1. Department of Mathematics, Walla Walla University, College Place, WA, USA
2. Department of Mathematical Sciences, Montana State University, Bozeman, MT, USA
3. Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
4. Hyalite Engineers, Bozeman, MT, USA
5. Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA
6. Department of Mathematics, Temple University, Philadelphia, PA, USA