NEW YORK (Reuters) - Stocks closed mostly flat on Tuesday after volatility late in the session, with weakness in materials and energy shares offsetting strength in financials. Shares traded higher for much of the session on the back of an unexpectedly strong read on existing home sales, which lifted banks. But those gains dissipated in the last half hour of trading, with Wall Street briefly turning solidly negative before staging a rebound. ...

NEW YORK (Reuters) - Former Goldman Sachs director Rajat Gupta was once on hedge fund billionaire Raj Rajaratnam's "important people" list but excluded from a fantasy football celebration helicopter trip to Atlantic City with other corporate high-flyers. On the second day of Gupta's insider-trading trial in Manhattan federal court on Tuesday, prosecutors tried to establish for the jury his ties to now-imprisoned Rajaratnam, while defense lawyers sought to describe some distance between the men. Gupta, 63, is the most prominent corporate figure indicted in a broad U.S. ...

(Reuters) - Two top U.S. financial regulators said the issues around the initial public offering of Facebook should be reviewed, putting fresh pressure on the company, its embattled lead underwriter and the Nasdaq. After Friday's nearly flat close and Monday's 11 percent plunge, Facebook shares closed 8.9 percent lower at $31 on volume of 101 million shares. At that price the company has shed more than $19 billion in market capitalization from its $38-per-share offering price last week. ...

CHICAGO (Reuters) - From a chilly perch in Burnsville, Minnesota, Tim Zemanovic has an usual perspective on the global aircraft market, which is booming - some say overheating - as the world's largest plane-makers pump out jets as fast they can. Zemanovic, the head of Aircraft Demolition, a company that tears down and recycles unwanted airplanes, says his five-year-old business has never been stronger as airlines expand and replenish their fleets with fuel-efficient planes. "This year, I expect to do double the work we did last year," he said. ...

BEIJING (Reuters) - The World Bank cut its economic growth forecast for China this year to 8.2 percent on Wednesday and urged the country to rely on easier fiscal policy that boosts consumption rather than state investment to lift activity. In a biannual East Asia and Pacific economic update, the World Bank said a slowing China will drag growth in emerging East Asia to two-year lows this year, but warned Europe's seething debt crisis could inflict even bigger damage if it worsens. Sluggish U.S. ...