細菌鞭毛集體旋轉的時空結構分析

Abstract

在這篇論文中，將利用簡單模型Microorganism-flagellum-rotor matrix (MFRmatrix)來摹擬真實世界中繁複的細菌鞭毛集體行為。系統藉由介質液體與轉子(rotor)間的液力耦合，細菌鞭毛陣列在培養基板上產生多樣化的圖像。每根細菌鞭毛，均是一個有效的微小剛體模型，由內部的扭矩和彼此間的耦合力推動周圍的流體。流體力學交互作用(hydrodynamic interaction)的長距離性質在鞭毛間產生多樣的動力學行為，包括相序同步和self-proliferating螺旋波。我們發現小系統出現一種隨時間週期變化的特殊“平行波”狀態，其深深地受初始條件的影響。於此基礎，增加在週期性邊界條件下，觀察系統是否具有區域同步化的行為，可與磁軸區域性磁化的現象類比。

In this study, we propose simple Microorganism-flagellum-rotor matrix (MFRmatrix) model to mimick real circumstances and complex bacteria flagellum rotation behavior. We study synchronization of an array of rotors on a substrate that are coupled by hydrodynamic interaction. Each flagellum, which is effectively modeled by a rigid rotor, is driven by an internal torque and exerts an active force on the surrounding fluid. The long-ranged nature of the hydrodynamic interaction between the rotors causes a rich pattern of dynamical behaviors including phase ordering and self-proliferating spiral waves. We find that plane waves (parallel wave) which comes from small systems strongly depend on the initial condition. After adding periodic boundary conditions to the circumstance of the bacterial carpet, we can compare how the bacterial carpet changes with magnetization phenomenon