Richard J. Cohen, the Whitaker Professor in Biomedical Engineering in the MIT Institute for Medical Engineering and Science (IMES) and a faculty member in the Harvard-MIT Program in Health Sciences and Technology (HST), has seen a lot during his years at MIT. He is a rare “MIT lifer,” rising from student to senior faculty member and spending half a century at the Institute. Cohen joined HST as a first-year medical student in 1971 and then inaugurated the MD/PhD track by enrolling in the MIT physics PhD program — receiving…