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Archives for : febbraio2014

SunPower Continues to Drive Down the Cost Curve

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SunPower Continues to Drive Down the Cost Curve
http://www.greentechmedia.com/articles/read/SunPower-Continues-To-Drive-Down-the-Cost-Curve

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Researchers propose a better way to make sense of ‘Big Data’

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Two researchers at Cold Spring Harbor Laboratory challenge the most recent advances in this Big Data analysis, using a classic mathematical concept to tackle the outstanding problems in this field. Mutual information is able to uncover patterns in large lists of numbers, revealing entirely new, unexpected patterns.

Big Data is everywhere, and we are constantly told that it holds the answers to almost any problem we want to solve. Companies collect information on how we shop, doctors and insurance companies gather our medical test results, and governments compile logs of our phone calls and emails. In each instance, the hope is that critical insights are hidden deep within massive amounts of information, just waiting to be discovered.

But simply having lots of data is not the same as understanding it. Increasingly, new mathematical tools are needed to extract meaning from enormous data sets. In work published online today, two researchers at Cold Spring Harbor Laboratory (CSHL) now challenge the most recent advances in this field, using a classic mathematical concept to tackle the outstanding problems in Big Data analysis.

What does it mean to analyze Big Data? A major goal is to find patterns between seemingly unrelated quantities, such as income and cancer rates. Many of the most common statistical tools are only able to detect patterns if the researcher has some expectation about the relationship between the quantities. Part of the lure of Big Data is that it may reveal entirely new, unexpected patterns. Therefore, scientists and researchers have worked to develop statistical methods that will uncover these novel relationships.

In 2011, a distinguished group of researchers from Harvard University published a highly influential paper in the journal Science that advanced just such a tool. But in a paper published today in Proceedings of the National Academy of Sciences, CSHL Quantitative Biology Fellow Justin Kinney and CSHL Assistant Professor Gurinder “Mickey” Atwal demonstrate that this new tool is critically flawed. “Their statistical tool does not have the mathematical properties that were claimed,” says Kinney.

Kinney and Atwal show that the correct tool was hiding in plain sight all along. The solution, they say, is a well known mathematical measure called “mutual information,” first described in 1948. It was initially used to quantify the amount of information that could be transmitted electronically through a telephone cable; the concept now underlies the design of the world’s telecommunications infrastructure. “What we’ve found in our work is that this same concept can also be used to find patterns in data,” Kinney explains. “This beautiful mathematical concept has the potential to greatly benefit modern data analysis, in biology and in biology and many other important fields.


See on phys.org

A synchronized global sweep of the internal genes of modern avian influenza virus : Nature : Nature Publishing Group

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Zoonotic infectious diseases such as influenza continue to pose a grave threat to human health. However, the factors that mediate the emergence of RNA viruses such as influenza[thinsp]A virus (IAV) are still incompletely understood. Phylogenetic inference is crucial to reconstructing the origins and tracing the flow of IAV within and between hosts. Here we show that explicitly allowing IAV host lineages to have independent rates of molecular evolution is necessary for reliable phylogenetic inference of IAV and that methods that do not do so, including /`relaxed/’ molecular clock models, can be positively misleading. A phylogenomic analysis using a host-specific local clock model recovers extremely consistent evolutionary histories across all genomic segments and demonstrates that the equine H7N7 lineage is a sister clade to strains from birds[mdash]as well as those from humans, swine and the equine H3N8 lineage[mdash]sharing an ancestor with them in the mid to late 1800s. Moreover, major western and eastern hemisphere avian influenza lineages inferred for each gene coalesce in the late 1800s. On the basis of these phylogenies and the synchrony of these key nodes, we infer that the internal genes of avian influenza virus (AIV) underwent a global selective sweep beginning in the late 1800s, a process that continued throughout the twentieth century and up to the present. The resulting western hemispheric AIV lineage subsequently contributed most of the genomic segments to the 1918 pandemic virus and, independently, the 1963 equine H3N8 panzootic lineage. This approach provides a clear resolution of evolutionary patterns and processes in IAV, including the flow of viral genes and genomes within and between host lineages.


See on www.nature.com

Miniaturized hearing aids that will fit into the ear canal

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Fraunhofer researchers pack a total of 19 hearing-aid components (left) into their new microsystem (right). System-on-chip integrated circuit, high-frequency

 

The technology is also suitable for implants, pacemakers, and insulin pumps. This all means that the system uses only a fraction of the energy required by conventional devices, keeping cumbersome battery changes to a minimum. “Ideally, patients should not even be feeling of wearing the hearing aid over long periods of time,” says Dr. Dionysios Manessis from Fraunhofer Institute of Reliability and Microintegration IZM in Berlin.

With dimensions of just 4 mm by 4mm by 1 mm, the new microsystem is fifty times smaller than the current models. To achieve this, the project partners first developed especially small components such as innovative miniature antennas, system-on-chip integrated circuitry and high frequency filters, then integrated the 19 discrete components in a single module, using a modular 3D stacking concept that saves extra space.

Hearing aids worn behind the ear are powered by a 180mAh  (milliampere hour) battery, which must be either replaced or recharged approximately every two weeks. The aim is to minimize the system’s energy consumption to around one milliwatt (mW) to extend battery life up to 20 weeks.

The development is part of the EU WiserBAN project. Project partners are also looking to optimize energy management. The WiserBAN project partners are also developing special antenna and wireless protocols that can communicate information such as pulse, blood pressure, or glucose levels straight to a physician’s tablet or smartphone. The resulting WiserBAN wireless system makes obsolete the relay station — an extra device that patients have previously been obliged to wear to extend the communication range.

Another advantage is that the wireless protocols developed within the WiserBAN project are based on the reliable IEEE 802.15.4 and 802.15.6 standards. Conventional devices have ordinarily relied on Bluetooth, where there are often issues with interference with other devices.

It is hoped that the new technology will act as the springboard for more comfortable, more reliable healthcare products in the future — from long-term electrocardiography to insulin pumps. Furthermore, there is the potential to use the microsystem in implants and pacemakers.


See on www.kurzweilai.net

Clean Energy Can Provide Jobs And Security

A new report from the International Renewable Energy Agency (IRENA) says the renewable energy industry is responsible for 615,000 jobs in the United States. That’s hundreds of thousands of Americans working to provide this country with clean energy from wind, sun and plants. It’s the military vet in Kansas putting her hydraulics knowledge to work in her new job servicing 300-foot-tall wind turbines. It’s the former glass maker in Toledo, Ohio, who’s now manufacturing solar panels. It’s the farmer who’s got a new buyer in the biofuel plant just across the county line. It’s engineers and managers and truckers and technicians in nearly every state in the nation.

Renewable energy development is making a difference in this country, bringing sorely needed jobs and revenue to communities, while protecting clean air and clean water. Clean, renewable energy is working for us. That’s why so many Americans, from all political stripes, want to see more of it.

A recent national poll found that voters preferred investing in clean energy and efficiency over traditional fossil fuel energy by a margin of nearly 2-to-1. In Kansas, arecent poll found overwhelming support for clean, renewable energy and the government policies that encourage its growth. Roughly three-quarters of Republicans and Independents, and 82 percent of Democrats, support the state’s Renewable Portfolio Standard, which requires that utilities generate 20 percent of their energy from renewable sources by 2020. In fact, two-thirds of voters said they would support increasing the state’s standard to 25 percent. Nine out of ten poll respondents believed that using renewable energy is the right thing to do for the future of Kansas and the country.

image via Shutterstock

image via Shutterstock

Communities in Kansas are not alone in reaping the benefits of clean, renewable energy. According to preliminary analysis from Environmental Entrepreneurs (E2), more than 78,600 clean energy and clean transportation jobs were announced across the country in 2013. Over the past two years combined, E2 has tracked announcements that could create more than 186,500 jobs.

Federal tax policies–such as the production tax credit (PTC) for wind energy, as well as energy efficiency tax incentives for buildings, equipment and appliances— are saving money and creating tens of thousands of jobs while also reducing dangerous carbon pollution that causes climate change and health problems. Congress allowed clean energy tax credits to expire last year: it needs to renew them.

In addition to creating thousands of jobs in the wind energy industry alone, clean energy tax credits save billions of dollars for taxpayers by helping make our homes, schools and office buildings more efficient, and making everyday appliances and equipment use less energy. Energy efficiency, of course, is the cleanest energy of all—there’s nothing cleaner than the energy we don’t use—and it drives job growth as well. In Ohio, for example, utility efficiency efforts alone have created 3,800 jobs , and are expected to create 32,000 jobs by 2025. Federal energy efficiency standards for appliances have generated 340,000 jobs as of 2010, according to the American Council for an Energy Efficient Economy.

Clean energy is one of those issues that we can all rally around. We all want to breathe clean air and drink clean water. We all want to keep the lights on. We’d all like to avoid a future of more frequent, costly extreme weather, from crippling snowstorms in the South, and exhausting drought in the West, to dangerous hurricanes in the East and deadly floods in the Midwest. And we want a strong economy with good jobs, too.

Americans are looking to clean renewable energy because it provides so many of the solutions people are looking for—jobs, environmental protection, reliability, security. With the right policies in place to support the growth of renewable energy, we can continue to move toward a future of 100 percent clean energy.

Editor’s Note: EarthTechling is proud repost this article courtesy of Natural Resources Defense Council . Author credit goes to Peter Lehner .

New application of physics tools used in biology

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A Lawrence Livermore National Laboratory physicist and his colleagues have found a new application for the tools and mathematics typically used in physics to help solve problems in biology.


See on www.llnl.gov

What is the Future for Genetic Testing and Personalized Medicine?

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Personalized medicine, or the ability for the medical profession to tailor therapy to particular individuals’ genetic characteristics, has been a long desired but ever elusive goal for the life sciences.  However, the prospects for personalized medicine appear to be improving in recent years.  These changes come in the wake of a variety of medical advances, including human genomic testing and cancer drugs targeted for individuals with specific genetic profiles.

 

As public attention to understanding the human genome has increased, the topic has garnered substantial controversy and regulation in this sector is poised to increase.  The Food and Drug Administration (FDA) has already indicated its intent to regulate—most recently in a report clarifying its future role in personalized medicine and in warning letters to direct-to-consumer genetic testing companies.

 

The FDA maintains it has the authority to regulate personal genetic data because it defines that data as a medical device under Section 201(h) of the Food Drug & Cosmetics Act.  The agency also points to its role as the federal body charged with providing guidance on medical device claims and protecting consumers.

 

Some health scholars and consumers have weighed in on the propriety of regulation.  In a study of consumer attitudes toward regulating direct-to-consumer genetic testing, researchers found many consumers wanted unfettered access to genetics testing services without government regulation, but favored oversight to ensure that the information provided was high quality.

 
See on www.regblog.org

Direct measurements of the wave nature of matter, previously only known from theory

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At the heart of quantum mechanics is the wave-particle duality: matter and light possess both wave-like and particle-like attributes. Typically, the wave-like properties are inferred indirectly from the behavior of many electrons or photons, though it’s sometimes possible to study them directly. However, there are fundamental limitations to those experiments—namely information about the wave properties of matter that is inherently inaccessible.

 

And therein lies a loophole: two groups used indirect experiments to reconstruct the wave structure of electrons. A.S. Stodolna and colleagues manipulated hydrogen atoms to measure their electron’s wave structure, validating more than 30 years of theoretical work on the phenomenon known as the Stark effect. A second experiment by Daniel Lüftner and collaborators reconstructed the electronic structure of individual organic molecules through repeated scanning, with each step providing a higher resolution. In both cases, the researchers were able to match theoretical predictions to their results, verifying some previously challenging aspects of quantum mechanics.

 

Neither a wave nor a particle description can describe all experimental results obtained by physicists. Photons interfere with each other and themselves like waves when they pass through openings in a barrier, yet they show up as individual points of light on a phosphorescent screen. Electrons create orbital patterns inside atoms described by three-dimensional waves, yet they undergo collisions as if they were particles. Certain experiments are able to reconstruct the distribution of electric charge inside materials, which appears very wave-like, yet the atoms look like discrete bodies in those same experiments.

 

The wave functions in the Stark effect have a peculiar mathematical property, one which Stodolna and colleagues recreated in the lab. They separated individual hydrogen atoms from hydrogen sulfide (H2S) molecules, then subjected them to a series of laser pulses to induce specific energy transitions inside the atoms. By measuring the ways the light scattered, the researchers were able to recreate the predicted wave functions—the first time this has been accomplished. The authors also argued that this method, known as photoionization microscopy, could be used to reconstruct wavefunctions for other atoms and molecules.

Lüftner and colleagues took a different approach and examined the wave functions of organic molecules chemically attached (adsorbed) on a silver surface. Specifically, they looked at pentacene (C22H14) and the easy-to-remember compound perylene-3,4,9,10-tetracboxylic dianhydride (or PTCDA, C24H8O6). Unlike hydrogen, the wave functions for these molecules cannot be calculated exactly. They usually require using “ab initio” computer models.

 

The researchers were particularly interested in finding the phase, that bit of the wave function that can’t be measured directly. They determined that they could reconstruct it by using the particular way the molecules bonded to the surface, which enhanced their response to photons of a specific wavelength. The experiment involved taking successive iterative measurements by exciting the molecules using light, then measuring the angles at which the photons were scattered away.

 

Reconstructing the phase of the wave function required exploiting the particular mathematical form it took in this system. Specifically, the waves had a relatively sharp edge, allowing the researchers to make an initial guess and then refine the value as they took successive measurements. Even with this sophisticated process, they were only able to determine the phase to an arbitrary precision—something entirely to be expected from fundamental quantum principles. However, they were able to experimentally reconstruct the entire wave function of a molecule. There was previously no way to check whether our calculated wave functions were accurate or not.

 

REFERENCES:

Physical Review Letters, 2013. DOI: 10.1103/PhysRevLett.110.213001 and
PNAS, 2013. DOI: 10.1073/pnas.1315716110  (About DOIs).


See on arstechnica.com

Bose-Einstein Condensate Made at Room Temperature for First Time

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The quantum mechanical phenomena, known as Bose-Einstein Condensate (BEC), was first demonstrated in 1995 when experiments proved that the septuagenarian theory did in fact exist in the physical world. Of course, to achieve the phenomena a state of near absolute zero (-273 Celsius, -459 Fahrenheit) had to be created.

 

Now researchers at IBM’s Binnig and Rohrer Nano Center have been able to achieve the BEC at room temperature using a specially developed polymer, a laser, and some mirrors.

 

IBM believes that this experiment could potentially be used in the development of novel optoelectronic devices, including energy-efficient lasers and ultra-fast optical switches. One application for BEC is for the building of so-called atom lasers, which could have applications ranging from atomic-scale lithography to measurement and detection of gravitational fields.

 

For the first time, the IBM team achieved it at room temperature by placing a thin polymer film—only 35 nanometers thick—between two mirrors and then shining a laser into the configuration. The bosonic particles are created as the light travels through the polymer film and bounces back and forth between the two mirrors.

 

While this BEC state of matter only lasts for a few picoseconds (trillionths of a second), the IBM researchers believe that it exists long enough to create a source of laser-like light or an optical switch that could be used in optical interconnects.

 

“That BEC would be possible using a polymer film instead of the usual ultra-pure crystals defied our expectations,” said Dr. Thilo Stöferle, a physicist, at IBM Research, in a press release. “It’s really a beautiful example of quantum mechanics where one can directly see the quantum world on a macroscopic scale.”

 

Now that the researchers have managed to trigger the effect, they are now looking to gain more control over it. In the process they will be evaluating how the effect could best be exploited for a range of applications. One interesting application that will be examined is using the BEC in analog quantum simulations for such macroscopic quantum phenomena as superconductivity, which is extremely difficult to model with today’s simulation approaches.


See on spectrum.ieee.org

How to flip the switch on HIV-related cancer

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Researchers have identified a critical component in the virus that causes Kaposi’s sarcoma, the most common cancer among people infected with HIV.

In this study, which appears in the peer-reviewed journal PLOS Pathogens, the team identified a cluster of viral microRNA molecules that are necessary to transform healthy cells into cancerous ones. When this microRNA cluster was suppressed, the cells died after they were infected with KSHV.

Flipping the switch and turning the cluster back “on,” however, allowed the cells to stay alive and become malignant when infected with the virus.

Using advanced genomic methods, the researchers also found that the microRNAs target the IκBα protein and the NF-κB cellular pathway, both of which are associated with cancer development.


See on www.futurity.org

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