为了更好地推动数学及相关领域的科学研究，扩展我校数学学科师生的学术研究视野，理学院数学系应用数学、概率论与数理统计学科特邀加拿大西安大略大学应用数学系Pei Yu教授来我校进行学术讲学。

 Pei Yu教授简介：Pei Yu教授于1982年毕业于上海交通大学电子工程与计算机科学专业，于1984年和1986年在加拿大滑铁卢大学系统设计工程专业获得硕士和博士学位，现为加拿大西安大略大学应用数学系教授。Pei Yu教授长期从事非线性动力学研究工作，包括混沌动力系统、混沌保密与信息安全、微分方程的稳定性与分岔、分岔和混沌的控制与反控制等问题，在国际应用数学SCI检索期刊上发表论文180余篇，在世界图书出版公司出版专著三部。Pei Yu教授在分岔问题的简化和规范型的推导、计算方面的很多工作已经成为这一领域研究的经典文献，是多个国际期刊的编委和系列丛书的顾问，有很高的学术地位和较高的国际知名度。

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

    摘要：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 behaviour 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 behaviour 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.

    时间：2017年7月10日（周一） 下午14：30-17：00

    地点：理学楼三楼会议室

    欢迎广大师生参与交流!