1. School of Basic Medical Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu 610000, China
2. School of Mathematical Sciences, Universiti Sains Malaysia, Penang 11800, Malaysia
3. School of Medical Information Engineering, Chengdu University of Traditional Chinese Medicine, Chengdu 610000, China
4. School of Distance Education, Universiti Sains Malaysia, Penang 11800, Malaysia