We gratefully acknowledge the support over the years of: Advanced Digital Imaging Research; CBL Friends, Honda R&D Americas, Inc.; Juvenile Diabetes Foundation; Keck Center for Computational and Structural Biology; MD Anderson Cancer Center; National Institutes of Health; National Science Foundation; Philips Medical Systems; Schlumberger; St. Luke's Episcopal Hospital; Texas Higher Education Coordinating Board; Texas Learning and Computation Center, University of Houston.