ScienceDaily — Data from NASA's Cassini spacecraft have revealed Saturn's moon Titan likely harbors a layer of liquid water under its ice shell.
Researchers saw a large amount of squeezing and stretching as the moon orbited Saturn. They deduced that if Titan were composed entirely of stiff rock, the gravitational attraction of Saturn would cause bulges, or solid "tides," on the moon only 3 feet (1 meter) in height. Spacecraft data show Saturn creates solid tides approximately 30 feet (10 meters) in height, which suggests Titan is not made entirely of solid rocky material. The finding appears in today's edition of the journal Science.
"Cassini's detection of large tides on Titan leads to the almost inescapable conclusion that there is a hidden ocean at depth," said Luciano Iess, the paper's lead author and a Cassini team member at the Sapienza University of Rome, Italy. "The search for water is an important goal in solar system exploration, and now we've spotted another place where it is abundant."
Saturday, June 30, 2012
Friday, June 29, 2012
(Phys.org) -- Archaeologists working at the site of La Corona in Guatemala have discovered a 1,300 year-old year-old Maya text that provides only the second known reference to the so-called “end date” for the Maya calendar on December 21, 2012. The discovery, one of the most significant hieroglyphic find in decades, was announced today at the National Palace in Guatemala.
“This text talks about ancient political history rather than prophecy,” says Marcello A. Canuto, Director of Tulane’s Middle American Research Institute and co-director of the excavations at the Maya ruins of La Corona. “This new evidence suggests that the 13 Bak’tun date was an important calendrical event that would have been celebrated by the ancient Maya; however, they make no apocalyptic prophecies whatsoever regarding the date," says Canuto.
La Corona for many decades has been known as the enigmatic “Site Q,” the source of many looted sculptures whose whereabouts had remained a mystery until its rediscovery only fifteen years ago. For the past five years, Marcello A. Canuto and Tomás Barrientos Q. (Director of the Centro de Investigaciones Arqueológicas y Antropológicas at Universidad del Valle de Guatemala) have directed the La Corona Regional Archaeological Project (PRALC) which has been investigating this intriguing Classic Maya city and its jungle environs.
Thursday, June 28, 2012
Two eight-ounce American servings of coffee per day lower risk of heart failure.
ScienceDaily — While current American Heart Association heart failure prevention guidelines warn against habitual coffee consumption, some studies propose a protective benefit, and still others find no association at all. Amidst this conflicting information, research from Beth Israel Deaconess Medical Center attempts to shift the conversation from a definitive yes or no, to a question of how much.
"Our results did show a possible benefit, but like with so many other things we consume, it really depends on how much coffee you drink," says lead author Elizabeth Mostofsky, MPH, ScD, a post-doctoral fellow in the cardiovascular epidemiological unit at BIDMC. "And compared with no consumption, the strongest protection we observed was at about four European, or two eight-ounce American, servings of coffee per day."
The study published June 26 online in the journal Circulation: Heart Failure, found that these moderate coffee drinkers were at 11 percent lower risk of heart failure.
Data was analyzed from five previous studies -- four conducted in Sweden, one in Finland -- that examined the association between coffee consumption and heart failure. The self-reported data came from 140,220 participants and involved 6,522 heart failure events.
Wednesday, June 27, 2012
Investigators out to uncover the truth about UFO's.
Credit: Chi Ma / Caltech
The new mineral, panguite, has been discovered in a 40 year-old meteorite.
In 1969, an exploding fireball tore through the sky over Mexico, scattering thousands of pieces of meteorite across the state of Chihuahua. More than 40 years later, the Allende meteorite is still serving the scientific community as a rich source of information about the early stages of our solar system's evolution. Recently, scientists from the California Institute of Technology (Caltech) discovered a new mineral embedded in the space rock—one they believe to be among the oldest minerals formed in the solar system.
Dubbed panguite, the new titanium oxide is named after Pan Gu, the giant from ancient Chinese mythology who established the world by separating yin from yang to create the earth and the sky. The mineral and the mineral name have been approved by the International Mineralogical Association's Commission on New Minerals, Nomenclature and Classification. A paper outlining the discovery and the properties of this new mineral will be published in the July issue of the journal American Mineralogist, and is available online now.
"Panguite is an especially exciting discovery since it is not only a new mineral, but also a material previously unknown to science," says Chi Ma, a senior scientist and director of the Geological and Planetary Sciences division's Analytical Facility at Caltech and corresponding author on the paper. Keep on reading...
Tuesday, June 26, 2012
Monday, June 25, 2012
Introducing the Hiriko Fold...
The forthcoming Hiriko Fold doesn't fly, but it does fold.
To make this work, regular controls had to be replaced with drive-by-wire, and the accelerator, steering wheel and brake are gone in favor of an aerospace-type yoke that (as in a Segway), is moved forward to move the vehicle forward, and back for reversing. Left and right are for steering.
Just like in the Jetsons' car (and the 1950s BMW Isetta), the driver climbs out through the glass canopy. It's strictly for the urban driver, with top speed of about 31 mph, and range of 75 miles on quick-recharge (15 minutes) lithium-ion batteries. Electric motors are at the car's four wheels. It can be registered as a quadricycle or motorcycle in some markets.
Sunday, June 24, 2012
Theory life came from space gets a boost...
ScienceDaily — You can freeze it, thaw it, vacuum dry it and expose it to radiation, but still life survives. ESA's research on the International Space Station is giving credibility to theories that life came from outer space -- as well as helping to create better sunscreens.
n 2008 scientists sent the suitcase-sized Expose-E experiment package to the Space Station filled with organic compounds and living organisms to test their reaction to outer space.
When astronauts venture on a spacewalk, hours are spent preparing protective suits to survive the hostile conditions. No effort was made to protect the bacteria, seeds, lichen and algae attached to the outside of the Space Station, however.[...]
The samples returned to Earth in 2009 and the results have now been published in a special issue of the journal Astrobiology.
Lichen have proven to be tough cookies -- back on Earth, some species continue to grow normally.
René explains, "These organisms go into a dormant state waiting for better conditions to arrive."
Saturday, June 23, 2012
Awesome dancing in the sky...
After 10 years of archaeological investigations, researchers have concluded that Stonehenge was built as a monument to unify the peoples of Britain, after a long period of conflict and regional difference between eastern and western Britain.
Its stones are thought to have symbolized the ancestors of different groups of earliest farming communities in Britain, with some stones coming from southern England and others from west Wales.
The teams, from the universities of Sheffield, Manchester, Southampton, Bournemouth and University College London, all working on the Stonehenge Riverside Project (SRP), explored not just Stonehenge and its landscape but also the wider social and economic context of the monument's main stages of construction around 3,000 BC and 2,500 BC.
"When Stonehenge was built", said Professor Mike Parker Pearson of the University of Sheffield, "there was a growing island-wide culture – the same styles of houses, pottery and other material forms were used from Orkney to the south coast. This was very different to the regionalism of previous centuries. Stonehenge itself was a massive undertaking, requiring the labour of thousands to move stones from as far away as west Wales, shaping them and erecting them. Just the work itself, requiring everyone literally to pull together, would have been an act of unification."
Stonehenge may have been built in a place that already had special significance for prehistoric Britons. The SRP team have found that its solstice-aligned Avenue sits upon a series of natural landforms that, by chance, form an axis between the directions of midsummer sunrise and midwinter sunset. Keep on reading...
Friday, June 22, 2012
Robots Get A Feel For The World from USC Viterbi on Vimeo.
Sensor gives robots better than human touch.
Researchers have developed a mechanical “finger” called the BioTac, made up of a rigid central sensor surrounded by liquid and covered in a flexible skin. When the BioTac strokes a surface, that surface’s texture produces unique vibrations in the skin, which has ridges like those seen in a human fingerprint. And the BioTac’s software can interpret those vibrations, along with the force that the surface exerts on the mechanical finger, to identify 117 different textures with a 95 percent success rate. In fact, when it came to distinguishing between textures, the BioTac actually out-performed humans.
[via Pop Sci]
Thursday, June 21, 2012
Until now, Earth was the only planet known to have vast reservoirs of water in its interior. Scientists analyzed the water content of two Martian meteorites originating from inside the Red Planet. They found that the amount of water in places of the Martian mantle is vastly larger than previous estimates and is similar to that of Earth's. The results not only affect what we know about the geologic history of Mars, but also have implications for how water got to the Martian surface. The data raise the possibility that Mars could have sustained life.
The research was led by former Carnegie postdoctoral scientist Francis McCubbin, now at the University of New Mexico. The analysis was performed by Carnegie Institution investigator Erik Hauri and team and is published in the journal Geology.
The scientists analyzed what are called shergottite meteorites. These are fairly young meteorites that originated by partial melting of the Martian mantle—the layer under the crust—and crystallized in the shallow subsurface and on the surface. They came to Earth when ejected from Mars approximately 2.5 million years ago. Meteorite geochemistry tells scientists a lot about the geological processes the planet underwent.
"We analyzed two meteorites that had very different processing histories," explained Hauri. "One had undergone considerable mixing with other elements during its formation, while the other had not. We analyzed the water content of the mineral apatite and found there was little difference between the two even though the chemistry of trace elements was markedly different. The results suggest that water was incorporated during the formation of Mars and that the planet was able to store water in its interior during the planet's differentiation."
Wednesday, June 20, 2012
NASA / GSFC / SVS
Scientists have mapped Shackleton Crater ice...
The scientists investigated Shackleton Crater, which sits almost directly on the moon's south pole. The crater, named after the Antarctic explorer Ernest Shackleton, is more than 12 miles wide (19 kilometers) and 2 miles deep (3 kilometers) — about as deep as Earth's ocean.
The interiors of polar craters on the moon are in nearly perpetual darkness, making them cold traps that researchers have long suspected might be home to vast amounts of frozen water and thus key candidates for human exploration. However, previous orbital and Earth-based observations of lunar craters have yielded conflicting interpretations over whether ice is there.
For instance, the Japanese spacecraft Kaguya saw no discernible signs of ice within Shackleton Crater, but NASA's LCROSS probe analyzed Cabeus Crater near the moon's south pole and determined that it had as much as 5 percent water by mass.
Now scientists who have mapped Shackleton Crater with unprecedented detail have found evidence of ice inside the crater.
NASA's Lunar Reconnaissance Orbiter essentially illuminated the crater's interior with infrared laser light, measuring how reflective it was. The crater's floor is more reflective than that of other nearby craters, suggesting it had ice.
"Water ice in amounts of up to 20 percent is a viable possibility,"... Keep on reading...
Women who work at night face a higher risk of breast cancer...
ScienceDaily — The results of a study carried out by the researchers of the Inserm unit 1018 (Centre for research in Epidemiology and Population Health) and published in the International Journal of Cancer show that the risk of developing breast cancer is higher among women who have worked at night. The study, carried out in France and named the CECILE study, compared the careers of 1200 women who had developed breast cancer between 2005 and 2008 with the careers of 1300 other women.
Breast cancer is the number one cause of female mortality. It affects 100 out of 100,000 women per year in developed countries. Each year, more than 1.3 million new cases are diagnosed, 53,000 of these in France.
The risk factors of breast cancer are varied. They include genetic mutations, late first pregnancy, low parity or hormone therapy, but other causes of breast cancer such as way of life, environmental or professional causes have not yet been completely identified. Keep on reading...
Tuesday, June 19, 2012
NASA’s Voyager 1 NASA’s Voyager 1 spacecraft nearing edge of solar system
Capturing CO2 and injecting it into the ground could cause earthquakes?
A proposed method of cutting harmful carbon emissions in the atmosphere by storing them underground risks causing earthquakes and is unlikely to succeed, a US study said Monday.
The warning came in a Perspective article in the Proceedings of the National Academy of Sciences, just days after another independent US study warned that carbon capture and storage (CCS) risked causing earthquakes.
CCS is currently considered a "viable strategy" by the UN Intergovernmental Panel on Climate Change for pollution control from coal-based electrical power generation and other industrial sources of carbon dioxide, said the PNAS study.
But while no large-scale projects are yet under way, the huge volume of fluid that would need to be stored below ground for long periods of time make the notion unrealistic, argued the study by experts at Stanford University in California.
"There is a high probability that earthquakes will be triggered by injection of large volumes of CO2 into the brittle rocks commonly found in continental interiors," said the article by Mark Zobacka and Steven Gorelick, professors in the departments of Geophysics and Environmental Earth System Science.
Monday, June 18, 2012
(Phys.org) -- A new university-led study with NASA participation finds ancient Antarctica was much warmer and wetter than previously suspected. The climate was suitable to support substantial vegetation -- including stunted trees -- along the edges of the frozen continent.
The team of scientists involved in the study, published online June 17 in Nature Geoscience, was led by Sarah J. Feakins of the University of Southern California in Los Angeles, and included researchers from NASA's Jet Propulsion Laboratory in Pasadena, Calif., and Louisiana State University in Baton Rouge.
By examining plant leaf wax remnants in sediment core samples taken from beneath the Ross Ice Shelf, the research team found summer temperatures along the Antarctic coast 15 to 20 million years ago were 20 degrees Fahrenheit (11 degrees Celsius) warmer than today, with temperatures reaching as high as 45 degrees Fahrenheit (7 degrees Celsius). Precipitation levels also were found to be several times higher than today.
"The ultimate goal of the study was to better understand what the future of climate change may look like," said Feakins, an assistant professor of Earth sciences at the USC Dornsife College of Letters, Arts and Sciences. "Just as history has a lot to teach us about the future, so does past climate. This record shows us how much warmer and wetter it can get around the Antarctic ice sheet as the climate system heats up. This is some of the first evidence of just how much warmer it was." Keep on reading...
Sunday, June 17, 2012
Paralyzed woman moves robotic arm by her mind.
The immune system removes beta-amyloid, the main Alzheimer's-causing substance in the brain.
ScienceDaily — Recent work in mice suggested that the immune system is involved in removing beta-amyloid, the main Alzheimer's-causing substance in the brain. Researchers have now shown for the first time that this may apply in humans.
Researchers at the Peninsula College of Medicine and Dentistry, University of Exeter with colleagues in the National Institute on Aging in the USA and in Italy screened the expression levels of thousands of genes in blood samples from nearly 700 people. The telltale marker of immune system activity against beta-amyloid, a gene called CCR2, emerged as the top marker associated with memory in people.
The team used a common clinical measure called the Mini Mental State Examination to measure memory and other cognitive functions.
The previous work in mice showed that augmenting the CCR2-activated part of the immune system in the blood stream resulted in improved memory and functioning in mice susceptible to Alzheimer's disease. Keep on reading...
Saturday, June 16, 2012
Video: iCub robot named DeeChee learns language like a baby.
A hypothetical parallel world consisting of mirror particles...
ScienceDaily — In a paper recently published in European Physical Journal (EPJ) C, researchers hypothesised the existence of mirror particles to explain the anomalous loss of neutrons observed experimentally. The existence of such mirror matter had been suggested in various scientific contexts some time ago, including the search for suitable dark matter candidates.
Theoretical physicists Zurab Berezhiani and Fabrizio Nesti from the University of l'Aquila, Italy, reanalysed the experimental data obtained by the research group of Anatoly Serebrov at the Institut Laue-Langevin, France. It showed that the loss rate of very slow free neutrons appeared to depend on the direction and strength of the magnetic field applied. This anomaly could not be explained by known physics.
Berezhiani believes it could be interpreted in the light of a hypothetical parallel world consisting of mirror particles. Each neutron would have the ability to transition into its invisible mirror twin, and back, oscillating from one world to the other. The probability of such a transition happening was predicted to be sensitive to the presence of magnetic fields, and could therefore be detected experimentally.
Friday, June 15, 2012
UK researchers create a wearable power harvester.
(PHYSORG)- Battery-powered devices could soon be a thing of the past thanks to a group of UK researchers who have created a novel energy harvester to power some of the latest wearable gadgets.
By strapping the energy harvester to the knee joint, a user could power body-monitoring devices such as heart rate monitors, pedometers and accelerometers by simply walking and not have the worry of running out of power and replacing batteries. Soldiers may find this device particularly useful as they often have to carry up to 10kg of power equipment when on foot patrol.
The device has been presented today, 15 June, in Smart Materials and Structures journal by researchers from Cranfield University, The University of Liverpool and University of Salford.
The energy harvesting device, which is designed to fit onto the outside of the knee, is circular and consists of an outer ring and central hub. The outer ring rotates as the knee joint goes through a walking motion. The outer ring is fitted with 72 plectra which "pluck" four energy-generating arms attached to the inner hub.
As an individual plectrum deflects off one of the arms – which are called bimorphs – it causes it to vibrate, much like a guitar string, and generates the electrical energy.
Thursday, June 14, 2012
Scientists find 927-square-mile hydrocarbon lake in Titan's tropical region.
(AP) — In a surprise find, scientists say they have spotted hints of a methane-rich lake and several ponds near the equator of Saturn's biggest moon.
Lakes were previously spied near Titan's polar regions. It was long thought that bodies of liquid could not exist near the tropics because they would evaporate.
"This discovery was completely unexpected because lakes are not stable at tropical latitudes," said planetary scientist Caitlin Griffith of the University of Arizona, who led the discovery team.
By measuring reflected sunlight from Titan's surface and atmosphere, the international Cassini spacecraft detected a dark region near the landing site of Huygens, a companion probe that parachuted to Titan's equator in 2005.
Scientists said further analysis of the dark feature suggests the presence of a 927-square-mile (2,400-square-kilometer) hydrocarbon lake — twice as big as Lake Champlain, a freshwater lake that borders upstate New York and Vermont. Near the tropical lake were hints of four shallow ponds similar in size and depth to marshes on Earth.
The findings were detailed in Thursday's issue of the journal Nature.
Wednesday, June 13, 2012
Company makes "kamikaze drone" that is portable by a soldier.
Errant drone strikes have been blamed for killing and injuring scores of civilians throughout Pakistan and Afghanistan, giving the US government a black eye as it targets elusive terrorist groups. The Predator and Reaper drones deployed in these regions typically carry 100-pound (45-kilogram) laser-guided Hellfire missiles or 500-pound GPS-guided smart bombs that can reduce buildings to smouldering rubble.
The new Switchblade drone, by comparison, weighs less than six pounds (2.7 kilograms) and can take out a sniper on a rooftop without blasting the building to bits. It also enables soldiers in the field to identify and destroy targets much more quickly by eliminating the need to call in a strike from large drones that may be hundreds of kilometres away.
"This is a precision strike weapon that causes as minimal collateral damage as possible," said William I. Nichols, who led the Army's testing effort of the Switchblades at Redstone Arsenal near Huntsville, Alabama.
The 61-centimetre-long Switchblade is so named because its wings fold into the fuselage for transport and spring out after launch. It is designed to fit into a soldier's rucksack and is fired from a mortar-like tube. Once airborne, it begins sending back live video and GPS coordinates to a hand-held control set clutched by the soldier who launched it.
Read more here...
NASA illustration of NuSTAR
The Nuclear Spectroscopic Telescope Array (NuSTAR)is scheduled to be launched today. It will use X-ray vision to hunt for black holes.
(PHYSORG)- NASA is poised to launch on Wednesday a sophisticated orbiting telescope that uses high-energy X-ray vision to hunt for black holes in the universe.
The Nuclear Spectroscopic Telescope Array (NuSTAR) will first be carried into the skies by a jet which will deploy a rocket that sends the satellite into space, NASA said.
"Why launch from the air? Plane-assisted launches are less expensive than those that take place from the ground. Less fuel is needed to boost cargo away from the pull of Earth's gravity," the US space agency said in a statement.
The project aims to study energetic phenomena such as black holes and the explosions of massive stars.
Orbital Sciences Corporation designed and manufactured the telescope and will send it into orbit from its own Pegasus air-launched rocket, which is attached to the underside of the company's L-1011 Stargazer aircraft.
Tuesday, June 12, 2012
NASA is testing concepts for a potential asteroid mission underwater.
(PHYSORG)- An international crew of aquanauts is settling into its home on the ocean floor, where the team will spend 12 days testing concepts for a potential asteroid mission. The expedition is the 16th excursion of the NASA Extreme Environment Mission Operations (NEEMO). The crew of four began its mission in the National Oceanic and Atmospheric Administration's Aquarius Reef Base undersea research habitat off the coast of Key Largo, Fla., at 11:04 a.m. EDT Monday.
NEEMO sends groups of astronauts, engineers and scientists to live in the Aquarius lab, 63 feet below the surface of the Atlantic Ocean. The laboratory is located in the Florida Keys National Marine Sanctuary. For NASA, Aquarius provides a convincing simulation to space exploration, and NEEMO crew members experience some of the same tasks and challenges under water that they would in space.
The NEEMO 16 mission will focus on three areas related to asteroid missions. The crew of aquanauts will investigate communication delays, restraint and translation techniques, and optimum crew size. Keep on reading...
Monday, June 11, 2012
If your father and grandfather were older when you were conceived, you may live longer...
If your father and grandfather waited until they were older before reproducing, you might experience life-extending benefits.
Biologists assume that a slow pace of aging requires that the body invest more resources in repairing cells and tissues.
A new Northwestern University study suggests that our bodies might increase these investments to slow the pace of aging if our father and grandfather waited until they were older before having children.
"If your father and grandfather were able to live and reproduce at a later age, this might predict that you yourself live in an environment that is somewhat similar — an environment with less accidental deaths or in which men are only able to find a partner at later ages," said Dan T.A. Eisenberg, lead author of the study and a doctoral candidate in anthropology at Northwestern. "In such an environment, investing more in a body capable of reaching these late ages could be an adaptive strategy from an evolutionary perspective."
Christopher W. Kuzawa, co-author of the study, associate professor of anthropology at Northwestern and a faculty fellow at the University's Institute for Policy Research, said the new findings are fascinating.
Sunday, June 10, 2012
Sandia labs researchers design self-guided .50-caliber bullet.
A team of Sandia labs researchers has come up with a novel design for a guided bullet.
Engineer Larry Shipers showed a rough sketch of the proposal to Popular Science, detailing how the new bullet should overcome some basic issues faced by weapons designers.
First of all, the bullet is actually not a bullet in the traditional sense. It is not spin-stabilised and it is much larger than an ordinary full-metal jacket bullet, as it has accommodate guidance electronics based on an 8-bit chip, an optical sensor and aerodynamic control surfaces.
The resulting design is more than twice the length of a regular .50 caliber bullet and as it is not supposed to spin, it would have to be fired out of a smoothbore barrel, which would have to be retrofitted to existing .50 cal weapons. The guidance system relies on a small laser sensor at the tip of the bullet and a cone-shaped control surface at the back.... Keep on reading...
Neutrino researchers admit Einstein was right about speed of light.
(PHYSORG)- Scientists on Friday said that an experiment which challenged Einstein's theory on the speed of light had been flawed and that sub-atomic particles -- like everything else -- are indeed bound by the universe's speed limit.
Researchers working at the European Centre for Nuclear Research (CERN) caused a storm last year when they published experimental results showing that neutrinos could out-pace light by some six kilometres (3.7 miles) per second.
The findings threatened to upend modern physics and smash a hole in Albert Einstein's 1905 theory of special relativity, which described the velocity of light as the maximum speed in the cosmos.
But CERN now says that the earlier results were wrong and faulty kit was to blame.
"Although this result isn't as exciting as some would have liked, it is what we all expected deep down," said the centre's research director Sergio Bertolucci.
"The story captured the public imagination, and has given people the opportunity to see the scientific method in action. Keep on reading...
Saturday, June 9, 2012
Nuclear fusion power is a step closer to reality.
(PHYSORG)- Imagine a world without man-made climate change, energy crunches or reliance on foreign oil. It may sound like a dream world, but University of Tennessee, Knoxville, engineers have made a giant step toward making this scenario a reality.
UT researchers have successfully developed a key technology in developing an experimental reactor that can demonstrate the feasibility of fusion energy for the power grid. Nuclear fusion promises to supply more energy than the nuclear fission used today but with far fewer risks.
Mechanical, aerospace and biomedical engineering professors David Irick, Madhu Madhukar and Masood Parang are engaged in a project involving the United States, five other nations, and the European Union, known as ITER. UT researchers completed a critical step this week for the project by successfully testing their technology this week that will insulate and stabilize the central solenoid—the reactor's backbone.
ITER is building a fusion reactor that aims to produce 10 times the amount of energy that it uses. The facility is now under construction near Cadarache, France, and will begin operations in 2020.
"The goal of ITER is to help bring fusion power to the commercial market," Madhukar said. "Fusion power is safer and more efficient than nuclear fission power. There is no danger of runaway reactions like what happened in nuclear fission reactions in Japan and Chernobyl, and there is little radioactive waste." Unlike today's nuclear fission reactors, fusion uses a similar process as that which powers the sun.
Friday, June 8, 2012
Thursday, June 7, 2012
ScienceDaily — Scientists have developed a new technique to accurately measure the weight and size of dinosaurs and discovered they are not as heavy as previously thought.
University of Manchester biologists used lasers to measure the minimum amount of skin required to wrap around the skeletons of modern-day mammals, including reindeer, polar bears, giraffes and elephants.
They discovered that the animals had almost exactly 21% more body mass than the minimum skeletal 'skin and bone' wrap volume, and applied this to a giant Brachiosaur skeleton in Berlin's Museum für Naturkunde.
Previous estimates of this Brachiosaur's weight have varied, with estimates as high as 80 tonnes, but the Manchester team's calculations -- published in the journal Biology Letters -- reduced that figure to just 23 tonnes. The team says the new technique will apply to all dinosaur weight measurements.
Lead author Dr Bill Sellers said: "One of the most important things palaeobiologists need to know about fossilised animals is how much they weighed. This is surprisingly difficult, so we have been testing a new approach. We laser scanned various large mammal skeletons, including polar bear, giraffe and elephant, and calculated the minimum wrapping volume of the main skeletal sections.
Wednesday, June 6, 2012
Tuesday, June 5, 2012
Birds ended the reign of giant insects.
ScienceDaily — Giant insects ruled the prehistoric skies during periods when Earth's atmosphere was rich in oxygen. Then came the birds. After the evolution of birds about 150 million years ago, insects got smaller despite rising oxygen levels, according to a new study by scientists at the University of California, Santa Cruz.
Insects reached their biggest sizes about 300 million years ago during the late Carboniferous and early Permian periods. This was the reign of the predatory griffinflies, giant dragonfly-like insects with wingspans of up to 28 inches (70 centimeters). The leading theory attributes their large size to high oxygen concentrations in the atmosphere (over 30 percent, compared to 21 percent today), which allowed giant insects to get enough oxygen through the tiny breathing tubes that insects use instead of lungs.
The new study takes a close look at the relationship between insect size and prehistoric oxygen levels. Matthew Clapham, an assistant professor of Earth and planetary sciences at UC Santa Cruz, and Jered Karr, a UCSC graduate student who began working on the project as an undergraduate, compiled a huge dataset of wing lengths from published records of fossil insects, then analyzed insect size in relation to oxygen levels over hundreds of millions of years of insect evolution. Their findings are published in the June 4 online early edition of the Proceedings of the National Academy of Sciences (PNAS). Read more here...
Monday, June 4, 2012
Was Earth hit by radiation from a supernova in the 8th century?
(PHYSORG)- In the late eighth century, Earth was hit by a mystery blast of cosmic rays, according to a Japanese study that found a relic of the powerful event in cedar trees.
Analysis of two ancient trees found a surge in carbon-14 -- a carbon isotope that derives from cosmic radiation -- which occurred just in AD 774 and AD 775, the team report in the journal Nature on Sunday.
Earth is battered by protons and other sub-atomic particles which are blasted across space by high-energy sources.
The particles collide with the stratosphere and react with nitrogen to create carbon-14, which is then absorbed into the biosphere.
A team led by Fusa Miyake of Nagoya University found that levels of carbon-14 in the two cedars were about 1.2 percent higher in 774 and 775 compared to other years.
This may not sound much, but in relation to background concentrations of carbon-14, the difference is huge.
One source of cosmic rays is the Sun, whose activity varies in phases called Schwabe cycles. Our star also throws the occasional tantrum, spouting bursts of energy called solar flares.
But Miyake's team say that the cosmic whack of 774-775 cannot be attributed to the Schwabe cycle of the time -- and it is far bigger than any known flare from the Sun.
The other possibility is a supernova, or a star that explodes at the end of its life in a welter of gamma radiation.
Sunday, June 3, 2012
Tech Take: Clayton Morris shares tips on how to borrow e-books from your local library.
Digital lending libraries for Kindle and Nook
Digital lending libraries for Kindle and Nook
Daily consumption of dark chocolate reduces heart disease.
ScienceDaily — Daily consumption of dark chocolate can reduce cardiovascular events, such as heart attacks and strokes, in people with metabolic syndrome (a cluster of factors that increases the risk of developing heart disease and diabetes), finds a study published in the British Medical Journal.Cardiovascular disease is the leading cause of death worldwide. Dark chocolate (containing at least 60% cocoa solids) is rich in flavonoids -- known to have heart protecting effects -- but this has only been examined in short term studies.
So a team of researchers from Melbourne, Australia used a mathematical model to predict the long-term health effects and cost effectiveness of daily dark chocolate consumption in 2,013 people already at high risk of heart disease.
All participants had high blood pressure and met the criteria for metabolic syndrome, but had no history of heart disease or diabetes and were not on blood pressure lowering therapy.
With 100% compliance (best case scenario), the researchers show that daily dark chocolate consumption could potentially avert 70 non-fatal and 15 fatal cardiovascular events per 10,000 people treated over 10 years.
Saturday, June 2, 2012
Friday, June 1, 2012
(MedicalXpress)- Rats with spinal cord injuries and severe paralysis are now walking (and running) thanks to researchers at EPFL. Published in the June 1, 2012 issue of Science, the results show that a severed section of the spinal cord can make a comeback when its own innate intelligence and regenerative capacity—what lead author Grégoire Courtine of EPFL calls the "spinal brain"—is awakened. The study, begun five years ago at the University of Zurich, points to a profound change in our understanding of the central nervous system. It is yet unclear if similar rehabilitation techniques could work for humans, but the observed nerve growth hints at new methods for treating paralysis.
"After a couple of weeks of neurorehabilitation with a combination of a robotic harness and electrical-chemical stimulation, our rats are not only voluntarily initiating a walking gait, but they are soon sprinting, climbing up stairs and avoiding obstacles," explains Courtine, who holds the International Paraplegic Foundation (IRP) Chair in Spinal Cord Repair at EPFL.
Neuroplasticity after severe injury
It is well known that the brain and spinal cord can adapt and recover from moderate injury, a quality known as neuroplasticity. But until now the spinal cord expressed so little plasticity after severe injury that recovery was impossible. Courtine's research proves that, under certain conditions, plasticity and recovery can take place in these severe cases—but only if the dormant spinal column is first woken up.