Funding for this research was provided by:
National Natural Science Foundation of China (41871205)
Text and Data Mining valid from 2019-03-12
First Online: 12 March 2019
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: This manuscript has not been published or presented elsewhere in part or in entirety and is not under consideration by another journal. We have read and understood your journal’s policies, and we believe that neither the manuscript nor the study violates any of these. On behalf of all authors, the corresponding author states that there is no conflict of interest.