Also

Nortel Networks Corp. of Canada, North America’s No. 2 phone equipment maker, agreed to buy Periphonics Corp. of New York for $436 million in stock to gain equipment that links voice, data and Internet services.

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* Seagate Technology Inc., the world’s largest independent maker of disk drives, said it will cut 1,600 jobs in Singapore as the Scotts Valley, Calif.-based company trims costs to become more competitive.

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* Getty Images Inc. of Seattle, the only publicly traded image archive, has acquired Internet-based photography provider Online USA Inc. for about $2 million in stock to bolster its coverage of celebrities and events.

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* Software maker QAD Inc. of Carpinteria, Calif., reported a second-quarter net loss, excluding charges, of $2.8 million, or 9 cents per share, compared with a loss of $4.4 million, or 15 cents, a year ago. Revenue rose to $58.3 million from $47.3 million.