1. Department of Chemistry, University of Washington, Bagley Hall, Box 351700,
Seattle, Washington 981915-1700, United States
2. Laboratoire des Mécanismes
Réactionnels, CNRS, École Polytechnique, Palaiseau, France
3. Waters Corporation, Floats Road, Wythenshawe, Manchester,
M23 9LZ, United Kingdom
4. German Cancer Research Center, Heidelberg,
Germany