Shares of MTC Technologies ( MTCT) were among the Nasdaq's losers Tuesday, falling 20% after the company posted second-quarter earnings that fell short of expectations and warned that third-quarter results would fall short of Wall Street forecasts.

The company, which provides system engineering, technical and management services to the federal government, earned $5.1 million, or 32 cents a share, on sales of $89.7 million. Analysts polled by Thomson First Call were expecting earnings of 34 cents a share on sales of $91.1 million. A year ago the company earned $4.2 million, or 27 cents a share, on sales of $62.7 million.

Looking ahead, MTC Technologies forecast third-quarter earnings of $5.05 million to $5.55 million, or 32 cents to 35 cents a share, on sales of $96.2 million to $101.2 million. Analysts had been expecting earnings of 41 cents a share on sales of $110.7 million. "The ongoing global war on terror and other factors are causing delays in the bidding/award process and are affecting funding availability and the availability of assets to be repaired or upgraded," the company said. Shares were trading down $7.68 to $30.05.

Pentair ( PNR) fell 9% after the company posted second-quarter earnings that matched forecasts but warned that third-quarter earnings would be well below analysts' expectations. The water-treatment products company earned $64.5 million, or 63 cents a share, on sales of $788.5 million. Analysts were expecting earnings of 63 cents a share on sales of $786.8 million. A year ago the company earned $42 million, or 42 cents a share, on sales of $530.4 million. Looking ahead, Pentair forecast third-quarter earnings of 43 cents to 47 cents a share. Analysts had been expecting earnings of 54 cents a share. Shares were trading down $4.09 to $40.39.

Shares of Rent-A-Center ( RCII) fell 6% after the rent-to-own operator posted second-quarter earnings that were a penny short of expectations and said that third-quarter earnings would be weaker than expected. The company reported pro forma earnings of $39.6 million, or 52 cents a share, on sales of $580.6 million. Analysts were expecting earnings of 53 cents a share on sales of $575.1 million. A year ago the company earned $51.2 million, or 62 cents a share, on sales of $573 million. The company said the year-over-year decline in earnings was attributed to a decrease in same-store sales and higher operating expenses.

Looking ahead, Rent-A-Center said that its business environment remains challenged. "We currently have fewer agreements on rent relative to our prior expectations due to weaker than expected demand in June and to date in the month of July," it said. The company forecast third-quarter earnings of 38 cents to 42 cents a share on sales of $572 million to $580 million. Analysts had been expecting earnings of 51 cents a share on sales of $571.7 million. Shares were trading down $1.47 to $21.86.

Timberland ( TBL) fell 10% after the company posted a second-quarter decline in earnings and said that it expects a more challenging third quarter. The shoe company reported earnings of $6.3 million, or 9 cents a share, on sales of $240.3 million. Analysts were expecting earnings of 9 cents a share on sales of $235.5 million. A year ago the company earned $7.9 million, or 11 cents a share, on sales of $230.2 million. Looking ahead, Timberland said that its third-quarter would be more challenging from a profit perspective. The company expects pressure on U.S. sales and margins, which will likely result in an overall gross margin decline of about 100 basis points, it said. Shares were trading down $3.90 to $35.86.

Shares of InFocus ( INFS) fell 17% after the company posted a second-quarter loss that was wider than expected. The company reported a loss of $19.6 million, or 49 cents a share, on sales of $135.8 million. Excluding charges, the company would have reported a loss of $16.6 million, or 42 cents a share. Analysts were expecting a smaller loss of 36 cents a share on sales of $130.5 million. A year ago the company earned $426,000, or 1 cent a share, on sales of $162.2 million. Looking ahead, InFocus said that factors that impacted its performance during the first half of 2005 are expected to continue during the third quarter and beyond. "Aggressive price competition across the industry is expected to continue putting pressure on both revenues and gross margins," the company said. Shares were trading down 77 cents to $3.79.

NYSE volume leaders included Motorola ( MOT), up 7 cents to $20.61; Texas Instruments ( TXN), up $1.65 to $32.25; Lucent Technologies ( LU), up 4 cents to $2.90; DuPont ( DD), down $3.07 to $40.97; Nokia ( NOK), up 27 cents to $15.45; Avaya ( AV), up $1.45 to $10.68; Taiwan Semiconductor ( TSM), down 33 cents to $8.68; Pfizer ( PFE), down 2 cents to $26.40; EMC ( EMC), down 30 cents to $13.95; and General Electric ( GE), up 11 cents to $34.88.

Nasdaq volume leaders included Cisco Systems ( CSCO), up 16 cents to $19.01; Intel ( INTC), up 11 cents to $26.63; Microsoft ( MSFT), down 4 cents to $25.65; Oracle ( ORCL), up 12 cents to $13.91; Tellabs ( TLAB), up 51 cents to $9.40; Netflix ( NFLX), up $2.44 to $19.40; Sirna Therapeutics ( RNAI), up $1.24 to $5.29; eBay ( EBAY), down 88 cents to $40; Sun Microsystems ( SUNW), up 2 cents to $3.87; and Sirius Satellite Radio ( SIRI), down 1 cent to $6.99.

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