1. Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, Illinois.
2. Hines Veterans Administration Hospital, Hines, Illinois.
3. National Synchrotron Light Source, Brookhaven National Laboratory, Upton, New York.
4. Department of Bioengineering, Rice University, Houston, Texas.
5. Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri.