from the Guardian (UK)
The first plants to take root on dry land may have cooled the Earth enough to bring on a
series of ice ages, scientists claim. As plants spread across the continents, they extracted
minerals from the rocks they clung to and drew down levels of atmospheric carbon, causing
temperatures to drop markedly, the researchers say.
The scenario explains puzzling glaciations that saw ice sheets advance in the Ordovician
period between 488m and 444m years ago. At the time, Earth's continents were clustered over the
South Pole and stretched as far north as the equator.
Writing in the journal Nature Geoscience, a team led by Timothy Lenton at Exeter
University describes experiments to investigate the environmental impact of Earth's first land
plants. They took rocks and covered some with moss to mimic the simple plant life that thrived in
the Ordovician, then incubated them for three months.
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from Nature News
Over the years, Robert Daum has learned to respect his adversary. In 1995, he and his
co-workers at the University of Chicago children's hospital in Illinois were investigating
infections that had affected two dozen children in their emergency department.
Three children had fast-moving pneumonia. A fourth had an abscess the size of his fist buried
in the muscle of one buttock. In a fifth, the bacterium had infiltrated the bones of one foot.
The infections were resistant to many common antibiotics, including methicillin. To Daum's
surprise, the culprit was MRSA--methicillin-resistant Staphylococcus aureus--a bacterium that was
thought to spread only among hospital inpatients.
But none of these kids had been to the hospital for months before becoming ill. Few
researchers were willing to accept the implications. Daum wrangled for 18 months with editors at
the Journal of the American Medical Association over a paper reporting the cases and
showing that this strain was dangerous, acquired in the community and differed genetically from
hospital strains.
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from ScienceNOW
Massage's healing touch may have more to do with DNA than with good hands. A new study has
revealed for the first time how kneading eases sore muscles--by turning off genes associated with
inflammation and turning on genes that help muscles heal. The discovery contradicts popular
claims that massage squeezes lactic acid or waste products out of tired muscles and could bring
new medical credibility to the practice.
Despite massage's widespread popularity, researchers know surprisingly little about its
effects on muscles. Past studies have managed to show only that a well-administered rub can
reduce pain, but none has ever pinpointed how. The scant evidence makes many physicians unsure,
if not outright skeptical, of the method.
Mark Tarnopolsky, a neurometabolic researcher at McMaster University in Hamilton, Canada, was
one of those physicians--until he suffered a severe hamstring injury in a waterskiing accident 4
years ago. Massage therapy was part of his rehabilitation regimen, and it was so effective at
easing his pain that he became determined to track down the mechanism that made him feel so good.
"I thought there has to be a physiologic basis for this," he says. "And being a cellular
scientist, my interest's in the cellular basis."
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from ScienceNOW
Sebastian the crab may have been wrong about the deep sea. In Disney's The Little
Mermaid, the orange crustacean famously touted the tranquility of life well below the waves,
singing "it's better down where it's wetter." But the ocean's depths can get stormy, too,
researchers say. New observations taken from a canyon in the Mediterranean Sea during an epic
storm reveal that surface weather can shake up even the bottom-most ocean habitats.
Of course, it was one big storm. The gale pounded the coast of northeast Spain on 26 December
2008, with winds hitting speeds of more than 70 kilometers per hour, while waves topped off over
10 meters high. In all, residents hadn't seen a tempest that fierce in at least 25 years.
And marine habitats took a beating, too. The storm, for instance, whipped up sand and silt
along shallow waters, burying many sea grass beds that are home to a range of fish,
invertebrates, and other organisms, and scouring countless others. Still, whether such a squall
could shake up marine communities in deeper water--such as in Blanes Canyon, which juts from the
Spanish coast and plumbs depths of up to 1500 meters--hadn't been clear.
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from Science News
Long-slumbering volcanoes can jolt to life faster than students drinking Red Bull, a new study
suggests.
Studies of millennia-old rocks that erupted at Santorini, Greece, show that the chemical
composition of its magma changed just a few decades before the volcano blew its top around 1600
B.C. That blast came after 18,000 years of relative calm.
"All this happens at a very late stage relative to this long period of repose," says Tim
Druitt, a volcanologist at the Blaise Pascal University in Clermont-Ferrand, France. "There's
kind of a rapid wake up."
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from National Geographic News
Last week NASA's Kepler mission added 26 new planets in 11 star systems to the roster of
confirmed extrasolar planets, or exoplanets. The find tripled the number of known planet systems
with multiple worlds that transit--or pass in front of--their stars.
Now, a new study based on Kepler data says that such multiplanet hauls will become more
common, because multiple-planet systems are much less likely than single candidates to turn out
to be false positives.
"What we are finding is that, if you see more than one planet candidate in a system, then it's
really likely that those are all real planets," said study co-author Elisabeth Adams, an
astronomer at the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Massachusetts.
"So, of the 170 systems that Kepler has found with multiple planet candidates"--representing a
total of 408 possible planets--"probably all but one or two of the planets are real."
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from the San Francisco Chronicle
Federal regulators Monday approved the first drug for people with advanced forms of basal cell carcinoma, the most common kind of skin cancer, as well as the most common cancer in general in the United States.
The drug, made by South San Francisco's Genentech, a subsidiary of the Swiss drug giant Roche, is designed for patients whose basal cell cancer has spread either locally or to other parts of the body.
Basal cell carcinoma, which forms in the lower part of the outer layer of the skin or epidermis, affects some 2 million Americans each year. While basal cell carcinoma is rarely fatal and is generally considered curable, in a small percentage of patients it can spread and in some cases cannot be treated with surgery or other methods. The U.S. Food and Drug Administration approved the drug, which is called Erivedge, after an expedited six-month review in advance of the March 8 approval deadline.
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from New Scientist
"A better, richer and happier life for all our citizens." That's the American dream. In practice, it means living in a spacious, air-conditioned house, owning a car or three and maybe a boat or a holiday home, not to mention flying off to exotic destinations.
The trouble with this lifestyle is that it consumes a lot of power. If everyone in the world started living like wealthy Americans, we'd need to generate more than 10 times as much energy each year. And if, in a century or three, we all expect to be looked after by an army of robots and zoom up into space on holidays, we are going to need a vast amount more. Where are we going to get so much power from?
It is clear that continuing to rely on fossil fuels will have catastrophic results, because of the dramatic warming effect of carbon dioxide. But alternative power sources will affect the climate too. For now, the climatic effects of "clean energy" sources are trivial compared with those that spew out greenhouse gases, but if we keep on using ever more power over the coming centuries, they will become ever more significant.
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from Nature News
Informing clinical-trial participants of the risks they face is a cornerstone of modern medical research, and it is enshrined as a human right in international codes of ethics. But an influential group of ethicists and medical researchers warned at a meeting in Brussels last week that the process has become a box-ticking exercise focused more on offering legal protection to a trial's organizer than actually protecting patients.
"We clearly identified there is an urgent need to do informed consent better," says Ingrid Klingmann, chairman of the European Forum for Good Clinical Practice, a think tank based in Brussels and the organizer of the meeting. "The pressure is really huge on all those involved to better enable patients to understand the implications of their study participation, their benefits, risks and obligations."
The European Clinical Trials Directive, which sets minimum standards for clinical trials conducted in the European Union's member states, says that trial participants must be duly informed of the "nature, significance, implications and risks" of the clinical trial. Yet delegates at the meeting detailed a host of ways in which the system fails to meet those criteria.
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from BBC News Online
Non-native Burmese pythons are the likely cause of a dramatic mammal decline in Florida's Everglades. A team studied road surveys of mammals in the Everglades National Park before and after pythons became common.
Researchers found a strong link between the spread of pythons and drops in recorded sightings of racoons, rabbits, bobcats and other species. In PNAS journal, they report that observations of several mammal species have declined by 90% or more.
The national park covers the southern 25% of the original Everglades--a region of subtropical wetlands that has been drained over the last century to reclaim it for human use. The origins of Burmese pythons in south Florida are unknown, but many were imported into the US through the pet trade.
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from the Seattle Times
CHICAGO (Associated Press) -- Officials are investigating the events surrounding a power failure at a nuclear reactor in northern Illinois, but believe they may have traced the cause to a piece of equipment at a switchyard.
After the shutdown Monday morning at Exelon Nuclear's Byron Generating Station, operators began releasing steam to cool the reactor from the part of the plant where turbines produce electricity, not from within the nuclear reactor itself, officials said. The steam contains low levels of tritium, a radioactive form of hydrogen, but federal and plant officials insisted the levels were safe for workers and the public.
Exelon Nuclear officials believe a failed piece of equipment at a switchyard at the plant about 95 miles northwest of Chicago caused the shutdown, but they were still investigating an exact cause. The switchyard is similar to a large substation that delivers power to the plant from the electrical grid and from the plant to the electrical grid.
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from the Christian Science Monitor
The Isthmus of Tehuantapec, Mexico's narrowest point, is a powerful wind tunnel of air currents whipping through the mountains that separate the Pacific and Atlantic oceans.
Here, on the Pacific side, the wind shapes everything from the miles-long sandspits of Laguna Superior to the landscapes of the indigenous people's hearts.
Howling constantly through thatched roofs, the wind is powerful enough at times to support a grown man leaning back as if in a chair. Gales average 19 miles per hour, slapping waves over the bows of fishing skiffs and sandblasting anyone standing on the beach.
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from the Pittsburgh Post-Gazette
The tip of a girl's 40,000-year-old pinky finger found in a cold Siberian cave, paired with faster and cheaper genetic sequencing technology, is helping scientists draw a surprisingly complex new picture of human origins. The new view is fast supplanting the traditional idea that modern humans triumphantly marched out of Africa about 50,000 years ago, replacing all other types that had gone before.
Instead, the genetic analysis shows, modern humans encountered and bred with at least two groups of ancient humans in relatively recent times: the Neanderthals, who lived in Europe and Asia, dying out roughly 30,000 years ago, and a mysterious group known as the Denisovans, who lived in Asia and most likely vanished around the same time.
Their DNA lives on in us even though they are extinct. "In a sense, we are a hybrid species," Chris Stringer, a paleoanthropologist who is the research leader in human origins at the Natural History Museum in London, said in an interview.
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from Nature News
"The race is on for positions in the new oil provinces." That starting-gun quote was fired last week by Tim Dodson, executive vice-president of the Norwegian oil and gas company Statoil. The 'new oil provinces' are in the Arctic, which brims with untapped resources amounting to 90 billion barrels of oil, up to 50 trillion cubic metres of natural gas and 44 billion barrels of natural gas liquids, according to a 2008 estimate by the US Geological Survey. That's about 13% of the world's technically recoverable oil, and up to 30% of its gas--and most of it is offshore.
Oil companies see an opportunity to sate the world's demand for fossil fuels. Green groups and many scientists, however, are horrified by the prospect of drilling and production in remote, often ice-choked waters, where spills would be harder to control and clean up than in warmer regions. Memories of the devastating environmental impact of the Exxon Valdez accident in 1989 in Alaska's Prince William Sound are still all too fresh--like the oil that can still be found in the area's beaches.
At last week's Arctic Frontiers conference in Tromsø, Norway, the oil industry insisted that it will be cautious and responsible in extracting oil and gas in the region, and it rolled out an initiative to develop ways of coping with any accidents. Dodson told the meeting that "technology will be there to clean it up."
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from National Geographic News
On an island off Britain's northern tip, new discoveries suggest a huge Stone Age ritual complex is older than Stonehenge. But age is only the half of it. Researchers say the site may have in fact been the original model for Stonehenge and other later, better-known British complexes to the south.
First discovered in 2002, the waterside site--called the Ness of Brodgar ("Brodgar promontory")--lies on Mainland, the largest of Scotland's Orkney Islands.
According to recent radiocarbon dating of burned-wood remains, the Ness was first occupied around 3200 B.C. and went on to include up to a hundred buildings within a monumental walled enclosure. By contrast, the earliest earthworks at Stonehenge date to about 3000 B.C. And it would be roughly another 500 years before the first of the famous stones were set on Salisbury Plain.
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from the Scientist (Registration Required)
Many mouse studies have shown that radiation treatment can cause germline mutations, which can then be passed onto subsequent generations. Now, new research in mice takes this idea one step further: this mutagenic environment can be transferred from sperm to eggs upon fertilization, doubling the mutations in the resulting embryos.
The study, published today (January 30) in the Proceedings of the National Academy of Sciences, raises health concerns for children of young cancer survivors, most of whom have been through multiple rounds of radiation treatment. "This result is now so solid that I think we can't ignore it," said radiologist Keith Baverstock from the University of Eastern Finland, who was not involved in the research. "It is an important result because these drugs and radiation are all we really have to treat cancer."
Baby mice sired by fathers exposed to any of a variety of radiation types--chemical, ionizing, and chemotherapeutic--all have a far higher mutation rate than expected by chance. "The children of irradiated mice are unstable," said Yuri Dubrova, a geneticist at the University of Leicester "They show quite high rate by which mutations occur in the germ cells, egg and sperm, and same is true for their somatic cells."
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from National Geographic News
Clouds of "cold plasma" reach from the top of Earth's atmosphere to at least a quarter the distance to the moon, according to new data from a cluster of
European satellites. Earth generates cold plasma--slow-moving charged particles--at the edge of space, where sunlight strips electrons from gas atoms,
leaving only their positively charged cores, or nuclei.
Researchers had suspected these hard-to-detect particles might influence incoming space weather, such as this week's solar flare and resulting geomagnetic
storm. That's because solar storms barrage Earth with similar but high-speed charged particles.
Still, no one could be certain what the effects of cold plasma might be without a handle on its true abundance around our planet.
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from BBC News Online
The Little Ice Age was caused by the cooling effect of massive volcanic eruptions, and sustained by changes in Arctic ice cover, scientists conclude.
An international research team studied ancient plants from Iceland and Canada, and sediments carried by glaciers.
They say a series of eruptions just before 1300 lowered Arctic temperatures enough for ice sheets to expand. Writing in Geophysical Research
Letters, they say this would have kept the Earth cool for centuries.
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from the Guardian (UK)
Five thousand metres above the most biodiverse corner of the Amazon, tropical ecologist Greg Asner and his team see a kaleidoscope of colours among a mass
of green.
Huddled in a twin-engine Dornier 228 aeroplane called the Carnegie Airborne Observatory, the scientists are capturing multicoloured images of the Peruvian
rainforest canopy that verge on the psychedelic.
Inside the plane, a machine known as a Lidar (Light Detection and Ranging) bounces a laser beam off the forest canopy 400,000 times per second--the result
is a three-dimensional map of the forest showing unprecedented detail.
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from the Pittsburgh Post-Gazette
WASHINGTON -- There's no firm date yet, but sometime in early 2014 NASA intends to take its first major step toward rebuilding its human spaceflight
program. The milestone is the maiden test flight of its Orion spacecraft, a launch that has come into sharper relief in the three months since NASA and
manufacturer Lockheed Martin announced it.
As planned, an unmanned Orion capsule will begin its journey at Cape Canaveral and take two loops around Earth before splashing down in the Pacific Ocean.
What's now clear is that the capsule will be sent far beyond the lower Earth orbit of the International Space Station.
At its peak, Orion's orbit is expected to extend nearly 3,700 miles from Earth--the farthest a NASA spacecraft built for humans has gone since the early
1970s.
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from Nature News
The publication of a paper denying the link between HIV and AIDS in an Italian anatomy journal has prompted a member of its editorial board to resign in
protest.
Klaudia Brix, a cell biologist at Jacobs University in Bremen, Germany, says that she tendered her resignation from the board of the Italian Journal of
Anatomy and Embryology (IJAE) because she felt that it was important for a journal to function within its scientific "scope."
Others on the 13-member board have also raised concerns. Hanne Mikkelsen, a professor of molecular medicine at the University of Copenhagen, Denmark, says
that she too is considering resigning her position.
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from ScienceNOW Daily News
Two years ago, physicists fired up the world's first laser to shine out hard x-rays--the high-energy, short-wavelength particles of light needed to probe
atomic-scale structure. Shining 10 billion times brighter than any previous x-ray source, the Linac Coherent Light Source (LCLS) can determine the structure
of crystals from samples a few nanometers across and probe changes in materials that take place in a millionth of a nanosecond.
But the $410 million LCLS doesn't look anything like a laser pointer, as it relies on a 3-kilometer-long particle accelerator to generate x-rays. Now,
physicists have made a much smaller x-ray laser that works much more like the conventional one you might carry around in your pocket.
The new atomic x-ray laser won't replace the LCLS and other accelerator-based systems. In fact, to make the atomic laser work, researchers blasted neon
atoms with x-rays from the LCLS itself. Still, the results mark a conceptual triumph, fulfilling a 45-year-old prediction that such an atomic x-ray laser is
possible. "Nobody had done this before, and everybody knew that somebody had to go out and do this," says Philip Bucksbaum, director of SLAC's PULSE
Institute for Ultrafast Energy Science in Menlo Park, California, who was not involved in the work. "So this is great."
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from New Scientist
Stressed yeast cells frantically reshuffle their chromosomes in a desperate last bid to find a combination that survives. This "panic" response enables
them to rapidly evolve resistance to drugs.
The discovery might also apply to cancer, because cancer cells often have abnormal numbers and arrangements of chromosomes. Understanding one of the
mechanisms by which cancers develop resistance to drugs could in turn open up new ways to combat cancer.
The key panic button driving the reshuffling is heat-shock protein 90 (Hsp90), which normally ensures that chromosomes are faithfully copied when cells
divide and multiply. When Hsp90 is knocked out, the chromosomes get completely reshuffled. That's normally a disaster, but in a desperate situation it's a
potential lifeline.
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from Spiegel
It took a tall ladder and weeks of training, but an elephant at Amsterdam's Artis Zoo has become the first of her species in Europe to be fitted with a
contact lens.
Win Thida, a 45-year-old Asian elephant, suffered a scratched cornea during a tussle with another elephant. Her eye started watering and she had trouble
keeping it open, so the zoo called in veterinarian Anne-Marie Verbruggen.
Verbruggen had experience fitting horses with contacts, but it was her first attempt on an elephant. "The main difficulty was her height," Verbruggen told
the Irish Times. "Elephants can't lie down for long before their immense weight impairs their breathing, so I used a ladder to get close enough. It wasn't
ideal, but it worked. She seemed happier straight away."
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from the Los Angeles Times (Registration Required)
Salinas, Calif. -- For millions of Americans, bagged salads are a miracle food, the perfect mix of health and convenience. Time-pressed cooks can rip open
a bag and pour the leaves right into the bowl, reassured by the "triple-washed" label that some wondrous process has rendered these greens squeaky clean and
ready for dinner.
They don't want to think about E. coli O157:H7. And the salad industry doesn't want them thinking about it either.
That's why the safety of bagged greens has emerged as one of the most pressing issues in today's fresh produce business. It's why industry and government
are investing millions to avoid debacles such as the death of 30 people last year after eating poorly washed, listeria-laced cantaloupe.
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from the New York Times (Registration Required)
BEIJING -- Weary of waiting for the authorities to alert residents to the city's most pernicious air pollutant, citizen activists last May took matters
here into their own hands: they bought their own $4,000 air-quality monitor and posted its daily readings on the Internet.
That began a chain reaction. Volunteers in Shanghai and Guangzhou purchased monitors in December, followed by citizens in Wenzhou, who are selling oranges
to finance their device. Wenzhou donated $50 to volunteers in Wuhan, 140 miles inland. Officials have claimed for years that the air quality in fast-growing
China is constantly improving. Beijing, for example, was said to have experienced a record 274 "blue sky" days in 2011, a statistic belied by the heavy smog
smothering the city for much of the year.
But faced with an Internet-led brush fire of criticism, the edifice of environmental propaganda is collapsing. The government recently reversed course and
began to track the most pernicious measure of urban air pollution--particulates 2.5 microns in diameter or less, or PM 2.5. It decreed that about 30 major
cities must begin monitoring the particulates this year, followed by about 80 more next year.
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Some areas could find global warming beneficial. Countries that are cold right now could see very real benefits from a few extra degrees. Consider the Northern Sea shipping route, which runs through the Arctic waters north of Europe and Asia. Climate change could open the route earlier and keep it clear later.
In other environmental news, Duke University scientists are among those studying plants for biofuel. GrassRoots Biotechnology uses patented research methods to study plant genes. The goal, said company co-founder Philip Benfey, is to pinpoint ways to strengthen plants considered useful in biofuel production, such as switchgrass.
In a related development, new research "makes a pretty large leap forward" in the quest to make seaweed a viable biofuel. Researchers have engineered a bacterium that can break down and digest seaweed's gummy cell walls to yield ethanol and other useful compounds.
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