Li, Yongqiang
Jia, Anning
Qiao, Yan
Xiang, Jun
Zhang, Yongjiang
Wang, Wenhe
Funding for this research was provided by:
Beijing Municipal Education Commission (KM201610020008)
Beijing Municipal Commission of Education (CEFF-PXM2017_014207_000043)
National key research and development program (2016YFF0203203)
Article History
Received: 13 October 2017
Accepted: 11 December 2017
First Online: 26 December 2017
Compliance with ethical standards
:
: All authors declare that we have no conflict of interest.
: This article does not contain any studies with human participants or animals performed by any of the authors.