1. Department of Polymer Science and Maurice Morton Institute of Polymer Science, The University of Akron, Akron, OH 44325—3909
2. Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
3. Materials Directorate, Wright Laboratory, WL/MLPJ, Wright-Patterson AFB, OH 45433—7702
4. Biotechnology Division, Natick Research, Development, and Engineering Center, U.S. Army, Natick, MA 01760—5020