J.D. Polk has been named the dean of the College of Osteopathic Medicine at Des Moines University. Polk will assume the role on Aug. 1. Polk has worked for the U.S. Department of Homeland Security since 2011, and is currently the assistant secretary for health affairs and chief medical officer. Prior to that, he spent sevenyears in aerospace medicine at NASA. He is also a clinical associate professor of emergency medicine at the Edward Via College of Osteopathic Medicine and an affiliate associate professor and senior fellow in the School of Public Policy at George Mason University.