1. Department of Chemistry, Mercer University, Macon, Georgia 31207, United States
2. Department of Biomedical Sciences, Mercer University School of Medicine, Macon, Georgia 31207, United States
3. Department of Chemistry, Western Illinois University, Macomb, Illinois 61455, United States
4. Department of Biology, Birmingham Southern College, Birmingham, Alabama 35254, United States
5. Norman B. Keevil Institute of Mining Engineering, University of British Columbia, Vancouver V6T 1Z4, Canada