1. Center for Integrative Research on Cognition, Learning, and Education, Washington University in St. Louis, St. Louis, MO 63130, USA
2. Department of Chemistry, University of South Florida, Tampa, FL 33620, USA
3. Alabama College of Osteopathic Medicine, Dothan, AL 36303, USA
4. Department of Chemistry, University of Utah, Salt Lake City, UT 84112, USA