Chen, Yingxi
Hall, Aron J
Kirk, Martyn D
Article History
First Online: 24 February 2017
Compliance with Ethical Standards
:
: Yingxi Chen, Aron Hall and Martyn Kirk declare no conflict of interest.
: This article does not contain any studies with human or animal subjects performed by any of the authors.
: All reported studies/experiments with human or animal subjects performed by the authors have been previously published and complied with all applicable ethical standards (including the Helsinki declaration and its amendments, institutional/national research committee standards, and international/national/institutional guidelines).
: The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.
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