PYEONGCHANG/MOSCOW (Reuters) - Russian Olympic curler Alexander Krushelnitsky has been found guilty of an anti-doping violation after testing positive for the banned substance meldonium, the Court of Arbitration for Sport (CAS) said on Thursday. CAS said the Olympic Athletes from Russia (OAR) mixed doubles curling team, who won bronze at the Winter Games in Pyeongchang, had been disqualified from the competition over the violation.