Funding for this research was provided by:
Education Department of Sichuan Province (16ZA0047)
973 Program of China (2013CBA01700)
Sichuan Science and Technology Program (2018JY0439, 2018JY0616)
Text and Data Mining valid from 2019-02-06
Received: 13 November 2018
Accepted: 27 January 2019
First Online: 6 February 2019
: The authors declare that they have no competing interests.
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