1. German Cancer Research Center (DKFZ); Im Neuenheimer Feld 280 69120 Heidelberg Germany
2. Department of Physics and Astronomy; Ruprecht-Karls-University; Im Neuenheimer Feld 226 Heidelberg Germany
3. Medical Faculty; Ruprecht-Karls-University; Im Neuenheimer Feld 672 Heidelberg Germany
4. Sirona Dental Systems GmbH; Fabrikstraße 31 64625 Bensheim Germany