Funding for this research was provided by:
Hunan Provincial Science and Technology Department (2018GK1020)
National Natural Science Foundation of China (71850012)
National Natural Science Foundation of China (71871090)
Text and Data Mining valid from 2019-01-30
Received: 26 October 2018
Accepted: 15 January 2019
First Online: 30 January 2019
: The authors declare that they have no competing interests.
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