Science & Technology News (698)
Posted: November 21, 2014 07:09AM
They say one should not judge a book by its cover, but sometimes the cover is the most interesting part. Topological insulators (TIs) are a curious class of materials that conduct electricity on their surfaces, but not through their bulk. Researchers at Purdue University have recently found that they also possess another property that should prove useful in future applications of TIs.
Due to the different properties between a topological insulator's bulk and surface, electrons can have some odd behaviors. Among these is that electrons on the surface are always spin polarized, unlike in other materials where the spins can be random and cancel each other out. This is one of multiple special properties that could see TIs used for spintronics and quantum computers. What the Purdue researchers have found is that the electrical resistance of the material is not dependent on its thickness. This is not normally the case with other three-dimensional materials, but here it is. They also found that the conduction seemed to be topologically protected, which would help it maintain conductance as thickness decreases.
It is because of this protection and the ability to conduct electrons without disrupting their spin states that could allow TIs to be made into spintronic and quantum computers. Such computers would operate very differently from modern computers and potentially allow for much more complicated operations to be performed very quickly.
Source: Purdue University
Posted: November 20, 2014 03:32PM
It is not uncommon for academics at universities to form spinout companies based on their research. One example is QD Vision, which is an MIT spinout that works with quantum dot displays. Thanks to partnerships with other companies, QD Vision's technology may soon be coming to the world.
Quantum dots are semiconductor nanocrystals that can be tuned to react to and emit specific colors of light. This ability to directly emit light is part of why many want to see them used in televisions, and thanks to Sony and TCL, some televisions are already using the spinout's Color IQ technology. Traditional LCD TVs place a white LED backlight behind red, green, and blue filters to produce colors on the screen. The problem is that the LED backlight is not actually white but blue; a phosphor is used to create the white light, which causes some of the light to be lost. Color IQ has a different approach as it uses the blue backlight, without a phosphor, to energize quantum dots to produce red and green. The result is a display that covers 50% of the NTSC color gamut while being 20% more efficient.
Compared to OLED displays, the Color IQ displays are just as colorful, but significantly cheaper to produce. Currently the quantum dot displays using QD Vision's technology are only available in Chine, but they are expected to come to the rest of the world in mere months.
Posted: November 20, 2014 07:02AM
Because of their efficiency, many want to see white LEDs used to light our homes, but while they do use less power, they are also less warm. White LEDs do not actually produce white light but instead emit blue light that energizes a phosphor, which then produces the white light. The resulting light has a cooler, blue tint to it, but researchers at the Eindhoven University of Technology, as reported in Optics Express have found a way to create a warmer tone, when LEDs are dimmed.
Others have created LED systems that produce a warm color when dimmed by using multiple LEDs that mix their colors. These systems are rather complicated though, as control circuitry has to be used to make sure the many components work correctly together. The Eindhoven researchers' approach however is simpler as it just changes the phosphor used. This new phosphor is a composite of a liquid crystal and polymeric material, which makes it sensitive to temperature. At higher temperatures it is transparent, allowing the cooler, blue light of the LED to come through, but at lower temperatures, when the LED is dimmed, it scatters light. This causes more of the blue light to stay in the phosphor, creating a warmer glow.
Generally, humans prefer warmer, redder light in low-light situations and that may have to do with the color of the Sunrise and Sunset. By having LEDs produce a warmer light when dimmed, the technology could become more acceptable in homes. The researchers predict that products using their design could reach the market in just two years, if they are proven reliable.
Source: The Optical Society
Posted: November 19, 2014 02:16PM
They say the family that plays together, stays together as a result of the interactions between family members. Researchers at Concordia University have found that this remains true for social networking games, as it did for traditional board games.
With many families spread across countries and even continents, staying connected can be difficult, which is why many have turned to social networks and some to social networking games (SNGs). To examine the impacts SNGs have had on families, the Concordia researchers gave questionnaires to a group of social network gamers and followed them up with interviews. They found that the games actually improved quality of time family members spent together, even if the games lack direct communication or had asymmetrical multiplayer. The reason for this is that the games gave a common topic to discuss. The researchers also found that this was not limited to younger generations, as grandparents were playing with grandchildren.
Naturally the researchers see this as a means for families to stay connected, but they also recognize that this is something game designers could take advantage of. Families connecting through a game are more likely to keep playing, and extend the life of the games more than playing with strangers or even friends.
Source: Concordia University
Posted: November 19, 2014 06:03AM
It is always nice when a tool has multiple uses as it can simplify work and even make new things possible. This is no less true in medicine but in that field, it can be more difficult to achieve than adding a saw blade to a knife. Researchers at MIT though have developed a nanoparticle that works for both MRI and fluorescent imaging, and could give new insight into a patient's cancerous and healthy tissue.
The nanoparticles are made from polymer chains that have either an MRI contrast agent or fluorescent molecule attached. The contrast agent is a nitroxide and 99% of the polymer chains have this attached to it, while the fluorescent molecule is called Cy5.5 and is attached to the remaining one percent. Normally, the nitroxide will hide the Cv5.5 but can be deactivated by grabbing electrons from other molecules. For the researchers' tests in mice, this other molecule was vitamin C and as that is produced in the liver, that organ would fluorescence but had no MRI signal. The brain also had some fluorescence, as that is a destination of the vitamin C, but the blood and kidneys had maximal MRI contrast, due to the low concentrations of vitamin C present there.
The researchers also created nanoparticles that can carry up to three separate drugs, allowing them to monitor if the drugs are reaching their intended target. These nanoparticles have tremendous diagnostic capability by enabling doctors to follow disease progression in a patient, in real-time.
Posted: November 18, 2014 11:06AM
Many a long time the idea of life and liquid water on Mars has intrigued humanity. To look at it now, we can see it is dry and arid, but we have also learned that it likely did once have water flowing over its surface. Now researchers at Brown University and the Weizmann Institute of Science are suggesting that these warm periods, when water might have flowed, were episodic and based on the planet's volcanism.
Part of the reason Mars is dry today is because it is too cold to support liquid water. Some believe that it may have supported it billions of years ago, but that long ago, the Sun was dimmer, so where would the heat have come from? What the researchers suggest is that periods of volcanic activity may have triggered temporary warming periods, allowing water to form around the equator. This would be the opposite of what we see on Earth though, as volcanos typically cool our planet, but then our atmosphere is very different from that of Mars. The red planet has a dusty atmosphere, and the sulfuric acid released by volcanism could have caused the dust to clump up, allowing more light to strike the surface, while sulfur dioxide may also have kept some of the heat from escaping.
If this theory is correct, one of the implications is that the planet likely only enjoyed these warm periods for decades or centuries at a time. That may not seem like much time, but it is still possible that life could have formed and bloomed during those periods, in which case we may have a better idea of where to look for any fossil remnants.
Source: Brown University
Posted: November 18, 2014 07:08AM
Many of our modern devices rely on electronics that perform operations based on the charge of electrons. In the future, electronics may be replaced by spintronics, which use a different property of electrons, but much must be done before that future can be achieved. Researchers at New York University and the University of Barcelona have recently succeeded in creating and controlling spin waves in a way that is bringing that future a little closer.
Instead of relying on the charge of electrons, spintronics use their spin, which is an intrinsic property tied to magnetism. This allows spintronics to potentially be much more efficient, as spin waves do not have to possess a certain amount of energy to be readable. Producing and controlling spin waves is not easy though, at least not when the target is waves that will be useful for advanced devices. Ideally these waves will have short wavelengths, which are what the researchers have managed to create by injecting spin-polarized currents into magnetic materials, using nanoscale contacts. That made the waves short, but by combining magnetic forces they were also able to confine the spin waves into magnetic droplets that remained still, instead of propagating out.
By controlling these droplets, it could one day be possible to emit spin waves on demand, with information encoded in them.
Source: New York University
Posted: November 17, 2014 02:16PM
Superconductors are amazing materials that could one day revolutionize the world by allowing the electrons to flow without resistance. That day has not yet come though, because materials only become superconducting at low temperatures. While investigating one, researchers at Linköping University discovered it undergoes a process that could upset our understanding of superconductivity in this and similar superconductors.
The superconductor in question is YBa2Cu3O7-x, or YBCO, which is a ceramic copper-based material that becomes superconducting at -183 ºC. Since it was first discovered, researchers have known it was odd because it consists of two planes of copper oxide, with separate chains of copper oxide between them. Exactly what role these chains played has been unknown for years, but it had been discovered that varying the oxygen doping of the chains, influences the critical temperature of the material. Using X-ray absorption spectroscopy and resonant inelastic X-ray scattering, the researchers found that the material undergoes self-doping, whereby positively charged holes are supplied to the copper oxide planes from the chains, when cooled.
This had not been observed before in this material and will almost certainly change our understanding of how superconductivity arises in many copper-based high-temperature superconductors. Normally a constant doping level is assumed, but this no longer appears to be the case.
Posted: November 17, 2014 09:05AM
At this point, QR codes are practically part of day-to-day life, sending us information and links with our smartphone cameras. While they already have many uses, one would probably not expect the next use they may have. Researchers at the University of Connecticut, as reported in The Optical Society's Optica journal, have developed a way to store 3D information in QR codes, and to do so securely.
Many people probably do not think about it, but QR codes can actually be dangerous as many scanners will just open the links the codes contain, and those sites may contain malicious code. This is because those QR codes only contain the web address and nothing else. The system the researchers developed however, keeps some of the data in the code, so an Internet connection is not needed. The data is actually a portion of a 3D image, made from multiple 2D images, and broken into parts. By scanning multiple codes in sequence, a phone can collect all of the data and reconstitute the original, 3D image.
The process is a bit more complicated than that though, as the data in the codes is also encrypted and compressed, so the scanner will need the proper key to decrypt it. Modern smartphones are capable of this though, so the researchers see a future where these QR codes are used to securely share 3D information using standard smartphone technologies.
Source: The Optical Society
Posted: November 17, 2014 06:29AM
Malware is a problem for everyone with a computer device that connects to any other. With the right attack, popular and important services can be taken down and private information can be stolen, which makes protection systems very important. Researchers at the University of Utah have recently created a new tool that not only protects against malware, but can repair the damage, and learns to block it in the future.
Advanced Adaptive Applications, or A3, was designed to protect virtual machines by continually scanning its operations with stackable debuggers. These are multiple debugging tools that all run on top of each other, to watch what a virtual machine is doing and catch any errant behavior. When it does, it will stop the virus or attack, and then approximates a repair for the software code that was affected. It also learns to prevent the issue from happening again. All of this it does in just minutes and without disrupting servers.
The researchers have already demonstrated A3 with the Shellshock attack, and succeeded in stopping the attack and repairing the damage in just four minutes. It was designed to run on systems using a version of Linux and was funded by DARPA, but being open source, the researchers believe that it could be adapted into commercial products at some point.
Source: University of Utah
Posted: November 14, 2014 06:25PM
Taste is such an important sense as it can let us know to avoid spoiled foods and more. Naturally, some have been working to replicate this sense electronically, for use as a chemical sensor. As reported in the journal ACS Applied Materials & Interfaces, a group of researchers have succeeded in creating such a sensor that is both highly sensitive and cheap.
Electronic tongues mimic real tongues by having a great many, small sensors on them that detect different substances, and then report back what they have. What sets this e-tongue apart from others is that it has a silicon base, which will make it easier to connect to other, silicon-based electronics. So far they have tested it with water, whiskey, cognac, and Armagnac and it did provide distinct signatures for each.
Already artificial tongues are used to check the quality of different foods, but this device could have more uses beyond that. The researchers specifically designed it to have potential applications in medicine for diagnostics and drug testing, as well as environmental monitoring on top of food testing.
Source: American Chemical Society
Posted: November 14, 2014 10:05AM
One of the many goals of the Large Hadron Collider at CERN was to discover the Higgs boson, a long sought-after particle that would fit a gap in the Standard Model. In 2012, researchers identified a new particle in an energy range that the Higgs particle may exist at. While many took this to mean that it was indeed the Higgs boson that was found, there is not yet enough evidence to prove that, and now researchers at the University of Southern Denmark are expanding on that.
The Standard Model is the theory currently used to explain particle physics and has had known issues for some time. Among these is a lack of an explanation for mass, which is what the Higgs boson is supposed to explain. Study of the Standard Model has allowed the properties of the particle to be approximated, including its energy value, which is why many believe the LHC found it. What the Southern Denmark researchers point out in their study though is that the math is not conclusive evidence that the Higgs boson was actually discovered, but that a different particle may have been. Specifically they suggest it may have been a techni-higgs particle, which would rock a great deal of the scientific world.
The techni-higgs particle is like the Higgs boson, but has some important differences, including not being an elementary particle. It would actually be made of techni-quarks, which are believed to be elementary. If it turns out that this is what was discovered, which the researchers believe is equally likely, it would lead to a massive change to science as techy-quarks are likely bound together by what is called the Technicolor force, and not one of the four known fundamental forces (gravity, electromagnetism, weak nuclear force, and strong nuclear force).
Posted: November 14, 2014 06:14AM
In general, the smaller an object is, the more fragile it is, so when working with atom-thick sheet, you can expect it to be very fragile. Such fragility has proven to be a problem for thin semiconductors when trying to transfer them to flexible materials. Researchers at North Carolina State University however, have devised a method to very simply separate molybdenum sulfide from one substrate to another, without wrinkling or cracking it.
Molybdenum sulfide (MoS2) is an inexpensive semiconductor and has optical and electrical properties similar to other semiconductors. Being a thin film just an atom thick though, does give it the advantage of being flexible, but it cannot be made on a flexible substrate. The manufacturing process is too hot for a flexible substrate to survive, so the MoS2 has to be transferred. Current methods require chemical etching, but the chemistry can damage the film, but the researchers have a much safer and faster method. The substrate the thin film is grown on, and attached to, is made of sapphire, which is hydrophilic, while the MoS2 is hydrophobic. By placing a drop of water on the thin film and poking its edge with tweezers or a scalpel, the water will actually move between the materials, peeling them apart.
Chemical etching normal requires hours to separate the materials, while this method is done in just minute. With this method being so much simpler and faster, it could be used to bring MoS2 to future, flexible devices.
Source: North Carolina State University
Posted: November 13, 2014 02:10PM
Though you may not realize it, atomic clocks are important to your daily life in a number of ways. Without them, distributed systems, such as cell networks, cable networks and GPS, could collapse as the many parts fall out of synchronous with each other. Currently the most accurate atomic clocks are about the size of a room, making them hard to move to areas you may need accurate time, but researchers at MIT may be changing that soon.
Atomic clocks work by measuring the oscillations of atoms between two states, and room-sized fountain clocks achieve this by passing clouds of cesium atoms through microwave beams. Creating microwave beams requires somewhat large equipment though, which is why these clocks are so large. Optical lasers are much smaller and could be used, except that the laser's electric field could shift the oscillation frequency over time. To solve this problem, the researchers vary the frequency and intensity of the laser. The result is a miniature fountain clock that could potentially be the size of a Rubik's cube.
These smaller atomic clocks will not be as accurate as their big brothers, but will still be more precise than the chip-sized atomic clocks currently available, by only drifting over a day or a week. That may not seem like long, but in areas GPS signals, transmitting accurate times can be lost, like underwater, indoors, or in militarily hostile environments, that could be just what is needed.
Posted: November 13, 2014 09:59AM
Connections are critical in life and in physics, as the interface or boundary between materials can have some special properties. Recently, with the discovery of 2D materials, many have been wondering about what happens at the one-dimensional boundaries between two of these materials. Now researchers at ORNL have managed to actually see these boundaries and analyze some of their properties.
The two materials used for this are graphene and hexagonal boron nitride, which researchers only learned to grow together in a single layer, earlier this year. To see the 1D boundary between the materials, the researchers had to use scanning tunneling microscopy, spectroscopy, and density-functional calculations. This combination allowed them to observe spatial and energetic distributions along the boundary. What they found was a very confined electric field, which allowed them to observe a polar catastrophe. This phenomenon is known to occur in 3D oxide interfaces and involves atoms and electrons reorganizing themselves in response to an electrostatic field. That field is produce from the materials having different polarities.
Beyond improving our knowledge of 1D interfaces this research could lead to some real-world applications. One dimensional electron chains could be used to carry current in ultra-thin or flexible devices.
Source: Oak Ridge National Laboratory
Posted: November 13, 2014 07:10AM
Optical data transmission can be tricky as you have to make sure the frequency used will not interfere with other transmissions, destroying the data. One way around this is to use different polarizations of light, which traditionally had limitations, but thanks to orbital angular momentum, those limits are disappearing. Now researchers from Austria have successfully transmitted 16 streams of data using the same frequency, 3 Km across Vienna.
Optical polarization is the orientation a wave oscillates in, and examples would be vertical, horizontal, and circular. In 1992, researchers first started investigating orbital angular moment (OAM), which can be used to have light waves spiral like a corkscrew. As light can theoretically be made to have infinitely many twists in it, infinitely many channels could use the same frequency of light. In this case the researchers only used 16 different twist patterns to transmit images. Before the images could be sent the 3 Km across Vienna though, the researchers had to test the light beams and used an artificial neural network to filter out the disturbances from air turbulence.
Obviously this research, especially the method for countering disturbances, is important for future, wireless transmission technologies, by allowing for tremendously greater bandwidth. It could also be used for quantum communication though, as each photon could carry more information than just spin or polarization, but also an OAM number.
Source: Institute of Physics
Posted: November 12, 2014 05:21PM
Author: Brentt Moore
NVIDIA has officially released its Apollo 11 GeForce demo to the public, which allows owners of Maxwell-powered GeForce GTX GPUs to discover that the photograph of the Apollo 11 landing is in fact genuine and authentic. This release comes roughly two months after NVIDIA showed off its software at GAME24, which created quite a stir amongst conspiracy theorists. The Apollo 11 GeForce demo utilizes Epic’s Unreal Engine 4, the new Maxwell GPU architecture, and VXGI real-time global illumination to create a virtual environment that debunks the conspiracy theory of the photograph being faked by NASA.
Interested owners of Maxwell-powered GeForce GTX GPUs can download the Apollo 11 GeForce demo immediately from the NVIDIA website, with more information about the demo available on the company’s blog.
Source: Press Release
Posted: November 12, 2014 11:11AM
Science fiction has taught us the thought-controlled technologies can be pretty awesome, as devices react to our wishes instantaneously. I wonder how many sci-fi story tellers ever thought that gene expression would be something controlled by the mind. That is exactly what researchers at ETH Zurich have achieved though.
Gene expression is the process of using the information stored in genes to generate proteins. In this case, the researchers were working with SEAP, which is an easily detected human model protein, and had it produced by cell cultures by implants in mice. Besides the cell cultures, the implant also possessed an LED that would light up the culture, which is what directly controlled the gene expression. Electroencephalograms (EEGs) of test subjects were used to control the LED, with different states of mind causing different amounts of SEAP to be produced. When the subjects were concentrating, the mice contained normal levels of the protein, but when they were meditating, the levels spiked. The subjects were also allowed to observe the LED and were able to consciously control the LED, switching it on and off.
The applications for this research naturally include implants that could be used to treat neurological diseases such as chronic headaches, back pain, and epilepsy. Just by detecting certain brainwaves with an EEG, an implant could quickly respond and provide treatment for the issue, at the onset.
Source: ETH Zurich
Posted: November 12, 2014 06:34AM
A product of many power plants is heat, and naturally this heat has to be removed from the plant for it t continue operating. Currently water from a river or lake is used to remove the heat, with US power plants using almost triple the amount of water that goes over Niagara Falls every minute. Researchers at the University of Kansas have an idea for changing this, and were recently awarded an NSF grant to develop it.
The idea is to bring the heatpipes or thermosyphons used in computers to power plants. Instead of having an open system with water running in and back out of the power plant, the researchers want intend to design a closed system that will have a fluid, possibly water, constantly moving through it by convection, transporting heat away from the plant. The researchers are not sure yet how the heat will be transferred to the air though, but are considering fins and metal foams for the role.
Currently the researchers are devising the equations and models to describe the physics. They predict that new cooling systems, including those they are working on, could be commercialized inside of ten years.
Source: University of Kansas
Posted: November 11, 2014 10:32AM
Though most solar cells we are familiar with today rely on silicon, many groups around the world are developing solar cells based on polymers. The change in material can allow for a number of advantages, including drastically reduced costs. Researchers at North Carolina State University and Hong Kong University of Science and Technology have recently found a new way to produce polymer solar cells more cheaply while also setting a new efficiency record.
To create this variety of polymer solar cells, one starts with a mixture of a polymer donor and a fullerene acceptor, to which a solvent is added until the mix becomes a liquid. At this point the liquid is spread out on a surface, and once the solvent evaporates, the liquid solidifies, leaving clumps behind. The researchers discovered that the size of these clumps impacts the efficiency of the solar cell, and that these sizes are temperature dependent. The researchers also substituted many of the fullerenes to push the efficiency to 10.8%, past the published 9.8% record.
While this control over efficiency is definitely important, the researchers also found that this efficiency could be achieved in thick films. This means that mass production methods, such as slot die casting and roll-to-roll processing, can be used to, as opposed to this with special thickness control.
Source: North Carolina State University
Posted: November 11, 2014 06:41AM
Talking over someone can be problematic as it makes it difficult for you, or anyone, to hear what is being said. A similar problem exists for wireless technologies, as multiple transmissions cannot be sent and received on the same frequency at the same time. At least, it cannot be done without a radio wave circulator, and now researchers at the University of Texas at Austin have developed a new circulator that could one day fit in our cellphones.
Radio wave circulators work by breaking the symmetry of wave transmission and traditionally have relied on magnetics to do so. These magnets come with the cost of increased size, keeping the devices out of many technologies, and weighing down others. The Texas researchers however have created a smaller radio wave circulator that instead uses a traveling wave, spinning around their device. The prototype they built is just two centimeters wide, but it could potentially be brought down to just microns in size, making integration into smartphones a possibility, especially as it is made of components already found in circuit boards.
By removing the need for larger magnets, this technology could help bring full-duplex functionality to many devices, which means they would be able to transmit and receive on the same frequency, at the same time. This would dramatically improve connection qualities and speeds, without having to use more of the wireless spectrum.
Source: University of Texas at Austin
Posted: November 10, 2014 02:21PM
Electronics currently dominate information processing, as all computers rely on them, but for high-speed data transmission, optics are often used for their unbeatable speed. These two technologies do not always play well together, because of the necessary conversion devices. Researchers at the Universities of Surrey, Cambridge, and Southampton have recently discovered how to create pn-junctions in a commonly used glass, which could bring these two technologies closer together than they ever have been.
Amorphous chalcogenides are a kind of glass that are used in CDs and DVDs, because some of them will undergo a phase change from heat. What the researchers found is that it is possible to ion dope them. Such doping would allow for the conduction and control of electrons and positive holes in the material, and even the creation of pn-junctions. Along with the optical properties of the glass, the material could be made into a light source, detector, and guide.
By bringing electronics and optics to the same material, it could be used bring optical information directly to computers, and possibly even all-optical systems. The researchers predict the results of this research could be in computers within ten years.
Source: University of Surrey
Posted: November 10, 2014 08:59AM
Electric cars rely on batteries to deliver the power needed to drive around, and while batteries work well for distance, they are less-than ideal for acceleration. Supercapacitors however offer the needed burst for acceleration, but lack the storage potential. Researchers at Queensland University of Technology have recently created a supercapacitor film that can be integrated into car panels, allowing a vehicle to have the advantages of both technologies.
Supercapacitors store energy in the electric field between two electrodes, which allows for rapid charging and discharging, unlike the chemical processes of batteries. That means that supercapacitors can push out the power needed to get a car up to speed and can then be charged in minutes, instead of hours. By integrating them into car panels, which cover a lot of area, the supercapacitors could store enough energy to charge the car's batteries in a matter of minutes. As the energy density of supercapacitors increase and potentially surpass that of batteries, we could see electric cars with ranges of 500 Km, which is comparable to modern, gasoline powered cars.
The researchers predict that their supercapacitor panels could be on cars inside of five years, but it may not just be cars that will use them. Supercapacitor films could also be added to smartphones, allowing them to charge much quicker than batteries allow.
Posted: November 10, 2014 05:44AM
Back in April a vulnerability was discovered in OpenSSL called Heartbleed. This security flaw made it possible for the memories of vulnerable systems to be accessed by anyone. Naturally website administrators were quick to patch their software and remove the flaw, but researchers at the University of Maryland, Northeastern University, and Stanford University have found that they did not do enough.
There were threes to ensuring a website was secured and back under the control of the administrator. The first was obviously to deploy the software fix and 93% of administrators did so within three weeks. The other two steps were to revoke security certificates and issue new ones. According to the researchers, only 13% did both of these steps. Those certificates ensure visitors are going to the authentic site and not something an attacker put up, which is why it is necessary to revoke the certificates that may have been comprised.
The researchers also found that the number of certificate revocations dipped over weekends, displaying the human factor in website security. While these are definitely serious issues, the researchers see this study as an opportunity to improve website security in the future.
Source: University of Maryland
Posted: November 7, 2014 02:01PM
It is not uncommon in certain fields of science to make observations, take measurements, and then explain the data with theories. Sometimes the theories do not fully explain the data though, which means more data needs to be collected and potentially new theories be developed. Researchers at the California Institute of Technology have recently found that the cosmic infrared background (CIB) does not quite match what galaxies would produce.
Like the cosmic microwave background, the CIB is a glow that can be observed in all directions, but it is difficult to spot. Earth's atmosphere blocks infrared light, so measurements have to be taken from satellites or suborbital rockets, and the Sun heats up gases in the Solar System, creating the Zodiacal light. The Caltech researchers were able to overcome both of these challenges for the CIB Experiment (CIBER) though, and built a map of the CIB that showed large and bright fluctuations. Originally they were hoping to catch light from the first stars and galaxies but that does not fit the observations, as that light should be redder, due to hydrogen absorbing it. Instead they found very bright and blue light, which would make sense if it were coming from stars that had been ejected from galaxies, and now exist in the space between them.
While that theory does fit the measurements well, it is not perfect, as the light is still too blue to match the theory. If these stars are the source though, it should be possible to catch them around their parent galaxies, so the researchers are planning a new experiment to hopefully spot them in those areas.
Posted: November 7, 2014 10:05AM
For many people, cockroaches are probably one of the more horrible organisms to exist, for one reason or another. However, someday these insects may actually be put to use finding disaster survivors thanks to efforts making them into cyborgs, or biobots. Now researchers at North Carolina State University have given biobots microphones for hearing the sounds of trapped persons and then actually finding them.
The cockroaches wear small, electronic backpacks that are capable of controlling the insects' movements. One version of these backpacks has a single, omnidirectional microphone that can capture sounds in high resolution. These sounds can then be transmitted to first responders, in order to determine if the sounds are of people or have less important sources. The other backpack is equipped with three, directional microphones, which would be used to track and seek out the source of a sound, which the researchers have already demonstrated.
Along with using the microphones to find the sources of sounds, the researchers have also shown that the biobots can be held within invisible fences. These fences could be used to keep the biobots in a disaster site, within range of each other for wireless transmission, or near light sources, in order to recharge the electronics.
Source: North Carolina State University
Posted: November 7, 2014 05:52AM
The Large Hadron Collider is a massive structure with the ability to accelerator particles to very high energy, in order to smash them together. One of its successors though could be small enough to fit in the basements of many buildings, including hospitals and universities. This possibility is thanks to researchers at SLAC National Accelerator Laboratory and the University of California, Los Angeles.
First envisioned over thirty years ago, plasma wakefield acceleration is very different from more traditional accelerator designs. Instead of using massive magnets and radio waves to energize particles, plasma wakes are created to push and carry electrons to great speeds over very short distances. The design the SLAC researchers built uses two bunches of electrons, fired into a lithium gas. The first bunch of electrons strips away the lithium's electrons, creating the plasma. These excited electrons then try to fall back down in energy, and do so behind the second electron bunch, propelling it to very high energies.
Plasma wakefield acceleration has many advantages including great efficiency. In just 20 feet, the researchers were able to accelerate an electron beam to the same energies as the 2-mile-long SLAC linear accelerator. More work will have to be done before these practically tabletop accelerators can compete with their larger cousins, including controlling the shape of the second electron bunches, to make sure the resulting electron beam is of the highest quality.
Posted: November 6, 2014 04:13PM
The ability to peer inside of something has been a mainstay of many works of fiction, and a necessity for many medical procedures. Peering inside a patient is not exactly easy though, with some technologies for doing so being quite massive. As reported in The Optical Society's Optics Express journal, researchers in the Netherlands and France have created a new, compact tool that combines ultrasound and photoacoustic imaging.
Ultrasound, as most people likely know, bounces sound waves off of body parts and creates an image based on the echoes. Photoacoustics also uses ultrasound, but generates the waves very differently. Light is used to heat up tissue inside the body, and that small change in temperature causes a change in pressure. The pressure changes are what produce the ultrasound waves, which are then collected and analyzed. Unlike many other methods, photoacoustics can capture information, such as the sub-millimeter networks of blood vessels and the presence of hemoglobin, and when combined with spectroscopic measurements, the oxygen saturation of hemoglobin in single vessels can even be measured.
The key to fitting this technology down to the size of a stapler and a computer monitor was the stack of diode lasers that generate higher energies than diodes have achieved before. The researchers are working on commercializing their work and to expand it to multi-wavelength imaging, as currently it is limited to the near infrared.
Source: The Optical Society
Posted: November 6, 2014 11:17AM
To hold graphite and diamond in your hands, you would not expect the two are allotropes of the same element. Graphite is very soft while diamond is among the hardest materials known to exist. Researchers at Purdue University have now found a way to create diamond patterns on graphite that could have many applications.
Originally the researchers were investigating ways to strengthen metals with a layer of graphite, layer of glass, and a nanosecond-pulsing laser. It was then that they noticed the black graphite seemed to disappear. Investigation revealed the graphite had been converted to clear diamond. What had happened was the laser pulses created a graphite plasma, and the layer of glass kept the plasma from escaping. When the plasma cooled and solidified, it turned to diamond instead of graphite.
Normally high temperatures and pressures are needed to synthesize diamond, but this process works just fine at room temperature and without a pressure chamber, and even allows diamond patterns to be written. Such patterns could find use in future computer chips, quantum computers, and biosensors.
Source: Purdue University
Posted: November 6, 2014 06:39AM
Though most people only associate gasoline and other fuels with oil, there are a great many products derived from it, including plastics and pharmaceuticals. The reason oil is used to make these products is because they require large organic molecules, which oil contains, but many groups are searching for replacements. One possibility is lignin, a plant material that has previously been hard to work with, but now researchers at the University of Wisconsin, Madison have found a way to break it down to the desired materials.
Lignin is comprised of rings of six carbon atoms called aromatics, which could be used to create other chemicals. First the chains of rings must be broken, which the lignin resists. However, oxygen can be used to weaken the bonds and then an acid can be applied to break them. What the researchers discovered was that the acid could be used with a metal catalyst, and that more aromatics were produced without the metal than with. This is very important as metal catalysts can be quite expensive. Also, the acid steps can be done at the mild conditions of just 110 ºC and low pressure, further keeping costs down.
This is an important step to a biological replacement to oil, but is not a final step. The final steps will involve actually using the aromatics to produce more complex and useful chemicals, but at least we are already familiar with aromatics.
Source: University of Wisconsin, Madison