Funding for this research was provided by:
National Outstanding Youth Foundation of China (11325212)
Key Programme (91530319)
The National Key Basic Research and Development Program (2014CB744100)
Text and Data Mining valid from 2019-02-22
Received: 1 November 2018
Accepted: 24 January 2019
First Online: 22 February 2019
: The authors declare that they have no competing interests.
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