1. Department of Biomaterials Science, Hiroshima University Faculty of Dentistry, 1-2-3 Kasumi, Minami-Ku, Hiroshima 734-8553, Japan;
2. BIOMAT-Department of Operative Dentistry and Dental Materials, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000, Leuven, Belgium
3. National Space Development Agency of Japan (NASDA), Sengen 2-1-1, Tsukuba, lbaraki 305-8505, Japan
4. Laboratory for Chemical and Biological Dynamics, Department of Chemistry, Catholic University of Leuven, Celestijnenlaan 200D, B-3001 Heverlee, Belgium