Received: 23 August 2018
Accepted: 8 February 2019
First Online: 15 February 2019
Ethics approval and consent to participate
: Not applicable. According to the University of North Carolina at Chapel Hill Institutional Review Board, this exercise did not fall under human subjects research (Flaherty, personal communication, April 9, 2018).
: Not applicable.
: The authors declare that they have no competing interests.
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