Department of Public Health Sciences, Medical University of South Carolina, Charleston; Calgary Stroke Program, Department of Clinical Neurosciences, Medicine, Radiology and Community Health Sciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, AB, Canada; Office of Clinical Research, National Institute of Neurological Disorders and Stroke, National Institutes of health, Bethesda, MD; Department of Neurology, University of Miami Miller School of Medicine, FL.