1. The State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
2. Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
3. Department of Radiology, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania 19104, United States
4. Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States