Funding for this research was provided by:
National Natural Science Foundation of China (61363025)
National Natural Science Foundation of China project (61751314)
Natural Science Foundation of Guangxi (2017GXNSFDA198033)
Scientific Research and Technology Development Program of Guangxi (AB17195055)
Text and Data Mining valid from 2019-02-18
Received: 25 October 2018
Accepted: 24 January 2019
First Online: 18 February 2019
: The authors declare that they have no competing interests.
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