Funding for this research was provided by:
Fundamental Research Funds for the Central Universities (FRF-BD-18-016A)
National Natural Science Foundation of China (61802016, 61702506)
Postdoctoral Research Foundation of China (2018M641198)
National Social Science Foundation of China (17ZDA331)
Text and Data Mining valid from 2019-03-19
Received: 14 September 2018
Accepted: 28 February 2019
First Online: 19 March 2019
: The authors declare that they have no competing interests.
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