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Sunday, June 1, 2008

How to harvest solar power? Beam it down from space!

LONDON, England (CNN) -- Jyoti is the Hindi word for light. It's something Pranav Mehta has never had to live without. And he is lucky. Near where he lives in Gujarat, one of the most prosperous states in India, thousands of rural villages lack electricity or struggle with an intermittent supply at best.

art.solar.na.jpg

Massive solar satellites would beam power back to ground-based receivers on Earth.

"We need to empower these villages, and for empowerment, energy is a must," Mehta said. "Rural India is suffering a lot because of a lack of energy."

By 2030, India's Planning Commission estimates that the country will have to generate at least 700,000 megawatts of additional power to meet the demands of its expanding economy and growing population.

Much of that electricity will come from coal-fired power plants, like the $4 billion so-called ultra mega complex scheduled to be built south of Tunda Wand, a tiny village near the Gulf of Kutch, an inlet of the Arabian Sea on India's west coast. Dozens of other such projects are already or soon will be under way.

Yet Mehta has another solution for India's chronic electricity shortage, one that does not involve power plants on the ground but instead massive sun-gathering satellites in geosynchronous orbits 22,000 miles in the sky.

The satellites would electromagnetically beam gigawatts of solar energy back to ground-based receivers, where it would then be converted to electricity and transferred to power grids. And because in high Earth orbit, satellites are unaffected by the earth's shadow virtually 365 days a year, the floating power plants could provide round-the-clock clean, renewable electricity.

"This will be kind of a leap frog action instead of just crawling," said Mehta, who is the director of India operations for Space Island Group, a California-based company working to develop solar satellites. "It is a win-win situation."

American scientist Peter Glaser introduced the idea of space solar power in 1968.

NASA and the United States Department of Energy studied the concept throughout the 1970s, concluding that although the technology was feasible, the price of putting it all together and sending it to outer space was not.

"The estimated cost of all of the infrastructure to build them in space was about $1 trillion," said John Mankins, a former NASA technologist and president of the Space Power Association. "It was an unimaginable amount of money."

NASA revisited space solar power with a so-called "Fresh Look" study in the mid-90s but the research lost momentum when the space agency decided it did not want to further pursue the technology, Mankins told CNN. By around 2002 the project was indefinitely shelved -- or so it seemed.

"The conditions are ripe for something to happen on space solar power," said Charles Miller, a director of the Space Frontier Foundation, a group promoting public access to space. "The environment is perfect for a new start."

Skyrocketing oil prices, a heightened awareness of climate change and worries about natural resource depletion have recently prompted a renewed interest in beaming extraterrestrial energy back to Earth, Miller explained.

And so has a 2007 report released by the Pentagon's National Security Space Office, encouraging the U.S. government to spearhead the development of space power systems.

"A single kilometer-wide band of geosynchronous Earth orbit experiences enough solar flux in one year to nearly equal the amount of energy contained within all known recoverable conventional oil reserves on Earth today," the report said.

The study also concluded that solar energy from satellites could provide power for global U.S. military operations and deliver energy to disaster areas and developing nations.

"The country that takes the lead on space solar power will be the energy-exporting country for the entire planet for the next few hundred years," Miller said.

Russia, China, the European Union and India, according to the Pentagon report, are interested in the concept. And Japan, which has been pouring millions of dollars into space power studies for decades, is working toward testing a small-scale demonstration in the near future.

But a number of obstacles still remain before solar satellites actually get off the ground, said Jeff Keuter, president of the George C. Marshall Institute, a Washington-based research organization. "Like any activity in space, there are enormous engineering challenges," he said.

One major barrier is a lack of cheap and reliable access to space, a necessity for launching hundreds of components to build what will be miles-long platforms. Developing robotic technology to piece the structures together high above Earth will also be a challenge. Then there is the issue of finding someone to foot what will be at least a billion-dollar bill.

"It will take a great deal of effort, a great deal of thought and unfortunately a great deal of money," Keutersaid. "But it is certainly possible."

And Miller, of the Space Frontier Foundation, said he thinks it will be possible in the next 10 years.

"We could see the first operational power satellite in about the 2020 time frame if we act now," he said.

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Do you think beaming solar power down from space is feasible? Who should be responsible developing the technology? Why has it not been done before? Leave your views and comments in the Sound Off box below and we'll publish the best.

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Hacker changes Phoenix Mars Lander Web site

TUCSON, Ariz. -- A spokeswoman for the Phoenix Mars Lander mission says a hacker took over the mission's public Web site during the night and changed its lead news story.

Spokeswoman Sara Hammond says a mission update posted Friday was replaced with a hacker's signature and a link redirecting visitors to an overseas Web site.

Hammond says the site hosted by the University of Arizona has been taken off line while computer experts work to correct the problem.

The Mars Lander vehicle touched down on the Red Planet last Sunday to search for traces of organic compounds that are the basic building blocks of life.

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Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2008 June 1

A Twisted Solar Eruptive Prominence
Credit: SOHO Consortium, EIT, ESA, NASA

Explanation: Ten Earths could easily fit in the "claw" of this seemingly solar monster. The monster, though, visible on the lower left, is a huge eruptive prominence seen moving out from our Sun. The above dramatic image taken early in the year 2000 by the Sun-orbiting SOHO satellite. This large prominence, though, is significant not only for its size, but its shape. The twisted figure eight shape indicates that a complex magnetic field threads through the emerging solar particles. Differential rotation inside the Sun might help account for the surface explosion. Although large prominences and energetic Coronal Mass Ejections (CMEs) are relatively rare, they are occurred more frequently near Solar Maximum, the time of peak sunspot and solar activity in the eleven-year solar cycle.

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NASA to put Buzz Lightyear on International Space Station


NASA and Disney are teaming up to put a figurine of 'Toy Story' space ranger Buzz Lightyear on the Space Shuttle Discovery when it launches on Saturday. The toy will be taken to the International Space Station, the destination for the shuttle.

(Credit: Disney)

Talk about cross-promotion.

One of the closest things to Disney World's Orlando, Fla., home, is NASA's Kennedy Space Center, and this is relevant because on Friday, it was announced that among the objects expected to be blasted into the sky with the planned Saturday launch of the Space Shuttle Discovery is a figurine of Toy Story space ranger Buzz Lightyear.

Disney World, of course, is where the new Toy Story Mania ride has just opened.

The idea behind putting Buzz Lightyear aboard the Space Shuttle has to do with the "Toys in Space" initiative NASA and Disney are starting. This is an educational program designed to inspire children's interest in space and celestial discovery.

This is all also relevant to me because on June 10, I'll be hitting the highways for Road Trip 2008. I'll start in Orlando, and before I visit many of the South's most interesting destinations, I'll be stopping by both Disney World and the Kennedy Space Center.

At the theme park, I expect to visit and do a story on the Toy Story ride, and at the NASA facility I hope to be able to see the Space Shuttle land.

If the latter happens, however, I won't be seeing Buzz Lightyear, as the toy will have stayed behind on the space station.

Stay tuned to the Road Trip, and be sure to keep up, both now and during the trip, with what I'm doing on Twitter.

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Twittering From Mars -NASA's Tiny URL


Mars_2 Social networking has started spreading through space. The Phoenix Lander (which I suspect you may perhaps have heard of) has its very own Twitter account, and thousands are already following its far flung messages.

Twitter is status-message network, stripping down the entire web community scene to the simple message "What are you doing now?" And if anybody has a more interesting answer to that than the Phoenix they're either lying or on fire. The 140 character limit enforces sharp, interesting updates (countering the endless verbiage that plagues sites like livejournal), while allowing links to other interesting content - like, for example, brand new images of the Martian surface.

Of course the Lander itself isn't SMSing across the solar system - it's a little busy examining a planet - so somebody at NASA is writing on its behalf. The result is a fascinating news ticker combining just the right combination of amazing information, a cute helpful tone, and thoughtful responses to questions. The characterization of the probe is a nice touch, but I'm already trepidating the tearful farewell (in a few months at most when the Martian winter freezes the Phoenix). I'm sure the messages will stay chipper until last call, but if you can think of something sadder than a friend going cold and silent over a hundred million miles from home then you should probably get psychological help.

It's great to see such excellent use of the latest applications. Government institutions trying to get with it usually turn out like a Tyrannosaur trying to high-five: at best a failure, at worst a painful tragedy. NASA, however, are by definition an organization composed of rocket scientists and it turns out they're pretty on the technological ball.

So if you're horrified that so many people use a revolution in communications computing to talk about the sandwich they just had, follow @MarsPhoenix and raise your Twitter IQ. I get a huge kick out of firing up my twitterstream (@lukemckinney) in the morning and finding that my buddy flungabunga is continuing to rock Sydney, willowbl00's head has changed color again, oh and by the way WE PUT SOMETHING ON MARS AND IT'S TALKING TO THE INTERNET.

Posted by Luke McKinney.

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Music special: Five great auditory illusions

The scale illusion is an example of our brains grouping similar notes together
The scale illusion is an example of our brains grouping similar notes together

As part of our special issue on music, Daniel Levitin has written The Music Illusion, which looks at auditory illusions and how they can help us understand the workings of the human brain. Here we have compiled five of the most striking auditory illusions discovered so far.

We had a big pool to choose from, from the mysterious quintina (fifth voice) heard in some types of throat-singing, to the saxophone break that isn't on Lady Madonna (it's actually the Beatles singing into their cupped hands - not to be confused with the actual sax solo) and the soaring guitar sound of Pink Floyd's Dave Gilmour. Listen to our top 5 below, and read our explanations of the effects involved.

1 Barber's shop illusion (Listen with headphones)

This is a demonstration of the stereo effect. Listening to it, you feel as though you are in a barber's chair, with the barber moving around you, clipping away at your hair. As the barber "moves" to your right, the volume increases slightly in the right channel and decreases in the left. Similarly, increases in the volume of sound from the clippers give the impression that he is bringing them closer and closer to each ear. The illusion demonstrates our ability to locate sounds in space; by comparing the inputs to the two ears, we can work out where a sound is coming from.

2 Phantom words (Listen through stereo separated loudspeakers, best placed some distance apart)

This illusion was first demonstrated by Diana Deutsch at the University of California, San Diego. Building on the stereo effect described above, the recording features overlapping sequences of repeating words or phrases, located in different regions of stereo space. As you listen to it, you'll start to pick out specific phrases. However, none of the phrases are really there. Your brain is constructing them, in a bid to make sense of a meaningless noise. Indeed, you may find that the phrases you hear are related to what's on your mind – for example, people who are dieting often hear phrases associated with food.

3 Temporal induction of speech

Much of human perception is the result of the brain filling in gaps in the data from our senses. This means that if a part of an audio recording is missing, our brains will often work out what should have been there. In this recording by Richard Warren from the University of Wisconsin in Milwaukee, a spoken sentence is interrupted by a cough. One of the phonemes has actually been completely removed by the cough. But not only do most people hear the complete sentence, they generally find it very difficult to work out which phoneme has been deleted. If the phoneme is replaced by a period of silence, rather than a cough, the deletion is very obvious.

4 Scale illusion (Listen through stereo headphones, or stereo separated loudspeakers, best placed some distance apart)

Another effect first demonstrated by Diana Deutsch, this is an example of our brains "grouping" similar notes together. Two major scales are played: one ascending, one descending. However, the notes alternate from ear to ear – for instance, the right ear hears the first note of one scale, and then the second note of the other (see diagram, top right).

There are several ways in which people perceive these sounds, but the most common is to group the high and low notes together. Rather than hearing the two scales, people hear a descending and re-ascending melody in one ear, and an ascending and descending melody in the other. In other words, the brain reassigns some of the notes to a different ear in order to make a coherent melody. Right-handed people tend to hear the high melody in the right ear, and the low one in the left, while left-handers show a more diverse response.

5 Phantom melodies

Some pieces of music consist of high-speed arpeggios or other repeating patterns, which change only subtly. If they're played fast enough, the brain picks up on the occasional notes that change, and links them together to form a melody. The melody disappears if the piece is played slowly.

Compare these recordings of Christian Sinding's Frühlingsrauschen ("Rustle of Spring"). At the higher speed, the changing notes linger in your perception long enough to be linked into a melody, but at the lower speeds they're too widely separated. (original recording: www.classicalmidi.co.uk / Slow recording courtesy of Karle-Philip Zamor)

Frühlingsrauschen, full speed


Frühlingsrauschen, one-quarter speed

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Why Are Senior Female Scientists So Heavily Outnumbered by Men?


There is some funny math in the world of academic science.

Take my graduate school for example: My class was made up of eight people -- seven women and one man, or 7 to 1. He was Snow White and we were the seven dwarves -- each with a remarkably appropriate nickname. I was Grumpy, should you be curious to know.

Snow White and at least four of the dwarves have continued on to postdoctoral research jobs. That is a 4 to 3 ratio of women who went on to do a post-doc to those that chose alternate career paths.

Everything is adding up so far, right? Lots of women are around. Lots of science is being done. All is well.

The next set of numbers is slightly puzzling, however. That is the ratio of female to male professors in our department, at a well-respected academic institution, is 48 to 7 men to women.

Interesting reversal, isn’t it? We go from 7 to 1 in grad school to roughly 1 to 7 in professorships.

Clearly, something does not compute. Where did all the women go? What is happening to all the women en route from graduate school to professorship? Where is the leak? Then again, is it a leak, or more like a pressurized stream? What is applying this pressure to force women out of a career in science? Is it societal pressure to be a mom and take care of the family? Have generations of both men and women perpetuated the belief that in a fist fight between family and work, one or the other has to crawl away a loser? Do some women lack self confidence and convince themselves that they don’t have what it takes to succeed in academic science?

It is perfectly acceptable, even commendable if women make the choice, which is rightfully theirs, to stay at home, to choose careers outside of science, or to choose, well, anything at all.

It would be all right if the scientific community is still paying catch up with the rest of society in accepting women into their midst and the ratio will equalize in the next decade (not sure there is evidence either for or against this, but I feel compelled to present it nonetheless).

It is not acceptable if women are forced to choose between a family and a career in science.

It is not acceptable if women are feeling unwelcome in the male-dominated, and occasionally inhospitable, scientific community.

It is not acceptable if their being female is detrimental to their careers.

So what is the solution? Let women make their own decisions whether to stay or to go. Remove as many obstacles and pressures as possible and let the choice be theirs. Isn’t that the whole point of the much-maligned term, feminism? Institute reasonable day care at universities. Allow for extended maternity leave and the option of paternity leave. Don’t cut women any breaks. They are no less inherently able to achieve than men, regardless of what certain Nobel Prize winners and heads of major Universities may say. They don’t need pity or hand me downs. They just need the freedom to choose.

Anna Kushnir, PhD

Anna Kushnir recently earned a doctoral degree from a top academic institution. She is also the creative force behind Lab Life, an excellent blog on the Nature Network.

Update: These statements are reflective of her experiences and opinions, but they are backed by exhaustive studies: The proportion of female faculty in her department, 14 percent, is exactly equal to the overall average from the top fifty US chemistry departments.

Wired Science is quite interested in covering other issues at the intersection of science and culture. Feel free to send us your letters.

Photo: Akash K / flickr

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Caring or cruel? Inside the primate laboratory

The Guardian, given rare access to an animal research facility, talks to scientists about their experiments on monkeys

Marmoset monkeys used in experiments are often subjected to precision brain surgery. Photograph: Graeme Robertson

Anna stares at the computer screen and considers her options. In front of her are two shapes - a flower and a stripy diamond. If she picks the right one she will be rewarded with banana milkshake, but the wrong choice will briefly switch the lights off in her Perspex box. She opts for the diamond and is plunged into darkness.

During the next nine minutes Anna makes the same mistake over and over again. The neuroscientists who designed this experiment are testing how good Anna is at learning new rules. Over the last few weeks she has learned that the diamond was her ticket to a tasty, sugary drink, but this is the first test in which the rules have been reversed. Most of the subjects adapt quickly. But Anna is different.

In March she was subjected to precision brain surgery in which researchers destroyed a small area of her brain. To the untrained eye this has not affected her behaviour at all; she moves, eats and socialises normally. But the experiments are showing that the specific brain region knocked out is crucial for subtle behavioural abilities.

If Anna was human, this experiment would not be possible. But the studies conducted on her and the other marmosets at one of the most controversial research facilities in the UK are providing vital insights into the brain malfunctions that cause psychiatric conditions such as schizophrenia, obsessive compulsive disorder (OCD), attention deficit hyperactivity disorder (ADHD) and depression.

Animal rights campaigners condemn this research as cruel and unnecessary. This week, the renowned primatologist Dr Jane Goodall urged the EU to do more to promote other routes to cures. She advocated a Nobel Prize for alternatives to animal testing. She said: "We should admit that the infliction of suffering on beings who are capable of feeling is ethically problematic and that the amazing human brain should set to work to find new ways of testing and experimenting that will not involve the use of live, sentient beings."

The European commission is reviewing Directive 86/609, which governs animal research across the EU. Goodall and groups who oppose animal experimentation hope to pressure the commission to include a timetable for ending primate testing altogether.

"Primate use is deeply embedded into the system and the prospect of ending it brings significant resistance from some researchers, who have been known to make overblown and unscientific statements about the 'critical necessity' of their research," said a spokesperson for the British Union for the Abolition of Vivisection (BUAV).

The Guardian was granted access to the controversial facility. We were allowed to visit every room in the complex and see every animal on the understanding that we did not reveal its location. The names of workers at the site have been changed to protect their identities.

Despite being a world-class neuroscientist, Jessica, who runs the secret marmoset research facility at a leading UK university, rarely talks openly about her job. "I very seldom tell anyone what I actually do, because you just don't know who you are talking to," she said. Police have found her name on a hit list compiled by animal rights extremists and she is afraid that if her involvement becomes more widely known her home and family might be targeted.

To minimise the chance of her identity being revealed, Jessica has never before talked to a journalist. But now she feels a duty to speak. "I'm fed up with the amount of misinformation that's constantly put out," she said.

She particularly objects to the photographs on anti-vivisection websites depicting monkeys terrified because protesters have broken in during the night or images that are deliberately cropped to make the cages look tiny. They are often decades out of date, she said. "The disorders which we are trying to treat are crippling to people. I would love it if we could just tell the world what we do."

Her anonymous building with mirrored windows looks no different from any other set of academic offices. Inside there is the familiar faint university whiff of the academic coffee room, but here it is mingled with the pungent smell of monkey urine. The marmosets are housed in nine rooms, in cages nearly 3 metres (9ft) high that are full of ladders, beams and ropes. The cages are bespoke, designed specifically with the needs of this species in mind. The monkeys, which are bred on site, live either in family groups of up to 15 or in pairsm, as they would in the wild.

"What we try to do is, as closely as possible, give them all the opportunities they would have in the wild," said Peter, the lab's animal welfare officer. The facility has been visited by marmoset specialists at UK zoos who wanted to learn from the state-of-the-art husbandry that Peter has developed. "I think a lot of people have the idea that you have mad scientists with primates in cages stuck on their desks. That's just not what it is," he said.

In the marmoset kitchen, Peter prepares the monkeys' daily menu. Their basic diet consists of egg and Complan sandwiches, along with pellets that give them the correct balance of minerals. But Peter also includes a dried fruit and nut mix, fresh apples, bananas, pears, grapes and peanuts. Farley's rusks, Heinz banana delight, malt loaf and the marmosets' favourite - mini marshmallows - are also in the larder.

Groups who oppose the use of animals in research claim that scientists force their monkeys to perform by starving them and withholding water. Peter vigorously denied this. Even without the treats they receive during the experiments, he said the animals receive a nutritionally balanced diet. Breeding animals receive exactly the same diet as the experimental monkeys.

"It is restricted. We restrict the times when they have treats. But we are not starving the animals by any stretch of the imagination and we are not dehydrating the animals," he said. Apart from Peter's desire to treat the animals well and his obligation to do so under the strict husbandry regulations stipulated by the Home Office, he said treating the animals badly would be counter-productive, because animals forced into participating in experiments would give unreliable results.

Every monkey has a numbered collar, but each one also has a name. The colony's family tree goes back to 1978 and each year the researchers choose a theme for the names so that it is easy to tell when a monkey was born. Gin and Tonic, for example are two marmosets from 2005, the drink-themed year. Hermione was born in 2003 - the Harry Potter year. This year's dual theme is herbs and cars. "This may sound strange, but I work here because I love animals. It's as simple as that," Peter said.

For those who oppose primate research though, even the best welfare conditions entail suffering. "We know that the heightened sentience, intelligence and emotional needs of monkeys make even day-to-day life in a laboratory cage a grave animal welfare issue - quite aside from the horrifying suffering that can be caused by invasive brain studies or protracted poisoning tests," said the BUAV spokesperson.

And this is the crunch point for many people uneasy about experimenting on the brains of creatures so close in evolutionary terms to ourselves.

To investigate how the monkeys' brains work the researchers must destroy parts of the brain tissue. That involves shaving the marmoset's head, drilling tiny holes into its skull, inserting a needle and injecting a tiny quantity of toxin. To destroy some brain structures, the scientists must make up to eight brain lesions. All of this happens in an operating theatre on site using equipment and anaesthetic the same as would be used in human brain surgery.

The operations, under anaesthetic, last around three hours. Typically, the marmosets take around four hours to come round, at which point they are reunited with their cage mate. They are monitored as they recover from the anaesthetic and a vet is on call for all the monkeys day and night.

One of the post-doctoral researchers introduces a pair of experimental animals, Anna and Hedwig, that underwent brain surgery in March and April respectively. The fur on Hedwig's head is still growing back, but he is bounding around the cage like all the others. "You are a mallow monster - yes," said Sarah in a high-pitched baby voice as she hands a marshmallow through the bars of the cage. She knows 20 animals by sight and said they have unique personalities.

It is Anna's turn for her behavioural test. "I would honestly say that they like testing. If, for some reason, you don't test one for a day they are not happy with you," said Sarah. She places a small Perspex box next to an opening in the cage and Anna jumps in immediately to grab the marshmallow on offer. Sarah takes her to the experimental room where Anna spends a few minutes pressing on the computer screen. Despite failing to receive the milkshake, Anna shows no sign of being stressed by the exercise and she is back in her cage with Hedwig within 10 minutes.

The research in the lab is not aimed at testing the effectiveness of specific new drugs against the simian equivalents of human brain diseases or testing how toxic new products are. They are aimed at understanding the basic neural architecture of primates (including us) so that treatments for brain diseases even become a possibility. One focus is on testing the monkeys' behavioural flexibility and finding out which areas of the brain are responsible. It is these parts of the brain that are altered in conditions such as OCD and ADHD.

OCD patients feel compelled to repeat behaviours such as washing their hands. Anna, returning time and again to the wrong symbol in her computer test, is performing the equivalent behaviour, said Jessica. When OCD patients are given the same rule-changing task they act in the same way. The difference with Anna is that it is possible to work out which part of the brain is responsible for the behaviour and so offer options for treating the symptoms in people.

Jessica is adamant that the insights her team is providing into how the human brain works would simply not be possible any other way. "I really don't believe there is an alternative at the moment," she said. "Tissue cultures don't behave. Imaging can't get at cause and effect. Modelling can't work unless you understand what you are trying to model." No scientist would choose to work on animals unless there was no alternative, she said. It is expensive, bureaucratic and dangerous because of the lengths to which some who oppose the work are prepared to go. "You need to do something for this huge number of people who suffer from these really debilitating psychiatric disorders. We can't do that unless we understand how the brain controls our behaviour."

Critics say using animals in research is simply old-fashioned science. "Urgent action is needed to improve the protection of animals and to replace unethical and outdated animal experiments with non-animal techniques," said Dr Gill Langley of the Dr Hadwen Trust, a non-animal medical research charity. She favours methods such as tissue culture, computer modelling and brain scans, which she says are more advanced and relevant to human patients.

Backstory

Research using non-human primates is the most controversial area of animal research, but it accounts for a tiny minority of experiments. No great apes (chimpanzees, orangutans and gorillas) have been used in experiments in the UK since 1986 and it has been government policy not to use them since 1997. No prosimians (for example, bush babies and lemurs) have been used for several years. Baboons have not been used since 1998. Scientists argue that animal research is highly regulated to ensure it is carried out as humanely as possible. Home office inspectors make unannounced visits to licensed laboratories to check standards of animal welfare. A five-year licence can take six months of detailed work to put together and submit to the Home Office. The research is expensive. Housing a marmoset for a year costs around £4,000; a larger macaque monkey around £18,000.

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RANDOM ACTS OF EVOLUTION

The idea of humankind as a paragon of design is called into question by the puffer fish genome - the smallest, tidiest vertebrate genome of all.

The genome of the PUFFER FISH offers a point of comparison by which we can measure the efficiency and efficacy of our own. Illustration by Alison Schroeer.

When I mention the Japanese puffer fish, or fugu, to friends and students who are even slightly pop-culture savvy, I get a predictable response: That's the fish that almost killed Homer Simpson! The fugu is an actual fish, and a beautiful little advanced bony one. Among its claims to fame is that it protects itself from being eaten by secreting a potent neurotoxin called tetrodotoxin that blocks nerve impulses and can kill a person in a high enough dose. That's part of the reason humans eat it, though: If carefully prepared and not eaten in excess, it can provide a peculiar tingle to the lips—and the thrill of a little danger. In the well-known episode of The Simpsons, Homer discovers the joys of sushi, overindulges in poorly prepared fugu, thinks he has only a day to live, and typical sitcom hijinks ensue (ruined slightly for us science geeks, who know that fugu poisoning leads to rapid paralysis, which would tend to interfere with hijinks).

Fugu has another property of greater interest to evolutionary and developmental biologists, molecular biologists, and geneticists, though: It has an unusual genome. Through genomes, biology organizes genetic material into different forms of life; what we often find is that the real surprises are deep, hidden, and require a delicate sense of appreciation. In order to explain what's unusual about the fugu's genome, a comparison with our own human genome is in order.

One of the clear results of the Human Genome Project is that our genomes are incredibly junky: Our DNA contains approximately 3.2 billion base pairs, about the amount of information that can be stored on a single CD, but only about 5 percent of that information plays a significant role in constructing the human form. Our human CD contains, in effect, the equivalent of one really good, but short, pop song, with the rest of the tracks being staticky hisses, noise, and repetitions of the same short phrase, over and over again.

Now, you might want to argue that we simply lack the sophistication to appreciate the other 95 percent. But we actually do know what the function of a significant fraction of the junk is, and that it's not to our benefit.

One element common to both human and fugu is a DNA sequence called LINE, short for Long Interspersed Element. LINE, itself a gene about 6,000 base pairs long, codes for an enzyme called a reverse transcriptase. The key here is that it recognizes its own RNA sequence, and repeatedly inserts copies of itself into our genome. LINEs seem to be relics of the "copying machinery" of old viral infections wherein a virus would embed a portion of itself into our genome, not enough to propagate the full, infectious virus, but enough to continue copying itself. It is a classic example of a selfish gene: It has no purpose but to do only that, without benefit to us.

Another repeated element in the genome is a shorter sequence called a SINE, or Short Interspersed Element. These are only a few hundred base pairs long and don't actually do anything, as they don't code for a functional protein. They do contain regulatory elements that trigger the cellular machinery to make RNA from them, however, and this SINE RNA has a selfishly advantageous property: It is recognized by the LINE reverse transcriptase, which can obligingly insert duplicate SINEs back into the genome.

There are overwhelming numbers of these repeated elements in the human genome: about a half-million copies of LINEs and about a million copies of SINEs, taking up about 45 percent of the total DNA. Note also that most of these copies are actually broken, since the few functioning copies of the LINE enzyme aren't particularly efficient and often insert only fractional copies. In addition, we have about 20,000 genes taking up 5 percent of the genome that do all the essential work of the organism—making liver enzymes and hemoglobin and the keratin of our skin and regulating the patterns of gene expression and so forth—so you can easily get the impression that the primary purpose of human cells is to maintain a cozy environment for the proliferation of junk DNA. This is more than mere junk, though: The perfect word for it is kipple, the term coined by science fiction author P.K. Dick for unwanted junk that tends to reproduce itself and grow.

It is disconcerting for us to discover that our cells aren't well-honed, efficient machines dedicated to making just the important stuff of us, but rather are carting around massive quantities of useless bric-a-brac and debris. Which brings us back to the fugu. Its genome is a tiny 365 million bases, one-eighth the size of the human genome, and the fugu genes take up a full third of that sequence (rather than 5 percent), while the repetitive DNA has been reduced to a sixth of the total (rather than 45 percent). Yet fugu aren't missing anything, and are as sophisticated and complex on the cellular, tissue, and organismal level as other vertebrates. What's the source of the difference?

While the molecular evidence suggests that fugu aren't immune to LINEs and SINEs and that they are infected with more diverse reverse transcriptases than we are, fugu have evolved mechanisms for dealing with these selfish segments of DNA that go beyond merely silencing them. They also actively excise them from the genome. This probably was not the result of an abrupt process. It may simply be that the repetitive elements are deleted at a slightly higher rate than that at which they can add themselves to the genome, leading to a gradual paring away of the junk. In the world of genomic housekeeping, the puffer fish is a neatnik who keeps the trash under control, while the rest of us are pack rats hoarding junk DNA.

There's a lot of thought these days going into trying to figure out some adaptive reason for such a sorry state of affairs. None of it is particularly convincing. We'd be better off reconciling ourselves to the notion that much of evolution is random, and that nothing prevents nonfunctional complexity from simply accumulating. As evolutionary biologist T. Ryan Gregory puts it, any functional explanation for all that junk has to take into account why an onion would need so much more of it than we do. He calls it the onion test.

Perhaps an important lesson from the differences is that efforts to use quantitative measures of complexity to justify a ladder of life, with some species held as "more evolved" than others, are an exercise in futility. Bony fish like fugu and land-dwelling tetrapods like humans diverged over 450 million years ago, and what we've both been doing is busily accumulating differences, not superiority in one lineage or another. Consider that when you're cautiously nibbling at your carefully prepared sushi. The fish you consume are as wonderful and complex as you are, and may even have surpassed you, when it comes to their genome, in their degree of elegance.

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MIT develops a 'paper towel' for oil spills

A mat of nanowires with the touch and feel of paper could be an important new tool in the cleanup of oil and other organic pollutants, MIT researchers and colleagues report in the May 30 online issue of Nature Nanotechnology.

The scientists say they have created a membrane that can absorb up to 20 times its weight in oil, and can be recycled many times for future use. The oil itself can also be recovered. Some 200,000 tons of oil have already been spilled at sea since the start of the decade.

"What we found is that we can make 'paper' from an interwoven mesh of nanowires that is able to selectively absorb hydrophobic liquids--oil-like liquids--from water," said Francesco Stellacci, an associate professor in the Department of Materials Science and Engineering and leader of the work.

In addition to its environmental applications, the nanowire paper could also impact filtering and the purification of water, said Jing Kong, an assistant professor of electrical engineering in the Department of Electrical Engineering and Computer Science and one of Stellacci's colleagues on the work. She noted that it could also be inexpensive to produce because the nanowires of which it is composed can be fabricated in larger quantities than other nanomaterials.

Stellacci explained that there are other materials that can absorb oils from water, "but their selectivity is not as high as ours." In other words, conventional materials still absorb some water, making them less efficient at capturing the contaminant.

The new material appears to be completely impervious to water. "Our material can be left in water a month or two, and when you take it out it's still dry," Stellacci said. "But at the same time, if that water contains some hydrophobic contaminants, they will get absorbed."

Made of potassium manganese oxide, the nanowires are stable at high temperatures. As a result, oil within a loaded membrane can be removed by heating above the boiling point of oil. The oil evaporates, and can be condensed back into a liquid. The membrane--and oil--can be used again.

Two key properties make the system work. First, the nanowires form a spaghetti-like mat with many tiny pores that make for good capillarity, or the ability to absorb liquids. Second, a water-repelling coating keeps water from penetrating into the membrane. Oil, however, isn't affected, and seeps into the membrane.

The membrane is created by the same general technique as its low-tech cousin, paper. "We make a suspension of nanowires, like a suspension of cellulose [the key component of paper], dry it on a non-sticking plate, and we get pretty much the same results," Stellacci said.

In a commentary accompanying the Nature Nanotechnology paper, Joerg Lahann of the University of Michigan concluded: "Stellacci and co-workers have provided an example of a nanomaterial that has been rationally designed to address a major environmental challenge."

In addition to Stellacci and Kong (who is also affiliated with MIT's Research Laboratory of Electronics, or RLE), other authors are Jikang Yuan, a postdoctoral associate in MIT's Department of Electrical Engineering and Computer Science (EECS) and RLE; Xiaogang Liu, now at the National University of Singapore; Ozge Akbulut of the Department of Materials Science and Engineering; Junqing Hu of the National Institute for Materials Science in Japan; and Steven L. Suib of the University of Connecticut, Storrs.

This work was primarily funded by the Deshpande Center for Technological Innovation at MIT.

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Machine to clean up greenhouse gas is breakthrough in war on global warming, say scientists

Scientists say they have invented a machine that can suck carbon dioxide out of the air – potentially creating a vital weapon in the war against global warming.

The blueprint for the CO2 'scrubber' raises the prospect of a generation of machines which would help reduce the billions of tonnes of greenhouse gases being pumped into the atmosphere by the use of fossil fuels.

The team of US scientists now plans to build a prototype which would capture one tonne of CO2 from the air every day.

Holy grail? How one of the CO2-scrubbing machines would look


Though the idea is considered a holy grail in the battle against climate change – and Sir Richard Branson has put up £12.6 million for anyone who makes it a reality – the machines would fall far short of a quick fix.

The prototype, being built at a laboratory in Tucson, Arizona, by a company called Global Research Technologies, will cost about £100,000 and take about two years to construct.

The devices – each nearly the size of a shipping container - would have to be produced in their millions to soak up human carbon emissions.

US physicist Klaus Lackner

Inventor: US physicist Klaus Lackner says his machine offers more hope than attempts to cut down carbon emissions

The idea is bound to be controversial, with environmentalists seeing so-called technological solutions to global warming as undermining attempts to promote greener lifestyles and industries.

But physicist Klaus Lackner, who led the U.S. team behind the invention, said the CO2 scrubber offered more hope than current efforts to cut carbon emissions by reducing fossil fuel use.

' I'd rather have a technology that allows us to use fossil fuels without destroying the planet, because people are going to use them anyway,' he said.

Scientists say it is not difficult to remove carbon dioxide from the atmosphere by absorbing it in various chemical filters. But the problem has been how to clean those filters of CO2 so they can then be reused to carry on the job.

Professor Lackner, of New York's Columbia University, says the solution lies in a newly discovered property of absorbent plastic sheets known as 'ion exchange membranes' which are routinely used to purify water.

It turns out that humid air can make these membranes 'exhale' the CO2 they have trapped – leaving them clean and ready to absorb another load.

The Lackner team says the captured carbon dioxide could then be pumped into greenhouses to boost plant growth.

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Wasted Energy

It's gone before you even knew it was there: As energy is unlocked from fuels at power plants, two-thirds of the energy consumed to create electricity is lost.

The laws of thermodynamics dictate that conversion efficiency will never be 100 percent, because heat is lost at every step of the conversion process. But new technologies may be able to greatly increase conversion efficiency, moving from an overall rate of 36 percent to closer to 50 percent.

At present, coal — in all its carbon-belching inefficiency — is king because it's cheap. Still, the use of natural gas to create electricity has been rising rapidly, in part because of more-efficient gas turbines.

Natural gas prices have been climbing, however, and coal prices could rise as well.

"High fossil fuel prices will drive technology and innovation, because they respond to price signals," said Frank A. Wolak, an economist at Stanford. "Technology can improve efficiency by working the margin, gaining 10 to 15 percent. That's money."

Adding a carbon tax or regulating carbon trading could also change price incentives, increasing demand for nuclear and renewable energy sources.

"Once the cost of burning fossil fuels doubles, the renewable energy options begin to look really good," said Jon G. McGowan, a mechanical engineer at the University of Massachusetts.

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Coca-Cola Switching to Carbon Dioxide-Based Beverage Coolers


A few years ago, Coca-Cola decided it would significantly decrease its environmental impact. When it took a good look at where its environmental footprint was highest, it saw that vending machines are a big culprit.

Let’s take a moment to accept the “Duh” of this.

To combat the vending machine factor, Coca-Cola began replacing HFC machines with CO2 machines. Yep – Carbon Dioxide is helping our environment! By the end of 2006, the company had 6,000 units placed world-wide (yes, that’s relatively few when considering they have 10 million machines operating around the globe, but still nothing to sneeze at). Continuing with that trend, they’ve drastically increased their CO2 machine intake by purchasing 100,000 new compressed carbon dioxide beverage coolers.

The new machines will emit 75% fewer greenhouse gasses, though they cost about 25% more. This is significant when considering that HFCs are major global warming pollutants and, if allowed to run as rampant as they currently are, their overall contribution to global warming pollution could nearly double within 40 years. Compressed Carbon Dioxide-based cooling units, on the other hand, will help reduce the impact of these HFC clunkers on our planet – and since Coca-Cola is a global company, it truly is a global issue.

On top of purchasing the new CO2 machines, Coca-Cola has also invested $40 million to research next generation refrigeration technologies. Lets hope this research includes looking into that little factor of electricity consumption required by those 10 million machines to light up, take your money, and spit out a cold beverage.

If you think like me, you have a LOT of questions buzzing about the true bonuses of this project, like what is happening to the old machines; and are they really replacing old HFC machines, or just adding to the number of machines in their fleet while still running those pesky HFC coolers for however long they’ll keep chugging away; and what is the environmental impact of producing the CO2 machines in the first place; and on and on. Well, I guess if you think like me, then we’ll all just have to take a deep breath and go one step at a time. Step one: Congratulate Coca-Cola on taking a significant lead on reducing emissions via clean(er) technology.

Via cleantech, coca-cola, goodcleantech, r744

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