Thomas Powers named Director of Graduate Programs for School of Engineering

Professor Thomas Powers has been named the director of graduate programs at the School of Engineering at Brown University for the 2011-12 academic year.

“Professor Powers was recommended and nominated by several of his colleagues, and I want to thank him for his service to the School of Engineering in filling this vital role,” said Larry Larson, Dean of the School of Engineering.

Professor Powers received an S.B. in physics and an S.B. in mathematics from the Massachusetts Insitute of Technology in 1989. In 1995, he received his Ph.D. in physics from the University of Pennsylvania. After Penn, he held postdoctoral positions in the physics departments of Princeton University and the University of Arizona. Then, he was a postdoctoral fellow at Harvard University. He joined the Division of Engineering of Brown University in 2000 as the first holder of the James R. Rice Term Chair in Solid Mechanics.

Professor Powers' research interests include molecular and cellular biomechanics, the physics of soft matter, and nonlinear dynamics. He is currently an associate editor of Reviews of Modern Physics.

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Hydrodynamics of Microorganisms

Professor Powers' article, Hydrodynamics of Swimming Mircoorganisms, was accepted this week in Reports on Progress in Physics.
Preview the article here: http://dl.getdropbox.com/u/652169/reviseLaugaPowersv3.pdf
Abstract.
Cell motility in viscous fluids is ubiquitous and affects many biological processes, including reproduction, infection, and the marine life ecosystem. Here we review the biophysical and mechanical principles of locomotion at the small scales relevant to cell swimming, tens of microns and below. At this scale, inertia is unimportant and the Reynolds number is small. Our emphasis is on the simple physical picture and fundamental flow physics phenomena in this regime. We first give a brief overview of the mechanisms for swimming motility, and of the basic properties of flows at low Reynolds number, paying special attention to aspects most relevant for swimming, such as resistance matrices for solid bodies, flow singularities, and kinematic requirements for net translation. Then we review classical theoretical work on cell motility, in particular early calculations of swimming kinematics with prescribed stroke and the application of resistive-force theory and slender-body theory to flagellar locomotion. After examining the physical means by which flagella are actuated, we outline areas of active research, including hydrodynamic interactions, biological locomotion in complex fluids, the design of small-scale artificial swimmers, and the optimization of locomotion strategies.

In addition, some of his recent work was highlighted on the NSF news page:
Scientists studying how marine bacteria move have discovered that a sharp variation in water current segregates right-handed bacteria from their left-handed brethren, impelling the microbes in opposite directions. This finding and the possibility of quickly and cheaply implementing the segregation of two-handed objects in the laboratory could have a big impact on industries like the pharmaceutical industry, for which the separation of right-handed from left-handed molecules can be crucial to drug safety.
More here: http://www.nsf.gov/news/news_summ.jsp?cntn_id=114587&org=NSF&from=news

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