1. Research Associate, University of Mainz.
2. Research Associate, Home Dialysis Center, Mainz.
3. Medical student, University of Mainz.
4. Professor of Medicine, University of Mainz.
5. Chemical Engineer, Erlangen.
6. Professor of Medicine, Director of Institute for Medical Microbiology, University of Bochum.
7. Professor of Medicine, Director of Laboratory of Clinical Chemistry, University of Mainz.
8. Research Associate, Computer Center, University of Mainz.