1. ARTORG Center, Medical Faculty, University of Bern, Bern, 3008 Switzerland
2. Pulmonary Medicine Department, University Hospital of Bern, Bern, 3008 Switzerland
3. Thoracic Surgery Department, University Hospital of Bern, Bern, Switzerland
4. Department of Biomedical Engineering, Rutgers University, Piscataway, New Jersey, 08854, USA