That may soon change, thanks to the work of an international team of scientists — including UNLV astrophysicist Bing Zhang — which tracked hundreds of the bursts from five different sources and found clues in FRB polarization patterns that may reveal their origin. The team’s findings were reported in the March 17 issue of the journal Science.

FRBs produce electromagnetic radio waves, which are essentially oscillations of electric and magnetic fields in space and time. The direction of the oscillating electric field is described as the direction of polarization. By analyzing the frequency of polarization in FRBs observed from various sources, scientists revealed similarities in repeating FRBs that point to a complex environment near the source of the bursts.

“This is a major step towards understanding the physical origin of FRBs,” said Zhang, a UNLV distinguished professor of astrophysics who coauthored the paper and contributed to the theoretical interpretation of the phenomena.

To make the connection between the bursts, an international research team, led by Yi Feng and Di Li of the National Astronomical Observatories of the Chinese Academy of Sciences, analyzed the polarization properties of five repeating FRB sources using the massive Five-hundred-meter Aperture Spherical radio Telescope (FAST) and the Robert C. Byrd Green Bank Telescope (GBT). Since FRBs were first discovered in 2007, astronomers worldwide have turned to powerful radio telescopes like FAST and GBT to trace the bursts and to look for clues on where they come from and how they’re produced.

Though still considered mysterious, the source of most FRBs is widely believed to be magnetars, incredibly dense, city-sized neutron stars that possess the strongest magnetic fields in the universe. They typically have nearly 100% polarization. Conversely, in many astrophysical sources that involve hot randomized plasmas, such as the Sun and other stars, the observed emission is unpolarized because the oscillating electric fields have random orientations.

That’s where the cosmic detective work kicks in.

In a study the team originally published last year in Nature, FAST detected 1,652 pulses from the active repeater FRB 121102. Even though the bursts from the source were discovered to be highly polarized with other telescopes using higher frequencies — consistent with magnetars — none of the bursts detected with FAST in its frequency band were polarized, despite FAST being the largest single-dish radio telescope in the world.

“We were very puzzled by the lack of polarization,” said Feng, first author on the newly released Science paper. “Later, when we systematically looked into other repeating FRBs with other telescopes in different frequency bands — particularly those higher than that of FAST, a unified picture emerged.”

According to Zhang, the unified picture is that every repeating FRB source is surrounded by a highly magnetized dense plasma. This plasma produces different rotation of the polarization angle as a function of frequency, and the received radio waves come from multiple paths due to scattering of the waves by the plasma.

When the team accounted for just a single adjustable parameter, Zhang says, the multiple observations revealed a systematic frequency evolution, namely depolarization toward lower frequencies.

“Such a simple explanation, with only one free parameter, could represent a major step toward a physical understanding of the origin of repeating FRBs,” he says.

Di Li, a corresponding author of the study, agrees that the analysis could represent a corner piece in completing the cosmic puzzle of FRBs. “For example, the extremely active FRBs could be a distinct population,” he says. “Alternatively, we’re starting to see the evolutionary trend in FRBs, with more active sources in more complex environments being younger explosions.”

The study, “Frequency-dependent polarization of repeating fast radio bursts — implications for their origin,” appeared March 17 in the journal Science. It includes 25 co-authors from 11 institutions and is part of long-running collaboration among institutions. In addition to UNLV and NAOC, collaborating institutions also include Yunnan University, Princeton University, Western Sidney University, Peking University and Green Bank Observatory, USA.

Dr. Ted Price BS’97, Ashbel Smith Professor of neuroscience in the School of Behavioral and Brain Sciences (BBS) and CAPS director, leads a team that is analyzing the origins of how pain is generated by nociceptors — pain-sensing nerve cells — in human dorsal root ganglia (DRG) neurons. Price is co-corresponding author of a study, featured on the cover of the Feb. 16 issue of Science Translational Medicine, that charts the full range of messenger RNA (mRNA) strands — a grouping called the transcriptome — produced in these cells.

Because mRNA is a single-stranded copy of a gene that can be translated into protein, the findings provide neuroscientists with a much better understanding of which genes are expressed in DRG neurons. The study also reinforces the value of studying human tissue — as opposed to animal cells — in the search for pain treatments.

DRG neurons are specialized nerve cells clustered near the base of the spine. Very little work has been done previously with these cells from humans due to the scarcity of their availability for research.

“We’re one of the few groups in the country with access to human donor DRG tissue acquired specifically for research,” said Stephanie Shiers PhD’19, neuroscience research scientist and a joint first author of the paper.

Shiers’ prior research made the case in broad terms that significant differences exist between the nociceptors in mice and humans. That work explained why proposed pain treatments that succeed in mice fail in humans.

“This paper is the next step, clearly demonstrating the profound scale of those differences,” Price said. “An entire set of nociceptors that many people study in mice just aren’t found in humans. There are subtypes in humans that don’t exist even in nonhuman primates.

“It’s not that we should abandon all existing nonhuman models of pain. But some are really good, while others aren’t, depending on what you want to study. When it comes to this aspect of pain, our work shows which is which.”

To profile all the gene activity in a DRG tissue sample, the research team used an advanced technique called spatial transcriptomics, which has enhanced capabilities compared with single-cell RNA sequencing.

“It’s rare to have access to both the human tissue we used and to the technology,” said Dr. Diana Tavares-Ferreira, also a co-first and co-corresponding author of the study and a CAPS fellow. “Spatial transcriptomics allows us to overcome the large size of these neurons and to see with a degree of certainty where and how a gene is expressed in human nociceptors.

“Our main goal was to fully characterize the whole transcriptome of human DRG neurons because so much of the work that’s been done to find new pain therapeutic targets has been in mice. Our results help clarify why those efforts struggle to produce results.”

By describing the neuron types present in human DRG and detailing their gene expression, the team has a much better picture of what the physiological functions are for each gene, Price said.

“With that knowledge, not only can anybody use our data to seek drug targets that they couldn’t have sought before, but in some cases we also don’t need to use the mice at all now. We can use the human information,” he said.

Price called removing that reliance on animal models “a fundamental change,” because it allows scientists to explore how any cell type might interact with any neuron in the human peripheral nervous system.

“We’re now able to approach developing pain therapeutics in a more specific way and to think about how chronic pain happens in people in a different way,” Price said. “My hope is that our findings can change the way people do research in our field. It’s a road map that we will use, and others are welcome to follow.”

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Materials provided by University of Texas at Dallas. Original written by Stephen Fontenot. Note: Content may be edited for style and length.

Solid water, or ice, is like many other materials in that it can form different solid materials based on variable temperature and pressure conditions, like carbon forming diamond or graphite. However, water is exceptional in this aspect as there are at least 20 solid forms of ice known to us.

A team of scientists working in UNLV’s Nevada Extreme Conditions Lab pioneered a new method for measuring the properties of water under high pressure. The water sample was first squeezed between the tips of two opposite-facing diamonds — freezing into several jumbled ice crystals. The ice was then subjected to a laser-heating technique that temporarily melted it before it quickly re-formed into a powder-like collection of tiny crystals.

By incrementally raising the pressure, and periodically blasting it with the laser beam, the team observed the water ice make the transition from a known cubic phase, Ice-VII, to the newly discovered intermediate, and tetragonal, phase, Ice-VIIt, before settling into another known phase, Ice-X.

Zach Grande, a UNLV Ph.D. student, led the work which also demonstrated that the transition to Ice-X, when water stiffens aggressively, occurs at much lower pressures than previously thought.

While it’s unlikely we’ll find this new phase of ice anywhere on the surface of Earth, it is likely a common ingredient within the mantle of Earth as well as in large moons and water-rich planets outside of our solar system.

The team’s findings were reported in the March 17 issue of the journal Physical Review B.

Takeaways

The research team had been working to understand the behavior of high-pressure water that may be present in the interior of distant planets.

To do so, Grande and UNLV physicist Ashkan Salamat placed a sample of water between the tips of two round-cut diamonds known as diamond anvil cells, a standard feature in the field of high pressure physics. Applying a little bit of force to the diamonds enabled the researchers to recreate pressures as high as those found at the center of the Earth.

By squeezing the water sample between these diamonds, scientists drove the oxygen and hydrogen atoms into a variety of different arrangements, including the newly discovered arrangement, Ice-VIIt.

Not only did the first-of-its-kind laser-heating technique allow scientists to observe a new phase of water ice, but the team also found that the transition to Ice-X occurred at pressures nearly three times lower than previously thought — at 300,000 atmospheres instead of 1 million. This transition has been a highly debated topic in the community for several decades.

“Zach’s work has demonstrated that this transformation to an ionic state occurs at much, much lower pressures than ever thought before,” Salamat said. “It’s the missing piece, and the most precise measurements ever on water at these conditions.”

The work also recalibrates our understanding of the composition of exoplanets, Salamat added. Researchers hypothesize that the Ice-VIIt phase of ice could exist in abundance in the crust and upper mantle of expected water-rich planets outside of our solar system, meaning they could have conditions habitable for life.

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Materials provided by University of Nevada, Las Vegas. Original written by Natalie Bruzda. Note: Content may be edited for style and length.

UC College of Engineering and Applied Science assistant professor Jingjie Wu and his students used a two-step cascade reaction to convert carbon dioxide to carbon monoxide and then into ethylene, a chemical used in everything from food packaging to tires.

The study was published in the journal Nature Catalysis in collaboration with the University of California Berkeley and the Lawrence Berkeley National Laboratory.

UC College of Engineering and Applied Science graduate Tianyu Zhang, one of the study’s lead authors, led a similar study last year that examined ways to convert carbon dioxide into methane that could be used as rocket fuel for Martian exploration.

“The significance of the two-stage conversion is that we can increase the ethylene selectivity and productivity at the same time with the low-cost strategy,” Zhang said. “This process can be applied to various reactions because the electrode structure is general and simple.”

Selectivity means isolating the desired compounds. Productivity is the amount of ethylene the reactor can produce.

“We’re selectively reducing carbon emissions into something considered valuable because of its many downstream applications,” Zhang said.

Applications include a variety of industries from steel and cement plants to the oil and gas industry, he said.

“In the future, we can use this technique to reduce carbon emissions and make a profit from it. So, reducing carbon emissions will not be a costly process anymore,” he said.

Ethylene has been called “the world’s most important chemical.” It’s used in a range of plastics from water bottles to PVC pipe, textiles and rubber found in tires and insulation.

Professor Wu said the chemical they produce is known as “green ethylene,” because it is created from renewable sources.

“Ideally we can remove greenhouse gas from the environment while simultaneously making fuels and chemicals,” Wu said. “Power plants and ethylene plants emit a lot of carbon dioxide. Our goal is to capture the carbon dioxide and convert it to ethylene using electrochemical conversion.”

So far, the process requires more energy than it produces in ethylene. By using tandem electrodes, UC engineers were able to boost productivity and selectivity, both of which are key indicators toward making the process commercially attractive to industry, Wu said.

There are huge environmental advantages to containing and converting greenhouse gases, Wu said.

“It’s being pushed by the government. In the future, we’ll need sustainable development so we’ll need to convert carbon dioxide,” he said.

And Wu said copper isn’t necessarily the best catalyst for this reaction, so industry experts have likely alternatives that could boost productivity and efficiency even more.

“Our system is very general, but you can use preferred catalysts,” Wu said. “But even with commercial copper we were able to more than double the performance. With an even better catalyst, we could solve the economic issue.”

Wu last year applied for patents for their design.

Zhang said the system will take some time to become economical. But already they have made tremendous strides, he said.

“The technology has improved a lot in 10 years. So in the next 10 years, I’m optimistic we’ll see similar advances. This is a game changer,” Zhang said.

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Materials provided by University of Cincinnati. Original written by Michael Miller. Note: Content may be edited for style and length.

With the innovation of new materials and green composites, it is easy to overlook materials like bamboo and other natural fibres, explains UBCO Professor of Mechanical Engineering Dr. Abbas Milani. These fibres are now used in many applications such as clothing, the automotive industry, packaging and construction.

His research team has now found a way not only to strengthen these fibres, but reduce their tendency to degrade over time, making them even more environmentally friendly.

“Bamboo has nearly the same strength as a mild steel while exhibiting more flexibility,” says Dr. Milani, the founding director of the Materials and Manufacturing Research Institute. “With its low weight, cost and abundant availability, bamboo is a material that has great promise but until now had one big drawback.”

Bamboo is one of the world’s most harvested and used natural fibres with more than 30-million tonnes produced annually. However, its natural fibres can absorb water and degrade and weaken over time due to moisture uptake and weathering.

Using a process called plastination to dehydrate the bamboo, the research team then use it as a reinforcement with other fibres and materials. Then they cure it into a new high-performance hybrid biocomposite.

First developed by Gunther von Hagens in 1977, plastination has been extensively used for the long-term preservation of animal, human and fungal remains, and now has found its way to advanced materials applications. Plastination ensures durability of the composite material for both short- and long-term use, says Daanvir Dhir, the report’s co-author and recent UBC Okanagan graduate.

“The plastinated-bamboo composite was mixed with glass and polymer fibres to create a material that is lighter and yet more durable than comparable composites,” says Dhir. “This work is unique as there are no earlier studies investigating the use of such plastinated natural fibres in synthetic fibre reinforced polymer composites.”

Dhir says this new durable hybrid bamboo/woven glass fibre/polypropylene composite, treated with the plastination technique has a promising future.

Supported by industrial partner NetZero Enterprises Inc., the research shows that adding only a small amount of plastinated materials to the bamboo can increase the impact absorption capacity of the composite — without losing its elastic properties. This also lowers the material’s degradation rate.

More work needs to be done on the optimization of this process as Dhir says plastination is currently time-consuming. But he notes the benefit of discovering the right composition of plastinated natural fibres will result in a sizable reduction of non-degradable waste in many industries, with a lower environmental footprint.

Future studies are underway to optimize and investigate the effect of plastinating other natural fibres, such as flax and hemp. The researchers also suggest a life cycle analysis of the materials should be conducted under different applications and compared to non-plastinated samples. This will provide a better picture of the corresponding trade-off between the environmental footprint and mechanical durability effects.

“Biocomposites continue to find new applications under the circular economy paradigm,” adds Dr. Milani. “The innovations in the methods used to develop these composites will ensure benefits well into the future.”

Now, ketamine is getting a closer look.

Researchers from UBC Okanagan and the University of Exeter have identified ketamine as a potentially powerful tool in the fight against mental illness.

In a recent study published in the British Journal of Psychiatry, the research team found ketamine to have significant anti-depressant and anti-suicidal effects. They also found evidence that suggests its benefits don’t stop there.

Led by Psychology Professor Dr. Zach Walsh and doctoral student Joey Rootman — both based in the Irving K. Barber Faculty of Arts and Social Sciences — the research team arrived at this conclusion after analyzing more than 150 worldwide studies on the effects of sub-anesthetic ketamine doses for the treatment of mental illness. The study was co-led by Professor Celia Morgan and doctoral student Merve Mollaahmetoglu from the University of Exeter in the United Kingdom.

“We found strong evidence that indicates ketamine provides rapid and robust anti-depressant and anti-suicidal effects, but the effects were relatively short-lived,” explains Rootman. “However, repeated dosing appeared to have the potential to increase the duration of positive effects.”

Beyond these results, the study provides evidence that suggests ketamine may be helpful in the treatment of other disorders, including eating disorders, problematic substance use, post-traumatic stress and anxiety — though the evidence in these areas is scarce.

“What our research provides is an up-to-date overview and synthesis of where the knowledge on ketamine is at right now,” explains Rootman. “Our results signal that ketamine may indeed have a broader spectrum of potential applications in psychiatric treatment — and that tells us that more investigation is needed.”

This study serves as a foundation for fellow researchers looking to design ketamine-related projects and offers valuable data for clinicians considering using ketamine with their patients.

The results also help to satisfy the public’s appetite for information on innovative and emerging psychiatric treatments, says Dr. Walsh, explaining the review provides a relatively compact document with evidence regarding which ketamine treatments may be helpful for diverse diagnoses.

“As many as one in five Canadians will experience a mental illness this year, and the reality is that existing treatments don’t work for everyone,” he says. “As a result, many Canadians are curious about new approaches to help with these serious conditions.”

Overall, while Dr. Walsh acknowledges research into other treatment areas is just beginning, he finds the preliminary evidence encouraging.

“We need a lot more information on how these interventions could work — for example, administering the drug is only a part of treatment. We need to figure out what amount and type of psychotherapy would best compliment the drug intervention to really maximize potential benefits,” he explains. “With that being said, it is a truly exciting time for ketamine research. If it can deliver the relief that early evidence suggests it can, this could be among the most significant developments in mental health treatment in decades.”

Ames Lab has been a leader in rare-earths research since the middle of the 20^th century. Rare earth elements have a wide range of uses including clean energy technologies, energy storage, and permanent magnets. Discovery of new rare-earth compounds is part of a larger effort by scientists to expand access to these materials.

The present approach is based on machine learning (ML), a form of artificial intelligence (AI), which is driven by computer algorithms that improve through data usage and experience. Researchers used the upgraded Ames Laboratory Rare Earth database (RIC 2.0) and high-throughput density-functional theory (DFT) to build the foundation for their ML model.

High-throughput screening is a computational scheme that allows a researcher to test hundreds of models quickly. DFT is a quantum mechanical method used to investigate thermodynamic and electronic properties of many body systems. Based on this collection of information, the developed ML model uses regression learning to assess phase stability of compounds.

Tyler Del Rose, an Iowa State University graduate student, conducted much of the foundational research needed for the database by writing algorithms to search the web for information to supplement the database and DFT calculations. He also worked on experimental validation of the AI predictions and helped to improve the ML based models by ensuring they are representative of reality.

“Machine learning is really important here because when we are talking about new compositions, ordered materials are all very well known to everyone in the rare earth community,” said Ames Laboratory Scientist Prashant Singh, who led the DFT plus machine learning effort with Guillermo Vazquez and Raymundo Arroyave. “However, when you add disorder to known materials, it’s very different. The number of compositions becomes significantly larger, often thousands or millions, and you cannot investigate all the possible combinations using theory or experiments.”

Singh explained that the material analysis is based on a discrete feedback loop in which the AI/ML model is updated using new DFT database based on real-time structural and phase information obtained from our experiments. This process ensures that information is carried from one step to the next and reduces the chance of making mistakes.

Yaroslav Mudryk, the project supervisor, said that the framework was designed to explore rare earth compounds because of their technological importance, but its application is not limited to rare-earths research. The same approach can be used to train an ML model to predict magnetic properties of compounds, process controls for transformative manufacturing, and optimize mechanical behaviors.

“It’s not really meant to discover a particular compound,” Mudryk said. “It was, how do we design a new approach or a new tool for discovery and prediction of rare earth compounds? And that’s what we did.”

Mudryk emphasized that this work is just the beginning. The team is exploring the full potential of this method, but they are optimistic that there will be a wide range of applications for the framework in the future.

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Materials provided by DOE/Ames Laboratory. Note: Content may be edited for style and length.