The United States will propose an emissions reduction target at a U.N. climate change summit in Copenhagen, a senior administration official said.

Many sewer systems are overwhelmed, spilling excrement, medical waste and chemicals into waterways.

President Luiz Inácio Lula da Silva is drawing criticism for receiving Iran’s president, Mahmoud Ahmadinejad, in his first state visit to Brazil.

As an ethics investigation continues, Representative Charles B. Rangel’s once-considerable clout has diminished, and signs of stress are starting to show.

Representative Patrick J. Kennedy said he was instructed to refrain from communion because of his stance on abortion.

The effects of a decision on executing mentally retarded inmates could offer a lesson on punishment for juveniles.

The ultralow interest rates the U.S. has been paying on its colossal debt may not last much longer, and the White House estimates that the tab will exceed $700 billion a year in 2019.

The plan will enlist companies and nonprofits, including “Sesame Street,” to spend money and time to encourage students to pursue science, technology, engineering and math.

Anxious about how little maneuvering room the weekend victory on health care provided, Democrats are stepping up overtures to two moderate Republican senators from Maine.

A primer on the military utility of some of the force options before President Obama to bolster the 68,000 American troops already in Afghanistan.

Ahmed Khalfan Ghailani’s case in Manhattan could be important in a future trial of Khalid Shaikh Mohammed, accused of planning 9/11.

Whether benefits from the president’s policies will be realized in time for the elections in 11 months is a big question.

The U.S. Preventive Services Task Force thought its review of breast cancer recommendations would be a straightforward job, but the response to its guidelines was swift and angry.

The Nuclear Regulatory Commission says the small amount of radiation detected at the Three Mile Island nuclear power plant is not significant.

The Martin Luther King Jr. hospital is entering a public-private partnership for more cost-effective operations.

The Department of Homeland Security has had to stop deploying new detectors because the U.S. has run out of a crucial raw material, experts say.

In August, Southern farmers thought they had a bumper crop — the best in years. Then heavy rains in September and October spoiled the harvest.

Professor Hymes was a prominent anthropologist, linguist and folklorist whose work mined the rich, often overlooked territory where language and culture intersect.

Officials at the University of California, Santa Cruz say dozens of protesters who were occupying the university’s main administrative building have ended their protest.

Two centrist senators, Ben Nelson and Joseph I. Lieberman, said that they were opposed to the bill as it is currently written.