Bing, Zhitong
Cheng, Zhiyuan
Shi, Danfeng
Liu, Xinkui
Tian, Jinhui
Yao, Xiaojun
Zhang, Jingyun
Wang, Yongfeng
Yang, Kehu
Funding for this research was provided by:
Gansu province funding (1606RJZA016)
Article History
Received: 2 August 2018
Accepted: 9 October 2018
First Online: 6 November 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.