Funding for this research was provided by:
National Natural Science Foundation of China (51679180)
National Social Science Foundation of China (15BGL048)
Hubei Province Science and Technology Support Project, China (2015BAA072)
Article History
Received: 20 July 2018
Revised: 6 August 2018
Accepted: 10 August 2018
First Online: 20 August 2018