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Attribution-NonCommercial-NoDerivs 3.0 United States

This is an open access article, originally published at https://doi.org/10.1530/EC-18-0453
Except where otherwise noted, this item's license is described as Attribution-NonCommercial-NoDerivs 3.0 United States This is an open access article, originally published at https://doi.org/10.1530/EC-18-0453