RUI: Particle Dynamics: Swimming Cells and Sheared Particulate Materials

* 技术摘要 * 本项目利用粒子和细胞的跟踪进行复杂非线性系统的新研究。 其中一个项目是研究单细胞游泳生物的流体动力学，这种生物利用双鞭毛中的分子马达推动自己通过流体。 计划调查的诱导速度场和游泳细胞产生的混合，它们彼此之间的相互作用，集体行为，变形鞭毛的力学，以及光对细胞的限制。 这项工作将扩展我们对微生物流体动力学和统计物理的理解。 第二次调查探讨了剪切层的粘性颗粒，这提供了一个很有前途的模型系统，了解无序固体的机械故障的变形和故障。 这项工作包括培训本科研究人员学习如何进行独立研究，博士后学者学习如何成功地指导学生。 游泳运动员的工作与某些疾病有关，这些疾病涉及鞭毛功能异常，而包装失效模式的工作有助于颗粒材料的改进。 * 非技术摘要 * 本项目利用粒子和生物细胞的视频跟踪对复杂系统进行新的研究。 其中一个项目探索了游泳的单细胞生物的行为，这些生物利用包含在称为鞭毛的突起中的分子马达来推动自己穿过周围的流体。 这项工作可能最终导致深入了解疾病涉及鞭毛功能异常。 计划调查的游泳细胞产生的流体混合，它们之间的相互作用，它们的鞭毛的变形，以及它们的光限制。 第二项研究研究了粘性颗粒层的变形和破裂，这可能有助于设计特别坚固的固体。 所有这些工作包括本科研究人员学习如何进行独立研究，博士后学者学习如何成功地指导学生。 首席研究员还深入参与旨在改善本科物理教育的项目。

*****TECHNICAL ABSTRACT*****This project utilizes the tracking of particles and cells for novel investigations of complex nonlinear systems. One project is a study of the fluid dynamics of swimming single celled swimming organisms that utilize molecular motors contained within twin flagella to propel themselves through a fluid. Investigations are planned of the induced velocity fields and mixing produced by swimming cells, their interactions with each other, collective behavior, the mechanics of the deforming flagella, and the confinement of cells by light. This work will extend our understanding of the fluid dynamics and statistical physics of microorganisms. A second investigation explores the deformation and failure of sheared layers of cohesive particles, which provides a promising model system for understanding the mechanical failure of disordered solids. This work includes the training of undergraduate investigators learning how to conduct independent research and postdoctoral scholars learning how to mentor students successfully. The work on swimmers is connected to certain diseases involving abnormalities of flagellar function, and the work on failure modes of packings can contribute to the improvement of particulate-based materials. *********NON-TECHNICAL ABSTRACT*********This project utilizes the video tracking of particles and biological cells for novel investigations of complex systems. One project explores the behavior of swimming single-celled organisms that utilize molecular motors contained within protrusions called flagella to propel themselves through the surrounding fluid. This work may eventually lead to insight into diseases involving abnormalities of flagellar function. Investigations are planned of the fluid mixing produced by swimming cells, their interactions with each other, the deformations of their flagella, and their confinement by light. A second investigation studies the deformation and breaking of layers of cohesive particles, which could contribute to the design of solids that are especially strong. All of this work includes undergraduate investigators learning how to conduct independent research and postdoctoral scholars learning how to mentor students successfully. The Principal Investigator is also deeply involved in projects designed to improve undergraduate physics education.