Funding for this research was provided by:
National Natural Science Foundation of China (81522026 and 31570157)
Zhengzhou Tobacco Research Institute, China National Tobacco Corporation (2016SCU04B01)
National Key R&D Program of China (2016YFC1200305)
the Sichuan Outstanding Youth Science & Technology Funding (2016JQ0001)
Text and Data Mining valid from 2018-11-26
Received: 29 July 2018
Accepted: 8 November 2018
First Online: 26 November 2018
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