Funding for this research was provided by:
National Natural Science Foundation of China (31601370)
China Postdoctoral Science Foundation (171305)
PhD Start-up Foundation of Northwest A&F University (Z109021616)
Basic Scientific Research Foundation of Northwest A&F University (Z109021705)
Text and Data Mining valid from 2018-05-04
Received: 27 November 2017
Accepted: 22 April 2018
First Online: 4 May 2018
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