Funding for this research was provided by:
National Natural Science Foundation of China (61427801)
National Natural Science Foundation of China (61871446)
Postgraduate Research & Practice Innovation Program of Jiangsu Province (KYCX18 0893)
Text and Data Mining valid from 2018-11-22
Received: 15 June 2018
Accepted: 31 October 2018
First Online: 22 November 2018
: The authors declare that they have no competing interests.
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