The Edge of Life
|Lars Peter Nielsen||October 25th 2012|
Researchers at Aarhus University, Denmark, made a sensational discovery almost three years ago when they measured electric currents in the seabed. It was unclear as to what was conducting the current, but the researchers imagined the electric currents might run between different bacteria via a joint external wiring network. The researchers have now solved the mystery. It turns out that the whole process takes place inside bacteria that are one centimetre long. They make up a kind of live electric cable that no one had ever imagined existed. Each one of these 'cable bacteria' contains a bundle of insulated wires that conduct an electric current from one end to the other. Read more ..
The Edge of Life
|Robert Sanders||October 25th 2012|
Bacteria have a bad rap as agents of disease, but scientists are increasingly discovering their many benefits, such as maintaining a healthy gut. Triggered by the presence of bacteria, the single-celled choanoflagellate Salpingoeca rosetta divides and stays with its sisters to form a colony. One reason may be that the colony is a more efficient way of capturing food, like a “Death Star” sitting amidst the bacteria and chowing down. The colony is about 15 microns in diameter, or less than one-thousandth of an inch across. Scanning electron microscope image courtesy of Nicole King.
A new study now suggests that bacteria may also have helped kick off one of the key events in evolution: the leap from one-celled organisms to many-celled organisms, a development that eventually led to all animals, including humans. Read more ..
The Edge of Earth
|Jade Boyd||October 24th 2012|
A new Rice University-led study finds that a deep connection about 50 miles underground can explain the enigmatic behavior of two of Earth's most notable volcanoes, Hawaii's Mauna Loa and Kilauea. The study, the first to model paired volcano interactions, explains how a link in Earth's upper mantle could account for Kilauea and Mauna Loa's competition for the same deep magma supply and their simultaneous "inflation," or bulging upward, during the past decade.
The research offers the first plausible model that can explain both the opposing long-term eruptive patterns at Mauna Loa and Kilauea -- when one is active the other is quiet -- as well as the episode in 2003-2007 when GPS records showed that each bulged notably due to the pressure of rising magma. The study was conducted by scientists at Rice University, the University of Hawaii, the U.S. Geological Survey (USGS) and the Carnegie Institution of Washington. Read more ..
The Edge of Climate Change
|Maria-José Viñas||October 24th 2012|
The steady and dramatic decline in the sea ice cover of the Arctic Ocean over the last three decades has become a focus of media and public attention. At the opposite end of the Earth, however, something more complex is happening.
A new NASA study shows that from 1978 to 2010 the total extent of sea ice surrounding Antarctica in the Southern Ocean grew by roughly 6,600 square miles every year, an area larger than the state of Connecticut. And previous research by the same authors indicates that this rate of increase has recently accelerated, up from an average rate of almost 4,300 square miles per year from 1978 to 2006.
"There's been an overall increase in the sea ice cover in the Antarctic, which is the opposite of what is happening in the Arctic,” said lead author Claire Parkinson, a climate scientist with NASA's Goddard Space Flight Center, Greenbelt, Md. "However, this growth rate is not nearly as large as the decrease in the Arctic.” Read more ..
The Edge of Medicine
|Yivsam Azgad ||October 23rd 2012|
Hiding deep inside the bone marrow are special cells. They wait patiently for the hour of need, at which point these blood-forming stem cells can proliferate and differentiate into billions of mature blood immune cells to help the body cope with infection, for example, or extra red blood cells for low oxygen levels at high altitudes. Even in emergencies, however, the body keeps to a long-term plan: It maintains a reserve of undifferentiated stem cells for future needs and crises. A research team headed by Prof. Tsvee Lapidot of the Institute’s Immunology Department recently discovered a new type of bodyguard that protects stem cells from over-differentiation. In a paper that appeared in Nature Immunology, they revealed how this rare, previously unknown sub-group of activated immune cells keeps the stem cells in the bone marrow “forever young.”
Blood-forming stem cells live in comfort in the bone marrow, surrounded by an entourage of support cells that cater to their needs and direct their development – the mesenchymal cells. Read more ..
The Geologic Edge
|F.Ossing||October 23rd 2012|
Annual to decadal changes in the earth's magnetic field in a region that stretches from the Atlantic to the Indian Ocean have a close relationship with variations of gravity in this area. From this it can be concluded that outer core processes are reflected in gravity data. This is the result presented by a German-French group of geophysicists in the latest issue of PNAS (Proceedings of the National Academy of Sciences of the United States).
The main field of the Earth's magnetic field is generated by flows of liquid iron in the outer core. The Earth's magnetic field protects us from cosmic radiation particles. Therefore, understanding the processes in the outer core is important to understand the terrestrial shield. Key to this are measurements of the geomagnetic field itself. A second, independent access could be represented by the measurement of minute changes in gravity caused by the fact that the flow in the liquid Earth's core is associated with mass displacements. The research group has now succeeded to provide the first evidence of such a connection of fluctuations in the Earth's gravity and magnetic field. Read more ..
The Edge of Nature
|Yivsam Azgad||October 22nd 2012|
|An atypical microorganism|
Not long ago, some unassuming bacteria found themselves at the center of a scientific controversy: A group claimed that these microorganisms, which live in an environment that is rich in the arsenic-based compound arsenate, could take up that arsenate and use it – instead of the phosphate on which all known life on Earth depends. The claim, since disproved, raised another question: How do organisms living with arsenate pick and choose the right substance?
Chemically, arsenate is nearly indistinguishable from phosphate. Prof. Dan Tawfik of the Biological Chemistry Department says: “Phosphate forms highly stable bonds in DNA and other key biological compounds, while bonds to arsenate are quickly broken. But how does a microorganism surrounded by arsenate distinguish between two molecules that are almost the same size and have identical shapes and ionic properties?”
To investigate, Tawfik, postdoctoral fellow Dr. Mikael Elias, Ph.D. student Alon Wellner and lab assistant Korina Goldin, in collaboration with Tobias Erb and Julia Vorholt of ETH Zurich, looked at a protein in bacteria that takes up phosphate. This protein, called PBP (short for phosphate binding protein), sits near the bacteria’s outer membrane, where it latches onto phosphates and passes them on to pumps that transport them into the cell. Read more ..
The Edge of Medicine
|LaKisha Ladson||October 22nd 2012|
Biologists have teamed up with mechanical engineers from the The University of Texas at Dallas to conduct cell research that provides information that may one day be used to engineer organs. The research sheds light on the mechanics of cell, tissue and organ formation. The research revealed basic mechanisms about how a group of bacterial cells can form large three-dimensional structures.
“If you want to create an organism, the geometry of how a group of cells self-organizes is crucial,” said Dr. Hongbing Lu, professor of mechanical engineering and holder of the Louis Beecherl Jr. Chair at UT Dallas and an author of the study. “We found that cell death leads to wrinkles, and the stiffer the cell the fewer wrinkles.” Read more ..
The Prehistoric Edge
|Esther Harward||October 22nd 2012|
Scientists have discovered why the 'broken world' following the worst extinction of all time lasted so long – it was simply too hot to survive. The end-Permian mass extinction, which occurred around 250 million years ago in the pre-dinosaur era, wiped out nearly all the world's species. Typically, a mass extinction is followed by a 'dead zone' during which new species are not seen for tens of thousands of years. In this case, the dead zone, during the Early Triassic period which followed, lasted for a perplexingly long period: five million years.
A study jointly led by the University of Leeds and China University of Geosciences (Wuhan), in collaboration with the University of Erlangen-Nurnburg (Germany), shows the cause of this lengthy devastation was a temperature rise to lethal levels in the tropics: around 50-60°C on land, and 40°C at the sea-surface. Lead author Yadong Sun, who is based in Leeds while completing a joint PhD in geology, says: "Global warming has long been linked to the end-Permian mass extinction, but this study is the first to show extreme temperatures kept life from re-starting in Equatorial latitudes for millions of years." Read more ..
The Edge of Space
|David Orenstein||October 21st 2012|
The cabin of a spacecraft halfway to Mars would be the least convenient place -- one cannot say “on earth” — for a Salmonella or Pneumococcus outbreak, but a wide-ranging new paper suggests that microgravity and prolonged space flight could give unique advantages to germs. What’s a space agency to do? Brown University and Rhode Island Hospital infectious disease expert Dr. Leonard Mermel offers several ideas. And no, they are not to add more Vitamin C to the Tang, or to give each crew member a bottle of Purell. It’s a lot more complicated than that.
“I’ve been involved for two decades with trying to prevent infections in the intensive care unit and general hospital settings and I’ve been involved with national and international guidelines, but there are a lot of constraints in space I had never thought of before,” said Mermel, who began investigating the infectious disease implications of space flight when he was invited to speak at a NASA-Johnson Space Center symposium in April 2011. Read more ..
The Edge of the Universe
|Oli Usher||October 21st 2012|
Astronomers using the NASA/ESA Hubble Space Telescope have studied a giant filament of dark matter in 3D for the first time. Extending 60 million light-years from one of the most massive galaxy clusters known, the filament is part of the cosmic web that constitutes the large-scale structure of the Universe, and is a leftover of the very first moments after the Big Bang. If the high mass measured for the filament is representative of the rest of the Universe, then these structures may contain more than half of all the mass in the Universe.
The theory of the Big Bang predicts that variations in the density of matter in the very first moments of the Universe led the bulk of the matter in the cosmos to condense into a web of tangled filaments. This view is supported by computer simulations of cosmic evolution, which suggest that the Universe is structured like a web, with long filaments that connect to each other at the locations of massive galaxy clusters. However, these filaments, although vast, are made mainly of dark matter, which is incredibly difficult to observe. Read more ..
The Education Edge
|Viva Sarah Press||October 20th 2012|
Writer’s block for professionals is one thing. But when a student can’t think of how to start an assignment or doesn’t know how to fine-tune an Internet search, schoolwork can quickly turn from educational to frustrating.
That’s where a new Israeli startup called Skills & Knowledge comes in. The company has created an application known as sCoolWork, which helps students write essays better and faster. “As soon as you’re being tasked with writing something, that’s where we kick in,” Shachar Tal, Skills & Knowledge vice president of marketing explains. This isn’t a tool for cheating, but an organizational aid to format an assignment, spell-check it, check grammar, put in a bibliography and even search the Internet more effectively. Opinion leaders say the app “has the potential to substantially influence how people in general, and students specifically, process information.” Moreover, it is teacher approved. Read more ..
The Edge of Nature
|Mark Shwartz||October 20th 2012|
A team of elephant researchers from Stanford University has transformed a remote corner of southern Africa into a high-tech field camp run entirely on sunlight. The seasonal solar-powered research camp gives scientists a rare opportunity to quietly observe, videotape and photograph wild elephants at Mushara waterhole, an isolated oasis in Etosha National Park in Namibia.
"One of the really special aspects of solar energy is that it allows us to be in this incredibly remote area that's closed to tourists and is off the grid," said lead researcher Caitlin O'Connell-Rodwell, an instructor at the Stanford School of Medicine and a collaborating scientist at Stanford's Center for Conservation Biology. She is also co-founder of Utopia Scientific, a non-profit organization that promotes awareness about science, conservation and public health.
"We get to watch elephant society unfold before us in a very quiet environment – no generators, no people, no vehicles," she added.
O'Connell-Rodwell has been studying elephant communication at Mushara for 20 years. She was the first scientist to demonstrate that low-frequency calls produced by elephants generate powerful vibrations in the ground – seismic signals that elephants can feel, and even interpret, via their sensitive trunks and feet.
To identify individual elephants, Stanford undergraduate Patrick Freeman took hundreds of high-resolution photographs using a camera run on solar-powered batteries. His trip to Namibia was supported by a travel grant from the Vice Provost for Undergraduate Education (VPUE) at Stanford. Each year, VPUE provides additional funding to support Stanford undergraduates working in the camp. Read more ..
The Edge of Aging
|Nicole Casals Moore||October 19th 2012|
University of Michigan
Exactly how Alzheimer's disease kills brain cells is still somewhat of a mystery, but University of Michigan researchers have uncovered a clue that supports the idea that small proteins prick holes into neurons.
The team also found that a certain size range of clumps of these proteins are particularly toxic to cells, while smaller and larger aggregates of the protein appear to be benign.
The findings, which appear in the journal PLOS ONE, add important detail to the knowledge base regarding this disease that affects 5.4 million Americans in 2012 but remains incurable and largely untreatable. The results could potentially help pharmaceutical researchers target drugs to the right disease mechanisms. The paper is entitled "Multivariate analyses of amyloid-beta oligomer populations indicate a connection between pore formation and cytotoxicity." Read more ..
The Edge of Space
|Richard Hook||October 19th 2012|
European astronomers have discovered a planet with about the mass of the Earth orbiting a star in the Alpha Centauri system — the nearest to Earth. It is also the lightest exoplanet ever discovered around a star like the Sun. The planet was detected using the HARPS instrument on the 3.6-metre telescope at ESO's La Silla Observatory in Chile.
Alpha Centauri is one of the brightest stars in the southern skies and is the nearest stellar system to our Solar System -- only 4.3 light-years away. It is actually a triple star -- a system consisting of two stars similar to the Sun orbiting close to each other, designated Alpha Centauri A and B, and a more distant and faint red component known as Proxima Centauri. Since the nineteenth century astronomers have speculated about planets orbiting these bodies, the closest possible abodes for life beyond the Solar System, but searches of increasing precision had revealed nothing. Until now. Read more ..
The Edge of Space
|Robert Monroe||October 18th 2012|
University of California - San Diego
Fresh examinations of lunar rocks gathered by Apollo mission astronauts have yielded new insights about the moon's chemical makeup as well as clues about the giant impacts that may have shaped the early beginnings of Earth and the moon.
Geochemist James Day of Scripps Institution of Oceanography at UC San Diego and colleagues Randal Paniello and Frédéric Moynier at Washington University in St. Louis used advanced technological instrumentation to probe the chemical signatures of moon rocks obtained during four lunar missions and meteorites collected from the Antarctic. The data revealed new findings about elements known as volatiles, which offer key information about how planets may have formed and evolved.
The researchers discovered that the volatile element zinc, which they call "a powerful tracer of the volatile histories of planets," is severely depleted on the moon, along with most other similar elements. This led them to conclude that a "planetary-scale" evaporation event occurred in the moon's history, rather than regional evaporation events on smaller scales. Read more ..
The Edge of Food
|David Gilbert||October 15th 2012|
DOE/Joint Genome Instirute
The button mushroom occupies a prominent place in our diet and in the grocery store where it boasts a tasty multibillion-dollar niche, while in nature, Agaricus bisporus is known to decay leaf matter on the forest floor. Now, owing to an international collaboration of two dozen institutions led by the French National Institute for Agricultural Research (INRA) and the U.S. Department of Energy Joint Genome Institute (DOE JGI), the full repertoire of A. bisporus genes has been determined. In particular, new work shows how its genes are actually deployed not only in leaf decay but also wood decay and in the development of fruiting bodies (the above ground part of the mushroom harvested for food). The work also suggests how such processes have major implications for forest carbon management. The analysis of the inner workings of the world's most cultivated mushroom was published online the week of October 8 in the journal, the Proceedings of the National Academy of Sciences (PNAS). Read more ..
The Edge of Health
|Jessica Berman||October 14th 2012|
Scientists are studying the use of mobile phones to track patterns of malaria transmission in endemic nations. The research is part of an effort by many countries to control or eliminate the mosquito-borne disease.
On their own, malaria-carrying mosquitoes can’t travel very far. But the insects that are responsible for nearly one million deaths around the world each year can, and do, hitch rides in the belongings of people who travel. Malaria can also be transmitted to healthy individuals by asymptomatic people who venture from an area where many people are sick with the disease, to a location, such as a city, where residents are seldom exposed to malarial mosquitoes. Such is the case in Kenya, where researchers have determined the disease primarily spreads east from the country’s Lake Victoria region toward Nairobi with people who travel to the country’s capital. Read more ..
The Edge of Physics
|Terrence Sterling||October 13th 2012|
Einstein's theory holds that nothing could move faster than the speed of light, but Professor Jim Hill and Dr Barry Cox in the University's School of Mathematical Sciences have developed new formulas that allow for travel beyond this limit.
Einstein's Theory of Special Relativity was published in 1905 and explains how motion and speed is always relative to the observer's frame of reference. The theory connects measurements of the same physical incident viewed from these different points in a way that depends on the relative velocity of the two observers.
"Since the introduction of special relativity there has been much speculation as to whether or not it might be possible to travel faster than the speed of light, noting that there is no substantial evidence to suggest that this is presently feasible with any existing transportation mechanisms," said Professor Hill. Read more ..
The Edge of Space
|Lee J. Siegel||October 13th 2012|
University of Utah
Using gravitational "lenses" in space, University of Utah astronomers discovered that the centers of the biggest galaxies are growing denser – evidence of repeated collisions and mergers by massive galaxies with 100 billion stars. "We found that during the last 6 billion years, the matter that makes up massive elliptical galaxies is getting more concentrated toward the centers of those galaxies. This is evidence that big galaxies are crashing into other big galaxies to make even bigger galaxies," says astronomer Adam Bolton, principal author of the new study.
"Most recent studies have indicated that these massive galaxies primarily grow by eating lots of smaller galaxies," he adds. "We're suggesting that major collisions between massive galaxies are just as important as those many small snacks."
The new study – published recently in The Astrophysical Journal – was conducted by Bolton's team from the Sloan Digital Sky Survey-III using the survey's 2.5-meter optical telescope at Apache Point, N.M., and the Earth-orbiting Hubble Space Telescope. The telescopes were used to observe and analyze 79 "gravitational lenses," which are galaxies between Earth and more distant galaxies. A lens galaxy's gravity bends light from a more distant galaxy, creating a ring or partial ring of light around the lens galaxy. Read more ..
The Edge of Space
|Sam Orez||October 12th 2012|
Space debris came into focus last week at the International Astronautical Congress in Naples, Italy. Envisat, ESA’s largest Earth observation satellite, ended its mission last spring and was a subject of major interest in the Space Debris and Legal session.
Envisat was planned and designed in 1987–1990, a time when space debris was not considered to be a serious problem and before the existence of mitigation guidelines, established by the UN in 2007 and adopted the next year by ESA for all of its projects.
Only later, during the post-launch operational phase, did Envisat’s orbit of about 780 km become a risky debris environment, particularly following the Chinese antisatellite missile test in 2007 and the collision between the Iridium and the Cosmos satellites in 2009. Lowering Envisat to an orbit that would allow reentry within 25 years, however, was never an option because of its design and limited amount of fuel. Read more ..
The Edge of Climate Change
|Michael Bishop||October 11th 2012|
Institute of Physics
The well-documented presence of excessive levels of carbon dioxide (CO2) in our atmosphere is causing global temperatures to rise and glaciers and ice caps to melt. Researchers from the Massachusetts Institute for Technology have shown that the material strength and fracture toughness of ice are decreased significantly under increasing concentrations of CO2 molecules, making ice caps and glaciers more vulnerable to cracking and splitting into pieces, as was seen recently when a huge crack in the Pine Island Glacier in Antarctica spawned a glacier the size of Berlin. Ice caps and glaciers cover seven per cent of the Earth—more than Europe and North America combined—and are responsible for reflecting 80 per cent of the Sun's light rays that enter our atmosphere and maintain the Earth's temperature. They are also a natural carbon sink, capturing a large amount of CO2.
"If ice caps and glaciers were to continue to crack and break into pieces, their surface area that is exposed to air would be significantly increased, which could lead to accelerated melting and much reduced coverage area on the Earth. The consequences of these changes remain to be explored by the experts, but they might contribute to changes of the global climate," said lead author of the study Professor Markus Buehler. Read more ..
The Edge of Space
|Eric Gershon||October 11th 2012|
New research led by Yale University scientists suggests that a rocky planet twice Earth's size orbiting a nearby star is a diamond planet.
"This is our first glimpse of a rocky world with a fundamentally different chemistry from Earth," said lead researcher Nikku Madhusudhan, a Yale postdoctoral researcher in physics and astronomy. "The surface of this planet is likely covered in graphite and diamond rather than water and granite."
The planet — called 55 Cancri e — has a radius twice Earth's, and a mass eight times greater, making it a "super-Earth." It is one of five planets orbiting a sun-like star, 55 Cancri, that is located 40 light years from Earth yet visible to the naked eye in the constellation of Cancer. The planet orbits at hyper speed — its year lasts just 18 hours, in contrast to Earth's 365 days. It is also blazingly hot, with a temperature of about 3,900 degrees Fahrenheit, researchers said, a far cry from a habitable world. Read more ..
The Edge of Climate Change
|Rosanne Skirble||October 10th 2012|
Summers in the Scandinavian Arctic are the warmest they've been in nearly 2,000 years, and this warming of the oceans worldwide could be leading to smaller fish, which has major implications for global fisheries, according to two new studies.
William D’Andrea studies how Earth’s climate changes over time. In an article just published in the journal Geology, the associate professor at Columbia University’s Lamont-Doherty Earth Observatory charts 1,800 years of Arctic climate history, based on his analysis of sediment from a lake in the Norwegian archipelago of Svalbard.
“This location hasn’t been as warm in the last 1,800 years as it has been in the last two decades,” he says. D’Andrea and his colleagues reconstructed that climate history by examining traces of algae in the organic material and minerals that settled to the Arctic lake bottom over the millennia. Read more ..
The Edge of the Universe
|Breanna Bishop||October 10th 2012|
One of the unsolved mysteries of contemporary science is how highly organized structures can emerge from the random motion of particles. This applies to many situations ranging from astrophysical objects that extend over millions of light years to the birth of life on Earth.
The surprising discovery of self-organized electromagnetic fields in counter-streaming ionized gases (also known as plasmas) will give scientists a new way to explore how order emerges from chaos in the cosmos. This breakthrough finding was published online in the journal, Nature Physics on Sept. 30.
"We've created a model for exploring how electromagnetic fields help organize ionized gas or plasma in astrophysical settings, such as in the plasma flows that emerge from young stars," said lead author Nathan Kugland, a postdoctoral researcher in the High Energy Density Science Group at Lawrence Livermore National Laboratory (LLNL). "These fields help shape the flows, and likely play a supporting role alongside gravity in the formation of solar systems, which can eventually lead to the creation of planets like the Earth." Read more ..
The Edge of Nature
|Jim Erickson||October 9th 2012|
University of Michigan
|Icebreaker Oden in Antarctica. Photo by J. Wegelius.|
An international team of scientists, including a University of Michigan graduate student, has demonstrated that a clear difference exists between the marine microbial communities in the Southern and Arctic oceans, contributing to a better understanding of the biodiversity of marine life at the poles.
The most comprehensive comparison of microbial diversity at both of Earth's polar oceans showed that about 75 percent of the organisms at each pole are different. This insight sheds light on newly recognized biodiversity patterns and reinforces the importance of studying Earth's polar regions in the face of a changing climate. And it highlights the need for further research on the impacts of sea ice, seasonal shifts and freshwater input in both regions.
"We believe that significant differences in the environmental conditions at each pole and unique selection mechanisms in the Arctic and Southern oceans are at play in controlling surface and deep-ocean community structure," said Alison Murray, leader of the international team and an associate research professor at the Desert Research Institute in Reno, Nev. Read more ..
The Edge of Nature
|Martin Barillas||October 8th 2012|
Cutting Edge Senior Correspondent
|Hiawatha National Forest in Michigan.|
Live insects were found in 47 percent of firewood bundles purchased from big box stores, gas stations and grocery stores in Colorado, New Mexico, Utah and Wyoming
A new study published in the Journal of Economic Entomology reports that live insects were found in 47 percent of firewood bundles purchased from big box stores, gas stations and grocery stores in Colorado, New Mexico, Utah and Wyoming.
According to a release from the Entomological Society of America, untreated firewood can harbor pathogens and destructive insects such as the emerald ash borer, the Asian longhorned beetle, bark beetles and others, and transport them to uninfested areas. Furthermore, the risk of moving insects in untreated firewood is high, the authors found, because insects emerged up to 558 days from the purchase date of the wood. Read more ..
The Edge of Health
|Kelly Servick||October 8th 2012|
He and his team, including Ph.D. student Krysta Biniek and postdoctoral researcher Kemal Levi, focused on the outmost layer of skin: the stratum corneum. It protects deeper layers from drying out or getting infected, and it’s also our first line of defense against UV radiation. They found that beyond the well-documented DNA damage and cancer risk, UV rays also change the way the outermost skin cells hold together and respond to strain. Read more ..
The Edge of Space
|Phil Mercer||October 7th 2012|
A powerful new super telescope in the Australian outback is set to begin probing the origins of stars and galaxies. The Australian Square Kilometer Array Pathfinder (ASKAP) lies in the western Australian desert. The technology is expected to capture radio images with unprecedented sensitivity and speed across large areas of sky.
Australian scientists say the new facility opening Friday on the country’s remote west coast will be one of the world’s most important radio telescopes. The isolated site was chosen because it is remarkably quiet, with a small population and few man-made radio signals that could interfere with the faint astronomical data.
The antenna array will give astronomers the power to investigate some fundamental questions about the universe, including dark matter, the nature of gravity and the origins of the first stars and galaxies. The super telescope is 100 times more powerful than any previous design. Read more ..
The Edge of Climate Change
|Kellen Calinger||October 6th 2012|
Warming temperatures in Ohio are a key driver behind changes in the state's landscape, and non-native plant species appear to be responding more strongly than native wildflowers to the changing climate, new research suggests. This adaptive nature demonstrated by introduced species could serve them well as the climate continues to warm. At the same time, the non-natives' potential ability to become even more invasive could threaten the survival of native species already under pressure from land-use changes, researchers say.
The research combines analyses of temperature change and blooming patterns of 141 species of Ohio wildflowers since 1895. Overall, the average temperature increased 1.7 degrees Fahrenheit (0.9 degrees Celsius) in Ohio between 1895 and 2009. And 66 wildflower species – or 46 percent of the 141 studied – flowered earlier than usual in response to that warming.
This change in flowering patterns not only alters the landscape, but affects the availability of food for insects and birds and can influence the reproductive success of the plants themselves. This kind of wildflower data is difficult to come by because historical observations of flowering trends simply don't exist in most states. Read more ..
The Edge of Climate Change
|Leane Regan||October 6th 2012|
A decline in April-May rainfall over south-east Australia is associated with a southward expansion of the subtropical dry-zone according to research published today in Scientific Reports, a primary research journal from the publishers of Nature.
CSIRO scientists Wenju Cai, Tim Cowan and Marcus Thatcher explored why autumn rainfall has been in decline across south-eastern Australia since the 1970s, a period that included the devastating Millennium drought from 1997-2009.
Previous research into what has been driving the decline in autumn rainfall across regions like southern Australia has pointed the finger at a southward shift in the storm tracks and weather systems during the late 20th century. However, the extent to which these regional rainfall reductions are attributable to the poleward expansion of the subtropical dry-zone has not been clarified before now.
Mr Cowan said rainfall patterns in the subtropics are known to be influenced by the Hadley cell, the large-scale atmospheric circulation that transports heat from the tropics to the sub-tropics. Read more ..
The Ancient Edge
|David Kelly||October 6th 2012|
A skull fragment unearthed by anthropologists in Tanzania shows that our ancient ancestors were eating meat at least 1.5 million years ago, shedding new light into the evolution of human physiology and brain development.
"Meat eating has always been considered one of the things that made us human, with the protein contributing to the growth of our brains," said Charles Musiba, Ph.D., associate professor of anthropology at the University of Colorado Denver, who helped make the discovery. "Our work shows that 1.5 million years ago we were not opportunistic meat eaters, we were actively hunting and eating meat."
The two-inch skull fragment was found at the famed Olduvai Gorge in northern Tanzania, a site that for decades has yielded numerous clues into the evolution of modern humans and is sometimes called `the cradle of mankind.' The fragment belonged to a 2-year-old child and showed signs of porotic hyperostosis associated with anemia. According to the study, the condition was likely caused by a diet suddenly lacking in meat. Read more ..
The Human Edge
|James Devitt||October 4th 2012|
New York University
Biologists from New York University have uncovered new ways our biological clock's neurons use electrical activity to help keep behavioral rhythms in order. The findings, which appear in the journal Current Biology, also point to fresh directions for exploring sleep disorders and related afflictions.
"This process helps explain how our biological clocks keep such amazingly good time," said Justin Blau, an associate professor of biology at NYU and one of the study's authors.
Blau added that the findings may offer new pathways for exploring treatments to sleep disorders because the research highlights the parts of our biological clock that "may be particularly responsive to treatment or changes at different times of the day." In a previous study, Blau and his colleagues found that rhythms in expression of a potassium channel (Ir) helps link the biological clock to the activity of pacemaker neurons. But Ir does not function as a simple output of the clock—it also feeds back to regulate the core clock. In the Current Biology research, the scientists sought to understand the nature of this feedback. Read more ..
The Edge of Nature
|Jennifer Chu||October 4th 2012|
The colorful leaves piling up in your backyard this fall can be thought of as natural stores of carbon. In the springtime, leaves soak up carbon dioxide from the atmosphere, converting the gas into organic carbon compounds. Come autumn, trees shed their leaves, leaving them to decompose in the soil as they are eaten by microbes. Over time, decaying leaves release carbon back into the atmosphere as carbon dioxide.
In fact, the natural decay of organic carbon contributes more than 90 percent of the yearly carbon dioxide released into Earth's atmosphere and oceans. Understanding the rate at which leaves decay can help scientists predict this global flux of carbon dioxide, and develop better models for climate change. But this is a thorny problem: A single leaf may undergo different rates of decay depending on a number of variables: local climate, soil, microbes and a leaf's composition. Differentiating the decay rates among various species, let alone forests, is a monumental task. Read more ..
The Digital Edge
|Abigail Klein Leichman||October 3rd 2012|
Imagine that you cannot talk. You know what you want to say, but your speaking muscles are paralyzed because of a stroke, nerve disease, or other medical condition. Technion-Israel Institute of Technology researcher Ariel Tankus does not have a magic wand to cure the problem, but the 37-year-old computer scientist has spent two years working on a complex brain-machine interface that could give the power of speech to people unable to express themselves. This advanced technology would articulate letters or words by decoding brain activity triggered by the patients thinking of the sounds they wish to make.
The beginnings of the research were recently described in the scientific journal Nature Communications by Tankus and his research partners, Prof. Shy Shoham from the Technion and Prof. Itzhak Fried of the University of California Los Angeles (UCLA), where Tankus did his postdoctoral research. Tankus relates that he has been investigating brain-machine interface possibilities since 2005. Four years later, he paired with Shoham and shifted his focus to speech—a complex and challenging area to study in the brain. Read more ..
The Water's Edge
|Boris Koch||October 2nd 2012|
Alfred Wegener Institute for Polar and Marine Research
Water does not forget, says Prof. Boris Koch, a chemist at the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association. Irrespective of what happens in the sea: whether the sun shines, algae bloom or a school of dolphins swims through a marine area – everything and everyone leaves biomolecular tracks. With the help of a combination of new techniques, Boris Koch and colleagues can now identify and retrace some of these. In a special volume of the open access journal Biogeosciences, these scientists report on how these analyses work and which events in the sea have so far been uncovered by researchers.
Ponds, peat holes and roadside ditches full of stagnant rainwater were previously of no interest to the chemist Boris Koch. “Then I thought: everyone knows this brown sludge; what could be interesting about it? Today we are working with these very substances that colour the water in roadside ditches brown – or expressed more precisely, with dissolved organic matter which not only occurs in ponds, but of course also in oceans,” says Boris Koch, who initiated the research project and is co-editor of the special volume. Read more ..
The Edge of Nature
|Sabine Guinsbourg||October 2nd 2012|
Slave rebellion is widespread in ants
Enslaved worker ants kill the offspring of their parasites and thereby improve the chances of survival for their neighboring relatives. Ants that are held as slaves in nests of other ant species damage their oppressors through acts of sabotage. Ant researcher Professor Dr. Susanne Foitzik of Johannes Gutenberg University Mainz (JGU) in Germany first observed this "slave rebellion" phenomenon in 2009. According to the latest findings, however, this behavior now appears to be a widespread characteristic that is not limited to isolated occurrences.
In fact, in three different populations in the U.S. states of West Virginia, New York, and Ohio, enslaved Temnothorax longispinosus workers have been observed to neglect and kill the offspring of their Protomognathus americanus slavemakers rather than care for them. As a result, an average of only 45 percent of the parasite's offspring survived. This presumably reduces the strength of the parasites in the area and thereby increases the chances of survival for the neighboring colonies populated by the slave ants' relatives.
More than half of all animal species live in parasitic relationships, i.e. they exploit their so-called hosts. From the perspective of evolutionary history, the American slave-making ant Protomognathus americanus is an old social parasite that is entirely dependent on other ant species for its survival. Slave workers have to care for the brood in parasite nests, bring food to their masters and feed them, and even defend the nest. Read more ..
The Edge of Materials
|Caroline McCall||October 1st 2012|
|Caryatid with cracks (credit: Kevan Davis)|
Diving into a pool from a few feet up allows you to enter the water smoothly and painlessly, but jumping from a bridge can lead to a fatal impact. The water is the same in each case, so why is the effect of hitting its surface so different? This seemingly basic question is at the heart of complex research by a team in MIT's Department of Nuclear Science and Engineering (NSE) that studied how materials react to stresses, including impacts. The findings could ultimately help explain phenomena as varied as the breakdown of concrete under sudden stress and the effects of corrosion on various metal surfaces.
Using a combination of computer modeling and experimental tests, the researchers studied one specific type of stress—in a defect called a screw dislocation—in one kind of material, an iron crystal lattice. But the underlying explanation, the researchers say, may have broad implications for many kinds of stresses in many different materials. The research, carried out by doctoral student Yue Fan, associate professor Bilge Yildiz, and professor emeritus Sidney Yip, is being published this week in the journal Physical Review Letters.
Essentially, the team analyzed how the strength of a material can increase quite abruptly as the rate of strain applied to the material increases. This transition in the rate at which a material cracks or bends, called a flow-stress upturn, has been observed experimentally for many years, but its underlying mechanism has never been fully explained, the researchers say. Read more ..
The Laser Edge
|Julien Happich||October 1st 2012|
Scientists from Cambridge University (UK) have developed a process to print lasers using everyday inkjet technology, which could be used to form lasers on virtually any surface, rigid or flexible, and which could be potentially be applied using existing printing and publishing equipment.
Today, most lasers are made on silicon wafers using expensive processes similar to those used to make microprocessors. However, scientists have now designed a process to "print" a type of organic laser on any surface, using technology very similar to that used in the home. The process involves developing lasers based on chiral nematic liquid crystals (LCs), similar to the materials used in flat-panel LCD displays. These are a unique class of photonic materials that, under the right conditions, can be stimulated to produce laser emissions. If aligned properly, the helix-shaped structure of the LC molecules can act as an optically resonant cavity - an essential component of any laser. After adding a fluorescent dye, the cavity can then be optically excited to produce laser light. Read more ..
The Edge of Physics
|Megan Fellman||September 29th 2012|
An interdisciplinary team of researchers from Northwestern University, the University of Illinois at Urbana-Champaign and Tufts University are the first to demonstrate "transient electronics" -- which are electronics that gradually disappear on a specified schedule, whether it be a few days or six months.
These kinds of electronics could have applications in medicine, pharmaceuticals, environmental monitors and the military, among other uses.
Conventional electronics are made to last indefinitely. Transient electronics, on the other hand, offer the opposite behavior. They physically vanish over time in a well-controlled manner and at a prescribed time, dissolving when they react with water. A magnesium oxide encapsulation layer and silk overcoat envelops the electronics, and the thickness determines how long the system will take to disappear into its environment.
"These electronics are there when you need them, and after they've served their purpose they disappear," said Yonggang Huang, who led the Northwestern portion of the research focused on theory, design and modeling. "This is a completely new concept."
The novel technology opens up important possibilities. Transient electronics could be useful as medical devices implanted inside the human body to monitor such things as temperature or brain, heart and muscle tissue activity, to apply thermal therapy or to deliver drugs. When no longer needed, the electronics would be fully absorbed by the body with no adverse effects. (Implantable electronics are not commonly used in medicine because of concern about the long-term effects.) Such a system also could be used as environmental monitors placed on buildings, roadways or military equipment to detect temperature change or structural deformation. The device would dissolve when exposed to water, eliminating the need for it to be recovered at a future date. Read more ..
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