Funding for this research was provided by:
National Natural Science Foundation of China (11661065)
Scientific Research Fund of Jiangxi Provincial Education Department (GJJ151264, GJJ151267, GJJ161261)
Text and Data Mining valid from 2018-01-15
Received: 8 September 2017
Accepted: 31 December 2017
First Online: 15 January 2018
: The author declares to have no conflicts of interest.