在凸障碍物上的细菌散射中翻滚的作用
Theresa Jakuszeit1,2, Ottavio A Croze3
1Institut Curie and Institut Pierre Gilles de Gennes, PSL Research University, CNRS UMR 144, 75005 Paris, France.
Physical review. E
|May 17, 2024
概括
像细菌这样的活跃游泳者因不平衡散射而避免被困在微流体柱上. 这个过程增强了粒子扩散,即使有很多障碍,与简单的反射不同.
科学领域:
- 微观尺度物理学的物理学
- 生物物理学的生物物理.
- 流体动力学 流体动力学
背景情况:
- 流体中的活性推进,比如细菌和Janus粒子,可以导致由于水力动力相互作用而在边界积累.
- 在带有小圆柱体的微流体系统中,自动运动的粒子可能会从表面散落而不是被困.
- 理论上,这种不平衡的散射产生了高粒子扩散率,即使在密集的障碍环境中,与经典反射形成鲜明对比.
研究的目的:
- 为了实验性地研究微流体柱上的推杆状游泳者的不平衡散射.
- 分析细菌"倒"对散射动态和由此产生的粒子扩散性的影响.
- 将实验结果与现有的理论模型进行比较,并探索布在多孔介质中的作用.
主要方法:
- 使用含有圆柱柱的微流体装置来创建障碍格子.
- 微观追踪野生型大肠杆菌 (跑步和) 和光滑游泳突变动物 (仅限跑步) 的运动.
- 量化散射参数,并将它们与散射率的理论预测联系起来.
主要成果:
- 对微流体障碍格子中的推杆式游泳者进行不平衡散射的实验验证.
- 证明将柱子分散起来可以防止长期陷,而不是在平面墙壁上积累.
- 数据表明,散射参数和扩散率受到游泳行为的影响 (运行和倒与仅运行).
结论:
- 不平衡散射是活性粒子在复杂的微流体环境中导航的关键机制.
- 细菌在分散过程中发挥作用,影响在多孔介质中的颗粒扩散.
- 这项研究提供了实验性的洞察力,了解活动物质在受限,结构化流体中的行为.
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