The Sensex at the Bombay Stock Exchange rose 66 points, or 0.3 per cent, to 19,383 in opening trade, this morning, on fresh buying by funds and retail investors, amid mostly rising regional bourses. But later, the Sensex turned volatile, and after swinging between gains and losses, stood 49 points, or 0.3 percent in positive territory, at 19,366 a short while ago. The Sensex had lost 326 points in the previous two trading sessions.Stock markets in Japan, China, Singapore, Indonesia and Hong Kong had gained between 0.1 percent and 1.7 percent, today, on speculation that the next Bank of Japan governor will deploy aggressive monetary easing.