A.E. Araiza/ Arizona Daily Star "Daniel Lopez is not a librarian, but one of the nation's first library nurses."Pima County, Arizona has hired a registered nurse to peruse the stacks and assist many of homeless and downtrodden that frequent the county libraries.Building on the success of the San Francisco Public Library's hiring of a social worker in 2010, local library officials are fully committed to helping the underserved segments of their visitor pool.The problem is not an isolated one as Stephanie Inness reports in the Arizona Daily Star:Lopez is Pima County's novel answer to a common issue in public libraries across the country...