Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Physical Sciences and Mathematics
Period-Doubling Bifurcation In An Array Of Coupled Stochastically Excitable Elements Subjected To Global Periodic Forcing, Robert Rovetti
Period-Doubling Bifurcation In An Array Of Coupled Stochastically Excitable Elements Subjected To Global Periodic Forcing, Robert Rovetti
Mathematics Faculty Works
The collective behaviors of coupled, stochastically excitable elements subjected to global periodic forcing are investigated numerically and analytically. We show that the whole system undergoes a period-doubling bifurcation as the driving period decreases, while the individual elements still exhibit random excitations. Using a mean-field representation, we show that this macroscopic bifurcation behavior is caused by interactions between the random excitation, the refractory period, and recruitment (spatial cooperativity) of the excitable elements.
Macroscopic Consequences Of Calcium Signaling In Microdomains: A First-Passage-Time Approach, Robert Rovetti
Macroscopic Consequences Of Calcium Signaling In Microdomains: A First-Passage-Time Approach, Robert Rovetti
Mathematics Faculty Works
Calcium (Ca) plays an important role in regulating various cellular processes. In a variety of cell types, Ca signaling occurs within microdomains where channels deliver localized pulses of Ca activating a nearby collection of Ca-sensitive receptors. The small number of channels involved ensures that the signaling process is stochastic. The aggregate response of several thousand of these microdomains yields a whole-cell response which dictates the cell behavior. Here, we study the statistical properties of a population of these microdomains in response to a trigger signal. We use a first-passage-time approach to show analytically how Ca release in the whole cell …