Roentgen (unit) absorbed dose in a wide range of matter. When measuring absorbed dose in a human due to external exposure, the SI unit the gray, or the related non-SI rad are used. From these can be developed the dose equivalents to consider biological effects from differing radiation types and target materials. These are equivalent dose, and effective dose for which the SI unit sievert or the non-SI rem are used. The following table shows radiation quantities in SI and non-SI units: Roentgen (unit) The roentgen or röntgen () (symbol R) is a legacy unit of measurement for the exposure of X-rays
Sanford Burnham Prebys Medical Discovery Institute In 2007, T. Denny Sanford gave the Institute $20 million through Sanford Health, a hospital which received significant donations from T. Denny Sanford previously, allowing it to create the Sanford Children's Health Research Center, which has sites in Sioux Falls, South Dakota and La Jolla, CA, the latter within the campus of SBP. In 2010, the Institute adopted the name Sanford-Burnham Medical Research Institute following a $50 million pledge of support from Sanford. An anonymous gift of $275 million was made in 2014. In 2015, the Institute changed its name again to Sanford Burnham Prebys Medical Discovery Institute following a