论文标题
几何效应在结构化环境中诱导异常依赖大小的主动转运
Geometric effects induce anomalous size-dependent active transport in structured environments
论文作者
论文摘要
在积极的自propelled系统中不同个体之间的结构化环境中运输效率的变化既难以研究，也很难理解。在这里，我们研究了一个非固有尺寸变化但速度相当均匀的活性原型的非打击{\ ecoli}菌株的传输。我们表明，长期运输从较短细胞的捕获状态转换为较长的较长细胞的较长的态状状态，该状态超过了柱阵列几何形状设置的关键细菌大小。使用实验和建模的组合，我们表明这种异常的尺寸依赖性是由于附近支柱引起的较长细胞的捕获而提高了逃生速率。我们的结果表明，几何效应可能导致大小是在结构化环境中运输的敏感调谐旋钮，这对活性物质系统尤其是对细菌对结构化栖息地的形态适应，社区的空间结构以及抗生物燃料材料的材料设计的影响。
Variations of transport efficiency in structured environments between distinct individuals in actively self-propelled systems is both hard to study and poorly understood. Here, we study the transport of a non-tumbling {\ecoli} strain, an active-matter archetype with intrinsic size variation but fairly uniform speed, through a periodic pillar array. We show that long-term transport switches from a trapping dominated state for shorter cells to a much more dispersive state for longer cells above a critical bacterial size set by the pillar array geometry. Using a combination of experiments and modeling, we show that this anomalous size-dependence arises from an enhancement of the escape rate from trapping for longer cells caused by nearby pillars. Our results show that geometric effects can lead to size being a sensitive tuning knob for transport in structured environments, with implications in general for active matter systems and, in particular, for the morphological adaptation of bacteria to structured habitats, spatial structuring of communities and for anti-biofouling materials design.
