1. University of North Carolina, Department of Physics and Optical Science, Charlotte, North Carolina 28223, United States
2. Carolinas Medical Center, Department of Urology, Charlotte, North Carolina 28207, United States
3. University of North Carolina, Department of Physics and Optical Science, Charlotte, North Carolina 28223, United StatesbCarolinas Medical Center, Department of Urology, Charlotte, North Carolina 28207, United StatescJohns Hopkins Medical Institutions, Dep