The Nasdaq rose Tuesday as Apple Computer Inc. (AAPL) unveiled a hotly anticipated mobile phone and boosted optimism about the tech sector, while blue-chip stocks slipped as energy shares fell on lower oil prices.

The Dow Jones industrial average fell 6.89 points, or 0.06 percent, to end at 12,416.60. The Standard & Poor's 500 Index was down 0.72 points, or 0.05 percent, at 1,412.12. The Nasdaq Composite Index was up 5.63 points, or 0.23 percent, at 2,443.83

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A profit warning by Sprint Nextel Corp. (S), which sparked concern about the outlook for earnings gains just as the quarterly reporting season gets under way, also kept a lid on the broader market.

Investors were keenly awaiting results after the bell from Alcoa Inc. (AA), the first Dow component to report results. The world's largest aluminum producer posted a rise in fourth-quarter profit that surpassed most analysts' expectations.

Shares of Alcoa jumped 6.1 percent to $30.25 in after-hours trade, after closing at $28.52 in regular New York Stock Exchange trade.

Oil prices dropped to their lowest in 18 months, but ended off their worst levels of the day, causing a fall in major energy companies including ConocoPhillips (COP) and Exxon (XOM) Mobil Corp.

Apple unveiled a mobile phone with a touch-screen that combines features from its iPod music player, sending its shares higher and lending support to the market. .

"There is a lot of enthusiasm over Apple," said Tim Woolston, portfolio manager at Boston Advisors Inc. in Boston. Also, "you've got a lot of folks suggesting that '07 will be a good year for tech earnings because of capital expenditure budgets."

Apple's stock, which rose 8.3 percent, or $7.10, to $92.57, was the biggest positive influence on the Nasdaq and the S&P 500 index. Shares of AT&T (T), whose Cingular Wireless unit is Apple's U.S. cellular partner, also rose, gaining 0.4 percent, or 13 cents, to $33.94.

Shares of U.S. power company AES Corp. dropped 4.1 percent, or 86 cents, to $20.16 after Venezuelan President Hugo Chavez said he would seek to nationalize utilities and telecommunication companies. The announcement also created a sell-off in Latin American shares.

Although Chavez did not specify which electricity companies would be nationalized, AES's Electricidad de Caracas, or EDC, is the largest privately owned utility in Venezuela.

Sprint was the top drag on the S&P 500 index. Sprint shares tumbled 11.2 percent, or $2.19, to $17.45 after the No. 3 U.S. mobile service provider said late on Monday that profit in 2007 will remain under pressure due to lower margins and revenue will be flat or slightly higher.

On the New York Mercantile Exchange, February crude fell 45 cents, or 0.8 percent, to settle at $55.64 a barrel, after trading as low as $53.88 earlier.

A warm winter in the U.S. Northeast, the key heating oil market, has combined with ample crude and fuel supplies to spur long liquidations, analysts said. The day's low was the weakest front-month crude price since $53.05 was hit on June 13, 2005.

Shares of Exxon Mobil fell 0.8 percent, or 56 cents, to $72.09, while shares of ConocoPhillips declined 2.6 percent, or $1.79, to $66.51.

Trading was active on the NYSE, with about 1.71 billion shares changing hands, below last year's estimated daily average of 1.84 billion, while on Nasdaq, about 2.19 billion shares traded, above last year's daily average of 2.02 billion.

Advancing stocks outnumbered declining ones by a ratio of about 9 to 7 on the NYSE, while decliners outnumbers advancers by 15 to 14 on Nasdaq.

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