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Most abundant ocean viruses attack bacteria that are important for the carbon cycle

Most abundant ocean viruses attack bacteria that are important for the carbon cycle | Amazing Science | Scoop.it

In one corner is the Earth’s most abundant organism: SAR11, an ocean-living bacterium that survives where most other cells would die and plays a major role in the planet’s carbon cycle. It had been theorized that SAR11 was so small and widespread that it must be invulnerable to attack.

 

In the other corner, and so strange looking that scientists previously didn’t even recognize what they were, are “Pelagiphages,” viruses now known to infect SAR11 and routinely kill millions of these cells every second.

 

How this fight turns out is of more than casual interest, because SAR11 has a huge effect on the amount of carbon dioxide that enters the atmosphere, and the overall biology of the oceans.

 

“There’s a war going on in our oceans, a huge war, and we never even saw it,” says Stephen Giovannoni, a professor of microbiology at Oregon State University. “This is an important piece of the puzzle in how carbon is stored or released in the sea.” The analysis shows that the new viruses—like their hosts—are the most abundant on record.

 

The paper in Nature describes four previously unknown viruses that infect SAR11. To prove the viruses were as abundant as their hosts, Giovannoni and colleagues teamed up with researchers at the University of Arizona’s Tucson Marine Phage Research Lab, led by Matthew Sullivan, who had developed accurate methods for measuring viral diversity in nature.

 

The analysis shows that the new viruses—like their hosts—are the most abundant on record. Giovannoni’s group discovered the Pelagiphage viral families by using “old-fashioned” research methods, growing the cells and viruses in a laboratory, instead of the tools of modern genomics, and found the new type of virus.

 

“Because they are so new, these viruses were virtually unrecognizable to us based on their DNA,” Giovannoni says. “The viruses themselves, of course, appear to be just as abundant as SAR11.”

 

Sullivan explains the method for discovering viruses in the oceans based on their genomes his group developed over four years is at least 1,000 times more accurate than previous methods.

 

Their work resulted in the Pacific Ocean Virus dataset. This dataset, Sullivan explains, is the viral equivalent of the Global Ocean Sampling Expedition by former human genome researcher J. Craig Venter, who sailed across the world’s oceans sampling, sequencing, and analyzing the DNA of the microorganisms living in these waters. The new findings on SAR11 disprove the theory that the bacteria are immune to viral predation, Giovannoni and his co-authors say.

 

“In general, every living cell is vulnerable to viral infection,” says Giovannoni, who first discovered SAR11 in 1990. “What has been so puzzling about SAR11 was its sheer abundance, there was simply so much of it that some scientists believed it must not get attacked by viruses.” What the new research shows, Giovannoni says, is that SAR11 is competitive, good at scavenging organic carbon, and effective at changing quickly to avoid infection. Because of this, it thrives and persists in abundance even though the new viruses are constantly killing it.

 

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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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Siegfried Holle's curator insight, July 4, 2014 8:45 AM

Your knowledge is your strength and power 

Saberes Sin Fronteras OVS's curator insight, November 30, 2014 5:33 PM

Acceso gratuito a documentos de las mejores universidades del mundo

♥ princess leia ♥'s curator insight, December 28, 2014 11:58 AM

WoW  .. Expand  your mind!! It has room to grow!!! 

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New nonlinear SIM microscope gives deepest view yet of living cells

New nonlinear SIM microscope gives deepest view yet of living cells | Amazing Science | Scoop.it

Two new microscopy techniques are helping scientists see smaller structures in living cells than ever glimpsed before.


Scientists can now view structures just 45 to 84 nanometers wide, Nobel prize-winning physicist Eric Betzig of the Howard Hughes Medical Research Institute’sJanelia research campus in Ashburn, Va., and colleaguesreport in the Aug. 28 Science. The techniques beat the previous resolution of 100 nanometers and shatters the 250 nanometer “diffraction barrier,” imposed by the bending of light.


Using other tricks to improve the super-resolution methods also allowed the researchers to take ultraquick pictures with less cell-damaging light than before. As a result, scientists can watch sub-second interactions within cells, revealing new insights into how cells work.

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AGM2015: High-Precision Antineutrino Global Map 2015

AGM2015: High-Precision Antineutrino Global Map 2015 | Amazing Science | Scoop.it

Every second greater than 10E25 antineutrinos radiate to space from Earth, shining like a faint antineutrino star. Underground antineutrino detectors have revealed the rapidly decaying fission products inside nuclear reactors, verified the long-lived radioactivity inside our planet, and informed sensitive experiments for probing fundamental physics. Mapping the anisotropic antineutrino flux and energy spectrum advance geoscience by defining the amount and distribution of radioactive power within Earth while critically evaluating competing compositional models of the planet. A group of scientists now present the Antineutrino Global Map 2015 (AGM2015), an experimentally informed model of Earth’s surface antineutrino flux over the 0 to 11 MeV energy spectrum, along with an assessment of systematic errors. The open source AGM2015 provides fundamental predictions for experiments, assists in strategic detector placement to determine neutrino mass hierarchy, and aids in identifying undeclared nuclear reactors. They use cosmo-chemically and seismologically informed models of the radiogenic lithosphere/mantle combined with the estimated antineutrino flux, as measured by KamLAND and Borexino, to determine the Earth’s total antineutrino luminosity. They find a dominant flux of geo-neutrinos, predict sub-equal crust and mantle contributions, with ~1% of the total flux from man-made nuclear reactors.

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New solar cell absorbs high-energy blue light at 30-fold higher concentration than conventional cells

New solar cell absorbs high-energy blue light at 30-fold higher concentration than conventional cells | Amazing Science | Scoop.it
By combining designer quantum dot light-emitters with spectrally matched photonic mirrors, a team of scientists with Berkeley Lab and the University of Illinois created solar cells that collect blue photons at 30 times the concentration of conventional solar cells, the highest luminescent concentration factor ever recorded. This breakthrough paves the way for the future development of low-cost solar cells that efficiently utilize the high-energy part of the solar spectrum.


"We've achieved a luminescent concentration ratio greater than 30 with an optical efficiency of 82-percent for blue photons," says Berkeley Lab director Paul Alivisatos, who is also the Samsung Distinguished Professor of Nanoscience and Nanotechnology at the University of California Berkeley, and director of the Kavli Energy Nanoscience Institute (ENSI), was the co-leader of this research. "To the best of our knowledge, this is the highest luminescent concentration factor in literature to date."


Alivisatos and Ralph Nuzzo of the University of Illinois are the corresponding authors of a paper in ACS Photonics describing this research entitled "Quantum Dot Luminescent Concentrator Cavity Exhibiting 30-fold Concentration." Noah Bronstein, a member of Alivisatos's research group, is one of three lead authors along with Yuan Yao and Lu Xu. Other co-authors are Erin O'Brien, Alexander Powers and Vivian Ferry.


The solar energy industry in the United States is soaring with the number of photovoltaic installations having grown from generating 1.2 gigawatts of electricity in 2008 to generating 20-plus gigawatts today, according to the U.S. Department of Energy (DOE). Still, nearly 70-percent of the electricity generated in this country continues to come from fossil fuels. Low-cost alternatives to today's photovoltaic solar panels are needed for the immense advantages of solar power to be fully realized. One promising alternative has been luminescent solar concentrators (LSCs).


Unlike conventional solar cells that directly absorb sunlight and convert it into electricity, an LSC absorbs the light on a plate embedded with highly efficient light-emitters called "lumophores" that then re-emit the absorbed light at longer wavelengths, a process known as the Stokes shift. This re-emitted light is directed to a micro-solar cell for conversion to electricity. Because the plate is much larger than the micro-solar cell, the solar energy hitting the cell is highly concentrated.


With a sufficient concentration factor, only small amounts of expensive III−V photovoltaic materials are needed to collect light from an inexpensive luminescent waveguide. However, the concentration factor and collection efficiency of the molecular dyes that up until now have been used as lumophores are limited by parasitic losses, including non-unity quantum yields of the lumophores, imperfect light trapping within the waveguide, and reabsorption and scattering of propagating photons.


"We replaced the molecular dyes in previous LSC systems with core/shell nanoparticles composed of cadmium selenide (CdSe) cores and cadmium sulfide (CdS) shells that increase the Stokes shift while reducing photon re-absorption," says Bronstein.

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Gene therapy rescues dying cells in the brains of Alzheimer's patients

Gene therapy rescues dying cells in the brains of Alzheimer's patients | Amazing Science | Scoop.it

An experimental gene therapy reduces the rate at which nerve cells in the brains of Alzheimer’s patients degenerate and die, according to new results from a small clinical trial, published in the current issue of the journal JAMA Neurology.


Targeted injection of the Nerve Growth Factor gene into the patients’ brains rescued dying cells around the injection site, enhancing their growth and inducing them to sprout new fibres. In some cases, these beneficial effects persisted for 10 years after the therapy was first delivered.


Alzheimer’s is the world’s leading form of dementia, affecting an estimated 47 million people worldwide. This figure is predicted to almost double every 20 years, with much of this increase is likely to be in the developing world. And despite the huge amounts of time, effort, and money devoted to developing an effective cure, the vast majority of new drugs have failed in clinical trials.


The new results are preliminary findings from the very first human trials designed to test the potential benefits of nerve growth factor (NGF) gene therapy for Alzheimer’s patients.


NGF was discovered in the 1940s by Rita Levi-Montalcini, who convincingly demonstrated that the small protein promotes the survival of certain sub-types of sensory neurons during development of the nervous system. Since then, others have shown that it also promotes the survival of acetylcholine-producing cells in the basal forebrain, which die off in Alzheimer’s.


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New, Ultrathin Optical Devices Shape Light in Exotic Ways

New, Ultrathin Optical Devices Shape Light in Exotic Ways | Amazing Science | Scoop.it
Caltech engineers have created flat devices capable of manipulating light in ways that are very difficult or impossible to achieve with conventional optical components.

The new devices are not made of glass, but rather of silicon nanopillars that are precisely arranged into a honeycomb pattern to create a "metasurface" that can control the paths and properties of passing light waves.

These metasurface devices, described in a paper published online on August 31, 2015, in the journal Nature Nanotechnology, could lead to ultracompact optical systems such as advanced microscopes, displays, sensors, and cameras that can be mass-produced using the same photolithography techniques used to manufacture computer microchips.

"Currently, optical systems are made one component at a time, and the components are often manually assembled," says Andrei Faraon (BS '04), an assistant professor of applied physics and materials science, and the study's principal investigator. "But this new technology is very similar to the one used to print semiconductor chips onto silicon wafers, so you could conceivably manufacture millions of systems such as microscopes or cameras at a time."

Seen under a scanning electron microscope, the new metasurfaces that the team created resemble a cut forest where only the stumps remain. Each silicon stump, or pillar, has an elliptical cross section, and by carefully varying the diameters of each pillar and rotating them around their axes, the scientists were able to simultaneously manipulate the phase and polarization of passing light. Light is an electromagnetic field, and the field of single-color, or monochromatic, light oscillates at all points in space with the same frequency but varying relative delays, or phases.
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Evidence of ancient microbial life discovered in mantle rocks deep below the seafloor

Evidence of ancient microbial life discovered in mantle rocks deep below the seafloor | Amazing Science | Scoop.it
Ancient rocks harbored microbial life deep below the seafloor, reports a team of scientists from the Woods Hole Oceanographic Institution (WHOI), Virginia Tech, and the University of Bremen. This new evidence was contained in drilled rock samples of Earth's mantle - thrust by tectonic forces to the seafloor during the Early Cretaceous period. The new study was published today in the Proceedings of the National Academy of Sciences.


The discovery confirms a long-standing hypothesis that interactions between mantle rocks and seawater can create potential for life even in hard rocks deep below the ocean floor. The fossilized microbes are likely the same as those found at the active Lost City hydrothermal field, providing potentially important clues about the conditions that support 'intraterrestrial' life in rocks below the seafloor.


"We were initially looking at how seawater interacts with mantle rocks, and how that process generates hydrogen," said Frieder Klein, an associate scientist at WHOI and lead author of the study. "But during our analysis of the rock samples, we discovered organic-rich inclusions that contained lipids, proteins and amino acids - the building blocks of life - mummified in the surrounding minerals."


This study, which was a collaborative effort between Klein, WHOI scientists Susan Humphris, Weifu Guo and William Orsi, Esther Schwarzenbach from Virginia Tech and Florence Schubotz from the University of Bremen, focused on mantle rocks that were originally exposed to seawater approximately 125 million years ago when a large rift split the massive supercontinent known as Pangaea. The rift, which eventually evolved into the Atlantic Ocean, pulled mantle rocks from Earth's interior to the seafloor, where they underwent chemical reactions with seawater, transforming the seawater into a hydrothermal fluid.


"The hydrothermal fluid likely had a high pH and was depleted in carbon and electron acceptors," Klein said. "These extreme chemical conditions can be challenging for microbes. However, the hydrothermal fluid contained hydrogen and methane and seawater contains dissolved carbon and electron acceptors. So when you mix the two in just the right proportions, you can have the ingredients to support life."

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Neuroscientists Find New Brain Network

Neuroscientists Find New Brain Network | Amazing Science | Scoop.it

Humans abound with remarkable skills: we write novels, build bridges, compose symphonies, and even navigate Boston traffic. But despite our mental prowess, we share a surprising deficit: our working memory can track only four items at one time.


“Would you buy a computer with a RAM capacity of 4?” asks David Somers, professor and chair of the Department of Psychological & Brain Sciences. “Not 4 MB or GB or 4K—just 4. So how the heck do humans do all this stuff?”


“There’s so much information out there, and our brains are very limited in what we’re able to process,” adds Samantha Michalka, a postdoctoral fellow at the Center for Computational Neuroscience & Neural Technology. “We desperately need attention to function in the world.”


Michalka is lead author and Somers is senior author of a new study that sheds light on this enduring mystery of neuroscience: how humans achieve so much with such limited attention. Funded by the National Science Foundation (NSF) and the National Institutes of Health (NIH), the work identifies a previously unknown attention network in the brain. It also reveals that our working memory for space and time can recruit our extraordinary visual and auditory processing networks when needed. The research appeared on August 19, 2015, in the journal Neuron.


Prior to this work, scientists believed that visual information from the eyes and auditory information from the ears merged before reaching the frontal lobes, where abstract thought occurs. The team of BU scientists, which also included Auditory Neuroscience Laboratory Director Barbara Shinn-Cunningham, performed functional MRI experiments to test the conventional wisdom. The experiments revealed that what was thought to be one large attention network in the frontal lobe is actually two interleaved attention networks, one supporting vision and one supporting hearing. “So instead of talking about a single attention network,” says Somers, “we now need to talk about a visual attention network and an auditory attention network that work together.”

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Sandeep Gautam's curator insight, August 30, 11:33 PM

an auditory attention network along with a visual attention network!

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Super-low loss quantum energy transport could revolutionize sunlight to energy conversion

Super-low loss quantum energy transport could revolutionize sunlight to energy conversion | Amazing Science | Scoop.it

The use of sunlight as an energy source is achieved in a number of ways, from conversion to electricity via photovoltaic (PV) panels, concentrated heat to drive steam turbines, and even hydrogen generation via artificial photosynthesis. Unfortunately, much of the light energy in PV and photosynthesis systems is lost as heat due to the thermodynamic inefficiencies inherent in the process of converting the incoming energy from one form to another. Now scientists working at the University of Bayreuth claim to have created a super-efficient light-energy transport conduit that exhibits almost zero loss, and shows promise as the missing link in the sunlight to energy conversion process.


Using specifically-generated nanofibers at its core, this is reported to be the very first time a directed energy transport system has been exhibited that effectively moves intact light energy over a distance of several micrometers, and at room temperature. And, according to the researchers, the transference of energy from block to block in the nanofibers is only adequately explained at the quantum level with coherence effects driving the energy along the individual fibers.


Quantum coherence is the phenomenon where subatomic waves are closely interlinked via shared electromagnetic fields. As they travel in phase together, these quantum coherent waves start to act as one very large synchronous wave propagating across a medium. In the case of the University of Bayreuth device, these coherent waves of energy travel across the molecular building blocks from which the nanofibers are made, passing from block to block and moving as one continuous energy wave would in unbound free space.


It is this effect that the scientists say is driving the super-low energy loss capabilities of their device, and have confirmed this observation using a variety of microscopy techniques to visualize the conveyance of excitation energy along the nanofibers. The nanofibers themselves are specifically-prepared supramolecular strands, manufactured from a chemically bespoke combination of carbonyl-bridged (molecularly connected) triarylamine (an organic compound) combined with three naphthalimide bithiophene chromophores (copolymer molecules that absorb and reflect specific wavelengths of light). When brought together under particular conditions, these elements spontaneously self-assemble into 4 micrometer long, 0.005 micrometer diameter nanofibers made up of more than 10,000 identical chemical building blocks.


"These highly promising nanostructures demonstrate that carefully tailoring materials for the efficient transport of light energy is an emerging research area," said Dr. Richard Hildner, an experimental physicist at the University of Bayreuth. The results of this research were recently published in the journal Nature.

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Revealed: How did our planet ever escape 'snowball Earth'?

Revealed: How did our planet ever escape 'snowball Earth'? | Amazing Science | Scoop.it
Glaciers once covered most of Earth's surface and reflected the sun's heat back into space.


New details of a nightmare period on Earth with surface conditions as frigid as present-day central Antarctica at the equator have been revealed thanks to the publication of a study of ancient glacier water. The research, by an international team led by Daniel Herwartz, is published in the journal Proceedings of the National Academy of Sciences and shows that even tropical regions were once covered in snow and ice.


The idea of a deep-frozen world, “snowball Earth”, has captured the imagination since first proposed in the 1990s. On several occasions in history, long before animals evolved, apparently synchronous ice sheets existed on all the continents. However, much like falling into a crevasse on a glacier, it’s easy enough to enter such an ice age, but very difficult to escape.


The snowball Earth theory came from climate modelers who found that low carbon dioxide levels could trigger the growth of ice sheets. The whole planet would become glaciated and its mean temperature drop to as low as -45°C. As ice is much more reflective than the sea, or bare land, the Earth at that point would have been bouncing nearly all of the sun’s radiation back into space. So how could the planet ever emerge from such an ice age?


Volcanoes had to be the answer. Only they could emit enough carbon dioxide into the atmosphere to overcome the effects of Earth’s cool reflective surface. But climate models still found it difficult to plausibly describe how the Earth could have shed its glaciers.


We now have the first full explanation for how the best-known snowball event, the Marinoan, finished 635 million years ago with a several hundred meter rise in sea level. The study is the result of work by an international team of scientists. The results are published in the journal Nature Geoscience.


The team of researchers found slight wobbles of the Earth’s spin axis caused differences in the heat received at different places on the planet’s surface. These changes were small, but enough over thousands of years to cause a change in the places where snow accumulated or melted, leading the glaciers to advance and retreat.


The Earth was left looking just like the McMurdo Dry Valleys in Antarctica – arid, with lots of bare ground, but also containing glaciers up to 3 km thick. Such an Earth would have been darker than previously envisaged, absorbing more of the sun’s radiation; it was easier to see how the escape from the snowball happened.


Today, to find exposed rocks that can tell us about the carbon dioxide content of the atmosphere in the Marinoan, you have to go to the Norwegian Arctic island of Svalbard. In 2009 snowball theory was vindicated after we found the telltale signal of high carbon dioxide levels in Svalbard limestone that formed during the ice age.


Immediately underneath the Marinoan deposits are some beds of rocks deposited at very regular intervals – so regular that they must have formed over thousands of years, influenced by wobbles in the Earth’s orbit. Since Svalbard was near the Equator at the time, the most likely type of wobble is caused by the Earth slowly shifting (“precessing”) its axis on cycles of approximately 20,000 years.


Researchers also found evidence of the same process in the Snowball deposits themselves. Fluctuations in ice in relation to the Earth’s orbit are a feature of our modern ice ages over the past million years, but had not been found in such an old glaciation.


For a long time the Earth was too cold for glaciers to erode and deposit sediment – the main snowball period. The sediments then show several advances and retreats of the ice. When the glaciers retreated, they left behind a patchwork of environments: shallow and deep lakes, river channels, and floodplains that appeared as arid as anything known in Earth’s history.


Carbon dioxide appears to have remained at the same high level throughout the deposition of these sediments. Since it takes millions of years for CO2 to build up in the atmosphere, this implies the sediment layers must have formed quickly – on the order of 100,000 years. All this fits with the idea of 20,000 year precession cycles.


group of climate modellers from Paris tested the theory. The rocks and the models agreed: wobbles in the Earth’s axis had caused the planet to escape its snowball phase.


So after several million years of being frozen, this icy Earth with a hot atmosphere rich in carbon dioxide had reached a Goldilocks zone – too warm to stay completely frozen, too cold to lose its ice. This transitional period lasted around 100,000 years before the glaciers fully melted and present-day Svalbard was flooded by the sea.

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First case of autoimmune encephalitis in a non-human species

First case of autoimmune encephalitis in a non-human species | Amazing Science | Scoop.it

Knut the polar bear may have met an early end but he wasn’t forgotten. The cute polar bear cub born at Berlin Zoo in 2006 and controversially reared by zookeepers, drowned as an adult after experiencing epileptic seizures. Now, the condition responsible for his death has been identified.


The cause of the seizures was unknown since no bacteria, virus or parasite could be found to explain the underlying brain inflammation. The mystery was finally solved by Harald Pruess from the German Centre for Neurodegenerative Diseases in Berlin and his team, who normally study dementia in people.


They analysed samples of Knut’s cerebrospinal fluid, which bathes the brain and spinal cord, and found high levels of an antibody known to attack a glutamate receptor in the brain. In humans, this is a sign of a disease called autoimmune encephalitis. Knut’s case is the first ever reported in a non-human.

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97% of expert papers support human-caused global warming, 3% contrarian papers have flaws, study finds

97% of expert papers support human-caused global warming, 3% contrarian papers have flaws, study finds | Amazing Science | Scoop.it

Those who reject the 97% expert consensus on human-caused global warmingoften invoke Galileo as an example of when the scientific minority overturned the majority view. In reality, climate contrarians have almost nothing in common with Galileo, whose conclusions were based on empirical scientific evidence, supported by many scientific contemporaries, and persecuted by the religious-political establishment. Nevertheless, there’s a slim chance that the 2–3% minority is correct and the 97% climate consensus is wrong.


To evaluate that possibility, a new paper published in the journal of Theoretical and Applied Climatology examines a selection of contrarian climate science research and attempts to replicate their results. The idea is that accurate scientific research should be replicable, and through replication we can also identify any methodological flaws in that research. The study also seeks to answer the question, why do these contrarian papers come to a different conclusion than 97% of the climate science literature?


This new study was authored by Rasmus Benestad, myself (Dana Nuccitelli), Stephan Lewandowsky, Katharine Hayhoe, Hans Olav Hygen, Rob van Dorland, and John Cook. Benestad (who did the lion’s share of the work for this paper) created a tool using the R programming language to replicate the results and methods used in a number of frequently-referenced research papers that reject the expert consensus on human-caused global warming. In using this tool, we discovered some common themes among the contrarian research papers.


Cherry picking was the most common characteristic they shared. We found that many contrarian research papers omitted important contextual information or ignored key data that did not fit the research conclusions.

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MouthLab: New hand-held device that quickly picks up vital signs from patient's lips and fingertips

MouthLab: New hand-held device that quickly picks up vital signs from patient's lips and fingertips | Amazing Science | Scoop.it

Vital sign monitors in hospitals are bulky, restrictive and capture limited information. A professor-engineer at Johns Hopkins has designed a battery-powered, hand-held, 3-D printed device that acts as a “check-engine light” for people. The device uses mouthpiece and thumb pad sensors to quickly test a patient’s blood pressure, breathing, blood oxygen, heart rate and heartbeat pattern.


In a study published in the September issue of the Annals of Biomedical Engineering, the MouthLab prototype’s measurements of heart rate, blood pressure, temperature, breathing rate and blood oxygen from 52 volunteers compared well with vital signs measured by standard hospital monitors. The device also takes a basic electrocardiogram.


“We see it as a ‘check-engine’ light for humans,” says the device’s lead engineer, Gene Fridman, Ph.D., an assistant professor of biomedical engineering and of otolaryngology–head and neck surgery at Johns Hopkins. “It can be used by people without special training at home or in the field.” He expects the device may be able to detect early signs of medical emergencies, such as heart attacks, or avoid unnecessary ambulance trips and emergency room visits when a patient’s vital signs are good.


Because it monitors vital signs by mouth, future versions of the device will be able to detect chemical cues in blood, saliva and breath that act as markers for serious health conditions. “We envision the detection of a wide range of disorders,” Fridman says, “from blood glucose levels for diabetics, to kidney failure, to oral, lung and breast cancers.”


The MouthLab prototype consists of a small, flexible mouthpiece like those that scuba divers use, connected to a hand-held unit about the size of a telephone receiver. The mouthpiece holds a temperature sensor and a blood volume sensor. The thumb pad on the hand-held unit has a miniaturized pulse oximeter — a smaller version of the finger-gripping device used in hospitals, which uses beams of light to measure blood oxygen levels. Other sensors measure breathing from the nose and mouth.


MouthLab also has three electrodes for ECGs — one on the thumb pad, one on the upper lip of the mouthpiece and one on the lower lip — that work about as well as the chest and ankle electrodes used on basic ECG equipment in many ambulances or clinics. That ECG signal is the basis for MouthLab’s novel way of recording blood pressure. When the signal shows the heart is contracting, the device optically measures changes in the volume of blood reaching the thumb and upper lip. Unique software converts the blood flow data into systolic and diastolic pressure readings. The study found that MouthLab blood pressure readings effectively match those taken with standard, arm-squeezing cuffs.


The hand unit relays data by Wi-Fi to a nearby laptop or smart device, where graphs display real-time results. The next generation of the device will display its own data readouts with no need for a laptop, says Fridman. Ultimately, he explains, patients will be able to send results to their doctors via cellphone, and an app will let physicians add them to patients’ electronic medical records.


A 3-D printer made the parts for the prototype, “which looks a lot like a hand-held taser,” Fridman says. “Our final version will be smaller, more ergonomic, more user-friendly and faster. Our goal is to obtain all vital signs in under 10 seconds.”

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Penn and German Researchers Help Identify Neural Basis of Multitasking

Penn and German Researchers Help Identify Neural Basis of Multitasking | Amazing Science | Scoop.it

What makes someone better at switching between different tasks? Looking for the mechanisms behind cognitive flexibility, researchers at the University of Pennsylvania and Germany’s Central Institute of Mental Health in Mannheim and Charité University Medicine Berlin have used brain scans to shed new light on this question.


By studying networks of activity in the brain’s frontal cortex, a region associated with control over thoughts and actions, the researchers have shown that the degree to which these networks reconfigure themselves while switching from task to task predicts people’s cognitive flexibility.


Experiment participants who performed best while alternating between a memory test and a control test showed the most rearrangement of connections within their frontal cortices as well as the most new connections with other areas of their brains.


A more fundamental understanding of how the brain manages multitasking could lead to better interventions for medical conditions associated with reduced executive function, such as autism, schizophrenia or dementia.


Danielle Bassett, the Skirkanich Assistant Professor of Innovation in Penn’s School of Engineering and Applied Science, is senior author on the study. Manheim’s Urs Braun and Axel Schäfer were the lead authors. The research also featured work from Andreas Meyer-Lindenberg and Heike Tost of Mannheim, Henrik Walter of Charité, and others. It was published in the Proceedings of the National Academy of Sciences.


Rather than looking at the role a single region in the brain plays, Bassett and colleagues study the interconnections between the regions as indicated by synchronized activity. Using fMRI, they can measure which parts of the brain are “talking” to one another as study participants perform various tasks. Mapping the way this activity network reconfigures itself provides a more holistic view of how the brain operates.


“We try to understand how dynamic flexibility of brain networks can predict cognitive flexibility, or the ability to switch from task to task,” Bassett said. “Rather than being driven by the activity of single brain areas, we believe executive function is a network-level process.”

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Phagraphene, a new “Relative” of Graphene Discovered

Phagraphene, a new “Relative” of Graphene Discovered | Amazing Science | Scoop.it

A group of scientists from Russia, the USA and China, led by Artyom Oganov from the Moscow Institute of Physics and Technology (MIPT), using computer generated simulation have predicted the existence of a new two-dimensional carbon material, a “patchwork” analogue of graphene called phagraphene. The results of their investigation were recently published in the journal Nano Letters.     


“Unlike graphene, a hexagonal honeycomb structure with atoms of carbon at its junctions, phagraphene consists of penta-, hexa- and heptagonal carbon rings. Its name comes from a contraction of Penta-Hexa-heptA-graphene,” says Oganov, head of the MIPT Laboratory of Computer Design.  


Two-dimensional materials, composed of a one-atom-thick layer, have attracted great attention from scientists in the last few decades.  The first of these materials, graphene, was discovered in 2004 by two MIPT graduates, Andre Geim and Konstantin Novoselov. In 2010 Geim and Novoselov were awarded the Nobel Prize in physics for that achievement.


Due to its two-dimensional structure, graphene has absolutely unique properties. Most materials can transmit electric current when unbound electrons have an energy that corresponds to the conduction band of the material. When there is a gap between the range of possible electron energies, the valence band, and the range of conductivity (the so-called forbidden zone), the material acts as an insulator. When the valence band and conduction band overlap, it acts a conductor, and electrons can move under the influence of electric field.


In graphene each carbon atom has three electrons that are bound to electrons in neighboring atoms, forming chemical bonds. The fourth electron of each atom is “delocalized” throughout the whole graphene sheet, which allows it to conduct electrical current. At the same time, the forbidden zone in the graphene has zero width. If you plot the electron energy and their location in graph form, you get a figure resembling an hour glass, i.e. two cones connected by vertices. These are known as Dirac cones.


Due to this unique condition, electrons in graphene behave very strangely: all of them have one and the same velocity (which is comparable to the velocity of light), and they possess no inertia. They appear to have no mass. And, according to the theory of relativity, particles traveling at the velocity of light must behave in this manner. The velocity of electrons in graphene is about 10 thousand kilometers a second. Electron velocities in a typical conductor vary from centimeters up to hundreds of meters per second.


Phagraphene, discovered by Oganov and his colleagues through the use of the USPEX algorithm, as well as graphene, is a material where Dirac cones appear, and electrons behave similar to particles without mass.

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Newly Discovered Prion May Cause A Neurodegenerative Disease That Is Transmissible

Newly Discovered Prion May Cause A  Neurodegenerative Disease That Is Transmissible | Amazing Science | Scoop.it

Animal experiments show how a just-discovered prion triggers a rare Parkinson’s-like disease.


Scientists claim to have discovered the first new human prion in almost 50 years. Prions are misfolded proteins that make copies of themselves by inducing others to misfold. By so doing, they multiply and cause disease. The resulting illness in this case is multiple system atrophy (MSA), a neurodegenerative disease similar to Parkinson's. The study, published August 31 in Proceedings of the National Academy of Sciences, adds weight to the idea that many neurodegenerative diseases are caused by prions.


In the 1960s researchers led by Carleton Gajdusek at the National Institutes of Health transmitted kuru, a rare neurodegenerative disease found in Papua New Guinea, and Creutzfeldt–Jakob disease (CJD), a rare human dementia, to chimpanzees by injecting samples from victims' brains directly into those of chimps. It wasn't until 1982, however, that Stanley Prusiner coined the term prion (for “proteinaceous infectious particle”) to describe the self-propagating protein responsible.


Prusiner and colleagues at the University of California, San Francisco, showed this process caused a whole class of diseases, called spongiform encephalopathies (for the spongelike appearance of affected brains), including the bovine form known as “mad cow” disease. The same protein, PrP, is also responsible for kuru, which was spread by cannibalism; variant-CJD, which over 200 people developed after eating beef infected with the bovine variety; and others. The idea that a protein could transmit disease was radical at the time but the work eventually earned Prusiner the 1997 Nobel Prize in Physiology or Medicine. He has long argued prions may underlie other neurodegenerative diseases but the idea has been slow to gain acceptance.


In 2013 a team in Prusiner's lab, including neuroscientist Kurt Giles, were trying to transmit Parkinson's disease to mice genetically engineered to produce a human protein involved in Parkinson’s, alpha-synuclein, by injecting them with brain samples from deceased patients. They failed, but for comparison they also used two MSA samples—those mice got sick. “The controls were the ones that worked,” Giles says. “So we got lots more samples.” For the new study, the team obtained 12 more MSA samples from three brain banks in London, Boston and Sydney.


The result was the same: the mice injected with these samples all developed disease within 3.5 to five months. The gene inserted in the mice has a mutation associated with a hereditary form of Parkinson's, which researchers think makes the alpha-synuclein more likely to misfold. Mice with two copies develop disease spontaneously, after about 10 months, but mice with one copy remain healthy. Injecting either type with MSA samples resulted in neurodegeneration and death for both in the same short time span.


Presumably what happens is that alpha-synuclein prions in the MSA brain samples propagate by inducing the human alpha-synuclein proteins in the mice, which are prone to misfold, to take their particular aberrant shape Afterward, these mice's brains also showed buildups of alpha-synuclein in cells, and samples from these brains also caused disease in other mice. Neither a sample from a disease-free brain nor samples from Parkinson's patients, had these effects.


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Morpho butterfly wings help break the status quo in gas sensing

Morpho butterfly wings help break the status quo in gas sensing | Amazing Science | Scoop.it

The unique properties found in the stunning iridescent wings of a tropical blue butterfly could hold the key to developing new highly selective gas detection sensors. Pioneering new research by a team of international scientists, including researchers from the University of Exeter, has replicated the surface chemistry found in the iridescent scales of the Morpho butterfly to create an innovative gas sensor.


The ground-breaking findings could help inspire new designs for sensors that could be used in a range of sectors, including medical diagnostics, industry, and the military.The research, published in the highly respected scientific journal, Nature Communications on September 1st ("Towards outperforming conventional sensor arrays with fabricated individual photonic vapour sensors inspired by Morpho butterflies"), describes how the composition of gases in different environments can be detected by measuring small colour changes of the innovative bio-inspired sensor.


Professor Pete Vukusic, one of the authors of the research and part of the Physics department at the University of Exeter said: "Bio-inspired approaches to the realisation of new technologies are tremendously valuable. In this work, by developing a detailed understanding of the subtle way in which the appearance and colour of the Morpho butterfly arises, and the way this colour depends on its local environment, our team has discovered a remarkable way in which we can advance sensor and detector technology rapidly."


Tiny tree-like nanostructures in the scales of Morpho wings are known to be responsible for the butterfly's brilliant iridescence. Previous studies have shown that vapour molecules adhere differently to the top of these structures than to the bottom due to local chemistry within the scales. This selective response to vapour molecules is the key to this bio-inspired gas sensor.

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Transparent lithium-ion battery that recharges via the sun demonstrated

Transparent lithium-ion battery that recharges via the sun demonstrated | Amazing Science | Scoop.it
A team of researchers with Kogakuin University has demonstrated a lithium ion battery which is not only nearly transparent, but can also be recharged with direct sunlight alone. The battery was demonstrated at Innovation Japan 2015, where the leader of the team, and president of the university explained the goals of their battery research and the benefits consumers might eventually see from it.


It was just four years ago that a team of researchers at Stanford unveiled a nearly transparent lithium-ion battery that was both see-through and bendable. The team in Japan has been working with the new technology since then, two years ago unveiling a nearly transparent battery of their own which was charged with a separate solar panel. Now, the team has upgraded that battery by allowing it to recharge itself when exposed to sunlight.


To make the new battery, the team tweaked the materials that were already in use—lithium iron phosphate for the positive electrode and lithium titanate and lithium hexafluorophosphate for the negative electrode—all ingredients that are already generally used to make lithium-ion batteries. When the battery is exposed to sunlight, it becomes slightly tinted (down to approximately 30 percent transmittance), lowering the amount of light that can pass through. The trick in getting them to be nearly transparent is in making them really thin—the electrodes are just 80nm and 90nm. After discharge, the team reports that light transmittance rises to approximately 60 percent. They also report output from the battery of 3.6V.


The team believes their transparent solar charged batteries could one day be used as "smart" windows for homes or offices, allowing for not only automatic tinting, but as energy capture and storage devices for use in a variety of ways. Taking the concept further, it is possible the idea could be extended at some point to consumer electronics, with displays or even entire casings made of the material to help keep phones, tablets and other gear operating when used outdoors or under other types of lighting. But first the new technology will have to be vetted to make sure it works as promised (it has been tested at 20 charge/discharges) and then to see if it can stand up to the rigors of daily use.

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For the first time, scientists "squeeze" light one particle at a time

For the first time, scientists "squeeze" light one particle at a time | Amazing Science | Scoop.it

A team of scientists has successfully measured particles of light being “squeezed”, in an experiment that had been written off in physics textbooks as impossible to observe.


Squeezing is a strange phenomenon of quantum physics. It creates a very specific form of light which is “low-noise” and is potentially useful in technology designed to pick up faint signals, such as the detection of gravitational waves.


The standard approach to squeezing light involves firing an intense laser beam at a material, usually a non-linear crystal, which produces the desired effect.


For more than 30 years, however, a theory has existed about another possible technique. This involves exciting a single atom with just a tiny amount of light. The theory states that the light scattered by this atom should, similarly, be squeezed.


Unfortunately, although the mathematical basis for this method – known as squeezing of resonance fluorescence – was drawn up in 1981, the experiment to observe it was so difficult that one established quantum physics textbook despairingly concludes: “It seems hopeless to measure it”.


So it has proven – until now. In the journal Nature, a team of physicists report that they have successfully demonstrated the squeezing of individual light particles, or photons, using an artificially constructed atom, known as a semiconductor quantum dot. Thanks to the enhanced optical properties of this system and the technique used to make the measurements, they were able to observe the light as it was scattered, and proved that it had indeed been squeezed.


Professor Mete Atature, from the Cavendish Laboratory, Department of Physics, and a Fellow of St John’s College at the University of Cambridge, led the research. He said: “It’s one of those cases of a fundamental question that theorists came up with, but which, after years of trying, people basically concluded it is impossible to see for real – if it’s there at all.”


“We managed to do it because we now have artificial atoms with optical properties that are superior to natural atoms. That meant we were able to reach the necessary conditions to observe this fundamental property of photons and prove that this odd phenomenon of squeezing really exists at the level of a single photon. It’s a very bizarre effect that goes completely against our senses and expectations about what photons should do.”

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Insecticide coating of nets proves 100% effective against mosquitoes

Insecticide coating of nets proves 100% effective against mosquitoes | Amazing Science | Scoop.it

A new method of applying insecticide to netting has proved 100% effective against some strains of mosquito, an international study reports. The electrostatic coating allows the netting to carry much higher doses of insecticide. In experiments, the coating killed off many more mosquitoes than usual.


Dutch researchers, writing in Proceedings of the National Academy of Sciences, say this could help control diseases such as malaria. Insecticide resistance in mosquitoes has become a significant problem in many parts of the world where malaria is endemic. It is thought that water-based spray insecticides and bed nets, which often contain low levels of insecticide, don't always kill the mosquitoes, allowing them to develop resistance.


In this study, researchers from the Netherlands used a charged surface, originally developed for trapping airborne pollen, and applied insecticide to it. The long-lasting electrostatic charge allowed high levels of insecticide to stick fast to the netting, giving the mosquitoes a lethal overdose when they came into contact with the surface - even for just a few seconds.


The technique was tested on different strains of mosquito in South Africa, Tanzania and at a lab at the Liverpool School of Tropical Medicine. The research team found that the electrostatic coating of insecticide killed more mosquitoes than other nettings and, for certain insecticide-resistant mosquitoes, was 100% effective. Conventional nettings kill fewer than 10% of mosquitoes, the study said.

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Artificial Leaf Harnesses Sunlight for Efficient Fuel Production

Artificial Leaf Harnesses Sunlight for Efficient Fuel Production | Amazing Science | Scoop.it

Generating and storing renewable energy, such as solar or wind power, is a key barrier to a clean-energy economy. When the Joint Center for Artificial Photosynthesis (JCAP) was established at Caltech and its partnering institutions in 2010, the U.S. Department of Energy (DOE) Energy Innovation Hub had one main goal: a cost-effective method of producing fuels using only sunlight, water, and carbon dioxide, mimicking the natural process of photosynthesis in plants and storing energy in the form of chemical fuels for use on demand. Over the past five years, researchers at JCAP have made major advances toward this goal, and they now report the development of the first complete, efficient, safe, integrated solar-driven system for splitting water to create hydrogen fuels.


"This result was a stretch project milestone for the entire five years of JCAP as a whole, and not only have we achieved this goal, we also achieved it on time and on budget," says Caltech's Nate Lewis, George L. Argyros Professor and professor of chemistry, and the JCAP scientific director.


The new solar fuel generation system, or artificial leaf, is described in the August 27 online issue of the journal Energy and Environmental Science. The work was done by researchers in the laboratories of Lewis and Harry Atwater, director of JCAP and Howard Hughes Professor of Applied Physics and Materials Science.


"This accomplishment drew on the knowledge, insights and capabilities of JCAP, which illustrates what can be achieved in a Hub-scale effort by an integrated team," Atwater says. "The device reported here grew out of a multi-year, large-scale effort to define the design and materials components needed for an integrated solar fuels generator."

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satish's curator insight, August 29, 1:24 AM

कृत्रिम पान किंवा प्रकाश संश्लेषण क्रियेसाठी सातत्याने संशोधन होत असून, त्यातील प्रत्येक यशाने आपण कृत्रिम अन्ननिर्मितीकडे जाणार आहोत. भविष्यामध्ये कदाचित आपल्याला खाद्याच्या निर्मितीसाठी वनस्पतीवरही अवलंबावे लागणार नाही, असे दिसते. सध्या या संशोधकांचे ध्येय केवळ इंधन निर्मिती इतकेच असले तरी त्यापुढेही पाहण्यास हरकत नाही.

संशोधकांना शुभेच्छा, त्यांच्या यशातच मानवाचे हित सामावलेले असणार आहे.

- सतीश कुलकर्णी

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Ocean Cleanup project completes Great Pacific Garbage Patch research expedition

Ocean Cleanup project completes Great Pacific Garbage Patch research expedition | Amazing Science | Scoop.it

In May, the Ocean Cleanup project announced that its first deployment would be delivered in the Korea Strait next year. That will pave the way for its ultimate goal of cleaning up the Great Pacific Garbage Patch. With that in mind, a research expedition at the Garbage Patch has just been completed. The concept for the Ocean Cleanup project was conceived by Dutch entrepreneur and inventor Boyan Slat and announced in 2013. Slat realized that the movement of the oceans could be harnessed in order to direct floating plastic waste into the arms of a static collection system.


After a positive feasibility study, a successful crowdfunding campaign and being named a category winner in the 2015 Designs of the Year awards, the Ocean Cleanup project recently set out to gather research in the Pacific. A fleet of 30 vessels, including a 171 ft (52 m) mothership, took part in the month-long voyage, or Mega Expedition, the primary goal of which was to determine just how much plastic is actually floating in the Great Pacific Garbage Patch.


According to the Ocean Cleanup project, this was the largest ocean research expedition in history. A series of measurement techniques were employed to sample the concentration of plastic in the area, including trawls and aerial surveys. It is also said to have been the first time that large pieces of plastic, such as ghost nets and Japanese tsunami debris, have been quantified.


Slat explains that it is not just floating bits of plastic that are a problem, but what happens to those pieces over the long term. "The vast majority of the plastic in the garbage patch is currently locked up in large pieces of debris, but UV light is breaking it down into much more dangerous microplastics, vastly increasing the amount of microplastics over the next few decades if we don’t clean it up," he says. "It really is a ticking time bomb."


The research samples collected during the expedition during have to be analyzed, but preliminary findings indicate a "higher-than-expected volume" of plastic objects found at the Pacific site.


The cleanup proper of the Great Pacific Garbage Patch is expected to begin in 2020.

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Temples hidden dangers: Incense could be more harmful than cigarette smoke, researchers find

Temples hidden dangers: Incense could be more harmful than cigarette smoke, researchers find | Amazing Science | Scoop.it

In the future, incense might need to carry a health warning, just like tobacco. That’s the conclusion of researchers who for the first time have compared the effects of burning incense indoors to inhaling tobacco smoke. Previous research has already shown how incense smoke can be harmful to a person’s health, but these new findings suggest that it’s worse than cigarettes by several measurements – a result that may alarm some in Asian countries, where incense burning is a common practice in the home and a traditional ritual in many temples.


Clearly, there needs to be greater awareness and management of the health risks associated with burning incense in indoor environments,” said Rong Zhou of the South China University of Technology, in a statement to the press.


The researchers tested two types of incense against cigarette smoke to see their effects on bacteria and the ovary cells of Chinese hamsters. Both the incense products contained the common ingredients agarwood and sandalwood, which are used in incense for their fragrances.


The findings, published in Environmental Chemistry Letters, showed that incense smoke is mutagenic, which means it can cause mutations to genetic material, primarily DNA. Compared to the cigarette smoke, the incense products were found to be more cytotoxic (toxic to cells) and genotoxic (toxic to DNA). Of the 64 compounds identified in the incense smoke, two were singled out as highly toxic.


Obviously none of this sounds very good, and for people frequently exposed to incense smoke in indoor environments, hopefully it serves as a wake-up call: mutagenics, genotoxins, and cytotoxins are all linked to the development of cancers.

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NASA: Seas around the world have risen an average of 3 inches since 1992

NASA: Seas around the world have risen an average of 3 inches since 1992 | Amazing Science | Scoop.it

Seas around the world have risen an average of nearly 3 inches since 1992, with some locations rising more than 9 inches due to natural variation, according to the latest satellite measurements from NASA and its partners. An intensive research effort now underway, aided by NASA observations and analysis, points to an unavoidable rise of several feet in the future.


Members of NASA’s new interdisciplinary Sea Level Change Team will discuss recent findings and new agency research efforts during a media teleconference today at 12:30 p.m. EDT. NASA will stream the teleconference live online.


The question scientists are grappling with is how quickly will seas rise?


“Given what we know now about how the ocean expands as it warms and how ice sheets and glaciers are adding water to the seas, it’s pretty certain we are locked into at least 3 feet of sea level rise, and probably more,” said Steve Nerem of the University of Colorado, Boulder, and lead of the Sea Level Change Team. “But we don't know whether it will happen within a century or somewhat longer.”


Team scientists will discuss a new visualization based on 23 years of sea level data – the entire record of available satellite data -- which reveals changes are anything but uniform around the globe. The record is based on data from three consecutive satellite missions, the first a collaboration between NASA and the French space agency, Centre National d'Études Spatiales, launched in 1992. The next in the series is Jason-3, led by the National Oceanic and Atmospheric Administration (NOAA) with participation by NASA, CNES and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT).

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“Spookiness” Indeed Confirmed by the First Loophole-free Quantum Test

“Spookiness” Indeed Confirmed by the First Loophole-free Quantum Test | Amazing Science | Scoop.it

Spookiness, it seems, is here to stay. Quantum theory has been put to its most stringent “loophole free” test yet, and it has come out victorious, ruling out more common sense views of reality (well, mostly). Many thanks to Matt Leifer for bringing this experiment -- by a collaboration of researchers in the Netherlands, Spain, and the UK -- to my attention (arXiv:1508.05949).

A few years ago, I wrote a feature for Scienceabout the quest to close loopholes in quantum entanglement experiments, with a number of groups around the world vying to perform the perfect test. ("Quantum Mechanics Braces for the Ultimate Test.") In that article, I quote quantum physicist and FQXi member Nicolas Gisin saying: “This race is on because the group that performs the first loophole-free test will have an experiment that stands in history.”


All prior tests have loopholes, and to get a truly definitive result, these need to be closed. One such loophole is the “detection loophole”. In many Bell tests, experimenters entangle photons and then measure their properties. The trouble is photons zip about quickly, and often simply escape from the experiment before being detected and measured. Physicists can lose as many as 80 per cent of the photons in their test. That means that experimenters have to make a ‘fair sampling’ assumption that the ones that they *do* detect are representative of the ones that have gone missing. For the conclusions to be watertight, however, you really want to keep track of all the subjects in your test.

It is easier to keep hold of entangled ions, which have been used in other experiments. The catch there, however, is that these are not often kept far enough apart to rule out the less spooky explanation that the two entangled partners simply influence each other, communicating at a speed that is less than the speed of light, during the experiment. This is known as the “communication loophole” or the “locality loophole.”

In the new paper by Henson et al, the authors describe measuring electrons with entangled spins. The entangled pairs have been separated by 1.3 km, to ensure that they do not have time to communicate (at a speed slower than the speed of light) over the course of the experiment.

They cleverly use a technique known as "entanglement swapping" to tie up both loopholes, combining the benefits of photons (which can travel long distances) with electrons (which are easier to monitor). Their electrons are placed in two different labs, 13km apart. The spin of each electron is then entangled with a photon and those two photons are fired off to a third location, where they are entangled with each other. As soon as the photons are entangled, BINGO, so too are the two original electron spins, seated in vastly distant labs. The team carried out 245 trials of the experiment, comparing entangled electrons, and report that Bell’s bound is violated.


The authors of the recent test state: ”Our experiment realizes the first Bell test that simultaneously addresses both the detection loophole and the locality loophole. Being free of the experimental loopholes, the setup can test local realist theories of nature without introducing extra assumptions such as fair-sampling, a limit on (sub-)luminal communication or the absence of memory in the setup. Our observation of a loophole-free Bell inequality violation thus rules out all local realist theories that accept that the number generators timely produce a free random bit and that the outputs are final once recorded in the electronics. This result places the strongest restrictions on local realistic theories of nature to date.”

As a test of the foundations of reality, for most physicists, these experiments dot the i’s and cross the t’s. It seemed unlikely that given the other Bell tests performed so far — even with their loopholes — that quantum theory would be found wanting, in a loophole-free test. That’s because each of the earlier experiments were so different from each other, and had different weaknesses, that nature would have to have been cunning, in quite different and particular kinds of ways in each previous experiment, to keep fooling us into thinking quantum theory was correct, if it is not. But it is important, nonetheless, to test quantum theory to its limits. After all, you never know.

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Rethinking RNA: Thousands of long noncoding RNAs are physically attached to DNA

Rethinking RNA: Thousands of long noncoding RNAs are physically attached to DNA | Amazing Science | Scoop.it

It’s a new day for RNA. In a study published in Cell Reports on Aug 18, Michael Werner, sixth-year graduate student in Cell and Molecular Biology, and Alex Ruthenburg, PhD, Neubauer Family Foundation Assistant Professor of Molecular Genetics and Cell Biology, detail their discovery of a new class of RNA molecule that could perhaps be considered the “dark matter” of the genome. They identified thousands of long noncoding RNAs that are physically attached to DNA (quite literally coating the genome), which may play important but yet unidentified roles in gene regulation.


At some point in high school and college introductory biology classes you probably learned the “Central Dogma.” It posits that in all organisms, genetic information is coded within DNA, which is converted to a ‘messenger’ molecule called RNA, which is then converted into proteins – and it is proteins that perform the various functions of the cell as molecular machines. Advances in next-generation sequencing technologies during the last decade have revealed that this is only part of the story, however.


It turns out that only ~1.5 percent of our genome contains the information to make proteins. Most of the DNA in our genome is processed into RNA ‘transcripts’ that don’t code for proteins – referred to as noncoding RNA. Some have even been shown to perform functions in the cell as RNA molecules, without the need to be turned into a protein.


Now, together with Alex Ruthenburg, Werner discovered a class of noncoding RNA that establishes a new paradigm for how RNA acts inside cells. In a recent Cell Reports paper, the two scientists show that the majority of long noncoding RNA molecules are actually associated with DNA, as opposed to messenger RNAs that are loosely dispersed throughout the nucleus.


Remarkably, they identified several thousand RNAs that are actually physically tethered to DNA and coat the human genome, which they called chromatin-enriched RNAs (cheRNAs). The discovery of these RNAs was possible through biochemical enrichment of the genome, to the exclusion of other parts of the cell that predominately contained messenger RNA. Although they didn’t intend to find these cheRNA molecules, they decided to see if there was anything else they could learn about them. To their excitement and considerable surprise, they found tantalizing hints that cheRNAs are involved in regulating the expression of nearby genes. The sheer number of these RNAs suggest that they could be a relatively common way to control genes throughout the human genome, possibly contributing to the complexity of tissues seen across our bodies.

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