Schaefer D W, Berne B J
Biophys J. 1975 Aug;15(8):785-94. doi: 10.1016/S0006-3495(75)85855-3.
A random-walk model of motility is used to predict the dynamics of fluctuations in the number of particles in a small observation volume. The results show that number fluctuations provide a measure of the mean swimming speed as well as the persistence length. Experimental light-scattering results are presented for three strains of Escherichia coli whose motion appears random-walk in nature. For the strain with th elongest persistence length, excellent agreement is found that theoretical predictions. For the more erratic strains, however, the shape of the measured scattered light intensity correlation functions indicates the presence of a contribution due to orientational fluctuations.
一种运动性的随机游走模型被用于预测小观测体积内粒子数量波动的动力学。结果表明,数量波动提供了平均游动速度以及持久长度的一种度量。给出了三种大肠杆菌菌株的实验光散射结果,它们的运动在本质上呈现随机游走。对于持久长度最长的菌株,发现与理论预测有极好的一致性。然而,对于更不规则的菌株,所测量的散射光强相关函数的形状表明存在由于取向波动引起的贡献。