Locomotion and Transport in a Liquid Crystal

液晶中的运动和传输

基本信息

批准号：
1437195
负责人：
Thomas Powers
金额：
$ 27万
依托单位：
Brown University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2014
资助国家：
美国
起止时间：
2014-09-01 至 2019-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1437195&HistoricalAwards=false
关键词：
Locomotion Transport Liquid Crystal

项目摘要

The goal of the proposed study is to investigate the fundamentals of swimming of microorganisms in liquid crystal environments. Swimming and swarming of microorganisms is a topic of considerable current interest, with a lot of research left to be done in the case of swimming in fluids that are more complex than water. Results of this work will deepen our understanding of the behavior of microorganisms in complex yet very relevant systems, such as mucus and biofilms. The PI will continue to participate in the Research Experiences for Teachers program, which invites K-12 teachers from local schools to the Brown campus to participate in laboratory research and course development projects during the summer, and in the Brown University Summer High School program , giving lectures and demonstrations on the physics of locomotion and liquid crystals. The PI will also contribute lectures and discussions to the Providence After School Alliance (PASA), a local organization that provides expanded learning opportunities to high school students.The goal of the proposed research is to provide the theoretical framework for understanding the swimming of microorganisms in liquid crystal solutions. These liquid crystal solutions are model systems for the study of more complicated anisotropic biological systems, but are also interesting in their own right as a means for manipulating active colloidal particles. While the hydrodynamic interactions between microscopic swimmers in Newtonian fluids, such as water, have received a lot of attention, bacteria commonly colonize environments laden with polymers. Since these polymers are typically rod-like and aligned, these environments are often anisotropic. For example, extracellular DNA forms parallel bundles in biofilms, and bacteria have been observed to swim preferentially along the direction of alignment. Furthermore, several experimental groups have recently begun to study swimming bacteria in nontoxic synthetic liquid crystal solutions. The proposal is addressing this issue exactly, the development of a theory that would describe phenomena that are experimentally observed.

该研究的目的是研究微生物在液晶环境中游泳的基本原理。微生物的游泳和集群是当前人们非常感兴趣的话题，对于在比水更复杂的液体中游泳的情况还有大量研究要做。这项工作的结果将加深我们对复杂但非常相关的系统（例如粘液和生物膜）中微生物行为的理解。 PI将继续参加教师研究经验计划，该计划邀请当地学校的K-12教师在夏季到布朗校园参加实验室研究和课程开发项目，并参加布朗大学暑期高中计划，进行有关运动和液晶物理学的讲座和演示。 PI 还将为普罗维登斯课后联盟 (PASA) 提供讲座和讨论，该联盟是一个为高中生提供更多学习机会的当地组织。拟议研究的目标是为理解微生物在水中的游泳提供理论框架。液晶溶液。这些液晶溶液是用于研究更复杂的各向异性生物系统的模型系统，但其本身作为操纵活性胶体颗粒的手段也很有趣。虽然牛顿流体（例如水）中的微观游泳者之间的流体动力学相互作用受到了广泛关注，但细菌通常在充满聚合物的环境中定殖。由于这些聚合物通常呈棒状且排列整齐，因此这些环境通常是各向异性的。例如，细胞外 DNA 在生物膜中形成平行束，并且观察到细菌优先沿着排列方向游动。此外，几个实验小组最近开始研究在无毒合成液晶溶液中游动的细菌。该提案正是解决这个问题，发展一种描述实验观察到的现象的理论。