Funding for this research was provided by:
Guangxi Natural Science Foundation of China (2014GXNSFFA118005)
the Ba Gui Scholar Program of Guangxi Zhuang Autonomous Region of China (2014A002)
Text and Data Mining valid from 2018-09-03
Received: 2 April 2018
Accepted: 15 August 2018
First Online: 3 September 2018
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