Munk Tobias, Hallatschek Oskar, Wiggins Chris H, Frey Erwin
Arnold Sommerfeld Center and Center for NanoScience, Ludwig-Maximilians-Universität München, Theresienstrasse 37, 80333 München, Germany.
Phys Rev E Stat Nonlin Soft Matter Phys. 2006 Oct;74(4 Pt 1):041911. doi: 10.1103/PhysRevE.74.041911. Epub 2006 Oct 17.
We present a method to investigate the dynamics of a single semiflexible polymer, subject to anisotropic friction in a viscous fluid. In contrast to previous approaches, we do not rely on a discrete bead-rod model, but introduce a suitable normal mode decomposition of a continuous space curve. By means of a perturbation expansion for stiff filaments, we derive a closed set of coupled Langevin equations in mode space for the nonlinear dynamics in two dimensions, taking into account exactly the local constraint of inextensibility. The stochastic differential equations obtained this way are solved numerically, with parameters adjusted to describe the motion of actin filaments. As an example, we show results for the tumbling motion in shear flow.
我们提出了一种方法来研究单个半柔性聚合物在粘性流体中受各向异性摩擦时的动力学。与先前的方法不同，我们不依赖离散的珠-杆模型，而是引入了连续空间曲线的合适的简正模式分解。通过对刚性细丝的微扰展开，我们在模式空间中导出了一组封闭的耦合朗之万方程，用于二维非线性动力学，精确考虑了不可伸长性的局部约束。以这种方式得到的随机微分方程通过数值求解，调整参数以描述肌动蛋白丝的运动。作为一个例子，我们展示了剪切流中翻滚运动的结果。
