Funding for this research was provided by:
National Natural Science Foundation of China (31600615)
Natural Science Foundation of Shaanxi Province (2016JQ8023)
China Postdoctoral Science Foundation (2015M582796)
Text and Data Mining valid from 2018-05-02
Received: 20 September 2017
Accepted: 10 April 2018
First Online: 2 May 2018
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