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  • richardmitnick 9:20 am on July 4, 2020 Permalink | Reply
    Tags: "Geologists Identify Deep-Earth Structures That May Signal Hidden Metal Lodes", Applied Research & Technology, , , , , , The mining of metals needed to create a vast infrastructure for renewable power generation; storage; transmission and usage., The new study started in 2016 in Australia where much of the world’s lead zinc and copper is mined., The scientists’ map shows such zones looping through all the continents., The study’s authors found that the richest Australian mines lay neatly along the line where thick old lithosphere grades out to 170 kilometers as it approaches the coast.   

    From Columbia University – State of the Planet: “Geologists Identify Deep-Earth Structures That May Signal Hidden Metal Lodes” 

    Columbia U bloc

    From Columbia University – State of the Planet

    June 30, 2020
    Kevin Krajick

    Finding New Giant Copper, Lead, Zinc Deposits Will Fuel Green Infrastructure.

    If the world is to maintain a sustainable economy and fend off the worst effects of climate change, at least one industry will soon have to ramp up dramatically: the mining of metals needed to create a vast infrastructure for renewable power generation, storage, transmission and usage. The problem is, demand for such metals is likely to far outstrip currently both known deposits and the existing technology used to find more ore bodies.

    Now, in a new study, scientists have discovered previously unrecognized structural lines 100 miles or more down in the earth that appear to signal the locations of giant deposits of copper, lead, zinc and other vital metals lying close enough to the surface to be mined, but too far down to be found using current exploration methods. The discovery could greatly narrow down search areas, and reduce the footprint of future mines, the authors say. The study appears this week in the journal Nature Geoscience.

    “We can’t get away from these metals—they’re in everything, and we’re not going to recycle everything that was ever made,” said lead author Mark Hoggard, a postdoctoral researcher at Harvard University and Columbia University’s Lamont-Doherty Earth Observatory. “There’s a real need for alternative sources.”

    A new study shows that giant ore deposits are tightly distributed above where rigid rocks that comprise the nuclei of ancient continents begin to thin, far below the surface (white areas). Redder areas indicate the thinnest rocks beyond the boundary; bluer ones, the thickest. Circles, triangles and squares show known large sediment-hosted deposits of different metals. (Adapted from Hoggard et al., Nature Geoscience, 2020)

    The study found that 85 percent of all known base-metal deposits hosted in sediments—and 100 percent of all “giant” deposits (those holding more than 10 million tons of metal)—lie above deeply buried lines girdling the planet that mark the edges of ancient continents. Specifically, the deposits lie along boundaries where the earth’s lithosphere—the rigid outermost cladding of the planet, comprising the crust and upper mantle—thins out to about 170 kilometers below the surface.

    Up to now, all such deposits have been found pretty much at the surface, and their locations have seemed to be somewhat random. Most discoveries have been made basically by geologists combing the ground and whacking at rocks with hammers. Geophysical exploration methods using gravity and other parameters to find buried ore bodies have entered in recent decades, but the results have been underwhelming. The new study presents geologists with a new, high-tech treasure map telling them where to look.

    Due to the demands of modern technology and the growth of populations and economies, the need for base metals in the next 25 years is projected to outpace all the base metals so far mined in human history. Copper is used in basically all electronics wiring, from cell phones to generators; lead for photovoltaic cells, high-voltage cables, batteries and super capacitors; and zinc for batteries, as well as fertilizers in regions where it is a limiting factor in soils, including much of China and India. Many base-metal mines also yield rarer needed elements, including cobalt, iridium and molybdenum. One recent study suggests that in order to develop a sustainable global economy, between 2015 and 2050 electric passenger vehicles must increase from 1.2 million to 1 billion; battery capacity from 0.5 gigawatt hours to 12,000; and photovoltaic capacity from 223 gigawatts to more than 7,000.

    The new study started in 2016 in Australia, where much of the world’s lead, zinc and copper is mined. The government funded work to see whether mines in the northern part of the continent had anything in common. It built on the fact that in recent years, scientists around the world have been using seismic waves to map the highly variable depth of the lithosphere, which ranges down to 300 kilometers in the nuclei of the most ancient, undisturbed continental masses, and tapers to near zero under the younger rocks of the ocean floors. As continents have shifted, collided and rifted over many eons, their subsurfaces have developed scar-like lithospheric irregularities, many of which have now been mapped.

    The study’s authors found that the richest Australian mines lay neatly along the line where thick, old lithosphere grades out to 170 kilometers as it approaches the coast. They then expanded their investigation to some 2,100 sediment-hosted mines across the world, and found an identical pattern. Some of the 170-kilometer boundaries lie near current coastlines, but many are nestled deep within the continents, having formed at various points in the distant past when the continents had different shapes. Some are up to 2 billion years old.

    The scientists’ map shows such zones looping through all the continents, including areas in western Canada; the coasts of Australia, Greenland and Antarctica; the western, southeastern and Great Lakes regions of the United States; and much of the Amazon, northwest and southern Africa, northern India and central Asia. While some of the identified areas already host enormous mines, others are complete blanks on the mining map.

    The authors believe that the metal deposits formed when thick continental rocks stretched out and sagged to form a depression, like a wad of gum pulled apart. This thinned the lithosphere and allowed seawater to flood in. Over long periods, these watery low spots got filled in with metal-bearing sediments from adjoining, higher-elevation rocks. Salty water then circulated downward until reaching depths where chemical and temperature conditions were just right for metals picked up by the water in deep parts of the basin to precipitate out to form giant deposits, anywhere from 100 meters to 10 kilometers below the then-surface. The key ingredient was the depth of the lithosphere. Where it is thickest, little heat from the hot lower mantle rises to potential near-surface ore-forming zones, and where it is thinnest, a lot of heat gets through. The 170-kilometer boundary seems to be Goldilocks zone for creating just the right temperature conditions, as long as the right chemistry also is present.

    “It really just hits the sweet spot,” said Hoggard. “These deposits contain lots of metal bound up in high-grade ores, so once you find something like this, you only have to dig one hole.” Most current base-metal mines are sprawling, destructive open-pit operations. But in many cases, deposits starting as far down as a kilometer could probably be mined economically, and these would “almost certainly be taken out via much less disruptive shafts,” said Hoggard.

    The study promises to open exploration in so far poorly explored areas, including parts of Australia, central Asia and western Africa. Based on a preliminary report of the new study that the authors presented at an academic conference last year, a few companies appear to have already claimed ground in Australia and North America. But the mining industry is notoriously secretive, so it is not clear yet how widespread such activity might be.

    “This is a truly profound finding and is the first time anyone has suggested that mineral deposits formed in sedimentary basins … at depths of only kilometers in the crust were being controlled by forces at depths of hundreds of kilometers at the base of the lithosphere,” said a report in Mining Journal reviewing the preliminary presentation last year.

    The study’s other authors are Karol Czarnota of Geoscience Australia, who led the initial Australian mapping project; Fred Richards of Harvard University and Imperial College London; David Huston of Geoscience Australia; and A. Lynton Jaques and Sia Ghelichkhan of Australian National University.

    Hoggard has put the study into a global context on his website.

    See the full article here .


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    Stem Education Coalition

    Columbia U Campus

    Columbia University was founded in 1754 as King’s College by royal charter of King George II of England. It is the oldest institution of higher learning in the state of New York and the fifth oldest in the United States.

  • richardmitnick 11:47 am on July 3, 2020 Permalink | Reply
    Tags: "West Virginia researchers use neutrons to study materials for power plant improvements", Applied Research & Technology, ORNL Neutron Sciences Spallation Neutron Source   

    From ORNL Neutron Sciences Spallation Neutron Source: “West Virginia researchers use neutrons to study materials for power plant improvements” 


    From ORNL Neutron Sciences

    July 2, 2020
    Jeremy Rumsey

    Researchers from West Virginia University used VULCAN at the Spallation Neutron Source to study materials called high-entropy oxides to develop industrial and consumer-based applications for improved energy storage and conversion. Photographed in December, 2019. Team members include (left) Wei Li, Yi Wang, Wenyuan Li, Hanchen Tian, and Zhipeng Zeng. (Credit: ORNL/Genevieve Martin)

    Vulcan at ORNL

    Finding new, more efficient ways to produce power is a critical mission for the Department of Energy (DOE), and developing more advanced materials is often the key to achieving success.

    Researchers from West Virginia University (WVU) are using neutron scattering at the DOE’s Oak Ridge National Laboratory (ORNL) to study novel materials called high-entropy oxides, or HEOs. Their goal is to collect insights into how the atoms in the HEOs bind together and whether the materials can be used to develop useful applications to improve power plant operations.

    Efficiency affects overall costs for fuel and plant environmental performance. Currently, they are developing HEOs for several applications including a high-temperature gas sensor that will be used to detect carbon monoxide in the flue gas of a coal-fired power plant to allow operators to monitor the plant’s efficiency. A similar sensor is being tested at the Longview Power plant in Maidsville, WV, near the WVU main campus.

    “HEOs are materials that consist of four or more metal oxides mixed together in a certain ratio or proportion to form a homogeneous structure,” said WVU materials scientist Wei Li, who led the five-person team in conducting the ORNL neutron scattering experiments. “We’re using neutrons to see if the materials mix evenly into a single oxide phase or whether they separate into multiple phases, in which case we would need to adjust the ratios of the material’s elements, as well as the manufacturing conditions, to ensure the materials form homogeneously the way we want them to.”

    Research into HEOs is increasing because of their advanced properties such as high resistance to heat and corrosion, as well as their multifunctionality, or potential for dielectric, electrochemical, and catalytic applications. The idea is the more metal oxides that can be successfully mixed together, the more beneficial properties the material will have.

    Most HEOs are synthesized by heating mixtures of metal oxide powders at high temperatures, then cooling the resulting material into a single solid phase. However, says Li, it’s unclear how uniform single-phase HEOs form from the nonuniform, or inhomogeneous, mixtures of raw materials.

    Fewer footprints, better batteries

    The team is performing a series of neutron scattering experiments to study two types of HEOs. The first material is made of magnesium, cobalt, nickel, copper, and zinc oxides—atomically arranged in a cube-shaped rock-salt structure, like sodium chloride. The second material the team is studying is a perovskite, made from rare-earth and transition metals (plus oxygen).

    To lower the carbon footprint, the team intends to develop the first type of HEO material into a gas sensor that can be mounted high inside a power plant’s exhaust stack, where temperatures range around 1,800°F (about 980°C).

    “The sensors will be placed in hard-to-reach areas with harsh conditions. Achieving a single phase is important for the stability of the material and its sensitivity to detect carbon monoxide that we want to prevent from reaching the atmosphere,” said Li.

    What’s more, the raw form of the material used to make the gas sensor can also be used to make components for advanced lithium batteries, just by adding lithium oxide to the list of the raw ingredients ((MgCoNiCuZn)1- xLixO1-δ).

    Li says the lithium-ion batteries currently employed in certain power plants to store excess energy use graphite-based electrodes, which offer good stability but have limited storage capacity. Li is working to upgrade to more robust lithium batteries, but finding high-capacity electrodes with stability comparable to that of graphite poses a challenge. With that in mind, the team aims to use a high-entropy metal oxide to develop an improved electrode for a lithium-ion battery that offers high lithium conduction properties as well as exceptional stability for long-term charging and discharging cycles.

    Perovskite’s potential

    With the perovskite, the team wants to design a catalyst to be used in the development of a fuel cell that can provide an alternative means of generating large amounts of electricity. The researchers say 1 to 2 megawatt fuel cells could eventually be deployed to power industrial-sized facilities or even small communities.

    “Normally, we burn things to create electricity. That means we need oxygen and fuel—or hydrogen,” said fellow WVU research assistant professor Wenyuan Li. “However, fuel cells generate electricity through an electrochemical process that converts the chemical energy from hydrogen and oxygen into electrons by using a catalyst. That’s why we’re developing the perovskite for efficient hydrogen oxidation and oxygen reduction reactions.”

    The need for neutrons

    Neutrons are an ideal tool for the research team because of the particles’ deep material-penetrating properties and their acute sensitivity to light elements such as lithium. Likewise, the VULCAN diffractometer at SNS is an ideal instrument for studying the three applications the WVU team is investigating. VULCAN has large-area detectors and high penetration capabilities perfect for studying bulky industrial-size samples—such as engine blocks—under an array of simulated operating conditions such as extreme pressures and temperatures.

    Using VULCAN, the researchers were able to track in real time the movement of individual elements or atoms in the materials, gaining insights into how the HEOs form during manufacturing to learn whether they formed single or multiple phases during and after the heating and cooling treatments.

    WVU researchers make adjustments to the furnace used to study high-entropy oxides under a range of temperatures from room temperature to 1,200° (2,192°F), allowing them to better understand how HEOs form during the manufacturing process. Photographed in December, 2019. (Credit: ORNL/Genevieve Martin)

    “VULCAN is a very balanced and powerful tool. Some of the in situ measurements we’re doing take between 12 and 20 hours of heating and cooling, and we’re able to monitor how the structures change every minute to 30 seconds,” said Wenyuan Li. “We were able to analyze a lot of materials in a relatively short time.”

    The WVU researchers were first-time users of neutron scattering. Data gathered will further aid them in fine-tuning the elemental ratios in their materials and making minute adjustments to their manufacturing methods to ensure materials with the highest quality and efficiency in the end.

    SNS is a DOE Office of Science User Facility. UT-Battelle LLC manages ORNL for the DOE Office of Science. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit http://www.energy.gov/science.

    See the full article here .

    Please help promote STEM in your local schools.

    Stem Education Coalition

    ORNL Neutron Sciences

    ORNL Spallation Neutron Source

    The Neutron Sciences Directorate (NScD) seeks to answer big science questions about the fundamental nature of materials at the atomic scale. By answering big science questions, neutrons help spur innovations that improve our daily lives: more powerful computers, more effective drugs, longer lasting batteries, and improved armor for the military.

    NScD achieves its mission by delivering a world-class neutron science program made possible by the safe and reliable operation of two of the most advanced neutron scattering facilities in the world: the High Flux Isotope Reactor (HFIR) and the Spallation Neutron Source (SNS). These two facilities are funded by the US Department of Energy’s Office of Science and Office of Basic Energy Sciences. In partnership with the University of Tennessee, NScD operates the Shull Wollan Center—a Joint Institute for Neutron Sciences to promote excellence in advancing the application of neutrons to the forefront of science and industry, and it is dedicated to the training and education of future researchers.

    ORNL is managed by UT-Battelle for the Department of Energy’s Office of Science. DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time.


  • richardmitnick 10:28 am on July 3, 2020 Permalink | Reply
    Tags: "Towards Lasers Powerful Enough to Investigate a New Kind of Physics", Applied Research & Technology, Institut national de la recherche scientifique INRS Quebec, ,   

    From Institut national de la recherche scientifique INRS Quebec: “Towards Lasers Powerful Enough to Investigate a New Kind of Physics” 


    From Institut national de la recherche scientifique INRS Quebec

    July 2, 2020
    Audrey-Maude Vézina

    In a paper that made the cover of the journal Applied Physics Letters, an international team of researchers has demonstrated an innovative technique for increasing the intensity of lasers. This approach, based on the compression of light pulses, would make it possible to reach a threshold intensity for a new type of physics that has never been explored before: quantum electrodynamics phenomena.


    Since the invention of frequency drift amplification in 1985 by Donna Strickland and Gérard Mourou, laser power has increased phenomenally, to finally reach a limit in the last years. Many research groups are amplifying the energy of the laser to increase its power, but this approach is expensive and requires beams and optics that are very large, more than a metre in size.

    Researchers Jean-Claude Kieffer of the Institut national de la recherche scientifique (INRS), E. A. Khazanov of the Institute of Applied Physics of the Russian Academy of Sciences and Gérard Mourou, Professor Emeritus of the Ecole Polytechnique in France, who was awarded the Nobel Prize in Physics in 2018, have chosen another direction to achieve a power of around 10^23 Watts (W). Rather than increasing the energy of the laser, they decrease the pulse duration to only a few femtoseconds. This would keep the system within a reasonable size and keep operating costs down.

    To generate the shortest possible pulse, the researchers are exploiting the effects of non-linear optics. “A laser beam is sent through an extremely thin and perfectly homogeneous glass plate. The particular behaviour of the wave inside this solid medium broadens the spectrum and allows for a shorter pulse when it is recompressed at the exit of the plate,” explains Jean-Claude Kieffer, co-author of the study published online on 15 June 2020 in the journal Applied Physics Letters.

    Installed in the Advanced Laser Light Source (ALLS) facility at INRS, the researchers limited themselves to an energy of 3 joules for a 10-femtosecond pulse, or 300 terawatts (1012W).

    Advanced Laser Light Source (ALLS) Université du Québec – Institut national de la recherche scientifique (INRS), Varennes, Québec

    They plan to repeat the experiment with an energy of 13 joules over 5 femtoseconds, or an intensity of 3 petawatts (1015 W). “We would be among the first in the world to achieve this level of power with a laser that has such short pulses,” says Professor Kieffer.

    “If we achieve very short pulses, we enter relativistic problem classes. This is an extremely interesting direction that has the potential to take the scientific community to new horizons,” says Professor Kieffer. “It was a very nice piece of work solidifying the paramount potential of this technique,” concludes Gérard Mourou.

    See the full article here.


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  • richardmitnick 2:33 pm on July 2, 2020 Permalink | Reply
    Tags: Applied Research & Technology, , , , , ,   

    From Caltech: “Slow Earthquakes in Cascadia are Predictable” 

    Caltech Logo

    From Caltech

    July 01, 2020

    Robert Perkins
    (626) 395‑1862

    Cascadia subduction zone

    Evidence mounts that slow-slip seismic events follow a deterministic pattern.

    If there is one word you are not supposed to use when discussing serious earthquake science, it is “predict.” Seismologists cannot predict earthquakes; instead they calculate how likely major earthquakes are to occur along a certain fault over a given period of time.

    It is a matter of debate among seismologists whether the process that drives earthquakes—the loading of strain along a fault followed by the sudden, sharp release of energy as two tectonic plates grind against one another—is a stochastic (random) process, for which only an estimate of the probability of occurrence can be made, or whether it is a deterministic, and potentially predictable, process.

    Seismologists at Caltech studied a decade’s worth of so-called “slow-slip events,” which result from episodic fault slip like regular earthquakes but only generate barely perceptible tremors, in the Cascadia region of the Pacific Northwest. Their analysis shows that this particular type of seismic event is deterministic and potentially could be predictable days or even weeks in advance.

    A paper about the work was published in the journal Science Advances on July 1.

    “Deterministic chaotic systems, despite the name, do have some predictability. This study is a proof of concept to show that friction at the natural scale behaves like a chaotic system, and consequently has some degree of predictability,” says Adriano Gualandi, the lead and corresponding author of the paper. Gualandi was a postdoctoral scholar in the lab of Jean-Philippe Avouac, the Earle C. Anthony Professor of Geology and Mechanical and Civil Engineering, while working on this research. Gualandi and Avouac collaborated with Sylvain Michel, who worked on this project as a graduate student at Caltech, and Davide Faranda of Institut Pierre Simon Laplace in France on the study.

    Slow-slip events were first noted about two decades ago by geoscientists tracking otherwise imperceptible shifts in the earth using global positioning system (GPS) technology. The events occur when tectonic plates grind incredibly slowly against each other, like an earthquake in slow motion. A slow-slip event that occurs over the course of weeks might release the same amount of energy as a one-minute-long magnitude 7.0 earthquake. However, because these quakes release energy so slowly, the deformation that they cause at the surface is on the scale of millimeters, despite affecting areas that may span thousands of square kilometers.

    As such, slow-slip events were only discovered when GPS technology was refined to the point that it could track those very minute shifts. Slow-slip events also do not occur along every fault; so far, they have been spotted in just a handful of locations including the Pacific Northwest, Japan, Mexico, and New Zealand.

    Slow-slip events are useful to researchers because they build up and reoccur frequently, making it possible to study how strain loads and releases along a fault. Over a 10-year period, 10 magnitude 7.0 or greater slow-slip earthquakes might occur along a given fault. By contrast, most regular earthquakes of that magnitude only reoccur on the order of hundreds of years. Because of this time lag between regular large earthquakes and the lack of instrumental records from hundreds of years ago, it is impossible to precisely compare past events with recent ones.

    GPS stations reveal activity beneath Cascadia where the oceanic floor slides beneath North America. The plate interface is locked at shallow depths (the shaded area), but we see recurring slow-slip events (in blue) that unzip the plate interface, generating tremors (the black dots).

    Despite their name, slow-slip events offer seismologists a way to press “fast-forward” on the loading/slipping process that drives earthquakes. In a short time frame of around 10 years, seismologists using state-of-the-art GPS equipment can observe the cycle repeat itself several times.

    Slow-slip events represent what is known as a “forced non-linear dynamical system.” The motion of the tectonic plates is the force driving the system, while the friction between the plates, which causes pressure to build up and then eventually be released in a slip event, makes the system non-linear; in a non-linear system, the change in output is not proportional to the change in input. Despite the fact that both the motion and the friction can be modeled using fully deterministic differential equations, the starting conditions of the system—how much strain the fault is already under, for example—have a significant impact on long-term outcomes. Not knowing those exact starting conditions is one of the possible reasons that the overall system is unpredictable in the long run. However, an examination of the fault slip history can reveal how often and for how long similar patterns repeated over time. In this way, the team was able to assess the predictability horizon time of slow-slip events.

    “This result is very encouraging,” Gualandi says. “It shows that we are on the right track and, if we manage to get more precise data, we could attempt some real-time prediction experiments for slow earthquakes.”

    Gualandi likens the potential prediction of a slow-slip event to the current science of forecasting the weather, which also involves predictions about a complex, chaotic process (and similarly falls off in accuracy after a week or so). “We already know that approximately every 12 to 14 months there will be a new slow earthquake, but we do not know exactly when it will happen. What we have shown is that it seems to be possible to determine when the fault will slip some days before it happens, similar to the way weather can be forecast fairly accurately a couple days in advance.”

    One key question is whether the findings for slow-slip quakes can translate to the regular earthquakes that shake cities and endanger lives and property. Last year Michel, Avouac, and Gualandi reported evidence that slow-slip earthquakes are a good analogue for their more destructive cousins.

    “If the analogy that we’re drawing between slow earthquakes and regular earthquakes is correct, then regular earthquakes are predictable,” Avouac says. “But even if regular earthquakes are deterministic, the predictability horizon may be very short, possibly on the order of a few seconds, which may be of limited utility. We don’t know yet.”

    See the full article here .

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

    Caltech campus

  • richardmitnick 10:54 am on July 2, 2020 Permalink | Reply
    Tags: "Smart design of flat ‘reflectarray’ satellite antennas", Applied Research & Technology, , , , , , ESA M-ARGO, , GOMX 5   

    From European Space Agency – United Space in Europe: “Smart design of flat ‘reflectarray’ satellite antennas” 

    ESA Space For Europe Banner

    From European Space Agency – United Space in Europe


    The traditional curved antenna reflector is instantly recognisable on a satellite, but also represents one of the bulkiest elements aboard. As an alternative, new ESA-backed software allows antenna designers to achieve comparable radio frequency performance from flatter, smarter ‘reflectarrays’, which can be manufactured cheaply, just like printed circuits. Two forthcoming ESA missions will demonstrate reflectarray antennas, one in Earth orbit and the other into deep space.

    Flatter antennas fit better onto space missions

    Curved antenna reflectors work like the reflective backing around flashlight bulbs, to shape and direct radio energy as desired. In some cases highly complex curvature is designed to achieve particular tasks – for instance telecommunication satellite reflectors might have curvature to avoid broadcasting to one nation state in favour of focusing signals on another.

    With reflectarrays the radio frequency signal is reflected along surface printed elements above a metallic ground plane in such a way that a three-dimensional field is created, comparable to that created through a standard reflector.

    “By flattening antennas in this way, missions can gain in terms of mass and volume, as well as onboard accommodation,” explains ESA antenna engineer Giovanni Toso. “And the cost is also reduced, because producing a specifically-shaped reflector is an expensive business, involving a specially-created moulding with follow-up precision shaping to be performed.

    Flat-panel reflectarray antenna

    “What we do with reflectarrays is move this complexity from the manufacturing to design phase. While producing these flat or flatter surfaces with metallic elements printed on dielectric slabs is comparatively cheap, designing their layout to produce the desired radio frequency characteristics is really challenging mathematically – which is where this new software comes in.”

    Advanced software for reflectarray design

    Antenna specialist TICRA in Denmark is now marketing dedicated software for designing reflectarrays, building on past ESA R&D projects with the company.

    “Reflectarrays can be built either flat, or with a degree of curvature, this additional degree of freedom offering potentially the best of both worlds,” notes Giovanni.

    Reflectarray surface printed elements

    “TICRA’s software can accommodate both options, as well as screens working not only in reflection but also in transmission mode. And in principle it can be used across a very wide spectral domain, its versatility extending even into optical bands.”

    TICRA Chief Technology Officer Erik Jørgensen adds: “The new software has proven to be the missing link needed by antenna designers to take their advanced antenna concepts from the idea level and turn them into actual new technology developments with superior performance. And the contribution from ESA’s experts have been instrumental for reaching this milestone.”

    First reflectarray flights on the way

    Europe’s first reflectarray will be flown in space in 2022, aboard the GomX-5 nanosatellite, the latest in the series of ESA’s technology demonstrating CubeSats.

    GOMX 5 [GOMSpace]

    Developed through a consortium led by Denmark’s GomSpace, the 12-unit CubeSat will include a triple-panel reflectarray that will unfurl in orbit to become a single large antenna, to communicate with the ground.

    A follow-up reflectarray mission will follow a year or two later depending on launch opportunities, in the shape of ESA’s M-Argo – Miniaturised Asteroid Remote Geophysical Observer – which will cross deep space to survey a near-Earth orbit asteroid. M-Argo will incorporate a triple panel reflectrarray as its high gain antenna, to return copious science data back to Earth.

    ESA M-ARGO spacecraft

    See the full article here .

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 9:04 am on July 2, 2020 Permalink | Reply
    Tags: "The Australian story told beneath the sea", Aboriginal artefacts, , Applied Research & Technology, , , , , , , , , , told beneath the sea"   

    From COSMOS: “The Australian story, told beneath the sea” 

    Cosmos Magazine bloc

    From COSMOS

    2 July 2020
    Natalie Parletta

    Archaeological sites could fill vast historical gaps.

    The survey area in the Dampier Archipelago, Western Australia. Credit: Flinders University.

    Submerged archaeological sites discovered off Australia’s northwest coast offer a new window into the migrations, lives and cultures of Aboriginal people thousands of years ago, when the continental shelf was dry.

    This was a time when around 20 million square kilometres of land was exposed, before the last glacial loosened its grip on the planet and melted ice drowned coastal areas – and large swaths of human history – under the sea.

    In Australia alone, two million square kilometres were flooded, hemming back a third of the continent.

    “You’re talking about a huge, expansive cultural landscape inhabited by Aboriginal people all over the country… which is just a blank, empty map,” says Jonathan Benjamin from Flinders University, lead author of a paper published in the journal PLoS ONE.

    “So if you’re looking for the whole picture on Australia’s ancient past, you’ve got to look under water, there’s just no question.”

    Yet the country’s appreciation for underwater archaeology is only just emerging, after taking off in Europe over the last two decades with a growing number of sites revealed in the Mediterranean, the Baltic and the North Sea.

    This is a first for Australia – and the discovery was a leap of faith.

    “It was a high-risk project,” says Benjamin. “There was no guarantee that we would make a discovery of this nature, and we did.”

    His team, which included colleagues from Flinders, the University of Western Australia and James Cook University, set out to show that ancient Aboriginal sites could be preserved on the seabed, venturing into unexplored territory with divers, boats, aircrafts and remote underwater sensing technologies.

    Aboriginal artefacts discovered off the Pilbara coast in Western Australia represent Australia’s oldest known underwater archaeology. Credit: Flinders University.

    The Deep History of Sea Country project, in partnership with the Murujuga Aboriginal Corporation, revealed two submerged settings in Murujuga Sea Country off the Pilbara coast around the Dampier Archipelago.

    One site, at Flying Foam Passage, was estimated to be at least 8500 years old and bore evidence of human activity associated with a freshwater spring 14 metres deep.

    The other was at Cape Bruguieres, with more than 260 lithic artefacts discovered up to 2.4 metres below sea level, dated to at least 7000 years old using radiocarbon and sea-level change analysis along with predictive modelling.

    The artefacts included various food processing, cutting, grinding and muller tools, such as a combined hammer stone and grindstone, which would have been used to grind seeds.

    “So you start to see the kinds of activities and the ideas that people had in mind,” says Benjamin. “They weren’t just randomly bashing rocks together; they were creating a tool that was for a purpose, whether it be a scalloped edge scraper or a long knife or a core tool that could be used like an axe.”

    One big surprise was the difference between the types of archaeological remains under water and those found on land, which clearly differentiates earlier and later cultures.

    The sites might have belonged to the same people who created the world-renowned Murujuga rock art, a heritage listing currently up for reconsideration.

    It’s hard to tie the two together with scientific evidence, says Benjamin. “But you’d have to imagine that the people who were there who left their stone tools on a dry land that is now submerged were also making rock art in the area because it goes back tens of thousands of years.”

    These things matter to people today, even if they’re 40,000 years old, he adds.

    “It matters in the way we protect sites, it matters in the way we create National Parks, it matters in the way we protect against destruction and development. So the marine environment, why would it be treated any differently?”

    “That should make some waves, if you pardon the pun, but it should change the landscape and the way that heritage practice and development-led archaeology is done in Australia.”

    The preserved remains have vast potential. The sites could offer insights into how Aboriginal people dealt with climate change during the last glacial. Present-day people might have a relationship with the sites from their ancestral heritage. And it could shift the timing of Aboriginal settlement back even further.

    “Much of what we currently understand about Australia’s deep past is based on sites which are further inland,” says Flinders’ Chelsea Wiseman, a co-author.

    “This study indicates the potential for Indigenous archaeology to preserve underwater, and that in some cases the artefacts may remain undisturbed for millennia.”

    Benjamin says it’s an exciting step for Australia “as we integrate maritime and Indigenous archaeology and draw connections between land and sea,” which he hopes will continue “long after you and I are gone”.

    “These new discoveries are a first step toward exploring the last real frontier of Australian archaeology.”

    See the full article here .

    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 9:18 am on July 1, 2020 Permalink | Reply
    Tags: "Investigating the interplay between axions and dark photons in the early universe", Applied Research & Technology, , , , ,   

    From phys.org: “Investigating the interplay between axions and dark photons in the early universe” 

    From phys.org

    July 1, 2020
    Ingrid Fadelli

    Figure illustrating the difference in evolution of the axion with and without the mixing with the dark photon. Credit: Hook, Marques-Tavares & Tsai.

    Axions and dark photons are two of the most promising types of particles for unveiling new physics. The axion scalar field explains the absence of an electric dipole moment for the neutron, while the dark photon resembles regular photons responsible for electromagnetism, but it is massive and much more weakly coupled.

    In the past, many cosmologists investigating dynamics in the early universe proposed theories that focused either on axions or dark photons. Research exploring the interactions between these two types of particles in the early universe, on the other hand, is still scarce.

    With this in mind, researchers at University of Maryland and Johns Hopkins University recently carried out a study aimed at investigating the interplay between axions and dark photons in the early universe. Their paper, published in Physical Review Letters, examines a series of examples in which an axion mixes with a massive dark photon within a background magnetic field.

    “While there is a large body of literature on the cosmological evolution of theories with only one of those two particles, we were interested in understanding how the interplay of both of those particles in the early universe could lead to new features and ended up finding very interesting behavior associated with their mixing,” Gustavo Marques-Tavares, one of the researchers who carried out the study, told Phys.org. “The new effects we observed were drastically different from other more commonly considered types of mixing.”

    First of all, Marques-Tavares and his colleagues set out to develop a physical hypothesis or intuition. To do this, they solved a simplified version of specific equations typically applied to complex analytic problems.

    Once they came up with a physical intuition, they used two mathematical techniques known as WKB approximation and adiabatic approximation to attain a set of possible solutions to the problem they were focusing on. The researchers then compared the approximate solutions they identified with exact numerical solutions and found that the two matched fairly well.

    Overall, they suggest that single derivative mixing between massive bosonic fields could prompt substantial changes in the field dynamics. More specifically, it could delay the onset of classical oscillations, decreasing and perhaps even eliminating the friction resulting from the Hubble expansion, which is the rate at which the universe is expanding. The researchers further described the phenomenon they examined using a number of examples, which highlighted possibilities arising from the interplay between axions and dark photons.

    “In many ways, light scalar and vector fields behave more like classical fields than quantum particles in their cosmological evolution,” Marques-Tavares said. “We found that our method greatly enhances the amplitude of the axion compared to a theory that does not include the mixing with a dark photon. Because the energy density stored in the field grows with its amplitude, this leads to a larger final energy density for the axion, allowing it to explain all of the dark matter in the universe.”

    The recent work by this team of researchers introduces calculations that highlight the effects of single derivative mixing between axions and dark photons, as opposed to the more typical mass mixing or kinetic mixing. The results presented by Marques-Tavares and his colleagues also highlight new directions for future research aimed at better understanding the effects of single-derivative mixing between particles, particularly in the early universe. In their next studies, the researchers plan to study dark photons more closely, as they are easy to observe and have thus become popular dark matter candidates.

    “Dark photons are notoriously tricky to produce in the early universe, and thus, it is challenging for them to explain all of dark matter,” Marques-Tavares said. “The same mechanism that allows us to enhance the number of axions can also be used to increase the number of dark photons, allowing them to become a dark matter candidate. We plan on exploring this new mechanism we proposed applied to dark photons.”

    See the full article here .


    Please help promote STEM in your local schools.

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    About Science X in 100 words
    Science X™ is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004 (Physorg.com), Science X’s readership has grown steadily to include 5 million scientists, researchers, and engineers every month. Science X publishes approximately 200 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Science X community members enjoy access to many personalized features such as social networking, a personal home page set-up, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.
    Mission 12 reasons for reading daily news on Science X Organization Key editors and writersinclude 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

  • richardmitnick 9:01 am on July 1, 2020 Permalink | Reply
    Tags: Applied Research & Technology, ,   

    From University of Western Australia: “Underwater cameras reveal biodiversity hotspot in tropical marine park” 

    U Western Australia bloc
    From University of Western Australia

    1 July 2020
    Professor Jessica Meeuwig
    (UWA School of Biological Sciences)
    0400 024 999

    Simone Hewett (UWA Media and PR Manager)
    08 6488 3229
    0432 637 716


    Researchers from The University of Western Australia have found an area of tropical ocean protected under law is a hotspot for iconic marine life but does not provide enough defence from human activities.

    While the Oceanic Shoals Marine Park was found to host an abundance of marine wildlife, the study, published in Frontiers in Marine Science, found the zoning classifications of the park permitted activities that were not compatible with the conservation of these species.

    The survey of marine life in one of the northernmost Commonwealth Marine Parks examined how species interacted with the area’s unique habitat features, including banks and pinnacles that attracted groups of sharks, turtles and large fish.

    Using a combination of sampling techniques, including underwater videography, the team from UWA’s Marine Futures Lab documented 32 species from 370 hours of video footage.

    These ranged from tiny baitfish to ocean top predators such as killer whales, but also included numerous sharks, manta rays, dolphins, turtles, seabirds and sea snakes.

    The data was then used to understand how animals were distributed within the park, particularly relative to prominent habitat features such as banks and pinnacles.

    The number of large vertebrates increased closer to banks and some communities of fish and sharks found on or around the banks also appeared to differ from those found elsewhere. This confirms that banks are key ecological features of regional importance for marine wildlife.

    All cetaceans sighted were in groups that contained young individuals, suggesting the marine park may be of importance in the early life stages of these species.

    Lead author Dr Phil Bouchet said while the declaration of the Marine Park appeared to be a successful example of proactive ocean management, the vast majority of the park remained open to many human activities, including various forms of recreational and commercial fishing.

    “All the banks that have been mapped to date fall into multiple use zones, raising concerns regarding the adequacy of protection provided by the park zoning,” Dr Bouchet said.

    Co-author Jessica Meeuwig, Director of the Marine Futures Lab at UWA, said the area was clearly a hotspot for marine wildlife yet only 4.6 per cent of the park was fully protected from exploitation, namely fishing, mining and oil and gas operations.

    “While the aim of the study was to document the marine wildlife found in the region, the data shows a large abundance and diversity of animals near these banks and shoals,” Professor Meeuwig said.

    “Fishing activities, such as pelagic longline fishing and purse-seining are allowed in 95 per cent of the park, despite marine wildlife such as dolphins and sharks being particularly vulnerable to these fishing gears.

    “This information provides a crucial baseline for park monitoring and management however, the level of protection falls well short of agreed international targets. Park management should be strengthened to protect this northern jewel.”

    The research was funded by the National Environmental Science Programs Marine Biodiversity Hub.

    See the full article here .


    Please help promote STEM in your local schools.

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    U Western Australia Campus

    The University of Western Australia (UWA) is a research-intensive university in Perth, Australia that was established by an act of the Western Australian Parliament in February 1911, and began teaching students for the first time in 1913. It is the oldest university in the state of Western Australia and is colloquially known as a “sandstone university”. It is also a member of the Group of Eight

  • richardmitnick 8:09 am on July 1, 2020 Permalink | Reply
    Tags: Applied Research & Technology, , ,   

    From MIT News: “Exploring interactions of light and matter” 

    MIT News

    From MIT News

    June 30, 2020
    David L. Chandler

    Juejun Hu pushes the frontiers of optoelectronics for biological imaging, communications, and consumer electronics.

    MIT professor Juejun Hu specializes in optical and photonic devices, whose applications include improving high-speed communications, observing the behavior of molecules, and developing innovations in consumer electronics. Image: Denis Paste

    Growing up in a small town in Fujian province in southern China, Juejun Hu was exposed to engineering from an early age. His father, trained as a mechanical engineer, spent his career working first in that field, then in electrical engineering, and then civil engineering.

    “He gave me early exposure to the field. He brought me books and told me stories of interesting scientists and scientific activities,” Hu recalls. So when it came time to go to college — in China students have to choose their major before enrolling — he picked materials science, figuring that field straddled his interests in science and engineering. He pursued that major at Tsinghua University in Beijing.

    He never regretted that decision. “Indeed, it’s the way to go,” he says. “It was a serendipitous choice.” He continued on to a doctorate in materials science at MIT, and then spent four and a half years as an assistant professor at the University of Delaware before joining the MIT faculty. Last year, Hu earned tenure as an associate professor in MIT’s Department of Materials Science and Engineering.

    In his work at the Institute, he has focused on optical and photonic devices, whose applications include improving high-speed communications, observing the behavior of molecules, designing better medical imaging systems, and developing innovations in consumer electronics such as display screens and sensors.

    “I got fascinated with light,” he says, recalling how he began working in this field. “It has such a direct impact on our lives.”

    Hu is now developing devices to transmit information at very high rates, for data centers or high-performance computers. This includes work on devices called optical diodes or optical isolators, which allow light to pass through only in one direction, and systems for coupling light signals into and out of photonic chips.

    Lately, Hu has been focusing on applying machine-learning methods to improve the performance of optical systems. For example, he has developed an algorithm that improves the sensitivity of a spectrometer, a device for analyzing the chemical composition of materials based on how they emit or absorb different frequencies of light. The new approach made it possible to shrink a device that ordinarily requires bulky and expensive equipment down to the scale of a computer chip, by improving its ability to overcome random noise and provide a clean signal.

    The miniaturized spectrometer makes it possible to analyze the chemical composition of individual molecules with something “small and rugged, to replace devices that are large, delicate, and expensive,” he says.

    Much of his work currently involves the use of metamaterials, which don’t occur in nature and are synthesized usually as a series of ultrathin layers, so thin that they interact with wavelengths of light in novel ways. These could lead to components for biomedical imaging, security surveillance, and sensors on consumer electronics, Hu says. Another project he’s been working on involved developing a kind of optical zoom lens based on metamaterials, which uses no moving parts.

    Hu is also pursuing ways to make photonic and photovoltaic systems that are flexible and stretchable rather than rigid, and to make them lighter and more compact. This could allow for installations in places that would otherwise not be practical. “I’m always looking for new designs to start a new paradigm in optics, [to produce] something that’s smaller, faster, better, and lower cost,” he says.

    Hu says the focus of his research these days is mostly on amorphous materials — whose atoms are randomly arranged as opposed to the orderly lattices of crystal structures — because crystalline materials have been so well-studied and understood. When it comes to amorphous materials, though, “our knowledge is amorphous,” he says. “There are lots of new discoveries in the field.”

    Hu’s wife, Di Chen, whom he met when they were both in China, works in the financial industry. They have twin daughters, Selena and Eos, who are 1 year old, and a son Helius, age 3. Whatever free time he has, Hu says, he likes to spend doing things with his kids.

    Recalling why he was drawn to MIT, he says, “I like this very strong engineering culture.” He especially likes MIT’s strong system of support for bringing new advances out of the lab and into real-world application. “This is what I find really useful.” When new ideas come out of the lab, “I like to see them find real utility,” he adds.

    See the full article here .

    Please help promote STEM in your local schools.

    Stem Education Coalition

    MIT Seal

    The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of the MIT community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

    MIT Campus

  • richardmitnick 2:21 pm on June 30, 2020 Permalink | Reply
    Tags: Applied Research & Technology, , , ,   

    From Imperial College London: “Study reveals how water in deep Earth triggers earthquakes and volcanic activity” 

    From Imperial College London

    The Antilles volcanoes (The Quill on Statia)

    Scientists have for the first time linked the deep Earth’s water cycle to earthquakes and volcanic activity.

    Water, sulphur and carbon dioxide, which are cycled through the deep Earth, play a key role in the evolution of our planet – including in the formation of continents, the emergence of life, the concentration of mineral resources, and the distribution of volcanoes and earthquakes.

    Subduction zones, where tectonic plates meet and one plate sinks beneath another, are a key part of the cycle – with large volumes of water going into and coming out from the Earth, mainly through volcanic eruptions. Yet, just how (and how much) water is transported via subduction, and its effect on natural hazards and the formation of natural resources, has been poorly understood.

    Now, a new paper from a project led by researchers from Bristol, Durham, and Imperial has shown that water in the deep Earth triggers earthquakes and volcanic activity by releasing fluids along fault lines and lowering the melting point of rocks.

    The researchers say this is the first conclusive evidence that directly links the water-in and water-out parts of the cycle with magma (melted rock) production and earthquake activity.

    The paper is published in Nature.

    Plate pilgrimage

    As tectonic plates journey from where they are first made at mid-ocean ridges to subduction zones – where they meet other plates – seawater enters the rocks through cracks, faults and by binding to minerals. Upon reaching a subduction zone, the sinking plate heats up and gets squeezed, resulting in the gradual release of some or all of its water.

    The tectonic plates of the world were mapped in 1996, USGS.

    As water is released, it lowers the melting point of the surrounding rocks and generates magma. This magma is buoyant and moves upwards, ultimately leading to eruptions in the overlying chain of volcanic islands, called a volcanic arc.

    A seismometer is deployed from the research vessel

    Lead author Dr George Cooper, of the University of Bristol, said: “These eruptions are potentially explosive because of the volatiles (water, carbon dioxide, and sulphur) contained in the melt. The same process can trigger earthquakes and may affect key properties such as their magnitude and whether they trigger tsunamis or not.”

    While most studies look at the Pacific Ring of Fire, the subducting plates that surround the Pacific Ocean, this research focused on the Atlantic plate, in particular on the Lesser Antilles volcanic arc at the eastern edge of the Caribbean Sea.

    Study co-author Professor Jenny Collier, of Imperial’s Department of Earth Science and Engineering, said: “The Lesser Antilles volcanic arc is one of only two zones where we can see these slow-moving plates. We expect this one to be hydrated more pervasively than the fast spreading Pacific plate, and for expressions of water release, like earthquakes and tsunamis, to be more pronounced.”

    To conduct the study, the research team, known as the Volatile Recycling in the Lesser Antilles (VoiLA) project, collected data over two marine scientific cruises. They deployed seismic stations that recorded earthquakes beneath the seafloor and the islands and undertook geological fieldwork, chemical and mineral analyses of rock samples, and numerical modelling.

    To trace the influence of water along the length of the subduction zone, the scientists studied compositions of the element boron and isotopes of melt inclusions (tiny pockets of trapped magma within volcanic crystals). Boron fingerprints revealed that the water-rich mineral serpentine, contained in the sinking plate, is a dominant supplier of water to the central region of the Lesser Antilles arc.

    The researchers say that by studying these microscopic measurements it is possible to better understand large-scale processes. The combined geochemical and geophysical data provide the clearest indication to date that the structure and amount of water of the sinking plate are directly connected to the volcanic evolution of the arc and its associated hazards.

    Co-author Professor Saskia Goes, also of Imperial’s Department of Earth Science and Engineering, said: “The wettest parts of the plate are where there are major cracks (or fracture zones). By making a numerical model of the history of fracture zone subduction below the islands, we found a direct link to the locations of the highest rates of small earthquakes and the presence of fluids in the subsurface.”

    Installation of seismic stations on the island with University of the West Indies collaborators.

    The history of subduction of water-rich fracture zones can also explain why the central islands of the arc are the largest and why, over geologic history, they have produced the most magma.

    Dr Cooper said: “Our study provides conclusive evidence that directly links the water-in and water-out parts of the cycle and its expressions in terms of magmatic productivity and earthquake activity. This may encourage studies at other subduction zones to find such water-bearing fault structures on the subducting plate to help understand patterns in volcanic and earthquake hazards.”

    Next, the researchers will look into how this pattern of water release may affect the potential for larger earthquakes and possible tsunamis.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Imperial College London is a science-based university with an international reputation for excellence in teaching and research. Consistently rated amongst the world’s best universities, Imperial is committed to developing the next generation of researchers, scientists and academics through collaboration across disciplines. Located in the heart of London, Imperial is a multidisciplinary space for education, research, translation and commercialisation, harnessing science and innovation to tackle global challenges.

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