标题： 活性丝状阵列中的动力学被捕获的团簇 显示英文标题

标题： Kinetically arrested clusters in active filament arrays

摘要： 我们使用布朗动力学模拟和理论研究了流体渗透的排列整齐且间距相等的活性弹性丝的过阻尼时空动力学及模式形成现象。这些丝的一端被固定，另一端自由。这些丝被建模为具有活动性的连接胶体链，活动性通过沿丝主轴作用的压缩性追随力来体现。链的长度小于热持久长度。对于一系列丝间距和活动值范围，我们发现丝阵列最终会自组装成一系列规则间隔且动力学被捕获的紧凑簇。丝的活动性、几何形状、弹性以及接枝密度都被观察到对簇的大小、形状和间距起关键作用。此外，不同接枝密度下的簇形状可以通过与活动相关的标度指数重新缩放为自相似形式。我们推导出了理论表达式，这些表达式将簇中的丝数量和簇之间的间距与丝活动性、丝弹性以及接枝密度联系起来。我们的研究结果揭示了聚集体形成过程中涉及的物理机制，并表明空间接触力和摩擦力平衡了活性力和丝弹性以稳定聚集体。我们的模拟还提出了基于活性胶体或合成微管-马达系统的丝基聚集体及其类似生物仿生材料的设计原则。 显示英文摘要

摘要： We use Brownian dynamics simulations and theory to study the over-damped spatiotemporal dynamics and pattern formation in a fluid-permeated array of equally spaced, active, elastic filaments that are pinned at one end and free at the other. The filaments are modeled as connected colloidal chains with activity incorporated via compressive follower forces acting along the filament backbone. The length of the chains is smaller than the thermal persistence length. For a range of filament separation and activity values, we find that the filament array eventually self-assembles into a series of regularly spaced, kinetically arrested, compact clusters. Filament activity, geometry, elasticity, and grafting density are each seen to crucially influence the size, shape, and spacing of emergent clusters. Furthermore, cluster shapes for different grafting densities can be rescaled into self-similar forms with activity-dependent scaling exponents. We derive theoretical expressions that relate the number of filaments in a cluster and the spacing between clusters, to filament activity, filament elasticity, and grafting density. Our results provide insight into the physical mechanisms involved in the initiation of clustering and suggest that steric contact forces and friction balance active forces and filament elasticity to stabilize the clusters. Our simulations suggest design principles to realize filament-based clusters and similar self-assembling biomimetic materials using active colloids or synthetic microtubule-motor systems.