1. Biophysics Graduate Group, University of California, Davis, California 95616, United States
2. Institut Laue-Langevin, BP 156, 38042 Grenoble, France
3. Stanford Synchrotron Radiation Lightsource, Menlo Park, California 94025, United States
4. Department of Chemical Engineering and Materials Science, University of California, Davis, California 95616, United States
5. Department of Biomedical Engineering, University of California, Davis, California 95616, United States