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In Study, Drug Delays Worsening of Breast Cancer, With Fewer Side Effects

from the New York Times (Registration Required)

CHICAGO -- A drug that delivers a powerful poison to tumors without some of the side effects of traditional treatments can delay the worsening of breast cancer and also appears to substantially prolong lives, according to results of a study presented here [the American Society of Clinical Oncology] Saturday.

Besides representing an advance in treating breast cancer, the success in the clinical trial validates an idea that is now being pursued by numerous pharmaceutical companies to treat various types of cancer in a way that delivers drugs to cancerous cells while sparing healthy ones.

"We've envisioned a world where cancer treatment would kill the cancer and not hurt the patient," Dr. Kimberly L. Blackwell, a professor of medicine at the Duke Cancer Institute and the lead investigator in the trial, said in an interview. "And this drug does that."

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Venus Transit Day: Don't Miss this Twice-in-a-Lifetime Experience

from the Chicago Tribune (Registration Required)

Tuesday is Venus transit day--that hole-in-the-sun journey taken by our neighboring planet--and unlike the last time this occurred, the event will be visible to all of North America. Not that you should look at it. As NASA notes, Venus is too minuscule to block the blinding glare of the sun. You need a filter. NASA suggests No. 14 welder's glasses.

You might be better off contacting a local astronomy club, which probably will have solar telescopes for observing the transit. In Los Angeles, the Griffith Observatory will have telescopes set up on the lawn for free viewing, as the [Los Angeles] Times reported Thursday.

But however you safely do it, get a glimpse if you can. NASA helpfully notes that the next time it occurs, we will all be dead. Thanks for that, NASA. Truly, these transits are a twice-in-a-lifetime experience. They come in pairs a few years apart. The first in this pair was in 2004. The next transit is December 2117.

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Treatment Helps Paralyzed Rats Walk

from Science News

Scientists have trained paralyzed rats to walk, run and even climb stairs. Weeks of rigorous practice coupled with an electrochemical spine-stimulating regimen allowed the animals to overcome devastating spinal cord injuries that immobilized their rear legs, Swiss scientists report in the June 1 Science.

Although preliminary, the results offer hope to people paralyzed by spinal cord injuries. "The really exciting thing, the take-home message for people living with spinal cord injuries, is that this represents yet another step towards real treatment," says neurologist John McDonald of the Kennedy Krieger Institute in Baltimore and the Johns Hopkins University School of Medicine. "The real beauty is that this is not something that would necessarily have to go through 10 years of FDA approval."

Recovery, the Swiss team found, relied on a combination of treatments, all readily adaptable to humans: Nerve cells in the spine below the damaged site were stimulated with a cocktail of drugs similar to some antidepressants. Electrical shocks, delivered via electrodes, also activated the spine. In this way, the researchers primed the rats for the next stage of treatment--learning to walk again.

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Private Spacecraft Returns to Earth

from the New York Times (Registration Required)

CAPE CANAVERAL, Fla. (Associated Press) -- The SpaceX Dragon supply ship returned to Earth on Thursday, ending its revolutionary nine-day voyage to the International Space Station with an old-fashioned splashdown in the Pacific.

The unmanned capsule parachuted into the ocean about 500 miles off Mexico's Baja California, bringing back more than a half-ton of old station equipment. It was the first time since the space shuttles stopped flying last summer that NASA got back a big load from the orbiting lab.

Thursday's dramatic arrival of the world's first commercial cargo carrier capped a test mission that was virtually flawless, beginning with the May 22 launch aboard the SpaceX company's Falcon 9 rocket from Cape Canaveral and continuing through the space station docking three days later and the departure a scant six hours before it hit the water.

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White Dwarf Star Measurements Bring Milky Way into Focus

from the Los Angeles Times (Registration Required)

White dwarf stars are dying stars--burned-out cinders that have exhausted the hydrogen that sustains them. But scientists may soon count on these stellar flameouts to unravel the history of the Milky Way.

In a study published online Wednesday by the journal Nature, astronomer Jason Kalirai described a new technique for calculating the masses and ages of old stars based on the masses of the white dwarfs they have become.

The new information will help researchers better understand the formation of Earth's galaxy. "If we want to assess when components of the Milky Way formed, we need the ages of the stars," said Kalirai, who is based at the Space Telescope Science Institute in Baltimore.

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Single-Celled Office Mates, by the Thousands

from the New York Times (Registration Required)

Men's offices have more bacteria than women's offices. Not only that: Offices in New York City house more bacteria than those in San Francisco.

These are among the findings of a new study in the journal PLoS One that looks at bacteria in more than 90 offices in three cities--San Francisco, New York and Tucson--and on five types of surfaces: chairs, desktops, phones, computer mice and keyboards.

The bacteria count in men's offices was 10 to 20 percent greater than in women's. "It could be men are just bigger--they have bigger mouths and more surface area--but it could also be that men are less hygienic," said an author of the study, Scott Kelley, a microbiologist at San Diego State University.

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What Volcanic Crystals Tell Us About the Evolution of Mount St. Helens

from Wired

One of the major reasons I (Erik Klemetti) am a geologist is that I love history. I majored in both history and geology as an undergraduate because I am fascinated by unraveling what has happened in the past and what was the evidence that we can use to see those events. For me, it is the crystals in volcanic rocks that hold the key to understanding the evolution of magma at volcanoes--they record events in crystalline structure through crystal growth, changing compositions of the crystals or incorporation of radioactive elements that can be used as a stopwatch.

Even after the crystal forms, the elements are redistributed to show how time has passed. Two studies that came out this week examining St. Helens and Long Valley use these tools to unlock the unseen history of the volcanoes. These crystals hold the story of the volcano, in both the long and short term, and reading that history is what fascinates me.

To read the history in crystals, you need to know that "ages" in geology don't all come the same. There are two types of ages when we consider almost any geochronologic information--relative and absolute ages. The latter is straight forward--an absolute age is one where you can assign a specific date to the event in question.

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Great White Egrets Breed in UK for First Time

from BBC News Online

Great white egrets are breeding in the UK for the first time at a Somerset nature reserve. At least one chick has hatched at Shapwick Heath National Nature Reserve, it has been confirmed, setting a new UK breeding bird record.

To have the egrets, a species of heron and rare visitors to the UK, breeding in the country was "incredibly exciting", manager Simon Clarke said. There have also been unconfirmed sightings of a second chick.

"It was a great sense of relief when we confirmed we have got at least one chick on the nest," Mr. Clarke told BBC Nature.

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Did Retained Juvenile Traits Help Birds Outlive Dinosaurs?

from Scientific American

Birds are the only dinosaurs that have survived into modern times. Why is that? Of all the dinosaur species, how did they manage to make it through the catastrophic events of 65 million years ago, whereas all their fellow dinos perished? A new study, published May 27 in Nature, hints at an evolutionary phenomenon that may have played to birds' advantage: They are, it seems, baby dinosaurs whose biology prevents them from ever growing up.

Bhart-Anjan Bhullar and his doctoral advisor, Arkhat Abzhanov, posit that birds may have evolved from dinosaurs by a process known as paedomorphosis, whereby an organism retains juvenile traits even after it becomes sexually mature. "They certainly look to have some paedomorphic characteristics," says Jack Horner, a Montana State University paleontologist who studies dinosaur growth and development and was not involved in the study. Paedomorphosis "is not uncommon in evolution and speciation," he adds.

Bhullar and Abzhanov reached this conclusion by comparing the skulls of birds and dinosaurs across phylogenies, or related groups, and at different developmental stages. To quantitatively compare cranial geometries, they scanned the skulls of theropod dinosaurs (which are thought to be birds' ancestors), crocodiles and alligators (dinosaurs' cousins), early transitional birds such as Archaeopteryx, and modern birds. Then they created digitized versions of each skull and mapped out cranial landmarks, such as nostril tips, eye socket dimensions and places where bones meet.

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Coastal N.C. Counties Fighting Sea-Level Rise Prediction

from the Charlotte Observer

State lawmakers are considering a measure that would limit how North Carolina prepares for sea-level rise, which many scientists consider one of the surest results of climate change. Federal authorities say the North Carolina coast is vulnerable because of its low, flat land and thin fringe of barrier islands. A state-appointed science panel has reported that a 1-meter rise is likely by 2100.

The calculation, prepared for the N.C. Coastal Resources Commission, was intended to help the state plan for rising water that could threaten 2,000 square miles. Critics say it could thwart economic development on just as large a scale.

A coastal economic development group called NC-20 attacked the report, insisting the scientific research it cited is flawed. The science panel last month confirmed its findings, recommending that they be reassessed every five years.

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'Lung Washing' Could Boost Transplants

from BBC News Online

"Washing" lungs before they are transplanted could increase numbers of the organs suitable for donation, according to doctors in Newcastle. Only one in five donated lungs are good enough to be transplanted safely.

A trial, being led by Newcastle University, is trying to improve the quality of the lungs by pumping nutrients and oxygen through them. The British Transplantation Society said the technique could "dramatically" increase the number of lungs used.

Around a quarter of people waiting for an organ transplant die in the first year on a transplant list. The lungs are delicate organs and the events which lead to a donor's death can also damage the lungs. It is why so few can be transplanted.

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Soft Drinks Targeted by Anti-Obesity Campaigners

from the Guardian (UK)

It's the cinemas that the nutrition adviser Susan Jebb worries about most. People do not generally buy cola in supersized buckets, but in the cinema we do, along with vast tubs of popcorn. A large 16oz cup of cola contains 16 teaspoons of sugar, according to the Harvard School of Public Health. That is a potentially considerable problem for the waistline.

"Because it is in liquid form, the evidence is that [a sugary drink] doesn't fill you up," says Jebb. "They seem to supplement our food rather than substitute. If people have 400 calories of Jelly Babies or 400 calories of drink, they may eat less after the Jelly Babies, but they don't decrease their calories at all after the drink."

Sugary drinks are increasingly indicted as partly responsible for the expanding girth of western nations. Jebb, head of diet and population health at the Medical Research Council Human Nutrition Research unit in Cambridge, is excited by New York mayor Michael Bloomberg's plan to ban sugary drinks being sold in containers larger than 16oz. http://www.guardian.co.uk/business/2012/may/31/soft-drink-obesity

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Tumor Blocker May Fight Fibrosis

from ScienceNOW Daily News

Connective tissue holds our bodies together, but in a condition called fibrosis, an overabundance of the material devastates organs such as the liver, heart, and lungs. A new study suggests that fragments of a promising cancer drug can rein in fibrosis, which is currently untreatable.

Fibrosis occurs when cells pump out excess collagen and other connective tissue proteins, which harm organs. Pulmonary fibrosis, for example, stiffens the lungs, eventually suffocating patients unless they receive a lung transplant. In people with cirrhosis, connective tissue crams into the liver. Heart and kidney disease can also be caused by fibrosis. So far, no drugs to stop or reverse fibrosis have won approval in the United States.

Cell and molecular biologist Carol Feghali-Bostwick of the University of Pittsburgh School of Medicine in Pennsylvania and colleagues decided to test whether endostatin, a drug undergoing clinical trials as a treatment for various cancers, also has an effect on fibrosis. Endostatin is one of the so-called angiogenesis inhibitors, a group of much-touted drugs that block the formation of new blood vessels that tumors need for growth. Endostatin also occurs naturally in the human body, and patients with lung fibrosis have up to 20 times the normal levels in their blood or lungs. That observation raised the possibility that the protein is a natural defense against connective-tissue overgrowth, says Feghali-Bostwick.

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In Wild Animals, Charting the Pathways of Disease

from the New York Times (Registration Required)

BOZEMAN, Mont. -- High in the Wallowa Mountains of northeastern Oregon, Raina K. Plowright and other researchers blindfolded and hobbled a herd of bighorn sheep in a corral so blood samples could be taken and their noses and throats swabbed.

"There's lots of places for pathogens to hide in the nasal cavity," said Dr. Plowright, a wildlife scientist with the Center for Infectious Disease Dynamics at Penn State who is based in Bozeman.

Peering into the nostrils of wild sheep is part of the nascent field of eco-immunology, which seeks both to understand the immune systems of wild animals and to use that knowledge to gain a better understanding of human immune systems. Until recently, this kind of knowledge has been gleaned almost exclusively by studying pampered, genetically similar lab animals, which don't reflect a real-world scenario.

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Prescription Pads Play Key Role in Drug Abuse

from the San Francisco Chronicle

Los Angeles (Associated Press) -- The small pads that doctors use to scribble out prescriptions, a seemingly innocent part of the medical profession, have played a role in the surge of prescription drug abuse.

Take a diagnostic imaging center in the San Fernando Valley where investigators in March found thousands of unsigned pads that were stored there as part of a suspected Medicare fraud scam. Or the case of Dr. Lisa Barden in Riverside County, where authorities found she had pads stolen from a dozen doctors to obtain Vicodin and OxyContin.

There's a growing sentiment among law enforcement and some legislators that in the computer age it no longer makes sense to rely on paper "scripts" that drug abusers and pill pushers can steal or fabricate to get what they want. Those who are trying to combat prescription drug abuse believe creating a system that provides a direct link from a doctor to a pharmacy may be the best and more cost-effective solution.

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Dormice Whiskers Aid Tree-Climbing

from BBC News Online

Dormice use their whiskers to help them climb trees, researchers say. By twitching them upwards, outwards and straight ahead up to 25 times a second, they sense where they are going, a University of Sheffield team has found.

The process, called whisking, is used by some other rodents, and by whiskered mammals including seals and walruses. Dr Robyn Grant, from the university's Active Touch Laboratory says whisking is "a parallel sense to our sense of touch".

She says hazel dormice (Muscardinus avellanarius) use their whiskers, or vibrissae, in a similar way to how people use their eyes--scanning to recognise what is in front of them. "Because of the uneven surface on branches, they vibrate them to find where to put their feet, as well as to work out where there's a gap and where to change branches," says Dr Grant. Dormice are endangered in the UK and hibernate most of the year in small nests on the ground, but in the summer they live in trees.

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Even in Coal Country, the Fight for an Industry

from the New York Times (Registration Required)

LOUISA, Ky. -- For generations, coal has been king in this Appalachian town. It provided heat, light and jobs for the hundreds of people who worked in the nearby coal mines and the smoke-coughing Big Sandy power plant that burned their black bounty.

But now, coal is in a corner. Across the United States, the industry is under siege, threatened by new regulations from Washington, environmentalists fortified by money from Michael R. Bloomberg, the billionaire mayor of New York City, and natural gas companies intent on capturing much of the nation's energy market.

So when the operator of the Big Sandy plant announced last year that it would be switching from coal to cleaner, cheaper natural gas, people here took it as the worst betrayal imaginable.

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Two Colorado Companies Create Less-Costly Vehicle to Send into Stratosphere

from the Denver Post

COLORADO SPRINGS -- George Bye and Ron Oholendt are a couple of retired "flyboys" who share the same dream of getting an unmanned airship to the stratosphere.

The former Air Force entrepreneurs think that StarLight--a two-stage system with a planelike vehicle suspended below a massive gas-filled balloon--is the answer to a longtime challenge. There had to be a less-costly way to send instruments for surveillance and telecommunications into the upper atmosphere where they could operate for long periods.

"The problem was people took what worked in low altitude and tried it at high altitude, and that didn't work," said Oholendt, president of Global Near Space Services of Colorado Springs. Oholendt and Bye, chief executive of Bye Aerospace of Englewood, discarded a 70-year-old design for an airship that resembles a blimp. Instead, Oholendt's company turned to a "lighter-than-air" concept of a 300-foot-long, 290-foot-high and 90-foot-thick balloon.

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Flavour Changer: Genome Could Enhance Tomato Taste

from BBC News Online

The successful sequencing of the tomato genome will lead to tastier varieties within five years say scientists. They believe that the elusive flavour of home grown tomatoes will by then be widely available in supermarkets. Writing in the journal Nature, the researchers say the genetic information could reduce the need for pesticides.

The authors believe the genome will also boost conventional breeding techniques over genetic modification. While the sheer numbers and varieties of tomatoes available in UK shops have increased substantially in the past 20 years, many consumers would complain that this growth has been at the expense of flavour.

Scientists like Professor Graham Seymour at the University of Nottingham would tend to agree. "In the early 1990s what changed the tomato industry was the use of non-ripening mutant genes, genes that came from natural mutations that have been used to extend shelf life in the fruit.

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DNA Drawing with an Old Twist

from Nature News

Scientists have developed a way to carve shapes from DNA canvases, including all the letters of the Roman alphabet, emoticons and an eagle's head.

Bryan Wei, a postdoctoral scholar at Harvard Medical School in Boston, Massachusetts, and his colleagues make these shapes out of single strands of DNA just 42 letters long. Each strand is unique, and folds to form a rectangular tile. When mixed, neighbouring tiles stick to each other in a brick-wall pattern, and shorter boundary tiles lock the edges in place.

In their simplest configuration, the tiles produce a solid 64-by-103-nanometre rectangle, but Wei and his team can create more complex shapes by leaving out specific tiles. Using this strategy, they created 107 two-dimensional shapes, including letters, numbers, Chinese characters, geometric shapes and symbols. They also produced tubes and rectangles of different sizes, including one consisting of more than 1,000 tiles. Their work is published in Nature.

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Distant Planets, Protein Folding, and Esoteric Mathematics Net Shaw Prizes

from ScienceInsider

The discovery of trans-Neptune bodies, breakthroughs in understanding protein folding, and pioneering work in a mathematical technique known as deformation quantization have won this year's Shaw Prizes in, respectively, the categories of astronomy, life science and medicine, and mathematical sciences. The prizes, which include $1 million cash in each category, were announced yesterday in Hong Kong.

David Jewitt of the University of California, Los Angeles, and Jane Luu, of Massachusetts Institute of Technology in Cambridge share the astronomy prize for discovering and characterizing trans-Neptune bodies, or those objects in the solar system orbiting just beyond Neptune. Virtually unknown until their joint discovery in 1992 by Jewitt and Luu, these 1200 or so objects are relics of the formation of the solar system and supply short-period comets.

Protein folding is at the heart of many cellular functions. Franz-Ulrich Hartl, of the Max Planck Institute of Biochemistry in Martinsried, Germany, and Arthur Horwich of Yale University--first as a team and then independently--studied the role of "chaperones" in guiding protein folding in vitro and in vivo. Their work has helped to explain normal protein folding as well as what goes wrong in cystic fibrosis, Alzheimer's and Huntington's diseases.

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Trials Overlook Cancer Spread

from the Scientist (Registration Required)

When people die from breast cancer, it is mostly because their original tumours have metastasized to other organs. However, clinical trials for cancer drugs are focused on shrinking existing tumors, not preventing cancer spread. According to Patricia Steeg from the National Cancer Institute, this emphasis is stifling the discovery of chemicals that could prevent metastasis--costing money and patient lives.

In a comment piece, published in Nature, Steeg calls on the US Food and Drug Administration (FDA) to usher in a new type of randomized clinical trial that will demonstrate if drugs could stop breast cancer from spreading.

Animal studies have identified several compounds could potentially prevent metastasis, but these chemicals often do not kill cancer cells or tumors that have already spread. When they make it to phase II clinical trials, which are designed to test their effectiveness, they fail to shrink established tumors and are no longer pursued as potential cancer treatments. As Steeg wrote in her piece, "the drug company loses the money invested in development; the scientists who worked on these compounds lose a potentially valid clinical lead compound; and the patients continue to lose their lives."

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To Save Some Species, Zoos Must Let Others Die

from the New York Times (Registration Required)

ST. LOUIS -- With fluorescent yellow eyes and tufts of hair sticking straight up behind their ears, Bonner and Etienne look like slightly crazed old men. These riotous and chatty lemurs--known for elaborate rituals that include grooming and braying--once ranged across eastern Madagascar.

Now scores of these black-and-white ruffed lemurs are being bred here at the St. Louis Zoo and at other zoos across the United States as part of a broader effort to prevent their extinction.

But Ozzie, a lion-tailed macaque, will never father children. Lion-tails once flourished in the tops of rain forests in India, using their naturally dark coloring to disappear into the height of the jungle. Though there are only about 4,000 remaining in the wild, not one among Ozzie's group here in St. Louis will be bred. American zoos are on the verge of giving up on trying to save them.

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Falling Stout Bubbles Explained

from BBC News Online

Irish mathematicians may have solved the mystery of why bubbles in stout beers such as Guinness sink: it may simply be down to the glass. Simulations suggest an upward flow at the glass's centre and a downward flow at its edges in which the liquid carried the bubbles down with it.

But the reasons behind this flow pattern remained a mystery. Now a study on the Arxiv server reports simulations and experiments showing the standard glass' shape is responsible.

Many stout beers contain nitrogen as well as the carbon dioxide that is present in all beers. Because nitrogen is less likely to dissolve in liquid, that results in smaller and longer-lasting bubbles. But it is the sinking bubble that has confounded physicists and mathematicians alike for decades.

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Transit of Venus: Measuring the Heavens in the 18th Century

from the Guardian (UK)

The 1761 transit of Venus was a watershed moment in the history of astronomy. It was the first time astronomers would have the opportunity to measure accurately the size of the solar system. The distance between the Earth and the Sun had been estimated, with variable degrees of success, since the Greeks, but this was different.

Thanks to a rare celestial alignment, Venus was to pass in front of the Sun, taking about six hours to cross the fiery disc. By recording the times of the start and end of the event from widely separated locations around the globe, trigonometry could be used to calculate the distance to Venus and the Sun. With that, Kepler's laws of planetary motion could be used to calculate the orbits of all the planets out to Saturn, the outermost known planet.

For societies that were still struggling with inadequate maps of their own countries, it was an unimaginable leap forward.

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Climate Skepticism Not Rooted in Science Illiteracy

from Science News

People who strongly resist data indicating that human-induced climate change could spell catastrophe aren't ignorant about science or numerical reasoning. Quite the opposite, a new study finds: High science literacy actually boosts the likelihood that certain people will challenge what constitutes credible climate science.

Who will be receptive to climate science, the study found, depends more on cultural factors such as attitudes toward commerce, government regulation and individualism than on scientific literacy. "Simply improving the clarity of scientific information will not dispel public conflict" over climate, the study's authors conclude online May 27 in Nature Climate Change.

There has been a prevalent view among scientists that skeptics of climate change and its ramifications would come around if they understood the facts, says Dan Kahan of Yale Law School. But studies by his group and others have shown that cultural factors can strongly influence what people accept as truth about certain technical issues.

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Evidence of Stone Age 'Inequality'

from BBC News Online

A study of more than 300 Neolithic skeletons suggests evidence of "hereditary inequality" among farmers 7,000 years ago, researchers claim. Archaeologists from Cardiff University led a team who studied the skeletons from across Europe. They say evidence suggests farmers buried with tools had access to better land than those buried without.

Dr Penny Bickle, of Cardiff University, said community diversity "probably occurred through inheritance." The research was conducted by archaeologists from Cardiff, Bristol and Oxford universities, and others across Europe.

The project was led by Professor Alasdair Whittle from Cardiff University's school of history, archaeology and religion, and involved studying more than 300 skeletons across central Europe. The researchers claim to have evidence which suggests "differential land use among the first farmers of Europe, called the Neolithic period."

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Soft-Shell Lobsters So Soon? It's a Mystery in Maine

from NPR

April and May are fairly quiet times for Maine lobstermen and women, with the height of the summer season still a couple of months away. This year, strange things are happening on the ocean floor. Many of the lobsters have prematurely shed their hard shells, and lobstermen are hauling large numbers of soft-shelled lobsters much earlier than usual.

"That is definitely not normal," says Steve Train, who's been hauling traps for 35 years in Casco Bay, near Portland. He usually sees hard-shell lobsters at this time of year, instead of these "shedders"--lobsters that have abandoned their old casing to grow into a new, hard one.

This year, many lobstermen began catching shedders in April--four to six weeks ahead of the normal time. Train says they're outnumbering hard-shell lobsters about two to one in his traps, and he's puzzled. "We didn't expect them," he says. "I don't know if they'll be there next haul. We might go out next week and they'll be gone." The early shed surprised biologists, too.

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No New Neurons for Smell?

from ScienceNOW Daily News

Do our brains continue to produce neurons throughout our lifetimes? That's been one of the most hotly debated questions in the annals of science. Since the 1950s, studies have hinted at the possibility, but not until the late 1990s did research prove that the birth of new neurons, called neurogenesis, goes on in the brains of adult primates and humans.

Now a surprising new study in humans shows that in the olfactory bulb--the interface between the nose and the brain and an area long known to be a hot spot of neurogenesis--new neurons may be born but not survive. The finding may rule out neurogenesis in this area, or it might show only that some people don't stimulate their brains enough through the sense of smell, some researchers say.

Previous studies have found evidence of neurogenesis in the olfactory bulb of adult humans. But those studies measured only proteins produced by immature neurons, leaving open the question of whether these youngsters ever grew up to connect with other cells to form functional networks, says neuroscientist Jonas Frisén of the Karolinska Institute in Stockholm. If new olfactory neurons really reached adulthood throughout a person's life, researchers should find neurons of a variety of ages in this region.

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Blue Light Tells Plants When to Flower

from Science News

As the days become longer in spring, plants know to bloom thanks to an interaction between several crucial proteins and blue light, scientists report in the May 25 Science. The new work describes the molecular mechanics that enables a light-sensitive protein to help switch on a suite of genes that control flowering. Understanding the biology of how plants regulate flowering could be useful for tweaking crops to start producing food earlier in the year.

"We might be able to grow three times or twice as much in a season," says study coauthor Takato Imaizumi, a molecular biologist at the University of Washington in Seattle.

Generally, plants need to start blooming around the time when most pollinating insects will be buzzing around--such as in early spring--to maximize their chances of reproducing. Scientists have known that plants have higher levels of the blue-light sensitive protein FKF1 toward the end of the day and that the protein is important for tracking day length. It's also been shown that another protein, called CO, plays a key role in turning on flowering genes.

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