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Earlier this year, juniors Eric Berdinis and Jeff Kiske, both computer engineering majors in the School of Engineering and Applied Science, hacked together a high-tech upgrade for the visually impaired out of off-the-shelf video game equipment. Called the Kinecthesia, it’s a belt-worn camera system that gives users feedback about their immediate surroundings through directional vibrations.

Although it’s fresh out of the workshop, the Kinecthesia is already generating buzz: it was selected as one of 10 projects for Google’s Zeitgeist Young Minds conference, which highlights college-aged innovators.

Berdinis and Kiske started the project as their final assignment in professor Rahul Mangharam’s embedded systems class. Tasked with creating a medical device, the duo began exploring the Microsoft Kinect, a video game controller that uses multiple cameras to translate a player’s real-life motions into actions on the screen.

“We saw that there wasn’t much in the way of assistive devices that had to do with vision, despite all of these new cameras and things like the Kinect,“ says Kiske. “We just thought it looked cool and started playing around with it.”

Recognizing the Kinect’s ability to translate details about environmental depth into digital information as a route to a high-tech upgrade on walking canes, the team began figuring out how to integrate the technology into a wearable device. Getting the cameras to talk to the BeagleBoard, a miniature, customizable computer at the heart of the system, was the first step.

 

“The Kinect wasn’t intended to work with anything but the Xbox, so modifying the code to make it work on this processor was one of the biggest challenges,” says Berdinis.

Though the Kinect is great at determining how far away objects are, another challenge was deciding how to relay that information to the user.

“We didn’t want to overwhelm the user with audio cues or vibration motors all across the waist,” says Berdinis. “Through trial and error, we found that three buzzer zones was the right amount.”

The three buzzers, positioned left, right and center, begin vibrating once objects become close enough to potentially impede the user, and increase in intensity as the objects get closer.

Berdinis and Kiske will continue to work on the Kinecthesia; connections made through the Google conference have enabled them to work with the visually impaired community and further refine their system into what could be a life-changing product.

Source: PhysOrg

More information: http://www.kinecthesia.com/

Provided by University of Pennsylvania - via ZeitNews.org

 

Spurred by a wave of recent Web videos showing the bottom of a dropped  hovering dramatically in midair , physicists have provided new insights into this phenomenon, from the existence of shock waves in the falling Slinky, to a remarkably universal "levitation" time for a Slinky on other planets or moons despite their different gravitational fields.

In February 2000, the late science writer Martin Gardner posed a simple question intended for physics students, but also triggering a new round of papers and videos on the much-studied toy. Gardner wrote: "If you hold one end of a Slinky, letting it hang down and then drop it, what happens?"

"It turns out the bottom stays suspended, levitating in air for some period in time," said Shimon Kolkowitz, a physics graduate student at Harvard University in Cambridge, Mass. As an undergraduate at Stanford University in Palo Alto, Calif. in 2007, Kolkowitz wrote a paper now posted online for a class taught by his professor, physics Nobel Laureate Robert Laughlin.

And recently, Bill Unruh, a physics professor at the University of British Columbia, in Vancouver, heard some colleagues in the faculty lounge discussing a video of the levitating Slinky. As a result, Unruh, a world expert in black hole radiation, became captivated with Slinky physics.

Making calculations over a couple of days, Unruh wrote and posted a paper on the falling Slinky at the website arXiv.

Inspired by Gardner's riddle and earlier Slinky studies while putting together his paper, Kolkowitz calculated that the bottom of his metal Slinky would remain suspended for approximately three-tenths of a second. And only recently he made a surprising realization: the levitation time of the toy would be exactly the same if it were dropped on the moon, Jupiter or Mars, even with their vastly different gravitational fields.

Unruh found that the falling Slinky creates a shock wave through the toy, analogous to the blast wave of a bomb or a sonic boom created by aircraft.

What in the world is going on?

"A Slinky is a simple spring, with the unique attribute that the spring in its natural resting state has all the coils touching one another," Unruh said.

"It's what's called a pretensioned spring," Kolkowitz added. "If you just leave it sitting on a desk on its side it'll actually be fully compressed."

Held from midair, the Slinky stretches out, quickly reaching a condition known as "equilibrium." in which the downward force of gravity is balanced by the upward tension of the coils above it. When the top is released, the bottom stays suspended. The top of the Slinky collapses, so that the coils slam into each other. That collapse travels down as a wave through the Slinky. The bottom coils remain at rest until the top crashes into them.

And that's the key to understanding how the bottom of the Slinky remains suspended in midair for a short while.

"The bottom part of the Slinky hasn't deformed in any way," Kolkowitz explained. "Until that compression reaches the very bottom it won't move."

This levitation time -- approximately 0.3 seconds for Kolkowitz's own Slinky -- would be the same on any planet or moon. Gravity and tension of the spring effectively cancel each other out.

Kolkowitz said that one way of understanding this is that on the moon, the weaker gravitational field wouldn't stretch the Slinky as much, so the spring would compress more gently towards the bottom when dropped, taking the same 0.3 seconds to travel there. On Jupiter, the stronger gravitational field would stretch the suspended Slinky to a greater degree, so that the spring would have a larger distance to compress. But the more stretched-out top would snap back faster toward the bottom, resulting in the same levitation time.

As Kolkowitz pointed out, however, the Slinky's center of mass -- which shifts, but is always located somewhere in between the top and bottom of the toy -- still accelerates according to gravity all the way down to the ground from the moment it's released. So there's no violation of any of Newton's laws or Galileo's observations about falling objects.

The levitation time would only increase with a heavier Slinky and decrease if the coils were stiffer. The spring's mass and stiffness, Kolkowitz said, are the only two factors that affect the duration of levitation.

Kolkowitz pointed out this levitation effect would occur when any other spring or other elastic, nonrigid object is dropped -- and no object is completely rigid. "It's just that the Slinky is an especially easy system" in which to observe the effect, he said.

Another way to think about the levitation problem is that "the wave velocity in that Slinky is all that matters," Kolkowitz said. The wave velocity dictates "the length of time it takes information to reach the bottom of the Slinky," he said. Once that wave slams into the bottom, the bottom no longer levitates.

In his analysis, Unruh observed that the collision of the upper part of the Slinky with the motionless lower coils is an example of a shock wave, analogous to a sonic boom that occurs in aircraft traveling faster than the speed of sound. Moreover, the wave that moves through the toy travels parallel to the compression of the Slinky, making it a "longitudinal" wave, the same type of wave as a sound wave. The normal speed of this wave in a Slinky is best measured by how many loops per second the wave passes through, about 50-100 loops per second for a typical Slinky, depending on such things as the thickness of the coils.

But in a falling Slinky, the coils crash into each other, creating a shock wave.

According to Unruh, the velocity of the shock wave, when it reaches the bottom, is notably higher than the normal velocity of the Slinky wave, breaking a sort of "sound barrier" in the Slinky.

"This behavior of shock waves is typical," he wrote in an email to Inside Science. "The blast wave of a bomb gets to you faster than the sound of a bomb would if it were very small."

A shock wave is simply a statement that something in a physical system changes abruptly, in this case, the velocity of the lower coils in the Slinky.

"There is a lot of interesting physics in a very, very simple system," said Unruh.

Kolkowitz said that this is an easy experiment for anyone to duplicate: use a stopwatch to time the fall when a friend drops a Slinky. This technique depends on the reflexes of the person running the stopwatch and therefore could introduce some error.

Filming the falling Slinky with a video camera that captures a known number of frames per second and then counting the number of frames in which the bottom of the Slinky stays still would allow experimenters to more accurately calculate how long the Slinky's bottom stays suspended.

"It's just such an easy experiment to do and it's kind of fun," Kolkowitz said.

Though Kolkowitz doesn't use Slinky experiments in his quantum physics work, he said the surprising insights on the levitating Slinky shows how studying and measuring even everyday objects can provide results that are "counterintuitive and not what you expect."

Study from Cornell University

PhysOrg

Source: Inside Science News Service - via ZeitNews.org

 

Commonly in some of the world's poorest regions, kerosene lanterns are the standard form of night time lighting, which leads to the possibility of fires, explosions, asphyxiation and toxic fumes. Cheap, accessible solar lighting presents an obvious solution to this problem and the latest tilt at making this a reality is WakaWaka - a solar LED lamp concept that can fit snuggly onto a soda bottle.

Similar to Solar Pebble, LuminAID and Sollight, the WakaWaka lamp is a solar charged, portable LED lamp that hopes to hit the market with a low US$10 price tag, which is the equivalent of 2-3 months worth of toxic kerosene fuel. Unlike its competitors, the WakaWaka promises to provide 16 hours of light from one day of solar charge. Solar Pebble comes close with 12 hours of light but the others fall behind with only 4-6 hours of usage time.

Outside of poor rural environments the WakaWaka makes for a convenient camping torch, outdoor accessory, bedside reading light or mobile phone charger (compatible with 80% of commonly used cell phone battery brands excluding iPhone). The light-weight lamp is equipped with a replaceable battery which is said to last several years when used on a daily basis. Should it run on empty when not used for a couple of months, the user can simply charge it in the sun for a couple of hours and it's good to go.

As part of a Kickstarter initiative, the WakaWaka creators will donate three solar lamps to the students and teachers at the Mwamtsefu school in Kenya for every US$125 pledge or more. Given that the team have already raised over US$34,000 we hope that means that a lot of lamps are heading to Kenya!

WakaWaka is headed by Camille van Gestel, a founder of Off-Grid Solutions, a company that creates feasible and affordable solutions for families who do not have access to electricity. If you want to support this project, WakaWaka Kickstarter pledges start from US$1 and the campaign finishes on January 7.

Source: GizMag - via ZeitNews.org

 

Professor Karl Leo, Dr. Jan Blochwitz-Nimoth and Dr. Martin Pfeiffer were honored for their pioneering achievements in the field of organic electronics.

When the concept was first proposed, it was dismissed as being unrealizable: "It'll never work," commented one expert assessor of an application for research funding. Today, 15 years later, the physicist Professor Karl Leo and two of his colleagues have been presented with the "Deutscher Zukunftspreis", one of Germany's most prestigious research awards, for what was once a highly controversial idea. Leo, director of the Fraunhofer Institute for Photonic Microsystems IPMS in Dresden, has devoted most of his career to organic electronics. Until now, most electronic components have been made of inorganic silicon. The brittle material is a good semiconductor, but its manufacture requires a highly sophisticated process. It involves growing large crystals at high temperatures and then cutting them into thin slices known as wafers.

The more elegant solution is to use an organic material, a type of dye commonly used in the production of road signs. Such materials have the advantage that they can be applied as a coating on flexible films and other substrates. This gives rise to endless new possibilities, such as displays that can be rolled up and carried in a vest pocket or switchable window panes that light up at night to illuminate rooms while hardly consuming any electricity. On the other hand, organic dyes are poor electrical conductors. But this is where the once-mocked ingenious idea comes into play: their less-than-satisfactory conductivity can be increased by doping, i.e. adding a small amount of another chemical substance. After years of experiments, the researchers have succeeded in creating materials with an electrical conductivity a million and more times greater than the original dyes, with a doping ratio of no more than one percent.

The "Deutscher Zukunftspreis 2011", endowed with 250,000 euros, has been awarded by the President of the Federal Republic of Germany every year since 1997. It honors outstanding innovations that have made the transition from the research laboratory to industrial practice, thus helping to create jobs. Fraunhofer is a frequent winner of this prize, no doubt because it operates precisely at this interface between the world of research and the commercial market. This time, the jury chose to honor organic electronics, which Leo describes as a technology "that will revolutionize our lives".


From left: Karl Leo, Jan Blochwitz-Nimoth and Martin Pfeiffer.

The ultrathin semiconductor coatings have already made their way into mass production. They are equally versatile as the silicon chips that preceded them, for instance converting electrical energy into light just as easily as they convert sunlight into electricity. Novaled AG has adopted the first approach, using the technology to produce materials for displays and lamps, while Heliatek GmbH has chosen to focus on photovoltaics. Both of these companies are spinoffs created by former members of Professor Leo's research team. By now they employ a total of nearly 200 people, and work closely together with other Dresden-based companies in a technology network. This year's Zukunftspreis is shared by the founders of these two spinoffs, Jan Blochwitz-Nimoth (Novaled) and Martin Pfeiffer (Heliatek), and their mentor Professor Leo. Novaled AG is slightly further ahead in terms of marketing: the company is already mass-producing materials for cellphone displays. In two or three years' time, it intends to start supplying materials for ultraflat TV screens that display true-to-life colors and consume a minimum of energy. "OLED displays combine the best qualities of LED and plasma screens, the two technologies currently available," says Blochwitz-Nimroth. They are more energy-efficient than plasma TVs and deliver sharper images than LED technology, because they don't need backlighting.

Solar cells made of organic materials have not yet reached the mass market. Heliatek GmbH expects to start production sometime next year. The company's latest prototypes have an efficiency of ten percent, which is not yet high enough to compete with conventional silicon cells. "But in the longer term we will reach efficiencies approaching 20 percent", Professor Leo states. Moreover, organic cells have other advantages compared with silicon technology, foremost among them a simpler – and therefore cheaper – manufacturing process.

The method employed by Karl Leo and his prize-winning former colleagues involves depositing microscopically thin layers of the organic material on a substrate. These coatings have a thickness of no more than one fifth of a micrometer – one thousand times thinner than in conventional solar cells. Only about a gram of semiconductor material is needed to coat a surface area of one square meter – in a process that takes place at room temperature, not at the 1,000 or so degrees Celsius required to produce inorganic cells.

This not only saves energy but also allows PET films to be used as the substrate, instead of the heat-resistant glass that was previously the only option. PET is the same plastic used to make bottles for soft drinks. It is cheap, light and flexible. The prize-winners have developed a continuous process based on roll-to-roll technology that enables the solar cells to be manufactured cheaply in large numbers. The resulting lightweight modules can be installed on roofs too weak to support the weight of standard photovoltaic panels.

Before making its final choice, the jury had shortlisted three projects as potential winners of the "Deutscher Zukunftspreis". A second project rooted in Fraunhofer research was among this year's finalists, competing alongside the organic electronics team. These researchers have developed an advanced photovoltaic technology, known as "concentrated photovoltaics (CPV)", which consists of very-high-efficiency solar cells and sun-tracking concentrator modules. The nominated team comprised Andreas W. Bett, deputy director of the Fraunhofer Institute for Solar Energy Systems ISE, Hansjörg Lerchenmüller from Soitec Solar and Klaus-Dieter Rasch from AZUR SPACE Solar Power.

It was thus against such strong competitors that the organic electronics team led by Professor Leo won the "Deutscher Zukunftspreis 2011". German President Christian Wulff presented the award to Professor Karl Leo, Dr. Jan Blochwitz-Nimoth and Dr. Martin Pfeiffer in mid-December.

Source: Fraunhofer Society - via ZeitNews.org

 
By Admin (from 10/05/2012 @ 08:04:28, in en - Video Alert, read 1941 times)

We've heard of experimental contact lenses that can non-invasively monitor the blood sugar levels of diabetes sufferers before, but where prior research relied on chemical reactions inducing color-change in the lens, new joint research by the University of Washington and Microsoft Research aims to incorporate electronics into such lenses to report blood sugar levels wirelessly. Gizmag spoke to Desney Tan, Senior Researcher at Microsoft Research Connections, to find out what sets this work apart.

In a promotional video from Microsoft Research, Professor Babak Parviz of the University of Washington summarizes the research. "We've been able to put a glucose sensor on a contact lens and show that it can detect glucose at levels that are found in the tear film," he explains. "Our broader group has actually designed and built small radios that can interface with this glucose sensor and send out information wirelessly."

Sufferers of Type 1 diabetes have to monitor their blood sugar levels several times a day. It's a painful procedure requiring the piercing of the skin with a spring-loaded needle. With what Microsoft cites as an example of a Natural User Interface (NUI), it hopes its "Functional Contact Lens" may one day remove the need for this invasive means of monitoring.

Though the Functional Contact Lens aspires to a more advanced means of reporting than mere common change, the means of detection also differs from previous research. "There are now various groups working on non-invasive measurement of tear glucose," Desney Tan told Gizmag. "Professor Zhang's lab has been largely using nanostructured optical probes embedded in hydrophilic hydrogen lenses, and they've had some successes recently."Instead, Tan explained, this research uses an enzyme-based electrochemical process sensitive to glucose. "As the enzyme interacts with the tear fluid, specific measurements are made by observing the change in current measured by bio-compatible electrodes on the contact lens."

Microsoft hopes to get this technology to market "as soon as everything is ready", and, if successful, it's likely that the first models will report information wirelessly to a local device, which "could be an augmented smart phone," Tan suggests.

This will be achieved with tiny, flexible electronics embedded into the lens itself incorporating control circuits, communication circuits, the glucose sensors themselves, and the antenna. "This required a whole new engineering process, since traditional integrated circuit processes would not work," Tan explained.

It's hoped that subsequent models will enhance the NUI-ness of the user experience by removing the need for a secondary device, and instead displaying information directly in the contact lens. Tan told us that current challenges to overcome involve the efficiency of the wireless communications, "bio-compatibility", the practicality of the design with respect to potential mass production, as well as issues with the glucose sensor itself.

Bio-compatibility is clearly an issue when a (admittedly low-powered) electronic device comes into direct contact with the human eye - both in terms of safety and comfort. As such, the Functional Contact Lens is not yet read for what Tan calls "in-situation trials". Tan is a passionate evangelist for the potential of NUI and augmented reality. The team at Microsoft Research and the University of Washington "has only begun to scratch the surface of the opportunities that exist with this type of platform," he enthuses. "The most important challenge is really in the deep exploration of all the things not yet imagined with this platform, and new platforms enabled by this new-found capability to create other technology of this form."

Source: GIZMAG - via ZeitNews.org

 

Cannabis cured my skin cancer. This is my story. It has been proven that concentrated cannabis oil cures cancer.

 

Duration: 9 minutes and 15 seconds
Country: United States
Language: English
License: CC - Attribution Non-commercial No Derivatives
Genre: Documentary
Producer: D. Triplett
Director: D. Triplett
Views: 1.087.202 (1.012.502 embedded)
Posted by: fabulousbb on 30.04.2011

Source: dotsub.com


THREE and a half years ago, on my 62nd birthday, doctors discovered a mass on my pancreas. It turned out to be Stage 3 pancreatic cancer. I was told I would be dead in four to six months. Today I am in that rare coterie of people who have survived this long with the disease. But I did not foresee that after having dedicated myself for 40 years to a life of the law, including more than two decades as a New York State judge, my quest for ameliorative and palliative care would lead me to marijuana.

My survival has demanded an enormous price, including months of chemotherapy, radiation hell and brutal surgery. For about a year, my cancer disappeared, only to return. About a month ago, I started a new and even more debilitating course of treatment. Every other week, after receiving an IV booster of chemotherapy drugs that takes three hours, I wear a pump that slowly injects more of the drugs over the next 48 hours.

Nausea and pain are constant companions. One struggles to eat enough to stave off the dramatic weight loss that is part of this disease. Eating, one of the great pleasures of life, has now become a daily battle, with each forkful a small victory. Every drug prescribed to treat one problem leads to one or two more drugs to offset its side effects. Pain medication leads to loss of appetite and constipation. Anti-nausea medication raises glucose levels, a serious problem for me with my pancreas so compromised. Sleep, which might bring respite from the miseries of the day, becomes increasingly elusive.

Inhaled marijuana is the only medicine that gives me some relief from nausea, stimulates my appetite, and makes it easier to fall asleep. The oral synthetic substitute, Marinol, prescribed by my doctors, was useless. Rather than watch the agony of my suffering, friends have chosen, at some personal risk, to provide the substance. I find a few puffs of marijuana before dinner gives me ammunition in the battle to eat. A few more puffs at bedtime permits desperately needed sleep.

This is not a law-and-order issue; it is a medical and a human rights issue. Being treated at Memorial Sloan Kettering Cancer Center, I am receiving the absolute gold standard of medical care. But doctors cannot be expected to do what the law prohibits, even when they know it is in the best interests of their patients. When palliative care is understood as a fundamental human and medical right, marijuana for medical use should be beyond controversy.

Sixteen states already permit the legitimate clinical use of marijuana, including our neighbor New Jersey, and Connecticut is on the cusp of becoming No. 17. The New York State Legislature is now debating a bill to recognize marijuana as an effective and legitimate medicinal substance and establish a lawful framework for its use. The Assembly has passed such bills before, but they went nowhere in the State Senate. This year I hope that the outcome will be different. Cancer is a nonpartisan disease, so ubiquitous that it’s impossible to imagine that there are legislators whose families have not also been touched by this scourge. It is to help all who have been affected by cancer, and those who will come after, that I now speak.

Given my position as a sitting judge still hearing cases, well-meaning friends question the wisdom of my coming out on this issue. But I recognize that fellow cancer sufferers may be unable, for a host of reasons, to give voice to our plight. It is another heartbreaking aporia in the world of cancer that the one drug that gives relief without deleterious side effects remains classified as a narcotic with no medicinal value.

Because criminalizing an effective medical technique affects the fair administration of justice, I feel obliged to speak out as both a judge and a cancer patient suffering with a fatal disease. I implore the governor and the Legislature of New York, always considered a leader among states, to join the forward and humane thinking of 16 other states and pass the medical marijuana bill this year. Medical science has not yet found a cure, but it is barbaric to deny us access to one substance that has proved to ameliorate our suffering.

Gustin L. Reichbach is a justice of the State Supreme Court in Brooklyn.

A version of this op-ed appeared in print on May 17, 2012, on page A27 of the New York edition with the headline: A Judge’s Plea for Pot.

Source: NYtimes.com

 

The study published Jan. 9 online in the journal Circulation found the risk of heart attack remained eight times above normal during the first week after the death of a loved one, slowly declining, but remaining elevated for at least a month.

Researchers interviewed approximately 2,000 patients who suffered myocardial infarctions, or heart attacks, over a five-year period. Patients were asked a series of questions about potentially triggering events, including losing someone close to them in the past year.

While there is widespread anecdotal evidence that the death of a loved one can lead to declining health in survivors, few studies have looked at the acute effect of bereavement and grief on myocardial infarction.

"Bereavement and grief are associated with increased feelings of depression, anxiety and anger, and those have been shown to be associated with increases in heart rate and blood pressure, and changes in the blood that make it more likely to clot, all of which can lead to a heart attack," says lead author Elizabeth Mostofsky, MPH, ScD, a post-doctoral fellow in the cardiovascular epidemiological unit at BIDMC.

"Some people would say a 'broken heart' related to the grief response is what leads to these physiologic changes," says senior author Murray Mittleman, MD, DrPH, a physician in the Cardiovascular Institute at Beth Israel Deaconess Medical Center, an Associate Professor of Medicine at Harvard Medical School and director of BIDMC's cardiovascular epidemiological research program. "So that emotional sense of the broken heart may actually lead to damage leading to a heart attack and a physical broken heart of a sort."

Mostofsky and Mittleman think that being aware of the heightened risk can go a long way toward "breaking the link between the loss of someone close and the heart attack."

"Physicians, patients and families should to be aware of this risk and make sure that someone experiencing grief is getting their physical and medical needs met," says Mittleman. "And if an individual develops symptoms that we're concerned might reflect the beginnings of heart attack, we really need to take it very seriously and make sure that that patient gets appropriate evaluation and care."

Providing appropriate psychological interventions for someone who is grieving is also important. Mostofsky says, "We do think it's plausible that social support during that increased time of vulnerability would help mitigate the risk of heart attack."

Source: Beth Israel Deaconess Medical Center - via zeitnews.org

 

Ever wonder what trees, water skimmers and laundry detergent have in common? It turns out that the physical concept of surface tension is essential to their function.

The idea behind surface tension is that in a mixture of two molecular components -- let’s call them component "A" and component "B" -- the "A"s would really like to stick with their fellow "A"s and don’t want to be next to any "B"s, similar to boys and girls at a sixth-grade dance.

If you pour oil on a cup of water, the oil will quickly separate out to the top of the mixture to minimize the contact area between the two components. The higher the magnitude of the surface tension, the more the "A"s cannot stand the "B"s. Surface tension is important in many natural processes, including allowing trees to carry nutrients from the roots out to the branches and water skimmers to walk on the surface of water.

Conflict between different surface tensions

The interface between hydrophobic (oily) and hydrophilic (watery) components has very high interfacial tension, or surface tension. The magnitude of surface tension can be adjusted by adding amphiphilic molecules, ones that contain both hydrophilic and hydrophobic components, like soaps. These amphiphilic molecules prefer to be at the interface between the two components, and effectively lower the interfacial tension, allowing the components to mix more easily. At sufficiently low interfacial tension, small droplets of oil begin to dissolve in capsules called “micelles” composed of the amphiphilic molecules. This is how detergent causes oily stains to dissolve in water.

In a recently published article in Nature, an interdisciplinary team of researchers at Brandeis headed by Zvonimir Dogic, and consisting of experimental, theoretical and computational physicists as well as biologists, has demonstrated a new way of controlling interfacial tension using a molecular property called “chirality,” or lack of mirror symmetry. Examples of chiral structures include human hands and a DNA double helix.

The study was performed on a model system of two-dimensional colloidal membranes, a flexible sheet composed of micrometer-sized rod-like particles. Because the rods are chiral, they tend to twist in a small angle with respect to neighboring rods. However, the geometry of the membrane prevents twisting in the structure’s interior; only along the perimeter can the rods twist. Increasing the strength of chirality, or twistiness of the rods, lowers the energy of the rods along the membrane’s edge, also lowering the interfacial tension.

By manipulating the microscopic shape, the team of researchers was able to create reversible transitions of a flat two-dimensional membrane to a one-dimensional twisted ribbon. Engineering this system that creates reversible transitions is part of an overall research mission to manipulate microscale structures of materials.

In the first movie, the twisted ribbons have much more interfacial area than the membranes, but are much “twistier” structures, and are therefore favored when the strength of chirality is relatively high.

Additionally, in the movie below, researchers illustrate how they can drive the same membrane-to-ribbon transition using optical tweezers, an instrument that uses laser light to grab objects and move them around.

This work presents a powerful new method to control the assembly of materials, the researchers found.

Source: Brandeis University - via ZeitNews.org

 
By Admin (from 01/06/2012 @ 11:07:44, in en - Video Alert, read 2160 times)

For a little over 50 years, an elite organization has met all around the world in total secrecy with nearly zero press coverage. On Thursday, the annual Bilderberg Conference will take place in Chantilly, Virginia where the world's leaders are believed to make decisions that could possibly have an effect on the world. Abby Martin looks closer at Bilderberg's global policies for a new world order as RT readies to cover this year's event later this week.

Sources:

http://twitter.com/RT_America
http://www.facebook.com/RTAmerica

Brief history

Bilderberg takes its name from the hotel in Holland, where the first meeting took place in May 1954. That pioneering meeting grew out of the concern expressed by leading citizens on both sides of the Atlantic that Western Europe and North America were not working together as closely as they should on common problems of critical importance. It was felt that regular, off-the-record discussions would help create a better understanding of the complex forces and major trends affecting Western nations in the difficult post-war period.
The Cold War has now ended. But in practically all respects there are more, not fewer, common problems - from trade to jobs, from monetary policy to investment, from ecological challenges to the task of promoting international security. It is hard to think of any major issue in either Europe or North America whose unilateral solution would not have repercussions for the other.
Thus the concept of a European-American forum has not been overtaken by time. The dialogue between these two regions is still - even increasingly - critical.

Character of meetings

What is unique about Bilderberg as a forum is

 

  • the broad cross-section of leading citizens that are assembled for nearly three days of informal and off-the-record discussion about topics of current concern especially in the fields of foreign affairs and the international economy;
  •  
  • the strong feeling among participants that in view of the differing attitudes and experiences of the Western nations, there remains a clear need to further develop an understanding in which these concerns can be accommodated;
  •  
  • the privacy of the meetings, which has no purpose other than to allow participants to speak their minds openly and freely.

 

In short, Bilderberg is a small, flexible, informal and off-the-record international forum in which different viewpoints can be expressed and mutual understanding enhanced. Bilderberg's only activity is its annual Conference. At the meetings, no resolutions are proposed, no votes taken, and no policy statements issued. Since 1954, fifty-nine conferences have been held. For each meeting, the names of the participants as well as the agenda are made Public and available to the press.

Participants

Invitations to Bilderberg conferences are extended by the Chairman following consultation with the Steering Committee members. Participants are chosen for their experience, their knowledge, their standing and their contribution to the selected agenda.
There usually are about 120 participants of whom about two-thirds come from Europe and the balance from North America. About one-third is from government and politics, and two-thirds from finance, industry, labour, education and communications. Participants attend Bilderberg in a private and not an official capacity.

Governance and Funding

Bilderberg is governed by a Steering Committee which designates a Chairman; members are elected for a term of four years and can be re-elected. There are no other members of the Bilderberg conference. The Chair's main responsibilities are to chair the Steering Committee and to prepare with the Steering Committee the conference program, the selection of participants. He also makes suggestions to the Steering Committee regarding its composition. The Executive Secretary reports to the Chairman.

The expenses of maintaining the small Secretariat of the Bilderberg meetings are covered wholly by private subscription. The hospitality costs of the annual meeting are the responsibility of the Steering Committee member(s) of the host country.

Source: bilderbergmeetings.org

 

A team of researchers from the University of Illinois at Urbana-Champaign (UIUC) and the U.S. Department of Energy's (DOE) Argonne National Laboratory are exploring ways to design batteries that heal themselves when damaged.

"This would help electronics survive daily use—both the long-term damage caused by charging over and over again, and also the inevitable physical damage of everyday life," said Jeff Moore, a UIUC scientist on the team.

Scientists think that loss of electrical conductivity is what causes a battery to fade and die. Theories abound on the specific molecular failures; perhaps chemicals build up on electrodes, or the electrodes themselves pull away. Perhaps it's simply the inevitable stress fractures in materials forced to expand and contract repeatedly as the battery is charged and used.

In any case, the battery's storage capacity drops due to loss of electrical conductivity. This is what the team wants to address.

The idea is to station a team of "emergency repairmen" already contained in the battery. These are tiny microspheres, each smaller than a single red blood cell, and containing liquid metal inside. Added along with the battery components, they lie dormant for most of the battery's lifetime.

But if the battery is damaged, the capsules burst open and release their liquid metal into the battery. The metal fills in the gaps in the electrical circuit, connecting the broken lines, and power is restored.

Capsules could be designed to be triggered by different events—some that respond to physical damage and others that respond to overheating, for example. This would allow scientists to tailor the contents of the different capsules to repair specific situations.

Microcapsules have been manufactured in large scale since the 1950s. When you press your pencil down on carbonless copy paper, microcapsules full of ink burst open to leave an imprint on the paper layers beneath. Microcapsules full of perfume burst when you rub a scratch-and-stiff sticker.

"We hope that using microcapsules, which are a well-known technology, could make this technology easy to scale up for commercial use," Moore said.

The team's first step was to test the system in a simple system, connecting an electrode with a wire to see if the capsules could "heal" the circuit if cut. (Watch a demonstration of this in the video above).

"Our new self-healing materials can completely repair the circuit in less than a millisecond," Moore said.

The next step, which the researchers are beginning, is to test the capsules in a prototype battery. Argonne materials scientist and battery expert Khalil Amine is helping the team adapt the capsules for lithium-ion batteries. Other collaborators are UIUC scientists Nancy Sottos and Scott White.

The work is funded through the Center for Electrical Energy Storage (CEES), one of three Argonne-led Energy Frontier Research Centers (EFRCs). Established in 2009 by a special block grant from DOE, the EFRCs are five-year interdisciplinary programs focused around specific scientific challenges that are believed to be key to breakthroughs in energy technology.

The CEES is addressing the problems that limit electrochemical energy storage technologies—such as batteries and supercapacitors—for transportation, residential and commercial use.

The results have been published in a paper, "Autonomic Restoration of Electrical Conductivity", in the journal Advanced Materials. Moore's co-authors on the paper are Benjamin Blaiszik, Sharlotte Kramer, Martha Grady, David McIlroy, Nancy Sottos and Scott White.

Source: Argonne National Laboratory - via ZeitNews.org

 
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