1. Tissue Engineering Program, Life Sciences Institute, National University of Singapore, Singapore.
2. Department of Orthopaedic Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
3. Department of Biomedical Engineering, College of Engineering, Peking University, Beijing, P.R. China.
4. Center for Biomaterials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, P.R. China.