Chilean President Sebastian Pinera (second left) and other regional leaders ditched ties at a summit

The authorities in Chile are encouraging men to leave their ties at home during the coming summer months to save energy.

The country's energy minister Rodrigo Alvarez said the measure would help reduce the use of air conditioning and lead to overall energy savings.

Weather forecasters expect temperatures of over 30C (86F) this summer.

The Energy Ministry said letting the temperature of a room rise by 1-3C would reduce energy costs by around 3%.

In a statement, it said that if this was implemented in the public and private sectors during the hottest months of the year, from January to March, it could save about £6.5m ($10m).

Mr Alvarez said the idea of encouraging employees to leave their ties at home had already been put into practice successfully in Japan and Spain

Tyson Balcomb quit Facebook after a chance encounter on an elevator. He found himself standing next to a woman he had never met — yet through Facebook he knew what her older brother looked like, that she was from a tiny island off the coast of Washington and that she had recently visited the Space Needle in Seattle.

“I knew all these things about her, but I’d never even talked to her,” said Mr. Balcomb, a pre-med student in Oregon who had some real-life friends in common with the woman. “At that point I thought, maybe this is a little unhealthy.”

As Facebook prepares for a much-anticipated public offering, the company is eager to show off its momentum by building on its huge membership: more than 800 million active users around the world, Facebook says, and roughly 200 million in the United States, or two-thirds of the population.

But the company is running into a roadblock in this country. Some people, even on the younger end of the age spectrum, just refuse to participate, including people who have given it a try.

One of Facebook’s main selling points is that it builds closer ties among friends and colleagues. But some who steer clear of the site say it can have the opposite effect of making them feel more, not less, alienated.