Funding for this research was provided by:
National Natural Science Foundation of China (21403002)
National Natural Science Foundation of China (31601074, 11626052, 61672035, 61300058)
Doctoral Fund of Liaoning Province (201601296)
Article History
Received: 15 August 2017
Accepted: 3 January 2018
First Online: 15 January 2018
Ethics approval and consent to participate
: Not applicable.
: Not applicable.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.