William L. Roper, MD, MPH has served as Dean of the School of Medicine and Vice Chancellor for Medical Affairs of the University of North Carolina at Chapel Hill, and as Chief Executive Officer of the UNC Health Care System, all since 2004. In addition, he has served as a Professor of Pediatrics in the School of Medicine and Professor of Health Policy and Administration in the UNC School of Public Health since 1997. Dr. Roper is a member of the American Academy of Pediatrics and the American Medical Association. He is also currently a director of Davita, Inc. and of Delhaize Group, a member of the Board of Trustees of the Robert Wood Johnson Foundation and Chairman of the Board of Directors of the National Quality Forum. Dr. Roper has served as a director of the Company since December 2007.