LONDON -- The FTSE 100 (UKX) is continuing to travel sideways, and at 5,633 points is just a few points ahead of yesterday's close, despite early signs that the U.K.'s index of top shares might be poised to recover some of yesterday's fall.

But daily movements in the index don't really matter. What counts is the performances of the individual companies that make up the FTSE indexes, and today we look at three that have fallen...

AEA
AEA Technology shares plunged 77% today, falling to just 0.05 pence, after the latest news of its long-standing debt problems effectively rendered the shares worthless. The firm has been in negotiations with its banks for some time to try to address its net debt and its pensions liabilities, which stood at 34.3 million pounds and 165.5 million pounds, respectively, in September last year.

But since a further profit warning in January this year, no long-term solution to the problem has been forthcoming. The board will now consider all options to find a way out, saying that "such options will result in little or no value for shareholders."

Synairgen
Alternative Investment Market-based pharmaceuticals researcher Synairgen saw its shares fall 6.5 pence (13%) to 44 pence today, but it should be good news overall as it came as a result of a new share placing.

The raising of 2.5 million pounds at 45 pence per share will enable the company to progress its asthma and COPD inhaled interferon beta program, and to work toward U.S. approval, and will provide some working capital.

The successful placing looks like providing a good confidence boost, too -- despite today's fall, the shares are still up more than 60% on the year.

LSE
The London Stock Exchange (LSE: LSE.L) lost ground this morning, falling 30 pence (3%) in early trading to 983 pence, on the day it released its first-quarter results.

The operator of one of the world's major stock markets hit its quarterly targets, with revenues rising by 10% to 209.5 million pounds. But that was largely due to its expansion into information services and boosted by acquisitions. Trading in its core capital markets appears to have been weak amid difficult conditions, and uncertainty in that business is almost certainly what gave the market the jitters.

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