Funding for this research was provided by:
Catholic University of Korea
Received: 8 May 2018
Accepted: 28 June 2018
First Online: 18 July 2018
Ethics approval and consent to participate
: The protocols for this study were approved by the Institutional Review Board of the Catholic University of Korea, and informed consent was obtained from all study participants.
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: The authors declare that they have no competing interests.
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