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When tilling soil, the blade of the tool cuts through dirt, loosening it in preparation for seeding. The dirt granules are pushed aside in a way that looks random -- but might not be. Now, researchers have found a way to distinguish whether such a process is truly random, or is actually deterministic -- which can lead to deeper understanding and the ability to control the process. They describe the analysis in the journal Chaos.

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The 2016 election year highlighted the growing problem of wealth inequality and finding ways to help the people who are falling behind. This human urge of compassion isn’t new, but the big question that remains to be addressed is why inequality is so difficult to erase. This inspired Adrian Bejan at Duke University, who in 1996 discovered the Constructal Law, to provide an answer.

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Proton therapy is a promising form of radiation treatment used to kill cancerous cells and effectively halt their rapid reproduction, and the fundamental understanding for it is contained in the radiation induced water chemistry that occurs immediately after the interaction. The ensuing processes are therefore a subject of considerable scientific interest. Researchers describe their work exploring this ionization with an experimental setup, with enhanced temporal resolution, in this week’s Applied Physics Letters.

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While the ability to easily control the magnetic properties of small electronic systems is highly desirable for future small electronics and data storage, an effective solution has proven to be extremely elusive. But now, a group of researchers from universities in Chile and Brazil are reporting this week in the Journal of Applied Physics, a simple way to gain control of magnetism that starts by controlling the shape of the systems.

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Polystyrene has a glass transition temperature of about 100 C -- at room temperature it behaves like a solid material. But as its temperature approaches the glass transition temperature, polystyrene’s mechanical properties change drastically. This makes the ability to approximate glass transitions for confined geometries in polymers highly desirable. And now, as researchers report in this week's issue of The Journal of Chemical Physics, they’ve developed a simple formula to do just that.

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In just a few years, researchers have achieved remarkable power conversion efficiency with materials with perovskite crystal structure, comparable with the best photovoltaic materials available. Now, researchers have revealed the physics for how an important component of a perovskite solar cell works -- a finding that could lead to improved solar cells or even newer and better materials. They describe their experiments in this week's issue of the journal Applied Physics Letters.

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Magnetic tunnel junctions (MTJs) have played a central role in spintronic devices, and researchers are working to improve their performance. A prominent achievement that accelerated the technology's practical applications was the realization of giant tunnel magnetoresistance (TMR) ratios by using rock-salt type MgO crystalline barrier. In this week's Applied Physics Letters, researchers have succeeded in applying MgGa2O4 to a tunnel barrier, the core part of an MTJ, as an alternative material to more conventional insulators.

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With fracking, scientists have calculated the expected level of capillary rise with the Lucas-Washburn equation, a mathematical model whose earliest parameters were first devised nearly a century ago. The challenge, however, is that that the equation has not been completely accurate in predicting the actual rise observed in nano-capillary laboratory experiments. Researchers studying this deviation describe their findings this week in the journal Applied Physics Letters.

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Researchers in Jülich, Germany have adapted an instrument used for High Resolution Electron Energy Loss Spectroscopy (HREELS) with new components so that the phonon dispersion of a given material can be measured in a matter of minutes. They describe their device this week in the journal Review of Scientific Instruments.

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Researchers in Italy hope to measure Earth’s rotation using a laser-based gyroscope housed deep underground, with enough experimental precision to reveal measurable effects of Einstein’s general theory of relativity. The ring laser gyroscope technology enabling these Earth-based measurements provide, unlike those made by referencing celestial objects, inertial rotation information, revealing fluctuations in the rotation rate from the grounded reference frame. The group discusses their work in this week’s Review of Scientific Instruments.

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A team of researchers at the University of Barcelona have demonstrated a new bonding technique for surface mounted devices that uses an inkjet printer with ink that incorporates silver nanoparticles. The technique, described this week in the Journal of Applied Physics, was developed in response to the industrial necessity for a fast, reliable and simple manufacturing process, and with an eye to reducing the environmental impact of the standard fabrication processes.

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Researchers in Japan noticed that acetone droplets not mixing with the water, because of their own form of the Leidenfrost effect, more commonly observed in water droplets on solid hot surfaces. They studied the fluid dynamics of this interaction, and of the self-propulsion common to the Leidenfrost effect (which has its own name, Marangoni effect) to learn more about the underlying mechanics. Their surprising results appear this week in the journal Physics of Fluids.

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An international collaboration of computational physicists and chemists have shed new light on how the polymer structure bears on the glass-transition temperature in the forming of glass in atactic polystyrene (PS), a commonly used glass substance. Their work is reported this week in The Journal of Chemical Physics.

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Almost all information that exists in contemporary society is recorded in magnetic media, like hard drive disks. Researchers are studying the motion of vortex domain walls -- local regions of charge that collectively store information via their configuration -- driven by magnetic fields in ferromagnetic nanowires, which are configured in a straight line with an asymmetric Y-like branch. They discuss their work in this week’s Journal of Applied Physics.

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Carbonate, bicarbonate, and carbonic acid emerge when atmospheric carbon dioxide dissolves in the oceans, which is the largest sink for this greenhouse gas. Researchers are interested in better understanding the carbonate system to potentially help facilitate carbon sequestration schemes, to help mitigate climate change. Recently, researchers made breakthrough discoveries about the carbonate species’ behavior at saltwater surfaces, like that of the ocean. They report their findings this week in The Journal of Chemical Physics.

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As transistor dimensions within integrated circuits continue to shrink, smooth metallic lines are required to interconnect these devices. If the surfaces of these tiny metal lines aren’t smooth enough, it substantially reduces their ability to conduct electrical and thermal energy -- decreasing functionality. Engineers report an advance this week in Applied Physics Letters, in modeling results that establish electrical surface treatment of conducting thin films as a physical processing method for reducing surface roughness.

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“The laws of life,” a feature article in the March issue of Physics Today, available at http://physicstoday.scitation.org/journal/pto, is a stimulating exploration of how fundamental and universal principles of physics shape life and its success. In addition, an extraordinary tribute to the life of Mildred "Millie" Dresselhaus -- the renowned MIT physicist celebrated for her discoveries of the physics and chemistry of carbon -- appears on the magazine’s website.

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Despite its omnipresence, water has many physical properties that are still not completely understood by the scientific community. One of the most puzzling relates to the activity of water molecules after they undergo a process called “supercooling.” Now, new findings from Roma Tre University, in Rome, Italy, on the interactions of water molecules under these exotic conditions appear this week in The Journal of Chemical Physics.

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Often grouped in wind farms, horizontal-axis wind turbines (HAWTs) provide significant amounts of energy for local communities, but they can take up a lot of space. If placed too close together, one HAWT can make a neighboring HAWT output much less power. To address this, researchers are looking at vertical-axis wind turbines (VAWTs), which could be either arranged in groups or interspersed within HAWT arrays. They report their work this week in the Journal of Renewable and Sustainable Energy.

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Limitations of the piezoelectric array technologies conventionally used for ultrasonics inspired a group of University College London researchers to explore an alternative mechanism for generating ultrasound via light, also known as the photoacoustic effect. Coupling this with 3-D printing, the group was able to generate sounds fields with specific shapes for potential use in biological cell manipulation and drug delivery. As the group reports in this week’s Applied Physics Letters, their work focuses on using the photoacoustic effect to control ultrasound fields in 3-D.

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Display manufacturers can account for a certain level of relaxation in the glass, referring to the intermolecular rearrangement, if it’s known and reproducible. But fluctuations in this relaxation behavior tend to introduce uncertainty into the manufacturing process, possibly leading to misalignment of pixels within displays. Now, researchers reports on a new modeling technique to quantify and predict glass relaxation fluctuations, important for next-generation displays.

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There are several important gases that are detectable with mid-infrared light, having wavelengths between 3-4 micrometers. Application-grade Vertical-cavity surface-emitting lasers (VCSELs), however, aren’t yet available for this wavelength range, but the increasing need for compact, portable and affordable gas sensors is spurring demand for energy-efficient semiconductor sources of mid-IR light. Addressing this demand, a group of researchers set out to develop a concept to extend the wavelength coverage of VCSELs into this important regime.

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For use in quantum sensing, the bulk nanodiamond crystal surrounding the point defect must be highly perfect. Any deviation from perfection will adversely affect the quantum behavior of the material. Highly perfect nanodiamonds are also quite expensive and difficult to make. A cheaper alternative, say researchers, is to take defect-ridden, low-quality, commercially manufactured diamonds, and then “heal” them. In APL Materials, they describe a method to heal diamond nanocrystals under high-temperature conditions.

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One big challenge targeted drug delivery faces today is efficiently “loading” a drug into a carrier without compromising the carrier’s structural integrity. A promising method is to deform a carrier by squeezing it through a narrow, microscale constriction. This mechanical deformation creates transient pores in the carrier membrane to enhance the membrane’s permeability to macromolecules and promote the efficient uptake of drugs. During the Society of Rheology meeting, being held Feb. 12-16, Joseph Barakat will present his work to develop a model for vesicle squeezing that can be used to predict and optimize drug loading procedures.

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While several circulatory system models are used today in an attempt to better understand blood flow, they still don’t account for the complex rheological behavior of blood. Because blood is a complex suspension of red and white blood cells and platelets suspended within a plasma that contains various proteins, it can exhibit complex flow behavior. Many of the models currently used ignore these complexities and assume a Newtonian behavior or a constant thickness. During a Society of Rheology meeting, being held Feb. 12-16, Jeffrey S. Horner will present a new approach.

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Symptoms of dry eye syndrome -- dry, red, itchy, gritty, sore eyes -- are more common among contact lens wearers. But relief may be on the horizon, thanks to a group of Stanford University researchers and their work exploring the mechanical interactions between the eye surface, the cornea and contact lenses. Ultimately, the group’s goal is to create better contact lenses that maximize comfort and alleviate dry eye symptoms, and their work will be presented at the Society of Rheology meeting being held Feb. 12-16, in Tampa, Florida.

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Hagfish are marine fish shaped like eels, famous for releasing large quantities of “slime” that unfolds, assembles and expands into the surrounding water in response to a threat. Gaurav Chaudhary, at the University of Illinois at Urbana-Champaign, will present his work on hagfish slime during the 88th Annual Meeting of The Society of Rheology, being held Feb. 12-16, in Tampa, Florida. The research explores the hagfish’s slime formation and the special properties allowing it to assemble into a solid gel without dissolving into the surrounding water.

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Researchers in Singapore and China have collaborated to develop a self-powered photodetector that can be used in a wide range of applications such as chemical analysis, communications, astronomical investigations and much more.

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A research team of physicists from Harvard University has developed new hand-held spectrometers capable of the same performance as large, benchtop instruments. The researchers’ innovation, explained this week in APL Photonics, derives from their groundbreaking work in meta-lenses. The hand-held spectrometers offer real promise for applications ranging from health care diagnostics to environmental and food monitoring.

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Many forms of energy surround you: sunlight, the heat in your room and even your own movements. All that energy -- normally wasted -- can potentially help power your portable and wearable gadgets, from biometric sensors to smart watches. Now, researchers from the University of Oulu in Finland have found that a mineral with the perovskite crystal structure has the right properties to extract energy from multiple sources at the same time.

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Superconductivity is one of modern physics’ most intriguing scientific discoveries. However, practical exploitation of superconductivity also presents many challenges. The challenges are perhaps greatest for researchers trying to integrate superconductivity in small, portable systems. Researchers demonstrate this week in Applied Physics Letters, that a portable superconducting magnetic system, which is, in essence, a high performance substitute for a conventional permanent magnet, can attain a 3-tesla level for the magnetic field.

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A light-sensing protein from a salt-loving, sulfur-forming microbe has proved key to developing methods essential to advanced drug discovery, understanding human vision and other biomedical applications. In a review published this week in Structural Dynamics, by AIP Publishing, physicist Marius Schmidt of the University of Wisconsin‐Milwaukee presents a history of decades of research of this microbe and the many new technologies that have enabled these applications.

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Spider silk offers new inspiration for developments in artificial muscle technology thanks to research from a collaboration of scientists in China and the U.S., the results of which are published today in Applied Physics Letters, from AIP Publishing.

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As interest and demand for nanotechnology continues to rise, so will the need for nanoscale printing and spraying, which relies on depositing tiny drops of liquid onto a surface. Now researchers from Tsinghua University in Beijing have developed a new theory that describes how such a nanosized droplet deforms and breaks up when it strikes a surface.

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For years, B. Ubbo Felderhof, RWTH Aachen University, has explored the mechanisms fish and microorganisms rely on to propel themselves. He has created mechanical models to support the theory behind the “swimming” of microorganisms, consisting of linear chains of spheres connected by springs and immersed in fluid, and he’s just pushed this work even further by addressing what happens when adding one sphere to the chain that’s much larger than the others.

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Researchers studying the brain have long been interested in its neural oscillations, the rhythmic electrical activity that plays an important role in the transmission of information within the brain’s neural circuits. Working with the Wilson-Cowan model, a widely-used model in computational neuroscience that describes the average activity of populations of interconnected neurons, Leandro Alonso has designed a new mathematical tool to help explore the broad spectrum of responses possible from a simple neural circuit. Alonso explains his findings this week in the journal Chaos.

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The American Institute of Physics (AIP) and the Acoustical Society of America (ASA) are both accepting submissions for their respective 2017 science writing awards. The deadline for entries for both awards is March 31, 2017.

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Inspired by micro-scale motions of nature, a group of researchers at the Indian Institute of Technology Madras and the Institute of Mathematical Sciences, in Chennai, India, has developed a new design for transporting colloidal particles, tiny cargo suspended in substances such as fluids or gels, more rapidly than is currently possible by diffusion.

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Shrinking the investigation of objects to the nanometer scale often reveals new properties of matter that have no equivalent for their bulk analysis. This phenomenon is motivating studies of nanomaterials which can reveal fascinating new phenomena. It inspired researchers to explore the extent of knowledge about fundamental properties of fluids, which demands reconsideration with the increasing use of fluids in the decreasing sizes of new devices, where their flow is confined into ever-smaller capillary tubes.

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The American Institute of Physics (AIP) and the American Astronomical Society (AAS) announced today, on behalf of the Heineman Foundation for Research, Educational, Charitable, and Scientific Purposes, that California astrophysicist Lars Bildsten is the winner of the 2017 Heineman Prize for Astrophysics, a distinguished honor awarded annually to recognize significant contributions to the field.

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Love it or hate it, you've probably at least heard of CBS’s hit TV show “The Big Bang Theory,” now in its 10th year of production. But how accurately does it portray scientific culture, and does it break or reinforce stereotypes? A free article in this month’s edition of Physics Today and a companion Inside Science video interview with its author explore these questions.

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After demonstrating the first acoustically driven tractor beam platform, researchers develop a simpler, cheaper version using 3-D printable parts and open-source electronic components for the maker community

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A team of researchers in Italy set out to develop a simple, ultrasensitive fluorescence detection system of in-flow microRNAs that uses spectrally encoded microgels. As the team reports in Biomicrofluidics, until now such a multiplexed barcode detection approach has only been performed in time-consuming observation procedures, significantly hindering its possible diagnostic performance.

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Cancer is the second leading cause of death in the U.S., making early, reliable diagnosis and treatment a priority. Miniaturized lab-on-chip approaches are prime candidates for developing viable diagnostic tests and instruments because they are small, need only limited test volumes, and can be cost-effective. Researchers have developed just such an approach capable of processing biomolecular samples from blood. They describe their work in this week’s Biomicrofluidics.

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Resembling the Leidenfrost effect seen in rapidly boiling water droplets, a disk of ice becomes highly mobile due to a levitating layer of water between it and the smooth surface on which it rests and melts. The otherwise random rotation and translation (sliding) of the ice block can be directed by controlling the flow dynamics of the melted ice-turned-water close to the disk surface.

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Water is vital to life on Earth, yet from a scientific point of view, much remains unknown about water and its many solid phases, which display a plethora of unusual properties and so-called anomalies that, while central to water’s chemical and biological importance, are often viewed as controversial. This inspired researchers to pursue a better understanding of water and ice as materials, which has a far-reaching impact on many areas of research.

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A team of researchers in Korea has demonstrated the use of a wobulation technique to enhance the resolution of flow lithography produced nanostructures.

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Exoplanet images, investigations into artificial consciousness, privacy concerns about facial screening assessments by neural-networks, and accelerators in a post-grand unification era of physics are all covered in this month’s special December, 2116 edition of Physics Today, the world's most influential and closely followed magazine devoted to physics and the physical sciences community.

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As panic spreads, an entire shoal (collective) of fish responds to an incoming threat in a matter of seconds, seemingly as a single body, to change course and evade a threatening predator. Within those few seconds, the panic-infused information – more technically known as the startle response – spreads through the collective, warning fish within the group that would otherwise have no way to detect such a threat. The ways in which this information spreads and the role played by position dynamics may help us better plan for emergencies.

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A group of Clarkson University mathematicians and a civil engineer developed a passive and noninvasive approach to “listen” to a collection of relevant signals from bridges and other mechanical structures to diagnose changes or damage.