1. Occupational and Aerospace Psychiatry Group, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
2. International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Japan
3. Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Japan
4. Forestry and Forest Products Research Institute, Forest Research and Management Organization, Tsukuba, Japan
5. Program in Human Biology, School of Integrative and Global Majors, University of Tsukuba, Tsukuba, Japan
6. Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, Japan