Emergence of intelligence by cell shape changes in a giant amoeboid cell of the true slime mold Physarum

活细胞是一种通过复杂的化学反应动态工作的智能化学系统。本研究的目的是从分子同步性的角度阐明细胞的组织结构，旨在为制造功能材料提供新的指导方针。我们以大型变形生物--真粘菌多头绒泡菌的原虫为研究对象，通过模拟研究了(1)时间顺序的组织、(2)细胞形状的优化设计和(3)动态同步的机制。时间顺序的组织通过分析细胞形态的长期变化，发现了7个振荡成分，周期从几秒到10h不等。所有其他振荡现象，如细胞周期、形态发生和原生质的周期性流动，都符合这7个周期中的某一个。当i=1，2，3.2时，在周期Ti：Ti+1/Ti=7.5和Ti+2/Ti+1=2.8之间存在以下几何级数。运输静脉网…的优化设计更多的工作：当许多食物来源被放置在均匀分布的有机体上的不同位置时，原生质聚集在食物上，而静脉则来自不同的网络。对网络的几何形状进行了统计分析，发现网络的几何形状满足有效网络的多重要求：管道总长度短，连接紧密(任意两个食品站点之间的中转食物站点数量较少)，以及对意外断开管道的容错性。粘菌动态行为的数学模拟所提出的数学模型是一组非线性偏微分方程组，它考虑了原生质的流动以及通过扩散和张力产生的静水压力在化学振荡之间的相互作用。该模型成功地模拟了实验观察到的典型模式，以及在拥挤条件下吸引人的移动到食物地点(最喜欢的地点)的积累和土丘的形成。较少

A living cell is an intelligent chemical system which works dynamically by complex chemical reactions. The objective of the present research is to elucidate the cellular organization in terms of molecular synchronization with the aim to propose a new guideline for manufacturing functionality materials. We use a large amoeboid organism, the plasmodium of the true slime mold Physarum polycephalum, and study mechanisms of (1) organization of time order, (2) optimal design of cell shape, and (3) dynamical synchronization by simulation.1. Organization of time orderBy analyzing a long-term changes in the cell shape, 7 oscillatory components are found, periods ranging from a few secnds to 10h. All other oscillatory phenomena, such as cell cycle, morphogenesis, and periodic streaming of protoplasm, agree with the some one of the 7 periodicity. The following geometric progression holds among the periods Ti : Ti+1/Ti=7.5 and Ti+2/Ti+1=2.8 with I=1,2,3.2. Optimal design of transportation vein net … More work :When many food-sources were placed at different locations on the uniformly spreading organism, the protoplasm gathers at the food and veins remained from various networks. Geometry of the network is analyzed statistically, and found that the network geometry meets multiple requirements for effective network ; short total length of tubes, close connection (small number of transit food-sites between any two food-sites) and fault-tolerance against an accidental disconnection of tubes.3. Methematical modeling of the dynamic behavior by the slime moldThe proposed mathematical model is a set of nonlinear partial differential equations which take into account the flow of protoplasm and interaction among chemical oscillations via diffusion and hydrostatic oressure generated by tension generation. This model is successful to simulate typical patterns observed experimentally, as well as the accumulation of attractive locomotion to food-site (favorite site) and mound formation in crowed conditions. Less