'Fossil' fireballs from supernovae discovered by Suzaku observatory

Studies of two supernova remnants using the Japan-US Suzaku observatory have revealed never-before-seen embers of the high-temperature fireballs that immediately followed the explosions. Even after thousands of years, gas within these stellar wrecks retain the imprint of temperatures 10,000 times hotter than the sun's surface.
Source: ScienceDaily: Latest Science News | 11 Jan 2010 | 12:00 pm

New method of measuring ocean carbon dioxide uptake could lead to climate change 'early warning system'

Scientists have developed a new method of measuring the absorption of carbon dioxide by the oceans and mapped for the first time carbon dioxide uptake for the entire North Atlantic.
Source: ScienceDaily: Latest Science News | 11 Jan 2010 | 12:00 pm

How to divide and conquer 'social network' of cells

On Noah's Ark animals came in twos: male and female. In human bodies trillions of cells are coupled, too, and so are the molecules from which they are composed. Yet these don't come in twos, they are regrouped into indistinguishable clusters. Because these complex cell networks are the backbone of life -- and illness -- scientists have long searched for ways to splice cell clusters down to their original pairs.
Source: ScienceDaily: Latest Science News | 11 Jan 2010 | 12:00 pm

Brain activity levels affect self-perception: 'Rose-colored glasses' correlate with less frontal lobe use

The less you use your brain's frontal lobes, the more you see yourself through rose-colored glasses, researchers have found.
Source: ScienceDaily: Latest Science News | 11 Jan 2010 | 12:00 pm

More evidence that autism is a brain 'connectivity' disorder

Studying a rare disorder that also causes autism in 25-50 percent of affected patients, new research supports the emerging idea that autism results from disrupted brain "connectivity" causing improper information flow. These abnormalities might be reversible with rapamycin or rapamycin-like drugs, which the studies researchers will be bringing to clinical trial later this year.
Source: ScienceDaily: Latest Science News | 11 Jan 2010 | 12:00 pm

Nanoscience goes 'big': Discovery could lead to enhanced electronics

Nanoscience has the potential to play an enormous role in enhancing a range of products, including sensors, photovoltaics and consumer electronics. Scientists in this field have created a multitude of nano scale materials, such as metal nanocrystals, carbon nanotubes and semiconducting nanowires.
Source: ScienceDaily: Latest Science News | 11 Jan 2010 | 12:00 pm

Predicting survival for pulmonary arterial hypertension patients

Setting out to determine the survival of patients with pulmonary arterial hypertension (PAH), researchers have discovered that an equation used for more than 20 years to predict survival is outdated. Accordingly, they developed a new survival prediction equation that will impact clinical practice and the drug development process.
Source: ScienceDaily: Latest Science News | 11 Jan 2010 | 9:00 am

Paper strips can quickly detect toxin in drinking water

A strip of paper infused with carbon nanotubes can quickly and inexpensively detect a toxin produced by algae in drinking water.
Source: ScienceDaily: Latest Science News | 11 Jan 2010 | 9:00 am

Bering Strait influenced ice age climate patterns worldwide

In a vivid example of how a small geographic feature can have far-reaching impacts on climate, new research shows that water levels in the Bering Strait helped drive global climate patterns during ice age episodes dating back more than 100,000 years.
Source: ScienceDaily: Latest Science News | 11 Jan 2010 | 9:00 am

Camera traps yield first-time film of tigress and cubs

Camera traps deep in the Sumatran jungle have captured first-time images of a rare female tiger and her cubs, giving researchers unique insight into the elusive tiger's behavior. Specially designed video cameras installed by WWF-Indonesia's researchers caught the mother tiger and her cubs on film as they stopped to sniff and check out the camera trap.
Source: ScienceDaily: Latest Science News | 11 Jan 2010 | 9:00 am

Prayer and nonsense | Andrew Brown

The patent untruth of religious language might have more benefits besides making it memorable

I have been reading the letters of CS Lewis again: they seem written from an immense distance. In important ways, they are. He reached the trenches, as a second lieutenant in France, on his 19th birthday; of the time when he got his blighty wound, the regimental history records that

The casualties of the 1st battalion between 14th and 16th April were: 2/Lieut. L.B. Johnson died of wounds (15/4/18) and 2/Lieuts C.S. Lewis, A.G. Rawlence, J.R. Hill and C.S. Dowding wounded: in other ranks the estimated losses were 210 killed, wounded and missing.

Incidentally, the wounds that ended his war were caused by a British shell dropping short, or what we would now call "friendly fire". But when there are 215 casualties in one unexceptional regiment within two days, no one makes a big fuss about whose shells kill whom.

But for all the social distance to Lewis's world, two of his characteristics leap straight to ours. The first is what a good reader he was, which is to say a good critic. The other is that it mattered. He was always trying to write something more than "a readable and convincing slab of claptrap" (as he described Macauley) and very seldom failed, however often he was wrong.

But his mythology of language was extremely strange. In a letter to his brother, (17 January 1932) he writes

As we learn to talk we forget what we have to say. Humanity, from this point of view, is rather like a man coming gradually awake and trying to describe his dreams: as soon as his mind is sufficiently awake for a clear description, the thing which was to be described is gone … Religion and poetry are about the only languages in modern Europe – if you can regard them as "languages" – which till have traces of the dream in them, still have something to say. Compare "Our Father which art in Heaven" with "The supreme being transcends space and time". The first goes to pieces if you begin to apply literal meaning to it. How can anything but a sexual animal really be a father? How can it be in the sky? The second falls into no such traps. On the other hand the first really means something, really represents a concrete experience in the minds of those who use it: the second is mere dextrous playing with counters, and once a man has learned the rule he can go on that way for two volumes without really using the words to refer to any concrete fact at all ...

I am not interested here in the question of whether there is any external referent for "Our Father, who art in Heaven", though I suppose I should point out for the benefit of the sky-pixie crowd that Lewis takes for granted that the meaning cannot be literal. That is the whole point of his argument.

I am more interested in a a potentially much more destructive approach, which came out of a paper published last year with the wonderful title "Connections from Kafka" by two psychologists, Travis Proulx, and Steven Heine. The very short form of their argument (which deserves a longer post on its own) is that nonsense or the violation of expectations actually strengthens our ability to find meaning. What's more, if we are exposed to nonsense or loss of meaning in one area , this will increase the meaning and order we find in others. Earlier work of theirs has shown that moral beliefs or group affiliation can be strengthened simply by swapping the experimenter out, without explanation, halfway through a test. That, surely, is the mechanism behind all modern fundamentalisms.

Anyway, there is lots of evidence that anxiety increases our tendency to see patterns and meaning in the world. The standard atheist assumption is of course that these patterns don't really exist. In some cases, and some experiments, they don't. But the latest Proulx and Heine paper had a fascinating twist: after being exposed to a twisted version of a Kafka story, in which nothing at all made sense, their subjects were better able to detect patterns that really existed in letter strings they were given to match.

The counter-intuitive nature of religious language is often remarked. There are whole theories about just how much counter-intuitiveness is needed to make a religious story most memorable and thus most widespread. But counter-intuitiveness is really just another term for the violation of expectation and the denial of meaning. If Proulx and Heine are right, then counter-intuitive religious language will not just be more memorable: it will help the participants to perceive meaning in the threatening world around them. Sometimes that meaning will be objectively there.

This is a long way back to CS Lewis, but I think it shows his instinct was right: "Our Father, who art in heaven" actually means something to the people who say it, in a way that more literally sensible language just couldn't. The rule for religious language is clear: if a dalek could understand it, it wouldn't be worth saying.

Source: Science news, comment and analysis | guardian.co.uk | 11 Jan 2010 | 3:30 am

The nation's weather (AP)

AP - Snowy conditions were expected to return to the Northeast on Monday as light and scattered mixed precipitation persisted in the Northwest.

Source: Yahoo! News: Science News | 11 Jan 2010 | 2:55 am

Biodiversity is not just about saving exotic species from extinction

Neglect of the natural services provided by biodiversity is an economic catastrophe greater than the global economic crisis

Starting Monday, celebrations and events across the world will highlight the beginning of the UN's Year of International Biodiversity and the loss of our richly varied flaura and fauna, which is estimated to be as high as 1,000 times the natural rate as a result of human activities.

Ahmed Djoghlaf, the general secretary of the treaty signed by 192 countries since 1992 to protect biodiversity, is blunt about efforts to preserve the health of biodiversity since the Rio Earth summit 18 years ago. Governments worldwide have failed to meet the treaty's target of reversing the trend for declining biodiversity, he says, and urgently need momentum to hit its targets for 2020.

Biodiversity is integral to our daily lives. It is not about the loss of exotic species which have been the focus of conservation activities by the foundations and trusts of wealthy nations. It is about the vital resources which underpin the wealth and health of the world's poor and that provide the vital needs for the heath and wellbeing of us all.

The equivalent to the Stern report for biodiversity is called The Economics of Ecosystems and Biodiversity (TEEB). It warns that our neglect of the natural services provided by biodiversity is an economic catastrophe of an order of magnitude greater than the global economic crisis. Year on year, the irreversible loss of natural diverse genetic resources impoverishes the world and undermines our ability to develop new crops and medicines, resist pests and diseases, and maintain the host of natural products on which humans rely.

Equally significant, are the vital natural services that the world's ecosystems provide. These include providing vital oxygen, decomposing waste, removing pollutants, providing the natural buffers that help manage drought and flood, protect soil from erosion, ensure soil fertility, and provide breeding nurseries to maintain fish ocean stocks. The list goes on, and among these immeasurable vital functions of nature is of course its ability to absorb carbon dioxide. The ability of forests, bogs and salt marches, tundra, coral and ocean plankton to sequester carbon should be our greatest ally in managing the increased emissions of fossil fuel activity – a key theme of the climate negotiations in Copenhagen last month.

Rather than seeing biodiversity and ecological mechanisms being eroded, we need to see a massive effort towards finding a more effective sustainable relationship between human society and nature. This is not a scientific or environmental issue, it is a social question and an ethical one about what our generation leaves for those in the future.

• Dr Robert Bloomfield is the coordinator for the UK International year of biodiversity, which features talks, exhibitions, public dialogues, art work and citizen science experiments encompassing both science and the arts.

Source: Science news, comment and analysis | guardian.co.uk | 11 Jan 2010 | 12:00 am

The Curious Case of Potato Pareidolia

Over the holidays, an Ohio man named Dennis Bort cut a potato in half and was surprised to find the image of a cross inside. Any other time this might not have been remarkable, but during the Christmas season ...
Source: Discovery News - Top Stories | 10 Jan 2010 | 7:55 pm

Jenny McCarthy Dismisses Pediatrics Study on Autism

Earlier this week, research published in the peer-reviewed medical journal Pediatrics found no evidence that special diets have any influence on autistic children. This was a blow to some parents of autistic children who had hoped for a cure, but ...
Source: Discovery News - Top Stories | 10 Jan 2010 | 7:49 pm

UN 'wake-up call' on nature loss

The UN launches a Year of Biodiversity, warning that the on-going loss of species affects human well-being worldwide.
Source: BBC News | Science & Environment | UK Edition | 10 Jan 2010 | 6:30 pm

Water Drops Magnify Sunlight and Burn Leaves (LiveScience.com)

LiveScience.com - Many gardeners swear you should not water in the midday because water droplets on plants can magnify the sun's rays and burn leaves. But the idea has never been rigorously tested, until now.
Source: Yahoo! News: Science News | 10 Jan 2010 | 5:06 pm

In praise of… Michael Pollan

Few Britons know how to cook with high-­fructose corn syrup, a sweetener made by ­adding enzymes to corn starch. In the US, however, it is ubiquitous in processed food. Just as American farmers feed their cattle corn because the government subsidises it – and must dose cows so their stomachs can tolerate grain rather than grass – the US population is hooked on corn, for the worst of reasons. It was Michael Pollan who chronicled how this unhealthy state of affairs had come about in his 2006 book, The Omnivore's Dilemma, and how the industrialisation of agriculture has denuded soil, poisoned animals and helped to bring about the rise in type 2 diabetes. Not since Rachel Carson's The Silent Spring has a writer joined up agriculture, food and health in this compelling way, and nor have they gone on to expose the limitations of what Pollan calls "industrial organic" food. His idealism – he cooks a meal made up entirely of food hunted, gathered or grown by himself – and his rigorous research explains why Britain's campaigning chefs would have trouble emulating him. Perhaps aware that shooting dinner is a tough call outside the American wilderness, Pollan has written a digestible paperback, Food Rules: An Eater's Manual. It extends his manifesto into 64 injunctions, including "Buy a freezer" and "Don't eat breakfast cereal that changes the colour of the milk". Here's hoping that Pollan will go on to expose other perverse food chains that afflict the world's diet. How about the Common Agricultural Policy?

Source: Science news, comment and analysis | guardian.co.uk | 10 Jan 2010 | 5:05 pm

Letters: Dignity and nutrition for older people

The reported practice of forcing older people to have feeding tubes as a condition of admittance to a care or nursing home will be of great concern to those considering residential care, their families and staff (Care homes forcing elderly to have feeding tubes fitted, 6 January). It is unacceptable that an invasive clinical procedure should be a first line of care for those who find eating difficult. A better approach is surely to manage the way older people in care homes eat and drink. Having a good quality of life means fully participating in the sociable activities of meal times, which are often the highlight of people's days. Meal times are, for staff, an opportunity to demonstrate by caring words and actions that they respect residents' dignity. The Social Care Institute for Excellence's guidance on dignity and nutrition clearly states that the most effective services ensure that older people receive the time, help and encouragement they need in order to eat the food provided. We recognise that good nutrition management is a real challenge for staff and managers, but it is absolutely central to the provision of good care. Without it, residents' quality of life is severely damaged.

Allan Bowman

Chair, Social Care Institute for Excellence

• The requirement that elders have gastrostomies before being admitted to care homes is appalling. When, in 1987, I published with my colleague, Dr RH Fisher, an article that proposed that feeding tubes were dangerous in the ill, frail and elderly, my conviction was that they actually shorten life expectancy. The confidential study cited in your article appears to confirm that impression. Data from studies in 1999 and 2000 indicated that artificial feeding was futile in this group of patients, and the preponderance of evidence now is strongly against the use of tube feeding in the ill elderly. It is not even a "last resort", as has been described. It should not be used at all in the frail older person. To insist on its use is entirely for the convenience of staff with a complete lack of concern for the welfare of patients. I trust that some authority will be brought into play to stop this travesty immediately.

Dr I Campbell-Taylor

Clinical neuroscientist, New Waterford, Nova Scotia, Canada

• My mother-in-law, who has dementia, is in a nursing home being fed by caring nursing staff. She is totally "self-­funding", which requires that we draw £350 per week from her dwindling capital. If she had a tube fitted she would require "expert nursing care" and her care would be funded by the local authority. We have not asked for a tube to be considered, but one wonders what will happen when her capital has gone?

Clive Walker

Walton-on-Thames, Surrey

• Care homes which insist on feeding tubes are not using "person-centred care", a requirement of modern care services. It is the responsibility of the Care Quality Commission to inspect these homes and examine care plans to ensure they reflect a person-centred approach. This cannot be the case if so many unwarranted feeding tubes are being fitted. This is another failure in the regulatory system we have set in place for those who provide services to our most vulnerable citizens.

David Wood

Ulverston, Cumbria

• The Royal College of Physicians' report on the use of feeding tubes in care homes is fundamentally misleading. The claim that staff shortages necessitate artificial feeding suggests it is up to the care home provider to make this decision. It is not. "Peg" feeding is only utilised on the instruction of a consultant physician, and is a clinical matter. Its use is not in any way related to staffing numbers.

We look after over 10,000 residents in our care homes; only a very small minority have been prescribed artificial feeding and in all cases it has been appropriately undertaken by a physician. Our homes pride themselves on the quality of their cuisine, and our residents look forward to meal times. To direct the debate so as to cast a shadow on the integrity of the care providers misses the core clinical point.

Mike Parsons

Founder and CEO, Barchester Healthcare

Source: Science news, comment and analysis | guardian.co.uk | 10 Jan 2010 | 5:05 pm

Sparks fly at the Royal Institution as Greenfield sacked

In May 1802, three years after he led the foundation of the Royal Institution, the applied scientist Count Rumford left London under something of a cloud, never to return. Rumford – who gave the world the kitchen stove, the coffee pot and a wide-wheeled carriage, as well as a theory of heat – had brought together Britain's finest scientists in a state-of-the-art laboratory and lecture theatre in Albemarle Street. He believed the Royal Institution should turn science to industrial ends. Other members disagreed. Eminent scientists, such as that great Cornishman Humphry Davy, and later Michael Faraday, were drawn to fundamental research. "His high-handed and dogmatic ways provoked resistance," notes the Dictionary of National Biography, of Rumford's departure.

Roll forward two centuries, and the Royal Institution is once again at the centre of an unhappy dispute. Last Friday its director, Susan Greenfield, was made redundant. On Saturday she responded with a statement announcing that she planned to take legal action. The mess pits one of Britain's most outspoken scientists – a sharp, quotable and persuasive media star – against one of the country's most venerable scientific institutions. Her critics claim she mismanaged the RI, committing it to an overambitious expansion programme that has wrecked its finances, and that her departure is a prerequisite to the institution's recovery. Supporters respond that, as a high-profile woman in a profession dominated by men, she was a victim of sexism. They deplore the lack of scientific expertise among the people who removed her.

Lady Greenfield, garlanded with honours and made a people's peer by Tony Blair, is certainly the sort of scientist who makes other scientists jealous. The Fullerian professor of physiology at Oxford University has become a familiar media presence thanks to her worries about the effects of computer games and cannabis on human development. Her comments play along with popular anxieties about modern life. They go down badly with some scientists: the Guardian's Bad Science columnist Ben Goldacre has more than once called on her to publish her research, rather than use the authority of her position to make possibly unverifiable statements.

The Royal Institution has always championed the popular understanding of science as well as research (its Christmas lectures are now in their third century). Lady Greenfield continued the tradition. Her profile and manner were the reasons the RI appointed her. It is unfortunate that they now seem to be part of the reason she was removed. Science should be a cause of controversy and debate, but not of this kind. The manner of her dismissal is inexcusable; blame for the RI's perilous position should be shared.

Source: Science news, comment and analysis | guardian.co.uk | 10 Jan 2010 | 5:05 pm

Resurrecting dead dogs and making indestructible sandwiches

In the last of our mini Science Weeklies, Alok Jha is joined by special guest Mick O'Hare.

He's the editor of New Scientist's popular series of books with titles such as Does Anything Eat Wasps? and Why Don't Penguins' Feet Freeze?

The latest edition is called How to Make a Tornado and concerns the strange world of indestructible sandwiches, fake poo, resurrecting dead dogs – and many of the other odd things that scientists do in their quest for knowledge.

The rest of the team is back in the studio next week. In the meantime, have a listen and post your comments on the blog below, find us on Twitter and Facebook, and, if you're that way inclined, peruse our archive.

Source: Science news, comment and analysis | guardian.co.uk | 10 Jan 2010 | 5:01 pm

Water Drops Magnify Sunlight and Burn Leaves

Water droplets on certain plants can magnify the sun's rays and burn leaves.
Source: Livescience.com | 10 Jan 2010 | 5:00 pm

Southern US still coping with polar blast (AFP)

AFP - The southern United States on Sunday was bracing for more freezing temperatures, as the blast of polar air covering most of the country for the past week caused more fatal accidents on frozen lakes, rivers and ponds.

Source: Yahoo! News: Science News | 10 Jan 2010 | 3:45 pm

Claims of sexism at Royal Institution over Susan Greenfield treatment

Members question manner of removal and RI's ability to function without well-known scientist at its head

The Royal Institution was today accused of scapegoating, sexism, "injustice and skulduggery" over its treatment of Susan Greenfield, the high-profile neuroscientist who was suddenly removed as director of the institution last Friday.

The RI said it had taken the decision because its "requirement for the functions of the role of director as currently defined has ceased to exist".

But some members of the financially troubled institution have questioned the manner of Lady Greenfield's removal and the RI's ability to function without a well-known scientist at its head.

Greenfield, who is expected to file a sexual discrimination claim, said today that she could not comment. However, one RI member said that the Oxford scientist, 59, had been unfairly blamed for poor financial decisions made by others. "The notion that Greenfield somehow overspent resources and that the RI is in trouble as a result is specious."

He said it appeared that a trustee might have leaked incorrect material to the press. The member also said the membership was "outraged" over the way the chairman and trustees had behaved, adding: "There's been a lot of condescension, belittling and high-handedness, which reflects a rather brutal masculine attitude towards a vivacious woman. If Greenfield had been a man, these people would not have behaved [this] way.

"Greenfield has made vast improvements to what was a dusty old place and what we're seeing now are the remnants of that dust. This is an injustice."

There were concerns that the RI was being led by its chief executive, Chris Rofe, rather than a scientist: "It seems absurd that a national treasure, dedicated to the democratisation of science, should now be headed by a CEO without a science background."

Professor Lisa Jardine, a former member of the RI's governing council, said she did not believe the institution could function without a scientist in charge. "The post of director defines the RI and has done from [Michael] Faraday to Susan Greenfield," she said. "It has been always a charismatic scientist supported by a membership. If you remove the post of director … the RI does not exist any more."

Jardine, who sat on the council for five years, said it was wrong to blame managers at the RI for the state of its finances.

Roger Ashton-Griffiths, another member of the RI, claimed an attempt to restore harmony to the institution in late December had been shrugged off by the honorary secretary, Professor Alan Maries.

On 20 December, the requisite 15 members emailed Maries to ask for a special general meeting to consider a resolution calling on the RI's chairman and trustees to work harmoniously and in good faith with Greenfield and the RI staff.

However, Maries refused to pass on the request to the RI's president, the Duke of Kent, citing the RI byelaw which stipulates requests must be submitted "in writing" on paper and contain the 15 signatures.

Ashton-Griffiths said he and his fellow signatories were angry that the chairman and the trustees appeared to have entirely ignored their concerns when deciding to remove Greenfield from her post.

Although Greenfield's 12 years as director of the RI have helped the institution modernise its image and raise its profile, they have also invited controversy. Last February, she told the House of Lords that social networking sites risked infantilising young minds, leaving them with short attention spans, an "inability to empathise and a shaky sense of identity".

In a statement released on Friday, the RI said it had decided to abolish the role of director following a governance review, and paid tribute to the "leading role" that Greenfield had played at the RI.

Rofe referred the Guardian to the statement, adding that he was unable to respond to the allegations. He said: "As Baroness Greenfield has indicated that she is going to sue the RI we cannot comment on legal matters."

Source: Science news, comment and analysis | guardian.co.uk | 10 Jan 2010 | 3:40 pm

California Earthquake Good Practice for Tsunami

Saturday afternoon, residents of northern California were violently shaken by a magnitude 6.5 earthquake not far offshore in the Pacific Ocean. Much of the area is without power after electrical lines snapped in the quake, and in some places damage ...
Source: Discovery News - Top Stories | 10 Jan 2010 | 3:32 pm

Largest U.S. farm group rallies against climate bill (Reuters)

Reuters - The largest U.S. farm group will oppose aggressively "misguided" climate legislation pending in Congress and fight animal rights activists, said American Farm Bureau Federation president Bob Stallman on Sunday.

Source: Yahoo! News: Science News | 10 Jan 2010 | 2:42 pm

Spain begins to flood park with peat fire (AP)

AP - Hoping to save a dried Spanish wetland from an underground peat fire, the government has unleashed floodwaters onto an expanse of the marsh now under threat due to past water mismanagement.

Source: Yahoo! News: Science News | 10 Jan 2010 | 1:49 pm

Irrational fears give nuclear power a bad name, says Oxford scientist

Wade Allison says misplaced health stigma has prevented the full benefits of nuclear energy being explored

The health dangers from nuclear radiation been oversold, stopping governments from fully exploiting nuclear power as a weapon against climate change, argues a professor of physics at Oxford University.

Wade Allison does not question the dangers of high levels of radiation but says that, contrary to scientific wisdom, low levels of radiation can be easily tolerated by the human body.

Most scientists who have responded disagreed with Allison's conclusions, but his comments have highlighted the lack of understanding of how the body deals with low doses of radiation, a crucial issue given it is increasingly used in modern medical procedures such as scanning and cancer treatment.

Nuclear crises, from the bombing of Hiroshima and Nagasaki to the meltdown of a nuclear reactor at Chernobyl, have created widespread fear and distrust of nuclear power, and global pressure to keep radiation at the lowest possible level, according to Allison, a particle physicist who makes his arguments in a self-published book, Radiation and Reason. He says long-term data on the health of survivors of the atomic bombs have demonstrated how good the human body is at protecting itself from radiological and chemical attack.

"The ability to repair damage and replace cells, we discovered in the last 50 years, show how radiation doesn't cause damage except under extreme circumstances," he says. "The radiation that a patient gets in one day from a course of radiotherapy treatment, it would take a million hours of exposure for someone standing in the radioactive waste hall of Sellafield. And, if you have radiotherapy, it goes on for several weeks."

Ionising radiation, the type from nuclear reactions, can break strands of DNA in cells and these can make a cell cancerous unless the body's machinery can fix the damage. Scientists have used data from Hiroshima and Nagasaki, plus that from experiments on animals and cell cultures, to create a measure of how much damage is caused by high levels of radiation. This has then been extrapolated back, in a straight line, to estimate the potential damage from low levels of radiation to create what is called the linear non-threshold (LNT) model.

"The problem with a lot of these discussions is that you eventually get to the point where you don't have any more data," said Professor Gillies McKenna of Oxford University, Cancer Research UK's expert on radiation oncology. "Even the data from Hiroshima and Nagasaki – there weren't enormous numbers of cancers created in those cases, so we have to extrapolate what we think would happen at low dose."

Since the end of the second world war, scientists have worked on the basis that there is no dose of radiation so low that it is not dangerous. Allison, however, believes there is a threshold below which any radiation exposure is fully repaired by the body – but this is a view mainstream scientists disagree with.

"I wouldn't say Allison's ideas are fanciful but when you weigh up all the evidence, the scientific authorities come to the conclusion that the LNT dose-response relationship for low doses is the best we can do," says Richard Wakeford, an epidemiologist specialising in the health effects of radiation at the University of Manchester.

Allison's hypothesis assumes that all of the DNA damage caused below a threshold of radiation dose can be fixed by the cells' internal machinery. "I can't see and nor do the majority of experts in the field how these processes can be 100% effective," said Wakeford.

"Radiation is particularly effective at causing double-strand DNA breaks, which make it difficult for the repair mechanisms in the cells to repair them properly."

Where McKenna and other scientists do agree with Allison is that fear of radiation is a problem. McKenna's expertise is in the use of radiation to kill cancer cells. "People become so fearful of radiation that they avoid diagnostic tests that might save their lives or avoid radiotherapy when they have cancer that is much more likely to kill them than exposure to radiation. He [Allison] is right that it has become a little bit hysterical. People are now avoiding CT scans or avoiding building nuclear power stations when in most aspects, radiation is a very useful thing."

Half of cancer patients will be given radiotherapy and more than half of those will be cured by it, McKenna said. "In most instances, where you use radiation – certainly in medicine and in most other forms of industry – the benefits greatly outweigh the risks."

Treatment involves a dose of radiation directed at the cancer cells which is 10 to 20 times the dose that would be fatal directed to the whole body.

Some areas of the country, such as Devon and Cornwall, have naturally high levels of radiation in the rock, and yet they do not have high incidence of cancer. "It would suggest to me that we can tolerate relatively higher doses of radiation, unless you add things on top like smoking," said McKenna, adding that there were good scientists on both sides of the debate, "but you reach a point where you can't generate the data you need and I do think we need to be careful not to exaggerate the risks and increase the fears."

Nothing has generated quite as much cancer concern in the UK as Sellafield power station in Cumbria. Concern about radiation leaks at the plant, known as Windscale when it was commissioned in 1956, grew over the years until in 1983, Yorkshire Television produced a documentary called The Nuclear Laundry, suggesting low-level radiation emissions posed a risk. In the 1990s clusters of childhood leukaemia cases were identified near the site.

Investigating those concerns has been the preoccupation of Comare, the government's expert committee on the medical aspects of radiation, since it was set up in 1985. After years of painstaking work and many reports, it has yet to establish a link between radiation and childhood leukaemia. The evidence for some sort of infection, possibly caused by the movement from one area to another of people working at the plant, is far stronger.

Comare's chairman, Alex Elliott, a professor of clinical physics at Glasgow University, says there is a wide spectrum of views on the dangers of low-level radiation. "There are those who believe people like me are part of an international conspiracy to hide the dangers of radiation from the public," he said. At the other end are the believers in "radiation hormesis", who say we live in a beneficent soup of low-dose radiation, which is essential for life and may even prevent cancer deaths.

Elliott steers a middle path. "The Comare view, along with the consensus worldwide, is that the current risk estimates are broadly correct," he said. "They keep being revised but if they are wrong, it is by no more than a factor of two or three in each direction." And, he said, "we believe the linear hypothesis should continue to be used."

It is almost impossible, he said, to carry out experiments that would prove that low-level radiation is dangerous or is not, because the risks are so small.

But radiation generates fear, he said. "Because we can't see, hear, smell or touch it, we are much less tolerant of radiation than anything else. We are definitely hysterical about radiation. We go to enormous lengths on the precautionary principle.

"I don't know how many people are killed on the roads each year, but we live with that. We're not thinking of banning trucks. We're incredibly bad at risk-benefit analysis."

But Wakeford said that calculating the risks of low-level radiation is becoming increasingly important. "One of the big issues today is just how you manage these new, relatively high-dose diagnostic procedures like CT scans. This is probably the big issue as far as low doses are concerned. In the US, remarkably, the average citizen receives more dose from medical diagnostic procedures than he receives from background radiation, which is a dramatic increase from the last time this was assessed about 20 or so years ago. When you come to make an assessment about balance of risk about whether to give a child a CT scan or not, these are real considerations, not hypothetical at all."

Comare, in a rare respite from studying leukaemia clusters at nuclear installations, recently produced a hard-hitting report on sunbeds, calling for a ban on their use by under-18s. "At the minute, it would appear that more people are damaged by sunbeds than by nuclear power in the UK," Elliott said.

Reasons to be fearful? Expert views

Mike Clark, scientific spokesman for the Health Protection Agency

"There is an international scientific consensus about the health effects of ionising radiation which is based on decades of research worldwide. This is the so-called linear hypothesis, by which you extrapolate health effects observed at high doses to calculate risks at low doses. There are scientists who disagree with this and clearly Professor Allison is one of them. However there are also some scientists who claim the linear hypothesis can underestimate risks.

"The Health Protection Agency accepts the scientific consensus and bases its advice on recommendations from the International Commission on Radiological Protection."

Professor Steve Jones of Westlakes Research Institute, who published research on the health of the former British Nuclear Fuels workforce and the link between high radiation doses and heart disease

"One of the problems, is that the effect of radiation at low doses is very difficult to determine from observational science because the effects are small. The cancer risk to any group of people over a lifetime is 25% and if you look at whether radiation will increase over that you will struggle to get a clear result. Another reason to be cautious is because some studies suggest that the risk of radiation may be an increase in circulatory diseases as well. A good judgement based on all the scientific information available is it would be unwise to move away from what we have."

Richard Wakeford, visiting professor of epidemiology at the University of Manchester

"I do not find [Allison's] these arguments particularly convincing. I have to say, when I've reviewed the evidence, it is very difficult to detect the adverse effects of radiation at low levels because the predicted excess risk of cancer is small and is easily hidden in the noise of other factors like smoking and diet and drinking. All the people who hang on to these arguments are missing the point. If you take the evidence as a whole from radiation epidemiology, there's probably a risk from cancer arising from small doses of radiation [and] they're around about what you get from a linear no-threshold dose response."

Susan Short, clinical senior lecturer in oncology at University College London

"I do have sympathy with the view that the effects of radiation have been overestimated but it reflects ignorance in the community about radiation; it's still portrayed as a dangerous unknown though we understand a lot about it really. People have such poor understanding of risk – these people who go and demonstrate against local nuclear power plants are the same as those who will happily smoke 20 cigarettes a day or lead high-risk lifestyles and don't see the irony."

Source: Science news, comment and analysis | guardian.co.uk | 10 Jan 2010 | 1:32 pm

On the beat: Scientists spot genes for heart rhythm (AFP)

AFP - Researchers on Sunday said they had identified more than a dozen genes that help modulate heart rate, a finding that one day may lead to smarter cardiac drugs.

Source: Yahoo! News: Science News | 10 Jan 2010 | 12:14 pm

Egypt discovers new workers' tombs near pyramids (AP)

AP - Egyptian archaeologists discovered a new set of tombs belonging to the workers who built the great pyramids, shedding light on how the laborers lived and ate more than 4,000 years ago, the antiquities department said Sunday.

Source: Yahoo! News: Science News | 10 Jan 2010 | 11:31 am

Crow tries to ride to rescue of wild horses (AP)

AP - Sheryl Crow has spoken out against the war in Iraq and in support of embryonic stem-cell research and efforts to combat global warming. Now, she's trying to ride to the rescue of thousands of wild horses that roam the West.
Source: Yahoo! News: Science News | 10 Jan 2010 | 11:01 am

Why Bright Light Worsens Migraine Headache Pain

Relief form migraine headaches could result from study that shows why light increases pain.
Source: Livescience.com | 10 Jan 2010 | 11:00 am

Solving an ice age mystery

People who study the behavior of Earth's climate have been pondering a mystery of the last ice age. Why did the size of the Northern ice sheets fluctuate so dramatically, pushing global sea level up and down? Many suspected a ...
Source: Discovery News - Top Stories | 10 Jan 2010 | 11:00 am

Egypt tombs suggest pyramids not built by slaves

CAIRO (Reuters) - New tombs found in Giza support the view that the Great Pyramids were built by free workers and not slaves, as widely believed, Egypt's chief archaeologist said on Sunday.
Source: Reuters: Science News | 10 Jan 2010 | 10:30 am

More Abundance by Owning Less

Less is more; let the music show you how. We've witnessed the progression: albums to compact discs to digital files a la iTunes, where each step takes less material and less effort to get the music to the listener. Now, ...
Source: Discovery News - Top Stories | 10 Jan 2010 | 7:04 am