1 Joint Bioinformatics Graduate Program, Department of Information Science, George W. Donaghey College of Engineering and Information Technology, University of Arkansas at Little Rock, USA.
2 University of Arkansas for Medical Sciences, 2801 S. University Ave, Little Rock, AR 72204, USA.
3 School of Computer Science, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, PA 15213, USA.
4 Department of Statistics, Harvard University, Cambridge, MA 02138, USA.
5 Divisions of Bioinformatics and Biostatistics, National Center for Toxicological Research, US Food and Drug Administration, 3900 NCTR Road, Jefferson, AR 72079, USA.