1. Joint Department of Biomedical Engineering University of North Carolina at Chapel Hill/North Carolina State University Raleigh NC 27695 USA
2. Comparative Medicine Institute North Carolina State University Raleigh NC 27695 USA
3. Department of Chemical and Biomolecular Engineering North Carolina State University Raleigh NC 27695 USA
4. Biomedical Engineering Department of Cell Biology, School of Medicine University of Virginia Charlottesville VA 22903 USA
5. Department of Electrical & Computer Engineering North Carolina State University Raleigh NC 27695 USA