1. Department of Anesthesiology, Duke University Medical Center, Durham, NC, USA
2. Department of Medicine, Duke University Medical Center, Durham, NC, USA
3. Center for the Study of Aging and Human Development, Duke University Medical Center, Durham, NC, USA
4. Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, USA
5. Center for Cognitive Neuroscience, Duke Institute for Brain Sciences, Duke University, Durham, NC, USA
6. Midwest Orthopaedics at Rush, Rush University Medical Center, Chicago, IL, USA
7. Department of Surgery, Duke University Medical Center, Durham, NC, USA