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3D-printing a new lifelike liver tissue for drug screening

3D-printing a new lifelike liver tissue for drug screening | Amazing Science | Scoop.it

University of California, San Diego researchers have 3D-printed a tissue that closely mimics the human liver’s sophisticated structure and function. The new model could be used for patient-specific drug screening and disease modeling and could help pharmaceutical companies save time and money when developing new drugs, according to the researchers.


The liver plays a critical role in how the body metabolizes drugs and produces key proteins, so liver models are increasingly being developed in the lab as platforms for drug screening. However, so far, the models lack both the complex micro-architecture and diverse cell makeup of a real liver. For example, the liver receives a dual blood supply with different pressures and chemical constituents.


So the team employed a novel bioprinting technology that can rapidly produce complex 3D microstructures that mimic the sophisticated features found in biological tissues.


  • The team printed a honeycomb pattern of 900-micrometer-sized hexagons, each containing liver cells derived fromhuman induced pluripotent stem cells. An advantage of human induced pluripotent stem cells is that they are patient-specific, which makes them ideal materials for building patient-specific drug screening platforms. And since these cells are derived from a patient’s own skin cells, researchers don’t need to extract any cells from the liver to build liver tissue.
  • Then, endothelial and mesenchymal supporting cells were printed in the spaces between the stem-cell-containing hexagons.


The entire structure — a 3 × 3 millimeter square, 200 micrometers thick — takes just seconds to print. The researchers say this is a vast improvement over other methods to print liver models, which typically take hours. Their printed model was able to maintain essential functions over a longer time period than other liver models. It also expressed a relatively higher level of a key enzyme that’s considered to be involved in metabolizing many of the drugs administered to patients.

“It typically takes about 12 years and $1.8 billion to produce one FDA-approved drug,” said Shaochen Chen, NanoEngineering professor at the UC San Diego Jacobs School of Engineering. “That’s because over 90 percent of drugs don’t pass animal tests or human clinical trials. We’ve made a tool that pharmaceutical companies could use to do pilot studies on their new drugs, and they won’t have to wait until animal or human trials to test a drug’s safety and efficacy on patients. This would let them focus on the most promising drug candidates earlier on in the process.”
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New method enables discovery of 3D structures for molecules important to medicine

New method enables discovery of 3D structures for molecules important to medicine | Amazing Science | Scoop.it

Researchers have overcome a long-standing technical barrier to imaging 3D structures of thousands of molecules important to medicine and biology. The 3D structures of many protein molecules have been discovered using a technique called X-ray crystallography, but the method relies on scientists being able to produce highly ordered crystals containing the protein molecules in a regular arrangement. When X-rays are shone on highly ordered crystals, the X-rays scatter and produce regular patterns of spots called Bragg peaks (see figure above, left). High-quality Bragg peaks contain the information to produce high-resolution 3D structures of proteins.


Unfortunately, many important and complex biomolecules do not form highly ordered crystals; instead, the protein arrangements are slightly disordered. When X-rays are shone on these more disordered crystals, a smaller number of Bragg peaks are produced, along with a vague pattern of light and shadow known as a continuous diffraction pattern (right).


In the past, scientists discarded these less-than-perfect crystals. Unfortunately, many of the molecules forming disordered crystals are important molecular complexes such as those that span cell membranes.


So a team led by Professor Henry Chapman from the Center for Free-Electron Laser Science at DESY in Hamberg, Germany turned to the world’s most powerful X-ray laser: the SLAC LCLS at Stanford University. Kartik Ayyer, PhD., lead author of the article in Nature, explains that the method uses an approach similar to that used to image a single molecule.


“If you would shoot X-rays on a single molecule, it would produce a continuous diffraction pattern free of any Bragg spots,” he says. “The pattern would be extremely weak, however, and very difficult to measure. But the ‘background’ in our crystal analysis is like accumulating many shots from individually aligned single molecules. We essentially just use the crystal as a way to get a lot of single molecules, aligned in common orientations, into the beam.”


As the model protein, the researchers crystallized photosystem II (PSII), a large membrane–protein complex of photosynthesis that plants use to produce oxygen for life on Earth. After exposing the crystal to X-rays, the researchers first analyzed the Bragg peaks of PSII to produce a low-resolution outline of the 3D structure. They then improved this data, using an algorithm, to analyze the continuous diffraction pattern and produced a higher-resolution 3D structure.


This novel method means that imperfect crystals containing a slightly disordered protein arrangement can now be used to “directly view large protein complexes in atomic detail,” says Chapman. “This kind of continuous diffraction has actually been seen for a long time from many different poorly diffracting crystals,” says Chapman. “It wasn’t understood that you can get structural information from it and so analysis techniques suppressed it.

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‘Eternal' 5D data storage could reliably record the history of humankind for billions of years

‘Eternal' 5D data storage could reliably record the history of humankind for billions of years | Amazing Science | Scoop.it

Digital documents stored in nano-structured dots in glass for billions of years could survive the end of the human race.


Scientists at the University of Southampton Optoelectronics Research Centre (ORC) have developed the first digital data storage system capable of creating archives that can survive for billions of years. Using nanostructured glass, the system has 360 TB per disc capacity, thermal stability up to 1,000°C, and virtually unlimited lifetime at room temperature (or 13.8 billion years at 190°C ).


As a “highly stable and safe form of portable memory,” the technology opens up a new era of “eternal” data archiving that could be essential to cope with the accelerating amount of information currently being created and stored, the scientists says.* The system could be especially useful for organizations with big archives, such as national archives, museums, and libraries, according to the scientists.


The recording system uses an ultrafast laser to produce extremely short (femtosecond) and intense pulses of light. The file is written in three layers of nanostructured dots separated by five micrometers (one millionth of a meter) in fuzed quartz (coined as a “Superman memory crystal” (as in “memory crystals” used in the Superman films).”


The self-assembled nanostructures change the way light travels through glass, modifying the polarization of light, which can then be read by a combination optical microscope and polarizer, similar to that found in Polaroid sunglasses. The recording method is described as “5D” because the information encoding is in five dimensions — three-dimensional position plus size and orientation.


So far, the researchers have saved major documents from human history, such as the Universal Declaration of Human Rights (UDHR), Newton’s OpticksMagna Carta, and Kings James Bible as digital copies. A copy of the UDHR encoded to 5D data storage was recently presented to UNESCO by the ORC at the International Year of Light (IYL) closing ceremony in Mexico.


The team is now looking for industry partners to further develop and commercialize this technology. The researchers will present their research at the photonics industry’s SPIE (the International Society for Optical Engineering Conference) in San Francisco on Wednesday Feb. 17.


* In 2008, the International Data Corporation [found] that total capacity of data stored is increasing by around 60% each year. As a result, more than 39,000 exabytes of data will be generated by 2020. This amount of data will cause a series of problems and one of the main will be power consumption. 1.5% of the total U.S. electricity consumption in 2010 was given to the data centers in the U.S. According to a report by the Natural Resources Defence Council, the power consumption of all data centers in the U.S. will reach roughly 140 billion kilowatt-hours per each year by 2020. This amount of electricity is equivalent to that generated by roughly thirteen Heysham 2 nuclear power stations (one of the biggest stations in UK, net 1240 MWe).


Most of these data centers are built based on hard-disk drive (HDD), with only a few designed on optical discs. HDD is the most popular solution for digital data storage according to the International Data Corporation. However, HDD is not an energy-efficient option for data archiving; the loading energy consumption is around 0.04 W/GB. In addition, HDD is an unsatisfactory candidate for long-term storage due to the short lifetime of the hardware and requires transferring data every two years to avoid any loss.

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Visualizing Cross-Sectional Data in a Real-World Context

Visualizing Cross-Sectional Data in a Real-World Context | Amazing Science | Scoop.it
Combining the capabilities of an open-source drawing tool with Google Earth maps allows researchers to visualize real-world cross-sectional data in three dimensions.


If you could fly around your research results in three dimensions, wouldn’t you like to do it? Visualizing research results properly during scientific presentations already does half the job of informing the public on the geographic framework of your research. Many scientists use Google Earth™ mapping service (V7.1.2.2041) because it’s a great interactive mapping tool for assigning geographic coordinates to individual data points, localizing a research area, and draping maps of results over Earth’s surface for displaying the results in three dimensions. Yet scientists often do not fully explore the Google Earth™ platform.


Visualizations of research results in vertical cross sections through these maps are often not shown at the same time as the maps. However, a few tutorials to display cross-sectional data in Google Earth™ do exist, and the workflow is rather simple. By importing cross-sectional data into in the open software SketchUp Make [Trimble Navigation Limited, 2016], any spatial model displaying research results can be exported to a vertical figure in Google Earth™. A website now explains an easy workflow including tips, and discusses some of the endless applications of the method. This workflow will give researchers better spatial visibility of their results and will allow for more dynamic scientific presentations.


Via Dr. Catherine Russell
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Mining social media can help improve disaster response efforts

Mining social media can help improve disaster response efforts | Amazing Science | Scoop.it

Leveraging publicly available social media posts could help disaster response agencies quickly identify impacted areas in need of assistance, according to a Penn State-led team of researchers. By analyzing the September 2013 Colorado floods, researchers showed that a combination of remote sensing, Twitter and Flickr data could be used to identify flooded areas.


"FEMA (the Federal Emergency Management Agency), the Red Cross and other response agencies use social media now to disseminate relevant information to the general public," said said Guido Cervone, associate professor of geography and associate director of the Penn State's Institute for CyberScience. "We have seen here that there is potential to use social media data from community members to help identify hotspots in need of aid, especially when it is paired with remote sensing imagery of the area."


After a disaster, response teams typically prioritize rescue and aid efforts with help from imagery and other data that show what regions are affected the most. Responders commonly use satellite imagery, but this on its own has drawbacks.


"Publicly available satellite imagery for a location isn't always available in a timely manner -- sometimes it can take days before it becomes available," said Elena Sava, graduate student in geography, Penn State. "Our research focused on identifying data in non-traditional data streams that can prove mission critical for specific areas where there might be damage. We wanted to see if social media could help filling the gaps in the satellite data."


The 2013 Colorado flooding was an unprecedented event. In nine days in September, Boulder, Colo., received more than 43 centimeters, or 17 inches of rain -- nearly the amount of rainfall it normally receives in a year. Officials evacuated more than 10,000 people and had to rescue several thousand people and pets.


Because the flooding occurred in an urban setting, the researchers were able to access more than 150,000 tweets from people affected by the flooding. Using a tool called CarbonScanner, they identified clusters of posts suggesting possible locations of damage. Then, they analyzed more than 22,000 photos from the area obtained through satellites, Twitter, Flickr, the Civil Air Patrol, unmanned aerial vehicles and other sources.

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MIT wins design competition for Elon Musk's Hyperloop

MIT wins design competition for Elon Musk's Hyperloop | Amazing Science | Scoop.it
MIT student engineers won a competition to transform SpaceX and Tesla Motors co-founder Elon Musk's idea into a design for a Hyperloop to move pods of people at high speed.


An image released by Tesla Motors, is a sketch of the Hyperloop capsule with passengers onboard. . Billionaire entrepreneur Elon Musk on Monday, Aug. 12, 2013 unveiled a concept for a transport system he says would make the nearly 400-mile trip in half the time it takes an airplane. The "Hyperloop" system would use a large tube with capsules inside that would float on air, traveling at over 700 miles per hour.


The Massachusetts Institute of Technology, based in Cambridge, Massachusetts, was named the winner Saturday after a competition among more than 1,000 college students at Texas A&M University in College Station. The Hyperloop is a high-speed ground transport concept proposed by Musk to transport "pods" of 20 to 30 people through a 12-foot diameter tube at speeds of roughly 700 mph. More than 100 university teams presented design concepts to a panel of judges in an event that began Friday.


Delft University of Technology from The Netherlands finished second, the University of Wisconsin third, Virginia Tech fourth and the University of California, Irvine, fifth.


The top teams will build their pods and test them at the world's first Hyperloop Test Track, being built adjacent to SpaceX's Hawthorne, California, headquarters.


Inventor Musk to share plans for high-speed travel (Update)


More information: hyperloop.tamu.edu/ 

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Delivering the internet of the future - at the speed of light

Delivering the internet of the future - at the speed of light | Amazing Science | Scoop.it

The research by High Performance Networks (HPN) group in the University of Bristol’s Department of Electrical and Electronic Engineering has found, for the first time, a scientific solution that enables future internet infrastructure to become completely open and programmable while carrying internet traffic at the speed of light.


The current internet infrastructure is not able to support independent development and innovation at physical and network layer functionalities, protocols, and services, while at the same time supporting the increasing bandwidth demands of changing and diverse applications.


The research addresses this problem with a new high performance network infrastructure that is open and programmable and uses light to carry internet traffic.  It introduces new concepts of open source optical internet enabled by optical white box and software defined network technologies


Dr Reza Nejabati, Reader in Optical Networks in the HPN group, said: “Hardware and software technologies reported in this paper can potentially revolutionised optical network infrastructure the same way that Google Android and Apple iOS did for mobile phones. These technologies will hide complexity of optical networks and open them up for traditional programmers and application developers to create new type of internet applications taking advantages of speed of light.”


Dimitra Simeonidou, Professor of High Performance Networks and who leads the HPN group, added: “New internet technologies frequently emerge, but most of them rarely result in new and revolutionary internet applications. The technologies suggested could pave the way for the creation of new internet services and applications not previously possible or disruptive. The technologies could also potentially change the balance of power from vendors and operators that are monopolising the current internet infrastructure to wider users and service providers.”


Reference: Optical network democratization by Reza Nejabati, Shuping Peng and Dimitra Simeonidou is published in the Philosophical Transactions of the Royal Society A.


About the High Performance Networks (HPN) group
The High Performance Networks group (HPN) led by Professor Dimitra Simeonidou specialises in the application of advanced hardware and software technologies, targeting the future optical networks for Internet of Things (IoTs), data centres, grid/cloud-based applications and distributed technologies etc.  The group is equipped with world-class laboratories, including state-of-the-art optical transmission testbeds, and software-defined network experimental platform.

The group has been at the forefront of world research and development in the fields of:

  • Next generation optical transmission networks;
  • Optical packet and burst switching;
  • Optical data centre solutions and architecture;
  • Grid and cloud networking;
  • Software-defined networking (SDN) and optical network virtualization;
  • Hybrid-network domains orchestration and service management;
  • Smart City ICT Solutions.

The HPN laboratory has dedicated connectivity to both national and international research network infrastructures and forms part of the UK National Dark Fibre Infrastructure Service (NDFIS). This network infrastructure has enabled the development of close collaborations with leading research institutions and industry across the UK, Europe, USA, Brazil and Japan.


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Marc Kneepkens's curator insight, January 26, 2016 4:49 PM

Another giant step.

The Asymptotic Leap's curator insight, January 27, 2016 11:43 AM

The global brain...operating at the speed of light. 

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New handheld miniature microscope could ID cancer cells in doctor’s offices and operating rooms

New handheld miniature microscope could ID cancer cells in doctor’s offices and operating rooms | Amazing Science | Scoop.it

A miniature handheld microscope being developed by University of Washington mechanical engineers could allow neurosurgeons to differentiate cancerous from normal brain tissue at cellular level in real time in the operating room and determine where to stop cutting.


The new technology is intended to solve a critical problem in brain surgery: to definitively distinguish between cancerous and normal brain cells, during an operation, neurosurgeons would have stop the operation and send tissue samples to a pathology lab — where they are typically frozen, sliced, stained, mounted on slides and investigated under a bulky microscope.


Developed in collaboration with Memorial Sloan Kettering Cancer Center, Stanford University and the Barrow Neurological Institute, the new microscope is outlined in an open-access paper published in January in the journalBiomedical Optics Express.


“Surgeons don’t have a very good way of knowing when they’re done cutting out a tumor,” said senior author Jonathan Liu, UW assistant professor of mechanical engineering. “They’re using their sense of sight, their sense of touch, and pre-operative images of the brain — and oftentimes it’s pretty subjective. “Being able to zoom and see at the cellular level during the surgery would really help them to accurately differentiate between tumor and normal tissues and improve patient outcomes.”


The handheld microscope, roughly the size of a pen, combines technologies in a novel way to deliver high-quality images at faster speeds than existing devices. Researchers expect to begin testing it as a cancer-screening tool in clinical settings next year.

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How the GyroGlove Steadies Hands of Parkinson’s Patients

How the GyroGlove Steadies Hands of Parkinson’s Patients | Amazing Science | Scoop.it
A wearable device promises to help steady hand tremors by using an old technology—gyroscopes.


When he was a 24-year-old medical student living in London, Faii Ong was assigned to care for a 103-year-old patient who suffered from Parkinson’s, the progressive neurological condition that affects a person’s ease of movement. After watching her struggle to eat a bowl of soup, Ong asked another nurse what more could be done to help the woman. “There’s nothing,” he was grimly told.


Ong, now 26, didn’t accept the answer. He began to search for a solution that might offset the tremulous symptoms of Parkinson’s, a disease that affects one in 500 people, not through drugs but physics. After evaluating the use of elastic bands, weights, springs, hydraulics, and even soft robotics, Ong settled on a simpler solution, one that he recognized from childhood toys. “Mechanical gyroscopes are like spinning tops: they always try to stay upright by conserving angular momentum,” he explains. “My idea was to use gyroscopes to instantaneously and proportionally resist a person’s hand movement, thereby dampening any tremors in the wearer’s hand.”


Together with a number of other students from Imperial College London, Ong worked in the university’s prototyping laboratory to run numerous tests. An early prototype of a device, called GyroGlove, proved his instinct correct. Patients report that wearing the GyroGlove, which Ong believes to be the first wearable treatment solution for hand tremors, is like plunging your hand into thick syrup, where movement is free but simultaneously slowed. In benchtop tests, the team found the glove reduces tremors by up to 90 percent.


GyroGlove’s design is simple. It uses a miniature, dynamically adjustable gyroscope, which sits on the back of the hand, within a plastic casing attached to the glove’s material. When the device is switched on, the battery-powered gyroscope whirs to life. Its orientation is adjusted by a precession hinge and turntable, both controlled by a small circuit board, thereby pushing back against the wearer’s movements as the gyroscope tries to right itself.


While the initial prototypes of the device still require refinements to size and noise, Alison McGregor, professor of musculoskeletal biodynamics at Imperial College, who has been a mentor to the team, says the device “holds great promise and could have a significant impact on users’ quality of life.” Helen Matthews of the Cure Parkinson’s Trust agrees: “GyroGlove will make everyday tasks such as using a computer, writing, cooking, and driving possible for sufferers,” she says.

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Mike Oehme's curator insight, January 26, 2016 2:47 AM

Interesting idea, unfortunately I don't have a gyro trainer at home anymore

 

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NIST simulates fast, accurate DNA sequencing through graphene nanopore

NIST simulates fast, accurate DNA sequencing through graphene nanopore | Amazing Science | Scoop.it

Researchers at the National Institute of Standards and Technology (NIST) have simulated a new concept for rapid, accurate gene sequencing by pulling a DNA molecule through a tiny chemically activated hole in graphene—an ultrathin sheet of carbon atoms—and detecting changes in electrical current.


The NIST simulation study suggests the method could identify about 66 million bases per second with 90 percent accuracy and no false positives. If demonstrated experimentally, the NIST method might ultimately be faster and cheaper than conventional DNA sequencing, meeting a critical need for applications such as forensics.


Conventional sequencing, developed in the 1970s, involves separating, copying, labeling and reassembling pieces of DNA to read the genetic information. The new NIST proposal is a twist on the more recent “nanopore sequencing” idea of pulling DNA through a hole in specific materials, originally a protein (see “First full genome of a living organism sequenced and assembled using smartphone-size device“).


This concept—pioneered 20 years ago at NIST—is based on the passage of electrically charged particles (ions) through the pore. The idea remains popular but poses challenges such as unwanted electrical noise, or interference, and inadequate selectivity.

By contrast, NIST’s new proposal is to create temporary chemical bonds and rely on graphene’s capability to convert the mechanical strains (rather than charged particles) from breaking those bonds into measurable blips in electrical current.


“This is essentially a tiny strain sensor,” says NIST theorist Alex Smolyanitsky, who came up with the idea and led the project. “We did not invent a complete technology. We outlined a new physical principle that can potentially be far superior to anything else out there.”


Graphene is popular in nanopore-sequencing proposals due to its electrical properties and miniaturized thin-film structure. In the new NIST method, a graphene nanoribbon (4.5 by 15.5 nanometers) has several copies of a base attached to the nanopore (2.5 nm wide). DNA’s genetic code is built from four kinds of bases, which bond in pairs as cytosine–guanine and thymine–adenine.


In simulations of how the sensor would perform at room temperature in water, cytosine is attached to the nanopore to detect guanine. A single-strand (unzipped) DNA molecule is pulled through the pore. When guanine passes by, hydrogen bonds form with the cytosine. As the DNA continues moving, the graphene is yanked and then slips back into position as the bonds break.


The NIST study focused on how this strain affects graphene’s electronic properties and found that temporary changes in electrical current indeed indicate that a target base has just passed by. To detect all four bases, four graphene ribbons, each with a different base inserted in the pore, could be stacked vertically to create an integrated DNA sensor.


The researchers combined simulated data with theory to estimate levels of measurable signal variations. Signal strength was in the milliampere range, stronger than in the earlier ion-current nanopore methods.


Based on the performance of 90 percent accuracy without any false positives (i.e., errors were due to missed bases rather than wrong ones), the researchers suggest that four independent measurements of the same DNA strand would produce 99.99 percent accuracy, as required for sequencing the human genome.


The study authors concluded that the proposed method shows “significant promise for realistic DNA sensing devices” without the need for advanced data processing, microscopes, or highly restricted operating conditions. Other than attaching bases to the nanopore, all sensor components have been demonstrated experimentally by other research groups. Theoretical analysis suggests that basic electronic filtering methods could isolate the useful electrical signals. The proposed method could also be used with other strain-sensitive membranes, such as molybdenum disulfide.

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WUSTL Team develops wireless, dissolvable sensors to monitor brain

WUSTL Team develops wireless, dissolvable sensors to monitor brain | Amazing Science | Scoop.it

A team of neurosurgeons and engineers has developed wireless brain sensors that monitor intracranial pressure and temperature and then are absorbed by the body, negating the need for surgery to remove the devices. Such implants, developed by scientists at Washington University School of Medicine in St. Louis and engineers at the University of Illinois at Urbana-Champaign, potentially could be used to monitor patients with traumatic brain injuries, but the researchers believe they can build similar absorbable sensors to monitor activity in organ systems throughout the body. Their findings are published online Jan. 18, 2015 in the journal Nature.


"Electronic devices and their biomedical applications are advancing rapidly," said co-first author Rory K. J. Murphy, MD, a neurosurgery resident at Washington University School of Medicine and Barnes-Jewish Hospital in St. Louis. "But a major hurdle has been that implants placed in the body often trigger an immune response, which can be problematic for patients. The benefit of these new devices is that they dissolve over time, so you don't have something in the body for a long time period, increasing the risk of infection, chronic inflammation and even erosion through the skin or the organ in which it's placed. Plus, using resorbable devices negates the need for surgery to retrieve them, which further lessens the risk of infection and further complications." Murphy is most interested in monitoring pressure and temperature in the brains of patients with traumatic brain injury.


About 50,000 people die of such injuries annually in the United States. When patients with such injuries arrive in the hospital, doctors must be able to accurately measure intracranial pressure in the brain and inside the skull because an increase in pressure can lead to further brain injury, and there is no way to reliably estimate pressure levels from brain scans or clinical features in patients.


"However, the devices commonly used today are based on technology from the 1980s," Murphy explained. "They're large, they're unwieldy, and they have wires that connect to monitors in the intensive care unit. They give accurate readings, and they help, but there are ways to make them better."

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Bio-Powered Chips Might One Day Fit Inside Cells

Bio-Powered Chips Might One Day Fit Inside Cells | Amazing Science | Scoop.it

For the first time, researchers have developed a microchip that is powered by the same energy-rich molecules that fuel living cells, researchers say. Thisadvance could one day lead to devices that are implanted within cells and harvest biological energy to operate.


The molecule adenosine triphosphate (ATP) stores chemical energy and is used inside cells to ferry energy from where it is generated to where it is consumed. The new microchip relies on enzymes known as sodium-potassium ATPases. These molecules break down ATP to release energy the enzymes use to pump sodium and potassium ions across membranes, generating an electrical potential during the process.


“Ion pumps are electronics-like components in living systems,” says study senior author Ken Shepard, an electrical engineer at Columbia University in New York. Shepard and his colleagues detailed their findings in the 7 December edition of the journal Nature Communications.


The researchers embedded sodium-potassium ATPases taken from pig brains in artificial fatty membranes. There were more than 2 million of these molecules active per square millimeter of the membranes, about 5 percent of the density naturally occurring in mammalian nerve fibers.


In the presence of ATP, these ion pumps generated 78 millivolts. A “biocell” of two membranes provides enough of a voltage to operate a CMOS integrated circuit. The ion pumps have a chemical-to-electrical energy conversion efficiency of of 14.9 percent.


“These ion pumps generated an electrical field that we harnessed to power a solid-state system,” Shepard says.


Since ATP is only really found within cells and not in the bloodstream, Shepard cautions that this new system is not a way to power conventional implantable medical devices such as pacemakers.


“However, such a system might power an implant small enough to sit inside a cell,” Shepard says. “Solid-state materials are already used in nanoparticles for various therapeutic and imaging purposes in the body, but those are all just passive materials. Our idea is to make something that would have the ability to compute and act, to make decisions and then actuate in some way.”

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GM and Lyft Are Teaming Up to Build a Network of Self-Driving Cars

GM and Lyft Are Teaming Up to Build a Network of Self-Driving Cars | Amazing Science | Scoop.it

General Motors and Lyft are teaming up to create a national network of self-driving cars, the companies jointly announced this morning.

GM will invest $500 million in Lyft and take a seat on the ride-sharing startup’s board of directors. It will also become a preferred provider of cars for short-term use to Lyft drivers.


GM, America’s biggest automaker, has been working on autonomous technology since it first collaborated with Carnegie Mellon University in 2007, for an autonomous vehicle competition sponsored by DARPA. Next year, it plans to finally put a related product on the market: “Super Cruise,” a semi-autonomous feature that will let a car handle itself on the highway, will be available on the 2017 Cadillac CT6.


The partnership with Lyft, though, signifies ambitions far beyond Super Cruise. While we have no details on the proposed “network of on-demand autonomous vehicles”—such as how it will work or when it will arrive—we can assume it will require a far more advanced take on autonomous driving than Super Cruise will offer. Lyft, like other ride-sharing services, does the bulk of its work in cities, which are devilishly hard for robots to navigate. Urban areas are full of complicated intersections, pedestrians, cyclists, and other hard-to-predict variables.

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Cancer cell imaging in 3D

Cancer cell imaging in 3D | Amazing Science | Scoop.it

Cancer cells don’t live on glass slides. Yet the vast majority of images related to cancer biology come from the cells being photographed on flat, two-dimensional surfaces — images sometimes used to draw conclusions about the behavior of cells that normally reside in a more complex environment.


Now a new high-resolution microscope, presented (open access) February 22 in Developmental Cell, makes it possible to visualize cancer cells in 3D and record how they are signaling to other parts of their environment — revealing previously unappreciated biology of how cancer cells survive and disperse within living things. Based on ”microenvironmental selective plane illumination microscopy” (meSPIM),  the new microscope is designed to image cells in microenvironments free of hard surfaces near the sample.


“There is clear evidence that the environment strongly affects cellular behavior — thus, the value of cell culture experiments on glass must at least be questioned,” says senior author Reto Fiolka, an optical scientist at the University of Texas Southwestern Medical Center. “Our microscope is one tool that may bring us a deeper understanding of the molecular mechanisms that drive cancer cell behavior, since it enables high-resolution imaging in more realistic tumor environments.”


In their study, Fiolka and colleagues, including co-senior author Gaudenz Danuser, and co-first authors Meghan Driscoll and Erik Welf, also of UT Southwestern, used their microscope to image different kinds of skin cancer cells from patients. They found that in a 3D environment (where cells normally reside), unlike a glass slide, multiple melanoma cell lines and primary melanoma cells (from patients with varied genetic mutations) form many small protrusions called blebs.


One hypothesis is that this blebbing may help the cancer cells survive or move around and could thus play a role in skin cancer cell invasiveness or drug resistance in patients.


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Using Light To Control Protein Transport From Cell Nucleus With Light-Sensitive Protein

Using Light To Control Protein Transport From Cell Nucleus With Light-Sensitive Protein | Amazing Science | Scoop.it

Light can be used to control the transport of proteins from the cell nucleus with the aid of a light-sensitive, genetically modified plant protein. Biologists from Heidelberg University and the German Cancer Research Center (DKFZ) working in the field of optogenetics have now developed such a tool. The researchers, under the direction of Dr. Barbara Di Ventura and Prof. Dr. Roland Eils, employed methods from synthetic biology and combined a light sensor from the oat plant with a transport signal. This makes it possible to use external light to precisely control the location and hence the activity of proteins in mammalian cells. The results of this research were published in the journal “Nature Communications”.


Eukaryotic cells are characterised by the spatial separation between the cell nucleus and the rest of the cell. “This subdivision protects the mechanisms involved in copying and reading genetic information from disruptions caused by other cellular processes such as protein synthesis or energy production,” explains Prof. Eils, Director of Heidelberg University's BioQuant Centre and head of the Bioinformatics Department at Ruperto Carola and the DKFZ. Proteins and other macromolecules pass through the nuclear pore complex into and out of the cell nucleus in order to control a number of biological processes.


While smaller proteins passively diffuse through the nuclear pores, larger particles must latch onto so-called carrier proteins to make the trip. Usually short peptides on the protein surface signal the carriers that the protein is ready for transport. This signal is known as the nuclear localization signal (NLS) for transport into the nucleus, and the nuclear export sequence (NES) for transport out of the nucleus. “Artificially inducing the import or export of selected proteins would allow us to control their activities in the living cell,” says Dr. Di Ventura, group leader in Prof. Eils' department.


The Di Ventura lab has specialised in optogenetics, a relatively new field of research in synthetic biology. Optogenetics combines the methods of optics and genetics with the goal of using light to turn certain functions in living cells on and off. To this end, light-sensitive proteins are genetically modified and then introduced into specific target cells, making it possible to control their behaviour using light.


The recently published work reporting an optogenetic export system builds upon previous studies by other working groups investigating the LOV2 domain, which originally comes from the oat plant. In nature, this domain acts as a light sensor and, among other things, assists the plant in orienting to sunlight. The LOV2 domain fundamentally changes its three-dimensional structure as soon as it comes into contact with blue light, explains Dominik Niopek, primary author of the study.

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Room-temperature lithium metal battery closer to reality

Room-temperature lithium metal battery closer to reality | Amazing Science | Scoop.it

Rechargeable lithium metal batteries have been known for four decades to offer energy storage capabilities far superior to today's workhorse lithium-ion technology that powers our smartphones and laptops. But these batteries are not in common use today because, when recharged, they spontaneously grow treelike bumps called dendrites on the surface of the negative electrode.


Over many hours of operation, these dendrites grow to span the space between the negative and positive electrode, causing short-circuiting and a potential safety hazard.


Current technology focuses on managing these dendrites by putting up a mechanically strong barrier, normally a ceramic separator, between the negative and the positive electrodes to restrict the movement of the dendrite. The relative non-conductivity and brittleness of such barriers, however, means the battery must be operated at high temperature and are prone to failure when the barrier cracks.


But a Cornell team, led by chemical and biomolecular engineering professor Lynden Archer and graduate student Snehashis Choudhury, proposed in a recent study that by designing nanostructured membranes with pore dimensions below a critical value, it is possible to stop growth of dendrites in lithium batteries at room temperature. "The problem with ceramics is that this brute-force solution compromises conductivity," said Archer, the William C. Hooey Director and James A. Friend Family Distinguished Professor of Engineering and director of the Robert Frederick Smith School of Chemical and Biomolecular Engineering.


"This means that batteries that use ceramics must be operated at very high temperatures – 300 to 400 degrees Celsius [572 to 752 degrees Fahrenheit], in some cases," Archer said. "And the obvious challenge that brings is, how do I put that in my iPhone?" You don't, of course, but with the technology that the Archer group has put forth, creating a highly efficient lithium metal battery for a cellphone or other device could be reality in the not-too-distant future.


Archer credits Choudhury with identifying the polymer polyethylene oxide as particularly promising. The idea was to take advantage of "hairy" nanoparticles, created by grafting polyethylene oxide onto silica to form nanoscale organic hybrid materials (NOHMs), materials Archer and his colleagues have been studying for several years, to create nanoporous membranes.


To screen out dendrites, the nanoparticle-tethered PEO is cross-linked with another polymer, polypropylene oxide, to yield mechanically robust membranes that are easily infiltrated with liquid electrolytes. This produces structures with good conductivity at room temperature while still preventing dendrite growth. "Instead of a 'wall' to block the dendrites' proliferation, the membranes provided a porous media through which the ions pass, with the pore-gaps being small enough to restrict dendrite penetration," Choudhury said. "With this nanostructured electrolyte, we have created materials with good mechanical strength and good ionic conductivity at room temperature."

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New hack-proof RFID chips could secure credit cards, key cards, and goods in warehouses

New hack-proof RFID chips could secure credit cards, key cards, and goods in warehouses | Amazing Science | Scoop.it

Researchers at MIT and Texas Instruments have developed a new type of radio frequency identification (RFID) chip that is virtually impossible to hack. If such chips were widely adopted, it could mean that an identity thief couldn’t steal your credit card number or key card information by sitting next to you at a café, and high-tech burglars couldn’t swipe expensive goods from a warehouse and replace them with dummy tags.


Texas Instruments has built several prototypes of the new chip, to the researchers’ specifications, and in experiments the chips have behaved as expected. The researchers presented their research this week at the International Solid-State Circuits Conference, in San Francisco.


According to Chiraag Juvekar, a graduate student in electrical engineering at MIT and first author on the new paper, the chip is designed to prevent so-called side-channel attacks. Side-channel attacks analyze patterns of memory access or fluctuations in power usage when a device is performing a cryptographic operation, in order to extract its cryptographic key.


“The idea in a side-channel attack is that a given execution of the cryptographic algorithm only leaks a slight amount of information,” Juvekar says. “So you need to execute the cryptographic algorithm with the same secret many, many times to get enough leakage to extract a complete secret.”


One way to thwart side-channel attacks is to regularly change secret keys. In that case, the RFID chip would run a random-number generator that would spit out a new secret key after each transaction. A central server would run the same generator, and every time an RFID scanner queried the tag, it would relay the results to the server, to see if the current key was valid.


The researchers’ new chip uses a bank of 3.3-volt capacitors as an on-chip energy source. But it also features 571 1.5-volt cells that are discretely integrated into the chip’s circuitry. When the chip’s power source — the external scanner — is removed, the chip taps the 3.3-volt capacitors and completes as many operations as it can, then stores the data it’s working on in the 1.5-volt cells.


When power returns, before doing anything else the chip recharges the 3.3-volt capacitors, so that if it’s interrupted again, it will have enough power to store data. Then it resumes its previous computation. If that computation was an update of the secret key, it will complete the update before responding to a query from the scanner. Power-glitch attacks won’t work.


Because the chip has to charge capacitors and complete computations every time it powers on, it’s somewhat slower than conventional RFID chips. But in tests, the researchers found that they could get readouts from their chips at a rate of 30 per second, which should be more than fast enough for most RFID applications.


“In the age of ubiquitous connectivity, security is one of the paramount challenges we face,” says Ahmad Bahai, chief technology officer at Texas Instruments. “Because of this, Texas Instruments sponsored the authentication tag research at MIT that is being presented at ISSCC. We believe this research is an important step toward the goal of a robust, low-cost, low-power authentication protocol for the industrial Internet.”

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NASA engineers tapped to build first integrated-photonics modem

NASA engineers tapped to build first integrated-photonics modem | Amazing Science | Scoop.it

A NASA team has been tapped to build a new type of communications modem that will employ an emerging, potentially revolutionary technology that could transform everything from telecommunications, medical imaging, advanced manufacturing to national defense.


The space agency's first-ever integrated-photonics modem will be tested aboard the International Space Station beginning in 2020 as part of NASA's multi-year Laser Communications Relay Demonstration, or LCRD. The cell phone-sized device incorporates optics-based functions, such as lasers, switches, and wires, onto a microchip -- much like an integrated circuit found in all electronics hardware.


Once aboard the space station, the so-called Integrated LCRD LEO (Low-Earth Orbit) User Modem and Amplifier (ILLUMA) will serve as a low-Earth orbit terminal for NASA's LCRD, demonstrating yet another capability for high-speed, laser-based communications.


Since its inception in 1958, NASA has relied exclusively on radio frequency (RF)-based communications. Today, with missions demanding higher data rates than ever before, the need for LCRD has become more critical, said Don Cornwell, director of NASA's Advanced Communication and Navigation Division within the space Communications and Navigation Program, which is funding the modem's development.


LCRD promises to transform the way NASA sends and receives data, video and other information. It will use lasers to encode and transmit data at rates 10 to 100 times faster than today's communications equipment, requiring significantly less mass and power. Such a leap in technology could deliver video and high-resolution measurements from spacecraft over planets across the solar system -- permitting researchers to make detailed studies of conditions on other worlds, much as scientists today track hurricanes and other climate and environmental changes here on Earth.


The project, which is expected to begin operations in 2019, isn't NASA's first foray into laser communications. A payload aboard the Lunar Atmosphere and Dust Environment Explorer (LADEE) demonstrated record-breaking download and upload speeds to and from lunar orbit at 622 megabits per second (Mbps) and 20 Mbps, respectively, in 2013.



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A new technique for super-resolution digital microscopy using lens-free holograms

A new technique for super-resolution digital microscopy using lens-free holograms | Amazing Science | Scoop.it

Researchers from the California NanoSystems Institute at UCLA have created a new technique using lens-free holograms that greatly enhances digital microscopy images, which are sometimes blurry and pixelated.


The new technique, called “wavelength scanning pixel super-resolution,” uses a device that captures a stack of digital images of the same specimen, each with a slightly different wavelength of light. Then, researchers apply a newly devised algorithm that divides the pixels in each captured image into a number of smaller pixels, resulting in a much higher-resolution digital image of the specimen.


The research team was led by Aydogan Ozcan, Chancellor’s Professor of Electrical Engineering and Bioengineering at the UCLA Henry Samueli School of Engineering and Applied Science. The study appears in an open-access paper in the journal Light: Science and Applications, published by the Nature Publishing Group.


“These results mean we can see and inspect large samples with finer details at the sub-micron [nanoscale] level,” Ozcan said. “We have applied this method to lens-based conventional microscopes, as well as our lensless on-chip microscopy systems that create microscopic images using holograms, and it works across all these platforms.”


The benefits of this new method are wide-ranging, but especially significant in pathology, where rapid microscopic imaging of large numbers of tissue or blood cells is key to diagnosing diseases such as cancer. The specimens used in the study were blood samples, used to screen for various diseases, and Papanicolaou tests, which are used to screen for cervical cancer.


Ozcan said that wavelength scanning super-resolution works on both colorless and dye-stained samples. The entire apparatus fits on a desktop, so its size and convenience could be of great benefit to doctors and scientists using microscopes in resource-limited settings such as clinics in developing countries.


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Acoustic tweezers to manipulate cells could enable 3-D printing of cellular structures

Acoustic tweezers to manipulate cells could enable 3-D printing of cellular structures | Amazing Science | Scoop.it

Engineers at MIT, Penn State University, and Carnegie Mellon University have devised a way to manipulate cells in three dimensions using sound waves. These “acoustic tweezers” could make possible 3-D printing of cell structures for tissue engineering and other applications, the researchers say.


Designing tissue implants that can be used to treat human disease requires precisely recreating the natural tissue architecture, but so far it has proven difficult to develop a single method that can achieve that while keeping cells viable and functional.


“The results presented in this paper provide a unique pathway to manipulate biological cells accurately and in three dimensions, without the need for any invasive contact, tagging, or biochemical labeling,” says Subra Suresh, president of Carnegie Mellon and former dean of engineering at MIT. “This approach could lead to new possibilities for research and applications in such areas as regenerative medicine, neuroscience, tissue engineering, biomanufacturing, and cancer metastasis.”


The new acoustic tweezers are based on a microfluidic device that the researchers previously developed to manipulate cells in two dimensions. This device produces two acoustic standing waves, which are waves with a constant height. Where the two waves meet, they create a “pressure node” that can trap single cells. By altering the wavelength and another wave property known as the phase, the researchers can move the node and the cell trapped within it.


The research team previously used a similar approach to separate cancer cells from healthy cells, which could be useful for detecting rare tumor cells in a patient’s bloodstream and predicting whether the tumor will spread.

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From Four Strokes to the Design of a New Six-Stroke Engine

From Four Strokes to the Design of a New Six-Stroke Engine | Amazing Science | Scoop.it

Under the hood of almost all modern automobiles there sits a four-stroke internal combustion engine (ICE). Though the efficiency of the design has been improved upon significantly in the intervening years, the basic concept is the same today as that used by the first practical four-stroke engine built in the 1870s. During every cycle in a typical car engine, each piston moves up and down twice in the chamber, resulting in four total strokes… one of which is the power stroke that provides the torque to move the vehicle. But the automotive industry may soon be revolutionized by a new six-stroke design which adds a second power stroke, resulting in a much more efficient and less polluting alternative.


In a traditional ICE cycle, 1) the fuel/air valves open as the piston moves down, which draws air and fuel into the chamber; 2) the valves close as the piston moves back up, putting the air/fuel mixture under pressure; 3) the mixture is then ignited, causing a small explosion which forces the piston back down, which turns the crank and provides the torque; and finally 4) the exhaust valves open as the piston moves back up once again, pushing the byproducts of the fuel explosion out of the chamber. This leaves the piston back in its starting position, ready for another cycle. This process is repeated thousands of times per minute.


The clever new six-stroke design was developed by 75-year-old mechanic and tinkerer Bruce Crower, a veteran of the racing industry and a the owner of a company which produces high-performance cams and other engine parts. He had long been trying to devise a way to harness the waste heat energy of combustion engines, and one day in 2004 he awoke with an idea which he immediately set to work designing and machining. He modified a single-cylinder engine on his workbench to use the new design, and after fabricating the parts and assembling the powerplant, he poured in some gas and yanked the starter rope. His prototype worked.

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Switchable material could enable new memory chips

Switchable material could enable new memory chips | Amazing Science | Scoop.it

Two MIT researchers have developed a thin-film material whose phase and electrical properties can be switched between metallic and semiconducting simply by applying a small voltage. The material then stays in its new configuration until switched back by another voltage.


The discovery could pave the way for a new kind of “nonvolatile” computer memory chip that retains information when the power is switched off, and for energy conversion and catalytic applications.

The findings, reported in the journal Nano Letters in a paper by MIT materials science graduate student Qiyang Lu and associate professor Bilge Yildiz, involve a thin-film material called a strontium cobaltite, or SrCoOx.


Usually, Yildiz says, the structural phase of a material is controlled by its composition, temperature, and pressure. “Here for the first time,” she says, “we demonstrate that electrical bias can induce a phase transition in the material. And in fact we achieved this by changing the oxygen content in SrCoOx.”


“It has two different structures that depend on how many oxygen atoms per unit cell it contains, and these two structures have quite different properties,” Lu explains. One of these configurations of the molecular structure is called perovskite, and the other is called brownmillerite. When more oxygen is present, it forms the tightly-enclosed, cage-like crystal structure of perovskite, whereas a lower concentration of oxygen produces the more open structure of brownmillerite.


The two forms have very different chemical, electrical, magnetic, and physical properties, and Lu and Yildiz found that the material can be flipped between the two forms with the application of a very tiny amount of voltage — just 30 millivolts (0.03 volts). And, once changed, the new configuration remains stable until it is flipped back by a second application of voltage.


Strontium cobaltites are just one example of a class of materials known as transition metal oxides, which is considered promising for a variety of applications including electrodes in fuel cells, membranes that allow oxygen to pass through for gas separation, and electronic devices such as memristors — a form of nonvolatile, ultrafast, and energy-efficient memory device. The ability to trigger such a phase change through the use of just a tiny voltage could open up many uses for these materials, the researchers say.


Previous work with strontium cobaltites relied on changes in the oxygen concentration in the surrounding gas atmosphere to control which of the two forms the material would take, but that is inherently a much slower and more difficult process to control, Lu says. “So our idea was, don’t change the atmosphere, just apply a voltage.”


“Voltage modifies the effective oxygen pressure that the material faces,” Yildiz adds. To make that possible, the researchers deposited a very thin film of the material (the brownmillerite phase) onto a substrate, for which they used yttrium-stabilized zirconia.


In that setup, applying a voltage drives oxygen atoms into the material. Applying the opposite voltage has the reverse effect. To observe and demonstrate that the material did indeed go through this phase transition when the voltage was applied, the team used a technique called in-situ X-ray diffraction at MIT’s Center for Materials Science and Engineering.

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Revolutionary new graphene elastomer exceeds sensitivity of human skin

Revolutionary new graphene elastomer exceeds sensitivity of human skin | Amazing Science | Scoop.it

A new sponge-like material, discovered by Monash researchers, could have diverse and valuable real-life applications. The new elastomer could be used to create soft, tactile robots to help care for elderly people, perform remote surgical procedures or build highly sensitive prosthetic hands.


Graphene-based cellular elastomer, or G-elastomer, is highly sensitive to pressure and vibrations. Unlike other viscoelastic substances such as polyurethane foam or rubber, G-elastomer bounces back extremely quickly under pressure, despite its exceptionally soft nature. This unique, dynamic response has never been found in existing soft materials, and has excited and intrigued researchers Professor Dan Li and Dr Ling Qiu from the Monash Centre for Atomically Thin Materials (MCATM).


According to Dr Qiu, "This graphene elastomer is a flexible, ultra-light material which can detect pressures and vibrations across a broad bandwidth of frequencies. It far exceeds the response range of our skin, and it also has a very fast response time, much faster than conventional polymer elastomer.


"Although we often take it for granted, the pressure sensors in our skin allow us to do things like hold a cup without dropping it, crushing it, or spilling the contents. The sensitivity and response time of G-elastomer could allow a prosthetic hand or a robot to be even more dexterous than a human, while the flexibility could allow us to create next generation flexible electronic devices," he said.


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Revolutionary new graphene elastomer exceeds sensitivity of human skin

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Seeing where energy goes may bring scientists closer to realizing nuclear fusion

Seeing where energy goes may bring scientists closer to realizing nuclear fusion | Amazing Science | Scoop.it

An international team of researchers has taken a step toward achieving controlled nuclear fusion--a process that powers the Sun and other stars, and has the potential to supply the world with limitless, clean energy. The team, led by scientists and engineers at the University of California, San Diego and General Atomics, developed a new technique to "see" where energy is delivered during a process called fast ignition, which is an approach to initiate nuclear fusion reactions using a high-intensity laser. Visualizing the energy flow enabled researchers to test different ways to improve energy delivery to the fuel target in their experiments. The researchers published their findings online in the Jan. 11 issue of the journal Nature Physics.


Fast ignition involves two stages to start nuclear fusion. First, hundreds of lasers compress the fusion fuel (typically a mix of deuterium and tritium contained in a spherical plastic fuel capsule) to high density. Then, a high-intensity laser delivers energy to rapidly heat (ignite) the compressed fuel. Scientists consider fast ignition a promising approach toward controlled nuclear fusion because it requires less energy than other approaches.


But in order for fast ignition to succeed, scientists need to overcome a big hurdle: how to direct energy from the high-intensity laser into the densest region of the fuel. "This has been a major research challenge since the idea of fast ignition was proposed," said Farhat Beg, professor of mechanical and aerospace engineering and director of the Center for Energy Research at UC San Diego.


To tackle this problem, the team devised a way to see, for the first time, where energy travels when the high-intensity laser hits the fuel target. The technique relies on the use of copper tracers inside the fuel capsule. When the high-intensity laser beam is directed at the compressed fuel target, it generates high-energy electrons that hit the copper tracers and cause them to emit X-rays that scientists can image.


"Before we developed this technique, it was as if we were looking in the dark. Now, we can better understand where energy is being deposited so we can investigate new experimental designs to improve delivery of energy to the fuel," said Christopher McGuffey, assistant project scientist in Beg's High Energy Density Physics Group at the UC San Diego Jacobs School of Engineering and co-author on the paper.


And that's what the team did. After experimenting with different fuel target designs and laser configurations, researchers eventually achieved a record high (up to 7 percent) efficiency of energy delivery from the high-intensity laser to the fuel. This result demonstrates an improvement on efficiency by about a factor of four compared to previous fast ignition experiments, researchers said.


Computer simulations also predicted an energy delivery efficiency as high as 15 percent if the experimental design was scaled up. But this prediction still needs to be tested experimentally, said Beg. "We hope this work opens the door to future attempts to improve fast ignition."


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Programmable Material Algorithm Solves Universal Coating Problem

Programmable Material Algorithm Solves Universal Coating Problem | Amazing Science | Scoop.it
The world is full of complex structures such as bridges, roads, wind turbines, power stations, and so on, that have to be carefully monitored to ensure their integrity.

Today, much of this work has to be done by engineers on the spot. That’s not so easy for objects that span hundreds, or even thousands, of kilometers, such as roads, or remote structures such as offshore wind turbines.

So a way of doing this remotely would be hugely valuable. Clearly it requires some kind of independent sensor that can measure the required property such as temperature or acidity, or cracking, and so on.

And indeed there are numerous gadgets for doing this. For example, optical fibers attached to or embedded in objects can measure the forces acting on it and sensors attached to these fibers can monitor temperature, acidity, and so on.

But these kinds of sensors do not provide global coverage—they cannot tell you the temperature at any point on the object. For that you need something more ambitious.

The dream would be to have a smart coating that does this job. This would be a “programmable material” that entirely coats an object in a thin layer. It would contain tiny particulate sensors that gather information about the surface, such as its temperature, and communicate it to their nearest neighbors.

While mathematicians have long pondered the properties of programmable materials, one question has stumped them. Is it possible to use a smart coating to determine the temperature at any point on an arbitrary object, even though the sensors have no knowledge of its overall geometry?

Today, we get an answer to this question thanks to the work of Zahra Derakhshandeh at Arizona State University in Tempe and a few pals. They’ve developed a series of algorithms that provide the mathematical framework that allows these particles to solve this problem.
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