[1/4] Participants take part in the Beijing Marathon, at Tiananmen Square in Beijing, China October 29, 2023. REUTERS/Tingshu Wang Acquire Licensing Rights BEIJING, Oct 29 (Reuters) - Runners undeterred by thick smog engulfing the Chinese capital ran the Beijing Marathon maskless on Sunday, many wearing shorts in one of the warmest Octobers on record. Despite a greyish brown smog settling, some 30,000 marathoners set off at 7:30 a.m. (2330 GMT) from Tiananmen Square on the route through four districts of the Chinese capital over 42.195 km (26.2 miles). Beijing was the fourth most-polluted major city in the world on Sunday,...