Funding for this research was provided by:
National Natural Science Foundation of China (11674110)
Natural Science Foundation of Guangdong Province (2016A030308010)
Science and Technology Planning Project of Guangdong Province, China (2015B090927006)
Text and Data Mining valid from 2018-12-01
Received: 28 July 2018
Accepted: 13 November 2018
First Online: 5 December 2018
: The authors declare that they have no competing interests.
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