Retailer Topps Tiles (TPT), whose fortunes are correlated to housing transactions and economic recovery, rises 3.75% to 124.5p on impressive interim figures. The UK's biggest tile specialist reports 10.2% like-for-like sales growth and taxable profits up 70% to £8 million for the half to March and flags a good start to the second half.

Hefty investment will squeeze Vodafone (VOD) earnings in 2015, the group spells out today, sending the shares spinning 3.8% lower 208.9p. The news comes as the world's number two mobile network operator reports impairments of £6.6 billion due to fierce competition and regulatory changes in Europe. We'll have more on this on the Shares website later.

High Street fashion-to-foods giant Marks & Spencer (MKS) is marked 2.4% lower to 440.1p despite full-year results coming in marginally ahead of consensus, showing a 4% taxable profits drop to £623 million. UK like-for-like sales are up 0.2% with 1.7% growth in the flourishing food business compensating for a 1.4% decline in General Merchandise, though CEO Marc Bolland insists clothing sales continue their improving trend.

Horticulture products producer William Sinclair (SNCL:AIM) slumps almost 30% to 78.5p on yet another profits warning. This year's better weather has failed to provide a sales boost and the growing media specialist now expects to report a 'significant' annual loss for the year and will also pass the interim dividend.

Microcap media business UBC Media (UBC:AIM) collapses 50% 3.12p after having its suspension lifted and unveiling an acquisition, £6 million cash call and a name change to 7Digital. This is part of a strategy rethink aimed at moving the company into fast-growing parts of the content supply industry.

Convenience food maker Greencore (GNC) fattens up 5.9% to 261.6p on very strong half-year results, as foreshadowed by Shares recently. Driven by its 'food on the go' businesses in the UK and US, sales grew 8.2% to £619.8 million and Greencore cooked up a 20.5% taxable profits gain to £30.7 million.

Concerns over the underlying health of financial software supplier First Derivatives (FDP:AIM) drag on the shares despite improved full year results. The stock falls 6.5% to £10.00 despite revenues rising 24% to £70 million, producing a 19% earnings before interest, tax, depreciation and amortisation (ebitda) improvement. Overseas losses and low cashflow continue to concern investors.

Aerospace and defence company Cobham (COB) ticks up 0.9% to 315p as it moves to buy US rival Aeroflex for $894.6 million. Alongside the proposed transaction it announces plans to raise £195 million through a placing. Aeroflex is a leading supplier of radio frequency (RF) and microwave integrated circuits and components, and 70% of its sales are to commercial aerospace markets - so the deal should accelerate Cobham's strategy of switching to this space from its previous bias towards pressured defence markets.

African oil and gas firm Afren (AFR) falls 4.8% to 146.7p on a 38% year-on-year drop in first quarter operating cashflow to $169.1 million. The slippage reflects the reduction in its working interest in the Ebok field in Nigeria from 100% to 50% post the recovery of costs, an issue discussed in Shares last November.

Fellow Nigerian operator Lekoil (LEK:AIM) falls 4.4% to 66p after the unveiling of a $78 million deal to acquire the producing Otakikpo field in the Niger Delta and an accompanying placing to raise around $34 million. Westhouse puts its add recommendation under review and comments: 'Our only misgiving is that the Otakikpo field is in shallow waters in the eastern part of the Niger Delta and it appears it will seek to use onshore infrastructure to commercialise the hydrocarbons.'

Instrument-maker Scientific Digital Imaging (SDI:AIM) tanks 23.3% to 16p on a profits warning due to competition hitting demand for its Syngene range. Any profit it reports at its finals in July will be the result of it welding the cost-cutting axe.

Testing kit maker EKF Diagnostics (EKF) rises 5.1% to 25.7p on winning a contract to provide a range of health tests for women in the US, such as screening for chlamydia and herpes. The Cardiff-based company expects to provide around 1,000 tests a month and to be paid between $90 and $450 million a sample.

A strong performance by FTSE 250 biotech BTG's (BTG) interventional medicine business fails to prevent the shares dropping 1.7% to 516p.

The shipping industry falls under the spotlight as ACM Shipping Group (ACMG:AIM) seals its takeover by Braemar Shipping Services (BMS). ACM investors will get two new shares in the enlarged company plus 250p cash per share, pushing its stock 5.5% higher to 253p. In contrast, Braemar slumps 5% to 513p.

Speciality chemicals company Victrex (VCT) climbs 2.4% to £17.39 as interim results show a 14% hike in sales and a 7% increase in profit before tax.

Flavours, fragrances and consumer goods specialist Treatt (TET) adds 2.6% to 158.5p on encouraging half-year results that show an 11% rise in revenues and 39% jump in adjusted pre-tax profit.

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Issue Date: 20 May 2014