1. Department of Neurology; Perelman School of Medicine; University of Pennsylvania; Philadelphia Pennsylvania USA
2. Center for Neurodegenerative Disease Research and Institute on Aging; Perelman School of Medicine; University of Pennsylvania; Philadelphia Pennsylvania USA
3. Department of Biostatistics and Epidemiology; Perelman School of Medicine; University of Pennsylvania; Philadelphia Pennsylvania USA
4. Department of Psychiatry; Perelman School of Medicine; University of Pennsylvania; Philadelphia Pennsylvania USA
5. Avid Radiopharmaceuticals; Philadelphia Pennsylvania USA
6. Department of Pathology and Laboratory Medicine; Perelman School of Medicine; University of Pennsylvania; Philadelphia Pennsylvania USA