CAREER: Entropic Elasticity of Fluctuating Filaments and Networks

本项目的研究目标是将有限元法与统计力学的路径积分技术联合收割机结合起来，解决热波动引起的构型熵起重要作用的问题。 力学向生物学和软物质前沿的发展需要对熵力的理解，熵力表现为微米及以下长度尺度的热波动。该建模技术将用于研究两个源自生物学并得到大量实验结果支持的特定力学问题：（a）DNA中蛋白质介导的环的能量学，以及（B）细丝网络的力学行为，例如肌动蛋白和纤维蛋白。所提出的分析DNA环形成的方法与（i）涉及基因调控的DNA结合蛋白的作用和（ii）绘制人类基因组图谱有关。理解丝状网络的机械行为将对操纵细胞的粘附、运动和分化产生影响，因为这些是由细胞与其周围环境之间的机械相互作用控制的。这项活动将导致更好地了解细胞和组织的机械特性如何与疾病有关。它还将使设计新的生物材料和治疗疾病的可能的治疗干预成为可能。此外，还将与当地一家新成立的公司合作，开展与绘制人类基因组图谱有关的项目。 该项目还将为研究生、本科生和高中生提供纳米技术和生物物理学跨学科领域的教育机会。

The research objective of this Faculty Early Career Development (CAREER) project is to combine the finite element method with path integral techniques from statistical mechanics to solve problems in which configurational entropy due to thermal fluctuations plays a significant role. The advance of mechanics towards the frontiers of biology and soft matter necessitates an understanding of entropic forces which manifest themselves as thermal fluctuations at length scales of a micrometer and below. The modeling technique will be used to investigate two specific mechanics problems motivated from biology and backed with a wealth of experimental results: (a) energetics of protein mediated loops in DNA, and (b) mechanical behavior of networks of filaments, such as, actin and fibrin. The proposed methods to analyze DNA loop formation are relevant to (i) the action of DNA binding proteins implicated in gene regulation, and (ii) mapping the human genome. An understanding of the mechanical behavior of filamentous networks will have implications on manipulating adhesion, locomotion and differentiation of cells since these are controlled by mechanical interactions between a cell and its surroundings. This activity will lead to a better understanding of how mechanical properties of cells and tissues are implicated in diseases. It will also enable design of new biomaterials and possible therapeutic interventions for curing diseases. Furthermore, there will be collaboration with a local start-up company on projects related to mapping the human genome. The project will also open up opportunities for educating graduate, undergraduate, and high school students in the interdisciplinary areas of nanotechnology and biophysics.