Theory of frequency response of mechanically driven cardiomyocytes

Figure 1. An example of the time evolution of the phase in Eq. 2 (top row) - and the resulting oscillation in χ(t) (bottom row), with ωc = 2π, ωp = 6π. (A) Q = 0.2, below threshold of entrainment at Q = 1, the cell beat with its spontaneous frequency ωc as indicated by the quasi-linear increase in phase. Inset: comparison to linear slope (dashed) that shows large regions of slips and much smaller intervals of plateaus. (B) Q = 0.97 Intermittent periods of entrainment (plateaus) followed by fast “phase-slip” events. This corresponds to the “bursting” behavior observed in experiments23. (C) Q = 2, above the threshold of entrainment. The cell beats with the probe frequency ωp.

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