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A roundup of the latest high-tech news “Hot Off the Wire” from The Associated Press and Local Tech Wire:

• Arcade Fire, John Legend to stream concerts live

NEW YORK — American Express is launching a new online concert series dubbed "Unstaged," with shows to be streamed live on YouTube and Vevo.

Arcade Fire will kick off the series by live streaming the second of their much-anticipated Aug. 4 and 5 concerts at Madison Square Garden, which follow the release of the band’s third album, "The Suburbs."

The concert will stream live at 10 p.m. Aug. 5 on the Google Inc.-owned YouTube and Vevo, the music video site owned by Universal Music Group, Sony Music Entertainment and Abu Dhabi Media Co.

It’s the first in a planned series of five live concerts, with John Legend and the Roots to follow, and others later.

• Xerox earns soar following ACS buyout

SAN FRANCISCO — Xerox Corp.’s (NYSE: XRX) net income jumped 62 percent in the second quarter as the company reaped the benefits of its $6 billion acquisition of outsourcer Affiliated Computer Services and notched strong printer sales.

Shares leapt 6 percent after the company raised its 2010 guidance.

The numbers, reported Thursday, show the effects of Xerox’s transformation with the ACS acquisition and underline the fact that companies are spending more on technology as their budgets mend. That trend has been illuminated in the past couple of weeks by other heavyweights such as Intel Corp., IBM Corp. and EMC Corp.

Yet the quarterly reports have largely been overshadowed by worries over the health of world markets and the possibility orders could evaporate as the year rolls on.

Xerox’s CEO, Ursula Burns pointed to "some signs of life" in spending by large corporations. She said business in Europe is "pretty strong" despite the debt crisis and worries the governments of Greece, Portugal and Spain could default on loans.

The company’s clients are still smarting from the nasty economic downturn, yet there are signs that the recovery has gained momentum in the right direction.

"Clearly, there’s caution. Clearly, there are questions," she said on a conference call with analysts. "But what we see is continued investment in color, continued investment in the new technologies we’re putting out and definitely continued investment in services."

• Amazon profits soar but don’t meet expectations

SAN FRANCISCO — Inc. (Nasdaq: AMZN) said Thursday that its second-quarter net income jumped, bolstered by shoppers who spent more with the online retailer even as consumer confidence fell overall.

But the Seattle-based company’s earnings fell below analyst expectations, and its stock dove in after-hours trading.

For the April-June quarter, earned $207 million, or 45 cents per share. That’s a 45 percent increase from $142 million, or 32 cents per share, in the same quarter last year.

Analysts polled by Thomson Reuters were looking for 54 cents per share, but rising operating expenses cut into Amazon’s profit growth.

Overall, operating expenses grew 40 percent to $6.3 billion. Part of that resulted from rising fulfillment costs — $582 million, compared with $409 million last year. The company’s cost of sales, which naturally rises along with revenue, grew, too.

In a conference call with journalists to discuss the company’s results, Chief Financial Officer Tom Szkutak attributed much of the expense growth to Amazon’s efforts at increasing its ability to fill orders. The company is adding 13 fulfillment centers this year, he said, and hired 2,200 people during the quarter.

Revenue grew 41 percent to $6.6 billion, slightly beating analyst predictions for $6.5 billion in revenue.

The growth came mainly from sales of electronics and other general merchandise, which increased 69 percent from last year to $3.5 billion. Revenue from books, CDs, DVDs and other media rose 18 percent to $2.9 billion.