Di seguito gli interventi pubblicati in questa sezione, in ordine cronologico.
A startup called TenKsolar, based in Minneapolis, says it can increase the amount of solar power generated on rooftops by 25 to 50 percent, and also reduce the overall cost of solar power by changing the way solar cells are wired together and adding inexpensive reflectors to gather more light.
TenKsolar says its systems can produce power for as little as eight cents a kilowatt-hour in sunny locations. That's significantly more expensive than electricity from typical coal or natural-gas power plants, but it is less than the average price of electricity in the United States.
Solar cells have become more efficient in recent years, but much of the improvement has gone to waste because of the way solar cells are put together in solar panels, the way the panels are wired together, and the way the electricity is converted into AC power for use in homes or on the grid. Typically, the power output from a string of solar cells is limited by the lowest-performing cell. So if a shadow falls on just one cell in a panel, the power output of the whole system drops dramatically. And failure at any point in the string can shut down the whole system.
Dark Mirror: Solar panels (with silver lines) are paired with reflectors (the solid dark material) to increase the amount of power a rooftop array can generate.
TenKsolar has opted for a more complex wiring system—inspired by a reliable type of computer memory known as RAID (for "redundant array of independent disks"), in which hard disks are connected in ways that maintain performance even if some fail. TenKsolar's design allows current to take many different paths through a solar-panel array, thus avoiding bottlenecks at low-performing cells and making it possible to extract far more of the electricity that the cells produce.
The wiring also makes it practical to attach reflectors to solar panels to gather more light. When solar panels are installed on flat roofs, they're typically mounted on racks that angle them toward the sun, and spaced apart to keep them from shading each other over the course of the day. Reflectors increase the amount of light that hits a solar array, but they reflect the sunlight unevenly. So in a conventional solar array, the output is limited by the cell receiving the least amount of reflected light. The new system can capture all the energy from the extra, reflected light. "The small added cost we put in on the electronics is paid back, plus a bunch, from the fact that we basically take in all of this reflected light," says Dallas Meyer, founder and president of TenKsolar. "We've architected a system that's completely redundant from the cell down to the inverter," he says. "If anything fails in the system, it basically has very low impact on the power production of the array."
The reflectors use a film made by 3M that reflects only selected wavelengths of light, reducing visible glare. The material also reflects less infrared light, which can overheat a solar panel and reduce its performance.
Meyer says the system costs about the same as those made by Chinese manufacturers but produces about 50 percent more power for a given roof area. Power output is about 25 percent higher than from the more expensive, high-performance systems made by SunPower, he says.
The new wiring approach does have a drawback: because it's new, the banks that finance solar-power installations may have doubts that the system will last for the duration of the warranty, and this could complicate financing, says Travis Bradford, an industry analyst and president of the Prometheus Institute for Sustainable Development.
TenKSolar, which has so far raised $11 million in venture funding and has the capacity to produce 10 to 12 megawatts of systems a year, is working on partnerships with larger companies to help provide financial backing for guarantees of its products.
Source: Technology Review
After weeks of dithering on the precipice of his own downfall, Silvio Berlusconi tonight survived a crucial vote of confidence, by one of the narrowest possible margins, allowing his government it to push through its proposed package of deeply unpopular austerity measures.
The cutbacks and tax hikes had been demanded by the European Central Bank in exchange for its buy-up of Italian bonds on secondary markets, after markets turned their sights on Italy last month, pushing the government’s borrowing costs close to the level where Greece had previously required an EU bailout.
But as Parliament prepared to vote on the austerity measures, violent clashes broke out between protesters and riot police. Downtown Rome was left billowing in smoke and littered with debris as at least 40 protesters were injured by random rounds of police baton charges.
“The police displayed a disproportionate reaction,” one witness told La Repubblica. “They were hit with batons, even women. A mother, too, was pushed and fell to the ground.” Images on Italian TV showed several people with bleeding head wounds and other injuries.
“And all this,” lamented Luca Cafagna of Unicommon, “because they are protesting against a move that is not shared, that will affect precarious young people, and that will not contribute to development. We need mass mobilizations in the fall,” he concluded, “especially in light of October 15th.”
On that day, mass demonstrations are scheduled to take place around the world to demand global change and an end to the oligarchy of financial elites and their political patrons. Take the Square, the international wing of the 15-M movement in Spain, has transformed itself into the digital hub of these worldwide events.
As the Italian crisis deepens, the people finally appear to be waking up from their deep slumber of political apathy. Tonight’s violence begs the question if Italy may soon be headed down the same road as Greece, where mass resistance to the austerity memorandum has made its implementation virtually impossible.
Either way, whatever happens in coming days and weeks, one thing has now become abundantly clear: the wave of protests and clashes that has been shaking the Mediterranean since the beginning of this year has finally reached the Italian shores. Things could start to get very serious very soon indeed.
Pictures of the clashes here, video here and here (embedding disabled)
“At the moment of the economic cataclysm,” Spitzer said — referring to the financial sector freeze-up that began in fall 2008 — “I thought, ‘We will finally have that epiphany that will bring us back, we will embrace rational policy once again.’ And here we are two years later, and I’m thinking: ‘What happened? How can this possibly be? Didn’t people learn a lesson?’ ... I’m afraid to say the answer is no, they didn’t.”
Speaking in a full Wong Auditorium, Spitzer suggested that Congress’ efforts at financial reform have not brought about substantive changes to the financial industry. That inertia has left the economy “on the precipice” and at risk of similar downturns in the future, Spitzer said, while maintaining a dangerous level of income inequality in the United States. The talk, “Government’s Place in the Market,” was part of a series of “Ideas Matter” forums, presented by Boston Review and the MIT Department of Political Science.
Three reasons for government to get involved
In his remarks, Spitzer outlined three main reasons why government is necessary to keep markets competitive and fair. First, he offered, “Only government can enforce rules of integrity, transparency and fair dealing in the marketplace. Private-sector companies simply can’t do it.” As an example, Spitzer cited his own experience as New York attorney general, prosecuting investment-bank analysts who promoted dot-com businesses, effectively helping the banks make money by underwriting initial public offerings of those firms’ stocks.
During the more recent collapsing bubble, tied to the collapse of the subprime-mortgage market, Spitzer noted that some investment banks were selling securities based on subprime mortgages to clients while privately betting that those securities would fall.
Second, normal economic actions produce “negative externalities,” or costs imposed on those not responsible for the activity, Spitzer observed. For instance, pollution from powerplants can move across state lines, creating health and economic costs for those far away from the source of pollution. “Only government can measure these negative externalities and try to impose behavior modification on the economic actors,” Spitzer said.
Finally, Spitzer noted, “There are certain core values that pure unbridled market behavior does not respond to,” naming discrimination laws as an example of necessary government interventions.
Spitzer served as New York attorney general from 1998 until 2006, then as governor from January 2007 until resigning a year later.
Moving the debate
In making the case for the active hand of government, Spitzer acknowledged, he was moving against a tide of “anti-government venom” over the last 30 years. That sentiment, Spitzer said, has successfully created a “shifting of the political debate far to the right” that helped undercut momentum for more ambitious reforms following the market meltdown of 2008-09.
Spitzer was introduced by Simon Johnson, the Ronald A. Kurtz (1954) Professor of Entrepreneurship at the MIT Sloan School of Management, who has also become a vocal critic of the banking industry. Johnson began the question-and-answer session after Spitzer's remarks with his own question: “What should any one individual do? … As a regular person, what opportunities do they have and what should they prioritize?”
In response, Spitzer said, “The first thing we should do is demand a greater level of integrity in the substantive answers we’re getting from our elected officials,” saying that members of both political parties have whitewashed the serious economic problems the country faces. In lieu of strengthening regulatory bodies such as the Securities and Exchange Commission, Spitzer said, “We need to reinvigorate shareholder activism.”
Spitzer has written a short book, also called Government’s Place in the Market, appearing this month as part of the Boston Review series published by MIT Press. This was the eighth and final “Ideas Matter” forum of the 2010-11 academic year. The event was taped for future airing on the cable network C-SPAN.
The first superlaser in the project is to be built near Prague, with a goal of achieving exawatt class, which would make it at least a hundred times more powerful than anything that exists today.
The purpose of the Extreme Light Infrastructure (ELI), as its known, is first and foremost to serve as a research tool. Such a laser could be used to develop new cancer diagnosis and treatments as well as possible ways to deal with nuclear waste. In addition, the simple existence and experimentation with such a powerful laser could expand knowledge of nanoscience and molecular biology.
The ELI project was not easily won, as there were five countries lobbying to have it in their home states, and thereafter there was some bit of contention among the commissioners regarding feasibility and financing of the project. With the win, though, the Czech Republic will be sit at the forefront of optic and photonic research, adding to its already impressive résumé; for the past ten years, Prague has hosted Precision Automated Laser Signals (PALS), one of the premier laser systems in all of Europe. The installation will signal another milestone as well; the ELI venture will be the first big research project funded by the EU that will be located in an Eastern European country.
Slated to become operational by 2015, and located in Dolní B?ežany, near Prague, the superlaser will operate using super-short pulses of very high energy particle and radiation beams, with each pulse lasting just 1.5 x 10-14 of a second, more than enough time to conduct high energy research experiments.
The installation in Prague will be followed up by projects in Hungary and then Romania, with each specializing in different areas of research; all of which will culminate in the development of a fourth super-super laser in an as yet to be decided location, which is expected to have twice the power of the original three lasers (though current plans have it comprised of 10 beans) which should add up to 200 petawatts of power; the theoretical limit for lasers.
The project is expected to cost in the neighborhood of €700 million.
Developed by an interdisciplinary team at the University of Alberta and Canada's National Institute for Nanotechnology, this new process was developed to address some of the problems associated with the introduction of stainless steel into the human body.
Implanted biomedical devices, such as cardiac stents, are implanted in over 2 million people every year, with the majority made from stainless steel. Stainless steel has many benefits -- strength, generally stability, and the ability to maintain the required shape long after it has been implanted. But, it can also cause severe problems, including blood clotting if implanted in an artery, or an allergenic response due to release of metal ions such as nickel ions.
The University of Alberta campus is home to a highly multidisciplinary group of researchers, the CIHR Team in for Glyconanotechnology in Transplantation, that is looking to develop new synthetic nanomaterials that modify the body's immune response before an organ transplant. The ultimate goal is to allow cross-blood type organ transplants, meaning that blood types would not necessarily need to be matched between donor and recipient when an organ becomes available for transplantation. Developing new nanomaterials that engage and interact with the body's immune system are an important step in the process. In order to overcome the complex range of requirements and issues, the project team drew on expertise from three major areas: surface science chemistry and engineering, carbohydrate chemistry, and immunology and medicine.
For the transplantation goals of the project, sophisticated carbohydrate (sugar) molecules needed to be attached to the stainless steel surface to bring about the necessary interaction with the body's immune system. Its inherent stainless characteristic makes stainless steel a difficult material to augment with new functions, particularly with the controlled and close-to-perfect coverage needed for biomedical implants. The Edmonton-based team found that by first coating the surface of the stainless steel with a very thin layer (60 atoms deep) of glass silica using a technique available at the National Institute for Nanotechnology, called Atomic Layer Deposition (ALD), they could overcome the inherent non-reactivity of the stainless steel. The silica provide a well-defined "chemical handle" through which the carbohydrate molecules, prepared in the Alberta Ingenuity Centre for Carbohydrate Science, could be attached. Once the stainless steel had been controlled, the researchers demonstrated that the carbohydrate molecules covered the stainless steel in a highly controlled way, and in the correct orientation to interact with the immune system.
Source: Science Daily
It seems it might be something as mundane as adding in the tiny forces that occur when minute traces of heat from the plutonium on board the probes bounce off their receiving dishes, creating a counterforce, which in turn, causes the craft to slow; if ever so slightly.
The Pioneer anomaly, as it’s come to be known, has had physicists scratching their heads ever since an astronomer by the name of John Anderson, working for NASA’s Jet Propulsion Laboratory, back in 1980, noticed a discrepancy between the slowdown rate projections for the craft and the rates they were actually experiencing, which led to the basic question, how could both probes be slowing down faster than the laws of physics projected? Possible explanations ranged from unknown mechanical issues with both craft, to dark matter pushing back, to possible flaws in the physics theories themselves.
But now, Frederico Francisco of the Instituto de Plasmas e Fusao Nuclear, Lisbon Portugal and colleagues, as they describe in their paper published inarXiv, seem to have solved the problem using a simple old technology.
Schematics of the conﬁguration of Lambertian sources used to model the lateral walls of the main equipment compartment.
Suspecting that heat was involved, they started with follow-up work by Anderson in 2002 and Slava Turyshev in 2006, also from NASA’s Jet Propulsion Laboratories, who both showed that heat released from the plutonium onboard the spacecraft could very well explain a slowdown. Unfortunately, both concluded that such heat emissions could not possibly account for the amount of slowdown seen. But this was because neither man thought to consider the impact of heat hitting the backside of the satellite dish (antennae) and then bouncing back. Francisco and his team used a computer modeling technique called Phong shading to show how the flow of heat as it was emitted from the main equipment compartment could emanate outwards, eventually bouncing off the back of the dish, resulting in just enough counterforce to explain the gravitational discrepancy.
Case closed, as far as Francisco et al are concerned, but of course this being science, others will have to replicate the results before any sort of consensus can be found.
Roughly 7,000 rural communities in the U.S. deal with sewage the old-fashioned way: by dumping it into an open holding pond and letting sunlight and bacteria do the rest. Not only do these ponds smell bad, but it takes the bacteria a long time to render the sewage nonhazardous, a situation that could pose a contamination risk to waterways.
Poo Lagoon - These "Poo-Gloos," which normally rest on the bottom of a wastewater pond, await installation. Bacteria living in the domes break down contaminates into compounds such as carbon dioxide. Aerators within them keep oxygen flowing to the microbes. Wastewater Compliance Systems.
Wastewater-treatment plants, the most common solution, cost upward of $2 million to build, according to Kraig Johnson, the chief technology officer of Salt Lake City–based Wastewater Compliance Systems. Johnson, who researched biological solutions for sewage treatment at the University of Utah, is pilot-testing a simple and cheap solution: BioDomes, which house bacteria that break down contaminants in sewage.
So far, 200 BioDomes (colloquially known as Poo-Gloos) are cleaning up sewage in six states, including Alabama and Nevada, and early data suggests that they might be as efficient as mechanical wastewater-treatment plants.
Air capture, in which carbon dioxide is removed from the atmosphere, has been touted as a potentially promising way to tackle climate change. That's because unlike carbon capture from power plant flue gases, the technology has the potential to reduce existing CO2 levels, rather than simply slowing the rate of increase.
To demonstrate that the technology works, Christopher Jones at the Georgia Institute of Technology in Atlanta tested a CO2 absorbent based on amines - the chemicals predominantly used in power plant carbon capture trials - on gases with CO2 concentrations similar to those found in ambient air.
He found the material was able to repeatedly extract CO2 from the gas without being degraded, which will be vital if the technology is to be used economically on a wide-scale.
However, unlike the liquid amines typically used in power plant carbon capture, which consume large amounts of energy as they must be heated to very high temperatures to re-release their stored CO2, Jones' team has developed a new class of the material called hyperbranched aminosilica, in which the amine is held on a solid porous silica substrate.
Solid amines release the stored CO2 when heated to just 110 degrees Celsius - much lower than the temperatures required by the water-based liquid amine solutions - reducing the amount of energy required by 75 per cent.
This also means the energy needed could be supplied by widely available sources such as waste heat from industrial plants, says Peter Eisenberger of air capture company Global Thermostat, based in New York. The energy could also be supplied by renewable sources such as solar power, he says. The captured CO2 could then be fed to algae, which absorb the gas to produce biofuel and biochar.
Jones is working with the company to test a pilot air capture plant in Menlo Park, California, which is absorbing 2 tonnes of CO2 from the atmosphere each day. A commercial plant could absorb 1 million tonnes of CO2 per day, says Eisenberger.
Chenglong Li, Ph.D., an assistant professor of medicinal chemistry and pharmacognosy at The Ohio State University (OSU), is leveraging a powerful computer cluster at the Ohio Supercomputer Center (OSC) to develop a drug that will block the small protein molecule Interleukin-6 (IL-6). The body normally produces this immune-response messenger to combat infections, burns, traumatic injuries, etc. Scientists have found, however, that in people who have cancer, the body fails to turn off the response and overproduces IL-6.
"There is an inherent connection between inflammation and cancer," explained Li. "In the case of breast cancers, a medical review systematically tabulated IL-6 levels in various categories of cancer patients, all showing that IL-6 levels elevated up to 40-fold, especially in later stages, metastatic cases and recurrent cases."
In 2002, Japanese researchers found that a natural, non-toxic molecule created by marine bacteria -- madindoline A (MDL-A) -- could be used to mildly suppress the IL-6 signal. Unfortunately, the researchers also found the molecule wouldn't bind strongly enough to be effective as a cancer drug and would be too difficult and expensive to synthesize commercially. And, most surprisingly, they found the bacteria soon mutated to produce a different, totally ineffectual compound. Around the same time, Stanford scientists were able to construct a static image of the crystal structure of IL-6 and two additional proteins.
An electrostatic representation (red: negative; blue: positive; white: hydrophobic) created at the Ohio Supercomputer Center by Ohio State’s Chenglong Li, Ph.D., shows IL-6 in ribbon representation. The two larger yellow ellipses indicate the two binding "hot spots" between IL-6 and GP130, key to blocking a protein that plays a role in breast and prostate cancer. (Credit: Chenglong Li/OSU)
Li recognized the potential of these initial insights and partnered last year with an organic chemist and a cancer biologist at OSU's James Cancer Hospital to further investigate, using an OSC supercomputer to construct malleable, three-dimensional color simulations of the protein complex.
"The proximity of two outstanding research organizations -- the James Cancer Hospital and OSC -- provide a potent enticement for top medical investigators, such as Dr. Li, to conduct their vital computational research programs at Ohio State University," said Ashok Krishnamurthy, interim co-executive director of OSC.
"We proposed using computational intelligence to re-engineer a new set of compounds that not only preserve the original properties, but also would be more potent and efficient," Li said. "Our initial feasibility study pointed to compounds with a high potential to be developed into a non-toxic, orally available drug."
Li accessed 64 nodes of OSC's Glenn IBM 1350 Opteron cluster to simulate IL-6 and the two additional helper proteins needed to convey the signal: the receptor IL-6R and the common signal-transducing receptor GP130. Two full sets of the three proteins combine to form a six-sided molecular machine, or "hexamer," that transmits the signals that will, in time, cause cellular inflammation and, potentially, cancer.
Li employed the AMBER (Assisted Model Building with Energy Refinement) and AutoDock molecular modeling simulation software packages to help define the interactions between those proteins and the strength of their binding at five "hot spots" found in each half of the IL-6/IL-6R/GP130 hexamer.
By plugging small molecules, like MDL-A, into any of those hot spots, Li could block the hexamer from forming. So, he examined the binding strength of MDL-A at each of the hexamer hotspots, identifying most promising location, which turned out to be between IL-6 and the first segment, or modular domain (D1), of the GP130.
To design a derivative of MDL-A that would dock with D1 at that specific hot spot, Li used the CombiGlide screening program to search through more than 6,000 drug fragments. So far, he has identified two potential solutions by combining the "top" half of the MDL-A molecule with the "bottom" half of a benzyl molecule or a pyrazole molecule. These candidates preserve the important binding features of the MDL-A, while yielding molecules with strong molecular bindings that also are easier to synthesize than the original MDL-A.
"While we didn't promise to have a drug fully developed within the two years of the project, we're making excellent progress," said Li. "The current research offers us an exciting new therapeutic paradigm: targeting tumor microenvironment and inhibiting tumor stem cell renewal, leading to a really effective way to overcome breast tumor drug resistance, inhibiting tumor metastasis and stopping tumor recurrence."
While not yet effective enough to be considered a viable drug, laboratory tests on tissue samples have verified the higher potency of the derivatives over the original MDL-A. Team members are preparing for more sophisticated testing in a lengthy and carefully monitored evaluation process.
Li's project is funded by a grant from the Department of Defense (CDMRP grant number BC095473) and supported by the award of an OSC Discovery Account. The largest funding areas of Congressionally Directed Medical Research Programs (CDMRP) are breast cancer, prostate cancer and ovarian cancer. Another Defense CDMRP grant involving Li supports a concurrent OSU investigation of the similar role that IL-6 plays in causing prostate cancer. Those projects are being conducted in collaboration with Li's Medicinal Chemistry colleague, Dr. James Fuchs, as well as Drs. Tushar Patel, Greg Lesinski and Don Benson at OSU's College of Medicine and James Cancer Hospital, and Dr. Jiayuh Lin at Nationwide Children's Hospital in Columbus.
"In addition to leading the center's user group this year, the number and depth of Dr. Li's computational chemistry projects have ranked him one of our most prolific research clients," Krishnamurthy noted.
Source: Science Daily
This new particle, also known as the anti-alpha, is the heaviest antinucleus ever detected, topping a discovery announced by the same collaboration just last year.
The new record will likely stand far longer, the scientists say, because the next weightier antimatter nucleus that does not undergo radioactive decay is predicted to be a million times more rare - and out of reach of today's technology.
"This discovery highlights the extraordinary capabilities of RHIC to investigate fundamental questions about the nature of matter, antimatter, and the early universe," said William F. Brinkman, Director of the DOE Office of Science.
Steven Vigdor, Brookhaven's Associate Lab Director for Nuclear and Particle Physics, who leads the RHIC program, said, "Barring a new breakthrough in accelerator technology, or the discovery of a completely new production mechanism, it is likely that antihelium-4 will remain the heaviest stable antimatter nucleus observed for the foreseeable future."
The STAR physicists describe the discovery in a paper in Nature, published online April 24, 2011.
The ability to create and study antimatter in conditions similar to those of theearly universe is no small matter: One of the great mysteries of physics is why our universe appears to be made entirely of ordinary matter when matter and antimatter are understood to have been created in equal amounts at the time of the Big Bang.
At RHIC, head-on collisions of gold ions moving at nearly the speed of light simulate conditions just after the Big Bang. In these atomic smashups, quarks and antiquarks likewise emerge with approximately equal abundance. A major fraction of the stable antimatter produced in RHIC collisions leaves a clear signal in the STAR detector before annihilating with ordinary matter in the outer part of the experimental apparatus.
By sifting through data for half a trillion charged particles emitted from almost one billion collisions, the STAR collaboration has detected 18 examples of the unique "signature" of the antihelium-4 nucleus. Consisting of two antiprotons and two antineutrons in a stable bound state that does not undergo radioactive decay, the antihelium-4 nucleus has a negative electric charge that is twice that of an electron, while its mass is very close to four times that of a proton. Data plots show that the newly discovered anti-alphas are very cleanly separated from the lighter isotopes, and are at the expected mass.
The scientists also measured the antihelium-4 production rate in nuclear interactions, and found that it is consistent with expectations based on a statistical coalescence of antiquarks from the soup of quarks and antiquarks generated in RHIC collisions. But the fact that 12 antiquarks combine to build such a complex antinucleus in a way that bears out these predictions is really quite remarkable considering it all takes place in the midst of rapidly expanding matter created at trillions of degrees and surviving for only ten trillionths of a trillionth of a second.
Knowing the production rate of these antinuclei is important to a wide range of scientific disciplines, including searches for new phenomena in the cosmos. For example, it ties in with the scientific goals of an experiment known as the Alpha Magnetic Spectrometer (AMS), which will be delivered to the International Space Station via one of the last space shuttle missions, currently scheduled for launch in late April 2011. This experiment will search for antimatter in space.
"If AMS were to find evidence for the existence of bulk antimatter elsewhere in the cosmos, the new measurement from the STAR experiment would provide the quantitative background rate for comparison," said Hank Crawford, a STAR collaborator from the University of California, Berkeley, Space Sciences Laboratory. "An observation of antihelium-4 by the AMS experiment could indicate the existence of large quantities of antimatter somehow segregated from the matter in our universe," he said.
In 2010, the Large Hadron Collider at CERN, the European laboratory for nuclear and particle physics research, began its own collisions of heavy nuclei at energies more than an order of magnitude higher than at RHIC. Experiments there also have the capability to study production of antinuclei, and it will be interesting to see what those experiments find at higher energies.
"The discovery of the antihelium-4 nucleus also has special synergy with a major scientific anniversary: the 100th anniversary of Ernest Rutherford's seminal gold foil experiments, in which he used ordinary-matter helium-4 (alpha) particles to probe the structure of matter," said Brookhaven physicist Aihong Tang, a member of the STAR collaboration and a lead author on the Nature paper. "These experiments, conducted in 1911, established the very existence of atomic nuclei for the first time, and marked the dawn of our modern understanding of atoms."