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"Triple Point" Vanadium Dioxide Can Switch Between Insulator and Conductor 10 Trillion Times Per Second

"Triple Point" Vanadium Dioxide Can Switch Between Insulator and Conductor 10 Trillion Times Per Second | Amazing Science | Scoop.it

It is well known to scientists that the three common phases of water – ice, liquid and vapor – can exist stably together only at a particular temperature and pressure, called the triple point.

 

Also well known is that the solid form of many materials can have numerous phases, but it is difficult to pinpoint the temperature and pressure for the points at which three solid phases can coexist stably.

 

Scientists now have made the first-ever accurate determination of a solid-state triple point in a substance called vanadium dioxide, which is known for switching rapidly – in as little as one 10-trillionth of a second – from an electrical insulator to a conductor, and thus could be useful in various technologies.

 

“These solid-state triple points are fiendishly difficult to study, essentially because  the different shapes of the solid phases makes it hard for them to match up happily at their interfaces,” said David Cobden, a University of Washington physics professor.

 

“There are, in theory, many triple points hidden inside a solid, but they are very rarely probed.” Cobden is the lead author of a paper describing the work, published Aug. 22, 2013 in Nature. In 1959, researchers at Bell Laboratories discovered vanadium dioxide’s ability to rearrange electrons and shift from an insulator to a conductor, called a metal-insulator transition. Twenty years later it was discovered that there are two slightly different insulating phases.

 

The new research shows that those two insulating phases and the conducting phase in solid vanadium dioxide can coexist stably at 65 degrees Celsius, give or take a tenth of a degree (65 degrees C is equal to 149 degrees Fahrenheit).

 
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The largest fish that ever lived

The largest fish that ever lived | Amazing Science | Scoop.it

An international team of scientists has uncovered the remains of the world's largest fish. The 50ft Leedsichthys problematicus swam the oceans of the Jurassic era more than 160m years ago, sweeping up shoals of plankton through giant, mesh-covered gills. Leedsichthys was eventually wiped out by the same catastrophe that killed the dinosaurs 66m years ago.

 

The discovery by the team – led by Professor Jeff Liston of the National Museums of Scotland – is intriguing because it reveals that just as dinosaurs on land were going through major changes which saw the appearance of animals of vast dimensions – creatures that included Diplodocus, Apatosaurus and Brachiosaurus – reptiles in the sea had also started to grow to vast proportions in the Jurassic.

 

"The process is known as gigantism," said Liston. "It was known about in land animals at the time but we had no way of knowing if a parallel process occurred in the oceans. We now know that it did – though the reason for appearance of these gigantic beasts, both on land and in the water, is not clear at present."

 

Pieces of Leedsichthys fossils were first found by the British collector Alfred Leeds in 1889. Similar remains were subsequently found at other sites, from northern Germany to Normandy, Mexico and the Atacama desert in Chile. However, knowledge of the fish remained sketchy because of the poor quality of these finds. Leedsichthys had a skeleton that was mostly made of cartilage and which does not fossilise easily. This paucity of evidence and lack of clarity about its dimensions led to the fish being given its second name: problematicus.

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How To Print Wall-Sized Displays

How To Print Wall-Sized Displays | Amazing Science | Scoop.it
Researchers aim to print large areas of carbon nanotube thin-film transistors on plastic surfaces to make flexible displays and sensor networks.

 

Adapting conventional printing technology, researchers have developed a way to rapidly and inexpensively make uniform arrays of high-performing transistors out of carbon nanotubes on flexible plastic sheets. The process could eventually lead to a tool for manufacturing large-area, low-power sensor arrays and displays.

 

Thin-film transistors made from carbon nanotubes are attractive for these types of applications because they are robust and mechanically flexible, and they can be much more energy efficient than silicon transistors. They can also be applied as a solution, or “ink,” and can be processed at relatively low temperatures, making them compatible with plastic substrates.

 

Researchers using techniques more like those used in conventional integrated-circuit fabrication have previously made prototypes of nanotube transistor arrays on flexible plastic, including responsive sensor networks called “electronic skin”).

 

Carbon nanotube transistors have also been printed before, but their performance has lagged for one reason or another, says Ali Javey, a professor of electrical engineering and computer science at the University of California, Berkeley. Javey led the new work, which he says is the first demonstration of fully printed carbon nanotube transistor arrays that also consistently show very high performance—an important step toward roll-to-roll manufacturing of such devices.

 

Higher mobility makes the transistors more efficient and is crucial for displays, says Javey, because it means less voltage is required to supply the current necessary for running organic light-emitting diodes (OLEDs). The method his group has demonstrated “holds a lot of promise for very large-area displays—covering an entire wall with a display or a sensor array, for example,” he says. “If you are dealing with such large areas, in terms of manufacturing cost it’s just not feasible to use conventional-based processing.”

 

Javey uses a lab version of a well-known manufacturing process called gravure printing. In his setup, the plastic substrate is mounted to a cylindrical drum, which rolls it over a flat surface that serves as a mask, patterned with holes filled with inks made of the desired materials. In a roll-to-roll setup, a second roll would serve as the mask.

 

For now, Javey’s group will focus on refining this gravure method to further improve transistor performance and make the arrays more uniform. Eventually, the researchers hope to print more complicated integrated circuits that would include sensors and display components.

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Prehistoric Europeans spiced their food with garlic mustard at least 6,000 years ago

Prehistoric Europeans spiced their food with garlic mustard at least 6,000 years ago | Amazing Science | Scoop.it
Prehistoric Europeans were spicing up their food over 6,000 years ago with garlic mustard, according to a study of old pottery.

 

Researchers found evidence for garlic mustard in the residues left on ancient pottery shards discovered in what is now Denmark and Germany. The spice was found alongside fat residues from meat and fish.

 

The scientists make the case that garlic mustard contains little nutritional value and therefore must have been used to flavor the foods. "This is the earliest evidence, as far as I know, of spice use in this region in the Western Baltic; something that has basically no nutritional value, but has this value in a taste sense," said Dr Hayley Saul, who led the study from the University of York, UK.

 

The researchers looked at charred deposits found on the inside of pottery shards that had been dated to between 5,800 and 6,150 years ago.

 

These deposits contained microscopic traces of plant-based silica, known as phytoliths, which can be used to identify the plants from which they came.

It was these phytoliths that provided the evidence of garlic mustard (Alliaria petiolata) in the carbonised scrapings.

 

The team found more phytoliths from residues taken from the inside of pots than from the outside, which they say shows that these were the direct result of culinary practice.

 

The implications from these findings challenge the previously held belief that hunter-gatherers were simply concerned with searching for calorific food. Dr Saul believes these latest results point to something much more like cuisine.

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Scientists Capture Rare Photographs of Red Lightning

Scientists Capture Rare Photographs of Red Lightning | Amazing Science | Scoop.it

Sprites, also known as red lightning, are electrical discharges that appear as bursts of red light above clouds during thunderstorms.Because the weather phenomenon is so fleeting (sprites flash for just milliseconds) and for the most part not visible from the ground, they are difficult to observe and even more difficult to photograph, rather like the mischievous air spirits of the fantasy realm that they’re named for. Ahrns and his colleagues, however, have captured extremely rare photographs of the red lightning, using DSLR cameras and high speed video cameras positioned in the plane’s window. The researchers hope to learn more about the physical and chemical processes that give rise to sprites and other forms of upper atmospheric lightning.

 

What’s it like to capture images of some of nature’s most short-lived and erratic features? I questioned Ahrns over email, and he explained what sprites are, why they occur, how scientists find them and why he’s so interested in the elusive phenomena.


A sprite is a kind of upper atmosphere electrical discharge associated with thunderstorms. A large electric field, generated by some lightning strokes, ionizes the air high above the cloud, which then emits the light we see in the pictures. They obviously beg comparison to the regular lightning bolts we see all the time, but I like to point out that the sprites are much higher, with the tops reaching up to around 100 kilometers, and higher. A lightning bolt might stretch around 10 kilometers from the cloud to the ground, but a sprite can reach 50 kilometers tall.

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Most strains of gut microbes stay with us for decades, which may prove useful for tracking our health

Most strains of gut microbes stay with us for decades, which may prove useful for tracking our health | Amazing Science | Scoop.it

We all have trillions of microbes inside our guts, which outnumber our own cells by a factor of 10. Now, a team from Washington University School of Medicine in St. Louis (WUSTL) has shown that this microscopic community is extraordinarily stable. In healthy people, once these microbes are established in the gut early in life, presumably due to contact from close family members, most strains are unwavering in their presence, staying in the gut for decades or longer.

 

“We have this part of ourselves that’s assembled from outside but stays inside for decades and decades, and it contributes to our uniqueness as individuals and our health,” said WUSTL’s Jeffrey Gordon who led the study.

Although the team only studied healthy adults, their results have big implications for our understanding of disease, Gordon added. Many studies have shown that conditions such as obesity or autoimmune disorders are associated with dramatic changes in the gut microbiota.  But, Gordon said, “if we don’t know what the normal variations are in healthy people, we can’t tell how an individual with disease deviates.”

 

If these communities are usually steady, it may be possible to monitor a person’s health by analyzing stool samples each year, said Jacques Ravel, a microbiologist from the University of Maryland School of Medicine who was not involved in the study. “This is the future of medicine: a genome once and a microbiome at each annual exam.”

 

While other studies have tracked changes in the gut microbiota over time, Gordon’s team wanted to get a more detailed picture. “In the past, people have gone down to the species level,” said former postdoc Jeremiah Faith, now at the Icahn School of Medicine at Mount Sinai. “But everyone has E. coli in their guts for sure. The difference between those E. coli strains can be pretty big,”

 

Current techniques have such a high error rate that it can be unclear if a variation in sequence is due to the presence of a new strain or a mistake in the sequencing. Faith surmounted this problem by developing a new technique called LEA-Seq (low-error amplicon sequencing). It tags a small fraction of the DNA fragments within a sample and makes exponentially more copies of them than traditional sequencing methods, so that each can be sequenced many times over greatly improving the accuracy of the resulting sequences.

 

Two years ago, Faith first tested his new technique on stool samples collected from a single volunteer on multiple occasions. “I was completely floored,” he said. “Over the course of 3 months, they had virtually identical sets of microbes.” This pattern held when he looked at 175 stool samples, taken from 37 healthy US adults over 5 years. 

 

On average, each volunteer harboured around 200 strains representing 100 different bacterial species. More than 70 percent of these stayed the same after a year, and 60 percent remained across the entire 5-year span. “If you extrapolate from the rate of change, it looks like the strains we harbor in our guts last decades or maybe a lifespan,” said Gordon.

 

The team also found that people share gut microbe strains with relatives, but not unrelated people. This suggests that family members, through touching each other or sharing the same environments, are colonized by the same microbes during their early years. “There’s an early period of assembly for the gut microbe community, and your physiology as an adult is likely a legacy of this event,” said Gordon.

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The man who hears events before he sees them

The man who hears events before he sees them | Amazing Science | Scoop.it

PH is the first case of a person who hears speech before seeing a speaker's lips move. His badly dubbed world reveals timing mechanisms in the brain.

 

"I was staying with my daughter and they like to have the television on in their house. I turned to my daughter and said 'you ought to get a decent telly, one where the sound and programme are synchronised'. I gave a little chuckle. But they said 'there's nothing wrong with the TV'." Puzzled, he went to the kitchen to make a cup of tea. "They've got another telly up on the wall and it was the same. I went into the lounge and I said to her 'hey you've got two TVs that need sorting!'." That was when he started to notice that his daughter's speech was out of time with her lip movements too. "It wasn't the TV, it was me. It was happening in real life."

 

PH is the first confirmed case of someone who hears people speak before registering the movement of their lips. His situation is giving unique insights into how our brains unify what we hear and see. It's unclear why PH's problem started when it did – but it may have had something to do with having acute pericarditis, inflammation of the sac around the heart, or the surgery he had to treat it.

 

Brain scans after the timing problems appeared showed two lesions in areas thought to play a role in hearing, timing and movement. "Where these came from is anyone's guess," says PH. "They may have been there all my life or as a result of being in intensive care."

 

Several weeks later, PH realised that it wasn't just other people who were out of sync: when he spoke, he registered his words before he felt his jaw make the movement. "It felt like a significant delay, it sort of snuck up on me. It was very disconcerting. At the time I didn't know whether the delay was going to get bigger, but it seems to have stuck at about a quarter of a second."

 

Light and sound travel at different speeds, so when someone speaks, visual and auditory inputs arrive at our eyes and ears at different times. The signals are then processed at different rates in the brain. Despite this, we normally perceive the events as happening simultaneously – but how the brain achieves this is unclear.

 

To investigate PH's situation, Elliot Freeman at City University London and colleagues performed a temporal order judgement test. PH was shown clips of people talking and was asked whether the voice came before or after the lip movements. Sure enough, he said it came before, and to perceive them as synchronous the team had to play the voice about 200 milliseconds later than the lip movements.

 

The team then carried out a second, more objective test based on the McGurk illusion. This involves listening to one syllable while watching someone mouth another; the combination makes you perceive a third syllable.

 

Since PH hears people speaking before he sees their lips move, the team expected the illusion to work when they delayed the voice. So they were surprised to get the opposite result: presenting the voice 200 ms earlier than the lip movements triggered the illusion, suggesting that his brain was processing the sight before the sound in this particular task.

 

And it wasn't only PH who gave these results. When 37 others were tested on both tasks, many showed a similar pattern, though none of the mismatches were noticeable in everyday life.

 
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Mysterious Giant Crater-like Structures Found near New-Zealand

Mysterious Giant Crater-like Structures Found near New-Zealand | Amazing Science | Scoop.it

Three giant pockmarks – crater-like structures on the seabed – found by the team are possibly twice the size of the largest pockmarks ever recorded.

 

Scientists believe they are the ancient remnants of vigorous degassing from under the seafloor into the ocean. The structures (the largest being 6.8 miles by 3.7 miles in diameter and 328 feet deep) are at water depths of about 0.6 miles and there is currently no sign of gas being emitted from them.

 

The team investigated the larger seafloor structures on the German research ship Sonne. Their aim was to determine the geological origin of the structures, which were first noted in 2007.

“Some of the pockmarks are huge compared to similar structures observed elsewhere in the world,” Dr Davy said. “It’s most unusual for scientists to encounter seafloor structures of this size and complexity. They are big enough to enclose the Wellington city urban area, or lower Manhattan.”

 

The geological processes that led to the formation of the larger structures were still unclear.

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New theory points to ‘zombie vortices’ as key step in star formation

New theory points to ‘zombie vortices’ as key step in star formation | Amazing Science | Scoop.it
UC Berkeley scientists have proposed a new model that elucidates a key step in star formation. They point to "zombie vortices" as a destabilizing force needed to help protostars accumulate the mass needed to grow into stars.

 

A previously unknown instability creates space-filling lattices of 3D vortices in linearly stable, rotating, stratified shear flows. The instability starts from an easily excited critical layer. The layer intensifies by drawing energy from the background shear and rolls up into vortices that excite new critical layers and vortices. The vortices self-similarly replicate to create lattices of turbulent vortices. The vortices persist for all time. This self-replication occurs in stratified Couette flows and in the dead zones of protoplanetary disks where it can destabilize Keplerian flows.

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Nicotine exposure in the womb gives baby rats addictive personalities

Nicotine exposure in the womb gives baby rats addictive personalities | Amazing Science | Scoop.it
Results suggest explanation for why people exposed to nicotine in the womb are more likely to become smokers. 

 

Exposure to nicotine in the womb increases the production of brain cells that stimulate appetite, leading to overconsumption of nicotine, alcohol and fatty foods in later life, according to a new study in rats.

 

Smoking during pregnancy is known to alter fetal brain development and increase the risk of premature birth, low birth weight and miscarriage. Prenatal exposure to nicotine also increases the likelihood of tobacco use and nicotine addiction in later life, but exactly how is unclear. To understand the mechanisms behind this effect, Sarah Leibowitz, a behavioural neurobiologist at the Rockefeller University in New York, and her colleagues injected pregnant rats with small doses of nicotine — which the researchers say are comparable to the amount a pregnant woman would get from smoking one cigarette a day — and then examined the brains and behaviour of the offspring. 

 

In a paper published recently in the Journal of Neuroscience, they found that nicotine increased the production of specific types of neurons in the amygdala and hypothalamus. These cells produce orexin, enkephalin and melanin-concentrating hormone, neuropeptides that stimulate appetite and increase food intake.

 

Rats exposed to nicotine in the womb had more of these cells and produced more of the neuropeptides than those that were not, and this had long-term consequences on their behaviour. As adolescents, they not only self-administered more nicotine, but also ate more fat-rich food and drank more alcohol.

 

“These peptide systems stimulate food intake,” says Leibowitz, “but we found that they similarly increase the consumption of drugs and stimulate the brain’s reward mechanisms that promote addiction and substance abuse.”

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New drug mimics the beneficial effects of exercise -- at least in mice

New drug mimics the beneficial effects of exercise -- at least in mice | Amazing Science | Scoop.it

A drug known as SR9009, which is currently under development at The Scripps Research Institute (TSRI), increases the level of metabolic activity in skeletal muscles of mice. Treated mice become lean, develop larger muscles and can run much longer distances simply by taking SR9009, which mimics the effects of aerobic exercise. If similar effects can be obtained in people, the reversal of obesity, metabolic syndrome, and perhaps Type-II diabetes might be the very welcome result.

 

The drug was developed by Professor Thomas Burris of TSRI, who found that it was able to reduce obesity in populations of mice. It binds to and activates a protein called Rev-ErbAα, which influences fat and sugar burning in the liver, production of fat cells, and the body's inflammatory response.

 

Previous studies on mice lacking Rev-ErbAα showed decreased skeletal muscles, metabolic rate, and running capacity. Such mice appeared fated by their genetics to live as couch potatoes.

 

When Burris' group administered SR9009 to these mice to activate the Rev-Erbα protein, the results were remarkable. The metabolic rate in the skeletal muscles of the mice increased significantly. The treated mice were not allowed to exercise, but despite this they developed the ability to run about 50 percent further before being stopped by exhaustion.

 

“The animals actually get muscles like an athlete who has been training,” said Burris. “The pattern of gene expression after treatment with SR9009 is that of an oxidative-type muscle – again, just like an athlete.”

 

Burris noted that the beneficial effects of SR9009 on mice could carry over to people with metabolic syndrome or other conditions that reduce their ability to exercise.

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Tools for crushing diatoms – opal teeth in copepods feature a rubber-like bearing composed of resilin

Tools for crushing diatoms – opal teeth in copepods feature a rubber-like bearing composed of resilin | Amazing Science | Scoop.it

Copepods dominate the zooplankton in nearly all areas of the World Ocean and thus play a significant role in the pelagic food web. Many copepod species feed mainly on phytoplankton and are important links between the primary producers and organisms of higher trophic levels. Accordingly, the knowledge of the impact of copepod grazing on phytoplankton stocks is essential for the understanding of particle and energy fluxes in the ocean.


Diatoms are generally known for superior mechanical properties of their mineralised shells. Nevertheless, many copepod crustaceans are able to crush such shells using their mandibles. This ability very likely requires feeding tools with specific material compositions and properties. For mandibles of several copepod species silica-containing parts called opal teeth have been described. The present study reveals the existence of complex composite structures, which contain, in addition to silica, the soft and elastic protein resilin and form opal teeth with a rubber-like bearing in the mandibles of the copepod Centropages hamatus. These composite structures likely increase the efficiency of the opal teeth while simultaneously reducing the risk of mechanical damage. They are supposed to have coevolved with the diatom shells in the evolutionary arms race, and their development might have been the basis for the dominance of the copepods within today's marine zooplankton.

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Black Holes and Gravitational Waves: Movies of Extreme Spacetimes

Black Holes and Gravitational Waves: Movies of Extreme Spacetimes | Amazing Science | Scoop.it

A beginner's guide to black holes, warped spacetime, gravitational waves, and other bizarre ideas from astrophysics: From Galileo's first telescope to today's most sensitive neutrino telescopes, astronomers have been developing new eyes with which to see the night sky, allowing them to discover new worlds while better understanding our own. Now, for the first time, astronomers are creating new earswith which to hear the Universe around us.


The sounds we hear in our ears are carried through the air around us. Anything giving off sound gives the air more pressure, then less pressure. These changes in pressure travel as waves, until they reach our ears and push on our eardrums. The waves don't move our heads very much, but they move our eardrums, which allows the delicate mechanisms in our ears to pick up these movements relative to our heads.

Since sound needs air (or some other matter) to compress, sound can't travel through empty space. Gravitational waves, on the other hand, don't need air to travel; they just need spacetime. They travel across the Universe from its deepest reaches, never stopping or slowing down—regardless of the presence or absence of air. Nonetheless, they have a similar effect on our ears. As a gravitational wave passes through your head, the positions of your eardrums change relative to the position of your head. Again, the delicate mechanisms in your ears would pick up these movements, and your brain would turn them into sounds. But why aren't we kept up at night with the noise from black holes everywhere falling into each other?

It turns out that, by the time gravitational waves from these distant sources reach us, they are incredibly quiet. The smallest sound that a human with good ears can hear is roughly the sound of a mosquito buzzing 10 feet away. Gravitational waves reaching the Earth are typically another three trillion times quieter than this. To put it another way, consider the sound of an atomic blast 20 feet away. That sound (though you wouldn't be around to hear it if you were there) is as much louder than the mosquito as gravitational waves are quieter.

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New research suggests that 'female-generated sperm' and 'male eggs' are possible

New research suggests that 'female-generated sperm' and 'male eggs' are possible | Amazing Science | Scoop.it

New research from Japan has suggested that it may be possible in the future for scientists to grow male and female reproductive cells from the opposite gender. In other words, to create sperm from women and eggs from men. Japanese researchers use skin cells from mice to create sperm and eggs that were later used to create a live birth.

 

Katsuhiko Hayashi of Kyoto University in Japan has published research in which skin cells from mice were used to create primordial germ cells or PGCs. These cells, the common precursor of both male and female sex cells, were then developed into both sperm and eggs. Using these live-births were created via in vitro fertilisation.

 

Although the techniques involved are still in their infancy, the possibilities for reproductive medicine are startling. Not only could the research of Hayashi and his senior professor Mitinori Saitou allow infertile women to have babies by creating eggs from their skin cells, but it might make it possible for sperm and eggs cells to be created from either males or females.

 

The process begins by extracting pluripotent stem cells from early-stage embryos and somatic cells, and then converting these into PGCs using ‘signalling molecules’. These germ cells were transplanted into the ovaries and testes of living mice to develop. Once these cells were mature they were extracted and used to fertilise one another in vitro.

 
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Keisha Lewis's curator insight, August 27, 2013 7:10 AM

Great for a reproduction lesson.

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Micro black holes could form at lower-than-expected energies

Micro black holes could form at lower-than-expected energies | Amazing Science | Scoop.it

Colliding particles act like gravitational lenses and focus energy to form a single black hole. New simulations of head-on collisions of particles travelling at nearly the speed of light show that black-hole formation can occur at lower collision energies than expected, according to a team of researchers in the US. The researchers attribute this to a "gravitational focusing effect" whereby the two colliding particles act like gravitational lenses, focusing the energy of the collision into two distinct light-trapping regions that eventually collapse into a single black hole. Although the work shows that black holes can form at lower collision energies than expected, the team says that the result has no impact on real particle collisions taking place at the Large Hadron Collider (LHC) at CERN.

 

Frans Pretorius and William East of Princeton University in the US want to better understand the dynamics of particle collisions at the super-Planck scale. Planck units are a system of units comprised of the simplest algebraic combinations of the fundamental constants of nature – the speed of light c, Newton's constant G, Planck's constant h and so on. For example, a combination of the constants to form a unit of Planck energy (Ep) is about 2 × 10^9 J. Pretorius explains that a super-Planck-scale collision is a collision between two fundamental particles where the total energy (rest energy (Er) plus the kinetic energy) exceeds Ep. At the Planck scale, quantum-gravity effects are expected to start playing a role in the interaction. However, at energies greater than Ep (and no-one knows exactly how much greater), classical gravity dominates the interaction.

 

So the researchers wanted a completely classical calculation, and this, explains Pretorius, is the "crucial ingredient in the argument that super-Planck-scale collisions form black holes, regardless of any non-gravitational interactions between the particles". He goes on to explain that this is important, as currently we do not know exactly what quantum-gravity interactions occur at the Planck scale. According to Pretorius, the new results suggest that for energies sufficiently above the Planck scale it does not matter – a black hole will form around the interaction, hiding all quantum effects, at least temporarily.

 

While considering the super-Planck-scale regime, the researchers look at specific "gamma" (γ) values in the collisions. Pretorius explains to physicsworld.com that γ is a measure of the kinetic energy of the interaction; that is, if the rest energy of one of the colliding particles of mass m is Er = mc^2, then the total energy of the particle in motion is Et = γ × Er. So, when two particles of massm collide, each moving with velocity v towards each other in the reference frame of the lab, the total energy of the collision is 2 × γ × Er.

 

According to the researchers, the critical γ depends on the particular model of a particle, and in their simulations, the particles of choice are "fluid stars" – a hypothetical and perfect "star" or particle that Pretorius describes as a "classical model of a fermionic star". They used the fluid star because its γ value is high enough that the total collision energy would allow for a black hole to form. "Since our calculation is purely classical, so no h, this serves as the proxy of the Planck energy," says Pretorius.

 

A previous estimate for black-hole formation – known as the "Hoop Conjecture" and developed by Kip Thorne in 1994 – says that an object compressed in a highly spherical manner will "form a black hole around itself when and only when its circumference in all directions becomes less than the critical circumference". This "critical circumference" is directly related to the Schwarzschild radius (rs) of the object. But in the case of their collisions with super-Planck-scale fluid stars, Pretorius and East found that black-hole formation "actually begins at a fraction of about one-third of this [Hoop Conjecture estimate] energy".

 

Pretorius and East are clear that their simulation results have no real bearing on safety issues at any high-energy experiments. They say that even if such black holes are formed, they would still be completely benign given what we know about them. According to the team, the results might give researchers a better idea of the energies at which black holes might start to form. "Though the key question is what the true Planck scale is," muses Pretorius. The units he mentioned above suggest that the Planck energy is 10^16 TeV in LHC-like terms, so about 15 orders of magnitude above LHC energies. If this is the case, it is not even remotely possible for the LHC to form black holes, even with the factor of one-third decrease in the threshold energy. "However, if there are extra, small dimensions, as string theory predicts, then the true Planck scale could be lower. There are no firm predictions on how much lower, so this is a highly speculative scenario. If black holes were formed, it would strongly indicate that there are extra dimensions, which would be a very profound discovery," says Pretorius.

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How to reconstruct from brain images what a person was reading

How to reconstruct from brain images what  a person was reading | Amazing Science | Scoop.it

Researchers from Radboud University Nijmegen in the Netherlands have succeeded in determining which letter a test subject was looking at. They did that by analyzing the corresponding functional magnetic resonance imaging (fMRI) scanned images of activity in the visual cortex of the brain, using a linear Gaussian mathematical model.

 

The researchers “taught” the model how 1200 voxels (volumetric pixels) of 2x2x2 mm from the brain scans correspond to individual pixels in different versions of handwritten letters. By combining all the information about the pixels from the voxels, it became possible to reconstruct a rough version of the image viewed by the subject. The result was a fuzzy speckle pattern.


They then taught the model what letters actually look like. “This improved the recognition of the letters enormously,” said lead researcher Marcel van Gerven. “The model compares the letters to determine which one corresponds most exactly with the speckle image, and then pushes the results of the image towards that letter.”

 

The result was close resemblance to the actual letter, a true reconstruction.

“Our approach is similar to how we believe the brain itself combines prior knowledge with sensory information. For example, you can recognize the lines and curves in this article as letters only after you have learned to read. And this is exactly what we are looking for: models that show what is happening in the brain in a realistic fashion.

 

:We hope to improve the models to such an extent that we can also apply them to the working memory or to subjective experiences such as dreams or visualizations. Reconstructions indicate whether the model you have created approaches reality.”

 

“In our further research we will be working with a more powerful MRI scanner,” said Sanne Schoenmakers, who is working on a thesis about decoding thoughts. “Due to the higher resolution of the scanner, we hope to be able to link the model to more detailed images. We are currently linking images of letters to 1200 voxels in the brain; with the more powerful scanner we will link images of faces to 15,000 voxels.”

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Sharpest Views of the Cosmos Ever

Sharpest Views of the Cosmos Ever | Amazing Science | Scoop.it
Astronomers have built a new astro-camera that, when fitted onto the largest observatories on Earth, can snap photos of the universe twice as sharp as the famed Hubble Space Telescope.

 

The Magellan Telescope with MagAO’s Adaptive Secondary Mirror (ASM) mounted at the top looking down some 30 feet onto the 21-foot diameter primary mirror, which is encased inside the blue mirror cell.

 

The power of visible light adaptive optics: On the left is a “normal” photo of the theta 1 Ori C binary star in red light. The middle image shows the same object, but with MagAO’s adaptive optics system turned on. Eliminating the atmospheric blurring, the resulting photo becomes about 17 times sharper, turning a blob into a crisp image of a binary star pair. These are the highest resolution photos taken by a telescope.

 

“I have been imaging Theta 1 Ori C for more than 20 years and never could directly see that it was in fact two stars,” Close said. “But as soon as we turned on the MagAO system, it was beautifully split into two stars.”

 

The new photos also reveal surprising details of dust formations associated with the beginnings of planetary systems around the stars. Never-before-seen teardrop shaped clouds carved by strong radiation winds emitted from the baby stars.

 

“It is important to understand how dust is laid out in these objects because that dust and gas is what nature uses to build planets,” Close explained. “Our new imaging capabilities revealed there is very little dust and gas in the outer part of the disk.”

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WIRED: Vanish from the Internet With This One-Stop Website - justdelete.me

WIRED: Vanish from the Internet With This One-Stop Website - justdelete.me | Amazing Science | Scoop.it

Even if you’re not Edward Snowden, there are times when excising your social media presence is necessary. Companies usually don’t make it easy, though, often hiding the delete button inside myriad confusing menus and settings. Save some time and bookmark justdelete.me, a new page that collects direct links for killing various accounts dead and puts them all on one, easy-to-use page.

 

Justdelete.me is an excellent resource and evidently quite a bit of work went into it. For instance, for Facebook, the link goes directly to the delete button (no “deactivation” shenanigans here.) But not all accounts are as simple: Sometimes you’ve got to contact customer service, or, like Netflix, they’ll cancel your account but won’t delete your data. Even here justdelete.me excels, linking to the relevant help pages and contact forms.

 

Give Robb Lewis the good Netizen of the month award. Although most competent computer users could eventually find all these various methods to delete online accounts, it’s quite a bit faster (and less frustrating) when they’re all on one page. He even put the source for justdelete.me on Github too — so if he loses interest or the various social media companies change their policies, this killer idea can live on.

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Dolphins and whales flee from military sonar leading to mass strandings

Dolphins and whales flee from military sonar leading to mass strandings | Amazing Science | Scoop.it

Whales flee from the loud military sonar used by navies to hunt submarines, new research has proven for the first time. The studies provide a missing link in the puzzle that has connected naval exercises around the world to unusual mass strandings of whales and dolphins.

 

Beaked whales, the most common casualty of the strandings, wereshown to be highly sensitive to sonar. But the research also revealed unexpectedly that blue whales, the largest animals on Earth and whose population has plummeted by 95% in the last century, also abandoned feeding and swam rapidly away from sonar noise.

 

The strong response observed in the beaked whales occurred at noise levels well below those allowed for US navy exercises. "This result has to be taken into consideration by regulators and those planning naval exercises," said Stacy DeRuiter, at the University of St Andrews in Scotland, who led one of the teams.

 

"For whales and dolphins, listening is as important as seeing is for humans – they communicate, locate food, and navigate using sound," said Sarah Dolman, at charity Whale and Dolphin Conservation. "Noise pollution threatens vulnerable populations, driving them away from areas important to their survival, and at worst injuring or even causing the deaths of some whales and dolphins." Dolman said there were no accepted international standards regarding noise pollution and there was an urgent need to re-evaluate the environmental impacts of military activities.

 

The US Navy part-funded the new studies but said the findings only showed behavioural responses to sonar, not actual harm. Nonetheless, Kenneth Hess, a US Navy spokesman, said permit conditions for naval exercises were reviewed annually and added: "We will evaluate the effectiveness of our marine mammal protective measures in light of new research findings."

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The last survivors of the end of the world

The last survivors of the end of the world | Amazing Science | Scoop.it

In 2 billion years' time, life on Earth will be confined to pockets of liquid water deep underground, according to PhD astrobiologist Jack O'Malley James of the University of St Andrews. The new research also suggests that though the hardiest forms of life may have a foothold on similar worlds in orbit around other stars, evidence for it may be very subtle. O' Malley- James will present the findings at the National Astronomy Meeting in St Andrews, Scotland.

All species have finite lifetimes, with each eventually facing an event that leads to its extinction. This can be sudden and catastrophic, like the giant impact that wiped out the dinosaurs, or a slow and gradual process. Ultimately, a combination of slow and rapid environmental changes will result in the extinction of all species on Earth, with the last inhabitants disappearing within 2.8 billion years from now.

The main driver for these changes will be the Sun. As it ages over the next few billion years, the Sun will remain stable but become steadily more luminous, increasing the intensity of its heat felt on Earth and warming the planet to such an extent that the oceans evaporate. In his new work, O'Malley James has created a computer model to simulate these extremely long-range temperature forecasts and has used the results to predict the timeline of future extinctions.

Within the next billion years, increased evaporation rates and chemical reactions with rainwater will draw more and more carbon dioxide from the Earth's atmosphere. The falling levels of CO2 will lead to the disappearance of plants and animals and our home planet will become a world of microbes. At the same time the Earth will be depleted of oxygen and will be drying out as the rising temperatures lead to the evaporation of the oceans. A billion years after that the oceans will have gone completely.

"The far-future Earth will be very hostile to life by this point", said O'Malley-James. "All living things require liquid water, so any remaining life will be restricted to pockets of liquid water, perhaps at cooler, higher altitudes or in caves or underground". This life will need to cope with many extremes like high temperatures and intense ultraviolet radiation and only a few microbial species known on Earth today could cope with this.

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Birds are aware of speed limits on roads

Birds are aware of speed limits on roads | Amazing Science | Scoop.it

Birds take off farther from an approaching car on a faster road than on a slower one – regardless of the car's speed – suggesting they know.

 

Birds cannot read road signs, but they know that some roads have higher speed limits than others. They will take off further away from an approaching car on a faster road than on a slower road – regardless of the speed of the car.

 

When Pierre Legagneux of the University of Quebec at Rimouski and Simon Ducatez of McGill University in Montreal, both in Canada, were working together in France in 2006, they began studying the birds they encountered on the drive home from the lab.

 

They found that where there was a 50-kilometre-per-hour speed limit, birds on the road typically took off when the car was about 15 metres away, whereas on a 110-km-per-hour road, they took off when a car was nearer 75 metres away. They did this even when faced with a car travelling faster on the slow road or slower on the fast road.

 

"What was really cool is that birds did not respond to the speed of the car but rather to the speed limit of the road section," says Legagneux. "It was like they were able to read road signs – although they obviously do not."

 

The researchers think the birds treat cars as predators, and realise that in some parts of their environment the predators are more dangerous than in others.

 

The two biologists also discovered that the distance at which the birds took off varied according to season. They let cars get closer in the spring, and behaved more cautiously in autumn. Legagneux and Ducatez think that this is either because birds are more active in the spring feeding their children, or that juvenile birds are first learning about roads then and have less experience with cars.

 

"Birds are able to associate environments, like forests or roads, with risk," says Christopher Lepczyk, an ornithologist at the University of Hawaii, Manoa. He thinks the work could prompt follow-up studies comparing birds in urban and rural areas, and perhaps encourage more innovative methods. "I just think it's really cool," he says. "We don't do enough of this kind of work."

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New kind of hologram creates strange state of light at visible and invisible wavelengths

New kind of hologram creates strange state of light at visible and invisible wavelengths | Amazing Science | Scoop.it

Applied physicists at the Harvard School of Engineering and Applied Sciences (SEAS) have demonstrated that they can change the intensity, phase, and polarization of light rays using a hologram-like design decorated with nanoscale structures.

 

As a proof of principle, the researchers have used it to create an unusual state of light called a radially polarized beam, which—because it can be focused very tightly—is important for applications like high-resolution lithography and for trapping and manipulating tiny particles like viruses.

 

This is the first time a single, simple device has been designed to control these three major properties of light at once. (Phase describes how two waves interfere to either strengthen or cancel each other, depending on how their crests and troughs overlap; polarization describes the direction of light vibrations; and the intensity is the brightness.)

 

“Our lab works on using nanotechnology to play with light,” says Patrice Genevet, a research associate at Harvard SEAS and co-lead author of a paper published this month in Nano Letters. “In this research, we’ve used holography in a novel way, incorporating cutting-edge nanotechnology in the form of subwavelength structures at a scale of just tens of nanometers.” One nanometer equals one billionth of a meter.

 

Genevet works in the laboratory of Federico Capasso, Robert L. Wallace Professor of Applied Physics and Vinton Hayes Senior Research Fellow in Electrical Engineering at Harvard SEAS. Capasso’s research group in recent years has focused on nanophotonics—the manipulation of light at the nanometer scale—with the goal of creating new light beams and special effects that arise from the interaction of light with nanostructured materials.

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Hydractinia echinata has the power to regenerate any lost body part, can clone itself and does not age

Hydractinia echinata has the power to regenerate any lost body part, can clone itself and does not age | Amazing Science | Scoop.it

A small, native-Irish marine animal with remarkable powers of regeneration has provided stem cell scientists studying congenital defects and cancer biology with significant new leads.

 

Hydractinia echinata has the power to regenerate any lost body part, can clone itself, does not age biologically, and, according to Dr Uri Frank, who is leading the research at NUI Galway’s regenerative medicine institute, “in theory - lives forever”.

 

The tiny creature, which is a relative of jellyfish and sea anemones, is “perfect for understanding the role of stem cells in development, ageing and disease,” says Dr Frank.

 

“Hydractinia has some stem cells which remain at an embryonic-like stage throughout its life. It sounds gruesome, but if it has its head bitten off, it simply grows another one within a few days using its embryonic or ‘pluripotent’ stem cells”, explains Frank. “So the potential for research is immense”, he adds.

 

The Galway team has discovered an unknown link between ‘heat-shock’ proteins and a cell-signalling pathway, known as Wnt signalling, in Hydractinia stem cells. “These two cellular signalling mechanisms are known to play important roles in development and disease, so they have been widely, though separately, studied. We have shown that they talk to each other, providing a new perspective for all scientists in this field,” says Dr Frank. “We found the link coincidentally - we weren’t looking for it.”

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1,000 mile wide magnetic super tornadoes rage on the Sun

1,000 mile wide magnetic super tornadoes rage on the Sun | Amazing Science | Scoop.it

The discovery of "super-tornadoes" rising above the surface of the sun may help solve the mystery of how our home star heats it wispy outer atmosphere to a million degrees. There is plenty of energy below the 5780° visible surface to do the job, but solar physicists have long argued about how that energy heats the corona, seen as an encircling crown of light that emerges during a total solar eclipse. Now a group reports online today in Nature that, using both spaceborne and ground-based telescopes, it has detected 1500-kilometer-wide swirls of solar atmosphere rising from the surface into the corona.

 

Each lasts 10 to 15 minutes, and there are about 11,000 of them on the sun at a time. Computer simulations (picture) show how similar-looking the twisting magnetic field lines of a solar tornado are to real tornadoes. Now solar physicists must figure out how much energy super-tornadoes deliver compared with other proposed energy sources.

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Jim Doyle's curator insight, August 21, 2013 6:19 AM

That is what you call a storm

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Cisco’s Forecast: 50 Billion Internet-Connected Devices by 2020 -- Too Conservative?

Cisco’s Forecast: 50 Billion Internet-Connected Devices by 2020 -- Too Conservative? | Amazing Science | Scoop.it
As a tech memes go, the Internet of Things is getting a bit long in tooth. The idea of internet-connected smart stuff has been heralded for years now. But where exactly are we in the quest to connect all things?

 

According to Cisco, there are an estimated 1.5 trillion things in the world (no mention of exactly how they counted those things, but let’s go with it) and approximately 8.7 billion, or 0.6%, were connected in 2012. The firm expects a 25% annualized decrease in price to connect between 2012 and 2020 and a matching 25% annualized increase in connectivity. That means we can expect 50 billion connected things by 2020, with 50% of those connections happening in the final three years of the decade.

 

Fifty billion sounds like a big number, but one could argue Cisco’s forecast is pretty conservative. Of their estimated 1.8 trillion total things in 2020, 50 billion would be a mere 2.7% of the total. Yes, it’s an increase from 2012′s 0.6%—but a fairly modest increase as these things go. Cisco is a big company, and it pays to be careful.

 

Maybe we can go out on a limb where Cisco can’t. The firm bases its projected annualized growth rate primarily on the decreasing price to connect. But there are other drivers too—the declining price and increasing power of embedded chips, for example. Or rapidly improving “big data” software that makes all that new information useful, and therefore more highly demanded.

 

In a world of exponential technology, things can move faster than our linear brains can fathom. If the number of connected things grew at twice Cisco’s predicted annualized rate, we’d have 223 billion connected things, or 12% of the total, by 2020. At a little less than quadruple Cisco’s forecast, we’d be talking 1.5 trillion connected things, or 82% of the total, by the end of the decade.

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