|Laura Bailey||December 6th 2010|
Young people who are overexposed to antibacterial soaps containing triclosan may suffer more allergies, and exposure to higher levels of Bisphenol A among adults may negatively influence the immune system, a new University of Michigan School of Public Health study suggests. The paper is titled, “The Impact of Bisphenol A and Triclosan on Immune Parameters in the U.S. Population.”
Triclosan is a chemical compound widely used in products such as antibacterial soaps, toothpaste, pens, diaper bags and medical devices. Bisphenol A (BPA) is found in many plastics and, for example, as a protective lining in food cans. Both of these chemicals are in a class of environmental toxicants called endocrine-disrupting compounds (EDCs), which are believed to negatively impact human health by mimicking or affecting hormones. Read more ..
Edge on Environment
|Nicole Casal-Moore||December 6th 2010|
|Edge of Antarctic glacier calves into the sea|
In an effort to understand how fast sea level could rise as the climate warms, a University of Michigan researcher has developed a new theory to describe how icebergs detach from ice sheets and glaciers. This process of "iceberg calving" isn't well understood.
While scientists believe it currently accounts for roughly half of the mass lost in shrinking ice sheets, current sea level rise models don't take changes in iceberg calving into account in their predictions, says Jeremy Bassis, an assistant professor in the Department of Atmospheric, Oceanic and Space Sciences at the institution based in Ann Arbor MI. "Our models cannot predict about half of the mass balance. We don't know how much of an effect this will have, but we've seen several prominent examples where calving is connected with speed-up of the ice-retreat process," Bassis said. The Larsen B ice shelf in Antarctica—a 2,000-square-mile, 700-foot-thick slab that had been stable for thousands of years—disintegrated in about six weeks between January and March of 2002. Read more ..
The Edge of Space
|Kim Thurler||November 29th 2010|
Some of the universe's most massive galaxies may have formed billions of years earlier than current scientific models predict, according to surprising new research led by Tufts University. "We have found a relatively large number of very massive, highly luminous galaxies that existed almost 12 billion years ago when the universe was still very young, about 1.5 billion years old. These results appear to disagree with the latest predictions from models of galaxy formation and evolution," said Tufts astrophysicist Danilo Marchesini, assistant professor of physics and astronomy at the Tufts School of Arts and Sciences. "Current understanding of the physical processes responsible in forming such massive galaxies has difficulty reproducing these observations." Read more ..
China on the Edge
|Sara Jerome||November 29th 2010|
The massive hacking Google faced in China, first revealed in January, may have been an attack by Chinese government operatives, according to information revealed by Wikileaks.
Among the the more than 200,000 documents released by Wikileaks, one suggests a connection between the Chinese government and the Google hacking, which led the company to threaten to pull its operations from China.
The New York Times, in its coverage of the Wikileaks documents, reports that China’s Politburo may have directed the hacking. A Chinese contact who spoke with the American Embassy said as much in Beijing in January, one cable reveals. Read more ..
The Genetic Edge
|Martin Barillas||November 22nd 2010|
Cutting Edge Senior Contributor
|Medieval map showing the Old World and American coastline|
When Christopher Columbus returned from his first voyage to the Americas, he shanghaied ten to twenty-five of the native peoples he encountered on the Caribbean islands he explored. Of these, only 6 were to be presented to the court of Spain's Catholic monarchs when he returned to the Iberian Peninsula in March 1493. These 6 American natives were presumed to be the first of the New World to set foot in the Old World. Until now.
King Ferndinand of Aragon and Isabella of Castille had joined forces to unite Spain as the first modern nation-state, and by bankrolling Columbus they set about on a process of conquest, exchange, and transformation that still resonates today. Read more ..
Edge on Medicine
|Nancy Ross-Flanigan||November 22nd 2010|
Strategies for preventing the spread of whooping cough—on the rise in the United States and several other countries in recent years—should take into account how often people in different age groups interact, research at the University of Michigan suggests.
Thanks to widespread childhood vaccination, whooping cough (pertussis) once seemed to be under control. But the illness, which in infants causes violent, gasping coughing spells, has made a comeback in some developed countries since the 1980s, becoming a major public health concern. Read more ..
Edge of Space
|Michael Byers||November 22nd 2010|
In September 2010, a group of astronomers at the Lick-Carnegie Exoplanet Survey announced the discovery of the first so-called “Goldilocks planet.” Gliese 581g (also dubbed “Zarmina's World” by its discoverer, UC Santa Cruz astronomer Steven Vogt, who has romantically named the planet after his wife) is the first rocky planet outside our solar system known to be situated “just right” for life—that is, within the habitable zone of its star.
While its possibilities for harboring life have attracted new attention to the continuing search for other worlds, Gliese 581g is just one of hundreds of exoplanets located during the last few years. More than 20 light years from Earth, its discovery calls to mind the amazing story behind the discovery in 1930 of what was, for a time, the most distant known planet—Pluto. This year is the 80th anniversary of Pluto’s discovery, and it's fair to say that the pace of discovery is, to say the least, accelerating.
The six planets in outward progress from the sun—Mercury, Venus, Earth (naturally), Mars, Jupiter, and Saturn—have been known from antiquity. The seventh planet, Uranus, was accidentally discovered in 1781 by William Herschel, who, over the course of a few days in March of that year, observed an object moving steadily against the unmoving background stars. Herschel initially reported his finding as a comet, but by 1783 his and others’ observations had confirmed the planetary nature of Uranus. This revolutionary discovery greatly expanded the understood size of the Solar System, and suggested that more worlds might remain to be found. Read more ..
|Laura Bailey||November 15th 2010|
A paralyzed patient may someday be able to “think” a foot into flexing or a leg into moving, using technology that harnesses the power of electricity in the brain, and scientists at University of Michigan School of Kinesiology are now one big step closer.
Researchers at the school and colleagues from the Swartz Center for Computational Neuroscience at the University of California, San Diego have developed technology that for the first time allows doctors and scientists to noninvasively isolate and measure electrical brain activity in moving people.
This technology is a key component of the kind of brain-computer interfaces that would allow a robotic exoskeleton controlled by a patient’s thoughts to move that patient's limb, said Daniel Ferris, associate professor in the School of Kinesiology and author of a trio of papers detailing the research.
“Of course that is not going to happen soon but a step toward being able to do that is the ability to record brain waves while somebody is moving around,” said Joe Gwin, first author on the papers and a graduate research fellow in the School of Kinesiology and the Department of Mechanical Engineering. Read more ..
Edge on Environment
|Cheryl Dybas||November 15th 2010|
|NASA image of Lake Titicaca|
Catastrophic drought is on the near-term horizon for the capital city of Bolivia, according to new research into the historical ecology of the Andes.
If temperatures rise more than 1.5 to 2 degrees Celsius (3 to 5 degrees Fahrenheit) above those of modern times, parts of Peru and Bolivia will become a desert-like setting.
The change would be disastrous for the water supply and agricultural capacity of the two million inhabitants of La Paz, Bolivia's capital city, scientists say.
The results, derived from research funded by the National Science Foundation (NSF) and conducted by scientists affiliated with the Florida Institute of Technology (FIT), appear in the November issue of the journal Global Change Biology.
Climatologist Mark Bush of FIT led a research team investigating a 370,000-year record of climate and vegetation change in Andean ecosystems.
The scientists used fossilized pollen trapped in the sediments of Lake Titicaca, which sits on the border of Peru and Bolivia.
They found that during two of the last three interglacial periods, which occurred between 130,000-115,0000 years ago and 330,000-320,000 years ago, Lake Titicaca shrank by as much as 85 percent.
Adjacent shrubby grasslands were replaced by desert.
In each case, a steady warming occurred that caused trees to migrate upslope, just as they are doing today. Read more ..
The Edge of Space
|Sarah Stewart||November 8th 2010|
Our sun sporadically expels trillions of tons of million-degree hydrogen gas in explosions called coronal mass ejections (CMEs). Such clouds are enormous in size (spanning millions of miles) and are made up of magnetized plasma gases, so hot that hydrogen atoms are ionized. CMEs are rapidly accelerated by magnetic forces to speeds of hundreds of kilometers per second to upwards of 2,000 kilometers per second in several tens of minutes. CMEs are closely related to solar flares and, when they impinge on the Earth, can trigger spectacular auroral displays. Read more ..
The Ancient Edge
|Diego DiGhero||November 1st 2010|
Research conducted on papyri sheds light on an ancient world with surprisingly modern concerns: including hoped-for medical cures, religious confusion and the need for financial safeguards. The field of study known as papyrology is the study of texts on papyrus and other materials, mainly from ancient Egypt and from the period of Greek and Roman rule. Both Biblical and Classical scholars avidly study scrolls written on papyrus to reveal answers to questions about ancient texts. The recent research revealed fascinating details about daily life, including banking and the charging of interest on loans. Read more ..
|Tessa Muggeridge and Charlie Litton||November 1st 2010|
A sleep-deprived person behind the wheel or in the cockpit is just as dangerous as a drunken driver.
That’s one of the conclusions scientists have reached after years of study on the need for sleep—and what happens when people don’t get enough of it.
Scientific understanding of sleep has improved dramatically over the past 20 years with a surge of research on everything from sleep apnea and internal body clocks to the reaction times and judgments of those who are sleep-deprived. But U.S. transportation guidelines lag far behind the research.
The regulations are outdated across all sectors of transportation. Current flight-time restrictions for airline pilots haven’t significantly changed since the 1930s, although they are currently under review. Regulations governing truck and bus drivers were only recently updated, and those changes might be temporary due to legal challenges. And the U.S. Coast Guard has failed to act on at least six NTSB recommendations that date back as far as 1978 to revise hours-of-service regulations for commercial boaters.
Jim Hall, former chair of the NTSB, said it’s shocking that U.S. agencies that oversee air, rail, water and highway safety all have failed to take scientific evidence about “the limits on performance and the rest requirements for human beings and put that into the regulations.” Read more ..
|Diego DiGhero||October 27th 2010|
|Potomac River smallmouth bass|
New research has provided the first evidence that “gender bending” chemicals which find their way from human products into rivers and oceans can have a significant impact on the ability of fish to breed in rivers of the United Kingdom. The findings from the four year study, led by the universities of Exeter and Brunel, has important implications for understanding the impacts of these chemicals on ecosystem health and possibly on humans. They appear to bolster similar evidence found in watersheds of the United States.
Endocrine disrupting chemicals (EDCs) disrupt the ways that hormones work in the bodies of vertebrates (animals with backbones), including humans. Read more ..
The Ancient Edge
|Diego DiGhero||October 26th 2010|
The pre-Columbian American societies that once lived in the Amazon rainforests may have been much larger and more advanced than researchers previously realized. Brazilian and Swedish archaeologists have found the remains of approximately 90 settlements in an area South of the city of Santarém, in the Brazilian part of the Amazon.
"The most surprising thing is that many of these settlements are a long way from rivers, and are located in rainforest areas that extremely sparsely populated today," said Per Stenborg from the Department of Historical Studies of the University of Gothenburg , who led the Swedish part of the archaeological investigations in the area over the summer. He was accompanied by Brazilians Denise Schaan and and Marcio Amaral-Lima. Read more ..
The Earth on Edge
|Kathy Svitil||October 11th 2010|
|Cross section of Pacific Ocean showing plate boundaries|
Computational scientists and geophysicists at the University of Texas at Austin and the California Institute of Technology (Caltech) have developed new computer algorithms that for the first time allow for the simultaneous modeling of the earth's Earth's mantle flow, large-scale tectonic plate motions, and the behavior of individual fault zones, to produce an unprecedented view of plate tectonics and the forces that drive it. Read more ..
Weather on the Edge
|Mary Beckman||October 4th 2010|
Like shifting sand dunes, some clouds disappear in one place and reappear in another. New work this week in Nature shows why: Rain causes air to move vertically, which breaks down and builds up cloud walls. The air movement forms patterns in low clouds that remain cohesive structures even while appearing to shift about the sky, due to a principle called self-organization.
These clouds, called open-cell clouds that look like honeycombs, cover much of the open ocean. Understanding how their patterns evolve will eventually help scientists build better models for predicting climate change. This is the first time researchers have shown the patterns cycle regularly and why. Read more ..
The Toxic Edge
|John Solomon ||September 27th 2010|
Center for Public Integrity
The number of “dead zones” in U.S. coastal waters — where oxygen is so depleted that it can harm marine life — has soared 30-fold over the last half century, according to a new White House report that warns the phenomenon poses both economic and environmental hazards.
The report by a task force of federal, state and private scientists assembled by the White House said the rise of hypoxia in ocean waters can be traced mostly to pollution, such as wastewater and fertilizer runoff. The nutrient-rich pollutants fuel blooms of algae and other bacteria that suck oxygen out of the water, the researchers said. Read more ..
Agriculture on the Edge
|Nancy Ross-Flanigan ||September 20th 2010|
Proponents of organic farming often speak of nature's balance in ways that sound almost spiritual, prompting criticism that their views are unscientific and naïve. At the other end of the spectrum are those who see farms as battlefields where insect pests and plant diseases must be vanquished with the magic bullets of modern agriculture: pesticides, fungicides and the like.
Which view is more accurate? A 10-year study of an organic coffee farm in Mexico suggests that, far from being romanticized hooey, the "balance and harmony" view is on the mark. Ecologists John Vandermeer and Ivette Perfecto of the University of Michigan and Stacy Philpott of the University of Toledo have uncovered a web of intricate interactions that buffers the farm against extreme outbreaks of pests and diseases, making magic bullets unnecessary. Read more ..
Edge on Terror
|Scott Stewart and Nate Hughes||September 13th 2010|
Over the past decade there has been an ongoing debate over the threat posed by electromagnetic pulse (EMP) to modern civilization. This debate has been the most heated perhaps in the United States, where the commission appointed by Congress to assess the threat to the United States warned of the dangers posed by EMP in reports released in 2004 and 2008. The commission also called for a national commitment to address the EMP threat by hardening the national infrastructure.
There is little doubt that efforts by the United States to harden infrastructure against EMP — and its ability to manage critical infrastructure manually in the event of an EMP attack — have been eroded in recent decades as the Cold War ended and the threat of nuclear conflict with Russia lessened. This is also true of the U.S. military, which has spent little time contemplating such scenarios in the years since the fall of the Soviet Union. Read more ..
The Ancient World
|Iken Paap||September 13th 2010|
Since 2009, researchers from Germany and Mexico have been systematically uncovering and mapping the old walls of Uxul, a Mayan city. In the process, researchers including Dr. Nikolai Grube of the University of Bonn and Mexican archaeologist Antonio Benavides Castillo came across two water reservoirs of approximately 100 yards square.
Such monster pools, which are also known from other Mayan cities, are called “aguadas. Similar to present-day water towers, they served to store drinking water. But the people of Uxul seem to have thought of a particularly smart way to seal their aguada. “We conducted a trial dig in the center of one of the water reservoirsm explains Nicolaus Seefeld, a young scholar. “We found that the bottom, which is at a depth of two meters, was covered with ceramic shards—probably from plates—practically without any gaps. But we don't know yet whether it's like this throughout the entire aguada. Read more ..
Edge on the Universe
|Steve Koppes||September 6th 2010|
This month physicist Juan Collar and his associates are taking their attempt to unmask the secret identity of dark matter into a Canadian mine more than a mile underground.
The team is deploying a 4-kilogram bubble chamber at SNOLab, which is part of the Sudbury Neutrino Observatory in Ontario, Canada. A second 60-kilogram chamber will follow later this year. Scientists anticipate that dark matter particles will leave bubbles in their tracks when passing through the liquid in one of these chambers. Dark matter accounts for nearly 90 percent of all matter in the universe. Although invisible to telescopes, scientists can observe the gravitational influence that dark matter exerts over galaxies. Read more ..
Edge of Climate Change
|Jessica Robertson ||August 30th 2010|
Many of Asia’s glaciers are retreating as a result of climate change.
This retreat impacts water supplies to millions of people, increases the likelihood of outburst floods that threaten life and property in nearby areas, and contributes to sea-level rise.
The U.S. Geological Survey, in collaboration with 39 international scientists, published a report on the status of glaciers throughout all of Asia, including Russia, China, India, Nepal, Bhutan, Pakistan, Afghanistan, Georgia, Kyrgyzstan, Tajikistan, and Kazakhstan.
“Of particular interest are the Himalaya, where glacier behavior impacts the quality of life of tens of millions of people,” said USGS scientist Jane Ferrigno. “Glaciers in the Himalaya are a major source of fresh water and supply meltwater to all of the rivers in northern India.” Read more ..
The Mind's Edge
|William Hathaway||August 23rd 2010|
Researchers at Yale University in New Haven, Connecticut, have discovered how a novel anti-depressant can take effect in hours, rather than the weeks or months usually required for most drugs currently on the market. The findings should speed development of a safe and easy-to-administer form of the anti-depressant ketamine, which has already proven remarkably effective in treating severely depressed patients.
The Yale scientists found that, in rats, ketamine not only quickly improves depression-like behaviors but actually restores connections between brain cells damaged by chronic stress.
"It's like a magic drug—one dose can work rapidly and last for seven to 10 days," said Ronald Duman, professor of psychiatry and pharmacology at Yale and senior author of the study.
Ketamine traditionally has been used as a general anesthetic for children, but a decade ago researchers at the Connecticut Mental Health Center found that, in lower doses, the drug seemed to give patients relief from depression, Duman said. In these initial clinical studies, which have been replicated at the National Institute of Mental Health, almost 70 percent of patients who are resistant to treatment with all other forms of antidepressants were found to improve within hours after receiving ketamine. Read more ..
Edge on Biofuel
When it comes to selecting the right plant source for future cellulosic biofuel production, the solution won't be one-size-fits-all, and it certainly doesn't have to involve food and feed crops.
Researchers from the Energy Biosciences Institute produced a report that suggests that a diversity of plant species, adaptable to the climate and soil conditions of specific regions of the world, can be used to develop agroecosystems for fuel production that are compatible with contemporary environmental goals.
EBI Director Chris Somerville of the University of California, Berkeley, and Deputy Director Steve Long of the University of Illinois at Urbana-Champaign were co-authors with EBI bioenergy analysts. EBI is a collaboration of UC Berkeley, the University of Illinois, Lawrence Berkeley National Laboratory, and the funding sponsor BP.
Their article, "Feedstocks for Lignocellulosic Biofuels," discusses the sustainability of current and future crops that may be used to produce advanced biofuels with emerging technologies that use non-edible parts of plants. Such crops include perennial grasses like Miscanthus grown in the rain-fed areas of the U.S. Midwest, East and South; sugarcane in Brazil and other tropical regions, including the southeastern U.S.; Agave in semiarid regions such as Mexico and the U.S. Southwest; and woody biomass from various sources. Read more ..
Edge on Security
|Pat Vaughan Tremmel ||August 9th 2010|
Imagine technology that allows you to get inside the mind of a terrorist to know how, when and where the next attack will occur.
That's not nearly as far-fetched as it seems, according to a new Northwestern University study.
Say, for purposes of illustration, that the chatter about an imminent terrorist attack is mounting, and specifics about the plan emerge, about weapons that will be used, the date of such a dreaded event and its location.
If the new test used by the Northwestern researchers had been used in such a real-world situation with the same type of outcome that occurred in the lab, the study suggests, culpability extracted from the chatter could be confirmed.
In other words, if the test conducted in the Northwestern lab ultimately is employed for such real-world scenarios, the research suggests, law enforcement officials ultimately may be able to confirm details about an attack - date, location, weapon -- that emerges from terrorist chatter. Read more ..
Edge of Space
Conditions favourable to life may once have existed all over Mars. Detailed studies of minerals found inside craters show that liquid water was widespread, not only in the southern highlands, but also beneath the northern plains.
ESA’s Mars Express and NASA’s Mars Reconnaissance Orbiter have discovered hydrated silicate minerals in the northern lowlands of Mars, a clear indication that water once flowed there.
The spacecraft have previously discovered thousands of small outcrops in the southern hemisphere where rock minerals have been altered by water. Many of these exist in the form of hydrated clay minerals known as phyllosilicates, and indicate that the planet’s southern hemisphere was once much warmer and wetter than it is today. Read more ..
The Ancient Edge
|Jamie Hanlon||July 26th 2010|
The body was found in a small, graffiti-stained tunnel. Robbery was likely not the motive, as his possessions and cash were found with him.
The University of Alberta's Sandra Garvie-Lok can't tell exactly how the victim on her table died, but she has a good idea. Given the visible previous cranial trauma on the body, the events that took place around the time of the murder and the location where his remains were found, she is willing to bet that this John Doe was murdered. Yet, no suspect will ever be tried or convicted for the crime. And she's OK with that.
That's because Garvie-Lok is an anthropologist, and her "victim" died almost 1,500 years ago in the ancient Greek city of Nemea during the Slavic invasion of Greece. Garvie-Lok, whose findings on her deceased subject were recently published in the International Journal of Historical Archaeology, suggests the victim was likely an eyewitness to Slavic invasion of Nemea. The deceased possibly used the tunnel entrance as an escape from the invaders, where he died/was killed.
"The Slavs and Avars (another group of eastern European peoples) were pretty brutal," said Garvie-Lok, a professor in the department of anthropology. "If he was hiding in that unpleasant place, he was probably in a lot of danger. So, he hid out, but he didn't make it."
A specialist in osteology—a field of anthropology that studies bones—Garvie-Lok was called in to the site to try to determine how the subject died. However, aside from the damage to the skull, which Garvie-Lok says are not related to the fatal injury that caused his death, there are no markings on the bones that would give her a definitive idea of the circumstances of the victim's final hours or days. Read more ..
Edge of the Universe
|Leighton Kitson||July 19th 2010|
Many of the Milky Way's ancient stars are remnants of other smaller galaxies torn apart by violent galactic collisions around five billion years ago, according to researchers at Durham University.
Scientists at Durham's Institute for Computational Cosmology and their collaborators at the Max Planck Institute for Astrophysics, in Germany, and Groningen University, in Holland, ran huge computer simulations to recreate the beginnings of our galaxy.
The simulations revealed that the ancient stars, found in a stellar halo of debris surrounding the Milky Way, had been ripped from smaller galaxies by the gravity generated by colliding galaxies.
The research, funded in the UK by the STFC, appears in the Monthly Notices of the Royal Astronomical Society. Lead author Andrew Cooper, from Durham University's Institute for Computational Cosmology, said: "Effectively we became galactic archaeologists, hunting out the likely sites where ancient stars could be scattered around the galaxy.
"Our simulations show how different relics in the galaxy today, like these ancient stars, are related to events in the distant past. Read more ..
The Ancient Edge
|Aida Gomez Robles||July 12th 2010|
The separation of Neanderthal and Homo Sapiens might have occurred at least one million years ago, more than 500,000 years earlier than previously believed after DNA-based analyses. A doctoral thesis conducted at the National Center for Research on Human Evolution (Centro Nacional de Investigación sobre la Evolución Humana) -associated with the University of Granada-, analyzed the teeth of almost all species of hominids that have existed during the past 4 million years. Quantitative methods were employed and they managed to identify Neanderthal features in ancient European populations.
The main purpose of this research –whose author is Aida Gómez Robles- was to reconstruct the history of evolution of Human species using the information provided by the teeth, which are the most numerous and best preserved remains of the fossil record. To this purpose, a large sample of dental fossils from different sites in Africa, Asia and Europe was analyzed. The morphological differences of each dental class was assessed and the ability of each tooth to identify the species to which its owner belonged was analyzed. Read more ..
The Edge of Space
The first experimental evidence showing how atmospheric nitrogen can be incorporated into organic macromolecules is being reported by a University of Arizona team.
The finding indicates what organic molecules might be found on Titan, the moon of Saturn that scientists think is a model for the chemistry of pre-life Earth.
Earth and Titan are the only known planetary-sized bodies that have thick, predominantly nitrogen atmospheres, said Hiroshi Imanaka, who conducted the research while a member of UA's chemistry and biochemistry department. Read more ..
|Cheryl Dybas||June 28th 2010|
National Science Foundation
Millions of years ago, volcanic eruptions in North America were more explosive and may have significantly affected the environment and the global climate. So scientists report in this week's issue of the journal Nature.
The researchers found the remains--deposited in layers of rocks--of eruptions of volcanoes located on North America's northern high plains that spewed massive amounts of sulfate aerosols into the atmosphere 40 million years ago. The scientists conducted their research at Scotts Bluff National Monument, Neb., and in surrounding areas.
"Combining measurements of the sulfate in ancient volcanic ash beds with a detailed atmospheric chemistry model, we found that the long-ago chemistry of volcanic sulfate gases is distinct from that of more modern times," says Huiming Bao, a geologist at Louisiana State University and lead author of the paper.
"This is the first example showing that the history of massive volcanic sulfate emissions, and their associated atmospheric conditions in the geologic past, may be retrieved from rock records." Read more ..
Edge of Climate Change
|Rob Mackay-Wood||June 21st 2010|
Global Change Institute
The first comprehensive synthesis on the effects of climate change on the world's oceans has found they are now changing at a rate not seen for several million years.
Scientists have now concluded that the growing atmospheric concentrations of man-made greenhouse gases are driving irreversible and dramatic changes to the way the ocean functions, with potentially dire impacts for hundreds of millions of people across the planet.
The findings of a report entitled The impact of climate change on the world's marine ecosystems emerged from a synthesis of recent research on the world's oceans, carried out by two of the world's leading marine scientists, one from The University of Queensland in Australia, and one from The University of North Carolina at Chapel Hill, in the USA. Read more ..
Edge of Outer Space
|Norbert Schartel||June 14th 2010|
New evidence from NASA's Chandra X-ray Observatory and ESA's XMM-Newton strengthens the case that two mid-sized black holes exist close to the center of a nearby starburst galaxy. These "survivor" black holes avoided falling into the center of the galaxy and could be examples of the seeds required for the growth of supermassive black holes in galaxies, including the one in the Milky Way.
For several decades, scientists have had strong evidence for two distinct classes of black hole: the stellar-mass variety with masses about ten times that of the Sun, and the supermassive ones, located at the center of galaxies, that range from hundreds of thousands to billions of solar masses.
But a mystery has remained: what about black holes that are in between?
Evidence for these objects has remained controversial, and until now there were no strong claims of more than one such black hole in a single galaxy. Recently, a team of researchers has found signatures in X-ray data of two mid-sized black holes in the starburst galaxy M82 located 12 million light years from Earth.
"This is the first time that good evidence for two mid-sized black holes has been found in one galaxy," said Hua Feng of the Tsinghua University in China, who led two papers describing the results. "Their location near the center of the galaxy might provide clues about the origin of the Universe's largest black holes – supermassive black holes found in the centers of most galaxies." Read more ..
Edge on Architecture
|Michael Bernstein||June 7th 2010|
Scientists have discovered the secret behind an ancient Chinese super-strong mortar made from sticky rice, the delicious "sweet rice" that is a modern mainstay in Asian dishes. They also concluded that the mortar --a paste used to bind and fill gaps between bricks, stone blocks and other construction materials remains the best available material for restoring ancient buildings.
According to the American Chemical Society, Bingjian Zhang, Ph.D., and colleagues found that construction workers in ancient China developed sticky rice mortar about 1,500 years ago by mixing sticky rice soup with the standard mortar ingredient. That ingredient is slaked lime, limestone that has been calcined, or heated to a high temperature, and then exposed to water. Sticky rice mortar probably was the world's first composite mortar, made with both organic and inorganic materials. Read more ..
The Edge of Climate Change
|Louis Bergeron||May 31st 2010|
The balance of biodiversity within North American small-mammal communities is so out of whack from the last episode of global warming about 12,000 years ago that the current climate change could push them past a tipping point, with repercussions up and down the food chain, say Stanford biologists. The evidence lies in fossils spanning the last 20,000 years that the researchers excavated from a cave in Northern California.
What they found is that although the small mammals in the area suffered no extinctions as a result of the warming that occurred at the end of the Pleistocene epoch, populations of most species nonetheless experienced a significant loss of numbers while one highly adaptable species – the deer mouse – thrived on the disruptions to the environment triggered by the changing climate.
"If we only focus on extinction, we are not getting the whole story," said Jessica Blois, lead author of a paper detailing the study to be published online by Nature on May 23. "There was a 30 percent decline in biodiversity due to other types of changes in the small-mammal community."
Read more ..
The Edge of Space
|Whitney Holmes||May 24th 2010|
Asteroids may not be the dark, dry, lifeless chunks of rock scientists have long thought.
Josh Emery, research assistant professor with the earth and planetary sciences department at the University of Tennessee, Knoxville, has found evidence of water ice and organic material on the asteroid 24 Themis. This evidence supports the idea that asteroids could be responsible for bringing water and organic material to Earth.
Using NASA's Infrared Telescope Facility on Hawaii's Mauna Kea, Emery and Andrew Rivkin of Johns Hopkins University in Laurel, Md., examined the surface of 24 Themis, a 200-kilometer wide asteroid that sits halfway between Mars and Jupiter. By measuring the spectrum of infrared sunlight reflected by the object, the researchers found the spectrum consistent with frozen water and determined that 24 Themis is coated with a thin film of ice. They also detected organic material.
"The organics we detected appear to be complex, long-chained molecules. Raining down on a barren Earth in meteorites, these could have given a big kick-start to the development of life," Emery said. Read more ..
Edge of Science
Voice of America
Back in 2005, when Frank Ruhli was trying to figure out how ancient Egypt's famous boy pharaoh, King Tut, died, he used CT scans of Tut's mummified remains. Now, says the renowned mummy expert, the new technology to screen some airline passengers for explosives can provide even more information.
"By applying this technology on top of another technology, it may help you to look differently at the specimen," he explains, adding that the Terahertz imaging - also known as "full body scan" technology - does not use any sort of radiation, which could destroy DNA remnants of the mummies.
"And finally, by using this Terahertz imaging, you eventually may be able to look at the substances within the mummy, for example, the embalming liquid used in the Egyptian way of embalming. There you can actually do sort of substance analysis which you can't really do by conventional x-ray." Read more ..
The Edge of Oil
With millions of gallons crude oil being spewed into the Gulf of Mexico from the Deepwater Horizon oil spill, the focus now is on shutting down the leak. However, in the cleanup efforts to come, “extreme caution” must be exercised so as not to make a bad situation even worse, says a leading bioremediation expert with the Lawrence Berkeley National Laboratory (Berkeley Lab).
“The concentration of detergents and other chemicals used to clean up sites contaminated by oil spills can cause environmental nightmares of their own,” says Terry Hazen, a microbial ecologist in Berkeley Lab's Earth Sciences Division who has studied such notorious oil-spill sites as the Exxon Valdez spill into Alaska's Prince William Sound. Read more ..
The Geologic Edge
|Nancy Ross-Flanigan||May 3rd 2010|
|Mt. Aconcagua in Argentina|
Trailing like a serpent’s spine along the western coast of South America, the Andes are the world’s longest continental mountain range and the highest range outside Asia, with an average elevation of 13,000 feet.
The question of how quickly the mountains attained such heights has been a contentious one in geological circles, with some researchers claiming the central Andes rose abruptly to nearly their current height and others maintaining the uplift was a more gradual process.
New research by University of Michigan paleoclimatologist Christopher Poulsen and colleagues suggests that the quick-rise view is based on misinterpreted evidence. What some geologists interpret as signs of an abrupt rise are actually indications of ancient climate change, the researchers say. The confusion results when ratios of oxygen’s two main isotopes, oxygen-18 and oxygen-16, are used to estimate past elevation, said Poulsen, an associate professor with appointments in the UM departments of Geological Sciences and Atmospheric, Oceanic, and Space Sciences. Read more ..
On the Edge of the Universe
|Francis Reddy||April 26th 2010|
If our eyes could see radio waves, the nearby galaxy Centaurus A (Cen A) would be one of the biggest and brightest objects in the sky, nearly 20 times the apparent size of a full moon. What we can't see when looking at the galaxy in visible light is that it lies nestled between a pair of giant radio-emitting gas plumes ejected by its supersized black hole. Each plume is nearly a million light-years long.
NASA's Fermi Gamma-Ray Space Telescope maps gamma rays, radiation that typically packs 100 billion times the energy of radio waves. Nevertheless, and to the surprise of many astrophysicists, Cen A's plumes show up clearly in the satellite's first 10 months of data. The study appears in the most recent edition of Science Express.
"This is something we've never seen before in gamma rays," said Teddy Cheung, a Fermi team member at the Naval Research Laboratory in Washington. "Not only do we see the extended radio lobes, but their gamma-ray output is more than ten times greater than their radio output." If gamma-ray telescopes had matured before their radio counterparts, astronomers would have instead classified Cen A as a "gamma-ray galaxy."
Also known as NGC 5128, Cen A is located about 12 million light-years away in the constellation Centaurus and is one of the first celestial radio sources identified with a galaxy. "A hallmark of radio galaxies is the presence of huge, double-lobed radio-emitting structures around otherwise normal-looking elliptical galaxies," said Jürgen Knödlseder, a Fermi collaborator at the Center for the Study of Space Radiation in Toulouse, France. "Cen A is a textbook example."
Read more ..
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