Karma is a popular and useful tool for managing data ingestion in VIVO – particularly for mapping relational data to RDF. Violeta Ilik of Northwestern of Adelphi University has done a lot of work with Karma for VIVO and has put together YouTube videos of the mapping process. The following page contains detailed information about the mapping process: Using the Karma data integration tool.
https://www.youtube.com/channel/UCb9vsw2XvZDzZtEwe0aH9eA
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https://github.com/NUBIC/R2RML-Karma
Additionally - if you are comfortable with Python, there's an example of mapping CSV to RDF for VIVO here: