Stocks were making moderate gains by Thursday lunchtime despite the Bank of England (BoE) refraining from further easing to boost the UK economy.At noon, the BoE revealed that policy-makers had voted to maintain interest rates at their record-low level of 0.5% (where they have been since March 2009) and keep its asset purchase programme unchanged at £375bn.However, it remains to be seen how tight the vote actually was as the proposal to increase asset purchases continues to gather support. Minutes of last month's meeting showed that while the majority voted to maintain the current level of quantitative easing (QE), even BoE Governor Mervyn King added his name to the list calling for more stimulus. Speaking before today's decision, Market Analyst Craig Erlam from Alpari said: "Last month's voting suggests we're going to see a central bank more focused on growth than inflation in the near future. The voting in today's meeting will probably be neck and neck with those against more QE edging it by five votes to four."The European Central Bank will also reveal its policy decision this afternoon and is widely expected to stand pat, ignoring recent calls for a rate cut to counter a subdued economy and a strong currency. However, the following press conference with Bank President Mario Draghi could be used to hint at future loosening and so will be closely watched.Erlam said: "I still expect to see a rate cut in the coming months, however we may have to see inflation fall sufficiently below 2.0% target level before certain policy makers climb on board."In other central-bank news, the Bank of Japan voted to keep interest rates and its asset purchase programme unchanged, a decision that was widely expected given the Bank's recent aggressive easing.FTSE 100: Aviva plummets; Aggreko soarsInsurance giant Aviva was forced to slash to dividend after swinging into the red in 2012, after taking a 3.3bn-pound write-down on a disposal in the US. Aviva also said that its overall situation does not warrant bonuses for executive directors for 2012 or pay rises for 2013. Shares dropped sharply early on.Panmure Gordon cut its rating for Aviva from 'buy' to 'hold' today, saying that while the dividend cut will remove some uncertainty, "the market will rightly be disappointed".Heading the other way was temporary power and temperature control provider Aggreko which rocketed after posting a strong performance in 2012 with trading profit up 13% last year. Investec upgraded the stock from 'hold' to 'buy' this morning.IMI, the engineering firm, rose strongly after boasting a "resilient" set of results in 2012 and unveiling a share buy-back programme of up to £175m over the next 12 months.Insurance provider Standard Life slipped despite revealing a special dividend worth £302m after delivering substantial growth in profits in 2012.British asset management firm Schroders was higher after saying that assets under management reached record levels in spite of choppy markets and falling profits.FTSE 250: National Express dropsTransport group National Express was a heavy faller after reports yesterday said that US investor Elliot Advisors plans to sell over 50m worth of shares, equal to a 9.9% stake.Engineering firm Spirax-Sarco was in demand after proposing a special dividend of 100p per share in addition to an 8.0% rise in the full-year payout, after a 2.0% rise in revenue in 2012.FTSE 100 - RisersAggreko (AGK) 2,015.00p +14.62%IMI (IMI) 1,329.00p +5.31%Reckitt Benckiser Group (RB.) 4,628.00p +2.48%Rio Tinto (RIO) 3,450.00p +2.40%Barclays (BARC) 308.95p +2.25%Meggitt (MGGT) 486.60p +2.21%CRH (CRH) 1,481.00p +2.14%Admiral Group (ADM) 1,359.00p +1.87%Unilever (ULVR) 2,731.00p +1.83%Schroders (SDR) 2,070.00p +1.67%FTSE 100 - FallersAviva (AV.) 314.20p -12.67%Melrose Industries (MRO) 259.70p -2.77%British Sky Broadcasting Group (BSY) 872.50p -1.80%Lloyds Banking Group (LLOY) 50.24p -1.53%Morrison (Wm) Supermarkets (MRW) 260.00p -1.22%Vodafone Group (VOD) 178.10p -1.06%TUI Travel (TT.) 308.30p -0.90%ARM Holdings (ARM) 954.50p -0.88%Carnival (CCL) 2,510.00p -0.87%Old Mutual (OML) 208.30p -0.86%FTSE 250 - RisersRegus (RGU) 152.30p +6.13%Spirax-Sarco Engineering (SPX) 2,645.00p +5.67%RIT Capital Partners (RCP) 1,234.00p +5.29%Cobham (COB) 238.20p +3.93%Betfair Group (BET) 714.50p +3.85%SEGRO (SGRO) 267.80p +3.68%Bumi (BUMI) 329.90p +3.42%Elementis (ELM) 254.40p +3.00%Big Yellow Group (BYG) 388.00p +2.81%Ashtead Group (AHT) 591.00p +2.78%FTSE 250 - FallersNational Express Group (NEX) 205.10p -10.83%Petropavlovsk (POG) 250.30p -8.82%Balfour Beatty (BBY) 274.50p -4.36%Heritage Oil (HOIL) 189.80p -3.56%Smith (DS) (SMDS) 233.60p -2.87%Playtech Ltd. (PTEC) 545.50p -2.68%Ladbrokes (LAD) 228.10p -2.65%Dialight (DIA) 1,310.00p -2.60%Hunting (HTG) 907.50p -2.58%IP Group (IPO) 136.40p -2.22%BC