Funding for this research was provided by:
Hunan Provincial Innovation Foundation for Postgraduate (CX2018B417)
Article History
Received: 30 January 2019
Accepted: 7 March 2019
First Online: 11 March 2019
Compliance with ethical standards
:
: There is no conflict of interest in this manuscript, and manuscript is approved by all authors for publication.
: The work described was original research that has not been published previously, and not under consideration for publication elsewhere, in whole or in part. All the authors listed have approved the manuscript that is enclosed.