A section of the brain involved in memory grew in size in older people who regularly took brisk walks for a year, researchers reported Monday.

The new study reinforces previous findings that aerobic exercise seems to reduce brain atrophy in early-stage Alzheimer's patients, and that walking leads to slight improvement on mental tests among older people with memory problems.

The last of Egypt's main Internet service providers, the Noor Group, has gone dark.

The Noor Group had remained online even after Egypt's four main Internet providers — Link Egypt, Vodafone/Raya, Telecom Egypt, Etisalat Misr — abruptly stopped shuttling Internet traffic into and out of the country Friday morning.

Omar Sharif, Egypt's most famous actor, says he's concerned for the future of his country.

Cairo's Tahrir Square, where protests have been centered, is visible from his high-rise apartment and helicopters buzz overhead.

Lebanon's recent political turmoil is likely to scare off Western travelers although Beirut has repeatedly proven its resilience, emerging from civil war and conflict with Israel to rebuild and live up to its image as the "Switzerland of the Middle East," the Associated Press reported.

"People's memories are surprisingly short," says Janet Moore, owner of Distant Horizons, a Long Beach, California, travel agency specializing in the Middle East.

South Korea's president pressed North Korea on Tuesday to change its pattern of provocations and take responsibility for two deadly attacks last year, saying that could lead to a summit with North Korean leader Kim Jong Il.

President Lee Myung-bak's appeal came as the rival Koreas are to hold a preliminary meeting next week to lay the groundwork for high-level defense talks — the first in more than three years — to ease months of hostility on the Korean peninsula that have raised fears of war.

Novak Djokovic's commanding Australian Open win over Andy Murray broke the Federer-Nadal Grand Slam monopoly and heralds a new era for men's tennis, Australian media said Monday.

The Serbian world number three dominated Sunday's three-set clash with a display described as "crushing" by the local press.

Paul Pierce says the Boston Celtics had no reason to discuss their heartbreaking loss in Game 7 of the NBA finals last summer before they returned to Staples Center on Sunday.

With a spectacularly fluid performance on offense against the outclassed Lakers, Pierce and the Celtics showed some things just don't need to be said out loud.

World stock markets sank Monday as investors sought less risky investments amid anti-government riots in Egypt that are damaging the economy of the Arab world's most populous country and threaten to spread instability elsewhere in region.

Oil prices rose to near $90 a barrel as fears escalated that protests in the city of Suez at the mouth of the strategic waterway — a key route for oil tankers and cargo ships — could interrupt the flow of oil. In currencies, the dollar was higher against the yen but lower against the euro.

The United States started organizing Sunday the evacuation of its nationals from Egypt as an angry anti-government revolt raged into a sixth day amid increasing lawlessness and mass jail breaks.

"The U.S. embassy in Cairo informs U.S. citizens in Egypt who wish to depart that the department of state is making arrangements to provide transportation to safehaven locations in Europe," an embassy statement said, as other countries issued travel warnings and tourists scrambled for flights out.

Saudi King Abdullah has told U.S. President Barack Obama that there should be no bargaining on Egypt's stability and the security of its people, the Saudi press agency said Sunday.

SPA said that Obama phoned the king in Morocco, where he is recuperating from surgery, and that both leaders were not happy with the chaotic situation and looting.