Funding for this research was provided by:
the National Research Foundation of Korea (NRF-2017S1A3A2067165)
by the Graduate School of YONSEI University Research Scholarship Grants
Article History
First Online: 17 August 2018
Compliance with Ethical Standards
:
: Yoosik Youm, Seungwon Lee, and Ekaterina Baldina declare that they have no conflict of interest.
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