from Science News
WASHINGTON, D.C. -- Astronomers have for the first time traced gamma rays, the most energetic form of light, to galaxies undergoing a frenzy of star birth. The finding, which has revealed a new class of galactic gamma-ray sources, is not unexpected. But it provides new hints about the origin of many cosmic rays, the high-speed protons and other charged particles of extraordinarily high energies that bombard Earth.
According to the prevailing theory, cosmic rays are accelerated to energies of billions to trillions of electron volts by the expanding shock waves generated when massive stars explode as supernovas. (Cosmic rays with even higher energies are thought to be powered by supermassive black holes at the centers of galaxies.)
Kinks in a galaxy's magnetic field keep the particles, mainly protons and other charged particles, bouncing back and forth like ping-pong balls between the advancing shock wave and the region just in front of it, revving up the particles to these high energies, the model suggests.
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from the Economist
One of the most enduring urban myths is how the patent for an ever-lasting light bulb pioneered by a lone inventor was snapped up by a cartel of lighting manufacturers, who promptly secreted it away to protect their hugely profitable replacement business.
The fact is, lots of long-life bulbs have been invented over the years since Thomas Edison borrowed the best from the dozen or so different light-bulb designs patented during the early days of electrification and came up with a winner. Practically all the improvements in terms of life and brightness since then have come from the bulb-makers themselves. One of the most recent was Philips's incandescent light bulb that lasts for 60,000 hours.
As standalone products, though, few of the new designs have been able to compete--in terms of the inevitable trade-off between performance and price demanded by the marketplace--with the 1,000 hours or so of the tungsten-filament incandescent bulb. Most new bulb designs have either been relegated to specific roles or incorporated into mainstream products. But that all changed when the "twistie" or CFL (compact fluorescent lamp) arrived on the scene a decade ago.
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from Technology Review
Last month Danish wind turbine company Vestas and U.K. defense contractor QinetiQ demonstrated the first "stealth" wind-turbine blade--their solution to the aviation radar interference problem holding up the installation of gigawatts-worth of proposed wind farms worldwide.
Vestas composites specialist Steve Appleton says the firm is eager to test a complete stealth turbine and begin limited production by the end of 2010. "Clearly this technology, if proven fully and then adopted by Vestas, would give us a competitive advantage," says Appleton.
Lingering doubts over how stealthy turbines can be, especially when it comes to long-range military radars, are prompting continued research on alternate solutions. Just last month the U.K. government launched an $8.5 million research project with Calgary-based radar system maker Raytheon Canada to make existing air-traffic control systems capable of recognizing and discounting the radar signature from a wind farm.
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from the Los Angeles Times (Registration Required)
A tiny insect that threatens California's $1.6-billion citrus industry has been found near one of the state's commercial citrus growing regions.
The Asian citrus psyllid, which has ravaged orchards in Florida as well as overseas, was found in Valley Center in rural San Diego County, the closest the bug has come to a major concentration of citrus groves.
Northern San Diego County has about 2,500 acres of commercial citrus trees and is home to the largest concentration of organic citrus farmers in the nation, which will complicate efforts to control the insect, said Ted Batkin, president of the Citrus Research Board. "The Valley Center trapping is not a surprise, but it is a real concern. This is very close to several thousand acres of citrus groves," Batkin said.
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from the San Diego Union-Tribune (Registration Required)
WASHINGTON, D.C. (Associated Press) -- The snows of Kilimanjaro may soon be gone. The African mountain's white peak--made famous by writer Ernest Hemingway--is rapidly melting, researchers report.
Some 85 percent of the ice that made up the mountaintop glaciers in 1912 was gone by 2007, researchers led by paleoclimatologist Lonnie Thompson of Ohio State University report in Tuesday's edition of Proceedings of the National Academy of Sciences.
And more than a quarter of the ice present in 2000 was gone by 2007. If current conditions continue "the ice fields atop Kilimanjaro will not endure," the researchers said.
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from the Christian Science Monitor
Astronomers are filling in the blank spaces on their 3-D map of our universe thanks to their ability to sense almost every conceivable form of electromagnetic radiation.
Those blanks include remote regions of space and time when the first stars formed and when young galaxies began to group themselves into gravitationally bound clusters.
Last April, NASA's Swift gamma ray space telescope detected what astronomers called a gigantic "blast from the past." Gamma rays are the most energetic form of electromagnetic radiation. ...Now two international research teams report that those data give direct insight into the unexplored era when the first stars switched on.
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In the aftermath of the worst financial meltdown since the Great Depression, it's natural for people to question the economic principles that got us into such a pickle. What may be surprising, however, is that physicists have joined in to point out that economists ignore the concept of net energy return on investment at our peril. At the same time, some people are taking energy conservation personally and seriously, especially a Massachusetts family who plan to leave the furnace off this winter. And across the continent, a pair of Canadians are planning to open a desalination business that uses solar heat to dramatically reduce the energy required.
Last week saw the Internet celebrate its 40th birthday, and enthusiasts of classical music may be among the most grateful. Faced with high costs, an aging listening public and dwindling endowments, symphonies are increasingly substituting digital approaches for live performances. Computation is also helping out in the medical field, where highly interactive robots are being used to engage with stroke and Alzheimer's patients and autistic children.
In the world of weapons, however, computers are a two-edged sword: Despite efforts to build secure facilities to manufacture "trusted" chips, only 2 percent of integrated circuits used in weaponry come from such plants, risking silicon subversion. Still, technology is on the verge of offering soldiers increased protection from chemical warfare in the form of paints that absorb toxins, protecting those in and around vehicles coated with them.
In a nod to the natural world, biologists are marveling at the eyes of mantis shrimp and hoping to learn ways to build mechanical analogs of these fine optical devices. But the exchange goes both ways: Investigators are studying whether genes inserted into plants to confer disease resistance may provide a fitness advantage if transgenes escape into wild populations.
Finally, as befits Halloween week, the forensic science of facial reconstruction to identify victims turns out to be at least as much forensic art. One of the most successful practitioners uses forensic data only as a starting point for his creative process.
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As if there weren't enough natural disasters to worry about, now there's evidence that we're not always aware when asteroids will strike from space. An asteroid exploded high above Indonesia last month, NASA reported weeks later. This one did no harm but released about three times more energy than the atomic bomb that leveled Hiroshima.
The chief of Russia's space agency says it's time to harness nuclear power for space exploration. Anatoly Perminov has proposed a new nuclear-powered spaceship for prospective manned missions to Mars and other planets.
And it appears Einstein is still right about some fundamental properties about our universe. After timing the travels of gamma rays of differing energies and wavelengths emitted when the universe was half its current age, scientists observed that they arrived at a target within nine-tenths of a second of each other. Einstein's theory of relativity, remember, instructs that the speed of light is constant, independent of its energy, direction and many other factors.
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At the Indigenous Uranium Forum in Acoma, N.M., attendees opposed renewed uranium mining for nuclear energy. They recalled health problems that mining caused to their communities in the past and objected to mining on sacred land. Meanwhile, on the East Coast, two tribes are opposing Cape Wind, an offshore wind farm proposed for Nantucket Sound. Desecrating the site with wind turbines would be detrimental to the tribes' spiritual well-being, they say.
For climate activists attending a wave of more than 4,300 coordinated demonstrations around the globe, the atmosphere—not the energy source—was the bottom line. Their message centered on the number 350, a target "safe" atmospheric concentration of carbon dioxide (in parts per million). The New York Times looked at their message and why some scientists say 350 was a bad choice.
Others say that carbon dioxide concentration alone isn't enough to go on, and the Christian Science Monitor featured efforts to create a global climate index. Like the Dow Jones Industrial Average, the index would distill multiple measures of climate change into a easy-to-understand figure.
The Associated Press, meanwhile, debunked a myth—fueled by recent cooler weather—that the climate isn't even warming. Four independent statisticians analyzed the temperature data and didn't find a cooling trend.
Climate aside, it was a big week for bear news. The San Francisco Chronicle reported that black bears in Yosemite National Park target minivans over other vehicles because they're easy to open and reliably full of food. Or at least crumbs. And the BBC profiled bear biologist Lynn Rogers, who has studied black bear behavior for 43 years. He gains the bears' trust and walks the woods with them to get a closer look at their lifestyle.
Finally, in insect news, researchers in California have found a way to induce war among invasive Argentine ants. And male bed bugs try to mate with other males—until the unwilling target releases a chemical that says "bug off."
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from BBC News Online
A European satellite is set to provide major new insights into how water is cycled around the Earth. The Smos spacecraft will make the first global maps of the amount of moisture held in soils and of the quantity of salts dissolved in the oceans.
The data will have wide uses but should improve weather forecasts and warnings of extreme events, such as floods. A Russian Rokot launcher carrying Smos lifted off from the Plesetsk Cosmodrome in Russia at 0450 (0150 GMT) on Monday.
... The Soil Moisture and Ocean Salinity (Smos) satellite is part of an armada of European spacecraft being sent into orbit over the next few years to study the planet.
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from the New York Times (Registration Required)
WASHINGTON -- As Congress debates legislation to slow global warming by limiting emissions, engineers are tinkering with ways to capture and store carbon dioxide, the leading heat-trapping gas.
But coal-fired power plants, commonly identified as the nation's biggest emissions villain, may not be the best focus.
Rather, engineers and policymakers say, it may be easier and less costly to capture the carbon dioxide at oil refineries, chemical plants, cement factories and ethanol plants, which emit a far purer stream of it than a coal smokestack does.
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from the Washington Post (Registration Required)
The 10 tomatoes sitting in a Tupperware tub at the Food and Drug Administration seem to be doing nothing more than rotting, slowly. But an invisible battle is raging on the surface of the fruit, with provocative implications for food safety and the war that humans have been waging against bacteria for a century.
"This is the wrestling ring," said Eric Brown, a microbiologist at the FDA's Center for Food Safety and Applied Nutrition, as he clicked open the lid to the tub. "This is the smack-down."
Brown and a team of FDA scientists trying to prevent salmonella contamination in tomatoes have stumbled upon what they believe are powerful, naturally occurring "good" bacteria that can slaughter the "bad" bacteria that have become a persistent problem in fresh fruits and vegetables because they harm humans.
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from the Boston Globe (Registration Required)
PAONIA, Colo. -- From the hillsides of extinct volcanoes in Arizona to the jagged peaks of Idaho, aspen trees are falling by the tens of thousands, the latest example of how climate change is dramatically altering the American West.
Starting seven years ago, foresters noticed massive aspen losses caused by parasitical insects, one of which is so rare it is hardly even written about in the scientific literature.
But with warming temperatures and the aftereffects of a brutal drought lingering, the parasites are flourishing at the expense of the tree, beloved for its skinny branches and heart-shaped leaves that turn a brilliant yellow in autumn.
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from USA Today
WASHINGTON (Associated Press) -- What's all the fuss about? After all the noise over Democrats' push for a government insurance plan to compete with private carriers, coverage numbers are finally in: Two percent.
That's the estimated share of Americans younger than 65 who'd sign up for the public option plan under the health care bill that Speaker Nancy Pelosi, D-Calif., is steering toward House approval.
The underwhelming statistic is raising questions about whether the government plan will be the iron-fisted competitor that private insurers warn will shut them down or a niche operator that becomes a haven for patients with health insurance horror stories.
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from Science News
Modeling the climate just got a little more complex. A new simulation that considers chemical interactions between various gases and atmospheric aerosols is giving scientists and policy makers better estimates of the climate-altering effects of those gases, scientists report.
Some atmospheric gases--known as greenhouse gases--trap heat and boost the planet's surface temperature. This process keeps Earth habitable, but nowadays, many scientists say, the planet may be getting too much of a good thing.
Though most climate simulations include the direct, heat-trapping effects of these atmospheric constituents, which can readily be measured in a lab, few account for how their presence either increases or decreases atmospheric concentrations of planet-cooling aerosols, says Drew Shindell, a climate scientist at NASA's Goddard Institute for Space Studies in New York City.
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from Scientific American
Myrtle Beach's popular oceanfront is retreating at a rate of up to 30 centimeters per year. But visitors who flock to that part of South Carolina's Atlantic coast continue to enjoy its wide, sandy stretches, because the state refills them every seven years or so with sediment dredged from the sea bottom.
Deciding whether to re-sand an area of beach is one impetus behind a study by researchers from the U.S. Geological Survey (USGS) and the South Carolina Sea Grant Consortium, who are presenting its findings this week at the International Geological Program Annual Conference in Myrtle Beach.
... By gathering information for the entire bay area, the scientists can make better predictions about erosion rates and the best ways to restore beaches. Moreover, the study's wide-scale approach could be applied to improve erosion projections in other areas.
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from the San Diego Union-Tribune (Registration Required)
Any chance of recovery from a spinal-cord injury, however small, depends on swift treatment. Without that, damaged nerve cells wither, some die and the body becomes paralyzed.
But perhaps the paralysis isn't permanent. Neuroscientists at the University of California San Diego have for the first time successfully regrown axons--fibers that connect nerve cells and conduct their essential communications--in the damaged spinal cords of rats with untreated injuries that are six weeks to more than a year old.
"This work may eventually make it possible to help people with longtime, established spinal-cord injuries," said Dr. Mark Tuszynski, a UCSD professor of neurosciences and co-author of a new paper describing the research in the journal Neuron.
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from the Times (London)
A new "one-step" test allows breast cancer patients to be treated directly if their disease has spread, meaning that they no longer have to wait weeks for test results to come back or undergo a second operation.
Surgeons say that thousands of women undergoing surgery could benefit from the rapid diagnostic test, known as the breast lymph node assay. It is already being used at hospitals in Surrey and Portsmouth, and is due to be recommended for implementation across the NHS next year.
Quicker and more reliable than existing checks, it involves analysing the glands under the arms, to check if the cancer has already spread, at the same time as a patient has a mastectomy or surgery to remove an initial tumour.
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from the Los Angeles Times (Registration Required)
The Nazca people of Peru--famous for their huge line drawings on an arid plateau that are fully visible only from the air--set the stage for their demise by deforesting the plain, allowing a huge El Niño-fueled flood to ravage the Ica Valley about AD 500, researchers have found.
"They died out because they destroyed their natural ecosystem," said archaeologist Alex J. Chepstow-Lusty of the French Institute of Andean Studies in Lima, coauthor of a paper in the current issue of Latin American Antiquity. "As the population expanded, they put in too many fields and didn't protect the landscape. The El Niño wiped away society."
Chepstow-Lusty, David Beresford-Jones of the University of Cambridge and their colleagues used pollen in the soil to trace the horticultural history of the valley, revealing environmental depredation.
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from Scientific American
We all know someone who is not as smart as we are--and someone who is smarter. At the same time, we all know people who are better or worse than we are in a particular area or task, say, remembering facts or performing rapid mental math calculations.
These variations in abilities and talents presumably arise from differences among our brains, and many studies have linked certain very specific tasks with cerebral activity in localized areas. Answers about how the brain as a whole integrates activity among areas, however, have proved elusive. Just what does a "smart" brain look like?
Now, for the first time, intelligence researchers are beginning to put together a bigger picture. Imaging studies are uncovering clues to how neural structure and function give rise to individual differences in intelligence. The results so far are confirming a view many experts have had for decades: not all brains work in the same way. People with the same IQ may solve a problem with equal speed and accuracy, using a different combination of brain areas.
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from Seed
When delegates from 192 nations arrive in Copenhagen in December for the UN COP15 summit, they will confront a 181-page draft negotiation text, 2,000 bracketed passages still in dispute, and just 11 days in which to come to some sort of consensus. To power them through these discussions, Denmark has promised a smorgasbord of ecologically minded fare: All water will be tap (not bottled), tea and coffee will be fair trade, and the food menu will be no less than 65 percent organic.
Though undoubtedly well-intentioned, this last provision is troubling, but not because anyone really cares about the provenance of Ban Ki-Moon's turnip greens. Rather, it suggests a willful and dangerous ignorance about the tenuous state of global agriculture, and the prospects for feeding 9 billion people while also addressing biodiversity loss, water shortage, and, yes, climate change.
Organic foods are enjoying skyrocketing popularity in the US and Europe, as are their ill-defined sidekicks, "natural," "whole," and "real" foods. Yet popular notions that these foods--and the agriculture that begets them--are at once better for people and for the planet turn out to be largely devoid of experimental support. Worse still, "organophilia" tends to go hand-in-hand with technophobic skepticism towards the very sorts of scientific approaches most likely to supercharge an ailing food system while leaving our planet intact.
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from the Wall Street Journal
WASHINGTON -- The number of confirmed cases of H1N1 flu from April to July represents just 2% of the actual people who were infected with the virus, according to a report by the Center for Disease Control and Prevention.
The report, posted to the agency's Web site, says the number of people infected with H1N1 flu from April to July likely was between 1.8 million and 5.7 million, much higher than the 43,677 confirmed cases. The paper also said the virus hospitalized 9,000 to 21,000 people during the same period.
The study shows the prevalence of the virus is more widespread than originally reported. The CDC and World Health Organization in July stopped tracking individual cases because they acknowledged doing so was difficult.
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from Science News
Male bed bugs get confused in bed. Now a scientist has found a bug chemical signal that translates, "Whoa, buddy. I'm a guy too."
Male bed bugs grasp and try to mate with any other member of their Cimex lectularius species that has had a full meal of blood recently, says chemical ecologist Camilla Ryne of Lund University in Sweden. Single-minded males don't seem inclined, or even able, to distinguish other males from females at first.
At first contact, sex recognition for these insects works largely by trial and error, Ryne says. What corrects those errors, she has found, is a blend of chemicals that earlier work has also described as the bed bug alarm pheromone.
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from USA Today
The National Institutes of Health will devote $30 million to study the safety of bisphenol A, or BPA, an estrogen-like chemical used in many plastics, including sippy cups and the linings of metal cans.
Almost half of that money comes from the economic stimulus bill, says Robin Mackar, spokeswoman for the National Institute of Environmental Health Sciences (NIEHS).
Although a growing number of scientists and consumers are concerned about BPA -- which has been detected in the urine of more than 90% of Americans -- government agencies have been divided about whether it poses a threat.
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from the Economist
There is a lot of water on Earth, but more than 97% of it is salty and over half of the remainder is frozen at the poles or in glaciers. Meanwhile, around a fifth of the world's population suffers from a shortage of drinking water and that fraction is expected to grow.
One answer is desalination--but it is an expensive answer because it requires a lot of energy. Now, though, a pair of Canadian engineers have come up with an ingenious way of using the heat of the sun to drive the process. Such heat, in many places that have a shortage of fresh water, is one thing that is in abundant supply.
Ben Sparrow and Joshua Zoshi met at Simon Fraser University in Vancouver, while completing their MBAs. Their company, Saltworks Technologies, has set up a test plant beside the sea in Vancouver and will open for business in November.
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from New Scientist
Autoimmune disease has devastating consequences for healthy tissue. Now, in mice, the same cells that can drive the body to destroy its own tissue have been used to fight cancer.
The cells are a recently discovered type of immune cell called Th17. These cells play a key role in autoimmune disease--in which the immune system mistakenly identifies the body's own tissues as foreign and attack them.
We already know that some people's immune systems have a natural ability to fight some types of cancer. But how exactly this works--and why it doesn't always do so--isn't known.
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from the Guardian (U.K.)
Scientists have turned human stem cells into early-stage sperm and eggs in research that promises to give doctors an unprecedented insight into the causes of infertility.
The work will allow researchers to study human reproductive cells from the moment they are created in embryos through to fully-mature sperm and eggs.
Understanding the details of how sperm and egg cells grow will help scientists develop treatments for people who are left infertile when the process goes wrong. The research may also lead to treatments that can correct growth defects before a child is born.
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