Funding. Hengyang Normal University (HYNU) (16D03); National Natural Science Foundation of China (NSFC) (11604216, 61505111, 61605044); China Postdoctoral Science Foundation (2016M600667); Guangdong Science and Technology Department (2016B050501005); Department of Education of Guangdong Province (2016KCXTD006); Natural Science Foundation of Guangdong Province (2015A030313549); Natural Science Foundation of Hunan Province (2016JJ3030).