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Researchers create fastest spinning man-made object: Microsphere spins with 600 million revolutions / min

Researchers create fastest spinning man-made object: Microsphere spins with 600 million revolutions / min | Amazing Science | Scoop.it

A team of researchers claims to have created the world's fastest spinning man-made object. They were able to levitate and spin a microscopic sphere at speeds of up to 600 million revolutions per minute.

 

This spin speed is half a million times faster than a domestic washing machine and more than a thousand times faster than a dental drill. The work by the University of St Andrews scientists is published in Nature Communications.

 

Although there is much international research exploring what happens at the boundary between classical physics and quantum physics, most of this experimental work uses atoms or molecules. The St Andrews team aimed to understand what happened for larger objects containing a million million atoms or more.

 

To do this they manufactured a microscopic sphere of calcium carbonate only four millionths of a metre in diameter. The team then used the miniscule forces of laser light to hold the sphere with the radiation pressure of light - rather like levitating a beach ball with a jet of water.

 

They exploited the property of polarisation of the laser light that changed as the light passed through the levitating sphere, exerting a small twist or torque.

 

Placing the sphere in vacuum largely removed the drag due to any gas environment, allowing the team to achieve the very high rotation rates.

 

In addition to the rotation, the team observed a "compression" of the excursions or "wobble" of the particle in all three dimensions, which can be understood as a "cooling" of the motion.

 

Essentially the particle behaved like the world's smallest gyroscope, stabilising its motion around the axis of rotation. The rotation rate is so fast that the angular acceleration at the sphere surface is one billion times that of gravity on the Earth surface”


Dr Yoshihiko Arita of the university's School of Physics and Astronomy said: "This is an exciting, thought-provoking experiment that pushes the boundary of our understanding of rotating bodies.

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20,000+ FREE Online Science and Technology Lectures from Top Universities

20,000+ FREE Online Science and Technology Lectures from Top Universities | Amazing Science | Scoop.it

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Rapid dynamic reprogramming of matter

Rapid dynamic reprogramming of matter | Amazing Science | Scoop.it

Engineering switchable reconfigurations in DNA-controlled nanoparticle arrays could lead to dynamic energy-harvesting or responsive optical materials


The rapid development of self-assembly approaches has enabled the creation of materials with desired organization of nanoscale components. However, achieving dynamic control, wherein the system can be transformed on demand into multiple entirely different states, is typically absent in atomic and molecular systems and has remained elusive in designed nanoparticle systems. Here, we demonstrate with in situ small-angle X-ray scattering that, by using DNA strands as inputs, the structure of a three-dimensional lattice of DNA-coated nanoparticles can be switched from an initial ‘mother phase into one of multiple ‘daughter phases. The introduction of different types of reprogramming DNA strands modifies the DNA shells of the nanoparticles within the superlattice, thereby shifting interparticle interactions to drive the transformation into a particular daughter phase. Moreover, we mapped quantitatively with free-energy calculations the selective reprogramming of interactions onto the observed daughter phases.


Scientists at the U.S. Department of Energy’s Brookhaven National Laboratory have developed the capability of creating dynamic nanomaterials — ones whose structure and associated properties can be switched, on-demand. In a paper appearing in Nature Materials, they describe a way to selectively rearrange nanoparticles in three-dimensional arrays to produce different configurations, or “phases,” from the same nano-components.


“One of the goals in nanoparticle self-assembly has been to create structures by design,” said Oleg Gang, who led the work at Brookhaven’s Center for Functional Nanomaterials (CFN), a DOE Office of Science User Facility. “Until now, most of the structures we’ve built have been static.” KurzweilAI covered that development in a previous article, “Creating complex structures using DNA origami and nanoparticles.”


The new advance in nanoscale engineering builds on that previous work in developing ways to get nanoparticles to self-assemble into complex composite arrays, including linking them together with tethers constructed of complementary strands of synthetic DNA.


“We know that properties of materials built from nanoparticles are strongly dependent on their arrangements,” said Gang. “Previously, we’ve even been able to manipulate optical properties by shortening or lengthening the DNA tethers. But that approach does not permit us to achieve a global reorganization of the entire structure once it’s already built.”

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New Invention captures wasted cell phone energy and feeds it back to battery

New Invention captures wasted cell phone energy and feeds it back to battery | Amazing Science | Scoop.it

Engineers  at The Ohio State University have created a circuit that makes cell phone batteries last up to 30 percent longer on a single charge. The trick: it converts some of the radio signals emanating from a phone into direct current (DC) power, which then charges the phone’s battery.

This new technology can be built into a cell phone case, adding minimal bulk and weight.


“When we communicate with a cell tower or Wi-Fi router, so much energy goes to waste,” explained Chi-Chih Chen, research associate professor of electrical and computer engineering. “We recycle some of that wasted energy back into the battery.”


“Our technology is based on harvesting energy directly from the source, explained Robert Lee, professor of electrical and computer engineering. By Lee’s reckoning, nearly 97 percent of cell phone signals never reach a destination and are simply lost. Some of the that energy can be captured.

The idea is to siphon off just enough of the radio signal to noticeably slow battery drain, but not enough to degrade voice quality or data transmission.


Cell phones broadcast in all directions at once to reach the nearest cell tower or Wi-Fi router. Chen and his colleagues came up with a system that identifies which radio signals are being wasted. It works only when a phone is transmitting.


Next, the engineers want to insert the device into a “skin” that sticks directly to a phone, or better, partner with a manufacturer to build it directly into a phone, tablet or other portable electronic device.

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Memories that have been "lost" as a result of amnesia can be recalled by activating brain cells with light

Memories that have been "lost" as a result of amnesia can be recalled by activating brain cells with light | Amazing Science | Scoop.it

In a paper published today in the journal Science, researchers at MIT reveal that they were able to reactivate memories that could not otherwise be retrieved, using a technology known as optogenetics.

The finding answers a fiercely debated question in neuroscience as to the nature of amnesia, according to Susumu Tonegawa, the Picower Professor in MIT's Department of Biology and director of the RIKEN-MIT Center at the Picower Institute for Learning and Memory, who directed the research by lead authors Tomas Ryan, Dheeraj Roy, and Michelle Pignatelli.


Neuroscience researchers have for many years debated whether retrograde amnesia -- which follows traumatic injury, stress, or diseases such as Alzheimer's -- is caused by damage to specific brain cells, meaning a memory cannot be stored, or if access to that memory is somehow blocked, preventing its recall. "The majority of researchers have favored the storage theory, but we have shown in this paper that this majority theory is probably wrong," Tonegawa says. "Amnesia is a problem of retrieval impairment."


Memory researchers have previously speculated that somewhere in the brain network is a population of neurons that are activated during the process of acquiring a memory, causing enduring physical or chemical changes. If these groups of neurons are subsequently reactivated by a trigger such as a particular sight or smell, for example, the entire memory is recalled. These neurons are known as "memory engram cells."


In 2012 Tonegawa's group used optogenetics -- in which proteins are added to neurons to allow them to be activated with light -- to demonstrate for the first time that such a population of neurons does indeed exist in an area of the brain called the hippocampus. However, until now no one has been able to show that these groups of neurons do undergo enduring chemical changes, in a process known as memory consolidation. One such change, known as "long-term potentiation" (LTP), involves the strengthening of synapses, the structures that allow groups of neurons to send signals to each other, as a result of learning and experience.


To find out if these chemical changes do indeed take place, the researchers first identified a group of engram cells in the hippocampus that, when activated using optogenetic tools, were able to express a memory. When they then recorded the activity of this particular group of cells, they found that the synapses connecting them had been strengthened. "We were able to demonstrate for the first time that these specific cells -- a small group of cells in the hippocampus -- had undergone this augmentation of synaptic strength," Tonegawa says.


The researchers then attempted to discover what happens to memories without this consolidation process. By administering a compound called anisomycin, which blocks protein synthesis within neurons, immediately after mice had formed a new memory, the researchers were able to prevent the synapses from strengthening. When they returned one day later and attempted to reactivate the memory using an emotional trigger, they could find no trace of it. "So even though the engram cells are there, without protein synthesis those cell synapses are not strengthened, and the memory is lost," Tonegawa says.


But startlingly, when the researchers then reactivated the protein synthesis-blocked engram cells using optogenetic tools, they found that the mice exhibited all the signs of recalling the memory in full.

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Parasites Are Wiping Out Entire Honeybee Colonies – Magnitude Much Higher Than Previously Thought

Parasites Are Wiping Out Entire Honeybee Colonies – Magnitude Much Higher Than Previously Thought | Amazing Science | Scoop.it

Bees around the world are at risk from a number of threats including habitat loss and the effect of pesticides, plus bacterial disease like American foulbrood. Bee colonies are also at risk from mites and parasites, especially Varroa mite parasite. Although parasites have long been associated with “colony collapse disorder”, where entire hives are wiped out, it is only recently that the magnitude of the threat has been fully realised.


The parasite concerned is a microsporidian called Nosema ceranae, which can harm adult bees and their larvae. It causes adult bees to die early, and kills the larvae before they can transform into bees. It is spread easily via airborne spores.

The parasite poses a particular threat to honeybees found in Europe and across Asia. What is new, based on earlier investigations, is the risk to larvae. Most research had only detected infections occurring with adult bees.


The enhanced risks were found from studies conducted in a laboratory, where bees were kept and various risk scenarios involving the spread of the parasite were tried out. Under certain conditions, the scientists showed, entire colonies can be wiped out through parasitic infection.


Researchers have also found that infection is not easy to treat. Adult bees can be sprayed with the chemical fumagillin; however, when the effects wear off the infection can re-emerge.


Bees are of a great ecological importance (many agricultural crops worldwide are pollinated by honeybees), so researching why bees are in decline worldwide is of importance. The research into the parasitic risks is continuing.


The research was carried out at UC San Diego. The findings have been published in the journal PLOS One, in a paper titled “Nosema ceranae Can Infect Honey Bee Larvae and Reduces Subsequent Adult Longevity.”

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Dinosaurs wiped out rapidly 66 million years ago

Dinosaurs wiped out rapidly 66 million years ago | Amazing Science | Scoop.it

Dinosaurs flourished in Europe right up until the asteroid impact that wiped them out 66 million years ago, a new study shows. The theory that an asteroid rapidly killed off the dinosaurs is widely recognized, but until recently dinosaur fossils from the latest Cretaceous--the final stanza of dinosaur evolution--were known almost exclusively from North America. This has raised questions about whether the sudden decline of dinosaurs in the American and Canadian west was merely a local story.


The new study synthesizes a flurry of research on European dinosaurs over the past two decades. Fossils of latest Cretaceous dinosaurs are now commonly discovered in Spain, France, Romania, and other countries. By looking at the variety and ages of these fossils, a team of researchers led by Zoltán Csiki-Sava of the University of Bucharest'sFaculty of Geology and Geophysics has determined that dinosaurs remained diverse in European ecosystems very late into the Cretaceous.


In the Pyrenees of Spain and France, the best area in Europe for finding latest Cretaceous dinosaurs, meat and plant-eating species are present and seemingly flourishing during the final few hundred thousand years before the asteroid hit.


Dr Csiki-Sava said "For a long time, Europe was overshadowed by other continents when the understanding of the nature, composition and evolution of latest Cretaceous continental ecosystems was concerned. The last 25 years witnessed a huge effort across all Europe to improve our knowledge, and now we are on the brink of fathoming the significance of these new discoveries, and of the strange and new story they tell about life at the end of the Dinosaur Era."


Dr Steve Brusatte of the University of Edinburgh's School of GeoSciences (UK), an author on the report, added: "Everyone knows that an asteroid hit 66 million years ago and dinosaurs disappeared, but this story is mostly based on fossils from one part of the world, North America. We now know that European dinosaurs were thriving up to the asteroid impact, just like in North America. This is strong evidence that the asteroid really did kill off dinosaurs in their prime, all over the world at once."

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Uncovering diversity in an invisible ocean world

Uncovering diversity in an invisible ocean world | Amazing Science | Scoop.it

Plankton are vital to life on Earth — they absorb carbon dioxide, generate nearly half of the oxygen we breathe, break down waste, and are a cornerstone of the marine food chain. Now, new research indicates the diminutive creatures are not only more diverse than previously thought, but also profoundly affected by their environment.


Tara Oceans, an international consortium of researchers from MIT and elsewhere that has been exploring the world’s oceans in hopes of learning more about one of its smallest inhabitants, reported their initial findings this week in a special issue of Science. From 2009 to 2012, a small crew sailed on a 110-foot schooner collecting 35,000 samples of marine microbes and viruses from 200 locations around the globe — facing pirates, high winds, and ice storms in the process. But the effort was worth it. Among the studies’ findings: millions of new genes, thousands of new viruses, insights into microbial interactions, and ocean temperature's impact on species diversity.


The researchers identified 40 million genes in the upper ocean, most of which are new to science. In comparison, the human gut microbiome only has 10 million genes. Additionally, researchers identified more than 5,000 viruses, only 39 of which were known previously.


Underneath the ocean surface, viruses, plankton, and other microbes battle one another for survival. These interactions — which are mainly parasitic in nature — are vital for maintaining diversity, as they prevent one species from dominating the environment, the study's authors found. The expedition also revealed that species diversity is shaped by ocean temperature, which is on the rise. The new plethora of data should allow researchers to build predictive models that show how microbial communities will change in a warming world and its resulting impacts on oxygen production, carbon dioxide absorption, and ecosystem dynamics.


“The finding that temperature shapes which species are present, for instance, is especially relevant in the context of climate change, but to some extent this is just the beginning,” says Chris Bowler, a plant biologist from the French National Centre for Scientific Research. “The resources we’ve generated will allow us and others to delve even deeper, and finally begin to really understand the workings of this invisible world.”

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Toxin-absorbing nanosponges could be used to soak up localized infections

Toxin-absorbing nanosponges could be used to soak up localized infections | Amazing Science | Scoop.it

Back in 2013, we heard that nanoengineers at the University of California, San Diago (UC San Diego) had successfully used nanosponges to soak up toxins in the bloodstream. Fast-forward two years and the team is back with more nanospongey goodness, now using hydrogel to keep the tiny fellas in place, allowing them to tackle infections such as MRSA, without the need for antibiotics.


Let's start with a quick recap. In 2013, a team of researchers announced that they'd successfully managed to create nanosponges – nanoparticles coated in red blood cell membranes – that flow through the bloodstream, removing harmful toxins as they go. The red blood cell coating tricks the immune system into ignoring the nanoparticles, but the disguise also attracts pore-forming toxins that kill cells by perforating their outer membranes.


This breakthrough was ideal if you wanted to deal with harmful toxins in the bloodstream, such as snake venom, but it didn't allow for a sustained attack in a localized region. Since the initial announcement, the team has been working on improving the method, with the new study focusing on adapting it to clear up antibiotic-resistant bacterial infections.


In order to keep the nanosponges tied to a specific area, the team turned to hydrogel – a gel made of water and polymers. The team mixed the nanosponges into the hydrogel, which then holds them in place at an infected spot, allowing for all of the toxins to be removed.


Nanosponges are some three thousand times smaller than red blood cells, allowing billions to be held in every milliliter of hydrogel. The gel's pores are small enough to keep the nanosponges in, but also large enough to allow the toxins to pass through, making it an ideal agent for delivery of the treatment.


As the method doesn't involve antibiotics, it's thought that it won't be affected by existing bacterial antibiotic resistance, and the bacteria shouldn't develop any new resistance in response to the treatment.

The nanosponge/hydrogel combination was tested on MRSA-infected mice, with the team observing significantly smaller lesions on treated as opposed to untreated subjects. The tests also confirmed that hydrogel was effective at holding the nanosponges in place, with 80 percent remaining at the site of infection two days after being injected.

The UC San Diego researchers posted the results of their study in the journal Advanced Materials.


Via Jocelyn Stoller
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New Device Delivers Medicine One Molecule at a Time

New Device Delivers Medicine One Molecule at a Time | Amazing Science | Scoop.it

It's smaller than your index finger, and it might be the future of implantable devices to treat a fractured spine, pinched nerve, or neurological disorder like epilepsy.

As they report in the journal Science, a team of engineers and medical researchers in Sweden has just designed a pinpoint-accurate implantable drug pump. It delivers medicine with such precision that it requires only 1 percent of the drugs doctors would otherwise need to deploy. As it demonstrated in tests on seven rats, the tiny pump can attach directly to the spine (at the root of a nerve) and inject its medicine molecule by molecule.


"In theory, we could tell you exactly how many molecules our device is delivering," says Amanda Jonsson, the bio-electronical engineer at Sweden's Linköping University who led the team. "These very small dosages could help avoid drug side effects, or be useful for medicines that we simply can't use at larger doses."


The technology is based on a compact but complicated piece of laboratory equipment called an ion pump. To put it simply, as electric current enters the ion pump one electron at a time, medicine is flung out the other end one molecule at a time. One caveat: Because of this setup, only medicines that can be electrically charged can be used with the pump. But that includes more pain medicines than you might think, including morphine and other opiates.

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Human oral cavity contains 700 different species of bacteria but only 12 of them cause harm

Human oral cavity contains 700 different species of bacteria but only 12 of them cause harm | Amazing Science | Scoop.it

We nag our kids to brush their teeth well, but a few hours later, their mouths are just as full of bacteria as before they brushed..

Microbiologist Wenyuan Shi of UCLA thinks a sweet sucker might help lick the problem. Shi laments that while the cause of tooth decay is known to be an infection, dentistry today still uses a “mechanical” approach to disease. He says that there are 100 trillion bacteria in your mouth, consisting of 700 different species, but only 12 of those species cause any harm. One in particular, Streptococcus mutans, is a major factor in tooth decay.


“What we really try to do is to detect the pathogen who is responsible for the tooth decay, and treating the pathogen or get rid of the pathogen way before they are damaging the tooth,” says Shi. The challenge of that approach is that some of those bugs are actually beneficial. So Shi is working on ways to target the harmful bacteria while leaving the beneficial ones alone. “It’s like a dandelion infection in your lawn,” he says, “and if you use a general herbicide, you do kill the dandelion, but you kill the grass as well; and the moment you stop using your herbicide, who comes back first? It’s always the weeds.”


Shi looked to his Chinese roots for a traditional herbal remedy that targets only the bad bacteria. “We did a lot of the screening, and to our great surprise, one of the top hit we got out of the 2,000 medicinal herbs is licorice. And, as you know, many cultures have been chewing the licorice roots as a way to actually promoting oral health,” he says.


As they reported in the Journal of Natural Products, Shi’s team isolated the active compounds in licorice and showed they kill decay-causing bacteria in lab tests. With corporate partner C3-Jian, Inc., they developed an extract that would specifically combat S. mutansTo get the compounds into extended contact with teeth, they put them in a lollipop, manufactured and sold by Dr. John’s Candies, which specializes in sugar-free candy. The lollipops are orange flavored.


You can’t get the same effect from just eating licorice. Most licorice sold in the U.S. is actually flavored with anise. Plus it contains lots of sugar, which is bad for your teeth. Real licorice falls under the “generally recognized as safe” category by the FDA so the lollipops are already on the market, and starting to show up in dentists’ offices and pharmacies.

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Internet-of-Things Radio Chip Consumes Very Little Power to Save a Lot

Internet-of-Things Radio Chip Consumes Very Little Power to Save a Lot | Amazing Science | Scoop.it

At this year’s Consumer Electronics Show in Las Vegas, the big theme was the “Internet of things” — the idea that everything in the human environment, from kitchen appliances to industrial equipment, could be equipped with sensors and processors that can exchange data, helping with maintenance and the coordination of tasks.

Realizing that vision, however, requires transmitters that are powerful enough to broadcast to devices dozens of yards away but energy-efficient enough to last for months — or even to harvest energy from heat or mechanical vibrations.


“A key challenge is designing these circuits with extremely low standby power, because most of these devices are just sitting idling, waiting for some event to trigger a communication,” explains Anantha Chandrakasan, the Joseph F. and Nancy P. Keithley Professor in Electrical Engineering at MIT. “When it’s on, you want to be as efficient as possible, and when it’s off, you want to really cut off the off-state power, the leakage power.”


This week, at the Institute of Electrical and Electronics Engineers’ International Solid-State Circuits Conference, Chandrakasan’s group will present a new transmitter design that reduces off-state leakage 100-fold. At the same time, it provides adequate power for Bluetooth transmission, or for the even longer-range 802.15.4 wireless-communication protocol.


“The trick is that we borrow techniques that we use to reduce the leakage power in digital circuits,” Chandrakasan explains. The basic element of a digital circuit is a transistor, in which two electrical leads are connected by a semiconducting material, such as silicon. In their native states, semiconductors are not particularly good conductors. But in a transistor, the semiconductor has a second wire sitting on top of it, which runs perpendicularly to the electrical leads. Sending a positive charge through this wire — known as the gate — draws electrons toward it. The concentration of electrons creates a bridge that current can cross between the leads.


To generate the negative charge efficiently, the MIT researchers use a circuit known as a charge pump, which is a small network of capacitors — electronic components that can store charge — and switches. When the charge pump is exposed to the voltage that drives the chip, charge builds up in one of the capacitors. Throwing one of the switches connects the positive end of the capacitor to the ground, causing a current to flow out the other end. This process is repeated over and over. The only real power drain comes from throwing the switch, which happens about 15 times a second.


To make the transmitter more efficient when it’s active, the researchers adopted techniques that have long been a feature of work in Chandrakasan’s group. Ordinarily, the frequency at which a transmitter can broadcast is a function of its voltage. But the MIT researchers decomposed the problem of generating an electromagnetic signal into discrete steps, only some of which require higher voltages. For those steps, the circuit uses capacitors and inductors to increase voltage locally. That keeps the overall voltage of the circuit down, while still enabling high-frequency transmissions.


What those efficiencies mean for battery life depends on how frequently the transmitter is operational. But if it can get away with broadcasting only every hour or so, the researchers’ circuit can reduce power consumption 100-fold.

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Hydrographic Way to Add Intricate Color Pattern to 3-D Printed Creations

Hydrographic Way to Add Intricate Color Pattern to 3-D Printed Creations | Amazing Science | Scoop.it

Working with researchers at Zhejiang University in China, Changxi Zheng, assistant professor of computer science at Columbia Engineering, has developed a technique that enables hydrographic printing, a widely used industrial method for transferring color inks on a thin film to the surface of manufactured 3D objects, to color these surfaces with the most precise alignment ever attained. Using a new computational method they developed to simulate the printing process, Zheng and his team have designed a model that predicts color film distortion during hydrographic immersion, and uses it to generate a colored film that guarantees exact alignment of the surface textures to the object. The research will be presented at SIGGRAPH 2015, August 9 to 13, in Los Angeles.


"Attaining precise alignment of the color texture onto the surface of an object with a complex surface, whether it's a motorcycle helmet or a 3D-printed gadget, has been almost impossible in hydrographic printing until now," says Zheng. "By incorporating -- for the first time -- a computational model into the traditional hydrographic printing process, we've made it easy for anyone to physically decorate 3D surfaces with their own customized color textures."


Used in mass production for transferring repeated color patterns to a 3D surface, hydrographic printing can be applied to various materials including metal, plastic, wood, and porcelain. The process uses a PVA film with printed color patterns placed on top of water. An activator chemical is then sprayed on the film, softening the color film to make it easily stretchable. Next, a physical object is slowly dipped into the water through the floating film. Once the film touches the object, it gets stretched, wrapping the object's surface, and adhering to it. Throughout the process, the color ink printed on the PVA film is transferred to the surface. But the process has a fundamental limitation in that it is almost impossible to precisely align a color pattern to the object surface, because the object stretches the color film. With complex surfaces, the stretch can be severe and even tear the film apart.


"So current hydrographic printing has been limited to transferring repetitive color patterns," Zheng explains. "But there are many times when a user would like to color the surface of an object with particular color patterns, to decorate a 3D-printed mug with specific, personalized images or just to color a toy."


Building upon previous work on fluid and viscous sheet simulation also done at Columbia Computer Graphics Group, Zheng has developed a new viscous sheet simulation method to model the color film stretch during the hydrographic printing process. This model predicts the stretch and distortion of color films and creates a map between the locations on the film and the surface locations to which they are transferred. With the map, he can compute a color image for printing on the PVA film and then, after the hydrographic immersion, it forms the desired color pattern on the object's surface.

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The fly's neural compass works just like a mammal's

The fly's neural compass works just like a mammal's | Amazing Science | Scoop.it

Fruit flies have a neural compass that tracks orientation by combining visual and self-motion cues, according to a study published today in the journal Nature. The new research show that the compass in the fruit fly brain works in a similar way to that of mammals, suggesting that this tiny creature could teach us a few things about how our own compass works.


Most animals use landmarks to find their way around, but when navigating bare or unfamiliar terrain, they can estimate their position by tracking the direction and speed of their movements relative to a starting point, a process called path integration. The brains of rodents and other mammals contain at least four different types of nerve cells that are involved in this process, which co-operate to form a cognitive map of the surroundings.


Insects also use path integration. Honey bees perform a ‘waggle dance’ near the entrance to their nest to signal the direction, distance and abundance of a food source to their fellow workers, and foraging desert ants retrace their steps back to where they think their nest is, even after being picked up and moved, so that their trajectory is disrupted, on their outward journey. It’s widely believed that insects use simpler neural computations to navigate, and there’s very little evidence that they form cognitive maps.


In fruit flies, a ring-shaped brain structure called the ellipsoid body is needed for navigation. Johannes Seelig and Vivek Jayaraman of the Howard Hughes Medical Institute’s Janelia Research Campus in Ashburn, Virginia wanted to see how cells in this structure respond to visual stimuli, so designed an ingenious and tricky experiment to monitor the cells as the flies moved through a virtual reality environment.


First, they created genetically engineered fruit flies expressing a protein that fluoresces when nerve cells become active and the calcium level inside them rises. Then they attached individual flies to the end of a metal rod, placing them inside a circular screen displaying various lined patterns, with the laser beam of a powerful high-speed two-photon microscope focused into the ellipsoid body.


The flies were held in place over an air-suspended ball, and by running over this, they controlled the rotation of the screen, giving them the illusion of movement, with the horizontal and vertical stripes acting as landmarks along their virtual journey.


Seelig and Jarayaman noticed that the cells in the ellipsoid body itself tracked the fly’s orientation, producing ‘bumps’ of activity whose position around the ring-shaped structure corresponded to the direction of the stripes, and which rotated with the stripes as the flies turned the ball.


This compass-like neural activity continued when the flies were in the dark, using self-motion instead of visual cues, but became increasingly inaccurate with time. It even persisted for more than 30 seconds when the flies were removed from the ball and left standing in darkness, maybe forming a short-term memory of their orientation.


Reference

Seelig, J. D. & Jayaraman, V. (2015). Neural dynamics for landmark orientation and angular path integration. Nature521,186–191. DOI: 10.1038/nature14446


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This might explain why some politicians seem to have the mental capacity of a gnat!

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One step closer to single-molecule devices

One step closer to single-molecule devices | Amazing Science | Scoop.it

Columbia Engineering researchers have created the first single-molecule diode — the ultimate in miniaturization for electronic devices — with potential for real-world applications in electronic systems. The diode that has a high (>250) rectification and a high “on” current (~ 0.1 microamps), says Latha Venkataraman, associate professor of applied physics. “Constructing a device where the active elements are only a single molecule … which has been the ‘holy grail’ of molecular electronics, represents the ultimate in functional miniaturization that can be achieved for an electronic device,” he said.


With electronic devices becoming smaller every day, the field of molecular electronics has become ever more critical in solving the problem of further miniaturization, and single molecules represent the limit of miniaturization. The idea of creating a single-molecule diode was suggested by Arieh Aviram and Mark Ratner who theorized in 1974 that a molecule could act as a rectifier, a one-way conductor of electric current.


Researchers have since been exploring the charge-transport properties of molecules. They have shown that single-molecules attached to metal electrodes (single-molecule junctions) can be made to act as a variety of circuit elements, including resistors, switches, transistors, and, indeed, diodes. They have learned that it is possible to see quantum mechanical effects, such as interference, manifest in the conductance properties of molecular junctions.


Since a diode acts as an electricity valve, its structure needs to be asymmetric so that electricity flowing in one direction experiences a different environment than electricity flowing in the other direction. To develop a single-molecule diode, researchers have simply designed molecules that have asymmetric structures. “While such asymmetric molecules do indeed display some diode-like properties, they are not effective,” explains Brian Capozzi, a PhD student working with Venkataraman and lead author of the paper.


“A well-designed diode should only allow current to flow in one direction, and it should allow a lot of current to flow in that direction. Asymmetric molecular designs have typically suffered from very low current flow in both ‘on’ and ‘off’ directions, and the ratio of current flow in the two has typically been low. Ideally, the ratio of ‘on’ current to ‘off’ current, the rectification ratio, should be very high.”


To overcome the issues associated with asymmetric molecular design, Venkataraman and her colleagues — Chemistry Assistant Professor Luis Campos’ group at Columbia and Jeffrey Neaton’s group at the Molecular Foundry at UC Berkeley — focused on developing an asymmetry in the environment around the molecular junction. They created an environmental asymmetry through a rather simple method: they surrounded the active molecule with an ionic solution and used gold metal electrodes of different sizes to contact the molecule. Their results achieved rectification ratios as high as 250 — 50 times higher than earlier designs. The “on” current flow in their devices can be more than 0.1 microamps, which, Venkataraman notes, is a lot of current to be passing through a single-molecule. And, because this new technique is so easily implemented, it can be applied to all nanoscale devices of all types, including those that are made with graphene electrodes.

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A chip implanted under the skin allows for precise, real-time medical monitoring

A chip implanted under the skin allows for precise, real-time medical monitoring | Amazing Science | Scoop.it
It’s only a centimetre long, it’s placed under your skin, it’s powered by a patch on the surface of your skin and it communicates with your mobile phone. The new biosensor chip developed at EPFL is capable of simultaneously monitoring the concentration of a number of molecules, such as glucose and cholesterol, and certain drugs.
The future of medicine lies in ever greater precision, not only when it comes to diagnosis but also drug dosage. The blood work that medical staff rely on is generally a snapshot indicative of the moment the blood is drawn before it undergoes hours – or even days – of analysis.

Several EPFL laboratories are working on devices allowing constant analysis over as long a period as possible. The latest development is the biosensor chip, created by researchers in the Integrated Systems Laboratory working together with the Radio Frequency Integrated Circuit Group. Sandro Carrara is unveiling it today at the International Symposium on Circuits and Systems (ISCAS) in Lisbon.

Autonomous operation
“This is the world’s first chip capable of measuring not just pH and temperature, but also metabolism-related molecules like glucose, lactate and cholesterol, as well as drugs,” said Dr Carrara. A group of electrochemical sensors works with or without enzymes, which means the device can react to a wide range of compounds, and it can do so for several days or even weeks.

This one-centimetre square device contains three main components: a circuit with six sensors, a control unit that analyses incoming signals, and a radio transmission module. It also has an induction coil that draws power from an external battery attached to the skin by a patch. “A simple plaster holds together the battery, the coil and a Bluetooth module used to send the results immediately to a mobile phone,” said Dr Carrara.

Contactless, in vivo monitoring
The chip was successfully tested in vivo on mice at the Institute for Research in Biomedicine (IRB) in Bellinzona, where researchers were able to constantly monitor glucose and paracetamol levels without a wire tracker getting in the way of the animals’ daily activities. The results were extremely promising, which means that clinical tests on humans could take place in three to five years – especially since the procedure is only minimally invasive, with the chip being implanted just under the epidermis.

“Knowing the precise and real-time effect of drugs on the metabolism is one of the keys to the type of personalised, precision medicine that we are striving for,” said Dr Carrara.
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Medical ‘millirobots’ could replace invasive surgery

Medical ‘millirobots’ could replace invasive surgery | Amazing Science | Scoop.it

Using a “Gauss gun” principle, an MRI machine drives a “millirobot” through a hypodermic needle into your spinal cord and guides it into your brain to release life-threatening fluid buildup.


University of Houston researchers have developed a concept for MRI-powered millimeter-size “millirobots” that could one day perform unprecedented minimally invasive medical treatments. This technology could be used to treat hydrocephalus, for example. Current treatments require drilling through the skull to implant pressure-relieving shunts, said Aaron T. Becker, assistant professor of electrical and computer engineering at the University of Houston. But MRI scanners alone don’t produce enough force to pierce tissues (or insert needles). So the researchers drew upon the principle of the “Gauss gun.”


Here’s how the a Gauss gun works: a single steel ball rolls down a chamber, setting off a chain reaction when it smashes into the next ball, etc., until the last ball flies forward, moving much more quickly the initial ball. Based on that concept, the researchers imagine a medical robot with a barrel self-assembled from three small high-impact 3D-printed plastic components, with slender titanium rod spacers separating two steel balls.


Aaron T. Becker, assistant professor of electrical and computer engineering at the University of Houston, said the potential technology could be used to treat hydrocephalus and other conditions, allowing surgeons to avoid current treatments that require cutting through the skull to implant pressure-relieving shunts.


Becker was first author of a paper presented at ICRA, the conference of the IEEE Robotics and Automation Society, nominated for best conference paper and best medical robotics paper. “Hydrocephalus, among other conditions, is a candidate for correction by our millirobots because the ventricles are fluid-filled and connect to the spinal canal,” Becker said. “Our noninvasive approach would eventually require simply a hypodermic needle or lumbar puncture to introduce the components into the spinal canal, and the components could be steered out of the body afterwards.”


Future work will focus on exploring clinical context, miniaturizing the device, and optimizing material selection.

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New Shape-Shifting-Memory Metal Withstands 10 Million Transformations

New Shape-Shifting-Memory Metal Withstands 10 Million Transformations | Amazing Science | Scoop.it

In theory, shape-memory metals ought to be revolutionizing every corner of technology already, from the automotive industry to biotech. These futuristic metals—which can be bent and deformed but pop back to their original shape when heated or jolted with electricity—have already existed for decades. Until now, though, every shape-memory alloy has faced the same glaring issue: they wear out, and fast. Depending on the alloy, the metals will slowly lose their ability to change shape after just a few (or if you're lucky, a few thousand) transformations. That's kept the metals in the lab and out of your car or phone.


Today a team of German and American scientists have stumbled across an alloy of shape-memory metal that just won't quit—not even after being bent and reshaped an astonishing 10 million times, an unparalleled feat.


Manfred Wuttig, a material scientist at the University of Maryland who helped lead the team, said the metal's "fortuitous discovery," was part of a long, frustrating hunt for durable shape-memory metal. As Wuttig and his colleagues detail in a new paper in the journal Science, understanding the secret to this material's hardiness may open the floodgates to a new generation of shape-memory materials that make it into the real world.


"This really is a huge breakthrough, and could make shape-memory alloys much more widely used in everyday technology" says Richard James, a leading shape-memory materials scientist at the University of Minnesota, who was not involved in the research, "I've personally made many, many [shape-memory] alloys that have various super interesting properties, but no one would be able to use them as they last only a few cycles."


The new metal keeps its astounding durability, Wuttig and James agree that scientists now have a platform to test and create new hyper-durable shape-changing alloys. While Wuttig's new alloy was only created in a thin film measuring several hundred micrometers, "the next step is to scale this up into a bulk alloy. But I see no reason why this would be an issue."


This isn't just a steppingstone to bringing shape-shifting materials into everyday products (finally), James says. "We may even start to see all the various applications we've been dreaming about over the last few decades," like biomedical metallic heart-valves or hyper-efficient solar energy converters.

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Biodegradable computer chips made from wood

Biodegradable computer chips made from wood | Amazing Science | Scoop.it

Portable electronics -- typically made of non-renewable, non-biodegradable and potentially toxic materials -- are discarded at an alarming rate in consumers' pursuit of the next best electronic gadget.


In an effort to alleviate the environmental burden of electronic devices, a team of University of Wisconsin-Madison researchers has collaborated with researchers in the Madison-based U.S. Department of Agriculture Forest Products Laboratory (FPL) to develop a surprising solution: a semiconductor chip made almost entirely of wood.


The research team, led by UW-Madison electrical and computer engineering professor Zhenqiang "Jack" Ma, described the new device in a paper published today (May 26, 2015) by the journal Nature Communications. The paper demonstrates the feasibility of replacing the substrate, or support layer, of a computer chip, with cellulose nanofibril (CNF), a flexible, biodegradable material made from wood.


"The majority of material in a chip is support. We only use less than a couple of micrometers for everything else," Ma says. "Now the chips are so safe you can put them in the forest and fungus will degrade it. They become as safe as fertilizer." Zhiyong Cai, project leader for an engineering composite science research group at FPL, has been developing sustainable nanomaterials since 2009.


"If you take a big tree and cut it down to the individual fiber, the most common product is paper. The dimension of the fiber is in the micron stage," Cai says. "But what if we could break it down further to the nano scale? At that scale you can make this material, very strong and transparent CNF paper."


Working with Shaoqin "Sarah" Gong, a UW-Madison professor of biomedical engineering, Cai's group addressed two key barriers to using wood-derived materials in an electronics setting: surface smoothness and thermal expansion.


"You don't want it to expand or shrink too much. Wood is a natural hydroscopic material and could attract moisture from the air and expand," Cai says. "With an epoxy coating on the surface of the CNF, we solved both the surface smoothness and the moisture barrier."

Gong and her students also have been studying bio-based polymers for more than a decade. CNF offers many benefits over current chip substrates, she says.


"The advantage of CNF over other polymers is that it's a bio-based material and most other polymers are petroleum-based polymers. Bio-based materials are sustainable, bio-compatible and biodegradable," Gong says. "And, compared to other polymers, CNF actually has a relatively low thermal expansion coefficient."

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Nearly indestructible virus yields tool to treat diseases

Nearly indestructible virus yields tool to treat diseases | Amazing Science | Scoop.it

By unlocking the secrets of a bizarre virus that survives in nearly boiling acid, scientists at the University of Virginia School of Medicine have found a blueprint for battling human disease using DNA clad in near-indestructible armor. "What's interesting and unusual is being able to see how proteins and DNA can be put together in a way that's absolutely stable under the harshest conditions imaginable," said Edward H. Egelman, PhD, of the UVA Department of Biochemistry and Molecular Genetics. "We've discovered what appears to be a basic mechanism of resistance - to heat, to desiccation, to ultraviolet radiation. And knowing that, then, we can go in many different directions, including developing ways to package DNA for gene therapy."


The virus SIRV2 belongs to a common crenarchaeal virus family, the Rudiviridae. It was first discovered in 1998 in the hot acidic sulfurous springs of Iceland. According to previous studies, SIRV2 infects Sulfolobus islandicus, a single-celled microorganism that grows optimally at 80 degrees Celsius and at pH 3. The virus has a very stable rod-shaped viral capsule, about 900 nm long and 23 nm in width.


Now, Dr Prangishvili, Dr Egelman and their colleagues have used cryo-electron microscopy to generate a 3D reconstruction of the SIRV2 virion, which revealed a previously unknown form of virion organization.

The team identified surprising similarities between SIRV2 and the spores bacteria form to survive in inhospitable environments.


“Some of these spores are responsible for very, very horrific diseases that are hard to treat, like anthrax. So we show in this study that this virus actually functions in a similar way to some of the proteins present in bacterial spores,” said Dr Egeleman, who is the senior author on the paper published in the journal Science“Understanding how these bacterial spores work gives us potentially new abilities to destroy them,” he said.


Dr Egeleman and co-authors also found that SIRV2 survives the inhospitable conditions by forcing its DNA into what is called A-form, a structural state identified by pioneering DNA researcher Rosalind Franklin more than a half-century ago.


“This is, I think, going to highlight once again the contributions she made, because many people have felt that this A-form of DNA is only found in the laboratory under very non-biological conditions, when DNA is dehydrated or dry. Instead, it appears to be a general mechanism in biology for protecting DNA,” Dr Egelman said.

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New electronic stent could provide feedback and therapy—then dissolve

New electronic stent could provide feedback and therapy—then dissolve | Amazing Science | Scoop.it
Every year, an estimated half-million Americans undergo surgery to have a stent prop open a coronary artery narrowed by plaque. But sometimes the mesh tubes get clogged. Scientists report in the journal ACS Nano a new kind of multi-tasking stent that could minimize the risks associated with the procedure. It can sense blood flow and temperature, store and transmit the information for analysis and can be absorbed by the body after it finishes its job.


Doctors have been implanting stents to unblock coronary arteries for 30 years. During that time, the devices have evolved from bare metal, mesh tubes to coated stents that can release drugs to prevent reclogging. But even these are associated with health risks. So researchers have been working on versions that the body can absorb to minimize the risk that a blood clot will form. And now Dae-Hyeong Kim, Seung Hong Choi, Taeghwan Hyeon and colleagues are taking that idea a step further.


The researchers developed and tested in animals a drug-releasing electronic stent that can provide diagnostic feedback by measuring blood flow, which slows when an artery starts narrowing. The device can also heat up on command to speed up drug delivery, and it can dissolve once it's no longer needed.


More information: Bioresorbable Electronic Stent Integrated with Therapeutic Nanoparticles for Endovascular Diseases Bioresorbable Electronic Stent Integrated with Therapeutic Nanoparticles for Endovascular Diseases, ACS Nano, Article ASAP. DOI: 10.1021/acsnano.5b00651

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First-ever 3D human heart simulator may lead to better treatments

First-ever 3D human heart simulator may lead to better treatments | Amazing Science | Scoop.it

A French company better known for designing aircraft systems announced Wednesday that, on May 29, it will release the world’s first commercially available, scientifically accurate, simulated 3-dimensional (3D) model of a whole, healthy heart. The model may, with fine-tuning and additional development, help to revolutionize the way that cardiologists match treatments to individual heart patients.


The culmination of the first phase of Dassault Systemes' “Living Heart Project,” the simulation may soon allow physicians, medical device manufacturers and others to understand disease states and test innovative treatments without resorting to animal testing.


According to Living Heart Project director Steve Levine, it will soon be possible for cardiologists to rehearse difficult procedures using the company’s 3D modeling. Starting on May 29, when the heart model is released, doctors can use the baseline healthy heart to study congenital defects or heart disease by modifying the shape and tissue properties through the use of a software editor.


Levine says that doctors have developed models and simulations of different sections of the heart, but until now, no one had been able to put these pieces together into an holistic simulation.


“What we can now do for devices that go inside the heart is you can test it on the computer the same way you can test planes,” Levine told Mashable in an interview. The project involves 45 medical professionals, organizations and regulatory agencies, including the Food and Drug Administration (FDA), which oversees the U.S. medical industry. The FDA signed a five-year collaborative research agreement with Dassault to help oversee the development of a heart model that can be used for regulatory science.


Via Luca Baptista
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Phase III Virotherapy uses modified herpes virus to attack melanoma cells

Phase III Virotherapy uses modified herpes virus to attack melanoma cells | Amazing Science | Scoop.it

Patients with aggressive skin cancer - melanoma - have been treated successfully using a drug based on the herpes virus, in a trial that could pave the way for a new generation of cancer treatments. The findings mark the first positive phase 3 trial results for cancer “virotherapy”, where one disease is harnessed and used to attack another. If approved, the drug, called T-VEC, could be more widely available for cancer patients by next year, scientists predicted.


Crucially, the therapy has the potential to overcome cancer even when the disease has spread to organs throughout the body, offering hope in future to patients who have been faced with the bleakest prognosis. Kevin Harrington, professor of biological cancer therapies at the Institute of Cancer Research London, who led the work, said: “This is the big promise of this treatment. It’s the first time a virotherapy has been shown to be successful in a phase 3 trial.”


In the trial, involving more than 400 patients with aggressive melanoma, one in four patients responded to the treatment, and 16% were still in remission after six months. About 10% of the patients treated had “complete remission”, with no detectable cancer remaining - considered a cure if the patient is still cancer-free five years after diagnosis.


The results are especially encouraging, Harrington said, because all the patients had inoperable, relapsed or metastatic melanoma with no conventional treatment options available to them. “They had disease that ranged from dozens to hundreds of deposits of melanoma on a limb all the way to patients where cancer had spread to the lungs and liver,” he said.

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Beyond Moore's law: Even after Moore’s law ends, chip costs could still halve every few years

Beyond Moore's law: Even after Moore’s law ends, chip costs could still halve every few years | Amazing Science | Scoop.it

There is a popular misconception about Moore’s law (that the number of transistors on a chip doubles every two years) which has led many to conclude that the 50-year-old prognostication is due to end shortly. This doubling of processing power, for the same cost, has continued apace since Gordon Moore, one of Intel's founders, observed the phenomenon in 1965. At the time, a few hundred transistors could be crammed on a sliver of silicon. Today’s chips can carry billions.


Whether Moore’s law is coming to an end is moot. As far as physical barriers to further shrinkage are concerned, there is no question that, having been made smaller and smaller over the decades, crucial features within transistors are approaching the size of atoms. Indeed, quantum and thermodynamic effects that occur at such microscopic dimensions have loomed large for several years.


Until now, integrated circuits have used a two-dimensional (planar) structure, with a metal gate mounted across a flat, conductive channel of silicon. The gate controls the current flowing from a source electrode at one end of the channel to a drain electrode at the other end. A small voltage applied to the gate lets current flow through the transistor. When there is no voltage on the gate, the transistor is switched off. These two binary states (on and off) are the ones and zeros that define the language of digital devices.


However, when transistors are shrunk beyond a certain point, electrons flowing from the source can tunnel their way through the insulator protecting the gate, instead of flowing direct to the drain. This leakage current wastes power, raises the temperature and, if excessive, can cause the device to fail. Leakage becomes a serious problem when insulating barriers within transistors approach thicknesses of 3 nanometres (nm) or so. Below that, leakage increases exponentially, rendering the device pretty near useless.


Intel, which sets the pace for the semiconductor industry, started preparing for the leakage problem several “nodes” (changes in feature size) ago. At the time, it was still making 32nm chips. The solution adopted was to turn a transistor’s flat conducting channel into a vertical fence (or fin) that stood proud of the substrate. Instead of just one small contact patch, this gave the gate straddling the fence three contact areas (a large one on either side of the fence and a smaller one across the top). With more control over the current flowing through the channel, leakage is reduced substantially. Intel reckons “Tri-Gate” processors switch 37% faster and use 50% less juice than conventional ones.


Having introduced the Tri-Gate transistor design (now known generically as FinFET) with its 22nm node, Intel is using the same three-dimensional architecture in its current 14nm chips, and expects to do likewise with its 10nm ones, due out later this year and in mainstream production by the middle of 2016. Beyond that, Intel says it has some ideas about how to make 7nm devices, but has yet to reveal details. The company’s road map shows question marks next to future 7nm and 5nm nodes, and peters out shortly thereafter.


At a recent event celebrating the 50th anniversary of Moore’s law, Intel’s 86-year-old chairman emeritus said his law would eventually collapse, but that “good engineering” might keep it afloat for another five to ten years. Mr Moore was presumably referring to further refinements in Tri-Gate architecture. No doubt he was also alluding to advanced fabrication processes, such as “extreme ultra-violet lithography” and “multiple patterning”, which seemingly achieve the impossible by being able to print transistor features smaller than the optical resolution of the printing system itself.

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Google Tests First Error Correction in Quantum Computing

Google Tests First Error Correction in Quantum Computing | Amazing Science | Scoop.it

Quantum computers won’t ever outperform today’s classical computers unless they can correct for errors that disrupt the fragile quantum states of their qubits. A team at Google has taken the next huge step toward making quantum computing practical by demonstrating the first system capable of correcting such errors.


Google’s breakthrough originated with the hiring of a quantum computing research group from the University California, Santa Barbara in the autumn of 2014. The UCSB researchers had previously built a system of superconducting quantum circuits that performed with enough accuracy tomake error correction a possibility. That earlier achievement paved the way for the researchers—many now employed at Google—to build a system that can correct the errors that naturally arise during quantum computing operations. Their work is detailed in the 4 March 2015 issue of the journal Nature.


“This is the first time natural errors arising from the qubit environment were corrected,” said Rami Barends, a quantum electronics engineer at Google. “It’s the first device that can correct its own errors.”


Quantum computers have the potential to perform many simultaneous calculations by relying upon quantum bits, or qubits, that can represent information as both 1 and 0 at the same time. That gives quantum computing a big edge over today’s classical computers that rely on bits that can only represent either 1 or 0.


But a huge challenge in building practical quantum computers involves preserving the fragile quantum states of qubits long enough to run calculations. The solution that Google and UCSB have demonstrated is a quantum error-correction code that uses simple classical processing to correct the errors that arise during quantum computing operations.


Such codes can’t directly detect errors in qubits without disrupting the fragile quantum states. But they get around that problem by relying on entanglement, a physics phenomenon that enables a single qubit to share its information with many other qubits through a quantum connection. The codes exploit entanglement with an architecture that includes “measurement” qubits entangled with neighboring “data” qubits.


The Google and UCSB team has been developing a specific quantum error-correction code called “surface code.” They eventually hope to build a 2-D surface code architecture based on a checkerboard arrangement of qubits, so that “white squares” would represent the data qubits that perform operations and “black squares” would represent measurement qubits that can detect errors in neighboring qubits.


For now, the researchers have been testing the surface code in a simplified “repetition code” architecture that involves a linear, 1-D array of qubits. Their unprecedented demonstration of error correction used a repetition code architecture that included nine qubits. They tested the repetition code through the equivalent of 90,000 test runs to gather the necessary statistics about its performance.

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Investors Europe Stock Brokers's curator insight, May 23, 2:25 AM

Quantum computers have the potential to perform many simultaneous calculations by relying upon quantum bits, or qubits, that can represent information as both 1 and 0 at the same time. That gives quantum computing a big edge over today’s classical computers that rely on bits that can only represent either 1 or 0.


But a huge challenge in building practical quantum computers involves preserving the fragile quantum states of qubits long enough to run calculations. The solution that Google and UCSB have demonstrated is a quantum error-correction code that uses simple classical processing to correct the errors that arise during quantum computing operations.

Pablo Vicente Munuera's curator insight, May 23, 4:05 AM

Quantum computers are coming... :D

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Most Luminous Known Galaxy Shines Brighter Than Light of 300 Trillion Suns

Most Luminous Known Galaxy Shines Brighter Than Light of 300 Trillion Suns | Amazing Science | Scoop.it

NASA researchers have identified the brightest galaxy ever encountered, which shines in the infrared wavelength with the equivalent light of 300 trillion suns. This "extremely luminous infrared galaxy" was encountered in data from 2010's Wide-field Infrared Survey Explorer. The WISE space telescope has revealed a number of strange and unique galaxies. This one, the astronomers theorize, may have a supermassive black hole at the center, which draws immense amounts of gas and matter into itself and releases a veritable rainbow of electromagnetic energy. This energy, however, is blocked by thick a halo of dust, which absorbs it and heats up, emitting infrared light instead — and in unprecedented amounts.


What's more, this particular galaxy is so far away that the light we're receiving from Earth was given off some 12.5 billion years ago. That means it grew that large and that bright during the infancy of the universe itself. To the researchers, that suggests that the black hole forming the center of the galaxy is breaking the rules somehow: It may have simply started out bigger than any we've encountered, or it might have grown faster than we believed possible.


"Another way for a black hole to grow this big is for it to have gone on a sustained binge, consuming food faster than typically thought possible," said the University of Leicester's Andrew Blain, co-author of the report describing the galaxy, in a NASA news release.


Understanding the galaxy's formation will help shed light on the early history of the universe, and set a precedent for studying similar objects. The report appears in the May 22 issue of The Astrophysical Journal, and can be read on Arxiv.

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Ice loss in Antarctica so large that it affects Earth's gravity field

Ice loss in Antarctica so large that it affects Earth's gravity field | Amazing Science | Scoop.it

A group of scientists, led by a team from the University of Bristol, UK has observed a sudden increase of ice loss in a previously stable region of Antarctica. The research is published today in ScienceUsing measurements of the elevation of the Antarctic ice sheet made by a suite of satellites, the researchers found that the Southern Antarctic Peninsula showed no signs of change up to 2009. Around 2009, multiple glaciers along a vast coastal expanse, measuring some 750km in length, suddenly started to shed ice into the ocean at a nearly constant rate of 60 cubic km, or about 55 trillion litres of water, each year.


This makes the region the second largest contributor to sea level rise in Antarctica and the ice loss shows no sign of waning. Dr Bert Wouters, a Marie Curie Fellow at the University of Bristol, who lead the study said: "To date, the glaciers added roughly 300 cubic km of water to the ocean. That's the equivalent of the volume of nearly 350,000 Empire State Buildings combined."


The changes were observed using the CryoSat-2 satellite, a mission of the European Space Agency dedicated to remote-sensing of ice. From an altitude of about 700km, the satellite sends a radar pulse to Earth, which is reflected by the ice and subsequently received back at the satellite. From the time the pulse takes to travel, the elevation of the ice surface can retrieved with incredible accuracy. By analysing roughly 5 years of the data, the researchers found that the ice surface of some of the glaciers is currently going down by as much as 4m each year.

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