The BSE benchmark Sensex, which gained over 90 points in opening trade, stood at 190 points in the positive territory at 15,929 in afternoon deals, a short while ago.The 30-share Sensex rose by 90 points, or 0.57 per cent, to 15,829 in opening trade, on the back of selective buying in blue-chips amid covering up of pending short positions by speculators. The Sensex had lost 75 points in the previous session on Friday.In Asia, Japan's Nikkei Index rose by 1.37 per cent in morning trade today, while the US Dow Jones Industrial Average ended 1.02 per cent higher in Friday trade.