Miners are holding back the FTSE 100, which is up by just a few points despite some well-received company updates.Worries that Japanese carmakers may have to suspend production at their plants in China following the earthquake disruption have sent copper prices lower. Kazakh copper group Kazakhmys, South Africa-focused platinum miner Lonmin and its FTSE 250-listed peer Aquarius Platinum are among the notable fallers.In company news, a 13-year tax wrangle between the US and the UK involving drugs giant AstraZeneca has been resolved, resulting in a substantially lower tax rate for Astra in the current financial year. As a consequence, Astra has lifted its core earnings per share guidance for fiscal 2011 to $6.90 - $7.20 from $6.45 - $6.75 previously. The shares are higher. Tullow Oil has found oil at the Teak-2 exploration well in the West Cape Three Points licence offshore Ghana. The Irish oil company, which has a 23% stake in the licence, discovered 27 metres of net hydrocarbon bearing Campanian and Turonian reservoirs at the well, drilled between the Jubilee field and Teak-1 discovery.Irn-Bru and Tizer maker AG Barr is fizzing today after saw profit on ordinary activities before tax and exceptional items increase by 13.3% to £31.6m in the 12 months to 29 January from £27.9m the year before. The company saw strong growth from all core brands in all channels.Growth in its business to business titles helped lift Daily Mail Group's underlying revenues by 5% over the past five months, though it was another tough period for regional paper arm Northcliffe.Shares in beleaguered care home owner Southern Cross slumped even lower on a weekend report it has told care home landlords it will not pay next quarter's rent.2010 was a year of strong recovery for Lamprell, the provider of engineering services to the international oil and gas industry, with the strength of the oil price contributing to unprecedented levels of enquiries. Underlying earnings before interest, tax, depreciation and amortisation (EBITDA) soared 90.3% to $78.4m. The shares are up by 8%.Exillon Energy is another riser. Its latest appraisal well on its West Siberia prospect has found more oil, this time on the northern extension of the East EWS I field.FTSE 100 - RisersResolution Ltd. (RSL) 287.60p +2.06%Cairn Energy (CNE) 456.30p +1.97%Burberry Group (BRBY) 1,137.00p +1.88%International Power (IPR) 311.40p +1.37%Old Mutual (OML) 134.70p +1.35%HSBC Holdings (HSBA) 655.80p +1.22%BAE Systems (BA.) 329.70p +1.17%Sage Group (SGE) 275.00p +1.10%Compass Group (CPG) 556.50p +1.09%Barclays (BARC) 293.00p +1.03%FTSE 100 - FallersKazakhmys (KAZ) 1,406.00p -2.83%Weir Group (WEIR) 1,697.00p -1.74%Lonmin (LMI) 1,661.00p -1.60%Fresnillo (FRES) 1,536.00p -1.54%Essar Energy (ESSR) 480.00p -1.36%Xstrata (XTA) 1,418.50p -1.18%Invensys (ISYS) 349.40p -1.05%Legal & General Group (LGEN) 116.00p -1.02%BP (BP.) 478.80p -0.98%Eurasian Natural Resources Corp. (ENRC) 926.00p -0.91%FTSE 250 - RisersLamprell (LAM) 337.50p +7.48%Dairy Crest Group (DCG) 372.10p +3.53%Exillon Energy (EXI) 410.00p +3.35%London & Stamford Property Ltd. (LSP) 128.50p +3.21%PartyGaming (PRTY) 198.70p +2.95%Ladbrokes (LAD) 133.90p +2.92%Chemring Group (CHG) 720.00p +2.86%AG Barr (BAG) 1,188.00p +2.86%Keller Group (KLR) 651.00p +2.84%Drax Group (DRX) 397.50p +2.61%FTSE 250 - FallersAquarius Platinum Ltd. (AQP) 349.30p -5.59%Kenmare Resources (KMR) 39.85p -4.44%Dixons Retail (DXNS) 16.43p -3.92%ITE Group (ITE) 242.00p -3.74%Sports Direct International (SPD) 191.40p -2.40%Daejan Holdings (DJAN) 2,585.00p -2.31%Brown (N.) Group (BWNG) 269.00p -2.04%Hochschild Mining (HOC) 644.50p -1.90%Redrow (RDW) 127.40p -1.70%Fenner (FENR) 358.00p -1.70%