Funding for this research was provided by:
National Natural Science Foundation of China (61505018, 21603020 & 51503022)
Natural Science Foundation of Yongchuan district (2016nc1001)
Technology Project from Chongqing Education Committee (KJ1401113 & KJ1501116)
Chongqing Science & Technology Commission (cstc2016jcyjys0006 & cstc2016jcyjA0451)
Received: 21 November 2017
Accepted: 21 December 2017
First Online: 15 January 2018
: The authors declare that they have no competing interests.
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