Funding for this research was provided by:
National Natural Science Foundation of China (81430066, 91731314, 31621003, 81602459)
National Basic Research Program of China (2017YFA0505500)
Strategic Priority Research Program of the Chinese Academy of Sciences (XDB19000000)
Article History
Received: 11 October 2017
Accepted: 25 May 2018
First Online: 5 June 2018
Ethics approval and consent to participate
: Not applicable.
: The authors declare that they have no competing interests.
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