'Safe' climate means 'no to coal'

Coal must either modernise or become obsolete, the research implies

More than 100 nations support the goal of keeping temperature rise below 2C.

But the scientists say that without major curbs on fossil fuel use, 2C will probably be reached by 2050.

Writing in Nature, they say politicians should focus on limiting humanity's total output of CO2 rather than setting a "safe" level for annual emissions.

The UN climate process focuses on stabilising annual emissions at a level that would avoid major climate impacts.

But this group of scientists says that the cumulative total provides a better measure of the likely temperature rise, and may present an easier target for policymakers.

"To avoid dangerous climate change, we will have to limit the total amount of carbon we inject into the atmosphere, not just the emission rate in any given year," said Myles Allen from the physics department at Oxford University.

"Climate policy needs an exit strategy; as well as reducing carbon emissions now, we need a plan for phasing out net emissions entirely."

Forty years

The UN climate convention, agreed at the 1992 Rio Earth Summit, commits countries to avoiding "dangerous" climate change, without defining what that is.

The EU proposed some years ago that restricting the rise to 2C from pre-industrial times was a reasonable threshold, and it has since been adopted by many other countries, although some - particularly small islands - argue that even 2C would result in dangerous impacts.

Temperatures have already risen by about 0.7C during the industrial age.

Dr Allen's analysis suggests that if humanity's CO2 emissions total more than about one trillion tonnes of carbon, the 2C threshold is likely to be breached; and that could come within a lifetime.

"It took us 250 years to burn the first half trillion," he said, "and on current projections we'll burn the next half trillion in less than 40 years."

Inherent uncertainties in the modelling mean the temperature rise from the trillion tonnes could be between 1.3C and 3.9C, Dr Allen's team calculates, although the most likely value would be 2C.

Oil change

The "trillion tonnes" analysis is one of two studies published in Nature by a pool of researchers that includes the Oxford group and scientists from the Potsdam Institute for Climate Change Impact Research in Germany.

Impacts such as droughts would increase above 2C, the IPCC believes

The second study, led by Potsdam's Malte Mainshausen, attempted to work backwards from the 2C goal, to find out what achieving it might mean in practice.

It suggests that the G8 target of halving global emissions by 2050 (from 1990 levels) would leave a significant risk of breaching the 2C figure.

"Only a fast switch away from fossil fuels will give us a reasonable chance to avoid considerable warming," said Dr Mainshausen.

"If we continue burning fossil fuels as we do, we will have exhausted the carbon budget in merely 20 years, and global warming will go well beyond 2C."

If policymakers decided they were happy to accept a 25% chance of exceeding 2C by 2050, he said, they must also accept that this meant cutting emissions by more than 50%.

That would mean only burning about a quarter of the carbon in the world's known, economically-recoverable fossil fuel reserves. This is likely to consist mainly of oil and natural gas, leaving coal as a redundant fuel unless its emissions could be captured and stored.

Both analyses support the view of the Stern Review and the Intergovernmental Panel on Climate Change (IPCC) in suggesting that making reductions earlier would be easier and cheaper than delaying.

But according to Potsdam's Bill Hare, a co-author on the second paper, some key governments appear to favour pledging milder cuts in the near term in return for more drastic ones in decades to come.

"We have a number of countries - the US, Japan, Brazil - saying 'we will emit higher through to 2020 and then go down faster'," he said.

"That might be true geophysically, but we cannot find any economic model where emissions can fall in the range that this work shows would be necessary - around 6% per year."

Major intervention

Myles Allen's group has made the argument before that focussing on humanity's entire carbon dioxide output makes more scientific and political sense than aiming to define a particular "safe" level of emissions, or to plot a pathway assigning various ceilings to various years.

Some greenhouse gases, such as methane, have a definable lifetime in the atmosphere, meaning that stabilising emissions makes sense; but, said Dr Allen, CO2 "doesn't behave like that".

"There are multiple levers acting on its concentration and it does tend to accumulate; also models have to represent the possibility of some feedback between rising temperatures and emissions, such as parts of the land turning from carbon sinks into sources, for example."

The Nature papers emerge in a week that has seen the inaugural meeting of President Obama's Major Economies Forum on Energy and Climate, a new version of a body created under President Bush that brings together 17 of the world's highest-emitting countries for discussion and dialogue.

During the opening segment, Secretary of State Hillary Clinton re-affirmed the administration's aim of cutting US emissions by 80% from 1990 levels by 2050 - a target espoused by some other developed countries.

But according to Malte Meinshausen's analysis, even this reduction may not be enough to keep the average global temperature rise within 2C, assuming less developed nations made less stringent cuts in order to aid their development.

"If the US does 80%, that equates to about 60% globally, and that offers only a modest chance of meeting the 2C target," he said.

Last week saw the publication of data showing that industrialised countries' collective emissions rose by about 1% during 2007.

Debut for world's fastest camera

The technique hinges on an ordered spreading of the colours in laser light

Their camera snaps images less than a half a billionth of a second long, capturing over six million of them in a second continuously.

It works by using a fast laser pulse dispersed in space and then stretched in time and detected electronically.

The approach will be instrumental in analysing, for example, flowing blood samples in a search for diseased cells.

What is more, the camera works with just one detector, rather than the millions in a typical digital camera.

Gathering steam

Dubbed Serial Time-Encoded Amplified imaging, or Steam, the technique depends on carefully manipulating so-called "supercontinuum" laser pulses.

These pulses, less than a millionth of a millionth of a second long, contain an enormously broad range of colours.

Two optical elements spread the pinprick laser pulses into an ordered two-dimensional array of colours.

It is this "2-D rainbow" that illuminates a sample. Part of the rainbow is reflected by the sample - depending on light and dark areas of the illuminated spot - and the reflections travel back along their initial path.

Because the spreading of the pulse's various colours is so regular and ordered, the range of colours reflected contains detailed spatial information about the sample.

"Bright spots reflect their assigned wavelength but dark ones don't," explained Bahram Jalali, the University of California, Los Angeles professor who led the research.

Our next step is to improve the spatial resolution so we can take crystal clear pictures of the inner structure of cells Bahram Jalali, UCLA

"When the 2-D rainbow reflects from the object, the image is copied onto the colour spectrum of the pulse."

The pulse then passes back through the dispersive optics and again becomes a pinprick of light, with the image tucked away within as a series of distributed colours.

However, that colour spectrum is mixed up in an exceptionally short pulse of light that would be impossible to unpick in traditional electronics.

The team then routes the pulse into a so-called dispersive fibre - a fibre-optic cable that has a different speed limit for different colours of light.

As a result, the red part of the spectrum races ahead of the blue part as the pulse travels along the fibre.

Eventually, the red part and blue part separate in the fibre, arriving at very different times at the fibre's end.

All that remains is to detect the light as it pops out of the fibre with a standard photodiode and digitise it, assigning the parts of the pulse that arrive at different times to different points in two-dimensional space.

The result of all this optical trickery: an image that represents a snapshot just 440 trillionths of a second long.

The researchers used a laser that fired more than six million pulses in a second, resulting in as many images. However, they say that the system can be improved to acquire more than 10 million images per second - more than 200,000 times faster than a standard video camera.

'Rogue cells'

Instead of the millions of detectors in a digital camera, Steam uses just one

While other cameras used in scientific research can capture shorter-lived images, they can only capture about eight images, and have to be triggered to do so for a given event.

The Steam camera, by contrast, can capture images continuously, making it ideal for random events that cannot be triggered.

Some applications that may benefit from the approach include observing the communication between cells, or the activity of neurons.

But the perfect example of an application for the Steam camera's specifications is analysing flowing blood samples.

Because the imaging of individual cells in a volume of blood is impossible for current cameras, a small random sample is taken and those few cells are imaged manually with a microscope.

"But, what if you needed to detect the presence of very rare cells that, although few in number, signify early stages of a disease?," asks Keisuke Gode, lead author of the study.

Dr Gode cites circulating tumour cells as a perfect example of such a target. Precursors to metastasis, they may exist as only a few among a billion healthy cells.

"The chance that one of these cells will happen to be on the small sample of blood viewed under a microscope is virtually negligible."

But with the Steam camera, fast-flowing cells can be individually imaged.

The team is working to extend the technique to 3-D imaging with the same time resolution, and to increase the effective number of "pixels" in a given image to 100,000.

"Our next step is to improve the spatial resolution so we can take crystal clear pictures of the inner structure of cells," Professor Jalali told BBC News.

"We are not there yet, but if we are able to accomplish this, then there is no shortage of applications in biology."

Russia mulls rocket power 'first'

The future Russian capsule could land on a bright rocket plume

Russia's next-generation manned space vehicle might be equipped with thrusters to perform a precision landing on its return to Earth.

Engineers are considering a rocket-powered landing system for the successor to Russia's Soyuz spacecraft.

If accepted, it would be the first time in history that a manned vehicle relied solely on rocket engines for touchdown.

Previous manned missions have landed on Earth using a parachute or, in the case of space shuttles, a pair of wings.

RKK Energia, Russia's prime developer of manned spacecraft, had to examine the feasibility of the rocket-powered landing as a result of conflicting requirements for the project set by the Russian government.

Currently, Russian cosmonauts are carried into orbit on the three-seat Soyuz capsule. Russia is developing the new craft as a replacement to this venerable spacecraft, which has been in service for more than four decades.

The Soyuz does use small solid propellant motors to soften its touchdown, but the ship's parachute plays the main role in providing the vehicle and crew with a safe landing.

New launch site

In 2007, Moscow took the momentous decision to build a new launch site in the nation's far east, hoping to end Russia's dependency on the spaceport in Baikonur, which, after the collapse of the Soviet Union, ended up in the newly independent republic of Kazakhstan.

The new site, which has been dubbed Vostochny, or simply "Eastern", will be located almost as far south as Baikonur - an important orbital mechanics factor which determines the cargo-carrying capacity of rockets.

However, the very same decision left only a narrow strip of land in the European part of Russia, near the city of Orenburg, where returning space capsules could touch down if they followed a straight ballistic trajectory.

Not surprisingly, Russian engineers found themselves under political pressure to improve the manoeuvrability of the future spacecraft, so it could guide itself into a relatively small landing area.

The alternative - landing under a parachute - would put the craft at the mercy of the wind.

Radical solutions like gliding wingless vehicles and "transformers" with deployable wings were deemed too expensive and technically risky giving the Kremlin's current requirement to have the new spacecraft ready for its first manned mission in 2018.

Eventually, the idea for a rocket-assisted landing emerged as a winner, promising to keep the predicted touchdown to a patch of land of only two by five kilometres.

The new ship would be launched towards the end of the next decade

Last July, Korolev-based RKK Energia released the first drawings of a multi-purpose transport ship, known as the Advanced Crew Transportation System (ACTS), which, at the time, Russia had hoped to develop in co-operation with Europe.

But the design of the spacecraft's crew capsule had raised eyebrows in some quarters, as it lacked a parachute - instead sporting a cluster of 12 soft-landing rockets, burning solid propellant.

Combined with retractable landing legs and a re-usable thermal protection system, landing rockets promised to enable not only a safe return to Earth, but also the possibility of performing multiple space missions with the same crew capsule.

According to the presentation made by Nikolai Bryukhanov, the leading designer at RKK Energia, at the 26th International Symposium on Space Technology and Science in Hamamatsu, Japan, the spacecraft would fire its engines at an altitude of just 600-800m, as the capsule is streaking toward Earth after re-entering the atmosphere at the end of its mission.

After a vertical descent, the precision landing would be initiated at the altitude of 30m above the surface.

Christian Bank, the leading designer of manned space systems at EADS-Astrium in Bremen, Germany, which at the time was responsible for the European side of the ACTS project, agreed with the validity of this novel Russian approach toward landing.

"It was explained to us how it was supposed to work and, I think, from the technical point of view, there is no doubt that this concept would work," Mr Bank told BBC News.

However, inside Russia, the idea apparently has many detractors. Since the end of 2008, Moscow has shrouded the new manned spacecraft project - now known by the Russian abbreviation PPTS, for Prospective Piloted Transport System - in a veil of secrecy.

But hints dropped by Russian officials and in anonymous postings on industry web forums have provided insights into a vigorous debate on the landing system raging within the Russian space industry.

Controversial system

In April 2009, the semi-official RIA Novosti news agency quoted an unnamed RKK Energia official as saying that the future spacecraft would use an environmentally-friendly liquid propellant - such as alcohol - during its touchdown.

The use of liquid propellants would also enable more control during landing thanks to variable thrust, while solid fuel would burn according to a pre-determined profile once it had been ignited.

The Zarya project fell through just before the collapse of the Soviet Union

Still, the switch to a liquid propellant did not silence the critics, who regard any rocket engines too complex and risky to rely on in the last minutes or seconds before touching down.

As a result, an alternative concept has emerged, which would combine a high-precision rocket-powered landing under normal circumstances and a parachute in the case of an emergency.

As with any compromise, it requires splitting the capsule into two parts - the crew cabin and the propulsion section.

If the craft's landing engines were to fail, the propulsion section would have to be jettisoned. Otherwise, the propellant-laden ship would be too heavy for a parachute to handle.

As preliminary development of the PPTS vehicle would not be completed until mid-2010, only time will tell whether this compromise can silence the system's detractors.

Track record

RKK Energia did not begin its work for the rocket-powered landing system on a blank sheet of paper. In the 1980s, the company worked on a highly classified project to develop a large manned capsule, called Zarya ("Dawn"), for a wide range of civilian and military missions.

The bell-shaped vehicle was to use liquid propellant rockets for returning to Earth. Zarya was in an advanced stage of design when the project was shelved in 1989 on the eve of the Soviet Union's collapse.

The US had a similar idea for its DC-X experimental vehicle

Back then, the concept of a rocket-powered landing also produced plenty of controversy.

During the formal defence of the project, one high-ranking official sceptical of the rocket-cushioned approach to landing reportedly used an unprintable expletive to describe what was going to happen to crew members unlucky enough to encounter a rocket engine failure a few seconds before touchdown.

But if a rocket-powered landing was ever to be adopted for Russia's next-generation manned spacecraft, it would not be the first space vehicle to use such a system.

In the 1990s, the US tested an unmanned prototype of a re-usable launcher, know as DC-X, which would lift off and land vertically under rocket power.

Conceived primarily for the needs of the US Star Wars missile defence programme, DC-X was abandoned after the end of the Cold War.

Security cameras clue to fireball

The light in the sky is thought to have been a shooting star

The shooting star was reported at about 1230 BST by people living as far apart as Donegal and Cork.

David Moore chairman of Astronomy Ireland said they were fairly certain it was a rock from space which could have landed somewhere in Ireland.

He said they were very keen to hear from anyone who has footage of what is suspected to be a meteor falling.

"We're fairly certain that it was a rock from space, a meteor which may have dropped a meteorite," he said.

"We are asking people to send in their reports, so we can triangulate on the path and figure out did it land on Ireland?"

The last time a meteorite was seen over Ireland was in 1999 over Carlow and there was a similar event over the skies of Northern Ireland 30 years earlier.

Mr Moore said that no pictures had yet come to light of the incident, as it only lasted a few seconds.

But, he said, security cameras often captured such explosions in the sky.

"What can happen is security cameras that are filming in car parks or outdoors can catch these shooting stars, these fireballs, accidentally. So if anybody has any footage of that, we would be delighted to see it.

"We think...it came from the west across the centre of Ireland, which means everybody would have seen it. We have reports from Cork and even from up as far as Donegal."

He said security cameras in Northern Ireland facing towards the south probably would have picked it up.

Anyone who saw it is asked to contact the Astronomy Ireland website on www.astronomy.ie.

"We will publish a report there in a few days," said Mr Moore.

"We will also predict where any meteorite might have fallen, as we did with Carlow in 1999. A lady found the meteorite in a small country lane.

"They will look like melted rocks, probably not very large. We are looking for objects that would fit, in that particular case, in a mug. But they could be larger."

Ice bridge ruptures in Antarctic

Scientists say the collapse could mean the Wilkins Ice Shelf is on the brink of breaking away, and provides further evidence of rapid change in the region.

Sited on the western side of the Antarctic Peninsula, the Wilkins shelf has been retreating since the 1990s.

Researchers regarded the ice bridge as an important barrier, holding the remnant shelf structure in place.

Its removal will allow ice to move more freely between Charcot and Latady islands, into the open ocean.

The ice bridge has splintered at its thinnest point

European Space Agency satellite pictures had indicated last week that cracks were starting to appear in the bridge. Newly created icebergs were seen to be floating in the sea on the western side of the peninsula, which juts up from the continent towards South America's southern tip.

Professor David Vaughan is a glaciologist with the British Antarctic Survey who planted a GPS tracker on the ice bridge in January to monitor its movement.

He said the breaking of the bridge had been expected for some weeks and much of the ice shelf behind was likely to follow.

"We know that [the Wilkins Ice Shelf] has been completely or very stable since the 1930s and then it started to retreat in the late 1990s. But we suspect that it's been stable for a very much longer period than that," he told BBC News.

"The fact that it's retreating and now has lost connection with one of its islands is really a strong indication that the warming on the Antarctic is having an effect on yet another ice shelf."

While the break-up will have no direct impact on sea level because the ice is floating, it heightens concerns over the impact of climate change on this part of Antarctica.

Over the past 50 years, the peninsula has been one of the fastest warming places on the planet.

Many of its ice shelves have retreated in that time and six of them have collapsed completely (Prince Gustav Channel, Larsen Inlet, Larsen A, Larsen B, Wordie, Muller and the Jones Ice Shelf).

Separate research shows that when ice shelves are removed, the glaciers and landed ice behind them start to move towards the ocean more rapidly. It is this ice which can raise sea levels, but by how much is a matter of ongoing scientific debate.

Such acceleration effects were not included by the UN's Intergovernmental Panel on Climate Change (IPCC) when it made its latest projections on likely future sea level rise. Its 2007 assessment said ice dynamics were poorly understood.

Baby broccoli 'controls gut bug'

The bacteria lives in the gastrointestinal tract

The study in Cancer Prevention Research of 50 people in Japan found eating 2.5 ounces of broccoli sprouts each day for two months may confer some protection.

They contain sulforaphane, previously found to act as an antibiotic.

UK experts said while sprouts may have an effect on the bug, they were likely to make "no difference" to cancer risk.

In the study, an international team of scientists gave half the group a daily portion of broccoli sprouts and the rest alfalfa sprouts, which do not contain sulforaphane.

In those who ate broccoli sprouts, levels of a marker of H. pylori in human stools called HpSA was cut by over 40%.

There was no HpSA level change in those who ate alfalfa sprouts.

In people who ate broccoli sprouts, HpSA levels had returned to pre-treatment levels eight weeks after people stopped eating them.

The researchers say this suggests that although the sprouts can dampen down H. pylori, they do not eradicate it.

Sprout smoothies

Dr Jed Fahey, of Johns Hopkins University in the US who led the study, said: "The fact that the levels of infection and inflammation were reduced suggests the likelihood of getting gastritis and ulcers and cancer is probably reduced."

It was Dr Fahey who discovered the sprouts contained sulforaphane early this decade. He is a co-founder of a company licensed by The Johns Hopkins University to produce broccoli sprouts. A portion of the proceeds is used to help support cancer research.

His team also carried out tests on mice infected with H. pylori, giving them broccoli-sprout smoothies for eight weeks.

The number of H. pylori bacteria in the mice's stomachs fell significantly - but did not change in infected mice that only drank plain water.

A second group of H. pylori-infected mice were genetically engineered to lack the Nrf2 gene that activates protective enzymes.

They failed to respond in the same way to the sprout-smoothie diet.

Nell Barrie of Cancer Research UK said: "This small study shows that eating broccoli sprouts might reduce levels of H. pylori infection.

"We know that H. pylori is a major risk factor for stomach cancer but only three in a 100 people with the infection will develop the disease, so there are clearly other factors at work.

"This means we can't conclude that eating broccoli sprouts makes any real difference to the chance of getting stomach cancer. "

Setback for climate technical fix

By Richard Black Environment correspondent, BBC News website

The experiment may have been compromised by voracious amphipods

The biggest ever investigation into "ocean fertilisation" as a climate change fix has brought modest results.

The idea is that putting iron filings in the ocean will stimulate growth of algae, which will absorb CO2 from air.

But scientists on the Lohafex project, which put six tonnes of iron into the Southern Ocean, said little extra carbon dioxide was taken up.

The German environment ministry and campaign groups had tried to stop the project which they called "dangerous".

Leaders of the German-Indian expedition said they had gained valuable scientific information, but that their results suggested iron fertilisation could not have a major impact, at least in that region of the oceans.

"There's been hope that one could remove some of the excess carbon dioxide - put it back where it came from, in a sense, because the petroleum we're burning was originally made by the algae," said Victor Smetacek from the Alfred Wegener Institute in Bremerhaven.

"But our results show this is going to be a small amount, almost negligible."

Food chain

Previous experiments, which have been going on for at least a decade, had indicated that iron particles could stimulate the growth of phytoplankton - algae - and that when the phytoplankton died, they fell to the sea floor, meaning that carbon taken from the air was effectively locked away on the bottom of the ocean.

Following fertilisation of a 300 sq km patch of ocean, Lohafex, too, saw a burst of algal growth.

But within two weeks, the algae were being eaten by tiny creatures called copepods, which were then in turn eaten by amphipods, a larger type of crustacean.

The net result was that far less carbon dioxide was absorbed and sent to the sea floor than scientists had anticipated.

"What it means is the Southern Ocean cannot sequester the amount of carbon dioxide that one had hoped," concluded Professor Smetacek.

Satellites can spot phytoplankton blooms in the process of formation

One key issue appears to be the type of algae that grows in response to the extra iron.

Earlier experiments had found diatoms blooming - organisms with a protective silicate casing.

But in the Lohafex area, the diatom population could not increase because the waters were depleted of silicon.

Some scientists have long argued that the iron fertilisation vision was flawed because lack of iron was not always the factor limiting growth; and this result appears to back that contention.

Growing concerns

The Lohafex expedition, which used the German Polarstern ship, was controversial from the outset, with Greenpeace leading demands that it be stopped.

The campaign group said tipping iron filings into the sea amounted to pollution, and was forbidden under international agreements including the UN Convention on Biological Diversity, which at its 2008 meeting had called for a de facto moratorium on such experiments except at small scale in coastal waters.

"There are two things that concern us," said Greenpeace scientist David Santillo.

"Firstly, there's the direct impacts from the experiments themselves, and as the scale of the experiments has gone up and up there's much greater potential for those direct results," he told BBC News.

"But a second and broader concern is that if we're going to be pursuing this as a climate mitigation strategy, then we're looking at a state of the world where we rely on manipulating the ocean on a truly huge scale and that would undoubtedly have large and possibly irreversible effects on ocean ecosystems."

The German government put the expedition on hold earlier this year because of these concerns, but subsequently allowed it to proceed.

A commercial company, Climos, is planning a much larger experiment that could cover up to 40,000 sq km of ocean.

It hopes eventually to receive funding through the global carbon market if it can demonstrate that the technique can sequester large quantities of the greenhouse gas.

Cold fusion debate heats up again

Pons and Fleischmann's announcement of cold fusion came on 23 March 1989

Cold fusion, first announced 20 years ago on Monday, was claimed to be a boundless source of clean energy by Martin Fleischmann and Stanley Pons.

Attempts to replicate their experiments failed, but a number of researchers insist that cold fusion is possible.

The meeting will see several approaches that claim to produce fusion power.

The American Chemical Society has organised sessions surrounding the research at its meetings before, suggesting that the field would otherwise have no suitable forum for debate.

In a bid to avoid the negative connotations of a largely discredited approach, research in the field now appears under the umbrella of "low-energy nuclear reactions", or LENR.

Gopal Coimbatore, ACS program chair for an LENR session at the 2007 national meeting, said that "with the world facing an energy crisis, it is worth exploring all possibilities".

Heating up

The principle of cold fusion runs counter to that of other fusion production mechanisms that employ enormous lasers or magnetic chambers to contain searingly hot gas.

Pons and Fleischmann ran a current through a simple, room-temperature device called an electrolytic cell.

They observed a heat rise in the cell, suggesting that power was being produced within it from nuclear fusion.

However, a flurry of attempts to repeat the experiment around the world, an extensive review by the US Department of Energy of cold fusion research, and a few years spent by Pons and Fleischmann themselves working on the approach in France failed to establish cold fusion as a reality.

Researchers who pursue LENR approaches say that their work has been marginalised and suffers from a chronic lack of funding in the wake of the initial, flawed announcement.

Frank Close, a professor of theoretical physics at the University of Oxford, says that the far greater problem with cold fusion claims is that results from any given study have never been independently verified - a problem that plagued that first announcement.

"Nothing's really changed in 20 years. I'm not at all surprised that something is being said today," Professor Close told BBC News.

"It is an interesting date in the calendar of wrong results that claim to be science."

NIF, the world's largest laser, is designed to initiate nuclear fusion

Many of the details of Pons' and Fleischmann's original electrolytic cell feature in more recent work, including the type of metal used in the cell's electrodes and water made from a heavy isotope of hydrogen.

One wholly new approach will be explained by researchers from Hokkaido University, who have seen unexplained heat production in a chamber filled with compressed hydrogen and a chemical called phenanthrene.

Professor Close said that many inexplicable phenomena have arisen in the 20 years since Pons' and Fleischmann's announcement that have been tagged with the "cold fusion" moniker.

"If I come up with a weird phenomenon and call it cold fusion, I know that reporters will be interested. Convincing the scientific community is another matter entirely."

Synthetic blood from embryos bid

Blood supplies are stretched

UK scientists plan a major research project to see if synthetic human blood can be made from embryonic stem cells.

Led by the Scottish National Blood Transfusion Service, the three year trial could provide an unlimited supply of blood for emergency transfusions.

The blood should be free of infections like the human form of mad cow disease.

Teams will test human embryos left over from IVF treatment to find those destined to develop into the universal "O-negative" blood donor group.

O-negative blood can be transfused into anyone without fear of tissue rejection and is the only safe option when a patient's blood group is unknown or not immediately available.

This precious blood is in limited supply because only 7% of the population belongs to this blood group.

The Wellcome Trust is understood to have promised £3 million towards the cost of the multimillion-pound project, with further funding coming from the blood transfusion services of Scotland, and England and Wales.

The Irish government is also believed to be involved.

The project will be led by Professor Marc Turner of Edinburgh University who is the director of the Scottish National Blood Transfusion Service.

He said the work would begin in the next few weeks after final approval had been gained from the relevant research bodies.

Making fake blood from embryos 1. Embryo created from IVF is tested for O-negative blood group, then allowed to develop for several days until stem cells can be extracted 2. Stem cells are cultured in laboratory with nutrients to stimulate red blood cell creation 3. Nuclei are removed in final stage to produce oxygen-carrying mature blood cells. Trillions of these will be needed to build up a blood bank

Stem cells are the body's master cells, with the ability to transform into any type of tissue.

Scientists have already shown it is possible to take a single stem cell from an early human embryo and encourage it to develop into mature blood cells in the laboratory.

And a US firm called Advanced Cell Technology has managed to produce billions of red blood cells from embryonic blood cells in this way.

The challenge now is to scale up the production and move the science from the lab to the bedside, which will take years.

Professor Turner said: "We should have proof of principle in the next few years, but a realistic treatment is probably five to 10 years away.

"In principle, we could provide an unlimited supply of blood in this way."

However, many groups object to the use of embryonic stem cells on the grounds that it is unethical to destroy embryos in the name of science.

Josephine Quintavalle of the public interest group Comment on Reproductive Ethics said: "Like so many of the claims associated with embryonic stem cells, this is first steps research rather than a cure around the corner, and just as hypothetical as the rest of the claims which try to justify destroying the human embryo for the benefit of mankind.

"Associating this controversial research with a National Blood Transfusion service may even end up contaminating the feel-good image of blood banks.

"Those who donate blood but who defend the right to life of the human embryo may be reluctant to continue giving their blood."

Battery that 'charges in seconds'

The material is cheap, and batteries made with it are less likely to explode

A new manufacturing method for lithium-ion batteries could lead to smaller, lighter batteries that can be charged in just seconds.

Batteries that discharge just as quickly would be useful for electric and hybrid cars, where a quick jolt of charge is needed for acceleration.

The approach only requires simple changes to the production process of a well-known material.

The new research is reported in the scientific journal Nature.

Because of the electronic punch that they pack, gram for gram, lithium-ion batteries are the most common rechargeable batteries found in consumer electronics, such as laptops.

However, they take a long time to charge; researchers have assumed until now that there was a speed limit on the lithium ions and electrons that pass through the batteries to form an electrochemical circuit.

Tiny holes

Gerbrand Ceder, at the Massachusetts Institute of Technology (MIT), US, and his colleagues used a computer simulation to model the movements of ions and electrons in a variant of the standard lithium material known as lithium iron phosphate.

The simulation indicated that ions were moving at great speed.

"If transport of the lithium ions was so fast, something else had to be the problem," Professor Ceder said.

That problem turned out to be the way ions passed through the material.

They pass through minuscule tunnels, whose entrances are present at the surface of the material.

However, the team discovered that to get into these channels, the ions had to be positioned directly in front of the tunnel entrances - if they were not, they could not get through.

The solution, Ceder discovered, was to engineer the material such that it has a so-called "beltway" that guides the ions towards the tunnel entrances.

Traffic management

A prototype battery made using the new technique could be charged in less than 20 seconds - in comparison to six minutes with an untreated sample of the material.

Most commercial batteries use a material made up of lithium and cobalt, but lithium iron phosphate does not suffer from overheating - something that has affected laptop and mp3 player batteries in a number of incidents.

Hybrid cars could benefit from a quick discharge as much as a quick charge

Even though it is cheap, lithium iron phosphate has until now received little attention because lithium cobalt batteries can store slightly more charge for a given weight.

However, the researchers found that their new material does not lose its capacity to charge over time in the way that standard lithium ion batteries do.

That means that the excess material put into standard batteries to compensate for this loss over time is not necessary, leading to smaller, lighter batteries with phenomenal charging rates.

What is more, because there are relatively few changes to the standard manufacturing process, Professor Ceder believes the new battery material could make it to market within two to three years.

Nasa space shuttle launch delayed

The leak was spotted as fuel tanks were being filled

Nasa has delayed the launch of its Discovery shuttle mission to complete the electricity generation system on the International Space Station (ISS).

A fuel leak meant Wednesday's launch would be delayed until Sunday at the earliest, the US space agency said.

The orbiter is due to deliver the fourth and final set of solar array wings to the platform and the last segment of its truss, or backbone.

Their electricity will support the expansion of the crew to six people.

The 73m-long arrays will also provide the power necessary to fully exploit the science labs now attached to the ISS.

Currently, the normal live-aboard complement is three individuals; and the station partners want to double this in May.

Discovery had been due to lift off from the Kennedy Space Center in Florida on Wednesday evening.

But in a statement Nasa said lift-off was now scheduled for Sunday evening, though the "exact launch date is dependent on the work necessary to repair the problem".

A progress assessment would be made on Thursday, Nasa said.

'Waiting'

The 14-day mission is due to feature four spacewalks to help install the S6 truss segment to the starboard, or right, side of the station and the deployment of its solar arrays.

Discovery's astronauts will also replace a failed unit for a system that converts urine to drinking water.

Another key task is ISS crew rotation. Discovery will drop off the Japanese space agency's (Jaxa) first resident crew member.

Dr Koichi Wakata is an experienced astronaut, having flown on two previous shuttle missions. He is expected to stay on the ISS until June.

"This week will be an historic week for Japan's space programme," said Kuniaki Shiraki, executive director of Jaxa's human space programme.

"We have been waiting a long time."

Dr Wakata takes the place of Nasa astronaut Sandra Magnus, who has served as a flight engineer on the platform since November.

Last missions

Discovery's delayed flight would be the 125th to be made by a shuttle; the 28th to the ISS; and the 36th flight for Discovery itself.

Once the final truss segment is installed, the station's backbone - which supports not just the arrays, but radiators and other equipment - will be 102m long.

When viewed from the Earth's surface shortly after sunset, the ISS appears as a very bright star moving swiftly across the sky. The addition of a larger reflective area will make the platform an even more brilliant spectacle.

Altogether, the station's arrays can generate as much as 120 kilowatts of usable electricity, says Nasa.

The addition of the final set of solar arrays will nearly double the amount of power available for scientific experiments aboard the station - from 15kW to 30kW.

Eight more flights are required to finish construction of the station and to fill it with supplies prior to the retirement of the shuttle fleet in 2010.

Nasa also plans one additional shuttle mission to repair and upgrade the Hubble Space Telescope.

The agency is still awaiting the appointment of an administrator following the departure of the Mike Griffin. President Obama has yet to fill the post.

Discovery's mission had earlier been delayed by several weeks to give engineers time to investigate the cause of a fractured fuel valve on the last shuttle mission.

Light 'could detect Parkinson's'

The Keele University team told a conference that a "super-microscope" could spot changes in brain cells before the disease destroyed them.

Keele's Dr Joanna Collingwood said that the technique was "pioneering".

She told the American Association for the Advancement of Science patients could be treated sooner as a result.

'Early diagnosis'

Dr Collingwood said the team had been using a synchrotron - or Diamond Light Source (DLS) - at Harwell, Oxfordshire.

The device is a large doughnut-shaped particle accelerator, the size of five football pitches, which fires particles at just below the speed of light, focusing them into a beam less than a single cell in diameter.

It allows researchers to to observe iron levels in individual brain cells, which are affected by Parkinson's.

Dr Collingwood told the AAAS conference in Chicago: "We have been able to investigate human tissue with such precision that metal ions, particularly iron levels, in and around individual cells can be mapped.

"The technique is pioneering in that it does not change the distribution or form of the metals in the tissue being studied."

She said she hoped that the team's work could help doctors detect early signs of Parkinson's using MRI.

"Early diagnosis is key because we know that by the time a typical individual presents with the symptoms of the disease, chemical changes have already caused significant cell death of vulnerable motor neurones," she added.

Bleak forecast on fishery stocks

Some Atlantic cod fisheries could drop by 50% by 2050

Changing ocean temperatures and currents will force thousands of species to migrate polewards, including cod, herring, plaice and prawns.

By 2050, US fishermen may see a 50% reduction in Atlantic cod populations.

The predictions of "huge changes", published in the journal Fish and Fisheries, were presented at the AAAS annual meeting in Chicago.

Marine biologists used computer models to forecast the future of 1,066 commercially important species from across the globe.

"The impact of climate change on marine biodiversity and fisheries is going to be huge," said lead author Dr William Cheung, of the University of East Anglia in the UK.

"We must act now to adapt our fisheries management and conservation policies to minimise harm to marine life and to our society.

"We can use our knowledge to improve the design of marine protected areas which are adaptable to changes in distribution of the species," he told the conference.

Sinking feeling

The world's oceans are already experiencing changes in temperature and current patterns are changing due to climate change.

Existing patterns of catches will change

To quantify the likely impact on sea life, Dr Cheung and his team developed a new computer model that predicts what might happen under different climate scenarios.

While scientists have made projections of climate change impact on land species, this is the most comprehensive study on marine species ever published.

"We found that on average, the animals may shift their distribution towards the poles by 40km per decade," said Dr Cheung.

"Atlantic cod on the east coast of the US may see a 50% reduction in some populations by 2050."

The invasion of new species into unfamiliar environments could seriously disrupt ecosystems, the researchers warn.

Some species will face a high risk of extinction, including Striped Rock Cod in the Antarctic and St Paul Rock Lobster in the Southern Ocean.

Sea-saw

But of course, as fish migrate polewards, fishermen in some areas will see their stocks increase.

The model predicts an increased catch in the North Sea - benefiting fishermen from Nordic countries.

But fishermen in tropical developing countries will suffer major losses in catch.

The socio-economic impact could be devastating, according to another study published recently in the same journal.

Thirty-three nations in Africa, Asia and South America are highly vulnerable to the impact of climate change in fisheries, according to scientists from the World Fish Centre.

Of these, 19 were already classified by the United Nations as "least developed" because of their particularly poor socioenomic conditions.

"Economically, people in the tropics and subtropics likely will suffer most, because fish are so important in their diets and because they have limited capacity to develop other sources of income and food," said Edward Allison, director of policy, economics and social science at WorldFish.

"We believe it is urgent to start identifying these vulnerable countries, because the damage will be greatly compounded unless national governments and international institutions like the World Bank act now to include the fish sector in plans for helping the poor cope with climate change."

Emperor penguins face extinction

Less ice could spell bad news for a great many species

Emperor penguins, whose long treks across Antarctic ice to mate have been immortalised by Hollywood, are heading towards extinction, scientists say.

Based on predictions of sea ice extent from climate change models, the penguins are likely to see their numbers plummet by 95% by 2100.

That corresponds to a decline to just 600 breeding pairs in the world.

The research is published in the journal Proceedings of the National Academy of Sciences.

Emperor penguins, the largest species, are unique in that they are the only penguins that breed during the harsh Antarctic winters.

Colonies gather far inland after long treks across sea ice, where the females lay just one egg that is tended by the male. That means that the ice plays a major role in their overall breeding success.

What is more, the extent of sea ice cover influences the abundance of krill and the fish species that eat them - both food sources for the penguins.

Hal Caswell of the Woods Hole Oceanographic Institute and his colleagues used projections of sea ice coverage from the Intergovernmental Panel on Climate Change's (IPCC) last report.

In addition, they used a "population dynamics" model describing the mating patterns and breeding success of emperor penguins.

The model has been honed using 43 years' worth of observations of an emperor colony in Antarctica's Terre Adelie.

Slow learners

While there are a number of models and scenarios in the IPCC report, the team used only 10 of them - those that fit with existing satellite data on sea ice.

They then ran 1,000 simulations of penguin population growth or decline under each of those 10 climate scenarios.

The results suggest that by the year 2100, emperor penguins in the region are likely to experience a reduction in their numbers by 95% or more.

The likelihood of this occurring, according to the researchers, is at least a one-in-three chance and possibly more than eight out of 10.

Though the penguins could avert disaster by shifting their breeding patterns with the climate, the study's lead author Stephanie Jenouvrier said that was unlikely.

"Unlike some other Antarctic bird species that have altered their life cycles, penguins don't catch on so quickly," she said.

"They are long-lived organisms, so they adapt slowly. This is a problem because the climate is changing very fast."

'Conservative approach'

Several prior studies have shown that climate change can affect the reproduction and geographic distribution of species, but this is the first that makes predictions about the ultimate fate of a species as a whole.

"I don't see any reason not to take these predictions very seriously," said Dan Reuman, a population biologist at Imperial College London.

Particularly warm seasons cause Antarctic ice to break up early

"The study is based on a wide range of climate forecasts, it takes a conservative approach, it's based on a large amount of data on penguin demography, and the model accurately forecasts the data that already exist."

Dr Reuman suggests that more of this kind of work should be done to understand the species-by-species effects of climate change, and thereby the influence on whole communities.

It is an idea echoed by Joel Cohen, head of the Laboratory of Populations at Rockefeller University.

"The emperor penguin is an important species in its own right, but the whole communities in which it's embedded are also of importance," he told BBC News.

The penguins also serve as a species that particularly draws attention to the crisis in their region, he added.

"They are to Antarctica what the polar bear is to the Arctic.

"This study takes our knowledge, puts it together, gives us some insights, arouses concern and suggests that we ought to be understanding this situation a lot better."

Government touts science for all

The campaign includes adverts showing the science in everyday life

The government has launched a campaign to reduce public perception of science as "elitist".

The Science [So What? So Everything] campaign is being run by the Department for Innovation, Universities and Skills (Dius).

The effort follows the publication of a survey that shows most people feel that science is remote, elitist and irrelevant to their lives.

The launch event will include a celebrity debate and evening expo.

The round-table debate will open the launch at Downing Street, and Cabinet ministers are expected to be joined by a long list of high-profile figures to find better ways of public engagement in science.

Those expected to attend include David Attenborough, chef Hugh Fearnley-Wittingstall and writer Bill Bryson.

'Geeky image'

According to the Science Minister, Lord Drayson, changing public attitudes to science will be important to the UK economy.

"Continued success in science and technology is vital to our future - and yet there is still a perception among many of our people that science is too clever for them or elitist in some way," he said.

A recent poll by Dius showed a marked disconnect in people's faith in science and its relevance to their lives.

Of those polled, 48% said they expected science to find a cure for cancer within 30 years. But only 3% said that scientists were the group of people that had the most effect on their lives.

The campaign was welcomed by Diana Garnham, Chief Executive of the Science Council.

"It's great to see the concept of everyday science come to the fore," she said.

"We need to get away from the elitist, geeky image that science suffers from.

"We're not going to get more young people getting into science because we tell them that their country needs them, and research shows that they aren't persuaded by arguments that they will earn more if they get into science."

However, environmental commentator George Monbiot said that the publicly funded campaign should not be a propaganda vehicle for vested interests.

"When Tony Blair said people who were against GM technology were anti-science, he was confusing a technology with people's attitudes toward science," he said.

"The conflation of improving country's scientific literacy with the promoting industrial interests of a particular group is dishonest and I hope this won't happen with this campaign."

Emperor penguins face extinction

Less ice could spell bad news for a great many species

Emperor penguins, whose long treks across Antarctic ice to mate have been immortalised by Hollywood, are heading towards extinction, scientists say.

Based on predictions of sea ice extent from climate change models, the penguins are likely to see their numbers plummet by 95% by 2100.

That corresponds to a decline to just 600 breeding pairs in the world.

The research is published in the journal Proceedings of the National Academy of Sciences.

Emperor penguins, the largest species, are unique in that they are the only penguins that breed during the harsh Antarctic winters.

Colonies gather far inland after long treks across sea ice, where the females lay just one egg that is tended by the male. That means that the ice plays a major role in their overall breeding success.

What is more, the extent of sea ice cover influences the abundance of krill and the fish species that eat them - both food sources for the penguins.

Hal Caswell of the Woods Hole Oceanographic Institute and his colleagues used projections of sea ice coverage from the Intergovernmental Panel on Climate Change's (IPCC) last report.

In addition, they used a "population dynamics" model describing the mating patterns and breeding success of emperor penguins.

The model has been honed using 43 years' worth of observations of an emperor colony in Antarctica's Terre Adelie.

Slow learners

While there are a number of models and scenarios in the IPCC report, the team used only 10 of them - those that fit with existing satellite data on sea ice.

They then ran 1,000 simulations of penguin population growth or decline under each of those 10 climate scenarios.

The results suggest that by the year 2100, emperor penguins in the region are likely to experience a reduction in their numbers by 95% or more.

The likelihood of this occurring, according to the researchers, is at least a one-in-three chance and possibly more than eight out of 10.

Though the penguins could avert disaster by shifting their breeding patterns with the climate, the study's lead author Stephanie Jenouvrier said that was unlikely.

"Unlike some other Antarctic bird species that have altered their life cycles, penguins don't catch on so quickly," she said.

"They are long-lived organisms, so they adapt slowly. This is a problem because the climate is changing very fast."

'Conservative approach'

Several prior studies have shown that climate change can affect the reproduction and geographic distribution of species, but this is the first that makes predictions about the ultimate fate of a species as a whole.

"I don't see any reason not to take these predictions very seriously," said Dan Reuman, a population biologist at Imperial College London.

Particularly warm seasons cause Antarctic ice to break up early

"The study is based on a wide range of climate forecasts, it takes a conservative approach, it's based on a large amount of data on penguin demography, and the model accurately forecasts the data that already exist."

Dr Reuman suggests that more of this kind of work should be done to understand the species-by-species effects of climate change, and thereby the influence on whole communities.

It is an idea echoed by Joel Cohen, head of the Laboratory of Populations at Rockefeller University.

"The emperor penguin is an important species in its own right, but the whole communities in which it's embedded are also of importance," he told BBC News.

The penguins also serve as a species that particularly draws attention to the crisis in their region, he added.

"They are to Antarctica what the polar bear is to the Arctic.

"This study takes our knowledge, puts it together, gives us some insights, arouses concern and suggests that we ought to be understanding this situation a lot better."

Coral reef growth is slowest ever

Porites and other corals provide habitat for thousands of species

Coral growth in Australia's Great Barrier Reef has slowed to its most sluggish rate in the past 400 years.

The decline endangers the species the reef supports, say researchers from the Australian Institute of Marine Science.

They studied massive porites corals, which are several hundred years old, and found that calcification has declined by 13.3% since 1990.

Global warming and the increasing acidity of seawater are to blame, they write in Science journal.

Coral reefs are central to the formation and function of ecosystems and food webs for tens of thousands of other marine organisms.

The Great Barrier Reef is the largest in the world, composed of over 2,900 individual reefs and 900 islands.

Dr Glenn De'ath and colleagues investigated 328 colonies of massive Porites corals, from 69 locations.

The largest corals are centuries old - growing at a rate of just 1.5cm per year.

By looking at the coral skeletons, they determined that calcification - or the deposit of calcium carbonate - has declined by 13.3% throughout the Great Barrier Reef since 1990.

Such a decline is unprecedented in at least the past 400 years, they write.

The researchers warn that changes in biodiversity are imminent, both at the Great Barrier Reef and at other reef systems throughout the world's oceans.

Growing at 1.5 cm/year, large Porites corals are hundreds of years old

Mars rovers roll on to five years

The rovers keep on rolling across the dusty surface

The US space agency's (Nasa) Mars rovers are celebrating a remarkable five years on the Red Planet.

The first robot, named Spirit, landed on 3 January, 2004, followed by its twin, Opportunity, 21 days later.

It was hoped the robots would work for at least three months; but their longevity in the freezing Martian conditions has surprised everyone.

The rovers' data has revealed much about the history of water at Mars' equator billions of years ago.

"These rovers are incredibly resilient considering the extreme environment the hardware experiences every day," said John Callas, project manager for Spirit and Opportunity at Nasa's Jet Propulsion laboratory in Pasadena, California.

"We realise that a major rover component on either vehicle could fail at any time and end a mission with no advance notice, but on the other hand, we could accomplish the equivalent duration of four more prime missions on each rover in the year ahead."

Spirit is exploring a 150km-wide bowl-shaped depression known as Gusev Crater. It has found an abundance of rocks and soils bearing evidence of extensive exposure to water.

Opportunity is on the other side of the planet, in a flat region known as Meridiani Planum.

Some of the rocks seen by Opportunity were once "drenched" in water

Its data has shown conclusively that Mars sustained liquid water on its surface. The sedimentary rocks at its study location were laid down under gently flowing surface water.

The rovers are now showing some serious signs of wear and tear.

Spirit has to drive backwards everywhere it goes because of a jammed wheel; and Opportunity's robotic arm has a glitch in a shoulder joint because of a broken electrical wire.

There have been times also when the vehicles' have been dangerously short on power because of the dust covering on their solar panels.

The vehicles continue to return breathtaking panoramas

When Spirit and Opportunity do eventually fail, Nasa will have to wait awhile for its next surface mission.

It recently delayed this year's planned launch to 2011 of a much more capable vehicle, known as the Mars Science Laboratory (MSL). The rover project has been beset by technical and budgetary problems.

The decision was taken not long after Europe also put back its rover venture known as ExoMars. Officials cited cost concerns.

It is likely all surface missions in future for Nasa and the European Space Agency will be joint affairs because of the high cost of getting spacecraft down on to the planet.

Nasa lost contact with its static Phoenix lander in November. It was operating in much more difficult conditions at a high-latitude location.

The rovers succeeded where some other missions failed