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The joys of parenthood: Father’s day
Thu, 17 May 2012 15:05:40 GMT
WILL fatherhood make me happy? That is a question many men have found themselves asking, and the scientific evidence is equivocal. A lot of studies have linked parenthood—particularly fatherhood—with lower levels of marital satisfaction and higher rates of depression than are found among non-parents.Biologically speaking, that looks odd. Natural selection might be expected to favour the progeny of men who enjoy bringing them up. On the other hand, the countervailing pressure to have other children, by other women, may leave the man who is already encumbered by a set of offspring dissatisfied.To investigate the matter further Sonja Lyubomirsky, a psychologist at the University of California, Riverside, decided both to study the existing literature, and to conduct some experiments of her own. The results, just published in Psychological Science, suggest parenthood in general, and fatherhood in particular, really are blessings, even though the parent in question might sometimes feel they are in disguise.Dr Lyubomirsky’s first port of call was the World Values Survey. This is a project which...
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Bionics (I): A mind to walk again
Thu, 17 May 2012 15:05:40 GMT
ANYONE who saw Claire Lomas complete this year’s London marathon on May 7th cannot fail to have been impressed by her grit and determination. Ms Lomas, once a show jumper, was paralysed from the chest down by a riding accident in 2007, so finishing a marathon, albeit at walking pace, was a dramatic feat. Some of the adulation, however, should be reserved for the technology that helped her do so: a pair of bionic legs.Ms Lomas’s legs were designed by Amit Goffer, an Israeli engineer who is himself paralysed. They have various modes (“sit”, “stand” and “walk”, and “ascend” and “descend” for staircases) and are controlled by a keypad worn on the wrist. Walking also requires the assistance of a pair of crutches. But Dr Goffer’s legs allowed Ms Lomas to travel the 42.195km (26 miles and 385 yards) of the marathon course in stages, over a period of 16 days.That record may not last long, however. Another engineer, José Contreras-Vidal of the University of Houston, in Texas, has what may prove an even better design: a pair of bionic legs that respond directly to signals from the brain. (An early version is...
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Bionics (II): I think I’d like some coffee
Thu, 17 May 2012 15:05:40 GMT
HELPING yourself to a cup of coffee may seem like a small, everyday thing. But not if you are quadriplegic. Unlike paraplegics, for whom the robotic legs described in the previous article are being developed, quadriplegics have lost the use of all four limbs. Yet thanks to a project organised by John Donoghue of Brown University, in Rhode Island, and his colleagues, they too have hope. One of the participants in his experiments, a 58-year-old woman who is unable to use any of her limbs, can now pick up a bottle containing coffee and bring it close enough to her mouth to drink from it using a straw. She does so using a thought-controlled robotic arm fixed to a nearby stand. It is the first time she has managed something like that since she suffered a stroke, nearly 15 years ago.Arms are more complicated pieces of machinery than legs, so controlling them via electrodes attached to the skin of someone’s scalp is not yet possible. Instead, brain activity has to be recorded directly. And that is what Dr Donoghue is doing. Both his female participant and a second individual, a man of 66 also paralysed by a stroke, have...
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Geoengineering: Implicit promises
Wed, 16 May 2012 19:47:42 GMT
FOR the past few years, a European collaboration called IMPLICC (Implications and Risks of Novel Options to Limit Climate Change) has been looking at what it might mean to engineer the climate, by reducing the amount of sunshine that reaches the Earth’s surface. A lot of IMPLICC’s work, like much else in climate science, has taken the form of computer modelling. In its case the models try to mimic the effects of things like putting veils of reflective particles into the stratosphere, or brightening the clouds over the oceans.This week the IMPLICC team and other interested parties met in Mainz, Germany, to discuss the results—for the various models have turned out to agree far better than many of their creators expected. In particular, they suggest that particles in the stratosphere can indeed stop rising levels of greenhouse gases raising the overall global temperature, though in doing so they slightly cool the tropics while the poles warm a bit. Other things being equal, the models also agree that geoengineering tends to suppress the hydrologic cycle, with less evaporation and less rainfall.Some researchers, however, want to go beyond modelling. They wish to experiment in the real world. The highest-profile of these schemes has been part of a programme called SPICE (Stratospheric Particle Injection for Climate Engineering), which is paid for mainly by Britain’s Engineering...
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Modern alchemy: Turning a line
Thu, 10 May 2012 15:06:15 GMT
ONE of the first inklings that chemistry has an underlying pattern was the discovery, early in the 19th century, of lithium, sodium and potassium—known collectively as the alkali metals. Though different from each other they have strangely similar properties. This was one of the observations that led a German chemist called Johann Döbereiner to wonder if all chemical elements came in families.It took decades to tease out the truth of Döbereiner’s conjecture, and thus to construct the periodic table—in which the alkali metals form the first column. And it took decades more to explain why the table works (it is to do with the way electrons organise themselves in orbit around atomic nuclei). But it is a fitting tribute to Döbereiner’s insight that, if all goes well, some time in the next few months will bring the creation of a new alkali metal, element number 119, by his countryman Christoph Düllmann of the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt. With that addition the table will do something which has never happened before. It will grow a new row.Come in number 119An element’s...
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Carbon capture and storage: A shiny new pipe dream
Thu, 10 May 2012 15:06:15 GMT
AS Helene Boksle, one of Norway’s favourite singers, hit the high notes at the Mongstad oil refinery on May 7th, the wall behind her slid open. It revealed, to the prime minister and other dignitaries present, an enormous tangle of shiny metal pipes. These are part of the world’s largest and newest experimental facility for capturing carbon dioxide.Such capture is the first part of a three-stage process known as carbon capture and storage (CCS) that many people hope will help deal with the problem of man-made climate change. The other two are piping the captured gas towards a place underground where the rocks will trap it, and then actually trapping it there. If the world is to continue burning fossil fuels while avoiding the consequences, then it will need a lot of CCS. There is no other good way to keep the CO2 emitted by power stations, and also by processes such as iron- and cement-making, out of the atmosphere. To stop global warming of more than 2°C—a widely agreed safe limit—carbon-dioxide emissions must be halved by 2050. According to the International Energy Agency, an intergovernmental body that...
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Optoelectronics: Graphene shows its colours
Thu, 10 May 2012 15:06:15 GMT
GRAPHENE, a form of carbon that comes in sheets a single atom thick, has gained a reputation as a wonder material. It is the best conductor yet discovered of heat at room temperature and is 40 times stronger than steel. It is also a semiconductor whose electrical conductivity is 1,000 times better than silicon’s. This means it could be used to make devices far more sensitive than is possible now, leading some to predict that it will one day become the material of choice for computer chips. There was little surprise, therefore, when Andre Geim (pictured above) and Konstantin Novoselov, two physicists who were investigating graphene’s structure, won the 2010 Nobel prize for their work.Actually converting the wonders of graphene into products has been tough. But Frank Koppens and his colleagues at the Institute of Photonic Sciences in Barcelona think they have found a way to do so. As they describe in Nature Nanotechnology, they believe graphene can be used to make ultra-sensitive, low-cost photodetectors.Photodetectors are devices which convert light into electricity. They are used in...
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Salt-tolerant rice: Nuclear-powered crops
Thu, 03 May 2012 15:00:45 GMT
Irradiated food
THOSE who turn their noses up at “genetically modified” food seldom seem to consider that all crops are genetically modified. The difference between a wild plant and one that serves some human end is a lot of selective breeding—the picking and combining over the years of mutations that result in bigger seeds, tastier fruit or whatever else is required.Nor, these days, are those mutations there by accident. They are, rather, deliberately induced, usually by exposing seeds to radiation. And that is exactly what Tomoko Abe and her colleagues at the Riken Nishina Centre for Accelerator-Based Science in Saitama, outside Tokyo, are doing with rice. The difference is that Dr Abe is not using namby-pamby X-rays and gamma rays to mutate her crop, as is the way in most other countries. Instead she is sticking them in a particle accelerator and bombarding them with heavy ions—large atoms that have been stripped down to their nuclei by the removal of their electrons. This produces between ten and 100 times as many mutations as the traditional method, and thus increases the chances...
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Counting animals: Written in blood
Thu, 03 May 2012 15:00:45 GMT
Feed me!
ONE difficulty faced by conservationists is getting hold of reliable statistics on the animals they are looking after. For good reason many species, particularly herbivores with a lot of predators, are rather shy. In tropical forests the problem is especially acute, since the dense jungle is perfect for hiding in. That makes it hard to know how well a given species is really doing.In a paper just published in Current Biology, though, a group of researchers led by Ida Baerholm Schnell, of Copenhagen Zoo, describe a clever, low-cost solution. Their idea is to take another well-known difficulty of doing fieldwork in tropical forests—the endless swarms of bloodsucking leeches—and turn it into a scientific tool.Leeches can go for months without food, surviving on blood stored from their last victim. Tipped off by a previous paper, which reported that viruses can survive inside blood sucked up by leeches for as long as half a year, Dr Schnell and her colleagues wondered if DNA from a leech’s most recent victim might be recoverable as well.To find out,...
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Private space flight: Keep on truckin’
Thu, 03 May 2012 15:00:45 GMT
SIX years ago, when NASA, America’s space agency, announced it wanted the private sector to take over responsibility for ferrying cargo to the International Space Station (ISS), many scoffed that it was a fantasy. But yesterday’s fantasy has become today’s reality, and private enterprise is busy putting together rocket-propelled delivery vans to do just that—and, eventually, to take astronauts as well. One of the leading firms in the field, SpaceX, has already notched up a string of successful flights (and a few failures, too) with its Falcon rockets, pictured above. This month it will attempt its most ambitious mission yet: a rendezvous with the space station.If all goes according to plan, a Falcon 9 rocket carrying an unmanned Dragon space capsule will blast off from Cape Canaveral in Florida. After three days in orbit, the Dragon will put itself on a trajectory that will bring it close to the station, starting an intricate orbital dance that will allow SpaceX and the astronauts aboard the station to test the capsule’s communications and manoeuvring systems. If...
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Flu research: How to make bird flu fly, part one
Wed, 02 May 2012 18:17:28 GMT
ON APRIL 27th, after much toing and froing, the Dutch government gave Ron Fouchier of the Erasmus Medical Centre in Rotterdam permission to submit his paper on bird flu to Science. Dr Fouchier is the head of one of two groups studying how bird flu might become transmissible between people. In December the authorities in America and the Netherlands prevented both his group and the other, led by Yoshihiro Kawaoka of the University of Wisconsin-Madison, from publishing their findings, lest they get into the wrong hands. This official fear stemmed from the deadly nature of bird flu. Of the 602 human cases reported since 2003, 355 have been fatal. The factor that has stopped the death toll being worse is that people have to catch the virus directly from a bird (usually a chicken). It rarely, if ever, passes from one person to another.Science has yet to publish Dr Fouchier’s manuscript, but its rival Nature has gone ahead and published Dr Kawaoka’s. This paper got clearance from the American authorities on April 20th. So it is now possible to...
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Scientific freedom and security: Jail-bird flu
Thu, 26 April 2012 15:02:43 GMT
Dangerous thoughts?
RON FOUCHIER (pictured), of the Erasmus Medical Centre in Rotterdam, is the lead author of a controversial paper which lays out how deadly H5N1 avian influenza, or bird flu, can be made deadlier still. He believes this information should be widely disseminated, so that biologists can work on drugs or vaccines to combat the new strain—which Dr Fouchier and his team created by combining five flu mutations that are currently (and separately) circulating in the wild.Others, however, disagree. The authorities in the Netherlands are pondering stopping the paper’s publication because of fears its findings could be misused by hostile governments or terrorists. That pondering has been going on since December, and Dr Fouchier is growing restless. A decision is expected soon, but he recently went as far as saying that he would disregard it, if it went against him, and would publish regardless. He has now softened his stance, but defiance could see him in prison.The contentious paper looks at how the new form of influenza passes between ferrets. Since, as flu goes, ferrets are...
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Genomic research: Consent 2.0
Thu, 26 April 2012 15:02:43 GMT
Sign here
IN AN age where people promiscuously post personal data on the web and regularly click “I agree” to reams of legalese they have never read, news of yet another electronic consent form might seem like a big yawn. But for the future of genomics-related research the Portable Legal Consent, to be announced shortly by Sage Bionetworks, a non-profit research organisation based in Seattle, is anything but mundane. Indeed, by reversing the normal way consent to use personal data is acquired from patients in clinical trials, it could spell a new relationship between scientists and the human subjects of their research, with potential benefits that extend well beyond genomics.Share and enjoyThe heart of Portable Legal Consent is the notion that anyone who signs up for a clinical trial, or simply has his genome read in order to anticipate the risk of disease, should easily be able to share his genomic and health data not just with that research group or company, but with all scientists who are prepared in turn to accept some sensible rules about how they may use the data...
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Mining asteroids: Going platinum
Thu, 26 April 2012 15:02:43 GMT
CAN reality trump art? That was the question hovering over the launch on April 24th, at the Museum of Flight in Seattle, of a plan by a firm called Planetary Resources to mine metals from asteroids and bring them back to Earth.It sounds like the plot of a film by James Cameron—and, appropriately, Mr Cameron is indeed one of the company’s backers. The team behind the firm, however, claim they are not joking. The company’s founders are Peter Diamandis, instigator of the X Prize, awarded in 2004 to Paul Allen and Burt Rutan for the first private space flight, and Eric Anderson, another of whose companies, Space Adventures, has already shot seven tourists into orbit. Larry Page and Eric Schmidt, respectively the chief executive and the chairman of Google, are also involved. So, too, is Charles Symonyi, the engineer who oversaw the creation of Microsoft’s Office software (and who has been into space twice courtesy of Mr Anderson’s firm). With a cast-list like that, it is at least polite to take them seriously.As pies in the sky go, some asteroids do look pretty tasty. A lot are unconsolidated piles of rubble left over...
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The history of science: A fishy tale
Thu, 19 April 2012 15:09:45 GMT
This engraving, of a flying fish, almost changed the course of history. It is one of a set from John Ray’s and Francis Willughby’s book “Historia Piscium”, published in 1686 by the Royal Society and recently put online by them for the edification of scholars everywhere. The society, which today proudly describes itself as the world’s oldest scientific academy (it was founded in 1660), was almost bankrupted by the expense of the high-quality illustrations in what was regarded at the time as a leading natural-history text, but which unfortunately failed to sell as well as its publishers had hoped. As a result, no money was left over for another publication, “Principia Mathematica”, by Isaac Newton. That the most important volume in the history of physics, which described the laws of motion and of gravity, saw the light of day the next year was, in the end, due to the deep pockets of Edmund Halley, of comet fame. Halley was the son of a wealthy soapmaker and he stumped up much of the cost himself.
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Sexual strategies: I just called…
Thu, 19 April 2012 15:09:45 GMT
WHEN Stevie Wonder crooned “I just called to say ‘I love you’,” he was bang on when it comes to men and women in their sexual prime. Were the ballad sung by a post-menopausal matron, though, the person at the other end of the line would probably be her daughter—and the conversation would revolve around grandchildren. That, at least, is the picture which emerges from a study published in Scientific Reports by Robin Dunbar, of Oxford University, and his colleagues.Evolutionary psychologists like Dr Dunbar are interested in how investment in close relationships differs between the sexes. Dr Dunbar, indeed, has just published a book on the phenomenon of sexual love, analysed from a scientific point of view (see article). These differences reflect distinct strategies that have evolved to maximise reproductive success across a lifetime. One prediction that makes intuitive sense, but which has been difficult to nail down empirically, is that when women hit the reproductive wall of the menopause they funnel their remaining energy into bolstering their children’s—especially their daughters’—odds of producing viable offspring. (Sons spend less time minding their progeny than their spouses do.)The main obstacle to testing the grandmother hypothesis, as it has come to be known, is...
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The science of civil war: What makes heroic strife
Thu, 19 April 2012 15:09:44 GMT
FOR the past decade or so, generals commanding the world’s most advanced armies have been able to rely on accurate forecasts of the outcomes of conventional battles. Given data on weather and terrain, and the combatants’ numbers, weaponry, positions, training and level of morale, computer programs such as the Tactical Numerical Deterministic Model, designed by the Dupuy Institute in Washington, DC, can predict who will win, how quickly and with how many casualties.Guerrilla warfare, however, is harder to model than open battle of this sort, and the civil insurrection that often precedes it is harder still. Which, from the generals’ point of view, is a pity, because such conflict is the dominant form of strife these days. The reason for the difficulty is that the fuel of popular uprisings is not hardware, but social factors of a type that computer programmers find it difficult to capture in their algorithms. Analysing the emotional temperature of postings on Facebook and Twitter, or the telephone traffic between groups of villages, is always going to be a harder task than analysing physics-based data like a tank’s...
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Exercise and addiction: Fun run
Thu, 12 April 2012 15:07:08 GMT
You expect me to what?!
AS THE legions of gym bunnies and jogging enthusiasts who race out into the spring sunshine every year clearly demonstrate, running can be fun. More specifically, running triggers the release of brain chemicals called endocannabinoids that create a potent feeling of pleasure. As their name suggests, these endocannabinoids work in the same way as the active ingredient of marijuana.From an evolutionary standpoint this surge of endocannabinoids, and the “runner’s high” it creates, make sense. For ancient humans, remaining fit enough to run after game and away from predators and enemies was vital for survival. Yet whether other mammals are also driven to exercise by endocannabinoids has remained a mystery. Now a study led by David Raichlen of the University of Arizona has revealed that the runner’s high does exist in other species, but not in all.Dr Raichlen hypothesised that endocannabinoid-driven exercise highs would be found in those mammals that gain an evolutionary benefit from being fast on their feet: antelopes, horses and wolves, for example. However, he also...
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Photoelectric cells: To dye for
Thu, 12 April 2012 15:07:08 GMT
THE phrase “indoor solar power” sounds like an oxymoron. But there is growing interest in the idea of using photoelectric cells to run gadgets as well as power grids—and doing so even when those gadgets are inside buildings. Much of the light these cells used would, of necessity, come from incandescent bulbs, fluorescent tubes and light-emitting diodes (LEDs) rather than through the window from the sun. But if the right sorts of cells were available this could be cheaper than constantly replacing the batteries that currently power electronic gizmos.On April 8th G24 Innovations, a firm based in Wales, announced that it may have come up with just such a cell. The latest version of its special, dye-based photoelectric devices has set a new record for the conversion of light from bulbs into electricity: an efficiency of 26%, compared with the 15% which previous ones can manage. That lifts dye-based cells to the point where they might be widely deployable for indoor power.Dye-based cells are similar to the silicon-based variety found on rooftops around the world in that both rely on a semiconductor to assist the conversion of luminous energy into the electrical sort. The difference is that in the case of silicon cells, this conversion happens directly. That means the frequency of light absorbed is constrained by the physical properties of silicon itself.In the case of dye-based...
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Dental X-rays: Little and not often, please
Thu, 12 April 2012 15:07:08 GMT
Less is more
IF YOU are a suspicious type you may be disturbed by the fact that, despite reassurances of the safety of the procedure, dentists and their technicians, when administering X-rays, usually step out of the room while the deed is done. Not only that, they often drape a lead-lined apron over your body to protect your vital organs. Well, all but one: your brain.A study by Elizabeth Claus, of Yale University, just published in Cancer, suggests your suspicions might be justified. Dr Claus thinks she has identified, in those who have had dental X-rays often, a significant rise in the admittedly small risk of developing a brain tumour.In rich countries, five men in every 200,000, and twice as many women, develop tumours called meningiomas that affect the membranes surrounding the brain. Meningiomas account for a third of primary brain tumours. Only about 2% of them are malignant, but non-malignant does not mean non-dangerous. Even a “benign” meningioma can kill. Around 30% do so within five years of diagnosis. Symptoms can include seizures and blindness, and...
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