Taylor P R, Yates C A, Simpson M J, Baker R E
Mathematical Institute, University of Oxford, Woodstock Road, Oxford OX2 6GG, United Kingdom.
Department of Mathematical Sciences, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom.
Phys Rev E Stat Nonlin Soft Matter Phys. 2015 Oct;92(4):040701. doi: 10.1103/PhysRevE.92.040701. Epub 2015 Oct 2.
Diffusive transport is a universal phenomenon, throughout both biological and physical sciences, and models of diffusion are routinely used to interrogate diffusion-driven processes. However, most models neglect to take into account the role of volume exclusion, which can significantly alter diffusive transport, particularly within biological systems where the diffusing particles might occupy a significant fraction of the available space. In this work we use a random walk approach to provide a means to reconcile models that incorporate crowding effects on different spatial scales. Our work demonstrates that coarse-grained models incorporating simplified descriptions of excluded volume can be used in many circumstances, but that care must be taken in pushing the coarse-graining process too far.
扩散输运是一种普遍现象，贯穿于生物科学和物理科学之中，扩散模型经常被用于研究扩散驱动的过程。然而，大多数模型都忽略了体积排阻的作用，而体积排阻会显著改变扩散输运，尤其是在生物系统中，其中扩散粒子可能占据了相当一部分可用空间。在这项工作中，我们采用随机游走方法，提供一种手段来协调在不同空间尺度上纳入拥挤效应的模型。我们的工作表明，在许多情况下可以使用纳入了排除体积简化描述的粗粒化模型，但在过度推进粗粒化过程时必须谨慎。
