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Scooped by Dr. Stefan Gruenwald!

Amazon Rainforest is ‘at Higher Risk of Tree Loss’ than ever before due to Global Warming

Amazon Rainforest is ‘at Higher Risk of Tree Loss’ than ever before due to Global Warming | Amazing Science |
Part of the Amazon rainforest may be more vulnerable to the effects of climate change than first thought, say researchers.


Findings showed that since 1979, the dry season lasted about a week longer in each decade. At the same time, the annual fire seasons have become longer. The most likely explanation for the increasingly longer dry seasons is global warming.

If the damage is severe enough, they say the loss of rainforest could cause the release of large volumes of carbon dioxide into the atmosphere, and could also disrupt plant and animal communities in one of the world’s most biodiversity-rich regions, as outlined in the Proceedings of the National Academy of Sciences (PNAS).


The team used ground-based rainfall measurements from the past three decades. Findings showed that since 1979, the dry season in southern Amazonia lasted about a week longer in each decade.

Professor Fu and her colleagues say the water stored in the forest soil at the end of each wet season is all that the trees have to last them through the dry months. The longer that lasts – regardless of how wet the wet season was – the more stressed the trees become and the more susceptible they are to forest fires.

They say the most likely explanation for the lengthening dry season in recent decades is human-caused greenhouse warming, which inhibits rainfall in two ways: It makes it harder for warm, dry air near the surface to rise and freely mix with cool, moist air above; and it blocks incursions by cold weather fronts from outside the tropics which could trigger rainfall.

Sydney Huang's curator insight, November 21, 2013 3:58 PM

I.D. The amazon rainforest may be losing trees due to dry seasons.


S.D. It was shown that in 1979, the dry season lasted about a week londer in each deacade.

S.D. The most likely explanation for these dry seasons is global warming.


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New Blood Glucose Test Sensor Uses Tear Fluid

New Blood Glucose Test Sensor Uses Tear Fluid | Amazing Science |
For those who suffer from diabetes, the pain that comes with pricking one's finger often discourages consistent blood glucose monitoring.


Tear glucose has been suggested previously as a potential approach for the noninvasive estimation of blood glucose. While the topic remains unresolved, an overview of previous studies suggests the importance of a tear sampling approach and warrants new technology development. A concept device is presented that meets the needs of a tear glucose biosensor.


Three approaches to chronoamperometric glucose sensing were evaluated, including glucose oxidase mediated by potassium ferricyanide or oxygen with a hydrogen peroxide catalyst, Prussian blue, and potassium ferricyanide-mediated glucose dehydrogenase. For tear sampling, calcium alginate, poly(2-hydroxyethyl methacrylate), and polyurethane foam were screened as an absorbent tear sampling material. A quantitative model based on the proposed function of concept device was created.For glucose sensing, it was found that potassium ferricyanide with glucose dehydrogenase was ideal, featuring oxygen insensitivity, long-term stability, and a lower limit of detection of 2 μM glucose.Polyurethane foam possessed all of the required characteristics for tear sampling, including reproducible sampling from a hydrogel-simulated, eye surface (4.2 ± 0.5 μl; n = 8). It is estimated that 100 μM of glucose tear fluid would yield 135 nA (14.9% relative standard deviation).


While the device has numerous challenges ahead, such as obtaining reproducible results, proof-of-concept has been demonstrated and the project has received backing from Mayo Clinic and BioAccel, an Arizona biomedical commercialization non-profit.

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The truth about T. rex: Even the most well known dinosaur kept some secrets

The truth about T. rex: Even the most well known dinosaur kept some secrets | Amazing Science |

In late 1905, newspaper reporters gushed over the bones of a prehistoric monster that palaeontologists had unearthed in the badlands of Montana. When The New York Times described the new 'Tyrant saurian', the paper declared it “the most formidable fighting animal of which there is any record whatsoever”. In the century since, Tyrannosaurus rex has not loosened its grip on the imaginations of the public or palaeontologists.

Stretching more than 12 meters from snout to tail and sporting dozens of serrated teeth the size of rail spikes, the 66-million-year-old T. rex remains the ultimate example of a prehistoric predator — so much so that a media frenzy erupted this year over a paper debating whether T. rex predominantly hunted or scavenged its meals. This infuriated many palaeontologists, who say the matter was resolved long ago by ample evidence showing that T. rex could take down prey and dismantle carrion. What particularly vexed researchers was that this non-issue overshadowed other, more important questions about T. rex.

The dinosaur's evolutionary origins, for example, are still a mystery. Researchers are eagerly trying to determine how these kings of the Cretaceous period (which spanned from 145 million to 66 million years ago) arose from a line of tiny dinosaurs during the Jurassic period (201 million to 145 million years ago). There is also considerable debate about what T. rex was like as a juvenile, and whether palaeontologists have spent decades mistaking its young for a separate species. Even the basic appearance of T. rex is in dispute: many researchers argue that the giant was covered in fluff or fuzz rather than scales. And then there is the vexing question of why T. rex had such a massive head and legs but relatively puny arms.

In the first few decades after palaeontologist Henry Fairfield Osborn named and described T. rex, researchers viewed this giant dinosaur as the culmination of a trend towards bigger predators. In this view, T. rex was seen as the descendent of Allosaurus, a 9-meter-long predator that lived more than 80 million years earlier. These and other massive carnivorous dinosaurs were lumped together in a categorical wastebasket called the Carnosauria, with T. rex as the last and biggest of the ferocious family. But palaeontologists tore up that evolutionary tree when they started using a more rigorous form of analysis called cladistics in the 1990s. They re-examined relationships between dinosaur groups and found that T. rex had its roots in a lineage of small, fuzzy creatures that lived in the shadow of Allosaurus and other predators during the Jurassic period.


The view that emerged placed T. rex and its close relatives — together known as tyrannosaurids — as the top twig on a broader evolutionary bush called the Tyrannosauroidea, which emerged around 165 million years ago. Among the earliest known members of this group was Stokesosaurus clevelandi, a bipedal carnivore 2–3 meters long that lived about 150 million years ago. Little is known about this creature, but evidence from other early tyrannosauroids suggests that Stokesosaurus had a long, low skull and slender arms. Early tyrannosauroids were small, agile predators, but their size placed them low in the pecking order during the Jurassic. “They were more lapdogs than top predators,” says Brusatte.

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Scientists develop implant that could stop Parkinson's growth

Scientists develop implant that could stop Parkinson's growth | Amazing Science |

A team in Bristol have created an implant that encourages cells damaged by the disease to grow again. It does this through a system of tubes and catheters that pump proteins into patients’ brain once a month, potentially stopping the disease from progressing by encouraging the damaged cells to grow again.


The port located behind a patient’s ear releases a protein called glial cell line-derived neurotrophic factor (GDNF). Six patients at Frenchay Hospital, Bristol, have trialled the system, and doctors are now looking for another 36 to help them continue their research.

Dr Kieran Breen, director of research and innovation at Parkinson's UK, said: “For years, the potential of GDNF as a treatment for Parkinson's has remained one of the great unanswered research questions.

”This new study will take us one step closer to finally answering this question once and for all.

Via Jeff Morris
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NASA rover confirms Mars origin of some meteorites that landed on Earth

NASA rover confirms Mars origin of some meteorites that landed on Earth | Amazing Science |

Examination of the Martian atmosphere by NASA’s Curiosity Mars rover confirms that some meteorites that have dropped to Earth really are from the Red Planet.


A key new measurement of the inert gas argon in Mars’ atmosphere by Curiosity’s laboratory provides the most definitive evidence yet of the origin of Mars meteorites while at the same time providing a way to rule out Martian origin of other meteorites.


The new measurement is a high-precision count of two forms of argon — argon-36 and argon-38 — accomplished by the Sample Analysis at Mars (SAM) instrument inside the rover. These lighter and heavier forms, or isotopes, of argon exist naturally throughout the solar system. On Mars the ratio of light to heavy argon is skewed because much of that planet’s original atmosphere was lost to space. The lighter form of argon was taken away more readily because it rises to the top of the atmosphere more easily and requires less energy to escape. That left the Martian atmosphere relatively enriched in the heavier isotope, argon-38.


Years of past analyses by Earth-bound scientists of gas bubbles trapped inside Martian meteorites had already narrowed the Martian argon ratio to between 3.6 and 4.5 (that is 3.6 to 4.5 atoms of argon-36 to every one of argon-38). Measurements by NASA’s Viking landers in the 1970s put the Martian atmospheric ratio in the range of four to seven. The new SAM direct measurement on Mars now pins down the correct argon ratio at 4.2.


“We really nailed it,” said Sushil Atreya of the University of Michigan, Ann Arbor, lead author of an Oct. 16 paper reporting the finding in Geophysical Research Letters. “This direct reading from Mars settles the case with all Martian meteorites.”


One reason scientists have been so interested in the argon ratio in Martian meteorites is that it was — before Curiosity — the best measure of how much atmosphere Mars has lost since the planet’s wetter, warmer days billions of years ago. Figuring out the planet’s atmospheric loss would enable scientists to better understand how Mars transformed from a once water-rich planet, more like our own, into today’s drier, colder and less-hospitable world.

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Physicists aim to make transition to quantum world visible

Physicists aim to make transition to quantum world visible | Amazing Science |
Theoretical physicist Frank Wilhelm-Mauch and his research team at Saarland University have developed a mathematical model for a type of microscopic test lab that could provide new and deeper insight into the world of quantum particles.


The new test system will enable the simultaneous study of one hundred light quanta (photons) and their complex quantum mechanical relationships ("quantum entanglement") – a far greater number than was previously possible. The researchers hope to gain new insights that will be of relevance to the development of quantum computers. They are the first group worldwide to undertake such studies using a so-called "metamaterial", a specially constructed lattice of nanostructures that is able to refract light more strongly than existing natural materials.


The theoretical physicist and his research group have used mathematical methods to develop a micro laboratory that is not dissimilar to a length of conventional antenna cable but that provides a controlled system with which to examine the transition between these two worlds. "We expect that quantum properties will become weaker or even disappear entirely above a certain system size. In order to be able to study this transition and the associated quantum state, we have developed a novel concept consisting of a very large test system of 100 distinguishable photons that will form the basis of measurements and that will enable these measurements to be carried out without losing a single photon. The cable itself will be made of superconducting material and the experiments will be carried out at low temperatures," explains Professor Wilhelm-Mauch. Up until now attempts to make these sorts of measurements have suffered from significant photon losses. Using the conventional methods available today a measurement on a system of 100 photons ends up measuring only one single photon. As the light quanta can simultaneously occupy several states, any measurement, once made, can provide only a very limited view of what is an extremely complex process. A single measured value can only ever describe one of the many possible states. "That's why we're making our test system with 100 photons as large as is practically feasible today, as this will allows us to study these highly entangled processes. The data from such measurements should give us a much more precise view of the processes involved," says Wilhelm-Mauch.


To do this the researchers "trick" the laws of conventional wave optics. They combine quantum optics with so-called "left-handed media" to transmit the light quanta through a metamaterial. These lattices of nanoscale structures have been the subject of research in conventional optics for quite some time and they have a very special property: light impinging on such a left-handed material is refracted more strongly than is possible in a naturally occurring material, such as water. The angle of refraction can be altered by modifying the structure of the material. The Saarbrücken physicists have come up with a mathematical model of a lattice that is tailored to microwave photons and that for the first time is good enough for quantum optic studies. The metamaterial devised by Wilhelm-Mauch's team is a so-called "left-handed artificial transmission line" that comprises a number of minute capacitors and inductors connected in series. The resulting waveguide allows a large number of photons to be packed into a tiny spatial volume, enabling them to be transmitted within a cable. The research team wants to use this system for quantum optic measurements.


The researchers are particularly interested in the transition from the world of classical physics to the quantum world. Knowing more about this interface will improve our understanding of macroscopic systems that make use of quantum effects. For instance, research of this kind could open up new possibilities in quantum computing. "If we can find out what is the maximum size of a system that still follows quantum mechanical laws, we would be able to make storage capacity as large as this limit allows," explains Frank Wilhelm-Mauch. The theoretical physicist is a member of the international quantum computing research network "SCALEQIT". As part of his work within the SCALEQIT project, Wilhelm-Mauch has already developed a highly efficient microwave detector that can detect photons with 100% efficiency. Currently scientists at the University of Karlsruhe in Germany and Syracuse University in the USA are working on a prototype of the micro lab.

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Making hydrogen easily is dream goal for sustainable energy: Bacteria have done that for billions of years

Making hydrogen easily is dream goal for sustainable energy: Bacteria have done that for billions of years | Amazing Science |

Making hydrogen easily and cheaply is a dream goal for clean, sustainable energy. Bacteria have been doing exactly that for billions of years, and now chemists at the University of California, Davis, and Stanford University are revealing how they do it, and perhaps opening ways to imitate them.


A study published Oct. 25, 2013 in the journal Science describes a key step in assembling the hydrogen-generating catalyst. "It's pretty interesting that bacteria can do this," said David Britt, professor of chemistry at UC Davis and co-author on the paper. "We want to know how nature builds these catalysts — from a chemist's perspective, these are really strange things."


The bacterial catalysts are based on precisely organized clusters of iron and sulfur atoms, with side groups of cyanide and carbon monoxide. Those molecules are highly toxic unless properly controlled, Britt noted.

The cyanide and carbon monoxide groups were known to come from the amino acid tyrosine, Britt said. Jon Kuchenreuther, a postdoctoral researcher in Britt's laboratory, used a technique called electron paramagnetic resonance to study the structure of the intermediate steps.


They found a series of chemical reactions involving a type of highly reactive enzyme called a radical SAM enzyme. The tyrosine is attached to a cluster of four iron atoms and four sulfur atoms, then cut loose leaving the cyanide and carbon monoxide groups behind.


"People think of radicals as dangerous, but this enzyme directs the radical chemistry, along with the production of normally poisonous CO and CN, along safe and productive pathways," Britt said. Kuchenreuther, Britt and colleagues also used another technique, Fourier Transform Infrared to study how the iron-cyanide-carbon monoxide complex is formed. That work will be published separately.


"Together, these results show how to make this interesting two-cluster enzyme," Britt said. "This is unique, new chemistry." Britt's laboratory houses the California Electron Paramagnetic Resonance center (CalEPR), the largest center of its kind on the west coast.

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Major ALS Breakthrough: Common Cause for ALS (Lou Gehrig’s disease) discovered

Major ALS Breakthrough: Common Cause for ALS (Lou Gehrig’s disease) discovered | Amazing Science |
Researchers discover common cause of all forms of ALS.


The underlying disease process of amyotrophic lateral sclerosis (ALS and Lou Gehrig’s disease), a fatal neurodegenerative disease that paralyzes its victims, has long eluded scientists and prevented development of effective therapies. Scientists weren’t even sure all its forms actually converged into a common disease process.


But a new Northwestern Medicine study for the first time has identified a common cause of all forms of ALS. The basis of the disorder is a broken down protein recycling system in the neurons of the spinal cord and the brain. Optimal functioning of the neurons relies on efficient recycling of the protein building blocks in the cells. In ALS, that recycling system is broken. The cell can’t repair or maintain itself and becomes severely damaged.


The discovery by Northwestern University Feinberg School of Medicine researchers, published in the journal Nature, provides a common target for drug therapy and shows that all types of ALS are, indeed, tributaries, pouring into a common river of cellular incompetence.


“This opens up a whole new field for finding an effective treatment for ALS,” said senior author Teepu Siddique, M.D., the Les Turner ALS Foundation/Herbert C. Wenske Professor of the Davee Department of Neurology and Clinical Neurosciences at Northwestern’s Feinberg School and a neurologist at Northwestern Memorial Hospital. ”We can now test for drugs that would regulate this protein pathway or optimize it, so it functions as it should in a normal state.”


The discovery of the breakdown in protein recycling may also have a wider role in other neurodegenerative diseases, specifically the dementias. These include Alzheimer’s disease and frontotemporal dementia as well as Parkinson’s disease, all of which are characterized by aggregations of proteins, Siddique said. The removal of damaged or misfolded proteins is critical for optimal cell functioning, he noted.


This breakdown occurs in all three forms of ALS: hereditary, which is called familial; ALS that is not hereditary, called sporadic; and ALS that targets the brain, ALS/dementia.


In related research, Feinberg School researchers also discovered a new gene mutation present in familial ALS and ALS/dementia, linking these two forms of the disease.


Siddique has been searching for the causes and underlying mechanism of ALS for more than a quarter century. He said he was initially drawn to it because, “It was one of the most difficult problems in neurology and the most devastating, a disease without any treatment or known cause.”


Siddique’s efforts first showed in 1989 that molecular genetics techniques were applicable to ALS, then described the first ALS gene locus in 1991, which led to the discovery of SOD1 and engineering of the first genetic animal model for ALS.


ALS affects an estimated 350,000 people worldwide, including children and adults, with about 50 percent of people dying within three years of its onset. In the motor disease, people progressively lose muscle strength until they become paralyzed and can no longer move, speak, swallow and breathe. ALS/dementia targets the frontal and temporal lobes of the brain, affecting patients’ judgment, the ability to understand language and to perform basic tasks like planning what to wear or organizing their day.

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Molecular crowding probably important factor for development of life on Earth

Molecular crowding probably important factor for development of life on Earth | Amazing Science |
How life came about from inanimate sets of chemicals is still a mystery.


Pasquale Stano at the University of Roma Tre and his colleagues were interested in using this knowledge to probe the origins of life. To make things simple, they chose an assembly that produces proteins. This assembly consists of 83 different molecules including DNA, which was programmed to produce a special green fluorescent protein (GFP) that could be observed under a confocal microscope.


The assembly can only produce proteins when its molecules are close enough together to react with each other. When the assembly is diluted with water, they can no longer react. This is one reason that the insides of living cells are very crowded, concentrated places: to allow the chemistry of life to work.


In order to recreate this molecular crowding, Stano added a chemical called POPC to the dilute solution. Fatty molecules such as POPC do not mix with water, and when placed into water they automatically form liposomes. These have a very similar structure to the membranes of living cells and are widely used to study the evolution of cells.


Stano reports in the journal Angewandte Chemie that many of these liposomes trapped some molecules of the assembly. But remarkably, five in every 1,000 such liposomes had all 83 of the molecules needed to produce a protein. These liposomes produced large amount of GFP and glowed green under a microscope.


Computer calculations reveal that even by chance, five liposomes in 1,000 could not have trapped all 83 molecules of the assembly. Their calculated probability for even one such liposome to form is essentially zero. The fact that any such liposomes formed and that GFP was produced means something quite unique is happening.


Stano and his colleagues do not yet understand why this happened. It may yet be a random process that a better statistical model will explain. It may be that these particular molecules are suited to this kind of self-organisation because they are already highly evolved. An important next step is to see if similar, but less complex, molecules are also capable of this feat.


Regardless of the limitations, Stano's experiment has shown for the first time that self-assembly into simple cells may be an inevitable physical process. Finding out how exactly this self-assembly happens will mean taking a big step towards understanding how life was formed.

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Grasshopper mice immune to pain and scorpion venom

Grasshopper mice immune to pain and scorpion venom | Amazing Science |
Mechanism for pain resistance in grasshopper mice suggests potential drug target.


When the grasshopper mouse attacks a bark scorpion, it barely notices the arachnid's intensely painful sting. Now researchers know why: the rodents have a mutation in the cellular pathway that controls their pain response, making them resistant to scorpion venom.

The finding, published recently in Science, suggests a potential target for researchers trying to develop pain-relieving drugs. “It’s a nice, complete study — from behavior right down to the molecule that explains the behaviour,” says Ewan Smith, a neuroscientist at the University of Cambridge, UK, who was not involved with the research.

The resistance to the venom helps grasshopper mice, which belong to the genus Onychomys and are only distantly related to ordinary house mice (Mus musculus), survive in the deserts of the southwestern United States. There, bark scorpions are plentiful, but other food resources are less common. Ashlee Rowe, an evolutionary neurobiologist at Michigan State University in East Lansing, and her colleagues confirmed field observations of the grasshopper mouse’s ability to withstand scorpion stings by injecting the paws of grasshopper mice and house mice with a small amount of venom. The house mice repeatedly licked their paws, indicating discomfort, but the grasshopper mice licked only a few times.

In a second experiment, the researchers injected house mice and grasshopper mice with venom and then with formalin, a chemical known to cause pain. The grasshopper mice still licked their paws less than the house mice, suggesting that the venom blocked the ability of the grasshopper mice to feel pain from the formalin.


The researchers next identified the molecular pathway that is modified in the neurons of grasshopper mice. Two sodium channels are necessary to transmit a pain signal in mammals: one that initiates the signal and one that propagates it. Drug research has focused mainly on the former; in humans, a rare mutation in that channel causes the inability to feel pain. Scorpion venom stimulates the initiating channel, but in grasshopper mice, it also inhibits the channel that controls propagation of the pain signal — thus preventing the pain it is supposed to cause.


Researchers think that a small structural difference between the pain-propagating sodium channels of the grasshopper mouse and of the house mouse can explain the species’ reactions to scorpion venom. In grasshopper mice, the protein making up the sodium channel differs by one amino acid near the channel's opening. Without that change, venom cannot inhibit the channel propogating pain signals.

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The Futurist magazine’s top 10 forecasts for 2014 and beyond — and Why They Might Not Come True

The Futurist magazine’s top 10 forecasts for 2014 and beyond — and Why They Might Not Come True | Amazing Science |

The Futurist magazine’s top 10 forecasts for 2014 and beyond. 

Every year, the editors of the Futurist magazine identify the most provocative forecasts and statements about the future that we’ve published recently and we put them to into an annual report called “Outlook.” It’s sprawling exploration of what the future looks like at a particular moment in time. To accompany the report, we draft a list of our top 10 favorite predictions from the magazine’s previous 12 months. What are the criteria to be admitted into the top 10? The forecast should be interesting, relatively high impact, and rising in likelihood. In other words, it’s a bit subjective.


There are surely better methods for evaluating statements about the future, but not for our purposes. You see, we aren’t actually interested in attempting to tell our readers what will happen so much as provoking a better discussion about what can happen—and what futures can be avoided, if we discover we’re heading in an unsavory direction.


The future isn’t a destination. But the problem with too many conversations about the future, especially those involving futurists, is that predictions tend to take on unmitigated certainty, sounding like GPS directions. When you reach the Singularity, turn left—that sort of thing. In reality, it’s more like wandering around a city, deciding spur of the moment what road to take.

Via Szabolcs Kósa, Margarida Sá Costa
Say Keng Lee's curator insight, October 7, 2013 5:06 AM

Fascinating forecasts!

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Using sound waves for bomb detection

Using sound waves for bomb detection | Amazing Science |

A remote acoustic detection system designed to identify homemade bombs can determine the difference between those that contain low-yield and high-yield explosives.


That capability – never before reported in a remote bomb detection system – was described in a paper by Vanderbilt engineer Douglas Adams presented at the American Society of Mechanical Engineers Dynamic Systems and Control Conference on Oct. 23 in Stanford, CA.

A number of different tools are currently used for explosives detection.


These range from dogs and honeybees to mass spectrometry, gas chromatography and specially designed X-ray machines.


"Existing methods require you to get quite close to the suspicious object," said Adams, Distinguished Professor of Civil and Environmental Engineering. "The idea behind our project is to develop a system that will work from a distance to provide an additional degree of safety."

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Surprising: Quantum Experiment Shows How Time ‘Emerges’ from Entanglement

Surprising: Quantum Experiment Shows How Time ‘Emerges’ from Entanglement | Amazing Science |

Then in 1983, the theorists Don Page and William Wooters came up with a novel solution based on the quantum phenomenon of entanglement. This is the exotic property in which two quantum particles share the same existence, even though they are physically separated.


Entanglement is a deep and powerful link and Page and Wooters showed how it can be used to measure time. Their idea was that the way a pair of entangled particles evolve is a kind of clock that can be used to measure change.


But the results depend on how the observation is made. One way to do this is to compare the change in the entangled particles with an external clock that is entirely independent of the universe. This is equivalent to god-like observer outside the universe measuring the evolution of the particles using an external clock.


In this case, Page and Wooters showed that the particles would appear entirely unchanging—that time would not exist in this scenario.


But there is another way to do it that gives a different result. This is for an observer inside the universe to compare the evolution of the particles with the rest of the universe. In this case, the internal observer would see a change and this difference in the evolution of entangled particles compared with everything else is an important a measure of time.


This is an elegant and powerful idea. It suggests that time is an emergent phenomenon that comes about because of the nature of entanglement. And it exists only for observers inside the universe. Any god-like observer outside sees a static, unchanging universe, just as the Wheeler-DeWitt equations predict.


Of course, without experimental verification, Page and Wooter’s ideas are little more than a philosophical curiosity. And since it is never possible to have an observer outside the universe, there seemed little chance of ever testing the idea.


Until now. Today, Ekaterina Moreva at the Istituto Nazionale di Ricerca Metrologica (INRIM) in Turin, Italy, and a few pals have performed the first experimental test of Page Wooters ideas. And they confirm that time is indeed an emergent phenomenon for ‘internal’ observers but absent for external ones.


In the last years several theoretical papers discussed if time can be an emergent property deriving from quantum correlations. Here, to provide an insight into how this phenomenon can occur, physicists present an experiment that illustrates Page and Wootters' mechanism of "static" time, and Gambini subsequent refinements. A static, entangled state between a clock system and the rest of the universe is perceived as evolving by internal observers that test the correlations between the two subsystems. They implement this mechanism using an entangled state of the polarization of two photons, one of which is used as a clock to gauge the evolution of the second: an "internal" observer that becomes correlated with the clock photon sees the other system evolve, while an "external" observer that only observes global properties of the two photons can prove it is static.

Sharrock's curator insight, October 28, 2013 10:07 AM

from the article: "This is an elegant and powerful idea. It suggests that time is an emergent phenomenon that comes about because of the nature of entanglement. And it exists only for observers inside the universe. Any god-like observer outside sees a static, unchanging universe, just as the Wheeler-DeWitt equations predict."

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The World's Most Powerful MRI Takes Shape

The World's Most Powerful MRI Takes Shape | Amazing Science |

An MRI scanner equipped with a superconducting magnet strong enough to lift a 60-metric-ton battle tank will offer unprecedented images of the human brain when it comes on line a little more than a year from now, say its builders.


The imager’s superconducting electromagnet is designed to produce a field of 11.75 teslas, making it the world’s most powerful whole-body scanner.


Most standard hospital MRIs produce 1.5 or 3 T. A few institutions, including the University of Illinois at Chicago and Maastricht University, in the Netherlands, have recently installed human scanners that can reach 9.4 T. Superconducting magnets used in the Large Hadron Collider, which last year was used in the discovery of the Higgs boson, produce a field of 8.4 T.


The development of the scanner, known as INUMAC (for Imaging of Neuro disease Using high-field MR And Contrastophores), has been in progress since 2006 and is expected to cost €200 million, or about US $270 million. The project reached a key milestone this summer with delivery of more than 200 kilometers of superconducting cable, which is now being wound into coils that will produce the scanner’s magnetic field.


“We’re pretty proud of having met all the requirements, plus given them a little extra,” says Hem Kanithi, vice president of business development at Luvata, in Waterbury, Conn., which built the superconductor.

Standard hospital scanners have a spatial resolution of about 1 millimeter, covering about 10 000 neurons, and a time resolution of about a second. The INUMAC will be able to image an area of about 0.1 mm, or 1000 neurons, and see changes occurring as fast as one-tenth of a second, according to Pierre Védrine, director of the project at the French Alternative Energies and Atomic Energy Commission, in Paris.


With this type of resolution, MRIs could detect early indications of brain diseases such as Alzheimer’s or Parkinson’s and perhaps measure the effects of any methods developed to treat those illnesses. It would also allow much more precise functional imaging of the brain at work than is currently available. “You cannot really discriminate today what is happening inside your brain at the level of a few hundred neurons,” Védrine says.

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Brain decoding: Reading minds

Brain decoding: Reading minds | Amazing Science |

By scanning blobs of brain activity, scientists may be able to decode people's thoughts, their dreams and even their intentions. Media reports have suggested that such techniques bring mind-reading “from the realms of fantasy to fact”, and “could influence the way we do just about everything”. The Economist in London even cautioned its readers to “be afraid”, and speculated on how long it will be until scientists promise telepathy through brain scan.


Although companies are starting to pursue brain decoding for a few applications, such as market research and lie detection, scientists are far more interested in using this process to learn about the brain itself. Gallant's group and others are trying to find out what underlies those different brain patterns and want to work out the codes and algorithms the brain uses to make sense of the world around it. They hope that these techniques can tell them about the basic principles governing brain organization and how it encodes memories, behaviour and emotion.


Brain decoding took off about a decade ago, when neuroscientists realized that there was a lot of untapped information in the brain scans they were producing using functional magnetic resonance imaging (fMRI). That technique measures brain activity by identifying areas that are being fed oxygenated blood, which light up as coloured blobs in the scans. To analyse activity patterns, the brain is segmented into little boxes called voxels — the three-dimensional equivalent of pixels — and researchers typically look to see which voxels respond most strongly to a stimulus, such as seeing a face. By discarding data from the voxels that respond weakly, they conclude which areas are processing faces.


Decoding techniques interrogate more of the information in the brain scan. Rather than asking which brain regions respond most strongly to faces, they use both strong and weak responses to identify more subtle patterns of activity. Early studies of this sort proved, for example, that objects are encoded not just by one small very active area, but by a much more distributed array.


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Vegetarian piranha and cat-purring monkey among newly discovered species in the Amazon basin

Vegetarian piranha and cat-purring monkey among newly discovered species in the Amazon basin | Amazing Science |

A purring monkey, a vegetarian piranha and a flame-patterned lizard are among the most fascinating species to be discovered in the Amazon rainforest over the last four years. At least 441 species of plant and animal were found in the Amazon basin between 2010 and 2013. The flora and fauna has been catalogued by the World Wide Fund (WWF).

The list includes 258 plants, 84 fish, 58 amphibians, 22 reptiles, 18 birds and one mammal.


Countless insects and other invertebrates discovered that were not listed. The report was produced as part of an initiative run by WWF and Sky to help save the rainforests. I Love Amazon Week runs between 21 and 27 October 2013. 


Damian Fleming, head of programmes for Brazil and the Amazon at WWF-UK, said: "The more scientists look, the more they find. With an average of two new species identified every week for the past four years, it's clear that the extraordinary Amazon remains one of the most important centres of global biodiversity."


The mammal discovered was a purring monkey. The Caqueta titi monkey is one of about 20 species of titi monkey, all of which live in the Amazon basin. It is already considered critically endangered.


Thomas Defler, one of the scientists who discovered the species, said the young Caqueta titi monkeys have a particularly endearing trait: "When they feel very content they purr towards each other."


The Gonatodes timidus lizard has flamed "warpaint" colouring and was found in the part of the Amazon that extends into Guyana. Despite their aggressive pigmentation, the species is very shy and avoids humans.


A frog the size of a thimble, an Allobates amissibilis, was found in an area set to be opened to tourists, raising concerns that the already endangered species could face further threat and "may be lost" due to human activity.


The vegetarian piranha found living in rocky rapids was named the Tometes camunani and is in danger of losing its main food source because of mining activity threatening the flow of its river home. "The richness of the Amazon's forests and freshwater habitats continues to amaze the world," Fleming said.


"But these same habitats are also under growing threat. The discovery of these new species reaffirms the importance of stepping-up commitments to conserve and sustainably manage the unique biodiversity and also the goods and services provided by the rainforests to the people and businesses of the region."

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Physicists decode three-way genetic decision switch of cancer metastasis

Physicists decode three-way genetic decision switch of cancer metastasis | Amazing Science |
Researchers from Rice University's Center for Theoretical Biological Physics have deciphered the operating principles of a genetic circuit that allows cancer to metastasize.


“Cancer cells behave in complex ways, and this work shows how such complexity can arise from the operation of a relatively simple decision-making circuit,” said study co-author Eshel Ben-Jacob, a senior investigator at Rice’sCenter for Theoretical Biological Physics (CTBP) and adjunct professor of biochemistry and cell biology at Rice. “By stripping away the complexity and starting with first principles, we get a glimpse of the ‘logic of cancer’ — the driver of the disease’s decision to spread.”


In the PNAS study, Ben-Jacob and CTBP colleagues José Onuchic, Herbert Levine, Mingyang Lu and Mohit Kumar Jolly describe a new theoretical framework that allowed them to model the behavior of microRNAs in decision-making circuits. To test the framework, they modeled the behavior of a decision-making genetic circuit that cells use to regulate the forward and backward transitions between two different cell states, the epithelial and mesenchymal. Known respectively as the E-M transition (EMT) and the M-E transition (MET), these changes in cell state are vital for embryonic development, tissue engineering and wound healing. During the EMT, some cells also form a third state, a hybrid that is endowed with a special mix of both epithelial and mesenchymal abilities, including group migration.


The EMT transition is also a hallmark of cancer metastasis. Cancer cells co-opt the process to allow tumor cells to break away, migrate to other parts of the body and establish a new tumor. To find ways to shut down metastasis, cancer researchers have conducted dozens of studies about the genetic circuitry that activates the EMT.


One clear finding from previous studies is that a two-component genetic switch is the key to both the EMT and MET. The switch contains two specialized pairs of proteins. One pair is SNAIL and microRNA34 (SNAIL/miR34), and the other is ZEB and microRNA200 (ZEB/miR200). Each pair is “mutually inhibitory,” meaning that the presence of one of the partners inhibits the production of the other.

In the mesenchymal cell state — the state that corresponds to cancer metastasis — both SNAIL and ZEB must be present in high levels. In the epithelial state, the microRNA partners dominate, and neither ZEB nor SNAIL is available in high levels.


“Usually, if you have two genes that are mutually limiting, you have only two possibilities,” Ben-Jacob said. “In the first case, gene A is highly expressed and inhibits gene B. In the other, gene B is highly expressed and it inhibits A. This is true in the case of ZEB and miR200. One of these is ‘on’ and the other is ‘off,’ so it’s clear that this is the decision element in the switch.”


SNAIL and miR34 interact more weakly. As a result, both can be present at the same time, with the amount of each varying based upon inputs from a number of other proteins, including several other cancer genes.



“One of the most important things the model showed us was how SNAIL and miR34 act as an integrator,” Ben-Jacob said. “This part of the circuit is acted on by multiple cues, and it integrates those signals and feeds information into the decision element. It does this based upon the level of SNAIL, which activates ZEB and inhibits miR200.”

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New device to store electricity on silicon chips themselves

New device to store electricity on silicon chips themselves | Amazing Science |

All the things that define us in a modern environment require electricity,” said Pint. “The more that we can integrate power storage into existing materials and devices, the more compact and efficient they will become.” New device stores electricity on silicon chips.


Solar cells that produce electricity 24/7, not just when the sun is shining. Mobile phones with built-in power cells that recharge in seconds and work for weeks between charges. These are just two of the possibilities raised by a novel supercapacitor design invented by material scientists at Vanderbilt University that is described in a paper published in the Oct. 22, 2013 issue of the journal Scientific Reports.

It is the first supercapacitor that is made out of silicon so it can be built into a silicon chip along with the microelectronic circuitry that it powers. In fact, it should be possible to construct these power cells out of the excess silicon that exists in the current generation of solar cells, sensors, mobile phones and a variety of other electromechanical devices, providing a considerable cost savings.


“If you ask experts about making a supercapacitor out of silicon, they will tell you it is a crazy idea,” said Cary Pint, the assistant professor of mechanical engineering who headed the development. “But we’ve found an easy way to do it.”

Instead of storing energy in chemical reactions the way batteries do, “supercaps” store electricity by assembling ions on the surface of a porous material. As a result, they tend to charge and discharge in minutes, instead of hours, and operate for a few million cycles, instead of a few thousand cycles like batteries.

“The big challenge for this approach is assembling the materials,” said Pint. “Constructing high-performance, functional devices out of nanoscale building blocks with any level of control has proven to be quite challenging, and when it is achieved it is difficult to repeat.” 

With experience in growing carbon nanostructures, Pint’s group decided to try to coat the porous silicon surface with carbon. “We had no idea what would happen,” said Pint. “Typically, researchers grow graphene from silicon-carbide materials at temperatures in excess of 1400 degrees Celsius. But at lower temperatures – 600 to 700 degrees Celsius – we certainly didn’t expect graphene-like material growth.”



When the researchers pulled the porous silicon out of the furnace, they found that it had turned from orange to purple or black. When they inspected it under a powerful scanning electron microscope they found that it looked nearly identical to the original material but it was coated by a layer of graphene a few nanometers thick.



When the researchers tested the coated material they found that it had chemically stabilized the silicon surface. When they used it to make supercapacitors, they found that the graphene coating improved energy densities by over two orders of magnitude compared to those made from uncoated porous silicon and significantly better than commercial supercapacitors.


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Kinase Suppressor or ras (KSR2) Mutations Are Associated with Obesity and Insulin Resistance

Kinase Suppressor or ras (KSR2) Mutations Are Associated with Obesity and Insulin Resistance | Amazing Science |

Cells sense the nutritional status of the organism, monitor intracellular energy stores, and transmit this information to signal transduction pathways that drive cellular proliferation and differentiation. The Ras-Raf-MEK signaling pathway is fundamental to cellular metabolism and growth in humans and inherited mutations involving this pathway cause disorders of early growth and development, whereas sporadic activating mutations have been identified in at least 30% of human cancers. Circulating hormones and growth factors activate cell surface receptor tyrosine kinases, stimulating the GTP loading of Ras, which permits recruitment of the cytosolic Ser/Thr protein kinase Raf to the plasma membrane, where it is activated. Membrane-bound Raf phosphorylates and activates the dual-specificity kinase MEK, which in turn phosphorylates ERK, which then translocates to the nucleus where it regulates gene expression.

Kinase suppressor of Ras 2 (KSR2) is an intracellular scaffolding protein involved in multiple signaling pathways. Targeted deletion of Ksr2leads to obesity in mice, suggesting a role in energy homeostasis. We explored the role of KSR2 in humans by sequencing 2,101 individuals with severe early-onset obesity and 1,536 controls. We identified multiple rare variants in KSR2 that disrupt signaling through the Raf-MEK-ERK pathway and impair cellular fatty acid oxidation and glucoseoxidation in transfected cells; effects that can be ameliorated by the commonly prescribed antidiabetic drug, metformin. Mutation carriers exhibit hyperphagia in childhood, low heart rate, reduced basal metabolic rate and severe insulin resistance. These data establish KSR2 as an important regulator of energy intake, energy expenditure, and substrate utilization in humans. Modulation of KSR2-mediated effects may represent a novel therapeutic strategy for obesity and type 2 diabetes.

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Sensory Substitution and Brain Plasticity: How to Augment our Senses

Since 1968 scientists have been creating sensory substitution and augmentation devices. With these devices they try to replace or enhance one sense by using another sense. For example, in tactile–vision, stimulation of the skin driven by input to a camera is used to replace the ordinary sense of vision that uses our eyes. The feelSpace belt aims to give people a magnetic sense of direction using vibrotactile stimulation driven by a digital compass. This talk discusses these developing technologies, mentions psychologists studying the minds and behavior of subjects who use these kind of devices, and analyzes the nature of perceptual experience and sensory interaction. The talk also explores the nature, limits and possibilities of these technologies, how they can be used to help those with sensory impairments, and what they can tell us about perception and perceptual experience in general.

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Thousands of small regions of DNA influence the way facial features develop

Thousands of small regions of DNA influence the way facial features develop | Amazing Science |

Scientists are starting to understand why one person's face can look so different from another's. Working on mice, researchers have identified thousands of small regions of DNA that influence the way facial features develop.

The study also shows that tweaks to genetic material can subtly alter face shape. The findings, published in Science, could also help researchers to learn how facial birth defects arise.

The researchers said that although the work was carried out on animals, the human face was likely to develop in the same way.

Professor Axel Visel, from the Joint Genome Institute at the Lawrence Berkeley National Laboratory in California, told BBC News: "We're trying to find out how these instructions for building the human face are embedded in human DNA.


"Somewhere in there there must be that blueprint that defines what our face looks like." The international team has found more than 4,000 "enhancers" in the mouse genome that appear to play a role in facial appearance.

These short stretches of DNA act like switches, turning genes on and off. And for 200 of these, the researchers have identified how and where they work in developing mice. Prof. Visel said: "In the mouse embryos we can see where exactly, as the face develops, this switch turns on the gene that it controls.

The scientists also looked at what happened when three of these genetic switches were removed from mice. "These mice looked pretty normal, but it is really hard for humans to see differences in the face of mice," explained Prof. Visel. "The way we can get around this is to use CT scans to study the shapes of the skulls of these mice. We take them and scan their heads. then we can measure the shape of the skull of these mice and we can do this in a very precise way."

By comparing the transgenic mice with unmodified mice, the researchers found that the changes were very subtle. However some mice developed longer or shorter skulls, while others have wider or narrower faces. "What this really tells us is that this particular switch also plays a role in development of the skull and can affect what exactly the skull looks like," he explained.

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Vanishing hope for a cure: Reservoir of inactive HIV viruses may be 60 times larger than thought

Vanishing hope for a cure: Reservoir of inactive HIV viruses may be 60 times larger than thought | Amazing Science |

Hopes of a total cure for HIV have been dealt a blow, after researchers in the US discovered that the "reservoir" of inactive viruses in a patient's body may be up to 60 times larger than previously thought.

Although modern drug treatments have proved hugely effective at controlling the HIV virus, enabling patients to live long and full lives and reducing infection rates, they do not kill all the viruses in an infected individual.


These viruses remain a threat because they can become active again if a patient stops taking their antiretroviral drugs. The findings, published in the journal Cell following a study at the Howard Hughes Medical Institute (HHMI) in Maryland, were "discouraging" experts said, but should re-focus efforts to make sure HIV positive people are getting the treatment they need.

"The findings suggest that there are a lot more of these proviruses that we have to worry about than we thought," said Robert Siliciano, an HHMI investigator at The Johns Hopkins University, who led the new study. "It doesn't mean that it's hopeless, but it does mean we need to focus on getting an even clearer idea of the scope of the problem."


In HIV positive patients the virus targets the immune system's T cells, and becomes integrated into the cell's genes, making the cell reproduce the virus. Antiretroviral drugs target these active forms of the virus, but in some cells, the virus remains inactive. It is this type of virus that researchers now believe is far more numerous than previously thought. As of yet, researchers have no way of eradicating inactive HIV viruses.

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Bees Underwent Massive Extinction When Dinosaurs Did

Bees Underwent Massive Extinction When Dinosaurs Did | Amazing Science |

For the first time ever, scientists have documented a widespread extinction of bees that occurred 65 million years ago, concurrent with the massive event that wiped out land dinosaurs and many flowering plants.

Previous studies have suggested a widespread extinction among flowering plants at the K-T boundary, and it’s long been assumed that the bees who depended upon those plants would have met the same fate. Yet unlike the dinosaurs, “there is a relatively poor fossil record of bees,” says Rehan, making the confirmation of such an extinction difficult.


Rehan and colleagues overcame the lack of fossil evidence for bees with a technique called molecular phylogenetics. Analyzing DNA sequences of four “tribes” of 230 species of carpenter bees from every continent except Antarctica for insight into evolutionary relationships, the researchers began to see patterns consistent with a mass extinction. Combining fossil records with the DNA analysis, the researchers could introduce time into the equation, learning not only how the bees are related but also how old they are.


“The data told us something major was happening in four different groups of bees at the same time,” says Rehan, of UNH’s College of Life Sciences and Agriculture. “And it happened to be the same time as the dinosaurs went extinct.”


While much of Rehan’s work involves behavioral observation of bees native to the northeast of North America, this research taps the computer-heavy bioinformatics side of her research, assembling genomic data to elucidate similarities and differences among the various species over time. Marrying observations from the field with genomic data, she says, paints a fuller picture of these bees’ behaviors over time.


“If you could tell their whole story, maybe people would care more about protecting them,” she says. Indeed, the findings of this study have important implications for today’s concern about the loss in diversity of bees, a pivotal species for agriculture and biodiversity.


“Understanding extinctions and the effects of declines in the past can help us understand the pollinator decline and the global crisis in pollinators today,” Rehan says.

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The music video for 65daysofstatic’s new track “PRISMS” was entirely made by a computer algorithm

The music video for 65daysofstatic’s new track “PRISMS” was entirely made by a computer algorithm | Amazing Science |

Matt Pearson decided to prove wrong Alex Rutterford, the director of Autechre’s “Gantz Graf“, who said back in 2002 that a computer program could not make a music video on its own. Well, more than 10 years later, this feat has become possible. Pearson only wrote the algorithm and the system made all the artistic decisions such as the camera work by itself, based on its interpretation of the audio track.

Matt Pearson insists that he does not want to be labeled as a designer but rather as a coder. If he is indeed part of the design process, his work only creates the environment in which the generative animation evolves on its own. What was unthinkable ten years ago has now become a reality, so what will it be ten years from now? Algorithms creating other algorithms? Probably so. I don’t know if this perspective is exciting or terrifying.

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Farthest confirmed galaxy is a prolific star creator

Farthest confirmed galaxy is a prolific star creator | Amazing Science |

Astronomers have measured the distance of the farthest known galaxy, finding that its light took 13.1 billion years to reach Earth – which means the light was emitted just 700 million years after the Big Bang. Although the galaxy is much smaller than the Milky Way, it is forming stars at a much faster rate. The discovery provides important new information about the epoch of reionization, the ancient era when the neutral gas between galaxies became ionized.


To observe the farthest galaxies, astronomers exploit the universe's expansion, which stretches – or redshifts – the light waves of distant objects to longer, or redder, wavelengths. But dust can also redden light, so a red colour alone does not guarantee that a galaxy lies at the edge of the observable universe.


"The problem had been, over the previous few years, [that] people have been trying to confirm these really distant galaxies – and for the most part coming up empty," says Steven Finkelstein, an astronomer at the University of Texas at Austin.


Confirmation of a far-off galaxy's distance requires measuring the redshift of lines in the spectrum of light that it emits. This means that astronomers face the challenge of obtaining the spectrum of a faint object. So for two nights in April, Finkelstein took aim at 43 red objects in the constellation Ursa Major with one of the largest telescopes in the world, the 10-metre Keck I telescope atop Mauna Kea in Hawaii. A year earlier, this telescope had received a more sensitive spectrograph, which made Finkelstein's observations possible.


Finkelstein searched the spectra for a line from Lyman-alpha emission. This radiation arises when an electron falls from the n = 2 to the n = 1 state of hydrogen, which is the most abundant element in the cosmos. This spectral line normally emits far-ultraviolet radiation at a wavelength of 1216 Å (121.6 nm), but because of the hoped-for redshifts, Finkelstein obtained his spectra at near-infrared wavelengths instead.


In 42 of the 43 spectra, Finkelstein saw no lines. "I was disappointed, I think – until I figured out the redshift of the one we did see and realized it was the most distant one." That galaxy, bearing the unwieldy name z8_GND_5296, has a Lyman-alpha line at a wavelength of 10,343 Å (1.0343 μm), a 751% increase over the rest wavelength, which means that the galaxy's redshift is 7.51. It is 40 million light-years more remote than the previous record holder, at redshift 7.215.

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