1. Department of Engineering, Cambridge University, Cambridge CB2 1PZ, UK; Brigham and Women’s Hospital, Harvard Medical School, Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02139
2. MOE Key Laboratory for Strength and Vibration, Xi’an Jiaotong University, Xi’an 710049, P.R. China
3. Department of Engineering, Cambridge University, Cambridge CB2 1PZ, UK
4. School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 Singapore, Singapore