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A Regime's Tight Grip on AIDS

from the New York Times (Registration Required)

HAVANA -- Yudelsy García O'Connor, the first baby known to have been born with H.I.V. in Cuba, is not merely still alive. She is vibrant, funny and, at age 25, recently divorced but hoping to remarry and have children.

Her father died of AIDS when she was 10, her mother when she was 23. She was near death herself in her youth. "I'm not afraid of death," she said. "I know it could knock on my door. It comes for everyone. But I take my medicine."

Ms. García is alive thanks partly to lucky genes, and partly to the intensity with which Cuba has attacked its AIDS epidemic. Whatever debate may linger about the government's harsh early tactics--until 1993, everyone who tested positive for H.I.V. was forced into quarantine--there is no question that they succeeded.

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Was Ancient Crocodile World's Largest?

from the Christian Science Monitor

Scientists have announced the discovery of a newfound crocodile species that may have been the largest to ever roam the Earth. The colossal reptiles trolled East African waters between 4 million and 2 million years ago, and may have snacked on human ancestors, researchers said.

The largest fossil specimens recovered belong to massive crocodiles some 25 feet (7.5 meters) in length; and the ancient giants may have grown larger than 27 feet (8 meters), according to Christopher Brochu, an associate professor of geosciences at the University of Iowa.

Brochu stumbled upon the new species three years ago, while examining enormous fossils housed at the National Museum of Kenya in Nairobi. It took four men to lift the skull of one of the specimens, which were originally excavated from the Turkana Basin, an area surrounding Lake Turkana in northern Kenya.

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No End to Obesity Epidemic, 20-Year Forecast Shows

from ABC News

(Associated Press) - The obesity epidemic may be slowing, but don't take in those pants yet. Today, just over a third of U.S. adults are obese. By 2030, 42 percent will be, says a forecast released Monday.

That's not nearly as many as experts had predicted before the once-rapid rises in obesity rates began leveling off. But the new forecast suggests even small continuing increases will add up.

"We still have a very serious problem," said obesity specialist Dr. William Dietz of the Centers for Disease Control and Prevention. Worse, the already obese are getting fatter. Severe obesity will double by 2030, when 11 percent of adults will be nearly 100 pounds overweight, or more, concluded the research led by Duke University.

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Sierra Nevada Mountains Still Reaching for the Sky

from the San Francisco Chronicle

The mountains of the Sierra Nevada are still rising, and they're a lot younger than most scientists previously thought.

That's the conclusion of Earth scientists in Nevada who have used space-based radar and the most advanced GPS measurements to conclude that the entire range is now rising at a rate of one to two millimeters a year--less than an inch a decade--and in its modern form could be less than 3 million years old.

And scientists who have long held very different views about the age of the Sierra Nevada concede the mountains may have undergone a more recent pulse of upward growth, but still maintain they reached their present height many millions of years ago.

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Tidal Heating Shrinks the 'Goldilocks Zone'

from Nature News

A previously little-considered heating effect could shrink estimates of the habitable zone of the Milky Way's most numerous class of stars--'M' or red dwarfs--by up to one half, says Rory Barnes, an astrobiologist at the University of Washington in Seattle. That factor--gravitational heating via tides--suggests a menagerie of previously undreamt-of planets, on which tidal heating is a major source of internal heat. Barnes presented the work yesterday at a meeting of the American Astronomical Society's Division on Dynamical Astronomy in Timberline Lodge, Oregon.

The habitable zone is the orbital region close enough to a star for a planet to have liquid water, but not so close that all of the water evaporates. For our Sun, the zone extends roughly from the inner edge of the orbit of Mars to the outer edge of that of Venus. For smaller, cooler stars, such as M-class dwarfs, the zone can be considerably closer to the star than Mercury is to the Sun. And because close-in planets are easier to spot than more distant ones, such stars have been a major target for planet hunters seeking Earth-like worlds.

There's just one problem with finding habitable planets around such stars, says Barnes. Because tidal forces vary dramatically with the distance between a planet and its star, closer orbits also result in massively larger tidal forces.

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Herd's Fate Lies in Preservation Clash

from the New York Times (Registration Required)

COROLLA, N.C. -- Come summer, the beaches of this barrier island will be choked with cars and sunbathers, but in the off-season the land is left to wild horses. Smallish, tending toward chestnut and black, they wander past deserted vacation rentals in harems of five or six.

Thousands of them once roamed the length of the Outer Banks of North Carolina, the likely descendants from mounts that belonged to Spanish explorers five centuries ago. Now their numbers have dwindled to a few hundred, the best known living on federal parkland at Shackleford Banks.

But the largest herd, which has recently grown to almost 140 strong, occupies more than 7,500 acres of narrow land that stretches from the end of Highway 12 in Corolla (pronounced cor-AH-la) to the Virginia border, 11 miles north. Lacking natural predators, and trapped by fences that jut into the choppy Atlantic, the herd is becoming so inbred that its advocates fear a genetic collapse in mere generations.

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Gaia Creator Rows Back on Climate

from BBC News Online

The scientific maverick James Lovelock says climate catastrophe is not so certain as he previously suggested. Dr Lovelock, one of the world's leading environmental thinkers, once warned climate change would reduce mankind to a few breeding pairs in the Arctic.

On BBC Radio 4's The Life Scientific he gave credit to scientists who question the inevitability of conclusions from climate change computer models. But he maintained it was probably too late to stop climate change.

He warned: "We are moving in a direction which won't do humanity any good at all if we just go on doing it." His double-edged message was that the planet would "heal itself" from an overdose of greenhouse gases--but probably over millions or tens of millions of years.

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FDA Favors First Drug for HIV Prevention

from the Seattle Times

WASHINGTON (Associated Press) -- Federal drug regulators on Tuesday affirmed landmark study results showing that a popular HIV-fighting pill can also help healthy people avoid contracting the virus that causes AIDS in the first place. While the pill appears safe and effective for prevention, scientists stressed that it only works when taken on a daily basis.

The Food and Drug Administration will hold a meeting Thursday to discuss whether Truvada should be approved for people who are at risks of contracting HIV through sexual intercourse. The agency's positive review posted Tuesday suggests the daily pill will become the first drug approved to prevent HIV infection in high-risk patients.

FDA reviewers conclude that taking Truvada pre-emptively could spare patients "infection with a serious and life-threatening illness that requires lifelong treatment."

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Cosmic Blasts Powered by a Hot Glow

from Nature News

Since its launch in 2008, the Fermi space telescope has recorded hundreds of gamma-ray bursts (GRBs), flashes of light that, for just a few seconds or minutes, are the brightest objects in the Universe. And now the telescope is yielding data that is starting to explain the mechanisms that unleash these beam-like jets of light, which are thought to emanate from the poles of a spinning star as it collapses to form a black hole and explode in a supernova.

On 7 May, at the 2012 meeting of the Fermi/Swift GRB conference in Munich, Germany, members of the Fermi team showed evidence that the gamma rays were not being generated through the commonly invoked process of synchrotron radiation, where electrons emit light as they are accelerated in shockwaves rippling out from the explosion.

Instead, most of the light is coming from a seemingly more obvious place: originating in thermal emissions at the surface of the fireball. Just as the Sun's yellow light emanates from its photosphere (the surface region from which the externally perceived light of a star originates), so too are the GRBs arising mostly as thermal emissions from the photosphere of a fireball expanding at the speed of light.

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Traces of Inaugural Life

from Science News

Earth's first living organisms didn't leave behind footprints or bite marks or bones. These single cells thrived quietly in a tiny pocket somewhere on the planet. For centuries, scientists trying to describe this earliest life have relied on evidence provided by biology, studying what features modern life-forms have in common to deduce the most primitive components of cells.

By working backward, biologists have developed proposals describing when and where such simple forms of life could have arisen. But the ideas so far are guesses at best, impossible to prove.

Researchers from a different field--geology--have more recently joined in the effort. With guidance from biologists, geologists are looking to Earth's oldest rocks to uncover traces of life left behind by the very first cells. Geologists are also pointing biologists toward unusual environments where early cells might have gained a foothold. Where the two fields intersect, more concrete scenarios regarding life's formative years are now taking shape.

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Scientists Drill into Clear Lake to See Future

from the San Francisco Chronicle

Drilling deeply into ancient sediments beneath Clear Lake, UC Berkeley scientists are seeking vital clues to the future of plant and animal life by investigating how changing climates have altered life in the distant past.

The drilling will end next week, and then the 17 scientists on the project will begin analyzing thousands of tiny pollen grains brought up in drill cores from far beneath the lakebed to learn how plant species large and small met the challenge of survival during past periods of climate change.

Significant episodes of global warming--and cold waves, too--hit the Earth many thousands of years ago, leaving records of the past. Those records, in microscopic bits of plant matter, make up the evidence the researchers will study.

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Human Brain Shaped by Duplicate Genes

from Nature News

Humans walk on two feet and (mostly) lack hair-covered bodies, but the feature that sets us furthest apart from other apes is a brain capable of language, art, science, and other trappings of civilisation.

Now, two studies published online today in Cell suggest that DNA duplication errors that happened millions of years ago might have had a pivotal role in the evolution of the complexity of the human brain. The duplications--which created new versions of a gene active in the brains of other mammals--may have endowed humans with brains that could create more neuronal connections, perhaps leading to greater computational power.

The enzymes that copy DNA sometimes slip extra copies of a gene into a chromosome, and scientists estimate that such genetic replicas make up about 5% of the human genome. However, gene duplications are notoriously difficult to study because the new genes differ little from their forebears, and tend to be overlooked.

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Dogs Feel Your Pain

from ScienceNOW Daily News

Yawn next to your dog, and she may do the same. Though it seems simple, this contagious behavior is actually quite remarkable: Only a few animals do it, and only dogs cross the species barrier. Now a new study finds that dogs yawn even when they only hear the sound of us yawning, the strongest evidence yet that canines may be able to empathize with us.

Besides people and dogs, contagious yawning has been observed in gelada baboons, stump-tail macaques, and chimpanzees. Humans tend to yawn more with friends and acquaintances, suggesting that "catching" someone's yawn may be tied to feelings of empathy. Similarly, some studies have found that dogs tend to yawn more after watching familiar people yawning. But it is unclear whether the canine behavior is linked to empathy as it is in people. One clue might be if even the mere sound of a human yawn elicited yawning in dogs.

To that end, scientists at the University of Porto in Portugal recruited 29 dogs, all of whom had lived for at least 6 months with their owners. To reduce anxiety, the study was performed in familiar rooms in the dogs' homes and in the presence of a known person but with no visual contact with their owners.

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When Illness Makes a Spouse a Stranger

from the New York Times (Registration Required)

He threw away tax documents, got a ticket for trying to pass an ambulance and bought stock in companies that were obviously in trouble. Once a good cook, he burned every pot in the house. He became withdrawn and silent, and no longer spoke to his wife over dinner. That same failure to communicate got him fired from his job at a consulting firm.

By 2006, Michael French--a smart, good-natured, hardworking man--had become someone his wife, Ruth, felt she hardly knew. Infuriated, she considered divorce.

But in 2007, she found out what was wrong.... Mr. French, now 71, has frontotemporal dementia--a little-known, poorly understood and frequently misdiagnosed group of brain diseases that eat away at personality and language. Although it was first recognized more than 100 years ago, there is still no cure or treatment, and patients survive an average of only eight years after the diagnosis.

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LHC Prepares for Data Pile-Up

from Nature News

The world's largest particle accelerator is roaring along at an unprecedented pace, delivering torrents of data to its physicist handlers. But the hundreds of millions of collisions happening inside the machine every second are now growing into a thick fog that, paradoxically, threatens to obscure a fabled quarry: the Higgs boson.

The problem is known as pile-up, and it promises to be one of the greatest challenges this year for scientists working on the Large Hadron Collider (LHC) at CERN, Europe's main high-energy physics laboratory near Geneva, Switzerland.

Huge amounts of computing power, cunning software and technical tricks are helping scientists to stay ahead of the problem. But researchers may still need to scale back the collisions to find the long-sought Higgs, the manifestation of a field that is believed to confer mass on other particles.

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Amid Brazil's Rush to Develop, Workers Resist

from the New York Times (Registration Required)

JACI PARANÁ, Brazil - The revolt here on the banks of the Madeira River, the Amazon's largest tributary, flared after sunset. At the simmering end of a 26-day strike by 17,000 workers last month, a faction of laborers who were furious over wages and living conditions began setting fire to the construction site at the Jirau Dam.

Throughout the night, they burned more than 30 structures to the ground and looted company stores, capturing the mayhem on their own cellphone cameras, before firefighters extinguished the blazes. The authorities in Brasília flew in hundreds of troops from an elite force to quell the unrest.

Men in camouflage fatigues still patrol the sprawling work site, reflecting a dilemma for Brazil's leaders. Even as they move to tap one of the world's last great reserves of hydroelectric power, the Amazon basin, strikes and worker uprisings at the biggest projects are producing delays and cost overruns.

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Whence the Domestic Horse

from ScienceNOW Daily News

Shards of pottery with traces of mare's milk, mass gravesites for horses, and drawings of horses with plows and chariots: These are some of the signs left by ancient people hinting at the importance of horses to their lives. But putting a place and date on the domestication of horses has been a challenge for archaeologists. Now, a team of geneticists studying modern breeds of the animal has assembled an evolutionary picture of its storied past. Horses, the scientists conclude, were first domesticated 6000 years ago in the western part of the Eurasian Steppe, modern-day Ukraine and West Kazakhstan. And as the animals were domesticated, they were regularly interbred with wild horses, the researchers say.

"This is a very good paper," says biologist Michael Hofreiter of the University of York in the United Kingdom. "Nobody has applied this method of population modeling to horses before."

Throughout their history, horses have been interbred, traded between populations of people, and moved across continents. All of this makes their genetic history hard to follow. Moreover, the wild ancestor of horses, Equus ferus, is extinct, complicating researchers' efforts to compare the genetics of domestic animals with wild ones. Previous research nailed down a broad area--the Eurasian Steppe, which stretches from Hungary and Romania through Mongolia--as the region where horses originated and were domesticated. But earlier genetic studies relied mostly on mitochondrial DNA, which is inherited only from a mother, to try to understand horses' evolutionary history.

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The Dinosaurs' Nemeses: Giant, Jurassic Fleas

from NPR

Fossil-hunting scientists are coming to grips with a new discovery that could change forever how we think of dinosaurs. What they've found is that dinosaurs may well have been tortured by large, flealike bloodsucking insects.

Yes, it appears that the greatest predators that ever roamed Earth suffered just as we mammals did--and as we still do. Fleas were thought to have evolved along with mammals--they like our soft skins and a diet of warm blood. But now scientists in China have discovered Pseudopulex jurassicus and its equally tyrannical cousin, Pseudopulex magnus--magnus as in "great."

Indeed, they were big--several times as big as current fleas-and equipped to feed. "They have this large beak," says zoologist George Poinar Jr. "Oh, it looks horrible. It looks like a syringe when you go to the doctor to get a shot or something."

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Saga of California's Salton Sea: a Tragic Chapter Ahead?

from the Christian Science Monitor

California's Salton Sea hasn't been looking too good for some time, and now environmentalists are concerned that conditions at this salty inland "sea" are about to get much worse.

Their big worry: that the body of water, created during a huge flood in 1905 in which distant Colorado River water coursed into a desert basin, will shrink much faster in coming years than it has been. As the shallow lake dries out, contaminants from decades of agricultural runoff--such as selenium and arsenic--will be exposed and, whipped by high winds, carried far afield, threatening the health of people and wildlife. Several species of migratory birds along the Pacific Flyway will also be threatened, environmentalists warn.

Why are they expecting this accelerated shriveling of the Salton Sea? A big water diversion system is slated to transfer water now used locally for farming to the south, in San Diego County, for use by city-dwellers.

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Study Finds Psychopaths Have Distinct Brain Structure

from the Baltimore Sun

LONDON (Reuters) - Scientists who scanned the brains of men convicted of murder, rape and violent assaults have found the strongest evidence yet that psychopaths have structural abnormalities in their brains.

The researchers, based at King's College London's Institute of Psychiatry, said the differences in psychopaths' brains mark them out even from other violent criminals with anti-social personality disorders (ASPD), and from healthy non-offenders.

Nigel Blackwood, who led the study, said the ability to use brain scans to identify and diagnose this sub-group of violent criminals has important implications for treatment. The study showed that psychopaths, who are characterized by a lack of empathy, had less grey matter in the areas of the brain important for understanding other peoples' emotions.

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Bird Flu Hybrid May Transmit in Humans

Controversial research on a hybrid strain of bird flu that could potentially spread between humans was published last week in Nature after security restrictions on the work were lifted. Publication was delayed after the U.S. government's biosecurity advisers said key sections of the paper should be struck out to prevent the details being exploited by bioterrorists.

In other biomedical news, a groundbreaking trial involved 43 patients who got immune cells designed to attack and kill cells infected with HIV. Scientists reported that as much as 16 years later, these genetically engineered T cells are still circulating in their bloodstreams. And there's been no sign the gene therapy caused any cancers, or is likely to.

Scientists have detected tiny amounts of a strangely shaped protein -- a relative of a well-known suspect in Alzheimer's disease -- spreading destruction throughout the brains of mice. If a similar process happens in the human brain, it could help explain how Alzheimer's starts, and even suggest new ways to stop the molecule's spread.

Researchers are hopeful that a genetic test could help predict breast cancer many years before the disease is diagnosed. Ultimately the findings, in the journal Cancer Research, could lead to a simple blood test to screen women, they say.

And the Los Angeles Times was among media outlets to report on a pair of studies that may offer some clarity on mammograms. Researchers found that women who have a mother or sister diagnosed with breast cancer, or those who have unusually dense breast tissue, should have their first test at age 40 and repeat the exam at least once every other year.

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'Pretty Basic Things' Led to September Blackout

Federal investigators reported last week that millions of people in Southern California, Arizona and northern Mexico were plunged into darkness last September because of errors and system problems paralleling those that caused the great Eastern blackout of 2003.

In other technology news, the Simons Foundation has chosen the University of California, Berkeley, as host for an ambitious new center for computer science. The foundation's $60 million grant underscores the growing influence of computer science on the physical and social sciences.

A new study has found that wind farms can cause climate change. At night the motion of the turbines mixes warmer air higher in the atmosphere with colder air nearer the surface, pushing up the overall temperature.

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Brazil Skeleton 'The Most Exciting That We've Found'

Last week the New York Times featured the work of a paleontologist who has discovered some intriguing specimens in a Brazilian rock quarry.

In other news of the ancient past, researchers studying Oetzi, a 5,300-year-old body discovered frozen in the Italian Alps, have found red blood cells around his wounds, representing the oldest red blood cells ever observed.

A study of people from the Solomon Islands in Melanesia suggests that they evolved their striking blonde hair independently of people in Europe. This refutes the possibility that blonde hair was introduced by colonial Europeans, says Carlos Bustamante, a Stanford University geneticist.

A collection of ochre-tinted human bones in the Oxford University Museum of Natural History, known as the Red Lady of Paviland, is older than previously thought, according to a new analysis. At 33,000 years old, the bones represent one of the earliest examples of ceremonial burial in Western Europe.

In a southern Illinois coal mine, the largest fossil forest ever discovered may shed new light on climate change today.

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ESA Heads to Jupiter

The European Space Agency has set its sights on Jupiter and its icy moons. A probe, called Juice, was approved at a meeting of member state delegations in Paris. It would be built in time for a launch in 2022.

In other space news, when Hal Levison presented what he called a "slightly radical" mechanism for building the solar system's giant planets, he received a pastry in the face for his trouble. Luckily, he was wearing a catcher's mask.

Astronomers have observed a star in another galaxy plunging toward a giant black hole and being ripped to shreds, sparking a flare so brilliant that observers detected it from a distance of 2.1 billion light-years.

Meanwhile, here on Earth, in the week since a fireball shot across the sky and exploded, scattering a rare type of meteorite over California's Gold Country, the hills have drawn a new rush of treasure seekers.

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Greenland Ice Loss 30 Percent Faster Than a Decade Ago

Greenland's glaciers are melting at an increasing rate, though not at the breakneck pace that scientists once feared, a new study has found.

In other environmental news, researchers have found in long-term studies that some plants are flowering up to eight times faster than computer models anticipate.

Genetically modified crops in the Midwest and South are having unanticipated consequences, including "Trojan corn," "super weeds" and the disappearance of monarch butterflies.

More water moved into and out of the atmosphere in 2000 than in 1950, making parts of the world's oceans saltier and fresher waters less salty, researchers report.

Pacific reef shark populations have declined by 90 percent or more over the past several decades, according to a new study, and much of this decline stems from human fishing pressure. It seems that shark populations fare worse the closer they are to people--even if the nearest population is an atoll with fewer than 100 residents.

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Star Truck: The Age of Private Space Missions Is About to Dawn

from the Economist

SPACE flight defies mere reason. From its beginning in the 1950s until the present day, it has teetered along the line that divides science from science fiction. The rocketeers who took America into orbit were, many of them, space cadets drawn to the field by the shiny spaceships and bug-eyed monsters of the pulp fiction of their boyhoods--and the same was probably true of their Soviet counterparts. What they produced, too, was only quasi-real. The Apollo programme, to land a man on the Moon and return him safely to Earth, in the words of John Kennedy, America's president at the time, was a deadly serious engineering and diplomatic project. It aimed to show the world that American know-how was better than the Russian variety. But it was also an idealised fantasy of American power. ("We came in peace, for all mankind.") The flag Neil Armstrong planted in the Sea of Tranquility staked a claim to what many hoped would be a new frontier.

In the case of Apollo, reality--in the form of government budget cuts--triumphed over the plans for a permanent moon base. But 40 years later the tension between fantasy and reality in space remains, as two new projects show.

The first, announced in April, seems closer to the dreamy end of the spectrum. A group of rich Americans, among them James Cameron, a film director with a penchant for science fiction, announced that they planned to boldly go into the void to mine asteroids for precious metals. This modern version of a good, old-fashioned gold rush could be a classic sci-fi tale, with the accent on the fi: it will probably cost a fortune (some think $2.5 billion just to drag a 500-tonne asteroid to the Moon), and, even if the investors' plans really do come true, the platinum, iridium and other precious metals would arrive in such quantity that they would rapidly become a lot less precious.

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The Climate Fixers

from the New Yorker (Registration Required)

Late in the afternoon on April 2, 1991, Mt. Pinatubo, a volcano on the Philippine island of Luzon, began to rumble with a series of the powerful steam explosions that typically precede an eruption. Pinatubo had been dormant for more than four centuries, and in the volcanological world the mountain had become little more than a footnote. The tremors continued in a steady crescendo for the next two months, until June 15th, when the mountain exploded with enough force to expel molten lava at the speed of six hundred miles an hour. The lava flooded a two-hundred-and-fifty-square-mile area, requiring the evacuation of two hundred thousand people.

Within hours, the plume of gas and ash had penetrated the stratosphere, eventually reaching an altitude of twenty-one miles. Three weeks later, an aerosol cloud had encircled the earth, and it remained for nearly two years. Twenty million metric tons of sulfur dioxide mixed with droplets of water, creating a kind of gaseous mirror, which reflected solar rays back into the sky. Throughout 1992 and 1993, the amount of sunlight that reached the surface of the earth was reduced by more than ten per cent.

The heavy industrial activity of the previous hundred years had caused the earth's climate to warm by roughly three-quarters of a degree Celsius, helping to make the twentieth century the hottest in at least a thousand years. The eruption of Mt. Pinatubo, however, reduced global temperatures by nearly that much in a single year. It also disrupted patterns of precipitation throughout the planet. It is believed to have influenced events as varied as floods along the Mississippi River in 1993 and, later that year, the drought that devastated the African Sahel. Most people considered the eruption a calamity.

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Global Warming Heats Up Tornado Debate

from NewScientist

LAST year was a particularly deadly year for tornadoes in the US, with the second highest death toll in 137 years. Already this year, major outbreaks have killed 63 people. All eyes are now on May, when the season usually peaks, amid talk in some quarters of another year of extremes.

The result is that discussion about human influences on severe thunderstorms and tornadoes has been reignited. Such discussion is not new. It seems that, following every major tornado event in the last decade, the influence of rising levels of atmospheric carbon dioxide has been questioned. Human impacts have been talked about for much longer than that, however. Three tornadoes that killed at least 90 people in 1953 led to speculation that atmospheric tests of nuclear weapons caused them.

But the speculation has been one-sided, with talk of human influences on tornadoes following disasters, but little about whether human influences have acted as a brake on their numbers after anomalously low activity.

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When Good Moods Go Decisively Bad

from Science News

Feeling peppy may lead older adults to settle for less. In a new study, seniors in a good mood compared fewer options and made worse choices than did those in a bad mood or younger participants.

"Positive emotions may have costs for older adults' decision making," says study coauthor Bettina von Helversen, a psychologist at the University of Basel in Switzerland.

A bright mood makes it harder to select a quality option from a series of choices, such as finding a bargain on a new computer offered at different prices by various online sites, say von Helversen and University of Basel colleague Rui Mata.

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