New York University and the government of Abu Dhabi said this week that an investigative firm headed by a former federal prosecutor had been hired to conduct an inquiry into labor conditions at the university’s new Middle East campus. The move comes a month after The New York Times reported on widespread labor abuses in the construction of N.Y.U. Abu Dhabi, which opens to students in the fall. The firm, Nardello & Company, which has offices around the world, will “conduct an independent review of allegations of labor violations,” N.Y.U. announced on Wednesday, “with a focus on those recently reported in the media.”