1. Department of Bioengineering,
2. Micro and Nanotechnology Laboratory,
3. Defense System and Analysis Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545
4. Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708
5. Center for Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, Massachusetts 02139
6. Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, Massachusetts 02115
7. Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
8. Department of Maxillofacial Biomedical Engineering and Institute of Oral Biology, School of Dentistry, Kyung Hee University, Seoul 130-701, Republic of Korea
9. Department of Physics, King Abdulaziz University, Jeddah 21569, Saudi Arabia
10. Department of Electrical and Computer Engineering, University of Illinois Urbana-Champaign, Urbana, Illinois 61801;