Iima Makoto, Nakagaki Toshiyuki
Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima 739-8251, Japan.
Math Med Biol. 2012 Sep;29(3):263-81. doi: 10.1093/imammb/dqr010. Epub 2011 Jul 12.
We study how the net transport and mixing of chemicals occur in a relatively large amoeba, the true slime mold Physarum polycephalum. The shuttle streaming of the amoeba is characterized by a rhythmic flow of the order of 1 μm/s in which the protoplasm streams back and forth. To explain the experimentally observed transport of chemicals, we formulate a simplified model to consider the mechanism by which net transport can be induced by shuttle (or periodic) motion inside the amoeba. This model is independent from the details of fluid property as it is based on the mass conservation law only. Even in such a simplified model, we demonstrate that sectional oscillations play an important role in net transport and discuss the effects of the sectional boundary motion on net transport in the microorganism.
我们研究化学物质的净传输和混合是如何在一种相对较大的变形虫——多头绒泡菌（一种真正的黏菌）中发生的。这种变形虫的穿梭流动的特征是有节奏的流动，速度约为1微米/秒，原生质在其中来回流动。为了解释实验观察到的化学物质传输，我们构建了一个简化模型，以考虑变形虫内部的穿梭（或周期性）运动诱导净传输的机制。该模型独立于流体性质的细节，因为它仅基于质量守恒定律。即使在这样一个简化模型中，我们也证明了截面振荡在净传输中起着重要作用，并讨论了截面边界运动对微生物中净传输的影响。
