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
Wilhelm Krause in the field of embryology. Among his better known students at Göttingen was bacteriologist Robert Koch (1843-1910). Krause is credited with the publication of over 100 medical articles. Wilhelm Krause Johann Friedrich Wilhelm Krause (July 12, 1833 – February 4, 1910) was a German anatomist born in Hanover. He was the son of anatomist Karl Friedrich Theodor Krause (1797-1868). In 1854 he earned his medical doctorate, and later (1860) became an associate professor at the University of Göttingen. In 1892 he was appointed head of the Anatomical Institute Laboratory in Berlin. Krause is known for the discovery and description of