1. Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, Texas.
2. Federal Aviation Administration, Office of Commercial Space Transportation, Washington, District of Columbia, and New Space, Associate Editor.
3. Department of Neurology, Center for Space Medicine, Baylor College of Medicine, Houston, Texas.
4. Director, Civil Aerospace Medical Institute, Federal Aviation Administration, and Mike Monroney Aeronautical Center, Oklahoma City, Oklahoma.
5. Aerospace Medicine Consultant, Houston, Texas.