For scientific journal articles and other resources obtained from the Rutgers Libraries, the best way to ensure accessibility is to link directly to the content from the libraries, rather than downloading a PDF and uploading it to Canvas. The libraries are working with all of the content vendors to make sure that they comply with WCAG 2.1 Level AA (though this does not mean that their PDF downloads will be accessible yet).
The libraries highly recommend that instructors utilize the course reading list tool in Canvas, and not just upload files or links to the course. The reading list tool provides numerous benefits to the instructors and students and helps the libraries better understand the material being utilized in courses. Benefits include analytics about how students interact with the assigned material and on-the-go access to the list via the library mobile app.
For any questions on content, you can email rul_accessibility@libraries.rutgers.edu and include a URL for the resource in question.