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Earthquakes make gold veins -- pressure changes in Earth crust cause precious metals to deposit

Earthquakes make gold veins -- pressure changes in Earth crust cause precious metals to deposit | Amazing Science |

Scientists have long known that veins of gold are formed by mineral deposition from hot fluids flowing through cracks deep in Earth’s crust. But a study published today in Nature Geoscience has found that the process can occur almost instantaneously — possibly within a few tenths of a second.


The process takes place along 'fault jogs' — sideways zigzag cracks that connect the main fault lines in rock, says first author Dion Weatherley, a seismologist at the University of Queensland in Brisbane, Australia.

When an earthquake hits, the sides of the main fault lines slip along the direction of the fault, rubbing against each other. But the fault jogs simply open up. Weatherley and his co-author, geochemist Richard Henley at the Australian National University in Canberra, wondered what happens to fluids circulating through these fault jogs at the time of the earthquake.


What their calculations revealed was stunning: a rapid depressurization that sees the normal high-pressure conditions deep within Earth drop to pressures close to those we experience at the surface. For example, a magnitude-4 earthquake at a depth of 11 kilometres would cause the pressure in a suddenly opening fault jog to drop from 290 megapascals (MPa) to 0.2 MPa. (By comparison, air pressure at sea level is 0.1 MPa.) “So you’re looking at a 1,000-fold reduction in pressure,” Weatherley says.


Big earthquakes will produce bigger pressure drops, but for gold-vein formation, that seems to be overkill. More interesting, Weatherley and Henley found, is that even small earthquakes produce surprisingly big pressure drops along fault jogs. “We went all the way to magnitude –2,” Weatherley says — an earthquake so small, he adds, that it involves a slip of only about 130 micrometres along a mere 90 centimetres of the fault zone. “You still get a pressure drop of 50%,” he notes.

That, Weatherley adds, might be one of the reasons that the rocks in gold-bearing quartz deposits are often marbled with a spider web of tiny gold veins. “You [can] have thousands to hundreds of thousands of small earthquakes per year in a single fault system,” he says. “Over the course of hundreds of thousands of years, you have the potential to precipitate very large quantities of gold. Small bits add up.”


Weatherley says that prospectors might be able to use remote sensing techniques to find new gold deposits in deeply buried rocks in which fault jogs are common. “Fault systems with lots of jogs can be places where gold can be distributed,” he explains.


But Taka’aki Taira, a seismologist at the University of California, Berkeley, thinks that the finding might have even more scientific value. That’s because, in addition to showing how quartz deposits might form in fault jogs, the study reveals how fluid pressure in the jogs rebounds to its original level — something that could affect how much the ground moves after the initial earthquake.

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CRISPR-CAS Could Generate a Hypoallergenic Peanut But Anti-GMO Fear Gets In Its Way

CRISPR-CAS Could Generate a Hypoallergenic Peanut But Anti-GMO Fear Gets In Its Way | Amazing Science |

Anyone with a child in school is probably aware of the need for peanut free zones. You get a notice when your child returns from school on the first day stating that at least one child in their class has a peanut allergy, which means nothing with peanuts gets sent to school for your child’s lunch. If you are a parent of a child with a peanut allergy you understand how important and serious this is – your child is literally one errant Snickers bar away from death.

The general consensus is that food allergies have been on the rise in developed countries, although studies show a wide range of estimates based upon study techniques. A US review found the prevalence of self-reported peanut allergies ranged from 0-2%. A European review found the average estimate to be 2.2% – around 2% is usually the figure quoted. In a direct challenge study, at age 4, 1.1% of the 1218 children were sensitized to peanuts, and 0.5% had had an allergic reaction to peanuts. That means there are millions of people with peanut allergies.

So far there is no cure for the allergies themselves. Acute attacks can be treated with epinephrine, but there are cases of children dying (through anaphylaxis) even after multiple shots. The only real treatment is to obsessively avoid contact with the food in question. Peanuts, tree nuts, and shellfish are the good most likely to cause anaphylaxis.

There is, however, a potential solution. Researchers have been working for year on developing a cultivar of peanut that does not cause allergies. Attempts to achieve this through conventional breeding and hybridization have failed and does not seem likely to succeed. The only real hope of a hypoallergenic peanut is through genetic modification. We are, in fact, on the brink of achieving this goal, but anti-GMO fears are getting in the way.

There are 7 proteins that have been identified in peanuts that cause an allergic reaction. The allergic reaction from peanuts is entirely an IgE mediated Type I hypersensitivity response. The proteins crosslink with the IgE antibodies, which them bind to mast cells and basophils (cells in the immune system) causing a significant inflammatory response that clinically causes the allergic reaction. One peanut contains about 200mg of protein, and as little as 2mg is enough to cause objective symptoms of an allergic reaction.

What makes a food protein an allergen is interesting. About 700 amino acid sequences have been identified that help confer allergenicity to protein. These protein segments allow the protein to survive processing and digestion, and allow the protein to bind to IgE antibodies.

In 2005 a study was published showing that it is possible to silence the gene for the Ara H2 protein, the primary allergenic protein in peanuts. A 2008 follow up by the same team showed decreased allergenicity of the altered peanut. So where are our hypoallergenic peanuts? This is a complicated question, and I don’t think I can give a full answer.

The delay in marketing a hypoallergenic peanut seems to be due partly to technical issues – it turns out to be a lot more difficult to make the necessary changes than at first thought. However, it also seems to be due to the anti-GMO campaign, which has been scaring away investors and making politicians gun-shy.

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The biggest mystery in mathematics: Shinichi Mochizuki and the impenetrable proof

The biggest mystery in mathematics: Shinichi Mochizuki and the impenetrable proof | Amazing Science |
A Japanese mathematician claims to have solved one of the most important problems in his field.

Sometime on the morning of 30 August 2012, Shinichi Mochizuki quietly posted four papers on his website. The papers were huge — more than 500 pages in all — packed densely with symbols, and the culmination of more than a decade of solitary work. They also had the potential to be an academic bombshell. In them, Mochizuki claimed to have solved the abc conjecture, a 27-year-old problem in number theory that no other mathematician had even come close to solving. If his proof was correct, it would be one of the most astounding achievements of mathematics this century and would completely revolutionize the study of equations with whole numbers.

Mochizuki, however, did not make a fuss about his proof. The respected mathematician, who works at Kyoto University's Research Institute for Mathematical Sciences (RIMS) in Japan, did not even announce his work to peers around the world. He simply posted the papers, and waited for the world to find out.

Probably the first person to notice the papers was Akio Tamagawa, a colleague of Mochizuki's at RIMS. He, like other researchers, knew that Mochizuki had been working on the conjecture for years and had been finalizing his work. That same day, Tamagawa e-mailed the news to one of his collaborators, number theorist Ivan Fesenko of the University of Nottingham, UK. Fesenko immediately downloaded the papers and started to read. But he soon became “bewildered”, he says. “It was impossible to understand them.”

Fesenko e-mailed some top experts in Mochizuki's field of arithmetic geometry, and word of the proof quickly spread. Within days, intense chatter began on mathematical blogs and online forums (see Nature; 2012). But for many researchers, early elation about the proof quickly turned to scepticism. Everyone — even those whose area of expertise was closest to Mochizuki's — was just as flummoxed by the papers as Fesenko had been. To complete the proof, Mochizuki had invented a new branch of his discipline, one that is astonishingly abstract even by the standards of pure maths. “Looking at it, you feel a bit like you might be reading a paper from the future, or from outer space,” number theorist Jordan Ellenberg, of the University of Wisconsin–Madison, wrote on his blog a few days after the paper appeared.

Three years on, Mochizuki's proof remains in mathematical limbo — neither debunked nor accepted by the wider community. Mochizuki has estimated that it would take an expert in arithmetic geometry some 500 hours to understand his work, and a maths graduate student about ten years. So far, only four mathematicians say that they have been able to read the entire proof.

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DNA ‘vaccine’ that sterilizes mice, could lead to one-shot birth control

DNA ‘vaccine’ that sterilizes mice, could lead to one-shot birth control | Amazing Science |

Animal birth control could soon be just a shot away: A new injection makes male and female mice infertile by tricking their muscles into producing hormone-blocking antibodies. If the approach works in dogs and cats, researchers say, it could be used to neuter and spay pets and to control reproduction in feral animal populations. A similar approach could one day spur the development of long-term birth control options for humans.

“This looks incredibly promising,” says William Swanson, director of animal research at the Cincinnati Zoo and Botanical Garden in Ohio. “We’re all very excited about this approach; that it’s going to be the one that really works.”

For decades, the go-to methods for controlling animal reproduction have been spay or neuter surgeries. But the surgeries, which require animals to be anesthetized, can be expensive—one reason so many dogs and cats remain unfixed and feral animal populations continue to grow. Nearly 2.7 million dogs and cats were euthanized in U.S. shelters last year. A cheaper, faster method of sterilization is considered a holy grail for animal population control. 

To get there, researchers have already created vaccines that trigger an immune response in animals. This response produces antibodies that block gonadotropin-releasing hormone (GnRH), required by all mammals to turn on the pathways that spur egg or sperm development. The vaccines in this class—including deer contraceptive GonaCon—have been shown to effectively work as both male and female birth control in animals. But, like many human immunizations, the vaccines rely on an immune response that eventually dwindles away, forcing the use of booster shots every few years.

Biologist Bruce Hay of the California Institute of Technology in Pasadena and colleagues took a different approach to blocking GnRH. Rather than rely on animals’ immune systems to create antibodies, he and his colleagues engineered a piece of DNA that—when packaged inside inactive virus shells and injected into mice—turned their muscle cells into anti-GnRH antibody factories. Because muscle cells are some of the longest lasting in the body, they continue to churn out the antibodies for 10 or more years. Both male and female mice with high enough levels of the antibodies were rendered completely infertile when Hay’s team allowed them to mate 2 months later, the team reports online today in Current Biology.

Via Integrated DNA Technologies
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Scientists find smallest life forms on Earth

Scientists find smallest life forms on Earth | Amazing Science |

Over the last two decades, scientists have argued back and forth on whether or not ultra-small bacteria exist. The argument has been fueled, in part, by the1996 find of ultra-tiny fossil microorganisms on a meteorite from the planet MarsBut earlier this year, researchers at the University of California, Berkeley and the Department of Energy’s Lawrence Berkeley National Laboratory have captured detailed cryogenic electron microscopy images of ultra-small bacteria. These cells are now believed to be as small as a cell can get and still possess sufficient internal material needed to sustain life.

The first author of the study, Birgit Luef, is now a researcher at NTNU’s Department of Biotechnology. The publication was the result of her postdoctoral work at UC Berkeley. The researchers found several kinds of bacteria from three microbial phyla that are poorly understood. The bacteria were in groundwater and are thought to be quite common. But what surprised Luef and her colleagues was that the bacteria were  close to and in some cases smaller than what many scientists have long considered the lower size limit of life. They reported the findings in the spring in the journal Nature Communications.

The cells had an average volume 0.009 ± 0.002 cubic microns, meaning 150 of the bacteria would fit inside a single cell of Escherichia coli.

Via Mariaschnee
Ed Rybicki's comment, Today, 4:25 AM
And of course, AGAIN they ignore the fact that viruses are alive...but it's nice that FINALLY someone seems to have nailed the nanobacteria we kept hearing about.
Ed Rybicki's curator insight, Today, 4:27 AM

Cell-based: because circoviruses are the smallest organisms at 1.9 - 2 Kb of DNA B-)

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Physics Nobel Prize 2015 for missing piece in neutrino mass puzzle

Physics Nobel Prize 2015 for missing piece in neutrino mass puzzle | Amazing Science |

Two scientists won the Nobel Prize in physics Tuesday for key discoveries about a cosmic particle that whizzes through space at nearly the speed of light, passing easily through Earth and even your body.

Takaaki Kajita of Japan and Arthur McDonald of Canada were honored for showing that these tiny particles, called neutrinos, have mass. That's the quality we typically experience as weight.

"The discovery has changed our understanding of the innermost workings of matter and can prove crucial to our view of the universe," the Royal Swedish Academy of Sciences said in awarding the prize.

The work dispelled the long-held notion that neutrinos had no mass. Neutrinos come in three types, or "flavors," and what the scientists actually showed is that neutrinos spontaneously shift between types. That in turn means they must have mass.

Via José Gonçalves, John Purificati
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Building New Thoughts From Scratch

Building New Thoughts From Scratch | Amazing Science |

Human brains flexibly combine the meanings of words to compose structured thoughts. For example, by combining the meanings of “bite,” “dog,” and “man,” we can think about a dog biting a man, or a man biting a dog. In two functional magnetic resonance imaging (fMRI) experiments using multivoxel pattern analysis (MVPA), a team of scientists now identified a region of left mid-superior temporal cortex (lmSTC) that flexibly encodes “who did what to whom” in visually presented sentences. They found that lmSTC represents the current values of abstract semantic variables (“Who did it?” and “To whom was it done?”) in distinct subregions. Experiment 1 first identified a broad region of lmSTC whose activity patterns (i) facilitate decoding of structure-dependent sentence meaning (“Who did what to whom?”) and (ii) predicted affect-related amygdala responses that depend on this information (e.g., “the baby kicked the grandfather” vs. “the grandfather kicked the baby”). Experiment 2 then identified distinct, but neighboring, subregions of lmSTC whose activity patterns carry information about the identity of the current “agent” (“Who did it?”) and the current “patient” (“To whom was it done?”). These neighboring subregions lie along the upper bank of the superior temporal sulcus and the lateral bank of the superior temporal gyrus, respectively. At a high level, these regions may function like topographically defined data registers, encoding the fluctuating values of abstract semantic variables. This functional architecture, which in key respects resembles that of a classical computer, may play a critical role in enabling humans to flexibly generate complex thoughts.

Via Donald J Bolger
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Rescooped by Dr. Stefan Gruenwald from DNA & RNA Research!

Gene-editing record smashed in pigs: 60 genes edited

Gene-editing record smashed in pigs: 60 genes edited | Amazing Science |

Researchers modify more than 60 genes in effort to enable organ transplants into humans.

For decades, scientists and doctors have dreamed of creating a steady supply of human organs for transplantation by growing them in pigs. But concerns about rejection by the human immune system and infection by viruses embedded in the pig genome have stymied research. Now, bymodifying more than 60 genes in pig embryos — ten times more than have been edited in any other animal — researchers believe they may have produced a suitable non-human organ donor.

The work was presented on 5 October 2015 at a meeting of the US National Academy of Sciences (NAS) in Washington DC on human gene editing. Geneticist George Church of Harvard Medical School in Boston, Massachusetts, announced that he and colleagues had used the CRISPR/Cas9 gene-editing technology to inactivate 62 porcine endogenous retroviruses (PERVs) in pig embryos. These viruses are embedded in all pigs’ genomes and cannot be treated or neutralized.It is feared that they could cause disease in human transplant recipients.

Church’s group also modified more than 20 genes in a separate set of pig embryos, including genes that encode proteins that sit on the surface of pig cells and are known to trigger a human immune response or cause blood clotting. Church declined to reveal the exact genes, however, because the work is as yet unpublished.Eventually, pigs intended for organ transplants would need both these modifications and the PERV deletions.

Via Integrated DNA Technologies
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Team succeeds in producing photoreceptors from human embryonic stem cells

Team succeeds in producing photoreceptors from human embryonic stem cells | Amazing Science |

Age-related macular degeneration (AMRD) could be treated by transplanting photoreceptors produced by the directed differentiation of stem cells, thanks to findings published today by Professor Gilbert Bernier of the University of Montreal and its affiliated Maisonneuve-Rosemont Hospital. ARMD is a common eye problem caused by the loss of cones. Bernier's team has developed a highly effective in vitro technique for producing light sensitive retina cells from human embryonic stem cells. "Our method has the capacity to differentiate 80% of the stem cells into pure cones," Professor Gilbert explained. "Within 45 days, the cones that we allowed to grow towards confluence spontaneously formed organised retinal tissue that was 150 microns thick. This has never been achieved before."

In order to verify the technique, Bernier injected clusters of retinal cells into the eyes of healthy mice. The transplanted photoreceptors migrated naturally within the retina of their host. "Cone transplant represents a therapeutic solution for retinal pathologies caused by the degeneration of photoreceptor cells," Bernier explained. "To date, it has been difficult to obtain great quantities of human cones." His discovery offers a way to overcome this problem, offering hope that treatments may be developed for currently non-curable degenerative diseases, like Stargardt disease and ARMD. "Researchers have been trying to achieve this kind of trial for years," he said. "Thanks to our simple and effective approach, any laboratory in the world will now be able to create masses of photoreceptors. Even if there's a long way to go before launching clinical trials, this means, in theory, that will be eventually be able to treat countless patients."

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Video shows how HIV spreads in real time

Video shows how HIV spreads in real time | Amazing Science |

How retroviruses like HIV spread in their hosts had been unknown — until a Yale team devised a way to watch it actually happen in a living organism. The elaborate and sometimes surprising steps the virus takes to reach and spread in the lymph nodes of a mouse have been captured on videos and described in the Oct. 2 issue of the journal Science.

“It’s all very different than what people thought,” said Walther Mothes, associate professor of microbial pathogenesis and co-senior author the paper.

Tracking fluorescently stained viruses in mice, the Yale team led by Mothes and co-senior author Priti Kumar, assistant professor of medicine and microbial pathogenesis, used sophisticated imaging technology to capture the action as the viral particles bind to macrophages via a sticky protein that is located at the capsule of the lymph node.

But that is only the first step of the journey. The captured viral particles open to a rare type of B-cell, seen in red in the accompanying movie. The virus particles then attach themselves to the tail of these B-cells and are dragged into the interior of the lymph node. In one to two days, these B-cells establish stable connections with tissue, enabling full transmission of the virus.

The insights provided by the videos identify a potential way to prevent HIV from infecting surrounding tissue. If researchers could develop a way to block the action of the sticky protein the virus uses to bind to macrophages, then the virus’ transmission could be halted, Mothes suggested.

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Elon Musk: Fully autonomous cars with 1,000km electric range are coming in 2017

Elon Musk: Fully autonomous cars with 1,000km electric range are coming in 2017 | Amazing Science |

Elon Musk believes Tesla cars will be fully autonomous by 2018, and have an all-electric range of more than 1,000km, double what it is today. He also predicts that by 2035 all new cars will not require a driver.

A renowned futurist and CEO of Tesla and SpaceX, Musk predicts that the range of the Model S can be increased by between 5% and 10% every year, as battery technology improves. He also claims the AutoPilot self-driving feature currently being beta tested by Tesla will be rolled-out to all compatible Model S vehicles by the end of October. AutoPilot provides automatic steering, accelerating and braking on motorways, but only in countries which have updated their road laws to allow it.

In an interview on Dutch television, Musk said: "My guess is that we could probably break 1,000km within a year or two. I'd say 2017 for 2020 I guess we could probably make a car go 1,200km. I think maybe 5-10% a year [improvement], something like that." A Model S was recently driven 452 miles (723km) on a single charge, but drove at an average speed of just 24mph. Musk says his predictions account for driving at a more realistic speed. Musk added that AutoPilot will be switched on in a month's time, adding: "My guess for when we'll have full autonomy is about three years, approximately three years." This is much sooner than 2020, when analysts had expected to see autonomous cars from Google - and possible Apple - go on sale.

But this is with a caveat. "Regulators will not allow full autonomy for one to two years – maybe one to three years – after that," Musk said. "It depends on the particular market; in some markets the regulators will be more forward leaning than others. But in terms of when [full autonomy] will be technologically possible, I think three years."

Looking even further ahead, Musk predicts that – providing "civilisation is still around" – by 2035 "we'll see a very large percentage of cars being electric [on the road] probably all cars being built will have full autonomy in 20 years." Again, however, a caveat exists, in that cars are not replaced as often as smartphones, so it will take a considerable amount of time for all vehicles on the world's roads (around 2.5 billion) to become electric and autonomous. Musk reckons it would take another 20 years to fully replace all cars and trucks being used in 2035 with electric vehicles.

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How to make 3-D objects totally disappear

How to make 3-D objects totally disappear | Amazing Science |

An ultra-thin invisibility “skin” cloak that can conform to the shape of an object and conceal it from detection with visible light has been developed by scientists at Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley.

Working with blocks of gold nanoantennas, the Berkeley researchers created a “skin cloak” just 80 nanometers in thickness that was wrapped around a three-dimensional object about the size of a few biological cells and shaped with multiple bumps and dents. The surface of the skin cloak was meta-engineered to reflect light waves, making the object invisible to optical detection when the cloak is activated.

“This is the first time a 3D object of arbitrary shape has been cloaked from visible light,” said Xiang Zhang, director of Berkeley Lab’s Materials Sciences Division. “Our ultra-thin cloak now looks like a coat. It is easy to design and implement, and is potentially scalable for hiding macroscopic objects.”

Zhang, who holds the Ernest S. Kuh Endowed Chair at UC Berkeley and is a member of the Kavli Energy NanoSciences Institute at Berkeley (Kavli ENSI), is the corresponding author of a paper describing this research in the journal Science.

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Earth-like planets around small stars likely have protective magnetic fields, aiding chance for life

Earth-like planets around small stars likely have protective magnetic fields, aiding chance for life | Amazing Science |
Earth-like planets orbiting close to small stars probably have magnetic fields that protect them from stellar radiation and help maintain surface conditions that could be conducive to life, according to research from astronomers at the University of Washington.

A planet's magnetic field emanates from its core and is thought to deflect the charged particles of the stellar wind, protecting the atmosphere from being lost to space. Magnetic fields, born from the cooling of a planet's interior, could also protect life on the surface from harmful radiation, as the Earth's magnetic field protects us.

Low-mass stars are among the most common in the universe. Planets orbiting near such stars are easier for astronomers to target for study because when they transit, or pass in front of, their host star, they block a larger fraction of the light than if they transited a more massive star. But because such a star is small and dim, its habitable zone—where an orbiting planet gets the heat necessary to maintain life-friendly liquid water on the surface—also lies relatively close in.

And a planet so close to its star is subject to the star's powerful gravitational pull, which could cause it to become tidally locked, with the same side forever facing its host star, as the moon is with the Earth. That same gravitational tug from the star also creates tidally generated heat inside the planet, or tidal heating. Tidal heating is responsible for driving the most volcanically active body in our solar system, Jupiter's moon Io.

In a paper published Sept. 22 in the journal Astrobiology, lead author Peter Driscoll sought to determine the fate of such worlds across time: "The question I wanted to ask is, around these small stars, where people are going to look for planets, are these planets going to be roasted by gravitational tides?" He was curious, too, about the effect of tidal heating on magnetic fields across long periods of time.

Their simulations ranged from one stellar mass—stars the size of our sun—down to about one-tenth of that size. By merging their models, they were able, Barnes said, "to produce a more realistic picture of what is happening inside these planets." Barnes said there has been a general feeling in the astronomical community that tidally locked planets are unlikely to have protective magnetic fields "and therefore are completely at the mercy of their star." This research suggests that assumption false.

Far from being harmful to a planet's magnetic field, tidal heating can actually help it along—and in doing so also help the chance for habitability. This is because of the somewhat counterintuitive fact that the more tidal heating a planetary mantle experiences, the better it is at dissipating its heat, thereby cooling the core, which in turn helps create the magnetic field.

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Mysterious ripples found racing through planet-forming disc: Unique structures spotted around nearby star

Mysterious ripples found racing through planet-forming disc: Unique structures spotted around nearby star | Amazing Science |

sing images from the NASA/ESA Hubble Space Telescope and ESO's Very Large Telescope, astronomers have discovered never-before-seen structures within a dusty disc surrounding a nearby star. The fast-moving wave-like features in the disc of the star AU Microscopii are unlike anything ever observed, or even predicted, before now. The origin and nature of these features present a new mystery for astronomers to explore. The results are published in the journal Nature on 8 October 2015.

AU Microscopii, or AU Mic for short, is a young, nearby star surrounded by a large disc of dust [1]. Studies of such debris discs can provide valuable clues about how planets, which form from these discs, are created.

Astronomers have been searching AU Mic's disc for any signs of clumpy or warped features, as such signs might give away the location of possible planets. And in 2014 they used the powerful high-contrast imaging capabilities of ESO's newly installed SPHERE instrument, mounted on the Very Large Telescope for their search -- and discovered something very unusual.

"Our observations have shown something unexpected," explains Anthony Boccaletti of the Observatoire de Paris, France, lead author on the paper. "The images from SPHERE show a set of unexplained features in the disc which have an arch-like, or wave-like, structure, unlike anything that has ever been observed before."

Five wave-like arches at different distances from the star show up in the new images, reminiscent of ripples in water. After spotting the features in the SPHERE data the team turned to earlier images of the disc taken by the NASA/ESA Hubble Space Telescope in 2010 and 2011 to see whether the features were also visible in these [2]. They were not only able to identify the features on the earlier Hubble images -- but they also discovered that they had changed over time. It turns out that these ripples are moving -- and very fast!

"We reprocessed images from the Hubble data and ended up with enough information to track the movement of these strange features over a four-year period," explains team member Christian Thalmann (ETH Zürich, Switzerland). "By doing this, we found that the arches are racing away from the star at speeds of up to about 40,000 kilometers/hour!"

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Anti-parasite drugs sweep Nobel prize in medicine 2015

Anti-parasite drugs sweep Nobel prize in medicine 2015 | Amazing Science |
Three scientists who developed therapies against parasitic infections have won this year's Nobel Prize in Physiology or Medicine.

The winners are: William C. Campbell, a microbiologist at Drew University in Madison, New Jersey; Satoshi Ōmura, a microbiologist at Kitasato University in Japan; and Youyou Tu, a pharmacologist at the China Academy of Chinese Medical Sciences in Beijing.

In the 1970s, Campbell and Ōmura discovered a class of compounds, called avermectins, that kill parasitic roundworms that cause infections such as river blindness and lymphatic filariasis. The most potent of these was released onto the market in 1981 as the drug ivermectin.

Tu, who won a Lasker prize in 2011, developed the antimalarial drug artemisinin in the late 1960s and 1970s. She is the first China-based scientist to win a science Nobel. “This certainly is fantastic news for China. We expect more to come in the future,” says Wei Yang, president of the nation’s main research-funding agency, the National Natural Science Foundation of China.

In the 1960s, the main treatments for malaria were chloroquine and quinine, but they were proving increasingly ineffective. So in 1967, China established a national project against malaria to discover new therapies. Tu and her team screened more than 2,000 Chinese herbal remedies to search for drugs with antimalarial activity. An extract from the wormwood plant Artemisia annua proved especially effective and by 1972, the researchers had isolated chemically pure artemisinin.

That Tu won the Nobel prize is "great news", says Yi Rao, a neuroscientist at Peking University in Beijing who has researched the discovery of artemisinin. "I’m very happy about this. She totally deserves it.”

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Uncovering The Spliceosome’s Secrets

Uncovering The Spliceosome’s Secrets | Amazing Science |

With a high-resolution structure of the mRNA-splicing machine now in hand, a new era of biological and pharmaceutical discovery is dawning.

Watching fruit flies buzz around the ripe bananas in your kitchen, you might think it’s a tad ludicrous, mortifying even, that humans have a similar number of genes—about 23,000—as the lowly insects. We are certainly more complex than Drosophila melanogaster, so what gives?

The answer lies in the spliceosome, a cellular machine that, at first glance, seems to do some pretty straightforward pruning of messenger RNA (mRNA).

As the cell transcribes your DNA’s nucleic acid sequence into RNA, the spliceosome lands on the newly forming mRNA strand, where it chops out unnecessary pieces, called introns, and joins together the leftover, essential sequences, called exons. The edited mRNA is then exported to the cell’s cytoplasm, where it gets translated into protein.

Most strands of unspliced mRNA, otherwise known as pre-mRNA, have about a dozen introns that can be removed. Yet the spliceosome doesn’t always link together the remaining exons in a straightforward manner. Sometimes the spliceosome intentionally skips an exon, or it reorders the exons, or it unexpectedly leaves an intron in the mix. On average, this variable editing process produces about 10 different proteins for every gene that we have. “Alternative splicing allows us to make the most out of every gene,” says Joan Steitz at Yale University School of Medicine. “Splicing is the reason we can have the same number of genes as the fruit fly Drosophila and yet be more complicated.”

This splice ‘n’ dice machine gives us our complexity, but it’s also exceedingly complex itself. So complex, in fact, that it’s taken decades and many twists and turns for scientists to figure out how it works. Because the spliceosome is so sophisticated, small hiccups in its operation can lead to biological malfunction and, ultimately, to disease. Discovery of the tiny machine has been a boon to drug developers, who are already developing drugs that target the spliceosome. They hope such molecules will treat the myriad diseases linked to splicing malfunction, including many cancers, some forms of blindness, and 10% of genetic diseases, such as spinal muscular atrophy and certain types of dwarfism.

What researchers now know is that cells assemble the spliceosome from an enormous cast of protein and RNA characters. These players work in unison, carrying out a gymnastics routine worthy of the Super Bowl halftime show. Five protein-RNA complexes, called ribonucleoproteins, and some 200 proteins come and go during different stages of human splicing. This machinery forms temporary assemblies that prep and then edit pre-mRNA, converting it into mRNA that can be read by the ribosome, another enormous ribonucleoprotein engine responsible for turning mRNA into protein.

Although it’s only about half the size of the ribosome, the spliceosome—with its ever-changing parts and rearrangements—is a much more dynamic machine, says Reinhard Lührmann of the Max Planck Institute for Biophysical Chemistry, in Göttingen, Germany. This has made the spliceosome one of structural biology’s most desirable targets and one of its most challenging foes: Many in the field say that the ribosome was a comparatively easy structure to solve, and even that was a feat so grand it earned the structural biologists who accomplished it a Nobel Prize.

So it was that scientists gasped in collective shock when a team of researchers—newcomers to the spliceosome field—published the first near-atomic-resolution structure of the splicing machinery in August. The scientists, led by Yigong Shi of Tsinghua University, in China, also published an accompanying paper on spliceosome function for good measure (Science 2015, DOI:10.1126/science.aac7629 and 10.1126/science.aac8159). “It was a total bombshell,” Yale’s Steitz says. “I never thought we’d see a complete structure this soon.”

Via Integrated DNA Technologies
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Crucial hurdle overcome in quantum computing: A two-qubit logic gate in silicon

Crucial hurdle overcome in quantum computing: A two-qubit logic gate in silicon | Amazing Science |
The significant advance, by a team at the University of New South Wales (UNSW) in Sydney appears today in the international journal Nature.

"What we have is a game changer," said team leader Andrew Dzurak, Scientia Professor and Director of the Australian National Fabrication Facility at UNSW. "We've demonstrated a two-qubit logic gate - the central building block of a quantum computer - and, significantly, done it in silicon. Because we use essentially the same device technology as existing computer chips, we believe it will be much easier to manufacture a full-scale processor chip than for any of the leading designs, which rely on more exotic technologies.

"This makes the building of a quantum computer much more feasible, since it is based on the same manufacturing technology as today's computer industry," he added. The advance represents the final physical component needed to realize the promise of super-powerful silicon quantum computers, which harness the science of the very small - the strange behavior of subatomic particles - to solve computing challenges that are beyond the reach of even today's fastest supercomputers.

In classical computers, data are rendered as binary bits, which are always in one of two states: 0 or 1. However, a quantum bit (or 'qubit') can exist in both of these states at once, a condition known as a superposition. A qubit operation exploits this quantum weirdness by allowing many computations to be performed in parallel (a two-qubit system performs the operation on 4 values, a three-qubit system on 8, and so on). "If quantum computers are to become a reality, the ability to conduct one- and two-qubit calculations are essential," said Dzurak, who jointly led the team in 2012 who demonstrated the first ever silicon qubit, also reported in Nature.

But until now, it had not been possible to make two quantum bits 'talk' to each other - and thereby create a logic gate - using silicon. But the UNSW team - working with Professor Kohei M. Itoh of Japan's Keio University - has done just that for the first time. The result means that all of the physical building blocks for a silicon-based quantum computer have now been successfully constructed, allowing engineers to finally begin the task of designing and building a functioning quantum computer.

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Yale team identifies tiny non-coding RNA that controls cholesterol

Yale team identifies tiny non-coding RNA that controls cholesterol | Amazing Science |

High levels of LDL cholesterol — the “bad” cholesterol — increase the risk of heart disease, the leading cause of death in the United States. A Yale-led research team has identified an RNA molecule that plays an important role in regulating cholesterol. Therapeutic targeting of this non-coding RNA markedly reduces LDL while boosting HDL, the good cholesterol.

The finding, published online ahead of print in Nature Medicine, may lead to new therapies designed to decrease high cholesterol and heart disease. The researchers used a high-throughput screening technique to identify which tiny RNA molecules, or microRNAs, influence LDL cholesterol levels in the blood. They found that a particular RNA, known as miR-148a, modifies LDL receptors in liver cells of both mice and humans. They also discovered that miR-148a suppresses a gene that is critical for controlling levels of HDL cholesterol. 

“The key finding is the identification of another molecular target that could be used for treating high levels of bad cholesterol, and potentially treating cardiovascular disease,” said Carlos Fernandez-Hernando, associate professor of comparative medicine and pathology, and the study’s senior author. “By blocking this microRNA pharmacologically, we can reduce bad cholesterol.”

“Our work also establishes miR-148a as a promising therapeutic target to increase levels of good cholesterol,” noted Leigh Goedeke, a post-doctoral associate at Yale and lead author of the study. “We may have found a new treatment option to simultaneously reduce two risk factors of heart disease.”

Via Integrated DNA Technologies
Rakesh Yashroy's curator insight, Today, 10:14 AM

A new (RNA) handle to control bad (LDL) cholesterol.

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How To Detect ANY Virus In A Patient's Blood

How To Detect ANY Virus In A Patient's Blood | Amazing Science |

Better diagnosis leads to better treatment – that’s well-known. Easier said than done, of course, since that’s not always possible when tests for diseases or infections take time to generate results, for example, or are inaccurate or insensitive. Take viruses: There is an abundance out there capable of causing disease, many of which can present similar symptoms or, perhaps worse, none at all. Detection can, therefore, be a bit of a nightmare, sometimes demanding a labor-intensive and costly suite of tests to get to the bottom of a case.

What if there was a universal, one-size-fits-all-test that could pick up any known virus in a sample, eliminating this time-consuming detective work? That might sound quite out of our clutches, but researchers at Washington University School of Medicine might just have achieved this long-awaited, eyebrow-raising feat.

“With this test, you don’t have to know what you’re looking for,” senior author Gregory Storch said in a statement. “It casts a broad net and can efficiently detect viruses that are present at very low levels. We think the test will be especially useful in situations where a diagnosis remains elusive after standard testing or in situations in which the cause of a disease outbreak is unknown.”

Describing their work in Genome Research, the results are pretty impressive. To make their “ViroCap,” the researchers began by creating a broad panel of sequences to be targeted by the test, which they generated using unique stretches of DNA or RNA found in viruses across 34 different human- and animal-infecting families. This resulted in millions of stretches of nucleic acid that can be used to capture matching strands in a sample, should they be present.

But the broad spectrum of this test is not its only remarkable quality: It’s so sensitive that it can even pick up slight variations in sequences, meaning that a virus’ subtype can also be identified – a feature not possible with many traditional tests. Although that wouldn’t necessarily change the way a patient is treated, it could aid disease surveillance.

To demonstrate its capabilities, the researchers took samples from a small group of patients at St. Louis Children’s Hospital and compared the results to those obtained from standard tests. While traditional sequencing managed to find viruses in the majority of the children, ViroCap also managed to pick up some common viruses that it had failed to detect. These included a flu virus and the virus responsible for chickenpox. In a second test run on a different group of children displaying fevers, the new test found an additional seven viruses to the 11 that the traditional testing managed to detect.  

All of this sounds great on paper, but of course it is not yet ready to be used in the clinic. Further trials are required first to check its accuracy on larger groups of people, as so far only a limited number of patients have been screened. But when the time comes, the team plans to make it widely available, which would be welcome in the face of outbreaks like Ebola. Furthermore, the team ultimately hopes to tweak it so that it can detect genetic material from other microbes, like bacteria. If that’s possible, we could have a seriously useful machine on our hands that could change diagnostic medicine for the better. 

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Easier way to fix hearts: Catheter aided by UV repairs holes without surgery

Easier way to fix hearts: Catheter aided by UV repairs holes without surgery | Amazing Science |

Harvard-affiliated researchers have designed a specialized catheter for fixing holes in the heart by using a biodegradable adhesive and patch. The team reported in the journal Science Translational Medicine that the catheter has been used successfully in animal studies to help close holes without requiring open-heart surgery.

Pedro del Nido, chief of cardiac surgery at Boston Children’s Hospital, the William E. Ladd Professor of Child Surgery at Harvard Medical School, and contributing author on the study, said the device represents a radical change in the way some kinds of cardiac defects are repaired. “In addition to avoiding open-heart surgery, this method avoids suturing into the heart tissue, because we’re just gluing something to it.”

Catheterizations are preferable to open-heart surgery because they don’t require stopping the heart, putting the patient on bypass, and cutting into the heart. The Heart Center at Boston Children’s is working toward the least invasive methods possible to correct heart defects, which are among the most common congenital defects.

Last winter, news of the unique adhesive patch was published in the same journal as the latest report. This represented a large step forward in the quest to reduce complications associated with repairing heart defects. While medical devices that remain in the body may be jostled out of place or fail to cover the hole as the body grows, the patch allows the heart tissue to create its own closure, and then it dissolves.

To truly realize the patch’s potential, however, the research team sought a way to deliver the patch without open-heart surgery. Their catheter device utilizes UV-light technology and can be used to place the patch in a beating heart.

The catheter is inserted through a vein in the neck or groin and directed to the defect within the heart. Once the catheter is in place, the clinician opens two positioning balloons: one around the front end of the catheter, passing through the hole, and one on the other side of the heart wall. The clinician then deploys the patch and turns on the catheter’s UV light.

The light reflects off of the balloon’s shiny interior and activates the patch’s adhesive coating. As the glue cures, pressure from the positioning balloons on either side of the patch help secure it in place. Finally, both balloons are deflated, and the catheter is withdrawn. Over time, normal tissue growth resumes, and heart tissue grows over the patch. The patch itself dissolves when it is no longer needed.

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Nobel prize 2015 for chemistry: Lindahl, Modrich and Sancar win for DNA repair

Nobel prize 2015 for chemistry: Lindahl, Modrich and Sancar win for DNA repair | Amazing Science |

The Nobel prize in chemistry has been awarded to Tomas Lindahl, Paul Modrich and Aziz Sancar for their research into the mechanisms that cells use to repair DNA.

From the moment an egg is fertilized it begins to divide. Two cells become four, four cells become eight. After one week a human embryo consists of 128 cells, each with its own set of genetic material. Unravel all that DNA and it would stretch for 300 meters. But many billions more divisions take place on the path to adulthood, until we carry enough DNA in our trillions of cells to reach 250 times to the sun and back. The most remarkable feat is how the genetic information is copied so faithfully. “From a chemical perspective, this ought to be impossible,” the Nobel committee said.

“All chemical processes are prone to random errors. Additionally, your DNA is subjected on a daily basis to damaging radiation and reactive molecules. In fact, you ought to have been a chemical chaos long before you even developed into a foetus,” they added.

Lindahl, Modrich and Sancar worked out how cells repair faults that inevitably creep in when DNA is copied time and time again, and mutations that arise under a barrage of environmental factors such as UV rays in sunlight.

Towards the end of the 1960s, many scientists considered DNA to be incredibly stable. But working at the Karolinska Institute in Stockholm, Lindahl worked out that there must be thousands of potentially damaging attacks on the genome every day – an onslaught that would make human life impossible.

Working with bacterial DNA, Lindahl began the search for enzymes that repair faulty genetic mateial. He focused on a weakness in the way the DNA letters, G, T, C and A, pair up. Normally, C (cytosine) pairs only with G (guanine), but C can lose an amino group which makes it pair up with A ( adenine) instead. If the mis-pairing stands, it creates a mutation the next time it is copied. Lindahl realised that cells must have a way to protect themselves from such a fate, and published details of the enzyme responsible in 1974.

Lindahl moved to the UK in the 1980s and became director of what is now Cancer Research UK’s Clare Hall Laboratory, a place known for its scientific creativity. There he worked out, step by step, the DNA repair processes in humans.

But DNA can also be disrupted by environmental factors, such as UV radiation. How organisms survived these mutations piqued the interest of Sancar who noticed that bacteria exposed to deadly doses of UV could repair themselves if lit up blue light. At the University of Texas in Dallas, he discovered an enzyme called photolyase that repairs UV-damaged DNA.

At Yale University, Sancar went on to identify enzymes that spot UV damage and then cut the DNA to remove the faulty genetic code. Later, at the University of North Carolina in Chapel Hill, he mapped the equivalent repair process in humans.

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BGI is planning to sell their gene-edited 'micropigs' as pets

BGI is planning to sell their gene-edited 'micropigs' as pets | Amazing Science |

Cutting-edge gene-editing techniques have produced an unexpected byproduct — tiny pigs that a leading Chinese genomics institute will soon sell as pets.

BGI in Shenzhen, the genomics institute that is famous for a series of high-profile breakthroughs in genomic sequencing, originally created the micropigs as models for human disease, by applying a gene-editing technique to a small breed of pig known as Bama. On 23 September 2015, at the Shenzhen International Biotech Leaders Summit in China, BGI revealed that it would start selling the pigs as pets. The animals weigh about 15 kilograms when mature, or about the same as a medium-sized dog.

At the summit, the institute quoted a price tag of 10,000 yuan (US$1,600) for the micropigs, but that was just to "help us better evaluate the market”, says Yong Li, technical director of BGI’s animal-science platform. In future, customers will be offered pigs with different coat colors and patterns, which BGI says it can also set through gene editing.

With gene editing taking biology by storm, the field's pioneers say that the application to pets was no big surprise. Some also caution against it. “It's questionable whether we should impact the life, health and well-being of other animal species on this planet light-heartedly,” says geneticist Jens Boch at the Martin Luther University of Halle-Wittenberg in Germany. Boch helped to develop the gene-editing technique used to create the pigs, which uses enzymes known as TALENs (transcription activator-like effector nucleases) to disable certain genes.

How to regulate the various applications of gene-editing is an open question that scientists are already discussing with agencies across the world. BGI agrees on the need to regulate gene editing in pets as well as in the medical research applications that make up the core of its micropig activities. Any profits from the sale of pets will be invested in this research. “We plan to take orders from customers now and see what the scale of the demand is,” says Li.

The decision to sell the pigs as pets surprised Lars Bolund, a medical geneticist at Aarhus University in Denmark who helped BGI to develop its pig gene-editing programme, but he admits that they stole the show at the Shenzhen summit. “We had a bigger crowd than anyone,” he says. “People were attached to them. Everyone wanted to hold them.”

They could meet a preexisting demand. In the United States, for instance, reports have surfaced of people who wanted a porcine lap pet, but were disappointed when animals touted as 'teacup' pigs weighing only 5 kilograms grew into 50-kilogram animals. Genetically-edited micropigs stay reliably small, the BGI team says.

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New flat transistor defies theoretical limit

New flat transistor defies theoretical limit | Amazing Science |
A team of researchers with members from the University of California and Rice University has found a way to get a flat transistor to defy theoretical limitations on Field Effect Transistors (FETs). In their paper published in the journal Nature, the team describes their work and why they believe it could lead to consumer devices that have both smaller electronics and longer battery life. Katsuhiro Tomioka with Erasmus MC University Medical Center in the Netherlands offers a News & Views article discussing the work done by the team in the same journal edition.

As Tomioka notes, the materials and type of architecture currently used in creating small consumer electronic devices is rapidly reaching a threshold upon which a tradeoff will have to be made—smaller transistors or more power requirements—this is because of the unique nature of FETs, shortening the channel they use requires more power, on a logarithmic scale. Thus, to continue making FETs ever smaller and to get them to use less power means two things, the first is that a different channel material must be found, one that allow high switch-on currents at low voltages. The second is a way must be found to lower the voltage required for the FETs.

Researchers have made inroads on the first requirement, building FETs with metal-oxide-semiconductor materials, for example. The second has proved to be more challenging. In this latest effort, the researchers looked to tunneling to reduce voltage demands, the results of which are called, quite naturally, tunneling FETs or TFETs—they require less voltage because they are covered (by a gate stack) and work by transporting a charge via quantum-tunneling. The device the team built is based on a 2D bilayer of molybdenum disulfide and bulk germanium—it demonstrated a negative differential resistance, a marker of tunneling, and a very steep subthreshold slope (the switching property associated with rapid turn-on) which fell below the classical theoretical limit.

The work by the team represents substantial progress in solving the miniturization problem for future electronics devices, but as the team notes, there is still much to do. They express optimism that further improvements will lead to not just better consumer devices, but tiny sensors that could be introduced into the body to help monitor health.

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Ultrafast Lasers Offer 3-D Micropatterning of Biocompatible Silk Hydrogels

Ultrafast Lasers Offer 3-D Micropatterning of Biocompatible Silk Hydrogels | Amazing Science |
Tufts University biomedical engineers are using low-energy, ultrafast laser technology to make high-resolution, 3-D structures in silk protein hydrogels. The laser-based micropatterning represents a new approach to customized engineering of tissue and biomedical implants.

The work is reported in a paper in PNAS Early Edition published September 15 online before print: "Laser-based three-dimensional multiscale micropatterning of biocompatible hydrogels for customized tissue engineering scaffolds."

Artificial tissue growth requires pores, or voids, to bring oxygen and nutrients to rapidly proliferating cells in the tissue scaffold.  Current patterning techniques allow for the production of random, micron-scale pores and the creation of channels that are hundreds of microns in diameter, but there is little in between.

The Tufts researchers used an ultrafast, femtosecond laser to generate scalable, high-resolution 3-D voids within silk protein hydrogel, a soft, transparent biomaterial that supports cell growth and allows cells to penetrate deep within it.  The researchers were able to create voids at multiple scales as small as 10 microns and as large at 400 microns over a large volume. 

Further, the exceptional clarity of the transparent silk gels enabled the laser's photons to be absorbed nearly 1 cm below the surface of the gel – more than 10 times deeper than with other materials, without damaging adjacent material. 

The laser treatment can be done while keeping the cell culture sealed and sterile. Unlike most 3-D printing, this technique does not require photoinitiators, compounds that promote photoreactivity but are typically bio-incompatible.  

"Because the femtosecond laser pulses allow us to target specific regions without any damage to the immediate surroundings, we can imagine using such micropatterning to controllably design around living cells, guide cell growth and create an artificial vasculature within an already densely seeded silk hydrogel," said senior author Fiorenzo G. Omenetto, Ph.D. Omenetto is associate dean for research, professor of biomedical engineering and Frank C. Doble professor at Tufts School of Engineering and also holds an appointment in physics in the School of Arts and Sciences.
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Self-assembling material that grows and changes shape could lead to artificial arteries

Self-assembling material that grows and changes shape could lead to artificial arteries | Amazing Science |
Researchers at QMUL have developed a way of assembling organic molecules into complex tubular tissue-like structures without the use of moulds or techniques like 3D printing.

The study, which will appear on Monday 28 September in the journal Nature Chemistry, describes how peptides and proteins can be used to create materials that exhibit dynamic behaviors found in biological tissues like growth, morphogenesis, and healing.

The method uses solutions of peptide and protein molecules that, upon touching each other, self-assemble to form a dynamic tissue at the point at which they meet. As the material assembles itself it can be easily guided to grow into complex shapes.

This discovery could lead to the engineering of tissues like veins, arteries, or even the blood-brain barrier, which would allow scientists to study diseases such as Alzheimer’s with a high level of similarity to the real tissue, which is currently impossible. The technique could also contribute to the creation of better implants, complex tissues, or more effective drug screening methods.

Alvaro Mata, Director of the Institute of Bioengineering at QMUL and lead author of the paper, said: “What is most exciting about this discovery is the possibility for us to use peptides and proteins as building-blocks of materials with the capacity to controllably grow or change shape, solely by self-assembly.

Karla Inostroza-Brito, PhD student and first author of the paper said: “The system is dynamic so it can be triggered on demand to enable self-assembly with a high degree of control, which allows the creation of complex shapes with a structure that resembles elements of native tissue.“

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NASA is developing the capabilities needed to send humans to an asteroid by 2025 and Mars in the 2030s

NASA is developing the capabilities needed to send humans to an asteroid by 2025 and Mars in the 2030s | Amazing Science |

NASA is developing the capabilities needed to send humans to an asteroid by 2025 and Mars in the 2030s – goals outlined in the bipartisan NASA Authorization Act of 2010 and in the U.S. National Space Policy, also issued in 2010.

Mars is a rich destination for scientific discovery and robotic and human exploration as mankind expands its presence into the solar system. Its formation and evolution are comparable to Earth, helping us to learn more about our own planet’s history and future. Mars had conditions suitable for life in its past. Future exploration could uncover evidence of life, answering one of the fundamental mysteries of the cosmos: Does life exist beyond Earth?

While robotic explorers have studied Mars for more than 40 years, NASA’s path for the human exploration of Mars begins in low-Earth orbit aboard the International Space Station. Astronauts on the orbiting laboratory are helping us prove many of the technologies and communications systems needed for human missions to deep space, including Mars. The space station also advances our understanding of how the body changes in space and how to protect astronaut health.

Our next step is deep space, where NASA will send a robotic mission to capture and redirect an asteroid to orbit the moon. Astronauts aboard the Orion spacecraft will explore the asteroid in the 2020s, returning to Earth with samples. This experience in human spaceflight beyond low-Earth orbit will help NASA test new systems and capabilities, such as Solar Electric Propulsion, which we’ll need to send cargo as part of human missions to Mars. Beginning in FY 2018, NASA’s powerful Space Launch System rocket will enable these “proving ground” missions to test new capabilities. Human missions to Mars will rely on Orion and an evolved version of SLS that will be the most powerful launch vehicle ever flown.

A fleet of robotic spacecraft and rovers already are on and around Mars, dramatically increasing our knowledge about the Red Planet and paving the way for future human explorers. The Mars Science Laboratory Curiosity rover measured radiation on the way to Mars and is sending back radiation data from the surface. This data will help us plan how to protect the astronauts who will explore Mars. Future missions like the Mars 2020 rover, seeking signs of past life, also will demonstrate new technologies that could help astronauts survive on Mars.

Engineers and scientists around the country are working hard to develop the technologies astronauts will use to one day live and work on Mars, and safely return home from the next giant leap for humanity. NASA also is a leader in a Global Exploration Roadmap, working with international partners and the U.S. commercial space industry on a coordinated expansion of human presence into the solar system, with human missions to the surface of Mars as the driving goal. Follow our progress at and

• NASA's Orion Flight Test and the Journey to Mars

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