流体弹性的影响,在一个活跃的弹性灯丝振荡的出现
Kathryn G Link1, Robert D Guy1, Becca Thomases2
1Department of Mathematics, University of California , Davis, CA 95616, USA.
Journal of the Royal Society, Interface
|May 22, 2024
概括
微生物在复杂液体中的鞭毛跳动受弹性影响. 这项研究揭示了液体粘弹性如何影响鞭毛不稳定性和振荡频率,为微生物运动提供了洞察力.
科学领域:
- 生物物理学的生物物理.
- 流体动力学 流体动力学
- 微生物学 微生物学
背景情况:
- 微生物在复杂的流体中使用鞭毛变形进行推进.
- 旗跳动是由流体力,弹性反应和分子电机引起的.
- 关于流体弹性如何影响鞭毛节拍动力学的数据有限.
研究的目的:
- 为了分析在追随力下粘弹性流体中鞭毛跳动的出现.
- 调查振荡开始对力强度和粘弹性参数的依赖性.
- 了解克拉米多马纳斯 (Chlamydomonas reinhardtii) 的实验观测的机械基础.
主要方法:
- 在粘弹性流体中,由尖端追随力驱动的弹性平面丝线的分析.
- 线性分析以预测振荡开始和频率依赖流体特性.
- 数字模拟用于将模型预测与实验数据进行比较.
主要成果:
- 与牛顿流体相比,需要增加力来诱导粘弹性流体的不稳定性.
- 振荡频率在粘弹性流体中较高,并且随着流体放松时间的增加而增加.
- 模型预测与粘度和Deborah数变化的实验趋势保持一致.
结论:
- 液体的粘弹性显著影响鞭毛体的不稳定性和振荡频率.
- 该模型为观察到的Chlamydomonas reinhardtii*频率变化提供了机制性的解释.
- 这项工作增强了对微生物在复杂的生物流体中运动的理解.
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