1. Department of Anatomy, College of Medicine, Korea University, Seoul 02841, Korea
2. Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejon 34141, Korea
3. Fluorescence Core Imaging Center, Ewha Womans University, Seoul 03760, Korea
4. Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea