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Link Between Widely Used Osteoporosis Drugs And Heart Problems ProbedNew research evaluated the link between a common class of drugs used to prevent bone fractures in osteoporosis patients and the development of irregular heartbeat.Source: ScienceDaily: Latest Science News | 13 Apr 2009 | 3:00 pm Prehistoric Bears Ate Everything And Anything, Just Like Modern CousinsBy comparing the craniodental morphology of modern bear species to that of two extinct species, researchers have discovered that the expired plantigrades were not so different from their current counterparts. The cave bear, regarded as the great herbivore of the carnivores, was actually more omnivorous than first thought. The short-faced bear, a hypercarnivore, also ate plants depending on their availability. The work offers key insights into the evolution of the carnivore niches during the Ice Age.Source: ScienceDaily: Latest Science News | 13 Apr 2009 | 3:00 pm Public Trust Doctrine Could Aid Management Of U.S. Ocean WatersSince Congress lifted a moratorium on offshore drilling last year, federal lawmakers have grappled with the issue of how best to regulate US ocean waters to allow oil, wave and wind energy development, while sustainably managing critical fisheries and marine animal habitats.Source: ScienceDaily: Latest Science News | 13 Apr 2009 | 3:00 pm Pig Of The Future Might Be Free Of Diseases That Can Infect PeoplePigs are known carriers of the bacterium Yersinia enterocolitica, and they can infect both other pigs and people. Human infection occurs through eating improperly-cooked pork. Scientists are trying to rid pigs of the bacterium.Source: ScienceDaily: Latest Science News | 13 Apr 2009 | 3:00 pm Frogs Reveal Clues About The Effects Of Alcohol During DevelopmentAlcohol can cause severe birth defects characteristic of fetal alcohol spectrum disorder or fetal alcohol syndrome, but why these abnormalities occur is remains a mystery. Researchers have used frog embryos to show that alcohol steals away molecules needed for normal development and uses them for its own detoxification, causing cellular disorientation during a critical period of growth.Source: ScienceDaily: Latest Science News | 13 Apr 2009 | 3:00 pm Bioterrorism: Fast And Sensitive Way To Detect RicinScientists have developed a simple, accurate, and highly sensitive test to detect and quantify ricin, an extremely potent toxin with potential use as a bioterrorism agent.Source: ScienceDaily: Latest Science News | 13 Apr 2009 | 3:00 pm Fat-derived Inflammatory Factor May Explain Diseases That Come With ObesityAn inflammatory factor already linked to several diseases, including pulmonary disease, lung cancer, and arthritis, may also be responsible for the insulin resistance that comes with obesity, according to a new study.Source: ScienceDaily: Latest Science News | 13 Apr 2009 | 12:00 pm Epigenetics: DNA Isn’t EverythingResearch into epigenetics has shown that environmental factors affect characteristics of organisms. These changes are sometimes passed on to the offspring. Does this in any way oppose Darwin's theory of evolution? Not according to researchers.Source: ScienceDaily: Latest Science News | 13 Apr 2009 | 12:00 pm Scientists Show How A Neuron Gets Its ShapeFor the brain to work, neurons have to be connected in the right places. Now, new research shows that rather than growing like the branches of a tree -- extending outward -- certain neurons work backward from their destination, dropping anchor and stretching their dendrites behind them as they crawl away.Source: ScienceDaily: Latest Science News | 13 Apr 2009 | 12:00 pm Diseased Cartilage Harbors Unique Migratory Progenitor CellsA new study finds previously unidentified fibrocartilage-forming progenitor cells in degenerating, diseased human cartilage, but not in cartilage from healthy joints. The research provides valuable insights into the reparative potential of cartilage and may lead to development of regenerative therapies for arthritis.Source: ScienceDaily: Latest Science News | 13 Apr 2009 | 12:00 pm Japan's Antarctic whale catch short (AFP)
Source: Yahoo! News: Science News | 13 Apr 2009 | 10:32 am Catholic Democrats: Is Their Support for Obama Fraying? (Time.com)Time.com - Catholics who supported the President expected him to reverse policies on abortion funding and stem-cell research. But they're starting to feel their voices aren't being heardSource: Yahoo! News: Science News | 13 Apr 2009 | 6:50 am Attenborough warns on populationThe film-maker Sir David Attenborough becomes a patron of a group seeking to cut the growth in human population.Source: BBC News | Science & Environment | UK Edition | 13 Apr 2009 | 1:39 am Next-Gen Atom Smashers: Smaller, Cheaper and Super Powerful
Size matters in particle physics: The bigger the machine, the more violently physicists can smash atoms together and break open the deepest mysteries of the subatomic world. But a revolutionary new technology could eventually render some gargantuan particle accelerators passé. Using simulations, a team of German and Russian physicists have pioneered a new technique for particle acceleration, called proton-driven plasma-wakefield acceleration (PWFA). The technique may one day allow machines a fraction of the size of today's accelerators to create the highest-energy particles ever. "This could be a major step forward," says Allen Caldwell of the Max Planck Institute for Physics in Munich, coauthor of the study, which appeared in Nature Physics Sunday. "The dream is that it will lead to much more compact — and therefore much cheaper — electron accelerators." Progress in particle physics is contingent on the power of particle accelerators, and as particle colliders grow, the price tag and bureaucratic hurdles grow with them. Government pocketbooks are becoming increasingly tight -- in December both the U.S. and the U.K. pulled out of the proposed $7-billion International Linear Collider, which may never actually be built. So in order to continue searching for answers to physics' greatest questions — dark matter, extra dimensions, supersymmetry — physicists may have to find a fundamentally new way to accelerate particles. Caldwell and his colleagues hope proton-driven PWFA will pave the way. Giant particle accelerators work by smashing subatomic particles such as electrons or protons together at high energies. This transforms the particles into energy, which then converts back into matter, potentially revealing new particles and advancing understanding of old ones. Over the past half century, particle accelerators have thoroughly probed the lower energy levels. The next frontier is the land of the teraelectronvolt (TeV, or a million million electronvolts). There are only two ways for accelerators to increase the power: create a stronger electric field, or increase the distance over which particles are accelerated. We've already pretty much maxed out the strength of electric fields that can be contained without ripping electrons off the walls and essentially melting the inside of the accelerator. The other option is to create ever larger accelerators. Building bigger proton accelerators, such as Fermilab's Tevatron in Illinois and the Large Hadron Collider in Europe, is still possible because protons can be accelerated to very high energies in a circle. But the highest-energy electrons need linear tracks such as that of the SLAC National Accelerator Laboratory or the proposed International Linear Collider. While proton accelerators are more powerful because of the continuous circular acceleration, electron accelerators are important because they are more precise. This is where plasma-wakefield acceleration may be able to help. This radically new kind of acceleration skirts the electric field issue by using plasma — gas in which electrons have been ripped from their nuclei. This soup of ionized gas can handle electric fields about a thousand times stronger than can conventional accelerators, meaning the accelerators can potentially be a thousand times shorter.
But as the electrons snap back toward the bubble, they overshoot their original positions. So the particle bullet leaves behind a wake of mispositioned electrons, creating an intense electric field. By riding in this wake, the electrons can reach very high energies in a very short distance. In 2007, a collaboration between SLAC, UCLA, and USC demonstrated PWFA's potential: In a single meter, they were able to boost electrons zooming down SLAC's linear track to twice what they can achieve over the entire two-mile-long accelerator. But this strategy also has its limits. The maximum energy of the accelerated electrons depends on the energy of the particle bunches. SLAC currently produces the highest-energy electrons of any accelerator, at 50 gigaelectronvolts (GeV, or a thousand million electronvolts). So Caldwell and his colleagues decided to give plasma-wakefield acceleration a new twist by blasting the plasma with protons instead of electrons. Today's accelerators can bring protons to much higher energies than they can electrons. Protons at the Tevatron can hit 1 TeV (hence the name), and those at the LHC will be seven times as energetic. "This would be a tool to transfer that energy from the protons to the electrons, via the plasma, in a single stage," says Caldwell. In a numerical simulation, the team used proton-driven PWFA to accelerate electron bunches to 500 GeV in 300 meters of plasma. Compare that to the proposed $7 billion International Linear Collider (ILC), which will need at least nine miles to hit the same target, and SLAC's linear accelerator, which needed 10 times the distance to reach a tenth of the energy. Combining the new proton-driven PWFA with the LHC's powerful proton beam, Caldwell says it might be possible to accelerate electrons to several TeV, so that physicists can have their power, and their precision too. "I look forward to watching these ideas continue to develop," says Mark Hogan, a member of the electron-driven PWFA team at SLAC. "There is still a lot of research and development needed to nurture these ideas. But in the not too distant future, we may find that ideas such as this have transformed the field of particle accelerators to make future machines that are both smaller and more affordable to society." Electron acceleration by proton-driven PWFA is in its earliest theoretical stages — this study is the first to describe the concept — and is far from experimental verification. Perhaps the biggest issue is the proton bunch length, which must be very small to allow the electrons to overshoot and create the wakefield. "It's easy to do for electron bunches," says co-author Frank Simon of the Max Planck Institute. "But hadron colliders have bunches that are centimeters in length. We need bunches that are a hundred micrometers in length. We're still looking at how to test the idea with present technology." As governments put a stranglehold on spending, advancements in PWFA may be the best hope for refining the discoveries expected to be made at the LHC. "In the past, opening up energy frontiers allowed us to discover new particles and to understand the basic forces," says Caldwell. "Today, there are new theories around that we want to test which predict new particles. But the basic reason is to just see what's there." Citation: "Proton-driven plasma-wakefield acceleration" by Allen Caldwell, Konstantin Lotov, Alexander Pukhov, and Frank Simon. Nature Physics, April 12. See Also:
Images: Laser-wakefield acceleration visualization / Lawrence Berkeley National Laboratory. Source: Wired: Wired Science | 13 Apr 2009 | 1:37 am Science Weekly: Christopher Potter's history of the universeOur guest this week is Christopher Potter. A former mathematician, he went on to commission and edit some of the most popular science books of the past few decades, including Dava Sobel's Longitude and Fermat's Last Theorem by our own columnist Simon Singh. He has also worked on fiction by celebrated novelists Annie Proulx and Carol Shields. His latest book – this one penned by himself – is called You Are Here – A Portable History of The Universe. Alok Jha asks him why he decided to embark on this cosmically ambitious writing project. In the Newsjam we discuss how big business suddenly seems to be getting concerned about the environment and why Nasa is feeling headless, and Alok describes how he became a botanical Indiana Jones for two days when he joined a Kew Gardens expedition hunting for some very rare seeds. Check out our gallery of extraordinary, alien seed and pollen images that are part of Kew's 250th anniversary celebrations. Finally, Ian Sample looks at the words that have crossed over from science fiction into real life. "Robotics" and "zero-g" were all in print before they were used by scientists, and the team suggest a few more words that could make the leap. Leave your comments on the blog below, on our Facebook wall, or Tweet us. We really appreciated your feedback, and read out the best comments in the programme. • Comment below ... Source: Evolution, genetics, medicine, physics & astronomy news | guardian.co.uk | 12 Apr 2009 | 11:05 pm Scientists find 'pleasure nerves'Scientists in the US and Sweden say they understand more about how the body responds to pleasurable touch.Source: BBC News | Science & Environment | UK Edition | 12 Apr 2009 | 11:02 pm Obituary: Margaret PerryA molecular geneticist whose research helped to produce a chick without its own egg shell My cousin Margaret Perry, who has died aged 78, was a molecular geneticist and embryology researcher, who, in 1988, inserted foreign genetic material into one-cell chicken embryos and cultured them to hatching. Soon the New York Times was alerting its readers to news that Margaret had "learned how to produce the chick without its own egg shell". The New Scientist pointed out this was the first time that any warm-blooded animal had developed completely in vitro. Margaret's chickens were born at the Roslin Institute, in Edinburgh, where, nine years later, Dolly the Sheep would be born. Margaret was extraordinarily modest, remarking that she often saw people's eyes glaze over when answering the question of what work she did. So she rarely spoke of it. Her father was a civil engineer and her mother was among that early generation of women graduates (Manchester University, 1923). Margaret was born in Stockton-on-Tees and educated at St Joseph's college in Bradford, where a pioneering headmistress developed a science laboratory. She graduated in zoology and genetics from Edinburgh University in the mid-1950s, and settled in the city for the rest of her life. She studied the embryology of amphibians at the university genetics department before moving into poultry research at the Roslin. Feted internationally, she spoke at conferences in Poland and Japan and worked in France on electron microscope techniques. She was a great traveller, and, after retiring 18 years ago, visited Nepal, Australia, Egypt and the Galápagos Islands. She indulged her love of walking in the Highlands and Islands and made many friends in the Natural History Society of Edinburgh. A lifelong Guardian reader, and a lover of food and wine, she would offer carefully crafted gin and tonics as pre-dinner snifters. As quiet a Catholic as she was a scientist, Margaret clearly reconciled her faith and genetic work. It was only after her death that we discovered that for many years she had made weekly visits to the Royal Edinburgh hospital, helping the longer-term patients to mass. She ministered communion at the Astley Ainslie hospital and was a member of the St Vincent de Paul Society at her Morningside church. Shortly before she died, asked for a hospital radio request, she chose Schubert's The Trout. On my mother's funeral flowers, Margaret, quoting Thomas More, wrote: "May we meet merrily in heaven." I hope they have. She is survived by her sister Maureen, cousins, nephews and nieces. guardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds
Source: Evolution, genetics, medicine, physics & astronomy news | guardian.co.uk | 12 Apr 2009 | 11:01 pm StarwatchAs part of the Hubble Space Telescope's contribution to the International Year of Astronomy, and as a result of a public vote to choose a suitably photogenic subject, an image of two spiral galaxies and their smaller neighbour was obtained just a couple of weeks ago. The galaxy group is called Arp 274 after the US astronomer Halton Arp who catalogued hundreds of extragalactic oddities, many of them galaxies that appeared to be interacting gravitationally or even merging together. Arp is a controversial exponent of the theory that some of the redshifts of galaxies and quasars may have a local cause rather than be due, as most believe, to the universal expansion since the Big Bang. Most astronomers, though, place Arp 274 some 400 million light years away. At that distance, the image, with north to the left, spans a region about 200,000 light years from top to bottom, twice the diameter of our own Milky Way. The brightest of the two foreground stars near the centre-top of the image is of the twelfth magnitude while the galaxies themselves are fainter still and very difficult to see through normal amateur-owned telescopes. In fact, the redshift evidence suggests that the middle galaxy lies perhaps 60 million km beyond the other two, and it is by no means certain that the three are interacting gravitationally after all. The galaxies lie in eastern Virgo, 15° below Arcturus in Bootes which is the brightest star climbing through our eastern sky this evening. The central bulges of the upper two galaxies are coloured by older and redder stars, ones that formed early in the life of the galaxy when the star-forming material was relatively devoid of elements heavier than the hydrogen and helium created in the Big Bang. Such stars may have few planets. As the galaxies aged, the interstellar gas became enriched with the heavier elements that are "cooked" within stars and ejected near the end of their lives. Young bluish stars formed from this now-dusty material illuminate the spiral arms and energise the pink knots of glowing clouds of hydrogen sprinkled along them. The small lower galaxy is particularly bluish and may be enjoying a burst of star-formation, possibly because its material has compressed gravitationally during a recent approach to one of its neighbours. guardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds
Source: Evolution, genetics, medicine, physics & astronomy news | guardian.co.uk | 12 Apr 2009 | 11:01 pm WITNESS: "Hi, is that the Somali pirates?" (Reuters)Reuters - Your best source is jailed. You track high-sea hijacks by text and email. You get through to captors on a satellite phone but are then roundly abused.Source: Yahoo! News: Science News | 12 Apr 2009 | 7:48 pm Mobile technology battles HIVOn the edge of Uganda's Impenetrable Forest, a team offers state of the art medical care for HIV positive patients.Source: BBC News | Science & Environment | UK Edition | 12 Apr 2009 | 6:00 pm Fertility: Scientists in China transform stem cells into eggsExperts caution that Shanghai team's findings are tentative and need confirmation Infertile women may one day be given stem cell injections to repopulate their ovaries with fresh eggs, according to a team of scientists. Hopes for the new therapy follow experiments in which sterilised mice produced eggs and went on to give birth to healthy young after adult females had stem cells injected into their ovaries. If the procedure can be made to work in humans, it could lead to treatments that extend fertility beyond the menopause and help younger women who are unable to conceive because their eggs have been damaged by cancer therapies or disease. The controversial research challenges the long-held belief that most female mammals are born with a fixed number of eggs and are unable to make more throughout their lives. The study, which appears in the journal Nature Cell Biology, was received with caution, with some experts emphasising that the findings are tentative and need to be confirmed by other researchers. In the study, scientists led by Ji Wu at Shanghai Jiao Tong University extracted what they believe to be stem cells from the ovaries of adult and five-day-old mice. These were grown into a large stock of cells, which the researchers call female germline stem cells (FGSCs). Germline cells are the only cells in the body that grow into sperm or eggs. While sperm-making stem cells have been found in male testes, no one has ever found incontrovertible evidence for similar cells that make eggs in ovaries. To test whether the extracted cells could make eggs, the researchers sterilised a group of female mice using busulphan, a chemotherapy drug. They then injected 10,000 stem cells into both ovaries of each mouse. The cells had been frozen and thawed out before being used, to simulate the conditions they would be kept in if stored for human patients. A few months after leaving the mice to mate naturally, 18 out of 22 that received stem cell transplants from newborn mice gave birth to pups. A further 12 out of 15 females injected with stem cells from adult mice also gave birth. All of the offspring appeared to be healthy. In their journal report, the team write that the work suggests eggs "can be regenerated in sterile recipient females by transplantation of FGSCs". If scientists can find stem cells in women's ovaries, the Shanghai team's study shows it might be possible to use them to create stocks of cells for women, which could be stored in a deep freeze until they are needed. "This paper will stimulate lots of activity in the scientific community, as happens when any dogma is challenged," said Robin Lovell-Badge, a researcher into stem cells at the MRC National Institute For Medical Research in London. "But what would be unfortunate is if this paper is hyped as a cure for female infertility. A lot more work is needed to understand what these new cells really are, and to verify the findings and the claims," he added. Lovell-Badge points out that some of the mice may not have been completely sterilised before being treated, making it impossible to know whether their offspring came from surviving or regenerated eggs. "If true, and especially if applicable also to humans, then this is very important. It could provide a means to restore fertility to women who have few eggs or who have had to undergo cancer treatments," he added. guardian.co.uk © Guardian News & Media Limited 2009 | Use of this content is subject to our Terms & Conditions | More Feeds
Source: Evolution, genetics, medicine, physics & astronomy news | guardian.co.uk | 12 Apr 2009 | 5:50 pm Arctic diaryExplorers share their wilderness with othersSource: BBC News | Science & Environment | UK Edition | 12 Apr 2009 | 4:39 pm New rare orangutan find in BorneoA group of about 1-2,000 orangutans has been discovered on the south-east Asian island of Borneo.Source: BBC News | Science & Environment | UK Edition | 12 Apr 2009 | 4:31 pm Galapagos volcano erupts, could threaten wildlife (AP)
Source: Yahoo! News: Science News | 12 Apr 2009 | 12:25 pm New orangutan population found in Indonesia (AP)
Source: Yahoo! News: Science News | 12 Apr 2009 | 12:09 pm
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