Nonlinear Dynamics and Pattern Formation in Physics and Biology

小行星9812526 该奖项支持物理和生物系统中的非线性动力学和模式形成的研究。 理论研究以及与实验将集中在细胞生长和运动的领域，并在流体力学的瑞利不稳定性的另一种解释。 第一个领域的工作重点是了解细菌B细胞生长的物理机制。 枯草芽孢杆菌和定向游泳的机制peritrichously鞭毛细菌细胞。 这项工作将阐明导致B超螺旋结构形成的物理过程。枯草芽孢杆菌，当细胞分裂后细胞分离失败时产生，以及与移动的附属结构相关的相关物理生物学。在第二个领域的工作旨在阐明定向游泳的机制，结果时，共同旋转的螺旋鞭毛束在一起。 调查将集中在发生这种情况时发生的流体动力学相互作用和最近在游泳微生物悬浮液中观察到的集体行为。 PI寻求在低雷诺数下融合弹性和流体力学领域的描述，以阐明微生物游泳的物理机制。最近的实验表明，在这种张力驱动的不稳定性的膜囊泡的形状不稳定性的光阱，可能会发生前传播。 受这些实验的启发，PI将研究在粘性两相流中可能发生类似的“传播拓扑转变”的情况。 特别感兴趣的是对流不稳定性的射流和羽流，在射流中的屈曲现象，粘弹性和剪切的作用。 这位才华横溢的PI将在物理学和生物学之间的界面领域进行理论研究。 微生物游动的物理机制和对生物系统特有的各种流体流动的更好理解是研究的主要焦点。 ***

9812526 Goldstein This award supports research on nonlinear dynamics and pattern formation in physical and biological systems. Theoretical research well connected with experiment will focus on the areas of cell growth and motion, and on an alternative explanation of the Rayleigh instability in fluid mechanics. Work in the first area focuses on understanding the physical mechanisms of cell growth in the bacterium B. subtilis and on the mechanism of directed swimming in peritrichously flagellated bacterial cells. The proposed work would elucidate the physical processes that lead to the formation of the supercoiled structure of B. subtilis that results when cell separation fails to occur after cell division, and related physical biology associated with moving filamentary structures. Work in the second area seeks to elucidate the mechanism for directed swimming that results when co-rotating helical flagella bundle together. Inquiry will focus on the hydrodynamic interactions that occur when this happens and on collective behavior recently observed in suspensions of swimming microorganisms. The PI seeks a description that melds the areas of elasticity and hydrodynamics at low Reynolds number to elucidate the physical mechanisms by which microorganisms swim. Recent experiments on shape instabilities of membrane vesicles induced by optical traps that have shown that front propagation may occur in such tension driven instabilities. Motivated by these experiments, the PI will study the circumstances under which an analogous `propagating topological transition' might occur in viscous two-phase flow. Of particular interest are convective instabilities of jets and plumes, buckling phenomena in jets, and the role of viscoelasticity and shear. %%% This talented PI will carry out theoretical research in areas at the interface between physics and biology. The physical mechanisms by which microorganisms swim and a better understanding of kinds of fluid flow peculiar t o biological systems are a major focus of the research. ***