OMAHA, Neb. (AP) — The major freight railroads announced a number of steps Wednesday that they are taking to improve safety in the wake of last month’s fiery Ohio derailment, but it’s not clear if their actions will be enough to satisfy regulators and members of Congress who are pushing for changes. Many of the proposals from the Association of American Railroads trade group focus on strengthening the network of trackside detectors that railroads use to spot problems before they can cause derailments.