LONDON -- With markets being so volatile these days, we could be forgiven for expecting the FTSE 100 (INDEX: ^FTSE) to slump again today. But with optimism from the G20 summit and expectations that the eurozone is closer to a deal to lower borrowing costs across the continent, the U.K.'s index of top shares retained the ground it has gained. It reached 5,597 in early trading for a small 0.1% rise.

News of falling bond yields -- Spain's are back just below 7% -- lent support to other indexes as well. The German DAX edged up 0.2% to 6,376, but France's CAC 40 lost a few points to fall to 3,108.

Top risers
Healthcare Locums put on a nice 20% rise this morning, after legal action against the company in the U.S. -- brought by a number of investment managers -- was dropped. Up 0.7 pence, the shares reached 4 pence in early trading.

Irish flag-carrier Aer Lingus was a big early riser today on the announcement of a new offer from Ryanair Holdings (LSE: RYA.L) for 100% of its share capital. The share price rose 18% to 1.09 euros, while Ryanair's price blipped up a fraction to 4.01 euros.

Blinkx, the maker of smart video search software, enjoyed some respite today with the announcement of a new partnership with news network Newsy. The hard-pressed shares regained 2.8 pence, or 7.5%, to 40.3 pence.

Accounting software expert Sage Group (LSE: SGE.L) perked up on the acquisition of a Brazilian software company, gaining 3% to reach 261 pence.

Fallers
Kesa Electricals (LSE: KESA.L), the European chain and former owner of the U.K.'s Comet, released full-year results today, telling us that "markets throughout Europe have been exceptionally difficult." Adjusted pre-tax profit fell by nearly a half, prompting the shares to lose 9% to 50 pence; they're now down 60% on the year. The firm will also change its name to Darty, after its flagship European outlet.

Braemar Shipping (LSE: BMS.L), which has had a rocky ride this year, saw its shares slump by 30 pence for an 8% fall to 326 pence after an interim management statement told of weakness in some sectors of its business.

Minerals and oil
Gold, minerals, and oil explorers figured in early news, too, with Cluff Gold gaining a shiny 5% to 71 pence following a new gold discovery in Cote d'Ivoire. But antimony miner Tri-Star Resources fell 10% to 0.7 pence after the release of its latest operational update.

The news wasn't good for Gold Oil, which has seen its share price boom and bust in recent months. Today's bad news took the form of a disappointing trading update, and the shares dropped 6% to 4.2 pence.

But Sirius Minerals saw a small 4.5% rise to 16.5p after the appointment of Alan Watling as new managing director of one of its projects.

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