1. Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA.
2. Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA.
3. Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA 19104, USA.
4. Department of Psychology, Drexel University, Philadelphia, PA 19104, USA.
5. Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA 19104, USA.
6. Department of Physical Medicine and Rehabilitation, University of Pennsylvania, PA 19104, USA.
7. Department of Materials Science and Engineering, Drexel University, Philadelphia, PA 19104, USA.
8. A.J. Drexel Nanomaterials Institute, Drexel University, Philadelphia, PA 19104, USA.
9. Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
10. Department of Diagnostic Imaging, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA.
11. Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA 19104, USA.
12. McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA 19104, USA.
13. Department of Neurology, University of Pennsylvania, Philadelphia, PA 19104, USA.
14. Department of Neurology, Drexel University, Philadelphia, PA 19104, USA.