1. Department of Environmental Health, University of Fukui School of Medicine, Japan
2. Department of Environmental Medicine, Kochi University School of Medicine, Japan
3. Department of Diagnostic Radiology, Radiology and Nuclear Medicine, Radiological Clinic, Miners’ Hospital, Germany
4. Department of Radiology, Finnish Institute of Occupational Health, Finland
5. Department of Radiology, University of Fukui School of Medicine, Japan
6. Department of Radiology, National Hospital Organization Kinki-Chuo Chest Medical Center, Japan
7. Department of Surgery, Fukui Saiseikai Hospital, Japan
8. Koyo Seikyo Hospital, Japan