sentences:  After her PhD, she worked at St Thomas's Hospital Medical School, the National Radiological Protection Board, and the Radiation Effects Research Foundation in Hiroshima, before moving to the University of Oxford in 1984.Her major funder since then has been Cancer Research UK.Darby and her team have demonstrated that there is a linear relationship between the dose of radiation delivered incidentally to the heart during breast cancer radiotherapy and the subsequent risk of ischaemic heart disease, and that the absolute size of the radiation-related risk is bigger for women already at increased risk of heart disease.