"DOCTOR AIN WAS recognized on the Omaha-Chicago flight. A biologist colleague from Pasadena came out of the toilet and saw Ain in an aisle seat. Five years before, this man had been jealous of Ain's huge grants. Now he nodded coldly and was surprised at the intensity of Ain's response. He almost turned back to speak, but he felt too tired; like nearly everyone, he was fighting the flu. The stewardess handing out coats after they landed remembered Ain too: A tall thin nondescript man with rusty hair. He held up the line staring at her; since he already had his raincoat with him she decided it was some kooky kind of pass and waved him on.