Ma, Yuan
He, Feng J
Li, Nicole
Hao, Jesse
Zhang, Jing
Yan, Lijing L
Wu, Yangfeng
Article History
Received: 27 May 2015
Revised: 15 September 2015
Accepted: 18 October 2015
First Online: 10 December 2015
Competing interests
: YM is sponsored by the China Scholarship Council. LLY is supported by the National Natural Sciences Foundation of China grants (71233001 and 71490732), UNFPA and the NIH (R01AG023627). The remaining authors declare no conflict of interest.
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