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Unavoidable disorder used to build nanolaser

Unavoidable disorder used to build nanolaser | Amazing Science | Scoop.it

Researchers the world round are working to develop optical chips, where light can be controlled with nanostructures. These could be used for future circuits based on light (photons) instead of electron - that is photonics instead of electronics. But it has proved to be impossible to achieve perfect photonic nanostructures: they are inevitably a little bit imperfect. Now researchers at the Niels Bohr Institute in collaboration with DTU have discovered that imperfect nanostructures can offer entirely new functionalities. They have shown that imperfect optical chips can be used to produce 'nanolasers', which is an ultimately compact and energy-efficient light source. The results are published in the scientific journal Nature Nanotechnology.


The researchers are working with extremely small photonic crystal membranes - the width of the membrane is 25 micrometer, and the thickness is 340 nanometers (1 nanometer is one thousandth of a micrometer). The crystals are made of the semiconducting material gallium arsenide (GaAs). A pattern of holes are etched into the material at a regular distance of 380 nanometers. The holes have the function of acting as built-in mirrors that reflect the light and can thus be used to control the spread of the light in the optical chip. The researchers have therefore tried to achieve as perfect a regular structure of holes as possible to control the light in certain optical circuit.


"It turns out that the imperfect optical chips are extremely well suited for capturing light. When the light is sent into the imperfect chip, it will hit the many small irregular holes, which reflect the light in random directions. Due to the frequent reflections, the light is spontaneously captured in the nanostructure and cannot escape. This allows the light to be amplified, resulting in surprisingly good conditions for creating highly efficient and compact lasers," explains Peter Lodahl, professor and head of the Quantum Photonic research group at the Niels Bohr Institute at the University of Copenhagen.

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Plasmonic pixels could be used to make non-fading paint

Plasmonic pixels could be used to make non-fading paint | Amazing Science | Scoop.it

Researchers are developing a technology that could one day make paint and color packaging labels that never fade. The color is produced by a type of nanostructure called a "plasmonic pixel."

 

In a new paper published in Nano Letters, Timothy D. James, Paul Mulvaney, and Ann Roberts at The University of Melbourne have demonstrated a new plasmonic pixel design that addresses several of the critical problems facing plasmonic color images, including a limited number of colors, small image size, and difficulty in creating accurate colors without using complex color-mapping algorithms.

 

The new plasmonic pixel design uses an algorithm that can produce nearly 2000 different colors and shades and achieve a resolution that exceeds the resolution limit of the human eye. To demonstrate, the researchers fabricated a 1.5-cm-long image (which is relatively large compared to previous plasmonic images), and showed that colors could be accurately reproduced using a straightforward color-mapping algorithm.

Although other areas of plasmonics research may have potential applications as displays for phones and TVs, this plasmonic pixel produces a static image, where the color and structure are set at the time of fabrication and can't be altered.

 

"The potential applications for the plasmonic pixel (and other color-producing nanostructures in this research space) would be as an industrial paint on cars, buildings, advertising billboards, etc., as the plasmonic pixels will never fade," James told Phys.org. "With the ability to print at resolutions greater than conventional pigment-based processes, the plasmonic pixels may also have applications in security-based devices for use on high-value product packaging, medicines, etc."

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New battery breakthrough that could change energy storage forever

New battery breakthrough that could change energy storage forever | Amazing Science | Scoop.it

Creating batteries with longer life span could be key in tech advancements from phones to cars.

 

Researchers now coated a gold nanowire with Thai's gel solution and found that the nanowire-based battery cell had far better storage capacity than typical lithium ion batteries. The gel electrode went through 200,000 charge cycles over three months without losing any capacity or power. For reference, batteries typically die after 5,000 to 7,000 cycles. The gel solution was published in the American Chemical Society’s Energy Letters.

 

"For this research right now the plan is to understand the mechanisms of how this gel electrolyte could prolong the cyclibility so well," Thai said. "The future bigger plan would be to optimize these gel electrolytes to see if it can improve even more."

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DNA "tape recorder" that can trace the family history of every cell in a body

DNA "tape recorder" that can trace the family history of every cell in a body | Amazing Science | Scoop.it

Researchers have invented a DNA "tape recorder" that can trace the family history of every cell in an organism. The technique is being hailed as a breakthrough in understanding how the trillions of complex cells in a body are descended from a single egg.

"It has the potential to provide profound insights into how normal, diseased or damaged tissues are constructed and maintained," one UK biologist told the BBC. The work appears in Science journal.

 

The human body has around 40 trillion cells, each with a highly specialized function. Yet each can trace its history back to the same starting point - a fertilized egg. Developmental biology is the business of unravelling how the genetic code unfolds at each cycle of cell division, how the body plan develops, and how tissues become specialized. But much of what it has revealed has depended on inference rather than a complete cell-by-cell history.

 

"I actually started working on this problem as a graduate student in 2000," confessed Jay Shendure, lead researcher on the new scientific paper. "Could we find a way to record these relationships between cells in some compact form we could later read out in adult organisms?"

 

The project failed then because there was no mechanism to record events in a cell's history. That changed with recent developments in so called CRISPR gene editing, a technique that allows researchers to make much more precise alterations to the DNA in living organisms. The molecular tape recorder developed by Prof Shendure's team at the University of Washington in Seattle, US, is a length of DNA inserted into the genome that contains a series of edit points which can be changed throughout an organism's life. Each edit records a permanent mark on the tape that is inherited by all of a cell's descendants. By examining the number and pattern of all these marks in an adult cell, the team can work back to find its origins. Developmental biologist James Briscoe of the Crick Institute, in London, UK, calls it "a creative and exciting use" of the CRISPR technique.

 

"It uniquely and indelibly marks cells with a 'barcode' that is inherited in the DNA. This means you can use the barcode to trace all the progeny of barcoded cells," he said. Jay Shendure collaborated with molecular biologist Alex Schier of Harvard University to prove the technique on a classic lab organism - the zebrafish.

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Strange sea-dwelling reptile fossil hints at rapid evolution after mass extinction

Strange sea-dwelling reptile fossil hints at rapid evolution after mass extinction | Amazing Science | Scoop.it

Two hundred and fifty million years ago, life on earth was in a tail-spin—climate change, volcanic eruptions, and rising sea levels contributed to a mass extinction that makes the death of the dinosaurs look like child's play.

 

In a paper published in Scientific Reports, paleontologists describe a new marine reptile, Sclerocormus parviceps, an ichthyosauriform that's breaking all the rules about what ichthyosaurs are like.

 

Ichthyosaurs were a massive group of marine reptiles that lived around the time of the earliest dinosaurs. Most of them looked a little bit like today's dolphins—streamlined bodies, long beak-like snouts, and powerful tail fins. But the new species is something of a black sheep. It has a short snout (its species name even means "small skull"), and instead of a tail with triangular flukes (think of a fish's tail-fins), it had a long, whip-like tail without big fins at the end. And while many ichthyosaurs had conical teeth for catching prey, Sclerocormus was toothless and instead seems to have used its short snout to create pressure and suck up food like a syringe. In short, it's really different from most of its relatives, and that tells scientists something important about evolution.

 

"Sclerocormus tells us that ichthyosauriforms evolved and diversified rapidly at the end of the Lower Triassic period," explains Olivier Rieppel, The Field Museum's Rowe Family Curator of Evolutionary Biology. "We don't have many marine reptile fossils from this period, so this specimen is important because it suggests that there's diversity that hasn't been uncovered yet."

 

The way this new species evolved into such a different form so quickly sheds light on how evolution actually works. "Darwin's model of evolution consists of small, gradual changes over a long period of time, and that's not quite what we're seeing here. These ichthyosauriforms seem to have evolved very quickly, in short bursts of lots of change, in leaps and bounds," says Rieppel.

 

Animals like Sclerocormus that lived just after a mass extinction also reveal how life responds to huge environmental pressures. "We're in a mass extinction right now, not one caused by volcanoes or meteorites, but by humans," explains Rieppel. "So while the extinction 250 million years ago won't tell us how to solve what's going on today, it does bear on the evolutionary theory at work. How do we understand the recovery and rebuilding of a food chain, of an ecosystem? How does that get fixed, and what comes first?"

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New in-ear device could be the beginning of a world without language barriers

New in-ear device could be the beginning of a world without language barriers | Amazing Science | Scoop.it

From Gene Roddenberry in Star Trek to Douglas Adams in The Hitchhiker’s Guide to the Galaxy, anyone who spends much time forecasting the future comes to realize that language has simply got to go. In a connected world, it’s one of the only things remaining that truly separates us — it’s what keeps keeps us from being able to directly consume and understand one another’s film and literature, and what keeps occupying soldiers from being able to effectively make alliances with local peoples. It’s a primitive relic of a bygone age — if we can convert MP4 to AVI, certainly we ought to be able to convert Mandarin to German. Now, a new device called Pilot could make that dream (mostly) a reality.

 

A real-world Babelfish, or Universal Translator if you prefer, has been slow to materialize. We’ve got speech recognition, and we’ve got translation, and we’ve even got both of those things in real-time in some very specific cases, but a portable, near-real-time translation device that moves with you? Despite rumors of GoogleX super-projects, it hasn’t happened yet.

 

One big reason is that real-time translation is hard. It’s so hard, in fact, that all the advancement in computing power we’ve seen in the past 20 years did little to get us closer to the goal. It took a revolution in how we compute information, the influx of neural network models and machine learning algorithms, before we could crunch natural language and produce a translation in a reasonable amount of time — but there’s still a problem. Neural networks are themselves very hard to run, meaning we need a super-computer to do translation.

 

In the context of a wearable, that means you’ll probably need an always-on data connection, which itself means you’ll need a subscription and a hefty power supply to keep the connection going all day. Pilot gets around this by wirelessly accessing your cell phone’s processor to do the work locally; prior on-phone translation services have been imperfect, but Pilot claims to have reached true real-time speeds.

 

What this does to your cellphone’s battery is anybody’s guess, but I’d bet this sort of intensive crunching would burn through even giant Galaxy S-series batteries in a short time. It’s not exactly living “untethered” if you have to plug your phone in every 45 minutes, but sci-fi beggars can’t be choosers, and the early adopters who buy one of these for a cool $300 will still be able to feel like they’re legitimately at the forefront of a tech revolution.

 

The other problem that has held back universal translators is that making one is a complex challenge many practical concerns. Do you turn it on only when you need it, and if so aren’t you going to miss a lot of the unexpected banter that you’d want to hear? How does it know who you’re talking to, in a crowded room full of people speaking? How does it fit on my damn head?

 

Pilot gets around these problems by splitting the service into two pieces. It’s not actually an earpiece, but two earpieces. When you’ve decided you want to talk to somebody (like the dreamy French girl who allegedly inspired this thing), you simply hand them their ear-piece to begin talking. Each of you now has a translator, so you can both understand one another — this takes the place of any sort of speaker that most sci-fi translators use to say our words out loud.

 

So, it’s not quite a “put it in your ear and it’s like everyone’s speaking English” super-invention, and since this came out of an Indiegogo campaign, you wouldn’t really expect it to. But it is incredibly ambitious, and it could spark existing translation efforts from Skype (Microsoft) and Google to shoot a little higher, a little faster.

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Dubai unveils world's first 3D-printed office building

Dubai unveils world's first 3D-printed office building | Amazing Science | Scoop.it

The world's first 3D-printed office building opened this week in DubaiReuters reports. The 2,700-square-foot, single-story building was built in just 17 days using a gigantic, 20-foot tall 3D printer and a special mix of concrete, fiber reinforced plastic and glass fiber reinforced gypsum.

 

Although the "printer" was massive at about two stories tall, 120 feet long and 40 feet wide, it only needed one staffer to make sure it was functioning properly. The rest of the 18-person construction crew consisted of installers, electricians and mechanical engineers who completed the job for a mere $140,000 in construction and labor costs — or about half the price of a comparable structure built with conventional methods. Of course, the building is more than just another gold star in the UAE's ultramodern playland — it will also serve, appropriately enough, as the temporary headquarters for the Dubai Future Foundation. Next year, the structure is scheduled to become the home of Dubai's Museum of the Future.

 

"This is the first 3D-printed building in the world, and it's not just a building, it has fully functional offices and staff," the UAE Minister of Cabinet Affairs, Mohamed Al Gergawi said. According to Gergawi, Dubai plans to have 25 percent of the buildings in the emirate built via 3D printing by the year 2030.

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Airbus Released World's First Functional 3D Printed Motorcycle

Airbus Released World's First Functional 3D Printed Motorcycle | Amazing Science | Scoop.it

Airbus subsidiary APWorks just announced its creation of the world’s first fully-functional 3D printed motorcycle. Printed using APWorks’ patented materials and techniques, the motorcycle weighs only 35 kg. Nicknamed the “Light Rider,” this new design is certainly lightweight: it is 30% lighter than conventionally manufactured e-motorcycles, with a 6 kg frame and a small 6 kW electric motor powering it from zero to 80 km per hour in just seconds.

 

The design makes full use of 3D printing technology. It has hollow frame parts instead of solid ones, allowing for integrated cables, pipes and screw-on points in the final structure. The printing system melts millions of aluminum alloy particles together creating thousands of thin layers just 60 microns thick.

 

To make the Light Rider, the company used their own proprietary material, Scalmalloy, for the construction of the frame. Scalmalloy is a corrosion-resistant aluminum alloy that is virtually as strong as titanium, boasting high strength and ductility

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The first ever photograph of light as both a particle and wave

The first ever photograph of light as both a particle and wave | Amazing Science | Scoop.it

(Phys.org)—Light behaves both as a particle and as a wave. Since the days of Einstein, scientists have been trying to directly observe both of these aspects of light at the same time.

 

Quantum mechanics tells us that light can behave simultaneously as a particle or a wave. However, there has never been an experiment able to capture both natures of light at the same time; the closest we have come is seeing either wave or particle, but always at different times. Taking a radically different experimental approach, EPFL scientists have now been able to take the first ever snapshot of light behaving both as a wave and as a particle. The breakthrough work is published in Nature Communications.

 

When UV light hits a metal surface, it causes an emission of electrons. Albert Einstein explained this "photoelectric" effect by proposing that light – thought to only be a wave – is also a stream of particles. Even though a variety of experiments have successfully observed both the particle- and wave-like behaviors of light, they have never been able to observe both at the same time.

 

A research team led by Fabrizio Carbone at EPFL has now carried out an experiment with a clever twist: using electrons to image light. The researchers have captured, for the first time ever, a single snapshot of light behaving simultaneously as both a wave and a stream of particles.

 

The experiment is set up like this: A pulse of laser light is fired at a tiny metallic nanowire. The laser adds energy to the charged particles in the nanowire, causing them to vibrate. Light travels along this tiny wire in two possible directions, like cars on a highway. When waves traveling in opposite directions meet each other they form a new wave that looks like it is standing in place. Here, this standing wave becomes the source of light for the experiment, radiating around the nanowire.

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Two-hundred-terabyte maths proof is largest ever, larger than US Library of Congress

Two-hundred-terabyte maths proof is largest ever, larger than US Library of Congress | Amazing Science | Scoop.it
Three computer scientists have announced the largest-ever mathematics proof: a file that comes in at a whopping 200 terabytes1, roughly equivalent to all the digitized text held by the US Library of Congress. The researchers have created a 68-gigabyte compressed version of their solution — which would allow anyone with about 30,000 hours of spare processor time to download, reconstruct and verify it — but a human could never hope to read through it.

Computer-assisted proofs too large to be directly verifiable by humans have become commonplace, and mathematicians are familiar with computers that solve problems in combinatorics — the study of finite discrete structures — by checking through umpteen individual cases. Still, “200 terabytes is unbelievable”, says Ronald Graham, a mathematician at the University of California, San Diego. The previous record-holder is thought to be a 13-gigabyte proof2, published in 2014.

The puzzle that required the 200-terabyte proof, called the Boolean Pythagorean triples problem, has eluded mathematicians for decades. In the 1980s, Graham offered a prize of US$100 for anyone who could solve it. (He duly presented the cheque to one of the three computer scientists, Marijn Heule of the University of Texas at Austin, earlier this month.) The problem asks whether it is possible to colour each positive integer either red or blue, so that no trio of integers a, b and c that satisfy Pythagoras’ famous equation a2 + b2 = c2 are all the same colour. For example, for the Pythagorean triple 3, 4 and 5, if 3 and 5 were coloured blue, 4 would have to be red.

In a paper posted on the arXiv server on 3 May, Heule, Oliver Kullmann of Swansea University, UK, and Victor Marek of the University of Kentucky in Lexington have now shown that there are many allowable ways to colour the integers up to 7,824 — but when you reach 7,825, it is impossible for every Pythagorean triple to be multicoloured1. There are more than 102,300 ways to colour the integers up to 7,825, but the researchers took advantage of symmetries and several techniques from number theory to reduce the total number of possibilities that the computer had to check to just under 1 trillion. It took the team about 2 days running 800 processors in parallel on the University of Texas’s Stampede supercomputer to zip through all the possibilities. The researchers then verified the proof using another computer program.
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Possible case for fifth force of nature

Possible case for fifth force of nature | Amazing Science | Scoop.it

A team of physicists at the University of California has uploaded a paper to the arXiv preprint server in which they suggest that work done by a team in Hungary last year might have revealed the existence of a fifth force of nature. Their paper has, quite naturally, caused quite a stir in the physics community as several groups have set a goal of reproducing the experiments conducted by the team at the Hungarian Academy of Science's Institute for Nuclear Research.

 

The work done by the Hungarian team, led by Attila Krasznahorkay, examined the possible existence of dark photons—the analog of conventional photons but that work with dark matter. They shot protons at lithium-7 samples creating beryllium-8 nuclei, which, as it decayed, emitted pairs of electrons and positrons. Surprisingly, as they monitored the emitted pairs, instead of a consistent drop-off, there was a slight bump, which the researchers attributed to the creation of an unknown particle with a mass of approximately 17 MeV. The team uploaded their results to the arXiv server, and their paper was later published by Physical Review Letters. It attracted very little attention until the team at UoC uploaded their own paper suggesting that the new particle found by the Hungarian team was not a dark photon, but was instead possibly a protophobic X boson, which they further suggested might carry a super-short force which acts over just the width of an atomic nucleus—which would mean that it is a force that is not one of the four described as the fundamental forces that underlie modern physics.

 

The paper uploaded by the UoC team has created some excitement, as well as public exclamations of doubt—reports of the possibility of a fifth force of nature have been heard before, but none have panned out. But still, the idea is intriguing enough that several teams have announced plans to repeat the experiments conducted by the Hungarian team, and all eyes will be on the DarkLight experiments at the Jefferson Laboratory, where a team is also looking for evidence of dark photons—they will be shooting electrons at gas targets looking for anything with masses between 10 and 100 MeV, and now more specifically for those in the 17 MeV region. What they find, or don't, could prove whether an elusive fifth force of nature actually exists, within a year's time.

 

More information: arxiv.org/pdf/1604.07411v1.pdf
A. J. Krasznahorkay et al. Observation of Anomalous Internal Pair Creation in: A Possible Indication of a Light, Neutral Boson, Physical Review Letters (2016).

 

DOI: 10.1103/PhysRevLett.116.042501

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Teaching robots to feel pain to protect themselves

Teaching robots to feel pain to protect themselves | Amazing Science | Scoop.it

A pair of researchers with Leibniz University of Hannover has demonstrated the means by which robots might be programmed to experience something akin to pain in animals. As part of their demonstration at last week's IEEE International Conference on Robotics and Automation held in Stockholm, Johannes Kuehn and Sami Haddaddin showed how pain might be used in robots, by interacting with a BioTac fingertip sensor on the end of a Kuka robotic arm that had been programmed to react differently to differing amounts of "pain."

 

The researchers explained that the reason for giving robots pain sensors is the same as for existing biological adaptations—to ensure a reaction that will lessen the damage incurred by our bodies, and perhaps, even more importantly, to help us to remember to avoid similar situations in the future. In the case of the robots, the researchers have built an electric network behind the fingertip sensor meant to mimic nerve pathways below the skin in animals, allowing the robot to "feel" what has been programmed to describe various types, or degrees of pain.

 

In the demonstration, the researchers inflicted varying degrees of pain on the robot, explaining the reasoning behind the programmed reaction: When experiencing light pain or discomfort, for example, the robot recoiled slowly, removing itself from the problem. Moderate pain, on the other hand called for a rapid response, moving quickly away from the source, though it had the option to move back, albeit, tentatively, if need be. Severe pain, on the other hand, is often indicative of damage, thus the robot had been programmed to become passive to prevent further damage.

 

Such robots are likely to incite a host of questions, of course, if they become more common—if a robot acts the same way a human does when touching a hot plate, are we to believe it is truly experiencing pain? And if so, will lawmakers find the need to enact laws to prevent cruelty to robots, as is the case with animals? Only time will tell of course, but one thing that is evident in such demonstrations—as robotics technology advances, researchers are more often forced to make hard decisions, some of which may fall entirely outside the domain of engineers.

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Of monsters, moonshine and shadows

Of monsters, moonshine and shadows | Amazing Science | Scoop.it
Monsters, moonshine and shadows sound like the ingredients for an excellent fairy tale. They are also part of a fascinating mathematical story that brings together some of our favorite things – number theory, group theory, string theory and even quantum gravity – as well as some of our favorite mathematicians.
 
The monster in question comes from group theory – the mathematical study of symmetry. A group is a set of things (usually called elements) and a rule for how these elements interact so the resulting system is self contained and satisfies some simple rules. You can read all the details in The power of groups.
 
One of the original inspirations for group theory came from studying symmetry groups – the symmetries that can exists together in an object. For example the symmetries of a rectangle are reflection in the vertical axis, reflection in the horizontal axis and a half-turn around the centre. These symmetries of a rectangle, together with the identity symmetry (that does nothing), form the Klein 4-group – one of the smallest groups.
 
There are also infinite groups, such as the set of whole numbers which form a group under addition. But every group, finite or infinite, is made up of building blocks called simple groups in an analogous way to every number being uniquely expressible as a product of prime factors.
 
One of the greatest mathematical achievements of the last century was the classification of the finite simple groups, an enormous theorem that took over 30 years, 100 mathematicians and 10,000 pages to prove. This result gave a description of every type of finite simple group: they were either one of 18 well-understood infinite families (such as addition modulo a prime number, eg. addition modulo 7) or they were one of 26 other individual possibilities (called the sporadic groups). The largest of these 26 outsiders is the Monster group, which consists of a mind-boggling

808,017,424,794,512,875,886,459,904,961,710,757,005,754,368,000,000,000

symmetries.

 

It turns out that every group, whether it's the symmetries of a rectangle or the whole numbers under addition, can be represented using mathematical objects called matrices. These are extensions of one-dimensional linear functions, such as , to higher dimensions. Each element of the group corresponds to a matrix that acts in -dimensional space, and these matrices behave in the same way that the original group elements (that is if for elements , and in the group, then for the corresponding matrices , and in the group's representation).

 

A single group can even have several different representations in terms of matrices. The smallest irreducible representation of the Monster group is as a group of matrices representing rotations in 196,883-dimensional space. The next largest is in 21,296,876-dimensional space, the one after that is in 842,609,326-dimensional space, and there are 194 such representations of the Monster group (including the trivial 1-dimensional one where all elements of the group act like the identity) in all.

 

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Laser spectroscopy cuts explosive detection time from minutes to microseconds

Laser spectroscopy cuts explosive detection time from minutes to microseconds | Amazing Science | Scoop.it

Terahertz spectroscopy, which uses the band of electromagnetic radiation between microwaves and infrared light, is a promising security technology because it can extract the spectroscopic “fingerprints” of a wide range of materials, including chemicals used in explosives.

But traditional terahertz spectroscopy requires a radiation source that’s heavy and about the size of a large suitcase, and it takes 15 to 30 minutes to analyze a single sample, rendering it impractical for most applications.

In the latest issue of the journal Optica, researchers from MIT’s Research Laboratory of Electronics and their colleagues present a new terahertz spectroscopy system that uses a quantum cascade laser, a source of terahertz radiation that’s the size of a computer chip. The system can extract a material’s spectroscopic signature in just 100 microseconds.

The device is so efficient because it emits terahertz radiation in what’s known as a “frequency comb,” meaning a range of frequencies that are perfectly evenly spaced.Click here to edit the content

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Tools to annotate genes and genetic variants 

Tools to annotate genes and genetic variants  | Amazing Science | Scoop.it
 

Recently published in Genome Biology, Ginger Tsueng and colleagues discuss two high-performance web services for querying gene and variant annotation. Ginger explains more in this blog about the ideas behind the software, and how they advance the field.

 

Welcome to the big data landscape of gene and variant information! Vast swaths of gene and variant annotation information are spread across many different resources, making it challenging for researchers to integrate up-to-date information into their bioinformatics pipelines.

 

Researchers typically address this challenge with data warehousing or data federation. By downloading and storing data from different resources (data warehousing), researchers ensure fast access to data of interest to them; however, effort must be spent on writing papers and keeping the data up-to-date.

 

In contrast, by accessing the data directly from the resource when it is needed (data federation), researchers ensure that they obtain the most up-to-date information available from these resources, but may find their queries to be time consuming due to server and network limitations.

 

In a recently published paper in Genome Biology Jiwen Xin, et al. describe an alternative solution for obtaining up-to-date gene and variant annotation data from multiple resources: the annotation as a service. Like the hardware superstore in bridge example, MyGene.info and MyVariant.info are one-stop shops (i.e. centralized repositories) that serve up-to-date annotation data from key resources via cloud-based web-service endpoints. MyGene.info stores up-to-date data from NCBI Entrez, Ensembl, Uniprot, NetAffy, PharmGKB, UCSC, and CPDB.

 

Instead of dealing with data warehousing or data federation issues in addition to data format conversion from multiple data sources, researchers or bioinformaticians can utilize any of MyGene.info’s clients (Python, R) or browser-based API to access up-to-date gene annotation data in a single machine-readable format (json). For example, MyGene.info can easily be used to batch convert gene IDs or obtain pertinent gene ontology info—two tasks for which researchers commonly use and cite DAVID. Providing easy access to gene annotation information like gene IDs and gene ontology is so valuable that researchers continue to use DAVID for this purpose even though DAVID has not been updated for a long time!

 

“With over 50 different annotations types covering over 13 million genes for 15,000 species, MyGene.info has already accumulated over 160 million requests, and serves an average of 3.5 million requests per month!” Dr. Chunlei Wu revealed, the Associate Professor at the Scripps Research Institute in charge of developing these services.

 

Elaborating on the development of MyVariant.info, he added, “After confirming that researchers would find this resource valuable and seeing the volume of requests we get monthly, we wanted to find a similar solution for gene variant annotation data. That was the idea behind MyVariant.info.”

 

MyVariant.info currently incorporates up-to-date variant annotation data from fourteen valuable resources including: dbNSFP, dbSNP, ClinVar, EVS, CADD, MutDB, GWAS Catalog, COSMIC, DOCM, SNPedia, EMVClass, Scripps Wellderly, EXAC, and GRASP.


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Animated map showing the dramatic spread of agriculture over the last 300 years

Animated map showing the dramatic spread of agriculture over the last 300 years | Amazing Science | Scoop.it

The map, produced by Radicalcartography.net shows the amount of land given over to agriculture around the world over the three centuries leading up to the year 2000.

 

The map shows that in 1700, outside of Europe and Asia there was a very small proportion of land being farmed. The 18th century saw an increase in arable land for use and the beginnings of a vast improvement in agricultural yields. New farming methods, such as four-field crop rotation, the increased use of fertilizer and increasing mechanization, opened up additional swaths of land for agriculture.

 

Technology developed in the First and Second Industrial Revolutions saw farming rapidly expand into previously untapped areas, such as the American Great Plains in the late 19th century and Argentina in the early 20th century.

 

Expansion and intensification of existing farming continued into recent decades, with Brazil and central India becoming more intensely farmed since the late 20th century.

 

Historian and cartographer Bill Rankin argues that existing arable land has become "more and more agricultural". It is estimated that the productivity of wheat in England went up from about 19 bushels per acre in 1720 to around 30 bushels by 1840.

 

In recent years intensification has increased and land expansion has slowed in the developed world. This is largely down to the increased use of fertilizer, which has improved production yields.


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Combined climate, orbit models show that Kepler-62f could sustain life

Combined climate, orbit models show that Kepler-62f could sustain life | Amazing Science | Scoop.it
A distant planet known as Kepler-62f could be habitable, a team of astronomers reports.

 

The planet, which is about 1,200 light-years from Earth in the direction of the constellation Lyra, is approximately 40 percent larger than Earth. At that size, Kepler-62f is within the range of planets that are likely to be rocky and possibly could have oceans, said Aomawa Shields, the study's lead author and a National Science Foundation astronomy and astrophysics postdoctoral fellow in UCLA's department of physics and astronomy.

 

NASA's Kepler mission discovered the planetary system that includes Kepler-62f in 2013, and it identified Kepler-62f as the outermost of five planets orbiting a star that is smaller and cooler than the sun. But the mission didn't produce information about Kepler-62f's composition or atmosphere or the shape of its orbit.

Shields collaborated on the study with astronomers Rory Barnes,

 

Eric Agol, Benjamin Charnay, Cecilia Bitz and Victoria Meadows, all of the University of Washington, where Shields earned her doctorate. To determine whether the planet could sustain life, the team came up with possible scenarios about what its atmosphere might be like and what the shape of its orbit might be.

 

"We found there are multiple atmospheric compositions that allow it to be warm enough to have surface liquid water," said Shields, a University of California President's Postdoctoral Program Fellow. "This makes it a strong candidate for a habitable planet."

 

On Earth, carbon dioxide makes up 0.04 percent of the atmosphere. Because Kepler-62f is much farther away from its star than Earth is from the sun, it would need to have dramatically more carbon dioxide to be warm enough to maintain liquid water on its surface, and to keep from freezing.

 

Shields said that for the planet to be consistently habitable throughout its entire year, it would require an atmosphere that is three to five times thicker than Earth's and composed entirely of carbon dioxide. (This would be analogous to replacing every molecule in Earth's atmosphere with carbon dioxide, which means that the planet would have 2,500 times more carbon dioxide in its atmosphere.) Having such a high concentration of carbon dioxide would be possible for the planet because, given how far it is from its star, the gas could build up in the planet's atmosphere as temperatures get colder to keep the planet warm.

 

"But if it doesn't have a mechanism to generate lots of carbon dioxide in its atmosphere to keep temperatures warm, and all it had was an Earth-like amount of carbon dioxide, certain orbital configurations could allow Kepler-62f's surface temperatures to temporarily get above freezing during a portion of its year," she said. "And this might help melt ice sheets formed at other times in the planet's orbit."

 

The research is published online in the journal Astrobiology

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Optics breakthrough to revamp night vision

Optics breakthrough to revamp night vision | Amazing Science | Scoop.it

A breakthrough by an Australian collaboration of researchers could make infra-red technology easy-to-use and cheap, potentially saving millions of dollars in defense and other areas using sensing devices, and boosting application.

 

When light falls on a very thin, uniform layer almost all of it is reflected (right-hand arrows). By etching thin grooves in the film, the light is directed sideways and almost all of it is absorbed (left-hand arrows) even though the amount of material is very small. Insets show electron micrographs of the structuring. The absorbing layer is only 0.041 μm thick.

 

Infra-red devices are used for improved vision through fog and for night vision and for observations not possible with visible light; high-quality detectors cost approximately $100,000 (including the device at the University of Sydney) some require cooling to -200°C.

Now, research spearheaded by researchers at the University of Sydney has demonstrated a dramatic increase in the absorption efficiency of light in a layer of semiconductor that is only a few hundred atoms thick - to almost 99 percent light absorption from the current inefficient 7.7 percent. The findings will be published overnight in the high-impact journal Optica.

 

Co-author from the University of Sydney's School of Physics, Professor Martijn de Sterke, said the team discovered perfect thin film light absorbers could be created simply by etching grooves into them. "Conventional absorbers add bulk and cost to the infrared detector as well as the need for continuous power to keep the temperature down. The ultrathin absorbers can reduce these drawbacks," Professor de Sterke said. "By etching thin grooves in the film, the light is directed sideways and almost all of it is absorbed, despite the small amount of material - the absorbing layer is less than 1/2000th the thickness of a human hair," he said.

 

Co-lead author Dr Björn Sturmberg, who carried out the research as a PhD student at the University of Sydney with the support of the Australian Renewable Energy Agency, said the findings did not rely upon a particular material but could be applied to many naturally occurring weak absorbers. "There are many applications that could greatly benefit from perfectly absorbing ultra-thin films, ranging from defence and autonomous farming robots to medical tools and consumer electronics," Dr Sturmberg said.

 

The Director of Australia's National Computational Infrastructure (NCI) and co-author, of the paper, Professor Lindsay Botten, said the structures were much simpler to design and fabricate than using existing thin film light absorbers, which required either complex nanostructures, meta-materials and exotic materials or difficult-to-create combinations of metals and non-metals.

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The Most Amazing Galaxies In The Universe

The Most Amazing Galaxies In The Universe | Amazing Science | Scoop.it

There could be as many as 100 to 200 billion galaxies in the observable universe. One of the most comprehensive listings comes from Galaxy Zoo, a crowdsourced astronomy project launched in 2007, which has so far classified over one million galaxy images from Sloan Digital Sky Survey, Hubble Space Telescope, and the Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey. From such a vast database, it is hard to pick favorites - they are all dazzling clusters of stars and celestial objects. Nevertheless, here is a list of some of the most amazing galaxies categorized according to their general type (Milky Way excluded).

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Scientists Find a Better Way to Make Structures to Create DNA Based Tech

Scientists Find a Better Way to Make Structures to Create DNA Based Tech | Amazing Science | Scoop.it
Researchers have designed a new algorithm that automates the manipulation and sculpting of DNA into different shapes—a process known as DNA origami.

 

A team of researchers from MIT, Arizona State University, and Baylor University have devised a new computer algorithm that does all the hard work for you. The results of their research have been published in the journal Science.

 

“The paper turns the problem around from one in which an expert designs the DNA needed to synthesize the object, to one in which the object itself is the starting point, with the DNA sequences that are needed automatically defined by the algorithm,” says Mark Bathe, associate professor of biological engineering at MIT, and lead researcher for the study.

 

The new algorithm, which the team has called DAEDALUS, automates the entire business of sculpting DNA shapes; essentially, you begin with the desired shape (which must have a closed surface) and feed it into the algorithm, which then maps out the order of bases (adenine, guanine, cytosine and thymine) needed to produce the DNA “scaffold.”

 

DAEDALUS means “open source” DNA origami, enabling anyone with the inclination and access to the algorithm to design and create their own DNA-based, nanoscale objects. What Henry Ford’s assembly line concept did for manufacturing, DAEDALUS promises to do for nanoscale structures.

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The Real Secret of Youth Is Complexity

The Real Secret of Youth Is Complexity | Amazing Science | Scoop.it
Youthful health and vigor depend, in many ways, on complexity. Bones get strength from elaborate scaffolds of connective tissue. Mental acuity arises from interconnected webs of neurons. Even seemingly simple bodily functions like heartbeat rely on interacting networks of metabolic controls, signaling pathways, genetic switches, and circadian rhythms. As our bodies age, these anatomic structures and physiologic processes lose complexity, making them less resilient and ultimately leading to frailty and disease.
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Physicists Make Black Hole in Lab That May Finally Prove Hawking Radiation Exists

Physicists Make Black Hole in Lab That May Finally Prove Hawking Radiation Exists | Amazing Science | Scoop.it

Some 42 years ago, renowned theoretical physicist Stephen Hawking proposed that not everything that comes in contact with a black hole succumbs to its unfathomable nothingness. Tiny particles of light (photons) are sometimes ejected back out, robbing the black hole of an infinitesimal amount of energy, and this gradual loss of mass over time means every black hole eventually evaporates out of existence.

 

Known as Hawking radiation, these escaping particles help us make sense of one of the greatest enigmas in the known Universe, but after more than four decades, no one’s been able to actually prove they exist, and Hawking’s proposal remained firmly in hypothesis territory.

 

But all that could be about to change, with two independent groups of researchers reporting that they’ve found evidence to back up Hawking’s claims, and it could see one of the greatest living physicists finally win a Nobel Prize.

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Mixed-up metals make for stronger, tougher, stretchier alloys

Mixed-up metals make for stronger, tougher, stretchier alloys | Amazing Science | Scoop.it
Materials scientists are creating next-generation mixtures with remarkable properties.

 

At first glance, the machine seems to be building a miniature cityscape. A ring of nozzles fires four jets of powdered metal into a downward-pointed laser beam, which fuses the colliding grains in a bright orange glow. The mixed grains then solidify on the growing tip of a small pillar of metal alloy. Once the pillar is 1–2 centimeters high, the platform that holds it shifts to the side, and the machine starts to build another one right next door. The result looks like a forest of toy skyscrapers.

 

In reality, these towers, generated at the Ames Laboratory in Iowa, reflect a major shift in how researchers think about alloys. The standard recipe — used for technologies ranging from ancient swords and arrowheads to modern jet-engine turbines — is to take a useful metal and mix in a pinch of this or a touch of that to improve its properties. One classic example is the addition of carbon to iron to make steel.

 

But the machine at Ames is making experimental samples of 'high-entropy' alloys, which consist of four, five or more elements mixed together in roughly equal ratios. This deceptively simple recipe can yield alloys that are lighter and stronger than their conventional counterparts, while being much more resistant to corrosion, radiation or severe wear. Eventually, researchers hope, this approach could even produce alloys that have magnetic or electrical properties never seen before, leading to whole new generations of technology.

 

“We have almost explored everything for traditional alloys,” says Yong Zhang, a materials scientist with the State Key Laboratory for Advanced Metals and Materials at the University of Science and Technology Beijing. “For high-entropy alloys, the science is very new,” he says — so new that no such alloy has yet made the leap from lab to market. But some researchers are working to make that happen, eyeing potential applications that range from high-temperature furnace linings to ultralightweight aerospace materials. And the field has attracted funding from research agencies in China, Europe, the United States and elsewhere.

 

“We're not talking about a narrow class of materials, but an extremely broad philosophy on how to combine elements,” says Daniel Miracle, a materials scientist at the Air Force Research Laboratory at the Wright-Patterson Air Force Base in Ohio. “The opportunity to find something new and exciting is very high.” Last year, he and his colleagues estimated1 that almost 313,560 different alloys can be made by combining exactly equal proportions of 3, 4, 5 or 6 metallic elements from a set of just 26. More possibilities can come from varying the proportions or expanding the choice of elements.

 

But not every combination is a winner, says Easo George, a materials engineer at Ruhr University Bochum in Germany. Scientists are still learning what works and what doesn't. Still, he says, “the space available for exploration is really huge, and we have only looked at a small portion of the Universe”.

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Fast, stretchy circuits could yield new wave of wearable electronics

Fast, stretchy circuits could yield new wave of wearable electronics | Amazing Science | Scoop.it

The consumer marketplace is flooded with a lively assortment of smart wearable electronics that do everything from monitor vital signs, fitness or sun exposure to play music, charge other electronics or even purify the air around you - all wirelessly.

 

Now, a team of University of Wisconsin-Madison engineers has created the world's fastest stretchable, wearable integrated circuits, an advance that could drive the Internet of Things and a much more connected, high-speed wireless world.

 

Led by Zhenqiang "Jack" Ma, the Lynn H. Matthias Professor in Engineering and Vilas Distinguished Achievement Professor in electrical and computer engineering at UW-Madison, the researchers published details of these powerful, highly efficient integrated circuits today, May 27, 2016, in the journal Advanced Functional Materials.

 

The advance is a platform for manufacturers seeking to expand the capabilities and applications of wearable electronics—including those with biomedical applications—particularly as they strive to develop devices that take advantage of a new generation of wireless broadband technologies referred to as 5G.

 

With wavelength sizes between a millimeter and a meter, microwave radio frequencies are electromagnetic waves that use frequencies in the .3 gigahertz to 300 gigahertz range. That falls directly in the 5G range.

 

In mobile communications, the wide microwave radio frequencies of 5G networks will accommodate a growing number of cellphone users and notable increases in data speeds and coverage areas.

 

In an intensive care unit, epidermal electronic systems (electronics that adhere to the skin like temporary tattoos) could allow health care staff to monitor patients remotely and wirelessly, increasing patient comfort by decreasing the customary tangle of cables and wires.

 

What makes the new, stretchable integrated circuits so powerful is their unique structure, inspired by twisted-pair telephone cables. They contain, essentially, two ultra-tiny intertwining power transmission lines in repeating S-curves.

 

This serpentine shape—formed in two layers with segmented metal blocks, like a 3-D puzzle—gives the transmission lines the ability to stretch without affecting their performance. It also helps shield the lines from outside interference and, at the same time, confine the electromagnetic waves flowing through them, almost completely eliminating current loss. Currently, the researchers' stretchable integrated circuits can operate at radio frequency levels up to 40 gigahertz.

 

And, unlike other stretchable transmission lines, whose widths can approach 640 micrometers (or .64 millimeters), the researchers' new stretchable integrated circuits are just 25 micrometers (or .025 millimeters) thick. That's tiny enough to be highly effective in epidermal electronic systems, among many other applications.

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New telescopes will search for signs of life on distant planets

New telescopes will search for signs of life on distant planets | Amazing Science | Scoop.it
Researchers are coming up with creative ways to pick up biosignatures in far-away planetary atmospheres.

 

Our galaxy is teeming with planets. Over the last 25 years, astronomers have cataloged about 2,000 worlds in 1,300 systems scattered around our stellar neighborhood. While most of these exoplanets look nothing like Earth (and in some cases, like nothing that orbits our sun), the bonanza of alien worlds implies a tantalizing possibility: There is a lot of real estate out there suitable for life.

 

We haven’t explored every corner of our solar system. Life might be lurking beneath the surface of some icy satellites or in the soil of Mars. For such locales, we could conceivably visit and look for anything wriggling or replicating. But we can’t travel (yet) to worlds orbiting remote suns dozens of light-years away. An advanced alien civilization might transmit detectable radio signals, but primitive life would not be able to announce its presence to the cosmos.

 

People have contemplated the possibility of extraterrestrial life since medieval times. We’re still looking for answers today. What would aliens look like? Where should we look to find them? Why are we so obsessed? Science News writers explore these questions and more in this special report.

 

On Earth, life alters the atmosphere. If plants and critters weren’t around to keep churning out oxygen and methane, those gases would quickly vanish. Water, carbon dioxide, methane, oxygen and ozone are examples of “biosignatures,” key markers of a planet crawling with life as we know it. Setting aside questions about how recognizable alien life might be, detecting biosignatures in the atmosphere of an exoplanet would give astronomers the first strong clue that we are not alone.

 

Biosignatures aren’t proof of thriving ecosystems. Ultraviolet light from a planet’s sun can zap water molecules and create a stockpile of oxygen; seawater filtering through rocks can produce methane. “We’ll never be able to say 100 percent that a planet has life,” says Sarah Rugheimer, an astrophysicist at the University of St. Andrews in Scotland. But astronomers hope that, given enough information about an exoplanet and the star it orbits, they can build a case for a world where sunlight and geology aren’t enough to explain its chemistry — one where life is a viable possibility. Finding a planet similar to Earth is probably still decades away, but thanks to a couple of upcoming telescopes, astronomers might be on the verge of spying on habitable worlds around nearby stars.

 

NASA’s Transiting Exoplanet Survey Satellite, or TESS, will launch in 2017 on a quest to detect many of the exoplanets that orbit the stars closest to us. One year later, the James Webb Space Telescope will launch and peek inside some of these newfound atmospheres. With their powers combined, TESS and James Webb could identify nearby planets that are good candidates for life. These worlds will probably be quite different from Earth — they’ll be a bit larger and orbit faint, red suns — but some researchers hope that a few will offer hints of alien biology.

 

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Two Worlds, One Sun: Blue Sunsets on Mars

Two Worlds, One Sun: Blue Sunsets on Mars | Amazing Science | Scoop.it
While Earth can have lovely red sunsets, Mars can have a sunset that is truly blue.

 

Earth has a relatively thick atmosphere, so most of the atmospheric scattering occurs when light strikes a molecule of air, known as Rayleigh scattering. Rayleigh scattering occurs when the object a photon scatters off (the air molecule) is much smaller than the wavelength of the photon. The closer the wavelength is to the size of the molecule, the more likely it is to scatter. This means that red wavelengths (which are the longer wavelengths of visible light) don’t scatter with air molecules much, while blue wavelengths (which are shorter) tend to scatter a lot. In fact blue light is almost 10 times more likely to scatter against air molecules than red light. This is why the sky appears blue, since so much of the blue light is scattered.

 

When the Sun is low in the sky, it’s light has to travel a long path through the atmosphere to reach you. As the light travels through the atmosphere some of the photons are scattered off the air molecules. When the photons scatter off air molecules, they scatter randomly in all directions, so usually when a photon scatters, it scatters away from your line of sight. Since blue photons scatter much more often than red ones, much of the blue light is scattered away. This leaves red photons to reach your eye. Hence the Sun looks red when low in the sky. When the Sun is overhead, the path it takes to reach you is much shorter, so only a bit of the blue light is scattered. So the Sun looks yellow.

 

Mars has a much thinner atmosphere, so the amount of Rayleigh scattering is much less. But Mars also has a dry, dusty surface, and a weaker surface gravity, so the atmosphere of Mars is often filled with fine dust particles. These particles are more comparable in size to the wavelengths of visible light, so most of the light is scattered by Mie scattering. One of the main differences between Rayleigh and Mie scattering is that Rayleigh scattering tends to occur in all directions, but Mie scattering varies with scattering angle. What this means is that longer wavelengths (reds) tend to scatter more uniformly, while shorter wavelengths (blues) tend to scatter at slight angles. This means that blue light tends to be deflected less than red light. This means Mars can have a dusty red daytime sky, and a blue sunset.

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