ChE Graduate Seminar Featuring Dr. Nadir Kaplan, Virginia Tech

Abstract: Living systems self-regulate by operating at dynamic optima through feedback loops between mechanics and chemical kinetics, an ability largely missing in synthetic matter. Realizing next-generation materials with analogous capabilities requires exploring these feedback loops outside of purely biological settings. To motivate this core idea, I will first present an integrated theory of cell migration bridging force generation, mechanics, and biochemical signaling, revealing how the mechanics of filopodial protrusions regulates chemical polarization to sustain locomotion. I will then propose a passive physical feedback loop that utilizes the fluid mechanics of viscous flow vortices to design minimal artificial analogs of cell filopodia. Next, I will introduce theory and experiments on "hydrogel diffusiophoresis," a soft deformation pathway driven by solute gradients discovered by my group. I will show how it can potentially close the chemomechanical feedback loop to enable truly active, tissue-like materials. Finally, I will present a first-principles geometric theory of elastic filaments constrained on curved surfaces in a frustrated state. Our solution to this problem paves the way for understanding chemomechanical coupling in biological systems like contractile actin rings on the cell membrane during cytokinesis. Bio: Nadir Kaplan earned his B.S. degree in Engineering Physics from Istanbul Technical University (Turkey), M.S. degree in Physics from Koç University (Turkey), and Ph.D. in Physics from Brandeis University. He then held postdoctoral positions in Applied Math and Materials Science at Harvard School of Engineering and Applied Sciences. Currently, he is an Assistant Professor of Physics at Virginia Tech. His research at the interface of fluid mechanics, elasticity, and geometry is aimed at developing novel theoretical and computational approaches to state-of-the-art materials design. Host: Dr. Sachin Velankar