A doll in mask is seen at a rally appealing for a reduction of motor vehicles' use at the Place du Chatelet in Paris, capital of France, on Dec. 17, 2016. A new peak in air pollution forced Paris authorities to restrict traffic in the capital Dec. 16-17. Vehicles, heating systems and wood burning have caused smog spike, the country's worst and longest pollution in a decade. (Xinhua/Chen Yichen)