Funding for this research was provided by:
National Natural Science Foundation of China (81872196, 81672690, 81772900)
Sichuan Province Science and Technology Support Program (2017JQ0040, 2018JY0646)
Text and Data Mining valid from 2019-03-30
Received: 2 December 2018
Accepted: 25 February 2019
First Online: 30 March 2019
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