1. University of Massachusetts (UMass) Chan Medical School, 55 Lake Avenue North, Worcester, MA 01655, USA
2. School of Mathematical Sciences, Jiangsu University, Zhenjiang 212013, Jiangsu, P. R. China
3. Department of Computer Science and Mathematics, Lebanese American University, Beirut, Lebanon
4. Department of Mathematics, College of Science and Humanities in Al-Kharj, Prince Sattam bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia
5. Department of Basic Engineering Science, Faculty of Engineering, Menoufia University, Shebin El-Kom 32511, Egypt
6. Institute of Space Sciences, R76900 Magurele-Bucharest, Romania