1. Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK, USA
2. Deptartment of Radiology, University of Pittsburgh, Pittsburgh, PA, USA
3. Department of Pediatrics and Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
4. College of Precision Instruments and Opto-electronics Engineering, Tianjin University, Tianjin, China