* Senior advisers asked to call or meet private banking clients. : SINGAPORE/HONG KONG (Reuters) - UBS has asked its senior client advisers to call or even meet private banking customers from China who have raised concerns about a comment from one of the bank’s economists that some people interpreted a racist slur, sources told Reuters. A reference to Chinese pigs was made in an inflation analysis podcast by UBS global chief economist Paul Donovan, who has since been put on a leave of absence as the bank reviews the matter. The podcast has been taken down.