Seeking to break the tension and inform others that he was in the bathroom, Barnes & Noble men's-room- stall occupant Larry Ardell coughed Monday. 'I was alone in the bathroom, taking a dump, when I could hear one or two other guys walk in,' Ardell recalled. 'I wasn't sure they knew I was there, and I started getting a little uptight about it, so I decided to cough.' Ardell said he had considered rattling the toilet-paper dispenser as a means of announcing his presence, but decided against it out of concern that it would call attention to his wiping. 