The Sensex at the Bombay Stock Exchange rose 52 points, or 0.3 per cent, to 17,801 in early trade, today, on fresh buying by funds, in line with firm Asian bourses.But later, the Sensex turned volatile, and after see-sawing between losses and gains, the 30-share index stood just 18 points, or 0.1 per cent in the positive zone, at 17,767 in afternoon deals, a short while ago.And stock markets in Japan, China, Singapore, Hong Kong, Indonesia, Taiwan and South Korea were up by between 0.3 percent and 0.8 percent, today, after Greece's parliament approved a new set of austerity measures required by international lenders in exchange for an emergency bailout.