Funding for this research was provided by:
Ministry of Education, Culture, Sports, Science and Technology (18K17918, 18K11042)
Ministry of Education (NRF-2019S1A5B5A07106956)
Received: 1 May 2020
Accepted: 22 September 2020
First Online: 1 October 2020
Ethics approval and consent to participate
: We ensure that this work has been carried out in accordance with the Code of Ethics of the World Medical Association (Declaration of Helsinki) for experiments involving humans, and informed consent was obtained from all participants. The study protocol was approved by the Comprehensive Human Sciences review board at the University of Tsukuba, Japan.
: This is not applicable as the study does not have an individual person’s data.
: The authors declared that they have no competing interests. This study was carried out in accordance with the guidelines proposed in the Declaration of Helsinki, and informed consent was obtained from all participants. The study protocol was reviewed and approved by the Ethics Committee of the University of Tsukuba in Japan.