Roentgen (unit) this derivative quantity the roentgen equivalent physical (rep) to distinguish it from the ICR roentgen. The introduction of the roentgen measurement unit, which relied upon measuring the ionisation of air, replaced earlier less accurate practices that relied on timed exposure, film exposure, or fluorescence. This led the way to setting exposure limits,and the National Council on Radiation Protection and Measurements of the United States established the first formal dose limit in 1931 as 0.1 roentgen per day. The International X-ray and Radium Protection Committee, now known as the International Commission on Radiological Protection (ICRP) soon followed with a limit of
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