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PET Can Measure Effectiveness Of Novel Breast Cancer TreatmentPositron emission tomography scans in mice can be used to determine whether a novel type of breast cancer treatment is working as intended, study shows.Source: ScienceDaily: Latest Science News | 9 Jul 2009 | 6:00 pm Is Obesity An Oral Bacterial Disease?Scientists have discovered new links between certain oral bacteria and obesity. In a recent study, the researchers demonstrated that the salivary bacterial composition of overweight women differs from non-overweight women. This preliminary work may provide clues to interactions between oral bacteria and the pathology of obesity. This research may help investigators learn new avenues for fighting the obesity epidemic.Source: ScienceDaily: Latest Science News | 9 Jul 2009 | 6:00 pm Language Skills In Your Twenties May Predict Risk Of Dementia Decades LaterPeople who have superior language skills early in life may be less likely to develop Alzheimer's disease decades later, despite having the hallmark signs of the disease, according to new research.Source: ScienceDaily: Latest Science News | 9 Jul 2009 | 6:00 pm Beyond Carbon Dioxide: Growing Importance Of Hydrofluorocarbons (HFCs) In Climate WarmingSome of the substances that are helping to avert the destruction of the ozone layer could increasingly contribute to climate warming, according to scientists.Source: ScienceDaily: Latest Science News | 9 Jul 2009 | 6:00 pm Better Than A Hearing Aid? Better Hearing With Bone Conducted SoundNew technology to hear vibrations through the skull bone has been developed. Besides investigating the function of a new implantable bone conduction hearing aid, researchers have studied the sensitivity for bone conducted sound and also examined the possibilities for a two-way communication system that is utilizing bone conduction in noisy environments.Source: ScienceDaily: Latest Science News | 9 Jul 2009 | 6:00 pm Easter Island Compound Extends Lifespan Of Old Mice: 28 To 38 Percent Longer LifeResearchers report that rapamycin, a compound first discovered in soil of Easter Island, extended the expected lifespan of middle-aged mice by 28 percent to 38 percent. In human terms, this would be greater than the predicted increase in extra years of life if cancer and heart disease were both cured and prevented.Source: ScienceDaily: Latest Science News | 9 Jul 2009 | 6:00 pm Ice Volume Of Switzerland’s Glaciers CalculatedSwitzerland's glaciers have lost twelve percent of their ice volume since 1999. The water stored in Switzerland's glaciers currently equates to about two thirds of the volume of Lake Geneva.Source: ScienceDaily: Latest Science News | 9 Jul 2009 | 3:00 pm Inflammation May Trigger Alzheimer's DiseaseNew research sheds light on what causes Alzheimer's disease and suggests a possible therapy.Source: ScienceDaily: Latest Science News | 9 Jul 2009 | 3:00 pm Giant Supernovae Farthest Ever Detected: Dying Stars Shed Light On Universe Formation 11 Billion Years AgoUC Irvine cosmologists have found two supernovae farther away than any previously detected by using a new technique that could help find other dying stars at the edge of the universe.Source: ScienceDaily: Latest Science News | 9 Jul 2009 | 3:00 pm Toxic Chemicals Affect Steroid Hormones Differently In Humans And InvertebratesIn a study with important consequences for studies on the effects of chemicals on steroid responses in humans, scientists have found that -- contrary to earlier assumptions -- enzymes used for the synthesis of steroids in insects, snails, octopuses and corals are unrelated to those used in humans.Source: ScienceDaily: Latest Science News | 9 Jul 2009 | 3:00 pm G8 eyes climate as summit includes emerging powers (Reuters)
Source: Yahoo! News: Science News | 9 Jul 2009 | 9:38 am Crew start cutting St Kilda wreckA salvage team begins dismantling piece-by-piece a trawler that wrecked on St Kilda more than a year ago.Source: BBC News | Science & Environment | UK Edition | 9 Jul 2009 | 9:03 am Scientists hope tiny insect can help save soybeans (AP)AP - An insect no bigger than a comma is being studied as a natural predator that farmers could use instead of chemicals to protect the nation's soybean crop from aphids.Source: Yahoo! News: Science News | 9 Jul 2009 | 7:51 am Global warming impacting Greenlanders' daily lives (AFP)
Source: Yahoo! News: Science News | 9 Jul 2009 | 6:13 am Jellyfish are swarming in the warm weather, say marine expertsMarine experts say warm weather has prompted reports of large numbers of jellyfish in the waters around Scotland.Source: BBC News | Science & Environment | UK Edition | 9 Jul 2009 | 5:59 am British scientists claim to create human sperm (AP)
Source: Yahoo! News: Science News | 9 Jul 2009 | 5:10 am NASA poised for third shuttle launch try SaturdayCAPE CANAVERAL, Florida (Reuters) - Countdown clocks resumed ticking at the Kennedy Space Center in Florida on Wednesday in preparation for NASA's third attempt to launch space shuttle Endeavour on a construction mission to the International Space Station.Source: Reuters: Science News | 9 Jul 2009 | 3:00 am NASA poised for third shuttle launch try Saturday (Reuters)
Source: Yahoo! News: Science News | 9 Jul 2009 | 2:35 am Transplant drug helps mice live longerWASHINGTON (Reuters) - An antibiotic pill originally developed to help prevent rejection in organ transplant patients helps mice live longer and might offer a route to fighting age-related disease in people, U.S. researchers reported on Monday.Source: Reuters: Science News | 9 Jul 2009 | 1:55 am Drug helps monkeys, rabbits survive anthraxCHICAGO (Reuters) - An experimental antibody treatment helped rabbits and monkeys survive a deadly dose of anthrax bacteria and proved safe in humans, too, researchers at Human Genome Sciences said on Wednesday.Source: Reuters: Science News | 9 Jul 2009 | 1:49 am Humans Ate Fish 40,000 Years Ago (LiveScience.com)LiveScience.com - At least one of our ancestors regularly ate fish 40,000 years ago, a new study finds.Source: Yahoo! News: Science News | 9 Jul 2009 | 1:35 am Historic Atom Smasher Reduced to Rubble and Revelry<< previous image | next image >>
BERKELEY, California — What was once the world’s biggest atom smasher will soon be nothing more than a collection of old photos and the dust beneath the next big science machine. Lawrence Berkeley National Laboratory’s Bevatron, built by the Atomic Energy Commission for $9 million in the early ’50s, is slowly being demolished in the hills overlooking San Francisco Bay. In a few years, all traces of it will be gone. The Bevatron was a marvel, that, when compared to the rest of the human world drew ridiculous comparisons. Popular Science called it a “10,000-Ton Cracker for Invisible Nuts” and rapturously listed its dimensions. For boys of all ages, the Bevatron’s stats were the 36-24-36 of physics. “It is 135 feet across, cost $9,500,000 and contains more than 9,500 tons of iron, 225 miles of wire, and 2,400 vacuum tubes,” wrote Darrell Huff in Popular Science. “This is the bevatron, just completed, the most powerful atom-smasher yet built.” Continue reading below 
Top photo: Lawrence Berkeley Lab
Source: Wired: Wired Science | 9 Jul 2009 | 12:13 am Study pinpoints UK wind hotspotsAn Energy Saving Trust study identifies the 'best and worst' locations in the UK for domestic small-scale wind turbines.Source: BBC News | Science & Environment | UK Edition | 9 Jul 2009 | 12:04 am Astronaut Gets Honorary Degree in Space (SPACE.com)SPACE.com - A Canadian astronaut orbiting Earth received an honorary degree - a first in space - on Wednesday during a long-distance call from his college alma mater.Source: Yahoo! News: Science News | 8 Jul 2009 | 11:15 pm From pythons to fungus, species invading US (AP)
Source: Yahoo! News: Science News | 8 Jul 2009 | 11:14 pm Can sperm really be created in a laboratory?Anybody who has, for whatever reason, dreamed of a world without men in the past probably looked to the cloners to make it happen. Few would have imagined it might one day be possible to create human sperm in a laboratory, but that is now the proud claim of Professor Karim Nayernia of the North East England Stem Cell Institute. It is a claim that immediately hit controversy. Allan Pacey of the University of Sheffield, a sperm biologist of 20 years standing, declared he was unconvinced. Azim Surani, a professor of physiology and reproduction at Cambridge University, said they were "sperm-like cells" and "a long way from being authentic sperm cells". Reactions two years ago, when the same team not only grew mouse sperm from embryonic cells but used it to produce baby mice, were somewhat warmer, which perhaps says something about the sensitivities around the creation of human sperm. Pacey said at the time that the mouse experiment would be "very useful to study the basic biology of sperm production". Using technology to produce the essence of human life is a sensitive matter: the baby mice all died after a few months. And while the Newcastle scientists have categorically ruled out the use of their manufactured sperm for reproduction and say they understand people's concerns, the very notion that human sperm have been created from stem cells has taken anxieties to a new level. "The law specifically does not allow artificially created sperm to be used to fertilise an egg for the sake of reproduction," says Professor Peter Braude, head of the department of women's health in the division of reproduction and endocrinology at King's College London. And even if the law is changed, he asks, "What experiments are you going to do to make it safe?" Citing Dolly the Sheep, Braude points out that cloning has been shown to be unsafe, and there's no reason to suppose lab-created sperm will be any safer. Still, all the experts say what has been done in Newcastle is interesting and good for research. Discovering how to make sperm will teach us more about sperm malfunction, and therefore could help treat infertile men, rather than replace them. The Newcastle team used stem cells from a leftover embryo donated after fertility treatment, and used chemicals to encourage their growth. They could not use just any kind of stem cells, however. They selected only those with the potential to become sperm - the so-called "germline" cells, which were a small proportion of the total. Over four to six weeks, these cells developed and were prompted to undergo the process of "meiosis", which halved the number of chromosomes they carried - a hallmark of sperm. The woman's egg must contribute the rest of the chromosomes needed by an embryo. Interestingly, the team's success came from stem cells with XY (male) chromosomes. The same process on XX (female) stem cells did not work, which seems to suggest that the male of the human species is not yet wholly superfluous. guardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds
Source: Science news, comment and analysis | guardian.co.uk | 8 Jul 2009 | 11:01 pm In praise of ... Ian GibsonBy most measures, Ian Gibson was one of the more impressive members of the House of Commons. He was, for a start, one of the few scientists to win a seat, a biologist in a chamber packed with lawyers, teachers and political professionals. His expertise was useful: he had an interest in climate change and asked the questions that needed to be asked on everything from food security to illegal drugs. He attended more votes than most MPs and often showed independence of mind, opposing the Iraq war on five occasions, as well as voting against ID cards, Trident renewal and draconian anti-terror legislation. Yet he did not (unlike some colleagues) oppose his party for the sake of it. He picked his issues with care. He also claimed less in expenses than many MPs - his most recent claim was lower than 456 others. That did not save him when it was revealed that he had first let his daughter live, rent-free, in a flat largely paid for out of expenses, and then sold it to her for below market value. A Labour party committee ruled that he could not stand again at the next election, which led Mr Gibson to resign his seat immediately. There is irony in the fact that the first MP to leave the Commons over his expenses was by no means the worst offender - and by selling his flat at a discount, Mr Gibson, not the taxpayer, was left out of pocket. Some in his former Norwich North seat hoped he would stand in this month's byelection. Nominations closed yesterday, confirming that he will not, but he will be missed. guardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds
Source: Science news, comment and analysis | guardian.co.uk | 8 Jul 2009 | 11:01 pm Tests raise life extension hopesA compound discovered on the South Pacific's Easter Island may help to fight the ageing process, research suggests.Source: BBC News | Science & Environment | UK Edition | 8 Jul 2009 | 11:00 pm Nun Brains Show Language Skills Predict Future Alzheimer’s Risk
Superior language skills in your late teens and early twenties may actually protect you from dementia many decades later, according to a new study of 38 Catholic nuns who donated their brains to science. Researchers from the Johns Hopkins School of Medicine compared nuns with normal cognitive function at the end of life with those who had mild dementia or full-blown Alzheimer’s. By studying the nuns’ autobiographical writings from their early lives, the scientists found that regardless of evidence of Alzheimer’s in the brain, sisters who had better language abilities early in life were less likely to exhibit symptoms. “If you had these high language skills when you were a teenager, you were able to decrease the chance of getting dementia 50 or 60 years later,” said neuropathologist Diego Iacono, a co-author on the paper published Wednesday in Neurology. This was true even if there is a significant amount of damage in the brain. One of the most puzzling aspects of Alzheimer’s disease is why some people get it and others don’t. Scientists have identified specific physical signs in the brain associated with the disease, such as plaques and tangles of a protein called beta-amyloid, but not everyone who has the plaques actually gets sick. “There’s a special group of people who at autopsy have the same amount of pathology in the brain, but for some reason don’t show any clinical manifestations of the disease,” Iacono said. In a previous study of mostly male patients, the researchers found that patients with this so-called “asymptomatic Alzheimer’s” had larger neurons in the memory regions of their brain, possibly indicating a protective response to the pathologic accumulation of protein in their brain. The researchers hoped to confirm their earlier finding in a second population that included women. Because of the unique data available from the Nun Study, an ongoing research project following 678 Catholic nuns born before 1917, the scientists also had the opportunity to look at early language ability and its effect on the development of Alzheimer’s.
After beginning the project, the founders of the Nun Study discovered essays written by some of the sisters in their late teens and early twenties, and analyzed the works for their verbal prowess, such as idea density and grammatical complexity. “There’s no other study in the world that has similar data,” Iacono said. “They found these autobiographies by chance. So now, years after the essays were written, we can correlate language abilities from 50 or 60 years ago with level of disease at the end of life.” Nuns who never developed memory problems scored 20 percent higher on idea density than those who became symptomatic, but there was no difference in grammar score between the two groups. The researchers say they don’t know exactly why superior language abilities appear to be protective against dementia, but they expect it has something to do with forming more synapses during early life. “It’s the first time that we show in humans that such a complex cognitive activity like idea density or language is connected with a neurodegenerative disease,” Iacono said. “Something that’s related to not only the molecules, but also the function of the brain.” Studies of the nuns from 1996 and 2001 had shown a connection between early language skills and the likelihood of developing dementia, but this was the first time researchers focused on nuns who had normal memory despite signs of Alzheimer’s at autopsy. This time around, since more nuns had died, the researchers also had more brains to look at. “Now with this kind of paper, we have shown that we should focus not only on what we can see in the brain, but also on what we cannot see, the connection between cognition and pathology,” Iacono said. “Our suspicion is that this is just the tip of the iceberg — there’s so much that we still don’t know about neural disease and the genesis of dementia.” See Also:
Image: Flickr/audreym
Source: Wired: Wired Science | 8 Jul 2009 | 9:48 pm Drug helps monkeys, rabbits survive anthrax (Reuters)Reuters - An experimental antibody treatment helped rabbits and monkeys survive a deadly dose of anthrax bacteria and proved safe in humans, too, researchers at Human Genome Sciences said on Wednesday.Source: Yahoo! News: Science News | 8 Jul 2009 | 9:08 pm Obama names geneticist to lead health agency (AFP)
Source: Yahoo! News: Science News | 8 Jul 2009 | 8:56 pm Magnetic ‘Thinking Cap’ Improves Learning
“Thinking cap” is far easier to say than “excitatory repetitive transcranial magnetic stimulation,” but the message is the same: a helmet that helps people learn. For the moment, learning is restricted to tracking on-screen targets in the laboratory of physical therapist Lara Boyd at the University of British Columbia. But her brain-tingling technique might eventually help stroke victims recover their coordination. In an experiment published Tuesday in BMC Neuroscience, Boyd put 30 people into a machine that sent electromagnetic waves into their premotor cortexes, a brain region associated with learning motor skills. Afterwards, test subjects used a joystick to track a moving target. Sometimes its movements were random, and sometimes they were repeated. After four days of tests, subjects who received a full dose of brain stimulation were better at tracking repeated patterns than those who received a low dose, or none at all. Each group fared equally poorly at random tracking, suggesting that improvements could be explained by enhanced learning abilities, rather than changes in overall motor skills. Boyd suspects that stimulation helps neurons in the premotor cortex form connections, allowing motor memories to form rapidly. See Also:
Citation: “Excitatory repetitive transcranial magnetic stimulation to left dorsal premotor cortex enhances motor consolidation of new skills.” By Lara A Boyd and Meghan A Linsdell. BMC Neuroscience, Vol. 10, No. 72. July 7, 2009. Image: Lara Boyd Brandon Keim’s Twitter stream and reportorial outtakes; Wired Science on Twitter.
Source: Wired: Wired Science | 8 Jul 2009 | 6:37 pm Urine: A 'Clean' Energy SourceCars, homes and portable electronic devices could all be powered by urine.Source: Discovery News Top Stories : Discovery Channel | 8 Jul 2009 | 5:50 pm Moon musicFormer Roxy Music member Brian Eno is known as the father of ambient music. To celebrate the 40th anniversary of the Apollo 11 moon landing, he will introduce the first live performances of his 1983 composition Apollo: Atmospheres and Soundtracks at the Science Museum, London, on 20 and 21 July In 1983, Brian Eno released an album inspired by Apollo 11. It has now been reworked for its first live performance. Here he talks to Roger Highfield, the editor of New Scientist, about the project. Prize drawWould you like to see Brian Eno's Apollo performed at the Science Museum in London? New Scientist has five pairs of tickets to give away. Email your name, address and phone number to competition@newscientist.com. The first five entries out of the hat will win. You must make your own travel arrangements. The closing date is 5pm on 16 July. For terms and conditions see http://www.newscientist.com/info/in312 This interview appears in the latest issue of New Scientist magazine guardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds
Source: Science news, comment and analysis | guardian.co.uk | 8 Jul 2009 | 5:31 pm Cancer Drug Delays Aging in Mice
In a potentially landmark study on the biology of aging and how to delay it, a drug gave elderly mice the human equivalent of thirteen extra years of life. Though the drug is an immune system suppressant that almost certainly won’t have the same effect in humans, the study provides compelling evidence that pharmacologically slowing the process of aging itself may be possible. “It’s unlikely that the life extension came from merely postponing a few specific diseases,” said Jackson Laboratory gerontologist David Harrison, a leader of one of three research teams who conducted the experiment separately. “And the treatment didn’t start until the mice were the equivalent of a 60-year-old human. No other intervention has been so effective starting late in life.” The drug, called rapamycin, was originally found in bacteria from Easter Island. It showed promise for slowing cell growth, leading to its development as an immunosuppressant used to treat cancer and reduce organ transplant rejection. That ability also made rapamycin a candidate for research into the mechanisms of aging. Gerontology itself is a youthful field, its progress having been slowed by aging’s daunting complexity and a tendency among scientists and doctors to consider diseases as entirely separate, rather than as manifestations of a common origin. But in recent years, that thinking has started to change. From diabetes to cancer to dementia, many diseases become steadily more likely with advancing age. Their common risk profile hints at common origins.
Enticing research also comes from studies of caloric restriction. When animals are given the bare essentials of nutrition, biological mechanisms are triggered that lengthen their lives and slow disease development. Researchers have investigated the biology behind this effect, hoping to find non-dietary ways of getting the same results. One promising class of compounds target sirtuins, a family of genes that are activated by caloric restriction, and regulate the function of mitochondria — cellular power generators whose dysfunction has been linked to many diseases of aging. Among these compounds is resveratrol, which has displayed powerful protective effects in animals, and is now being tested as a diabetes drug in people. But at least in mice, even resveratrol hasn’t proven as powerful as rapamycin, which targets a gene that’s central to the regulation of cell growth and development. And though the latest findings, published Wednesday in Nature, represent an early stage of research — following on yeast and roundworm and fruit fly tests, and very far from applicable to humans — they’re still strong. “There’s no obvious way to turn this into a lifespan extension for humans,” said David Sinclair, a Harvard gerontologist not involved in this study. “But it’s clearly a milestone in the field, to be able to use one small molecule to have such a big effect in an animal. Twenty years ago, if you suggested that one small molecule could slow down aging, people would have said it was impossible.” Harrison, Sinclair and other researchers all warned any benefits rapamycin might have in humans would be offset by its immune system-suppressing effects; unlike lab mice, humans don’t live in sterile, rigorously controlled environments. But the new study shows that rapamycin is still a useful tool for investigating aging. Results were replicated independently in three different laboratories. Mice were already old when they started treatment. They were also genetically diverse, ensuring that mice would die in many different ways, and requiring any potential anti-aging drug to have a truly broad effect. “If you’re going to make a claim that you’re actually postponing aging, you really need to be showing that it has beneficial effects on total lifespan in a wide variety of genotypes,” said Harrison. “You have to limit your claim to what you’ve done. The experiment here was designed to allow us to make claims about basic factors of aging.” More than 1,900 mice, their total genetic variation roughly comparable to that found in humans, were fed rapamycin. Treatment starting when they were around 20 months old, a stage comparable to early old age in people. The average date at which 90 percent of the mice were dead — a convenient metric for quantifying lifespan — rose from 1,078 days to 1,179 days in males, and from 1,094 days to 1,245 days in females. In proportional terms, old age lasted one-quarter longer than expected for males, and two-fifths longer for females. When tested on nine-month-old mice, rapamycin had little effect. “It’s possible that for some agents, the most beneficial effect will only start late in life,” said Harrison. Steven Austad, a University of Texas gerontologist who has been skeptical about resveratrol’s apparent longevity-enhancing effects, called the results “particularly significant.” He said the multi-center study design gave them “instant credibility.” “If they had asked me, I would have suggested to forget even doing this experiment as the animals were too old to show any effect,” said Austad. “Boy, was I wrong about that.” How rapamycin works remains only hazily understood. Its target — a gene called mTOR, short for mammalian target of rapomycin — produces an enzyme necessary for triggering a cascade of cellular signals involved in regulating cell growth, breakdown and mitochondrial function. Some evidence suggests that mTOR’s pathway shares many functions and genes with the sirtuin pathway targeted by resveratrol. The extent of the overlap is unclear, but both appear to be involved in processes affected by caloric restriction. “There are only a handful of really crucial pathways that control lifespan,” said Sinclair. “These pathways all talk to each other. You can think of them not as separate, but as part of a larger network of pathways that are communicating and working in concert.” Future studies on rapamycin and mTOR will work backwards from the general effect to specific mechanisms, said Harrison. He mentioned immune response, cellular breakdown and glucose metabolism as immediate areas of research focus, and in his own laboratory plans to study rapamycin’s effects on stem cells. For now, what explains the long lives of the mice remains an open research question. “The bottom line is, we can guess, but we don’t know,” said Harrison. See Also:
Citations: “Rapamycin fed late in life extends lifespan in genetically heterogeneous mice.” By David E. Harrison, Randy Strong, Zelton Dave Sharp, James F. Nelson, Clinton M. Astle, Kevin Flurkey, Nancy L. Nadon, J. Erby Wilkinson, Krystyna Frenkel, Christy S. Carter, Marco Pahor, Martin A. Javors, Elizabeth Fernandez & Richard A. Miller. Nature, Vol. 460, No. 7252 “A midlife longevity drug?” By Matt Kaeberlein and Brian K. Kennedy. Nature, Vol. 460, No. 7252 Image: Imperial College London Brandon Keim’s Twitter stream and reportorial outtakes; Wired Science on Twitter.
Source: Wired: Wired Science | 8 Jul 2009 | 5:02 pm United Fractal Laws Offer Better PredictionsThe united laws can help predict anything from disease spread to internet traffic.Source: Discovery News Top Stories : Discovery Channel | 8 Jul 2009 | 4:00 pm Coral and Brittle Star: 'Til Death Do Us PartBrittle stars attach to this coral, forever.Source: Livescience.com | 8 Jul 2009 | 3:16 pm BLOG: New Monkey Discovered in BrazilThe new monkey, "Mura's saddleback tamarin," was found in a remote part of the Amazon.Source: Discovery News Top Stories : Discovery Channel | 8 Jul 2009 | 2:00 pm Agencies outline Mars initiativeThe US and European space agencies launch an initiative that could lead to joint missions to explore the Red Planet.Source: BBC News | Science & Environment | UK Edition | 8 Jul 2009 | 1:30 pm Sperm Travels Faster Toward Attractive FemalesThe chances of fertilization increase when the female is deemed to be desirable.Source: Discovery News Top Stories : Discovery Channel | 8 Jul 2009 | 1:30 pm False dawnFinland's nuclear vision hit by delays and rising costsSource: BBC News | Science & Environment | UK Edition | 8 Jul 2009 | 1:16 pm Nasa image of Arctic ice reveals 40% thinning since 2004Study - based on satellite measurements - among first to estimate the thickness of the Arctic ice, rather than surface area The Earth is going thin on top. A new study has revealed that the Arctic Ocean's permanent blanket of ice around the North Pole has thinned by more than 40% since 2004. Scientists said the rapid loss was "remarkable" and could force experts to reassess how quickly the Arctic ice in the summer may disappear completely. They blame the loss on global warming, which has driven temperatures in the Arctic to record highs and summer ice extent to recent lows. The study, based on satellite measurements, is among the first to estimate the thickness of the Arctic ice, rather than just its surface area. Ron Kwok, senior research scientist at Nasa's Jet Propulsion Laboratory in California, said: "Even in years when the overall extent of sea ice remains stable or grows slightly, the thickness and volume of the ice cover is continuing to decline, making the ice more vulnerable to continued shrinkage." The study looked at measurements taken of the Arctic region by the Icesat satellite, launched in 2003. Overall, the experts found that the ice, typically up to about 3m thick, thinned by 67cm over the last four winters. Converting to ice volume, the scientists worked out the amount of so-called multiyear ice, which persists through Arctic summers, had decreased in the winter by up to 6,300 cubic kilometres since 2005 – a decline of more than 40%. The research is published in the Journal of Geophysical Research: Oceans. Kwok said: "Ice volume allows us to calculate annual ice production and gives us an inventory of the fresh water and total ice mass stored in Arctic sea ice. Our data will help scientists better understand how fast the volume of Arctic ice is decreasing and how soon we might see a nearly ice-free Arctic in summer." Earlier this year, scientists warned that sea ice volume reached a record low in 2008 due to an unusually high proportion of the thinner first year ice. Donghui Yi, a scientist with Nasa's Goddard Space Flight Centre in Maryland who worked on the study, said: "The main reason [for the ice thinning] is the growth in melting of the multiyear ice, which is caused by the warmer weather. More ice melts in summer and then you get less in winter." The Arctic ice cap fluctuates with the seasons, growing in the freezing winter and shrinking over the summer. An important finding of the study is that the majority of Arctic ice no longer survives the summer. In 2003, this multiyear ice made up 62% of the region's total ice volume. By 2008, this was down to 32%. The remaining 68% was "first-year" seasonal ice, which was open water during the summer, so is thinner and more likely to melt away. Yi said it would be dangerous to try to use the results to predict when the Arctic might be ice-free in summer. "Some people might do that but I wouldn't like to do those kinds of linear predictions." More years of data are needed to make an informed judgement, he said. Unfortunately, the Icesat's data gathering days are nearly over. Two of its three lasers, used to judge the sea ice height, have already failed and the third is on its last legs. Icesat2, the satellite's replacement, is not planned for launch until 2014. guardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds
Source: Science news, comment and analysis | guardian.co.uk | 8 Jul 2009 | 12:33 pm BLOG: Skies Darken Over IraqA satellite image shows a massive dust storm covering the nation of Iraq.Source: Discovery News Top Stories : Discovery Channel | 8 Jul 2009 | 11:40 am U.S.-Mexico Border Fence May Snag WildlifeThe fence threatens already limited populations of pygmy owls and bighorn sheep.Source: Discovery News Top Stories : Discovery Channel | 8 Jul 2009 | 11:15 am Striking salamander species foundA new species of lungless salamander is discovered, the most distinct amphibian found in the US for nearly 50 years.Source: BBC News | Science & Environment | UK Edition | 8 Jul 2009 | 11:01 am GM as a tool in struggle against povertyWe need more, and perhaps different, strategies to give farmers on low-quality soils a better chance at improving their lot Salty soils affect the growth of plants worldwide, particularly in irrigated land where one-third of the world's food is produced. It is estimated that one-fifth of irrigated land is salt-affected. And it is a problem that is only going to get worse as pressure to use more water increases and the quality of water decreases. Helping plants to withstand this salty onslaught would have a significant impact on world food production. Salt in the soil also affects dryland agriculture, particularly in semi-arid regions of the world, such as in the Middle East, Kazakhstan and Australia. 70% of Australia's wheat crop is affected by salt that is found as much a metre beneath the surface – this is important, as Australia is one of the world's largest exporters of wheat. Any approaches which can be taken to reduce the impact of salinity on world food production would be valuable. The world food situation is now critical. More than one billion people now go hungry each day. World grain stores are now lower than they have been for fifty years, since before the Green Revolution. Reflecting this, prices have increased greatly. Pressures from increasing population, increasing standards of living and biofuels, all in the context of global climate change, are making demands that are increasingly difficult to meet. The inequitable distribution of food is, of course, very important, as are problems of distribution of better seed varieties and basic farming technologies to farmers. These are perennial issues which intergovernmental organisations (such as the Consultative Group on International Agricultural Research) and charities (eg the Rockefeller Foundation) have battled valiantly to address for decades. And support for this must continue. But despite such wonderful work and many local victories, the problems globally are getting worse, not better. We need more and, perhaps, different strategies – including new technologies. In my group's research over the past ten years, we have been studying the mechanisms plants use to tolerate salinity, and how to manipulate these processes so that plants can keep growing while the salt keeps rising. We have generated plants that are much more tolerant to salt, work which was published yesterday. One mechanism of salinity tolerance involves keeping the toxic sodium ion (Na+) out of the leaves. One way to do this is to reduce the amount of Na+ moving from the roots to the shoots in the stream of water that flows up through the plant's water conducting pipes. We made a targeted genetic tweak so that Na+ is removed from the water flowing up the stem before it reaches the shoot – once out, it is stuck. The effect of this manipulation is to reduce the amount of toxic Na+ building up the shoot and so increase the plant's tolerance to salinity. The control of the gene we manipulated is crucial. To be effective, it must be tuned up so that it works harder and produces more protein than it usually would specifically around the plant's water conducting tubes in the mature root. In doing this, we have enhanced a process used naturally by plants to minimise the movement of Na+ to the shoot. We have used genetic modification (GM) to amplify the process, helping plants to do what they already do – but to do it much better! We are now in the process of transferring the technology to crops such as rice, wheat and barley. And results in rice already look very promising. The motivation for my research is as an independent academic seeking knowledge and its application for public good. It is driven by the same imperatives that led me to be an active member of the UK Green party for nearly a decade. As such, I consider my funding sources to be irrelevant to my academic integrity. Nevertheless, I can declare that none of our research on salinity has been paid for by industry. All funding has been from UK, EU or Australian governmental sources or from charities such as the Leverhulme Foundation. Furthermore, the outputs described in the paper are fully and freely available for public benefit. I hope very much that the principles of our work can be applied to develop salt-tolerant crops in developing countries and give farmers on low-quality soils a better chance at improving their lot. And giving people a chance to better their situation is something we need to facilitate, not impede. The west may not need more food, but remember Make Poverty History – a child dies unnecessarily as a result of extreme poverty every three seconds. GM crops are not the answer to this shameful global situation, but I argue strongly that they provide another tool, another option to try to address the problem. And I do not think those of us sitting in comfortable wealth have a right to deny people the opportunity to improve their production of food. The technology is just that, a technology. Like nuclear technologies (radiotherapy or nuclear weapons) or mobile phones (communication or bomb triggers), how we use it is the main issue. I hope that the plants we have generated provide a subtle use of GM technology that will allow some positive benefits for the developing world. Prof Mark Tester started working on mechanisms of salinity tolerance at the University of Cambridge, and has continued this over the past five years at the Australian Centre for Plant Functional Genomics and the University of Adelaide in Australia. His research also includes increasing the efficiency of nitrogen in crops and the concentration of iron and zinc in rice grain – to address the world's biggest health problem, micronutrient deficiency. guardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds
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