The eight-second scan that can detect breast cancer... using anti-landmine technology

By Jenny Hope

British scientists have created a revolutionary breast-screening system using anti-landmine technology that can detect cancer in seconds.

The pain-free radio-wave scanner is safer than traditional mammogram X-rays, which carry a radiation risk and are used on hundreds of thousands of women every year.

Experts believe the new device, which is also cheaper, can be used on women of any age, unlike current technology.

It is expected the system, called Maria, will be in widespread use within five years in GPs’ surgeries and clinics.

Women under 50 are not routinely screened for breast cancer partly because of the risks from regular doses of ionising radiation from an early age. They also have denser breast tissue, which makes it harder to detect tumours using X-rays.

Using radio waves makes it easier to find problems in all tissue.

But the most appealing aspect for women is pain-free examinations, with an end to having the breast squeezed between two X-ray plates.

Instead, the breast is held in a ceramic cup-shaped scanner while data are transferred to a computer within eight seconds to produce a 3D image.

Conventional screening uses low-dose X-rays and two scans are taken of the breast, during which the technician has to shelter from the radiation.

It takes an average of one minute for a radiologist to examine a case, but this can be more than doubled if another opinion is sought or the X-ray is difficult to interpret. Women are usually informed of the result within two weeks.

Developed by Micrima, a company that began at Bristol University, the Maria technology is based on a landmine-detection project that was able to locate non-metallic explosives in soil.

In the same way, the Maria system can find dangerous ‘hot spots’ in breasts using scanning signals from radio waves.

They register differences between normal breast tissue and a collection of blood and water contained in a tumour.

In pilot studies on 200 women, the system picked up about 80 per cent of tumours – a success rate close to existing techniques.

The latest phase of tests on Maria (Multistatic Array Processing for Radiowave Image Acquisition) took place at Frenchay Hospital’s Breast Care Centre in Bristol, and the city’s Southmead Hospital.

Dr Mike Shere, breast specialist at Southmead Hospital, said: ‘We are very excited about the potential of this completely new method of breast imaging.

‘It has none of the disadvantages of the current methods – ultrasound, mammography and MRI. It is quick, safe, comfortable and cheap, and is already producing good images with high sensitivity. This technology uses radio waves which are almost exactly the same as mobile phone frequency – and less energy. It is completely safe, unlike mammography, where there is an increasing cancer risk when women have more X-rays.

‘And it’s much more comfortable for women, some of whom may be deterred from screening at present because they find it painful.’

The women in the pilot study, who had already been diagnosed with breast cancer through X-rays, ultrasound or detection of a lump, were double-checked using the new system. In four out of five cases, the tumour was identified and clinicians expect the rate to increase to 90 per cent.

The technique uses an innovative radar system developed by a team at Bristol University, led by Professor Ian Craddock and Professor Alan Preece.

Cancer fears over 50,000 women in Britain who have had breast implant surgery

Alert follows death of French woman who had implants with silicone gel 'made for mattresses'

By Fiona Macrae

Tens of thousands of women with breast implants are being urged to have medical check-ups amid fears they are at heightened risk of cancer.

The safety alert follows the death of a French woman who had implants filled with silicone gel believed to have been made for mattresses.

Up to 50,000 British women – including some breast cancer survivors – have the French-made implants, which are fragile and more likely to leak than other brands.

Fears about the safety of Poly Implants Prothèses – or PIPs – which were among the cheapest implants on the market, first surfaced 18 months ago.

However, they receded after tests failed to find any firm evidence that the implants could trigger cancer.

Now, the death of 53-year-old Edwige Ligoneche, in a Marseille cancer clinic, from a rare form of cancer, has reignited concern.

Although the link with the implants hasn’t been established, it is feared that the gel leaked out of her breasts and into her system.

The French Society of Reconstructive and Aesthetic Plastic Surgeons says the gel could have been an ‘aggravating factor’ in the cancer.
It is reviewing its policy on the implants.

Their British counterparts have urged women not to worry – but say that patients who have, or suspect they have these implants, should have regular scans to check for flaws and cracks.

If there are signs of damage, implants on both sides should be removed.

Some GPs may be happy to refer women for an ultrasound, otherwise they will have to pay for it privately.

The NHS does take out damaged implants but won’t pay for new ones to be put in, meaning patients could be left with a bill that runs into thousands of pounds – as well as the trauma of additional surgery.

The alarm was first raised in France after surgeons noticed that PIP implants were rupturing much more quickly than other more expensive brands.

An inquiry ordered by the French health watchdog reported ‘serious’ irregularities in the implants last summer.

Among other things, when the gel’s manufacturer was asked for studies on its safety, it said it did not have any – because it believed it was to be used in the manufacture of mattresses.

In 2009, the French government agency responsible for medical equipment safety standards, Afssaps, received a number of complaints about the PIP implants.

How animals predict earthquakes

By Victoria Gill Science reporter, BBC Nature

Animals may sense chemical changes in groundwater that occur when an earthquake is about to strike.

This, scientists say, could be the cause of bizarre earthquake-associated animal behaviour.

Researchers began to investigate these chemical effects after seeing a colony of toads abandon its pond in L'Aquila, Italy, in 2009 - days before a quake.

They suggest that animal behaviour could be incorporated into earthquake forecasting

The team's findings are published in the International Journal of Environmental Research and Public Health. In this paper, they describe a mechanism whereby stressed rocks in the Earth's crust release charged particles that react with the groundwater.

Animals that live in or near groundwater are highly sensitive to any changes in its chemistry, so they might sense this days before the rocks finally "slip" and cause a quake.

The team, led by Friedemann Freund from Nasa and Rachel Grant from the UK's Open University hope their hypothesis will inspire biologists and geologists to work together, to find out exactly how animals might help us recognise some of the elusive signs of an imminent earthquake.

Strange behaviour

The L'Aquila toads are not the first example of strange animal behaviour before a major seismic event. There have been reports throughout history of reptiles, amphibians and fish behaving in unusual ways just before an earthquake struck.

In 1975, in Haicheng, China, for example, many people spotted snakes emerging from their burrows a month before the city was hit by a large earthquake.

This was particularly odd, because it occurred during the winter. The snakes were in the middle of their annual hibernation, and with temperatures well below freezing, venturing outside was suicide for the cold-blooded reptiles.

But each of these cases - of waking reptiles, fleeing amphibians or deep-sea fish rising to the surface - has been an individual anecdote. And major earthquakes are so rare that the events surrounding them are almost impossible to study in detail.

This is where the case of the L'Aquila toads was different.

Toad exodus

Ms Grant, a biologist from the Open University, was monitoring the toad colony as part of her PhD project.

"It was very dramatic," she recalled. "It went from 96 toads to almost zero over three days."

Ms Grant published her observations in the Journal of Zoology.

"After that, I was contacted by Nasa," she told BBC Nature.

Scientists at the US space agency had been studying the chemical changes that occur when rocks are under extreme stress. They wondered if these changes were linked to the mass exodus of the toads.

Their laboratory-based tests have now revealed, not only that these changes could be connected, but that the Earth's crust could directly affect the chemistry of the pond that the toads were living and breeding in at the time.

Nasa geophysicist Friedemann Freund showed that, when rocks were under very high levels of stress - for example by the "gargantuan tectonic forces" just before an earthquake, they release charged particles.

These charged particles can flow out into the surrounding rocks, explained Dr Freund. And when they arrive at the Earth's surface they react with the air - converting air molecules into charged particles known as ions.

"Positive airborne ions are known in the medical community to cause headaches and nausea in humans and to increase the level of serotonin, a stress hormone, in the blood of animals," said Dr Freund. They can also react with water, turning it into hydrogen peroxide.

This chemical chain of events could affect the organic material dissolved in the pond water - turning harmless organic material into substances that are toxic to aquatic animals.

It's a complicated mechanism and the scientists stress that it needs to be tested thoroughly.

But, Dr Grant says this is the first convincing possible mechanism for a "pre-earthquake cue" that aquatic, semi-aquatic and burrowing animals might be able to sense and respond to.

"When you think of all of the many things that are happening to these rocks, it would be weird if the animals weren't affected in some way," she said.

Dr Freund said that the behaviour of animals could be one of a number of connected events that might forecast an earthquake.

"Once we understand how all of these signals are connected," he told BBC Nature, "if we see four of five signals all pointing in [the same] direction, we can say, 'ok, something is about to happen'."

Could scientists reverse global warming? The U.N. discusses plans to reflect the sun to cool the Earth

By Paul Milligan

Last updated at 2:51 AM on 3rd December 2011

A group of scientists, philosophers and legal scholars are looking into radical geoengineering plans to artificially cool the Earth in a bid to reverse global warning.

A U.N. climate conference in South Africa on Friday said that - in theory - reflecting a small amount of sunlight back into space before it strikes the Earth's surface would have an immediate and dramatic effect.

Within a few years, global temperatures could return to levels of 250 years ago, before the industrial revolution began dumping carbon dioxide into the air, trapping heat and causing temperatures to rise.

But no one knows what the side effects would be.

They could unintentionally changing weather patterns and rainfall.

The idea of solar radiation management ‘has the potential to be either very useful or very harmful,’ said the study led by Britain's Royal Society, the Washington-based Environmental Defense Fund and TWAS, the academy of sciences for the developing world based in Trieste, Italy.

The final report is the climax of a year-long dialogue spanning experts in 22 countries.

It was prompted by the failure of a 20-year U.N. negotiating process to take decisive action to curb greenhouse gas emissions, mainly from burning fossil fuels, responsible for climate change.

'The slow progress of international climate negotiations has led to increased concerns that sufficient cuts in greenhouse gas emissions may not be achieved in time to avoid unacceptable levels of climate change,' the report said.

But geoengineering is not an alternative to climate action, said John Shepherd, a British oceanographer from the University of Southampton who was the lead author of the report.

'Nobody thought this provides a justification for not reducing carbon emissions,' Shepherd told AP.

'We have to stick with Plan A for the time being, and that could be a very long time indeed,' he said. 'This would buy time for people to make the transition to a low-carbon economy.'

The Intergovernmental Panel on Climate Change sees temperatures rising as much as 6.4 degrees Celsius (11.5 degrees Fahrenheit) by 2100, swelling the seas with melted glacial water and disrupting climate conditions around the globe.

Deliberately tinkering with nature to counter global warming can only be a stopgap measure, and is fraught with danger, the report said.

Action such as spraying sulfur into the air or brightening clouds with sea water to reflect more sunlight would have to be sustained indefinitely because 'there would be a large and rapid climate change if it were terminated suddenly,' the report said.

Theories of manipulating the climate to impede global warming have been on the fringe of scientific discussion for some time, but is now moving towards the mainstream.

In the United States, a group of 18 U.S. experts from the sciences, social sciences and national security unveiled a report in October urging the federal government to begin research on the feasibility and potential effectiveness of geoengineering.

Gigantic black hole chews up a star and scientists watch it for the first time

• Astronomers watch as Nasa telescope captures rare event
• Phenomenon only occurs once every 100million years
• Radiation from the event travelled for 3.9billion years before reaching Earth
  

By Ted Thornhill

One of the rarest events in the universe has been seen by scientists for the first time.

A stunning cosmic jet from a super-massive black hole which shredded then swallowed a star has been observed by astronomers. Known as 'relativistic jets', they can reach hundreds of thousands of light years in length.

The swallowing of a star by a black hole only happens once every one hundred million years in a galaxy.

SCROLL DOWN FOR VIDEO

Most galaxies have super-massive black holes - regions of space that suck in everything nearby with their strong gravitation pull - at their core, with masses of millions or even billions of suns.

Scientists were first alerted to the phenomenon in March after Nasa's Swift telescope detected several bursts of X-rays from a quiet patch of sky.

Teams from both Pennsylvania State University and the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, said the bursts could be the remnants of a star pulled apart when it came too close to a black hole located 3.9billion light years away.

Dr David Burrows, from Pennsylvania State University which controls Swift, said chemical analysis of the bright flash's ultraviolet light show it comes from material being sucked into a black hole the size of a million suns.

Writing in Nature, they concluded that the Swift satellite just happened to be in the path of the jet of star remains that were shot out at 99.5 per cent the speed of light.

Dr Burrows said: 'Incredibly, this source is still producing X-rays and may remain bright enough for the Swift satellite to observe into next year. It behaves unlike anything we've seen before.'

The black hole is now believed to be even more powerful because of the additional mass from the swallowed star.

The absorption of large mass such as stars or even other black holes is what gives black holes growth and spawn the existence of super-massive black holes.Super-massive black holes could contain up to billions of solar masses.

By comparison, the sun is just one solar mass and the Earth is 1/332,950th of a solar mass.

Black holes are probably the strangest cosmic phenomenon that we know about.

Their gravity is so strong that normal laws of physics just don't apply, with time actually slowing down at a black hole's event horizon - the point at which it would be impossible to escape its clutches.

Read more: http://www.dailymail.co.uk/sciencetech/article-2068474/Gigantic-black-hole-chews-star-scientists-watch-time.html#ixzz1fU1mA5Su

The death star: Astronomers catch final moments before supernova strikes

By Rob Waugh

In summer this year, a fairly nondescript star system in the Whirpool galaxy suddenly caught astronomers' attention - it went supernova.

But scientists had already been watching - the researchers have been scanning 25 nearby galaxies for stars that brighten and dim in unusual ways, in order to catch a few that are about to meet their end.

They saw one star in this binary system dim noticeably before the other one exploded in a supernova - which might provide a 'litmus test' for predicting future explosions.

The study, submitted in a paper to the Astrophysical Journal, provides the latest result from an Ohio State University galaxy survey underway with the Large Binocular Telescope, located in Arizona.

In the first survey of its kind, the researchers have been scanning 25 nearby galaxies for stars that brighten and dim in unusual ways, in order to catch a few that are about to meet their end.

In the three years since the study began, this particular unnamed binary system in the Whirlpool Galaxy was the first among the stars they’ve cataloged to produce a supernova.

Though they’re still sorting through the data, it’s likely that they didn’t get any direct observations of the star that exploded – only its much brighter partner.

Yet, principal investigator Christopher Kochanek, professor of astronomy at Ohio State and the Ohio Eminent Scholar in Observational Cosmology, does not regard this first result as a disappointment. Rather, it’s a proof of concept.

'Our underlying goal is to look for any kind of signature behavior that will enable us to identify stars before they explode,' he said. 'It’s a speculative goal at this point, but at least now we know that it’s possible.'

'Maybe stars give off a clear signal of impending doom, maybe they don’t,' said study co-author Krzystof Stanek, professor of astronomy at Ohio State, “But we’ll learn something new about dying stars no matter the outcome.'

Postdoctoral researcher Dorota Szczygiel, who led the study of this supernova, explained why the galaxy survey is important.

“The odds are extremely low that we would just happen to be observing a star for several years before it went supernova. We would have to be extremely lucky,” she said.

'With this galaxy survey, we’re making our own luck. We’re studying all the variable stars in 25 galaxies, so that when one of them happens go supernova, we’ve already compiled data on it.'

As astronomers gather data from more supernovae – Kochanek speculates that as many as one per year could emerge from their data set – they could assemble a kind of litmus test to predict whether a particular star is near death.
The team won’t be watching our sun for any changes, however. At less than 10 percent of the mass of the star in supernova 2011dh, our star will most likely meet a very boring end.

'There’ll be no supernova for our sun – it’ll just fizzle out,' Kochanek said. 'But that’s okay – you don’t want to live around an exciting star.'

Read more: http://www.dailymail.co.uk/sciencetech/article-2068760/The-death-star-Astronomers-catch-final-moments-star-supernova-strikes.html#ixzz1fU0TyeTD

The Milky Way is 'still hungry' - how our galaxy keeps devouring its smaller neighbours

By Rob Waugh

Last updated at 2:56 PM on 2nd December 2011

The Milky Way bar was always advertised as the chocolate bar that you could eat without filling you up.

But the galaxy after which it's named - our own - has an insatiable appetite.

It's still devouring neighbouring dwarf galaxies at a frightening rate - and astronomers recently captured two 'streams' of stars 'torn off' a nearby dwarf galaxy into our own.

A team of astronomers led by Sergey Koposov and Vasily Belokurov of the University of Cambridge recently discovered two streams of stars in the Southern Galactic hemisphere that were torn off the Sagittarius dwarf galaxy.

'We have long known that when small dwarf galaxies fall into bigger galaxies, elongated streams, or tails, of stars are pulled out of the dwarf by the enormous tidal field,' said Sergey Koposov.

The Sagittarius dwarf galaxy used to be one of the brightest of the Milky Way satellites. Its disrupted remnant now lies on the other side of the Galaxy, breaking up as it is crushed and stretched by huge tidal forces.

It is so small that it has lost half of its stars and all its gas over the last billion years.

Read more: http://www.dailymail.co.uk/sciencetech/article-2069161/The-Milky-Way-hungry--galaxy-keeps-devouring-smaller-neighbours.html#ixzz1fTzLt5Iq

Earth's Inconstant Magnetic Field

December 29, 2003: Every few years, scientist Larry Newitt of the Geological Survey of Canada goes hunting. He grabs his gloves, parka, a fancy compass, hops on a plane and flies out over the Canadian arctic. Not much stirs among the scattered islands and sea ice, but Newitt's prey is there--always moving, shifting, elusive.

His quarry is Earth's north magnetic pole.

At the moment it's located in northern Canada, about 600 km from the nearest town: Resolute Bay, population 300, where a popular T-shirt reads "Resolute Bay isn't the end of the world, but you can see it from here." Newitt stops there for snacks and supplies--and refuge when the weather gets bad. "Which is often," he says.

Right: The movement of Earth's north magnetic pole across the Canadian arctic, 1831--2001. Credit: Geological Survey of Canada. [more]

Scientists have long known that the magnetic pole moves. James Ross located the pole for the first time in 1831 after an exhausting arctic journey during which his ship got stuck in the ice for four years. No one returned until the next century. In 1904, Roald Amundsen found the pole again and discovered that it had moved--at least 50 km since the days of Ross.

The pole kept going during the 20th century, north at an average speed of 10 km per year, lately accelerating "to 40 km per year," says Newitt. At this rate it will exit North America and reach Siberia in a few decades.

Keeping track of the north magnetic pole is Newitt's job. "We usually go out and check its location once every few years," he says. "We'll have to make more trips now that it is moving so quickly."

Earth's magnetic field is changing in other ways, too: Compass needles in Africa, for instance, are drifting about 1 degree per decade. And globally the magnetic field has weakened 10% since the 19th century. When this was mentioned by researchers at a recent meeting of the American Geophysical Union, many newspapers carried the story. A typical headline: "Is Earth's magnetic field collapsing?"

Probably not. As remarkable as these changes sound, "they're mild compared to what Earth's magnetic field has done in the past," says University of California professor Gary Glatzmaier.

Sometimes the field completely flips. The north and the south poles swap places. Such reversals, recorded in the magnetism of ancient rocks, are unpredictable. They come at irregular intervals averaging about 300,000 years; the last one was 780,000 years ago. Are we overdue for another? No one knows.

Left: Magnetic stripes around mid-ocean ridges reveal the history of Earth's magnetic field for millions of years. The study of Earth's past magnetism is called paleomagnetism. Image credit: USGS. [more]

According to Glatzmaier, the ongoing 10% decline doesn't mean that a reversal is imminent. "The field is increasing or decreasing all the time," he says. "We know this from studies of the paleomagnetic record." Earth's present-day magnetic field is, in fact, much stronger than normal. The dipole moment, a measure of the intensity of the magnetic field, is now 8 × 10²² amps × m². That's twice the million-year average of 4× 10²² amps × m².

To understand what's happening, says Glatzmaier, we have to take a trip ... to the center of the Earth where the magnetic field is produced.

At the heart of our planet lies a solid iron ball, about as hot as the surface of the sun. Researchers call it "the inner core." It's really a world within a world. The inner core is 70% as wide as the moon. It spins at its own rate, as much as 0.2° of longitude per year faster than the Earth above it, and it has its own ocean: a very deep layer of liquid iron known as "the outer core."

Right: a schematic diagram of Earth's interior. The outer core is the source of the geomagnetic field.

Earth's magnetic field comes from this ocean of iron, which is an electrically conducting fluid in constant motion. Sitting atop the hot inner core, the liquid outer core seethes and roils like water in a pan on a hot stove. The outer core also has "hurricanes"--whirlpools powered by the Coriolis forces of Earth's rotation. These complex motions generate our planet's magnetism through a process called the dynamo effect.

Using the equations of magnetohydrodynamics, a branch of physics dealing with conducting fluids and magnetic fields, Glatzmaier and colleague Paul Roberts have created a supercomputer model of Earth's interior. Their software heats the inner core, stirs the metallic ocean above it, then calculates the resulting magnetic field. They run their code for hundreds of thousands of simulated years and watch what happens.

What they see mimics the real Earth: The magnetic field waxes and wanes, poles drift and, occasionally, flip. Change is normal, they've learned. And no wonder. The source of the field, the outer core, is itself seething, swirling, turbulent. "It's chaotic down there," notes Glatzmaier. The changes we detect on our planet's surface are a sign of that inner chaos.

They've also learned what happens during a magnetic flip. Reversals take a few thousand years to complete, and during that time--contrary to popular belief--the magnetic field does not vanish. "It just gets more complicated," says Glatzmaier. Magnetic lines of force near Earth's surface become twisted and tangled, and magnetic poles pop up in unaccustomed places. A south magnetic pole might emerge over Africa, for instance, or a north pole over Tahiti. Weird. But it's still a planetary magnetic field, and it still protects us from space radiation and solar storms.

Above: Supercomputer models of Earth's magnetic field. On the left is a normal dipolar magnetic field, typical of the long years between polarity reversals. On the right is the sort of complicated magnetic field Earth has during the upheaval of a reversal. [more]

And, as a bonus, Tahiti could be a great place to see the Northern Lights. In such a time, Larry Newitt's job would be different. Instead of shivering in Resolute Bay, he could enjoy the warm South Pacific, hopping from island to island, hunting for magnetic poles while auroras danced overhead.

Sometimes, maybe, a little change can be a good thing.