About the Authors

Kun Wei

kunwei@ymail.com (KW); mahong@scu.edu.cn (HM)

Affiliations College of Mathematics, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China, College of Life Sciences, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China

Shilong Gao

Affiliation College of Mathematics, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China

Suchuan Zhong

Affiliation College of Mathematics, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China

Hong Ma

kunwei@ymail.com (KW); mahong@scu.edu.cn (HM)

Affiliation College of Mathematics, Sichuan University, Chengdu, Sichuan Province, People’s Republic of China

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: KW HM. Performed the experiments: KW. Analyzed the data: KW SG SZ. Contributed reagents/materials/analysis tools: SG SZ. Wrote the paper: KW HM.