Funding for this research was provided by:
National Natural Science Foundation of China (81672797 and 81472612)
Beijing Nova Program Interdisciplinary Studies Cooperative Project (Z161100004916043)
National Key Research and Development Program of China (2016YFC1303501 and 2016YFC1303504)
the Science and Technology Planning Project of Beijing City (Z151100003915076)
Article History
Received: 19 December 2017
Accepted: 16 February 2018
First Online: 27 February 2018
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