The top share index spent the morning spinning its wheels with most of the excitement taking place among the mid-cap stocks.Last night, the Federal Reserve's April Beige Book survey encouraged the maintenance of the status quo. The Fed's survey revealed that overall activity "continued to expand at a modest to moderate pace" in February and March. Price inflation has been "modest" but fuel prices have caused some concern, the report said. In other news, the World Bank has cut its forecast for Chinese gross domestic product (GDP) from 8.4% to 8.2%, a 13-year low. "With the economy slowing in the near term, the policy challenge is to ensure that this continues in a gradual fashion," the World Bank said. "Sufficient policy space exists to facilitate an orderly adjustment and respond to downside risks if they were to materialise."Shell slides on Gulf of Mexico slickAnglo-Dutch oil group Royal Dutch Shell fell sharply on the back of reports of a 10-by-one mile oil sheen near to one of its platforms in the Gulf of Mexico. While no one knows where the oil came from as of yet, the company has sent a vessel to investigate. Sector peer BP was also out of favour.Sticking with the blue-chips, engineering giant GKN was a high riser after an upgrade from Credit Suisse which upped its rating from neutral to outperform. Elsewhere in the engineering sector Rolls-Royce was buoyed by winning a turbine contract from the US navy.Temporary power and temperature control solutions group Aggreko jumped early on after reporting 21% growth in underlying group revenue in the first quarter. "We continue to believe that we will deliver another year of good growth in 2012," the group said. Emerging markets asset manager Ashmore Group saw assets under management (AuM) recover strongly in its third quarter, following a fall in the first half. AuM rose 9.1% in the period, compared with the 9% fall in the first six months of the year. Purple HaysRecruitment firm Hays surged after saying that full-year operating profit is likely to come in at the top end of market expectations following a strong third quarter. Impressive growth in net fees overseas offset a slight decline in the UK and Ireland.Egyptian gold miner Centamin rose strongly after seeing total production grow 9% in the first quarter despite strike activity during the period. Sector peer Petropavlovsk pulled out of the tail-spin it has been in since the start of February after the company announced a sharp increase in gold production in the first quarter.Residential property owner Grainger was also in demand after saying that completed sales from its UK and German portfolios in the first half were ahead of the prior year.Retailers in need of therapyJD Sports Fashion, which sells sportswear for people who are not necessarily interested in participating in sporting activity, headed backwards after it said its margins are under pressure as even fashion-conscious consumers are looking for bargain prices on designer-labelled products.In contrast, baby and toddler products seller Mothercare was wanted, despite the company binning its dividend to save cash for its three-year turnaround programme, which has been given the support of its banks. The company intends to close another 111 UK stores as it continues its withdrawal from the high streets of Britain. Mothercare plans to reshape its UK operations around a profitable core of 200 stores, comprising 95 out of town stores and 105 High Street stores. Of these, 173 stores will carry the Mothercare brand and 27 are Early Learning Centres.Another company reducing its High Street presence is pubs group Punch Taverns. The group's shares took a leathering as it announced underlying earnings before interest, tax, depreciation and amortisation sank to £128.3m in the 28 weeks to March 3rd from £138.6m in the corresponding period of the previous year. Like-for-like income in Punch's core estate - i.e. the best performing pubs - fell 2.1% from the corresponding six month period a year earlier.FTSE 100 - RisersGKN (GKN) 199.90p +4.39%Johnson Matthey (JMAT) 2,343.00p +3.31%Rio Tinto (RIO) 3,444.00p +3.22%Fresnillo (FRES) 1,616.00p +3.06%Eurasian Natural Resources Corp. (ENRC) 585.00p +2.63%Aggreko (AGK) 2,215.00p +2.59%Meggitt (MGGT) 404.70p +2.51%ITV (ITV) 85.10p +2.41%Croda International (CRDA) 2,118.00p +2.37%Wolseley (WOS) 2,342.00p +2.09%FTSE 100 - FallersRoyal Dutch Shell 'A' (RDSA) 2,050.00p -4.25%Royal Dutch Shell 'B' (RDSB) 2,096.50p -4.05%Man Group (EMG) 113.30p -2.07%BP (BP.) 435.25p -2.03%Resolution Ltd. (RSL) 246.70p -1.56%Aviva (AV.) 309.40p -1.02%Evraz (EVR) 349.90p -0.93%Smith & Nephew (SN.) 610.50p -0.65%Admiral Group (ADM) 1,196.00p -0.58%Legal & General Group (LGEN) 123.70p -0.56%FTSE 250 - RisersHays (HAS) 89.90p +10.65%Centamin (DI) (CEY) 67.45p +6.72%Morgan Crucible Co (MGCR) 328.30p +4.85%New World Resources A Shares (NWR) 427.50p +4.17%Ashtead Group (AHT) 246.10p +3.58%Fenner (FENR) 438.10p +3.33%UBM (UBM) 608.00p +3.23%Sports Direct International (SPD) 282.10p +3.22%Ferrexpo (FXPO) 290.50p +3.05%FTSE 250 - FallersAfrican Barrick Gold (ABG) 356.80p -3.75%JD Sports Fashion (JD.) 771.50p -3.44%Supergroup (SGP) 595.50p -1.89%JPMorgan Russian Securities (JRS) 550.50p -1.70%Dairy Crest Group (DCG) 313.30p -1.66%Dixons Retail (DXNS) 17.51p -1.63%Halfords Group (HFD) 290.60p -1.59%JH