[1] Department of Bioengineering, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259-B-40 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
[2] Corporate Research Laboratory, Corporate Research Group, Fuji Xerox Co., Ltd., 430 Sakai, Nakai-machi, Ashigarakami-gun, Kanagawa 259-0157, Japan