. Scientific Frontline

Wednesday, February 22, 2023

SLAC, Stanford researchers make a new type of quantum material with a dramatic distortion pattern

This illustration shows how an electronic tug-of-war between the layers of a new quantum material has warped its atomic lattice into a dramatic herringbone-like pattern. Scientists at SLAC and Stanford who created the material are just starting to explore how this 'huge' distortion affects the material's properties.   
Illustration Credit: Greg Stewart/SLAC National Accelerator Laboratory

Created by an electronic tug-of-war between the material's atomic layers, this ‘beautiful’ herringbone-like pattern could give rise to unique features that scientists are just starting to explore.

Researchers at the Department of Energy’s SLAC National Accelerator Laboratory and Stanford University have created a new type of quantum material whose atomic scaffolding, or lattice, has been dramatically warped into a herringbone pattern.

The resulting distortions are “huge” compared to those achieved in other materials, said Woo Jin Kim, a postdoctoral researcher at the Stanford Institute for Materials and Energy Sciences (SIMES) at SLAC who led the study. 

“This is a very fundamental result, so it’s hard to make predictions about what may or may not come out of it, but the possibilities are exciting,” said SLAC/Stanford Professor and SIMES Director Harold Hwang. 

“Based on theoretical modeling from members of our team, it looks like the new material has intriguing magnetic, orbital and charge order properties that we plan to investigate further,” he said. Those are some of the very properties that scientists think give quantum materials their surprising characteristics. 

The research team described their work in a paper published in Nature today.

WVU physicists give the first law of thermodynamics a makeover

Research findings led by Paul Cassak, WVU professor and associate director of the WVU Center for KINETIC Plasma Physics, have broken new ground on how scientists can understand the first law of thermodynamics and how plasmas in space and laboratories get heated. In this photo, argon plasma glows a bluish color in a Center experiment.
Photo Credit: Brian Persinger / West Virginia University

West Virginia University physicists have made a breakthrough on an age-old limitation of the first law of thermodynamics.

Paul Cassak, professor and associate director of the Center for KINETIC Plasma Physics, and graduate research assistant Hasan Barbhuiya, both in the Department of Physics and Astronomy, are studying how energy gets converted in superheated plasmas in space. Their findings, funded by a grant from the National Science Foundation and published in the Physical Review Letters journal, will revamp scientists’ understanding of how plasmas in space and laboratories get heated up, and may have a wide variety of further applications across physics and other sciences.

The first law of thermodynamics states that energy can neither be created nor destroyed, but it can be converted into different forms.

“Suppose you heat up a balloon,” Cassak said. “The first law of thermodynamics tells you how much the balloon expands and how much hotter the gas inside the balloon gets. The key is that the total amount of energy causing the balloon to expand and the gas to get hotter is the same as the amount of heat you put into the balloon. The first law has been used to describe many things — including how refrigerators and car engines work. It’s one of the pillars of physics.”

Trawlers intermix with whale ‘supergroup’ in Southern Ocean

Fin whales surround the research vessel National Geographic Endurance in January 2022.
Video Credit: Eric Wehrmeister

Trawlers working amidst a whale ‘supergroup’ raise red flag about human-whale conflicts in a changing ocean, Stanford study says

Scientists observed close to 1,000 fin whales foraging near Antarctica, while fishing vessels trawled for krill in their midst. Without action, such encounters are likely to become more common as this endangered species recovers and krill harvesting intensifies in the Southern Ocean.

Once driven nearly to extinction, the second-largest animals of all time have recently been spotted in big numbers in the Southern Ocean, competing directly with industrial trawlers for prey, according to research led by scientists from Stanford University and Lindblad Expeditions.

Published in Ecology, the study focuses on scientists’ sighting of an enormous “supergroup” of fin whales foraging for shrimplike animals called krill northwest of the South Orkney Islands in January 2022, with four commercial fishing vessels trawling among them for the same tiny creatures.

The researchers, led by Matthew Savoca of Stanford and Conor Ryan of Lindblad Expeditions, estimate at least 830 and possibly more than 1,100 fin whales were present. This ranks among the largest groups of baleen whales ever recorded since commercial whaling decimated their populations last century.

New zirconia-based catalyst can make plastics upcycling more sustainable

A representation of the zirconia catalyst. The teal shows the mesoporous silica plates, the red represents the zirconia nanoparticles between the two sheets. The polymer chains enter the pores, contact the zirconia nanoparticles, and are cut into shorter chains.
Illustration Credit: Courtesy of Ames National Laboratory

A new type of catalyst breaks down polyolefin plastics into new, useful products. This project is part of a new strategy to reduce the amount of plastic waste and its impact on our environment, as well as recover value that is lost when plastics are thrown away. The catalyst was developed by a team from the Institute for Cooperative Upcycling of Plastic (iCOUP), a U.S. Department of Energy, Energy Frontier Research Center. The effort was led by Aaron Sadow, the director of iCOUP, scientist at Ames National Laboratory, and professor at Iowa State University; Andreas Heyden, professor at the University of South Carolina; and Wenyu Huang, scientist at Ames Lab and professor at Iowa State. The new catalyst is made only of earth-abundant materials, which they demonstrated can break carbon-carbon (CC) bonds in aliphatic hydrocarbons.

Aliphatic hydrocarbons are organic compounds made up of only hydrogen and carbon. Polyolefin plastics are aliphatic hydrocarbon materials composed of long chains of carbon atoms linked together to form strong materials. These materials are a big part of the plastic waste crisis. Wenyu Huang said, “More than half of produced plastics so far are polyolefin based.”

Simulations show aftermath of black hole collision


New simulations of two black holes colliding near the speed of light reveal the mysterious physics of what one astrophysicist calls "one of the most violent events you can imagine in the universe."

"It's a bit of a crazy thing to blast two black holes head-on very close to the speed of light," said Thomas Helfer, a postdoctoral fellow at Johns Hopkins University who produced the simulations. "The gravitational waves associated with the collision might look anticlimactic, but this is one of the most violent events you can imagine in the universe."

The work, which appears today in Physical Review Letters, is the first detailed look at the aftermath of such a cataclysmic clash, and shows how a remnant black hole would form and send gravitational waves through the cosmos.

Black hole mergers are one of the few events in the universe energetic enough to produce detectable gravitational waves, which carry energy produced by massive cosmic collisions. Like ripples in a pond, these waves flow through the universe distorting space and time. But unlike waves traveling through water, they are extremely tiny, and propagate through "spacetime," the mind-bending concept that combines the three dimensions of space with the idea of time.

Cells take on dual identities with competing factors trapped in the nucleus

Image showing one cellular response to Leptomycin B, with F-actin (pink), vimentin (yellow), and DAPI (cyan), in canine epithelial cells (MDCK I) cultured on soft hydrogels. This study demonstrates diverse epithelial-mesenchymal responses to nuclear export inhibition, including concurrent elevation of epithelial and mesenchymal cellular traits. The image was acquired on a laser-scanning confocal microscope using a 40X objective.
Image Credit: Carly Krull, Department of Biomedical Engineering

Cells migrate to different tissues for a variety of reasons, including organ development, tissue repair and the spread of cancer. Researchers in the McKelvey School of Engineering at Washington University in St. Louis has found unexpected activity in the nucleus of healthy cells that provides new insight into cell mechanics.

Amit Pathak, associate professor of mechanical engineering & materials science, working with Carly Krull, a doctoral student in biomedical engineering, and Haiyi Li, who earned a bachelor’s degree in computer science & engineering in 2022, found that when they gave the cancer drug Leptomycin B to healthy cells, the cells stopped growing, but several competing genes in their nuclei became active.

“All of a sudden, everything is happening in the nucleus,” Pathak said. “The factors that slow down the cells, the factors that make the cells faster, the factors that make the cells cohesive and the factors that generate forces in cells all became active. All of these factors are normally competing with each other, and they all became active together.”

NASA's Chandra Discovers Giant Black Holes on Collision Course

NASA’s Chandra X-ray Observatory helped identify two pairs of dwarf galaxies on track to merge.  Dwarf galaxies, which are at least about 20 times less massive than the Milky Way, likely formed larger galaxies through collisions in the early Universe.  These newly-discovered merging dwarf galaxies can be used as analogs for more distant ones that are too faint to observe.  The dwarf galaxies are on collision courses and are found in the galaxy clusters Abell 133 and Abell 1758S.
Full Size Version
Image Credit: X-ray: NASA/CXC/Univ. of Alabama/M. Micic et al.; Optical: International Gemini Observatory/NOIRLab/NSF/AURA

Astronomers have discovered the first evidence for giant black holes in dwarf galaxies on a collision course. This result from NASA’s Chandra X-ray Observatory has important ramifications for understanding how the first wave of black holes and galaxies grew in the early universe.

Collisions between the pairs of dwarf galaxies identified in a new study have pulled gas towards the giant black holes they each contain, causing the black holes to grow. Eventually the likely collision of the black holes will cause them to merge into much larger black holes. The pairs of galaxies will also merge into one.

Scientists think the universe was awash with small galaxies, known as “dwarf galaxies,” several hundred million years after the big bang. Most merged with others in the crowded, smaller volume of the early universe, setting in motion the building of larger and larger galaxies now seen around the nearby universe.

New research reveals 12 ways aquaculture can benefit the environment

Researchers have identified 12 potential ecological benefits of aquaculture including species recovery, habitat restoration, rehabilitation and protection, and removal of overabundant species.
Photo Credit: John French

Aquaculture, or the farming of aquatic plants and animals, contributes to biodiversity and habitat loss in freshwater and marine ecosystems globally, but when used wisely, it can also be part of the solution, new research shows.

Published today in Conservation Biology, University of Melbourne researchers have identified 12 potential ecological benefits of aquaculture. These include species recovery, habitat restoration, rehabilitation and protection, and removal of overabundant species.

Lead author, University of Melbourne researcher Ms. Kathy Overton, said the potential environmental benefits of aquaculture have gone under the radar for many years.

“Most people around the world live near freshwater or marine ecosystems, and we rely on them as sources of food, tourism, recreation, culture, and livelihood,” Ms. Overton said.

“However, our impacts on freshwater and marine ecosystems are degrading important habitats and causing rapid declines in biodiversity. While the negative impacts of some types of aquacultures are well known, we can also use aquaculture as a tool to slow or stop these negative impacts and help restore ecosystems that have been largely lost over the last century.”

Infants Outperform AI in “Commonsense Psychology”

New Study Shows How Infants Are More Adept at Spotting Motivations that Drive Human Behavior

Infants outperform artificial intelligence in detecting what motivates other people’s actions, finds a new study by a team of psychology and data science researchers. Its results, which highlight fundamental differences between cognition and computation, point to shortcomings in today’s technologies and where improvements are needed for AI to more fully replicate human behavior. 

“Adults and even infants can easily make reliable inferences about what drives other people’s actions,” explains Moira Dillon, an assistant professor in New York University’s Department of Psychology and the senior author of the paper, which appears in the journal Cognition. “Current AI finds these inferences challenging to make.”

“The novel idea of putting infants and AI head-to-head on the same tasks is allowing researchers to better describe infants’ intuitive knowledge about other people and suggest ways of integrating that knowledge into AI,” she adds.

“If AI aims to build flexible, commonsense thinkers like human adults become, then machines should draw upon the same core abilities infants possess in detecting goals and preferences,” says Brenden Lake, an assistant professor in NYU’s Center for Data Science and Department of Psychology and one of the paper’s authors.

UrFU Chemists Found a Non-toxic Way to Obtain Piperine from Black Pepper

A new method of obtaining piperine from black pepper is more environmentally friendly than the traditional one.
Photo Credit: Anas Alhajj

An international research team of chemists from Russia (UrFU), the Republic of Congo, and India came up with an alternative to the traditional method of obtaining piperine from black pepper. The scientists used a natural solvent for extraction, which has no toxic properties because it consists of a composition from organic salts and acids that are well soluble in water. Moreover, the extract obtained using this technology has better antioxidant activity. The results of the study are published in the journal Sustainable Chemistry.

"Piperine is a bioactive substance that is found in black pepper. It has many useful properties. First of all, it causes that particular pungent taste. Piperine is used in food to increase the absorption of micro and macronutrients in the human body. For example, piperine may be added to yogurt and cheese. There are numerous studies about piperine, but the novelty of our work is the development of a new technology for extracting this substance from black pepper using natural, "green" solvents," - says Full Professor Elena Kovaleva from the UrFU Department of Organic Synthesis Technology.

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