An overnight rally on Wall Street and gains across Asian markets puts UK investors in positive mood in early trading on Wednesday, pushing London share prices higher. The benchmark FTSE 100 index is trading 40 points up, or roughly 0.6%, at 6,660 thanks to a swathe opf positive corporate announcements, although mid cap progress capped, the FTSE 250 nudging just 24 points higher, 0.15%, to 16,151.

Publisher of the Financial Times and education products specialist Pearson (PSON) heads the Footsie leader board on Wednesday, up 4.5% to £12.92. The rally is sparked by confirmation of guidance for 2014 and points to growth in 2015. Today's big rise after a reassuring rather than 'knock the lights out' statement can be seen in the context of the company's heavy fourth quarter weighting and the inclusion in last January's update of a profit warning.

Going the other way is product tester Intertek (ITRK), its 5.4% decline to £22.56 leading the Footsie fallers, closely followed by and Sports Direct (SPD). The pile 'en high, sell 'em cheap sporting retailer slumps 4.4% to 727p is down as founder Mike Ashley flogs another 15.4 million stack of stock, or 2.57% of the company.

Nigerian oil firm Afren (AFR) falls 10.9% to 23p on news late Tuesday it is reviewing its 'capital structure, liquidity and funding requirements' and looking at its cost base and spending plans for 2015 given the recent rapid plunge in oil prices. On Monday it extended a ‘put up or shut up’ deadline for potential bidder Seplat (SEPL) to make an offer until 30 January.

General merchandise discounter Poundland (PLND) cheapens 10p to 353.2p on news third quarter growth slowed due to the later than anticipated opening dates of new stores. Nevertheless, the single price retailer, a running Shares Play of the Week, reports another good quarter with sales (excluding Spain) up 9.8%, buoyed by record Christmas trading.

Beverages behemoth SABMiller (SAB) froths 76.5p (2.3%) higher to £34.20 on a well-received third quarter update. The running Play of the Week highlights steady sales growth, driven by its Latin America and Africa businesses, although ongoing lager weakness and tough trading in China constrained overall progress.

Merged electricals-to-telecommunications retail titan Dixons Carphone (DC.) sparks up 2.9p to 445.1p. News of strong Christmas trading, with group like-for-like sales up by a better-than-expected 7%, stokes upgrades to full-year profit guidance.

Specialist retailer Pets At Home (PETS), one of our key trades for 2015, skips 2% higher to 207p on a pleasing third quarter and Christmas trading update, revealing 4.1% growth in like-for-like sales for the 12 weeks to 1 January.

Domino's Pizza (DOM) falls 3.6% to 637.5p on news chief financial officer Sean Wilkins has resigned. The pizza delivery firm says trading has been positive in the final quarter and it expects profit before tax to be in line with, or marginally ahead of, consensus forecasts of £54.2 million.

Pub chain JD Wetherspoon (JDW) slips 2.6% to 798p after like-for-like sales slow from 6.3% in the first quarter to 2.8% in the second quarter. This is blamed on tough comparisons due to the extension of food trading hours in autumn 2013 but also heightened supermarket competition. Numis cuts its 2015 pre-tax profit forecast from £84.7 million to £81.2 million and its price target from 950p to 875p.

An upbeat third quarter update from FirstGroup (FGP) drives a 3.2% share price rise, to 105.3p. The trains-to-buses group expects to meet forecasts for the current financial year after strong third-quarter performances from its rail operations in Britain and its shuttle bus business in the United States.

Among smaller companies, the slump in the copper price has made Weatherly International's (WTI:AIM) operations in Namibia uneconomic, triggering a 22.7% drop in the share price to 1.7p. We look at the situation in more detail here.

Publishing Technology (PTO:AIM) crashes 10% to 160p as it reveals overly bullish revenue recognition that sparks a profit warning. This will come as no surprise to Shares readers, we flagged the company's challenges in October.

ID security software supplier Intercede (IGP:AIM) collapses by more than 15% to 112.5p as it cuts growth expectations for the full year. Contracts shifting to the right are to blame, with the company now anticipating revenues at a similar level or slightly lower than last year, when they grew 45% to £9.8 million, sparking overall losses of around £1 million.

The market deals a hrash hand to contract electronics engineer Stadium (SDM:AIM) as the company unveils manufacturing expansion in China to meet growth opportunities. But the two to three year payback on a less than £1 million investment goes down badly, knocking the shares nearly 4% lower to 111p.

Reference checker ClearStar (CLST:AIM), one of Shares 15 for 2015 plays, jumps 9% to 73p as the US-based company confirms forecast-beating 2014 results. The company also confirms further investment in expansion across new geographies as demand for its services grow

Crowd sourcing platform Blur (BLUR:AIM) leaps more than 12% to 58p as it reveals the start of a $3 million enterprise project by a global fast-moving consumer goods company. 'This project is significant because it demonstrates that large enterprises are increasingly recognising the advantages of using the Blur exchange,' says CEO Philip Letts.

In-line trading confirmation continues the positive market view over gaming terminals technology supplier Quixant (QXT:AIM), the shares nudging 2.4% higher to 151p, three-times the price of its IPO in May 2013 at 46p.

Kurdistan oil producer and constituent of Shares '15 for 2015' portfolio Genel Energy (GENL) slips 2.2% to 650.7p  as it reveals an exploration write-off of $480 million and reduces revenue guidance for 2015 from between $500 million and $600 million to a maximum of $400 million to reflect lower oil prices. The modest sell-off reflects the fact that neither of these announcements are a big surprise.

Obesity and diabetes-focused life sciences company OptiBiotix (OPTI:AIM) gains 6.7% to 23.7p on forming a joint venture with Dutch outfit Nizo Food Research to make metabolism-boosting dairy products, such as yogurt.

Live biotherapeutics-focused drug developer 4D Pharma (DDDD:AIM) falls 5.4% to 435p as the company comes cap in hand to investors for further funding. The latest cash call raises £34.7 million from a placing to invest in its pipeline and development capabilities.

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Issue Date: 21 Jan 2015