1. Department of Bioscience and Bioinformatics, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan, National Institute for Nanotechnology, National Research Council of Canada, and Department of Mechanical Engineering, University of Alberta, Edmonton, AB, T6G 2V4 Canada, and Department of Theoretical Studies, Institute for Molecular Science, Okazaki Aichi 444-8585, Japan