The Sensex has slipped into the negative zone and is now down 23 points at 14,159.Dr.Reddy's has flared up 1.6% to Rs 824. ONGC, Tata Motors and Bajaj Auto have advanced over 1% each to Rs 906, Rs 960 and Rs 2,758, respectively.BHEL, Cipla, Reliance Communications, Hindalco, Wipro and HLL are the other prominent gainers.Satyam has shed 1.7% to Rs 480.