William Eric Uspal's Homepage

A major aim of my research is to elicit complex or "smart" behavior from soft matter systems via judicious design of micro and nano scale components and driving forces. We know that soft matter, organized on these scales, is capable of extraordinary behavior because of what we see in biological systems -- therefore, another of my interests is unraveling the physics of living matter. I generally proceed through theoretical modeling, numerical simulation, and development of insight into the underlying physics, as I find that there is virtuous feedback between all three. I have also developed rewarding collaborations with experimentalists.

I am currently working in the Doyle Group at MIT on dynamic self-assembly and collective behavior of particles in microfluidic devices. Flowing suspensions of particles are driven into highly dissipative, non-equilibrium configurations by sustained influx of energy. Spatial and dynamical patterns beyond those obtained in traditional self-assembly (which is based on minimization of free energy) are possible. Fascinating collective behavior (e.g. swarming, "microfluidic crystals") can arise from long-range many-body hydrodynamic interactions.

I've recently gotten interested in synchronization, dynamical phase transitions, persistent structures in hydrodynamics, and the connections between chaos, irreversibility, and deterministic diffusion (though I don't purport to be an expert on any of these!)

Publications

W.E. Uspal and P.S. Doyle, "Tunable self-organization of flowing crystals in microfluidic channels", in preparation.
W.E. Uspal, H.B. Eral, and P.S. Doyle, "Engineering particle trajectories in microfluidic flows using particle shape", submitted.
J.S. Leith, A. Tafvizi, F. Huang, W.E. Uspal, P.S. Doyle, A.R. Fersht, L.A. Mirny, and A.M. van Oijen, "Sequence-dependent sliding kinetics of p53", Proc. Natl. Acad. Sci., 109, 16552-16557, 2012. pdf reprint
W.E. Uspal and P.S. Doyle, "Collective dynamics of small clusters of particles flowing in a quasi-two-dimensional microchannel", Soft Matter, 8, 10676-10686, 2012. pdf reprint
W.E. Uspal and P.S. Doyle, "Scattering and Nonlinear Bound States of Hydrodynamically Coupled Particles in a Narrow Channel", Phys. Rev. E, 85, 016325, 2012. pdf reprint
A. Alexeev, W.E. Uspal and A.C. Balazs, "Harnessing Janus Nanoparticles to Create Controllable Pores in Membranes", ACS Nano, 2, 1117-1122, 2008. web link
K.A. Smith and W.E. Uspal, "Shear-driven release of a bud from a multicomponent vesicle", J. Chem. Phys., 126, 075102, 2007. web link

Links

I like to collect free online course notes, books, and study material: Sklogwiki on statistical mechanics and soft matter. Mike Luke has an excellent set of QFT lecture notes based on the course given by Sidney Coleman. Suzanne Fielding on hydrodynamic stability. A book about the boundary element method. Lectures on theoretical biophysics. Pedagogical examples in physics. Statistical mechanics and thermodynamics. Of course, there's always MIT OpenCourseWare.

Richard Jones' Soft Machines is an excellent soft matter/nanotech blog. I've learned a lot about climate change from RealClimate.