1. Department of Anesthesia, Womack Army Medical Center, 2817 Reilly Road, Fort Bragg, NC 28310, USA
2. Department of Preventive Medicine (EDC Clinic), Bldg 1-2539 Hamilton Street, Fort Bragg, NC 28310, USA
3. Department of Research Programs, Walter Reed National Military Medical Center, Bethesda, MD 20889, USA
4. Department of Clinical Investigation, Womack Army Medical Center, 2817 Reilly Rd, Fort Bragg, NC 28310, USA