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Thursday, October 16, 2008

Ever wondered what space smells like? Fried steak and hot metal say scientists

By Daily Mail Reporter

Outer space smells like fried steak, hot metal and welding a motorbike, scientists said today.

Nasa has commissioned Steven Pearce, a chemist and managing director of fragrance manufacturing company Omega Ingredients, to recreate the smell of space in a laboratory.

His research will be used to help astronauts prepare for the conditions they will encounter in space.

Steak
The smell of space: Apparently mixture of steak and hot metal

The smell of space: Apparently a mixture of steak and hot metal... Just don't take your helmet off for dinner

Mr Pearce began working for Nasa in August and hopes to have recreated the smell of space by the end of the year.

He said: 'I did some work for an art exhibition in July, which was based entirely on smell and one of the things I created was the smell of the inside of the Mir space station.

'Nasa heard about it and contacted me to see if I could help them recreate the smell of space to help their astronauts.

'We have a few clues as to what space smells like. First of all, there were interviews with astronauts that we were given, when they had been outside and then returned to the space station and were de-suiting and taking off their helmets, they all reported quite particular odours.

Astronauts reported the distinctive smells when taking off their helmets following space-walks

Astronauts reported the distinctive smells when taking off their helmets following space-walks

'For them, what comes across is a smell of fried steak, hot metal and even welding a motorbike,' one of them said.

'The suggestion to us has been that it's about creating realism for their training, so they train the astronauts in their suits by putting them in big water tanks to simulate the loss of gravity and so it's just about making sure the whole thing is a realistic training exercise.

'We have already produced the smell of fried steak, but hot metal is proving more difficult. We think it's a high energy vibration in the molecule and that's what we're trying to add to it now.'

Mr Pearce visited Moorside High School in Manchester today to discuss the project, as part of the Manchester Science Festival.

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Students solve space coffee problem

Two engineering students have invented a coffee-maker which can be used by astronauts in space. ; http://link.brightcove.com/services/link/bcpid1488655367/bctid1859046623 http://www.brightcove.com/channel.jsp?channel=1139053637

Currently astronauts have to resort to drinking instant coffee heated by microwaves.

In zero gravity, water floats in globules and adheres to any receptacle in which it is placed, posing the problem of moving the water through a coffee filter.

Also, in zero gravity, the application of heat causes water to evaporate instantly.

Franklin Chang, a former NASA astronaut, decided there must be a way to allow cosmic voyagers to enjoy a true cup of filtered coffee and took the challenge to the Technological Institute of Costa Rica.

Two students at the Institute's Electromechanical School, Daniel Rozen and Josue Solano, took on the challenge and came up with a design called the space infuser.

Mr Rozen said: "We turn on the switch. The machine will heat the water to 90 degrees centigrade, the ideal temperature for a cup of coffee.

"Once the water reaches that temperature, we direct the water which is found in the heating chamber towards where the container is found, resulting in a delicious cup of coffee."

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As Phoenix Mission Ends, Project Leaders Chart Mars Future

By Andrew Moseman


(L-R) Barry Goldstein, Peter Smith and Ed Sedivy

The Mars Phoenix Lander has been a shining success for NASA. Not only did the craft reach Mars and land successfully, it also found ice in the martian soil and saw snow in the sky. But the Phoenix is now racing against time to complete more of its groundbreaking research before the harsh martian winter brings its death, said the project's science leader, Peter Smith of the University of Arizona, at the first session of the Popular Mechanics Breakthrough Conference in New York today. "It's down to the wire," Smith said at a panel discussion with two other Phoenix project leaders, Ed Sedivy from Lockheed Martin Space Systems and Barry Goldstein of NASA's Jet Propulsion Laboratory.

The Phoenix is NASA's first lander to visit the polar regions of the planet, sitting at about 68 degrees latitude, Sedivy said. But just like the northern regions on Earth, days are getting shorter there. Just after the 90th martian day of the Phoenix's visit, Goldstein said, the sun began to dip below the horizon, and now every day since then the lander's solar arrays have been able to take in less and less energy. By the end of November, Phoenix probably won't have sufficient power to operate. "It'll get so cold that the vehicle will literally freeze to death," he said.

Smith said he hopes the last few weeks of the Phoenix's mission provide excitement like the day this summer that it sent some pictures of ice that the Lander uncovered just inches below the martian surface. "When we saw the picture, we all said, 'Holy cow!,'" Smith said. The team was also shocked when Phoenix discovered perchlorate in the soil. Many reports said that the discovery of these organic salts were a bad sign for those seeking life on Mars. But not so, Smith said. While we have no idea what life on Mars would look like, scientists assume it would look like life on Earth. In that case, both ice and perchlorate are good signs. There are micoorganisms on earth that use perchlorates as an energy supply, and the scientists had hoped to find something similar on Mars. Hopefully, Smith said, the craft will have enough time before its death to make more stunning discoveries—in a couple weeks, he said, the scientists will activate the landers' microphone and send back the first sounds of Mars.

With the Phoenix's mission now ending, it leaves many unanswered questions for future Mars missions, and for those hoping to find evidence of life is what happened to the atmosphere. The red planet once possessed a denser atmosphere that it does today, which allowed liquid water's presence on the surface. "Where did that atmosphere go, and why?" Sedivy asked. He is already working one of the next mission to Mars, MAVEN, which could start to provide the answer.

MAVEN, the Mars Atmosphere and Volatile Evolution craft, is scheduled for a 2013 launch, and would then enter orbit the next year and take readings of present-day atmospheric loss. The Phoenix's findings also leave the scientists with other questions, like how deep the martian ice goes. "Is it 10 feet? 100 feet? 1,000 feet?" Smith asked. "Who knows?" Smith also hopes someday to learn how much of the planet is hiding subterranean ice, and Goldstein said that if the SUV-sized Mars Science Laboratory actually launches next year—there have been rumors of its cancellation or delay, but NASA recently recommitted to the project's timetable—then it could potentially search the soil in Mars' equatorial region for ice.

One last thing that the Phoenix could teach future Mars missions is about the uncertainty of landing there. The Phoenix Lander suffered a strange problem at the outset, according to Goldstein, when it landed at the far end of its projected landing area rather than right in the middle. He said that NASA was able to record 200 data points per second, which allowed them to reconstruct the Lander's descent and find that there was en error in the modeling data for the martian atmosphere—as a result, Phoenix's angle of descent was off by a degree, which generated lift and nearly carried it out of its projected landing area. He said this finding could help NASA plan more accurate martian landings in the future.

Those future missions may or may not find more evidence supporting the idea that Mars holds or once held life, Smith said, but anybody hoping life is out there has to be encouraged by the Phoenix Lander's mission. Not only did the lander find ice in the soil and snow in the atmosphere, it found that the martian soil had a pH of 8 or 8.5, close to that of Earth's oceans. "It's more like an Earth environment than we ever would've guessed," Smith said.

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Computer circuit builds itself

Organic molecules organize themselves to form a bridge between electrodes.

Flexible circuitsComputer circuits made from organic molecules could be used to build lightweight, flexible displays.ASSOCIATED PRESS

A team of European physicists has developed an integrated circuit that can build itself. The work, appearing in this week's Nature1, is an important step towards its ultimate goal — a self-assembling computer.

Today's computer chips are made by etching patterns onto semiconducting wafers using a combination of light and photosensitive chemicals. But the technique is being pushed to the limit as ever more processing power is being packed onto chips, requiring engineers to etch details just a few tens of nanometres across. So scientists are hunting for alternative ways to assemble even tinier chips.

“We dump it in a beaker with a solution of the molecules, we take it out, we wash it, and it works.”

Dago de Leeuw
Philips Research Laboratories, the Netherlands

Letting them build themselves is, in many ways, the most obvious solution, says Dago de Leeuw, a researcher at Philips Research Laboratories in Eindhoven, the Netherlands. "The nicest example is DNA," he says. Our genetic code provides a set of instructions that can be used to marshal molecules into an entire person, and researchers would like to come up with a similar set of compounds able to organize each other into circuits.

That's no small task. To make a circuit that is truly self-assembling, physicists would need to get insulators, conducting electrodes and semiconductor transistors to all link to each other automatically — something that is still a long way away, says de Leeuw.

Chip 'n dip

But his team has made an important step. They took a long organic molecule with mobile electrons, called quinquethiophene, that behaves like a semiconductor and attached it to a long carbon chain with a silicon group at the end, which acts an an anchor.

“Self-assembly and nanotechnology is certainly cool, but the one thing missing is higher performance.”

Hagen Klauk
Max Planck Institute for Solid State Research, Germany

The researchers then dunked a circuit board with preprinted electrodes into a solution of their new molecules. The molecules hooked on to an insulating layer between the electrodes, forming bridges from one electrode to the next. It took billions to make the connection, but they were tightly packed enough that a current could flow across them. "The different molecules are like little bricks," says Edsger Smits, another researcher at Philips. "Frankly it worked much better than we expected."

The team used the technique to construct a simple circuit that generates a code based on an input voltage. Although the system depends on the preprinted electrodes to act as a template, the circuit is truly self-assembling, says de Leeuw: "We dump it in a beaker with a solution of the molecules, we take it out, we wash it, and it works."

The new technique is impressive but still needs improvement, says Hagen Klauk, an electrical engineer at the Max Planck Institute for Solid State Research in Stuttgart, Germany. "Self-assembly and nanotechnology is certainly cool, but the one thing missing is higher performance," he says. The mobility of electrons through the circuit, he explains, means that the transistors would make for a very slow computer.

Klauk hopes that improving the characteristics of the molecules and tweaking the technique will eventually lead to self-assembling circuits that out-perform existing technologies, which use thick films of organic molecules.

For his part, de Leeuw says the next step will be figuring out a way to develop self-assembling electrodes. In the meantime, however, he says the group's circuits may already have a use. Because the bridge of molecules is very thin, it is extraordinarily sensitive to passing particles. The team believes that it could be used to develop sensors for different kinds of airborne material, such as pathogens or dangerous chemicals.

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Colossal black holes common in early universe

Artists conception of the 4C60.07 system of colliding galaxies. The galaxy on the left has turned most of its gas into stars and the black hole in its center is ejecting charged particles in the two immense jets shown. The galaxy on the right also ha ...
Artist's conception of the 4C60.07 system of colliding galaxies. The galaxy on the left has turned most of its gas into stars, and the black hole in its center is ejecting charged particles in the two immense jets shown. The galaxy on the right also has a black hole causing the galaxy's central region to shine, but much of its light is hidden by surrounding gas and dust. Vast numbers of stars are forming out of the gas and dust, and some of the material is being pulled away from the galaxy. Credit: David A. Hardy/UK ATC

Astronomers think that many - perhaps all - galaxies in the universe contain massive black holes at their centers. New observations with the Submillimeter Array now suggest that such colossal black holes were common even 12 billion years ago, when the universe was only 1.7 billion years old and galaxies were just beginning to form. The new conclusion comes from the discovery of two distant galaxies, both with black holes at their heart, which are involved in a spectacular collision.
4C60.07, the first of the galaxies to be discovered, came to astronomers' attention because of its bright radio emission. This radio signal is one telltale sign of a quasar - a rapidly spinning black hole that is feeding on its home galaxy.

When 4C60.07 was first studied, astronomers thought that hydrogen gas surrounding the black hole was undergoing a burst of star formation, forming stars at a remarkable rate - the equivalent of 5,000 suns every year. This vigorous activity was revealed by the infrared glow from smoky debris left over when the largest stars rapidly died.

The latest research, exploiting the keen vision of the Submillimeter Array of eight radio antennas located in Hawaii, revealed a surprise. 4C60.07 is not forming stars after all. Indeed, its stars appear to be relatively old and quiescent. Instead, prodigious star formation is taking place in a previously unseen companion galaxy, rich in gas and deeply enshrouded in dust, which also has a colossal black hole at its center.

"This new image reveals two galaxies where we only expected to find one," said Rob Ivison (UK Astronomy Technology Centre), lead author of the study that will be published in the Monthly Notices of the Royal Astronomical Society. "Remarkably, both galaxies contain supermassive black holes at their centers, each capable of powering a billion, billion, billion light bulbs. The implications are wide-reaching: you can't help wondering how many other colossal black holes may be lurking unseen in the distant universe."
Due to the finite speed of light, we see the two galaxies as they existed in the distant past, less than 2 billion years after the Big Bang. The new image from the Submillimeter Array captures the moment when 4C60.07 ripped a stream of material from its neighboring galaxy, as shown in the accompanying artist's conception. By now the galaxies have merged to create a football-shaped elliptical galaxy. Their black holes are likely to have merged and formed a single, more massive black hole.

The galaxies themselves show surprising differences. One is a dead system that has formed all of its stars already and used up its gaseous fuel. The second galaxy is still alive and well, holding plenty of dust and gas that can form new stars.

"These two galaxies are fraternal twins. Both are about the size of the Milky Way, but each one is unique," said Steve Willner of the Harvard-Smithsonian Center for Astrophysics, a co-author of the paper.

"The superb resolution of the Submillimeter Array was key to our discovery," he added.

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Brain structure provides key to unraveling function of bizarre dinosaur crests

A life reconstruction of the helmet-crested lambeosaur Corythosaurus. Credit: Courtesy of Michael Skrepnick.
A life reconstruction of the helmet-crested lambeosaur Corythosaurus. Credit: Courtesy of Michael Skrepnick.

Scientists at the University of Toronto, Ohio University and Montana State University now have used CT-scanning to look inside these mysterious crests and reconstruct the brains and nasal cavities of four different lambeosaur species. At the annual meeting of the Society for Vertebrate Paleontology in Cleveland, Ohio, on Oct. 16, the team will present new study findings that suggest the crests were used for communication.

"The shape of the brain can tell us a lot about what senses were important in a dinosaur's everyday life, and give insight into the function of the crests," said study lead author David Evans, a paleontologist at the Royal Ontario Museum and the University of Toronto.

Some paleontologists have suggested that the crests heightened the sense of smell by increasing the surface area of the sensory tissue. Others have argued that they regulated temperature, and still others have speculated that the crests acted as sound resonators for communication.

"It's difficult to infer the function of structures in an extinct dinosaur when there is so little resemblance to any living animal," said Jack Horner, a member of the team and paleontologist at Montana State University.

By analyzing CT scans, conducted by Lawrence Witmer and Ryan Ridgely of Ohio University's College of Osteopathic Medicine, the scientists were able to circumvent the problems of fossilization.

"Even though the soft tissues are not preserved in the fossils, the shape of the bones that encase the brain and nasal passages are," said Evans. "From there, the anatomy of these missing soft parts is easily interpreted."

The CT scan results revealed a mismatch between the external shape of the crest (which no doubt functioned as a visual display) and the internal shape of the nasal passages in closely related species, suggesting a special function for the nasal cavity. The portion of the brain responsible for the sense of smell was relatively small and primitive, indicating that the crest did not evolve to improve that sense.

Computer models done by other researchers suggest that the crests could have been used to make low, eerie bellowing calls that could have been used in communication, perhaps to call for mates or warn others of predators. The CT scans documented a delicate inner ear that confirms that the dinosaurs could hear the low-frequency calls produced by the crest.

"We were surprised to see just how large the centers of the brain associated with higher cognitive functions were," said Witmer, Chang Professor of Paleontology in Ohio University's College of Osteopathic Medicine. "We suspected that the crested duck-billed dinosaurs used both vocal and visual displays, but now we see that they had the brain power and hearing to pull off these behaviors."

When all the available information is put together, including the digital brain and ear casts, the evolutionary relationships of the species, and the growth pattern of the crest and its high degree of variability in different co-existing species, it supports the idea that the elaborate nasal cavity was likely used to produce sounds for communication. This study demonstrates the power of using an integrated approach combining 3D imaging, growth studies, and phylogenetic sampling to test ideas about the function and evolution of unusual structures in extinct animals.

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Fuel Cells Powered by Hydrogen from Sewage

Written by Megan Treacy


Researchers at the Oregon State University College of Engineering have discovered an efficient way to produce hydrogen from different types of biowaste, including municipal sewage.

The process uses 75% less energy than the traditional water electrolysis method of producing hydrogen, and can be done at a much lower cost, making it a good candidate for hydrogen fuel production. In the lab, researchers are already close to the Department of Energy’s goal of $2 to $3 per gasoline gallon equivalent for hydrogen fuel.

The university describes the process like this:

“In these systems, naturally occurring microorganisms from sewage attach to the surface of an anode and degrade the waste in the sewage, in a device that is something like a battery. The waste decomposes, eventually leaving protons that migrate to the cathode, combine with electrons and generate hydrogen.”

In addition to producing hydrogen, this process also cleans the water, so, ideally, treatment plants could be developed to take in sewage and send out hydrogen fuel and clean water. Imagine sewage becoming a valuable resource. The system can also be adapted to generate electricity directly instead of producing hydrogen.

Beyond hydrogen fuel cell vehicles, this technology could find practical use in developing countries or remote locations where waste treatment and power production are scarce.

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Could Solar Power Satellites Beam Down Gigawatts of Energy?

by Jeremy Elton Jacquot, Los Angeles

solar power satellite image

Image from NASA

How pie-in-the-sky is Ben Bova's space satellite scheme? Mr. Bova, the president emeritus of the National Space Society and a prolific science fiction author, penned a column in last Sunday's Washington Post calling on the next president to build an armada of solar power satellites (SPS) -- basically large accumulations of solar cells -- to help meet a substantial chunk of our energy needs. The idea of building orbiting solar systems in space is nothing new (see my posts about Japan's Space Solar Power Systems and India's space plans); the concept, as described by its creator, aerospace engineer Peter Glaser, would be a satellite in high orbit (where sunshine is always present) that would use microwave transmission to beam solar power to receiving stations on Earth.

The obvious benefit: a continuous 24-hour, 365-day supply of solar energy. Powered by solar energy itself, a single SPS could generate up to 10 gigawatts of power continually, according to Bova. If that's even remotely true, just imagine how much continuous power a group of these SPSs could provide.

The solar power satellite: a costly proposition
Things get a bit trickier when Bova delves into some of the cost issues. For instance, he says that an SPS could deliver electricity at a cost of only about 8 - 10 cents per kilowatt hour, which would make it very competitive with conventional power sources. He does recognize that the upfront costs -- both to build the satellite ($1 billion apiece) and to launch it (see: SpaceX launches) -- would be fairly substantial; launching it into space successfully would be a whole other story.

Over time, as economies of scale take hold and component prices drop, the scheme would begin to look much more appealing. How long that will take, though, is anybody's guess. We have the technologies in place -- solar, satellite and microwave -- but putting everything together (and making sure it all works) will be a tremendous challenge.

Assessing the potential spillover benefits
Such a large-scale project would definitely provide a boost to our ailing economy, creating both many new jobs and contracts for a variety of companies, and it would give NASA a worthy new pursuit. Bova suggests making NASA's primary goal the construction of a demonstration model SPS able to deliver 10 to 100 megawatts of power by the end of the president's second term. It's hard to imagine either a President Obama or President McCain having the stomach to fund such a project if it doesn't start making measurable progress sooner -- 8 years is a long time to wait for a technology that may not even work in practice.

Still, this project may also help spur interest in other space-related technologies and developments and could, in later years, create an entire new industry around space launchers. If you're interested in reading more about the history of the SPS, its technology and functional aspects, I recommend you read Wikipedia's (surprisingly) informative page on the topic. Or, better yet, get your hands on a copy of Ben Bova's "Powersat," a novel all about building the first SPS.

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Maryland to Sue U.S. Army Over Groundwater and Soil Contamination

(NaturalNews) The citizens of Maryland are fed up with the U.S. Army for failing to comply with a clean-up order issued by the U.S. Environmental Protection Agency (EPA) over a year ago, according to an article in the Baltimore Sun by Timothy B. Wheeler. Maryland Attorney General Douglas F. Gansler sent the Army notification that the state plans to sue under federal pollution law, because the Army has been too slow to clean up the mess caused by the careless disposal of fuel and munitions at their Fort Meade base. In August of 2007, the EPA gave the Army a legally-binding timetable, with fines for missed deadlines, to complete the clean-up process.

Army Wants to Take its Time Cleaning Up

While the Army says that it plans to comply with the clean-up order, they aren’t willing to comply with the time deadlines. Dave Foster, an Army spokesman, wouldn’t comment on the threatened lawsuit. He did say that "…the U.S. Army remains fully committed to protecting the health and safety of those living and working both on Fort Meade and in the surrounding communities."

EPA Says Dangers are Imminent and Substantial

Pentagon officials feel, according to Wheeler’s article, that the EPA is making too big of a deal over the toxic pollution. They claim that tens of millions of dollars have already been spent on getting their mess cleaned up, and they want to clean up the rest of it at their own pace. However, according to an article in the Washington Post by Lyndsey Layton, the EPA states that the toxins are an "imminent and substantial" danger, both to public health and the environment.

Remember Bush's 2000 Campaign Promise?

As Layton points out in her article, George W. Bush promised in his 2000 presidential campaign to ensure all federal facilities would comply with environmental law and "make them accountable." However, the Pentagon is not recognizing the EPA’s authority to enforce the clean-up schedule. John D. Dingell, Chairman of the House Energy and Commerce Committee, said, "I find it troubling, not only that the Department of Defense is in flagrant violation of final orders issued by the EPA, but that [the] DOD is now attempting to circumvent the law and Congress' intent by calling on the Department of Justice and the Office of Management and the Budget to intervene," according to the Washington Post. "The EPA is the expert agency charged by Congress with enforcing our environmental laws, and the Administration needs to allow them to do their job to protect the public health and safety."

25,000 Contaminated Sites Span all 50 States

The contaminants of concern at the Fort Meade base in Maryland include "cleaning solvents, pesticides, heavy metals, waste fuels and other hazardous chemicals," according to the Baltimore Sun. The Baltimore Sun also reports that recent studies have demonstrated that the groundwater is also contaminated with arsenic and perchlorate. The Pentagon is responsible for about 25,000 contaminated sites that span all 50 sites, according to Layton. Given the rampant groundwater contamination in the United States, it would certainly appear prudent for all those concerned with their health to be sure to install the best possible water filtration systems in their homes.

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Star-hugging planet is hottest and fastest found

The hottest planet ever found is a sizzling 2250 °C – as hot as some stars. The find could challenge models of how close planets can sidle up to their host stars.

The new planet, known as WASP-12b, is 1.5 times as massive as Jupiter. Incredibly, it takes just over a day to circle its host star, orbiting at 1/40th the distance between the Earth and the Sun. The tight embrace heats WASP-12b to an estimated 2250 °Celsius – about half as hot as the surface of the Sun, and as hot as some stars.

That makes the planet the hottest yet discovered, as well as the planet with the fastest orbit, says Leslie Hebb of the University of St Andrews in the UK.

Hebb and colleagues found the giant in a large survey called the Super Wide Angle Search for Planets (SuperWASP). The collaboration uses two sets of telescopes, one in Spain's Canary Islands and the other in South Africa, to search for signs of 'transiting' planets, which pass in front of and dim their host stars as seen from Earth.

Extrasolar planets are too dim compared to their host stars to directly measure the infrared light – or heat – they emit. But astronomers know the planets' size and orbital distances from the transit observations. From that, they can work out how much starlight falls on the planets and thus take their temperature.

The competition for the hottest planet is tight. WASP-12b only just beats out the last record-holder, HD 149026b, whose blacker-than-charcoal surface is a searing 2040 °Celsius.

Puffy planet

But WASP-12b's speedy orbit might be a harder record to break. Astronomers believe Jupiter-sized exoplanets form farther from their stars and then migrate to closer orbits. That's because there could not have been enough gas and dust so close to the stars to amass such giant worlds.

Most observed exoplanets have orbital periods of three days or longer, Hebb says, suggesting that some mechanism may prevent the planets from migrating even closer to their stars.

"When the planets form and migrate inward, something is causing them to stop and preferentially stop with a period of three days," Hebb told New Scientist. "I was surprised that the period could be so much shorter."

WASP-12b's size may also be a challenge to explain. The planet's width is 1.8 times that of Jupiter, larger than gas giants are thought to grow.

"The planet radius is suspiciously large," notes Sara Seager of MIT. "While observation is leading theory, it's uncomfortable to have a planet with a radius that cannot be accommodated by theory."

So far the team does not have an explanation, but radiation from WASP-12b's host star could be puffing up the planet, Hebb says. The planet's composition, which might be rich in metals like its host star, may enhance the effect. Planets rich in heavy elements are expected to be less dense than their 'metal-poor' cousins.

The team next plans to look for ultraviolet light emanating from WASP-12b. Such observations could reveal whether the planet's atmosphere is being stripped or evaporated away by its host star.

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Details Of Evolutionary Transition From Fish To Land Animals Revealed


A new study of Tiktaalik roseae (middle), a 375-million-year-old transitional fossil, highlights an intermediate step between the condition in fish like Eusthenopteron (bottom) and that in early limbed forms like Acanthostega (top). (Credit: Kalliopi Monoyios)

New research has provided the first detailed look at the internal head skeleton of Tiktaalik roseae, the 375-million-year-old fossil animal that represents an important intermediate step in the evolutionary transition from fish to animals that walked on land.

A predator, up to nine feet long, with sharp teeth, a crocodile-like head and a flattened body, Tiktaalik's anatomy and way of life straddle the divide between fish and land-living animals. First described in 2006, and quickly dubbed the "fishapod," it had fish-like features such as a primitive jaw, fins and scales, as well as a skull, neck, ribs and parts of the limbs that are similar to tetrapods, four-legged animals.

The initial 2006 report did not describe the internal anatomy of the head, because those parts of the fossil were buried in rock. In the October 16, 2008, issue of Nature, the researchers describe this region and show how Tiktaalik was gaining structures that could allow it to support itself on solid ground and breathe air.

"We used to think of this transition of the neck and skull as a rapid event," said study author Neil Shubin, PhD, of the University of Chicago and Field Museum and co leader of the project, "largely because we lacked information about the intermediate animals. Tiktaalik neatly fills this morphological gap. It lets us see many of the individual steps and resolve the relative timing of this complex transition."

"The braincase, palate, and gill arch skeleton of Tiktaalik have been revealed in great detail by recent fossil preparation of several specimens," said Jason Downs, PhD, a postdoctoral research fellow at the Academy of Natural Sciences and lead author on the new study. "By revealing new details on the pattern of change in this part of the skeleton, we see that cranial features once associated with land-living animals were first adaptations for life in shallow water."

"The new study reminds us that the gradual transition from aquatic to terrestrial lifestyles required much more than the evolution of limbs," said Ted Daeschler, PhD, of the Academy of Natural Sciences and co-leader of the team that discovered Tiktaalik. "Our work demonstrates that, across this transition, the head of these animals was becoming more solidly constructed and, at the same time, more mobile with respect to the body." These changes are intimately associated with the change in environment.

Fish in deep water move and feed in three-dimensional space and can easily orient their body in the direction of their prey. A neck, seen for the first time in the fossil record in Tiktaalik, is advantageous in settings where the body is relatively fixed, as is the case in shallow water and on land where the body is supported by appendages planted against a substrate.

Another important component of this transition was the gradual reduction of the hyomandibula, a bony element that, in fish, coordinates the cranial motions associated with underwater feeding and respiration. In the transition to life on land, the hyomandibula loses these functions and the bone becomes available for an eventual role in hearing.

In humans, as in other mammals, the hyomandibula, or stapes, is one of the tiny bones in the middle ear. "The bony part of Tiktaalik's hyomandibula is greatly reduced from the primitive condition," said Downs, "and this could indicate that these animals, in shallow water settings, were already beginning to rely less on gill respiration."

The discoveries were made possible by laboratory preparators Fred Mullison and Bob Masek, who prepared the underside of the skull of specimens collected in 2004. This painstaking process took several years. This work showed the underside of the skull and gill bones "beautifully preserved," said Shubin, "to a degree unlike any creature of its kind at this transition."

Having multiple Tiktaalik specimens enabled the researchers to prepare the fossils in ways that showed the bones of the head in "exceptional detail," Downs said.

The team discovered Tiktaalik roseae on Ellesmere Island, in the Nunavut Territory of Canada, 600 miles north of the Arctic Circle. Though this region of Nunavut is now a harsh Arctic ecosystem, at the time that Tiktaalik lived, the area was much further south and was a subtropical floodplain ecosystem.

The formal scientific name for the new species, "Tiktaalik" (tic-TAH-lick), was derived by the Elders Council of Nunavut, the Inuit Qaujimajatuqangit. The Inuktikuk word means "a large, shallow-water fish." The paleontology team works in Nunavut with authorization from the Department of Culture, Language, Elders and Youth. All fossils are the property of the people of Nunavut and will be returned to Canada after they are studied.

The fossil research in Nunavut is carried out with authorization from the Department of Culture, Language, Elders and Youth, Government of Nunavut. All fossils are the property of the people of Nunavut and will be returned to Canada after they are studied.

A cast of Tiktaalik, along with a fleshed-out model of the animal, are on display in the Evolving Planet exhibition at Chicago's Field Museum, where Shubin serves as Provost.

The research was supported by private donors, the Academy of Natural Sciences, the Putnam Expeditionary Fund (Harvard University), the University of Chicago, the National Science Foundation, and the National Geographic Society Committee for Research and Exploration.

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An End to Paralysis with Artificial Brain-to-Muscle Connectors

Using a computerized connector between the brain and muscles in the body, scientists have been able to restore movement to paralyzed limbs. A group of neuroscientists report in Nature today that they used a brain-computer interface to join the motor cortex of an ape to the muscles in its wrist. After scientists paralyzed the ape's arm temporarily, it was still able to make its wrist move my sending electrical impulses directly from its brain to the muscles, bypassing the damaged nerves in between. The study has profound implications for people whose nerves have been severed or damaged, leaving them paralyzed.

What's particularly interesting about this research is that it shows the versatility of the motor cortex when combined with a brain-computer interface (BCI). Previous research showed that people could learn to move a cursor on screen by linking to specific areas of the motor cortex. This new study showed that any area of the motor cortex could be "repurposed" to activate muscles in the body via BCI.

Say the researchers:

Until now, brain-computer interfaces were designed to decode the activity of neurons known to be associated with movement of specific body parts. Here, the researchers discovered that any motor cortex cell, regardless of whether it had been previously associated with wrist movement, was capable of stimulating muscle activity. This finding greatly expands the potential number of neurons that could control signals for brain-computer interfaces and also illustrates the flexibility of the motor cortex.

Human implementations for the technology are at least a decade away, but this discovery could be a game-changer for dealing with paralysis. One possibility would be to connect the motor cortex with an area of the spine below an injury. Signals would be re-routed around the damaged spinal cord, and could allow the brain to regain control of the paralyzed body parts affected by the injury.

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Did a Mutation Give Humans Thought? -Scientists Say "Yes"


Chp_black_brain_1 Although humans and chimpanzees genetically vary by just 1.2 percent, that small percentage makes a world of difference in the mental and linguistic capabilities between the two species. A study shows that a certain form of neuropsin, a protein that plays a role in learning and memory, is expressed only in the central nervous systems of humans. The scientists conclude that this critical difference originated less than 5 million years ago.

Dr. Bing Su of the Chinese Academy of Sciences in Kunming, China, and other researchers analyzed the DNA of humans and several species of apes and monkeys. Previously they had found that type II neuropsin, a longer form of the protein, is not expressed in the prefrontal cortex (PFC) of lesser apes and Old World monkeys. In the new study, they tested the expression of type II in the PFC of two great ape species, chimpanzees and orangutans, and found that it was not present in these closely related species either. Since these two species diverged most recently from human ancestors (about 5 and 14 million years ago respectively), this finding demonstrates that type II is a human-specific mutation and originated relatively recently.

The researchers note that more studies should look further into the biological function of type II neuropsin in humans, in order to understand the genetic basis that underlies the traits that set humans apart from nonhuman primates.

*The study was published online in Human Mutation, the official journal of the Human Genome Variation Society.

Posted by Rebecca Sato

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Facebook is 'social glue' for university freshers

The University is now exploring ways of using internet platforms that most students are familiar with -- social networking sites and podcasting -- to help new arrivals get their bearings.
And it is looking into how these technological mediums might also be used to improve the student experience beyond the first few weeks at university.

The work is focussing on two areas:

-- Building on the findings of a study that has concluded that "Facebook is part of the social glue that helps students settle into university life".

-- Launching a new website that provides podcasts of students talking about their experiences of settling in to university life, covering everything from finding accommodation to coping with debt. This is available at www.StartingUni.info

The University of Leicester's own Facebook network lists 10,000 members, including current and past students and staff. A research project, funded by the Registrar and Secretary of the University and its Teaching Enhancement Fund, was launched to find out more about how students were using Facebook at university, and how it helps them integrate into university life.

The study was conducted by Dr. Jane Wellens from the University's Staff Development Centre, Dr Clare Madge from the Department of Geography, Dr Tristram Hooley from CRAC: The Career Development Organisation and Dr Julia Meek from Lifecycle Evaluation.

The researchers state: "We know little about how this phenomenon impacts on the student experience and, in particular, if and how it facilitates new students' social integration into University life. Our project focused on how pre-registration engagement with the University of Leicester Facebook network influences students' post-registration social networks and their understanding of the University. It also explored whether there is any role for social networking tools to be used by University support services and academic departments to enhance the social and academic integration of students."

A survey of 221 first year students conducted between April and June this year found that more than half (55 per cent) had joined Facebook to make new friends prior to entering university, while a further 43 per cent joined immediately after starting university. Nearly three quarters said Facebook had played an important part in helping them to settle in at university.

Over a third of respondents also said they used Facebook to discuss academic work with other students on a weekly basis, and more than half responded positively to the idea of using Facebook for more formal teaching and learning – although only 7 per cent had actually done so. Many suggested ways in which Facebook could be used, such as providing social support for students in departments and informing students about changing lecture times.

But the survey also found that 41 per cent of students were against being contacted directly by tutors via Facebook. A report on the preliminary findings warns that the university will need to tread carefully if it wants to use Facebook to communicate with students for administrative or teaching and learning purposes.

The researchers say: "The survey data illustrate that Facebook is part of the 'social glue' that helps students settle into university life, that keeps the student body together as a community and which aids in communication (especially about social events) between the student body. However, care must be taken not to over privilege Facebook: it is clearly only one aspect of student's social networking practices and clearly face-to-face relationships and interactions remain significant.

"A clear picture is emerging whereby the students thought the use of Facebook was most importantly for social reasons, not for formal teaching purposes. Although it was sometimes used informally for learning purposes by students, they were not overly keen on the idea of being contacted by their tutors via Facebook. Just under half of the respondents considered it to be acceptable for the University to be contacting them for teaching, marketing or pastoral matters but less than one third were happy to be contacted for administrative matters."

The team that conducted the research is now beginning a second phase of the study involving in-depth interviews to explore ways in which the university might subtly use Facebook and other web-based platforms to enhance the student experience, without making students feel like their virtual social space is being invaded.

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Cancer of the Devil


Last week, the International Union for Conservation of Nature (IUCN) released its latest report on the state of the world’s species. It makes for gloomy reading. Although there have been a few triumphs — species increasing their numbers thanks to conservation efforts — the general picture is one of decline. A quarter of all mammal species are now endangered, mostly because their habitat is disappearing. But of all the mammals now on the endangered list, from the fishing cat to the Caspian seal, the most startling is the Tasmanian devil.

Tasmanian devilTasmanian Devil (Sarcophilus harrisii) (Ian Waldie/Getty Images)

Tasmanian devils live on the island of (surprise!) Tasmania, off the south coast of Australia. They are marsupials: their young are born tiny (about a third of a gram — that’s a hundredth of an ounce), then fed on milk and carried in a pouch. As adults, devils are thick-set, thuggish-looking animals, with massive teeth that they use to chomp up carcasses, bones and all. Although they are far from enormous — the biggest males weigh in at around 14 kilograms (30 pounds), about the size of a French bulldog — Tasmanian devils are the largest carnivorous marsupials to have, so far, escaped extinction.

But over the last 12 years, the population has crashed — in some areas, population numbers have fallen by 90 percent. The dramatic decline has led the IUCN to move the species from “least concern” a decade ago to “endangered” now. Some think it could be extinct within 25 years. The reason? An infectious cancer.

Some human cancers are infectious in the sense that they are caused by infectious viruses. Cervical cancer, for instance, is caused by human papilloma virus, which spreads from one person to another during sex.

But the cancer that’s killing the Tasmanian devils is different. The cancer cells themselves are infectious.

Here’s what happens. The cancer causes a tumor on the animal’s face. If an infected animal bites another — which happens often, as devils are aggressive creatures, especially during the mating season — some of the tumor cells get transferred. These then start growing on the other animal. It’s as though you kissed someone with throat cancer, and got their cancer yourself.

Which is pretty weird. Cancers are usually part of you, a group of your own cells that begin to grow out of control. Foreign cells — such as the ones that cause the devils’ cancer — are normally rejected by the immune system. That’s why organ transplants are difficult: the immune system immediately recognizes that the transplanted organ is not part of you, and begins attacking it. This happens unless there’s a close match between the donor and the recipient at a set of genes known as the major histocompatibility locus, or MHC. If there is a match, you may be similar enough, genetically speaking, that the immune system doesn’t notice the difference between the foreign organ and you. But unless you’re having a transplant from a close relation, the odds of this are low. Human MHC genes are extremely variable. Most people who get organ transplants thus have to take drugs that suppress their immune system. Otherwise, the foreign organ gets attacked and destroyed.

So it’s not surprising that most of the devil-style infectious cancers known in humans have happened when someone’s immune system hasn’t been working. Recipients of transplanted organs occasionally receive cancer cells as well; the drugs that prevent the immune system from destroying the organ also prevent it from destroying the foreign tumor. Because a baby’s immune system doesn’t get going until after it’s born, a pregnant woman with cancer can infect her fetus. Likewise, if a mother is carrying several fetuses and one of them has a cancer, it can infect the others. But all these events are rare.

Even rarer are cases of direct transmission to someone whose immune system is robust. One example: a healthy surgeon injured his hand while operating on a cancer patient and contracted the patient’s cancer. For reasons unknown, his immune system failed to respond. The resulting tumor was cut out, and the surgeon survived.

Tasmanian devils are not so lucky. Devil facial tumor disease, as it is known, kills within months. The tumor makes it hard for the animals to feed, so they starve.

The cancer has had a dramatic impact on their way of life. In the past, a female Tasmanian devil could expect to live to four or five. She’d start breeding at two, and have a litter every year. But in places where devil facial tumor disease has struck, life expectancy is short. Hardly any animals live beyond age three, and most females have only one chance to breed.

Interestingly, many females are now starting to breed in their first year. Although, before the disease, a few first-year females would manage to breed, most wouldn’t. This has changed. In some populations, more than 80 percent of females are breeding in their first year. But in the absence of animals able to resist the disease, whether this will be enough to save the species from annihilation remains to be seen.

Why don’t the devils reject the alien cells? There are two possibilities. The first is that the tumor somehow interferes with the immune response. (Many traditional tumors can do this.) The second is that the immune system fails to recognize the tumor as alien.

In the case of the devils, it seems to be the second. The animals don’t have much genetic diversity at the MHC. So the immune system doesn’t seem to be able to detect the invading cells because they’re not different enough from the animal’s own body. (Other animals with low MHC diversity, such as pocket gophers, can sometimes accept organ transplants from an unrelated member of their species.)

Tasmanian devils aren’t the only animals to have a transmissible cancer. Dogs have one too. Theirs is transmitted during sex. Canine transmissible venereal tumor has been around for at least 200 years, and probably much longer. (The devils’ disease, in contrast, was first spotted in 1996.) For dogs, the disease is rarely fatal. Instead, the tumor goes through an initial period of rapid growth, during which it manages to stop the dog’s immune system from attacking it. But then, the immune system gets going, and kills the tumor. Having once been infected, a dog is resistant to the disease.

These cancers raise a number of questions. In particular: why aren’t more cancers transmissible? After all, there are many, many types of cancer in many different species, but only two are known to spread from one animal to another. This suggests it isn’t simply a matter of MHC diversity. After all, animals such as beavers and cheetahs have low diversity but no cancer; and the MHC situation of Tasmanian devils didn’t suddenly change in the 1990s. Instead, it suggests that the cancer cells have to evolve in ways that makes them more likely to be transmissible. What those ways are, however, is a total mystery.

But if transmissible cancers have evolved twice, the odds are they can evolve again. The prospect is unnerving. (Even more unnerving is the idea that such cancers could be transmitted by mosquitoes, as was mooted for an infectious cancer said to be circulating among a species of hamster in the 1960s. Reports of this cancer are, however, absent from the recent scientific literature, and their significance is unclear.) Beavers and cheetahs, and other animals with low diversity at the MHC, could obviously be at risk of going the way of the devil, should a transmissible cancer evolve in these species.

What about us? Humans have lots of MHC diversity. But we have another risk factor. Owing to the failure to treat H.I.V., the virus that causes AIDS, in many parts of the world, large numbers of people have compromised immune systems. This is the sort of environment that could, perhaps, allow a transmissible cancer to evolve. Initially, it would circulate only among those who are immunocompromised. But, over time, it might evolve to infect healthy people too. It’s an alarming thought — though happily, a thought is all it is. For now.

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1366 Technologies Opens Innovative Solar Manufacturing Facility

Green Your Junk: 16 Creative Ways to Upcycle Before You Recycle

by Mike Sowden


The recyclers are out in force. Whether it's using a local recycle centre or a council-provided green bin, it's never been easier to get your household waste processed back into useful raw materials. But that takes energy - and why spend that energy when this "rubbish" can be turned into something useful in its present form?

Here are some of our suggestions for making the most of what you have already.

"Grease the inside of a pan", so many recipes start. The best way to do this is with butter-smeared greaseproof paper - the kind butter is wrapped in. So always have some handy by storing your used butter paper in the fridge (you can even freeze it if you're overflowing).


Big fan of bacon? (Organic, of course!) All that liquid fat running down the plughole will probably be slowly constricting the drain of your sink. A better option is to pour it into a jar, add unwanted food crumbs and a length of string, refrigerate and hey presto! - bird cake to hang from the washing line.


There are plenty of things to do with old clothes that aren't wearable any more, such as turn them into dusters or a quilt. But if you want to make the greenest use of them that you can, turn them into wrapping paper (or rather wrapping cloth), the Japanese way. A great way to say "sayonara" to all that expensive gift paper.


Milkbottles. No, I know it's obvious, but I have to say it - I've walked past recycling bins with milk bottles in them. It's an easy trap to fall into: they're glass bottles, so they can be recycled, so into the green bins they go. Except there's a far more economical way to reuse them...


I'm not a big fan of paper towels, except in one respect - what's in the middle. Those cardboard tubes make terrific cable tidies! (You can also achieve the same effect by slotting toilet roll carboard tubes together in series). Bundle your excess lengths of cable into them, and tie them with string. You can even label them by writing on the outside of the tube - a boon if your home or office is overflowing with geeky cables and wires.


Now here's a phrase that needs a bit of redefining: food waste. Most of what we trim off our food can go into making stock that's leaps and bounds ahead of anything that came out of a freeze-dried cube. And the remainder can feed the garden by becoming compost.


There's nothing more depressing than unpacking acres of plastic from a new purchase to get to the contents. So why not put all your unwanted newspapers, magazines and junk mail to good use instead of putting them in a recycling bag? Scrunched up, they make just as good packing material as those non-degrading foam chips or reams of bubble wrap.


Speaking of junk mail - namely envelopes, letters and flyers - it's a great source of paper for telephone notebooks or shopping lists. Chop up (into, say, A5 sized pages) and bind with a strong needle and some string. Or if you have a fire, a few pages twisted together make great firelighters. Let your imagination run wild - like these people.


All brushes have a shelf-life - but there are many shelves to put them on. Take make-up brushes - fine and soft enough to dust your camera lens. I also have a couple of worn toothbrushes I've kept to clean the chain of my mountain-bike. Brushes are bristling with reuse potential. (Sorry).



If your furniture is looking so chipped, scuffed and scratched that even the best varnish can't do much for its appearance - why not spray paint it? Another advantage is that you can hide some pretty major repair work with a clever lick of paint. And if the results aren't fit for the house, how about the garage or toolshed?



Okay, I'm going to cheat a little. Because however much I like the idea of us all being able to turn our irrepairably dog-eared books into the kind of sculptural wizardry you can see at WebUrbanist, turning books into Art is a tall order (although here's a good way to start). But what about using them to make artistic wall art, or even wallpaper? Book pages artificially yellowed (by leaving them in the sun, or very carefully baking them in an oven at a low temperature) make terrific faux-antique wall decoration.


Oops - butterfingers. And now there's the remains of a plate in a sad pile of swept-up pot fragments, ready for the trash. But are you planning to pot any plants in the near future? Line the base of each pot with some of these fragments - they let water drain out the hole in the base without carrying away the soil. Or have you ever wondered how it felt to be an ancient Roman? Your first mosaic awaits.


I suspect that ironing board covers and oven mitts are pretty much the same heat-retardant material. That means if one falls to pieces, those pieces could be used to patch up the other - or, in the case of an ironing board cover, make the other, in the form of a lovely new pair of mitts.

Used coffee grounds, in moderation, can do wonders for the garden by adding nitrogen to the soil. Starbucks promote this through their eco-admirable "Grounds for your Garden" scheme (it's a shame some of their other practices aren't so benevolent). Or maybe try one of these alternate uses, courtesy of Casey Nicholson at HowToDoThings.


Breakfast cereals almost always come in cardboard boxes containing a plastic cereal bag. Open it carefully - because it makes a terrific freezer/food bag. You can also grease it a little and use it to line the bottom of baking dishes. And it's just the right size to store butter paper (see above).


Wine bottles are destined for the bottle bin...or are they? Look at what those clever people at transglass did with theirs. You can do better? That's the spirit!

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Adding the 'Nasty Nine' to the 'Dirty Dozen'

Scientists working for the United Nations Environment Program are reviewing nine chemicals that could be added to the original "dirty dozen" list of banned toxic chemicals.

The Stockholm Convention on Persistent Organic Pollutants banned nine pesticides, as well as common chemicals like PCBs and dioxin. All were banned because they accumulate in the tissues of living things, including humans, because they are all but indestructible once released into the natural world, and because they can spread across the globe with weather patterns and migrating animals. Not to mention that they have been linked to a range of health issues, including cancer and reproductive and developmental problems.

“Chemicals have contributed to human well-being across a range of areas from medicine and foodstuffs to agriculture and industrial processes,” said Achim Steiner, executive director of the UN Environment Program. “However, as science gains greater insight into their effects, we are fast understanding that some substances now pose real risks to humans and the wider environment, often invulnerable communities such as can be found in parts of the Arctic. Eliminating, restricting and accelerating a switch to better alternatives must be our goal.”

The new candidates are used in consumer products, such as flame retardants in textiles and carpets, in fire-fighting foam, and in photo imaging.

Here's a look at the new candidates:

The Nasty Nine

  1. Pentabromodiphenyl ether
    This PBDE congener, sometimes referred to as "penta," was used as a flame-retardant in foam upholstery and furnishing. It was fist banned in Germany, Norway and Sweden in the 1980s and 1990s, then in the Europe Union in 2003. The last U.S. manufacturer stopped producing the chemical in 2005, and the Environmental Protection Agency subsequently banned its production in the U.S. It is still manufactured elsewhere, primarily in China, and can be imported to the U.S. Maine and Washington have banned it and nine other states have proposed bans.

    The chemical may cause a range of health problems, including liver disease and reproductive and developmental problems. It has been found in human breast milk.

  2. Octabromodiphenyl ether
    Like its sister "penta" this polybrominated diphenyl ether, or PBDE, has been linked to health issues and has largely been phased out in developed nations.

  3. Chlordecone
    This insecticide, also known as Kepone, was used until 1978 in the United States on tobacco, ornamental shrubs, bananas, and citrus trees, and in ant and roach traps. It is chemically almost identical to Mirex, which was one of the original "Dirty Dozen" banned by the treaty.

    Workers using chlordecone suffered damage to the nervous system, skin, liver, and male reproductive system. It may still be in use in developing nations, despite its being banned in the industrialized world.

  4. Lindane
    An agricultural insecticide also used to treat headlice and scabies in people, lindane has been banned in 50 nations because the organochlorine pesticide can attack the nervous system. In the United States, it was used until 2007 on farms, and it is still used as a "second-line" treatment for head lice when other treatments fail.

    Additionally, because Lindane is the only useful product in a family of chemicals generated to produce the pesticide, there is persistent chemical waste created by the process. For every ton of Lindane produced, six to 10 tons of waste are produced.

  5. Alpha-hexachlorocyclohexane
    One of the persistent chemical waste products produced by making Lindane, alpha-hexachlorocyclohexane may cause cancer, and liver or kidney problems.

  6. Beta-hexachlorocyclohexane
    Another of the persistent chemical waste products produced by making Lindane, beta-hexachlorocyclohexane may cause cancer and reproductive problems.

  7. PFOS
    The company 3M used PFOS to make Scotchgard fabric and other stain-resistant products until 2002. The chemical is found in the bodies of people around the world, and in relatively high concentrations in Arctic wildlife -- reflecting the global transport of persistent chemicals like these.

  8. Hexabromobiphenyl
    A polybrominated biphenyl, or PBB, hexabromobiphenyl is a flame retardant that has been linked to a range of health problems, including weight loss, skin disorders, nervous and immune systems effects, and effects on the liver, kidneys, and thyroid gland. While it is no longer used in developed nations, it may still be in use in developing nations.

  9. Pentachlorobenzene
    Used in the manufacture of an insecticide, and as a flame retardant, Pentachlorobenzene may damage the nervous and reproductive systems, as well as the liver and kidneys. It is also used as a head lice treatment, and can be found in the waste streams of some paper mills, petroleum refineries, sewage treatment plants and incinerators.

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