1. Department of Biomedical Engineering, Michigan Technological University,Houghton, MI 49931, USA
2. US Geological Survey, Virginia Cooperative Fish and Wildlife Research Unit, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061-0321, USA
3. Departments of Pathology and Medicine
4. Department of Orthopaedics and Rehabilitation, The Pennsylvania State University, Hershey, PA 17033, USA