Professor in the History of Science at Princeton University, studies twentieth-century biomedical research. She is the author of The Life of a Virus: Tobacco Mosaic Virus as an Experimental Model, 1930-1965 (2002), and Life Atomic: A History of Radioisotopes in Science and Medicine (2013). Her next book is on science and regulation in the 1960s through the 1980s, focusing on how researchers conceptualized and developed techniques for detecting environmental carcinogens.