadmill capable of attaining speeds greater than 40 miles per hour and of acquiring precise measurements of the forces applied to the surface with each footfall. They also had subjects' perform at high speeds in different gaits. In addition to completing traditional top-speed forward running tests, subjects hopped on one leg and ran backward to their fastest possible speeds on the treadmill.
The unconventional tests were strategically selected to test the prevailing beliefs about mechanical factors that limit human running speeds –- specifically, the idea that the speed limit is imposed by how forcefully a runner's limbs can strike the ground.
However, the researchers found that the ground forces applied while hopping on one leg at top speed exceeded those applied during top-speed forward running by 30 percent or more, and that the forces generated by the active muscles within the limb were roughly 1.5 to 2 times greater in the one-legged hopping gait.
The time limit conclusion was supported by the agreement of the minimum foot-ground contact times observed during top-speed backward and forward running. Although top backward vs. forward speeds were substantially slower, as expected, the minimum periods of foot-ground contact at top backward and forward speeds were essentially identical.
According to Matthew Bundle, an assistant professor of biomechanics at the University of Wyoming, "The very close agreement in the briefest periods of foot-ground contact at top speed in these two very different gaits points to a biological limit on how quickly the active muscle fibers can generate the forces necessary to get the runner back up off the ground during each step."
The researchers said the new work shows that running speed limits are set by the contractile speed limits of the muscle fibers themselves, with fiber contractile speeds setting the limit on how quickly the runner's limb can apply force to the running surface.
"Our simple projections indicate that muscle contractile speeds that would allow for maximal or near-maximal forces would permit running speeds of 35 to 40 miles per hour and conceivably faster," Bundle said.
Peter Weyand is an associate professor of applied physiology and biomechanics in SMU's Annette Caldwell Simmons School of Education & Human Development.
Matthew Bundle is an assistant professor of biomechanics in the College of Health Sciences at the University of Wyoming.
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
| 3.05565 |
Most of us look forward to spring’s arrival: new blooms, new colors and warmer temperatures allowing more outdoor activity. But for the estimated 20 percent of Americans with seasonal allergies, spring can be a time of itchy, watery eyes, sneezing and other miseries of the season. Commonly called “hay fever,” these reactions are referred to by doctors as “seasonal allergic rhinitis,” where rhinitis means inflammation of the lining of the nose. People can be allergic to all sorts of things, but plant pollens are among the most irritating, and spring is their heyday.
The American Academy of Allergy, Asthma and Immunology, the official group of doctors specializing in allergy, recommends that you see an allergist if you have prolonged or severe symptoms of rhinitis, associated asthma or recurrent sinus infections; if your quality of life is adversely affected; or if the medications you take seem not to be working.
But they also recommend 10 tips for avoiding allergy symptoms:
| 3.089972 |
Samuel D. Evans
West Central Experiment Station
University of Minnesota
now Emeritus Professor at Morris, Minnesota
John F. Moncrief
Department of Soil, Water, and Climate
University of Minnesota
Gyles W. Randall
Southern Experiment Station
University of Minnesota
William E. Lueschen
Department of Agronomy and Plant Genetics
University of Minnesota
formerly Head of the Southwest Experiment Station at Lamberton
Copyright © 2002 Regents of the University of Minnesota. All rights reserved.
Management of crop residues with reduced tillage is the most cost-effective method of controlling sediment losses and reducing farming impacts on water quality. Crop residues can also help reduce wind erosion and can enhance snow entrapment. One of the primary water quality concerns for the Minnesota River and its tributaries is sediment, which contributes increased phosphorus (P) to the system. This increased P stimulates algae growth, which is followed by an increased biological oxygen demand when the algae die and decompose. This can deplete dissolved oxygen levels, resulting in game fish stress or kill.
In addition to affecting sediment loss, tillage influences many interacting physical, chemical, and biological properties of soils that can have major impacts on crop production. These properties include temperature, moisture, aeration, bulk density, structure, nutrient distribution, organic matter levels, and microbial populations. Various crops respond to these changes differently. The range of these changes can be amplified by extremes in tillage reduction associated with some residue management alternatives. Small grain is insensitive to temperature changes but may respond to changes in the seed furrow environment and to differing weed species present.
Small grain is a prominent part of the agriculture in the upper Minnesota River basin. Following is a discussion of residue management tillage system effects on small grain production.
On soils classified highly erodible land (HEL) the general requirement is 30 percent residue cover after planting. On non-HEL soils the steepness and length of the slopes will indicate the potential for significant erosion. A second soil factor that must be considered is internal drainage. Poorly drained soils warm up more slowly than well-drained soils, so may require more tillage. Tile drainage may improve this situation, but in some cases this may not be enough to insure consistent success with little or no tillage. A third factor is soil fertility level. Having a high level of fertility is necessary if reduced tillage systems are to perform well. Low fertility conditions offer too many obstacles and generally limit yields in reduced tillage systems. It is important to effectively control sediment at high soil test P levels. Research has shown that this can be done effectively with crop residues in conjunction with other conservation techniques.
The amount of residue present in a field depends on the crop rotation and the level of production. Corn generates more residue than small grains or soybeans; thus it is easier to maintain higher residue levels with a variety of tillage systems. The durability of the residue is also crop dependent. Soybean residue is classified as "fragile," or in other words is easily destroyed. Corn and small grain residues, on the other hand, are classified as "non-fragile."
Spring wheat and soybeans appear to be a viable crop rotation in a no-till system for Minnesota conditions. Other crops that fit well in a small grain rotation are sunflowers, sugar beets, and field beans. Maintaining a sufficient residue cover may be a problem following these crops. Soybean yields after small grain have generally not been affected by tillage. With more intensive tillage systems, crop sequence becomes less important. In summary, both the crops in the rotation and the sequence of the crops are important in tillage management.
Tillage for small grain production requires the management of residue to allow for effective stand establishment. Planting when surface crop residues are relatively dry and are cut more easily with coulters is advisable. Experience has shown that planting in the direction of stubble orientation reduces the effectiveness of coulters and disk openers. Small grain residue pushed into the seed furrow by coulters "cradles" the seed and often results in stand loss and delayed emergence. This is primarily because of slower absorption of soil water due to poor seed-to-soil contact and allelopathic inhibition. Small grains are not as temperature sensitive as corn, so residue effects are mainly due to in-furrow seed-soil contact or phytotoxicity.
Do not surface-apply urea sources of nitrogen (N) without incorporation unless air temperatures are cool or rain is imminent. Urea left on the surface in proximity to residue has a high potential of volatilization losses. With residue management tillage systems, less N is released from soil organic matter due to less physical disturbance. In addition, soil organic matter may increase under some reduced tillage systems, and this will act as a sink for nitrogen. Anhydrous ammonia has been the most consistent source of N. Drill-applied diammonium phosphate (18-46-0) places N and P below the soil surface and close to the seed. This has been very effective in the western Minnesota River basin with calcareous soils that can tie up P. In addition to being a very efficient method of P fertilizer application, it also minimizes the risk of erosive losses of P.
The effects of tillage on the development and severity of crop diseases are variable, depending on the disease, the specific type of tillage system used, and the effectiveness of the other disease management practices used. Conservation tillage usually reduces soil temperatures, conserves soil moisture, and leaves crop residue on the soil surface. Of particular concern are crop diseases that are favored by cool, wet soils. Diseases most troublesome in high-residue tillage systems are those that have inoculum associated with crop residues left on the soil surface. In many cases the diseases are most noticeable when monoculture cropping is practiced. Diseases of most concern are scab and tan spot, both of which are associated with plant residue. However, in addition to the disease inoculant supplied by residue, the proper environment and susceptible varieties must be present for economic infestations.
Controversy exists over what type of seed openers (disk vs. hoe vs. sweep) deal with small grain residue most effectively. Generally, hoe openers work better in drier soil. Hoe-type openers operate below residue, making "in furrow" residue less probable. Sweep or air seeders, placing seeds below sweeps, also reduce the probability of intimate contact of seed with crop residue. Depth control is the challenge with sweep seeders. Press wheels should also be used for good stand establishment under dry conditions. Disk-type openers require the most caution in this respect, but work better under wet conditions. If considering no-till small grain production, it is essential to use a properly designed, heavy duty drill that can cut through the residue, place seed in contact with the soil without incorporating residue, and firm the soil over the seed. Selecting a drill with fertilizer capability is also important.
Various factors including soil characteristics, crop rotation, residue management, disease problems, seeding equipment, and management ability must be considered when selecting a residue management system including small grains. In rotations with moderate amounts of residue, many systems will work on a variety of soils. With higher residue levels, the importance of proper residue management and heavy duty reduced tillage drills will ensure proper seed-to-soil contact without significant residue in contact with the seed. In the upper Minnesota River basin, higher levels of residue may contribute to increased soil moisture and subsequent yield increases in dry years. Crop rotation is a major factor in minimizing the disease problems in small grains.
The results of studies in Douglas, Norman, and Becker Counties are shown in Table 1 . In these studies tillage plots were split, with winter and spring wheat planted into barley stubble.
On average, spring wheat yields following barley were not affected by tillage. Only in one site year (1986 in Becker County) did tillage significantly affect spring wheat yields. A bindweed problem at this site was the likely cause. At most sites an increase in foxtail (pigeon weed) was associated with chisel and no-till systems.
Results of some recent studies near the headwaters of the Pomme de Terre River in Ottertail County are shown in Table 2. Tillage affected spring wheat yields at only one site year out of five (in 1994). The yield reduction in 1994 was linked in part to stand reduction with the no-till system. The drill used had a single disk opener. At the other site years spring wheat yields following soybeans were not affected by tillage.
The Paraplow is a unique type of subsoiler which leaves surface residue minimally disturbed. Even though soils were very dense in the fall of 1993, subsoiling that fall reduced spring wheat yields the next year. Paraplowing reduced stand compared to a chisel plowing system. On average there was a 4 bu/acre yield reduction with the no-till system compared to the chisel plow-based system.
In a continuous wheat study on a Barnes loam near Morris ( Table 3 ) there were no significant effects of tillage on yield in the three years measured. Sometimes protein content can be used as an indicator of reduced N availability. For this reason it is presented in Table 2 and Table 3 . Protein contents appeared to be more affected by environment than by tillage system. Protein differences between tillage systems were very small.
Traditionally there has been very little winter wheat grown in Minnesota. This is primarily due to the harshness of the winters. In some years lower prices (vs. spring wheat) and the lack of a suitable crop sequence may also be a factor. In most years, with a clean-tillage system there will be substantial winter kill. This limits varietal selection to only the most winter hardy. In some instances this is at the expense of intrinsic yield potential, protein content, and disease resistance.
The studies in Table 1 illustrate the potential for winter wheat production when stubble is managed for snow catch in an effort to insulate the soil. North Dakota research has shown that if 4 inches of snow are caught by stubble, winter wheat is protected to -30° F. In the three-year study at three locations, winter wheat yields were slightly higher than spring wheat and there was little effect of tillage. Disease management is more important with winter wheat, however.
Data from six trials in northwestern Minnesota where barley was grown after soybeans with spring-applied urea showed no difference in yield or protein due to tillage ( Table 4 ).
Success of reduced tillage approaches to small grain production have been higher when preceded by a low residue crop such as soybeans. Spring wheat and barley following soybeans have generally not been affected with most alternative tillage approaches. A no-till system resulted in more variability in yields (higher or lower than a moldboard plowing system). No-tillage sometimes posed challenges in stand establishment, N management, and weed control.
By catching snow with barley stubble, no-tillage systems allow winter wheat to be grown in Minnesota with less "overwintering" risk. Winter and spring wheat resulted in comparable yields, although performance was more variable for winter wheat. This provides an opportunity for growers to reduce their labor during peak labor demand periods (spring and fall). It also allows for more flexibility to accommodate variations in weather.
Tillage passes with different implements can be used very effectively to create various levels of residue remaining on the soil surface. Four tillage systems shown below are categorized in the following Tables 5-8 according to the residue management/yield performance indicators also shown below:
Moldboard Plow: Fall moldboard plowing followed by one or two secondary spring tillage operations before seeding.
Chisel Plow: Fall chisel plowing plus secondary spring tillage before seeding. Special attention should be paid to use of proper shaped/width shovels and implement speed in order to maintain proper residue cover.
Spring Disk/Field Cultivator: One or two passes in the spring prior to seeding.
No-till: All seedbed preparation is performed by the drill.
Inadequate Residue to Minimize Erosion
(less than 30 percent of soil surface covered after planting).
Where erosion is not a concern, fall moldboard plowing may be the best practice.
Recommended with Good Management.
No yield penalty is expected if the farmer observes all relevant recommended management practices for high-residue systems.
Excellent Management Required.
Slight yield penalty is possible, even if all recommended management practices are observed. Above average crop management will be needed to ensure good performance.
Reduced Yield Potential.
The potential exists for substantially reduced yields, especially on poorly drained soils in wet years.
A number of tables have been developed which estimate residue management/yield performance of various crop rotations involving corn, soybeans, and/or small grains. Continuous corn and corn-soybean sequences are discussed in other publications. In those publications the Minnesota River basin was divided into high annual rainfall (>28 inches) and low rainfall (<28 inches) areas. This north-south line is approximately halfway between Highways 71 and 15. Since most small grain is grown in the low rainfall segment of the Minnesota River basin, indices were developed only for that section of the basin. In each crop sequence, separate indices were developed for glacial till (deposited in place by melting glacier, poorly sorted) and lacustrine (deposited in glacial lakes, well-sorted) soils.
Moldboard Plow: This systems generally results in high yields but leaves inadequate surface residue to minimize soil erosion. For this reason it should not be used except on level soils where erosion is not a concern, to alleviate surface soil compaction, to incorporate P and K fertilizer, or to incorporate manure.
Chisel Plow: This tillage system generally results in high yields but care must be taken to insure adequate surface residue cover. In most cases straight chisel shanks should be used to achieve 30 percent residue cover. For small grain following soybeans this system will result in less than 30 percent cover, so it is not recommended.
Spring Disk/Field Cultivator: On glacial till soils this tillage system will result in good yields and will leave adequate residue if the implement is properly set. On lacustrine soils this system will probably result in some yield loss due to delayed planing for small grain following soybean. It will also require a high level of management on other crop sequences with higher residue production.
No-till: On glacial till soils this system will work well for small grain following soybeans or soybeans following small grains. For corn following small grain or small grain following small grain, some yield loss would probably result. On the lacustrine soils the no-till system will likely result in yield loss (even with good management) for small grain following soybean or soybean following small grain due to delayed planting. For the other crop sequences substantial yield loss would occur.
To order other publications in this series, contact your Minnesota County Extension Office, or outside of Minnesota, contact the Extension Store at (612) 625-8173. Titles in this series include:
This set of publications was the result of a joint effort between Minnesota Extension Service, Minnesota Agricultural Experiment Station, and Minnesota Pollution Control Agency. This information was first presented February of 1995 at the Sediment Control Solutions Conferences in Mankato and Montevideo, Minnesota.
In accordance with the Americans with Disabilities Act, this material is available in alternative formats upon request. Please contact your University of Minnesota Extension office or the Extension Store at (800) 876-8636.
| 3.404837 |
Introductionfox, carnivorous mammal of the dog family, found throughout most of the Northern Hemisphere. It has a pointed face, short legs, long, thick fur, and a tail about one half to two thirds as long as the head and body, depending on the species. Solitary most of the year, foxes do not live in dens except in the breeding season; they sleep concealed in grasses or thickets, their tails curled around them for warmth. During the breeding season a fox pair establishes a den, often in a ground burrow made by another animal, in which the young are raised; the male hunts for the family. The young are on their own after about five months; the adults probably find new mates each season.
Foxes feed on insects, earthworms, small birds and mammals, eggs, carrion, and vegetable matter, especially fruits. Unlike other members of the dog family, which run down their prey, foxes usually hunt by stalking and pouncing. They are known for their raids on poultry but are nonetheless very beneficial to farmers as destroyers of rodents.
Foxes are occasionally preyed upon by larger carnivores, such as wolves and bobcats, as well as by humans and their dogs; birds of prey may capture the young. Despite extensive killing of foxes, most species continue to flourish. In Europe this is due in part to the regulatory laws passed for the benefit of hunters. Mounted foxhunting, with dogs, became popular in the 14th cent. and was later introduced into the Americas; special hunting dogs, called foxhounds, have been bred for this sport. Great Britain banned foxhunting in which the hounds kill the fox in 2005.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.
See more Encyclopedia articles on: Vertebrate Zoology
| 3.492513 |
Sulaimaniyah (sōˌlāmänˈēə) [key], town (1987 pop. 364,096), NE Iraq. The town, founded in 1789, is a trade center inhabited by Kurds and has long been a center of Kurdish nationalism. Since 1992 it has been an important town in the so-called Kurdish Autonomous Region.
More on Sulaimaniyah from Fact Monster:
See more Encyclopedia articles on: Iraq Political Geography
| 3.214049 |
Zugspitze (tsōkˈshpĭtˈsə) [key], mountain, 9,721 ft (2,963 m) high, in the Bavarian Alps and on the German–Austrian border; highest peak of Germany. A cog-and-pinion railroad connects the popular resort of Garmisch-Partenkirchen, at its foot, with the summit. Zugspitze is home to a meteorlogical observatory.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.
More on Zugspitze from Fact Monster:
- Germany - Information on Germany — geography, history, politics, government, economy, population statistics, culture, religion, languages, largest cities, as well as a map and the national flag.
- Garmisch-Partenkirchen - Garmisch-Partenkirchen Garmisch-Partenkirchen , town (1994 pop. 27,000), Bavaria, S Germany, in the ...
- Bavaria: Land - Land A region of rich, softly rolling hills, it is drained by several rivers (notably the Main, ...
- Germany: Land and People - Land and People Germany as a whole can be divided into three major geographic regions: the ...
- Encyclopedia: Central European Physical Geography - Encyclopeadia articles concerning Central European Physical Geography.
| 3.03076 |
Stream Quality Assessment Program
A stream is a combination of all of its physical, chemical and biological characteristics. Human activities shape and alter many of these characteristics. The health of our rivers and streams is closely linked to their surrounding watersheds. Ecologists measure the extent to which human activities affect watershed health by gathering and recording information on physical conditions, water quality and living communities in streams and in the surrounding environment. The long-term stream monitoring program meets the requirements of state and federal regulations and supports the Board of Supervisors' environmental improvement program by providing an ongoing evaluation of the streams. The program maintains a substantial database, which over time will be used to determine the overall rate of change or trends in the conditions of our waterways.
Based on biological data collected at 39 randomly selected locations (see map of monitoring site locations) throughout Fairfax County in 2012, approximately 75.0 percent of Fairfax County's streams are in fair to very poor condition. This indicates that many of our streams are significantly impaired and lack biological diversity.
The Stream Quality Index (SQI) is based on annual data collected on resident populations of benthic macroinvertebrates (animals without a backbone that live on the bottom of a stream, river, lake and are visible to the naked eye). As benthic macroinvertebrates are good indicators of water quality, the SQI is used to evaluate long-term trends in the overall health of streams. Each of the 39 randomly selected locations is placed in one of five rating categories (excellent, good, fair, poor or very poor) based on the diversity of benthic macroinvertebrates found in that stream segment. An index value ranging from one to five, with a higher number indicating better stream quality, is calculated for the year based on the percent of sampling locations that fall into each rating category. Results from 2004 through 2012 can be found in the table below. The 2012 SQI shows a decrease in overall stream quality from 2011. Over the past nine years of sampling, a very small increase in the overall index has emerged. As more data are reported annually, trends can be identified with greater certainty.
|Sampling Year||Percent Very Poor||Percent Poor||Percent Fair||Percent Good||Percent Excellent||Stream Quality Index|
Stream and watershed health are evaluated using a variety of indicators such as water quality parameters, bacteria levels, resident invertebrate and fish communities and habitat conditions. The results of the yearly monitoring events are compiled into annual reports and are used to support other environmental initiatives. Additional information on monitoring methods can be found by selecting one of the pictures below.
For more information on the Stream Quality Assessment Program, please email the Stormwater Planning Division or call 703-324-5500, TTY 711.
| 3.658747 |
of Scotland's "traditional" Christmas celebrations (other
than the religious festival) originated in the 19th century (Prince
Albert, Queen Victoria's husband, had a lot to do with it!) and
so England and Scotland developed the same traditions from around
that time, Christmas trees, decorations, Santa Claus, presents,
stockings at the end of the bed, Christmas Carols, Christmas cards
etc. Christmas cards are said to have been invented in Great Britain
in the mid-nineteenth century.
or Yuletide, has never been celebrated in Scotland to the same
extent as Hogmanay. As might be expected there is a Yule Bannock,
which was divided into farls or quarters by the sign of the cross.
The bannocks were baked before dawn on the morning of Christmas
Day, and one given to each member of the family. If it could be
kept intact until the evening meal this augered good fortune for
the coming year. If broken, or nibbled, good fortune would be
broken too. However, this round bannock, like so many others,
has an earlier origin linked to the sun.
To Scottish Cooking
| 3.129076 |
GAINESVILLE, Fla. — Joint research between Florida Museum of Natural History and Chinese scientists to discover and interpret the world’s earliest known flowering fossil is the subject of a PBS NOVA documentary, “First Flower,” which debuts at 8 p.m. April 17.
The origin of flowers is one of botany’s deepest mysteries, and in the NOVA documentary, Florida Musuem paleobotanist David Dilcher guides viewers through segments of the amazing story of the evolution of flowers.
“There’s no doubt about it, flowers are all about sex,” said Dilcher, a graduate research professor and paleobotany curator at the Florida Museum and a member of the National Academy of Sciences.
The search for the world’s first flower drew Dilcher to a remote Chinese lake where colleague Sun Ge of Jilin University in Changchun, China, discovered a 125 million-year-old fossil that scientists believe is the earliest known flower.
Although the fossil lacked the aesthetic petals associated with modern flowers, Dilcher recognized the plant stalk had seeds enclosed within carpels, which are female reproductive structures found in flowers. This led him to conclude the fossil was in fact an early form of a flower. The fossil was named Archaefructus liaoningensis, which means “ancient fruit from Liaoning Province of northeast China.”
Flower production demands an amazing amount of a plant’s precious energy, which leads some scientists to question why and how the world’s first flowers evolved. Angiosperms, or flowering plants that have male pollen and female ovaries, are thought to have made their first appearance on earth roughly 130 million years ago. Today, they dominate the plant world. Today, bees, moths, hummingbirds and other insects facilitate plant reproduction by spreading pollen, but this is the culmination of a complex relationship that evolved over millions of years and that scientists are still decoding.
“Flowering plants were the first advertisers in the world,” Dilcher said. “They put out beautiful colors, colorful patterns, they put out fragrances. And they gave a reward such as nectar or pollen for any insect that would come and visit them.”
Flowers go to elaborate lengths to advertise their sexual organs, the female parts and the male parts, Dilcher said.
“If they could attract these mobile pollinators to visit, crawl around, and feed in flowers, pick up pollen on their legs, pick up pollen on their bodies,” Dilcher said, “and then fly to another flower some distance away, and repeat this process, they could effectively transfer their male genetic material some distance away to another flower.”
Pamela and Doug Soltis, Florida Museum researchers who study plant and flower DNA to better understand evolutionary origins, also are interviewed in “First Flower.” The Soltis’ work addresses evolutionary origins of flowers and flowering plants, plant speciation and the conservation genetics of endangered plant species in Florida. Doug Soltis also is chair of UF’s Department of Botany.
The journal Science featured Sun’s and Dilcher’s fossil flower research on its cover in 1998 and 2002. Sun is a geologist and director of the paleontology and stratigraphy lab at Jilin University. Dilcher holds professorial appointments and teaches at Jilin University and Nanjing University in China, in addition to teaching at the University of Florida.
Writer: DeLene Beeland
Media contact: Paul Ramey, [email protected]
Source: David Dilcher (352) 392-1721 ext. 460
Source: Sun Ge (352) 392-1721 ext. 460; until April 12
| 3.711769 |
An independent Republic of Armenia was proclaimed at the end of the 1914-1918 War but it lasted only until the beginning of the 1920s when the Bolsheviks incorporated it into the Soviet Union. Armenia's return to independence in 1991 was overshadowed by the conflict over Nagorno-Karabakh, the predominantly Armenian-populated region in Azerbaijan (see Current conflicts section). Full-scale war broke out the same year as ethnic Armenians in Karabakh fought for independence, supported by troops and resources from Armenia proper. A ceasefire in place since 1994 has failed to deliver any lasting solution.
Russia, France and the US co-chair the OSCE's Minsk Group, which has been attempting to broker an end to the dispute for over a decade. In 1997, the group tabled settlement proposals seen as a starting point for negotiations by Azerbaijan and Armenia but not by the de facto authorities in Nagorno-Karabakh itself. When the then-Armenian-president Levon Ter-Petrosyan tried to encourage Nagorno-Karabakh to enter into talks he was forced to resign amid cries of betrayal. Azerbaiijan declared illegitimate a referendum held in the region in December 2006.
Armenia's president Serzh Sarkisian and Azerbaijan's Ilham Aliyev agreed in November 2008 to intensify their efforts to find a political settlement to the dispute over Nagorno-Karabakh. They claimed to have made significant progress at talks in Prague in May 2009 on the sidelines of the EU's Eastern Partnership summit. This overview is based on the BBC online country profile for Armenia.
| 3.51767 |
The Jordan River, which cuts through Israel and Jordan, largely reflects the scarcity of water in the region. The above picture shows a rare flooding event in the Jordan River in the winter of 2003 at the Baptist site (well-known in Christianity). Just several months later, during the summer of 2003, the river was dry again, as shown below at a site close to Abdalla Bridge. Courtesy of Avner Vengosh.
Data collected from more than 6,000 selected sampling points reveal that more than 10 percent of the water resources in the Mediterranean basin have boron levels exceeding 1 milligram per liter, the new E.U. drinking water standard. We found that the highest values of boron are in areas associated with geothermal activity, such as in Tuscany, Italy, and Chalkidiki, Greece. In addition, we discovered high boron levels in the groundwater basins in the central part of Cyprus and in the southern coastal aquifer that is shared between Israel and the Gaza Strip. In order to delineate the origin of boron and salinity in these groundwater basins, we investigated the chemical and isotopic compositions of the boron-contaminated groundwater.
Boron has two stable isotopes that are distributed unevenly among different geological materials and natural water resources. Because different sources of water pollution have unique isotopic fingerprints, we were able to use the boron isotopes to identify clearly the source of the water contamination. For example, the boron isotopic ratios in seawater, wastewater and rocks vary significantly. Thus, when groundwater is contaminated, the imprinted isotopic signature of these different sources is preserved, serving as a tracer for delineating their origin. Similarly, the application of other isotopes such as oxygen, hydrogen and strontium provide a clue to the origin of the polluted water. By integrating these chemical tools, we discovered that the boron contamination in the Mediterranean groundwater basins is derived primarily from natural processes.
In the Cornia basin in Tuscany, we found that boron leaching from sediments into local groundwater is associated with seawater intrusion, reflecting a complex history of boron uptake and release by clay minerals. In western Chalkidiki, the mixing of groundwater with underlying thermal water rich in boron caused the boron contamination. In Cyprus, water-rock interaction is the main mechanism for the boron enrichment in the water. In the southern coastal aquifer of Israel and the Gaza Strip, we discovered that boron pollution is associated with the migration of saline groundwater from Israel into the Gaza Strip.
The chemical and isotopic compositions of the groundwater in these studies clearly indicate that the boron problem in the Mediterranean water resources, on the whole, is derived from natural (geogenic) sources rather than anthropogenic ones.
Our results have several implications for the management of national and transboundary groundwater resources in the Mediterranean basin and for the remediation of boron.
Perhaps most importantly, we are challenging the conventional perception that the boron contamination in these countries is a source of human pollution. For years, companies added boron to detergents because it is an excellent bleaching agent thus resulting in the formation of boron-rich sewage. Moreover, similar to other inorganic ions, boron is not removed during standard sewage treatment processes and even treated wastewater typically has high boron concentrations.
Thus, as a precautionary measure, environmental regulators in both Cyprus and Israel have chosen a particular strategy to reduce boron contamination: mandating regulations that restrict the amount of boron that can be added to detergents. Although the reduction in boron in treated sewage may prove to be beneficial for agriculture because there will be less boron contamination in the irrigation water, these regulations will have negligible effects for improving drinking water.
For a country that soon will join the European Union, such as Cyprus, it will only be able meet its obligation to abide by E.U. standards for drinking water by pursuing an alternative strategy that calls for technological intervention to remove boron. To date, Israel has yet to adopt an official drinking water standard for boron, despite the new proposals for desalination calling for 0.5 milligrams per liter boron in desalinated water. Thus, Israel already faces a similar challenge to Cyprus.
In short, because boron contamination in all our investigated cases comes from natural geochemical background pollution and hence cannot be prevented, the only way to address the boron problem is through treatment of the drinking water.
At present in Italy and Israel, water authorities mix the boron-rich water with high-quality water to reduce the level of boron in the water supplied for both drinking and agricultural purposes. However, the longevity of dilution as a solution is limited, primarily due to the diminishing amount of high-quality water that is available. As a result, our research has focused on the creation of alternative water resources, through the application of technological solutions such as improved desalination and the introduction of new techniques for boron removal from the water.
Reverse osmosis desalination has tremendous potential for a supply of new water for the 21st century, especially in areas of the world where water is scarce or the quality is inadequate. Its widespread application, however, is hampered by the fact that reverse osmosis desalination does not remove boron sufficiently (only 60 percent). As a result, desalination of seawater does not reduce the boron level below the new standard for drinking water in the European Union (and will be also problematic for the non-European Mediterranean countries adopting a similar drinking water standard for boron). Therefore, additional removal techniques must be introduced in order to bring boron levels down to drinking standards.
Different partners in the BOREMED project have developed several independent methodologies for removing boron from water. In Cyprus, BOREMED partners have utilized boron-specific resins combined with a small-scale reverse osmosis to reduce the amount of boron in the groundwater for local users. In Israel, BOREMED partners have succeeded in removing boron by optimization of reverse osmosis processes such as multi-step desalination. Other partners from the Netherlands have established a new method of boron removal through co-precipitation with hydroxides. In addition, a joint Israeli-Turkish team invented a new technique for boron removal through reacting seawater with fly ash and coal materials. This method is particularly useful in Mediterranean countries such as Turkey, where fly ash is abundant and cheap.
Each of the new different methodologies has its own benefits and costs. Ultimately, the E.U. countries that face a boron problem will have to adopt one of these new technologies in order to be in compliance with the new drinking water standard for boron.
Through an integration of geochemistry, hydrogeology, numerical modeling and policy analysis, we also have devised a potential management solution to the water crisis in the Gaza Strip. The local aquifer underlying the Gaza Strip is perhaps one of the most stressed resources in the Mediterranean basin in terms of water quantity and quality: Chloride concentrations reach 1,500 milligrams per liter (six times the E.U. standard); nitrate concentrations reach 400 milligrams per liter (eight times the E.U. standard); and boron concentrations reach 3.5 milligrams per liter (more than three times the E.U. standard).
Over the past five decades, the amount of water pumped from the Gaza aquifer has far exceeded the natural water replenishment. As the water level has declined, the water quality has become unsuitable for human consumption, owing to the high levels of salinity, boron and nitrate pollution. Nevertheless, more than 1 million people depend entirely upon this aquifer for drinking and irrigation water.
The BOREMED project has mapped boron distribution in groundwater from the southern Mediterranean coastal aquifer and the Gaza Strip. The different colors represent boron concentration in milligrams per liter. In most parts of the aquifer and the Gaza Strip, the boron concentration exceeds the drinking standard of 1 milligram per liter for the European Union. Courtesy of Avner Vengosh.
Our chemical and isotopic data show that most of the salinity phenomenon in the Gaza Strip is derived from flow of natural saline groundwater from Israel towards the Gaza Strip. As a result, the southern coastal aquifer does not resemble a classic upstream-downstream dispute over a transboundary aquifer: Israels upstream pumping of the saline groundwater can potentially reduce the salinization rates of groundwater in the Gaza Strip rather than cause downstream harm.
Numerical simulation of different pumping scenarios confirms our hypothesis that increasing pumping along the Gaza Strip border combined with desalination and supply to the Gaza Strip, as well as moderate reduction of pumping within the Gaza Strip, would improve the water quality of groundwater there. Moreover, our finding that the salinity problem in the Gaza Strip is partially natural de-politicizes the water issue and offers a practical solution for the water crisis in the Gaza Strip that has win-win benefits for both the Palestinian Territory and Israel.
Clearing the way
The promulgation of a new drinking water standard for boron in the European Union has forced both E.U. member and non-member states to address boron contamination in drinking water even before a strong causal link has been found between boron contamination and health effects. Yet, while new technologies now exist for boron removal, the adoption of this new drinking water standard is complicated by the fact that each country faces different institutional constraints.
In Italy, the boron problem is a local problem rather than a national one, and as a result, the end-user in conjunction with the regional water authority is responsible for developing its own program for boron removal. In contrast, in the coastal aquifer that is shared between Israel and the Palestinian Authority, the boron and salinity problem will only be resolved through the development of institutions for international cooperation. Finally, in Cyprus, the boron problem is a national problem, thus requiring a national solution instead of a local or international solution.
In the end, the ability to address the boron problem at the local, national and international levels in the Mediterranean basin will depend entirely on an integration of science, technology and policy.
At the surface,
northern Africa is one of the driest places on the planet. But underneath
the desert, ancient water lies in a complex groundwater system composed
of the Nubian aquifer. Radiocarbon dating techniques have indicated that
most Nubian aquifer water is at least 50,000 years old, but a newly developed
technique shows that some of the water is 1 million years old adding
further complexity to the Nubian aquifer system, which waters the region.
Boron is only one of many geologic materials that occur naturally in the environment
and can pose health risks to people. Geoscientists are actively involved in
studying such substances by monitoring groundwater, surface water and soils,
and by mapping their distributions. The findings may help policy-makers devise
new strategies for regulation and mitigation. Online sources for asbestos, radon,
mercury, arsenic, crystalline silica and boron are listed below; also see link
to past Geotimes coverage. See this month's print issue for more
| 3.765545 |
Map: Do You Live in a Food Desert? USDA's Food Desert Locator Map
Yesterday, the United States Department of Agriculture unveiled its latest online tool: an eye-opening map of the nation's "food deserts."
These food deserts (marked in pink above) are places where there is "low income" and "low access"—or places where at least a fifth of the population lives at or below the poverty line and where there isn't a supermarket within a one-mile radius (or within a 10-mile radius in rural areas). All things told, about 13.5 million people nationwide have little or no access to stores selling healthful food.
The complete dataset is downloadable, so it should spawn mash-ups. The USDA has also created the Food Environment Atlas, which maps factors ranging from food taxes to farmers' markets (below). What correlations can we make about the absence of food deserts and farmers' markets?
The data's impressive and certainly opens up opportunities to map other connections: What's the impact of healthy corner stores, walkable school districts, or even McDonald's locations on food deserts? Could we put the "Wal-Mart as food desert solution" theory to the test?
Map: USDA (via Alex Howard).
| 3.186284 |
Counting, recognizing numbers 1 to 5, alphabet and prewriting practice, and more.
Visualizing addition, counting to 10, learning the alphabet, indentifying shapes, and more.
Building addition and subtraction skills, telling time, recognizing letters, and more.
Money math, adding multiple digits, learning contractions, recognizing parts of speech, and more.
Finding area, division drills, learning about fractions, alphabetizing, is it I or me, and more.
Triangle types, math with fractions and mixed numbers, writing equations, word problems, finding antonyms, and more.
Decimal subtraction, improper fractions, cause and effect, commas, and more.
Quick, hands-on projects to captivate your little one.
Learning activities to try in the kitchen, at snack time, and more.
From mummies to family trees, find cool art projects to entertain and teach your child.
Find silly word games and other activities to build crucial academic skills - all while having fun.
Get ideas for cool new books your little publisher can make.
See how everyday chores can be transformed into fun learning activities.
Help your child rediscover the majesty of old-fashioned concepts like snail mail, journals, and family trees.
| 3.442133 |
In 2006, high sea temperatures caused severe coral bleaching in the Keppell Islands, in the southern part of the reef — the largest coral reef system in the world. The damaged reefs were then covered by a single species of seaweed which threatened to suffocate the coral and cause further loss.
A "lucky combination" of rare circumstances has meant the reef has been able to make a recovery. Abundant corals have reestablished themselves in a single year, say the researchers from the University of Queensland's Centre for Marine Studies and the ARC Centre of Excellence for Coral Reef Studies (CoECRS).
"Three factors were critical," said Dr Guillermo Diaz-Pulido. "The first was exceptionally high regrowth of fragments of surviving coral tissue. The second was an unusual seasonal dieback in the seaweeds, and the third was the presence of a highly competitive coral species, which was able to outgrow the seaweed."
Coral bleaching occurs in higher sea temperatures when the coral lose the symbiotic algae they need to survive. The reefs then lose their colour and become more susceptible to death from starvation or disease.
The findings are important as it is extremely rare to see reports of reefs that bounce back from mass coral bleaching or other human impacts in less than a decade or two, the scientists said. The study is published in the online journal PLoS one.
"The exceptional aspect was that corals recovered by rapidly regrowing from surviving tissue," said Dr Sophie Dove, also from CoECRS and The University of Queensland.
"Recovery of corals is usually thought to depend on sexual reproduction and the settlement and growth of new corals arriving from other reefs. This study demonstrates that for fast-growing coral species asexual reproduction is a vital component of reef resilience."
Last year, a major global study found that coral reefs did have the ability to recover after major bleaching events, such as the one caused by the El Niño in 1998.
David Obura, the chairman of the International Union for Conservation of Nature climate change and coral reefs working group involved with the report, said: "Ten years after the world's biggest coral bleaching event, we know that reefs can recover – given the chance. Unfortunately, impacts on the scale of 1998 will reoccur in the near future, and there's no time to lose if we want to give reefs and people a chance to suffer as little as possible."
Coral reefs are crucial to the livelihoods of millions of coastal dwellers around the world and contain a huge range of biodiversity. The UN's Millennium Ecosystem Assessment says reefs are worth about $30bn annually to the global economy through tourism, fisheries and coastal protection.
But the ecosystems are under threat worldwide from overfishing, coastal development and runoff from the land, and in some areas, tourism impacts. Natural disasters such as the earthquake that triggered the Indian Ocean tsunami in 2004 have also caused reef loss.
Climate change poses the biggest threat to reefs however, as emissions of carbon dioxide make seawater increasingly acidic.
Last year a study showed that one-fifth of the world's coral reefs have died or been destroyed and the remainder are increasingly vulnerable to the effects of climate change.
The Global Coral Reef Monitoring Network says many surviving reefs could be lost over the coming decades as CO2 emissions continue to increase.
| 4.02417 |
Teens Using Technology - Backlit Devices can Impact on Sleep
New research from the Lighting Research Center (LRC) at Rensselaer Polytechnic Institute, New York, indicates that teenagers who use backlit technology, such as tablet devices, for two hours before bed, may have their sleeping patterns disrupted. At this time of year in Australia, many teens are studying for their final HSC exams and using computers for extended periods. Being aware of backlit technology's possible effects on sleep and melatonin release, may help parents advise their teens on how to ensure they get sufficient sleep.
We know that sleep has an impact on learning and information retention so we've written about this topic before. For more information on sleep and teens, please read:
Backlit Devices May Interrupt Sleeping Patterns
The new LRC research shows that a two-hour exposure to electronic devices with self-luminous 'backlit' displays causes melatonin suppression, which might lead to delayed bedtimes, especially in teens. “Our study shows that a two-hour exposure to light from self-luminous electronic displays can suppress melatonin by about 22%. Stimulating the human circadian system to this level may affect sleep in those using the devices prior to bedtime,” said Professor Figueiro. And until manufacturers develop more “circadian-friendly” electronic devices that increase or decrease light exposure based on time of day, Figueiro recommends "dimming these devices at night as much as possible in order to minimize melatonin suppression, and limiting the amount of time spent using these devices prior to bedtime.”
Your teens might not want to hear this information during other times of the year when they want to play games on tablet-style devices but perhaps during final exam times, they'll be more receptive to this information.
Morning Light Helps Teens Sleep
Another field study by the LRC in 2010 indicated that teenagers are likley to have better sleep if they have more exposure to morning light. During term time, high schools have schedules requiring teenagers to be in school early in the morning, so teens often miss some morning light. However, during a study break, your teen has an opportunity to change this pattern and possibly benefit from more and better sleep. “As teenagers spend more time indoors, they miss out on essential morning light needed to stimulate the body’s 24-hour biological system, which regulates the sleep/wake cycle,” said Professor Figueiro. In this study it was found that students who wore special glasses to prevent short-wavelength (blue) morning light from reaching their eyes experienced a 30-minute delay in sleep onset by the end of five days.
Good luck getting your teens out of bed for some morning exercise and all the best to everyone supporting teenagers studying for their final HSC exams.
| 3.52013 |
| Recommended Intake
| Calcium Deficiency
| Calcium Toxicity
| Major Food Sources
| Health Implications
| Tips for Increasing Your Calcium Intake
| Taking Supplements
Calcium is the most prevalent mineral in the human body. About 99% of the body's calcium resides in the bones and teeth, and the remaining 1% is dispersed throughout other body fluids and cells.
Calcium's functions include:
- Builds bones, both in length and strength
- Helps bones remain strong by slowing the rate of bone loss with age
- Helps muscles contract
- Helps the heart beat
- Plays a role in normal nerve function, transfers nerve impulses
- Helps blood clot during bleeding
- Builds healthy teeth (in kids)
The Institute of Medicine offers these recommendations:
Recommended Dietary Allowance or •Adequate Intake (mg/day)
|Birth to 6 months||200 milligrams (mg)||200 mg|
|7-12 months||260 mg||260 mg|
|1-3 years||700 mg||700 mg|
|4-8 years||1,000 mg||1,000 mg|
|9-18 years||1,300 mg||1,300 mg|
|19-50 years||1,000 mg||1,000 mg|
|51-70 years||1,200 mg||1, 000 mg|
|71 years and older||1,200 mg||1,200 mg|
|Pregnant or lactating teens||1,300 mg||n/a|
|Pregnant or lactating adults||1,000 mg||n/a|
In childhood, not getting enough calcium may interfere with growth. A severe deficiency may keep children from reaching their potential adult height. Even a mild deficiency over a lifetime can affect bone density and bone loss, which increases the risk for osteoporosis.
If you do not consume enough calcium, your body will draw from the storage in your bones in order to supply enough calcium for its other functions: nerve transmission, muscle contraction, heartbeat, and blood clotting.
Symptoms of a calcium deficiency include:
- Intermittent muscle contractions
- Muscle pain
- Muscle spasms
- Numbness or tingling in the hands and feet
Very large doses over a prolonged period of time may cause kidney stones and poor kidney function. Your body may not absorb other minerals, such as
zinc, properly. These problems could occur from consuming too much through a calcium supplement, not from milk or other calcium-rich foods. The tolerable upper intake level (UL) depends on age.
Upper Level Intake (mg/day)
|Birth to 6 months||1,000 milligrams (mg)||1,000 mg|
|7-12 months||1,500 mg||1,500 mg|
|1-8 years||2,500 mg||2,500 mg|
|9-18 years||3,000 mg||3,000 mg|
|19-50 years||2,500 mg||2,500 mg|
|51 years and older||2,000 mg||2,000 mg|
|Pregnant or lactating teens||3,000 mg||n/a|
|Pregnant or lactating adults||2,500 mg||n/a|
Major Food Sources
Dairy foods—milk, yogurt, and some cheeses—are the best dietary sources of calcium. These foods are also rich in vitamin D, which helps the body absorb calcium.
|Macaroni and cheese, homemade||1 cup||362|
|Parmesan cheese||1 Tbsp||336|
|Eggnog, nonalcoholic||1 cup||330|
|Chocolate milk||1 cup||300|
|Ricotta cheese||½ cup||300|
|Powdered milk||¼ cup||290|
|Cheddar cheese||1 ounce||250|
|Swiss cheese||1 ounce||250|
|Provolone cheese||1 ounce||215|
|Cheese pizza||1/6 frozen pizza||210|
|Mozzarella cheese||1 ounce||175|
|American cheese||1 ounce||160|
|Cottage cheese||1 cup||120|
|Frozen yogurt, soft serve||½ cup||100|
|Ice cream||½ cup||80|
Absorption of calcium from some other dietary sources is not as great as that from dairy foods. Specifically, dark green vegetables contain oxalates, and grains contain phytates, which can bind with calcium and decrease their absorption.
Read food labels to determine the specific calcium levels of these foods.
|Tofu, regular, processed with calcium||½ cup||435|
|Calcium-fortified soy milk||1 cup||250-300|
|Salmon, canned with edible bones||3 ounces||212|
|Calcium-fortified orange juice||¾ cup||200|
|Blackstrap molasses||1 Tbsp||172|
|Pudding, from cook & serve mix||½ cup||150|
|Dried figs||5 pieces||135|
|Tofu, regular (processed without calcium)||½ cup||130|
|Anchovies with edible bones||3 ounces||125|
|Turnip greens, boiled||½ cup||100|
|Milk chocolate bar||1.5 ounce||85|
|Okra, boiled||½ cup||77|
|Kale, boiled||½ cup||70|
|Mustard greens, boiled||½ cup||65|
|Pinto beans||½ cup||45|
Calcium is essential to build and maintain strong bones at all stages of life. Bone growth begins at conception, and bones grow longer and wider until well into the 20s. After this type of growth is complete, bones gain in strength and density as they continue to build up to peak bone mass by about age 35. From this point on, as a natural part of the aging process, bones slowly lose mass. Calcium is essential to slow this natural loss and stave off the onset of osteoporosis—a disease in which bones become fragile and more likely to break.
Tips for Increasing Your Calcium Intake
- When making oatmeal or other hot cereal, use milk instead of water.
- Add powdered milk to hot cereal, casseroles, baked goods, and other hot dishes.
- Make your own salad dressing by combining low-fat plain yogurt with herbs.
- Add tofu (processed with calcium) to soups and pasta sauce.
- If you like fish, eat canned fish with bones on crackers or bread.
- For dessert, try low-fat frozen yogurt, ice cream, or pudding.
- In baked goods, replace half of the fat with plain yogurt.
If you are unable to meet your calcium needs through dietary sources, consider a calcium supplement. Some points to remember when choosing and using a calcium supplement include:
- Check the label because the amount of calcium differs among products.
- Avoid supplements with dolomite or bone meal; they may contain lead.
- Check your vitamin D intake, too. This vitamin is essential for absorption of calcium. Milk is a great source of vitamin D, as is sunlight.
- If you take both calcium and iron supplements or a multivitamin with iron, take them at different times of the day. They can impair each other's absorption. This is also true of chromium, manganese, magnesium, and zinc.
- Do not take more than 500 mg of calcium at a time. Taking the calcium with food can help absorption.
Academy of Nutrition and Dietetics
The Nutrition Source
Harvard School of Public Health
Food and Nutrition
Dietitians of Canada
Bowes A, Pennington J, Church H. Bowes & Church Food Values of Portions Commonly Used. Philadelphia, PA: Lippincott Williams & Wilkins; 1998.
Calcium. EBSCO Natural and Alternative Treatments website. Available at: http://www.ebscohost.com/pointofcare. Updated August 2011. Accessed August 11, 2012.
Calcium. Office of Dietary Supplements website. Available at: http://ods.od.nih.gov/factsheets/calcium.asp. Accessed August 11, 2012.
Calcium intake and supplementation. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed. Updated June 25, 2012. Accessed August 11, 2012.
Dietary reference intakes for calcium and vitamin D. Institute of Medicine website. Available at: http://www.iom.edu/Reports/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D/Report-Brief.aspx?page=1. Published November 30, 2010. Accessed August 11, 2012.
Food and Nutrition Information Center. US Department of Agriculture website. Available at: http://fnic.nal.usda.gov/. Accessed August 11, 2012.
Garrison RH, Somer E. The Nutrition Desk Reference. New Canaan, CT: Keats Publishing; 1995.
Groff JL, Gropper S. Advanced Nutrition and Human Metabolism. Belmont, CA: West Publishing Company; 1995.
Last reviewed August 2012 by Brian Randall, 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.
Copyright © EBSCO Publishing. All rights reserved.
| 3.553064 |
| Risk Factors
Hepatitis B is a liver disease. It can be acute or chronic. Acute hepatitis B usually goes away on its own and may not need treatment.
Chronic hepatitis B is an infection that lasts more than six months. Chronic infection can lead to other health problems. Hepatitis B is treated with antiviral medications.
Copyright © Nucleus Medical Media, Inc.
Hepatitis B is caused a virus. The virus causes swelling and irritation in the liver and makes it difficult for the liver to function normally.
The hepatitis B virus (HBV) is spread by semen, vaginal secretions, saliva, blood, or body fluids from an infected person. The virus can pass from these fluids to your body through an open cut in your skin.
A woman with hepatitis can also pass HBV to her baby during childbirth.
Factors that may increase your chance of hepatitis B include:
- Illicit drug injection use, especially when sharing needles
- Unprotected sexual contact, especially with multiple partners
- Sharing a residence and/or personal items with someone who has HBV
- Stay in hospital or long-term care facility
- Work that includes contact with blood or body fluids, such as health care or public safety workers
- Travel to areas where HBV is common
It is possible that someone infected with HBV may never have symptoms of hepatitis B.
If symptoms do develop, they appear around 60-150 days after exposure. Symptoms may include:
- Fatigue that lasts for weeks or months
- Loss of appetite
- Nausea or vomiting
- Low-grade fever
Yellowing skin and eyes (jaundice)
- Abdominal pain in the upper right side of the abdomen
- Joint pain
- Dark urine and light-colored stool
Chronic hepatitis can lead to serious health problems including:
The doctor will ask about your symptoms and medical history. A physical exam will be done. Hepatitis B is diagnosed with blood tests. Blood tests are also used to monitor changes in the liver.
For chronic cases, a liver
may be needed.
Acute infection may not need any treatment since it usually goes away on its own.
Chronic hepatitis B may be treated with a combination of different antiviral medications. All medications do not work the same in all people. Talk with your doctor about the best treatment plan for you.
Your doctor may also ask that you:
- Avoid alcohol
- Avoid certain medicines, dietary supplements, and herbs
- Contact recent sexual partners so they can be tested and/or treated
To reduce your chance of getting hepatitis B, take these steps:
There is a
to prevent hepatitis B. This vaccine, a series of three injections, is routinely given to newborns. Children and teens who were not vaccinated as babies can still receive the shots.
Other prevention strategies include:
or abstain from sex.
- Limit your number of sexual partners.
Do not inject drugs. If you use IV drugs, get treatment to help you
stop. Never share needles or syringes.
Do not share personal items that may have blood or body fluids on them.
- Make sure a tattoo artist or piercer properly sterilizes the equipment.
Wear gloves when touching or cleaning up body fluids on personal items.
- Cover open cuts or wounds.
- If you are pregnant, have a blood test for hepatitis B. Infants born to mothers with hepatitis B should be treated within 12 hours after birth.
Baker CJ, Pickerling LK, Chilton L, et al. Advisory Committee on Immunization Practices. Recommended adult immunization schedule: United States, 2011.
Ann Intern Med. 2011;154(3):168-173.
Hepatitis B. American Liver Foundation website. Available at:
http://www.liverfoundation.org/abouttheliver/info/hepatitisb. Updated February 17, 2012. Accessed May 1, 2013.
Centers for Disease Control and Prevention website. Available at:
http://www.cdc.gov/hepatitis/HBV. Updated May 16, 2012. Accessed May 1, 2013.
Hepatitis B. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed/what. Updated April 23, 2013. Accessed May 1, 2013.
Vaccine information statement: hepatitis B vaccine. Centers for Disease Control and Prevention website. Available at:
http://www.cdc.gov/vaccines/pubs/vis/downloads/vis-hep-b.pdf. Accessed May 1, 2013.
Vaccine-preventable STDs. Sexually Transmitted Diseases Treatment Guidelines, 2010. Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov/std/treatment/2010/vaccine.htm. Updated January 28, 2013. Accessed May 1, 2013.
Last reviewed May 2013 by Marcin Chwistek, MD; Brian Randall, 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.
Copyright © EBSCO Publishing. All rights reserved.
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The World of Plants
The existence of plants is essential for the survival of living things on the earth. For the importance of this sentence to be fully grasped, we must ask: "What are the most important elements for human life?" Of course, basic needs such as oxygen, water, and nourishment come to mind as the answers to this question. And green plants are the most important factor in ensuring the balance of these basic needs on the earth. And there are other balances in the world, of great importance to all living things, not just human beings, such as temperature control and maintaining the correct proportion of gases in the atmosphere, and again it is green plants which maintain the entire equilibrium.
And the activities of green plants do not end there. As is known, the main source of energy for life on earth is the Sun. But human beings and animals are unable to make direct use of solar energy, because their bodies lack the systems to use this energy as it is. For this reason solar energy can reach human beings and animals as usable energy only through the food produced by plants. For example, while sipping tea, we are actually sipping solar energy, and as we eat bread, we are munching solar energy. The strength in our muscles is really nothing other than solar energy in a different form. Plants store this form of energy for us in the molecules in their bodies by carrying out complicated processes. The position for animals is no different from that of human beings. They are fed by plants, deriving solar energy from the plants' energy, which they store in packets.
Plants being able to produce their own nutrition and maintain themselves, in contrast to other living things, is due to their cell structure, which enables them to employ solar energy directly, unlike human or animal cells. With the help of this structure, plant cells turn energy from the sun into energy which people and animals can absorb through nutrition. They store this energy as food through the special procesesses concealed in their structure. These processes are collectively known as photosynthesis.
The necessary mechanism, or more accurately the miniature factory, by means of which plants are able to carry out photosynthesis, is found in their leaves. The transportation system, with its own very special features, for carrying necessary materials such as minerals and water, functions within plants' stems and roots. The reproductive system too has been specially designed in every species of plant.
There are complex structures within each and every one of these mechanisms. And these mechanisms function in connection with one another. If one is missing, the others cannot carry out their tasks. As an example let us take a plant which just lacks a transport system. It is impossible for such a plant to carry out photosynthesis, because the vessels necessary to carry the essential water are missing. Even if the plant managed to produce food, it would be unable to transport this to other parts of the body, and would eventually die.
As in this example, all the systems present in a plant are obliged to function flawlessly. Any flaws or defects in the existing structure will mean that the plant cannot carry out its functions, and this will result in the death of the plant and the disappearance of the species.
When these structures are studied in detail and in depth in the chapters that follow, a most complex and quite flawless design will emerge. When the variety of plants in the world is considered and evaluated, these extraordinary structures seem even more striking. There are more than 500,000 types of plant in the world. And each species possesses its own special planning within itself and features particular to that species. Together with the same perfect basic systems found in all of them, there is also an unparalleled diversity in terms of reproductive systems, defence mechanisms, colour, and design. The only unchanging thing in all this is the reality that the parts of the plants (leaves, roots, stems) and many other mechanisms, must exist at once and with no defects so that the general system, the body, can function.
Modern scientists attribute to such systems an "irreducible complexity." In the same way that a motor will not work if one of its cogs is missing, in plants the absence of just one system, or a single functional failure in any one of the parts of the system, will lead to the death of the plant.
All of a plant's systems have this feature of irreducible complexity. The complex systems, which must all be present at the same time, and this unbelievable variety bring to mind the question: "How did these perfect systems in plants emerge?"
Once again, let us ask some questions to find the answer to this one. Let us think how the functioning of the most important and best known of the mechanisms in plants, photosynthesis, and the transport systems linked to it, came about.
Can the trees and flowers which we see all around us at all times have themselves formed such perfect systems as to bring about a phenomenon such as photosynthesis, some parts of which are still not fully understood, in their own bodies? Did plants choose to use carbon dioxide (CO2), of the gases in the air, to produce food? Did they themselves determine the amount of CO2 they would use? Could plants have designed those mechanisms which make up the root system and which enable them to take the materials necessary for photosynthesis from the soil? Did plants bring about a transport system where different types of tubes are used for transporting nutrients and water?
As ever, defenders of the theory of evolution searching for an answer to the question of how plants emerged have resorted to "chance" as their only remedy. They have claimed that from one species of plant which came about by chance, an infinite variety of plants have emerged, again by chance, and that features such as smell, taste, and colour, particular to each species, again came about by chance. But they have been unable to give any scientific proof of these claims. Evolutionists explain moss turning into a strawberry plant, or a poplar, or a rose bush, by saying that conditions brought about by chance differentiated them. Whereas when just one plant cell is observed, a system so complex will be seen as could not have come about by minute changes over time. This complex system and other mechanisms in plants definitively disprove the coincidence scenarios put forward as evolutionist logic. In this situation just one result emerges.
Every structure in plants has been specially planned and designed. And this shows us that there is a Superior Intelligence which drew up this flawless plan. And the owner of this superior intelligence, God, the Lord of all the worlds, shows proofs of His flawless creation to human beings. God announces His dominion over living creatures and His incomparable creation in this verse:
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Residuals from treating acid mine drainage can be used as effective, inexpensive adsorbents for agricultural and wastewater discharges, a new study by scientists from the U.S. Geological Survey Leetown Science Center has found.
When acid mine drainage is remediated it is neutralized with a base such as limestone or lime and an iron-rich sludge is formed. The new study published in the Journal Water, Air, and Soil Pollution shows the sludge can efficiently remove phosphorus from agricultural and municipal wastewaters.
The phosphorus that has been adsorbed by the mine drainage residuals can later be stripped from the residuals and recycled into fertilizer, the study says.
"This wonderful result shows the inventive application of some very sophisticated environmental chemistry to create a new life cycle for what otherwise would have been some problematic waste products," said US Geological Survey Director Marcia McNutt in a December 17, 2012 announcement to media about the study. "It sets the bar high for future studies in environmental remediation."
Acid mine drainage is produced whenever sulfide minerals associated with coal and metal deposits are exposed to air and moisture. The resulting acid and dissolved metals are toxic to most forms of aquatic life.
The study, Fixed Bed Sorption of Phosphorus from Wastewater Using Iron Oxide-Based Media Derived from Acid Mine Drainage, is authored by P. L. Sibrell and T. W. Tucker.
Lead author Sibrell said the findings create a “win-win” situation as the mine drainage residuals can be regenerated and reused for a number of additional treatment cycles.
"As environmental scientists, we kind of hesitate to use this analogy, but it really is like killing two birds with one stone," Sibrell said in the study’s announcement. "This new technology could reduce or eliminate the need to dispose of acid mine drainage sludge, instead making that same sludge useful in addressing the urgent need to reduce the amount of phosphorus going into aquatic ecosystems.”
Untreated acid mine drainage has impacted more than 5,000 miles of streams in the Appalachian region, with associated economic impacts of millions of lost dollars in the tourism and sport fishing industries.
Excess phosphorus releases to the environment from agricultural and municipal wastewaters have resulted in significant impairment of aquatic ecosystems such as the Chesapeake Bay and other bodies of water worldwide.
Current technology for the removal of phosphorus from wastewater consists of addition of aluminum or iron salts to precipitate and adsorb phosphorus, but this is too expensive for the low concentrations and high volumes often encountered in many wastewaters. This new technology provides a more efficient and cost-effective option.
REPORT : http://link.springer.com/article/10.1007/s11270-012-1262-x/fulltext.html
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Walker-Warburg syndrome is a congenital disorder of the central nervous system involving fatal neurological lesions. Multiple malformations of the brain, eyes, and muscle tissue distinguish WWS from similar malformation syndromes. It is also known by the acronym HARD +/- E syndrome (hydroencephalus, agyri, retinal dysplasia, plus or minus "e" for encephalocele).
Affected individuals typically show a combination of severe brain, eye, and muscle defects. Multiple malformations of the brain include type II lissencephaly, a condition in which the brain lacks normal convolutions and is unusually smooth without folds. Eighty-four percent of the babies with WWS have macrocephaly (an enlarged head). In half of these cases, the macrocephaly is apparent at birth, and in a quarter of the cases it develops postnatally. Hydrocephalus, or excessive accumulation of cerebrospinal fluid around the brain, occurs in 95% of infants with WWS. This fluid fills abnormally large ventricles or spaces in the brain. Fifty percent of affected infants have an encephalocele, or gap in the skull that does not seal. The meninges or membranes that cover the brain may protrude through this gap. The formation of an encephalocele may be associated with the failure of the neural tube to close during development of the fetus. A malformed cerebellum characterizes the syndrome as well as distinct muscle abnormalities, including congenital muscular dystrophy.
Ocular defects occur in 100% of infants with WWS. The most common are abnormally small eyes and retinal abnormalities, which arise from the improper development of the light sensitive area at the back of the eye. Cataracts may also be present and more than three quarters of the infants born with WWS have a defect in the anterior chamber of the eye. WWS syndrome leads to severely retarded mental development and is often lethal in infancy.
WWS is inherited in an autosomal recessive pattern. Offspring of parents who have had one affected infant have a 25% chance of having WWS. The locations of the causitive genes remains unknown.
WWS is extremely rare. Cases described in the literature cite siblings with WWS born to consanguineous (closely related) parents as well as cases in families not known to be at risk.
Signs and symptoms
Clinical signs include a malformed head, small eyes, cataracts, retinal abnormalities, and muscle weakness. An
Prenatal ultrasound can reveal some of the brain anomalies associated with WWS, most commonly hydrocephalus and encephalocele. Lissencephaly can not be diagnosed prenatally as normal fetal brains appear smooth. After birth, diagnosis is made on the basis of physical features and ultrasound exams. MRI may be used to confirm the smooth brain feature or type II lissencephaly typical of WWS. Genetic analysis helps distinguish WWS from Fukuyama-type congenital muscular dystrophy (FCMD), which has numerous similar features. WWS can be differentiated from other syndromes that display hydrocephalus or encephalocele by the presence of eye abnormalities including retinal defects, cataracts and anterior chamber defects. Genetic testing for Fukuyama-type congenital muscular dystrophy distinguished this from WWS.
Treatment and management
The severe malformations of the brain defy treatment and many infants with WWS die within the first year of life. Supportive care is required to provide comfort and nursing needs. Seizures may be controlled with medication. Shunting may be required to control the hydrocephalus. A shunt or short plastic tube can be placed to divert the excess cerebral spinal fluid to another area of the body where it can ultimately be absorbed by the body.
Genetic counseling is recommended for families at risk.
Patients have a very limited life expectancy and the syndrome is generally considered lethal. Most patients die before the age of two.
Menkes, John H., and Harvey B. Sarnat. Child Neurology. 6th ed. Philadelphia: Lippincott, Williams & Wilkins, 2000.
Volpe, Joseph J. Neurology of the Newborn. 4th ed. Philadelphia: W.B. Saunders, 2001.
Gasser, B., et al. "Prenatal Diagnosis of Walker-Warburg Syndrome in Three Sibs." American Journal of Medical Genetics 76 (March 1998): 107-10.
Hung, N.A., et al. "Gonaddoblastoid Testicular Dysplasia in Walker-Warburg Syndrome." Pediatric Developmental Pathology 1 (September-October 1998): 393–404.
Vasconcelos, M.M., et al. "Walker-Warburg Syndrome. Report of Two Cases." Fetal Diagnostic Therapy 14 (July-August 1999): 198–200.
Lissencephaly Network, Inc. 716 Autumn Ridge Lane, Fort Wayne, IN 46804-6402. (219) 432-4310. Fax: (219) 432-4310. [email protected]. <http://www.lissencephaly.org>.
National Hydrocephalus Foundation. 12413 Centralia, Lakewood, CA 90715-1623. (562) 402-3523 or (888) 260-1789. [email protected]. <http://www.nhfonline.org>.
National Organization for Rare Disorders (NORD). PO Box 8923, New Fairfield, CT 06812-8923. (203) 746-6518 or (800) 999-6673. Fax: (203) 746-6481. <http://www.rarediseases.org>.
"Fukuyama Congenital Muscular Dystrophy." OMIM–Online Mendelian Inheritance in Man. <http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=253800>.
"Muscular Dystrophy, Congenital, With Severe Central Nervous System Atrophy and Absence of Large Myelinated Fibers." OMIM–Online Mendelian Inheritance in Man. <http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=601170>.
"Walker-Warburg Syndrome." OMIM–Online Mendelian Inheritance in Man. <http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=236670>.
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Coarctation of the aorta (CoA) is a congenital malformation of the aorta. The condition is also known as aortic coarctation. Either name indicates a constriction of the aorta.
The aorta is the largest artery in your body. With a diameter about the size of a garden hose, the aorta leaves the left ventricle of the heart and runs through the middle of your body, through the chest and into the abdominal area. There, it branches out to deliver freshly oxygenated blood to your lower limbs. A constriction or narrowing of this important artery can result in decreased flow of oxygen.
In CoA, the constricted part is generally near the top of the aorta and acts like a kink in a hose. As your heart tries to pump oxygen-rich blood to the body, the blood has trouble getting through the kink. This causes high blood pressure in the upper parts of your body and reduced blood flow to the lower parts of your body.
CoA is generally diagnosed and treated shortly after birth through surgery. These children usually grow up to lead normal, healthy lives. However, if your child is not diagnosed with CoA until he or she is older, your child is at risk for high blood pressure and heart problems. He or she may require close medical monitoring.
Without treatment, CoA patients generally die in their 30s to 40s of heart disease or from complications of chronic high blood pressure.
CoA is one of several common types of congenital heart malformations. CoA may occur alone, or together with other abnormalities in the heart. CoA is seen more frequently in boys than girls. It is also associated with other congenital heart defects, such as Shone’s complex and DiGeorge syndrome. While it is known that CoA begins during fetal development, its causes are still not fully understood.
In the past, doctors thought that CoA occurred more often in whites than in other races. However, more recent research suggests that differences in the prevalence of CoA may be due to different rates of detection. Studies suggest and that all races are equally likely to be born with the defect.
Fortunately, the chances of your child being born with CoA are fairly low. CoA affects only about 6 to 8 percent of all children born with heart defects. And congenital heart defects only occur in approximately .009 percent of all babies born each year.
Symptoms in Newborns
Symptoms in newborns vary with the severity of the constriction of the aorta. About half of newborns with CoA exhibit no symptoms. The rest may have trouble breathing and be poor feeders. Other symptoms are sweating, high blood pressure, and congestive heart failure.
Symptoms in Older Children and Adults
In mild cases, children may exhibit no symptoms until later in life. When symptoms do begin to show, they can include:
CoA is usually discovered during the newborn’s first examination. Your doctor may detect differences in blood pressure between the baby’s upper and lower extremities, or hear characteristic sounds of the defect when listening to your baby’s heart.
CoA is generally treated soon after birth using balloon angioplasty or surgery. Balloon angioplasty involves inserting a catheter inside the constricted artery and then inflating a balloon inside the artery to widen it. Surgical treatment may involve removing and replacing the “crimped” portion of the aorta. The surgeon may instead choose to bypass the constriction with a graft or creating a patch over the narrowed portion to enlarge it.
Adults who received treatment in childhood may require additional surgery later in life to treat any reoccurrence of CoA. Additional repairs may be needed to the weak area of the aortic wall. Left untreated, persons with CoA generally die in their 30s or 40s of heart failure, ruptured aorta, stroke, or other conditions.
Chronic high blood pressure associated with CoA increases the risks of heart damage, aneurysms, stroke, and premature coronary artery disease. Chronic high blood pressure can also lead to kidney and liver failure, and loss of eyesight through retinopathy. Patients with CoA may need to take drugs, such as ACE (angiotensin-converting-enzyme) inhibitors and beta-blockers to control high blood pressure.
CoA patients should follow a healthy lifestyle. Moderate daily aerobic exercise is helpful for maintaining healthy weight, cardiovascular health, and controlling blood pressure. Strenuous exercise, such as weightlifting, put additional stress on the heart and should be avoided. CoA patients should minimize their intake of dietary salt and fat. Anyone with CoA should NEVER smoke any kind of tobacco products.
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Middle rectal artery
Within the body's pelvic region, the middle rectal artery serves oxygenated blood to the rectum. However, there are anatomical variances between males and females. For men, the artery branches into blood vessels that serve the prostate as well as the seminal vesicles. In women, the artery branches into vessels that run into the vagina. In both sexes, the artery arises from the internal iliac artery. Also, the rectum is the end of the digestive tract. The supply of oxygenated blood that assists in the final stages of digestion is left over ingested matter processed into feces to be expelled from the body. The middle rectal artery has venal counterparts in the middle rectal veins. These vessels actively drain deoxygenated blood from the area and move it to the internal ileac vein. From there, the deoxygenated blood moves through venal circulatory system until it ends up in the heart via the inferior vena cava. The right side of the heart then pumps it into the lungs for fresh oxygen.
Written and medically reviewed by the Healthline Editorial Team
In Depth: Middle rectal artery
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Whenever cardiac conditions develop these conditions, weaken or damage your heart, which leads to heart failure. In a weakened condition, the heart over time can no longer keep up with even the normal demands placed on it. The ventricles may become stiff and not fill properly between beats. The heart ventricles stretch (dilate) to the point that the heart cannot pump blood efficiently throughout your body. The failing pump causes blood and fluid to back up throughout your circulatory system. The circulatory system consists of your lungs, legs, feet and ankles. The kidneys retain excess water and sodium. All this builds up is the congestive part of your heart failure. The lung congestion occurs only with left-sided heart failure with fluid backing up into the lungs. The most common cause of right sided heart failure is left sided heart failure.
When the fluid fills up the left side of the heart the pressure in the lungs passes to the right side of the heart, which then fails. The fluid then collects in the abdomen and lower extremities which all leads up to heart failure. Heart Failure develops quickly after a heart attack. The heart failure can also develop after years of high blood pressure or coronary artery disease. A defective valve may cause heart failure. A heart valve replacement in this case will prevent heart failure. A specialist normally does the surgical part, which is a cardiologist.
Many times people think that such things cause heart failure as smoking, being overweight or eating foods high in cholesterol and fat but there is a condition known as idiopathic dilated cardiomyopathy were the heart weakens without explanation. This condition will also cause you congestive heart failure if not properly taken seriously.
You might be suffering from if you have heart failure several conditions. These conditions can weaken your heart over time and be present without you being aware that you have the problem. The follow is a brief description of some conditions that affect the heart:
- The most common cause of heart failure is Coronary artery disease. A process called atherosclerosis, which is a build up of fatty deposits in the arteries. This fatty build up causes the blood to narrow a process called plaque, which leaves chronically deprived of oxygen-rich blood pump less vigorously. A heart attack occurs if an unstable plaque not function well it will cause a blood clot in turn completely blocks the blood flow to an area of the heart muscle. This is one of the most common causes of heart failure.
- There are several other reasons that might cause heart failure but we shall discuss the next highest reason for now. High Blood Pressure (hypertension) is the force of blood pumped by your heart through your arteries. When your blood pressure is high then your heart has to work harder causing failure.
Take your cardiologists advice watch your weight and exercise your on the way to a heart healthy way of life.
Frank Mangano’s e-book, “The Blood Pressure Miracle”, is the best way to naturally and permanently lower your blood pressure without using any pharmaceutical drugs. The program in this book is a unique, all-natural system for lowering your blood pressure that is not based on a single approach such as stress reduction, or herbs or special foods or exercise. It’s actually a combination of every method that has ever been scientifically proven to work, complied into one comprehensive lifestyle program. This is why the program has been so successful for so many people. The best part of the program is the 60-day plan that’s included in the appendix. It makes the whole program a no brainer to make a part of your daily life because Frank gives you a single change you can make to your daily routine, one day at a time. If you change the little things one at a time, they all add up and the results over the weeks and months can be astonishing. Frank also offers an unconditional, risk-free 60-day guarantee, which is very generous and shows that he has faith that his 60 day plan will lower your blood pressure or else you get your money back. If you want to purchase Frank Mangano’s e-book, “The Blood Pressure Miracle” and learn more about Frank’s natural blood-pressure reducing methods, then please click here to get more information!
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One of the main morphological differences between men and women is the greater amount of fat that women carry; this softens the outline of the muscles, more or less erases the osseous indicators, and rounds out the surfaces while creating characteristic folds and grooves.
Fat in normal women represents between 18% and 20% of body weight, whereas in men it represents only 10% to 15%. The reason for this difference is that women at some point in their lives may nourish a fetus and then a baby from their own reserves, so women have to stock energy in the form of fat in anticipation of future pregnancies (and must stock even more energy during the last two trimesters of pregnancy).
For various reasons, different fat distributions occur in women according to climate. In hot countries, the fat is localized on the buttocks (black Africans), on the hips (Mediterraneans), and around the navel (certain Asians). This distribution avoids covering the woman with a hot coat of fat that would be difficult to bear and inefficient for thermoregulation during hot periods. In cold countries, the distribution of fat is more uniform, which provides for better protection during rigorous winters. However the fat is distributed, its main function is for the survival of the species as it provides for survival of the woman and her offspring during times of scarcity.
It is important to note that all healthy people have fat reserves necessary for the proper functioning of their bodies. Obsession with obesity or the need to follow deviant aesthetic fashions should not lead to the complete elimination of fat. In fact, the almost complete disappearance of fat can lead to serious hormonal problems involving the cessation of the period (amenorrhea, which is a temporary absence of ovulation and therefore momentary sterility), as this means has been put in place during evolution to avoid bringing progeny into the world that the female could not nourish with her own organic reserves.
Primary Fat Deposits
Fat reserves accumulate in very specific areas on the body. Generally they avoid the flexion folds at the joints in order not to interfere with movement. Fat accumulations are often distributed the same in both sexes; the main difference is in the greater development on certain areas in women.
1. The Buttocks
The buttock region can be quite prominent in women; this is almost entirely due to fat that is contained by the gluteal fold. Besides its role as an energy reserve, this concentration protects the anal area and helps make the sitting position more comfortable by cushioning the direct contact between the bones (ischial tuberosities) and the ground or supporting surface.
The Gluteal Fold
The gluteal fold is made up of tough, fibrous tracts that connect the deep surface of the skin in the gluteal area to the ischium. The main consequence of this fibours attachement is to contain the fat in a sort of pocket, which prevents it from falling down against the back of the thigh while at the same time increasing the volume of the buttock. When certain people age, this fat empties and the bottom of the buttock withers, even going so far as to hang down. Only appropriate training of the buttock area will compensates for the disappearance of fat and the loss of tone through muscle development that maintains the buttocks from the inside.
2. Low Back
Second in importance, this concentration merges with the gluteal area so that the buttock increases in height until it seems to go up to the waist.
3. Below the Trochanter, or “Riding Breeches”
Frequently found in Mediterranean women, this concentration can be quite bulky. Located on the superior part of the lateral thigh just below the depression of the greater trochanter, it blends with the fatty tissue of the anterior surface of the thigh and, at the posterior, with that of the buttocks. When there is a lot of fat in this area we often observe many more or less deep depressions on the surface of the skin, referred to as a “pitted” or “cottage cheese” surface. This is due to inelastic fibrous tracts that, like little cables, connect the deep surface of the skin at the level of the depressions to the enveloping aponeurosis of the muscle, with the adipose tissue creating bumps or bulges in between (a quiltlike phenomenon).
4. Between the Thighs
Relatively common in women, fat in this location plays an important aesthetic role in that it fills the space between the two thighs; it is often more noticeable in women than in men.
5. Around the Navel
As in the subtrochanteric location, the periumbilical concentration is one of the rare fat deposits that is also found in thin women.
This triangular concentration is known as the “mount of Venus.” It protects the symphysis pubis from blows.
In women, the knee is often a location of fat concentration, especially on the medial region.
8. Posterior-Medial Part of the Upper Arm
Especially developed in women, this concentration, besides its energetic role, protects the superficial nerves and arteries in the medial and superior area of the arm.
The breast is composed of fat enclosing the mammary glands, the whole being held together by a web of connective tissue resting on the pectoralis major. Note that men also have glands and mammary fat (atrophied).
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We think of the five senses as exclusive to living things
Processing sights and sounds requires eyes, ears and, most important, a brain—right? But what if your hardware shared your senses?
In the era of cognitive computing, systems learn instead of passively relying on programming. As a result, emerging technologies will continue to push the boundaries of human limitations to enhance and augment our senses with machine learning, artificial intelligence (AI), advanced speech recognition and more. No need to call for Superman when we have real super senses at hand.
This year IBM presents The 5 in 5 in five sensory categories, through innovations that will touch our lives and see us into the future.
From IBM's Chief Innovation Officer
Read what he says about The 5 in 5
The poll is closed, but you can follow up and continue the discussion on IBM's People for a Smarter Planet Facebook page.
Touch: You will be able to touch through your phone
In the 1970s, when a telephone company encouraged us to "reach out and touch someone," it had no idea that a few decades later that could be more than a metaphor. Infrared and haptic technologies will enable a smart phone's touchscreen technology and vibration capabilities to simulate the physical sensation of touching something. So you could experience the silkiness of that catalog's Egyptian cotton sheets instead of just relying on some copywriter to convince you.
Associate Director, IBM Research, Retail Analytics
Sight: A pixel will be worth a thousand words
Recognition systems can pinpoint a face in a crowd. In the future, computer vision might save a life by analyzing patterns to make sense of visuals in the context of big data. In industries as varied as healthcare, retail and agriculture, a system could gather information and detect anomalies specific to the task—such as spotting a tiny area of diseased tissue in an MRI and applying it to the patient's medical history for faster, more accurate diagnosis and treatment.
Senior Manager, Intelligent Information Management
Hearing: Computers will hear what matters
Before the tree fell in the forest, did anyone hear it? Sensors that pick up sound patterns and frequency changes will be able to predict weakness in a bridge before it buckles, the deeper meaning of your baby's cry or, yes, a tree breaking down internally before it falls. By analyzing verbal traits and including multi-sensory information, machine hearing and speech recognition could even be sensitive enough to advance dialogue across languages and cultures.
IBM Research Scientist
Taste: Digital taste buds will help you eat smarter
The challenge of providing food—whether it's for impoverished populations, people on restricted diets or picky kids—is in finding a way to meet both nutritional needs and personal preferences. In the works: a way to compute "perfect" meals using an algorithmic recipe of favorite flavors and optimal nutrition. No more need for substitute foods when you can have a personalized menu that satisfies both the calorie count and the palate.
IBM Research Scientist
Smell: Computers will have a sense of smell
When you call a friend to say how you're doing, your phone will know on the full story. Soon, sensors will detect and distinguish odors: a chemical, a biomarker, even molecules in the breath that affect personal health. The same smell technology, combined with deep learning systems, could troubleshoot operating-room hygiene, crops' soil conditions or a city's sanitation system before the human nose knows there's a problem.
Research Manager, Physical Analytics
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All You Want to Know : Pigments and Cooking
There are several characteristics of vegetables that influence the way we cook them. One of these is colour. No matter what colour a raw vegetable is, we want to preserve as much as possible of that colour. Vegetables may be grouped by colour into four categories:
RED: beets, red cabbage, red beans
GREEN: beans, broccoli, asparagus, peas artichokes, okra, brusselsprouts, spinach, parsley.
YELLOW: carrots, yams, squashes, sweet potatoes,
WHITE: potatoes, turnips, celery, cauliflower, onions, mushrooms, cucumbers, zucchini
These colours come from the pigments in the vegetables. Certain pigments react to acids, alkalis, or heat during cooking, undergoing chemical changes that cause the vegetable to change colour. It is important to know which pigments are susceptible to colour change and how to deal with them during the process of cooking.
Red Vegetables: The pigments in red vegetables are known as anthocyanins. These pigments are red in an acid medium but will change to blue or purple in an alkaline medium. They are also water soluble and therefore can draw out the colour into the cooking medium. egs.: Beetroot- one would have to cook it with the skin on, so that the colour does not leach out into the water. Cook covered so the acids do not evaporate. Red cabbage in an alkaline medium will not only lose its redness, but will also turn purple, blue or green.
Green Vegetables; Chlorophyll’s action to acid is the opposite of the red vegetables. They keep their colour best if cooked in a slightly alkaline medium. It would seem ideal to include baking soda in the cooking medium to increase alkalinity-Not So! If only colour were the quality desired then this approach would be fine. Baking soda has other less desirable effects. It tends to destroy such nutrients as vitamins, and also makes the vegetables more mushy and sometimes gives it a bitter taste. Note- the dark green colour in canned green vegetables is because of prolonged cooking at high temperatures to prevent botulism.
Yellow Vegetables; The pigments here are known as carotene’s, and there are several types which range from the yellow in corn, to the orange in carrots, to the red in tomatoes. They do not suffer any colour loss in acidic or alkaline medium, however if the vegetable is overcooked then it can lose some amount of colour.
White Vegetables; The Flavones are the pigments in these veggies! They remain white in acid, but turn yellow in an alkaline medium, so a bit of lemon juice or a cover on the pot is in order.
NOTE; the pH value of a material indicates its acidity or alkalinity. Acids are characterized by hydrogen ions(H+), while alkalis or bases by hydroxyl ions (OH). To test the pH value of a material a scale of numerical value ranging from 1 (for very acidic) to 14 (for very alkaline) has been developed and is in common use. The whole pH scale has been so devised that each whole step represents a tenfold change in the degree of acidity. Thus a solution with a pH of 5 is ten times more acidic than a solution with a pH of 6. Similarly a solution with a pH of 4 is hundred times more acidic than a solution with a pH of 6. -salad greens go limp and discolour when salad dressings are poured over them, a long time before service. This is because the acids first of all destroy the chlorophyll. The reaction here takes a long time, because there is no heat involved in this reaction. Secondly the acids and the seasonings in the dressings draw out the moisture in the leaves- this leaves the salad all limp. -fresh milk has a pH of 6.6. As it ages the milk sugar lactose is converted to lactic acid, and at a pH of around 6.4 the change in the pH along wit the other changes can be detected in taste. We say that milk is sour at a pH of around 5 where the coagulation of protein takes place and the milk has curdled. -table wines have a pH of between 3 to 3.5 and beers a pH of about 4 to 5 . -the pH of living muscle is about neutral, but becomes acidic after death due to the formation of lactic acid from glycogen. -did you know that egg white is alkaline while egg yolk is acidic?
Image Credit: almightydad.com
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A first-degree burn is the least serious type of burn in which only the outer layer of skin is burned, and not all the way through. The skin is usually red, swollen and possibly painful. As long as it doesn’t involve a substantial portion of skin in places like the face or major joints, a first-degree burn can be treated as a minor burn. Even these “minor” burns, however, should be treated correctly to prevent complications. Whether you live alone or with a large family, it’s important to know how to prevent common household burns, as well as how to treat minor burns.
Safe Kids Canada, the national injury prevention program of The Hospital for Sick Children, reminds parents and caretakers that children are particularly vulnerable to burns because their skin is thinner than an adult's skin. A child's skin burns 4 times more quickly and deeply than an adult's at the same temperature. Scalding injuries, caused by hot water and liquids, are unfortunately common. To avoid these types of burns, be sure to keep cooking materials and hot liquids out of reach when children are nearby. Always test the temperature of bath water and any drinking liquids before they come in contact with a child.
If a minor burn does occur, use these recommendations:
• Cool the burn by holding the injury under cool – not cold – running water for 10 or 15 minutes or until the pain subsides. You can also immerse the burn in a bowl of cool water or use a cold compress.
• Don't put ice on the burn.
• Cover the burn with a sterile gauze bandage. Don't use fluffy cotton or other materials that easily stick to the wound. Wrap the gauze loosely to avoid putting pressure on burned skin.
• Take an over-the-counter pain reliever such as aspirin, ibuprofen, naproxen or acetaminophen. Use caution when giving aspirin to children and teenagers, and call your doctor with any questions or concerns.
• Don't apply butter or ointments to the burn (unless a specific ointment or cream is advised by your healthcare provider).
• Don't break blisters.
Most minor burns heal on their own. If your burn doesn’t heal within 10 days to two weeks, or if you experience a fever, excessive swelling or blisters filled with coloured fluid, however, seek immediate medical attention. For more information about burns and first aid, visit Safe Kids Canada at www.safekidscanada.ca/Parents/Safety-Information/Scalds-and-Burns/Index.aspx.
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Frozen vegies contain more nutrients that fresh
Frozen vegetables can often contain more nutrients than fresh vegetables, a report has claimed. Up to 45 per cent of important nutrients are lost in fresh vegetable by the time they are consumed.
It can take up to two weeks for fresh produce to reach the table from being picked although the survey found that 80 per cent of shoppers thought the fresh vegetables in supermarkets were less than four days old.
Produce which is frozen soon after being picked with have more nutrients sealed in, scientists from the Institute of Food Research claimed.
Meanwhile after 16 days green beans have lost 45 per cent of nutrients, broccoli and cauliflower 25 per cent, garden peas up to 15 per cent and carrots 10 per cent.
The research was carried out by the Institute on behalf of Birds Eye the frozen food manufacturer.
Nutritionist Dr Sarah Schenker said: “The nutritional content of fresh vegetables begins to deteriorate from the minute they are picked. This means that by the time they end up on our plate, although we may think we’re reaping the vegetable’s full nutritionalb enefits, this is often not the case.”
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Millions of tons of debris washed out to sea from north-east Japan by the March 11 tsunami has embarked on a 10-year circuit of the Pacific, endangering shipping and wildlife.
The French environmental group Robin des Bois estimates that a large percentage of the 25 million tons of debris created by the magnitude 9 earthquake and the tsunami that it triggered has been sucked out to sea.
Insurance costs for damage caused across Japan likely to be in region of £9bn adding further blow to indebted economy
A firefighter looks at burned-out vehicles at Hitachi port, north-eastern Japan, the day after the giant quake and tsunami struck. Photograph: AP
Industry in the world’s third-largest economy all but ground to a halt following the earthquake, as manufacturers ranging from Toyota to Nissan, Sony, Fuji and brewers Kirin and Sapporo shut down their operations in Japan to assess damage and allow staff to check on their families.
The quake is a shattering blow to Japan’s already heavily indebted economy, which recently endured a downgrade in its credit rating. Finance minister Yoshihiko Noda raised the prospect of an emergency budget to cope with reconstruction costs, but suggested that this would be hard to compile before the end of March.
JAKARTA (Reuters) – Indonesia’s Mount Merapi volcano erupted on Monday for the third time in a week, driving the number of refugees to almost 70,000, as the death toll from a tsunami thousands of kilometers to the west rose to 431, officials said.
The fresh eruption forced a thick ash cloud around 1.5 kilometers (0.9 miles) into the air above Merapi, which sits on the outskirts of Yogyakarta city in Central Java, and caused panicked residents to flee villages on the slopes of the mountain for safety shelters.
The National Disaster Mitigation Agency said that 38 people have been killed and 69,533 evacuated since Merapi began erupting last week, while Indonesia’s vulcanology agency warned that flights around Yogyakarta may be disrupted.
Dozens of injured survivors of a tsunami off western Indonesia today languished at a sorely strapped hospital alongside a newly orphaned 2-month-old baby found in a storm drain, as the death toll from the disaster rose above 400.
The injured lay on mats or the bare floor as rainwater dripped onto them from holes in the ceiling and intravenous cords hung from plastic ropes strung from the rafters. The baby, its lungs filled with fluid and with cuts on its face, blinked sleepily in a humidified crib.
“We need doctors, specialists,” nurse Anputra said at the tiny hospital in Pagai Utara — one of the four main islands in the Mentawai chain slammed by Monday’s tsunami.
The toll from the tsunami and the 7.7-magnitude earthquake beneath the Indian Ocean that spawned it rose to 408 today as officials found more bodies, and 303 people were still missing, said Agus Prayitno, of the West Sumatra provincial disaster management center. Rescue teams “believe many, many of the bodies were swept to sea,” said Harmensyah, the disaster center’s chief.
Along with the 33 people killed by a volcano that erupted Tuesday more than 800 miles (1,300 kilometers) to the east in central Java, the number of dead from Indonesia’s twin disasters this week has now reached 441.
The downtown of Fagatoga was flooded when a tsunami hit American Samoa early on Tuesday. (AP)
SYDNEY, Australia — A powerful tsunami generated by an undersea earthquake killed more than two dozen people and wiped out several villages in the tropical islands of American Samoa and Samoa early on Tuesday there, according to officials and local residents who were working to assess the damage.
The earthquake struck around dawn, as many residents were preparing for work and getting their children ready for school. Officials said they expected heavy damage in the southern parts of Samoa and American Samoa, a United States territory with about 60,000 residents.
Damaged telephone lines on both islands hampered efforts to count the casualties and assess the destruction from the earthquake, with a magnitude of 8.0. It struck below the ocean about 120 miles southwest of American Samoa and 125 miles south of Samoa, and it was centered only 11 miles below the seabed, according to the United States Geological Survey.
At least 14 people were killed in American Samoa, the territory’s governor, Togiola T. A. Tulafono, said at a news conference in Hawaii. The toll could rise as emergency workers gain access to damaged areas, he and other officials said.
Food riots have broken out across the globe destabilizing large parts of the developing world. China is experiencing double-digit inflation. Indonesia, Vietnam and India have imposed controls over rice exports. Wheat, corn and soy beans are at record highs and threatening to go higher still. Commodities are up across the board. The World Food Program is warning of widespread famine if the West doesn’t provide emergency humanitarian relief. The situation is dire. Venezuelan President Hugo Chavez summed it up like this, “It is a massacre of the world’s poor. The problem is not the production of food. It is the economic, social and political model of the world. The capitalist model is in crisis.”
Right on, Hugo. There is no shortage of food (This is disinformation – The Infinite Unknown); it’s just the prices that are making food unaffordable. Bernanke’s “weak dollar” policy has ignited a wave of speculation in commodities which is pushing prices into the stratosphere. The UN is calling the global food crisis a “silent tsunami”, but its more like a flood; the world is awash in increasingly worthless dollars that are making food and raw materials more expensive. Foreign central banks and investors presently hold $6 trillion in dollars and dollar-backed assets, so when the dollar starts to slide, the pain radiates through entire economies. This is especially true in countries where the currency is pegged to the dollar. That’s why most of the Gulf States are experiencing runaway inflation. Continue reading »
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Human expansion and interference have detrimental effects as civilizations continue to encroach on previously undisturbed habitats. As a result, many species of animals and plants must struggle to survive.
Biodiversity reveals the important role each of these life forms plays in its ecosystem as well as the irreversible and extensive consequences that would result from a massive loss of biodiversity. It explores the ecological and evolutionary processes, how these processes depend on the cohabitation of a wide range of life forms within an ecosystem, and how the existence of these diverse organisms maintains a crucial stability in the natural world. Beginning with an introduction to biodiversity, this new volume discusses its importance and history, the difficulties in maintaining it, and past and current efforts to protect ecosystems from greater destruction. It examines five specific case studies, including the United States, Indonesia, New Zealand, Madagascar, and Costa Rica, describing the current status and history of biodiversity, obstacles, and conservation efforts in the country at hand.
Maps. Index. Bibliography. Glossary. Chronology. Tables and graphs.
About the Author(s)
Natalie Goldstein is a freelance writer who has written numerous books for the educational market, including textbooks and teacher's guides for the middle school and encyclopedias for the high school. She also wrote Globalization and Free Trade and Global Warming in the Global Issues series.
Foreword author Julie L. Lockwood is director of the graduate program in ecology and evolution and associate professor in the Department of Ecology, Evolution, and Natural Resources at Rutgers University. She is the coauthor of Avian Invasions: The Ecology and Evolution of Exotic Birds and Invasion Ecology.
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Last reviewed by Faculty of Harvard Medical School on January 24, 2013
By Harvey B. Simon, M.D.
Harvard Medical School
Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death in the United States. It's also the only disease among the top 10 killers that is seeing an increase in deaths each year. About 15 million Americans suffer from COPD. Men are affected about twice as often as women because male smokers have outnumbered female smokers.
COPD is not curable, but it is treatable. Lifestyle changes and medication can help people cope with chronic lung disease and live longer, fuller lives. But as you'll see, most cases of COPD can be prevented.
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What Is COPD?
COPD refers to chronic illnesses that block the flow of air and make breathing difficult. The two major forms of COPD are chronic bronchitis and emphysema. In both, narrowed air passages or bronchi make it hard to exhale. (Bronchi are wider during inhalation and narrow during exhalation.) Narrowed bronchi also cause asthma, but the narrowing is temporary and reversible. In COPD, it's permanent.
In chronic bronchitis, the mucous glands in the air passages are enlarged and produce too much mucous, which narrows the bronchi. In emphysema, the narrowing of the bronchi is caused by damage to the lung tissue and is more severe than in chronic bronchitis. Most patients with COPD have a mixture of chronic bronchitis and emphysema. Inflammation triggered by irritants that are inhaled also contributes to COPD. White blood cells try to fight off the irritation, but instead of controlling the damage caused by the irritant, they release chemicals that damage and eventually destroy lung tissue.
Smoking causes about 85% of COPD cases. Heavy smokers have the highest risk of developing COPD. Secondhand smoke and other inhaled toxins can cause COPD in some nonsmokers. In others, an inherited protein deficiency is to blame. But in some cases, no cause is apparent.
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What Are the Symptoms of COPD?
COPD starts gradually and progresses slowly over time. That's why the number of cases of COPD continues to increase years after many American men quit smoking.
At first, there are no symptoms. But little by little, symptoms appear, usually in middle age. A morning "smoker's cough" is often the first complaint. The cough gradually gets worse and occurs throughout the day. Next, shortness of breath develops. In the beginning, it only occurs during exercise, but as the disease progresses, breathing becomes a chore even at rest. Wheezing is another common symptom. Most patients also become tired and weak.
Patients with chronic bronchitis have a recurrent cough that brings up large amounts of thick, discolored phlegm almost every day for three months or longer. Over time, the lung disease puts a strain on the heart and men may develop cor pulmonale, a form of congestive heart failure. As a result, they accumulate fluid and gain weight. Their lips and skin may eventually turn bluish due to low blood oxygen levels.
Men with emphysema have a scant and dry cough, severe shortness of breath and they breathe faster than normal. Their skin stays pink and they dont retain fluid, but their appearance changes: they lose weight, their muscles tend to waste away, and they develop large, barrel-shaped chests.
Most patients with COPD have symptoms of both chronic bronchitis and emphysema. In addition to daily symptoms, most patients have two to three exacerbations each year. These are abrupt flares that are often triggered by lung infections. Symptoms get much worse and aggressive treatment is needed.
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How Is COPD Diagnosed?
The best way to diagnose COPD is with a simple, safe lung-function test, called the forced expiratory volume at one second (FEV1). It measures the amount of air you can breathe out with maximum effort in one second. Doctors can also use this test to check the results of treatment. X-rays, blood oxygen mearurements, and other tests may also help.
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People with COPD can take steps to control symptoms, and minimize complications and disability. The first rule is the most important: Avoid tobacco and secondhand smoke. This is a hard and fast rule. There are no exceptions.
Good nutrition is also important. A diet high in fruits, vegetables, and fish may actually help the lungs. There is no evidence that vitamin supplements help. In fact beta-carotene actually increases a male smoker's risk of lung cancer. Patients with chronic bronchitis and heart strain must avoid sodium (salt). Men with severe emphysema may benefit from high-calorie nutritional supplements. Drinking plenty of fluids will help keep phlegm loose and make it easy to clear out by coughing.
A program of low-to-moderate intensity exercise can help the muscles get the most from the oxygen that damaged lungs can deliver. Walking is best. Start with 5 just minutes of walking three to four times a day and build up to 45 minutes a day. Patients with severe COPD or heart disease may also need a structured pulmonary rehabilitation program, which can teach breathing exercises that strengthen chest muscles.
Preventing infection is essential. Be sure your flu and pneumonia shots are up to date. Keep your distance from folks with respiratory infections. Wash your hands carefully with an alcohol-based hand rub.
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Medications for COPD
Prescription medications can do a lot for patients with COPD. Your doctor will explain the benefits and possible side effects. Here is a summary of the major groups of medications.
- Bronchodilators - These relax the muscles in the walls of the bronchi, widening the tubes and easing the passage of air. The most popular short-acting bronchodilator is albuterol (Proventil). It is inhaled through a metered-dose inhaler (MDI) up to four times a day for quick relief of wheezing, coughing, or shortness of breath. Patients with mild COPD may need only a short-acting bronchodilator, but patients with more advanced disease also benefit from a long-acting bronchodilator. They help prevent symptoms rather than provide immediate relief. Salmeterol (Serevent) or formoterol (Foradil) can be inhaled twice a day as a spray or from a dry powder inhaler (DPI). Patients taking salmeterol or formoteral should continue using their short-acting albuterol MDI for that purpose.
- Anticholinergics - These are drugs that widen the bronchial tubes and reduce the amount of mucus without making it thick and difficult to bring up. They provide long-term control and are the most important medication for many men with COPD. The newer drug tiotropium (Spiriva) can be used just once a day, while ipratropium (Atrovent) requires more frequent use . Because anticholinergics and bronchodilators work in different ways, patients can benefit from using both types of drugs.
- Corticosteroids ("steroids") - These medications reduce inflammation in the bronchial tubes. Inhaled steroids can help many, but not all, patients with moderate-to-severe COPD. They are most effective for patients who are also taking long-acting bronchodilators. A combination of a steroid (fluticasone ) and a long-acting bronchodilator (salmeterol) is available for twice-a-day dry powder inhalation.
- Antibiotics - These can be critically important for flare-ups but are not helpful for maintenance therapy. Notify your doctor right away if your breathing becomes worse, if you develop a fever, or if your phlegm becomes thicker, discolored, or more plentiful.
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Does Oxygen Really Help?
People with COPD who have low blood oxygen levels can benefit greatly from long-term, round-the-clock oxygen therapy. At home, oxygen can be stored in cylinders or generated by machines called oxygen concentrators. Portable tanks can provide several hours of oxygen away from home. Oxygen therapy needs careful supervision by a physician. Because oxygen can be a fire hazard, patients and household members need to follow certain safety precautions.
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The Bottom Line
The average person will take some 600 million breaths during a lifetime. Most men can keep their lungs healthy simply by avoiding tobacco smoke and other harmful fumes. Early diagnosis and treatment can slow the damage, ward off complications, and improve the quality of life. New therapies are on the way, but simple prevention is the best treatment of all. And, after all, what's more important than preserving the breath of life?
Harvey B. Simon, M.D. is an Associate Professor of Medicine at Harvard Medical School and a member of the Health Sciences Technology Faculty at Massachusetts Institute of Technology. He is the founding editor of the Harvard Men's Health Watch newsletter and author of six consumer health books, including The Harvard Medical School Guide to Men's Health (Simon and Schuster, 2002) and The No Sweat Exercise Plan, Lose Weight, Get Healthy and Live Longer (McGraw-Hill, 2006). Dr. Simon practices at the Massachusetts General Hospital; he received the London Prize for Excellence in Teaching from Harvard and MIT.
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Hearing Loss in Adults
What Is It?
Hearing loss is a decrease in the ability to perceive sounds. It can be partial or total, sudden or gradual, temporary or permanent. It can affect one ear or both. In general, the risk of hearing loss increases with age.
Sound enters the ear and strikes the eardrum. This causes the eardrum to vibrate. The eardrum's vibrations are amplified through the middle ear by three tiny bones. Inside the ear, the vibrations are transformed into nerve impulses. These nerve impulses travel to the brain, where they are interpreted as sounds.
The outer ear and middle ear conduct sound. Any injury to this part of the hearing pathway is called conductive hearing loss. Sensorineural hearing loss is injury to the inner ear, eighth cranial nerve and brain. These structures produce, transmit and interpret nerve impulses.
Some of the most important causes of hearing loss in adults are:
- Middle ear disease. A bacterial infection of the middle ear can:
- Injure the eardrum
- Disrupt the middle-ear bones
- Cause fluid buildup
- Noise. Loud sounds can injure delicate cells within the ear. This is a form of sensorineural hearing loss. Noise-induced hearing loss can happen because of a single brief burst of an extremely loud sound. It more often results from long-term exposure to loud sounds of slightly lower intensity.
- Otosclerosis. An abnormal overgrowth of one or more bones in the middle ear prevents the small bones from moving normally. This is a type of conductive hearing loss. Otosclerosis often runs in families.
- Acoustic neuroma. This noncancerous tumor grows on part of the eighth cranial nerve. This nerve carries signals to the brain. Acoustic neuroma often causes dizziness and equilibrium problems in addition to gradual hearing loss.
- Meniere's disease. This typically causes dizziness, hearing loss, ringing in the ears (tinnitus), and a sensation of fullness or stuffiness in one or both ears. Meniere's disease occurs when excess fluid causes swelling in the inner ear.
- Trauma. Many types of accidents can cause hearing loss. Hearing loss can result when the eardrum is injured from the force of an explosion. Or it can result from a Q-tip that ruptures the eardrum during an attempt to clean the ear canal.
- Sudden sensorineural hearing loss. This is a medical emergency. A person loses hearing over a period of three days or less. In most cases, only one ear is affected. The underlying problem may be a viral infection.
- Drugs. Many prescription and nonprescription medications can damage the ear and cause hearing loss. These include:
- Anticancer chemotherapy drugs
- Antimalaria drugs
- Age. Age-related hearing loss (presbycusis) is not a single disease. Rather, it is a category for the cumulative effects of aging on the ears. Hearing loss usually begins after age 60. Both ears are affected. It is typically harder to hear high-pitched tones (women's voices, violins) than low-pitched ones (men's voices, bass guitar). Hearing loss usually occurs gradually over a period of years. The person may not realize that he or she has difficulty hearing.
- Other causes. There are more than 100 different causes of hearing loss in adults. The most common reversible causes are severe buildup of earwax in the ear canal and acute infections of the external ear or middle ear.
If you have sudden, severe hearing loss, you will notice immediately that your ability to hear has decreased dramatically or disappeared totally in the affected ear.
If your hearing loss is gradual, your symptoms may be more subtle. You may have difficulty understanding conversations. Family members may complain that you play the radio or television too loudly. You may ask them to repeat what they say or frequently misunderstand what they are saying.
Some diseases and conditions that cause hearing loss may produce additional symptoms, including:
- Ringing in the ears (tinnitus)
- Discharge or bleeding from the ear
- Deep earache, or pain in the ear canal
- Pressure or a "stuffy" feeling inside the ears
- Dizziness or problems with balance or equilibrium
Your doctor will ask you to describe your symptoms. He or she will ask if anyone in your family had or has hearing loss. Your doctor will want to know if you have been exposed to loud noises, trauma of the ear or head, or ear infections. Your doctor will want to rule out the possibility that medications may be causing your hearing loss. He or she will review the prescription and over-the-counter drugs you take.
Your doctor will examine you, and look closely at your ears. This ear exam may include:
- An examination of your ear canal and eardrum using a lighted instrument.
- The Rinne test. A vibrating tuning fork is placed on the bone behind your ear. This tests for conductive hearing loss.
- The Weber test. A vibrating tuning fork is placed in the middle of your forehead to help diagnose one-sided hearing loss.
- Audioscopy testing. The doctor uses a hand-held device to generate tones of various intensities to find out if you can hear them.
If you are diagnosed with hearing loss, your doctor will refer you to an audiologist. The audiologist will test your hearing sensitivity. He or she will check for middle-ear problems by measuring your eardrum's ability to reflect sounds. Further testing and treatment will follow.
The duration of hearing loss depends on its cause. Sensorineural hearing loss tends to be permanent.
You can help prevent hearing loss:
- Wear protective earplugs or earmuffs if you are often exposed to loud noise at work or during recreational activities.
- Never put cotton swabs or other foreign objects in your ears.
- Wear a seatbelt while driving. Wear a protective helmet while riding a bicycle.
- Know the possible side effects of your medications.
Both age-related and noise-related hearing loss tend to be permanent. Your doctor may recommend a hearing aid or an implant to improve your ability to communicate with others. A hearing aid amplifies sounds electronically and is effective for many people with age-related hearing loss. Hearing aids today are very small, so small that other people often do not notice you are wearing them. A cochlear implant translates sounds into electrical signals that can be carried to the brain.
Certain other forms of hearing loss may be treated medically or surgically:
- Otosclerosis. For mild cases, a hearing aid is usually the first option. In severe cases, one of the small bones is surgically replaced with a tiny prosthesis.
- Acoustic neuroma. Treatment includes surgery or highly focused radiation therapy.
- Meniere's disease. There is no cure. The goal of treatment is to relieve pressure in the ears to reduce symptoms. Some people improve by limiting intake of salt, caffeine or alcohol or quitting smoking. Medications to reduce fluid retention in the ear may help. In some cases, surgery may be considered.
- Traumatic hearing loss. A damaged eardrum can sometimes be repaired surgically.
- Drug-induced hearing loss. Stopping the problem medication may reverse hearing loss or prevent it from getting worse.
- Sudden sensorineural hearing loss. When the cause is unknown, this condition is usually treated with steroids.
- Other. A dense plug of earwax can be dissolved or gently removed by your doctor. Antibiotics can treat hearing loss caused by ear infections.
When To Call a Professional
Call your doctor immediately if you have sudden hearing loss. This is a medical emergency.
Also, make an appointment to see your doctor if:
- You are an older adult, and hearing loss interferes with your quality of life.
- You work in a high-noise environment, and you have trouble hearing.
- You have hearing loss together with:
- An earache
- Discharge from your ears
- Dizziness or balance problems
The prognosis is highly variable. In many cases, hearing loss cannot be treated with medications or surgery. But your quality of life may improve significantly with a hearing aid. A cochlear implant may also be an option.
National Institute on Deafness and Other Communication Disorders
National Institutes of Health
31 Center Drive, MSC 2320
Bethesda, MD 20892-2320
American Academy of Otolaryngology -- Head and Neck Surgery
1650 Diagonal Road
Alexandria, VA 22314-2857
American Speech-Language-Hearing Association (ASHA)
10801 Rockville Pike
Rockville, MD 20852
National Institute for Occupational Safety and Health
1600 Clifton Road
Atlanta, GA 30333
American Tinnitus Association
P.O. Box 5
Portland, OR 97207-0005
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The disciples of communism claim that their ideological system is the cure for colonialism and imperialism. All the proletariats (working-class people) of the world, according to the prescriptions of Marx, are brothers. However, analysts observe that communism scarcely worked that way even in theory. Marx was a German nationalist who called for the extermination of Croats, Pandurs, and “similar scum.” He sneered at Danish culture as purely copied from Germany and rejoiced at the Prussia victory over France in 1871 because it would lead to the triumph of German, rather than French, socialism. He loathed Judaism and Jewish society, as well as Christians.
The Bolshevik junta in late 1918, followed four years later by the formation of the Union of Soviet Socialist Republics (USSR), presented itself to the world as anti-colonialist and anti-imperialist.
Click here to read the entire article.
Photo: Karl Marx
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At 8:30 a.m. Pacific time today, NASA's 2001 Mars Odyssey spacecraft passed the halfway point on its journey to Mars. It has been 100 days since Odyssey's launch and 100 days remain until it arrives at the red planet.
"Odyssey is now closer to Mars than Earth. The spacecraft is healthy and all systems are looking good," said David A. Spencer, the Odyssey mission manager at NASA's Jet Propulsion Laboratory. "Planning for Mars approach and orbit insertion in October is our primary focus right now."
The navigation team reports the spacecraft is right on course. To date, the Deep Space Network has taken 11 separate measurements using the so-called delta differential one-way range measurement, a technique that uses two ground stations to determine the angular position of the spacecraft relative to the known position of a quasar. The measurements provide the navigation team with an additional source of information, adding confidence to their estimates of the Odyssey flight path.
Today, Odyssey is 45.8 million kilometers (about 28.5 million miles) from Earth and 30 million kilometers (about 19 million miles) from Mars, traveling at a velocity of 26 kilometers per second (58,000 miles per hour) relative to the Sun.
The Mars Odyssey mission is managed by JPL for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology in Pasadena. The Odyssey spacecraft was built by Lockheed Martin Astronautics, Denver.
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Making paper planes
Make a paper plane that can actually fly with these easy instructions. This traditional paper-plane design is a simple paper craft for kids that will then lead to another fun activity for kids: flying a paper aeroplane.
What you need:
- 1 x A4 sheet of paper
Fold the paper along the width and then unfold it to create a crease.
On one side of the paper, fold each corner in towards the centre, to the point where the inside edges are even with the centreline crease.
Starting at the very tip of the point, fold the paper over on each side so the inside edges line up with the centre crease.
Turn the paper airplane over and fold it in half along the centreline.
Fold the first wing with the line of the fold running nearly parallel to the centreline of the plane.
Fold the second wing the same as you did the first.
The plane is now ready to fly!
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of Florida and the Caribbean"
Bartolomé de Las Casas
Priest, missionary, landholder, fighter, writer and historian. Once a slave owner, then defender of the rights of native peoples, Bartolomé de Las Casas was a complex man who lived almost a century.
Born in 1474 in Spain, Las Casas was the son of a merchant who had traveled with Columbus to the West Indies. Following his education at the University of Salamanca, Las Casas first became a lawyer, but in 1502, at the age of 28, he gave up his law practice and sailed to Hispaniola. He worked for the colonial governor first in Santo Domingo, then in Cuba. In 1512 he became the first person in America to be ordained a priest, but that didnt stop him from taking part in the brutal conquest of Cuba. For his service in several expeditions, Las Casas was awarded an encomienda, a royal grant of land including Native American slaves.
Not long after, Las Casas began to rebel against the abusive practices of Europeans governing American lands and people. He knew firsthand the killing, capture and enslavement of native people and began a crusade to improve conditions and especially to abolish Native American slavery. He abandoned his own encomienda in 1514 and sailed back to Spain to appeal directly to King Charles V on the Native Americans behalf. He was named the official Protector of the Indians and spent the rest of his long life championing their interests.
In 1520 he tried without success to establish a colony on the coast of Venezuela. He livedfor a while in Mexico and Guatemala and in 1544 at age 70 was named Bishop of Chiapas. He returned to Spain in 1547, but continued to plead the cause of Native Americans in prolific writings. Las Casas died in 1566 at the age of 92.
Las Casas writings are significant, including the first full account of the Spanish conquest, his History of the Indies. He is most famous for his Brevísima relación de la destrucción de las Indias (Brief Account of the Destruction of the Indians) a short tract condemning the Spanish treatment of the Indians. Las Casas described atrocities committed by the conquistadors and documented the genocide that had taken place. The work was published in 1552 in Spain and quickly translated and circulated throughout Europe. It became the basis for the incriminating "Black Legend," an anti-Spanish propaganda tool that accused Spain of intolerance and persecution.
Tale of Bartolome de las Casas
Bartolome De Las
Casas, Missionary, Priest, Defender of the Oppressed
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Definition from Nolo’s Plain-English Law Dictionary
A sudden statement (also known as an "excited utterance") made by someone who has seen a surprising, startling, or shocking event (such as an accident or a death), or has suffered an injury. For example, "Oh my God, that blue car hit the little girl!" Spontaneous exclamations are often introduced at trial as evidence of the speaker's state of mind or the truth of the matter being spoken about, and will be admitted if the judge decides that the circumstances surrounding the statement make it likely that the speaker was telling the truth. Without this determination, the statement is simply hearsay; that is, a statement made out of court and offered for the truth of the matter it deals with. (See also: hearsay
Definition provided by Nolo’s Plain-English Law Dictionary.
August 19, 2010, 5:24 pm
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Expand each section to read more.
1600s Western Igbo kingdoms dominate trade in the lower Niger region.
1815 Following the end of the Napoleonic wars between France and Great Britain, Britain begins to trade with the interior, calling the region "Nigeria" based on the path the Niger River takes through the area.
1914 Igbo, Yoruba, and Hausa areas are officially united under Britain as the Colony and Protectorate of Nigeria.
1930 Chinua Achebe is born in the Igbo village of Ogidi.
1958 Things Fall Apart is published in England.
1960 Nigeria gains independence, as a parliamentary democracy.
This story of the Igbos around 1900 was written by one of their grandchildren; Chinua Achebe was born in 1930 in southeastern Nigeria, in the Igbo village of Ogidi. He grew up speaking English and reading English literature, but Achebe kept a deep attachment to his Igbo roots; eventually he came to question the English literary portrayal of Africa and Africans as violent, ignorant, and primitive. Achebe wanted to give Africans their own voice, to take control of how they were seen, and to repair their own self-image.
The result was Things Fall Apart. The hero of the story is Okonkwo, a self-made man who has been unstoppable in his determination to rise in his society, the village of Umuofia. His greatest fear is being weak, like his father, whom he detested. Okonkwo will go to any lengths to prove to the world and to himself that he is strong and fearless—even to the point of destroying himself.
Umuofia is not a paradise or a hell. Its people are not evil and ignorant, nor are they innocent, noble savages. These European points of view are discarded. Umuofia is filled with real people who have complex personalities. When the British missionaries arrive in Umuofia, it is shocking to realize that most of them would destroy Igbo culture without a second thought.
But Achebe's refusal to paint the conflict in black and white is what makes Things Fall Apart so powerful. Just as Umuofia was not perfect, the British are not all evil. The missionaries offer acceptance, love, and respect to those Igbos who have been outcast by their village for religious reasons. If only the two groups could have met in a spirit of compromise, they might have been able to live peacefully together. But the British insistence on domination, and the Igbo fear and rejection of their people who convert to Christianity, spell doom for Umuofia. Each side fears the other, and, like Okonkwo, each side is so fearful of appearing weak that it will resort to violence to keep the upper hand. Achebe shows that the coming of Europeans to Africa was not light coming to darkness, or pure evil destroying a people; it was two imperfect societies set on a collision course from which neither could emerge whole again.
Achebe wrote Things Fall Apart in English. The decision was controversial amongst African writers at the time, some of whom wanted to promote native African languages, while others accepted English. If Achebe wrote in English, he was using the language of the colonizer, a non-African voice, to tell an African story, once again. But if he wrote in Igbo, he was limiting the potential audience for the novel to a single group of people in Nigeria.
In an essay called "The African Writer and the English Language," Achebe describes the problem:
For an African writing in English is not without its serious setbacks. He often finds himself describing situations or modes of thought which have no direct equivalent in the English way of life. Caught in that situation he can do one of two things. He can try and contain what he wants to say within the limits of conventional English or he can try to push back those limits to accommodate his ideas... I submit that those who can do the work of extending the frontiers of English so as to accommodate African thought-patterns must do it through their mastery of English and not out of innocence.
In other words, African writers can use English to change it, and turn it into a language of African experience and not just English experience.
Achebe changed English by infusing it with Igbo syntax, usage, and vocabulary so that while Things Fall Apart is clearly written in English, it is a new kind of English that serves an Igbo purpose.
- Mr. Brown
- The first white missionary to arrive in Umuofia, Mr. Brown is respectful and patient, never attacking clan customs or religion directly. His early success is endangered by his ill health.
- The District Commissioner
- The highest English official in the region arrives with the missionaries and oversees the fall of the villages from a distance.
- Okonkwo's second wife, who left her first husband for Okonkwo. She has borne ten children and lost all but one, her daughter Ezinma. Her love for Ezinma leads her to stand up to Okonkwo on occasion.
- She is Okonkwo's favorite child, beautiful and connected to her father in a deep way. Only she can understand him and his moods. Her only flaw, in his eyes, is being a girl.
- A boy from a neighboring clan who is seized by Umuofia warriors. He lives with Okonkwo's family as a peace offering, and is a more satisfying son to Okonkwo than Nwoye.
- This self-made man has worked his way up from poverty and, as he sees it, freed himself from the disgrace of having a lazy, "feminine" father. While Okonkwo possesses real virtues of hard work, far-sightedness, devotion to his clan, and love, these co-exist uneasily with impulses of fear, pride, and impatience.
- Okonkwo's eldest son shows every sign―so far as Okonkwo is concerned―of being a lazy, weak man like Unoka. Beaten and belittled by his father, Nwoye will become a prime target for conversion by the English missionaries.
- Nwoye's mother
- Okonkwo's first wife, whose name is not told to the reader. She, unlike her husband, understands the value of pity, gentleness, and forgiveness. Her stories instruct and delight the children.
- A thoughtful member of the clan who is Okonkwo's best friend. He tries to help Okonkwo navigate the troubles that come to him, and is left cleaning up after Okonkwo's catastrophic end.
- Ogbuefi Ezeudu
- The highest-ranking man in the village, and holder of three titles―a great rarity.
- Mr. Smith
- The far more zealous Smith replaces Brown and leads his new converts on a full-scale war of ideas against the village.
- Okonkwo's father, a gentle musician who left his family poor and in debt at his death. He held no titles of rank in the village―driving Okonkwo to vow that he would hold many.
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Guide to writing history papers
Reading, Writing, and Researching for History: A Guide for College Students
A comprehensive but easy-to-skim web guide to writing history papers. Recommended by History Dept faculty.
Using call numbers to find books
Books and journals are arranged on our shelves according to the Library of Congress (LC) classification system. Each is assigned a unique call number based on its subject matter and other characteristics. Items on the same subject will often be grouped together.
In using a call number to locate a book on the shelf, consider each element in turn before moving on to the next segment.
These call numbers are arranged as they should appear on the shelves. In each case, the element shown in boldface distinguishes the number from the preceding one:
Each call number consists of several elements. For example::
The FIRST line, TK, is based on the broad subject of the book. Within Class T for technology, TK represents electrical engineering.
The SECOND line, 7881.6, defines the subject matter more finely. When looking for the book, read this as a whole number with a decimal component. In this example, TK7881.6 represents magnetic recording (a subdivision of TK— electrical engineering).
The THIRD line, M29, usually indicates author, but may also represent a further subject subdivision, geographic area, etc. There may also be a fourth line, formatted the same way. When looking for the book, read the numeric component as if it were preceded by a decimal point. In the example above, the numeric part of M29 should be read as ".29" (and the call number TK7881.6 M29 comes before TK7881.6 M4).
The YEAR of publication, such as 1993, may also be present. These file in chronological order and often indicate successive editions of a book. The call number may also have additional elements, such as volume numbers.
To use library databases from off campus you have to set up the proxy server: this changes your browser settings.
Where's the PDF?
Many article databases contain information about articles (citations or abstracts), not the entire text of the article. Once you've used an article database to find articles on your topic, you may need to use this button: in order to locate and read the full text of the article. The UC-eLinks button appears in nearly all the databases available from the UCB Library website.
UC-eLinks will link you to the online full text of an article if UCB has paid for online access; otherwise, UC-eLinks will help you locate a print copy on the shelf in the library. If UCB doesn't own the article in print or online format, UC-eLinks can also help you order a copy from another library.
For more information, watch this video tutorial (about 4 min.)
You can also set up UC-eLinks to work with Google Scholar. For more information, watch this video tutorial (about 2 min.)
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What is pathology?
Pathology, or general pathology, is the medical specialty focused on the diagnosis of disease through analysis of blood, tissues or urine in a pathology lab. A division of pathology is anatomical pathology (study of organs and tissues to diagnose disease), which is broken into the following subspecialties: forensic pathology (determining cause of death), autopsy pathology (performing autopsies), surgical pathology, and cytopathology (study of diseases on the cellular level). Other subspecialties include clinical chemical pathology (study of antibodies, hormones, immune system and pharmacology), clinical pathology (working directly with patients), hematology (study of blood) and microbiology (study of bacteria, parasites and viruses).
Who are pathologists?
Pathologists are doctors who are concerned with the diagnosis of disease, as well as prevention and treatment. These specialists use a microscope or other diagnostic tools to look at blood, urine or other body fluid specimens and detect chemical makeup in the body. Based on the test results, he or she may recommend additional study of the specimen.
Pathologists typically work in a hospital or pathology lab, and may work in administrative roles supervising divisions of a clinical pathology lab. They may oversee special divisions of the lab, such as the blood bank, clinical chemistry, hematology, immunology and serology, and microbiology. Pathologists are certified by The American Board of Pathology.What types of specimens does a pathologist collect?
General pathology relates to the collection of a specimen or specimens for the diagnosis of disease. The types of specimens a pathologist may collect include:
Related Articles:Do It Yourself Lab Tests New Sensor Could Replace Finger-Prick Testing
- Blood – Usually drawn from a vein through a needle in the forearm, or sometimes pricked from a finger.
- Urine – The “random method” is when a patient urinates into a cup; “clean catch specimen” takes a sample of urine after the outer genital area has been sanitized; and a “sterile urine test” requires catheterization (a tube inserted through the urethra into the bladder to take a sample of urine). Sometimes the patient will need to undergo several urine tests to measure changes in urine over time.
- Sputum (phlegm) – Samples are taken from sputum that has been coughed into a clean container.
- Feces – Collected by the patient into a clean plastic or cardboard container.
- Other bodily fluids– Spinal fluid, pleural fluids (lung or pleural cavity fluids), abdominal fluids, joint fluids.
- Tissue – Obtained from any organ in the body such as liver, bone, brain, skin, intestines, etc.
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The term Unix-like is widely used to describe operating systems that share many of the characteristics of the original UNIX, which was written in 1969 by Ken Thompson at Bell Labs, and its early successors.
The popularity of this term is mainly due to the fact that it is a very convenient and logical way of describing the numerous and diverse operating systems that fit into this category. It is also due in part to the controversy about what really is UNIX and how this term should be used. This controversy, in turn, has arisen largely as a result of the complex history of UNIX and the operating systems that have been based on it.
The category of Unix-like operating systems clearly includes those systems that have all three of the following characteristics: a direct source code lineage from the original UNIX, obvious UNIX characteristics and officially describe themselves as being UNIX. Source code is the version of software as it is originally written (i.e., typed into a computer) by a human in plain text (i.e., human readable alphanumeric characters). Such systems include AIX (developed by IBM), HP-UX (developed by HP), IRIX (developed by Silicon Graphics), Solaris (developed by Sun Microsystems) and True64 (developed by Compaq for alpha processors and now owned by HP).
The category of Unix-like operating systems also includes UNIX clones. A clone is a program (i.e., an operating system or an application program) that has functions and behavior similar to another program but which does not contain source code from that program.
The functions and behavior of the UNIX clones are so similar to those of the early (and later) versions of UNIX, in fact, that many knowledgeable users consider them to be UNIX. However, they do not have a direct lineage to the original UNIX source code, and most of them do not officially describe themselves as being UNIX. This category includes the BSDs (i.e., FreeBSD, NetBSD, OpenBSD and Darwin), Linux, MINIX, QNX and Cygwin.
Unix-like operating systems also generally contain most or all of the enhancements and new features that were subsequently added at the University of California at Berkeley (UCB) and which are known as the Berkeley extensions. The Berkeley extensions include such now nearly universal innovations as the C shell, also referred to as csh, TCP/IP (transmission control protocol/Internet protocol), which forms the basis for both the Internet and most local networks, virtual memory, which allows a hard disk drive (HDD) to simulate additional main memory, and the vi text editor. Thus, it has been suggested that operating systems that refer to themselves as UNIX might more appropriately call themselves something such as UNIX/Berkeley.
BSD (Berkeley Software Distribution), the version of UNIX developed at UCB in the 1970s and early 1980s, was widely considered to be a type of UNIX, as are its modern day descendants. In fact, BSD even included UNIX in its name, such as BSD UNIX 4.0, which was released in October 1980.
The original name for the operating system developed at Bell Labs was UNIX (all upper case). This term became a trademark that was eventually acquired by The Open Group, an industry consortium that was formed in 1996. The Open Group attempts to permit operating systems to call themselves UNIX only if they both conform to its Single UNIX Specification and pay a substantial fee (which is one of its main sources of revenue). Thus, at least theoretically, an operating system would not have to contain any of the original UNIX source code or bear much superficial resemblance to the original UNIX to be permitted to call itself UNIX.
Adding to the complexity of the situation is the fact that there is some controversy as to whether the term UNIX is actually a valid trademark. This is because trademark law states that when a term becomes very widely used as a generic term (i.e., a term that describes a class of products rather than just a single brand) it can lose its legally protected trademark status.
Apple Computer, which uses Darwin (a Unix-like operating system based on BSD) as the core of its increasingly popular Mac OS X operating system, claims that the term UNIX has become generic and thus that it is not a legally valid trademark. Apple has vastly greater legal and financial resources than the BSDs or most of the Linux distributions (i.e., versions), and thus it is not afraid to call its operating system UNIX. In fact, it makes a number of statements on its website explicitly referring to itself as UNIX (and not as Unix-like), including the following: "Don't let its elegant and easy-to-use interface fool you. Beneath the surface of Mac OS X lies an industrial-strength UNIX foundation hard at work to ensure that your computing experience remains free of system crashes and compromised performance."
As a result, the Open Group is suing Apple Computer for alleged trademark violation. This is a necessary move for the Open Group, as attempting to protect a trademark from abuse can be an important factor in legal decisions about the validity of the trademark. However, some industry observers expect that this case will be settled quietly out of court because neither side wants to risk a negative judgment1.
The BSD operating systems are widely regarded as free (both in a monetary sense and with regard to use) implementations of UNIX, and thus as UNIX. However, in contrast to Apple, they make a point of not referring to themselves as being UNIX on their websites or other materials in order to avoid potentially costly legal problems. For example, FreeBSD, the most popular of the BSD systems (at least until the recent rise of Darwin), describes itself as being " . . . a very economical alternative to commercial UNIX® workstations." NetBSD describes itself on its homepage as " . . . a free, secure, and highly portable Unix-like Open Source operating system available for many platforms, . . . " OpenBSD describes itself as " . . . a FREE, multi-platform 4.4BSD-based UNIX-like operating system."
Some operating systems do not seek UNIX branding because the royalties would be prohibitively expensive for them due to the facts that they are updated frequently (which would require costly recertification) and that they are made available freely over the Internet. Moreover, developers of such systems generally feel that such branding would not provide any significant advantage, as their users are generally well informed and are interested in the intrinsic values of the systems rather than in their names.
The term Unix-like does not have any negative implication about the validity of the UNIX trademark. In fact, it could even be argued that it supports the trademark by providing a convenient term for describing operating systems that resemble the original UNIX and its early successors so that they, and their users, will not be tempted to inappropriately use the term UNIX.
Other terminology is also sometimes used to refer to Unix-like operating systems, particularly UN*X, Un*x, *NIX and *nix.
Created April 19, 2005. Updated June 18, 2006.
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Papal Primer: History's 10 Most Intriguing Popes
Pope Benedict XVI announced his resignation in February, citing his deteriorating mental and physical health
CREDIT: Jeffrey Bruno | Shutterstock.com
Pope Benedict XVI made headlines today (Feb. 11) when he announced he was stepping down — something no pope has done since the Middle Ages. While that's big news, the Catholic Church has seen much more dramatic upheavals.
From a cadaver on trial to a three-timing pope, here are 10 of the most interesting church fathers in history.
The first head of the Catholic Church was St. Peter. Peter, whose original name was Simon, was one of Jesus' 12 apostles, according to John Julius Norwich in his book "Absolute Monarchs: A History of the Papacy" (Random House, 2012). He preached throughout Asia Minor before coming to Rome, where he lived for 25 years, when Emperor Nero Augustus Caesar crucified him. Legend has it that he sought to be crucified upside down, deeming himself too low to share in the same death as Jesus. Though now considered the first pope, he never officially took that title during his lifetime. [Photos: Gladiators of the Roman Empire]
The first pope to step down was Pontian, who headed the church from A.D. 230 to 235. Unlike many of his predecessors, Pontian wasn't martyred, but rather was sentenced to hard labor in the Sardinian mineral mines by Emperor Maximus the Thracian who was persecuting Christians, particularly heads of church. The pope voluntarily abdicated to prevent the church from having a power vacuum, according to the Catholic Encyclopedia.
The next hundred years was rough for the Catholic Church, with persecution of Christians and martyrdom for several of the church heads. But in A.D. 313, Emperor Constantine officially put an end to Christian persecution. Pope Sylvester I was the first pope to live in this less dangerous world, but when Constantine arranged the Council of Nicea to sort out official Christian doctrine, Sylvester chose to sit it out, sending underlings instead, according to "Absolute Monarchs: A History of the Papacy." The Nicene Creed is now considered the first official statement of belief for Christians.
Pope Leo I, who reigned from A.D. 461 to 468, may have been most famous for work he did before ascending to the papacy: The former aristocrat and then bishop convinced the feared Attila the Hun not to sack Rome. It's possible Leo offered Attila a pile of loot, or the warlord used the meeting as an excuse to turn back, given his own strategic concerns.
Another possibility is that the pope may have played on Attila's superstitious fear of dying soon after the sacking, just as Alaric I (king of a tribe of Goths) did after the despoiling of Rome decades earlier, according to "Absolute Monarchs: A History of the Papacy." [Saint or Spiritual Slacker? Test Your Religious Knowledge]
Cadaver on trial
Pope Formosus headed the Catholic Church from A.D. 891 to 896, and his reign was marked by political battles and infighting. He was excommunicated about 20 years prior to his reign, but then later absolved. After his death, his cadaver was exhumed, put on trial, and judged to be unworthy of the papacy. All of his papal edicts were deemed invalid, the fingers he used to make sacraments were ripped off, and he was tossed into the Tiber River.
The current pope isn't the only Benedict to have stepped down. During a tumultuous time in the Catholic Church's history known as the saeculum obscurum (sometimes called the Rule of the Harlots), the popes engaged in corrupt venal behavior and were too closely allied to one aristocratic family. Fed up, the people in Rome raised Benedict V to the highest position in A.D. 964. But the founder of the Holy Roman Empire, King Otto, wasn't having it: He elected an antipope, Leo VIII, instead. Benedict V chose to step down a few months after being elected. (At this chaotic time, it wasn't unheard of to have two popes elected.)
The next Benedict, Benedict VI, also faced an ignominious end to his reign: When King Otto died in 974, Benedict VI was imprisoned and put to death by his antipope successor.
Another Benedict, Pope Benedict IX, had three runs at the papacy. The ne'er-do-well ascended to the highest office in 1032 as a result of family connections at the tender age of 20, according to the Catholic Encyclopedia. The ruler reportedly lacked all moral balance and led a dissolute life. In 1044, the city of Rome elected an antipope (a second pope). Benedict IX drove out the antipope, but then stepped down — only after selling the papacy to yet another priest. Before he died, he seized the highest office one more time, but Benedict IX's final stint was short lived.
One legend has it that from A.D. 855 to 877, a Pope John who reigned may have actually been a woman. The story, recounted by a Dominican monk named Martin in 1265 and several others, claims that Pope John was a girl who was brought to Athens in men's clothing, according to "Absolute Monarchs: A History of the Papacy." She took up study and became a master of learning, the story goes, but became pregnant and gave birth in a church procession. However, the chaos at the time and the discrepancies between different stories suggests this "Pope Joan" may never have existed.
Many of the men who have been chosen for the highest office didn't get a chance to do much with it. Pope-elect Stephen was elected in A.D. 752, but died just a few days later, without being consecrated into office. Pope Damasus II ascended to the papacy in 1048, after several political squabbles, but passed away just 23 days later. Celestine IV, who was elected in 1241, died just 16 days later — too early for his coronation. And Pope Urban VII, at 12 days in A.D. 1590, was the shortest-reigning pope in the Catholic Church's history.
The Catholic Church has also had several periods where no pope reigned. These gaps, known as interregnums, usually occurred when the cardinals who vote for the pope were deadlocked.
The last pope to abdicate, Pope Gregory XII, was elected in 1406, more than 600 years ago. A man noted for his piety, he was originally elected to end the schism that occurred after Pope Innocent VII died, according to the Catholic Encyclopedia. Gregory XII was one of three popes to rule at the time, and the ensuing chaos must have convinced him it was time to quit. He eventually convened a council to sort out the mess, and abdicated in 1415.
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Earth from Space: Easter Island
Easter Island as seen by astronauts aboard the International Space Station on Sept. 25, 2002.
On Easter Sunday in 1722, Dutch explorer Jacob Roggeveen became the first known European to encounter this Polynesian island and gave it the name it has become most widely known by.
Easter Island (also known as Rapa Nui in the native language) is one of the most isolated spots on Earth, lying some 2,000 miles from the nearest areas of human habitation (Tahiti and Chile) — even more remote than the astronauts orbiting at 210 nautical miles above the Earth.. The island, which is only 15 miles long, was annexed by Chile in 1888. (In Spanish, it is called "Isla de Pascua," which means "Easter Island.")
Archaeological evidence suggests that Polynesians from other Pacific Islands discovered and colonized Easter Island around the year 400.
The island and its early inhabitants are best known for the giant stone monoliths, known as Moai, placed along the coastline.
It is thought that the population grew bigger than was sustainable on the small island, resulting in civil war, deforestation and near collapse of the island ecosystem . Today, a new forest (primarily eucalyptus) has been established in the center of the island (the dark green in the image), according to a NASA statement.
Volcanic landforms dominate the geography of the island, including the large crater Rana Kao at the southwest end of the island and a line of cinder cones that stretch north from the central mountain. Near Rana Kao is the longest runway in Chile, which served as an emergency landing spot for the space shuttle before its retirement in 2011.
MORE FROM LiveScience.com
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High blood pressure, or hypertension, affects almost one in three adults in the United States. However, this serious health condition isn't limited to just those ages 18 and older.
The number of children and adolescents with high blood pressure is increasing. This rise can be partly blamed on the increasing number of overweight and obese children.
High blood pressure is a major risk factor for heart disease and is the primary risk factor for stroke. Prehypertension is a condition that increases a child's risk of developing high blood pressure in the future. Children with hypertension have a higher risk for high blood pressure as adults. High blood pressure in childhood is also correlated with early development of atherosclerosis in adulthood.
Systolic pressure is the top number in a blood pressure reading and corresponds to the pressure in arteries when the heart contracts. Diastolic pressure is the bottom number in a blood pressure reading, and corresponds to the pressure in the arteries between heart beats, when the heart relaxes.
The American Academy of Pediatrics recommends that children ages 3 years and older have their blood pressure measured each time they see their health care provider for routine checkups. Normal blood pressure in children depends on their gender, age, and height.
Parents and health care providers encourage children with high blood pressure to make lifestyle changes, such as losing weight. Other changes may include increased exercise and improved diet. A doctor may also give a child prescription medication to help control blood pressure.
Regular exercise helps control weight and may keep blood pressure in check. Regular exercise means 30 to 60 minutes of moderate physical activity on most days. Sedentary activities should be limited to less than two hours a day.
A healthy diet for a child with prehypertension or high blood pressure includes fresh vegetables and fruits, additional fiber, and nonfat dairy products, as well as limited salt and sodium. The American Heart Association recommends a maximum daily sodium intake of 1,500 mg/day; however, this number may be lower, depending on your child's age and other health considerations. Please consult your child's pediatrician regarding the recommended sodium intake for your child.
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South Korea (officially, Republic of Korea) encompasses an area of 98,477 sq. km. (38,022 sq. mi.), about the size of state of Indiana. Its capital is Seoul (population 10.3 million); other major cities are: Busan, Daegu, Inchon, Gwangju, Daejeon, and Ulsan. The terrain of South Korea consists of forested mountain ranges separated by deep, narrow valleys and cultivated plains along the coasts. South Korea is bordered by North Korea to the North and is surrounded by the Sea of Japan, Korean Strait, and Yellow Sea.
An independent Korean state or a collection of states has existed almost continuously for several millennia. Between its initial unification in the 7th century, until the 20th century, Korea existed as a single independent country. In 1905, following the Russo-Japanese War, Korea became a protectorate of imperial Japan, and in 1910 it was annexed as a colony. Korea regained its independence following Japan's surrender to the United States in 1945. After World War II, the Republic of Korea (ROK) was set up in the southern half of the Korean Peninsula. During the Korean War (1950-53), US troops and UN forces fought alongside soldiers from the ROK to defend South Korea from Democratic People's Republic of Korea attacks supported by China and the Soviet Union. An armistice was signed in 1953, splitting the peninsula along a demilitarized zone at about the 38th parallel.
After 1953, South Korea achieved rapid economic growth. In 1993, Kim Young-sam became South Korea's first civilian president, following 32 years of military rule. In June 2000, a historic North-South summit took place between South's President Kim Dae-jung and the North's leader Kim Jong Il.
The natural hazards facing South Korea consist of occasional typhoons bringing high winds and floods and low-level seismic activity. In 2004, South Korea's oil consumption was 2.149 barrels per day (bbl/day); its exports were 644,100 bbl/day and imports were 2.83 million bbl/day.
U.S. State Department Background Notes; CIA World Factbook, 2007/9; 2007/12
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Historical diversification of migration patterns in a passerine bird
Förlag: Society for the Study of Evolution
Migratory strategies of birds require complex orientation mechanisms, morphological adaptations, and life-history adjustments. From an evolutionary perspective, it is important to know how fast this complex combination of traits can evolve. We analyzed mitochondrial control-region DNA sequences in 241 blackcaps (Sylvia atricapilla) from 12 populations with different migratory behaviors. The sample included sedentary populations in Europe and Atlantic archipelagos and migratory populations with different distances of migration, from regional to intercontinental migrations, and different heading directions (due to a migratory divide in central Europe). There was no genetic structure between migratory and sedentary populations, or among populations from different biogeographic areas (Atlantic islands, the Iberian Peninsula, or the continent), however we found evidence of a genetic structure when comparing populations located on either side of the migratory divide. These findings support an independent evolution of highly divergent migratory strategies in blackcaps, occurring after a postglacial colonization of the continent along western and eastern routes. Accordingly, mismatch-distribution analyses suggested an expansion of blackcaps from a very small population size, and time estimates dated such an expansion during the last postglacial period. However, the populations in Gibraltar, located in a putative Mediterranean refuge, appeared to be independent of these processes, showing evidence of restricted gene flow with other populations and demonstrating insignificant historical changes in effective population size. Our results show that the interruption of gene flow between migratory and sedentary populations is not necessary for the maintenance of such a polymorphism, and that even the most divergent migratory strategies of a bird species are susceptible to evolution in response to historical environmental changes.
- Biology and Life Sciences
- Molecular Ecology and Evolution Lab
- ISSN: 0014-3820
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Talking About Economic Troubles
Download MP3 (Right-click or option-click the link.)
I'm Susan Clark with the Special English program WORDS AND THEIR STORIES.
In the nineteen thirties, a song, "Brother, Can You Spare a Dime?," was very popular in the United States. It was the time of the big Depression. The song had meaning for many people who had lost their jobs.
A dime is a piece of money whose value is one-tenth of a dollar. Today, a dime does not buy much. But it was different in the nineteen thirties. A dime sometimes meant the difference between eating and starving.
The American economy today is much better. Yet, many workers are concerned about losing their jobs as companies re-organize.
Americans have special ways of talking about economic troubles. People in businesses may say they feel the pinch. Or they may say they are up against it. Or, if things are really bad, they may say they have to throw in the towel.
A pinch is painful pressure. To feel the pinch is to suffer painful pressure involving money.
The expression, feel the pinch, has been used since the sixteenth century. The famous English writer William Shakespeare wrote something very close to this in his great play "King Lear."
King Lear says he would accept necessity's sharp pinch. He means he would have to do without many of the things he always had.
Much later, the Times of London newspaper used the expression about bad economic times during the eighteen sixties. It said, "so much money having been spent ... All classes felt the pinch."
Worse than feeling the pinch is being up against it. The saying means to be in a lot of trouble.
Word expert James Rogers says the word "it" in the saying can mean any and all difficulties. He says the saying became popular in the United States and Canada in the late nineteenth century. Writer George Ade used it in a book called "Artie." He wrote, "I saw I was up against it."
Sometimes a business that is up against it will have to throw in the towel. This means to accept defeat or surrender.
Throwing in the towel may mean that a company will have to declare bankruptcy. The company will have to take legal steps to let people know it has no money to pay its debts.
Word expert Charles Funk says an eighteen seventy-four publication called the Slang Dictionary explains throwing in the towel. It says the words probably come from the sport of boxing, or prizefighting. The book says the saying began because a competitor's face was cleaned with a cloth towel or other material. When a boxer's towel was thrown, it meant he was admitting defeat.
Most businesses do not throw in the towel. They just re-organize so they can compete better.
This WORDS AND THEIR STORIES was written by Jeri Watson. I'm Susan Clark.
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Frilled Sharks, Chlamydoselachus anguineus
Taxonomy Animalia Chordata Elasmobranchii Hexanchiformes Chlamydoselachidae Chlamydoselachus anguineus
Description & Behavior
Frilled sharks, Chlamydoselachus anguineus (Garman, 1884), aka frill sharks, frill-gilled sharks, Greenland sharks, scaffold sharks, and silk sharks are members of the most ancient frill and cow sharks order, Hexanchiformes. Hexanchiform sharks have a single dorsal fin, either six or seven gill slits (versus the 5 found in all other existing sharks), and no nictitating membranes (protective third eyelids). The frilled shark, Chlamydoselachus anguineus, is currently one of only two known species of frilled sharks. The southern African frill shark, C. africana, was recently discovered (2009) off southern Angola, Namibia and South Africa. They are both very different in other ways from the cow sharks and are likely to be moved to their own order Chlamydoselachiformes in the near future.
Frilled sharks, Chlamydoselachus anguineus, are deepwater eel-like sharks that reach lengths up to 2 m and are thought to reach sexual maturity when they are 1.35 to 1.5 m long. They are dark brown or gray in color above, sometimes lighter below, and have six pairs of "frilly" gill slits where the first gill slit is joined under their jaws forming a sort of collar. Frilled sharks' heads are broad and flattened with short, rounded snouts. Their nostrils are vertical slits, separated into incurrent and excurrent openings by a leading flap of skin. The moderately large eyes are horizontally oval (like a cat's).
Their mouth is located at the leading edge of their snout (terminal) rather than underneath like most sharks and they have small tricuspid teeth in both jaws. Their rows of teeth are rather widely spaced, numbering 19–28 teeth in their upper jaws and 21–29 teeth in their lower jaws. Each tooth is small, with three slender, needle-like cusps alternating with two cusplets. Their very long jaws are positioned terminally (at the end of the snout), as opposed to the underslung jaws of most sharks.
They have a small lobe-like dorsal fin set far back over their pelvic fins with an anal fin that is larger than their dorsal fin. Their pectoral fins are small and paddle-shaped and their very long caudal fin (tail fin) has a small ventral lobe and without a subterminal notch.
Frilled sharks also have a pair of thick skin folds of unknown function (possibly to help allow for expansion when digesting larger prey) running along their bellies, separated by a groove, and their midsections are relatively longer in females than in males.
Frilled shark differs from their southern African relative, C. africana, by having more vertebrae (160–171 vs 147) and more turns in the spiral valve intestine (35–49 versus 26–28), as well as differences in various proportional measurements such as a longer head and shorter gill slits. The maximum known length is 1.7 m for males and 2.0 m for females.
Frilled sharks are highly specialized for life in the deep sea with reduced, poorly-calcified skeletons and enormous livers filled with low-density lipids, which allows them to maintain their position in water with little effort. They are also one of the few sharks with an "open" lateral line, in which the mechanoreceptive hair cells are positioned in grooves that are directly exposed to the surrounding seawater. This configuration is thought to be the most primitive in sharks and may enhance their sensitivity to minute movements of prey in their proximity.
Many frilled sharks are found with the tips of their tails missing, probably from predatory attacks by other shark species.
These sharks, or a proposed giant relative, have been suggested as a source for reports of sea serpents.
World Range & Habitat
Frilled sharks, Chlamydoselachus anguineus, are an uncommon "primitive" shark species typically found near the sea floor in waters over outer continental and island (insular) shelves and upper slopes, usually at depths between 120 and 1,280 m but up to 1,570 m and occasionally even at the surface.
Frilled sharks are thought to have a wide though patchy distribution (74°N - 58°S, 169°W - 180°E) in the Atlantic and Pacific Oceans. In Suruga Bay, Japan they are most common at depths between 50 m and 200 m.
In the western Indian Ocean they are found off South Africa as C. africana. In the western Pacific, frilled sharks are known to live off Japan and south to New Zealand, New South Wales and Tasmania in Australia. In the eastern/central Pacific they have been observed off Hawaii, southern California to northern Chile. Frilled sharks have also been observed in the eastern Atlantic from waters off northern Norway to northern Namibia, and possibly off the eastern Cape of Good Hope in South Africa.
In the central Atlantic, they have been caught at several locations along the Mid-Atlantic Ridge, from north of the Azores to the Rio Grande Rise off southern Brazil, as well as over the Vavilov Ridge off West Africa. In the western Atlantic, it has been reported from off New England, Georgia, and Suriname.
Feeding Behavior (Ecology)
Frilled sharks, Chlamydoselachus anguineus, feed on cephalopods (mainly squid), other sharks, and bony fishes. Feeding behavior has not yet been observed by this weak-swimming species, though they are thought to capture active, fast-moving squid by taking advantage of injured squid or those that are exhausted and dying after spawning. Alternatively, they may surprise their prey by curving their body like a spring, bracing themselves with rear positioned fins, and launching quick strikes forward like a snake. They may also be able to close their gill slits creating negative internal pressure to suck prey quickly into their mouth. They have many small, sharp, rear-pointing (recurved) teeth that function much like squid jigs which could easily snag the body or tentacles of a squid, particularly as they are rotated outwards when their jaws are protruded. Observations of captive frilled sharks swimming with their mouths open might also suggest that the small teeth, light against their dark mouths, may even fool squid into attacking and entangling themselves.
Using their long, extremely flexible jaws they should be able to swallow large prey (up to half its size!) whole, while their many rows of needle-like teeth would make escape essentially futile. Examining the length and articulation of their jaws appears to show that frilled sharks cannot deliver as strong a bite as more conventionally built sharks. Most captured individuals have been found with no or barely identifiable stomach contents, suggesting that they have a fast digestion rate and/or long intervals between feedings. One 1.6 m long individual, caught off Japan, was found to have swallowed an entire 590 g Japanese catshark, Apristurus japonicus. Squid comprise some 60% of the diet of these sharks in Suruga Bay and this includes not only slow-moving, deep-dwelling squid such as Chiroteuthis and Histioteuthis, but also relatively large, powerful swimmers of the open ocean such as Onychoteuthis, Sthenoteuthis, and Todarodes.
Frilled sharks, Chlamydoselachus anguineus, are aplacental viviparous (aka ovoviviparity) where the embryos emerge from their egg capsules inside their mother's uterus and are nourished by their yolk until birth. Frilled sharks' gestation period may be as long as three and a half years, the longest of any vertebrate. Between 2 and 15 young are born at a time (average is 6) measuring 40–60 cm long, and there appears to be no distinct breeding season (which is expected as these sharks inhabits depths at which there is little to no seasonal influence). Male frill sharks attain sexual maturity at 1.0–1.2 m long and females at 1.3–1.5 m. A possible mating aggregation of 15 male and 19 female frilled sharks was recorded over a seamount on the Mid-Atlantic Ridge.
Conservation Status & Comments
Frilled sharks, Chlamydoselachus anguineus, are listed as Near Threatened (NT) by the IUCN Red List: "A generally rare to uncommon deepwater species, with a few localities where it is taken more commonly as bycatch in several fisheries. Not an important target species, but a regular though small bycatch in many bottom trawl, midwater trawl, deep-set longline, and deep-set gillnet fisheries. As bycatch, this species is variously either used for meat, fishmeal, or discarded. Occasionally kept in aquaria (Japan). There is some concern that expansion of deepwater fisheries effort (geographically and in depth range) will increase the levels of bycatch. Although little is known of its life history, this deepwater species is likely to have very little resilience to depletion as a result of even non-targeted exploitation. It is classified as Near Threatened due to concern that it may meet the Vulnerable A2d+A3d+4d criteria."
On August 27, 2004, the first observation of this species in its natural habitat was made by the ROV Johnson-Sea-Link II, on the Blake Plateau off the southeastern United States (see the first photo above). On January 21, 2007, a Japanese fisherman discovered a 1.6 m long female alive at the surface, perhaps there because of illness or weakness from the warm water. It was brought to Awashima Marine Park in Shizuoka, where it died after a few hours (see the video above). Garman, and numerous authors since, have advanced the frilled shark as an explanation for sea serpent sightings. Because of the shark's modest size, some cryptozoologists have posited the existence of a giant relative, particularly as larger Chlamydoselachus species are known from the fossil record.
References & Further Research
Research Chlamydoselachus anguineus » Barcode of Life ~ BioOne ~ Biodiversity Heritage Library ~ CITES ~ Cornell Macaulay Library [audio / video] ~ Encyclopedia of Life (EOL) ~ ESA Online Journals ~ FishBase ~ Florida Museum of Natural History Ichthyology Department ~ GBIF ~ Google Scholar ~ ITIS ~ IUCN RedList (Threatened Status) ~ Marine Species Identification Portal ~ NCBI (PubMed, GenBank, etc.) ~ Ocean Biogeographic Information System ~ PLOS ~ SCIRIS ~ SIRIS ~ Tree of Life Web Project ~ UNEP-WCMC Species Database ~ WoRMS
Feedback & Citation
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Ancient secrets of Merlin’s Barrow unearthed
The Wiltshire landscape around Avebury and Silbury Hill is at the heart of prehistoric Britain, and has World Heritage designation. Now another monument can be added to its archaeological treasures: the Marlborough Mound.
The Mound lies in the heart of the grounds of Marlborough College, and has been interwoven with local folklore for hundreds of years. The town’s motto, Ubi nunc sapientis ossa Merlini (‘Where now are the bones of wise Merlin?’), echoes the myth which convinced generations that Merlin’s bones were buried under the Mound. These were the seductive Arthurian legends that may have drawn the interest of Tennyson and William Morris back to their connections with Marlborough and its Mound – or ‘Merlin’s Barrow’, as the burghers of the town claimed.
Not only has the Mound stimulated some of the region’s most enduring threads of mythology, it has also been recognised as a feature of considerable historical significance. It was the motte on which the keep of Marlborough Castle was built fifty years after the Norman Conquest. Subsequently, it became the centrepiece of a major seventeenth century garden. The latest research, however, has extended its history back by three millennia.
Recent coring of the Mound at Marlborough College has produced four samples of charcoal, allowing radiocarbon dating for the first time. The samples, which came from different levels in the Mound, were taken from two bore holes through the height of the 19m monument, showing that it was built in the years around 2400 BC. This is the first positive evidence proving the theory that the castle motte is in fact a re-used prehistoric structure of the highest national standing.
Jim Leary, who led the recent archaeological investigations for English Heritage at the nearby Silbury Hill, and is co-author of the recently published ‘The Story of Silbury Hill’ coordinated EH’s contribution, which also included radiocarbon dating. He says, “This is an astonishing discovery. The Marlborough Mound has been one of the biggest mysteries in the Wessex landscape. For centuries people have wondered whether it is Silbury’s little sister; and now we have an answer. This is a very exciting time for British prehistory.”
The Master of Marlborough College is equally enthusiastic: ‘We are thrilled at the discovery of another aspect of our rich history, and one which can be added to the educational opportunities at the school.’
The work is part of a major conservation programme being undertaken by the Marlborough Mound Trust, specially formed at the invitation of the College. The chairman of the Trust says that ‘the inspiration for this was our founder Eric Elstob, a former pupil at the College, whose generous legacy has provided the means for this work. He would have been totally delighted by this news.’
Note: As part of the College grounds, the Mound is strictly on private property. For further details please contact: Donald Insall Associates, 7A Northumberland Buildings, Queen Square, BATH, BA1 2JB Telephone: 01225 469898 Email: [email protected]
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||This article may require copy editing for grammar, style, cohesion, tone, or spelling. (July 2012)|
||This article's lead section may not adequately summarize key points of its contents. (July 2012)|
A memory management unit (MMU), sometimes called paged memory management unit (PMMU), is a computer hardware component responsible for handling accesses to memory requested by the CPU. Its functions include translation of virtual addresses to physical addresses (i.e., virtual memory management), memory protection, cache control, bus arbitration and in simpler computer architectures (especially 8-bit systems) bank switching.
Modern MMUs typically divide the virtual address space (the range of addresses used by the processor) into pages, each having a size which is a power of 2, usually a few kilobytes, but they may be much larger. The bottom n bits of the address (the offset within a page) are left unchanged. The upper address bits are the (virtual) page number. The MMU normally translates virtual page numbers to physical page numbers via an associative cache called a translation lookaside buffer (TLB). When the TLB lacks a translation, a slower mechanism involving hardware-specific data structures or software assistance is used. The data found in such data structures are typically called page table entries (PTEs), and the data structure itself is typically called a page table. The physical page number is combined with the page offset to give the complete physical address.
A PTE or TLB entry may also include information about whether the page has been written to (the dirty bit), when it was last used (the accessed bit, for a least recently used page replacement algorithm), what kind of processes (user mode, supervisor mode) may read and write it, and whether it should be cached.
Sometimes, a TLB entry or PTE prohibits access to a virtual page, perhaps because no physical random access memory has been allocated to that virtual page. In this case the MMU signals a page fault to the CPU. The operating system (OS) then handles the situation, perhaps by trying to find a spare frame of RAM and set up a new PTE to map it to the requested virtual address. If no RAM is free, it may be necessary to choose an existing page (known as a victim), using some replacement algorithm, and save it to disk (this is called "paging"). With some MMUs, there can also be a shortage of PTEs or TLB entries, in which case the OS will have to free one for the new mapping.
In some cases a "page fault" may indicate a software bug. A key benefit of an MMU is memory protection: an OS can use it to protect against errant programs, by disallowing access to memory that a particular program should not have access to. Typically, an OS assigns each program its own virtual address space.
An MMU also reduces the problem of fragmentation of memory. After blocks of memory have been allocated and freed, the free memory may become fragmented (discontinuous) so that the largest contiguous block of free memory may be much smaller than the total amount. With virtual memory, a contiguous range of virtual addresses can be mapped to several non-contiguous blocks of physical memory.
In some early microprocessor designs, memory management was performed by a separate integrated circuit such as the VLSI VI475 (1986) or the Motorola 68851 (1984) used with the Motorola 68020 CPU in the Macintosh II or the Z8015 (1985) used with the Zilog Z8000 family of processors. Later microprocessors such as the Motorola 68030 and the Zilog Z280 placed the MMU together with the CPU on the same integrated circuit, as did the Intel 80286 and later x86 microprocessors.
While this article concentrates on modern MMUs, commonly based on pages, early systems used a similar concept for base-limit addressing, that further developed into segmentation. Those are occasionally also present on modern architectures. The x86 architecture provided segmentation rather than paging in the 80286, and provides both paging and segmentation in the 80386 and later processors (although the use of segmentation is not available in 64-bit operation).
Most modern systems divide memory into pages that are 4 - 64 kB in size, often with the possibility to use huge pages from 2 MB to 512 MB in size. Page translations are cached in a TLB. Some systems, mainly older RISC designs, trap into the OS when a page translation is not found in the TLB. Most systems use a hardware-based tree walker. Most systems allow the MMU to be disabled; some disable the MMU when trapping into OS code.
VAX pages are 512 bytes, which is very small. An OS may treat multiple pages as if they were a single larger page, for example Linux on VAX groups 8 pages together, thus the system is viewed as having 4 kB pages. The VAX divides memory into 4 fixed-purpose regions, each 1 GB in size. They are:
Page tables are big linear arrays. Normally this would be very wasteful when addresses are used at both ends of the possible range, but the page table for applications is itself stored in the kernel's paged memory. Thus there is effectively a 2-level tree, allowing applications to have sparse memory layout without wasting lots of space on unused page table entries. The VAX MMU is notable for lacking an accessed bit. OSes which implement paging must find some way to emulate the accessed bit if they are to operate efficiently. Typically, the OS will periodically unmap pages so that page-not-present faults can be used to let the OS set an accessed bit.
ARM architecture based application processors implement an MMU defined by ARM's Virtual Memory System Architecture. The current architecture defines PTEs for describing 4 kB and 64 kB pages, 1 MB sections and 16 MB super-sections; legacy versions also defined a 1 kB tiny page. The ARM uses a two-level pagetable if using 4 kB and 64 kB pages, or just a one-level pagetable for 1 MB sections and 16 MB sections.
TLB updates are performed automatically by page-table walking hardware.
The IBM System/370 has had an MMU since the early 1970s; it was initially known as a DAT (Dynamic Address Translation) box. It has the unusual feature of storing accessed and dirty bits outside of the page table. They refer to physical memory rather than virtual memory. They are accessed by special-purpose instructions. This reduces overhead for the OS, which would otherwise need to propagate accessed and dirty bits from the page tables to a more physically oriented data structure. This makes OS-level virtualization easier.[clarification needed] These features have been inherited by succeeding mainframe architectures, up to the current z/Architecture.
The DEC Alpha processor divides memory into 8 kB pages. After a TLB miss, low-level firmware machine code (here called PALcode) walks a 3-level tree-structured page table. Addresses are broken down as follows: 21 bits unused, 10 bits to index the root level of the tree, 10 bits to index the middle level of the tree, 10 bits to index the leaf level of the tree, and 13 bits that pass through to the physical address without modification. Full read/write/execute permission bits are supported.
The MIPS architecture supports 1 to 64 entries in the TLB. The number of TLB entries is configurable at CPU configuration before synthesis. TLB entries are dual. Each TLB entry maps a virtual page number (VPN2) to either one of two page frame numbers (PFN0 or PFN1), depending on the least significant bit of the virtual address that is not part of the page mask. This bit and the page mask bits, are not stored in the VPN2. Each TLB entry has its own page size, which can be any value from 1 kB to 256 MB in multiples of 4. Each PFN in a TLB entry has a caching attribute, a dirty and a valid status bit. A VPN2 has a global status bit and an OS assigned ID which participates in the virtual address TLB entry match, if the global status bit is set to 0. A PFN stores the physical address without the page mask bits.
A TLB Refill exception is generated when there are no entries in the TLB that match the mapped virtual address. A TLB Invalid exception is generated when there is a match but the entry is marked invalid. A TLB Modified exception is generated when there is a match but the dirty status is not set. If a TLB exception occurs when processing a TLB exception, a double fault TLB exception, it is dispatched to its own exception handler.
MIPS32 and MIPS32r2 support 32 bits of virtual address space and up to 36 bits of physical address space.
MIPS64 supports up to 64 bits of virtual address space and up to 59 bits of physical address space.
The original Sun 1 was a single-board computer built around the Motorola 68000 microprocessor and introduced in 1982. It included the original Sun 1 Memory Management Unit, that provided address translation, memory protection, memory sharing and memory allocation for multiple processes running on the CPU. All access of the CPU to private on-board RAM, external Multibus memory, on-board I/O and the Multibus I/O ran through the MMU where they were translated and protected in uniform fashion. The MMU was implemented in hardware on the CPU board.
The MMU consisted of a context register, a segment map and a page map. Virtual addresses from the CPU were translated into intermediate addresses by the segment map, which in turn were translated into physical addresses by the page map. The page size was 2 kB and the segment size was 32 kB which gave 16 pages per segment. Up to 16 contexts could be mapped concurrently. The maximum logical address space for a context was 1024 pages or 2 MB. The maximum physical address that could be mapped simultaneously was also 2 MB.
The context register was important in a multitasking operating system because it allowed the CPU to switch between processes without reloading all the translation state information. The 4-bit context register could switch between 16 sections of the segment map under supervisor control which allowed 16 contexts to be mapped concurrently. Each context had its own virtual address space. Sharing of virtual address space and inter-context communications could be provided by writing the same values in to the segment or page maps of different contexts. Additional contexts could be handled by treating the segment map as a context cache and replacing out-of-date contexts on a least-recently-used basis.
The context register made no distinction between user and supervisor states; interrupts and traps did not switch contexts which required that all valid interrupt vectors always be mapped in page 0 of context, as well as the valid Supervisor Stack.
In PowerPC G1, G2, G3, and G4, pages are normally 4 kB. After a TLB miss, the standard PowerPC MMU begins two simultaneous lookups. One lookup attempts to match the address with one of 4 or 8 Data Block Address Translation (DBAT) registers, or 4 or 8 Instruction Block Address Translation registers (IBAT) as appropriate. The BAT registers can map linear chunks of memory as large as 256 MB, and are normally used by an OS to map large portions of the address space for the OS kernel's own use. If the BAT lookup succeeds, the other lookup is halted and ignored.
The other lookup, not directly supported by all processors in this family, is via a so-called "inverted page table" which acts as a hashed off-chip extension of the TLB. First, the top 4 bits of the address are used to select one of 16 segment registers. 24 bits from the segment register replace those 4 bits, producing a 52-bit address. The use of segment registers allows multiple processes to share the same hash table. The 52-bit address is hashed, then used as an index into the off-chip table. There, a group of 8 page table entries is scanned for one that matches. If none match due to excessive hash collisions, the processor tries again with a slightly different hash function. If this too fails, the CPU traps into the OS (with MMU disabled) so that the problem may be resolved. The OS needs to discard an entry from the hash table to make space for a new entry. The OS may generate the new entry from a more-normal tree-like page table or from per-mapping data structures which are likely to be slower and more space-efficient. Support for no-execute control is in the segment registers, leading to 256 MB granularity.
A major problem with this design is poor cache locality caused by the hash function. Tree-based designs avoid this by placing the page table entries for adjacent pages in adjacent locations. An operating system running on the PowerPC may minimize the size of the hash table to reduce this problem.
It is also somewhat slow to remove the page table entries of a process; the OS may avoid reusing segment values to delay facing this or it may elect to suffer the waste of memory associated with per-process hash tables. G1 chips do not search for page table entries, but they do generate the hash with the expectation that an OS will search the standard hash table via software. The OS can write to the TLB. G2, G3, and early G4 chips use hardware to search the hash table. The latest chips allow the OS to choose either method. On chips that make this optional or do not support it at all, the OS may choose to use a tree-based page table exclusively.
The x86 architecture has evolved over a very long time while maintaining full software compatibility even for OS code. Thus the MMU is extremely complex, with many different possible operating modes. Normal operation of the traditional 80386 CPU and its successors (IA-32) is described here.
The CPU primarily divides memory into 4 kB pages. Segment registers, fundamental to the older 8088 and 80286 MMU designs, are not used in modern OSes with one major exception: access to thread-specific data for applications or CPU-specific data for OS kernels, which is done with explicit use of the FS and GS segment registers. All memory access involves a segment register, chosen according to the code being executed. The segment register acts as an index into a table, which provides an offset to be added to the virtual address. Except when using FS or GS as described above, the OS ensures that the offset will be zero. After the offset is added, the address is masked to be no larger than 32 bits. The result may be looked up via a tree-structured page table, with the bits of the address being split as follows: 10 bits for the branch of the tree, 10 bits for the leaves of the branch, and the 12 lowest bits being directly copied to the result. Some operating systems, such as OpenBSD with its W^X feature, and Linux with the Exec Shield or PaX patches, may also limit the length of the code segment, as specified by the CS register, to disallow execution of code in modifiable regions of the address space.
Minor revisions of the MMU introduced with the Pentium have allowed very large 4 MB pages by skipping the bottom level of the tree. Minor revisions of the MMU introduced with the Pentium Pro introduced the Physical Address Extension (PAE) feature, enabling 36-bit physical addresses via three-level page tables (with 9+9+2 bits for the three levels, and the 12 lowest bits being directly copied to the result; large pages become only 2 MB in size). In addition, the Page Attribute Table allowed specification of cacheability by looking up a few high bits in a small on-CPU table.
No-execute support was originally only provided on a per-segment basis, making it very awkward to use. More recent x86 chips provide a per-page no-execute bit in the PAE mode. The W^X, Exec Shield, and PaX mechanisms described above emulate per-page non-execute support on machines x86 processors lacking the NX bit by setting the length of the code segment, with a performance loss and a reduction in the available address space.
x86-64 is a 64-bit extension of x86 that almost entirely removes segmentation in favor of the flat memory model used by almost all operating systems for the 386 or newer processors. In long mode, all segment offsets are ignored, except for the FS and GS segments. When used with 4 kB pages, the page table tree has four levels instead of three. The virtual addresses are divided up as follows: 16 bits unused, 9 bits each for 4 tree levels (total: 36 bits), and the 12 lowest bits directly copied to the result. With 2 MB pages there are only three levels of page table, for a total of 27 bits used in paging and 21 bits of offset. Some newer CPUs also support a 1 GB page with two levels of paging and 30 bits of offset. CPUID can be used to determine if 1 GB pages are supported. In all three cases, the 16 highest bits are required to be equal to the 48th bit, or in other words, the low 48 bits are sign extended to the higher bits. This is done to allow a future expansion of the addressable range, without compromising backwards compatibility.
In all levels of the page table, the page table entry includes a no-execute bit.
Tanenbaum et al., recently stated that the B5000 (and descendant systems) have no MMU. To understand the functionality provided by an MMU, it is instructive to study a counter example of a system that achieves this functionality by other means.
The B5000 was the first commercial system to support virtual memory after the Atlas. It provides the two functions of an MMU in different ways. Firstly, the mapping of virtual memory addresses. Instead of needing an MMU, the MCP systems are descriptor based. Each allocated memory block is given a master descriptor with the properties of the block, i.e., the size, address, and whether present in memory. When a request is made to access the block for reading or writing, the hardware checks its presence via the presence bit (pbit) in the descriptor.
A pbit of 1 indicates the presence of the block. In this case the block can be accessed via the physical address in the descriptor. If the pbit is zero, an interrupt is generated for the MCP (operating system) to make the block present. If the address field is zero, this is the first access to this block and it is allocated (an init pbit). If the address field is non-zero, it is a disk address of the block, which has previously been rolled out, so the block is fetched from disk and the pbit is set to 1 and the physical memory address updated to point to the block in memory (another pbit). This makes descriptors equivalent to a page-table entry in an MMU system. System performance can be monitored through the number of pbits. Init pbits indicate initial allocations, but a high level of other pbits indicate that the system may be thrashing.
Note that all memory allocation is therefore completely automatic (one of the features of modern systems) and there is no way to allocate blocks other than this mechanism. There are no such calls as malloc or dealloc, since memory blocks are also automatically discarded. The scheme is also lazy, since a block will not be allocated until it is actually referenced. When memory is near full, the MCP examines the working set, trying compaction (since the system is segmented, not paged), deallocating read-only segments (such as code-segments which can be restored from their original copy), and as a last resort, rolling dirty data segments out to disk.
Secondly, protection. Since all accesses are via the descriptor the hardware can check all accesses are within bounds, and in the case of a write that the process has write permission. The MCP system is inherently secure and thus has no need of an MMU to provide this level of memory protection. Descriptors are read only to user processes and may only be updated by the system (hardware or MCP). (Descriptors have a tag of 5 and odd-tagged words are read only – code words have a tag of 3.)
Blocks can be shared between processes via copy descriptors in the process stack – thus some processes may have write permission, whereas others not. A code segment is read only, thus reentrant and shared between processes. Copy descriptors contain a 20-bit address field giving index of the master descriptor in the master descriptor array. This also implements a very efficient and secure IPC mechanism. Blocks can easily be relocated since only the master descriptor needs update when a block's status changes.
The only other aspect is performance – do MMU- or non-MMU-based systems provide better performance? MCP systems may be implemented on top of standard hardware that does have an MMU (e.g., a standard PC). Even if the system implementation uses the MMU in some way, this will not be at all visible at the MCP level.
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