BEIJING, July 25 -- Beijing's air pollution index rose steadily this week at the same time that the city has tried to cut traffic volume in half. Readings Thursday and Friday were over 100 and considered unhealthy for children, seniors and those with allergies or asthma. The climb from a reading of 55 on Sunday to 110 on Friday -- despite six days of forcing Beijing motorists to drive on alternate days -- underscored the formidable challenge authorities face in trying to clear the air before athletes begin competing in the Aug. 8-24 Olympic Games. Already, one ... (more)