1. Department of Human Physiology University of Oregon Eugene OR USA
2. VA Portland Health Care System Portland OR USA
3. Department of Neurology Oregon Health and Science University Portland OR USA
4. KBR, Cardiovascular and Vision Laboratory NASA Johnson Space Center Houston TX USA
5. Department of Biological Sciences Northern Arizona University Flagstaff AZ USA
6. Oregon Heart and Vascular Institute Springfield OR USA
7. Altitude Research Center Division of Pulmonary and Critical Care Medicine Department of Medicine University of Colorado Anschutz Medical Campus Aurora CO USA