Funding for this research was provided by:
Beijing Natural Science Foundation of China (9174042)
Humanities and Social Science Foundation of Ministry of Education (16YJC630017)
National Natural Science Foundation of China (91746116, 71603018, 71432002, 71804009)
Beijing Social Science Foundation (17GLC043, 17JDGLB008)
Beijing Excellent Talent Project (2015000020124G047)
Beijing Institute of Technology Research Fund Program for Young Scholars (3210012261598)
Article History
Received: 27 July 2018
Accepted: 18 December 2018
First Online: 5 January 2019
Ethics approval and consent to participate
: All procedures performed in studies involving human participants were with ethics approval from an independent research ethics committee in China (No. KYX2016007).
: Not applicable.
: The authors declare that they have no competing interests.
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