World Briefs

Already threatened by a thaw of ice around the North Pole, the polar bear's title as the top Arctic predator may be under challenge from a shark.

Scientists researching how far sharks hunt seals in the Arctic were stunned in June to find part of the jaw of a young polar bear in the stomach of a Greenland shark, a species that favours polar waters.

"We've never heard of this before. We don't know how it got there," Kit Kovacs, of the Norwegian Polar Institute, told Reuters of the 10 cm bone found in a shark off the Norwegian Arctic archipelago of Svalbard.

"We can't say whether or not the shark took a swimming young bear" or ate a carcass, she said. "We don't know how active these sharks are as predators."

Most shark experts contacted said it was likely the bear was dead before the shark found it. Even a young, two- or three-year-old bear would be a ferocious opponent for a Greenland shark, which can grow to up to seven metres and weigh more than a tonne.

Finnish sauna championships

One hundred-sixty men and women from 23 countries participated in the 10th annual sauna championships in Finland, with the Finns dominating due to what Women's title winner Leila Kulin described as "sisu" - usually translated as perseverance.

Bjarne Hermansson of Finland outlasted the competition and endured the heat for 18.15 minutes.

"I have been training a lot with my brother to achieve this win," Mr Hermansson told Reuters after he was crowned the 2008 Sauna Champion late on Saturday.

Ms Kulin sweated her way to the Women's title with a time of 5.22 minutes in the sauna.

Usually people stay in a sauna for about five minutes at a time, without the extreme humidity of the contest saunas.

Invisibility cloak one step closer

Scientists have created two new types of materials that can bend light the wrong way, creating the first step towards an invisibility cloaking device.

One approach uses a type of fishnet of metal layers to reverse the direction of light, while another uses tiny silver wires, both at the nanoscale level.

Both are so-called metamaterials - artificially engineered structures that have properties not seen in nature, such as negative refractive index.

The two teams were working separately under the direction of Xiang Zhang of the Nanoscale Science and Engineering Centre at the University of California, Berkeley with US government funding. One team reported its findings in the journal Science and the other in the journal Nature.

Each new material works to reverse light in limited wavelengths, so no one will be using them to hide buildings from satellites, said Jason Valentine, who worked on one of the projects.

Ghost of Dickens haunts Edinburgh

The ghost of Charles Dickens is walking the Music Hall stage at Edinburgh's Assembly Rooms, 150 years after the great Victorian novelist appeared in person at the same location to read his works.

Veteran actor Simon Callow, who has toured the world with his acclaimed one-man show The Mystery of Charles Dickens, is appearing at the Edinburgh Fringe Festival to sell-out houses with enactments of two of the novelist's lesser known stories.

Dickens himself appeared on the Music Hall stage in March 1858 to read A Christmas Carol to a packed audience of the Philosophical Institute shortly after he had begun reading his works professionally for profit. The demand in Edinburgh was so great that extra seats had to be rushed to the hall. His readings were hugely popular through Britain and abroad, particularly in the US.

Mr Callow, in period costume, is performing Dr Marigold, which was first published in 1865 in Dickens's periodical All The Year Round, and Mr Chops, The Dwarf, originally devised for reading during a tour Dickens made in 1861.

Mr Chops is primarily light entertainment as a circus dwarf tries to move up in society after winning a lottery. Dr Marigold, however, is emotionally pure Dickens, with the novelist playing on the heart-strings with humour love, death, pathos, a good measure of bathos and, of course, a happy ending.

Advocates for disabled protest against film

Groups that advocate for the disabled called for a national boycott of the Ben Stiller comedy Tropic Thunder, citing what they say is its negative portrayal of people with intellectual disabilities.

"We are asking people not to go to the movie and hope to bring a consciousness to people about using derogatory words about this population," said Peter Wheeler, spokesman for Special Olympics, one of 22 disability groups nationwide protesting the satire.

The film, directed by Mr Stiller, will be released on Wednesday by Viacom Inc's Paramount Pictures and its DreamWorks unit.

The groups planned to picket the movie's premiere yesterday evening in Los Angeles's Westwood community.

Want to live a long life? Run

People who want to live a long and healthy life might want to take up running.

A study published yesterday shows middle-aged members of a runner's club were half as likely to die over a 20-year period as people who did not run.

Running reduced the risk not only of heart disease, but of cancer and neurological diseases such as Alzheimer's, researchers at Stanford University in California found.

"At 19 years, 15 per cent of runners had died compared with 34 per cent of controls," Eliza Chakravarty and colleagues wrote in the Archives of Internal Medicine.