Funding for this research was provided by:
National Natural Science Foundation of China (21506039, 31760452, 31560448)
Natural Science Foundation of Guangxi Province (2016GXNSFAA380140, 2015GXNSFBA139052)
Article History
Received: 26 March 2018
Accepted: 19 June 2018
First Online: 17 July 2018
Compliance with Ethical Standards
:
: The authors declare that they have no conflict of interest.