With UK sales remaining stubbornly flat, Marks and Spencer stitched together a more encouraging fourth-quarter result, but was nonetheless sat firmly in the bottom spot on the FTSE today. The group said second-half general merchandise gross margin will be down against the previous year, in line with the first half, as the group looks to compete with the high levels of promotion from its rivals. As a result, full-year UK gross margin is expected to be down around 20 basis points, compared to a flat outcome previously expected by the market. Broker N+1 Singer said the lack of visible revenue improvements was continuing to test investor resolve, but that these numbers provided some small encouragement, enough to maintain a 'buy' recommendation.Antofagasta declined after UBS reduced its rating on the stock from 'neutral' to 'sell'. Broker Cantor Fitzgerald has maintained its 'sell' stance on Royal Mail Group (RMG), the day after UK postal regulator Ofcom confirmed it will investigate the company's proposals on access charges. "In our view," wrote analyst Robin Byde, "this is potentially a nasty battle between Ofcom, RMG and TNT Post on access mail, direct delivery services etc."ARM Holdings retreated from its recent surge which came on the back of gains in the tech-sector Stateside earlier in the week. Travis Perkins was also a notable faller, bucking the trend of its sector, which rose amid signs of continued robust growth in the UK housing market. Building products giant CRH was a big riser following the data, released by both the Council of Mortgage Lenders and the Royal Institution of Chartered Surveyors. Real estate company Land Securities was also driven higher. Associated British Foods was climbing strongly after earlier in the week being hit by a rival's profit warning on sugar. However, the situation is looking more positive after Morgan Stanley analysts said it continued to believe that the group's Primark business "will be the key driver in 2014/15, delivering 8% plus top-line growth and 12%-15% earnings per share growth from 2015, and we remain firmly overweight". Imperial Tobacco was also a strong riser. The company today released its Just Additive Free cigarettes under the JPS brand. FTSE 100 - RisersAssociated British Foods (ABF) 2,672.00p +2.65%Land Securities Group (LAND) 1,039.00p +2.26%Imperial Tobacco Group (IMT) 2,469.00p +2.19%Shire Plc (SHP) 2,968.00p +2.13%Randgold Resources Ltd. (RRS) 4,710.00p +1.79%CRH (CRH) 1,777.00p +1.60%Compass Group (CPG) 923.50p +1.54%HSBC Holdings (HSBA) 620.90p +1.34%AstraZeneca (AZN) 3,856.50p +1.18%Next (NXT) 6,535.00p +1.08%FTSE 100 - FallersMarks & Spencer Group (MKS) 441.40p -3.20%Antofagasta (ANTO) 828.50p -2.30%Royal Mail (RMG) 505.00p -1.94%Morrison (Wm) Supermarkets (MRW) 199.50p -1.19%Travis Perkins (TPK) 1,829.00p -1.19%Tullow Oil (TLW) 840.00p -1.18%SSE (SSE) 1,470.00p -1.08%ARM Holdings (ARM) 1,018.00p -1.07%Centrica (CNA) 334.20p -1.01%G4S (GFS) 247.00p -1.00%NR