Figure 2.

Onsager’s “order-disorder” phase-like transition via β in a CRU in numerical simulations under Ca_JSR clamp. (A) Plots of opening rate (k_o) of RyR as a function of Ca_dyad are shown, with our choices of γ, λ, C (Table S3) that keep h = 0 but allow β to vary in a wide range, including near criticality. The inset shows our RyR gating scheme. (B) Examples of spark simulations with phase-like transition via β and emergence of disorder leak in the subcritical regime are shown. Dash lines show the low-bound estimates for open number of RyRs at a steady state (n_∞) in the supercritical and near-critical regimes. (C) “Order-disorder” phase-like transition in terms of median extinction times (100 sparks for each data point) versus β is shown. Arrows show lower and upper bounds estimates for β^∗ obtained analytically (β^∗_{mean_ field} and β^∗_Ising). The phase-like transition happens in the model within these bounds that define the near-critical area. To see this figure in color, go online.