The Dow Jones Industrial Average (^DJI 0.56%) has gained 86 points in pre-market trading, suggesting a positive start to the stock market today. World markets didn't move much overnight: Europe's STOXX index fell only slightly after inflation data for the eurozone registered at a five-year low.

Federal Reserve Chairwoman Janet Yellen is scheduled to give a speech on the economy this morning in Chicago. The Fed surprised Wall Street recently by suggesting that long-term interest rates could start rising sooner than expected, and Yellen may discuss more details about that timetable in her talk today, which is scheduled to begin at 9:55 a.m. EDT. 

Meanwhile, news is breaking this morning on several stocks that could see heavy trading in today's session, including Disney (DIS 0.16%), Cal-Maine Foods (CALM 1.47%), and UTi Worldwide (NASDAQ: UTIW)

Disney stock was up 1.2% in pre-market trading after its Captain America: The Winter Soldier got off to a strong start at the international box office. The Marvel film raked in $75 million in its opening weekend while playing in just a few foreign markets.

Sure, that's below the $185 million that The Avengers earned in a similar release window two years ago, but it still points to a very solid run ahead for the movie once it launches this weekend in major markets including the United States and China.

Cal-Maine Foods this morning posted a 10% quarterly sales boost to $395 million. Profit also jumped to $1.78 a share, well ahead of the $1.27 the company booked a year ago. The egg producer saw higher demand for all of its products over the holiday months, in part thanks to the unusually cold temperatures around the country. Cal-Maine's future looks bright even as the weather gets back to normal, particularly given that national restaurant chains such as Yum! Brands' Taco Bell are diving into the breakfast market. Cal-Maine's stock was unchanged in pre-market trading.

Finally, UTi Worldwide today booked weaker than expected earnings results for its fiscal fourth quarter. Sales came in at $1.1 billion, a 2% decrease from the prior-year period. The shipping and logistics company also saw its quarterly loss widen to $0.15 a share from the $0.13 it booked a year ago. CEO Eric Kircher said in a press release that those weak results reflected a "lackluster global economy and difficult operating conditions." The stock was down 0.9% in pre-market trading.