1. Department
of Bioengineering and ∥Department of Electrical and Systems Engineering,
School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
2. Division of Gastroenterology and §Division of Hematology-Oncology,
Department
of Medicine, Perelman School of Medicine and ⊥Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States