1. Department
of Radiology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, United States
2. Vanderbilt
University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
3. Department
of Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01655, United States
4. Department
of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
5. Division
of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee 37232, United States
6. Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee 37232, United States