Rich Kerswell is a professor in the Department of Applied Mathematics and Theoretical Physics (DAMTP) at the University of Cambridge. His research focuses on fluid dynamics, particularly in the transition to turbulence, geophysical fluid flows, and nonlinear dynamics. Kerswell is known for studying how simple fluid systems can exhibit complex, chaotic behavior and has contributed to understanding turbulence's onset and sustainment in various contexts, including pipes and planetary atmospheres. His work integrates mathematical modeling, theoretical analysis, and computational simulations to explore instabilities and the fundamental mechanisms governing fluid behavior in nature and industry.
It is well known that adding even small amounts of long chain polymers (e.g. few parts per million) to Newtonian solvents can drastically change the flow behaviour by introducing elasticity. In particular, two decades ago, experiments in curved geometries demonstrated that polymer flows can be chaotic even at vanishingly small Reynolds numbers. The situation in `straight’ flows such as pressure-driven flow down a channel is less clear and hence an area of current focus. I will discuss recent progress.
Tension-induced giant actuation in elastic sheets
Dr. Marc Suñé
Buckling is normally associated with a compressive load applied to a slender structure; from railway tracks in extreme heat to microtubules in cytoplasm, axial compression is relieved by out-of-plane buckling. However, recent studies have demonstrated that tension applied to structured thin sheets leads to transverse motion that may be harnessed for novel applications, such as kirigami grippers, multi-stable `groovy-sheets', and elastic ribbed sheets that close into tubes. Qualitatively similar behaviour has also been observed in simulations of thermalized graphene sheets, where clamping along one edge leads to tilting in the transverse direction. I will discuss how this counter-intuitive behaviour is, in fact, generic for thin sheets that have a relatively low stretching modulus compared to the bending modulus, which allows `giant actuation' with moderate strain.
Samir Ghadiali is Professor and Chair/Head of the Department of Biomedical Engineering at the Ohio State University (OSU) and a Professor of Pulmonary and Critical Care Medicine at the OSU Wexner Medical Center. Dr. Ghadiali is a Fellow of the American Institute of Medical and Biological Engineering, the Biomedical Engineering Society and is a Parker B. Francis Fellow in Pulmonary Research. He is a member of the Davis Heart & Lung Research Institute and the Biophysics Graduate Program at OSU, and his internationally recognized research program uses biomedical engineering tools to develop novel diagnostic platforms and drug/gene therapies for cardiovascular and respiratory disorders. His research has been funded by the National Science Foundation, National Institutes of Health, the American Heart Association, and the United States Department of Defense and he has mentored over 35 pre-doctoral and post-doctoral trainees who have gone on to successful academic, industrial and research careers.
The global COVID19 pandemic has highlighted the lethality and morbidity associated with infectious respiratory diseases. These diseases can lead to devastating syndrome known as the acute respiratory distress syndrome (ARDS) where bacterial/viral infections cause excessive lung inflammation, pulmonary edema, and severe hypoxemia (shortness of breath). Although ARDS patients require artificial mechanical ventilation, the complex biofluid and biomechanical forces generated by the ventilator exacerbates lung injury leading to high mortality. My group has used mathematical and computational modeling to both characterize the complex mechanics of lung injury during ventilation and to identify novel ways to prevent injury at the cellular level. We have used in-vitro and in-vivo studies to validate our mathematical predictions and have used engineering tools to understand the biological consequences of the mechanical forces generated during ventilation. In this talk I will specifically describe how our mathematical/computational approach has led to novel cytoskeletal based therapies and how coupling mathematics and molecular biology has led to the discovery of a gene regulatory mechanisms that can minimize ventilation induced lung injury. I will also describe how we are currently using nanotechnology and gene/drug delivery systems to enhance the lung’s native regulatory responses and thereby prevent lung injury during ARDS.