Scientific American - Basic Science
Science news and technology updates from Scientific American
Got E. coli ? Raw Milk's Appeal Grows Despite Health Risks
Tue, 31 Aug 2010 10:00:00 EST
Milk is well known as a great dietary source of protein and calcium, not to mention an indispensable companion to cookies. But "nature's perfect food," a label given to milk over time by a variety of boosters, including consumer activists, government nutritionists and the American Dairy Council, has become a great source of controversy, too. The long-running dispute over whether milk, both from cows and goats, should be consumed in raw or pasteurized form--an argument more than a century old--has heated up in the last five years, according to Bill Marler , a Washington State lawyer who takes raw milk and other food poisoning cases. [More]
Raw Milk - Milk - Pasteurization - United States - Health
Worms for brains: Can genes point the way to the cerebral cortex's common ancestor with marine annelids?
Thu, 02 Sep 2010 16:10:00 EST
Marine worms might seem like lowly, slow-witted creatures, but new gene mapping shows that we might share an ancient brainy ancestor with them. [More]
Gene - Annelid - Cerebral cortex - Common descent - Worms
Rabbit Rest: Can Lab-grown Human Skin Replace Animals in Toxicity Testing?
Thu, 02 Sep 2010 12:10:00 EST
It likely comes as no surprise that many common household chemicals and medical products as well as industrial and agricultural chemicals, may irritate human skin temporarily or, worse, cause permanent, corrosive burns. In order to prevent undue harm regulators in the U.S. and beyond require safety testing of many substances to identify their potential hazards and to ensure that the appropriate warning label appears on a product. Traditionally, such skin tests have been done on live animals--although in recent decades efforts to develop humane approaches , along with ones that are more relevant to people have resulted in new models based on laboratory-grown human skin.
The most recent chapter of this ongoing effort was written on July 22 when the Organization for Economic Cooperation and Development (OECD)--an international group that, among other things, provides guidelines to its 32-member countries on methods to assess chemical safety--officially approved three commercially available in vitro models of human skin for use in chemical testing. Specifically, the new guideline ( OECD Test No. 439 ) stipulates that the models can serve as an alternative to animals in tests for skin irritation, one of several human health endpoints for which chemicals are tested. Similar 3-D models were approved for corrosion tests in 2004, leaving many hopeful that soon it may be possible to the assess the full spectrum of a chemical's effects on human skin--from irritation to corrosion--without using live animals.
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United States - Health - Organisation for Economic Co-operation and Development - Toxicity - Medicine
Engineering students happily deafened by Mwanga metalworkers
Tue, 31 Aug 2010 15:00:00 EST
Editor's Note: Students from Dartmouth's Thayer School of Engineering are working in Tanzania to help improve sanitation and energy technologies in local villages. The student-led group , known as Humanitarian Engineering Leadership Projects (HELP), will file dispatches from the field during their trip. This is their seventh blog post for Scientific American.
The rooster in the room next to us crowed loudly at sunrise, and we despondently got out of bed with the goal of finding Fundi [see photo at left] , the town of Kalinzi's elusive stove maker. We found him farming and arranged to meet with him after work at the seventh hour of the Swahili clock, 1 p.m. international time (Swahili time starts with the first hour of sunlight and is therefore six hours behind). [More]
Tanzania - Swahili language - Thayer School of Engineering - Engineering - Dartmouth College
Mapping the Mind: Online Interactive Atlas Shows Activity of 20,000 Brain-Related Genes (preview)
Thu, 02 Sep 2010 09:00:00 EST
Scientists have long sought to understand the biological basis of thought. In the second century A.D., physician and philosopher Claudius Galen held that the brain was a gland that secreted fluids to the body via the nerves--a view that went unchallenged for centuries. In the late 1800s clinical researchers tied specific brain areas to dedicated functions by correlating anatomical abnormalities in the brain after death with behavioral or cognitive impairments. French surgeon Pierre Paul Broca, for example, found that a region on the brain’s left side controls speech. In the first half of the 20th century, neurosurgeon Wilder Penfield mapped the brain’s functions by electrically stimulating different places in conscious patients during neurosurgery, triggering vivid memories, localized body sensations, or movement of an arm or toe.
In recent years new noninvasive ways of viewing the human brain in action have helped neuroscientists trace the anatomy of thought and behavior. Using functional magnetic resonance imaging, for instance, researchers can see which areas of the brain “light up” when people perform simple movements such as lifting a finger or more complex mental leaps such as recognizing someone or making a moral judgment. These images reveal not only how the brain is divided functionally but also how the different areas work together while people go about their daily activities. Some investigators are using the technology in an attempt to detect lies and even to predict what kinds of items people will buy; others are seeking to understand the brain alterations that occur in disorders such as depression, schizophrenia, autism and dementia.
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Brain - Functional magnetic resonance imaging - Neurosurgery - Health - Human brain
The Deepening Crisis: When Will We Face the Planet's Environmental Problems?
Wed, 01 Sep 2010 08:00:00 EST
With this final column I will transition Sustainable Developments from Scientific American to the home page of the Earth Institute ( www.earth.columbia.edu ). Although I will continue to contribute occasional essays to the magazine, I will use this last regular column to say thank you and take stock of the deepening crisis of sustainable development.
During the four years of this column, the world’s inability to face up to the reality of the growing environmental crisis has become even more palpable. Every major goal that international bodies have established for global environmental policy as of 2010 has been postponed, ignored or defeated. Sadly, this year will quite possibly become the warmest on record, yet another testimony to human-induced environmental catastrophes running out of control.
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Sustainable development - Environment - Earth - The Earth Institute - Environmental policy
A Few Drug-Resistant Bacteria May Keep the Whole Colony Alive
Wed, 01 Sep 2010 12:58:08 EST
There’s been an unexpected development in our understanding of drug resistance in bacteria. The accepted scenario was a simple case of evolutionary selection. In a bacterial population exposed to a killer drug, a few lucky individuals might have a genetic mutation that kept them alive. They survived to reproduce, while the rest of the population perished. In short order, the entire colony consisted only of the offspring of the drug-resistant founders. [More]
Bacteria - Drug resistance - Population - Mutation - Health
Shaky Ground: Can Seismologists Be Charged with a Crime for Not Predicting Deadly Quakes?
Thu, 02 Sep 2010 08:00:00 EST
The adage “damned if you do, damned if you don’t” does not quite capture the following pair of situations. It’s more like “damned if you could (but you can’t), damned if you couldn’t (but you kind of did).”
First, the “damned if you could (but you can’t)”. On April 4 at 3:40 p.m., a magnitude 7.2 earthquake rocked Baja, Mexico, and was felt well north. The event elicited the following post on Twitter 16 minutes later from New Age lifemeister Deepak Chopra: “Had a powerful meditation just now--caused an earthquake in Southern California.” (Lawrence Krauss, too, lays into Deepak on page 36 for his lack of understanding of quantum physics. There’s plenty to bust Chopra about.)
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Mexico - Southern California - Earthquake - New Age - California
Pox Swap: 30 Years After the End of Smallpox, Monkeypox Cases Are on the Rise
Tue, 31 Aug 2010 11:00:00 EST
The ancient scourge smallpox was relegated to biowaste bin of history more than 30 years ago, the result of the world's first and only successful disease eradication programs. Since then, however, cases of monkeypox--a serious, although less severe smallpoxlike illness--have substantially increased in central Africa, according to a study published August 30 in Proceedings of the National Academy of Sciences . The authors stress that better surveillance and a thorough assessment of the public health threat posed by this once-rare viral infection are needed.
"I'm concerned about monkeypox," says Don Burke director of the Center for Vaccine Research at the University of Pittsburgh, who wasn't involved in the study. "It isn't going to emerge as pandemic tomorrow, but could at any time start to increase its transmission. It's worrisome. This is the type of warning siren we need to take very seriously."
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Africa - University of Pittsburgh - Smallpox - Central Africa - Public health
Ants Protect Acacia Trees from Elephants
Thu, 02 Sep 2010 12:08:08 EST
We all know that elephants aren’t really scared of mice. But a new study shows that they’re really not crazy about something even smaller: ants. In fact, elephants dislike ants so much that they avoid acacia trees that harbor the tiny, six-legged nectar-suckers. [More]
Biology - Flora and Fauna - Animalia - Insecta - Hymenoptera
If the world is going to hell, why are humans doing so well?
Wed, 01 Sep 2010 06:00:00 EST
For decades, apocalyptic environmentalists (and others) have warned of humanity's imminent doom, largely as a result of our unsustainable use of and impact upon the natural systems of the planet. After all, the most recent comprehensive assessment of so-called ecosystem services -- benefits provided for free by the natural world , such as clean water and air--found that 60 percent of them are declining. [More]
Drinking water - Environmentalism - Human - Environment - Water
Dinner Party Discovered 12,000 Years Later
Tue, 31 Aug 2010 11:10:08 EST
We humans love excuses to gather for a rousing evening of community--featuring lots of food. Now researchers have evidence for the earliest known group feasting.
At a 12,000-year-old burial site in northern Israel, archaeologists found the remains of at least 71 tortoises and two wild cattle in specially built hollows in a cave. The tortoise shells surrounded the remains of individuals who the scientists say were shamans. And there’s evidence that the animals were cooked and eaten. Based on the bones, the researchers estimate that the meat could have supported about 35 people, maybe more.
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Archaeology - Israel - Human - Social Sciences - Burial
Dammed if they don't: Cost to protect endangered sturgeon in South Carolina could be $100 million, utility says
Tue, 31 Aug 2010 09:00:00 EST
How much will it cost to protect an endangered fish in South Carolina? The National Marine Fisheries Service (NMFS) wants local utility Santee Cooper to make several changes to its dams on Marion and Moultrie lakes, which would help endangered shortnose sturgeon ( Acipenser brevirostrum ) to pass through the dams and breed. But Santee Cooper says the changes NMFS wants will cost more than $100 million. [More]
National Marine Fisheries Service - South Carolina - Santee Cooper - Endangered species - United States
Toxic avenger: One man's desperate idea to save the rhinos--poison their horns
Wed, 01 Sep 2010 11:00:00 EST
With rhinoceros poaching in Africa approaching an all-time high , one nature preserve owner has had enough. Ed Hern, owner of the Rhino and Lion Nature Reserve near Johannesburg, South Africa, is experimenting with injecting cyanide into his rhinos' horns. He believes the poison will not harm the rhinos, because there are no blood vessels in the horn to carry the poison the rest of the rhino's body. But if anyone kills the animals and sells the horns for use in traditional Asian medicine, the end-consumer could pay the ultimate price. [More]
South Africa - Africa - Poaching - Rhinoceros - Medicine
Money Buys Unhappiness
Tue, 31 Aug 2010 09:00:00 EST
“ ’Tis the gift to be simple,” the Shakers sing. Catholic nuns and Buddhist monks take vows of poverty. Why? A new study published online in May in Psychological Science offers a hint. Money--even the thought of it--reduces satisfaction from life’s simple pleasures.
Studies have shown that a person’s ability to savor experiences predicts their degree of happiness. Savoring is defined as the emotions of joy, awe, excitement and gratitude derived during an experience. Psychologist Jordi Quoidbach of the University of Liège in Belgium and his colleagues divided 374 adults, ranging from custodians to senior administrators, into two randomly assigned groups. The first group was shown a picture of a stack of money; the control group was shown the same picture blurred beyond recognition. Then the participants were given psychological tests to measure their ability to savor pleasant experiences. The results showed that people who had been shown the money scored significantly lower.
[More]
Psychology - Belgium - Happiness - Scientific control - Jordi Quoidbach
New Microscope Enables Real-Time 3-D Movies of Developing Embryos [Slide Show]
Wed, 01 Sep 2010 16:50:00 EST
Using a revolutionary new microscope, scientists can now peer into embryos and watch, in one of the world's smallest 3-D movies, as brains, eyes and other organs form. A team at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, watched zebra fish and fruit fly embryos develop under the scope for as long as 58 hours, charting the location of every cell as it danced around the embryo. This experiment would have been impossible a mere two years ago before a recent spate of innovations advanced microscopy years into the future.
When it comes to watching the inner workings of cells , fluorescence microscopy is second to none. In this technique, scientists attach fluorescent tags to cellular proteins and, by shining a laser on the cells, cause them to light up.
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European Molecular Biology Laboratory - Heidelberg - Zebrafish - Biology - Embryo
Physics of free kicks: The hidden advantage of long-distance soccer shots
Thu, 02 Sep 2010 13:10:00 EST
When Brazilian defender Roberto Carlos struck a powerful free-kick from about 30 meters out in a 1997 international match against France, he could not have known that scientists would still be discussing his feat more than a dozen years later. Indeed, he could not even have known that the ball would improbably find the back of the net . But find the net it did, swinging well wide of a wall of French defenders, hooking viciously to the left, and glancing off the inside of the goalpost. The French goalkeeper could only turn and watch in apparent disbelief as the ball came to rest in his goal. [More]
Roberto Carlos - Physics - France - Association football - Goalkeeper
New science blog networks mushroom to life
Wed, 01 Sep 2010 13:00:00 EST
The science blogosphere is shrinking and growing at the same time. Today, the Public Library of Science (PLoS) starts a new network called PLoS Blogs . A nonprofit publisher of open-access journals focused on biological sciences, PLoS will fold its three existing blogs under its new network, managed by Brian Mossop (the author of a recent Mind Matters column on fatherhood here). [More]
Public Library of Science - Publishing - Open access journal - Biology - Blog
Democracy's Laboratory: Are Science and Politics Interrelated?
Tue, 31 Aug 2010 08:00:00 EST
Do you believe in evolution? I do. But when I say "I believe in evolution," I mean something rather different than when I say “I believe in liberal democracy.” Evolutionary theory is a science. Liberal democracy is a political philosophy that most of us think has little to do with science.
That science and politics are nonoverlapping magisteria (vide Stephen Jay Gould’s model separating science and religion) was long my position until I read Timothy Ferris’s new book The Science of Liberty (HarperCollins, 2010). Ferris, the best-selling author of such science classics as Coming of Age in the Milky Way and The Whole Shebang , has bravely ventured across the magisterial divide to argue that the scientific values of reason, empiricism and antiauthoritarianism are not the product of liberal democracy but the producers of it.
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Stephen Jay Gould - Evolution - Liberal democracy - Political philosophy - Relationship between religion and science
Shades of "Gray Literature": How Much IPCC Reform Is Needed?
Mon, 30 Aug 2010 16:45:00 EST
The Intergovernmental Panel on Climate Change's 2007 report from the group working on global warming's impacts contained at least one error. "Glaciers in the Himalaya are receding faster than in any other part of the world (see Table 10.9) and, if the present rate continues, the likelihood of them disappearing by the year 2035 and perhaps sooner is very high if the Earth keeps warming at the current rate," the report notes. [More]
Intergovernmental Panel on Climate Change - Climate change - Global warming - Environment - Climate Change: The Ipcc Response Strategies
