High-tech tool manufacturer Oxford Instruments was rising high after it said first half pre-tax profit fell to £12.5m from £13.2m the year before but it sees an improved second half.The group, which makes and supplies tools and systems, said revenue surged over 40% in a 'robust' market environment, as it introduced new products. Shares in coal-fired power station operator Drax also rose after the company said its full year results would be towards the top of market forecasts.The firm said this was based on a range of market forecasts of between £292m to £331m for earnings before interest, tax depreciation and amortisation and of between 43 pence to 54 pence for underlying earnings per share. Meanwhile, the announcement of a new chief executive at embattled telecoms firm Cable & Wireless Worldwide wasn't enough to stop shares plunging as it announced a big fall in profits and the suspension of all dividend payments starting next financial year.The company posted pre-tax profits of £35m in the first half, down from £64m in 2010.Dixons was also falling after Credit Suisse cut its target price for the Currys and PC World owner ahead of the firm's interim results next week.To reflect "weak Southern European trends", the broker cuts its current year and next year pre-tax profit estimates by 10% and 7%, respectively. As such, the target price - based on a forward earnings multiple of 10 - is cut from 27p to 25p. Following suit, Aveva, the Cambridge based engineering information technology company, was falling despite seeing revenues rise 9% in the six months to the end of September compared to the same period of 2010. FTSE 250 - RisersOxford Instruments (OXIG) 936.00p +11.10%Micro Focus International Plc (MCRO) 364.50p +4.41%Elementis (ELM) 144.90p +3.87%Supergroup (SGP) 684.50p +3.87%Exillon Energy (EXI) 308.60p +3.42%Drax Group (DRX) 572.50p +3.34%Provident Financial (PFG) 1,043.00p +2.25%Afren (AFR) 88.35p +2.20%Pennon Group (PNN) 725.50p +1.90%Britvic (BVIC) 335.70p +1.73%FTSE 250 - FallersCable & Wireless Worldwide (CW.) 24.98p -17.28%Premier Foods (PFD) 5.05p -12.02%Dixons Retail (DXNS) 11.31p -5.12%SIG (SHI) 88.25p -4.75%Renishaw (RSW) 908.50p -4.42%Talvivaara Mining Company (TALV) 196.90p -4.18%Misys (MSY) 280.20p -3.91%London Stock Exchange Group (LSE) 830.50p -3.82%Aveva Group (AVV) 1,564.00p -3.58%Sports Direct International (SPD) 230.80p -3.43%NR