1. Faculty of Chemistry and Chemical Biology; Otto-Hahn Str. 6, TU Dortmund 44227 Dortmund Germany
2. Department of Cell Morphology and Molecular Neurobiology; Ruhr-University Bochum; 44801 Bochum Germany
3. Dortmunder Elektronenspeicherringanlage (DELTA); Maria-Goeppert-Meyer Str. 2, TU Dortmund 44227 Dortmund Germany