Funding for this research was provided by:
Ministry of the Environment
Text and Data Mining valid from 2019-02-22
Received: 22 October 2018
Accepted: 15 February 2019
First Online: 22 February 2019
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of the National Institute for Environmental Studies, the Core Center of JECS and the Ethics Committee of Tohoku University School of Medicine on 10th December 2015 (reference number 2015–1-559). The JECS is conducted in accordance with the Helsinki Declaration and other relevant national and international regulations, and written informed consent was obtained from all participants.
: Not applicable.
: The authors declare that they have no competing interests.
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