is an Associate Radiation Biologist in the Department of Radiation Oncology, Massachusetts General Hospital (MGH) and Associate Professor of Radiation Oncology (Radiation Biology) at Harvard Medical School (HMS). At MGH, Dr. Held leads a team that is involved in research on molecular mechanisms for the induction of bystander effects by high energy particles in cells and tissues, characterization of proton beam induced DNA damage responses, development of a cancer screening platform for personalized radiation medicine, mechanisms for regulation of DNA damage response by cell-cell communication, and development of novel agents for mitigation of radiation-induced pulmonary injury. Dr. Held also teaches radiation biology to radiation oncology medical and physics residents and graduate students at MGH/HMS and the Massachusetts Institute of Technology. Dr. Held earned her PhD in biology from the University of Texas, Austin. She has served on review panels for numerous federal agencies including the National Institutes of Health, the National Aeronautics and Space Administration (NASA), and the U.S. Army Medical Research and Materiel Command programs and other organizations such as the Radiological Society of North America, is on the Editorial Boards of Radiation Research and the International Journal of Radiation Biology, and has served on committees for the National Academy of Science/National Research Council, NASA, and the American Society of Radiation Oncology. She has been a President of the Radiation Research Society and is currently on the Board of Directors and Vice President of Program Area Committee 1 of NCRP, having served as Chair of the Program Committee for the 2011 NCRP Annual Meeting on Scientific and Policy Challenges of Particle Radiations in Medical Therapy and Space Missions.