Funding for this research was provided by:
National Natural Science Foundation of China (U1706218, 41576011)
Postdoctoral Sustentation Fund of Qingdao (861805033068)
Text and Data Mining valid from 2019-01-15
Received: 21 September 2018
Accepted: 1 January 2019
First Online: 15 January 2019
: The authors declare that they have no competing interests.
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