Roentgen (unit) One roentgen deposits of absorbed dose in dry air, or in soft tissue. One roentgen of X-rays may deposit anywhere from in bone depending on the beam energy. This tissue-dependent conversion from kerma to absorbed dose is called the F-factor in radiotherapy contexts. The conversion depends on the ionizing energy of a reference medium, which is ambiguous in the latest NIST definition. The roentgen has its roots in the Villard unit defined in 1908 by the American Roentgen Ray Society as "the quantity of radiation which liberates by ionisation one esu of electricity per cm of air under normal conditions
Sanford Burnham Prebys Medical Discovery Institute Sanford Burnham Prebys Medical Discovery Institute Sanford Burnham Prebys Medical Discovery Institute (SBP) is a non-profit medical research institute with locations in La Jolla, California, and Orlando, Florida. There are more than 850 scientists at SBP blending fundamental research with drug discovery to address unmet clinical needs in the areas of cancer, neuroscience, immunity, and metabolic disorders. Research at SBP is supported by funding from the National Institutes of Health, National Cancer Institute, and Juvenile Diabetes Research Foundation among others, and partnerships with pharmaceutical companies such as Johnson & Johnson Pharmaceutical Research and Development. In 2008, SBP was awarded a