Funding for this research was provided by:
National Natural Science Foundation of China (81441127)
Key Projects for Academic Support of Top-level Talents in Universities (gxbjZD2016073)
Text and Data Mining valid from 2019-12-01
Received: 15 August 2019
Accepted: 18 November 2019
First Online: 18 December 2019
Ethics approval and consent to participate
: This article does not contain any studies with human participants or animals performed by any of the authors.
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: The authors declare that they have no competing interests.