This is easy in theory using a regex filter. However, I played with your feed and noticed two things: first, the author name isn't always an author name, eg sometimes there is "Diabetes News and Interest" and then in the article itself a real author is mentioned. It won't be an easy task to work around those cases. Second, the author names syntax. is it always first name [space] last name? the other way around? do you want to filter on last names? first names?