1. Department of Medicine (K.B.M.), Perelman School of Medicine, University of Pennsylvania, Philadelphia.
2. Department of Physiology (K.B.M., B.L.P.), Perelman School of Medicine, University of Pennsylvania, Philadelphia.
3. Cardiovascular Institute (K.B.M., B.L.P.), Perelman School of Medicine, University of Pennsylvania, Philadelphia.
4. Pennsylvania Muscle Institute (B.L.P.), Perelman School of Medicine, University of Pennsylvania, Philadelphia.