CHICAGO — Fast food workers say they're prepared to escalate their campaign for higher wages and union representation, starting with a national convention in suburban Chicago where more than 1,000 workers are expected to discuss the future of the effort that has spread to dozens of cities in less than two years.

About 1,300 workers will attend sessions today and Saturday at an expo center in Villa Park, Illinois, where they'll be asked to do “whatever it takes” to win $15-an-hour wages and a union, said Kendall Fells, organizing director of the national effort and a representative of the Service Employees International Union.

The union has been providing financial and organizational support to the fast-food protests that began in late 2012 in New York City and have included daylong strikes and a protest outside this year's McDonald's Corp. shareholder meeting that resulted in more than 130 arrests.

FOSTER CITY, Calif. — Visa Inc. said Thursday that its profit climbed 11 percent in its fiscal third quarter versus a year earlier, aided by solid growth in payments volume, service revenue and transactions.The payments processor’s latest financial results beat or matched Wall Street expectations. But its stock slid 3 percent in extended trading after the company tempered its earnings outlook for the year, citing issues including a stronger U.S. dollar and slow growth in cross-border transactions, or when someone uses a Visa card outside the country where it was issued.In a conference call with Wall Street analysts, Visa’s Chief Financial Officer Byron Pollitt noted that the company is guardedly optimistic that the slowing of cross-border volume growth has bottomed.“In short, we are approaching 2015 bullish on the long term but cautious in the short-term,” Pollitt said.