Funding for this research was provided by:
National Natural Science Foundation of China (61572070, 61471028, 61871023)
Fundamental Research Funds for the Central Universities (2016JBZ003, 2017JBM004)
Text and Data Mining valid from 2018-11-16
Received: 7 September 2018
Accepted: 31 October 2018
First Online: 16 November 2018
: The authors declare that they have no competing interests.
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