In order to better promote the scientific research on mathematics and related fields, and expand academic horizon of mathematics teachers and students, the disciplines of applied mathematics, probability theory and mathematical statistics in the Department of Mathematics, College of Science invited Professor Pei Yu in the Department of Applied Mathematics of the University of Western Ontario to give an academic Report.

Title: The Impact of Prophage on the Equilibria and Stability of Phage and Host

Reporter: Professor Pei Yu

Time: 2.30-4.00 pm., July 10, 2017(Monday)

Venue: Conference Room in the third floor of Science Building

About the Reporter

Professor Pei Yu graduated from Shanghai Jiao Tong University in 1982 whose major was electronic engineering and computer science. He received his master’s and doctoral degrees in systems design engineering from University of Waterloo in 1984 and 1986, and is now a professor of Applied Mathematics at the University of Western Ontario in Canada. Professor Yu Pei has long been engaged in the research work of nonlinear dynamics, including chaotic dynamical systems, chaotic security and information security, stability and bifurcation of differential equations, bifurcation and chaos control and anti-control etc. He has published more than 180 papers in the SCI indexed journals like the International Journal of Applied Mathematics, and three monographs by the World Book Inc. Professor Pei Yu’ s writings on simplifying bifurcation problems, deriving canonical forms, and calculating have become classic research works in this field. He also serves as the editorial member of many international journals and consultant of some book series. He has very high academic status and international reputation.

Abstract of the Report

In this talk, we present a bacteriophage model that includes prophage, which is described by an 18-dimensional system of ordinary differential equations. This study focuses on asymptotic behavior of the model, and thus the system is reduced to a simple six-dimensional model, involving uninfected host cells, infected host cells and phage. We use dynamical system theory to explore the dynamic behavior of the model, studying in particular the impact of prophage on the equilibria and stability of phage and host. We employ bifurcation and stability theory, centremanifold and normal form theory to show that the system has multiple equilibrium solutions which undergo a series of bifurcations, finally leading to oscillating motions. The results of this study indicate that in some parameter regimes, the host cell population may drive the phage to extinction through diversification, and this prediction holds even if the phage population is likewise diverse. This parameter regime is restricted, however, if infecting phage are able to recombine with prophage sequences in the host cell genome.

Your participation is warmly welcome.