Among the companies with shares expected to actively trade in Thursday's session are Guess Inc. (GES), Hewlett-Packard Co. (HPQ) and Hain Group Inc. (HAIN).

Guess's fiscal second-quarter income fell 29% as the apparel maker saw continued weakness in Europe and lower sales in North America overshadow significant growth in its Asian operations. Shares plummeted 16% after hours to $28.09 after the company predicted weak third-quarter results and again lowered its full-year guidance.

Hewlett-Packard reported the worst-ever loss in its 73-year history as the technology giant's ongoing struggles were compounded by a big writedown. The world's largest PC maker by volume also reported a decline in revenue and now sees full-year adjusted earnings at the low end of its prior guidance. Shares fell 4.8% to $18.28 after hours.

Hain Celestial has agreed to acquire Premier Foods PLC's (PFD) portfolio of packaged grocery brands for 200 million pounds sterling ($317.6 million) in cash and stock as the natural- and organic-products company looks to expand in the U.K. and also reported its fiscal fourth-quarter profit rose 82%. Shares jumped 11% to $62.94 after hours as the company also offered upbeat earnings guidance for the new fiscal year.

International Rectifier Corp. (IRF) swung to a fiscal fourth-quarter loss as demand continues to erode, and the chip maker unveiled a restructuring plan, which will include closing a plant in California. Shares fell 8% after hours to $17.

Semtech Corp.'s (SMTC) fiscal second-quarter earnings fell 63% on acquisition-related inventory adjustments and other items as the chipmaker's revenue strengthened with an added boost from a recent acquisition. Shares fell 3.3% to $23.95 in after-hours trading as the company gave a fiscal third-quarter outlook that missed analysts' expectations.

DFC Global Corp. (DLLR) swung to a fiscal fourth-quarter loss as an impairment charge weighed on the payday lender and pawnbroker's bottom-line results, while revenue grew less than expected. Shares fell 9.6% to $18after hours as the company issued guidance for the new year mostly below analyst expectations.

Swedish telecommunications gear vendor Ericsson (ERIC) has agreed to sell its fiber-access assets to U.S. broadband-equipment supplier Calix Inc. (CALX). Terms of the deal, which is expected to close in the fourth quarter, weren't disclosed. Calix shares jumped 8.7% to $5.75 after hours.

Kayak Software Corp.'s (KYAK) second-quarter profit nearly doubled as the travel website reported that revenue and total queries jumped, particularly in its mobile applications. But shares fell 4.1% after hours to $29.55 as earnings missed Street expectations.

Pacific Sunwear of California Inc.'s (PSUN) fiscal second-quarter loss narrowed as the teen-focused retailer reported stronger sales, led by its men's segment, as well as improved margins. Shares rose 9.2% to $2.37 after hours as revenue topped expectations.

Whitestone REIT (WSR) said it plans to sell 4 million shares to raise fudns for general purposes. Shares slid 3.7% to $12.85 after hours.

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Aeropostale Inc. (ARO) appointed former bebe Stores Inc. (BEBE) president Emilia Fabricant to take charge of design, merchandising and production for its Aeropostale brand.

Focus Media Holding Ltd.'s (FMCN) second-quarter earnings rose 38% as the Chinese digital-advertising company recorded strong revenue gains in its LCD display and poster frame segments.

Heico Corp.'s (HEI) fiscal third-quarter profit rose 13% as the aircraft parts and repair company recorded stronger sales from its electronic-technologies business.

Krispy Kreme Doughnuts Inc.'s (KKD) fiscal second-quarter earnings fell 44% as its year-ago period was boosted by an equity sale, though the doughnut chain's core earnings and domestic same-store sales improved.

Quality Systems Inc. (QSII) has elected two directors nominated by dissident board member Ahmed Hussein, and seven of the eight nominees named by the company, amid a long-running proxy battle.

Technology licensing firm Rambus Inc. (RMBS) said it plans to cut about 15% of its work force amid a restructuring effort expected to save the company about $30 million to $35 million annually.

Raymond James Financial Inc.'s (RJF) client assets under administration rose to a record $379 billion last month, but the company noted trading volumes in both the equity and fixed income markets were weak last month.

Synopsys Inc.'s (SNPS) fiscal third-quarter profit rose 45% as the provider of chip-design software continued to benefit from competition among chip makers, and also recorded a tax gain.

Ulta Salon Cosmetics & Fragrance Inc. (ULTA) named former Yankee Candle Co. (YCC) executive and retail veteran Bruce L. Hartman as its new chief financial officer, starting Sept. 7.

Hedge-fund manager Clinton Group Inc. said it will solicit approval from fellow Wet Seal Inc. (WTSLA) shareholders to try replacing four company board members and filling one board vacancy, saying the new team would help improve merchandising and operations and pursue a strategic transaction for the business.

-Write to Nathalie Tadena at nathalie.tadena@dowjones.com

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