1. Albert Einstein Medical Center, Sidney Kimmel Medical School, Philadelphia, PA
2. Division of Pulmonary , Critical Care, Sleep Medicine, West Virginia University, Morgantown, WV
3. Clinic for Cardiology, Herz- und Diabeteszentrum NRW, Ruhr-Universität Bochum, Bad Oeynhausen, Germany
4. Willes Consulting Group, Inc., Encinitas, CA