New York Times: As many as 55 workers at a national laboratory may have been exposed to low levels of radiation after an experiment overheated, releasing radioactive particles into the air, the agency operating the lab said Saturday. While the size of the accident was small, it received intensive coverage in Japan’s news media, a reflection of the anxiety over nuclear safety since the Fukushima accident two years ago. The president of the Japan Atomic Energy Agency, which ran the lab, resigned last week over…