About the Authors

Xiangrong Li

Affiliation Guangxi Colleges and Universities Key Laboratory of Mathematics and Its Applications, College of Mathematics and Information Science, Guangxi University, Nanning, Guangxi, P.R. China

Xupei Zhao

Affiliation Mathematics and Physics Institute of Henan University of Urban Construction, Pingdingshan, Henan, P. R. China

Xiabin Duan

Affiliation Guangxi Colleges and Universities Key Laboratory of Mathematics and Its Applications, College of Mathematics and Information Science, Guangxi University, Nanning, Guangxi, P.R. China

Xiaoliang Wang

xliangwang@126.com

Affiliation Guangxi Colleges and Universities Key Laboratory of Mathematics and Its Applications, College of Mathematics and Information Science, Guangxi University, Nanning, Guangxi, P.R. China

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: XZ XW XL. Performed the experiments: XZ XW. Analyzed the data: XW XD. Contributed reagents/materials/analysis tools: XL XZ XW. Wrote the paper: XW XZ.