1. Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan, Department of Material and Life Science, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan, and Biomimetics Research Center, Doshisha University, Kyo-Tanabe, Kyoto 610-0321, Japan