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Beverages leave 'geographic signatures' that can track people's movementsThe bottled water, soda pop or micro brew-beer that you drank in Pittsburgh, Dallas, Denver or 30 other American cities contains a natural chemical imprint related to geographic location. When you consume these beverage you may leave a chemical imprint in your hair that could be used to track your travels over time, a new study suggests.Source: ScienceDaily: Latest Science News | 1 Jul 2010 | 12:00 pm Complex, multicellular life from over two billion years ago discoveredThe discovery in Gabon of more than 250 fossils in an excellent state of conservation has provided proof, for the first time, of the existence of multicellular organisms 2.1 billion years ago. This finding represents a major breakthrough: until now, the first complex life forms (made up of several cells) dated from around 600 million years ago. These new fossils, of various shapes and sizes, imply that the origin of organized life is a lot older than is generally admitted, thus challenging current knowledge on the beginning of life.Source: ScienceDaily: Latest Science News | 1 Jul 2010 | 12:00 pm Better way to battle mosquitoes: Research could provide more effective treatment against West Nile VirusA Canadian study has found that rather than cleaning and treating catch basins in the spring with S-methoprene to control mosquitoes, authorities should clean catch basins in the fall, allow organic debris to accumulate, and then treat catch basins with S-methoprene in the spring. This method dramatically reduces the number of mosquitoes that make it to the adult stage and may have implications for West Nile virus.Source: ScienceDaily: Latest Science News | 1 Jul 2010 | 12:00 pm Apples grow larger when cells don't divide, study showsHorticultural experts found that an anomaly in some Gala apple trees causes some apples to grow much larger than others because cells aren't splitting. The findings showed that the new variety, called Grand Gala, is about 38 percent heavier and has a diameter 15 percent larger than regular Galas.Source: ScienceDaily: Latest Science News | 1 Jul 2010 | 12:00 pm Exposure to secondhand smoke in the womb has lifelong impact, study findsNewborns of nonsmoking moms exposed to secondhand smoke during pregnancy have genetic mutations that may affect long-term health, according to a new study. The abnormalities, which were indistinguishable from those found in newborns of mothers who were active smokers, may affect survival, birth weight and lifelong susceptibility to diseases like cancer.Source: ScienceDaily: Latest Science News | 1 Jul 2010 | 12:00 pm Some males react to competition like bonobos, others like chimpanzeesThe average man experiences hormone changes similar to the passive bonobo prior to competition, but a "status-striving" man undergoes changes that mirror those found in a chimpanzee, say researchers.Source: ScienceDaily: Latest Science News | 1 Jul 2010 | 12:00 pm 'Butterfly effect' in the brain makes the brain intrinsically unreliableNext time your brain plays tricks on you, you have an excuse: according to new research, the brain is intrinsically unreliable.Source: ScienceDaily: Latest Science News | 1 Jul 2010 | 9:00 am New technique improves efficiency of biofuel productionResearchers have developed a more efficient technique for producing biofuels from woody plants that significantly reduces the waste that results from conventional biofuel production techniques. The technique is a significant step toward creating a commercially viable new source of biofuels.Source: ScienceDaily: Latest Science News | 1 Jul 2010 | 9:00 am Melanoma-initiating cell identifiedScientists have identified a cancer-initiating cell in human melanomas. The finding is significant because the existence of such a cell in the aggressive skin cancer has been a source of debate. It may also explain why current immunotherapies are largely unsuccessful in preventing disease recurrence in human patients.Source: ScienceDaily: Latest Science News | 1 Jul 2010 | 9:00 am Ovarian transplantation restores fertility to old mice and also lengthens their livesScientists have discovered that when they transplant ovaries from young mice into aging female mice, not only does the procedure make the mice fertile again, but also it rejuvenates their behavior and increases their lifespan.Source: ScienceDaily: Latest Science News | 1 Jul 2010 | 9:00 am 'Cookies' point to complex lifeScientists report the discovery of centimetre-sized fossils that may be the earliest known examples of multicellular life.Source: BBC News | Science & Environment | UK Edition | 1 Jul 2010 | 4:11 am Turtle egg rescue plan announcedScientists announce plans to protect sea turtle nests and eggs from potential impacts of the oil spill in the Gulf of Mexico.Source: BBC News | Science & Environment | UK Edition | 1 Jul 2010 | 3:55 am 'Robofish' accepted by wild fishScientists create a remote controlled "robofish" that sticklebacks accept as one of their own.Source: BBC News | Science & Environment | UK Edition | 1 Jul 2010 | 3:54 am Three-legged dogs aid robot studyScientists have filmed and studied three-legged dogs walking on treadmills in a bid to develop robot-building strategies.Source: BBC News | Science & Environment | UK Edition | 1 Jul 2010 | 3:26 am BP spill nears a somber record as Gulf's biggest (AP)
Source: Yahoo! News: Science News | 1 Jul 2010 | 3:06 am Premature pupsFishing's history makes seals give birth earlierSource: BBC News | Science & Environment | UK Edition | 1 Jul 2010 | 3:04 am Faster clean-up mooted for Wales nukesDecommissioning work at Trawsfynydd's nuclear power station could be speeded up if plans are approved the UK government.Source: BBC News | Science & Environment | UK Edition | 1 Jul 2010 | 3:04 am The nation's weather (AP)
Source: Yahoo! News: Science News | 1 Jul 2010 | 3:03 am Scientists seek 20,000 Labrador retrievers for lifestyle studyScientists in Edinburgh launch a search for 20,000 Labrador retrievers to help them understand dog lifestyles.Source: BBC News | Science & Environment | UK Edition | 1 Jul 2010 | 2:31 am Indonesia's last glacier will melt within years (AP)
Source: Yahoo! News: Science News | 1 Jul 2010 | 1:49 am 'Sex' drove fossil animal traitsSeveral prehistoric creatures developed elaborate body traits in order to attract members of the opposite sex, a study says.Source: BBC News | Science & Environment | UK Edition | 1 Jul 2010 | 1:45 am 'Sea monster' fossil unearthedResearchers have discovered the fossilised remains of a 12-million-year-old whale with huge, fearsome teeth.Source: BBC News | Science & Environment | UK Edition | 1 Jul 2010 | 1:44 am South Korean man charged over device that 'created holy water'A South Korean professor faces fraud charges for selling a digital device he said could convert tap water into holy water.Source: BBC News | Science & Environment | UK Edition | 1 Jul 2010 | 1:18 am NZ carbon price system hikes household costs (AP)AP - New carbon-trading laws intended to reduce climate-changing pollution emissions took effect Thursday in New Zealand, immediately sending gas prices higher.Source: Yahoo! News: Science News | 1 Jul 2010 | 1:02 am New Zealand launches emissions trading scheme (AFP)
Source: Yahoo! News: Science News | 1 Jul 2010 | 12:52 am Swiss team postpones solar plane night flight (AP)AP - A Swiss team planning to circle the globe in a solar-powered plane has postponed a 24-hour test flight because of an equipment problem.Source: Yahoo! News: Science News | 1 Jul 2010 | 12:25 am Air Force Launches Ballistic Missile In Suborbital Test (SPACE.com)SPACE.com - The United States Air Force launched an intercontinental ballistic missile (ICBM) on a test flight early Wednesday, sending the weapon on a suborbital trajectory that reached thousands of miles downrange over the Pacific Ocean.Source: Yahoo! News: Science News | 1 Jul 2010 | 12:15 am Hurricane Alex pounds Mexico but spares U.S. oil rigs (Reuters)
Source: Yahoo! News: Science News | 1 Jul 2010 | 12:01 am 'Not enough money' for all BP oil spill claims (AFP)
Source: Yahoo! News: Science News | 30 Jun 2010 | 11:55 pm BP oil spill cleanup work hampered by hurricane (Reuters)
Source: Yahoo! News: Science News | 30 Jun 2010 | 11:15 pm Ancient macrofossils unearthed in West AfricaTwo-billion-year-old fossils could indicate steps towards multicellularity.<img src="http://feeds.feedburner.com/~r/news/rss/today/~4/evqzLR6PC5c" height="1" width="1"/>Source: NatureNews - All articles published today - nature.com science feeds | 30 Jun 2010 | 4:47 pm Satellite spots soggy soilEuropean Space Agency mission provides the first global map of a key climate variable.Source: NatureNews - All articles published today - nature.com science feeds | 30 Jun 2010 | 4:43 pm Three-Legged Dogs Teach Robots New TricksAnalyzing how three-legged dogs run could help inventors design and develop robots that can adapt to injuries.Source: Livescience.com | 30 Jun 2010 | 4:10 pm Ostrich Wings Explain Mystery of Flightless DinosaursWings may not be evolutionary leftovers from when birds adapted for life on the ground.Source: Livescience.com | 30 Jun 2010 | 4:08 pm Acts of God: Why Lightning Strikes Religious SymbolsSome modern religious leaders believe that Acts of God (a legal, not theological, term) are divine retribution for mankind's wickedness and immorality.Source: Livescience.com | 30 Jun 2010 | 3:56 pm New Smell Drives Evolution of New Moth Species
A new scent is enough to spark the evolution of a new moth species — and it can start with just a single genetic mutation. Since the 1970’s, scientists have known that European corn borer moths are split between two groups. Each has a different molecular configuration of ECB, a pheromone emitted by females to attract males. The different groups are biologically capable of interbreeding — in captivity, given no other choices, they do — but in the wild, they stick to their kind. This sort of division is called reproductive isolation, and it’s an early step in the separation of one species into two. And while the importance of pheromonal differences to moths is understood, the underlying genetic mechanisms were not known. In a paper published in the July 1 Nature, Max Planck Institute geneticists cross-bred captive representatives of the two corn-borer groups. By comparing the gene profiles of offspring to parents, they were able to trace the pheromonal differences back to changes in the DNA sequence of a single gene called pgFAR. Exactly why such small changes should make the corn borers so picky is a mystery, but they clearly do.
“This is the first functional characterization of a gene” that produces reproductive isolation in moths, wrote the researchers. Moreover, a scan of other insect genomes showed pgFAR to be present only in Lepidoptera, the insect order containing moths and butterflies. Mutations to pgFAR have helped “generate the great diversity of pheromones used in moths, permitting the coexistence of thousands of species,” they wrote. The findings could help design synthetic pheromones for use in disrupting breeding in corn borers, which outside the world of evolutionary biology are a common farm pest. Of course, with speciation so easily stimulated, such schemes may well lead to the evolution of new species. Image: Corn borers mating./Jean-Marc Lassance. Citation: “Allelic variation in a fatty-acyl reductase gene causes divergence in moth sex pheromones.” By Jean-Marc Lassance, Astrid T. Groot, Marjorie A. Lienard, Binu Antony, Christin Borgwardt, Fredrik Andersson, Erik Hedenstrom, David G. Heckel & Christer Lofstedt. Nature, Vol. 466, No. 7302, July 1, 2010. Brandon Keim’s Twitter stream and reportorial outtakes; Wired Science on Twitter. Brandon is currently working on a book about ecological tipping points. See Also:
Source: Wired: Wired Science | 30 Jun 2010 | 3:42 pm Organic farms win at potato pest controlWhy ecological evenness is as important as relative richness.Source: NatureNews - All articles published today - nature.com science feeds | 30 Jun 2010 | 3:03 pm Climate science: An erosion of trust?Many climate researchers worry that scepticism about global warming is on the rise. Jeff Tollefson investigates the basis for that concern and what scientists are doing about it.Source: NatureNews - All articles published today - nature.com science feeds | 30 Jun 2010 | 3:00 pm Profile: The field medicWhen emergencies happen in remote settings, field researchers can be left with little recourse. Erik Vance meets a man trying to change that.Source: NatureNews - All articles published today - nature.com science feeds | 30 Jun 2010 | 3:00 pm Call meSperm whale fossil has the biggest whale bite ever seen.Source: NatureNews - All articles published today - nature.com science feeds | 30 Jun 2010 | 3:00 pm Entertaining scienceEfforts by the US National Academy of Sciences to popularize science through movies will sanitize it as well, says Daniel Sarewitz.Source: NatureNews - All articles published today - nature.com science feeds | 30 Jun 2010 | 3:00 pm CorrectionSource: NatureNews - All articles published today - nature.com science feeds | 30 Jun 2010 | 3:00 pm Robots Vie for Soccer GloryForget South Africa. The future of the World Cup is happening in Singapore.Source: Discovery News - Top Stories | 30 Jun 2010 | 2:15 pm Gross! Smelly Corpse Flower BloomsRare rotten-flesh-smelling flower opens.Source: Livescience.com | 30 Jun 2010 | 2:03 pm Dinosaurs Nestled Up to Geysers, Hot Springs to Incubate EggsDinosaurs that were attracted to the heat and moisture from hydrothermal vents for nesting may have been among the largest ever.Source: Discovery News - Top Stories | 30 Jun 2010 | 1:54 pm 2-Billion-Year-Old Fossils May Be Earliest Known Multicellular Life
A newly discovered group of 2.1-billion-year-old fossil organisms may be the earliest known example of complex life on Earth. They could help scientists understand not just when higher life forms evolved, but why. The fossils — flat discs almost 5 inches across, with scalloped edges and radial slits — were either complex colonies of single-celled organisms, or early animals. Either way, they represent an early crossing of a critical evolutionary threshold, and suggest that the crossing was made necessary by radical changes in Earth’s atmosphere. “There is clearly a relationship between the concentration of oxygen and multicellularity,” said Abderrazak El Albani, a paleobiologist at France’s University of Poitiers. The fossils are described in the July 1 issue of Nature. Single-celled organisms emerged from the primordial soup about 3.4 billion years ago. Almost immediately, some gathered in mats. But it was another 1.4 billion years before the first truly multicellular organism, called Grypania spiralis, appears in the fossil record. Grypania may have been either a bacterial colony or a eukaryote — an organism with specialized cells, enclosed in a membrane. Whatever Grypania was, it was one of the few known examples of complex life until about 550 million years ago, when the fossil record explodes in diversity.
Just a few million years before Grypania and the newly discovered fossils appear in the fossil record, Earth experienced what’s called the Great Oxidation Event. The sudden evolution of photosynthesizing bacteria radically changed Earth’s atmosphere, kick-starting its transformation from nearly oxygen-free into today’s breathable air. “The bacterial world was undergoing the greatest episode of climate change in the history of the climate,” wrote University of Bristol paleobiologists Phil Donoghue and Jonathan Antcliffe in a commentary accompanying the findings. “The proximity in the age of these fossils to the timing of the Great Oxidation Event fits elegantly” with the notion that changing ocean chemistry fueled the evolution of complex life. Bacteria possess chemical signaling systems, and many researchers now see their colonies — which can stretch for centimeters, numbering millions of individuals — as collective organisms, with different individuals having specialized body types and tasks. Growth patterns seen in the new fossils fit with those found in multicellular organisms capable of complex signaling and coordinated responses. Earth’s suddenly fluctuating climate would have favored communication. “When bacteria are under stress, it triggers their cooperation,” said biophysicist Eshel Ben-Jacob of Tel Aviv University. “Those that have to cope with a more complex environment show higher complexity.” “You have multicellular organization during the first upswelling of oyxgen in the atmosphere,” said El Abani. He said multicellular organisms likely evolved in many places, but the fossils haven’t yet been found. “All life on the earth had to change,” said Ben-Jacob. Images: 1) Virtual reconstruction of outer and inner structure of fossil specimen./Abderrazak El Albani and Arnaud Mazurier. 2) Fossil remains./Abderrazak El Albani. See Also:
Citations: “Large colonial organisms with coordinated growth in oxygenated environments 2.1 Gyr ago.” By Abderrazak El Albani, Stefan Bengtson, Donald E. Canfield, Andrey Bekker, Roberto Macchiarelli, Arnaud Mazurier, Emma U. Hammarlund, Philippe Boulvais, Jean-Jacques Dupuy, Claude Fontaine, Franz T.Fursich, Francois Gauthier-Lafaye, Philippe Janvier, Emmanuelle Javaux, Frantz Ossa Ossa, Anne-Catherine Pierso. Nature, Vol. 466, No. 7302, July 1, 2010. “Origins of Multicellularity.” By Philip Donoghue and Jonathan Antclifee. Nature, Vol. 466, No. 7302, July 1, 2010. Brandon Keim’s Twitter stream and reportorial outtakes; Wired Science on Twitter. Brandon is currently working on a book about ecological tipping points.
Source: Wired: Wired Science | 30 Jun 2010 | 1:24 pm Motorbikes Could Run Efficiently on AirMotorcycles powered by a compressed air engine could cut vehicular emissions in developing countries by more than half.Source: Livescience.com | 30 Jun 2010 | 1:08 pm World's Cutest Baby Wild AnimalsFrom baby porcupines to flamingo chicks, we've picked out the most adorable baby animals.Source: Livescience.com | 30 Jun 2010 | 12:37 pm Ancient Whale + Killer Shark = Hypercarnivorous Whale
What would you get if you crossed a whale with a shark? Maybe something like Leviathan melvillei, a long-extinct, hypercarnivorous whale with teeth longer than any T. rex ever had.
The longest of Leviathan’s teeth measure about 14 inches including the root, more than 40 percent longer than those of today’s sperm whales. And, Lambert notes, the longest tooth of Sue, one of the largest Tyrannosaurus rex specimens yet found, measures only 10.6 inches from root to tip.
Wear patterns indicate that Leviathan’s teeth sheared past each other during a bite, a sign that the beast could rip chunks of flesh from prey. Lambert and his colleagues speculate that Leviathan fed on medium-sized baleen whales, whose blubber would have been a rich source of calories.
Modern sperm whales feed largely on invertebrates such as giant squid, but have been known to feed on fish and other creatures as well. The extremely robust, deeply-rooted structure of Leviathan’s teeth strongly suggests that the creature fed on large, presumably struggling bony prey like sharks do. But that doesn’t mean the whale’s diet was restricted in any way. “If you’re big enough,” Fitzgerald notes, “you can bloody well eat what you want.” Images: 1) Artist’s rendering of the giant raptorial sperm whale Leviathan melvillei attacking a medium-size baleen whale off the coast of the area now occupied by Peru./C. Letenneur (MNHN). See Also:
Source: Wired: Wired Science | 30 Jun 2010 | 12:29 pm Rogue cells explain Parkinson's transplant problem: studyLONDON (Reuters) - Scientists working with Parkinson's disease patients who had pioneering transplant surgery using aborted foetal tissue have figured out what causes one of the most damaging side-effects of the treatment.Source: Reuters: Science News | 30 Jun 2010 | 12:15 pm Tunnel for Ancient Egyptian Ruler FoundThe 570-foot-long tunnel for Seti I was left unfinished and may have been designed to house a secret tomb.Source: Discovery News - Top Stories | 30 Jun 2010 | 12:14 pm What do astronauts want to be when they grow up?Astronauts are filling football stadiums and doing a great job starting children down the road to careers in science. What is it about them that still holds us spellbound, wonders Tom Whyntie You'd be hard-pressed to find a geeky science type who didn't want to be an astronaut when they were little. I'll admit it. I had the spacesuit and the space helmet. I even picked the smallest bedroom in our new house so that I could do it up like the international space station (something I seriously regretted as I got older). Of course when I encountered science in the classroom I realised that there was a lot more to it than rockets and satellites. In the end I went into particle physics, but space seems to have an allure that captures the imagination like nothing else. This perhaps goes some way towards explaining the scenes I witnessed in Portsmouth this week, when around 4000 schoolchildren from all over the south of England welcomed the crew of the Atlantis space shuttle to Fratton Park, home of Portsmouth FC. Sitting in the crowd listening to the cheers and adulation, I couldn't help thinking that the whole scene wasn't just very un-British, it was very un-scientific. You just don't get stadium audiences for science shows (well, Brian Cox hasn't yet). The astronauts' message was simple: they were "ordinary people doing extraordinary things". With hard work you could achieve anything, and science, engineering and "math" could lead to some particularly exciting careers. The aim of their post-mission European tour, of which Portsmouth was the first stop, was to take this message to as many young people as possible. Science and universities minister David Willetts, speaking at an event earlier in the day at Portsmouth Historic Dockyard, picked up on the same point. "There are two things that get kids into science – dinosaurs and space. Well, dinosaurs are the past, and space is the future." While I don't think that the Natural History Museum should be too concerned, one perhaps has to ask: why are astronauts given this hero status, and, given that we can't all be astronauts, is this a good way to promote science? The first question is easy. There is, of course, all the cool technology involved in getting into space. Then there's the bravery. At Fratton Park, I shook the hands of men who have regularly sat atop a tin can packed with jaw-dropping amounts of high explosive. These men have experienced the 7.5 million pounds of thrust provided by those explosives to get into orbit around our planet. They are men who, once safely inside their human-sized Rotastak, proceeded to "pop outside" to repair one of the greatest scientific instruments humankind has ever built, the Hubble space telescope. And at the end of each mission, they have weathered the fiery kiss of the Earth's atmosphere to land safely on their home planet. The courage required is phenomenal. I won't lie to you, I was unashamedly giggly. The second question is a little more tricky. What happens when the astronauts go home? What happens when the wide-eyed spacewoman-to-be realises that the UK Space Agency might not quite deliver HMSS Enterprise in time for her to embark on a space mission of her own? Well, this sort of misses the point. Once you get hooked on science – and space is a great hook - you just want to know more. And that follow-up is very much down to the unsung heroes of the piece, science teachers. That the astronaut visit to Portsmouth took place at all was down to Jeremy Thomas, a physics teacher from Portsmouth Grammar School who regularly organises trips for his students to Nasa through the International Space School Educational Trust. My "Mr Thomas" was Mr Flynn, who would always respond to my questions with a harder question that I'd gleefully try to tackle with my copy of Encarta '95 (we didn't have Wikipedia in those days). Sitting next to mission commander Ken Ham (pictured) at a dinner on HMS Warrior 1860, he recounted how one of his proudest moments was when, after a talk he gave at his home town, his "hard-ass" science teacher who had been in the audience tracked him down in a bar and joined him for a beer. It's the science teachers who will see students – potential scientists and future voters – every day. Ensuring that teachers have the support they need to do their job should be an intrinsic part of science's efforts to engender public understanding. The point hasn't been lost on the astronauts. We had broached the subject while discussing what was next for Commander Ham. What did this hero of science and engineering want to do now that his shuttle has landed for the last time? What did this astronaut want to be now that he'd "grown up"? Ken's answer was simple and given without hesitation. He wants to be a high school teacher. Tom Whyntie is a PhD student at Imperial College London, working on the Compact Muon Solenoid (CMS) experiment at Cern guardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds Source: Science news, comment and analysis | guardian.co.uk | 30 Jun 2010 | 12:00 pm News briefing: 25 June–1 July 2010The week in science.Source: NatureNews - All articles published today - nature.com science feeds | 30 Jun 2010 | 12:00 pm World’s Most Intense X-Ray Laser Takes First Shots
The world’s most intense X-ray laser may soon be the fastest strobe-light camera ever. Two of the laser’s first experiments show the device will be able to take snapshots of single molecules in motion — without destroying them first. The laser, called the Linac Coherent Light Source, takes up a third of the two-mile-long linear accelerator at the SLAC National Accelerator Lab in Menlo Park, California. In the accelerator hall, tight bunches of electrons wriggle through a series of magnets and give off X-rays billions of times brighter than earlier X-ray sources could muster. The wavelength of these X-rays is comparable to the radius of a hydrogen atom — about one angstrom, or one ten-billionth of a meter — and each pulse can be as short as a few quadrillionths of a second. These features make this kind of X-ray, called a hard X-ray for its ability to penetrate matter, an ideal scalpel to probe the inner workings of atoms and molecules. When the laser first flashed in April 2009, physicists dreamed of using it to make 3-D, time-lapse movies of atomic bonds breaking and proteins changing shape. Just like stop-motion photographs showed 19th-century photographers how horses run, the X-ray laser should show modern scientists how atoms interact. There’s just one potential problem: The X-rays will make the molecules explode. For imaging experiments to work, the laser’s shutter will have to be faster than its detonator.
In two of the first experiments, conducted last fall and reported in two recent papers, scientists put the laser through its paces to see if simple atoms and molecules can be photographed before they are destroyed. “Understanding how intense light, and in particular intense X-rays, interact with both atoms and molecules is critical to understanding how we’re going to be able to image systems using these intense light pulses in the future,” said laser physicist Roger Falcone of Lawrence Berkeley National Laboratory, a member of an advisory committee for the laser’s science team but was not involved in the new studies. In the first study, reported in the July 1 Nature, physicists blasted a neon atom with X-rays in a range of different energies. The researchers chose neon partially because it is in the second row of the periodic table, which also contains carbon, nitrogen and oxygen, the makeup of biological molecules. “If you can understand what’s going on in a second row element, you can understand how these [X-rays] will interact with biological molecules,” said physicist Linda Young of Argonne National Laboratory in Illinois, a co-author of the paper. Young and her colleagues tuned the laser to irradiate neon atoms with X-rays between 400 and 1,000 times more energetic than visible light. At energies below a certain threshold (870 electronvolts, or about 435 times more energy than is carried in a photon of visible light), X-rays knocked electrons off the neon atom’s outer electron shell like overenthusiastic billiard balls knocking each other off the pool table. But at higher energies, the innermost electrons were booted out first. This process left behind a hollow atom. This hollow atom doesn’t last very long before an electron from the outer shell drops down to fill the hole. And all the electrons peel off within one ten-trillionth of a second. “The neon atom is stripped bare naked within that short amount of time,” Young said. But the atom lasted long enough for Young and her colleagues to notice that, while it was hollow, the atom was more transparent to X-rays. That’s good news for future experiments to take images of atoms, Young said. X-rays can either be absorbed or scattered by an atom. But only the scattered X-rays are useful for making images, because they are the only ones that will end up on a detector at the end of the experiment. Hollow, transparent atoms let through more X-rays, which will make images easier to record. “To image single molecules and thereby reconstruct their structure, you need to be able to collect X-rays,” Young said. “We really established a framework for understanding the interaction of these X-rays with matter.” In the other experiment, published June 22 in Physical Review Letters, physicist Nora Berrah of Western Michigan University and colleagues turned the laser on a simple molecule, nitrogen gas. Instead of changing the energy of the X-rays, Berrah’s group changed the duration of the pulse. They bombarded the nitrogen molecules with X-ray pulses between 4 femtoseconds (quadrillionths of a second) and 280 femtoseconds, all of which carried energies of 1000 electronvolts. The team found that this treatment also created hollow electrons, stripping the nitrogen atoms from the inside out. But while the longer pulses steadily pulled each electron off the molecule, the shorter pulse stopped with the innermost electrons. This is because there is not enough time for the outer electrons to fill the holes left by the inner electrons, Berrah said. The outer electrons move down on a characteristic timescale set by nature, called the Auger clock, of about 7 femtoseconds. The 4-femtosecond pulse zips through the molecule before the outer electrons have a chance to drop down. The physicists call this process “frustrated absorption.” “This is very good news for biomolecules,” Berrah said. “It’s promising for single molecule imaging. We can deposit the intense radiation without damaging the molecule that we want to study.” These studies provide “increasing confidence in our ability to understand these processes,” Falcone said. They will also help design the next X-ray lasers. “Understanding how light interacts with matter, both single molecules and atoms, will allow us to design parameters of next-generation machine[s] as well.”
Images: 1) An artist’s conception of what images of single molecules taken with the LCLS might look like. The molecule will leave a distinctive pattern of rings and spots on a detector, before it explodes. 2) The hall holding the magnets that make electrons toss off X-rays. Credit: SLAC National Accelerator Lab See Also:
Source: Wired: Wired Science | 30 Jun 2010 | 11:58 am U.S. Opens Space Doors to ChinaThe next time the United States decides to venture into space, it won't be going alone.Source: Discovery News - Top Stories | 30 Jun 2010 | 11:30 am Summer Most Dangerous Time to TravelMost Americans mistakenly believe the winter is the most dangerous time to drive, but it's actually the summer.Source: Livescience.com | 30 Jun 2010 | 11:28 am Fossil sperm whale with huge teeth found in Peruvian desertThe ancient whale used its giant interlocking teeth to hold prey, inflict deep wounds and tear chunks off it. Fossil remains of Leviathan melvillei were found in the Pisco-Ica desert Fossil hunters have recovered the remains of an ancient sperm whale that boasted one of the largest bites of any predator that ever lived. The beast, named Leviathan melvillei after the author of Moby Dick, Herman Melville, had a skull 3 metres long with teeth in its upper and lower jaws that grew to an extraordinary 36cm long. Remains of the whale, including large fragments of its skull, lower jaw and teeth, were found in the sands of the Pisco-Ica desert on the south coast of Peru in 2008, but details of the discovery have only now been released. The extinct whale is thought to have lived between 12m and 13m years ago and was probably a top predator alongside the 20-metre-long giant shark, Carcharocles megalodon, using its huge jaws to capture and kill other marine creatures, such as smaller baleen whales. "This was probably one of the most powerful predators ever found," said Olivier Lambert, a palaeontologist at the Natural History Museum in Paris, who led the study. "I don't think such large teeth have ever been found before." The team, which included researchers from Utrecht University in the Netherlands and the natural history museums of Rotterdam, Pisa, Lima and Brussels, believe the whale was between 13.5 metres and 17.5 metres long, a similar size to modern sperm whales. "This sperm whale could firmly hold large prey with its interlocking teeth, inflict deep wounds and tear large pieces from the body of the victim," the researchers write in the journal Nature (vol 466, p 105). The remains were found in a region of the Pisco-Ica desert that was a shallow lagoon when the whale was alive. The remains of a rich variety of other marine species, including baleen whales, beaked whales, dolphins, porposies, sharks, turtles, seals and sea birds, have been found at the site. Many of the carcasses were probably washed there after the animals died. Several lineages of sperm whale were alive during the Miocene epoch, from 5m to 24m years ago, but they suddenly became much less diverse during climatic cooling at the end of the epoch. Today, there are only three living species: the sperm whale, the pygmy sperm whale and the dwarf sperm whale. Modern sperm whales have smaller teeth in the lower jaw and are almost toothless in the upper jaw. They feed on squid at depth, which they capture by sucking in water. "This new specimen should give us additional information about the past diversity of sperm whales," said Lambert. The fossil will join a collection at the Natural History Museum in Lima, Peru. guardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds Source: Science news, comment and analysis | guardian.co.uk | 30 Jun 2010 | 11:19 am Gigantic Prehistoric Whale Hunted Other WhalesA prehistoric leviathan related to modern sperm whales hunted other whales rather than giant squid. The ancient monster takes its name in part from Herman Melville, author of the novel Moby Dick.Source: Livescience.com | 30 Jun 2010 | 11:03 am 5 Real Hazards of Air TravelAirport body scanners are small change compared with the cosmic rays, loud noise, spread of disease and other hazards of air travel.Source: Livescience.com | 30 Jun 2010 | 11:00 am Giant Whale-Eating Whale FoundThe skull of the 12–13 million-year-old sperm whale fossil found off the coast of Peru measures an astounding 10 feet long.Source: Discovery News - Top Stories | 30 Jun 2010 | 11:00 am What will get sick from the slick?investigates five of the Gulf of Mexico's signature species.Source: NatureNews - All articles published today - nature.com science feeds | 30 Jun 2010 | 11:00 am Cure for Diabetes Approaches RealityResearchers say they've managed to eliminate the disease in rats using transplanted pig cells.Source: Discovery News - Top Stories | 30 Jun 2010 | 10:32 am Beautiful New Image of a Rare Blue Nebula
This wispy blue cloud of gas and dust is a star-forming region surrounding the star R Coronae Australis, which is about 420 light-years away. The new portrait was taken with the Wide Field Imager at the La Silla Observatory in Chile. The image, a combination of 12 separate snapshots in three different colors, depicts a young family of stars still embedded in and interacting with the cloud of dust and gas from which they formed. The image spans about 4 light-years, and focuses on a nascent star-forming region located in the small, tiara-shaped constellation Coronae Australis, the Southern Crown. The infant stars there give off hot, intense radiation, and the surrounding gas and dust either reflects or absorbs this radiation and re-emits it at a different wavelength. While most nebulae glow with a characteristic red tint, the R Coronae Australis region takes an unusual blue hue. The stars are about the mass of the sun, and don’t emit enough ultraviolet light to strip the surrounding hydrogen gas of its electrons, which would produce the familiar red glow. The blue fog is mostly due to starlight reflecting off small dust particles. In some regions, like the dark band that crosses the image from the bottom left, the starlight is completely absorbed by dust. Any stars hiding in this region would only be visible with an infrared telescope that can detect their heat. High-resolution versions of the image are here. Image: ESO See Also:
Source: Wired: Wired Science | 30 Jun 2010 | 10:26 am Ants Use Velcro Claws to Ambush Heavy PreyVelcro-like hooks let ants take down prey 13,000 times the weight of a single ant.Source: Livescience.com | 30 Jun 2010 | 9:53 am Andrea Doria Bell Rings Out AgainThe Italian ocean liner famously sank in the Atlantic in 1956.Source: Discovery News - Top Stories | 30 Jun 2010 | 9:13 am Hurricane Alex Delays Oil Spill Cleanup EffortsChurned up waves and strong winds forced the suspension of oil skimming and booming operations.Source: Discovery News - Top Stories | 30 Jun 2010 | 8:50 am Ocean Plastic That Will SuckSwedish home appliance manufacturer Electrolux plans to recycle plastic from the ocean and turn it into vacuum cleaners.Source: Discovery News - Top Stories | 30 Jun 2010 | 6:12 am Android's Openness Will Doom iPhone 4Google's Android operating system will be on many more phones than is possible with the iPhone 4.Source: Discovery News - Top Stories | 30 Jun 2010 | 5:46 am
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The newly described fossils, which have yet to be given a species name, make Grypania less solitary. They lived at roughly the same time — Grypania in what is now the northern United States, the new fossils in Gabon. By raising the possiblity that multicellularity was a trend rather than an aberration, they also hint at an answer to the question of why complex life evolved, not just when.
