1University of Maryland, College Park, Baltimore, MD.
2University of Maryland, College Park, College Park, MD.
3University of North Carolina at Chapel Hill, Chapel Hill, NC.
4University of Minnesota, Minneapolis, MN.
5University of South Carolina, Columbia, SC.
6San Diego State University, San Diego, CA.
7University of Arizona, Tucson, AZ.
8Tulane University School of Public Health and Tropical Medicine, New Orleans, LA.