1. School of Life Sciences and Biotechnology, Kyungpook National University, Daegu 702-701, Korea.
2. Hormel Institute, University of Minnesota, Minnesota 55912, USA.
3. Department of Physics, Kyungpook National University, Daegu 702-701, Korea.
4. Department of BT, Kyungpook National University, Sangju 742-711, Korea.
5. Regenerative Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Korea.