论文标题
分散膜域的持续集体运动
Persistent Collective Motion of a Dispersing Membrane Domain
论文作者
论文摘要
我们研究了嵌入流体膜中的移动夹杂物组装的布朗运动。该运动包括组件的分散，并伴随着其质量中心的扩散。通常，以前的过程比后者快得多，因为质量中心的扩散系数与颗粒数量成反比。但是，在膜夹杂物的情况下，我们发现这两个过程在同一时间尺度上发生，因此大大延长了组装的寿命作为一个集体移动的对象。这种效果是由准二维膜流引起的，这些膜流甚至是组装中最遥远的夹杂物的动作。相同的相关性也会导致质量中心的扩散系数随着时间的流逝而缓慢衰减，从而导致弱亚扩散。我们通过与流介导的相关性的布朗动力学模拟来确认我们的分析结果。这里报告的效果应对纳米尺度膜异质性的稳定性产生影响。
We study the Brownian motion of an assembly of mobile inclusions embedded in a fluid membrane. The motion includes the dispersal of the assembly, accompanied by the diffusion of its center of mass. Usually, the former process is much faster than the latter, since the diffusion coefficient of the center of mass is inversely proportional to the number of particles. However, in the case of membrane inclusions, we find that the two processes occur on the same time scale, thus prolonging significantly the lifetime of the assembly as a collectively moving object. This effect is caused by the quasi-two-dimensional membrane flows, which couple the motions even of the most remote inclusions in the assembly. The same correlations also cause the diffusion coefficient of the center of mass to decay slowly with time, resulting in weak sub-diffusion. We confirm our analytical results by Brownian dynamics simulations with flow-mediated correlations. The effect reported here should have implications for the stability of nano-scale membrane heterogeneities.
