Among the companies with shares expected to actively trade in Wednesday's session are Xyratex Ltd. (XRTX), Globecomm Systems Inc. (GCOM) and Steel Dynamics Inc. (STLD).

Xyratex lowered its fiscal third-quarter revenue expectations, pointing to reduced demand from large customers in its core enterprise data-storage division and deferrals in meeting acceptance testing criteria for its latest products. The storage-systems provider's shares sank 17% to $8.93 after hours.

Globecomm's fiscal fourth-quarter earnings more than tripled as infrastructure revenue at the provider of satellite-based communication services increased, though service revenue and margins weakened. Shares plummeted 21% to $10.50 after-hours as the company forecast results for the new fiscal year below analyst expectations.

Steel Dynamics expects third-quarter earnings to come in far short of Street expectations, as the steel maker sees shipments falling. Shares of the company fell 4.8% in after-hours trading to $11.69.

Facebook Inc. (FB) Chief Executive Mark Zuckerberg made his first public comments since his firm's flawed initial public offering of stock on Tuesday, and acknowledged that his diminished stock price might encourage some employees to leave. Shares were up 3.5% to $20.10 after hours.

Red Lion Hotels Corp. (RLH) has suspended its review of strategic alternatives after the midscale hotels company didn't receive any buyout or merger offers. Shares fell 6.9% to $7.20 after hours.

Santarus Inc. (SNTS) said an advanced study of an investigational antibiotic met its primary endpoint in treating travelers' diarrhea. Shares jumped 3.7% in after-hours trading to $8.09.

Teekay Offshore Partners LP (TOO) plans to offer roughly seven million of its common units, representing limited partner interests. The provider of marine transportation and other services to the offshore oil industry had about 70.6 million units outstanding as of June 30. Shares were off 4.6% to $27.43 after hours.

Vanguard Natural Resources LLC (VNR) is offering six million of its common units, representing limited-liability company interests. The oil and gas exploration company had about 51.6 million common units as of Aug. 1. Units were down 4.4% to $27.41 after hours.

 
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PepsiCo Inc. (PEP) President John Compton is leaving the global food and beverage giant to become chief executive of privately held Pilot Flying J, which operates truck stops and convenience stores.

Medical staffing company Team Health Holding Inc.'s (TMH) principal stockholder, Ensemble Health LLC, is offering eight million shares. The selling shareholder is an affiliate of the Blackstone Group L.P. (BX), which owns about 26.4 million shares--or a roughly 39% stake in the company, according to a regulatory filing. After the offering, Blackstone and its affiliates are expected to own between roughly 26% and 27% of the company shares.

Texas Instruments Inc. (TXN) narrowed its third-quarter revenue outlook around the midpoint of its guidance and lifted the lower end of its earnings outlook as an insurance payment and cost cuts masked softer demand.

Trina Solar Ltd. (TSL) unveiled plans to streamline its business, including plans to separate its photovoltaic module and systems units, as the Chinese solar-products maker looks to cut costs amid an increasingly competitive solar PV industry.

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

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