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Cat parasite toxoplasma gondii uses 'Trojan horse' strategy to infect human brains and may influence human behavior

Cat parasite toxoplasma gondii uses 'Trojan horse' strategy to infect human brains and may influence human behavior | Amazing Science | Scoop.it

A food-borne parasite, Toxoplasma gondii, that infects domestic cats can get inside the human brain by commandeering special cells of the immune system which it uses as a Trojan horse to enter the central nervous system, a study has found.

 

Scientists believe they have finally discovered the mechanism that allows Toxoplasmas to pass from the human gut to the brain where it may cause behavioural changes. They have shown that the parasite can infect the dendritic white blood cells of the immune system causing them to secrete a chemical neurotransmitter that allows the infected cells, and the parasite, to cross the natural barrier protecting the brain.

 

Latest figures released in September by the Food Standards Agency show about 1,000 people a day in Britain – 350,000 a year – are being infected with toxoplasma, probably from either direct contact with cats or by eating poorly-cooked meat or vegetables. Up to 40 per cent of the British population are believed to be infected with toxoplasma and although the vast majority show no apparent symptoms, there is a risk to unborn children if their mothers become infected for the first time during pregnancy.

 

However, recent studies have also suggested that toxoplasma may be a trigger for psychological disturbances in humans, including schizophrenia, although the research has fallen well short of showing a cause-and-effect. Antonio Barragan of Sweden’s Centre for Infectious Diseases at the Karolinksa Institute in Stockholm said that when infected with toxoplasma human dendritic cells, which are not part of the central nervous system, begin to secrete a neurotransmitter called GABA which is normally produced by brain cells. “For toxoplasma to make cells in the immune defence to secrete GABA was as surprising as it was unexpected…This was unknown before. It means that the parasite had the capacity potentially to manipulate the central nervous system,” Dr Barragan said. GABA, or gamma aminobutyric acid, is involved, among other things, in inhibiting the sense of fear and anxiety. Rats and mice infected with toxoplasma show little fear of cats and Dr Barragan suggested that infected dendritic cells may continue to stimulate the production of GABA once the cells have entered the brain. However, other scientists have shown that toxoplasma is capable of producing another nerve substance called L-dopa which is a chemical precursor to the dopamine neurotransmitter, which may be another route to altering mammalian behavior. “Many neuropsychiatric disorders implicate a dysregulation of several neurotransmitters. If one is affected, this may affect the others, or the balance between neurotransmitters. How GABA specifically acts in the equation is a question for the future,” Dr Barragan said.

 

Scientists emphasised that the jury is still out on whether toxoplasma is capable of influencing the behaviour or mental state of infected people given the preliminary nature of the studies showing a tentative link between the parasite and human behaviour.

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Organic metamaterial remembers its shape and flows like a liquid

Organic metamaterial remembers its shape and flows like a liquid | Amazing Science | Scoop.it

A bit reminiscent of the Terminator T-1000, a new material created by Cornell researchers is so soft that it can flow like a liquid and then, strangely, return to its original shape. Rather than liquid metal, it is a hydrogel, a mesh of organic molecules with many small empty spaces that can absorb water like a sponge. It qualifies as a "metamaterial" with properties not found in nature and may be the first organic metamaterial with mechanical meta-properties.


Under an electron microscope the material is revealed to consist of tiny "bird's nests" of tangled DNA, top, which are tied together by more DNA stands into a mass, bottom. The tangled structure creates many tiny spaces that absorb water like a sponge. Hydrogels have already been considered for use in drug delivery -- the spaces can be filled with drugs that release slowly as the gel biodegrades -- and as frameworks for tissue rebuilding. The ability to form a gel into a desired shape further expands the possibilities. For example, a drug-infused gel could be formed to exactly fit the space inside a wound.

Dan Luo, professor of biological and environmental engineering, and colleagues describe their creation in the Dec. 2 issue of the journal Nature Nanotechnology.

 

The new hydrogel is made of synthetic DNA. In addition to being the stuff genes are made of, DNA can serve as a building block for self-assembling materials. Single strands of DNA will lock onto other single stands that have complementary coding, like tiny organic Legos. By synthesizing DNA with carefully arranged complementary sections Luo's research team previously created short stands that link into shapes such as crosses or Y's, which in turn join at the ends to form meshlike structures to form the first successful all-DNA hydrogel. Trying a new approach, they mixed synthetic DNA with enzymes that cause DNA to self-replicate and to extend itself into long chains, to make a hydrogel without DNA linkages.

 

"During this process they entangle, and the entanglement produces a 3-D network," Luo explained. But the result was not what they expected: The hydrogel they made flows like a liquid, but when placed in water returns to the shape of the container in which it was formed. Exactly how this works is "still being investigated," the researchers said, but they theorize that the elastic forces holding the shape are so weak that a combination of surface tension and gravity overcomes them; the gel just sags into a loose blob. But when it is immersed in water, surface tension is nearly zero -- there's water inside and out -- and buoyancy cancels gravity.

 

To demonstrate the effect, the researchers created hydrogels in molds shaped like the letters D, N and A. Poured out of the molds, the gels became amorphous liquids, but in water they morphed back into the letters. As a possible application, the team created a water-actuated switch. They made a short cylindrical gel infused with metal particles placed in an insulated tube between two electrical contacts. In liquid form the gel reaches both ends of the tube and forms a circuit. When water is added. the gel reverts to its shorter form that will not reach both ends. (The experiment is done with distilled water that does not conduct electricity.)

 

The DNA used in this work has a random sequence, and only occasional cross-linking was observed, Luo said. By designing the DNA to link in particular ways he hopes to be able to tune the properties of the new hydrogel.

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Surgeons implant first brain ‘pacemaker’ for Alzheimer’s disease in US

Surgeons implant first brain ‘pacemaker’ for Alzheimer’s disease in US | Amazing Science | Scoop.it
Researchers at Johns Hopkins Medicine have surgically implanted a pacemaker-like device into the brain of a patient in the early stages of Alzheimer’s disease, the first such operation in the United States.

The device, which provides deep brain stimulation and has been used in thousands of people with Parkinson’s disease, is seen as a possible means of boosting memory and reversing cognitive decline. Instead of focusing on drug treatments, many of which have failed in recent clinical trials, the research focuses on the use of the low-voltage electrical charges delivered directly to the brain. There is no cure for Alzheimer’s disease yet.

 

The surgery is part of a federally funded, multicenter clinical trial marking a new direction in clinical research designed to slow or halt the ravages of the disease, which slowly robs its mostly elderly victims of a lifetime of memories and the ability to perform the simplest of daily tasks, researchers at Johns Hopkins say. Some 40 patients are expected to receive the deep brain stimulation implant over the next year or so at Johns Hopkins and four other institutions in North America as part of the Advance Study led by Constantine G. Lyketsos, M.D., M.H.S., a professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine, and Andres Lozano, M.D., Ph.D., chairman of the neurology department at the University of Toronto. Only patients whose cognitive impairment is mild enough that they can decide on their own to participate will be included in the trial. Other sites performing the operation, supported by the National Institutes of Health’s National Institute on Aging (R01AG042165), are the University of Toronto, the University of Pennsylvania, the University of Florida, and Banner Health System in Phoenix, Ariz. The medical device company, Functional Neuromodulation Ltd., is also supporting the trial.

 

While experimental for Alzheimer’s patients, more than 80,000 people with the neurodegenerative disorder Parkinson’s disease have undergone the procedure over the past 15 years, with many reporting fewer tremors and requiring lower doses of medication afterward, Lyketsos says. Other researchers are testing deep brain stimulation to control depression and obsessive-compulsive disorder resistant to other therapies. The surgery involves drilling holes into the skull to implant wires into the fornix on either side of the brain. The fornix is a brain pathway instrumental in bringing information to the hippocampus, the portion of the brain where learning begins and memories are made, and where the earliest symptoms of Alzheimer’s appear to arise. The wires are attached to a pacemaker-like device, the “stimulator,” which generates tiny electrical impulses into the brain 130 times a second. The patients don’t feel the current, Rosenberg says. “Deep brain stimulation might prove to be a useful mechanism for treating Alzheimer’s disease, or it might help us develop less invasive treatments based on the same mechanism,” Rosenberg says. By 2050, the number of people age 65 and older with Alzheimer’s disease may triple, experts say, from 5.2 million to a projected 11 million to 16 million, unless effective treatments are found.

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Intelligent Frames for Psychology / Neuroscience (continuously updated)

Intelligent Frames for Psychology / Neuroscience (continuously updated) | Amazing Science | Scoop.it
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Catfish strand themselves to catch and eat pigeons

Catfish strand themselves to catch and eat pigeons | Amazing Science | Scoop.it

In Southwestern France, a group of fish have learned how to kill birds. As the River Tarn winds through the city of Albi, it contains a small gravel island where pigeons gather to clean and bathe. And patrolling the island are European catfish—1 to 1.5 metres long, and the largest freshwater fish on the continent. These particular catfish have taken to lunging out of the water, grabbing a pigeon, and then wriggling back into the water to swallow their prey. In the process, they temporarily strand themselves on land for a few seconds.

 

Other aquatic hunters strand themselves in a similar way, including bottlenose dolphins from South Carolina, which drive small fish onto beaches, and Argentinian killer whales, which swim onto beaches to snag resting sealions. The behaviour of the Tarn catfishes is so similar that Julien Cucherousset from Paul Sabatier University in Toulouse describes them as “freshwater killer whales”.

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mdashf's curator insight, December 13, 2012 10:26 AM

Bastards !! LOL

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Brain 'reading centers' are culturally universal

Brain 'reading centers' are culturally universal | Amazing Science | Scoop.it

Learning to read Chinese might seem daunting to Westerners used to an alphabetic script, but brain scans of French and Chinese native speakers show that people harness the same brain centers for reading across cultures.


Via Sakis Koukouvis
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Most of the harmful mutations in humans arose in the past 5,000 to 10,000 years

Most of the harmful mutations in humans arose in the past 5,000 to 10,000 years | Amazing Science | Scoop.it

European Americans have a larger proportion of potentially harmful variants than African Americans --- probably an artefact of their original migration out of Africa.

 

The human genome has been busy over the past 5,000 years. Human populations have grown exponentially, and new genetic mutations arise with each generation. Humans now have a vast abundance of rare genetic variants in the protein-encoding sections of the genome.

 

A study published in Nature now helps to clarify when many of those rare variants arose. Researchers used deep sequencing to locate and date more than one million single-nucleotide variants — locations where a single letter of the DNA sequence is different from other individuals — in the genomes of 6,500 African and European Americans.

 

The findings confirm their earlier work suggesting that the majority of variants, including potentially harmful ones, were picked up during the past 5,000–-10,000 years.

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Whitney Souery's curator insight, August 29, 2013 9:49 AM

Genetic mutations (both negative and positive included) arose during migration. This article descirbes how European Americans have a greater amount of mutations than African Americans- meaning that after the migration from Africa, mutations began to arise. 

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New, Faster Way To Make Vaccines Using mRNA

New, Faster Way To Make Vaccines Using mRNA | Amazing Science | Scoop.it

Researchers in Germany have found a new way to make a flu vaccine. Their approach, shown to protect mice against the virus, utilizes messenger RNA instead of purified protein to generate the immune response. If it proves effective in humans it could decrease the cost of making vaccines, and cut production time by two-thirds.

 

Culturing the viruses in this way is costly and labor-intensive. Generating the large amounts of viruses used for vaccines each year takes a good six months. And results will vary, owing to the fact that different viruses will grow better or worse in the culture preparations.

 

Scientists at the Friedrich-Loeffler-Institute and biotech company CureVac have taken advantage of the body’s own machinery in an attempt to shortcut the vaccine production process. Rather than growing up viruses and purifying their proteins, their ‘vaccines’ contain pieces of synthetic messenger RNA (mRNA) which encoded the viral surface proteins, in this case from the H1N1 strain. mRNA is the single-stranded molecule which carries the copy of a protein sequence found in DNA. It’s shuttled outside the cell’s nucleus to the cytoplasm where it is read and directs the binding of amino acids into a protein. Injecting the mRNA beneath the skin of mice caused the animals’ own cells to generate the viral proteins. After being given just two injections adult mice were protected from illness due to influenza for the rest of their lives. The injections, however, still offered protection but weren’t as effective when given to very young or “elderly” mice.

 

The vaccine was also tested on pigs and ferrets. The immunity of these animals wasn’t assessed directly by challenging them with influenza but, up to 8 weeks after injection, their blood sera showed antibodies and other indicators of immunity against the flu virus. The immune response from both animals was in fact sufficient to meet the requirements set by the European Medicines Agency for vaccine development.

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Search For Extraterrestrial Life Suggests Other Solar Systems More Habitable Than Ours

Search For Extraterrestrial Life Suggests Other Solar Systems More Habitable Than Ours | Amazing Science | Scoop.it

Scattered around the Milky Way are stars that resemble our own sun—but a new study is finding that any planets orbiting those stars may very well be hotter and more dynamic than Earth. That’s because the interiors of any terrestrial planets in these systems are likely warmer than Earth—up to 25 percent warmer, which would make them more geologically active and more likely to retain enough liquid water to support life, at least in its microbial form.

 

The preliminary finding comes from geologists and astronomers at Ohio State University who have teamed up to search for alien life in a new way. They studied eight “solar twins” of our sun—stars that very closely match the sun in size, age, and overall composition—in order to measure the amounts of radioactive elements they contain. Those stars came from a dataset recorded by the High Accuracy Radial Velocity Planet Searcher spectrometer at the European Southern Observatory in Chile.

 

They searched the solar twins for elements such as thorium and uranium, which are essential to Earth’s plate tectonics because they warm our planet’s interior. Plate tectonics helps maintain water on the surface of the Earth, so the existence of plate tectonics is sometimes taken as an indicator of a planet’s hospitality to life.

 

Of the eight solar twins they’ve studied so far, seven appear to contain much more thorium than our sun—which suggests that any planets orbiting those stars probably contain more thorium, too. That, in turn, means that the interior of the planets are probably warmer than ours.

 

For example, one star in the survey contains 2.5 times more thorium than our sun, said Ohio State doctoral student Cayman Unterborn. According to his measurements, terrestrial planets that formed around that star probably generate 25 percent more internal heat than Earth does, allowing for plate tectonics to persist longer through a planet’s history, giving more time for live to arise. “If it turns out that these planets are warmer than we previously thought, then we can effectively increase the size of the habitable zone around these stars by pushing the habitable zone farther from the host star, and consider more of those planets hospitable to microbial life,” said Unterborn.

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mdashf's curator insight, December 13, 2012 10:28 AM

Another proof of the contingent creation of life

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New Evidence of Human Influence on Global Warming - Troposphere warms and stratosphere cools

New Evidence of Human Influence on Global Warming - Troposphere warms and stratosphere cools | Amazing Science | Scoop.it
Using state-of-the-art climate models, a new study has found clear evidence of a discernible human influence on atmospheric temperature.

 

Specifically, Ben Santer of Lawrence Livermore National Laboratory and 21 colleagues found that while the troposphere — the lowest part of the atmosphere — has warmed over the past three decades, the stratosphere, which starts 5 to 12 miles above the ground, has cooled. This is exactly what you’d expect if greenhouse gases were trapping heat near the surface rather than letting it percolate upward. “This is not a new idea,” Santer said in an interview. “We did the first fingerprinting studies of the troposphere and stratosphere back in 1996.”

 

The problem back then, Santer said, was that only a couple of climate models were available for studies like this. Models are crucial in this kind of research because you can’t do controlled experiments with the planet the way doctors do when they test new pharmaceuticals. With medicines, you give some patients the drug and others a placebo, or sugar pill, and see the difference in how their illnesses respond.

 

With the climate system, by contrast, there’s only one patient, and it’s already been dosed with extra greenhouse gases such as carbon dioxide. So scientists like Santer do simulations of how the atmosphere should look both with and without those extra gases. Unlike in 1996, Santer and his co-authors had 20 different simulations to work with for this study, all of them state-of-the-art models developed for the upcoming major report of the Intergovernmental Panel on Climate Change, due out starting in 2014.

 

The obtained results mean, that the warming of the troposphere and cooling of the stratosphere can’t be explained in any other way than by the heat-trapping effects of human-generated greenhouse gases. “It was surprising to me how large the signal was,” Santer said

This is only one of the fingerprints scientists expect to see in a human–influenced climate, moreover. “In the past we’ve looked at ocean surface temperatures changes in hurricane-forming regions, patterns in atmospheric pressure; rainfall patterns, and changes in Arctic sea ice,” Santer said. All of these and more can be identified more easily and clearly with the new models. “I think these simulations are like a scientific gold mine,” Santer said. “Analysts will be exploiting them for many years to come.”

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Organisms put to a test: Earth’s toughest life forms could survive on Mars

Organisms put to a test: Earth’s toughest life forms could survive on Mars | Amazing Science | Scoop.it

The surface of Mars is a tough place to survive, but researchers at the German Aerospace Center (DLR) found some lichens and cyanobacteria tough enough to handle those conditions.

 

How tough is it on Mars? Pretty tough. First, the Martian surface pressure of 6 millibars is pretty much a vacuum compared to Earth’s surface pressure of 1000. 6 millibars of pressure corresponds to a point waaay up in Earth’s middle stratosphere about 35 kilometers above the surface. This is an altitude almost 5 times taller than Mount Everest and right about where altitude records for air-breathing jet airplanes are set. Next, you’ve got the harsh radiation from the Sun. On gentle Earth, much of the dangerous photon radiation from the sun is filtered out by Earth’s thick atmosphere. But on atmospherically-challenged Mars, energetic ultraviolet rays blast the surface. These rays could plow through an unprotected biological cell and wreak havoc on the critical information-carrying genetic material in the cell. If that weren’t bad enough, the rays can also smack consitutents of the martian rocks and dirt and make some really nasty reactive chemical species that could chew up any cellular biological membranes not tough enough to resist. Finally, Mars is very dry and cold, dryer than the driest deserts on Earth. Any water might come in a brief morning dew that quickly evaporates as the temperature rapidly fluctuates. Life would have to struggle getting water quickly during these transient events then survive being freeze-dried for long periods of time.

 

To see if they could find terrestrial life tough enough for Mars, the researchers collected specimens of organisms that were found in some of the most extreme and inhospitable places on Earth. They collected organisms from inside rocks, on mountain tops, and in the polar regions. These are places that might come closest to the environment on Mars. The researchers then created an environmental chamber that simulated conditions on Mars: ultraviolet radiation, infrared radiation, martian soil, low pressure, atmospheric mix, temperature ranging from -50 C to 23 C, the whole bit. They threw the collected specimens in the chamber to see if any could survive. After a little over a month had passed, the researchers found that some lichen and cyanobacteria were still alive. Most surprisingly, the lichen and cyanobacteria didn’t just sit dormant, huddled down waiting for someone to open up the chamber and let them out; they were active. They sat in the martian chamber and took in simulated martian sunlight and made molecules and did all the things a living, functioning, active organism should do – they were happy!

 

Cyanobacteria are very important to the story of life on Earth. Cyanobacteria used to be called blue-green algae, but they are bacteria, not algae. While algae have a nucleus that has the information-carrying genetic material, cyanobacteria do not. Cyanobacteria have the genetic material distributed all over the inside of the cell, rather than specialized compartments. Cyanobacteria use molecules like chlorophyll, phycoerythrin, and phycocyanin to harvest light energy. It is the phycocyanin that gives the cyanobacteria the characteristic blue-green color. The light-harvesting compartments in algae and plant cells, called chloroplasts, may have originally started out as cyanobacteria that got incorporated inside the algae or plant cells. Cyanobacteria are special in that they can live in high-oxygen or low-oxygen environments. Importantly for us oxygen-breathing types, cyanobacteria may have been responsible for generating much of the oxygen in Earth’s early atmosphere. Fossil structures of cyanobacteria have been found that are over 2.8 billion years old. Cyanobacteria are primordial, and they changed our planet.

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First-ever hyperspectral images of Earth's auroras

First-ever hyperspectral images of Earth's auroras | Amazing Science | Scoop.it
Hoping to expand our understanding of auroras and other fleeting atmospheric events, a team of space-weather researchers designed and built NORUSCA II, a new camera with unprecedented capabilities that can simultaneously image multiple spectral bands, in essence different wavelengths or colors, of light. The camera was tested at the Kjell Henriksen Observatory (KHO) in Svalbard, Norway, where it produced the first-ever hyperspectral images of auroras—commonly referred to as "the Northern (or Southern) Lights"—and may already have revealed a previously unknown atmospheric phenomenon.

Via Sakis Koukouvis
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SESAME - Inside the world's most "impossible" science project

SESAME - Inside the world's most "impossible" science project | Amazing Science | Scoop.it

Against expectation, Israel, Iran and the Arab world are collaborating on a major new science project in the Middle East. Reporting assignments in the Middle East often involve great danger - think of Syria and Gaza. Others run into bureaucratic obstruction. But the SESAME science project in Jordan is so bizarre it presented challenges of a wholly unexpected kind. The first was the sheer difficulty of grasping that the story was not the figment of someone's imagination but was actually happening.

 

A "synchrotron" facility called SESAME - at its heart, a particle accelerator not unlike Europe's CERN - is coming together in Jordan. A news story on the SESAME project explains the science it aims to do, but that is not the striking thing about it. On the scale of surprises that take a very long while to sink in, SESAME is off the scale: common sense would scream at you that it just should not be feasible.

 

The scenario goes as follows: take one of the world's most unstable regions, pick some of the countries that are most violently opposed to each other and then bring them together under one roof to do science. An extraordinarily bold idea to plant a world-class science facility - a synchrotron light source - in the heart of the Middle East for researchers from anywhere from Cairo to Tel Aviv to Tehran”. The list of countries involved looks utterly improbable: it includes Jordan, Turkey, Bahrain and Egypt - so far so normal. But then add Iran and - amazingly - Israel too.

 

And they actually have to meet each other every year to discuss plans including the fraught question of contributions. This is SESAME in a nutshell: an extraordinarily bold idea to plant a world-class science facility - a synchrotron light source - in the heart of the Middle East for researchers from anywhere from Cairo to Tel Aviv to Tehran.

 

So the first obstacle is getting past one's own natural incredulity that anything like this could ever get off the ground. But the fact is that it has. SESAME not only has a rather grand new building, near the village of Allan in the hills northwest of Amman; it also has the first components that will generate and accelerate a flow of electrons. If all goes well, sometime around 2015, the energy from those electrons will be harnessed to help peer into the world of the microscopically small. This is no ordinary science project. Yet somehow, after a decade of huge uncertainties about funding and endless doubts about who will take part, the people making this project work have found a way of rubbing along.

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Flexible Silicon Solar-Cell Fabrics Soon? Wear a solar fiber jacket

Flexible Silicon Solar-Cell Fabrics Soon? Wear a solar fiber jacket | Amazing Science | Scoop.it

The first flexible, fiber-optic solar cell that can be woven into clothes. An international team of engineers, physicists, and chemists have created the first fiber-optic solar cell. These fibers are thinner than human hair, flexible, and yet they produce electricity, just like a normal solar cell. 

 

The research opens the door to the possibility of weaving together solar-cell silicon wires to create flexible, curved or twisted solar fabrics. The findings by an international team of chemists, physicists and engineers, led by John Badding, a professor of chemistry at Penn State, will be posted by the journal Advanced Materials in an early online edition today (Dec. 6) and will be published on a future date in the journal's print edition.

 

The team's new findings build on earlier work addressing the challenge of merging optical fibers with electronic chips -- silicon-based integrated circuits that serve as the building blocks for most semiconductor electronic devices such as solar cells, computers and cellphones. Rather than merge a flat chip with a round optical fiber, the team found a way to build a new kind of optical fiber -- which is thinner than the width of a human hair -- with its own integrated electronic component, thereby bypassing the need to integrate fiber-optics with chips. To do this, they used high-pressure chemistry techniques to deposit semiconducting materials directly, layer by layer, into tiny holes in optical fibers.

 

Now, in their new research, the team members have used the same high-pressure chemistry techniques to make a fiber out of crystalline silicon semiconductor materials that can function as a solar cell -- a photovoltaic device that can generate electrical power by converting solar radiation into direct-current electricity. "Our goal is to extend high-performance electronic and solar-cell function to longer lengths and to more flexible forms. We already have made meters-long fibers but, in principle, our team's new method could be used to create bendable silicon solar-cell fibers of over 10 meters in length," Badding said. "Long, fiber-based solar cells give us the potential to do something we couldn't really do before: We can take the silicon fibers and weave them together into a fabric with a wide range of applications such as power generation, battery charging, chemical sensing and biomedical devices."

 

Badding explained that one of the major limitations of portable electronics such as smartphones and iPads is short battery life. Solar-boosted batteries could help solve this problem. "A solar cell is usually made from a glass or plastic substrate onto which hydrogenated amorphous silicon has been grown," Badding explained. "Such a solar cell is created using an expensive piece of equipment called a PECVD (plasma-enhanced chemical vapor deposition) reactor and the end result is something flat with little flexibility. But woven, fiber-based solar cells would be lightweight, flexible configurations that are portable, foldable and even wearable." This material could then be connected to electronic devices to power them and charge their batteries. "The military especially is interested in designing wearable power sources for soldiers in the field," Badding added.

 

The team members believe that another advantage of flexibility in solar-cell materials is the possibility of collecting light energy at various angles. "A typical solar cell has only one flat surface," Badding said. "But a flexible, curved solar-cell fabric would not be as dependent upon where the light is coming from or where the sun is in the horizon and the time of day." 

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Could synthetic fuels eliminate entire US need for crude oil, create ‘new economy’?

Could synthetic fuels eliminate entire US need for crude oil, create ‘new economy’? | Amazing Science | Scoop.it

The U.S. could eliminate the need for crude oil by using a combination of coal, natural gas, and non-food crops to make synthetic fuel, a team of Princeton researchers has found. Besides economic and national security benefits, the plan has potential environmental advantages. Because plants absorb carbon dioxide to grow, the United States could cut vehicle greenhouse emissions by as much as 50 percent in the next several decades using non-food crops to create liquid fuels, the researchers said.

 

Synthetic fuels would be an easy fit for the transportation system because they could be used directly in automobile engines and are almost identical to fuels refined from crude oil. That sets them apart from currently available biofuels, such as ethanol, which have to be mixed with gas or require special engines.

 

In a series of scholarly articles over the past year, a team led by Christodoulos Floudas, a professor of chemical and biological engineering at Princeton, evaluated scenarios in which the U.S. could power its vehicles with synthetic fuels rather than relying on oil. Floudas’ team also analyzed the impact that synthetic fuel plants were likely to have on local areas and identified locations that would not overtax regional electric grids or water supplies.

 

“The goal is to produce sufficient fuel and also to cut CO2 emissions, or the equivalent, by 50 percent,” said Floudas, the Stephen C. Macaleer ’63 Professor in Engineering and Applied Science. “The question was not only can it be done, but also can it be done in an economically attractive way. The answer is affirmative in both cases.”

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Super-massive black hole with a mass half the size of its hosting galaxy

Super-massive black hole with a mass half the size of its hosting galaxy | Amazing Science | Scoop.it

A new survey recently reported in Nature found a supermassive black hole (mass~17 billions of solar masses) at the center of a relatively "light" galaxy. This wouldn't be a surprise if the mass of the black hole wasn't more than half the mass of the buldge of the hosting galaxy. The black line shows the mass–luminosity relation for galaxies with a directly measured black-hole mass.

 

NGC 1277 is a significant positive outlier. Indeed, we already know that most galaxies -- including our own Milky Way -- host supermassive black holes which lurk at the galactic center. Also, the mass of the black hole is believed to be tightly connected with the properties of the hosting galaxy. Several models of galaxy dynamics and mergers predict a black hole mass VS bulge luminosity relation similar to that shown in the Figure above and this has important implications in the understanding of the galaxy evolution and of black hole population models. Typically, the mass of the black hole is about 0.1 per cent of the mass of the stellar bulge of the galaxy and the maximum mass fraction observed so far was about 10%.

 

The discovery of NGC 1277, a compact, lenticular galaxy with a mass of roughly 1.2x10^11 solar masses, is particularly interesting because this galaxy hosts a black hole of mass about 1.7x10^10 solar masses, that is, roughly 59% of the total bulge mass. Indeed, it's evident in the Figure above how NGC 1277 deviates from the expected empirical behavior.

 

This discovery seems confirmed by other observations of galaxies that host oversized black holes and it might suggest a failure (or the need of some improvement) in current models.

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Screen-On-A-Lens: A Liquid Crystal-based Contact Lens Display

Switching of a contact lens shaped display. The contact lens is still transparent but is able to modulate the transmitted light using LCD technology. Direct applications could be medical, as an artificial iris, or cosmetic, as an iris with tunable color, or it just could serve as a gimmick. The dollar sign is a reference to the many cartoons featuring people/figures with dollars in their eyes!

 

When worn, the image would only be visible to bystanders, since the eye cannot focus on objects in such a close proximity. Research is currently being performed to solve the focusing problem and to see whether an embedded contact lens display that can be seen by the lens wearer is feasible.

 

All work was performed in the Centre for Microsystems Technology, Ghent University, Belgium.

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A step toward creating a bio-robot hybrid

A step toward creating a bio-robot hybrid | Amazing Science | Scoop.it

Would it be possible to integrate biological components with advanced robotics, using biological cells to do machine-like functions and interface with an electronic nervous system — in effect, creating an autonomous, multi-cellular biohybrid robot? Researchers Orr Yarkoni, Lynn Donlon, and Daniel Frankel, from the Department of Chemical Engineering at Newcastle University think so, and they’ve developed an interface to allow communication between the biological and electronic components. One of the major challenges in developing biohybrid devices is in the interface between biological and electronic components. Most cellular signals are simply not compatible with electronics.

 

However, manipulation of signal transduction pathways is one way to interface cells with electronics. So the researchers genetically engineered protein cells from a Chinese hamster ovary to produce nitric oxide (NO) in response to visible light. Here’s how:

 

1. They genetically engineered the nitric oxide synthase protein eNOS by inserting a light-oxygen-voltage (LOV) domain into the gene. This created a photoactive version of the eNOS protein that could produce NO in response to excitation by visible light.

 

2. They attached these mutant cells to a nickel tetrasulfonated
phthalocyanine (NiTSPc)-modified platinum electrode that detected the NO and converted it into an electrical signal.

 

In summary: The researchers converted an optical signal into a chemical signal (NO), and converted the chemical signal into an electrical signal. This signal could, in turn, be used to control a robot. Unlike solid-state photodetectors, the cells have the ability to self-reproduce and the potential to combine input signals to perform computation. With rapid advances in synthetic biology, manipulation of metabolic pathways to integrate with machinery will some day allow the development of advanced robotics, the researchers suggest.

 


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A roadmap for metabolic reprogramming of aging

A roadmap for metabolic reprogramming of aging | Amazing Science | Scoop.it

To survey previously uncharted territory, a team of researchers at UW-Madison has created an “atlas” that maps more than 1,500 unique landmarks within mitochondria that could provide clues to the metabolic connections between caloric restriction and aging.

 

The map, as well as the techniques used to create it, could lead to a better understanding of how cell metabolism is rewired in some cancers, age-related diseases and metabolic conditions such as diabetes.


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Telepresence: Robots Invade Hospitals – “Doctors Can Be Anywhere, Anytime”

Telepresence: Robots Invade Hospitals –  “Doctors Can Be Anywhere, Anytime” | Amazing Science | Scoop.it

A disembodied human face hangs atop a robot chassis next to a Redmond, Oregon hospital bed (not pictured). The doctor on the screen is 20 miles distant, in Bend. But from there he is able to assess the patient and determine whether she should be moved to a better equipped hospital in Bend or further afield.

 

The doctor’s name is Dr. Kevin Sherer, the volunteer patient Anita Boucher, and together they recently performed a test run using an InTouch Health RP-7i telepresence robot nicknamed Roda (robotic office diagnostic assistant).

 

Dr. Sherer can pilot Roda down the hall with a joystick, turn its camera to check vitals, and interact with the patient by way of the screen atop Roda’s chassis. In addition to telepresence capabilities—and with the help of a nurse placing a special stethoscope—he can remotely check the patient’s heart beat over headphones.

 

Although they haven’t had a chance to make full use of Roda’s capability, Daniel Davis of St. Charles Redmond told Singularity Hub most medical equipment with USB connectivity can be transmitted to doctors. And according to Davis, those early tests using volunteer mock patients went well, winning over even the skeptics. Since then, the robot has been put to good use, including at least one midnight visit.

 

http://tinyurl.com/awma5qa


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"World's smallest wrench" is able to rotate individual cells

"World's smallest wrench" is able to rotate individual cells | Amazing Science | Scoop.it

A team from the University of Texas at Arlington, led by assistant professor Samarendra Mohanty, created the device.

 

The business end of the fiber-optic spanner consists of two optical fibers, which are situated end-to-end with a small gap between them. A beam of laser light is emitted from each of these fibers – when the two beams are lined up, the force of the streaming photons is sufficient to trap a microscopic object such as a cell between them. If the fibers are slightly offset, however, and their beams hit that cell on either side, they can actually spin it around in place.

 

By changing the orientation of the fibers, the cell can be turned on any axis. It’s similar to the technology used in “optical tweezers,” although those are used more just for pushing or holding microscopic objects, not for rotating them.

 

Along with its use for examining cells, the researchers believe that the fiber-optic spanner could also be used for applications such as untwisting DNA strands, guiding neurons within the spinal cord, or mixing fluids in lab-on-a-chip devices.


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mdashf's curator insight, December 13, 2012 10:40 AM

the wrench .. hmm its called a wrenchie in Odia (obviously a borrowed word from English) there is a formula why ie is used for ee, ii, i, and y or yi etc

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Eurasian Jays are not only aware that others may be watching, but also might be surreptitiously listening, too

Eurasian Jays are not only aware that others may be watching, but also might be surreptitiously listening, too | Amazing Science | Scoop.it

Hide some gold coins in your backyard, and you'll probably check around to make sure no one is spying on where you stash them. Eurasian jays are no different. A new study finds that the pinkish-gray birds with striking blue wing patches are not only aware that others may be watching while they stash their nuts and seeds for the winter, but also might be surreptitiously listening, too. In response, they change their behaviors—stashing nuts in quieter places, for example. The findings suggest that the jays may be able to understand another's point of view, an ability rarely seen in animals other than humans.

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Smartphones might soon develop emotional intelligence

Smartphones might soon develop emotional intelligence | Amazing Science | Scoop.it
If you think having your phone identify the nearest bus stop is cool, wait until it identifies your mood.

 

New research by a team of engineers at the University of Rochester may soon make that possible. At the IEEE Workshop on Spoken Language Technology on Dec. 5, 2012, the researchers will describe a new computer program that gauges human feelings through speech, with substantially greater accuracy than existing approaches. Surprisingly, the program doesn't look at the meaning of the words. "We actually used recordings of actors reading out the date of the month—it really doesn't matter what they say, it's how they're saying it that we're interested in," says Wendi Heinzelman, professor of electrical and computer engineering.

 

Heinzelman explained that the program analyzes 12 features of speech, such as pitch and volume, to identify one of six emotions from a sound recording. And it achieves 81% accuracy— a significant improvement on earlier studies that achieved only about 55% accuracy.

 

The research has already been used to develop a prototype of an app. The app displays either a happy or sad face after it records and analyzes the user's voice. It was built by one of Heinzelman's graduate students, Na Yang, during a summer internship at Microsoft Research. "The research is still in its early days," Heinzelman adds, "but it is easy to envision a more complex app that could use this technology for everything from adjusting the colors displayed on your mobile to playing music fitting to how you're feeling after recording your voice."

 

Heinzelman and her team are collaborating with Rochester psychologists Melissa Sturge-Apple and Patrick Davies, who are currently studying the interactions between teenagers and their parents. "A reliable way of categorizing emotions could be very useful in our research," says Sturge-Apple. "It would mean that a researcher doesn't have to listen to the conversations and manually input the emotion of different people at different stages."

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New contender for oldest dinosaur

New contender for oldest dinosaur | Amazing Science | Scoop.it
Palaeontologists identify what is likely to be the oldest known dinosaur specimen, patching a 10-15-million-year hole in dinosaurs' evolutionary history.

 

It walked on two legs, measured 2-3m in length with a large tail and weighed between 20 and 60kg. The find suggests that many millions of years passed between dinosaurs' first members and their dominance on land.

 

"It fills a gap between what we previously knew to be the oldest dinosaurs and their other closest relatives," report co-author Paul Barrett, of the Natural History Museum in London, told BBC News. The find shores up the idea that dinosaurs evolved on the southern parts of the supercontinent Pangaea. "There was this big gap in the fossil record where dinosaurs should've been present and this fossil neatly fills that gap." The early evolution of dinosaurs is difficult to unpick, as a rich variety of reptiles were proliferating at the time - and some may even have independently evolved characteristics that are associated with dinosaurs.

 

It now appears that those creatures shared the southern part of the supercontinent Pangaea - now South America, Africa, Antarctica and Australia - with N parringtoni. "Those animals were the earliest of this group that led up toward dinosaurs," explained Dr. Barrett. "Now this takes dinosaurs back to the right kind of time when those two groups would have split apart from each other." As it closes that evolutionary gap, it shows that dinosaurs did not start out as dominant as they later became. "Dinosaurs start out as a very insignificant group of reptiles - all relatively small animals, relatively rare in comparison with other reptile groups - and it's only a bit later in their history that they suddenly explode and take over as the dominant forms of life for nearly 100 million years" - Barrett said.

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How to build a million-qubit quantum computer based on a hybrid dual-quantum dot/superconducting resonator device

How to build a million-qubit quantum computer based on a hybrid dual-quantum dot/superconducting resonator device | Amazing Science | Scoop.it

A team led by Princeton‘s Associate Professor of Physics Jason Petta has developed a new method that could eventually allow engineers to build a working quantum computer consisting of millions of quantum bits (qubits), based on a hybrid dual-quantum dot/superconducting resonator device .

 

To make the quantum dots, the team isolated a pair of electrons on a small section of material called a “semiconductor nanowire.” Basically, that means a wire that is so thin that it can hold electrons like soda bubbles in a straw. They then created small “cages” along the wire. The cages are set up so that electrons will settle into a particular cage depending on their energy level.

 

This is how the Princeton team reads the spin state: electrons of similar spin will repel, while those of different spins will attract. So the team manipulates the electrons to a certain energy level and then reads their position. If they are in the same cage, they are spinning differently; if they are in different cages, the spins are the same. The second step is to place this quantum dot inside the microwave channel, allowing the team to transfer the information about the pair’s spin state — the qubit.

 

Petta said the next step is to increase the reliability of the setup for a single electron pair. After that, the team plans to add more quantum dots to create more qubits. Team members are cautiously optimistic. There appear to be no insurmountable problems at this point but, as with any system, increasing complexity could lead to unforeseen difficulties.

 

“The methods we are using here are scalable, and we would like to use them in a larger system,” Petta said. “But to make use of the scaling, it needs to work a little better. The first step is to make better mirrors for the microwave cavity.”

 

Original article: http://tinyurl.com/9o698k9

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