- Chinese PMI falls to seven-month low- Fed extends 'the twist', lowers GDP forecast- Miners provide a drag in LondonDisappointing economic data from China and a downward revision to US growth dented the Footsie in early trading on Thursday, with mining stocks bearing the brunt of the sell-off.The Chinese manufacturing sector purchasing managers' index for the month of June compiled by Markit fell from 48.4 to 48.1 in June, a seven-month low. Many observers believe that the Asian powerhouse will bottom-out in the current quarter. Commenting on the Flash China Manufacturing PMI, Hongbin Qu, chief economist, China & Co-Head of Asian Economic Research at HSBC said: "China's manufacturing sector continued to slow in June, though the pace of slowdown seems to be slowing. With external headwinds remaining strong, exports are likely to decelerate in the coming months. The sharp fall of prices and moderation of new orders suggest weak domestic demand, posing destocking pressures for Chinese manufacturers. All will likely weigh on the jobs market. As such, we expect more decisive policy stimulus to reverse the growth slowdown." In other news, the keenly-awaited policy decision in the US last night failed to boost markets as was hoped, after the Federal Reserve also downgraded its growth expectations for the world's largest economy. Fed Chairman Ben Bernanke said that the European crisis was "slowing US economic growth." While the Federal Open Market Committee decided to extend its 'Operation Twist' programme, which involving the sale of short-term debt in exchange for long-term securities with the intention of flattening the interest rate curve, the central bank said it expects US GDP to grow by 1.9-2.4% in 2012, down from earlier predictions of a 2.4-2.9% expansion. In Eurozone news, there were rumours that German Chancellor Angela Merkel has said that bond purchases by the European bail-out funds are a possibility.Company movements: Miners tank after China dataConcerns over the Chinese economy pressured sharp falls in the mining sector this morning as investors expressed worries about slowing demand. Vedanta, Kazakhmys, Xstrata, Glencore, Rio Tinto, BHP Billiton, Antofagasta, Anglo American and Polymetal dominated the fallers list.With investors fleeing from these 'riskier' assets, defensive sectors were in demand with pharmaceuticals group GlaxoSmithKline and AstraZeneca, and tobacco giant BATS on the rise.Water company Severn Trent rose after announcing the launch of a 10-year sterling bond with a coupon linked to the retail prices index. The bonds will pay interest semi-annually at a real rate of interest of 1.3% per annum adjusted to take account of changes in the level of the UK Retail Prices Index (RPI). The bonds, to be issued at £100 a throw, could, however, end up paying less than 1.3% per year if the UK experiences deflation.FTSE 250 construction equipment leasing firm Ashtead Group jumped early on after reporting record profits as tight cost control and strong demand in the US helped the firm beat analyst expectations. Bid talks which got the market excited on Wednesday about Invensys, the maker of rail signalling and industrial automation systems, have hit the buffers already causing shares to pull back. In response to press speculation about an approach from Emerson Electric for some of the company'sassets, news of which leaked out on Wednesday, Invensys said talks with Emerson are no longer taking place. FTSE 100 - RisersGlaxoSmithKline (GSK) 1,479.50p +1.06%Reckitt Benckiser Group (RB.) 3,400.00p +0.98%Unilever (ULVR) 2,077.00p +0.73%Associated British Foods (ABF) 1,242.00p +0.65%Aggreko (AGK) 2,112.00p +0.62%AstraZeneca (AZN) 2,783.00p +0.60%Pearson (PSON) 1,216.00p +0.50%British American Tobacco (BATS) 3,233.50p +0.42%Shire Plc (SHP) 1,952.00p +0.41%Compass Group (CPG) 655.00p +0.38%FTSE 100 - FallersVedanta Resources (VED) 934.00p -4.50%Kazakhmys (KAZ) 721.50p -4.50%Xstrata (XTA) 839.70p -3.49%Glencore International (GLEN) 321.70p -3.47%Rio Tinto (RIO) 2,998.00p -3.13%Weir Group (WEIR) 1,512.00p -2.95%Antofagasta (ANTO) 1,090.00p -2.85%Anglo American (AAL) 2,152.50p -2.82%BHP Billiton (BLT) 1,824.50p -2.72%Eurasian Natural Resources Corp. (ENRC) 425.90p -2.34%FTSE 250 - RisersAshtead Group (AHT) 267.80p +6.95%Stobart Group Ltd. (STOB) 121.70p +2.87%Interserve (IRV) 304.20p +1.47%Micro Focus International (MCRO) 458.40p +1.42%Rank Group (RNK) 122.40p +1.41%Barr (A.G.) (BAG) 435.00p +1.16%Bank of Georgia Holdings (BGEO) 1,011.00p +1.10%Rathbone Brothers (RAT) 1,213.00p +1.08%Aberforth Smaller Companies Trust (ASL) 568.00p +0.89%Dechra Pharmaceuticals (DPH) 487.20p +0.87%FTSE 250 - FallersInvensys (ISYS) 214.60p -16.50%Aquarius Platinum Ltd. (AQP) 54.00p -9.55%Ferrexpo (FXPO) 211.50p -4.94%Afren (AFR) 105.00p -4.20%Man Group (EMG) 74.65p -4.11%Heritage Oil (HOIL) 124.70p -4.08%Bellway (BWY) 775.00p -4.02%Home Retail Group (HOME) 83.60p -3.91%Centamin (DI) (CEY) 66.50p -3.76%Petropavlovsk (POG) 465.70p -3.48%BC