Sports fashion wear retailer JD Sports Fashion jumped after confirming press speculation that it is in talks to buy assets of struggling camping equipment retailer Blacks Leisure and that talks are at an advanced stage. Shares in Blacks Leisure were suspended on 6 January as the company enters an administration process. Housebuilder Persimmon also rose after saying it expects a 50% increase in underlying pre-tax profit after it introduced a raft of measures to combat the sluggish UK housing market. An improvement in underlying operating profit and a reduction in net finance costs will result in full year underlying pre-tax profit being towards the top end of analysts' expectations, the group said. Balfour Beatty, the international infrastructure group, dropped despite having won a 10-year deal to run services and facilities for the future Queen Elizabeth Olympic Park in East London. The contract value is £50m over the next ten years, although further scope extensions under discussion between Balfour Beatty WorkPlace and the Olympic Park Legacy company may see the long-term value of the wider Olympic Park work grow significantly beyond the initial operational phase, the firm said. EnQuest, the North Sea-focused oil company, was heading higher after spending up to $90m for a 20% interest in the Kraken oil discovery in the East Shetland basin. The transaction will see EnQuest buy two subsidiaries from oil and gas exploration and devlopment outfit Canamens Energy: Canamens Energy North Sea and Canamens UK 814 and 815.Also rising electrical components manufacturer Laird said trading in the final quarter has followed the same trends as the third and is confident of delivering earnings in line with company forecasts. FTSE 250 - RisersJD Sports Fashion (JD.) 702.00p +6.36%Carpetright (CPR) 540.00p +5.26%Persimmon (PSN) 502.00p +4.37%Senior (SNR) 184.80p +4.29%Bovis Homes Group (BVS) 424.90p +4.14%Telecity Group (TCY) 655.00p +3.89%Unite Group (UTG) 169.20p +3.17%Rentokil Initial (RTO) 66.65p +3.17%Howden Joinery Group (HWDN) 105.50p +3.03%EnQuest (ENQ) 106.70p +2.60%FTSE 250 - FallersHeritage Oil (HOIL) 182.20p -5.84%Home Retail Group (HOME) 87.65p -4.93%Debenhams (DEB) 56.65p -3.25%Henderson Group (HGG) 97.50p -3.18%Jupiter Fund Management (JUP) 190.00p -3.06%Ocado Group (OCDO) 56.40p -2.84%Cable & Wireless Worldwide (CW.) 17.04p -2.46%Perform Group (PER) 205.10p -2.33%Morgan Crucible Co (MGCR) 270.50p -2.28%Regus (RGU) 84.25p -2.21%NR