Department of Mathematics and Statistics, South Dakota State University, Brookings, SD, USA.|Department of Biology and Microbiology, South Dakota State University, SD, USA.|Department of Internal Medicine, Sanford Research, University of South Dakota Sanford School of Medicine.|School of Mathematics, Shandong University.|Department of Agronomy, Horticulture, and Plant Science, Bioinformatics and Mathematical Biosciences Lab, South Dakota State University.