Excitable pulses are among the most widespread dynamical patterns that occur in many different systems, ranging from biological cells to chemical reactions and ecological populations. Traditionally, the mutual annihilation of two colliding pulses is regarded as their prototypical signature. Here we show that colliding excitable pulses may exhibit solitonlike crossover and pulse nucleation if the system obeys a mass conservation constraint. In contrast to previous observations in systems without mass conservation, these alternative collision scenarios are robustly observed over a wide range of parameters. We demonstrate our findings using a model of intracellular actin waves since, on time scales of wave propagations over the cell scale, cells obey conservation of actin monomers. The results provide a key concept to understand the ubiquitous occurrence of actin waves in cells, suggesting why they are so common, and why their dynamics is robust and long-lived.

中文翻译：

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兴奋的孤子：在质量守恒的活化剂-抑制剂介质中的An灭，交叉和脉冲成核

令人兴奋的脉冲是在许多不同系统中发生的最广泛的动力学模式之一，从生物细胞到化学反应和生态种群，这些系统均如此。传统上，两个碰撞脉冲的相互an灭被视为其典型特征。在这里，我们表明，如果系统遵循质量守恒约束，则碰撞的可激发脉冲可能会表现出孤子状的交叉和脉冲成核。与以前没有质量守恒的系统中的观察结果相反，在各种参数上都可以稳健地观察到这些替代碰撞情况。我们证明了我们使用细胞内肌动蛋白波模型的发现，因为在整个细胞尺度上的波传播的时间尺度上，细胞服从肌动蛋白单体的守恒。