1. Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, PA 19104 e-mail:
2. Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, PA 19104
3. Mechanical Engineering and Biomanufacturing Research Institute, Tsinghua University, Beijing 100000, China
4. Shenzhen Biomanufacturing Engineering Laboratory, Shenzhen, Guangdong 518021, China e-mail: