Also. . .

* Los Angeles-based Northrop Grumman Corp., the No. 5 defense contractor, has received a $244-million contract from the Air Force to produce two more JSTARS ground surveillance aircraft. Northrop is getting the money to build the 12th and 13th of 14 JSTARS, or Joint Surveillance Target Attack Radar System, aircraft the Defense Department plans to buy. The aircraft would be delivered in December 2001 and May 2002, respectively. JSTARS is the Pentagon’s top aircraft for tracking ground targets. It was used during the recent conflict in Kosovo.

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* El Segundo-based Interdent Inc., a provider of dental management services, reported second-quarter net income of $2.5 million, or 11 cents per share, compared with $935,000, or 4 cents, a year ago. Revenue rose to $59.9 million from $31.5 million.

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* Keystone Automotive Industries Inc., a Pomona-based distributor of auto body parts to collision repair shops, reported a 42% jump in fiscal first-quarter net income of $5.5 million, or 33 cents per share, compared with $3.9 million, or 26 cents, a year ago. Sales rose to $101.4 million from $69.9 million last year.