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The finding was made by Brown University physicist Vesna Mitrovic and colleagues at Brown and in France.

At the quantum level, the forces of magnetism and superconductivity exist in an uneasy relationship.

Superconducting materials repel a magnetic field, so to create a superconducting current, the magnetic forces must be strong enough to overcome the natural repulsion and penetrate the body of the superconductor. This relationship is pretty well known. But why it is so remains mysterious. Now, physicists at Brown University have documented for the first time a quantum-level phenomenon that occurs to electrons subjected to magnetism in a superconducting material.

They report that at under certain conditions, electrons in superconducting material form odd, fluctuating magnetic waves.
Apply a little more magnetic force, and those fluctuations cease. The electronic magnets form repeated wave-like patterns promoted by superconductivity.

The discovery may help scientists understand more fully the relationship between magnetism and superconductivity at the quantum level.

The insight also may help advance research into superconducting magnets, which are used in magnetic resonance imaging (MRI) and a host of other applications.

When a magnetic field is applied to a superconducting material, vortices measured in nanometers (1 billionth of a meter) pop up.

These vortices, like super-miniature tornadoes, are areas where the magnetic field has overpowered the superconducting field state, essentially suppressing it.

Crank up the magnetic field and more vortices appear.

At some point, the vortices are so widespread the material loses its superconducting ability altogether.

At an even more basic level, sets of electrons called Cooper pairs form superconductivity. But, scientists believe there also are other electrons that are magnetically oriented and spin on their own axes like little globes.

These electrons are tilted at various angles on their imaginary axes and move in a repeating, linear pattern that resembles waves, Mitrovic and her colleagues have observed.

“These funny waves most likely appear because of superconductivity, but the reason why is still unsettled,” Mitrovic said. The researchers saw that the waves fluctuated under certain conditions.

Mitrovic and her colleagues also observed that when more magnetic energy is added, the fluctuations disappear and the waves resume their repeating, linear patterns.

The researchers next want to understand why these fluctuations occur and whether they crop up in other superconducting material.

ANI

Unearthed at a site in western Greenland, the hair provides a vivid portrait of a man who died four millennia ago and overturns a mainstream theory about how humans colonised the Arctic New World, they said.

Greenland’s first known settlers were not Inuit or Native Americans as widely believed, but the direct descendants of Siberians who somehow crossed the Bering Strait to Alaska and then headed east, according to their report, published by Nature.

The tuft of hair and four pieces of bone, uncovered at Qeqertasussuk, are the only human remains ever found of Saqqaq culture, an enigmatic coastal-dwelling community that lived in western Greenland for some 1,700 years.

Living on harp seals and fish and other marine food, the culture petered out around 800 BC, although the dates are uncertain.

University of Copenhagen researcher Eske Willerslev led a team that exhaustively analysed the precious Qeqertasussuk find.

They teased out nearly 80 percent of the genetic code and identified 353,151 single variations in DNA that are telltale signs of body characteristics.

“What we can see from the genomic data is a number of traits,” Willerslev told journalists in a teleconference.

“For example, we can see the guy had most likely brown eyes, brown skin, he had shovel-form front teeth and he had dry earwax, which increased the chance of getting infection in the ear,” said Willerslev.

“We can also see that he had a tendency to baldness and because we found quite a lot of hair from this guy we presume he actually died quite young, and we can see he was genetically adapted to cold temperatures, living in the Arctic.”

Yet the most surprising find came when the man’s genome was matched against those of people alive today.

His closest contemporaries are from Arctic eastern Siberia: ethnic groups called the Chukchis, the Koryaks and Naganasans — a finding also bolstered by a similar A+ blood group.

Anthropologists have long surmised that the first settlers to North America had either walked across the strait while it was iced over during the winter months, or crossed it by boat, perhaps using the Aleutian Islands as stepping stones.

These pioneers then headed south, with their descendants eventually arriving in the southern tip of South America thousands of years later.

Until now, Greenland was believed to have been settled by populations that headed there after prolonged settlement in the New World, such as Na-Dene people of North America, or the Inuit of the Arctic.

Willerslev, though, said that the Saqqaq man could be traced to Siberian peoples who had lived 200 generations before.

“It suggests an independent migration or expansion, if you wish, into the New World from the Old World some 5,500 years ago,” he said.

As to why the group should head towards Greenland, where it is permanently cold, rather than balmier climes farther south “is a good question,” he said.

PTI

The trading vessel was carrying an extremely valuable cargo of tin and hundreds of copper ingots from the Continent when it sank.

Experts say the ”incredibly exciting” discovery provides new evidence about the extent and sophistication of Britain’s links with Europe in the Bronze Age, and reveals the remarkable seafaring abilities of the people during the period.

Archaeologists have described the vessel, which is thought to date back to about 900BC, as being a ”bulk carrier” of its age. The copper and tin would have been used for making bronze, the primary product of the period which was used in the manufacture of weapons, tools, jewellery, ornaments and other items.

It is believed that the copper – and possibly the tin – were being imported into Britain and originated in a number of different countries throughout Europe, rather than from a single source, demonstrating the existence of a complex network of trade routes across the Continent. It is the first time tin ingots from this period have ever been found in Britain, a discovery which may support theories that the metal was being mined in the south-west at this time. If the tin was not produced in Britain, it is likely it would have come from the Iberian Peninsula or Germany.

The wreck was found in between eight and 10 metres of water in a bay near Salcombe, south Devon, by a team of amateur marine archaeologists from the South West Maritime Archaeological Group. In total, 295 artefacts have so far been recovered, weighing more than 84 kilograms.

The cargo recovered includes 259 copper ingots and 27 tin ingots. Also found was a bronze leaf sword, two stone artefacts that could have been slingshots, and three gold wrist torcs, or bracelets.

The team has yet to uncover any of the vessel’s structure, which is likely to have eroded away. But experts believe it would have been up to 12 metres long and up to 1.8 metres wide.

The artefacts are to be handed over to the British Museum next week. They will be independently valued and the museum will pay the team for the items.

ANI

A week before Christmas, Magnus Bladh of the Ottenby bird station, located on Öland’s southern cape, was strolling along the beach with a colleague when he saw something he’d never seen before.

“Temperatures were below freezing and there was a light wind, but it was very cold! In the seaweed we noticed at least 200 large ice balls,” he said in a report to Swedish meteorological agency SMHI.

“The balls varied in size but the biggest ones were quite large, some larger than a football.”

What mystified Bladh was that the balls were resting on the west side of a bed of seaweed, even though the prevailing winds were from the east.

When Bladh and his colleagues later broke open one of the ice balls, they discovered that it consisted of a 2 to 5 centimetre thick shell of ice, which covered a core of soft, wet snow.

According to SMHI, the ice balls likely form when rolls of light snow are blown from the shore into water which is at or just below freezing, but fails to form uniform ice due to strong winds.

The rolls of snow are then tossed about in the chilly waters, where wave action eventually shapes them into balls of ice.

“It’s hard to say just how common ice balls are, since we are reliant on witness reports,” SMHI spokeswoman Alexandra Ohlsson told The Local.

A review by SMHI of weather conditions on southern Öland in the days leading up to Bladh’s ice ball discovery revealed that temperatures in the area were generally below freezing, with snowfall, and winds from the north and northeast averaging 50 kilometres per hour.

According to SMHI, it was possible that rolls of snow near the shore remained soft due to warmth emanating up from the ground, which could have then been blown into the water by the strong winds.

Once formed, the balls likely came back to shore and, rather than floating out to open water, remained there due to a change in sea conditions in the days before the ice balls were discovered. Water levels sunk several decimetres between December 17th and December 18th when Bladh and his colleagues found the ice balls lying on the shore.

Beside’s Bladh’s discovery, SMHI’s website only mentions two other reported instances of ice balls being discovered in Sweden since the 1950s.

thelocal.se

A person’s heartbeat is controlled by electrical signals, which start in one central place – the heart’s pacemaker – and travel around the heart muscle.

And now, a team at Imperial College London have found the gene that controls those electrical signals and thus the rhythm of the heart.

The researchers claimed that the damage or mutations to the gene – known as SCN10A – increase the risk of heart disease.

The researchers believe that the finding could help them to understand how the body’s heartbeat is controlled and could ultimately help them come up with new treatments for heart rhythm disturbances.

It is also hoped that studying different variations of the gene in different people will help doctors discover why some people are more susceptible to heart trouble than others.

“Genetic variation is like the two sides of a coin. One side is associated with increased risk, the other with decreased risk. We have identified a gene that influences heart rhythm, and people with different variants of the gene will have increased or decreased risks of developing heart rhythm problems,” the Telegraph quoted Dr John Chambers, lead author of the study as saying.

In the study, the researchers analysed the genetic make-up of almost 20,000 people to look for genetic factors influencing the heartbeat.

They studied the electrocardiogram (ECG, a recording of the heartbeat) of each person, and measured the time taken for electrical signals to travel to different parts of the heart.

They found that variation in the gene SCN10A was linked with slow and irregular heart rhythms, including risk of ventricular fibrillation.

ANI