The U.S. electrical grid is a complex system of power plants, transmission lines, and local distribution networks that deliver power to homes and businesses. It comprises three major grids - Eastern, Western and Texas - which are divided into hundreds of smaller sections. A summary of how power flows on the system, who oversees it and what went wrong in the August 2003 blackout:
WASHINGTON (AP) - Scientists who sparked an outcry by creating easier-to-spread versions of the bird flu for research purposes want to try such experiments again using a worrisome new strain. This time around, the U.S. government is promising extra scrutiny of such high-stakes research up front.
NEW YORK (AP) - The U.S. electrical grid is better managed and more flexible a decade after its largest blackout but remains vulnerable to increasingly extreme weather, cybersecurity threats, and stress caused by shifts in where and how power is produced.
DETROIT (AP) - Nearly 51 hours after jumping into a lake near the Michigan-Canada border, a long-distance swimmer who calls himself "The Shark" finished his 22-mile journey to Detroit while hauling hundreds of pounds of bricks.
LOS ANGELES (AP) - In a rare diplomatic rebuke, President Barack Obama called off an upcoming Moscow summit with Russian President Vladimir Putin on Wednesday, sending a stern message of disapproval over Russia's harboring of National Security Agency leaker Edward Snowden.
INDIANA COMMUNITY HANDS OUT DRUG TESTING KITS: LAWRENCEBURG, Ind. (AP) - A southeastern Indiana school is distributing kits so parents can test their children for drug use.
RENO, Nev. (AP) - A biker gang leader was convicted of murder Wednesday in the 2011 killing of a Hells Angels member at a Nevada casino that authorities said was part of an orchestrated assassination plot to take out a high-ranking official of the rival group.
WASHINGTON (AP) - Smartphones don't make smart babies, an advocacy group declared Wednesday in a complaint to the government about mobile apps that claim to help babies learn.
ATLANTA (AP) - Higher blood-sugar levels, even those well short of diabetes, seem to raise the risk of developing dementia, a major new study finds. Researchers say it suggests a novel way to try to prevent Alzheimer's disease - by keeping glucose at a healthy level.
DES MOINES, Iowa (AP) - The allure of capturing the estimated $425 million Powerball jackpot had players in a buying frenzy Wednesday, further confirming a trend that lottery officials say has become the big ticket norm: Fatigued Powerball players, increasingly blase about smaller payouts, often don't get into the game until the jackpot offers big bucks.
FORT HOOD, Texas (AP) - On the first day Maj. Nidal Hasan went on trial in a fight for his life, he claimed responsibility for the 2009 shooting rampage at Fort Hood. He posed no questions to most witnesses and rarely spoke. On one of the few times he did talk, it was to get on the record that the alleged murder weapon was his, even though no one had asked.
LOS ANGELES (AP) - Coastal waters off California are getting more acidic. Fall-run chinook salmon populations to the Sacramento River are on the decline. Conifer forests on the lower slopes of the Sierra Nevada have moved to higher elevations over the past half century.
NEW YORK (AP) - Publishers who have settled an electronic book pricing dispute with the federal government objected Wednesday to penalties the government wants to impose on Apple Inc., saying it will hurt publishers rather than the personal electronics giant.
North Bend, Ore. (AP) - David Wonnacott qualified for a tattoo license on July 5 and wasted little time establishing a business in a small, coastal Oregon community. Problem is, police said, he did it with a gun.
SECAUCUS, N.J. (AP) - The Children's Place has stopped selling a T-shirt that sparked complaints of sexism.
WITNESSES: SKYDIVERS WHO DIED DESCENDED TOO FAST: BARNSTABLE, Mass. (AP) - The two skydivers killed after they crashed into a building during a tandem jump on Cape Cod appeared to be having problems as they descended, police said.
NEW YORK (AP) - When the economy tanks, women have fewer babies. But what happens in the following years, when conditions improve?
NEW YORK (AP) - Macy's plans to hire about 86,000 seasonal holiday workers nationwide to bolster its stores, call centers and distribution hubs, a 3.6 percent increase from last year.
FERGUSON, Missouri (AP) - Authorities searched Sunday for a suspect in the shooting of a police officer in Ferguson, the St. Louis suburb where there have been angry protests since a white officer fatally shot an unarmed 18-year-old black man last month.
TOKYO (AP) - Finally reaching the ash-covered summit of a still-erupting volcano in central Japan, rescue workers made a grim discovery Sunday: 31 apparently dead people, some reportedly buried in knee-deep ash.
MIAMI (AP) - A shooting sent terrified patrons scrambling from a Miami nightclub early Sunday and left 15 people wounded, including an 11-year-old child, authorities said.
CHICAGO (AP) - Teen girls who have sex should use IUDs or hormonal implants - long-acting birth control methods that are effective, safe and easy to use, the nation's most influential pediatricians' group recommends.
COLORADO SPRINGS, Colo. (AP) - A marijuana giveaway for veterans attracted about 1,000 people to a Colorado hotel.
ALBUQUERQUE, N.M. (AP) - A northern New Mexico sheriff who has fought off accusations of misconduct throughout his career was convicted Friday of abusing a driver during a bizarre traffic stop that prosecutors called a fit of road rage.
LAS VEGAS (AP) - The arrests of several protesters for writing anti-police messages with chalk on a sidewalk last year have spawned a federal civil rights lawsuit against Las Vegas police.
OKLAHOMA CITY (AP) - A man fired from an Oklahoma food processing plant beheaded a woman with a knife and was attacking another worker when he was shot and wounded by a company official, police said Friday.
ALEXANDRIA, La. (AP) - A Mississippi man who was once declared dead, only to resurface as a suspect in a kidnapping and killing, was sentenced to death Friday after a jury earlier convicted him of murder.
SPRINGFIELD, Mass. (AP) - A man who has bumps resembling horns implanted in his forehead was found guilty of murder and other charges Friday for his role in the kidnapping and slaying of three Massachusetts men in 2011.
RALEIGH, N.C. (AP) - A North Carolina inmate with mental illness who died of thirst was held in solitary confinement for 35 days and cited twice for flooding his cell, according to prison records.
COLUMBIA, S.C. (AP) - A South Carolina state trooper's dashboard video shows an unarmed driver being shot just seconds after he was stopped for a seatbelt offense - and the trooper, who was fired last week, has now been charged with assault.