Genet, Stéphane and Bruno Delord. A biophysical model of nonlinear dynamics underlying plateau potentials and calcium spikes in Purkinje cell dendrites. J Neurophysiol 88: 2430–2444, 2002; 10.1152/jn.00839.2001. Computational capabilities of Purkinje cells (PCs) are central to the cerebellum function. Information originating from the whole nervous system converges on their dendrites, and their ...

Genet, Stéphane and Bruno Delord. A biophysical model of nonlinear dynamics underlying plateau potentials and calcium spikes in Purkinje cell dendrites. J Neurophysiol 88: 2430–2444, 2002; 10.1152/jn.00839.2001. Computational capabilities of Purkinje cells (PCs) are central to the cerebellum function. Information originating from the whole nervous system converges on their dendrites, and their ...

Evidence of modulated dissipative structures with an intrinsic wavelength in a nonlinear optical system devoid of Turing instability is given. They are found in the transverse field distribution of an optical cavity containing a liquid crystal light valve. Their existence is related to a transition from flat to modulated fronts connecting the unstable middle branch of a bistability cycle and ei...

Contents 1. Introduction 5 1.1. Nonlinear behaviors, time scales, our approach 5 1.2. Electrical activity of cells 6 2. Revisiting the Hodgkin-Huxley equations 10 2.1. Background and formulation 10 2.2. Hodgkin-Huxley gating equations as idealized kinetic models 12 2.3. Dissection of the action potential 13 2.3.1. Current-voltage relations 13 2.3.2. Qualitative view of fast-slow dissection 15 2...

When human subjects hear a sequence of two alternating pure tones, they often perceive it in one of two ways: as one integrated sequence (a single "stream" consisting of the two tones), or as two segregated sequences, one sequence of low tones perceived separately from another sequence of high tones (two "streams"). Perception of this stimulus is thus bistable. Moreover, subjects report on-goin...

We scrutinize the phenomenology arising from a minimal vaccination-epidemic (MVE) dynamics using three methods: mean-field approach, Monte Carlo simulations, and finite-size scaling analysis. The formulation reveals that MVE model exhibits either continuous or discontinuous active-to-absorbing phase transition, accompanied by bistability tricritical point. However, on square lattices, we detect...

Central pattern generators (CPGs) control rhythmic behaviors such as breathing and heartbeat in invertebrates (Calabrese and Marder 1996). Malfunctions in a CPG may have a variety of detrimental effects such as abrupt disruption of breathing, as has been implicated in sudden infant death syndrome (SIDS) (Paydarfar et al. 2005; Moon et al. 2007). In the United States SIDS has been responsible fo...

BACKGROUND Despite a resurgence in control efforts, malaria remains a serious public-health problem, causing millions of deaths each year. One factor that complicates malaria-control efforts is clinical immunity, the acquired immune response that protects individuals from symptoms despite the presence of parasites. Clinical immunity protects individuals against disease, but its effects at the p...

Positive feedback and cooperativity in the regulation of gene expression are generally considered to be necessary for obtaining bistable expression states. Recently, a novel mechanism of bistability termed emergent bistability has been proposed which involves only positive feedback and no cooperativity in the regulation. An additional positive feedback loop is effectively generated due to the i...

A hallmark of positive-feedback regulation is bistability, which gives rise to distinct cellular states with high and low expression levels, and that stochasticity in gene expression can cause random transitions between two states, yielding bimodal population distribution (Kaern et al., 2005, Nat Rev Genet 6: 451-464). In this paper, the probability transition rate and first-passage time in an ...