1. The Cardiovascular Institute (P.D.A., N.N.M., M.L.W., C.C.H., L.P., L.L.C., J.T.-M., M.P.R.), University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6160
2. University of Washington School of Medicine (P.D.A.), Seattle, Washington 98195
3. the Institute for Translational Medicine and Therapeutics (M.L.W., L.P., M.P.R.), University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6160
4. Department of Mathematics (K.F.S.), Georgetown University, Washington, D.C. 20057
5. Institute of Diabetes Obesity and Metabolism (M.R.R., R.S.A., M.P.R.), University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6160