1. Department of Mathematics and Statistics, York University, Toronto, Ontario M3J 1P3, Canada
2. Zu Chongzhi Center for Mathematics and Computational Sciences, Division of Natural and Applied Sciences, Duke Kunshan University, 8 Duke Ave., Kunshan, Jiangsu 215316, China
3. Department of Applied Mathematics, Illinois Institute of Technology, Chicago, Illinois 60616, USA
4. Department of Physiology and Biophysics, Rush University, Chicago, Illinois 60612, USA
5. Research Centre for Mathematics, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai 519087, China
6. Division of Science and Technology, BNU—HKBU United International College, Zhuhai 519087, China