1. Advanced Imaging Research Center University of Texas Southwestern Medical Center 5323 Harry Hines Blvd 75390 Dallas Texas USA
2. Department of Chemistry University of Texas at Dallas 800 West Campbell Road 75080 Richardson Texas USA
3. Centre de Biophysique Moléculaire CNRS UPR 4301 Rue Charles Sadron 45071 Orléans Cedex 2 France