Statistical potentials for 3D structure evaluation:From proteins to RNAs

Structure evaluation is critical to in silico 3-dimensional structure predictions for biomacromolecules such as proteins and RNAs.For proteins,structure evaluation has been paid attention over three decades along with protein folding problem,and statistical potentials have been shown to be effective and efficient in protein structure prediction and evaluation.In recent two decades,RNA folding problem has attracted much attention and several statistical potentials have been developed for RNA structure evaluation,partially with the aid of the progress in protein structure prediction.In this review,we will firstly give a brief overview on the existing statistical potentials for protein structure evaluation.Afterwards,we will introduce the recently developed statistical potentials for RNA structure evaluation.Finally,we will emphasize the perspective on developing new statistical potentials for RNAs in the near future.     

群体迁移行为的理论与实证研究

人类行为往往取决于经济社会的某种趋势性影响, 对其动力学的定量描述和准确理解是当前复杂系统研究的热点. 本文提出由迁移距离, 迁移人口年龄和迁出地经济人口密度所描述的群体迁移欲望函数, 及广义势. 借助于朗之万方程, 将其转变为Hamilton-Jacobi方程, 从而对群体决策行为进行统计理论分析. 采用高维最陡降线的方式求解Hamilton-Jacobi方程. 其解的形式揭示了群体迁移过程中信息熵随着迁移群体年龄的变化呈现一个单峰; 信息熵对迁移距离的二阶导随迁移距离而穿零变化(对应一种相变); 信息熵随着经济人口密度也呈现单峰. 进一步分析信息熵的这些变化规律所蕴含的意义及其机理, 从而获得对人类群体迁移行为的新理解, 为政府管理提供参考和启示.