Diana Hernández Diana Hernández studies housing, energy, health and equity with emphasis on evaluating the impacts of policies and structural changes in built environments. Greg Freyer Greg Freyer is one of the School’s most popular classroom instructors, and a 2015 winner of Columbia’s Teaching Excellence award. Barun Mathema Barun Mathema studies infectious disease epidemiology by considering multiple dimensions of transmission. Codruta Chiuzan Codruta Chiuzan studies the development of Phase I clinical trials with particular interest in cancer immunotherapeutic agents. Sara Abiola A lawyer and public health researcher with a focus on the empirical evaluation of health laws, Sara Abiola evaluates government interventions to improve population health. Samantha Garbers Samantha Garbers focuses on the translation of health interventions to promote the health of women, young men, sexual minorities, and other priority populations from research into practice. New Faculty Bios Meet the newest members of our faculty.