In the largest study of its kind, researchers have found that exposure to cigarette smoke can alter gene expression -- the process by which a gene's information is converted into the structures and functions of a cell. These alterations in response to smoking appear to have a wide-ranging negative influence on the immune system, and a strong involvement in processes related to cancer, cell death and metabolism. Source: ScienceDaily: Latest Science News | 14 Jul 2010 | 9:00 am
New research suggests that athletes and footballers may want to limit the time they spend training at altitude to improve their performance. A new study has found that people with a rare condition that mimics being at high altitude for long periods show metabolic differences that actually reduce their endurance and physical performance. Source: ScienceDaily: Latest Science News | 14 Jul 2010 | 9:00 am
In any battle, sizing up one's opponent is a critical first step. For researchers fighting a bacterial infection, that means assessing every nook and cranny of the malicious microorganism and identifying which to attack. In Spain, scientists are devising maneuvers they hope will take out bacteria at their molecular knees, and they are optimistic a recent advance will yield therapies for a number of infections, including antibiotic-resistant strains delivering blow after blow across the globe. Source: ScienceDaily: Latest Science News | 14 Jul 2010 | 9:00 am
"Living fossil" cycads now number about 300 species, and many of these species are endangered, especially those on islands like Guam. New molecular research on a threatened species, Cycas micronesica, shows these plants are not relics and that there is hope in careful management of the remaining plants. Source: ScienceDaily: Latest Science News | 14 Jul 2010 | 9:00 am
Gorillas hit-and-run in 'games' of tag in the same way humans do and for the same reason -- to keep their competitive advantage, a new study has found. It is the first study to show apes, like humans, will hit a playmate then run in order to try to get away with the upper hand. Source: ScienceDaily: Latest Science News | 14 Jul 2010 | 9:00 am
The intensity of cravings for cigarettes has more to do with the psychosocial element of smoking than with the physiological effects of nicotine as an addictive chemical, according to a new study by an Israeli scientist. He hopes this research will help clinicians and health authorities develop more successful smoking cessation programs than those utilizing expensive nicotine patches or gum. Source: ScienceDaily: Latest Science News | 14 Jul 2010 | 9:00 am
A landmark study is the first to identify a life-or-death "cell competition" process in mammalian tissue that suppresses cancer by causing cancerous cells to kill themselves. Central to the discovery was the researchers' identification of "Mahjong" -- a gene that can determine the winners of the competition through its close relationship with another powerful protein player. Source: ScienceDaily: Latest Science News | 14 Jul 2010 | 6:00 am
Scientists studying ancient species migration believe northern birds had the ability to colonize continents that southern species lacked. The research reveals how the ancient 'land bridge' of Panama, which first connected North and South America, caused an uneven species migration, leading to a new understanding of species diversity today. Source: ScienceDaily: Latest Science News | 14 Jul 2010 | 6:00 am
NASA's Juno spacecraft will be forging ahead into a treacherous environment at Jupiter with more radiation than any other place NASA has ever sent a spacecraft, except the sun. In a specially filtered cleanroom in Denver, where Juno is being assembled, engineers recently added a unique protective shield around its sensitive electronics. Source: ScienceDaily: Latest Science News | 14 Jul 2010 | 6:00 am
Detecting oral cancer in its earliest stages can save the lives of the nearly 40,500 people diagnosed annually. But early detection has been difficult. Researchers discovered a biomarker, called human beta defensin-3, which may serve as an early warning. The defensin is present in all oral cancers and associated with the early stages of oral cancer. Source: ScienceDaily: Latest Science News | 14 Jul 2010 | 6:00 am
AFP - Russian companies are ready to supply fuel to energy-hungry Iran, despite unilateral US and EU sanctions targeting Tehran's oil and gas sectors, the Russian energy minister said on Wednesday.
AP - The plan to start choking off oil gushing into the Gulf of Mexico was suddenly halted as government officials and BP said further analysis must be done Wednesday before critical tests could proceed.
Physicists have moved to quash rumours that the elusive Higgs boson has been detected by a US "atom smasher". Source: BBC News - Science & Environment | 14 Jul 2010 | 2:14 am
Whether or not science can explain everything is a question that was never far from the minds of a large group of theologians and scientists who met in Oxford last week. They'd assembled to celebrate the 80th birthday of John Polkinghorne, the professor of mathematical physics who made his name for his work on quarks, now an Anglican priest, and author of many books on science and religion. Moreover, it turns out that the question of science's limitations is intimately linked to Polkinghorne's much misunderstood account of God's action in the world.
The challenge is to avoid concocting a "God of the gaps" – a deity whose action occurs in the gaps where scientific explanations apparently fall short. The best known example of this is probably the bacterial flagellum. Advocates of intelligent design have argued that these whip-like devices for locomotion can only be explained by divine intervention because of their supposed "irreducible complexity". The trouble is that science progresses. What can't be explained in one decade is often explained in the next. Gaps get filled, and so God gets squeezed out.
Polkinghorne has been accused of advocating a God-of-the-gaps approach too. He has been taken to argue that chaos theory offers a way of understanding divine action, by virtue of the mistaken assumption that chaos theory paints a picture of an indeterminate world: if it's impossible to forecast the weather next week with any degree of accuracy, then perhaps that points to a pervasive randomness in the physical world, which God might exploit to divine advantage.
But that's not his idea, as Nick Saunders pointed out at the conference. As Polkinghorne knows better than most, the equations of chaos theory do, in fact, yield tightly causal results. The issue at stake in chaos theory is rather that you need to know the initial conditions of any system to an astonishingly high degree of accuracy to make accurate predictions. In practice, that's impossible to achieve. In other words, chaotic systems are not indeterminate, but underdetermined.
Part of the problem is that the phrase "chaos theory" is misleading. The theory is neither about chaos, nor is it a theory. Rather, it refers to a collection of mathematical equations that describe bounded systems which exhibit non-linear behaviour. Such systems are plentiful in theoretical mathematics, but are rare in nature. For example, fractals – one part of chaos theory – only approximately describe phenomena like the shape of ferns or frost crystals, because whereas the patterns in fractals repeat on any scale ad infinitum, the patterns in ferns and frost crystals don't. Fractals are only approximations of the natural world.
And it is this underdetermination that interests Polkinghorne. It means that a substantial degree of reductionism is required to use mathematics to describe the vast majority of natural phenomena – and where you have reductionism you also tend to have a limitation. As Polkinghorne puts it, science has not demonstrated that the universe is "causally closed". Instead, scientific descriptions are patchy because, in truth, we live in what the philosopher of science, Nancy Cartwright, refers to as a "dappled world". Hence, scientists have to apply different descriptions to address different levels of organisation. And often those descriptions are incompatible. (The obvious example from physics is the incompatibility of general relativity, which describes the large scale, with quantum theory, which describes the small scale.)
It's for similar reasons that scientists discuss what is known as "emergence". For example, you might know all there is to know about the behaviour of small collections of atoms in a gaseous state, but that would tell you nothing about their large-scale behaviour as a liquid or solid. That's because the large scale environment affects the behaviour of the atoms on the small scale. They are apparently subject to "top-down" causation, as much as "bottom-up" – which is to say that the phase transitions from solid, to liquid, to gas are emergent.
It's with that recognition that there is a possibility of giving an account of divine action within nature, which is compatible with science. It relies neither upon a God who intervenes outside the usual play of nature, nor seeks low-level causal gaps. Rather, God's action could be viewed as analogous to top-down, emergent causation – particularly when it implies signs of purpose or intentionality.
An obvious – though obviously contentious example – could be the relationship between mind and the neural components of the brain. To put it simply, if neurons affect our consciousness from the bottom-up, mind might be said to do so from the top-down. That'd be one way of understanding human agency. Divine agency could be described by analogical extension.
Whether or not you buy that will depend much on your prior metaphysical assumptions. We all have them. But be they theistic or otherwise, there is a general conclusion that can be posited about science: from the point of view of mathematical description, what chaos theory and reductionism more broadly demonstrate is that most of nature is scientifically underdetermined – which is to say that scientific explanations are limited. Further, it's not an epistemological gap that's being appealed to in John Polkinghorne's work, but rather an ontological causal openness. Hence the possibility, at least, of making the link with divine action.
In the second of our series on human nature, primate expert Frans de Waal disputes the conventional wisdom that overcrowded humans become more aggressive
AFP - BP was poised Wednesday to carry out a make-or-break test on the integrity of the leaking Gulf of Mexico oil well after the procedure was ordered delayed by US authorities.
In 1972, Apollo 17 brought samples of lunar soil back to Earth for analysis. Among other findings, there were "graphite whiskers." Could these tiny structures underpin some of the biggest cosmic mysteries? Source: Discovery News - Top Stories | 14 Jul 2010 | 1:11 am
Reuters - Parts of Manila may be without power until Friday after Typhoon Conson hit the Philippines' main island of Luzon, killing at least 11 people with more than 50 missing, and moved toward southern China. Source: Yahoo! News: Science News | 14 Jul 2010 | 1:07 am
How To Look Good Naked | Living With Brucie | Dragons' Den | Richard Hammond's Blast Lab | Fly Girls | John Sergeant On Tracks of Empire
How To Look Good Naked 8pm, Channel 4
Gok makes the difficult shift from GBF to man's best friend as he lines up a series of chaps with self-esteem problems and attempts to bedazzle their self-worth. First up is Simon, a handsome young man, whose body image is still bound up in the severe spine curvature he had as a teenager. Despite corrective surgery, he can't stand his own reflection. I'm yet to figure out the relationship between public nudity and empowerment – but other than that, Gok works his usual magic. JR
Living with Brucie, 9pm, Channel 4
When Wilnelia Merced brought home a twice-divorced British entertainer and told her parents she was marrying him, they were surprised – he was older than they were, as were his jokes. Still, nearly 30 years on, the marriage of Bruce Forsyth and the former Miss World he knows as Winnie is going strong, and this Cutting Edge film opens the doors on it for the first time. No DVDs were available, but it's interesting to note that someone as vigilant about his career as Brucie should want to give away very much about his private life – especially when you think of similar films made by Louis Theroux. JR
Dragons' Den 9pm, BBC2
In case you hadn't noticed, the economy hasn't been looking so good and the government is about to embark on a swingeing austerity programme. Not to worry, apparently the private sector will save us all from our folly. Doing their bit, the Dragons return to feast upon any opportunities that might still be out there. Tonight, a vineyard owner, an inventor who's been thinking about road signs and a purveyor of frozen puddings pitch for a stash of cash. JW
Richard Hammond's Blast Lab 5.15pm, CBBC
Richard Hammond has become a hero for the under-12s – thanks to a vaguely educational science show, which has proved a massive hit. Hammond runs an underground laboratory, where two teams of kids compete to win things. The losers see their toys blown up in an atmospherically controlled bidet, which is surely sending out the wrong message about consumer durability. Along the way we meet Mini Miss – Hammond's old science teacher transplanted into the body of a 10-year-old – and the lab rats: dense student volunteers who get abused by everyone. It's very funny. WH
Fly Girls 8pm, VIVA
It's a huge disappointment that this isn't about lady rappers, as the name cruelly teases, but flight attendants, and their, yawn, glamorous lifestyles. The whole thing has been shot like a spoof of a cheesy advert and its only merit lies in spotting the bits that made it legally permissible to call it a "reality" show. Oh, and watching these most tedious of characters say lines like, "When you're on a fire truck with Richard Branson, that is the coveted position at this event," with a straight face. Bizarre. RN
John Sergeant On Tracks of Empire 9pm, BBC4
John Sergeant makes for a good correspondent in India, embarking on a 3,000-mile journey across the country via its great "network of steel", the railway. Sergeant, of course, is perfectly suited for such an assignment: respectful, unruffled, if quietly passionate, one can easily imagine him as some enlightened journalist or benign diplomat overseeing the dying days of the Raj. "If you understand the railways, you can begin to understand India," he states. As they defined India's past, will they also define its future? AC
Richard Rudd, left paralysed following traffic accident, blinked three times to tell doctors he did not want to die
A man who was left paralysed and seemingly unable to communicate following a traffic accident was saved from having his life support machine turned off when he managed to blink three times to tell doctors that he did not want to die.
Richard Rudd's family had been agonising about turning off life support, his father said, after his son had said he would not want to live in a paralysed state.
But his son's remarkable response raises questions about when life should end and about how and when a family can decide if their loved one has suffered enough.
The story began in October last year, when 43-year-old Rudd, a father of two, was seriously injured after a collision led him to be thrown 20 feet from his motorbike.
The battle to save him led him to be treated at the Neurocritical care unit at Addenbrooke's hospital in Cambridgeshire.
His father, also called Richard Rudd, had given permission for doctors to withdraw treatment after his son failed to respond. "We said that knowing Richard, there was no way in a million years that he would want to live with his injuries, but doctors wanted to wait a little bit longer," he told the BBC in a programme about his son's case.
"[The doctor] held open his eyelids and asked him to move his eyes if he could hear and he moved his eyes around, so we knew he wasn't brain dead."
Intensive-care specialist Professor David Menon, 53, set up the unit 13 years ago and was in charge of Rudd's care.
He said: "He had severe injuries to his brain and we could not communicate with him. The outcome was thought to be very bleak indeed.
In fact, Richard was in a locked in state where people have relatively normal cognitive processes in the brain but are only able to allow you to know about that by movement of the eyes or eyelids.
"When, after a period of waiting, he showed voluntary movement of his eyes, everything changed. We could use these eye movements to document yes or no responses, and allow Richard to have a say in his own care."
Rudd's father added: "We're still not certain how much Richard understands … At times, it's like looking through frosted glass. But his speech therapist asked a series of questions to test him and it's definitely still Richard in there.
"He's in such a dire state that we wonder why he's smiling, but he seems to respond to the right cues.Making a living will could be detrimental to your own health.
"There must have been a time when Richard could hear what was going on but wasn't able to do anything about it.
"For my part, I'm glad he's alive and didn't make a living will."
AP - Scientists say a rare species of dark purple jellyfish is showing up in San Diego Bay and washing ashore on beaches. Source: Yahoo! News: Science News | 13 Jul 2010 | 11:16 pm
Boeing unveils an unmanned hydrogen-powered spy plane, the Phantom Eye, which is capable of flying non-stop for four days. Source: BBC News - Science & Environment | 13 Jul 2010 | 10:26 pm
Peter Greste joins a scientist researching the many different kinds of butterfly in one of the most isolated patches of tropical mountain forest in East Africa. Source: BBC News - Science & Environment | 13 Jul 2010 | 10:26 pm
An international team of scientists has begun exploring one of the most isolated patches of tropical mountain forest in East Africa. Source: BBC News - Science & Environment | 13 Jul 2010 | 10:25 pm
Great apes play tag in similar way to humans, an international team of scientists finds. Source: BBC News - Science & Environment | 13 Jul 2010 | 10:00 pm
LiveScience.com - As if almost by magic, hearing a word can make the invisible
visible, scientists now find. Source: Yahoo! News: Science News | 13 Jul 2010 | 9:30 pm
BP delays a key test on a well cap designed to stop the flow of oil into the Gulf of Mexico, after officials call for more analysis. Source: BBC News - Science & Environment | 13 Jul 2010 | 9:03 pm
WASHINGTON (Reuters) - U.S. researchers have created a primitive artificial lung that rats used to breathe for several hours and said on Tuesday it may be a step in the development of new organs grown from a patient's own cells.
A coalition of conservation organisations in England warns of the dangers of cutting public funding in the countryside. Source: BBC News - Science & Environment | 13 Jul 2010 | 8:14 pm
AP - The odds that Joan Ginther would hit four Texas Lottery jackpots for a combined nearly $21 million are astronomical. Mathematicians say the chances are as slim as 1 in 18 septillion — that's 18 and 24 zeros.
SPACE.com - ADELPHI,
Md. - NASA on Tuesday announced three new multimillion-dollar contests to build
smart robots and launch tiny satellites as part of a program to develop innovations
of benefit not only to the U.S. space agency but to the nation at large. Source: Yahoo! News: Science News | 13 Jul 2010 | 7:15 pm
A game similar to tag may prepare gorillas for real conflicts over food and mates, say researchers
Gorillas may hone their social skills and fighting tactics by playing tag, according to researchers who filmed the great apes at play in zoos across Europe.
They found that individuals often carried out "hit-and-run" strikes on other members of the group, taking a swing at them before running away. The playful attacks usually gave rise to a lumbering chase around the gorilla enclosure, with the chaser becoming the chased once they had landed their own retaliatory blow.
Footage shows them chasing and clobbering each other while displaying the open-mouthed expression of apes at play.
The gorillas' behaviour has strong similarities to the children's game tag, but is perhaps more like a playful exchange of punches that must be well-judged to ensure it does not escalate into a more serious fight.
The researchers found that the gorillas only gave chase if they were struck with a sufficiently heavy blow. Lighter strikes were ignored. "Not only did the gorillas in our study hit their playmates and then run away – chased by their playmates – they also switched their roles when hit, so the chaser became the chased and vice versa," said Davila Ross.
The game is thought to prepare gorillas for conflicts that might arise over food or mates. "This kind of playful behaviour lets them test their group members and learn what the borders are," she added. "How far you can go with an individual is important for social interactions later in life."
The study, published in the Biology Letters journal, suggests humans are not the only apes to have a sense of injustice and be motivated to seek revenge.
Gorillas and other African great apes play tag, which suggests that this common childhood game has deep primate roots. Source: Discovery News - Top Stories | 13 Jul 2010 | 5:00 pm
PROVIDENCE, Rhode Island — Rumors of the great jumping frogs of Calaveras County have not been greatly exaggerated.
The longest jump reported in scientific papers for an American bullfrog is almost 4.3 feet, says Henry Astley of Brown University in Providence, Rhode Island. Yet, new measurements have added almost three feet to that record by using California’s Calaveras County Fair as a testing ground for determining maximal species performance. Inspired by a Mark Twain story from 1865, the fair has for 83 years featured a highly competitive jumping-frog contest.
To find out how far frogs can leap in a single bound, researchers had to measure for themselves, because the contest is based on the total distance covered in three jumps.
Contest officials don’t permit scientists to set up equipment in the jumping arena, Astley says. Preserving optimal jump conditions, comparable year-to-year, is a big deal in Calaveras County. Contestants raise intense disputes over matters such as whether a fairgoer heading toward a popcorn stand has distracted a frog at a critical second.
Astley and his colleagues measured jump distance using computer analysis of video from a camera carefully positioned in the viewing area. More than half the 3,449 frog jumps researchers recorded in the 2009 contest beat the record from the scientific literature, Astley reported July 10 at the 2010 Joint Meeting of Ichthyologists and Herpetologists.
Judges at the 2009 contest declared the winning three-jump distance to be 21 feet even, as measured from the starting plate to the point where the frog finally plopped. The Brown team, however, recorded a different frog as covering the most ground on a single jump, a leap of 7.2 feet.
Such great leaps raise issues of biomechanics, Astley said. Calaveras frogs appear to be jumping farther than possible for the calculated power of bullfrog muscles. Astley speculated that the frogs amplify their power by using their leg tendons as a spring, stretching the tendons and letting them snap back all at once.
Most frog jockeys, as human contestants are known, compete using the American bullfrog (Rana catesbeiana), a large, voracious species that has invaded the West Coast from the eastern United States. Jockeys can touch their frogs only at the beginning of the first jump. Afterward, they rely on shouting, blowing or crouching behind the frog and doing their own startling leaps to urge the frogs on.
Anyone can rent a frog at the fair to enter the contest. But many serious competitors bring their own, inspiring rumors about secret locations in the wild for catching a top jumper.
Jockey expertise in locating a top frog and inspiring it matters to performance, according to Astley’s data. Jump lengths of rental frogs showed a roughly bell-shaped distribution. In contrast, non-rental frogs showed a distribution lopsided toward the high end of jump length.
By now the Calaveras frogs may indeed be reaching the outer limits of what bulllfrog species can do, Astley said. Winning jumps tended to lengthen during early decades of the contest but haven’t improved a lot since the 1980s.
“Were the pro frogs tested for steroids?” herpetologist Matt Hinderliter of The Nature Conservancy in Camp Shelby, Mississippi, asked Astley at the meeting.
No, but a frog-doping scandal would hardly explain all the study results, such as how so many of the rental frogs beat the old “maximum” distance for a jump, Astley said. Analyses of the spread of jump distances recorded at the fair, he said, suggest that scientists need to test hundreds of animals to see anything close to a species’ real maximum performance. And judging by the antics of hard-core frog jockeys, the animal’s motivation matters too.
The new energy storage concept involves a super-pressurized material that is nearly as energy-dense as explosives. Source: Livescience.com | 13 Jul 2010 | 2:26 pm
The president’s new bioethics commission examined the future of synthetic biology, including possible benefits from innovation as well as biosecurity or biosafety risks. Source: Livescience.com | 13 Jul 2010 | 1:39 pm
Jury convicts campaigner protesting against animal testing lab of attacking Oxford University with homemade petrol bombs
An animal rights activist was jailed for 10 years after being found guilty today of planting homemade petrol bombs at Oxford University.
Mel Broughton, 49, put the devices under a portable cabin at Templeton College and on the roof of a cricket pavilion at Queen's College.
The pavilion device caused damage put at £14,000, but two other bombs failed to go off. Broughton, who spearheaded animal welfare group Speak, was protesting against the building of an animal testing laboratory at Oxford.
Judge Patrick Eccles QC sentenced Broughton, of Northampton, to 10 years in jail after the jury found him guilty of conspiracy to commit arson following a four-week retrial at Oxford crown court. Broughton was originally convicted of the offences by a jury in February 2009, and successfully appealed against his conviction in February this year.
The Court of Appeal then ordered a retrial. The two and a half years Broughton has already spent in custody will be deducted from his sentence.
Instead of detecting a person's physiological response during questioning, this method measures a person's cognitive reaction. Source: Discovery News - Top Stories | 13 Jul 2010 | 12:49 pm
A photograph shows a suicide bomber ant self-detonating, killing herself and others with toxic yellow glue. Source: Discovery News - Top Stories | 13 Jul 2010 | 12:48 pm
The identity of a mysterious disease that’s raged through European salmon farms, wasting the hearts and muscles of infected fish, has been revealed.
Genome sleuthing shows the disease is caused by a previously unknown virus. The identification doesn’t suggest an obvious cure — for now, scientists have only a name and a genome — but it’s an important first step.
“It’s a new virus. And with this information now in hand, we can make vaccines,” said Ian Lipkin, director of Columbia University’s Center for Infection and Immunity, a World Health Organization-sponsored disease detective lab.
Two years ago, Norweigan fisheries scientists approached Lipkin and asked for help in identifying the cause of Heart and Skeletal Muscle Inflammation, or HSMI, the official name for a disease first identified in 1999 on a Norweigan salmon farm.
Infected fish are physically stunted, and their muscles are so weakened that they have trouble swimming or even pumping blood. The disease is often fatal, and the original outbreak has been followed by 417 others in Norway and the United Kingdom. Every year there’s more of the disease, and it’s now been seen in wild fish, suggesting that farm escapees are infecting already-dwindling wild stocks.
Lipkin’s team — which has also identified mystery viruses killing Great Apes in the Ivory Coast, and sea lions off the U.S. West Coast — combed through genetic material sampled from infection salmon pens, looking for DNA sequences resembling what’s seen in other viruses, and inferring from those what the HSMI-causing sequence should look like. Lipkin likened the process to solving a crossword puzzle. The researchers eventually arrived at the 10-gene virus they called piscine reovirus, or PRV. The virus was described July 9 in Public Library of Science One.
Related reoviruses have been found on poultry farms and cause muscle and heart disease in chickens. “Analogies between commercial poultry production and Atlantic salmon aquaculture may be informative,” wrote the researchers. “Both poultry production and aquaculture confine animals at high density in conditions that are conducive to transmission of infectious agents.”
Citation: “Heart and Skeletal Muscle Inflammation of Farmed Salmon Is Associated with Infection with a Novel Reovirus.” By Gustavo Palacios, Marie Lovoll, Torstein Tengs, Mady Hornig, Stephen Hutchison, Jeffrey Hui, Ruth-Torill Kongtorp, Nazir Savji, Ana V. Bussetti, Alexander Solovyov, Anja B. Kristoffersen, Christopher Celone, Craig Street, Vladimir Trifonov, David L. Hirschberg, Raul Rabadan, Michael Egholm, Espen Rimstad, W. Ian Lipkin. PLoS ONE, Vol. 5 No. 7, July 9, 2010.
WASHINGTON (Reuters) - NASA needs a more coherent way of projecting and controlling costs, especially on its priciest missions, a panel of experts advised on Tuesday.
EU officials plan to give the 27 member states the freedom to grow, restrict or ban genetically modified (GM) crops. Source: BBC News - Science & Environment | 13 Jul 2010 | 9:47 am
Scientists are using an unorthodox method for dealing with Lake Tahoe's Asian clam infestation: suffocating them with mats. Source: Discovery News - Top Stories | 13 Jul 2010 | 8:10 am
The extra load will be relatively slow to grow, predictable and highly localized in its early years. Source: Discovery News - Top Stories | 13 Jul 2010 | 8:02 am
NEW YORK (Reuters Health) - Older adults who get plenty of vitamin E in their diets may have a somewhat lower risk of developing dementia than those who consume less of the nutrient, a study published Monday suggests.
A massive extinction like the one that claimed the dinosaurs has hit the Earth like clockwork every 27 million years, a new fossil analysis confirms. But the study claims to rule out one controversial explanation: a dark stellar companion called Nemesis that sends a regular rain of deadly comets toward Earth.
“The main astronomical ideas you can come up with that could cause something like this just don’t work,” said physicist Adrian Melott of the University of Kansas, a co-author of the new study.
Nemesis was first suggested in 1984 as a way to explain an alarmingly regular series of extinctions in the marine fossil record, which was discovered by paleontologists David Raup and Jack Sepkoski. In light of the suggestion in 1980 that the dinosaurs were killed by a catastrophic impact, an invisible cosmic sniper lobbing comets at the inner solar system seemed like a plausible culprit.
Two independent groups of astronomers suggested that a dim brown dwarf or red dwarf star lying between one and two light-years from the sun could throw a shower of ice and rock from the Oort Cloud every 26 million or 27 million years to wreak havoc on Earth. Because the orbit of this “death star” would be tweaked by interactions with other stars and the Milky Way, the time between one impact and the next should vary by 15 to 30 percent.
But now, Melott and co-author Richard Bambach of the National Museum of Natural History in Washington, D.C., say that’s not actually what happens. The extinctions come almost exactly every 27 million years, they say, to a confidence interval of 99 percent.
“It’s really too good, it’s too sharp and fixed,” Melott said. “It’s like a clock.”
Melott and Bambach compared two huge data sets going back 500 million years, twice as far as the 1984 study looked. One dataset, the Sepkoski database, is a continuation of the original study. The other, the Paleobiology Database, was compiled between 2000 and 2008. Both sets include many fossils that have been found and cataloged since 1984.
The researchers searched mathematically for patterns that were common to both datasets, and found that both showed an excess of organisms disappearing every 27 million years, too regularly to be caused by a shiftable star.
“It was a slam dunk on finding exactly what you would expect to find if they [Raup and Sepkoski] were right, which surprised me,” Melott said. “We have strong confirmation of this periodicity, it’s exactly the same one that those guys found in ‘84, and we have no clue what’s causing it.”
Other astronomers think Nemesis is still out there, however. Richard A. Muller of the University of California at Berkeley, one of the authors of the 1984 paper proposing the dark star and the author of a popular book called Nemesis: The Death Star, thinks Melott is “coming to too strong a conclusion.”
“I would agree with most of what he says, but I think he is overestimating the accuracy of the geologic timescale,” he said. The geological record gives only an approximate sense of when major extinctions happened. “You get them in the right order, but it’s really difficult to get an actual date,” he said. In light of that uncertainty, “I would say the Nemesis hypothesis is still alive.”
There is a way to check. Several ongoing astronomical survey telescopes, including NASA’s Wide-Field Infrared Survey Explorer, the Large Synoptic Survey Telescope and the Pan-STARRS survey, are scanning the sky with enough sensitivity to find Nemesis if it exists. If they don’t find the dark star, then it probably isn’t there.
The churning clouds of dust and gas in this colorful new Hubble image of star-forming region NGC 2467 speak to the violent, tumultuous youthfulness of the region’s stars. The hot infant stars that were brewed in the cloud are emitting fierce ultraviolet radiation, sculpting and eroding the surrounding gas and making it glow in visible wavelengths.
Most of the radiation comes from the single hot, massive star just above the center of the image. Its radiation has pushed aside so much of the gas that a new generation of stars has started forming in the denser regions around the edge. Many more young stars inhabit this region than are visible in this image, but they are hidden by gas and dust.
NGC 2467 lies in the southern constellation Puppis, the Latin name for the poop deck of a ship. It is part of a larger constellation representing the Argo, Jason’s ship in Greek mythology. NGC 2467 is thought to lie about 13,000 light-years from Earth.
The picture was created from images taken with the Advanced Camera for Surveys through three different filters, shown in blue, green and red. The data were taken in 2004.
Fred Pearce argues in his book Peoplequake that fears about population growth are overblown. Earth to Fred: they aren't
Fred Pearce keeps on saying that population growth is no longer a problem. He said it again yesterday as part of his World Population Day message.
In Fred's view, it's very simple. Fertility rates have come down sharply over the past half century. Problem solved.
Sorry, Fred, saying that population growth is no longer a problem doesn't make it so, no matter how many times you say it. Neither does wishful thinking.
While admitting that world population may increase by another 2 billion or so by midcentury, he dismisses this increment as a "time-lag" problem.
Earth to Fred: 2 billion more people is a lot of people to a world that is already struggling to feed 6.8 billion people. It's a lot of people to a biosphere that is threatened with what leading biologists refer to as the Sixth Mass Extinction. And it's a lot of people to a planet that is already threatened with the effects of climate change. And while "population momentum" (i.e., large numbers of people entering their reproductive years) may account for some of the projected increase in human numbers, much of it is being driven by the fact that fertility rates in many developing countries around the world are still well above the "replacement rate."
Yes, Fred, we must do something about consumption. Unless we in the developed world do more to curb our consumption of fossil fuels and scarce minerals, the world is headed for an ecological and humanitarian disaster. We need to lower our per capita consumption of fossil fuels and other scarce resources. A lot. But I don't see the G8 or the G20 putting their heads together right now in an effort to lower consumer spending. Really, I don't. Neither do I see anything happening with respect to climate change.
And that's why it's especially important to prevent unwanted pregnancies in the U.S. and other developed nations. Sorry, Fred, it doesn't matter that America's fertility rate is right around the "replacement rate" or that Europe's is well below it. A baby born here or elsewhere in the developed world will still consume a disproportionate share of the world's resources and contribute disproportionately to the world's environmental problems.
It's also important to prevent unwanted pregnancies in the developing world. The reasons, however, are different. It really doesn't matter whether global fertility rates have dropped sharply; they remain unsustainably high in many of the least developed areas of the world. Yes, Fred, fertility rates have come down sharply in Iran and Bangladesh, but women in Afghanistan and Somalia and other desperately poor countries are still having four, five, or six children on average. Some poor countries, like Uganda and Niger, are on track to triple their populations over the next 40 years. Africa's population will likely double by mid-century.
Looking ahead, Fred, will these countries be able to feed themselves? Will they have enough safe drinking water? Will their lands be deforested or their rivers polluted? Will their maternal mortality rates and infant mortality rates remain unacceptably high? Will they be caught in a demographic poverty trap? Will they become failed states? If you have good answers to these questions, please let me know. Because if you don't, then we need to ensure that women in these developing countries are given the information and the access to contraceptives that they need to prevent unwanted and unintended pregnancies.
Someday we will be able to declare victory. Someday every woman will have access to family-planning services and reproductive health care. Someday world population will be in decline. Someday world population levels will pose no danger to the health of the planet. But that day has not arrived. Not yet. In the meantime, your breezy dismissal of the "population problem" does an enormous disservice to the planet and every living creature that calls it home.
