Both champions won by wide margins over the second-place finishers.
American Vincent Zhou and Japanese teenager Mana Kawabe are both in second place heading into the free skate.
“Everything is improving now and technically spiritual,” Uno said. “The most important thing I have practiced is the quadruple salchow.”
Though Chen won again this night, the margin was considerably closer. The pair were separated by just two points after the short program.
Chen holds a slight lead over his top rival, while Russia is in first place after the first day of competition.
Anna Shcherbakova captured her first world title, while Elizaveta Tuktamysheva and Alexandra Trusova finished second and third, respectively. Kaori Sakamoto placed sixth overall and Rika Kihira...