Continued buoyancy in the market backed by robust FII inflows saw the Sensex open yet again with a positive gap. The index after opening at 13,501 (up 32 points) scaled to higher level backed by aggressive buying in banking and cement stocks.The index touched a new all-time intra-day high of 13,588 in mid-noon trades today. However, profit taking mainly in Infosys saw the index pare gains and slip into red to a low of 13,459, down 129 points from the day's high.The Sensex, however, soon bounced back into the positive zone, but eventually finished with a marginal gain of 37 points at 13,506.