Twitter’s shares of stock went public for the first time Thursday and exceeded expectations, jumping more than 70 percent above the offering price. The social network was valued at $31 billion by the closing bell, and shares were selling for as much as $50.09 at one point in the day. By all accounts, Twitter’s initial public offering went smoother than Facebook’s IPO 18 months ago, which suffered glitches and fell below expectations. read full story

The Philippines were hit Thursday with a huge cyclone, which weather experts said could be the strongest ever recorded at landfall. Shortly before landfall, multiple weather readings measured sustained winds of at least 145 mph and gusts of 170 mph for Typhoon Haiyan. A weather expert said the bright side is that the storm is fast-moving, which might cause less flooding and fewer deaths, but the storm is expected to later hit Laos and Vietnam.

The Food and Drug Administration announced Thursday it would ban trans fats in the food industry. The FDA condemned the fats as a threat to public health and said getting rid of them could prevent 20,000 heart attacks and 7,000 deaths each year. The agency said it would collect comments for two months before determining the fats’ phase-out schedule so that they can find substitutes that will work in different kinds of food. read full story

Former Palestinian leader Yasser Arafat’s 2004 death came under investigation Thursday as Swiss scientists announced they had examined his remains and concluded he was probably poisoned with radioactive polonium. Hard proof remains elusive, but the scientists found traces of polonium and lead that they said could not have occurred naturally or been an accidental poisoning. Palestinian and Israeli officials have denied involvement with his death; before his death, Arafat, his advisers and bodyguards were holed up in an Israeli-besieged West Bank compound for months.