1. Division of Environmental Engineering Science, Gunma University, Kiryu, Japan
2. Silk Materials Research Unit, National Agriculture and Food Research Organization (NARO), Tsukuba, Japan
3. Metallurgy Research Team, Kyoto Municipal Institute of Industrial Technology and Culture, Kyoto, Japan
4. Sericulture Research Group, Gunma Sericultural Technology Center, Maebashi, Japan
5. Department of Future Industry-oriented Basic Science and Materials, Toyota Technological Institute, Nagoya Japan