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A breaktrough in flow battery technology - comagenius

A breaktrough in flow battery technology - comagenius | comagenius | Scoop.it
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Researchers have found the right organic molecule to use in low cost, metal free flow batteries which can store the energy produced by renewable sources.

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Switchable telescopic contact lens that lets you zoom in - comagenius

Switchable telescopic contact lens that lets you zoom in - comagenius | comagenius | Scoop.it
Design and first experimental demonstration for a switchable magnifying contact lens (1.17 mm thick) was recently reported in Optical Society's1 open-access journal Optics Express2. The optical system is based on a concentric multiple-reflection geometry which provide a combination of telescopic and unmagnified vision through two independent optical paths. The magnified path incorporates a telescopic arrangement to achieve 2.8x magnification on the eye, while a central path provides unmagnified vision. The team built the LCD shutter mechanism into a modified pair of 3D TV glasses, placed over the eyeball, to switch between these two paths and they claim that the LCD technology can be built into the lens easily. The current, very promissing, study is based on design in PMMA (polymethyl methacrylate), a gas-impermeable polymer commonly used for early contact lenses. Today’s contact lenses can be produced with high levels of gas permeability, and team suggests that the  future versions of their telescopic magnifying contact lenses will have to be made from rigid gas permeable polymers. Additionally, how these lenses will be switched on and off when they are built with LCD technology has yet to be revealed.
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Secrets behind Vitamin C… Is it really good or bad for our health? - comagenius

Secrets behind Vitamin C… Is it really good or bad for our health? - comagenius | comagenius | Scoop.it

Researchers have found that Vitamin C can kill multidrug-resistant tuberculosis (MDR-TB). The hypothesis is that vitamin C killed the bacteria by driving an iron-dependent reaction which produces reactive oxygen species and induces cell death via DNA damage. One can ask now, if Vitamin C can kill bacteria by damaging DNA, could  it harm human cells, too?

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41 of 43 patients with HIV stay healthy for over 11 years after initial gene therapy, T-cells perpetuate & persist

41 of 43 patients with HIV stay healthy for over 11 years after initial gene therapy, T-cells perpetuate & persist | comagenius | Scoop.it

HIV patients treated with genetically modified T cells remain healthy up to 11 years after initial therapy, researchers from the Perelman School of Medicine at the University of Pennsylvania report in the new issue of Science Translational Medicine. The results provide a framework for the use of this type of gene therapy as a powerful weapon in the treatment of HIV, cancer, and a wide variety of other diseases.

 

"We have 43 patients and they are all healthy," says senior author Carl June, MD, a professor of Pathology and Laboratory Medicine at Penn Medicine. "And out of those, 41 patients show long term persistence of the modified T cells in their bodies."

 

Early gene therapy studies raised concern that gene transfer to cells via retroviruses might lead to leukemia in a substantial proportion of patients, due to mutations that may arise in genes when new DNA is inserted. The new long-term data, however, allay that concern in T cells, further buoying the hope generated by work June's team published in 2011 showing the eradication of tumors in patients with chronic lymphocytic leukemia using a similar strategy.

 

"If you have a safe way to modify cells in patients with HIV, you can potentially develop curative approaches," June says. "Patients now have to take medicine for their whole lives to keep their virus under control, but there are a number of gene therapy approaches that might be curative." A lifetime of anti-HIV drug therapy, by contrast, is expensive and can be accompanied by significant side effects.

 

They also note that the approach the Penn Medicine team studied may allow patients with cancers and other diseases to avoid the complications and mortality risks associated with more conventional treatments, since patients treated with the modified T cells did not require drugs to weaken their own immune systems in order for the modified cells to proliferate in their bodies after infusion, as is customary for cancer patients who receive stem cell transplants.


Via Dr. Stefan Gruenwald
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Is it possible to make old hearts younger?

Is it possible to make old hearts younger? | comagenius | Scoop.it

Researchers from Harvard Stem Cell Institute (HSCI) and Brigham and Women’s Hospital showed that the answer to this question is YES!

 

“Heart failure constitutes an important medical, social, and economic problem. Although reliable estimates are lacking in many countries, the prevalence of heart failure is estimated as 2%-3% of the adult population and increases with age. Over 26 million people suffer from heart failure around the world and over 3.5 million people are newly diagnosed with heart failure every year in Europe alone. The long-term prognosis associated with heart failure is worse than that associated with the majority of cancers, with 50% mortality after 4 years. Patients suffer disabling symptoms that often become refractory to treatment and need hospitalization, having the greatest negative impact on quality of life compared with other chronic conditions.” written in Medicographia1,2  by J . López-Sendón (MD, PhD Cardiology Department Hospital Universitario La Paz Madrid, SPAIN)

 

In the paper published recently in Cell, it has been shown that a certain type of protein called GDF-11 in the blood of mice and humans may reverse the aging in heart which leads to age-related heart failure. After injecting GDF-11 into old mice with thick heart walls, hearts were shown to reduce their size and thickness like in young mice.

 

As it is mentioned in Harvard gazette3 this finding can change our understanding of aging completely, since the most common form of heart failure is caused by heart aging. Results are very promissing and authors have claimed that “... at least one pathologic component of age-related diastolic heart failure is hormonal in nature and reversible.”4 More intriguingly, it was also mentioned in the paper that the preliminary studies suggest that GDF11 treatment may influence aging phenotypes in other tissues, such as skeletal muscle as well, which makes investigations for determining the role of GDF11 in aging beyond the heart more important.

 

We have to wait now until the time needed for the clinical trials passes to see old people getting their healthy life as if they are young again in near future.

 

1What is Medicographia?

2The heart failure epidemic, J . López-Sendón, Medicographia, 2011;33:363-369

3To read the news in Harvard gazette click here.

4Growth Differentiation Factor 11 Is a Circulating Factor that Reverses Age-Related Cardiac Hypertrophy, Amy J. Wagers and Richard T. Lee et. al. Cell, 2013, 153, 828–839

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University of Georgia stops plant photosynthesis to generate solar power

University of Georgia stops plant photosynthesis to generate solar power | comagenius | Scoop.it

There's a more efficient way to harvest energy from the backyard than by wiring up hapless critters. Researchers at the University of Georgia have proof: they've discovered a way to generate electricity from plants through hijacking the photosynthesis process. By altering the proteins inside a plant cell's thylakoids, which store solar energy, scientists can intercept electrons through a carbon nanotube backing that draws them away before they're used to make sugar. While the resulting power isn't phenomenal, it's still two orders of magnitude better than previous methods, according to the university. The protein modification method may have a rosier future, as well: the team believes that it could eventually compete with solar cells, producing green energy in a very literal sense.

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Can we grow a stronger-than-steel 'wonder material' to save the world?

Can we grow a stronger-than-steel 'wonder material' to save the world? | comagenius | Scoop.it

t’s stiffer than Kevlar, thinner than paper, and in a few years, it may be mass-produced using only sunlight and water.

Scientists in the US this week announced a new, and potentially groundbreaking method for producing nanocellulose — a so-called "wonder material" derived from tree fiber that could be used to create ultra-thin displays, lightweight body armor, and a wide range of other products.

Their key ingredient? Algae.

 

"ONE OF THE MOST IMPORTANT DISCOVERIES IN PLANT BIOLOGY"

 

Dr. R. Malcolm Brown, a biology professor at the University of Texas at Austin, presented his team's findings at an American Chemical Society conference in New Orleans on Sunday, heralding their progress as a major step toward "one of the most important discoveries in plant biology."

At the core of Brown's research is a family of bacteria that produce vinegar, Kombucha tea, and nata de coco. These bacteria secrete nanocellulose in a culture medium, though extracting the material at a large scale would require high volumes of sugars, nutrients, and fermentation tanks. Today, most non-bacterial nanocellulose is produced from compressed and homogenized wood pulp — a relatively inexpensive, but resource-heavy process.

Brown's method, by contrast, is vastly more efficient and environmentally friendly, requiring only sunlight, water, and algae. By genetically engineering vinegar bacterium into blue-green algae, Brown's lab has effectively created organic factories capable of making nanocellulose on a potentially industrial scale.

 

ORGANIC, SELF-SUSTAINING FACTORIES

These genetically-altered algae, known as cyanobacteria, are entirely self-sustaining. They produce their own food from sunlight and water, and absorb carbon dioxide from the atmosphere, offering a natural way to reduce the world's most pernicious greenhouse gas.

The team is currently working on synthesizing a more complete and stable form of the material, though their progress is already promising. If scaled up, Brown's method could have a dramatic impact across several sectors.

Cellulose is the most abundant organic polymer on Earth, forming a major component in tree trunks, dietary fibers, and cotton. Nanocellulose shares some similar properties, though it's notably more versatile — lightweight, stiffer than Kevlar, and, under certain conditions, conductive.

Advances in genetic engineering have only expanded its potential. Last year, researchers in Finland created a nanocellulose aerogel with an incredibly high buoyancy. According to the scientists, a one-pound boat made of this substance would be able to carry up to 1,000 pounds of cargo.

Brown says bacterial nanocellulose can also be used to create ballistic glass, aerospace materials, or even wound dressings, due to the fact that it retains its stiffness and strength even when submerged in liquid. But perhaps its most obvious application would be in the paper and display industry.

THIN, LIGHTWEIGHT, AND REMARKABLY VERSATILE

At a press briefing Sunday, Brown said he and his team have begun adding electrochromic dye to the cellulose to create an electronic display. “I see this as a major development," he said, noting that its thin and flexible qualities make it ideal for electronic wallpaper, as well.

It's unlikely that Brown's material will completely replace traditional paper, but its sustainable qualities present obvious environmental benefits.

"It certainly won't replace or supplant the forest and paper industry, but it could supplement it," Brown said in an interview with The Verge, adding that his technique, if widely adopted, could help reduce deforestation.

Brown's lab is still "five to ten years" away from adapting the process to a large scale, though he says the science behind it is sound. All they need now, the professor explains, is broader awareness and momentum.

Last year, the US Forest Service opened the country's first nanocellulose production facility in Wisconsin, in an effort to take the lead in renewable nanomaterials. After devoting 40 years to nanocellulose research, Brown hopes that his latest developments will encourage similar investments.

"We need to have more funds in this area," Brown told reporters. "So having the chance to tell the world more about this new microorganism will, I think, help tip the funding. I hope so."

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Scientists Engineer Extreme Microorganisms To Make Fuel From Atmospheric Carbon Dioxide

Scientists Engineer Extreme Microorganisms To Make Fuel From Atmospheric Carbon Dioxide | comagenius | Scoop.it

To find a way of fending off global warming, scientists sometimes look to nature. Plants, after all, use photosynthesis to snap up carbon dioxide, the smoggy stuff. 

To find a way of fending off global warming, scientists sometimes look to nature. Plants, after all, use photosynthesis to snap up carbon dioxide, the biggest source of our climate change woes. So we get inventions like artificial leaves and ambitious projects like a plan to give fish photosynthesizing powers. One of the more interesting plans: genetically alter microorganisms so they can chow down on some CO2, too.

University of Georgia researchers recently used the mighty Pyrococcus furiosus, which usually eats carbohydrates and lives in super-heated waters or volcanic marine mud (ideally, for it, at about 100 degrees Celsius). By toying with the genome-sequenced microorganism's genetic material, they were able to make it comfortable in much cooler waters, and to eat carbon dioxide. After that, using hydrogen gas to form a chemical reaction in the microorganism, the researchers got the microorganism to produce 3-hydroxypropionic acid, a common chemical used in household products. That's been done before, but the researchers are looking into turning the process into one that could eventually produce fuel.

If it is able to produce fuel, that wouldn't make it the first bacteria-like organism to do so. Others have been able to make that happen in a lab. But for anyone working on it, the next move after proving it works is scaling up. Then, ideally, we'll start getting water bottles that can power our homes.

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2013 Invention Awards: Smart Ball

2013 Invention Awards: Smart Ball | comagenius | Scoop.it

After an earthquake devastated Haiti in 2010, search-and-rescue teams descended upon Port-au-Prince to look for survivors. Francisco Aguilar, a graduate student in public policy at the time, was shocked to read stories about crews relying on complex, expensive imaging systems. “Only a few teams had them, and you had to be really well trained to use them,” Aguilar says. He soon launched a start-up in Cambridge, Massachusetts, to develop a simple way to explore hard-to-reach places: a throwable, expendable, baseball-size probe.

The Bounce Imaging Explorer has a shock-absorbing shell embedded with six cameras, plus clusters of near-infrared LEDs to light up dark rooms (for the cameras). To deploy the Explorer, an emergency worker links it to a smartphone or tablet and chucks the ball into danger. It immediately begins taking photos and testing for methane, carbon monoxide, and dangerously high temperatures. A microprocessor inside the ball then stiches the photos together and converts the raw data for transmission over Wi-Fi. Just seconds after the toss, a wrap-around panorama—complete with environmental warnings—appears on the synced device.

Aguilar quickly imagined applications beyond disaster areas, such as burning buildings, hostage crises, and combat zones, so he sought feedback from potential customers. His start-up cranked through dozens of prototypes in the first 18 months, tweaking the design as requests poured in. When several police officers said they wanted to be able to hear inside a room, for example, Aguilar added a digital microphone.

Police, firefighters, soldiers, and nuclear-plant inspectors have offered to test the device, which Aguilar is determined to keep between $500 and $1,000. “We want to get it as cheap as possible so it can be as broadly deployed as possible,” he says.

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An electronic nose can tell pears and apples apart

An electronic nose can tell pears and apples apart | comagenius | Scoop.it

Engineers have created a system of sensors that detects fruit odors more effectively than the human sense of smell. For now, the device can distinguish between the odors compounds emitted by pears and apples.

 

Researchers from the Polytechnic University of Valencia (UPV, Spain) and the University of Gävle (Sweden) have created an electronic nose with 32 sensors that can identify the odours given off by chopped pears and apples.

"The fruit samples are placed in a pre-chamber into which an air flow is injected which reaches the tower with the sensors which are metal oxide semiconductors that detect odorous compounds such as methane or butane," explained José Pelegrí Sebastiá, UPV researcher at the Gandia campus and co-author of the paper.

Next, software is used to gather real time data and the information is processed through classification algorithms. The results can be viewed on a 3D graph which distinguishes between the pear and apple scores.

This study, which is published in the 'Sensors and Actuators A' journal, is the starting point for new research the team is already involved in to develop multisensor systems that increase the capacity to differentiate complex mixtures of volatile substances.

"One example would be the wine making sector," Pelegrí commented, "where an electronic nose capable of distinguishing the quality or type of grape or recognising the vintage a wine belongs to would be very useful."

Other lines of research focus on the field of biomedicine. Some studies have shown that trained dogs can detect cancerous tumours, such as lung cancer, by smelling a person's breath.

If this is true, and an electronic nose can detect which substances the animals recognise, then we could diagnose the disease earlier and increase patients' survival rates.

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Creating Indestructible Self-Healing Circuits

Creating Indestructible Self-Healing Circuits | comagenius | Scoop.it

Caltech engineers build electronic chips that repair themselves

 

PASADENA, Calif.—Imagine that the chips in your smart phone or computer could repair and defend themselves on the fly, recovering in microseconds from problems ranging from less-than-ideal battery power to total transistor failure. It might sound like the stuff of science fiction, but a team of engineers at the California Institute of Technology (Caltech), for the first time ever, has developed just such self-healing integrated chips.

The team, made up of members of the High-Speed Integrated Circuits laboratory in Caltech's Division of Engineering and Applied Science, has demonstrated this self-healing capability in tiny power amplifiers. The amplifiers are so small, in fact, that 76 of the chips—including everything they need to self-heal—could fit on a single penny. In perhaps the most dramatic of their experiments, the team destroyed various parts of their chips by zapping them multiple times with a high-power laser, and then observed as the chips automatically developed a work-around in less than a second.

"It was incredible the first time the system kicked in and healed itself. It felt like we were witnessing the next step in the evolution of integrated circuits," says Ali Hajimiri, the Thomas G. Myers Professor of Electrical Engineering at Caltech. "We had literally just blasted half the amplifier and vaporized many of its components, such as transistors, and it was able to recover to nearly its ideal performance."

The team's results appear in the March issue of IEEE Transactions on Microwave Theory and Techniques.

Until now, even a single fault has often rendered an integrated-circuit chip completely useless. The Caltech engineers wanted to give integrated-circuit chips a healing ability akin to that of our own immune system—something capable of detecting and quickly responding to any number of possible assaults in order to keep the larger system working optimally. The power amplifier they devised employs a multitude of robust, on-chip sensors that monitor temperature, current, voltage, and power. The information from those sensors feeds into a custom-made application-specific integrated-circuit (ASIC) unit on the same chip, a central processor that acts as the "brain" of the system. The brain analyzes the amplifier's overall performance and determines if it needs to adjust any of the system's actuators—the changeable parts of the chip.

Interestingly, the chip's brain does not operate based on algorithms that know how to respond to every possible scenario. Instead, it draws conclusions based on the aggregate response of the sensors. "You tell the chip the results you want andlet it figure out how to produce those results," says Steven Bowers, a graduate student in Hajimiri's lab and lead author of the new paper. "The challenge is that there are more than 100,000 transistors on each chip. We don't know all of the different things that might go wrong, and we don't need to. We have designed the system in a general enough way that it finds the optimum state for all of the actuators in any situation without external intervention."

Looking at 20 different chips, the team found that the amplifiers with the self-healing capability consumed about half as much power as those without, and their overall performance was much more predictable and reproducible. "We have shown that self-healing addresses four very different classes of problems," says Kaushik Dasgupta, another graduate student also working on the project. The classes of problems include static variation that is a product of variation across components; long-term aging problems that arise gradually as repeated use changes the internal properties of the system; and short-term variations that are induced by environmental conditions such as changes in load, temperature, and differences in the supply voltage; and, finally, accidental or deliberate catastrophic destruction of parts of the circuits.

The Caltech team chose to demonstrate this self-healing capability first in a power amplifier for millimeter-wave frequencies. Such high-frequency integrated chips are at the cutting edge of research and are useful for next-generation communications, imaging, sensing, and radar applications. By showing that the self-healing capability works well in such an advanced system, the researchers hope to show that the self-healing approach can be extended to virtually any other electronic system.

"Bringing this type of electronic immune system to integrated-circuit chips opens up a world of possibilities," says Hajimiri. "It is truly a shift in the way we view circuits and their ability to operate independently. They can now both diagnose and fix their own problems without any human intervention, moving one step closer to indestructible circuits."

Along with Hajimiri, Bowers, and Dasgupta, former Caltech postdoctoral scholar Kaushik Sengupta (PhD '12), who is now an assistant professor at Princeton University, is also a coauthor on the paper, "Integrated Self-Healing for mm-Wave Power Amplifiers." A preliminary report of this work won the best paper award at the 2012 IEEE Radio Frequency Integrated Circuits Symposium. The work was funded by the Defense Advanced Research Projects Agency and the Air Force Research Laboratory.

Written by Kimm Fesenmaier
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Heroin Vaccine Treats Drug Addiction in Rats

Heroin Vaccine Treats Drug Addiction in Rats | comagenius | Scoop.it

Relapse can be a particularly sinister aspect of drug addiction. Now scientists are getting closer to a vaccine that can bind heroin in the bloodstream and therefore prevent it from acting on the brain.

A heroin vaccine has been sought after for some time to treat those with serious addictions. Like a vaccine for the flu or measles, a heroin vaccine would contain inactive pieces of the drug; this would train the immune system in the future to attack heroin in the bloodstream. The challenge has been that heroin breaks down quickly into other molecules in the bloodstream.

Researchers have now gotten around that by creating a heroin vaccine that also works on these breakdown molecules. They started with populations of rats that had been exposed to heroin in the past. Three doses of the vaccine were given to a subset of the group over a 28-day period.

 

To test the vaccine efficacy, they then gave rats heroin injections and took blood samples. In vaccinated rats, more heroin-breakdown molecules were found in the bloodstream, which means less heroin was getting into the rats’ brains than in unvaccinated rats.

Then researchers tested how the vaccine changed rat behavior. In one test, rats were given three heroin doses (simulating a relapse) before they went through two-hour sessions in which pressing a lever gave them no heroin. Those that were not vaccinated pressed the lever repeatedly in search of more of the drug; those rats given the vaccine didn’t bother to tap the lever for another dose of heroin when prompted.

In another test, heroin-dependent rats were forced to abstain for a month and then given the drug again. While the non-vaccinated rats rapidly escalated their heroin dosing when given renewed access to the drug, those that were vaccinated showed steady heroin intake instead of increases and they no longer showed signs of addiction. The results are published today inProceedings of the National Academy of Sciences.

“Basically we were able to stop them from going through that cycle of taking more and more heroin,” says Joel Schlosburg, a postdoctoral research associate at the Scripps Research Institute and an author of the study. “And that was with the vaccine alone; ideally for human patients the vaccine would be given with other treatments.”

Researchers have found that the vaccine doesn’t block the effectiveness of heroin treatment options already being used in people, such as methadone and buprenorphine, which is a plus. The vaccine must now go through clinical trials in humans.

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Molecular machine could hold key to more efficient manufacturing

Molecular machine could hold key to more efficient manufacturing | comagenius | Scoop.it

The artificial molecular machine developed by Professor David Leigh FRS and his team in the School of Chemistry is the most advanced molecular machine of its type in the world. Its development has been published in the journal Science.

Professor Leigh explains: “The development of this machine which uses molecules to make molecules in a synthetic process is similar to the robotic assembly line in car plants. Such machines could ultimately lead to the process of making molecules becoming much more efficient and cost effective. This will benefit all sorts of manufacturing areas as many manmade products begin at a molecular level. For example, we’re currently modifying our machine to make drugs such as penicillin.”  


The machine is just a few nanometres long (a few millionths of a millimetre) and can only be seen using special instruments. Its creation was inspired by natural complex molecular factories where information from DNA is used to programme the linking of molecular building blocks in the correct order. The most extraordinary of these factories is the ribosome, a massive molecular machine found in all living cells. 

Professor Leigh’s machine is based on the ribosome. It features a functionalized nanometre-sized ring that moves along a molecular track, picking up building blocks located on the path and connecting them together in a specific order to synthesize the desired new molecule.  

First the ring is threaded onto a molecular strand using copper ions to direct the assembly process. Then a “reactive arm” is attached to the rest of the machine and it starts to operate. The ring moves up and down the strand until its path is blocked by a bulky group. The reactive arm then detaches the obstruction from the track and passes it to another site on the machine, regenerating the active site on the arm. The ring is then free to move further along the strand until its path is obstructed by the next building block. This, in turn, is removed and passed to the elongation site on the ring, thus building up a new molecular structure on the ring. Once all the building blocks are removed from the track, the ring de-threads and the synthesis is over.

Professor Leigh says the current prototype is still far from being as efficient as the ribosome: “The ribosome can put together 20 building blocks a second until up to 150 are linked. So far we have only used our machine to link together 4 blocks and it takes 12 hours to connect each block. But you can massively parallel the assembly process: We are already using a million million million (1018) of these machines working in parallel in the laboratory to build molecules.” 

Professor Leigh continues: “The next step is to start using the machine to make sophisticated molecules with more building blocks. The potential is for it to be able to make molecules that have never been seen before. They’re not made in nature and can’t be made synthetically because of the processes currently used. This is a very exciting possibility for the future.”  

 
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Marijuana May Cure Cancer! - comagenius

Marijuana May Cure Cancer! - comagenius | comagenius | Scoop.it
Marijuana May Cure Cancer!
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Peer-reviewed scientific studies in several countries show THC and other compounds found only in marijuana are effective not only for cancer symptom management (pain, nausea, loss of appetite, fatigue, and so on), but they confer a direct antitumoral effect as well. 
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Breaking the 100% Quantum Efficiency in Solar Cells - comagenius

Breaking the 100% Quantum Efficiency in Solar Cells - comagenius | comagenius | Scoop.it

Researchers have found the way to convert light into electricity much         more efficiently than current photovoltaic devices can achieve.


Being available in a never-ending supply, the sun is considered as one of the most powerful renewable energy sources.When the first solar cell was introduced into the photovoltaic field, converting the energy of sunlight into electricity seemed to be a great idea of scientists. Soon after, however, it was realized that the materials used in the active layer of photovoltaic cells limit the conversion of photons in the sunlight to current, which proves the low efficiency of solar cells.In principle, solar spectrum involves a range of photons with different energies. However, low energy photons cannot be used in energy conversion and high energy photons produce heat with the excessive energy that they carry.
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Angelina Jolie's surgical removal of her breast tissue - action of panic or life-prolonging act? - - comagenius

Angelina Jolie's surgical removal of her breast tissue - action of panic or life-prolonging act? - - comagenius | comagenius | Scoop.it

Hollywood star Angelina Jolie has attracted much attention with her surgical removal of the tissue of both breasts, called double mastectomy, to significantly reduce the chance of developing breast cancer. She received much encouragement and is already a model for some people. However, in the following week an open discussion raised if this step was necessary and applicable to other people with similar problems.


On April 27 Angelina Jolie finished a three month of medical treatment that involved three critical steps: a procedure known as ‘nipple delay’, which targets the breast ducts behind the nipple with the purpose of saving the nipple, the major surgery, during which the whole breast tissue is removed and filled with temporally filling material instead, and the final reconstruction of the breast with an implant. Two weeks later she was sharing her story with the public that “women can benefit from (her) experience”  publishing it in The New York Times under the title ‘My Medical Choice’.1 “I wanted to write this to tell other women that the decision to have a mastectomy was not easy but it is one I am very happy that I made. My chances of developing breast cancer have dropped from 87 percent to under 5 percent. I can tell my children that they don’t need to fear they will lose me to breast cancer,” the actress said. This induced a worldwide reactions most paying their respect for her brave behavior, both in doing the surgery and sharing this private matter with the world: “Brave, honest strong,” said Oscar winner Marlee Matlin. “She’ll have empowered millions of women all over world. She is sexier than ever,” said Sharon Osbourne, who did the same preventive procedure. “Angelina Jolie, thank you for sharing your story and helping women around the world inspirational,” wrote singer and breast cancer survivor Kylie Minogue.
However, there were also people that had concerns about the wide-spread discussion like H. Gilbert Welch, a professor of medicine at the Dartmouth Institute for Health Policy and Clinical Practice and a co-author of "Overdiagnosed: Making People Sick in the Pursuit of Health." In an article published on CNN he cited a research fellow at the International Agency for Research on Cancer, who summed up the general risk: "I fear that this disclosure will motivate other women to undergo preventive mastectomy, even though they do not need it."2 And indeed there is a higher activity since the story was published: "Before the news of Angelina Jolie once a week a woman called, now there are five a day," Dr. Ines Schönbuchner says, working at the Center for Familial Breast and Ovarian Cancer at the University Hospital in Regensburg, Germany. Also Peggy Orenstein recently wrote about her own experience and the downsides of cancer awareness in a much talked about cover story for the Times' Sunday Magazine called "Our Feel-Good War on Breast Cancer."3 She says: "I feel that it's really important that women recognize that Angelina Jolie is in this very particular group of women that has this genetic mutation. She's not a woman of average risk, and to take her experience and generalize it either to ordinary women of average risk or even women with a family history, that concerns me." The mutation she mentioned is located on the gene BRCA1. And even though the risk to develop cancer is significantly increased with this mutation, two things are important to mention: first, faults in the BRCA1 gene are rare and in most cases were linked to family history. Dr Richard Francis, head of research at Breakthrough Breast Cancer: "Though Angelina decided that a preventative mastectomy was the right choice for her, this may not be the case for another woman in a similar situation.”4 Second, the moment of onset can vary considerably. A study by Sylvia K. Plevritis and coworkers conducted at the Stanford University and published last year in Cancer Epidemiology, Biomarkers & Prevention showed that the removal of both breasts and ovaries (prophylactic mastectomy and oophorectomy) after a positive BRCA1 test results in a gain of life expectancy of up to 10.3 years. However, adding annual breast screening provides also gains up to 9.9 years.5 Thus technically the difference between prophylactic surgery and annual breast screenings is inconsiderable.Alice Schwarzer, the most prominent contemporary German feminist and founder and publisher of the German feminist journal Emma argued from another point of view: "This alienated, mechanical relationship to her own body does not account for the complex interplay of a body, including the role of psychological influences. Jolie's operation is neither courageous nor cowardly, it is a panic action and panic is a bad counselor."6 Other people criticize the position of the women in this discussion. “To me, the bitter thought that not possible illness, but the image of how you look, is at the forefront of the debate. How preposterous that a woman's value is to be adjusted according to what happens to her breasts. Maybe Jolie will help with her story, to solve one or another of its fixation. Women are not innocent in this picture, because many of us are very embarrassed if our breasts are too small, too flabby, too big or whatever natured,” Hatice Akyün commented in Der Tagesspiegel titled “Breasts in the head”.7The tacky offer of the ‘Playboy’ to pay any amount of money to pose for their magazine as soon as Jolie’s breasts are healed from her reconstructive surgery underlines that the image of the woman rather than the illness is the real topic of this discussion.8



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Leprosy Reprograms the Body | Wired Science | Wired.com

Leprosy Reprograms the Body | Wired Science | Wired.com | comagenius | Scoop.it

Leprosy has plagued humans for thousands of years, but that doesn’t mean it has revealed all of its secrets. A new study in mice suggests the disfiguring disease employs a bit of biological trickery to do its damage: It reprograms certain nerve cells to become like stem cells and uses them to infiltrate the body’s muscle and nervous systems. This is the first time that scientists have seen bacteria reprogram cells in this way, and experts say the find could lead to the development of new treatments for leprosy and other neurodegenerative diseases.

 

More than 200,000 people worldwide are diagnosed with leprosy (also known as Hansen’s disease) each year. Despite its ancient origins and almost mythic status, however, leprosy remains mysterious. Researchers know that it’s caused by the bacteriumMycobacterium leprae, and that it leaves sufferers with deforming lesions and a debilitating loss of sensation in their hands and feet. But they don’t know how the infection spreads throughout the body or why it damages nerves so extensively. In part, that’s because it’s hard to investigate: the bacterium that causes leprosy can’t be grown in a lab, so it can only be studied in infected humans, armadillos, and genetically engineered mice.

To answer some of those lingering questions, biologist Anura Rambukkana of the University of Edinburgh in the United Kingdom and his colleagues seized on another known detail of the disease: its predilection for infecting Schwann cells, specialized cells that sheathe the nerves and help transmit nervous system signals. The researchers isolated Schwann cells from mice and infected them with M. leprae—and were soon surprised by what they saw.

 

The bacteria transformed the cells, turning off genes that were expressed in mature Schwann cells and turning on genes associated with earlier stages of cell development. The cells became immature and, like certain kinds of stem cells found in bone marrow and other tissues, could now turn into bone and muscle cells. “We thought, ‘Oh, my God, this is a vehicle for going anywhere in the body,’ ” Rambukkana recalls.

When the team reintroduced the altered cells into the mice, some of the cells migrated to muscle tissues and spread the bacteria wherever they went. The results suggest that M. leprae hijacks Schwann cells, destroying their ability to insulate and support the nervous system, so it can use them to infiltrate other tissues in the body, the team reports online today in Cell.

Rambukkana hopes that future studies will shed more light on how the leprosy bacterium transforms Schwann cells. Understanding the process could help doctors diagnose leprosy at earlier stages and possibly stop it in its tracks, he says. “It can also help us find new ways to generate stem cells for therapeutic approaches, so we can treat other neurodegenerative diseases,” such as multiple sclerosis.

There’s one caveat, says developmental neurobiologist Michael Wegner of the University of Erlangen-Nuremberg in Germany who was not involved in the study. The study doesn’t prove that M. leprae co-opts human Schwann cells in the same way, he notes. But it does offer a plausible mechanism in “a fascinating study that uses state-of-the-art methodology.”

Dermatologist and leprosy researcher Robert Modlin of the David Geffen School of Medicine at the University of California, Los Angeles, agrees. “I was amazed—this is a really creative, out-of-the-box study,” Modlin says. “It raises mind-provoking questions about how it could relate to humans. It has real potential.”

By Gisela Telis, ScienceNOW

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Perpetual Motion Test Could Amend Theory of Time

Perpetual Motion Test Could Amend Theory of Time | comagenius | Scoop.it
A radical theory predicting the existence of “time crystals” — perpetual motion objects that break the symmetry of time — is being put to the test.

 

n February 2012, the Nobel Prize-winning physicist Frank Wilczek decided to go public with a strange and, he worried, somewhat embarrassing idea. Impossible as it seemed, Wilczek had developed an apparent proof of “time crystals” — physical structures that move in a repeating pattern, like minute hands rounding clocks, without expending energy or ever winding down. Unlike clocks or any other known objects, time crystals derive their movement not from stored energy but from a break in the symmetry of time, enabling a special form of perpetual motion.

“Most research in physics is continuations of things that have gone before,” said Wilczek, a professor at the Massachusetts Institute of Technology. This, he said, was “kind of outside the box.”

Wilczek’s idea met with a muted response from physicists. Here was a brilliant professor known for developing exotic theories that later entered the mainstream, including the existence of particles called axions and anyons, and discovering a property of nuclear forces known as asymptotic freedom (for which he shared the Nobel Prize in physics in 2004). But perpetual motion, deemed impossible by the fundamental laws of physics, was hard to swallow. Did the work constitute a major breakthrough or faulty logic? Jakub Zakrzewski, a professor of physics and head of atomic optics at Jagiellonian University in Poland who wrote a perspective on the research that accompanied Wilczek’s publication, says: “I simply don’t know.”

Now, a technological advance has made it possible for physicists to test the idea. They plan to build a time crystal, not in the hope that this perpetuum mobile will generate an endless supply of energy (as inventors have striven in vain to do for more than a thousand years) but that it will yield a better theory of time itself.

A Crazy Concept

The idea came to Wilczek while he was preparing a class lecture in 2010. “I was thinking about the classification of crystals, and then it just occurred to me that it’s natural to think about space and time together,” he said. “So if you think about crystals in space, it’s very natural also to think about the classification of crystalline behavior in time.”

When matter crystallizes, its atoms spontaneously organize themselves into the rows, columns and stacks of a three-dimensional lattice. An atom occupies each “lattice point,” but the balance of forces between the atoms prevents them from inhabiting the space between. Because the atoms suddenly have a discrete, rather than continuous, set of choices for where to exist, crystals are said to break the spatial symmetry of nature — the usual rule that all places in space are equivalent. But what about the temporal symmetry of nature — the rule that stable objects stay the same throughout time?

The Nobel Prize-winning physicist Frank Wilczek often develops outlandish theories that eventually enter the mainstream. “Of course not everything I do works,” he says. (Photo: Courtesy of Frank Wilczek)

Wilczek mulled over the possibility for months. Eventually, his equations indicated that atoms could indeed form a regularly repeating lattice in time, returning to their initial arrangement only after discrete (rather than continuous) intervals, thereby breaking time symmetry. Without consuming or producing energy, time crystals would be stable, in what physicists call their “ground state,” despite cyclical variations in structure that scientists say can be interpreted as perpetual motion.

“For a physicist, this is really a crazy concept to think of a ground state which is time-dependent,” said Hartmut Häffner, a quantum physicist at the University of California, Berkeley. “The definition of a ground state is that this is energy-zero. But if the state is time-dependent, that implies that the energy changes or something is changing. Something is moving around.”

How can something move, and keep moving forever, without expending energy? It seemed an absurd idea — a major break from the accepted laws of physics. But Wilczek’s papers on quantumand classical time crystals (the latter co-authored by Alfred Shapere of the University of Kentucky) survived a panel of expert reviewers and were published in Physical Review Letters in October 2012. Wilczek didn’t claim to know whether objects that break the symmetry of time exist in nature, but he wanted experimentalists to try to make one.

“It’s like you draw targets and wait for arrows to hit them,” he said. “If there’s no logical barrier to this behavior being realized, then I expect it will be realized.”

The Big Test

In June, a group of physicists led by Xiang Zhang, a nanoengineer at Berkeley, and Tongcang Li, a physicist and postdoctoral researcher in Zhang’s group, proposed creating a time crystal in the form of a persistently rotating ring of charged atoms, or ions. (Li said he had been contemplating the idea before reading Wilczek’s papers.) The group’s article was published with Wilczek’s in Physical Review Letters.

Since then, a single critic — Patrick Bruno, a theoretical physicist at the European Synchrotron Radiation Facility in France — has voiced dissent in the academic literature. Bruno thinks Wilczek and company mistakenly identified time-dependent behavior of objects in excited energetic states, rather than their ground states. There is nothing surprising about objects with surplus energy moving in a cyclical fashion, with the motion decaying as the energy dissipates. To be a time crystal, an object must exhibit perpetual motion in its ground state.

Bruno’s comment and Wilczek’s reply appeared in Physical Review Letters in March 2013. Bruno demonstrated that a lower energy state is possible in a model system that Wilczek had proposed as a hypothetical example of a quantum time crystal. Wilczek said that although the example is not a time crystal, he doesn’t think the error “calls into question the basic concepts.”

“I proved that example is not correct,” Bruno said. “But I have no general proof — so far, at least.”

The debate will probably not be settled on theoretical grounds. “The ball is really in the hands of our very clever experimental colleagues,” Zakrzewski said.

An international team led by Berkeley scientists is preparing an elaborate lab experiment, although it may take “anywhere between three and infinity years” to complete, depending on funding or unforeseen technical difficulties, said Häffner, who is co-principal investigator with Zhang. The hope is that time crystals will push physics beyond the precise but seemingly imperfect laws of quantum mechanics and lead the way to a grander theory.

“I’m very interested in seeing if I can make a new contribution following Einstein,” Li said. “He said that quantum mechanics is not complete.”

To Build an Ion Ring

In Albert Einstein’s theory of general relativity (the body of laws governing gravity and the large-scale structure of the universe), the dimensions of time and space are woven together into the same fabric, known as space-time. But in quantum mechanics (the laws governing interactions on the subatomic scale), the time dimension is represented in a different way than the three dimensions of space — “a disturbing, aesthetically unpleasant asymmetry,” Zakrzewski said.

The different treatments of time may be one source of incompatibility between general relativity and quantum mechanics, at least one of which must be altered for there to be an all-encompassing theory of quantum gravity (widely viewed as a major goal of theoretical physics). Which concept of time is right?

If time crystals are able to break time symmetry in the same way that conventional crystals break space symmetry, “it tells you that in nature those two quantities seem to have similar properties, and that ultimately should reflect itself in a theory,” Häffner said. This would suggest that quantum mechanics is inadequate, and that a better quantum theory might treat time and space as two threads of the same fabric.

An illustration of the time crystal experiment planned at UC-Berkeley. Electric fields will be used to corral calcium ions into a 100-micron-wide “trap,” where they will form a crystalline ring. The scientists believe a static magnetic field will cause the ring to rotate. (Illustration: Courtesy of Hartmut Häffner)

The Berkeley-led team will attempt to build a time crystal by injecting 100 calcium ions into a small chamber surrounded by electrodes. The electric field generated by the electrodes will corral the ions in a “trap” 100 microns wide, or roughly the width of a human hair. The scientists must precisely calibrate the electrodes to smooth out the field. Because like charges repel, the ions will space themselves evenly around the outer edge of the trap, forming a crystalline ring.

At first, the ions will vibrate in an excited state, but diode lasers like those found in DVD players will be used to gradually scatter away their extra kinetic energy. According to the group’s calculations, the ion ring should settle into its ground state when the ions are laser-cooled to around one-billionth of a degree above absolute zero. Access to this temperature regime had long been obstructed by background heat emanating from trap electrodes, but in September, a breakthrough technique for cleaning surface contaminants off electrodes enabled a 100-fold reduction in ion trap background heat. “That’s exactly the factor we need to bring this experiment into reach,” Häffner said.

Next, the researchers will switch on a static magnetic field in the trap, which their theory says should induce the ions to start rotating (and continue doing so indefinitely). If all goes as planned, the ions will cycle around to their starting point at fixed intervals, forming a regularly repeating lattice in time that breaks temporal symmetry.

To see the ring’s rotation, the scientists will zap one of the ions with a laser, effectively tagging it by putting it into a different electronic state than the other 99 ions. It will stay bright  (and reveal its new location) when the others are darkened by a second laser.

If the bright ion is circling the ring at a steady rate, then the scientists will have demonstrated, for the first time, that the translational symmetry of time can be broken. “It will really challenge our understanding,” Li said. “But first we need to prove that it does indeed exist.”

Until that happens, some physicists will remain deeply skeptical. “I personally think it’s not possible to detect motion in the ground state,” Bruno said. “They may be able to make a ring of ions in a toroidal trap and do some interesting physics with that, but they will not see their ever-ticking clock as they claim.”

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Scientists Invent Oxygen Particle That If Injected, Allows You To Live Without Breathing

Scientists Invent Oxygen Particle That If Injected, Allows You To Live Without Breathing | comagenius | Scoop.it

A team of scientists at the Boston Children’s Hospital have invented what is being considered one the greatest medical breakthroughs in recent years. They have designed a microparticle that can be injected into a person’s bloodstream that can quickly oxygenate their blood. This will even work if the ability to breathe has been restricted, or even cut off entirely. 


This finding has the potential to save millions of lives every year. The microparticles can keep an object alive for up to 30 min after respiratory failure. This is accomplished through an injection into the patients’ veins. Once injected, the microparticles can oxygenate the blood to near normal levels. This has countless potential uses as it allows life to continue when oxygen is needed but unavailable. For medical personnel, this is just enough time to avoid risking a heart attack or permanent brain injury when oxygen is restricted or cut off to patients.

Dr. John Kheir, who first began the study, works in the Boston Children’s Hospital Department of Cardiology. He found inspiration for the drug in 2006, when he was treating a girl in the ICU who had a severe case of pneumonia. At the time, the girl didn’t have a breathing tube, when at the time she suffered from a pulmonary hemorrhage. This means her lungs had begin to fill up with blood, and she finally went into cardiac arrest. It took doctors about 25 minutes to remove enough blood from her lungs to allow her to breath. Though, the girl’s brain was severely injured due to being deprived of oxygen for that long and she eventually died.

Microparticle Composition

The microparticles used are composed of oxygen gas pocketed in a layer of lipids. A Lipid is a natural molecule that can store energy and act as a part of a cell membrane, they can be made of many things such as wax, vitamins, phospholipids, and in this case fat is the lipid that stores the oxygen.

These microparticles are around two to four micrometers in length and carry about three to four times the oxygen content of our own red blood cells. In the past, researchers had a difficult time succeeding as prior tests caused gas embolism. This meant that the gas molecules would become stuck trying to squeeze through the capillaries. They corrected this issue by packaging them into small deformable particles rather ones where the structure was rigid.

Potential Future Uses

Medical: There is the obvious medical uses where the microparticles can be used to save off death from a restriction in breathing due to inflammation of the lungs, collapsed lungs, and the like. It would be good to have these injections ready in hospitals and ambulances for when the time is needed.

Military: Can you imagine a navy seals capability when they wouldn’t need to surface for air and could stay underwater for over 20 minutes? If a boat was to begin to sink, you could shoot yourself as the boat is going down to ensure you aren’t drowned in the under current of the sinking vessel. How about for toxic gases when a facemask is unavailable. The military could have a number of uses for such a medical advancement.

Private Sector: Really this can be used as a precaution for anything nautical where the potential to drown is a real danger. Deep sea rescue crews could inject themselves prior to making a rescue, underwater welders can use it in case they become stuck or air is lost to their suits. The potential use for anything water related seems extremely worthwhile.

Conclusion

In the end, this is an amazing medical advancement and I cant help but recall the movie the Abyss when they took the pill, their helmets filled with air, and they were told they can breathe the water. Well what if they really couldn’t “breathe” water” but since the urge to breathe is natural, that must take place… even if you’re not breathing air per se. But your body was provided with enough oxygen for a time period by taking a pill. It’s just goes to show that anything, absolutely anything that can be thought up, can potentially one day become reality. Thank you scientists, for reminding me that people and their ingenuity are nothing short of awesome.

The author of this article is Damien S. Wilhelmi, an SEO tactician and SEM strategist. If you enjoyed this article, you can follow me on twitter @JakabokBotch. I am writing on behalf of Wilderness Aware Rafting who offer some of the best Colorado White Water Rafting trips in the state.

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Synthetic spider venom makes a kinder, safer antidote - health

Synthetic spider venom makes a kinder, safer antidote - health | comagenius | Scoop.it

In some countries, arachnophobia is justified. In Brazil, for example, the brown Loxosceles intermedia spiders, also known as reapers or fiddle-backs after their markings, bite 7000 people a year, causing fatal kidney failure in 1.5 per cent of them. There is an antivenom, but it's not ideal.

Now, researchers have devised a synthetic antidote to a Loxosceles bite. It promises fewer side effects than existing treatments and reduces the suffering of the animals required to produce it.

One day, it may also lead to a vaccine against spider bites.

Normally, antivenom is made by injecting horses with venom extracted from the spider. This stimulates the animals to produce antibodies against the toxin but they often develop symptoms, which suggests it is a painful process.

A serum containing these antibodies is then taken from the horses and given to bite victims. The serum soaks up the toxin, but recipients often develop allergic and other potentially life-threatening reactions to other components in the serum.

A team led by Carlos Chávez-Olórtegui of the Federal University of Mias Gerais in Brazil has developed an alternative.

Non-poisonous poison

The researchers identified three surface features of the spider toxin that most strongly trigger antibody production. They inserted the genes encoding these surface features into E. coli bacteria, which subsequently churned out a venom-like substance not found in nature. Because this "venom" contained only these few proteins, it was no longer toxic.

When the synthetic "venom" was injected into rabbits to produce an antibody serum, none suffered adverse reactions.

This serum was then given to other rabbits to see how well it neutralised spider venom. In standard tests, it performed almost as well as serum generated from the real toxin, almost matching its ability to prevent skin and blood damage from the toxin, although it didn't prevent swelling from occurring as well.

The idea is to inject the harmless synthetic "venom" into horses instead of using spider venom, so the horses wouldn't have to endure the toxic effects of the real venom. Plus, because the synthetic version only contains the ingredients necessary to trigger an immune reaction, the horses should generate a narrower range of antibodies, hopefully resulting in fewer side effects when given to humans.

Because it's non-toxic, the synthetic "venom" might even be suitable for vaccinating people. "If they get bitten, they'll already have antibodies capable of neutralising the most harmful effects of the venom," says Chávez-Olórtegui.

Rob Harrison from the Liverpool School of Tropical Medicine in the UK, who in 2006 developed an artificial snake antivenom, doubts whether the vaccine idea would be economical, but agrees that the synthetic protein has huge promise for serum development.

Journal reference: Vaccine, DOI: 10.1016/j.vaccine.2013.03.048

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2013 Invention Awards: Family Flier

2013 Invention Awards: Family Flier | comagenius | Scoop.it

John McGinnis thinks ordinary families would rather skip the airport and fly themselves. So he is trying to reinvent the personal airplane with the help of his father, son, and a rotating crew of about two dozen volunteers. Unlike small aircraft today—which can cost more than a house—McGinnis says Synergy could be cheaper, quieter, and, at more than 40 mpg, three times as fuel-efficient.

McGinnis, a 47-year-old composite manufacturer, flew his first airplane in second grade. Perplexed by the inefficiencies of personal aircraft, he taught himself aeronautical engineering and fluid dynamics over two decades. One day, while perusing scientific studies at a desk in his daughters’ bedroom, he read a NASA researcher’s paper challenging a classic aerodynamic drag equation. McGinnis could see the possibilities. “I came out of the girls’ bedroom ranting like a madman to my wife,” he says. “ ‘Honey, you’re never going to believe this. I think I just solved a problem I’ve been working on since I was a little kid.’”

Synergy’s wings bend upward and into a box shape for minimum drag and maximum efficiency. The top half of each wing swoops behind the body to function as a tail while providing greater in-flight stability. The double-box tail design also makes gliding easier by counteracting tornado-like vortices at the wings’ tips. And instead of a front-mounted propeller, an impeller placed behind the bullet-shaped body quiets noise while adding thrust.

 

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College Students Make First-Ever Successful Flight And Landing Of A Concrete Airplane

College Students Make First-Ever Successful Flight And Landing Of A Concrete Airplane | comagenius | Scoop.it

Throughout the storied history of aviation, humankind has fought to slip the surly bonds of Earth using heavier and heavier things. To do it, airplanes need to be lightweight, or have really big wings and a lot of speed. But can a heavy, slow object get off the ground? To find out, a trio of students from South Dakota School of Mines & Technology set out to make aviation history. They built a super-heavy, completely impractical airplane: One made from concrete. And it worked. Kind of.

It did not soar. It did not travel far. It did not get more than a few inches off the ground, and it did not fly straight. It flipped over and crashed, is what it did. But it got off the ground, flew, landed, and survived!

The only other concrete airplane known to have flown was built at Embry-Riddle Aeronautical University in Daytona Beach, Fla., a prestigious flight school. But that plane was destroyed when it crashed. Not so for this hardy plane from the Great Plains. The main goal was for it to take off and survive landing: Mission accomplished.

David Haberman and Tyler Pojanowski, both mechanical engineering majors, and Seth Adams, a civil and environmental engineering major, worked on the plane for a year. Pojanowski recalls that he was afraid of what would happen, even though his calculations said it would work.

“There wasn’t much time because once it got air it just went over, it flipped over. I was freaked because I was really close to it and was worried it was going to hit me,” Pojanowski says in a news release.

Haberman said he saw a puff of smoke and thought the plane had exploded. It only sustained a crack in the fuselage and wing, but was otherwise OK.

“Everything in aviation you want to be high-strength and low-weight, and concrete is the exact opposite. That’s why the professors did the project, to challenge engineers, to see what we could do,” Haberman said.

The students think it worked in part because of a special university concrete blend, which was developed for another totally bizarre engineering project, a concrete canoe. Because why not.

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Proba-V satellite to track aircraft continuously from space

Proba-V satellite to track aircraft continuously from space | comagenius | Scoop.it

When it comes to keeping tabs on the location of aircraft, radar has long ruled the roost. But radar range is limited, and long-haul planes become untraceable when passing over oceans and large deserts or polar regions. By equipping orbiting satellites with instruments that listen in on ADS-B signals, scientists think that it should possible to track aircraft over the course of their entire journey, and with the launch of Proba-V, they're ready to put the idea to the test.

ADS-B stands for Automatic Dependent Surveillance – Broadcast. It's a safety system designed to supplement, and perhaps one day replace, radar. Aircraft equipped with ADS-B monitor their own location using GPS, and constantly report that data to other aircraft and Air Traffic Control using a data link transmitter. According to Flightradar24, 70 percent of all passenger aircraft in Europe are equipped with ADS-B, and though the equivalent statistic is 30 percent in the US, by 2020 ADS-B will be mandated on all flights that require transponders today. Being more accurate than radar, it's hoped ADS-B will allow a higher volume of air traffic in already-busy airspaces. However, whether air-to-air or air-to-ground, its range is limited to about 200 to 250 nautical miles (370 to 460 km), which is insufficient for keeping a permanent eye on a long-haul passenger jet. From space, however, it could be a different story.

Though ADS-B requires GPS satellites to ascertain its position, they play no part in actual monitoring (GPS satellites are dumb, to all intents and purposes). But on Tuesday, the ESA's Vega rocket took off from French Guiana carrying the Proba-V satellite. It's main mission is to monitor changes in Earth's vegetation, but it is also equipped with a receiver to pick up ADS-B signals from its altitude of 820 km (509 miles). Over the next two years, scientists at the German Aerospace Center (DLR) will monitor proceedings to see if it might be possible for satellites to monitor aircraft over their entire journey.

The DLR has cause for optimism. In 2009, a high-altitude balloon drifting some 30 km (19 miles) above the North Sea equipped with the same ADS-B receiver aboard the satellite was able to pick up a flight en route to Amsterdam from Beijing at a distance of 1,100 km (680 miles). In 2012 a second balloon test at an altitude of 40 km (25 miles) investigated the potential for interference from multiple signals and radar.

Yet the work is in its early stages and the researchers say that the first tests will be to work out the limits of the receiver. From there they can start finding answers to their questions, such as the possible range of monitoring air traffic from space using ADS-B.

Later this year, DLR's AISat satellite will enter orbit to monitor maritime traffic using a 4-meter helical aerial. "With both systems – aircraft signals as well as signals from shipping – we want to contribute to closing the gaps in location data," says Jörg Behrens of the DLR's Institute of Space Systems. If he's right, the key to keeping tabs on global air traffic could boil down to looking at it from above rather than from below.

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Benefits of sun 'may outweigh risks'

Benefits of sun 'may outweigh risks' | comagenius | Scoop.it

The health benefits of exposing skin to sunlight may far outweigh the risk of developing skin cancer, according to scientists.

Edinburgh University research suggests sunlight helps reduce blood pressure, cutting heart attack and stroke risks and even prolonging life.

UV rays were found to release a compound which lowers blood pressure.

Researchers said more studies would be carried out to determine if it is time to reconsider advice on skin exposure.

Heart disease and stroke linked to high blood pressure are estimated to lead to about 80-times more deaths than those from skin cancer in the UK.

Production of the pressure reducing compound, called nitric oxide, is separate from the body's manufacture of vitamin D, which rises after exposure to sunshine.

Researchers said that until now vitamin D had been thought to solely explain the sun's benefit to human health.

During the research, dermatologists studied the blood pressure of 24 volunteers under UV and heat lamps.

In one session, the volunteers were exposed to both the UV rays and the heat of the lamps.

In the other, the UV rays were blocked so that only the heat of the lamps affected the skin.

The results showed that blood pressure dropped significantly for one hour following exposure to UV rays, but not after the heat-only sessions.

Scientists said that this suggested it was the sun's UV rays that lead to health benefits.

The volunteers' vitamin D levels remained unaffected in both sessions.

'Reconsider our advice'

Dr Richard Weller, a senior lecturer in dermatology at Edinburgh University, said: "We suspect that the benefits to heart health of sunlight will outweigh the risk of skin cancer.

"The work we have done provides a mechanism that might account for this, and also explains why dietary vitamin D supplements alone will not be able to compensate for lack of sunlight.

"We now plan to look at the relative risks of heart disease and skin cancer in people who have received different amounts of sun exposure.

"If this confirms that sunlight reduces the death rate from all causes, we will need to reconsider our advice on sun exposure."

The study will be presented on Friday in Edinburgh at the world's largest gathering of skin experts. The International Investigative Dermatology conference starts on Wednesday and runs until Saturday.

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Postcognitive Topics: Dream in code: 'Neural Decoding of Visual Imagery During Sleep'

Postcognitive Topics: Dream in code: 'Neural Decoding of Visual Imagery During Sleep' | comagenius | Scoop.it
fMRI/EEG combination used to decode dream images

 A study recently published in the journal Science described work on dream image mapping carried out by neuroscientist Yukiyasu Kamitani and colleagues at the Advanced Telecommunications Research Computational Neuroscience labs in Kyoto, Japan.

 Functional magnetic resonance imaging (fMRI) was used to scan the brains of three young men as they drifted off to sleep inside an fMRI scanner, while simultaneously recording their brain activity using electroencephalography (EEG).

When the men had entered a ' hypnagogic state' - when their brain wave patterns had begun to resemble those known to be associated with sleep - they were woken up and asked to describe their dreams, then allowed to go back to sleep. This procedure was carried in three-hour blocks, repeated 7 to 10 times (on different days) for each volunteer. Approximately 200 dream reports were recorded from each participant, and the reported images were then grouped into categories that were specifically oriented  to the individual's particular patterns of  repeatedly-occurring elements using the lexical database WordNet. A video montage of images from the ImageNet database corresponding to the keywords generated by the dream reports was presented to the wide-awake men while their brain activity was being monitored. An algorithm developed to recognise the brain activity ''signatures'' associated with various dream images separated non-visual brain activity from vision-related excitation patterns, to verify that dreaming involves some of the same brain areas that are associated with visual imagery. This algorithm was combined with machine-learning techniques that used the waking brain activity patterns as 'training' examples. After training the program, the researchers input patterns of sleeping brain activity - the 'test' examples - and were able to predict which category of image had produced that pattern of brain activity.
Subsequently, upon awakening the dreamers in a second round of tests, the researchers were able to identify broad categories of dream images with 60 per cent accuracy.

''Our findings provide evidence that specific contents of visual experience during sleep are represented by, and can be read out from, visual cortical activity patterns shared with stimulus representation.''

 "By analysing the brain activity during the nine seconds before we woke the subjects, we could predict whether a man is in the dream or not, for instance, with an accuracy of 75–80%."

In 2008 Kamitani and his team had reported that they could decode and reconstruct visual images from brain activity in the primary visual cortical areas, where inputs from the retina are received. The present work looks at activity in the higher order brain regions that combine integration of the visual input with concept-level processes as well as information from other senses.

The  'hypnagogic state' is a state of consciousness between waking and sleeping. 'Embodied imagination' work on the hypnagogic state was pioneered by Robert Bosnak and based on principles first developed by Carl Jung. See International Journal of Dream Research Volume 4, Supplement 1 (2011)

Dreams in the hypnagogic state were studied rather than the dreams that occur during REM (rapid eye movement) sleep later in the night because it normally takes hours to transition to REM from normal sleep. Immobilisation inside an MRI tube until REM sleep is achieved, several times a day for 10 days, would be an ordeal.

Jack Gallant, a neuroscientist at the University of California, Berkeley, commented:

"In this field of dream decoding, no one has managed to successfully do this before. So this is not the final step down this road, it's the first step."

"If you could build the perfect dream decoder it would create a movie on your television screen and it would just replay your dreams. It would replay all the actions that happened, the actors, the people involved and it would replay the sound."



Horikawa, T., et al. (2013). Neural Decoding of Visual Imagery During Sleep. Science, doi: 10.1126/science.1234330)


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