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Corresponding authors
a
Center for Engineering Mechanobiology, University of Pennsylvania, Philadelphia, PA 19104, USA
E-mail:
janmey@pennmedicine.upenn.edu, vshenoy@seas.upenn.edu
b
Department of Materials Science and Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA 19104, USA
c
Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA 19104, USA
d
McKay Orthopaedic Research Laboratory, University of Pennsylvania, Philadelphia, PA 19104, USA
e
Institute for Medicine and Engineering, University of Pennsylvania, 3340 Smith Walk, Philadelphia, PA 19104, USA
f
Departments of Physiology, and Physics & Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA