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Chapter History

First Online: 21 October 2021

Compliance with Ethical Standards

: <i>Author Contributions</i>: Hiroshi Kobayashi performed the literature search, collected data using the Web database, and contributed to the interpretation of included research studies.

: <i>Funding</i>: No fund.

: <i>Ethical Approval</i>: This article does not contain any studies with human participants or animals.

: <i>Conflict of Interest</i>: Hiroshi Kobayashi declares that he has no conflict of interest.

: <i>Informed Consent (Optional)</i>: For this type of study, formal consent is not required.