1. Division of Neurosurgery, Nishinihon Hospital, Higashi-ku, Kumamoto 861-8034, Japan
2. Department of Environmental Medicine, Kurume University School of Medicine, Asahi-machi, Kurume 830-0011, Japan
3. Diving Engineering Department, Chugoku Diving Company Limited, Iwakuni 740-0032, Japan
4. Corporate Planning Department, 2nd team, Oriental Shiraishi Corporation, Koto-ku, Tokyo 135-0061, Japan