北京大学定量生物学中心

 学术报告

题 目：  Energy dissipation in biomolecular devices

报告人： Prof. Lei-Han Tang 

Beijing Computational Science Research Center

时 间：2016-5-25（周三），13:00-14:00

地 点：北京大学老化学楼东配楼一层101报告厅

主持人：汤超 教授

摘 要:

Bimolecular devices perform their function with the support of a power source such as ATP hydrolysis or ion flow. Examples of such devices include transmembrane receptors and molecular motors. The relationship between energy dissipation and performance is an interesting biophysics problem which has just begun to be formulated and understood using novel concepts from the statistical mechanics of small systems [1-3]. Here I will report our recent work on two representative models: the potential switching model and the receptor sensory adaptation model. Both models can be solved exactly. The nonequilibrium steady state (NESS) distribution and various response and correlation functions are calculated exactly. Of particularly interest is the violation of the fluctuation-dissipation theorem (FDT) when there is separation between fast and slow variables of the system. Depending on the scheme of the energy input, the detailed balance relation is violated in the dynamics of either the fast variable or the slow variable, leading to qualitatively different behavior. The use of the Harada-Sasa equality [4] in relating violation of the FDT to energy dissipation will be discussed [5].

Reference:

[1]     K. Sekimoto, Stochastic energetics, Lecture Notes in Physics, Berlin Springer-Verlag, Vol. 799 (2010).

[2]     G. Lan, P. Sartori, S. Neumann, V. Sourjik, and Y. Tu, Nature Phys., 8, 422-8 (2012); P. Sartori and Y. Tu, Phys. Rev. Lett. 115, 118102 (2015).

[3]     Shouwen Wang and L.-H. Tang, J Stat Phys: Theory and Experiment, P07025 (2015).

[4]     T. Harada and S.-i. Sasa, Phys. Rev. Lett. 95, 130602 (2005); T. Harada and S.-i. Sasa, Phys. Rev. E 73, 026131 (2006).

[5]     S.-W. Wang, K. Kawaguichi, S.-i. Sasa, and L.-H. Tang, arXiv:1601.04463.

报告人简介:

　　汤雷翰教授，1981年本科毕业于中国科技大学，1987年获得美国Carnegie Mellon University博士学位，曾先后在瑞士、德国、英国和美国哈佛大学作博士后、研究助理，访问研究员等职。1997年开始到香港浸会大学任副教授及正教授。

汤雷翰教授是国际知名理论物理学家，主要从事凝聚态物理，特别是统计物理理论在凝聚态物理中的应用的研究。他在准晶、超导、自旋玻璃、动力学生长、时空混沌、经济物理、生物物理的解析理论和数值模拟研究中取得了重要成果。