Limit Cycles and Excitable Systems

In course

Description

This lecture covers the concepts of limit cycles and excitable systems, focusing on the relationship between unstable spirals in region R and the oscillations in glycolysis. It also discusses the bistability possible in positive feedback systems and the phase locking phenomenon. The instructor explains the drift time calculation and phase-dependent shifts in human circadian rhythms, emphasizing the response to external stimuli.

Instructors (2)

Official source

https://mediaspace.epfl.ch/media/0_tuwmxsft

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Related concepts (55)

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Circadian rhythm sleep disorders (CRSD), also known as circadian rhythm sleep-wake disorders (CRSWD), are a family of sleep disorders which affect the timing of sleep. CRSDs arise from a persistent pattern of sleep/wake disturbances that can be caused either by dysfunction in one's biological clock system, or by misalignment between one's endogenous oscillator and externally imposed cues. As a result of this mismatch, those affected by circadian rhythm sleep disorders have a tendency to fall asleep at unconventional time points in the day.

Phase-locked loop

A phase-locked loop or phase lock loop (PLL) is a control system that generates an output signal whose phase is related to the phase of an input signal. There are several different types; the simplest is an electronic circuit consisting of a variable frequency oscillator and a phase detector in a feedback loop. The oscillator's frequency and phase are controlled proportionally by an applied voltage, hence the term voltage-controlled oscillator (VCO).

Bacterial circadian rhythm

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Circadian clock

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