1. Department of Bioengineering, University of Pennsylvania, 210 S. 33rd Street, 240 Skirkanich
Hall, Philadelphia, Pennsylvania 19104, United States
2. Department of Physics and Astronomy, University of Pennsylvania, 209 S. 33rd Street, David Rittenhouse Laboratory, Philadelphia, Pennsylvania 19104, United States
3. Department
of Neurosurgery, University of Pennsylvania, Stemmler Hall, 3450 Hamilton Walk, Philadelphia, Pennsylvania 19104, United States