Permanent charge effects on ionic flow

时   间：  2022-03-04 10:00 — 11:00

Permanent charge is the most important structure of an ion channel (or protein) and is the main responsible controller for properties of ionic flows through the ion channel. In this talk, we will report our studies toward an understanding of  permanent charge effects on ionic flow via a 
quasi-one-dimensional Poisson-Nernst-Planck (PNP) model.  
The permanent charges considered here are restricted to a special case of piecewise constant with one non-zero portion. For ionic mixtures with one cation (positively charged) species and one anion (negatively charged) species, a fairly rich behavior of permanent charge effects has been revealed from rigorous analyses based on a geometric framework for PNP and from numerical simulations guided by the analytical results.   For ionic mixtures with three ion species: two cation species and one anion species, richer behavior is expected and our preliminary analysis and a case study  identify,  in concrete manner, a number of these, including some not-so-intuitive behaviors. 
The talk will be based on works collaborated with B. Eisenberg,  W. Huang,  S. Ji,  N. Sun,  L. Zhang,  M. Zhang