Funding for this research was provided by:
National Natural Science Foundation of China (31601875, 31772531)
Strategic Priority Program of CAS (XDB11010200)
Text and Data Mining valid from 2018-09-25
Received: 13 June 2018
Accepted: 31 August 2018
First Online: 25 September 2018
: Ethics approval was not needed for the study.
: Not applicable.
: The authors declare that they have no competing interests.
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