Funding for this research was provided by:
National Institute of General Medical Sciences (U01GM110712)
Received: 31 March 2018
Accepted: 27 September 2018
First Online: 29 October 2018
Ethics approval and consent to participate
: Because this study did not involve the use or collection of any data on living individuals, it did not meet the definition of human subjects research provided by the US Code of Federal Regulations, and thus did not require ethical approval [CitationRef removed]
: Not applicable
: The authors declare that they have no competing interests.
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