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When necessary, Scholars Portal crosswalks metadata from the publisher's XML/SGML to a Scholars Portal version of NLM XML. The repository creates preservation metadata for each file. The preservation level, explained in the Preservation Implementation Plan, is applied to each file upon ingest and recorded in the preservation metadata for each file.
Acceptable Formats
For the Full Preservation level for journal articles, currently acceptable formats include PDF and XML. XML articles may have diagrams in GIF, JPG, or PNG format. Articles not in these formats (or those unable to be converted to these formats) may still be preserved at the Bit-level Preservation level.
Supplementary materials will be accpeted in any format, and preserved at the Bit-level preservation level.