Funding for this research was provided by:
National Natural Science Foundation of China (31771449, 31500759, 11672109, 11432006)
Fundamental Research Funds for the Central Universities, SCUT (2017MS084, 2015ZY014)
Guangzhou Science and Technology Program (201707010062)
Text and Data Mining valid from 2019-01-22
Received: 9 February 2018
Accepted: 8 May 2018
First Online: 22 January 2019
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: The authors declare no conflict of interests.
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