1. University of Nebraska-Lincoln, Lincoln, Nebraska, USA
2. University of Southern California, Los Angeles, California, USA
3. Duquesne University, Pittsburgh, Pennsylvania, USA
4. University of Delaware, Newark, Delaware, USA
5. University of Washington, Seattle, Washington, USA
6. Munroe Meyer Institute, University of Nebraska Medical Center, Omaha, Nebraska, USA
7. Virginia Commonwealth University, Richmond, Virginia, USA