Sharif Digital Repository

Microtubules are hollow cylindrical structures of 25 nanometer diameter inside cell membrane. Microtubule (MT) serves as a cell structure component and vesicular transport inside cell. It has been shown in recent researches that the persistence length in MTs is length dependent and increases about several times of counter length. Also helical structures of MTs have been found recently. In this research using Molecular Dynamic simulation of coarse-grained microtubular structures we compare persistence length of wild and helical microtubular structures. We show that the persistence length in helical structures is independent to the length.
 

Since the first observed case in December 2019, millions of people have been infected by Coronavirus disease 2019 (COVID-¬19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS¬-CoV-¬2). Located on the viral membrane, trimeric spike glycoprotein is one of the most crucial parts of the virus’ structure as it is responsible for the attachment and entry of the virus to host cells. The spike glycoprotein undergoes hinge-like conformational movements and its receptor¬binding domains (RBD) can be in either an accessible (up) state or an inaccessible (down) state to the host cell receptors, such as ACE2. Having performed Molecular Dynamics Simulations and Targeted Molecular... 

The study of active matter has gathered a great deal of attention in the past decades. The collective behavior of living matter such as the murmuration of the flocks of birds is an example of these systems. In order to study different aspects of these systems, variant models have been studied and change of behavior, phase shift and the existence of multiple phases has been observed.Vicsek model was one of the first models studying these systems, where an aligning pairwise interaction causes the agents to move in the same direction.We investigated Vicsek model by considering an overdamped Langevin dynamics for fewparticle systems. We showed Vicsek model in fewparticle systems induces... 

Cells in their surrounding environment subjected to biochemical and biomechanical stimuli and respond to this signals. The mechanism by which cells transduce external mechanical signals into responses is called Mechanotransduction and cell use this mechanism to sense and respond to extracellular signals. Cells control processes like migration and division by mechanosensing. Cell migration is one of the most important responses to Cell-ECM interaction. This migration underlies many biological processes including embryogenesis, wound healing, tumorogenesis, morphogenesis and immune defense, so the study of cell migration is of particular importance. If there are external signals in cells...