1. Department of Biomedical Engineering, Duke University, Durham, NC, USA
2. Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, USA
3. Duke University Marine Laboratory, Nicholas School of the Environment, Beaufort, NC, USA
4. Research Triangle Material Research Science & Engineering Center, Duke University, Durham, NC, USA
5. Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
6. Center for Biomedical Engineering, Department of Chemical and Biological Engineering, University of New Mexico, Albuquerque, NM, USA