| Affiliation: | 1. Division of Pulmonary and Critical Care Medicine, University of Minnesota, MMC # 276, 420 Delaware Street Southeast, Minneapolis, MN 55045, USA;2. Division of Environmental and Occupational Health Sciences, National Jewish Health, 1400 Jackson Street, G212, Denver, CO 80206, USA;3. Division of Pulmonary and Critical Care Sciences, Environmental Occupational Health Department, School of Medicine, Colorado School of Public Health, University of Colorado, Denver, CO, USA;1. Department of Pulmonary and Cardiac Rehabilitation, J. Paul Sticht Center on Aging and Rehabilitation, Wake Forest Baptist Medical Center, Medical Center Boulevard, Winston Salem, NC 27157, USA;2. Department of Internal Medicine, Section on Pulmonary Medicine, Critical Care, Allergy and Immunologic Diseases, Wake Forest Baptist Medical Center, Medical Center Boulevard, Winston Salem, NC 27157, USA |
