Funding for this research was provided by:
Young Scientists Fund (51702094)
Natural Science Foundation of Hunan Province (2017JJ3014)
Article History
Received: 18 January 2019
Accepted: 18 February 2019
First Online: 20 February 2019
Compliance with ethical standards
:
: The authors declare no conflict of interest.
Free to read: This content has been made available to all.