Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Mechanisms of stochastic onset and termination of atrial fibrillation
  episodes: Insights using a cellular automaton model   Mathematical models of cardiac electrical excitation are increasingly
complex, with multiscale models seeking to represent and bridge physiological
behaviours across temporal and spatial scales. The increasing complexity of
these models makes it computationally expensive to both evaluate long term (>60
seconds) behaviour and determine sensitivity of model outputs to inputs. This
is particularly relevant in models of atrial fibrillation (AF), where
individual episodes last from seconds to days, and inter-episode waiting times
can be minutes to months. Potential mechanisms of transition between sinus
rhythm and AF have been identified but are not well understood, and it is
difficult to simulate AF for long periods of time using state-of-the-art
models. In this study, we implemented a Moe-type cellular automaton on a novel,
topologically correct surface geometry of the left atrium. We used the model to
simulate stochastic initiation and spontaneous termination of AF, arising from
bursts of spontaneous activation near pulmonary veins. The simplified
representation of atrial electrical activity reduced computational cost, and so
permitted us to investigate AF mechanisms in a probabilistic setting. We
computed large numbers (~10^5) of sample paths of the model, to infer
stochastic initiation and termination rates of AF episodes using different
model parameters. By generating statistical distributions of model outputs, we
demonstrated how to propagate uncertainties of inputs within our microscopic
level model up to a macroscopic level. Lastly, we investigated spontaneous
termination in the model and found a complex dependence on its past AF
trajectory, the mechanism of which merits future investigation.

28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
6
The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
25
The categories of this paper are: patt-sol
23
The categories of this paper are: solv-int
22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph