1. Pulmonary and Critical Care Unit; Massachusetts General Hospital; Boston Massachusetts
2. Cardiovascular Epidemiology Research Unit; Department of Medicine; Beth Israel Deaconess Medical Center; Boston Massachusetts
3. Obesity Prevention Program, Department of Population Medicine; Harvard Medical School/Harvard Pilgrim Health Care Institute; Boston Massachsetts
4. Channing Laboratory; Department of Medicine; Brigham and Women's Hospital; Boston Massachusetts
5. Department of Environmental Health; Harvard School of Public Health; Boston Massachusetts