A profit warning from BATM Advanced Communications (BVC) has triggered a 25% fall in the share price to 15p. The medical laboratory-to-telecoms technology specialist has suffered from a delay in receiving parts and tighter credit control. The latter has seen BATM demand stricter payment conditions before it will send out goods, resulting in the group stopping shipments to several major customers in May and thus hurting revenue.

Homeserve (HSV) jumped 7.7% to 264.4p on speculation that an investigation into alleged mis-selling by the City regulator is near conclusion, which could lead to takeover interest from private equity.

Russian silver and gold producer Polymetal (POLY) added 2p to 677.5p on high-quality drill results from the FTSE 100 constituent's Mamin project. The exploration details focus on a new area outside of the existing proven pit, which bodes well for increasing the size of the project.

Barclays (BARC) dipped 2% to 309.95p after a large slug of its shares were understood to have been placed in the market at a discount to yesterday's price.

Cigarette filters-to-packaging group Filtrona (FLTR) nudged ahead 0.6% to 702p after announcing plans to rebrand as Essentra. The FTSE 250 group will change its epic code from FLTR to ESNT from 26 June.

Chemicals and precious metals giant Johnson Matthey (JMAT) jumped 7.2% to £27.71 despite an 11% drop in revenues which translated to a 9% fall in pre-tax profit. Buoyed by continued growth in its Environmental Technologies Division, the £5.3 billion cap which produces platinum and palladium for catalytic converters was the FTSE 100's biggest gainer on Wednesday.

European low-cost airline Easyjet (EZJ) revealed a 3.4% rise year-on-year rise in May passenger numbers, with load factors ticking up marginally from 88% to 88.1%. Yet shares in the Luton-based £4.8 billion cap fell 2.2% to £12.07.

Defence technology play Ultra Electronics (ULE) ticked up 1.8% to £17.33 after it announced the acquisition of privately owned peer Varisys in a £16 million deal.

Low & Bonar (LWB)'s pre-close trading statement showed sales within the flooring, industrial, transport and artificial grass yarns sectors were comfortably ahead of last year. But the construction materials group also revealed that first-half profits would be around £2 million lower than last year, causing the shares to slip 0.8% to 64.5p.

Newmark Security (NWT:AIM) jumped 10% to 1.65p after reporting a 'material improvement' in trading profitability and signalling the return of dividend payments.

Airline catering provider Journey (JNY:AIM) was flat at 115.5p despite winning a new contract to feed FedEx crew members on 70 flights per week out of Los Angeles.

Microcap healthcare equipment and services group Physiomics (PYC:AIM) soared 52.4% to 0.16p amid a new contract for its virtual tumour clinical and data analysis services.

Online gaming start-up Zattikka (ZATT:AIM) fell 2.7% to 36.5p as investors viewed the company's growth gameplay with scepticism. It ran-up $2.2m of losses last year on $10.2 million of revenues, with no past comparables given a spate of acquisitions in 2012. In an interview with Shares last year (here, page 40) chief executive Mark Opzoomer denied that his business was the same as Zynga's (ZNGA:NDQ), which is laying off staff by the hundred, but perhaps the market sees it differently.

Low-cost African carrier Fastjet (FJET:AIM) advanced 27.6% to 0.86p after May passenger sales in Tanzania were comfortably ahead of previous records. This relief rally followed a warning last week by Fastjet's auditor that the airline may struggle to keep trading.

Set-top box specialist Amino Technologies (AMO:AIM) added 0.75p to 83p after saying it would meet market expectations. This implies flat revenues of about £20 million, largely due to a shift away from large contracts to cash generative projects. This is leading to a margins boost that implies EBITDA (earnings before interest, tax, depreciation and amortisation) of £6.6 million, while cash in the bank stands at £18.2 million.

Supercapacitor energy storage microcap CAP-XX (CPA:AIM) unveiled new orders from several big automotive manufacturers, causing the shares to jump nearly 12% to 7.12p.

Investors were minded to take profits in Eastern European firm Frontera Resources (FRR:AIM), down 27.5% at 0.91p, despite confirming its Mtsare Khevi Field in Georgia will commence production in the next three months as planned. Year-to-date the shares are still ahead 129.3%.

Shares in oil explorer Falkland Oil & Gas (FOGL:AIM) were up 5.5% to 26.7p after it announced the completion of a 3D seismic survey on its acreage in the South Atlantic. The fully-processed results are expected in the fourth quarter of the year.

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Issue Date: 06 Jun 2013