Scientists give graphene one more quality – magnetism

 

A diagram of the magnetized graphene (Image: Shi Lab, UC Riverside) Graphene is extremely strong for its weight, it's electrically and thermally conductive, and it's chemically stable ... but it isn't magnetic. Now, however, a team from the University of California, Riverside has succeeded in making it so. The resulting magnetized graphene could have a wide range of applications, including use in "spintronic" computer chips. While other groups have previously magnetized graphene, they've done so by doping it with foreign substances, and the presence of these impurities has negatively affected its electronic properties. In this case, though, the graphene was able to remain pure. Led by professor of physics and astronomy Jing Shi, the UC Riverside team laid a sheet of regular graphene down on an atomically smooth layer of magnetic yttrium iron garnet. That material then simply magnetized the graphene as it lay against it. Yttrium iron garnet was used due to the fact that certain other magnetic materials could disrupt the graphene’s electrical transport properties. When the sheet of graphene was removed and subsequently exposed to a magnetic field, it was shown to indeed possess magnetic qualities of its own. "This is the first time that graphene has been made magnetic this way," said Shi. "The magnetic graphene acquires new electronic properties so that new quantum phenomena can arise. These properties can lead to new electronic devices that are more robust and multi-functional." Those devices could include improved spintronic chips, that use the spin of electrons – which can be magnetically manipulated – to store data. A paper on the research was recently published in the journal Physical Review Letters. Source: University of California, Riverside

Infant failure to thrive linked to lysosome dysfunction

 

Stained sections of neonatal intestines from mice without two genes that express lysosomal proteins (A and E) appeared abnormally compared to wild type mice and mice missing just one of the two genes (B-D and F-H). Neonatal intestinal disorders that prevent infants from getting the nutrients they need may be caused by defects in the lysosomal system that occur before weaning, according to a new Northwestern Medicine study. Lysosomes are cellular recycling centers responsible for breaking down all kinds of biological material. The study, published in PLOS Genetics, links lysosomal dysfunction with intestinal disorders for the first time, pointing to a previously unknown target for research and future therapies to help infants unable to absorb milk nutrients and gain weight, a diagnosis called failure to thrive. "This finding highlights the critical role the lysosomal system plays in neonatal digestion," said principal author of the study Jaime García-Añoveros, associate professor in Anesthesiology, Neurology and Physiology at Northwestern University Feinberg School of Medicine. "We suspect that many neonatal intestinal pathologies -- leading causes of infant mortality worldwide -- are not appropriately understood and thus treated. The study suggests looking for lysosomal defects in these pathologies." The investigators found that mouse models lacking certain lysosomal proteins developed an intestinal disorder that caused diarrhea and delayed growth between birth and weaning. For all mammals, including humans, intestinal digestion during this nursing period is very different from adult digestion. "Normally food proteins break down in the stomach, and the resulting amino acids are absorbed in the intestine," García-Añoveros said. "But the stomach is not acidic yet in a nursing baby." Instead, proteins reach the intestine undigested in infants. There, cells lining the small intestine called enterocytes degrade the proteins and absorb the amino acids using special lysosomes with digestive enzymes. In the study, mice that lacked two lysosomal proteins normally expressed by enterocytes experienced failure to thrive symptoms throughout the nursing period. The finding suggests that infants with lysosome disorders may be affected with intestinal disorders. Should further research identify this sort of lysosomal dysfunction in humans, infant formulas with proteins already broken down into amino acids could be a simple therapy, said García-Añoveros. "Right now I don't think physicians are thinking of the lysosomal system as particularly important in the intestines," he said. "But we have shown that they are very prominent in digestion during this period of an infant's life. Story Source: The above story is based on materials provided by Northwestern University. The original article was written by Nora Dunne. Note: Materials may be edited for content and length. Journal Reference: Natalie N. Remis, Teerawat Wiwatpanit, Andrew J. Castiglioni, Emma N. Flores, Jorge A. Cantú, Jaime García-Añoveros. Mucolipin Co-deficiency Causes Accelerated Endolysosomal Vacuolation of Enterocytes and Failure-to-Thrive from Birth to Weaning. PLoS Genetics, 2014; 10 (12): e1004833 DOI: 10.1371/journal.pgen.1004833

New micro-ring resonator creates quantum entanglement on a silicon chip

 

A new micro-ring resonator produces a stream of entangled photons on a microchip (Image: Università degli Studi di Pavia) The quantum entanglement of particles, such as photons, is a prerequisite for the new and future technologies of quantum computing, telecommunications, and cyber security. Real-world applications that take advantage of this technology, however, will not be fully realized until devices that produce such quantum states leave the realms of the laboratory and are made both small and energy efficient enough to be embedded in electronic equipment. In this vein, European scientists have created and installed a tiny "ring-resonator" on a microchip that is claimed to produce copious numbers of entangled photons while using very little power to do so. Entangled photons have been produced on a silicon chip before, but the number of pairs produced was low, and the amount of energy required to achieve this was prohibitively high – especially on a low-powered device such as a silicon chip. This is where the new micro-ring resonator claims its points of difference. Created in a collaborative effort between scientists at the Università degli Studi di Pavia, Italy, the Universities of Glasgow and Strathclyde, Scotland, and the University of Ontario, Canada, the new micro-ring resonator at the heart of this work takes the form of a loop etched onto a silicon wafer substrate. By precisely engineering the properties of this tiny device, the researchers have made it produce light in the form of entangled photons. And, by keeping its size down to the micron level and achieving exceptional power efficiencies, they have also made it an ideal candidate for use as an on-chip component. "The main advantage of our new source is that it is at the same time small, bright, and silicon based," said Daniele Bajoni, a researcher at the Università degli Studi di Pavia. "The diameter of the ring resonator is a mere 20 microns, which is about one-tenth of the width of a human hair. Previous sources were hundreds of times larger than the one we developed." With ordinary entangled photon emitters generally being produced with specialty crystals and unable to be miniaturized to much less than a couple of millimeters or so, the researchers looked at alternatives in their early research. Happening upon an existing optoelectronic component, the micro-ring, the scientists soon realized that these devices – already etched onto silicon chips – could be modified to produce co-mingled photons for quantum entanglement. And with low power requirements, an inbuilt resonator, and able to produce photons with a relatively low-powered laser beam, the micro-ring resonator provided the ideal environment for light particle experimentation. A micro-ring (or optical ring) resonator is a device that essentially uses the same principles as those found in whispering galleries, except that instead of sound, they use light. When light of a wavelength resonant ("in tune") with the loop is input from a laser via a waveguide, its intensity increases as it completes multiple circuits around the device until it is finally emitted as a very bright beam of photons at the output.. After some experimental tinkering and tailoring, the scientists were very pleased to find that the micro-ring device they had decided to use was an admirable choice. When the device was "pumped" with a laser, a high number of the subsequent photons streaming from the resonator showed all the hallmarks of quantum entanglement. "Our device is capable of emitting light with striking quantum mechanical properties never observed in an integrated source," said Bajoni. "The rate at which the entangled photons are generated is unprecedented for a silicon integrated source, and comparable with that available from bulk crystals that must be pumped by very strong lasers." Using an already established technology to produce their device, the scientists are confident that the application of their modifications may well soon see the production of silicon chips with inbuilt micro-resonators embedded in modern electronic equipment. "In the last few years, silicon integrated devices have been developed to filter and route light, mainly for telecommunication applications," observed Bajoni. "Our micro-ring resonators can be readily used alongside these devices, moving us toward the ability to fully harness entanglement on a chip." The research was recently published in the journal Optics Infobase. Source: OSA

Lensless space telescope could be 1,000 times stronger than Hubble

 

Artist's concept of the Aragoscope deployed The Hubble space telescope has given us decades of incredible images, but it's reaching the end of its service life and the question is, what will come after? One possibility is the Aragoscope from the University of Colorado Boulder, which uses a gigantic orbital disk instead of a mirror to produce images 1,000 times sharper than the Hubble's best efforts. The Aragoscope is named after French scientist Francois Arago who first noticed how a disk diffracted light waves. The principle is based on using a large disk as a diffraction lens, which bends light from distant objects around the edge of the disk and focuses it like a conventional refraction lens. The phenomenon isn't very pronounced on the small scale, but if the telescope is extremely large, it not only becomes practical, but also extremely powerful. When deployed the Aragoscope will consist of an opaque disk a half mile in diameter parked in geostationary orbit behind which is an orbiting telescope keeping station some tens to hundreds of miles behind that collects the light at the focal point and rectifies it into a high-resolution image. "The opaque disk of the Aragoscope works in a similar way to a basic lens," says CU-Boulder doctoral student and team member Anthony Harness. "The light diffracted around the edge of the circular disk travels the same path length to the center and comes into focus as an image." He added that, since image resolution increases with telescope diameter, being able to launch such a large, yet lightweight disk would allow astronomers to achieve higher-resolution images than with smaller, traditional space telescopes. The Aragoscope is similar to the starshade being developed for NASA, which uses the same telescope and giant floating disk architecture. But where starshade uses the disk to create artificial stellar eclipses to aid planet hunting, the Aragoscope turns the disk into a gigantic diffraction lens. According to the team, the similarity is no coincidence, since starshade was developed by members of the Aragoscope team. The new orbital telescope was selected last June by NASA as one of 12 proposals for its NASA Innovative Advanced Concept (NIAC) program – each of which received US$100,000 to fund nine-months of research for projects ranging from capturing asteroids to sending submarines to the lakes of Titan. The Aragoscope is now up for being one of six projects that will receive an additional US$500,000 in April. The team sees the Aragoscope as a way to penetrate farther into the universe to observe phenomena like black hole event horizons, or turned on the Earth to pick out objects the size of a rabbit. The next phase of the project involves testing the concept. This will involve laboratory work using a one-meter disk set several meters from a telescope. If this is successful, a more dramatic demonstration will use a disk set on a mountain top while a telescope mounted on a helicopter tries to focus on the star Alpha Centauri. Source: University of Colorado Boulder

Moment Case turns your iPhone 6 into an even better camera

 

The Moment Case is designed to make the iPhone 6 an even better camera with interchangeable lenses and a shutter button Image Gallery (12 images) After launching a pair of photography-improving lenses for smartphones last year, Moment is back on Kickstarter with a new case which aims to turn the iPhone 6 into an even better camera. The Moment Case features a multi-state shutter button enabling more traditional DSLR-like shooting, and a built-in mount which allows users to easily attach the firm's interchangeable lens. The Moment Case is a slim case for the iPhone 6 which has been created to improve the experience when using the smartphone as a camera. Available in all-black or black and white color options, the polycarbonate case weighs 46 g (1.6 oz.) and features a lens mount interface, along with a raised grip which is home to a physical shutter button and camera strap mount. A proprietary lens interface on the Moment Case means it's compatible with the firm's well-regarded Wide and Telephoto smartphone optics and, being built-into the case, it no longer requires users to attach a metal plate to the back of their phone. The mount is said to be strong enough that users can leave lenses mounted between shots, and when used in combination with the free Moment App, the lens attached can be automatically recognized. However, the biggest feature of the Moment Case is probably the inclusion of a dedicated multi-state shutter button, something many iPhone photographers have longed for. This is powered by a coin cell battery and connects to the phone via Bluetooth LE. Said to be quick and responsive, the shutter button allows photographers to shoot in a manner more akin to using a traditional camera. Half-pressing will lock focus, while a full press will take a photo, holding the shutter down will trigger burst mode. The case also includes a reinforced, machined aluminum bar under the raised grip which can be used to connect the majority of camera wrist or neck straps. This means the phone can be carried in the same way as a camera, where it's always ready to be used. While you probably wouldn't want to carry your phone around like this all the time, it's a good option to have if you are in a situation where you'll be taking a lot of photos. The free iOS Moment App completes the case-lens-app Moment system. In addition to recognizing what lens is being used (if any) and offering relevant features, the app also allows more control by combining on-screen touch features with presses of the shutter button. For example, while the shutter button can be used for focus and exposure, sliding a finger on the screen can fine tune the lighting. The Moment Case has already reached its US$100,000 funding target on Kickstarter and should start shipping in June. A pledge of $49 will get you an iPhone 6 Moment Case, while $125 is enough for the case and one Moment lens (Wide or Tele). If you want the case and both lenses, that'll be $199, and a $299 limited edition set with a walnut wood grip is also on offer. While the iPhone 6 is currently the only smartphone to be catered for, Moment says cases for other devices could follow.   Source: Moment, Kickstarter

Exercise: A drug-free approach to lowering high blood pressure

 

Having high blood pressure and not getting enough exercise are closely related. Discover how small changes in your daily routine can make a big difference. By Mayo Clinic Staff Heart-Healthy Living Your risk of high blood pressure (hypertension) increases with age, but getting some exercise can make a big difference. And if your blood pressure is already high, exercise can help you control it. Don't think you've got to run a marathon or join a gym. Instead, start slow and work more physical activity into your daily routine. How exercise can lower your blood pressure How are high blood pressure and exercise connected? Regular physical activity makes your heart stronger. A stronger heart can pump more blood with less effort. If your heart can work less to pump, the force on your arteries decreases, lowering your blood pressure. Becoming more active can lower your systolic blood pressure — the top number in a blood pressure reading — by an average of 4 to 9 millimeters of mercury (mm Hg). That's as good as some blood pressure medications. For some people, getting some exercise is enough to reduce the need for blood pressure medication. If your blood pressure is at a desirable level — less than 120/80 mm Hg — exercise can help keep it from rising as you age. Regular exercise also helps you maintain a healthy weight, another important way to control blood pressure. But to keep your blood pressure low, you need to keep exercising. It takes about one to three months for regular exercise to have an impact on your blood pressure. The benefits last only as long as you continue to exercise. How much exercise do you need? Flexibility and strengthening exercises such as lifting weights are an important part of an overall fitness plan, but it takes aerobic activity to control high blood pressure. And you don't need to spend hours in the gym every day to benefit. Simply adding moderate physical activities to your daily routine will help. Any physical activity that increases your heart and breathing rates is considered aerobic exercise, including: Household chores, such as mowing the lawn, raking leaves or scrubbing the floor Active sports, such as basketball or tennis Climbing stairs Walking Jogging Bicycling Swimming The American Heart Association recommends you get at least 150 minutes of moderate exercise, 75 minutes of vigorous exercise or a combination of both each week. Aim for at least 30 minutes of aerobic activity most days of the week. If you can't set aside that much time at once, remember that shorter bursts of activity count, too. You can break up your workout into three 10-minute sessions of aerobic exercise and get the same benefit as one 30-minute session. Weight training and high blood pressure Weight training can cause a temporary increase in blood pressure during exercise. This increase can be dramatic — depending on how much weight you lift. But, weightlifting can also have long-term benefits to blood pressure that outweigh the risk of a temporary spike for most people. If you have high blood pressure and want to include weight training in your fitness program, remember: Learn and use proper form when lifting to reduce the risk of injury. Don't hold your breath. Holding your breath during exertion can cause dangerous spikes in blood pressure. Instead, breathe easily and continuously during each lift. Lift lighter weights more times. Heavier weights require more strain, which can cause a greater increase in blood pressure. You can challenge your muscles with lighter weights by increasing the number of repetitions you do. Listen to your body. Stop your activity right away if you become severely out of breath or dizzy or if you experience chest pain or pressure. If you'd like to try weight training exercises, make sure you have your doctor's OK.

Weighing Gas with Sound and Microwaves

 

Schematic diagram of a gas-filled pressure vessel. The red-to-blue shading represents the temperature gradient in the gas, with the higher (red) temperatures near the top. The ovals represent a standing sound wave; its frequency is mostly determined by the average temperature of the gas. The wavy line represents a resonant electromagnetic wave; its frequency is mostly determined by the length of the tank. Wavelengths are not to scale. NIST scientists have developed a novel method to rapidly and accurately calibrate gas flow meters, such as those used to measure natural gas flowing in pipelines, by applying a fundamental physical principle: When a sound wave travels through a gas containing temperature gradients, the sound wave’s average speed is determined by the average temperature of the gas. Accurate calibrations of gas flow meters issues are of urgent interest to meter manufacturers and calibration labs, with potential impact throughout the natural gas industry. Conventional calibrations are typically conducted during measured time intervals by flowing a gas stream through the meter being calibrated. The quantity of gas that passes through the meter is determined by collecting the gas in a large tank and measuring its average temperature and pressure, which in turn reveals the amount of gas. However, the process of collecting the gas in large tanks generates temperature gradients (different temperatures in different parts of the tank), which make the average difficult to measure. Those gradients persist for hours or days. Thus a fast reading is inherently inaccurate. To get around that problem, current practice entails calibrating many small meters, one at a time, and then using them in parallel to calibrate a larger meter. This produces a more accurate reading, but is inherently time-consuming, and therefore expensive. NIST’s innovation replaces the difficult problem of accurately measuring the average temperature of a large volume of gas with the easier problem of accurately measuring the average speed-of-sound in the gas. In one recent paper, NIST researchers deduced the internal shape, thermal expansion, and volume of a 300 liter collection tank by measuring which microwave frequencies resonated (formed standing waves) within the evacuated tank. In a second set of experiments, described in a forthcoming paper, they filled the tank with argon gas and measured the frequencies of the acoustic resonances. From the frequencies and the pressure, they deduced the mass of the argon in the tank. Finally, they heated the top of the tank to establish a temperature difference across the gas of 4 % of the average gas temperature. The temperature difference changed the acoustic resonance frequencies and the pressure; however, the mass of the argon, as deduced from the frequencies and the pressure was unchanged within 0.01 %. This result implies that the acoustic resonance technique could be used to measure the collected gas, even in the presence of a temperature gradient, such as those that occur in a much larger tanks located outside the well-controlled environment of a laboratory.

That's using your head: Brain regulates fat metabolism, potentially stopping disease

 

Ways of keeping the heart healthy has widened, with the discovery that the brain can help fight off hardening of the arteries. Atherosclerosis -- hardening and narrowing of the arteries -- can be caused by fat build up that causes plaque deposits, and is one of the main causes of cardiovascular disease. Jessica Yue, a newly recruited researcher in the Department of Physiology in the Faculty of Medicine & Dentistry, has shown a link between how the brain can regulate fat metabolism, potentially stopping the development of this disease risk factor in obesity and diabetes. Her findings, published this month in Nature Communications, outlines how the brain can use the presence of fatty acids, which are building blocks of fat molecules, to trigger the liver to reduce its own lipid production. "We know that when there is dyslipidemia, or an abnormal amount of fat in the bloodstream, it's dangerous for health -- largely because this can lead to obesity, obesity-related disorders such as Type 2 diabetes, and atherosclerosis," says Yue, and that "if you can find ways to lower fats in the bloodstream, it helps to lower these chances of diabetes and cardiovascular disease as a result of this atherosclerosis." Yue trained at the Toronto General Research Institute under Tony Lam, where she was a recipient of fellowships from the Canadian Institutes of Health Research (CIHR) and the Canadian Diabetes Association. With her associates in Toronto and with Peter Light, professor of pharmacology in the Faculty of Medicine & Dentistry, she looked at how the infusion of oleic acid, a naturally occurring monounsaturated fatty acid, in the brain "triggers" a signal from the hypothalamus to the liver to lower its fat secretion, which Yue says is a "triglyceride-rich, very-low-density lipoprotein. Light is the co-author of Yue's paper in Nature Communications and is the director of the Alberta Diabetes Institute (ADI), where Yue is applying for membership. "This fat complex is the kind of lipoprotein that is dangerous when its levels in the blood are elevated because it promotes atherosclerosis," she says. The catch, though, is that this "trigger" doesn't work in obesity, a setting in which blood lipid levels are usually high. "In a model of diet-induced obesity, which then leads to insulin resistance and pre-diabetes, oleic acid no longer provides the fat-lowering trigger to the liver." Yue's findings, though, demonstrate how this faulty signal can be bypassed, unveiling potentially other ways to trigger this same function in obese patients. This study could potentially impact how obesity and diabetes are treated, says Yue, which is the focus of her future research. The next steps, she says, will be to look at how the brain can sense other compounds to regulate not only liver secretion of fats, but also liver glucose production, a significant contributing factor to diabetes. As a member of the Group on Molecular and Cell Biology of Lipids and with the strength of the ADI, she feels enthusiastic and inspired by her new research environment at the University of Alberta. "It's a big field and it's emerging," says Yue about neuroscience research in the areas of metabolic disease. "Whereas the peripheral organs have gained a lot of attention in terms of how they release glucose and lipids, it's exciting to see that within the last decade and a half that the brain now is emerging as an organ that has a lot of control over our health." Story Source: The above story is based on materials provided by University of Alberta Faculty of Medicine & Dentistry. The original article was written by Cait Wills. Note: Materials may be edited for content and length.

How creative are you? Depends where you're from

 

With the "creative class" on the rise, many businesses are trying to capitalize on imagination and innovation. But when it comes to creative juices, some societies have a faster flow than others. That's because, as new research from Concordia University suggests, creativity is tied to culture. The study, recently published in The Journal of Business Research, compared nearly 300 individuals from Taiwan, a collectivist society, and Canada, a more individualistic country. Results show that those from individualist societies generate a greater number of ideas as compared to their collectivist counterparts -- though the cultures were on nearly equal footing when it came to the quality of that creative output. Gad Saad, a professor at Concordia's John Molson School of Business, co-authored the study with Concordia graduate student Louis Ho and Mark Cleveland from the University of Western Ontario. They theorized that where a country falls on the individualism vs. collectivism continuum would affect the creative juices that might be "permitted" to flow from members of a particular culture. "Brainstorming is often used as a proxy for creativity, so we decided to conduct brainstorming tasks using culturally neutral stimuli in Taiwan and in Canada," Saad says. He and his co-authors hypothesized that members of an individualistic society would perform particularly well in a task that promotes out-of-the-box thinking such as coming up with the proverbial million-dollar idea, compared with those from a collectivist ethos, who wouldn't be as willing to engage in that kind of thinking because they would be more reluctant to stand out from the group. The researchers recruited students from two universities in Taipei and Montreal and collected data on five measures that will be familiar to anyone who has had to brainstorm in a group: The number of generated ideas The quality of the ideas, as evaluated by independent judges The number of uttered negative statements within the brainstorming groups, such as "This is a dumb idea that will fail." The valence of the negative statements -- "This is the all-time dumbest idea" has a stronger negative connotation than "This idea is rather banal." The confidence level exhibited by group members when asked to evaluate their performance in comparison to other teams. When it comes to creativity, quality trumps quantity "The study largely supported our hypotheses," Saad says. "We found that the individualists came up with many more ideas. They also uttered more negative statements -- and those statements were more strongly negative. The Canadian group also displayed greater overconfidence than their Taiwanese counterparts." But when it came to the quality of ideas produced, the collectivists scored marginally higher than the individualists. "This is in line with another important cultural trait that some collectivist societies are known to possess -- namely being more reflective as compared to action-oriented, having the reflex to think hard prior to committing to a course of action," Saad says. Studies like this one are instrumental in understanding cultural differences that increasingly arise as the globe's economic centre of gravity shifts towards East Asia. "To maximize the productivity of their international teams, global firms need to understand important cultural differences between Western and Eastern mindsets," Saad says. "Brainstorming, a technique often used to generate novel ideas such as new product innovations, might not be equally effective across cultural settings. Even though individuals from collectivistic societies might be coming up with fewer creative ideas, the quality of those ideas tends to be just as good as or marginally better than those of their individualistic counterparts. Employers need to recognize that."

Jan. 12, 1986 Early Morning Space Shuttle Launch

 

On Jan. 12, 1986, the space shuttle Columbia launched at 6:55 a.m. EST from Kennedy Space Center on the STS-61C mission. It was the first spaceflight for now-NASA Administrator Charles F. Bolden, who was a Pilot on the STS-61C crew along with Mission Commander Robert L. Gibson, Mission Specialists Franklin R. Chang-Diaz, Steven A. Hawley and George D. Nelson and Payload Specialists Robert J. Cenker of RCA and U.S. Rep. (now Senator) Bill Nelson. During the six-day flight, crew members deployed the SATCOM KU satellite and conducted experiments in astrophysics and materials processing. The mission was accomplished in 96 orbits of Earth, ending with a successful night landing at Edwards Air Force Base, California, on Jan. 18, 1986. Image Credit: NASA