Human hepatitis delta virus (HDV) is the smallest RNA virus in genome. HDV genome is divided into a viroid-like sequence and a protein-coding sequence which could have originated from different resources and the HDV genome was eventually constituted through RNA recombination. The genome subsequently diversified through accumulation of mutations selected by interactions between the mutated RNA a...

We construct a new gating model and develop a new theory to study the escaping process of a ligand out of a spherical cavity with a puncture ~or gate! on the surface. The gate undulation can be regulated by any time-dependent function and the motion of the ligand inside the spherical cavity is mapped into a two-dimensional entropy potential surface. Hence the driving force of our model is entro...

In this study, the problem of navigation in dynamic and unknown environment is investigated and a navigation method based on force field approach is suggested. It is assumed that the robot performs navigation in...