Showing posts with label SCIENCE. Show all posts
Showing posts with label SCIENCE. Show all posts

Monday, February 20, 2012

Lab-grown meat is first step to artificial hamburger



Lab grown meatThe first strips of muscle have been grown in a project to develop a new way to produce meat


Dutch scientists have used stem cells to create strips of muscle tissue with the aim of producing the first lab-grown hamburger later this year.
The aim of the research is to develop a more efficient way of producing meat than rearing animals.
At a major science meeting in Canada, Prof Mark Post said synthetic meat could reduce the environmental footprint of meat by up to 60%.
"We would gain a tremendous amount in terms of resources," he said.
Professor Post's group at Maastricht University in the Netherlands has grown small pieces of muscle about 2cm long, 1cm wide and about a mm thick.
They are off-white and resemble strips of calamari in appearance. These strips will be mixed with blood and artificially grown fat to produce a hamburger by the autumn.
The cost of producing the hamburger will be £200,000 but Professor Post says that once the principle has been demonstrated, production techniques will be improved and costs will come down.
At a news conference, Prof Post said he was even planning to ask celebrity chef Heston Blumenthal to cook it.

Start Quote

In the beginning it will taste bland. I think we will need to work on the flavour”
Prof Mark PostUniversity of Maastricht
"The reason we are doing this is not to show a viable product but to show that in reality we can do this," he told BBC News.
"From then on, we need to spend a whole lot of work and money to make the process efficient and then cost effective."
So why use such high tech methods to produce meat when livestock production methods have done the job effectively for thousands of years?
It is because most food scientists believe that current methods of food production are unsustainable.
Some estimate that food production will have to double within the next 50 years to meet the requirements of a growing population. During this period, climate change, water shortages and greater urbanisation will make it more difficult to produce food.
Prof Sean Smukler from the University of British Columbia said keeping pace with demand for meat from Asia and Africa will be particularly hard as demand from these regions will shoot up as living standards rise. He thinks that lab grown meat could be a good solution.
ButcherDemand for meat will increase at a time when it will be harder than ever for farmers to boost production
"It will help reduce land pressures," he told BBC News. "Anything that stops more wild land being converted to agricultural land is a good thing. We're already reaching a critical point in availability of arable land," he said.
Lab-grown meat could eventually become more efficient than producing meat the old fashioned way, according to Prof Post. Currently, 100g of vegetable protein has to be fed to pigs or cows to produce 15g of animal protein, an efficiency of 15%. He believes that synthetic meat could be produced with an equivalent energy efficiency of 50%.
So what is the synthetic burger likely to taste like?
"In the beginning it will taste bland," says Prof Post. "I think we will need to work on the flavour separately by trying to figure out which components of the meat actually produce the taste and analyse what the composition of the strip is and whether we can change that."
Prof Post also said that if the technology took off, it would reduce the number of animals that were factory farmed and slaughtered.
The BBC's Pallab Ghosh reports from Duggie's Dogs hot dog restaurant in Downtown Vancouver
But David Steele, who is president of Earthsave Canada, said that the same benefits could be achieved if people ate less meat.
"While I do think that there are definite environmental and animal welfare advantages of this high-tech approach over factory farming, especially, it is pretty clear to me that plant-based alternatives... have substantial environmental and probably animal welfare advantages over synthetic meat," he said.
Dr Steele, who is also a molecular biologist, said he was also concerned that unhealthily high levels of antibiotics and antifungal chemicals would be needed to stop the synthetic meat from rotting.

Digital tools 'to save languages'



Tuvan iPhone appThere's an app for everything - even an endangered language like Tuvan


Facebook, YouTube and even texting will be the salvation of many of the world's endangered languages, scientists believe.
Of the 7,000 or so languages spoken on Earth today, about half are expected to be extinct by the century's end.
Globalisation is usually blamed, but some elements of the "modern world", especially digital technology, are pushing back against the tide.
North American tribes use social media to re-engage their young, for example.
Tuvan, an indigenous tongue spoken by nomadic peoples in Siberia and Mongolia, even has an iPhone app to teach the pronunciation of words to new students.
"Small languages are using social media, YouTube, text messaging and various technologies to expand their voice and expand their presence," said K David Harrison, an associate professor of linguistics at Swarthmore College and a National Geographic Fellow.
"It's what I like to call the flipside of globalisation. We hear a lot about how globalisation exerts negative pressures on small cultures to assimilate. But a positive effect of globalisation is that you can have a language that is spoken by only five or 50 people in one remote location, and now through digital technology that language can achieve a global voice and a global audience."
Harrison, who travels the world to seek out the last speakers of vanishing languages, has been describing his work here at the annual meeting of the American Association for the Advancement of Science (AAAS).
With National Geographic, he has just helped produce eight talking dictionaries.
These dictionaries contain more than 32,000 word entries in eight endangered languages. All the audio recordings have been made by native speakers, some of whom like Alfred "Bud" Lane are among the last fluent individuals in their native tongues.
Mr Lane speaks a language known as Siletz Dee-ni, which is restricted to a small area on the central Oregon coast.
"Linguists came in and labelled our language moribund, meaning it was heading for the ash heap of history; and our tribal people and our council decided that wasn't going to happen. So we devised a plan to go forward to start teaching our dialect here in the Siletz Valley," he told the meeting.
Mr Lane has sat down and recorded 14,000 words for the online dictionary. "Nothing takes the place of speakers speaking to other speakers, but this bridges a gap that was just sorely needed in our community and our tribe."
Margaret Noori is an expert in Native American studies at the University of Michigan and a speaker of Anishinaabemowin, which is the sovereign language of over 200 indigenous "nations" in Canada and the US. These communities are heavy users of Facebook.
"What we do with technology is try to connect people," Prof Noori said. "All of it is to keep the language."
Dr Harrison says not all languages can survive, and many inevitably will be lost as remaining speakers die off. But he says the new digital tools do offer a way back from the brink for a lot of languages that seemed doomed just a few years ago.
He told BBC News: "Everything that people know about the planet, about plants, animals, about how to live sustainably, the polar ice caps, the different ecosystems that humans have survived in - all this knowledge is encoded in human cultures and languages, whereas only a tiny fraction of it is encoded in the scientific literature.
"If we care about sustainability and survival on the planet, we all benefit from having this knowledge base persevered."

Wednesday, February 15, 2012

Sea urchin spine structure inspires idea for concrete



Colourised SEM image of sea urchin spine (Marina Krumova, U Konstanz)The spines do not break cleanly, suggesting they are not made solely of single crystals


The precise structure of sea urchins' strong spines has been unravelled - and the find may contribute to stronger concrete in the future.
The tough spines are known to be made of calcium carbonate, which has a number of naturally occurring forms, some more brittle than others.
X-ray studies now show they are built from "bricks" of the crystal calcite, with a non-crystalline "mortar".
The spines serve as a defence against predators, hard and at the same time shock-absorbing. As a result of these properties, the spines are among the most-studied biomaterials.
Fire urchinThe urchins' strong spines serve as a defence against predators
But efforts to understand exactly how they are put together have yielded confusing results.
"Some people were arguing that the spine is a single crystal, and others who were looking at the mechanical properties were arguing that it's more like a glassy material," said senior author on the research Helmut Coelfen, from the University of Konstanz in Germany.
He told BBC News: "It still hasn't been resolved."
If the tough spines were single crystals, they should break cleanly along planes, as does mica or slate - but instead they break roughly, as glass or ceramic might.
To investigate further, the team started with sea urchin samples gathered in Beijing, looking at them with increasingly powerful imaging techniques.
Basic recipe
Along the way they gathered up expertise and collaborators from seven other institutions, starting with a standard light microscope, moving on to electron microscopes and then on to X-ray crystallography at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France.
"We started using more high-power techniques to go further down in the structure, and the further we go down, the more different modes of architecture and different organisations we find," said first author of the work Jong Seto, also from Konstanz.
X-ray scattering image of sea urchin spicule (ESRF)X-ray scattering tests showed patterns indicating 200 nanometre-sized "bricks"
The team discovered the bricks-and-mortar structure was made up of 92% calcite crystals (the bricks) bound together with 8% of calcium carbonate that has no crystal structure (the mortar).
This basic recipe builds up a range of structures that become apparent at different levels of magnification, making it what is known as a mesocrystal.
"With the help of these different techniques we were able to understand from the nanometre scale all the way to the millimetre scale how everything is arranged," Dr Seto told BBC News.
Mimicking nature's solutions to the material challenges that sea urchins face could be helpful also for us on land, Prof Coelfen said.
"The most obvious application... is building materials, to get fracture-rsesistant materials by just copying or trying to copy that building principle," he explained.
"We are already working with two major international companies trying to improve the properties of concrete by trying to order the little nanoparticles in concrete to make it tougher and more fracture-resistant."

Crime chiefs agree to get tough on illegal tiger trade



Tiger (Getty Images/Panoramic Images)About 4,000 tigers are estimated to remain in the wild


Crime chiefs from countries with populations of wild tigers have agreed to work together in order to combat the illegal trade in the big cats.
Heads of police and customs from 13 nations agreed to tighten controls and improve cross-border co-operation at a two-day meeting in Bangkok.
Only six subspecies remain, with fewer than 1,000 tigers in each group.
Smuggling of tiger parts is one of the main threats facing the planet's remaining big cats, say experts.

In detail: Tigers

Tiger (Image: AFP)
  • Scientific name: Panthera tigris
  • There are six remaining subspecies: Amur; northern Indochinese; Malayan; Sumatran; Bengal and South China
  • Three subspecies are now classified as extinct: Bali; Javan and Caspian
  • Tigers' historical range once spread across Asia, from Turkey to the far east of Russia
  • Over the past century, the animals have lost 93% of their historical range
  • It is estimated that each adult tiger needs to kills "50 large prey" each year, but they are also opportunistic hunters, capturing fish, birds, reptiles etc
  • Tiger habitats are primarily forests or scrubland
(Source: IUCN Red List)
The seminar in Thailand's capital, organised by Interpol and hosted by the International Consortium on Combating Wildlife Crime (ICCWC), was attended by 26 senior crime officials and representatives from partner organisations, including the Convention on International Trade in Endangered Species (Cites).
'Natural heritage abuse'
"[Our efforts to fight tiger crime] must not just result in seizures - they must result in prosecutions, convictions and strong penalties to stop the flow of contraband," said John Scanlon, Cites secretary general.
"If we get the enforcement system right for the tiger, we will help save countless other species together with their ecosystems."
Jean-Michel Louboutin, Interpol's executive director of police services, observed: "This important seminar has highlighted the environmental crime challenges facing senior law enforcement officers, and the need for enhanced international co-operation.
"Criminals cannot prosper from abusing our shared national heritage."
Delegates also used the meeting to formally endorse the Interpol-led Project Predator.
The initiative, launched in November 2011, has three main aims:
  • organising collaborative, high-level international efforts to improve political will to tackle the problem of illegal trade in tiger parts
  • transforming politicians' will to act into tangible support from government departments and agencies
  • training enforcement officers in the necessary skills
Project Predator is also encouraging countries to establish National Tiger Crime Task Forces, which will form working partnerships with Interpol, in order to provide "modern intelligence-led enforcement practices for tiger conservation".
Interpol said the project would not be limited to the protection of tigers, but would extend to the all of Asia's big cat species, such as the snow leopard and Asiatic lion, as these animals faced similar threats.
The meeting in Bangkok is the latest development in efforts to improve protection and conservation measures since a high-profile summit in November 2010 pledged to double the global population of tigers by 2022.
At the gathering in St Petersburg, Russia, senior political figures from the 13 range nations pledged to protect tiger habitats, address poaching, illegal trade and provide the financial resources for the plan.
Over the past century, tiger numbers have dropped from about 100,000 to about 4,000 tigers in the wild today.
And over the past decade, there has been a 40% decline, with conservationists warning that some populations were expected to disappear completely within 20 years unless urgent action was taken.

Friday, February 10, 2012

America and Eurasia 'to meet at north pole'




How the new continent of Amasia might look


America and Eurasia will crash into each other over the North Pole in 50-200 million years time, according to scientists at Yale University.
They predict Africa and Australia will join the new "supercontinent" too, which will mark the next coming together of the Earth's land masses.
The continents are last thought to have come together 300 million years ago into a supercontinent called Pangaea.
Details are published in the journal Nature.


The land masses of the Earth are constantly moving as the Earth's tectonic activity occurs. This generates areas such as the Mid-Atlantic Ridge, where Iceland has formed, and areas such as that off the coast of Japan, where one plate rides over another.
Geologists believe that, over billions of years, these shifting plates have driven the continents together periodically, creating the hypothesised supercontinents of Nuna 1.8 billion years ago, Rodinia a billion years ago, and then Pangaea 300 million years ago.
The next supercontinent has already been given the working title of Amasia, as it is expected to involve the convergence of the Americas and Asia.
What the researchers have set out to do is predict when and where it will form by looking back at where its predecessors emerged.
"We're all pretty familiar with the concept of Pangaea, but there hasn't been much convincing data to suggest how the supercontinents take shape," Ross Mitchell of Yale University told BBC News.
"In our model, we actually have North America and South America joining by closing the Caribbean Sea and the Arctic Sea closing and connecting the Americas and Asia."
'Better insight'
The model puts the repositioned Americas within what is known as the Pacific "ring of fire". Europe, part of the Eurasian land mass, Africa and Australia are predicted to join the merging continent, with only Antarctica left out.
The prediction is based on analysis of magnetic data locked into rocks around the world which betray the magnetic orientation of those rocks in past ages.
An animation showing plate motions for the past 500 million years and the rise and fall of the previous supercontinent Pangae"Ancient rocks when they form, whether it's lava cooling or sedimentary rock solidifying, will lock in the magnetic orientation," explained Mr Mitchell. "But while this indicates latitude very accurately, historically we haven't had indicators of longitude.
"We found that after each historical supercontinent had assembled, this whole supercontinent would undergo a series of back-and-forth rotations about a stable axis on the equator.
"This led them to the view that that each successive supercontinent forms 90 degrees away from its predecessor. Previous studies have suggested supercontinents would form either in the same part of the globe or on alternating sides of the globe.
Commenting on the paper, Dr David Rothery, a geologist with the Open University, said the new research offered us a better insight into the history of our planet.
"We can understand past environments better if we know exactly where they were," he told BBC News. "I don't think as a European I care whether continents are going to converge over the North Pole or whether Britain crashes into America in the far future. Predicting into the future is of far less concern than what happened in the past."

Threshold broken for tiny lasers



Scanning electron micrograph of nanoscale laser (M Khajavikhan et al)The cavity where the laser light is generated is less than 100 billionths of a metre across


Scientists have shown off the smallest-ever laser that works at the colours of light used in telecommunications and at room temperature.
The tiny light sources switch on with no "threshold", meaning they operate much more efficiently than earlier, small laser attempts.
They are just one-fifteenth the size of the light waves that they produce.
The advance, described in Nature, may help bring about faster computers or in future "optical computing" approaches.
Lasers are ubiquitous in daily life, from supermarket checkouts to CD players, but the quest for a smaller laser has been underway for years.
The principal application for the tiny lights would be in computing and telecommunications. Laser beams can, in principle, carry vast amounts of information faster than traditional semiconductor electronics.
But as the laser "cavities" in which light waves are amplified have shrunk to near the size of the light waves themselves, new effects have come into play.
Cable TV idea
Almost all lasers require that a certain threshold of energy is put in, after which the light waves can line up in sync to form a laser beam.
Much research in recent years has focused on confining lasers to tiny boxes made from metals.
However, at such minuscule scales, much of the energy that is put in to create a laser beam - and the light that comes out along with it - is wasted.
That raises the threshold energy so high as to make the resulting lasers impractical.

Start Quote

We feel this is just a beginning of a new family of light emitters with superior characteristics”
Mercedeh KhajavikhanUniversity of California, San Diego
The trick in the new work, said lead author Mercedeh Khajavikhan of the University of California, San Diego (UCSD), was to use not a box but a cylinder, in a so-called co-axial arrangement.
"Most people are familiar with co-axial cables that bring TV signals to their homes," Dr Khajavikhan told BBC News.
"What they may not be very familiar with is that co-axial structures can support a [laser beam], no matter how much they are shrunk in size."
Dr Khajavikhan and a team of colleagues from UCSD's department of electrical and computer engineering fabricated a number of the lasers - just 200 millionths of a millimetre high - with a metal rod at their centres, surrounded by a mix of semiconductor materials.
They put energy into the tiny lasers using a much larger laboratory laser, and found that the tiny lasers were able to harness all that energy, focusing it into laser beams of colours that are used in the telecommunications industry - all switched on with no threshold.
While they are not the smallest lasers ever made, the ease of fabrication of the team's tiny lights - and the fact that they work at room temperature - makes them attractive for future applications.
The first step will be to adjust the approach to work using not another laser but with electricity - similar to more familiar lasers in CD players and laser pointers.
With that, Dr Khajavikhan said the team "expect this work to have major impacts in several areas" - namely the ferrying of optical information on chips and, eventually, to all-optical computing technology.
Senior author on the research, Prof Shaya Fainman, said: "We feel this is just a beginning of a new family of light emitters with superior characteristics, and many advances in this new area are yet to come."

Wednesday, February 8, 2012

Threshold broken for tiny lasers



Scanning electron micrograph of nanoscale laser (M Khajavikhan et al)The cavity where the laser light is generated is less than 100 billionths of a metre across


Scientists have shown off the smallest-ever laser that works at the colours of light used in telecommunications and at room temperature.
The tiny light sources switch on with no "threshold", meaning they operate much more efficiently than earlier, small laser attempts.
They are just one-fifteenth the size of the light waves that they produce.
The advance, described in Nature, may help bring about faster computers or in future "optical computing" approaches.
Lasers are ubiquitous in daily life, from supermarket checkouts to CD players, but the quest for a smaller laser has been underway for years.
The principal application for the tiny lights would be in computing and telecommunications. Laser beams can, in principle, carry vast amounts of information faster than traditional semiconductor electronics.
But as the laser "cavities" in which light waves are amplified have shrunk to near the size of the light waves themselves, new effects have come into play.
Cable TV idea
Almost all lasers require that a certain threshold of energy is put in, after which the light waves can line up in sync to form a laser beam.
Much research in recent years has focused on confining lasers to tiny boxes made from metals.
However, at such minuscule scales, much of the energy that is put in to create a laser beam - and the light that comes out along with it - is wasted.
That raises the threshold energy so high as to make the resulting lasers impractical.

Start Quote

We feel this is just a beginning of a new family of light emitters with superior characteristics”
Mercedeh KhajavikhanUniversity of California, San Diego
The trick in the new work, said lead author Mercedeh Khajavikhan of the University of California, San Diego, was to use not a box but a cylinder, in a so-called co-axial arrangement.
"Most people are familiar with co-axial cables that bring TV signals to their homes," Dr Khajavikhan told BBC News.
"What they may not be very familiar with is that co-axial structures can support a [laser beam], no matter how much they are shrunk in size."
The team fabricated a number of the lasers - just 200 millionths of a millimetre high - with a metal rod at their centres, surrounded by a mix of semiconductor materials. They put energy into the tiny lasers using a much larger laboratory laser.
They found that the tiny lasers were able to harness all that energy, focusing it into laser beams of colours that are used in the telecommunications industry - all switched on with no threshold.
While they are not the smallest lasers ever made, the ease of fabrication of the team's tiny lights - and the fact that they work at room temperature - makes them attractive for future applications.
The first step will be to adjust the approach to work using not another laser but with electricity - similar to more familiar lasers in CD players and laser pointers.
With that, Dr Khajavikhan said the team "expect this work to have major impacts in several areas" - namely the ferrying of optical information on chips and, eventually, to all-optical computing technology.
"We feel this is just a beginning of a new family of light emitters with superior characteristics, and many advances in this new area are yet to come," she said.