Funding for this research was provided by:
Natural Science Foundation of Hubei Province (2017CFA026)
Scientific Research Project of Hubei Provincial Education Department (Q20141610)
Text and Data Mining valid from 2019-03-27
Received: 12 September 2018
Revised: 12 February 2019
Accepted: 12 March 2019
First Online: 27 March 2019
Compliance with Ethical Standards
: All authors declare that they have no conflict of interest.
: This article does not contain any studies with human participants or animals performed by any of the authors.