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What: Shares of Mistras Group (NYSE:MG) were falling flat today, dropping as much as 12% after reporting a disappointing quarter.  

So what: Mistras, which provides energy infrastructure services, said revenue increased 28% in the quarter to $133.9 million, while earnings came in at $0.09 per share, down from $0.13. Sales were enough to beat estimates, but earnings were well short of the experts' view at $0.17. Much of Mistras' revenue growth also came from acquisitions, as organic sales increased 10%. CEO Sotirios Vahaviolos pointed to improvements in international sales but also said that changes in the sales mix led to lower profits. Management now expects fiscal-year revenue to come in the high end of its guidance of $525 million to $535 million, in line with analyst estimates, but it lowered its EBITDA guidance.

Now what: It's never a good sign when profits move in the wrong direction, but the top-line beat should help reassure investors. Management also expressed confidence in long-term growth prospects, and if sales increase, profits should eventually follow. I wouldn't change my investing thesis based on today's report alone.

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