. Scientific Frontline

Monday, September 19, 2022

Send in the Drones

The new trailer provides more space for the UAS team to work on perfecting aircrafts for flight.
 Credit: Idaho National Laboratory

Ever since the Wright brothers innovated in the back of their bicycle shop in Dayton, Ohio, aviation has been, at heart, a nuts-and-bolts endeavor. For all the sophisticated equipment Idaho National Laboratory’s Unmanned Aerial Systems team has at its disposal for testing high-tech cameras, radios and sensors, there is still a lot of gearhead ingenuity involved.

Here, a $500,000 high-tech surveillance camera is kept aloft on an aircraft powered by a 1/2-horsepower gasoline engine adapted from a Honda pressure washer. The launching catapult for the plane is basically an oversized potato gun.

The group operates both in Idaho Falls and at the INL Site from a base that includes a 1,000-foot paved runway, a control trailer and a newly built 1,500-square-foot hangar.

‘Workhorses’

The Department of Energy complex has noted INL’s strength in testing unmanned aerial vehicles, or UAVs (better known as drones). Over 20 years, the lab has developed capabilities to test new platforms and evaluate technology not only for DOE but also the Department of Defense and private industry. With 890 square miles of open high-altitude desert, a secure border, and a sophisticated wireless test bed, the INL Site has proven to be a great place for testing unmanned aerial vehicles against real-world conditions like severe weather, temperature swings and day/night operations.

Wildfire Smoke May Have Amplified Arctic Phytoplankton Bloom

Satellite image of plume in eastern Arctic Ocean, Aug. 2014
Source: North Carolina State University

Smoke from a Siberian wildfire may have transported enough nitrogen to parts of the Arctic Ocean to amplify a phytoplankton bloom, according to new research from North Carolina State University and the International Research Laboratory Takuvik (CNRS/Laval University) in Canada. The work sheds light on some potential ecological effects from Northern Hemisphere wildfires, particularly as these fires become larger, longer and more intense.

In the summer of 2014, satellite imagery detected a larger than normal algal bloom in the Laptev Sea, located in the Arctic Ocean approximately 850 kilometers (528 miles) south of the North Pole.

“For a bloom that large to occur, the area would need a substantial influx of new nitrogen supply, as the Arctic Ocean is nitrogen-depleted,” says Douglas Hamilton, assistant professor of marine, earth and atmospheric sciences at NC State and co-first author of a paper describing the work. Hamilton was formerly a research associate at Cornell University, where the research was conducted. “So we needed to figure out where that nitrogen was coming from.”

First, the researchers looked at the “usual suspects” for nitrogen input, such as sea ice melt, river discharge and ocean upwelling, but didn’t find anything that would account for the amount of nitrogen necessary for the bloom to occur.

Deformation fingerprints will help researchers identify and design better metallic materials

Materials science and engineering professors Jean-Charles Stinville and Marie Charpagne captured nanoscale deformation events at the origin of metal failure that can help researchers design new materials for medical, transportation, safety, energy and environmental applications. 
Photo credit: Fred Zwicky

Engineers can now capture and predict the strength of metallic materials subjected to cycling loading, or fatigue strength, in a matter of hours – not the months or years it takes using current methods.

In a new study, researchers from the University of Illinois Urbana-Champaign report that automated high-resolution electron imaging can capture the nanoscale deformation events that lead to metal failure and breakage at the origin of metal failure. The new method helps scientists to rapidly predict the fatigue strength of any alloy, and design new materials for engineering systems subject to repeated loading for medical, transportation, safety, energy and environmental applications.

The findings of the study, led by materials science and engineering professors Jean-Charles Stinville and Marie Charpagne, are published in the journal Science.

Fatigue of metals and alloys – such as the repeated bending of a metal paperclip that leads to its fracture – is the root cause of failure in many engineering systems, Stinville said. Defining the relationship between fatigue strength and the microstructure is challenging because metallic materials display complex structures with features ranging from the nanometer to the centimeter scale.

Astro­physics: Star-child­hood shapes stel­lar evo­lu­tion

Tarantula Nebula: In this famous star-forming region in our neighboring galaxy, the Large Magellanic Cloud, many young stars are still in their molecular clouds, pictured by James Webb Space Telescope.
Hi-Res Zoomable Image
Credits: NASA, ESA, CSA, STScI, Webb ERO Production Team

In classical models of stellar evolution, so far little importance has been attached to the early evolution of stars. Thomas Steindl from the Institute of Astro- and Particle Physics at the University of Innsbruck now shows for the first time that the biography of stars is indeed shaped by their early stage. The study was published in Nature Communications.

From babies to teenagers: stars in their "young years" are a major challenge for science. The process of star formation is particularly complex and difficult to map in theoretical models. One of the few ways to learn more about the formation, structure or age of stars is to observe their oscillations. "Comparable to the exploration of the Earth's interior with the help of seismology, we can also make statements about their internal structure and thus also about the age of stars based on their oscillations" says Konstanze Zwintz. The astronomer is regarded as a pioneer in the young field of asteroseismology and heads the research group "Stellar Evolution and Asteroseismology" at the Institute for Astro- and Particle Physics at the University of Innsbruck. The study of stellar oscillations has evolved significantly in recent years because the possibilities for precise observation through telescopes in space such as TESS, Kepler, and James Webb have improved on many levels. These advances are now also shedding new light on decades-old theories of stellar evolution.

Diabetes: when circadian lipid rhythms go wrong

Circadian clocks in human pancreatic islets control the lipid membrane fluidity. Right, human pancreatic islet cells with compromised clocks bear decreased membrane lipid fluidity, as compared to the islet cells with functional clocks (left)
Resized Image using AI by SFLORG
Credit: 2022. Petrenko et al. (2022) Type 2 diabetes disrupts circadian orchestration of lipid metabolism and membrane fluidity in human pancreatic islets. PLoS Biol 20(8): e3001725.

Like all living beings, human physiological processes are influenced by circadian rhythms. The disruption of our internal clocks due to an increasingly unbalanced lifestyle is directly linked to the explosion in cases of type 2 diabetes. By what mechanism? A team from the University of Geneva (UNIGE) and the University Hospitals of Geneva (HUG), in Switzerland, is lifting part of the veil: this disturbance disrupts the metabolism of lipids in the cells that secrete glucose-regulating hormones. Sphingolipids and phospholipids, lipids located on the cell membrane, seem to be particularly affected. This change in lipid profiles then leads to rigidity of the membrane of these cells. These results, to be read in the journal PLOS Biology, provide further evidence of the importance of circadian rhythms in metabolic disorders.

Lipids have a variety of cellular functions. As one of the main components of cell membranes, they are involved in the signaling pathways through which cells communicate with each other and with their environment. “We have known for some time that the disruption of circadian clocks was closely linked to metabolic diseases, such as type 2 diabetes, where the body is no longer able to regulate blood sugar levels effectively,” explains Charna Dibner, a professor in the Departments of Surgery and of Cellular Physiology and Metabolism, as well as in the Diabetes Centre of the UNIGE Faculty of Medicine and the HUG, who led this research. “It is also established that lipids play a significant role in metabolic disorders. But the impact of circadian rhythms on lipid functions remained unknown.”

New Way to Obtain High-Productivity Proton Conductors Found

Natalya Tarasova works on the creation of new proton conductors.
Photo credit: Ilya Safarov.

Scientists from the Ural Federal University and the Institute of High Temperature Electrochemistry of the Ural Branch of the Russian Academy of Sciences carried out the first demonstration of donor and acceptor doping of perovskite with a barium-lanthanum indite block-layer structure. The fundamental possibility of such a method to significantly improve the conducting properties of the material was shown. The work opens a new way to the creation of solid oxide fuel cell electrolytes. An article describing the research and its results was published in Ceramics International.

One of the goals of global materials science is to obtain the highest possible electrical conductivity of electrolytes for their further use in solid oxide fuel cells. For this purpose, doping is the replacement of part of the atoms in the starting materials by atoms of another chemical element (acceptor doping is replacement by atoms with a lower valence, donor doping is replacement by atoms with a higher valence).

"We used barium-lanthanum iodate as the initial structure and during our studies we substituted some indium atoms for titanium (donor doping) and some lanthanum atoms for calcium (acceptor doping) in it. When acceptor doping, oxygen defects - oxygen vacancies - appeared in the crystal lattice of the initial material. This can ensure the transfer of protons - positively charged hydrogen ions - along the crystal lattice. They get into the structure of layered perovskite from humidified air at 300-500°C. The more oxygen defects and, consequently, the greater the concentration of protons in the perovskite crystal lattice and their mobility, i.e. speed, the higher the values of the electrical conductivity of the material," explains Natalya Tarasova, Professor of the Department of Physical Chemistry and Leading Researcher of the Institute of Hydrogen Energy at UrFU.

Saturday, September 17, 2022

The magneto-optic modulator

Electricity flowing through a metal coil generates electric (purple) and magnetic (faint green) fields. This changes the properties of the substrate, which tunes the resonance ring (red) to different frequencies. The whole setup enables the scientists to convert a continuous beam of light (red on left) into pulses that can carry data through a fiber-optic cable. 
Photo Credit: Brian Long

Many state-of-the-art technologies work at incredibly low temperatures. Superconducting microprocessors and quantum computers promise to revolutionize computation, but scientists need to keep them just above absolute zero (-459.67° Fahrenheit) to protect their delicate states. Still, ultra-cold components have to interface with room temperature systems, providing both a challenge and an opportunity for engineers.

An international team of scientists, led by UC Santa Barbara’s Paolo Pintus, has designed a device to help cryogenic computers talk with their fair-weather counterparts. The mechanism uses a magnetic field to convert data from electrical current to pulses of light. The light can then travel via fiber-optic cables, which can transmit more information than regular electrical cables while minimizing the heat that leaks into the cryogenic system. The team’s results appear in the journal Nature Electronics.

Even the smartest AI models don’t match human visual processing

The study employed novel visual stimuli called “Frankensteins
Source/Credit: York University

Deep convolutional neural networks (DCNNs) don’t see objects the way humans do – using configural shape perception – and that could be dangerous in real-world AI applications, says Professor James Elder, co-author of a York University study.

Published in the Cell Press journal iScience, Deep learning models fail to capture the configural nature of human shape perception is a collaborative study by Elder, who holds the York Research Chair in Human and Computer Vision and is Co-Director of York’s Centre for AI & Society, and Assistant Psychology Professor Nicholas Baker at Loyola College in Chicago, a former VISTA postdoctoral fellow at York.

The study employed novel visual stimuli called “Frankensteins” to explore how the human brain and DCNNs process holistic, configural object properties.

“Frankensteins are simply objects that have been taken apart and put back together the wrong way around,” says Elder. “As a result, they have all the right local features, but in the wrong places.”

The investigators found that while the human visual system is confused by Frankensteins, DCNNs are not – revealing an insensitivity to configural object properties.

In the sea anemone, the way you move matters

Sea anemones, it turns out, also benefit from maintaining an active lifestyle, particularly as they grow from ovoid-shaped swimming larvae to sedentary, tubular polyps. The tissue is visualized using actin-staining.
Credit: Ikmi group/EMBL and ALMF/EMBL

Researchers from EMBL’s Ikmi group employed an interdisciplinary approach to show how sea anemone ‘exercise’ changes their developing size and shape, uncovering an intimate relationship between behavior and body development.

As humans, we know that an active lifestyle gives us some control over our form. When we hit the pavement, track our steps, and head to the gym, we can develop muscle and reduce body fat. Our physical activity helps shape our physical figure. But what if we performed similar aerobics in our earliest forms?

Researchers at EMBL’s Ikmi group turned this question towards the sea anemone to understand how behavior impacts body shape during early development. Sea anemones, it turns out, also benefit from maintaining an active lifestyle, particularly as they grow from egg-shaped swimming larvae to sedentary, tubular polyps. This morphological transformation is a fundamental transition in the life history of many cnidarian species, including the immortal jellyfish and corals, the builders of our planet’s richest and most complex ecosystems.

During development, starlet sea anemone larvae (Nematostella) perform a specific pattern of gymnastic movements. Too much or too little muscle activity or a drastic change in the organization of their muscles can cause the sea anemone to deviate from its normal shape.

The Building Blocks for Exploring New Exotic States of Matter

Using the High Flux Isotope Reactor’s DEMAND instrument, neutron scattering studies identified the crystal & magnetic structure of an intrinsic ferromagnetic topological insulator MnBi8Te13. The last column of inset shows its crystal & magnetic structures
Image credit: Oak Ridge National Laboratory.

Topological insulators act as electrical insulators on the inside but conduct electricity along their surfaces. Researchers study some of these insulators’ exotic behavior using an external magnetic field to force the ion spins within a topological insulator to be parallel to each other. This process is known as breaking time-reversal symmetry. Now, a research team has created an intrinsic ferromagnetic topological insulator. This means the time-reversal symmetry is broken without applying a magnetic field. The team employed a combination of synthesis, characterization tools, and theory to confirm the structure and properties of new magnetic topological materials. In the process, they discovered an exotic axion insulator in MnBi8Te13.

Researchers can use magnetic topological materials to realize exotic forms of matter that are not seen in other types of material. Scientists believe that the phenomena these materials exhibit could help advance quantum technology and increase the energy efficiency of future electronic devices. Researchers believe that a topological insulator that is inherently ferromagnetic, rather than gaining its properties by adding small numbers of magnetic atoms, is ideal for studying novel topological behaviors. This is because no external magnetic field is needed to study the material’s properties. It also means the material’s magnetism is more uniformly distributed. However, scientists have previously faced challenges in creating this kind of material. This new material consists of layers of manganese, bismuth, and tellurium atoms. It could provide opportunities for exploring novel phases of matter and developing new technologies. It also helps researchers study basic scientific questions about quantum materials.

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