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Creating improved inkjet-printable materials for electronics and photonics

Creating improved inkjet-printable materials for electronics and photonics | Amazing Science | Scoop.it

Transition-metal dichalcogenides like molybdenum disulphide have attracted great interest as two-dimensional materials beyond graphene due to their unique electronic and optical properties. Solution-phase processes can be a viable method for producing printable single-layer chalcogenides. Molybdenum disulphide can be exfoliated into monolayer flakes using organolithium reduction chemistry; unfortunately, the method is hampered by low yield, submicron flake size and long lithiation time.


National University of Singapore (NUS) scientists have developed a new method for creating a chemical solution of molybdenum disulfide for use in printable optoelectronic devices such as thin film solar cells, flexible logic circuits, photodetectors, and sensors.


Molybdenum disulfide, combined with gold atoms, is being studied for development of ultrafast, ultrathin logic devices, as noted previously on KurzweilAI.


The process:

  1. Chemically exfoliate (peel off) molybdenum disulfide crystals into high-quality single-layer flakes (the new method achieves higher yield and larger flake size than current methods).
  2. Convert the flakes into an inkjet-printable solution (the good dispersion and high viscosity of the flakes make them highly suitable for inkjet printing).
  3. Print wafer-size films. Current processes of producing printable single-layer chalcogenides (such as molybdenum disulfide) take a long time and the yield is poor. The flakes produced are of submicron sizes, which make it challenging to isolate a single sheet for making electronic devices.


REFERENCES:

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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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Michel Jammes's curator insight, December 30, 2013 1:02 AM

MOOC , not a buzz word , a reality...

Margarida Sá Costa's curator insight, January 31, 6:55 AM

Lectures are in Playlists and are alphabetically sorted with thumbnail pictures. No fee, no registration required - learn at your own pace. Certificates can be arranged with presenting universities.

Casper Pieters's curator insight, March 9, 4:21 PM

Great resources for online learning just about everything.  All you need is will power and self- discipline.

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Gene Therapy Boosts Cochlear Implants and Could Restore Hearing to the Deaf

Gene Therapy Boosts Cochlear Implants and Could Restore Hearing to the Deaf | Amazing Science | Scoop.it
Today researchers announced that they've been able to restore tonal hearing in guinea pigs with the new method of gene delivery.


The team implanted “bionic ears” in deaf guinea pigs, whose auditory systems are very similar to humans’. With the device, then, they delivered DNA that coded for a protein called brain-derived neruotrophic factor (BDNF), which encourages nerves to grow. The DNA was taken up by cells in the cochlea and, after two weeks, the nerves had grown significantly toward the electrodes. When the guinea pigs’ hearing was tested they found that animals that were once completely deaf had their hearing restored to almost normal levels.


It’s unclear, however, whether the treatment will work long-term: neuron production in the guinea pigs dropped off six weeks after the gene therapy. Researchers are also unsure whether tones heard after this treatment accurately reflect how they sound with normal hearing.


The technique is very close to being ready for human trials, where some of these questions should be answered. If it proves successful in clinical trials, the technique of combining gene therapy with device could also be used for other implants like retinal prosthesis and deep brain stimulation.

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Gecko-like Adhesives Now Useful for Real World Surfaces

Gecko-like Adhesives Now Useful for Real World Surfaces | Amazing Science | Scoop.it

The ability to stick objects to a wide range of surfaces such as drywall, wood, metal and glass with a single adhesive has been the elusive goal of many research teams across the world, but now a team of University of Massachusetts Amherst inventors describe a new, more versatile version of their invention, Geckskin, that can adhere strongly to a wider range of surfaces, yet releases easily, like a gecko’s feet.


“Imagine sticking your tablet on a wall to watch your favorite movie and then moving it to a new location when you want, without the need for pesky holes in your painted wall,” says polymer science and engineering professor Al Crosby. Geckskin is a ‘gecko-like,’ reusable adhesive device that they had previously demonstrated can hold heavy loads on smooth surfaces such as glass.


Crosby and polymer science researcher Dan King, with other UMass Amherst researchers including biology professor Duncan Irschick, report in the current issue of Advanced Materials how they have expanded their design theory to allow Geckskin to adhere powerfully to a wider variety of surfaces found in most homes such as drywall, and wood.


Unlike other gecko-like materials, the UMass Amherst invention does not rely on mimicking the tiny, nanoscopic hairs found on gecko feet, but rather builds on “draping adhesion,” which derives from the gecko’s integrated anatomical skin-tendon-bone system. As King explains, “The key to making a strong adhesive connection is to conform to a surface while still maximizing stiffness.”


In Geckskin, the researchers created this ability by combining soft elastomers and ultra-stiff fabrics such as glass or carbon fiber fabrics. By “tuning” the relative stiffness of these materials, they can optimize Geckskin for a range of applications, the inventors say.


To substantiate their claims of Geckskin’s properties, the UMass Amherst team compared three versions to the abilities of a living Tokay gecko on several surfaces, as described in their journal article this month. As predicted by their theory, one Geckskin version matches and even exceeds the gecko’s performance on all tested surfaces.


Irschick points out, “The gecko’s ability to stick to a variety of surfaces is critical for its survival, but it’s equally important to be able to release and re-stick whenever it wants. Geckskin displays the same ability on different commonly used surfaces, opening up great possibilities for new technologies in the home, office or outdoors.”

Crosby notes, “It’s been a lot of fun thinking about all of the different things you ever would want to hang somewhere, and then doing it. Geckskin changes the way you think.” 

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Unravelling How Planaria Regenerate: Cut into 279 tiny pieces, each one regenerates to a full worm

Unravelling How Planaria Regenerate: Cut into 279 tiny pieces, each one regenerates to a full worm | Amazing Science | Scoop.it
Researchers have begun teasing apart the genes behind regeneration.


Planarian flatworms are one of nature's little wonders. Although their 'cross-eyed' appearance is endearing, their real claim to fame comes from their regenerative ability. Split a planarian down the middle and you'll soon have two cross-eyed critters staring back at you; cut one up and each piece will regenerate an entire flatworm. How do they pull of such an incredible feat? In 2011, researchers discovered that planarian regeneration depends on the activity of stem cells ('neoblasts') distributed throughout the flatworm's body, but important questions about the process have remained unanswered. Are certain stem cells responsible for each organ? What activates the stem cells when regeneration is needed? An enterprising team of scientists at the Stowers Institute for Medical Research has brought us closer to answering these questions by developing a new technique to study planarian regeneration and using it to discover some of they genes involved.

Regeneration isn't a uniquely planarian trait; starfish are well-known for growing back lost body parts, and even humans can regenerate to some extent (think of a wound healing). Planarians certainly excel at it, though; a flatworm can recover from being cut up into a staggering 279 tiny pieces, each of which regenerates into a new worm! Here's a fun conundrum for those inclined to such things: which worm, if any, can claim to be the 'original worm'? What if it were only two pieces instead of over 200? Would it make a difference if the two pieces were different sizes?


Using this technique, which they termed 'chemical amputation', the team induced lesions in planaria and investigated which genes were activated over the course of the regeneration process. The pharynx lacks neoblasts, but cells near the wound quickly start dividing and regenerate the amputated organ. To identify genes which were interesting, the team combined two screening approaches. First, a microarray picked out genes which were active during regeneration, providing a list of 356 candidates. Next, the team used RNAi to block the activity of each gene in amputated flatworms and checked whether the pharynx still regenerated. This narrowed the list down to twenty genes, which the team divided into different sets. Some genes affected stem cells in general, other affected feeding behaviour, and a handful directly affected the development of the pharynx. Of these, the transcription factor FoxA seemed to play the greatest role in regenerating the pharynx.

The team next looked at how regeneration went wrong in planaria with FoxA knocked down. They found that stem cells still migrated to the wound site and multiplied there, but the resulting outgrowth failed to become a pharynx. They also tried amputating the tails or heads of FoxA knock-downs, which then successfully regenerated. "Targeting FoxA completely blocked pharynx regeneration but had no effect on the regeneration of other organs," said Adler in a press release. “Currently, we think that FoxA triggers a cascade of gene expression that drives stem cells to produce all of the different cells of the pharynx, including muscle, neurons, and epithelial cells.” FoxA is known to play a role in specifying the pharynx in the sea anemone and in the nematode Caenorhabditis elegans, as well regulating the development of the intestine in vertebrates, so it makes sense that it's a central player in pharynx regeneration in planaria. More importantly, its identification can serve as a wedge to pry apart the details of regeneration; coupled with the other genes picked up in this study, it offers an exciting opportunity to expand our understanding of this important process.


References:

Adler C, et al. Selective amputation of the pharynx identifies a FoxA-dependent regeneration program in planariaeLife 3:e02238. (2014) doi:10.7554/eLife.02238


Rossant J. Genes for RegenerationeLife 3:e02517. (2014) doi:10.7554/eLife.02517

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Volcanoes That Act as Air-Conditioning for a Warming World

Volcanoes That Act as Air-Conditioning for a Warming World | Amazing Science | Scoop.it

Many small eruptions over the past decade or so have helped restrain climate change.


On Valentine's Day, Indonesia's Mount Kelud blew its top and coated villages up to 500 kilometers away with ash. At the same time, the eruption injected a small but consequential amount of sulfur dioxide 28 kilometers up into the stratosphere. Tiny droplets of sulfuric acid then reflected away incoming sunlight, helping to cool the planet. Such “small” eruptions—along with others at places like Manam, Soufrière Hills, Jebel at Tair and Eyjafjallajökull, to name a few of the 17 between 2000 and 2012—have helped slow the pace of global warming, according to work published in Nature Geoscience.


“The uptick in early 21st-century volcanism clearly was a contributing factor to the hiatus,” says atmospheric scientist Benjamin Santer of Lawrence Livermore National Laboratory, lead author of the report. The volcanoes did not act alone. There was also an unusually quiescent sun, air pollution from China's coal-fired power plants and the mysterious workings of the ocean. Santer adds, “The net impact was to offset part of the human-caused greenhouse gas warming.”


In the meantime, global warming continues to gather strength, hidden behind volcanoes that may shutter their tops at any moment. Based on supersized eruptions such as Mount Pinatubo in the Philippines in 1991, reflective aerosols would then fall to Earth within a few years at most, leaving the planet exposed to the full heat-trapping effects of greenhouse gases from human activities.


If the volcanoes do not do their part, a last resort may be required—bring our own aerosols. Advocates of one form of geoengineering want to step in, injecting sulfate aerosols in the stratosphere to augment or replace eruptions. Such deliberate tinkering with planetary-scale systems has been proposed as a fallback plan if climate change were to turn catastrophic, though at the cost of the stratospheric layer that helps to shield life from ultraviolet light. Sulfuric acid high in the sky has the unfortunate side effect of eliminating ozone. But given the inertia in reducing greenhouse gas pollution, the debate around geoengineering will undoubtedly linger longer than the aftermath of these small volcanic eruptions.

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NATURE: How to make graphene in a kitchen blender

NATURE: How to make graphene in a kitchen blender | Amazing Science | Scoop.it

In Nature Materials, a team led by Coleman (and funded by the UK-based firm Thomas Swan) describe how they took a high-power (400-watt) kitchen blender and added half a litre of water, 10–25 millilitres of detergent and 20–50 grams of graphite powder (found in pencil leads). They turned the machine on for 10–30 minutes. The result, the team reports: a large number of micrometre-sized flakes of graphene, suspended in the water.


Coleman adds, hastily, that the recipe involves a delicate balance of surfactant and graphite, which he has not yet disclosed (this barrier dissuaded me from trying it out; he is preparing a detailed kitchen recipe for later publication). And in his laboratory, centrifuges, electron microscopes and spectrometers were also used to separate out the graphene and test the outcome. In fact, the kitchen-blender recipe was added late in the study as a bit of a gimmick — the main work was done first with an industrial blender (pictured).


Still, he says, the example shows just how simple his new method is for making graphene in industrial quantities. Thomas Swan has scaled the (patented) process up into a pilot plant and, says commercial director Andy Goodwin, hopes to be making a kilogram of graphene a day by the end of this year, sold as a dried powder and as a liquid dispersion from which it may be sprayed onto other materials.


“It is a significant step forward towards cheap and scalable mass production,” says Andrea Ferrari, an expert on graphene at the University of Cambridge, UK. “The material is of a quality close to the best in the literature, but with production rates apparently hundreds of times higher.”


The quality of the flakes is not as high as that of the ones the winners of the 2010 Nobel Prize in Chemistry, Andre Geim and Kostya Novoselov from Manchester University, famously isolated using Scotch Tape to peel off single sheets from graphite. Nor are they as large as the metre-scale graphene sheets that firms today grow atom by atom from a vapour. But outside of high-end electronics applications, smaller flakes suffice — the real question is how to make lots of them.


Kitchen blenders aren’t the only way to produce reasonably high-quality flakes of graphene. Ferrari still thinks that using ultrasound to rip graphite apart could give better materials in some cases. And Xinliang Feng, from the Max Planck Institute for Polymer Research in Mainz, Germany, says that his recent publication, in the Journal of the American Chemical Society, reports a way to produce higher-quality, fewer-layer graphene at higher rates by electrochemical means. Coleman points out that Thomas Swan have taken the technique far beyond what is reported in the paper.


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Study confirms monkeys can do math

Study confirms monkeys can do math | Amazing Science | Scoop.it

Scientists have long suspected that monkeys are capable of mental arithmetics and a new study is helping them prove it. A research team led by neurobiologist Margaret Livingstone trained three rhesus macaques to identify symbols representing the numbers zero to 25. They then taught the test subjects how to perform addition. To eliminate the possibility of rote learning, the team had the monkeys learn an entirely different set of symbols representing the numbers zero to 25. The monkeys were able to reapply their previous knowledge to the new set and continue performing basic mathematics.


The image above shows one of the monkeys preparing to choose the four and five combination on the panel. It has learned that the combined value is greater than eight and will therefore yield a larger number of liquid drops. According to the study, all three monkeys were on average capable of choosing the correct answer "well above" 50 percent of the time. This rules out the possibility of chance. What's also interesting is how the monkeys were routinely undervaluing the smaller number in a given equation. This challenges the idea that mammalian brains perceive numbers logarithmically and may help researchers better understand how human beings process numbers.



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Eli Levine's curator insight, April 22, 8:33 AM

And we think we're the only intelligent ones in the universe.

 

Forget about finding sentient life on other planets, there's plenty of it down here on Earth.

 

Arguably, these animals are somewhat smarter than at least the people who are running the show in our current incarnation of society.  These animals at least don't destroy the world in which they're living in for the sake of abstract concepts, ideologies, beliefs, preferences or any other thing that is not really needed for our sake and well being, as organisms first.

 

Diseased brains, that's who we've got running our show.

 

And it is all thanks to their brains and sense organs that they're unable to connect with life, the universe and everything for their own sakes in the context of life, the universe and everything, let alone, for all of ours'.

 

Take them out in straight jackets, from corporate executives, to ideological leaders, to shareholders, to all politicians who won't or don't adapt according to natural law and societal laws.  No harm to the insane and pathetic.  If they resist, use tasers and tranquilizer guns to stun them.  These people are dangerous to themselves and dangerous to others, no matter what position they may be holding at present.

 

All our leadership cadre must change, in practice and in content.

 

Or else, they're going to die too, along with all the rest of us.

 

Silly brains.

 

Think about it.

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Chickens living just a few hundred years ago may have looked far different from the chickens of today

Chickens living just a few hundred years ago may have looked far different from the chickens of today | Amazing Science | Scoop.it

Ancient DNA adds a twist to the story of how barnyard chickens came to be, finds a study to be published April 21 in the journal Proceedings of the National Academy of Sciences.


Analyzing DNA from the bones of chickens that lived 200-2300 years ago in Europe, researchers report that just a few hundred years ago domestic chickens may have looked far different from the chickens we know today.


The results suggest that some of the traits we associate with modern domestic chickens — such as their yellowish skin — only became widespread in the last 500 years, much more recently than previously thought.


The study is part of a larger field of research that aims to understand when, where and how humans turned wild plants and animals into the crops, pets and livestock we know today.


Generally, any mutations that are widespread in domestic plants and animals but absent from their wild relatives are assumed to have played a key role in the process, spreading as people and their livestock moved across the globe. But a growing number of ancient DNA studies tell a different tale.


Chickens are descended from a wild bird called the Red Junglefowl that humans started raising roughly 4,000-5,000 years ago in South Asia. To pinpoint the genetic changes that transformed this shy, wild bird into the chickens we know today, researchers analyzed DNA from the skeletal remains of 81 chickens retrieved from a dozen archeological sites across Europe dating from 200 to 2,300 years old.


The researchers focused on two genes known to differ between domestic chickens and their wild counterparts: a gene associated with yellow skin color, called BCDO2, and a gene involved in thyroid hormone production, called TSHR.


Though the exact function of TSHR is unknown, it may be linked to the domestic chicken’s ability to lay eggs year-round – a trait that Red Junglefowl and other wild birds don’t have.


When the team compared the ancient sequences to the DNA of modern chickens, only one of the ancient chickens had the yellow skin so common in chickens today. Similarly, less than half of the ancient chickens had the version of the TSHR gene found worldwide in modern chickens.


The results suggest that these traits only became widespread within the last 500 years — thousands of years after the first barnyard chickens came to be. “Just because a plant or animal trait is common today doesn’t mean that it was bred into them from the beginning,” Larson said.

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Brain 'Stones' Found in Man with Celiac Disease

Brain 'Stones' Found in Man with Celiac Disease | Amazing Science | Scoop.it
A young man in Brazil who suffered from throbbing headaches and vision problems for 10 years turned out to have stone-like build-ups of calcium in his brain.


The stones were likely a rare complication of the man's celiac disease, a digestive condition that the man didn't know he had, according to a new report of his case.


Because of his recurring headaches and vision problems, the man had been treated for migraines, but he hadn't improved. When doctors did a CT scan, they found patches of calcification in the back of the man's brain, in the areas that handle vision.

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Molecular scale MRI: System designed to peer into the atomic structure of individual molecules

Molecular scale MRI: System designed to peer into the atomic structure of individual molecules | Amazing Science | Scoop.it

A team of scientists, led by Professor of Physics and of Applied Physics Amir Yacoby, has developed a magnetic resonance imaging (MRI) system that can produce nanoscale images, and may one day allow researchers to peer into the atomic structure of individual molecules. Their work is described in a March 23 paper in Nature Nanotechnology.


“What we’ve demonstrated in this new paper is the ability to get very high spatial resolution, and a fully operational MRI technology,” Yacoby said. “This work is directed toward obtaining detailed information on molecular structure. If we can image a single molecule and identify that there is a hydrogen atom here and a carbon there … we can obtain information about the structure of many molecules that cannot be imaged by any other technique today.”


Though not yet precise enough to capture atomic-scale images of a single molecule, the system already has been used to capture images of single electron spins. As the system is refined, Yacoby said he expects it eventually will be precise enough to peer into the structure of molecules.

While the system designed by Yacoby and colleagues operates in much the same way conventional MRIs do, the similarities end there.


“What we’ve done, essentially, is to take a conventional MRI and miniaturize it,” Yacoby said. “Functionally, it operates in the same way, but in doing that, we’ve had to change some of the components, and that has enabled us to achieve far greater resolution than conventional systems.”


Yacoby said that while conventional systems can achieve resolutions of less than a millimeter, they are effectively limited by the magnetic field gradient they can produce. Since those gradients fade dramatically within just feet, conventional systems built around massive magnets are designed to create a field large enough to image an object — like a human — that may be a meter or more in length.


The nanoscale system devised by Yacoby and colleagues, by comparison, uses a magnet that’s just 20 nanometers in diameter — about 300 times smaller than a red blood cell — but is able to generate a magnetic field gradient 100,000 times larger than even the most powerful conventional systems.

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New technique takes cues from astronomy and ophthalmology to sharpen microscope images

New technique takes cues from astronomy and ophthalmology to sharpen microscope images | Amazing Science | Scoop.it

The complexity of biology can befuddle even the most sophisticated light microscopes. Biological samples bend light in unpredictable ways, returning difficult-to-interpret information to the microscope and distorting the resulting image.


The approach, a form of adaptive optics, works in tissues that do not scatter light, making it well suited to imaging the transparent bodies of zebrafish and the roundworm Caenorhabditis elegans, important model organisms in biological research. Janelia group leader Eric Betzig says his team developed the new technology by combining adaptive optics strategies that astronomers and ophthalmologists use to cancel out similar distortions in their images.


In a report published online on April 13, 2014, in the journal Nature Methods, Betzig, postdoctoral fellow Kai Wang, and their colleagues show how the technique brings into focus the fine, branching structures and subcellular organelles of nerve cells deep in the living brain of a zebrafish. These structures remain blurry and indistinct under the same microscope without adaptive optics. "The results are pretty eye-popping," Betzig says. "This really takes the application of adaptive optics to microscopy to a completely different level."


"Our technique is really robust, and you don't need anything special to apply our technology. [In the future] it could be a very convenient add-on component to commercially available microscopes," says Wang, a postdoctoral researcher in Betzig's lab.


Via José Gonçalves
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A Possible Cure for Ebola Virus Infection Discovered: BCX4430

A Possible Cure for Ebola Virus Infection Discovered: BCX4430 | Amazing Science | Scoop.it

Ebola is one of the scariest viruses on Earth. Along with Marburg and a few other lesser known viruses, it is a member of the Filoviridae family, a nasty group of microbes that causes hemorrhagic fever. Like most viral diseases, patients with hemorrhagic fever will first present with flu-like symptoms. As the disease progresses, patients often bleed from their body orifices, such as their eyes and ears. Death, however, does not result from blood loss, but from shock or organ failure.


Hemorrhagic fevers are not easy to catch. Transmission generally requires prolonged contact with the patient or with his bodily fluids. Mortality rates depend on the particular viral strain. For Ebola, thedeadliest strain is Zaire, which can kill up to 90% of those infected. The worst ever outbreak occurred in Congo in 1976. That year, 318 people were infected and 280 died, a mortality rate of 88%. Currently, an outbreak of Ebola has killed at least 135 people in west Africa. The virus resembles Zaire, but researchers have determined that it is a brand new strain.


Obviously, finding a treatment or cure for such a frightening disease is desirable. With our highly interconnected world, it is only a matter of time before a hemorrhagic fever shows up on our doorstep. (Actually,that's already happened.) Unfortunately, at the present time, there is little that can be done for a victim of Ebola or any other hemorrhagic fever. Mostly, patients are kept hydrated and symptoms are treated as they arise. Other than that, doctors cross their fingers and hope the patient doesn't die.


That may be about to change. In the journal Nature, scientists -- who conducted much of their work in the secretive, high-containment biological laboratory maintained by USAMRIID at Fort Detrick, Maryland -- have reported the discovery of a small molecule that rescues rodents and monkeys from various hemorrhagic fevers. Even more, the drug exhibited activity against a wide range of viruses.


The molecule, named BCX4430, resembles the "A" found in DNA: adenosine. The RNA-based filoviruses also use "A" in their genomes. BCX4430, because it resembles "A", can be accidentally used by the virus when it is trying to grow inside of our cells. For the virus, this is a fatal mistake. BCX4430 blocks further growth and reproduction.


Shouldn't this drug be expected to hurt not only the virus, but humans as well? That would be a reasonable expectation, but for some reason, BCX4430 appears to only hurt the virus. Human cells appear not to be fooled by BCX4430 and do just fine in its presence. The most compelling experiment the research team ran involved the infection of cynomolgus macaque monkeys with deadly Marburg virus. Macaques were given twice daily doses of BCX4430 for 14 days beginning 1 hour, 24 hours, or 48 hours post-infection.


Amazingly, in vitro experiments showed that BCX4430 could potentially work against a wide range of viruses, including SARS, MERS, influenza, dengue, and measles.


Source: TK Warren et al. "Protection against filovirus diseases by a novel broad-spectrum nucleoside analogue BCX4430." Nature 508: 402-405 (2014). doi:10.1038/nature13027

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Stem-Cell Therapy for Blindness Is Moving Towards Clinical Trials

Stem-Cell Therapy for Blindness Is Moving Towards Clinical Trials | Amazing Science | Scoop.it
Advanced Cell Technology is testing a stem-cell treatment for blindness that could preserve vision and potentially reverse vision loss.


A new treatment for macular degeneration is close to the next stage of human testing—a noteworthy event not just for the millions of patients it could help, but for its potential to become the first therapy based on embryonic stem cells.


This year, the Boston-area company Advanced Cell Technology plans to move its stem-cell treatment for two forms of vision loss into advanced human trials. The company has already reported that the treatment is safe (see “Eye Study Is a Small but Crucial Advance for Stem-Cell Therapy”), although a full report of the results from the early, safety-focused testing has yet to be published. The planned trials will test whether it is effective. The treatment will be tested both on patients with Stargardt’s disease (an inherited form of progressive vision loss that can affect children) and on those with age-related macular degeneration, the leading cause of vision loss among people 65 and older.


Although complete data from the trials of ACT’s treatments have yet to be published, the company has reported impressive results with one patient, who recovered vision after being deemed legally blind. Now the company plans to publish the data from two clinical trials taking place in the U.S. and the E.U. in a peer-reviewed academic journal. Each of these early-stage trials includes 12 patients affected by either macular degeneration or Stargardt’s disease.


The more advanced trials will have dozens of participants, says ACT’s head of clinical development, Eddy Anglade. If proved safe and effective, the cellular therapy could preserve the vision of millions affected by age-related macular degeneration. By 2020, as the population ages, nearly 200 million people worldwide will have the disease, estimate researchers. Currently, there are no treatments available for the most common form, dry age-related macular degeneration.

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Lucile Debethune's curator insight, April 21, 3:50 AM

Je m'éloigne un peu des sujets de cybernétique mais pas si loin, car la bioingénierie est aussi un moyen technologique de modifier l'humain. Les cellules souches sont reprogrammes depuis quelques années, et on peut asssister à des sauts technologiques de plus en plus important, notamment avec l'utilisation de technologies comme les imprimantes 3D pour recréer des organes, gerer les relation avec des prothèses bioméchaniques, etc... 

Aun iveau de la vision plusieurs grands axes émergent, soit avec un "remède" comme ici (surtout face à la dégénration cellulaire due à certaines maladie ou à la vieillesse), soit avec des prothèses de plus en plus miniaturisées et reliées au cerveau. 

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Powdered alcohol to be sold in the US by fall 2014

Powdered alcohol to be sold in the US by fall 2014 | Amazing Science | Scoop.it
The federal government recently rubber-stamped the manufacture and sale of a Palcohol, which turns any liquid into your favorite adult beverage.


If you were looking forward to enjoying Palcohol, a powdered alcohol product, this fall, you may need to wait a bit longer. The Alcohol and Tobacco Tax and Trade Bureau granted Palcohol “label approval” on April 8, but rescinded its approval April 21 after this article was published. A representative with the bureau told the Associated Press that the original approvals were issued in error. Palcohol’s parent company Lipsmark will need to resubmit its labels for approval. [This update was published April 22, 2014]


Instantly turning water into an alcoholic beverage is no longer a feat of biblical proportions. Come fall, it will be legal for Americans to purchase powdered alcohol, which can turn water into rum, vodka or a variety of cocktails.


The product, called Palcohol, is the brainchild of alcohol enthusiast Mark Phillips. He invented the potent powder because he wanted an easy, portable way to enjoy an adult beverage after a day of hiking, biking or kayaking. The federal government recently gave its stamp of approval for the sale and manufacture of the product, and it could be on the shelves of your local liquor store in the fall.

The key to making alcohol powders are simple carbohydrates called cyclodextrins, which bind together to form donut-shaped structures. They can then absorb and encapsulate fluids, like alcohol, within their molecular “donut holes,” which allows the liquid to be handled as a water-soluble powder. Cyclodextrins are also used to dissolve insoluble medications, odor-fighting sprays, and reduced-fat foods. In the case of Palcohol, each packet weighs about an ounce — enough for one shot — and can fit into a pocket. The creators plan to release six flavors of Palcohol when it debuts later this year.
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Fast way to measure DNA repair – some people's DNA gets repaired 10 times faster than others

Fast way to measure DNA repair – some people's DNA gets repaired 10 times faster than others | Amazing Science | Scoop.it
Test analyzing cells’ ability to fix different kinds of broken DNA could help doctors predict cancer risk.


Our DNA is under constant attack from many sources, including environmental pollutants, ultraviolet light, and radiation. Fortunately, cells have several major DNA repair systems that can fix this damage, which may lead to cancer and other diseases if not mended.


The effectiveness of these repair systems varies greatly from person to person; scientists believe that this variability may explain why some people get cancer while others exposed to similar DNA-damaging agents do not. A team of MIT researchers has now developed a test that can rapidly assess several of these repair systems, which could help determine individuals’ risk of developing cancer and help doctors predict how a given patient will respond to chemotherapy drugs.


The new test, described in the Proceedings of the National Academy of Sciences the week of April 21, can analyze four types of DNA repair capacity simultaneously, in less than 24 hours. Previous tests have been able to evaluate only one system at a time.


“All of the repair pathways work differently, and the existing technology to measure each of those pathways is very different for each one. It takes expertise, it’s time-consuming, and it’s labor-intensive,” says Zachary Nagel, an MIT postdoc and lead author of the PNAS paper. “What we wanted to do was come up with one way of measuring all DNA repair pathways at the same time so you have a single readout that’s easy to measure.”


The research team, led by professor Leona Samson, used this approach to measure DNA repair in a type of immortalized human blood cells called lymphoblastoid cells, taken from 24 healthy people. They found a huge range of variability, especially in one repair system where some people’s cells were more than 10 times more efficient than others.


“None of the cells came out looking the same. They each have their own spectrum of what they can repair well and what they don’t repair well. It’s like a fingerprint for each person,” says Samson, who is the Uncas and Helen Whitaker Professor, an American Cancer Society Professor, and a member of MIT’s departments of biological engineering and of biology, Center for Environmental Health Sciences, and Koch Institute for Integrative Cancer Research.


With the new test, the MIT team can measure how well cells repair the most common DNA lesions, including single-strand breaks, double-strand breaks, mismatches, and the introduction of alkyl groups caused by pollutants such as fuel exhaust and tobacco smoke.


To achieve this, the researchers created five different circular pieces of DNA, four of which carry a specific type of DNA damage, also called DNA lesions. Each of these circular DNA strands, or plasmids, also carries a gene for a different colored fluorescent protein. In some cases, the DNA lesions prevent those genes from being expressed, so when the DNA is successfully repaired, the cell begins to produce the fluorescent protein. In others, repairing the DNA lesion turns the fluorescent gene off.


By introducing these plasmids into cells and reading the fluorescent output, scientists can determine how efficiently each kind of lesion has been repaired. In theory, more than five plasmids could go into each cell, but the researchers limited each experiment to five reporter plasmids to avoid potential overlap among colors. To overcome that limitation, the researchers are also developing an alternative tactic that involves sequencing the messenger RNA produced by cells when they copy the plasmid genes, instead of measuring fluorescence.

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Microscale gravity: Gravitational energy measured with 100,000 times better precision than in previous experiments

Microscale gravity: Gravitational energy measured with 100,000 times better precision than in previous experiments | Amazing Science | Scoop.it
Bouncing neutrons probe dark energy on a table-top, measuring gravity's effects at the quantum scale finds no deviations from Newton's laws.

In this week's Physical Review Letters2, a team led by physicist Hartmut Abele at the Technical University of Vienna shows that the ordinary laws of gravity are still valid even when measured over the scale of a few micrometres. The researchers measured quantized gravitational energy levels with a precision that is 100,000 times better than in previous experiments3.


That precision is sufficient to test some proposed explanations for dark energy — the unknown force that seems to be accelerating the expansion of the Universe. Some models of dark energy put constraints on particular gravity-like forces that would subtly distort the quantum levels at these micrometre scales. “It’s really a beautiful experimental tour de force,” says Geoffrey Greene, a physicist at the University of Tennessee in Knoxville who was not involved in the study.


'Chameleon' dark energy is one such hypothesized force. It derives its name from the way the range over which it acts is reduced drastically for dense objects, which would account for why we fail to see it in Solar System measurements. Such a 'fifth force', existing alongside the known electromagnetic, strong, weak and gravitational forces, would tweak the neutrons' energy levels from those predicted by gravity alone, says Amol Upadhye, a theoretical physicist at Ewha Womans University in Seoul, who was not part of the research team.


The team’s results put a limit on how strong that force could be. “This limit is one hundred times better than the previous such limit,” says Upadhye. This does not eliminate chameleon theories as possible explanations for the dark energy, he adds. “There are still some seven orders of magnitude to cover … but this goes a long way towards closing that gap.”


The results also constrain the properties of a potential candidate for dark matter, the substance thought to make up 85% of matter in the Universe but which seems to be undetectable except for its gravitational pull at cosmic scales. Very light hypothetical particles called axions would cause a deviation from the ordinary law of gravity at short distances. The absence of such an effect in this latest study limits how strong these interactions could be.


"It's truly remarkable that experiments such as this are possible at all," says Upadhye. The researchers call the technique gravity resonance spectroscopy, because it mirrors other kinds of spectroscopy, which measure the energy states of electrons in the electromagnetic field of an atom. These have found a wide range of uses — from determining the composition of faraway galactic objects to atomic clocks. “This first application of the new technology is a big step," says Greene.

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Wireless power transfer achieved for a 5-meter distance

Wireless power transfer achieved for a 5-meter distance | Amazing Science | Scoop.it
A great improvement has been demonstrated in the distance that electric power can travel wirelessly. Researchers developed the 'Dipole Coil Resonant System' for an extended range of inductive power transfer, up to 5 meters between transmitter and receiver coils. "Our technology proved the possibility of a new remote power delivery mechanism that has never been tried at such a long distance. Although the long-range wireless power transfer is still in an early stage of commercialization and quite costly to implement, we believe that this is the right direction for electric power to be supplied in the future. Just like we see Wi-Fi zones everywhere today, we will eventually have many Wi-Power zones at such places as restaurants and streets that provide electric power wirelessly to electronic devices," they say.


Chun T. Rim, a professor of Nuclear & Quantum Engineering at KAIST, and his team showcased, on April 16, 2014 at the KAIST campus, Daejeon, Republic of Korea, a great improvement in the distance that electric power can travel wirelessly. They developed the "Dipole Coil Resonant System (DCRS)" for an extended range of inductive power transfer, up to 5 meters between transmitter and receiver coils.


Since MIT's (Massachusetts Institute of Technology) introduction of the Coupled Magnetic Resonance System (CMRS) in 2007, which used a magnetic field to transfer energy for a distance of 2.1 meters, the development of long-distance wireless power transfer has attracted much attention for further research.


However, in terms of extending the distance of wireless power, CMRS, for example, has revealed technical limitations to commercialization that are yet to be solved: a rather complicated coil structure (composed of four coils for input, transmission, reception, and load); bulky-size resonant coils; high frequency (in a range of 10 MHz) required to resonate the transmitter and receiver coils, which results in low transfer efficiency; and a high Q factor of 2,000 that makes the resonant coils very sensitive to surroundings such as temperature, humidity, and human proximity.


Professor Rim proposed a meaningful solution to these problems through DCRS, an optimally designed coil structure that has two magnetic dipole coils, a primary one to induce a magnetic field and a secondary to receive electric power. Unlike the large and thick loop-shaped air coils built in CMRS, the KAIST research team used compact ferrite core rods with windings at their centers. The high frequency AC current of the primary winding generates a magnetic field, and then the linkage magnetic flux induces the voltage at the secondary winding.


Scalable and slim with a size of 3 m in length, 10 cm in width, and 20 cm in height, DCRS is significantly smaller than CMRS. The system has a low Q factor of 100, showing 20 times stronger against the environment changes, and works well at a low frequency of 100 kHz. The team conducted several experiments and achieved promising results: for instance, under the operation of 20 kHz, the maximum output power was 1,403 W at a 3-meter distance, 471 W at 4-meter, and 209 W at 5-meter. For 100 W of electric power transfer, the overall system power efficiency was 36.9% at 3 meters, 18.7% at 4 meters, and 9.2% at 5 meters.

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SpaceX's Reusable Falcon 9 Successfully Launches and Lands

SpaceX's Reusable Falcon 9 Successfully Launches and Lands | Amazing Science | Scoop.it
American space company SpaceX successfully tested a stage of what they hope will eventually become a reusable rocket, the Falcon 9 Reusable (F9R).


Even as its Falcon 9 rocket blasted its Dragon cargo capsule towards the International Space Station last Friday, aerospace company SpaceX was preparing another feat. On Monday April 21, SpaceX launched a variant of the Falcon 9 design from its facility in Texas. The rocket in question is a prototype of the Falcon 9 Reusable (F9R).


The F9R successfully blasted off and rose to an altitude of 250 meters. The rocket briefly hovered at that altitude before safely descending back to the launch pad. The entire maneuver was captured on video by a drone aircraft.


SpaceX intends the F9R design eventually to become the first stage of the Falcon 9 rocket; such reusability would substantially reduce the cost of space launches, which currently rely upon disposal rockets. Future assessments will see the F9R launched from SpaceX’s New Mexico test facility. During those evaluations, the rocket will be launched with the landing legs tucked away and to greater heights to more closely approximate conditions during an actual launch and landing.


In the meantime, SpaceX Dragon capsules will continue to ferry cargo, and eventually astronauts, to the space station. Friday’s launch was the third of 12 planned Dragon cargo runs to the station as part of SpaceX’s $1.6 billion contract with NASA.

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Asteroid and Meteorite Impacts Can Preserve Biodata for Millions of Years

Asteroid and Meteorite Impacts Can Preserve Biodata for Millions of Years | Amazing Science | Scoop.it

In two separate studies, geologists led by Dr. Haley Sapers from the University of Western Ontario and Dr. Pete Schultz of Brown University have found floral, microbial and organic matter in glass created by ancient asteroid, comet and meteorite impacts. Such glass samples could provide a snapshot of environmental conditions at the time of those impacts and could be a good place to look for signs of ancient life on Mars.


In the first study, published in the journal Geology, Dr Schultz with colleagues found fragments of leaves and preserved organic compounds lodged inside glass created by a several ancient impacts in Argentina. “The soil of eastern Argentina, south of Buenos Aires, is rife with impact glass created by at least seven different impacts that occurred between 6,000 and 9 million years ago,” Dr Schultz explained. “One of those impacts, dated to around 3 million years ago, coincides with the disappearance of 35 animal genera.”

“We know these were major impacts because of how far the glass is distributed and how big the chunks are. These glasses are present in different layers of sediment throughout an area about the size of Texas,” he said.


Within glass associated with two of those impacts – one from 3 million years ago and one from 9 million years ago – the team found exquisitely preserved plant matter.


In the second study, published also in the journal Geology, Dr Sapers and her colleagues discovered microbes preserved in impact glass. They analyzed tubular features in hydrothermally altered impact glass from the Ries Impact Structure, Germany, that are remarkably similar to the bioalteration textures observed in volcanic glasses.


Mineral-forming processes cannot easily explain the distribution and shapes of the Ries tubular features; therefore, they suggest the tubules formed by microbes etching their way through the impact glass as they excreted organic acids.


A meteorite impact into a water-rich target such as Earth or Mars has the potential to generate a post-impact hydrothermal system.

Impact structures, especially post-impact hydrothermal systems, represent an understudied habitat with potential relevance to early life and the evolution of early life on Earth.


Understanding the biological significance of impact products such as impact glass on Earth will better inform the search for evidence of life and past life on other terrestrial planets such as Mars.

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Global Soundscapes: Help Scientists Record One Day of Sound on Earth

Global Soundscapes: Help Scientists Record One Day of Sound on Earth | Amazing Science | Scoop.it

Bryan Pijanowski wants to capture the sounds of the world on a single day, and he needs your help. Beginning on Earth Day, April 22 of this year, Pijanowski hopes to enlist thousands of people in recording a few minutes of their everyday surroundings with his Soundscape Recorder smartphone app.


All those sonic snippets could create an unprecedented soundtrack to life on Earth — and as they accumulate, year after year, scientists could use them to measure patterns and changes in our sonic environments.


“I’ve been on a campaign to record as many ecosystems as possible,” said Pijanowski, a soundscape ecologist at Purdue University. “But there’s only so many places in the world I can be. I thought about how I could get more recordings into a database, and it occurred to me: We have a couple billion people on this planet with smartphones!”


Pijanowski’s work typically takes him to places like the Sonoran desert or old-growth rain forests in Borneo, where he analyzes recordings to learn more about ecosystem health and dynamics: relationships between biodiversity and forest canopy structure, or how natural communities recover from wildfire.


With the Global Soundscape project and its Soundscape Recorder app, now available for iOS and Android devices, the emphasis is on cities and towns and suburbs, and our relationships to their sonic character.


After making a recordings with the app, people are asked a short series of questions about what they heard and how they feel. The recording is then uploaded to the Global Soundscape database. “If we make this part of the Earth Day culture, something everyone goes out and does, we can begin to characterize those sounds and compare them from year to year,” said Pijanowski.

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Today’s Antarctic region once as hot as California or Florida

Today’s Antarctic region once as hot as California or Florida | Amazing Science | Scoop.it

Parts of ancient Antarctica were as warm as today’s California coast, and polar regions of the southern Pacific Ocean registered 21st-century Florida heat, according to scientists using a new way to measure past temperatures.


The findings, published the week of April 21, 2014 in the Proceedings of the National Academy of Sciences, underscore the potential for increased warmth at Earth’s poles and the associated risk of melting polar ice and rising sea levels, the researchers said.


Led by scientists at Yale, the study focused on Antarctica during the Eocene epoch, 40-50 million years ago, a period with high concentrations of atmospheric CO2 and consequently a greenhouse climate. Today, Antarctica is year-round one of the coldest places on Earth, and the continent’s interior is the coldest place, with annual average land temperatures far below zero degrees Fahrenheit.


But it wasn’t always that way, and the new measurements can help improve climate models used for predicting future climate, according to co-author Hagit Affek of Yale, associate professor of geology & geophysics.


“Quantifying past temperatures helps us understand the sensitivity of the climate system to greenhouse gases, and especially the amplification of global warming in polar regions,” Affek said.

The paper’s lead author, Peter M.J. Douglas, performed the research as a graduate student in Affek’s Yale laboratory. He is now a postdoctoral scholar at the California Institute of Technology. The research team included paleontologists, geochemists, and a climate physicist.


By measuring concentrations of rare isotopes in ancient fossil shells, the scientists found that temperatures in parts of Antarctica reached as high as 17 degrees Celsius (63F) during the Eocene, with an average of 14 degrees Celsius (57F)  — similar to the average annual temperature off the coast of California today.

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Identical twins, one with Down syndrome the other one without: a genetic mystery

Identical twins, one with Down syndrome the other one without: a genetic mystery | Amazing Science | Scoop.it
A rare occurrence in the earliest days of a pregnancy produces an unusual and mystifying outcome: Identical twin fetuses are conceived of the same meeting of egg and sperm. And despite their shared DNA, one of the twins has Down syndrome (the most common genetic cause of intellectual impairment), but the other does not.


But these aborted identical twins -- one with an extra copy of chromosome 21 and the other without -- offered scientists a remarkable opportunity: given the twin fetuses' otherwise exact DNA match, how would this one difference translate across the genome?


That natural experiment allowed a group of geneticists from Switzerland, Spain, the Netherlands and France to distill some fundamental insights into how chromosomes -- and the genetic blueprints they contain -- dictate the behavior of cells across the body. They found that when gene expression is altered by, say, an added chromosome, it is altered in consistent patterns in every chromosome, not just the one with the irregularity.


A few things follow from that: First, it lends credence to scientists' long-running suspicion that chromosomes -- between 50 and 100 base pairs of DNA -- may be organized along functional lines, such that certain stretches of a chromosome may hold the genetic blueprint for proteins that work together in some predictable way. If they are organized functionally, they're not random. And if they're not random, they can (someday) be understood.


Trisomy 21 is the most frequent genetic cause of cognitive impairment. To assess the perturbations of gene expression in trisomy 21, and to eliminate the noise of genomic variability, we studied the transcriptome of fetal fibroblasts from a pair of monozygotic twins discordant for trisomy 21. Here we show that the differential expression between the twins is organized in domains along all chromosomes that are either upregulated or downregulated. These gene expression dysregulation domains (GEDDs) can be defined by the expression level of their gene content, and are well conserved in induced pluripotent stem cells derived from the twins’ fibroblasts. Comparison of the transcriptome of the Ts65Dn mouse model of Down’s syndrome and normal littermate mouse fibroblasts also showed GEDDs along the mouse chromosomes that were syntenic in human. The GEDDs correlate with the lamina-associated (LADs) and replication domains of mammalian cells. The overall position of LADs was not altered in trisomic cells; however, the H3K4me3 profile of the trisomic fibroblasts was modified and accurately followed the GEDD pattern. These results indicate that the nuclear compartments of trisomic cells undergo modifications of the chromatin environment influencing the overall transcriptome, and that GEDDs may therefore contribute to some trisomy 21 phenotypes.

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Ripples in Quantum Sand: SLAC Scientists View Ultrafast Snapshots of Light-Driven Superconductivity

Ripples in Quantum Sand: SLAC Scientists View Ultrafast Snapshots of Light-Driven Superconductivity | Amazing Science | Scoop.it

Scientists at SLAC National Accelerator Laboratory's Linac Coherent Light Source used carefully timed pairs of laser pulses to capture ultrafast snapshots of light-driven superconductivity.


A new study pins down a major factor behind the appearance of superconductivity – the ability to conduct electricity with 100 percent efficiency – in a promising copper-oxide material. Scientists used carefully timed pairs of laser pulses at SLAC National Accelerator Laboratory’s Linac Coherent Light Source (LCLS) to trigger superconductivity in the material and immediately take X-ray snapshots of its atomic and electronic behavior as superconductivity emerged.


They discovered that so-called “charge stripes” of increased electrical charge melted away as superconductivity appeared. Further, the results help rule out the theory that shifts in the material’s atomic lattice hinder the onset of superconductivity.


Armed with this new understanding, scientists may be able to develop new techniques to eliminate these charge stripes and help pave the way for room-temperature superconductivity, often considered the holy grail of condensed matter physics. The demonstrated ability to rapidly switch between the insulating and superconducting states could also prove useful in advanced electronics and computation.


The results, from a collaboration led by scientists from the Max Planck Institute for the Structure and Dynamics of Matter in Germany and the U.S. Department of Energy’s SLAC and Brookhaven national laboratories, were published online April 16, 2014, in the journal Physical Review Letters.


“The very short timescales and the need for high spatial resolution made this experiment extraordinarily challenging,” said co-author Michael Först, a scientist at the Max Planck Institute. “Now, using femtosecond X-ray pulses, we found a way to capture the quadrillionths-of-a-second dynamics of the charges and the crystal lattice. We’ve broken new ground in understanding light-induced superconductivity.”


Josh Turner, an LCLS staff scientist, said, “This represents a very important result in the field of superconductivity using LCLS. It demonstrates how we can unravel different types of complex mechanisms in superconductivity that have, up until now, been inseparable.”


He added, “To make this measurement, we had to push the limits of our current capabilities. We had to measure a very weak, barely detectable signal with state-of-the-art detectors, and we had to tune the number of X-rays in each laser pulse to see the signal from the stripes without destroying the sample.”


Ripples in Quantum Sand: The compound used in this study was a layered material consisting of lanthanum, barium, copper, and oxygen grown at Brookhaven Lab by physicist Genda Gu. Each copper oxide layer contained the crucial charge stripes.


“Imagine these stripes as ripples frozen in the sand,” said John Hill, a Brookhaven Lab physicist and coauthor on the study. “Each layer has all the ripples going in one direction, but in the neighboring layers they run crosswise. From above, this looks like strings in a pile of tennis racquets. We believe that this pattern prevents each layer from talking to the next, thus frustrating superconductivity.”

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Researchers Develop Spaser Made of Graphene and Carbon Nanotubes

Researchers Develop Spaser Made of Graphene and Carbon Nanotubes | Amazing Science | Scoop.it
Researchers from Monash University have developed a spaser using graphene and carbon nanotubes, showing that graphene and carbon nanotubes can interact and transfer energy to each other through light.


A new version of “spaser” technology being investigated could mean that mobile phones become so small, efficient, and flexible they could be printed on clothing.


A team of researchers from Monash University’s Department of Electrical and Computer Systems Engineering (ECSE) has modeled the world’s first spaser (surface plasmon amplification by stimulated emission of radiation) to be made completely of carbon.


A spaser is effectively a nanoscale laser or nanolaser. It emits a beam of light through the vibration of free electrons, rather than the space-consuming electromagnetic wave emission process of a traditional laser.

PhD student and lead researcher Chanaka Rupasinghe said the modeled spaser design using carbon would offer many advantages.


“Other spasers designed to date are made of gold or silver nanoparticles and semiconductor quantum dots while our device would be comprised of a graphene resonator and a carbon nanotube gain element,” Chanaka said.


“The use of carbon means our spaser would be more robust and flexible, would operate at high temperatures, and be eco-friendly. “Because of these properties, there is the possibility that in the future an extremely thin mobile phone could be printed on clothing.”


Spaser-based devices can be used as an alternative to current transistor-based devices such as microprocessors, memory, and displays to overcome current miniaturizing and bandwidth limitations.


The researchers chose to develop the spaser using graphene and carbon nanotubes. They are more than a hundred times stronger than steel and can conduct heat and electricity much better than copper. They can also withstand high temperatures.


Their research showed for the first time that graphene and carbon nanotubes can interact and transfer energy to each other through light. These optical interactions are very fast and energy-efficient, and so are suitable for applications such as computer chips.


“Graphene and carbon nanotubes can be used in applications where you need strong, lightweight, conducting, and thermally stable materials due to their outstanding mechanical, electrical and optical properties. They have been tested as nanoscale antennas, electric conductors and waveguides,” Chanaka said.


Via José Gonçalves
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Artificial blood 'will be manufactured in factories', paving the way for mass production of blood

Artificial blood 'will be manufactured in factories', paving the way for mass production of blood | Amazing Science | Scoop.it

Wellcome Trust-funded stem cell research has produced red blood cells fit for transfusion into humans, paving the way for the mass production of blood.


It is the stuff of gothic science fiction: men in white coats in factories of blood and bones. But the production of blood on an industrial scale could become a reality once a trial is conducted in which artificial blood made from human stem cells is tested in patients for the first time.


It is the latest breakthrough in scientists’ efforts to re-engineer the body, which have already resulted in the likes of 3d-printed bones and bionic limbs. Marc Turner, the principal researcher in the £5 million program funded by the Wellcome Trust, told The Telegraph that his team had made red blood cells fit for clinical transfusion.

Prof Turner has devised a technique to culture red blood cells from induced pluripotent stem (iPS) cells – cells that have been taken from humans and ‘rewound’ into stem cells. Biochemical conditions similar to those in the human body are then recreated to induce the iPS cells to mature into red blood cells – of the rare universal blood type O-.


“Although similar research has been conducted elsewhere, this is the first time anybody has manufactured blood to the appropriate quality and safety standards for transfusion into a human being,” said Prof Turner. There are plans in place for the trial to be concluded by late 2016 or early 2017, he said. It will most likely involve the treatment of three patients with Thalassaemia, a blood disorder requiring regular transfusions. The behavior of the manufactured blood cells will then be monitored.


“The cells will be safe,” he said, adding that there are processes whereby cells can be removed. The technique highlights the prospect of a limitless supply of manufactured type O- blood, free of disease and compatible with all patients.


“Although blood banks are well-stocked in the UK and transfusion has been largely safe since the Hepatitis B and HIV infections of the 1970s and 1980s, many parts of the world still have problems with transfusing blood,” said Prof Turner.

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Distant Black Hole Spins at Half the Speed of Light

Distant Black Hole Spins at Half the Speed of Light | Amazing Science | Scoop.it
Back when the universe was half its present age, supermassive black holes were feeding from a steady and plentiful diet of neighboring galaxies, the first measurement of a distant supermassive black hole’s spin shows.


Taking advantage of a naturally occurring zoom lens in space, astronomers analyzed X-rays streaming from near the mouth of a supermassive black hole powering a quasar about 6 billion light years from Earth.


“The ‘lens’ galaxy acts like a natural telescope, magnifying the light from the faraway quasar,” University of Michigan astronomer Rubens Reis explains in a paper published in this week’s Nature.


Analyzing four magnified images created by the lens galaxy -- an elliptical galaxy about 3 billion light years away -- Reis and colleagues found that the quasar’s black hole is spinning at half the speed of light.


The spin rate directly relates to how black holes feed and grow: The steadier the diet, the faster the spin, computer models show. “If the mass accretion was more messy it would suggest that the black hole would have a lower spin,” astronomer Mark Reynolds, also with University of Michigan, told Discovery News.


“What we found in this system is that it’s spinning very rapidly,” Reynolds said, consuming mass equivalent to about one sun per year. Spin rates may evolve over time, reflecting changes in evolution of galaxies.


At some distance, the black holes’ spins might be even higher, approaching light speed, and then slow down to RX J1131’s spin rate.


“If we go back further, maybe they’ll all be maximally spinning because of more mergers and more things happening. Or maybe they’ll be less spinning. We can theoretically produce both scenarios at the moment,” Reynolds said.


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