WASHINGTON (AP) — U.S. industrial production slowed to a 0.4% gain in August as shutdowns of petroleum refineries and petrochemical plants caused by Hurricane Ida curbed manufacturing activity. Plant closures long the Gulf Coast as well as lost oil production during last month’s hurricane shaved 0.3 percentage points from output, the Federal Reserve reported Wednesday. Industrial output had risen a revised 0.8% in July. Industrial production covers manufacturing, utilities and mining. For just manufacturing, factory output slowed to a tiny 0.2% gain, reflecting the hurricane impact and continued supply chain troubles.