Less than 24 hours after the shootings at Northern Illinois University, "domain prospectors" went to work registering various Web site addresses they hoped to sell later for a profit.
Among the addresses snapped up just after the attacks were several sites using words in conjunction with NIU that could come up through Google or another search engine. One of them currently features several paid advertisements and a photograph of a black- jacketed coroner standing behind police tape.
Such sites can compete with or often be confused with sites endorsed by people actually involved with the university. NIU has a memorial page on its Web site at www.niu.edu/memorial. The page features photographs, biographies of the victims and links to support services for students and their families.
Because it's difficult to know who owns a Web site, authorities stress that official memorial pages like NIU's are the best place to make donations or other contributions. Although it's good to be cautious, simply visiting a Web site will typically not contribute materially to the site's owner, as long as visitors don't click on any paid advertisements that might be posted there.
Domain prospectors live anywhere in the world, and they often try to mask their identities. The sites usually attract so-called "placeholder ads" placed automatically by the hosting service before a domain is fully developed, though the ads don't generate revenue unless a user clicks on them.
Domain prospecting, and its more malicious and often illegal cousin "cybersquatting," have been around since the earliest days of the Internet. Initially, speculators began registering domain names that were likely to become valuable as the Web took off. Some early pioneers actually became very wealthy through this practice.
In 1999, Congress passed a law making it illegal to deliberately purchase domains that contain registered trademarks or proper names. But otherwise, anyone can register a domain for as little as $10, leaving plenty of room for profit.
After the school shootings at Virginia Tech in 2007, dozens of domain names were registered and subsequently auctioned off. A few of these domains became memorial sites, including bloodbathinvirginia.com, which became a home for an organization promoting gun control.
Arizona resident Warner Tavares registered a domain name related to the Virginia Tech killings on April 16, 2007, the same day of the attacks. Contacted for this story, Tavares acknowledged he originally hoped to profit from the purchase, but he said he soon regretted his decision.
"It all happens very fast, but that one definitely bothered me a little bit," he said. "I decided to let it expire. I mean, we're human, too."
Nonetheless, the domain name remains available for sale at a price of $1,300. The Web site contains a notice that a portion of the proceeds would go to the families of victims, but it doesn't specify how much.
Internet Domain Prospectors Try to Capitalize After Tragic Events
Face transplant 'double success'
Successful results from two more face transplants will speed progress towards similar operations in other countries, say experts.
The Lancet journal reported operations involving a bear attack victim in China, and a French patient with a massive facial tumour had taken place.
The Chinese patient was given not just the lip, nose, skin and muscle from a donor, but even some facial bone.
Specialists in London are working towards the UK's first transplant.
Frenchwoman Isabel Dinoire became the world's first face transplant patient in 2005 after being savaged by a pet dog. She described the results of the operation as a "miracle".
The latest operations were just as complex, but involved different challenges for French and Chinese surgeons.
The first operation took place in April 2006. The patient was a farmer from a remote village in Yunnan province in China, who had been attacked by a bear 18 months earlier, leaving a huge section of tissue missing from the right side of his face.
The operation, at Xijing Hospital in Xi'an City, used the face of a 25-year-old man who had died in a traffic accident.
Despite immune-suppressing treatment, the patient had to battle his body's attempt to reject the new tissue on three occasions.
His doctors said they now believed that face transplantation was a viable long-term option.
The second operation, carried out in Paris in January 2007, involved a 29-year-old man disfigured by a neurofibroma, a massive tumour growing on his facial nerves.
Its removal was timed to coincide with a face transplant, and a year later, doctors again declared the operation a success.
The patient told them that previously he had been considered a "monster", but now felt like an anonymous person in the crowd.
The procedure, they said, had moved "from ethical debate to surgical reality".
Moving forward
In the UK, surgeons at the Royal Free Hospital in London are making preparations to carry out the operation if the right combination of patient and donor becomes available.
Professor Iain Hutchison, a consultant oral and maxillofacial surgeon at Barts and the London Hospital, and founder of the "Saving Faces" charity, said that the twin successes would offer more encouragement for surgical teams considering carrying out their own operations.
He said: "This takes a step forward in two ways - firstly the use of bone as well as skin - and next is carrying out this operation on someone with a benign tumour.
"There will always be limitations to this - the main one would be a societal constraint - a lack of suitable donors.
"However, there is certainly demand for this, with the major area being for people with facial burns."
Roger Green, president of the British Association of Plastic, Reconstructive and Aesthetic Surgeons, said: "This particular surgery is a way of giving back a life to a patient who has been horribly scarred by burns, trauma or a tumour.
"However, we must acknowledge the long-term medical risks, such as transplant rejection and the need for life-long medication, associated with the procedure. There is also the potential of psychological impact following such a transplant."
Sub to make deep Caribbean dive
Scientists are set to explore the world's deepest undersea volcanoes, which lie 6km down in the Caribbean.
Delving into uncharted waters to hunt for volcanic vents will be Autosub6000, Britain's new autonomously controlled, robot submarine.
Once found, the life, gas and sediment around the vents - the world's hottest - will be sampled and catalogued.
The research will be carried out by a British team aboard the UK's latest research ship, the James Cook.
"We are heading out on two expeditions, each close to a month long, to map the full length of the Cayman Trough," said team leader, Dr Jon Copley of the National Oceanography Centre in Southampton (NOCS).
Dr Copley explained that the Cayman Trough, which lies between Jamaica and the Cayman Islands, is a product of the Caribbean tectonic plate pulling away from the American plate.
"It is the world's deepest volcanic ridge and totally unexplored," the Southampton-based researcher told BBC News.
Along with Autosub6000, the researchers will also rely on Isis, the UK's deepest-diving, remotely operated vehicle to scan the deep.
Double Sub
First overboard will be Autosub6000, an unmanned undersea vehicle that can go down to 6,000m and carry out a dive without being controlled from the surface.
It will be tasked with finding the volcanic vents on the ocean floor.
The second submarine to take the plunge will be the Isis.
Isis will sample fluids and sediments from around the lip of the vents to test their geochemistry, and also collect animal specimens."We are hoping to find several different types of vents along the ridge," said Dr Copley.
"Some of the vents will be very similar in depth to the vents we already know about, and because the conditions will be alike, we might expect very similar animals," he explained.
The researchers will look to compare the animals around the Cayman vents with those in the Atlantic and Pacific, in the hope of better understanding the processes that affect how deep-sea creatures "get about".
If the organisms in the Cayman Trough look like those from other deep volcanic trenches, it will suggest that ocean currents must play a role in shaping the patterns of deep-sea life by transporting the animals' larvae around.
However, if the Cayman Trough animals are very different from those existing in other parts of the Earth's oceans then isolation will be considered more important.
"The deep ocean is our planet's largest ecosystem. If we are going to use its resources responsibly then we need understand what determines its patterns of life," the Southampton-based researcher said.
New vents
Dr Copley told BBC News that there was also another kind of venting that was driven by a very different geological process in which the Earth's mantle is directly exposed to the water.This type of volcanism has only ever been seen once before, in the mid-Atlantic.
The temperatures around these hydrothermal vents were so hot because they were so deep, Dr Copley said.
"They could be hotter than 500C (930F), and if they are that hot, they will probably have quite different chemistry and life forms - we expect to find new species."
The researchers expect that, at depths greater than 3,000m, one in every two animals they come across will be a species new to science.
DNA tests to study mummy fetuses in King Tut tomb
Egyptian scientists are carrying out DNA tests on two mummified fetuses found in the tomb of King Tutankhamun to determine whether they are the young pharaoh's offspring, the antiquities authority said on Wednesday.
The two tiny female fetuses, between five to seven months in gestational age, were found in King Tut's tomb in Luxor when it was dissevered in 1922.
DNA samples from the fetuses "will be compared to each other, along with those of the mummy of King Tutankhamun," the head of the Supreme Council of Antiquities, Zahi Hawass, said in a statement.
The testing is part of a wider program to check the DNA of hundreds of mummies to determine their identities and family relations. Hawass said the program could help determine Tutankhamun's family lineage, which has long been a source of mystery among Egyptologists.
The identity of Tut's parents is not firmly known. Many experts believe he is the son of Akhenaten, the 18th Dynasty pharaoh who tried to introduce monotheism to ancient Egypt, and one of Akhenaten's queens, Kiya. But others have suggested he was the son of a lesser known pharaoh who followed Akhenaten.
Scholars believe that at age 12, Tutankhamun married Ankhesenamun - a daughter of Akhenaten by his better known wife Nefertiti - but the couple had no surviving children. There has been no archaeological evidence that Tut, who died around the age of 19 under mysterious circumstances over 3,000 years ago, left any offspring.
Tutankhamun was one of the last kings of Egypt's 18th Dynasty and ruled during a crucial, turmoil-filled period when Akhenaten's monotheism was ended and powers were returned to the priests of ancient Egypt's multiple deities.
The council said that if the tiny mummies are unrelated to Tut, they may have been placed in his tomb to allow him to "live as a newborn in the afterlife."
Ashraf Selim, a radiologist and member of the Egyptian team, said the tests could take several months. So far, the team has carried out CT scans on the two fetuses and taken samples for DNA tests.
"We want to find out the truth and facts relevant to the history of these kings," Selim told The Associated Press.
Since they were found in King Tut's tomb, the mummified fetuses were kept in storage at the Cairo School of Medicine and were never publicly displayed or studied, Selim said.
Hawass has announced ambitious plans for DNA tests on Egyptian mummies, including tests on all royal mummies and the nearly two dozen unidentified ones stored in the Egyptian Museum in Cairo. He has said the tests may show that some royal mummies on display are not who archaeologists thought them to be.
One of his top goals is to find the mummy of Nefertiti, the queen legendary for her beauty.
Last year, Egypt announced that archaeologists had identified the mummy of Hatshepsut, Egypt's most powerful queen and the only female pharaoh. But scientists later said they were still analyzing DNA from the bald, 3,500-year-old mummy to try to back up the claim.
Hawass has long rejected DNA testing on Egyptian mummies by foreign experts, and only recently allowed such projects on condition they be done exclusively by Egyptians. A $5 million DNA lab was created at the Egyptian Museum, with funding from the Discovery Channel.
But some experts have warned that Hawass is making claims like that of Hatshepsut too quickly, without submitting samples to a second lab to corroborate DNA tests or publishing the results in peer-reviewed journals, both common practice.
The council announced in its statement Wednesday that the government had agreed with Cairo University's Faculty of Medicine to open a second DNA testing lab, though it did not give details on funding for the lab or when it could begin work.
Abdel-Halim Nour el-Deen, a former head of the council and a leading Egyptologist said DNA testing on mummies thousands of years old is very difficult.
"It is doubtful that it could produce a scientific result to determine such important issues such as the lineage of pharaohs," Nour el-Deen told the AP.
Nour el-Deen also criticized the antiquities authority for not making public the results of the tests already carried out.
Global warming to boost kidney stone rates
New research suggests that rising temperatures and increased dehydration linked to global warming will boost kidney stone rates around the world.
In the United States in particular, hotter weather will lead to a dramatic rise in kidney stone disease among residents of southern states the so-called "kidney-stone belt". This will result in an increase of 1.6 million to 2.2 million additional kidney stone cases by 2050, according to the study.
"This is an example of how global warming will affect people directly," said study author Tom Brikowski, an associate professor with a specialty in hydrology in the department of geosciences at the University of Texas at Dallas.
The study authors stressed that the exact degree of the increased risk remains unclear. But, Brikowski added: "We are certain that warming will increase, and that the rate of kidney stone disease will go up."
The findings are reported in this week's issue of the Proceedings of the National Academy of Sciences.
Brikowski and his colleagues said the "kidney-stone belt" currently includes Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina and Tennessee. But with global warming, the risk of kidney stone disease could ultimately touch a much wider swath of states, stretching from Kentucky all the way to northern California, the researchers said.
According to the US National Kidney and Urologic Diseases Information Clearinghouse, about 5 percent of Americans develop kidney stones at some point, with the risk rising as men and women enter their 40s and 50s, respectively.
Typically composed of calcium and other minerals found in urine, a kidney stone is a hard, crystallised mass that passes - often painfully - through the urinary tract. Drinking too little fluid and/or dehydration can lead to development of a stone, as can a metabolic predisposition for kidney stone disease, known as nephrolithiasis.
To gauge the potential impact of global warming on kidney stone risk, the researchers analysed two prior kidney stone studies that had plotted disease incidence by US geographic regions, along with federal reports assessing global warming patterns. The researchers then developed two mathematical models to compute all the information. Both models predicted that the current "kidney-stone belt" would expand and that overall incidence will rise.
However, while one model suggested that most of the rise in cases will be concentrated in the southern half of the United States, the other model identified the upper Midwest region as the future problem area.
"This problem is not just confined to the US," said Brikowski.
"This will also touch southern Europe, south-eastern Europe, and south-east Asia. And because in that last area treatment options are more limited, countries in that region will certainly experience a much more severe impact on health."
Kristina Penniston, a registered dietician and associate scientist in the Department of Urology at the University of Wisconsin School of Medicine and Public Health in Madison, called the new research "illuminating and provocative".
"It does seem entirely plausible that incidence (of kidney stones) will increase with global warming, primarily because one of the driving forces of incidence is hydration, and with global warming people will tend to be less well hydrated," she said.
"I'm also interested," Penniston added, "in how global warming will impact the diet of people, because there are also many nutritional factors related to kidney stones. And climate change affects the nutrient composition of the plants that we grow and the animals that we eat. For example, fruits and vegetables are inhibitors of stones. So the question then is, will people be eating less of that as temperatures rise because these things don't grow as abundantly? And will that then alter people's risk for stones? These are some of the important issues that this study raises."
Major Arctic ice shelf cracks, shedding 20 sq kilometres
Two chunks of ice together measuring almost 20 square kilometers (seven square miles) have broken off an Arctic ice shelf, the biggest breakup of Arctic ice in three years, Canadian officials announced.
Two floating islands of ice -- measuring four to five square kilometers (1.9 square miles) and 14 square kilometers (5.4 square miles) -- formed after the chunks broke from the Ward Hunt Ice Shelf off Ellesmere Island in the Canadian Arctic Archipelago, officials said.
"The first broke off sometime around July 22 and the second in the night of July 23 to 24," Luc Desjardins, a senior iceberg forecaster for Environment Canada's Ice Service, told AFP Tuesday.
Scientists confirmed the phenomenon in a fly-over of the first mass of ice and by analyzing satellite data.
It was the largest breakup of an ice shelf in the Arctic since the Ayles Ice Shelf broke off the Ellesmere Island coast in 2005 and formed a floating island of ice roughly the size of New York city's Manhattan, or about 66 square kilometers (25 square miles).
The August 2005 event emitted energy detected by Canadian seismology equipment 250 kilometers (155 miles) away, but it was not until scientists analyzed satellite data that they realized what had happened.
Five vast ice shelves surround the north side of Ellesmere Island in Canada's Nunavut Territory. Ward Hunt is considered the largest, with a surface area of 443 square kilometers (171 square miles).
The ice shelves, vast plateaus of thick ice floating on ocean but attached to land, began to form more than 4,000 years ago, Canadian scientists believe.
GM crop trials 'should be secret'
Senior researchers have called for the location of small open-air trials of GM crops to be kept secret.
The researchers say that vandalism of GM crop trials is holding back research in the area.
Current legislation requires the exact location of GM crop trials to be publicly available.
But according to those engaged in active research, that information is invariably used by anti-GM protesters to disrupt experiments.
The Department for Environment, Food and Rural Affairs (Defra), which licenses open air trials commented: "EU legislation says that we must disclose GM trial locations to the public.
"We are awating a European Court of Justice ruling, likely later this year, on a French legal case that should clarify how the EU law in this area can be interpreted by Member States."
Professor Howard Atkinson began a trial of GM potatoes earlier this year which he hoped would be resistant to disease.
The crops were pulled up three weeks after they were planted. Professor Atkinson is due to meet with the environment minister Phil Woolas in early September and will ask him to consider making changes to the current legislation.
"We should follow the same approach as that followed in Canada for very small scale trials of say 400 plants or so - where the risks are looked at by a panel but the location of those sites is not revealed," Professor Atkinson explained.
"The other possibility is to identify some national testing centre or centres where such trials could be run securely without the risk of zealots destroying them".
Security issues
Professor Atkinson said that open air trials were necessary to develop crops that could not only help farmers in the UK - but also help increase food production in Africa.
The disruption of trials, he said, has already led to companies moving away from the UK and academic research in the area has begun to decline.
"Academically, there has been a reduction in the attempt to do work of this type - they've found other problems to look at - but these are not generating practical benefits immediately and certainly not facing up to the big issue of food security in Africa," he said.
"As far as companies are concerned, they can do this sort of work elsewhere"
Jim Dunwell of Reading University and a member of ACRE, the Advisory Committee on Releases to the Environment, said there had been a sharp drop in the number of GM crop trials in Britain over the last few years with just one application for this year, down from about 20 to 30 per year in the late 1990s.
Local communities
Wayne Powell, who is the director of the National Institute of Agricultural Botany in Cambridge, was engaged in a trial of a crop that had the potential to benefit banana growers in Uganda. It was disrupted by protesters last year.
As a result, he said: "We now have 24-hour security, we have fences around materials."
However, anti-GM campaigners, such as Claire Oxborough of Friends of the Earth, believe that the trials should be stopped altogether.
She commented: "Friends of the Earth would have deep concerns about making them secret because of the potential risks that they pose.
"They are at the very early stages of development - we don't know the impact they'll have on the environment and on health and very often these trials are not set up to look at that."
She added: "What you don't want to do is get into a situation where in rural communities you have an air of distrust - rumours, speculation going on because no one knows what their neighbours might be growing.
"We need transparency - we need to know where these field trials are taking place so that farmers and the public can be adequately protected."
Scientists expose mystery behind northern lights
Scientists have exposed some of the mystery behind the northern lights. On Thursday, Nasa released findings that indicate magnetic explosions about one-third of the way to the moon cause the northern lights, or aurora borealis, to burst in spectacular shapes and colors, and dance across the sky.
The findings should help scientists better understand the more powerful but less common geomagnetic storms that can knock out satellites, harm astronauts in orbit and disrupt power and communications on Earth, scientists said.
A fleet of five small satellites, called Themis, observed the beginning of a geomagnetic storm in February, while ground observatories in Canada and Alaska recorded the brightening of the northern lights. The southern lights - aurora australis - also brightened and darted across the sky at the same time.
These auroral flare-ups occur every two or three days, on average.
A team led by University of California, Los Angeles, scientist Vassilis Angelopoulos confirmed that the observed storm about 80,000 miles from Earth was triggered by a phenomenon known as magnetic reconnection. Every so often, the Earth's magnetic field lines are stretched like rubber bands by solar energy, snap, are thrown back to Earth and reconnect, in effect creating a short circuit.
It's this stored-up energy that powers the northern and southern lights or, in other words, causes them to dance, according to Angelopoulos.
An opposing theory has these geomagnetic events occurring much closer to Earth, about one-sixth of the way to the moon. More Themis observations are needed to resolve the debate, said David Sibeck, NASA's project scientist.
"Finally, we have the right instruments in the right place at the right time, and it's allowed scientists to be able to make the necessary observations to settle this heated debate once and for all," said Nicola Fox, a Johns Hopkins University scientist who was not involved in the study.
At present, about 20 of these geomagnetic storms are being analyzed. Scientists hope to eventually learn, via this project, more about the bigger solar storms that occur about 10 times a year and can lead to far more expansive and prolonged northern and southern lights.
The five Themis spacecraft - a NASA acronym standing for Time History of Events and Macroscale Interations during Substorms - were launched aboard a single rocket last year.
Scientists to discuss climate risk posed by wetland destruction
Moves around the world to drain marshes and other wetlands to make space for farming could be hastening climate change, scientists gathering in Brazil from Monday will be hearing.
Around 700 researchers from around the world are to descend on the central western town of Cuiaba for a four-day conference to discuss ways to preserve wetlands, the UN University, a grouping of scholars, said in a statement.
They are concerned that evaporation from warmer global temperatures and man's destruction of wetlands are releasing massive amounts of carbon into the atmosphere, which could be increasing greenhouse gases.
Wetlands such as marshes, swamps, mangroves, peat bogs and river floodplains cover six percent of the Earth's land surface, and store up to 20 percent of terrestrial carbon in the form of slowly decaying organic matter, the statement said.
They are estimated to contain 771 billion tons of greenhouses gases -- carbon dioxide and methane -- an amount comparable to the carbon content already in the atmosphere.
According to the UN University, 60 percent of wetlands around the world have been destroyed in the past century, mainly to provide drainage for farming.
"Too often in the past, people have unwittingly considered wetlands to be problems in need of a solution. Yet wetlands are essential to the planet's health," said UN Under secretary-general Konrad Osterwalder, who is also rector of the UN University.
A German expert, professor Wolfgang Junk of the Max Planck Institute for Evolutionary Biology, added: "Wetlands act as sponges and their role as sources, reservoirs and regulators of water is largely under appreciated by many farmers and others who rely on steady water supplies."
The conference, co-organised with Brazil's Federal University of Mato Grosso in Cuiaba, will be looking at ways to protect and better manage wetlands, some of which extend over national borders.
Cuiaba itself is on the edge of the Pantanal, a remote and therefore relatively untouched wetland straddling Brazil, Bolivia and Paraguay.
The UN University is a community of researchers studying pressing global problems set up by the UN General Assembly. Its headquarters is in Japan.
Sleepiness can make you sound drunk
A lack of sleep alters the brain to such a degree that a person sounds drunk when they speak, according to a US study.
Bystanders might describe this type of speech as "tired-sounding" or "slurred," but experts studying the phenomenon say those descriptions aren't quite accurate.
The research, lead by Professor Suzanne Boyce from the University of Cincinnati was recently presented at the Acoustics08 meeting in Paris.
"Slurred speech is an extreme form of unclearly articulated speech," Boyce says.
"The differences we pick up are much less extreme, but they go in the same direction," says Boyce. "We'd call it 'faintly blurred,' rather than 'slurred,' speech."
Boyce and her team theorised that the differences between the speech of people lacking sleep and those who had a good night's rest would be comparable to the differences between conversational and "clear" speakers.
Over emphasising
"Clear" speech occurs when a person articulates or over-emphasises syllables, words and phrases - such as when addressing a formal gathering, talking to people who are hard of hearing or for whom the spoken language is not their native tongue.
A word like "police," for example, might sound more like "blees" in conversational speech, but like "poe-lees" in clear speech.
Boyce explains that "the process is largely subconscious," but when people articulate more "they add more acoustic information bits to the acoustic signal."
Computers can then detect these bits of information and note "landmarks," such as marking the puff of air released by the mouth when producing "t" or "k" sounds.
The researchers documented these changes and then applied the same analysis to recordings of test subjects who read sentences aloud and were asked to give driving directions approximately 10 hours since last sleep, then 34 and, finally, 58 hours.
The participants were allowed to eat and drink water, but not coffee or cola.
As expected, the sleep-deprived speakers gradually lost their ability to articulate, producing fewer detectible landmarks. Oddly enough, however, when such people hear themselves, they think they sound fine.
Improved listening skills
Boyce explained that "people lose awareness of how clearly they are speaking when they are tired."
In the future, the research may be used to train emergency phone line employees, communication professionals, and therapists who work with the hearing impaired.
Outside listeners, however, appear to have no trouble figuring out that the speaker missed some sleep.
"Listeners seem to clue in on other aspects, like sighs, long breaths and pauses in the recording, or even yawns, if they are audible," Boyce says, adding that if the person can see the speaker, they may also detect visual cues, "like posture, skin tone, eye gaze" and more.
Although not an optimal solution, scientists from Wake Forest University, North Carolina, have shown that the effects of sleep deprivation can be reversed when given a dose of the naturally occurring brain peptide orexin-A.
This chemical, normally secreted by brain neurons, regulates sleep. The brains of sleep-deprived people produce it, but often not enough to achieve full alertness.
"These findings are significant because of their potential applicability," says Wake Forest University Professor Samuel Deadwyler.
"This could benefit patients suffering from narcolepsy and other serious sleep disorders," he says, "but it also has applicability to shift workers, the military and many other occupations where sleep is often limited, yet cognitive demand remains high."
Nanotech regulation under the spotlight
A lack of scientific knowledge means Australian regulators could be unable to adequately protect humans and the environment from possible risks of nanotechnology, says a new report released by the Australian government today.
While the report says there is no need for major changes to regulatory regimes, critics say the findings suggest nanomaterials are essentially "unregulated" and should be taken off the market until we know how to assess their risk.
The science and industry minister Senator Kim Carr today released the report, commissioned by the Australian Office of Nanotechnology, into the adequacy of nanotechnology regulation.
The report, by the Centre for Regulatory Studies at Monash University, identifies six gaps in regulation.
The most significant, it says, is regulators may fail to distinguish between nano forms of products that differ in properties from their equivalent conventional forms.
The report says another problem is that regulation is sometimes triggered when materials are over a certain weight or volume.
But, it says, this "may not be meaningful" to regulating nanomaterials, because we don't understand enough about them, and there are "real difficulties" in even measuring their presence.
Lack of knowledge could also make it difficult for food authorities to prevent materials "likely to cause bodily harm" from being in contact with food, the report says.
"Current deficiencies in knowledge are such that we simply do not know the effects of some engineered [nanomaterials] on human health," it says.
And the report says scientific uncertainty also means that risk assessment protocols used by regulators designed to project humans or the environment may not be appropriate.
"Unregulated"
Adelaide-based toxicologist Dr Sam Bruschi says the report highlights a worrying lack of regulation of nanotechnology.
"At the moment there is no evidence of any regulation of nanomaterials at all," says Bruschi, who has acted as a peer-reviewer for the US Environmental Protection Agency and National Institute for Occupational Safety and Health on human health and environmental impacts of nanotechnology.
He says there is a lack of information to back regulation because not enough resources are being committed to nanotechnology safety studies and regulatory agencies seem to be assuming the technology is safe until proven otherwise.
"All that is required is the political will to address duty of care to the public," says Bruschi.
He says some studies suggest cause for concern, citing recent evidence that needle-like carbon nanotube fibres, already in commercial use, lead to lesions similar to those caused by asbestos.
"Some people dismissed that but I actually found that study to be a bit upsetting in the sense that it really did support the idea that carbon nanotubes were acting much like asbestos," Bruschi says.
He says where a nanomaterial is likely to be exposed to the public-at-large, it should not be on the market until it's been proven safe.
"Truck-sized" loopholes
Bruschi's views back calls by the Friends of the Earth Nanotechnology Project, for the science and industry minister to halt sales of nanoproducts until new laws are introduced to ensure their safety, nanoproducts are labelled, and the public is more involved.
The project's spokesperson Dr Rye Senjen says urgent action is required to close the "truck-sized" loopholes in regulation identified by the new report.
Senator Carr released a statement today saying the government is committed to "responsible management of nanotechnology" within existing regulatory frameworks and applying a precautionary approach.
"The novel properties that may provide benefits to society also raise concerns about how engineered nanomaterials may interact with human and other biological systems," the statement says.
'Cut not sink' emissions, says expert
We would be better off reducing our greenhouse emissions rather than trying to sink them into the sea using ocean fertilisation, suggests an Australian expert.
The comments come as the Australian Government considers its position on ocean fertilisation.
"If you asked me would I do this for CO2 mitigation [I'd say] not now," says Associate Professor Thomas Trull of the Antarctic Climate and Ecosystems Cooperative Research Centre in Hobart.
He says he does not think the benefits outweigh the risks of the technology at this point, and it should only be carefully researched as an option of last resort.
"Imagine if we started to realise that we were actually headed towards melting Greenland or we were going to flood Singapore, then we might say okay, I guess we'd better do this," says Trull.
"Personally I think we should avoid that by acting now on reducing our emissions rather than ... hoping that these backstop technologies will save us later."
Potential benefits
Ocean fertilisation involves adding nutrients such as iron or nitrogen to the sea to stimulate phytoplankton in the hope of sequestering carbon dioxide or fish stocks.
Trull says assuming the technology works and it is possible to verify sequestration, scientific models show the maximum amount of carbon that could be sunk into the ocean is less than 15% of the world's annual human generated greenhouse emissions.
"The total capacity is about 1 Gigatonne of carbon a year," he says.
Trull says the length of time carbon could be sequestered will vary between 6 months and 100 years.
Potential risks
According to Trull no studies have been specifically designed to look at the risks of ocean fertilisation but evidence suggests possible risks include upsetting the food web and creating dead zones in the ocean.
Risks could also include producing worse greenhouse gases like nitrous oxide and methane, blocking penetration of sunlight, trapping more heat or changing ocean circulation, he says.
He says using nitrogen is "more risky" than using iron, because it stays in the system for millennia, compared to iron, which sinks into sediments by natural processes over decades or a century at most.
"For me the overall return isn't that large for something you're taking a risk on," says Trull.
"It does seem to me it's not a huge ask to reduce CO2 production by 15% by reducing the spendthrift ways in which we use energy."
Environmental Assessment
International negotiations are yet to decide on how to control ocean fertilisation, but a number of commercial companies are already carrying out research and development on the technology.
One such company is the US-based Climos, which Trull says is planning to meet with him and other scientists in Hobart next week to discuss testing ocean fertilisation in the Southern Ocean.
The Southern Ocean is ripe for fertilisation with iron, which is the main nutrient limiting further production of biomass there, says Trull
He says Australian-based company Ocean Nourishment Company will be in Hobart the following week.
Trull says it's important for any regulation of ocean fertilisation to take a big picture view of its impacts.
"Many scientists, and I'm certainly one of them, feel that the real question now is what the long-term impact is if you do this in a persistent fashion," he says.
Any one particular project may not pose a problem but he says each approval sets a precedent for others but does not deal with the problem of cumulative impacts over the long term.
"It's a tragedy of the commons problem. We don't really have effective communal legislation to deal with that," he says.
Trull has contributed to a report that will soon be presented to the Australian government on the science and policy options relevant to ocean fertilisation.
Carbon Hoofprint
Cows Supplemented With RbST Reduce Agriculture's Environmental Impact
Milk goes green: Cows that receive recombinant Bovine Somatotropin (rbST) make more milk, all the while easing natural resource pressure and substantially reducing environmental impact, according to a Cornell University study.
Producing milk uses large quantities of land, energy and feed, but rbST -- the first biotech product used on American farms -- has been in agricultural use for nearly 15 years. Now it is found to reduce the carbon hoofprint by easing energy, land and nutritional inputs necessary to sustain milk production at levels sufficient to meet demand.
This research found that, compared to a non-supplemented population, giving rbST to one million cows would enable the same amount of milk to be produced using 157,000 fewer cows. The nutrient savings would be 491,000 metric tons of corn, 158,000 metric tons of soybeans, and total feedstuffs would be reduced by 2,300,000 metric tons. Producers could reduce cropland use by 219,000 hectares and reduce 2.3 million tons of soil erosion annually.
In 2007, there were 9.2 million cows in the United States. For every one million cows supplemented with rbST, the world would see an environmental saving of 824 million kilograms of carbon dioxide, 41 million kilograms of methane and 96,000 kilograms of nitrous oxide. For every one million cows supplemented with rbST, the reduction in the carbon footprint is equivalent to removing approximately 400,000 family cars from the road or planting 300 million trees.
"Supplementing cows with rbST on an industry-wide scale would improve sustainability and reduce the dairy industry's contribution to water acidification, algal growth, and global warming," says Judith L. Capper, Cornell post-doctoral researcher, and the lead author of the new paper in PNAS.
"Sustainability is important in agricultural production, with an emphasis placed upon meeting human food requirements while mitigating environmental impact," said Dale Bauman, an author of the study. "This study demonstrates that use of rbST markedly improves the efficiency of milk production, mitigates environmental impact including greenhouse gas emissions and reduces natural resource requirements such as fossil fuel, water and land use."
Invisible Waves Shape Continental Slope
A class of powerful, invisible waves hidden beneath the surface of the ocean can shape the underwater edges of continents and contribute to ocean mixing and climate, researchers from The University of Texas at Austin have found.
The scientists simulated ocean conditions in a laboratory aquarium and found that "internal waves" generate intense currents when traveling at the same angle as that of the continental slope. The continental slope is the region where the relatively shallow continental shelf slants down to meet the deep ocean floor.
They suspect that these intense currents, called boundary flows, lift sediments as the waves push into the continental slope, maintaining the angle of the slope through erosion. The action of the internal waves could also mix layers of colder and warmer water.
"Surprisingly little is known about how internal waves are generated and how they could lead to the mixing of the deep ocean, but it's very important," said physicist Hepeng Zhang. "Understanding ocean mixing is crucial for us to know whether changes in ocean circulation are the result of climate change or just variability."
Zhang said that as long as there is tidal motion that generates internal waves traveling along the continental slope, intense boundary flow will be produced.
"Twenty-four hours a day, seven days a week over a long geological time scale, and this will maintain the angle of the continental slope," he said.
He published his research with colleagues Harry Swinney and Benjamin King in Physical Review Letters.
Zhang studied internal waves using a simple saltwater aquarium equipped with a sloping bottom simulating the continental slope. Water in the tank increased in density from top to bottom, just as water is denser on the ocean floor. Thousands of very small particles, 10 microns or smaller, were suspended in the water.
As Zhang generated waves in the tank, he took photographs and video footage of the particles and then analyzed the particles' direction of flow and velocity.
Particle motion revealed intense boundary flows when the angle of the bottom matched the angle at which internal waves can travel.
Oceanic continental slopes could theoretically reach angles of 15 to 20 degrees as sediments continually pour down from the continents, but Zhang said that the internal waves are limiting the angle to around three degrees, the average angle of continental slopes.
The internal waves could also play a role in larger ocean currents by bringing cold water up from the deep ocean to the surface at the equator.
Ocean currents form closed loops, with warm surface water, like the Gulf Stream, moving toward the poles and cold water circulating back toward the equator at depth. The warm surface water heated at the equator is largely driven to the poles by wind. At the poles, this water is cooled by the cold air and mixes with cold water from melting glaciers and ice. Although fresh water is less dense than sea water, the cooling effect wins out and the density increases until the water sinks.
Zhang found that the internal waves could help bring this cold water closer to the surface when the boundary flow pushes heavier, colder water over warmer lighter water on the continental slope. This results in the internal wave breaking and mixing on the slope, just as a surface wave breaks on the shore.
"How exactly this will contribute to ocean circulation, I really don't know," said Zhang. "But it is definitely a step we have to understand before we can understand global ocean circulation."
Fortified Cassava Could Provide A Day's Nutrition In A Single Meal
Scientists have determined how to fortify the cassava plant, a staple root crop in many developing countries, with enough vitamins, minerals and protein to provide the poor and malnourished with a day's worth of nutrition in a single meal.
The researchers have further engineered the cassava plant so it can resist the crop's most damaging viral threats and are refining methods to reduce cyanogens, substances that yield poisonous cyanide if they are not properly removed from the food before consumption. The reduction of cyanogens also can shorten the time it takes to process the plant into food, which typically requires three to six days to complete.
Studies also are under way to extend the plant's shelf life so it can be stored or shipped.
The international team of scientists hopes to translate the greenhouse research into a product that can be field tested in at least two African nations by 2010. Funded by more than $12.1 million in grants from the Bill & Melinda Gates Foundation, the group of researchers is led by Richard Sayre, a professor of plant cellular and molecular biology at Ohio State University.
Sayre presented an update on the BioCassava Plus project June 30 at the American Society of Plant Biologists meeting in Mérida, Mexico.
"This is the most ambitious plant genetic engineering project ever attempted," Sayre said. "Some biofortification strategies have the objective of providing only a third of the daily adult nutrition requirements since consumers typically get the rest of their nutritional requirements from other foods in their diet. But global food prices have recently gone sky high, meaning that many of the poorest people are now eating just one meal a day, primarily their staple food.
"So what we're working on has become even more important in the last year than it was when we started, not just in regions where people are malnourished, but across developing countries where food has gotten so expensive that people can't afford the diverse diet that they're used to."
Cassava (Manihot esculenta) is the primary source of calories for an estimated 800 million people worldwide, including 250 million people in sub-Saharan Africa, the current focus of the Gates-funded project. But the plentiful crop has several drawbacks. It is composed almost entirely of carbohydrates so it does not provide complete nutrition.
"So what we're working on has become even more important in the last year than it was when we started, not just in regions where people are malnourished, but across developing countries where food has gotten so expensive that people can't afford the diverse diet that they're used to."
The roots can be banked in the ground for up to three years, providing food security, but the plant must undergo time-consuming processing immediately after harvest to remove compounds that generate cyanide. Unprocessed roots also deteriorate within 48 hours after harvest, limiting the food's shelf life. And a plant disease caused by the geminivirus reduces yields by 30 percent to 50 percent in many areas in sub-Saharan Africa, a major blow to farm productivity.
Sayre and colleagues from multiple institutions set out to tackle virtually all of cassava's problems to make the plant more nutritious and to increase the crop's revenue-producing potential for farmers.
Sayre reported that the research team has been able to address each of the plant's deficiencies in individual transgenic plants. The next step will be to combine some or all of the bioengineered traits into a single, farmer-preferred cultivar, with the goal of eventually developing cassava varieties that carry all of the improvements developed by the researchers.
"We've begun field trials in Puerto Rico to make sure the plants perform as well outside as they do in greenhouses, and we hope to start field trials in the target countries of Nigeria and Kenya by 2009," Sayre said.
The labs in the project have used a variety of techniques to improve on the model cassava plant used for the research. They used genes that facilitate mineral transport to produce a cassava root that accumulates more iron and zinc from the soil. To fortify the plants with a form of vitamin E and beta-carotene (also called pro-vitamin A because it converts to vitamin A in the body), the scientists introduced genes into the plant that increase terpenoid and carotenoid production, the precursors for pro-vitamin A and vitamin E. They achieved a 30-fold increase in pro-vitamin A, which is critical for human vision, bone and skin health, metabolism and immune function.
Adding protein to the cassava plant has posed a challenge, Sayre said. The scientists discovered that most of the nitrogen required to make the amino acids used for protein synthesis in roots is derived from the cyanogens that also cause cyanide toxicity. So their strategy for increasing protein levels in roots focuses on accelerating the conversion of cyanide-containing compounds into protein rather than completely eliminating cyanogen production, which would hinder the efforts to increase protein production, Sayre explained. To further address the cyanide problem, the scientists have also developed a way to accelerate the processing methods required to remove cyanide -- a days-long combination of peeling, soaking and drying the roots before they are eaten.
To strengthen the cassava plant's resistance to viruses, the scientists introduced a protein and small interfering RNA molecules that interfere with the viruses' ability to reproduce.
Prolonging cassava's shelf life has involved the development of a hybrid species that crosses two related plants native to Texas and Brazil. The strategy, still in development, will combine the properties of these plants and additional genes that function as antioxidants, slowing the rotting process that has been traced to the production of free radicals that damage and kill cells in newly harvested cassava roots.
The first cassava product the team plans to develop for investigations in the field will likely include the virus resistance, elevated protein, elevated beta-carotene (pro-vitamin A) and elevated minerals (iron and zinc), Sayre said.
"These traits have been working the best in the greenhouse, and the virus resistance is critical to success in the field," he said. "The thinking behind starting with these four traits is driven by science and by the impact they can have."
The BioCassava Plus project was launched with a $7.5 million grant from the Gates Foundation and recently received an additional $4.6 million in supplemental funding from the foundation to accelerate the application of this research in Africa by African scientists. The supplemental funding will support the training of African scientists so they can produce the transgenic plants in African institutions for use on African farms.
"It will not only be an improved staple crop eaten as a main source of nutrition, but we're also looking at the transformation of cassava from a staple crop to an income-generating crop," Sayre said. "That lifts people out of poverty, allows families to send kids to school and build infrastructure in their villages, so this is an important way to cross cultural barriers. There are many different cultures and languages in Africa, but higher crop yield, productivity, longer shelf life and making money are things that everyone understands."
The BioCassava Plus research team includes Claude Fauquet, Nigel Taylor, Dan Shachtman, Ed Cahoon and Paul Anderson of the Donald Danforth Plant Science Center in St. Louis; Willi Gruissem and Peng Zhang of the Swiss Federal Institute of Technology in Zurich; John Beeching of the University of Bath in England; John Fellman of Washington State University; Martin Fregene and Hernan Ceballos of the International Center for Tropical Agriculture in Colombia; Ivan Ingelbrecht, Alfred Dixon and Bussie Maziya-Dixon of IITA-Nigeria (an African research organization); Caroline Herron of IITA-Kenya; Simon Gichuki of the Kenya Agricultural Research Institute; Ada Mbanaso of the National Root Crops Research Institute in Nigeria; Dimuth Siritunga of the University of Puerto Rico; Mark Manary of Washington University; and independent consultant Jeff Stein. Mary Ann Abiado and Kristen Mosier of Ohio State provide administrative oversight.
In 'Novel Playground,' Metals Self-assemble Into Porous Nanostructures
For 5,000 years or so, the only way to shape metal has been to "heat and beat." Even in modern nanotechnology, working with metals involves carving with electron beams or etching with acid.
"The polymer community has tried to do this for 20 years," said Ulrich Wiesner, Cornell professor of materials science and engineering, who, with colleagues, reports on the new method in the June 27 issue of the journal Science. "But metals have a tendency to cluster into uncontrolled structures. The new thing we have added is the ligand, which creates high solubility in an organic solvent and allows the particles to flow even at high density."Another key factor, he added, is to make the layer of ligand surrounding each particle relatively thin, so that the volume of metal in the final structure is large enough to hold its shape when the organic materials are removed."This is exciting," Wiesner said. "It opens a completely novel playground because no one has been able to structure metals in bulk ways. In principle, if you can do it with one metal you can do it with mixtures of metals."
Wiesner and two Cornell colleagues, Francis DiSalvo, the J.A. Newman Professor of Chemistry and Chemical Biology, and Sol Gruner, the John L. Wetherill Professor of Physics, as well as other researchers, report in Science how they used the new method to create a platinum structure with uniform hexagonal pores on the order of 10 nm across (a nanometer is the width of three silicon atoms). Platinum is, so far, the best available catalyst for fuel cells, and a porous structure allows fuel to flow through and react over a larger surface area.The researchers began by mixing a solution of ligand-coated platinum nanoparticles with a block co-polymer. The solution of nanoparticles combines with just one of the two polymers. The two polymers assemble into a structure that alternates between small regions of one and the other, in this case producing clusters of metal nanoparticles suspended in one polymer and arranged around the outside of hexagonal shapes of the other polymer. Many other patterns are possible, depending on the choice of polymers.
The material is then annealed in the absence of air, turning the polymers into a carbon scaffold that continues to support the shape into which the metal particles have been formed. Wiesner and colleagues have previously used the carbon scaffold approach to create porous nanostructures of metal oxides.The final step is to heat the material to a higher temperature in air to oxidize the ligands and burn away the carbon. Metal nanoparticles have a very low melting point at their surface, so the particles sinter together into a solid metal structure. The researchers have made fairly large chunks of porous platinum this way, up to at least a half-centimeter across.In addition to making porous materials, the researchers said, the technique could be used to create finely structured surfaces, the key to the new field of plasmonics, in which waves of electrons move across the surface of a conductor with the information-carrying capacity of fiber optics, but in spaces small enough to fit on a chip.
Ancient Oak Trees Help Reduce Global Warming
The battle to reduce carbon emissions is at the heart of many eco-friendly efforts, and researchers from the University of Missouri have discovered that nature has been lending a hand. Researchers at the Missouri Tree Ring Laboratory in the Department of Forestry discovered that trees submerged in freshwater aquatic systems store carbon for thousands of years, a significantly longer period of time than trees that fall in a forest, thus keeping carbon out of the atmosphere.
While a tree is alive, it has a high ability to store carbon, thus keeping it out of the atmosphere. However, as it begins to decay, a tree’s carbon is released back into the atmosphere. Discovering that certain conditions slow this process reveals the importance of proper tree disposal as well as the benefits of riparian forests.“Carbon plays a huge role in climate change and information about where it goes will be very important someday soon,” said Michael C. Stambaugh, research associate in the MU Department of Forestry. “The goal is to increase our knowledge of the carbon cycle, particularly its exchange between the biosphere (plants) and atmosphere. We need to know where it goes and for how long in order to know how to offset its effects.”
This could be a valuable find for landowners. Although it is not yet common in North America, emissions trading has been gaining popularity in parts of Europe. Also known as cap and trade, emissions trading works to reduce pollution by setting a limit on the amount of pollutants an organization can emit into the air. If they exceed that number, the group is required to obtain carbon credits. One carbon credit equals one metric ton of carbon-dioxide or other equivalent greenhouse gases.Carbon credits can be purchased in a variety of ways. Such as: planting new trees or harvesting old wood that has stored carbon; collecting methane from landfills; or purchasing credits from other companies who have a carbon surplus by staying below their emission requirements.
This week, the California Air Resources Board announced the consideration of a large plan to fight global warming. The recommendations include reducing emissions, in part by requiring major polluters to trade carbon credits.“Farmers can sell the carbon they have stored in their trees through a carbon credit stock market,” Guyette said. “Companies that emit excess of carbon would be able to buy carbon credits to offset their pollution.”
What It's Like To Be A Bat
Sonar Does More Than Locate Objects; It Cues Memory And Assists Flight
Not many people think about what it's like to be a bat, but for those who do, it's enlightening and potentially groundbreaking for understanding aspects of the human brain and nervous system.
"For decades it's been recognized that a bat's voice produces sounds that give the bat information about the location of objects," says Moss. "We're now recognizing that every time a bat produces a sound there are changes in brain activity that may be important for scene analysis, sensorimotor control and spatial memory and navigation." The research could help neurobiologists understand mechanisms in the human brain and ultimately benefit human health, but that may not happen for some time as more research is needed.Moss and her colleague, Nachum Ulanovsky from the Weizmann Institute of Science in Israel, reviewed more than 100 studies and determined the brief calls emitted through a bat's mouth or nostrils and their returning echoes play a pivotal role in motor control and have other behavioral implications.
The vocalizations tell the bat the horizontal and vertical positions of its prey from differences in the arrival time, intensity, and variety of echoes it receives. It estimates target range from the time delay between the outgoing vocalization and returning echo. It also uses its sonar system to assess the size of a target. Finally, when zeroed in, it swoops down on its prey. Researchers are able to draw correlations between how bats and humans process information to perform functions. Both are mammals having the same basic brain organization, which leads to obvious comparisons. According to Moss, bats engage in vocal-motor behaviors to generate signals to probe the environment, while some blind humans produce tongue clicks to generate sounds for echolocation.
Both bats and humans engage in so-called "motor behaviors" that shape their perceptions of the world. A bat turns its head, moves its ears, and changes its flight path in response to echo information from the environment. A human moves his eyes or turns his head to augment his perception of auditory and visual signals. "All of these motor behaviors influence the animal's perception and representation of the environment," says Moss. "But of interest to us is the idea that these vocal-motor behaviors contribute to environmental perception, memory, and spatial planning far beyond the processing of sound." "It may be that some of the information we learn from the bat gives us a window into understanding mechanisms of the human brain," says Moss. "But those outcomes are a little bit down the road."
Super-sensitive Explosives Detector Demonstrated
Using a laser and a device that converts reflected light into sound, researchers at the Department of Energy's Oak Ridge National Laboratory can detect explosives at distances exceeding 20 yards.
The method is a variation of photoacoustic spectroscopy but overcomes a number of problems associated with this technique originally demonstrated by Alexander Graham Bell in the late 1880s. Most notably, ORNL researchers are able to probe and identify materials in open air instead of having to introduce a pressurized chamber, which renders photoacoustic spectroscopy virtually useless for security and military applications.
ORNL's technique, detailed in Applied Physics Letters 92, involves illuminating the target sample with an eye-safe pulsed light source and allowing the scattered light to be detected by a quartz crystal tuning fork. "We match the pulse frequency of the illuminating light with the mechanical resonant frequency of the quartz crystal tuning fork, generating acoustic waves at the tuning fork's air-surface interface," said Charles Van Neste of ORNL's Biosciences Division. "This produces pressures that drive the tuning fork into resonance." The amplitude of this vibration is proportional to the intensity of the scattered light beam falling on the tuning fork, which because of the nature of quartz creates a piezoelectric voltage. Van Neste and co-authors Larry Senesac and Thomas Thundat note that other advantages of quartz tuning fork resonators include compact size, low cost, commercial availability and the ability to operate in field conditions environments.
For their experiments, researchers used tributyl phosphate and three explosives - cyclotrimethylenetrinitromine, trinitrotoluene, commonly known as TNT, and pentaerythritol tetranitrate. They were able to detect trace residues with lasers 100 times less powerful than those of competing technologies. While the researchers have been able to detect explosives at 20 meters, using larger collection mirrors and stronger illumination sources, they believe they can achieve detection at distances approaching 100 meters. This research was funded by DOE's Office of Nonproliferation Research and Development and the Office of Naval Research. UT-Battelle manages Oak Ridge National Laboratory for the Department of Energy.
On The Boil
New Nano Technique Significantly Boosts Boiling Efficiency
Whoever penned the old adage “a watched pot never boils” surely never tried to heat up water in a pot lined with copper nanorods.
“Like so many other nanotechnology and nanomaterials breakthroughs, our discovery was completely unexpected,” said Nikhil A. Koratkar, associate professor in the Department of Mechanical, Aerospace, and Nuclear Engineering at Rensselaer, who led the project. “The increased boiling efficiency seems to be the result of an interesting interplay between the nanoscale and microscale surfaces of the treated metal. The potential applications for this discovery are vast and exciting, and we’re eager to continue our investigations into this phenomenon.”
Bringing water to a boil, and the related phase change that transforms the liquid into vapor, requires an interface between the water and air. In the example of a pot of water, two such interfaces exist: at the top where the water meets air, and at the bottom where the water meets tiny pockets of air trapped in the microscale texture and imperfections on the surface of the pot. Even though most of the water inside of the pot has reached 100 degrees Celsius and is at boiling temperature, it cannot boil because it is surrounded by other water molecules and there is no interface — i.e., no air — present to facilitate a phase change.
Bubbles are typically formed when air is trapped inside a microscale cavity on the metal surface of a vessel, and vapor pressure forces the bubble to the top of the vessel. As this bubble nucleation takes place, water floods the microscale cavity, which in turn prevents any further nucleation from occurring at that specific site. Koratkar and his team found that by depositing a layer of copper nanorods on the surface of a copper vessel, the nanoscale pockets of air trapped within the forest of nanorods “feed” nanobubbles into the microscale cavities of the vessel surface and help to prevent them from getting flooded with water. This synergistic coupling effect promotes robust boiling and stable bubble nucleation, with large numbers of tiny, frequently occurring bubbles.
“By themselves, the nanoscale and microscale textures are not able to facilitate good boiling, as the nanoscale pockets are simply too small and the microscale cavities are quickly flooded by water and therefore single-use,” Koratkar said. “But working together, the multiscale effect allows for significantly improved boiling. We observed a 30-fold increase in active bubble nucleation site density — a fancy term for the number of bubbles created — on the surface treated with copper nanotubes, over the nontreated surface.” Boiling is ultimately a vehicle for heat transfer, in that it moves energy from a heat source to the bottom of a vessel and into the contained liquid, which then boils, and turns into vapor that eventually releases the heat into the atmosphere. This new discovery allows this process to become significantly more efficient, which could translate into considerable efficiency gains and cost savings if incorporated into a wide range of industrial equipment that relies on boiling to create heat or steam.
“If you can boil water using 30 times less energy, that’s 30 times less energy you have to pay for,” he said. The team’s discovery could also revolutionize the process of cooling computer chips. As the physical size of chips has shrunk significantly over the past two decades, it has become increasingly critical to develop ways to cool hot spots and transfer lingering heat away from the chip. This challenge has grown more prevalent in recent years, and threatens to bottleneck the semiconductor industry’s ability to develop smaller and more powerful chips. Boiling is a potential heat transfer technique that can be used to cool chips, Koratkar said, so depositing copper nanorods onto the copper interconnects of chips could lead to new innovations in heat transfer and dissipation for semiconductors. “Since computer interconnects are already made of copper, it should be easy and inexpensive to treat those components with a layer of copper nanorods,” Koratkar said, noting that his group plans to further pursue this possibility.
Along with Koratkar, co-authors of the paper include Rensselaer MANE Associate Professor Yoav Peles; Rensselaer mechanical engineering graduate student Zuankai Wang; Rensselaer Center for Integrated Electronics Research Associate Pei-I Wang; University of Colorado at Boulder Chancellor and former Rensselaer Provost G.P. “Bud” Peterson; and UC-Boulder Assistant Research Professor Chen Li. The research was funded by the National Science Foundation
Morbid Thoughts Whet The Appetite
Can watching TV news or crime shows trigger overeating? According to new research in the Journal of Consumer Research, people who are thinking about their own deaths want to consume more.
"People want to consumer more of all kinds of foods, both healthy and unhealthy, when thinking about the idea that they will die some day," write the authors. The researchers found people with low self-esteem, in particular, tend to over-consume after death-related thoughts. Mandel and Smeesters explain the effect using a theory called "escape from self-awareness." "When people are reminded of their inevitable mortality, they may start to feel uncomfortable about what they have done with their lives and whether they have made a significant mark on the universe. This is a state called 'heightened self-awareness.' One way to deal with such an uncomfortable state is to escape from it, by either overeating or overspending," they write.
The study also revealed that placing a mirror in front of the participants reduced the desire to over-consume.
"Consumers, especially those with a lower self-esteem, might be more susceptible to over-consumption when faced with images of death during the news or their favorite crime-scene investigation shows," the authors conclude.
Fire Under Arctic Ice
Volcanoes Have Been Blowing Their Tops In The Deep Ocean
A research team led by the Woods Hole Oceanographic Institution (WHOI) has uncovered evidence of explosive volcanic eruptions deep beneath the ice-covered surface of the Arctic Ocean. Such violent eruptions of splintered, fragmented rock--known as pyroclastic deposits -- were not thought possible at great ocean depths because of the intense weight and pressure of water and because of the composition of seafloor magma and rock.
Researchers found jagged, glassy rock fragments spread out over a 10 square kilometer (4 square mile) area around a series of small volcanic craters about 4,000 meters (2.5 miles) below the sea surface. The volcanoes lie along the Gakkel Ridge, a remote and mostly unexplored section of the mid-ocean ridge system that runs through the Arctic Ocean. "These are the first pyroclastic deposits we've ever found in such deep water, at oppressive pressures that inhibit the formation of steam, and many people thought this was not possible," said WHOI geophysicist Rob Reves-Sohn, lead author and chief scientist for the Arctic Gakkel Vents Expedition (AGAVE) of July 2007. "This means that a tremendous blast of CO2 was released into the water column during the explosive eruption." The paper, which was co-authored by 22 investigators from nine institutions in four countries, was published in the June 26 issue of the journal Nature.
Seafloor volcanoes usually emit lobes and sheets of lava during an eruption, rather than explosive plumes of gas, steam, and rock that are ejected from land-based volcanoes. Because of the hydrostatic pressure of seawater, ocean eruptions are more likely to resemble those of Kilauea than Mount Saint Helens or Mount Pinatubo. Making just the third expedition ever launched to the Gakkel Ridge--and the first to visually examine the seafloor--researchers used a combination of survey instruments, cameras, and a seafloor sampling platform to collect samples of rock and sediment, as well as dozens of hours of high-definition video. They saw rough shards and bits of basalt blanketing the seafloor and spread out in all directions from the volcanic craters they discovered and named Loke, Oden, and Thor.
They also found deposits on top of relatively new lavas and high-standing features--such as Duque's Hill and Jessica's Hill--indications that the rock debris had fallen or precipitated out of the water, rather than being moved as part of a lava flow that erupted from the volcanoes.
Closer analysis has shown that the some of the tiny fragments are angular bits of quenched glass known to volcanologists as limu o Pele, or "Pele's seaweed." These fragments are formed when lava is stretched thin around expanding gas bubbles during an explosion. Reves-Sohn and colleagues also found larger blocks of rock--known as talus--that could have been ejected by explosive blasts from the seafloor.
Much of Earth's surface is made up of oceanic crust formed by volcanism along seafloor mid-ocean ridges. These volcanic processes are tied to the rising of magma from Earth's mantle and the spreading of Earth's tectonic plates. Submerged under several kilometers of cold water, the volcanism of mid-ocean ridges tends to be relatively subdued compared to land-based eruptions. To date, there have been scattered signs of pyroclastic volcanism in the sea, mostly in shallower water depths. Samples of sediment and rock collected on other expeditions have hinted at the possibilities at depths down to 3,000 meters, but the likelihood of explosive eruptions at greater depths seemed slim.
One reason is the tremendous pressure exerted by the weight of seawater, known as hydrostatic pressure. More importantly, it is very difficult to build up the amount of steam and carbon dioxide gas in the magma that would be required to explode a mass of rock up into the water column. (Far less energy is needed to do so in air.) In fact, the buildup of CO2 in magma in the sea crust would have to be ten times higher than anyone has ever observed in seafloor samples.
The findings from the Gakkel Ridge expedition appear to show that deep-sea pyroclastic eruptions can and do happen. "The circulation and plumbing of the Gakkel Ridge might be different," said Reves-Sohn. "There must be a lot more volatiles in the system than we thought." The research team hypothesizes that excess gas may be building up like foam or froth near the ceiling of the magma chambers beneath the crust, waiting to pop like champagne beneath a cork.
"Are pyroclastic eruptions more common than we thought, or is there something special about the conditions along the Gakkel Ridge?" said Reves-Sohn. "That is our next question."
Support for the Arctic Gakkel Vents Expedition and for vehicle development was provided by the National Science Foundation's Office of Polar Programs; the NSF Division of Ocean Sciences; the Gordon Center for Subsurface Sensing and Imaging Systems, an NSF Engineering Research Center; the NASA Astrobiology Program; and the WHOI Deep Ocean Exploration Institute.
NASA
Open science promised for Phoenix
The US space agency (Nasa) has quashed any idea that it is hiding information related to discoveries made on Mars.
Nasa has acknowledged that its Phoenix probe has seen an unexpected compound - perchlorate - in the Martian soil but says the analysis is incomplete.
Scientists said they had not discussed the issue publicly earlier because they were unsure of the data's significance.
They said the discovery - if confirmed - was fascinating but made "life on Mars" neither more nor less likely.
Peter Smith, the Phoenix principal investigator from University of Arizona, stressed that his team would be completely open about its investigations.
"Our policy from the beginning has been to show all our pictures as they come in and to try to involve the world, along with us, in exploring Mars for a habitable zone," he told reporters.
"We really feel it's time to let everybody know what we're finding and get that window into our project."
The fuss had kicked off over the weekend when rumours swept the web that major findings from Phoenix were being held back.
The source of this internet storm was an Aviation Week article that claimed the "White House has been alerted by Nasa about plans to make an announcement soon on major new Phoenix lander discoveries concerning the 'potential for life' on Mars".
The respected magazine further claimed that scientists working on one of the Phoenix instrument suites had even been kept out of a press conference last week to avoid the risk they might have to answer questions on the subject.
That subject - Nasa has now confirmed - is the detection in the Martian soil of a strong perchlorate signal.
Water story
Perchlorate (a compound containing chlorine and oxygen) is a potentially oxidising substance often seen in arid soils on Earth, such as in the Atacama desert in Chile.
Although the super-dry Atacama was often regarded as being hostile to life, the same assumption should not be made about the presence of perchlorates, the Phoenix team said.
"[On Earth] there are a large number of plants that concentrate perchlorate and grow in perchlorate at certain levels; there are a variety of species of bacteria that utilise perchlorate as a substrate in their metabolism," explained mission scientist Sam Kounaves, from Tufts University.
The apparent perchlorate signal was seen by the probe's Microscopy, Electrochemistry, and Conductivity Analyzer (MECA), but Nasa stresses that complementary analysis is needed to confirm the data and finesse the details.
On Earth, perchlorates are created in the atmosphere by the interaction of aerosols or dust particles in sunlight, and are dry-deposited onto the surface.
In a desert setting, they stay at the surface; but in wet regions, they will quickly move through the soil.
"Perchlorates will tell us quite a bit about the history of water, not just at the Phoenix landing site but in other parts of Mars as we continue our exploration," explained Richard Quinn, a Phoenix researcher from Nasa's Ames centre.
"Currently, we've seen the perchlorates at the surface and a future line of research will be to look at where else they are on the planet and whether or not water and salt mobility was involved in that transport."
Phoenix scientists have more time to work up their findings. The US space agency recently agreed to add another five weeks to the original 90 days of the prime mission.
Nasa probe finds per chlorate in Mars soil sample
The Phoenix lander's analysis of recent soil samples taken on Mars has found possible traces of perchlorate, a highly oxidizing substance detrimental to life, Nasa said Monday.
Two separate soil samples were analyzed within the last month by two onboard Phoenix instruments, "suggesting one of the soil constituents may be perchlorate," Nasa said in a statement stressing the preliminary quality of the tests.
"We are committed to following a rigorous scientific process. While we have not completed our process on these soil samples, we have very interesting intermediate results," said Peter Smith, Phoenix's principal investigator at the University of Arizona, Tucson.
"Initial ... analyses suggested Earth-like soil. Further analysis has revealed un-Earthlike aspects of the soil chemistry," he added.
Investigators are working to eliminate any possibility the perchlorate readings in the Martian soil samples were influenced by terrestrial sources coming from the Phoenix spacecraft itself, the National Aeronautics and Space Administration said.
The soil samples analyzed on Sunday containing a white ice-like substance that when melted turned out to be water -- confirming initial suspicions in June -- did not contain perchlorate, it added.
The soil samples were analyzed by the Wet Chemistry Lab of the spacecraft's Microscopy, Electrochemistry, and Conductivity Analyzer, or MECA, Nasa said.
The Phoenix team is also waiting for complementary results from the Thermal and Evolved-Gas Analyzer, or TEGA, which also is capable of detecting perchlorate, it added. TEGA sniffed the vapor from the ice sample confirming it was indeed water.
Nasa said it will hold a press conference Tuesday to discuss the recent finding.
The Phoenix lander started digging trenches into Martian soil after touching down near the planet's north pole on May 25, revealing a white substance that scientists said was ice in June.
Although important nutrients including sodium, potassium and magnesium had been discovered on Mars, no organic materials had been found so far, the Phoenix team said.
Phoenix tries again for ice test
Nasa's Phoenix spacecraft will try a new way of getting icy Martian soil into its onboard oven for testing, after it ran into problems last week.
The soil has proven to be very sticky, hampering attempts to carry out tests.
On its previous attempt, most of the soil sample collected by Phoenix's robotic arm got stuck in the scoop and would not fall into the oven.
Controllers will now try a different strategy which involves less drilling and more shaking of the scoop.
Phoenix touched down successfully on Mars' northern plains on 25 May (GMT).
"We are going to modify the process we ran on Sol 60 to acquire another icy sample and attempt to deliver it to TEGA [the Thermal and Evolved-Gas Analyzer instrument]", said Barry Goldstein, the mission's project manager.
Mr Goldstein, from Nasa's Jet Propulsion Laboratory in California, added: "We will repeat what we did successfully with small modifications to adjust for what we learned."
The TEGA ovens will bake and sniff the soil to assess its volatile chemical ingredients, such as water. This could give scientists clues to whether Mars was ever capable of supporting life.
On 26 July, Phoenix successfully obtained a sample of ice and soil by drilling 16 holes into the work trench informally named "Snow White" with the motorised "rasp" on the end of its robotic arm.
It then picked up the sample with its scoop, but most of the sticky Martian soil adhered to the scoop even after it was tipped and the rasp activated to help sprinkle soil into the oven for baking and analysis by TEGA.
The revised plan involves cutting the amount of time spent using the rasp, to avoid heating the sample, and shaking the scoop more when delivering it to the oven.
Images received by mission control on Sunday morning showed the soil collected during the previous attempt has now fallen out of the scoop.