1. Department of Mechanical Engineering, The Pennsylvania State University, 137 Reber Building, University Park, PA 16802, USA
2. Department of Biomedical Engineering and Mechanics Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
3. School of Plant and Environmental Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
4. Department of Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
5. Department of Mechanical Engineering, Virginia Tech, Blacksburg, VA 24061, USA