sciencedaily

Hot tubs and saunas can both soothe aching muscles and provide welcome warmth, but hot tubs might offer greater health benefits.

That's the takeaway from a new study done by researchers in the Bowerman Sports Science Center at the University of Oregon, which compared the physiological effects of soaking in a hot tub to sitting in a traditional dry heat sauna or a more modern far-infrared sauna.

By raising core body temperatures, soaking in hot water can help lower blood pressure, stimulate the immune system and, over time, improve the body's response to heat stress. Moreover, those effects can last beyond the minutes spent directly in heat treatment.

"We compared the most commonly utilized modalities of passive heating as they're used in everyday life and studied in scientific research," said study lead author Jessica Atencio, a doctoral student in the lab of Christopher Minson. "No studies have compared the acute responses between the three."

The results were published in June in theAmerican Journal of Physiology.

Under the guidance of Minson, the Kenneth M. and Kenda H. Singer Endowed Professor of Human Physiology and director of the Bowerman Center, researchers monitored body temperature, blood pressure, heart rate, cardiac output (the amount of blood the heart pumps per minute) and immune cell populations and blood biomarkers of inflammation. Data were collected before, during and after subjects soaked in a hot tub and sat in traditional dry heat and far-infrared saunas.

The study looked at 10 men and 10 women who exercised regularly and ranged in age from 20 to 28 years old. The goal was to isolate the physiological responses to each heating method in a young, healthy population.

"We saw that hot water immersion was the most impactful in increasing core body temperature, which is the main stimulus for these subsequent responses," Atencio said. "Increasing body temperature causes an increase in blood flow, and just the force of blood moving across your vessels is beneficial for your vascular health."

While the research team took blood samples from subjects after each kind of heat therapy, only hot-water immersion produced an inflammatory response as measured by the levels of inflammatory cytokines, a kind of immune signaling molecule, and immune cell populations.

Atencio and her team were not surprised by those results.

"Hot water immersion gives you the most robust changes in core temperature because you can't effectively dissipate heat as you can if you have contact with the air and you're sweating to cool the body," she said. "When you're submerged in water, the sweat mechanisms aren't efficient."

Minson has studied heat therapies for more than two decades. He has focused on how heat interacts with factors such as age, exercise and illness in men and women.

"There's no doubt in my mind that if people are willing to do some heat therapy, it's going to align with improved health, as long as it's done in moderation," Minson said. "If you repeat these stresses over time, our lab and many others have shown that they are consistent with improved health."

Regular exercise can provide benefits similar to and even better in some respects than those from heat therapy, he added, but individuals who are unable or unwilling to exercise may find that heat therapy provides an attractive option.

"It can be a very peaceful, sometimes religious, sometimes cultural and sometimes social experience," Minson said. "And I think those aspects contribute to the health benefits and are critically important."

"We want people to be smart and safe about it," he added. "We need to make sure that they are cleared by their physicians or others for heat therapy or for exercise, whether it's mild to moderate walking or jogging or strength training. Then they'll be fine to do heat therapy."

As a runner herself, Atencio knows people who like to combine heat therapy with exercise.

"We always say that exercise is the primary nonpharmacological treatment that people should be doing to promote health, but some people can't or just won't exercise," she said. "Heat therapy is good supplementation."

Materials provided byUniversity of Oregon.Note: Content may be edited for style and length.

In general, evolution is a long, slow process of tiny changes passed down over generations, resulting in new adaptations and even new species over thousands or millions of years. But when living things are faced with dramatic shifts in the world around them, they sometimes rapidly adapt to better survive. Scientists recently found an example of evolution in real time, tucked away in the collection drawers of the Field Museum in Chicago. By comparing the skulls of chipmunks and voles from the Chicagoland area collected over the past 125 years, the researchers found evidence that these rodents have been adapting to life in an increasingly urban environment.

"Museum collections allow you to time travel," says Stephanie Smith, a mammalogist, XCT laboratory manager at the Field Museum, and co-author of a new paper in the journalIntegrative and Comparative Biologydetailing the discovery. "Instead of being limited to studying specimens collected over the course of one project, or one person's lifetime, natural history collections allow you to look at things over a more evolutionarily relevant time scale."

The Field Museum's mammal collections are made up of more than 245,000 specimens from all over the world, but there's especially good representation of animals from Chicago, where the museum is located. What's more, these collections represent different moments in time throughout the past century.

"We've got things that are over 100 years old, and they're in just as good of shape as things that were collected literally this year," says Smith. "We thought, this is a great resource to exploit."

The researchers picked two rodents commonly found in Chicago: eastern chipmunks and eastern meadow voles. "We chose these two species because they have different biology, and we thought they might be responding differently to the stresses of urbanization," says Anderson Feijó, assistant curator of mammals at the Field Museum and co-author of the study. Chipmunks are in the same family as squirrels, and spend most of their time aboveground, where they eat a wide variety of foods, including nuts, seeds, fruits, insects, and even frogs. Voles are more closely related to hamsters. They mostly eat plants, and they spend a lot of time in underground burrows.

Two of the study's co-authors, Field Museum Women in Science interns Alyssa Stringer and Luna Bian, measured the skulls of 132 chipmunks and 193 voles. The team focused on skulls because skulls contain information about the animals' sensory systems and diet, and they tend to be correlated with overall body size. "From the skulls, we can tell a little bit about how animals are changing in a lot of different, evolutionary relevant ways — how they're dealing with their environment and how they're taking in information," says Smith.

Stringer and Bian took measurements of different parts of the skulls, noting things like the overall skull length and the length of the rows of teeth. They also created 3D scans of the skulls of 82 of the chipmunks and 54 of the voles. This part of the analysis, called geometric morphometrics, entailed digitally stacking the skull scans on top of each other and comparing the distances between different points on them.

These analyses revealed small but significant changes in the rodents' skulls over the past century. The chipmunks' skulls became larger over time, but the row of teeth along the sides of their mouths became shorter. Bony bumps in the voles' skulls that house the inner ear shrank over time. But it wasn't clearwhythey were changing.

To find an explanation for these changes, the scientists turned to historical records of temperature and levels of urbanization. "We tried very hard to come up with a way to quantify the spread of urbanization," says Feijó. "We took advantage of satellite images showing the amount of area covered by buildings, dating back to 1940." (Specimens older than 1940 were either from areas that were still wild in 1940, and thus could safely be assumed to be wild before that, or from highly urbanized areas like downtown Chicago.)

The researchers found that the changes in climate didn't explain the changes in the rodents' skulls, but the degree of urbanization did. The different ways the animals' skulls changed may be related to the different ways that an increasingly urban habitat affected them.

"Over the last century, chipmunks in Chicago have been getting bigger, but their teeth are getting smaller," says Feijó. "We believe this is probably associated with the kind of food they're eating. They're probably eating more human-related food, which makes them bigger, but not necessarily healthier. Meanwhile, their teeth are smaller — we think it's because they're eating less hard food, like the nuts and seeds they would normally eat."

Voles, on the other hand, had smaller auditory bullae, bone structures associated with hearing. "We think this may relate to the city being loud — having these bones be smaller might help dampen excess environmental noise," says Smith.

While these rodents have been able to evolve little changes to make it easier to live among humans, the take-home lesson isn't that animals will just adapt to whatever we throw at them. Rather, these voles with smaller ear bones and chipmunks with smaller teeth are proof of how profoundly humans affect our environment and our capacity to make the world harder for our fellow animals to live in. This is a wake-up call.

"These findings clearly show that interfering with the environment has a detectable effect on wildlife," says Feijó.

"Change is probably happening under your nose, and you don't see it happening unless you use resources like museum collections," says Smith.

Materials provided byField Museum.Note: Content may be edited for style and length.

Climate change and habitat loss are affecting animal populations around the world and reptiles such as South Australia's own endangered pygmy bluetongue are susceptible to higher temperatures and declining long-term rainfall trends.

Flinders University scientists are working on securing a sustainable future for the burrow-dwelling endemic skink (Tiliqua adelaidensis) by assessing their suitability to cooler and slightly greener locations, below their usual range in the state's drier, hotter northern regions.

While the lizards take time to acclimatize to their new homes, translocation remains one of the more important ways to conserve rare species and mitigate extinction risk to climate and habitat changes.

The latest research, outlined in a new article inBiology,compared the ability of three separate pygmy bluetongue lizard populations to withstand different microclimates in South Australia – between the northern Flinders Ranges near Jamestown, Mid North near Burra, and southern-most translocation sites near Tarlee and Kapunda.

The study, led by PhD candidate Deanne Trewartha from the College of Science and Engineering, says moving wildlife adapted to a hotter, drier location to another microclimate can mean exposure to different temperatures, water availability and humidity and needs extensive assessment.

"We need to understand how this species, which are highly dependent on body temperature, adapt to cooler and often wetter seasons in these new environments," says Ms Trewartha, from the Flinders University Lab of Evolutionary Genetics and Sociality (LEGS) research group.

Reptiles rely on attaining certain body temperatures for basic bodily function and increasing body temperature raises dehydration risk.

She says the research so far suggests acclimatization to new sites may take longer than two years for all three populations and may vary with latitude of origin.

"Despite this acclimatization delay, our results indicate that these lizards may cope with translocation as a mitigation strategy in the longer term.

"Further monitoring of the three lineages will continue to see any behavioral variations in wet versus dry seasons and the long-term behavioral acclimatization periods for translocations."

Australia has the highest reptile diversity in the world, and Flinders University Professor of Biodiversity and Ecology Mike Gardner says translocation may be the only way for the conservation of numerous small burrow-dwelling reptiles, other ectotherms and reptile species in future.

"With high biodiversity loss, translocation to 'future-suitable' sites is becoming increasingly urgent for the conservation of numerous reptile species," says Professor Gardner, who leads an Australian Research Council Linkage project to study various pygmy bluetongue groups at different latitudes in South Australia.

"So far, these three populations are showing various responses to their new locations, but behavioral variations may not be detrimental in the long term and may potentially aid animals in acclimatizing to changed environments to optimize their chance their survival."

A previous study published last year noted differences between the way the colonies behaved.

From spring 2020 to autumn 2021, monthly monitoring of behaviors found the translocated southern lineage lizards showed significantly less daily activity and were active at lower temperatures and higher humidity than northern lineage lizards.

Southern lineage lizards allowed a human observer to approach closer as base-of-burrow humidity increased, while northern lineage lizards were quicker to retreat into burrows, at both source and translocation sites.

This project was carried out in accordance with Flinders University ethics approval E453-17, Department of Environment and Water 'Take from the wild' permit 20210331 and research permit G25011. Acknowledgements:The authors acknowledge the Ngadjuri people, who are the traditional custodians of the Mid North study sites and represent the oldest human culture. We acknowledge their elders, past, present and emerging, and that sovereignty was never ceded. Thanks to the Nature Foundation, relevant private landowners, Department for Environment and Water, Renewable Energy Systems Pty Ltd, Flow Power, Nature Foundation and Adelaide Airport Limited for their support in accommodating this research.

Materials provided byFlinders University.Note: Content may be edited for style and length.

Compared with a Mediterranean diet, dietary acid load decreased significantly on a low-fat vegan diet and was associated with weight loss, according to a randomized cross-over trial conducted by the Physicians Committee for Responsible Medicine and published inFrontiers in Nutrition.

"Eating acid-producing foods like meat, eggs, and dairy can increase the dietary acid load, or the amount of acids consumed, causing inflammation linked to weight gain," says Hana Kahleova, MD, PhD, director of clinical research at the Physicians Committee and lead author of the study. "But replacing animal products with plant-based foods like leafy greens, berries, and legumes can help promote weight loss and create a healthy gut microbiome."

This new research included 62 overweight adults who were randomized to a Mediterranean or a low-fat vegan diet for 16 weeks, separated by a four-week cleansing period, followed by an additional 16 weeks on the alternate diet.

Participants' dietary records were used to calculate dietary acid load, which is commonly estimated by two scores: Potential Renal Acid Load (PRAL) and Net Endogenous Acid Production (NEAP). A higher score indicates a higher dietary acid load.

Animal products including meat, fish, eggs, and cheese cause the body to produce more acid, increasing dietary acid load, which is linked to chronic inflammation that disrupts metabolism and can lead to increased body weight. Plant-based diets, which are more alkaline, are associated with weight loss, improved insulin sensitivity, and lower blood pressure.

In the new analysis, both PRAL and NEAP scores decreased significantly on the vegan diet, with no significant change on the Mediterranean diet. The reduction in dietary acid load was associated with weight loss, and this association remained significant even after adjustment for changes in energy intake. Body weight was reduced by 13.2 pounds on the vegan diet, compared with no change on the Mediterranean diet.

The authors say that a vegan diet's alkalizing effect, which increases the body's pH level to make it less acidic, may also help promote weight loss. Top alkalizing foods include vegetables, particularly leafy greens, broccoli, beets, asparagus, garlic, carrots, and cabbage; fruits, such as berries, apples, cherries, apricots, or cantaloupe; legumes, for example lentils, chickpeas, peas, beans or soy; and grains, such as quinoa or millet.

Founded in 1985, the Physicians Committee for Responsible Medicine is a nonprofit organization that promotes preventive medicine, conducts clinical research, and encourages higher standards for ethics and effectiveness in education and research.

Materials provided byPhysicians Committee for Responsible Medicine.Note: Content may be edited for style and length.

Cats prefer to sleep on their left side. This is the conclusion drawn by an international research team that analyzed several hundred YouTube videos of sleeping cats. The researchers see this bias as an evolutionary advantage because it favors hunting and escape behavior after waking up. The team from the University of Bari Aldo Moro (Italy), Ruhr University Bochum, Medical School Hamburg and other partners in Germany, Canada, Switzerland and Turkey report on the study in the journalCurrent Biology, published online on June 23, 2025.

All animals are particularly vulnerable while sleeping. Cats sleep around 12 to 16 hours a day, preferably in elevated places where their predators can only access them from below. The research team around Dr. Sevim Isparta from the Animal Physiology and Behaviour Research Unit in Bari and Professor Onur Güntürkün from the Bochum working group Biopsychology wanted to find out whether cats prefer to sleep on one side or the other. "Asymmetries in behavior can have advantages because both hemispheres of the brain specialize in different tasks," says Onur Güntürkün.

Perceiving dangers with the left visual field brings advantages

The group analyzed 408 publicly available YouTube videos in which a single cat was clearly visible with its entire body sleeping on one side for at least ten seconds. Only original videos were used; modified or flipped material was excluded from the study. Two thirds of the videos showed cats sleeping on their left side.

The explanation: Cats that sleep on their left side perceive their surroundings upon awakening with their left visual field, which is processed in the right hemisphere of the brain. This hemisphere is specialized in spatial awareness, the processing of threats and the coordination of rapid escape movements. If a cat sleeps on its left shoulder and wakes up, visual information about predators or prey goes directly to the right hemisphere of the brain, which is best in processing them. "Sleeping on the left side can therefore be a survival strategy," the researchers conclude.

Materialsprovided byRuhr-University Bochum.Note: Content may be edited for style and length.

Ultra-intense lasers can accelerate electrons to near-light speeds within a single oscillation (or 'wave cycle') of the electric field, making them a powerful tool for studying extreme physics. However, their rapid fluctuations and complex structure make real-time measurements of their properties challenging. Until now, existing techniques typically required hundreds of laser shots to assemble a complete picture, limiting our ability to capture the dynamic nature of these extreme light pulses.

Ultra-intense lasers can accelerate electrons to near-light speeds within a single oscillation (or 'wave cycle') of the electric field, making them a powerful tool for studying extreme physics. However, their rapid fluctuations and complex structure make real-time measurements of their properties challenging. Until now, existing techniques typically required hundreds of laser shots to assemble a complete picture, limiting our ability to capture the dynamic nature of these extreme light pulses.

The new study, jointly led by researchers in the University of Oxford's Department of Physics and the Ludwig-Maximilian University of Munich, Germany, describes a novel single-shot diagnostic technique, namedRAVEN(Real-time Acquisition of Vectorial Electromagnetic Near-fields). This method allows scientists to measure the full shape, timing, and alignment of individual ultra-intense laser pulses with high precision.

Having a complete picture of the laser pulse's behaviour could revolutionise performance gains in many areas. For example, it could enable scientists to fine-tune laser systems in real-time (even for lasers that fire only occasionally) and bridge the gap between experimental reality and theoretical models, providing better data for computer models and AI-powered simulations.

The method works by splitting the laser beam into two parts. One of these is used to measure how the laser's color (wavelength) changes over time, whilst the other part passes through a birefringent material (which separates light with different polarization states). A microlens array (a grid of tiny lenses) then records how the laser pulse's wavefront (shape and direction) is structured. The information is recorded by a specialized optical sensor, which captures it in a single image from which a computer program reconstructs the full structure of the laser pulse.

Lead researcher Sunny Howard (PhD researcher in the Department of Physics, University of Oxford and visiting scientist to Ludwig-Maximilian University of Munich) said: "Our approach enables, for the first time, the complete capture of an ultra-intense laser pulse in real-time, including its polarization state and complex internal structure. This not only provides unprecedented insights into laser-matter interactions but also paves the way for optimizing high-power laser systems in a way that was previously impossible."

The technique was successfully tested on theATLAS-3000 petawatt-class laserin Germany, where it revealed small distortions and wave shifts in the laser pulse that were previously impossible to measure in real-time, allowing the research team to fine-tune the instrument. These distortions, known asspatio-temporal couplings, can significantly affect the performance of high-intensity laser experiments.

By providing real-time feedback, RAVEN allows for immediate adjustments, improving the accuracy and efficiency of experiments in plasma physics, particle acceleration, and high-energy density science. It also results in significant time savings, since multiple shots are not required to fully characterize the laser pulse's properties.

The technique also provides a potential new route to realize inertial fusion energy devices in the laboratory – a key gateway step towards generating fusion energy at a scale sufficient to power societies. Inertial fusion energy devices use ultra-intense laser pulses to generate highly energetic particles within a plasma, which then propagate into the fusion fuel. This 'auxiliary heating' concept requires accurate knowledge of the focused laser pulse intensity to target to optimize the fusion yield, one now provided by RAVEN. Focused lasers could also provide a powerful probe for new physics – for instance, generating photon-photon scattering in a vacuum by directing two pulses at each other.

Co-author Professor Peter Norreys (Department of Physics, University of Oxford), says: "Where most existing methods would require hundreds of shots, RAVEN achieves a complete spatio-temporal characterization of a laser pulse in just one. This not only provides a powerful new tool for laser diagnostics but also has the potential to accelerate progress across a wide range of ultra-intense laser applications, promising to push the boundaries of laser science and technology."

Co-author Dr Andreas Döpp (Faculty of Physics, Ludwig-Maximilians-University Munich and visiting scientist to Atomic and Laser Physics, University of Oxford) adds: "Shortly after Sunny joined us in Munich for a year it finally 'clicked' and we realized the beautiful result underpinning RAVEN: that because ultra-intense pulses are confined to such a tiny space and time when focused, there are fundamental limits on how much resolution is actually needed to perform this type of diagnostic. This was a game changer, and meant we could use micro lenses, making our setup much simpler."

Looking ahead, the researchers hope to expand the use of RAVEN to a broader range of laser facilities and explore its potential in optimizing inertial fusion energy research,laser-driven particle acceleratorsandhigh-field quantum electrodynamics experiments.

This study was conducted in collaboration with Ludwig-Maximilian University of Munich, the Max Planck Institute for Quantum Optics, and the John Adams Institute for Accelerator Science. The work was supported by the UKRI-STFC and funding bodies in Germany and the European Union.

Materials provided byUniversity of Oxford.Note: Content may be edited for style and length.

Optical biosensors use light waves as a probe to detect molecules, and are essential for precise medical diagnostics, personalized medicine, and environmental monitoring. Their performance is dramatically enhanced if they can focus light waves down to the nanometer scale – small enough to detect proteins or amino acids, for example – using nanophotonic structures that 'squeeze' light at the surface of a tiny chip. But the generation and detection of light for these nanophotonic biosensors requires bulky, expensive equipment that greatly limits their use in rapid diagnostics or point-of-care settings.

So, how do you make a light-based biosensor without an external light source? The answer is: with quantum physics. By harnessing a quantum phenomenon called inelastic electron tunneling, researchers in the Bionanophotonic Systems Laboratory in EPFL's School of Engineering have created a biosensor that requires only a steady flow of electrons – in the form of an applied electrical voltage – to illuminate and detect molecules at the same time.

"If you think of an electron as a wave, rather than a particle, that wave has a certain low probability of 'tunneling' to the other side of an extremely thin insulating barrier while emitting a photon of light. What we have done is create a nanostructure that both forms part of this insulating barrier and increases the probability that light emission will take place," explains Bionanophotonic Systems Lab researcher Mikhail Masharin.

In short, the design of the team's nanostructure creates just the right conditions for an electron passing upward through it to cross a barrier of aluminum oxide and arrive at an ultrathin layer of gold. In the process, the electron transfers some of its energy to a collective excitation called a plasmon, which then emits a photon. Their design ensures that the intensity and spectrum of this light changes in response to contact with biomolecules, resulting in a powerful method for extremely sensitive, real-time, label-free detection.

"Tests showed that our self-illuminating biosensor can detect amino acids and polymers at picogram concentrations – that's one-trillionth of a gram – rivaling the most advanced sensors available today," says Bionanophotonic Systems Laboratory head Hatice Altug.

The work has been published inNature Photonicsin collaboration with researchers at ETH Zurich, ICFO (Spain), and Yonsei University (Korea).

At the heart of the team's innovation is a dual functionality: their nanostructure's gold layer is a metasurface, meaning it exhibits special properties that create the conditions for quantum tunneling, and control the resulting light emission. This control is made possible thanks to the metasurface's arrangement into a mesh of gold nanowires, which act as 'nanoantennas' to concentrate the light at the nanometer volumes required to detect biomolecules efficiently.

"Inelastic electron tunneling is a very low-probability process, but if you have a low-probability process occurring uniformly over a very large area, you can still collect enough photons. This is where we have focused our optimization, and it turns out to be a very promising new strategy for biosensing," says former Bionanophotonic Systems Lab researcher and first author Jihye Lee, now an engineer at Samsung Electronics.

In addition to being compact and sensitive, the team's quantum platform, fabricated at EPFL's Center of MicroNanoTechnology, is scalable and compatible with sensor manufacturing methods. Less than a square millimeter of active area is required for sensing, creating an exciting possibility for handheld biosensors, in contrast to current table-top setups.

"Our work delivers a fully integrated sensor that combines light generation and detection on a single chip. With potential applications ranging from point-of-care diagnostics to detecting environmental contaminants, this technology represents a new frontier in high-performance sensing systems," summarizes Bionanophotonic Systems Lab researcher Ivan Sinev.

Materialsprovided byEcole Polytechnique Fédérale de Lausanne.Note: Content may be edited for style and length.

Scientists from TU Delft (The Netherlands) have observed quantum spin currents in graphene for the first time without using magnetic fields. These currents are vital for spintronics, a faster and more energy-efficient alternative to electronics. This breakthrough, published inNature Communications, marks an important step towards technologies like quantum computing and advanced memory devices.

Quantum physicist Talieh Ghiasi has demonstrated the quantum spin Hall (QSH) effect in graphene for the first time without any external magnetic fields. The QSH effect causes electrons to move along the edges of the graphene without any disruption, with all their spins pointing in the same direction. "Spin is a quantum mechanical property of electrons, which is like a tiny magnet carried by the electrons, pointing up or down," Ghiasi explains. "We can leverage the spin of electrons to transfer and process information in so-called spintronics devices. Such circuits hold promise for next-generation technologies, including faster and more energy-efficient electronics, quantum computing, and advanced memory devices."

Realizing quantum transport in graphene typically requires applying large external magnetic fields that are not compatible with electronic circuitries. "In particular, the detection of quantum spin currents in graphene has always required large magnetic fields that are practically impossible to integrate on-chip. Thus, the fact that we are now achieving the quantum spin currents without the need for external magnetic fields opens the path for the future applications of these quantum spintronic devices," says Ghiasi.

The scientists from the Van der Zant lab were able to bypass the need for external fields by layering the graphene on top of a magnetic material: CrPS₄. This magnetic layer significantly altered the graphene's electronic properties, giving rise to the QSH effect in graphene. Ghiasi: "We observed that the spin transport in graphene gets modified by the neighboring CrPS4such that the flow of electrons in graphene becomes dependent on the electrons' spin direction."

The quantum spin currents that the scientists detect in the graphene-CrPS4stack are 'topologically' protected, implying that the spin signal travels stays intact over tens of micrometers long distances without losing the spin information in the circuit."These topologically-protected spin currents are robust against disorders and defects, making them reliable even in imperfect conditions," Ghiasi says. Preserving spin signal without any loss of information is vital for building spintronic circuits.

This discovery paves the way toward ultrathin, graphene-based spintronic circuits, promising advancements in next-generation memory and computing technologies. The observed spin currents in graphene offer a powerful new route for efficient and coherent transfer of quantum information through electron spins. These robust spintronic devices could serve as essential building blocks in quantum computing, seamlessly linking qubits together within quantum circuits.

Materialsprovided byDelft University of Technology.Note: Content may be edited for style and length.

An interdisciplinary team of experts in green chemistry, engineering and physics at Flinders University in Australia has developed a safer and more sustainable approach to extract and recover gold from ore and electronic waste.

Explained in the leading journalNature Sustainability, the gold-extraction technique promises to reduce levels of toxic waste from mining and shows that high purity gold can be recovered from recycling valuable components in printed circuit boards in discarded computers.

The project team, led by Matthew Flinders Professor Justin Chalker, applied this integrated method for high-yield gold extraction from many sources – even recovering trace gold found in scientific waste streams.

The progress toward safer and more sustainable gold recovery was demonstrated for electronic waste, mixed-metal waste, and ore concentrates.

"The study featured many innovations including a new and recyclable leaching reagent derived from a compound used to disinfect water," says Professor of Chemistry Justin Chalker, who leads the Chalker Lab at Flinders University's College of Science and Engineering.

"The team also developed an entirely new way to make the polymer sorbent, or the material that binds the gold after extraction into water, using light to initiate the key reaction."

Extensive investigation into the mechanisms, scope and limitations of the methods are reported in the new study, and the team now plans to work with mining and e-waste recycling operations to trial the method on a larger scale.

"The aim is to provide effective gold recovery methods that support the many uses of gold, while lessening the impact on the environment and human health," says Professor Chalker.

The new process uses a low-cost and benign compound to extract the gold. This reagent (trichloroisocyanuric acid) is widely used in water sanitation and disinfection. When activated by salt water, the reagent can dissolve gold.

Next, the gold can be selectively bound to a novel sulfur-rich polymer developed by the Flinders team. The selectivity of the polymer allows gold recovery even in highly complex mixtures.

The gold can then be recovered by triggering the polymer to "un-make" itself and convert back to monomer. This allows the gold to be recovered and the polymer to be recycled and re-used.

Global demand for gold is driven by its high economic and monetary value but is also a vital element in electronics, medicine, aerospace technologies and other products and industries. However, mining the previous metal can involve the use of highly toxic substances such as cyanide and mercury for gold extraction – and other negative environmental impacts on water, air and land including CO2emissions and deforestation.

The aim of the Flinders-led project was to provide alternative methods that are safer than mercury or cyanide in gold extraction and recovery.

The team also collaborated with experts in the US and Peru to validate the method on ore, in an effort to support small-scale mines that otherwise rely on toxic mercury to amalgamate gold.

Gold mining typically uses highly toxic cyanide to extract gold from ore, with risks to the wildlife and the broader environment if it is not contained properly. Artisanal and small-scale gold mines still use mercury to amalgamate gold. Unfortunately, the use of mercury in gold mining is one of the largest sources of mercury pollution on Earth.

Professor Chalker says interdisciplinary research collaborations with industry and environmental groups will help to address highly complex problems that support the economy and the environment.

"We are especially grateful to our engineering, mining, and philanthropic partners for supporting translation of laboratory discoveries to larger scale demonstrations of the gold recovery techniques."

Lead authors of the major new study – Flinders University postdoctoral research associates Dr Max Mann, Dr Thomas Nicholls, Dr Harshal Patel and Dr Lynn Lisboa – extensively tested the new technique on piles of electronic waste, with the aim of finding more sustainable, circular economy solutions to make better use of ever-more-scarce resources in the world. Many components of electronic waste, such as CPU units and RAM cards, contain valuable metals such as gold and copper.

Dr Mann says: "This paper shows that interdisciplinary collaborations are needed to address the world's big problems managing the growing stockpiles of e-waste."

ARC DECRA Fellow Dr Nicholls, adds: "The newly developed gold sorbent is made using a sustainable approach in which UV light is used to make the sulfur-rich polymer. Then, recycling the polymer after the gold has been recovered further increases the green credentials of this method."

Dr Patel says: "We dived into a mound of e-waste and climbed out with a block of gold! I hope this research inspires impactful solutions to pressing global challenges."

"With the ever-growing technological and societal demand for gold, it is increasingly important to develop safe and versatile methods to purify gold from varying sources," Dr Lisboa concludes.

Electronic waste (e-waste) is one of the fastest growing solid waste streams in the world. In 2022, an estimated 62 million tonnes of e-waste was produced globally. Only 22.3% was documented as formally collected and recycled.

E-waste is considered hazardous waste as it contains toxic materials and can produce toxic chemicals when recycled inappropriately. Many of these toxic materials are known or suspected to cause harm to human health, and several are included in the 10 chemicals of public health concern, including dioxins, lead and mercury. Inferior recycling of e-waste is a threat to public health and safety.

Miners use mercury, which binds to gold particles in ores, to create what are known as amalgams. These are then heated to evaporate the mercury, leaving behind gold but releasing toxic vapours. Studies indicate that up to 33% of artisanal miners suffer from moderate metallic mercury vapor intoxication.

Between 10 million and 20 million miners in more than 70 countries work in artisanal and small-scale gold mining, including up to 5 million women and children. These operations, which are often unregulated and unsafe, generate 37% of global mercury pollution (838 tonnes a year) – more than any other sector.

Most informal sites lack the funding and training needed to transition towards mercury-free mining. Despite accounting for 20% of the global gold supply and generating approximately US$30 billion annually, artisanal miners typically sell gold at around 70% of its global market value. Additionally, with many gold mines located in rural and remote areas, miners seeking loans are often restricted to predatory interest rates from illegal sources, pushing demand for mercury.

Materials provided byFlinders University.Note: Content may be edited for style and length.

Fatty liver disease, caused by the accumulation of fat in the liver, is estimated to affect one in four people worldwide. If left untreated, it can lead to serious complications, such as cirrhosis and liver cancer, making it crucial to detect early and initiate treatment.

Currently, standard tests for diagnosing fatty liver disease include ultrasounds, CTs, and MRIs, which require costly specialized equipment and facilities. In contrast, chest X-rays are performed more frequently, are relatively inexpensive, and involve low radiation exposure. Although this test is primarily used to examine the condition of the lungs and heart, it also captures part of the liver, making it possible to detect signs of fatty liver disease. However, the relationship between chest X-rays and fatty liver disease has rarely been a subject of in-depth study.

Therefore, a research group led by Associate Professor Sawako Uchida-Kobayashi and Associate Professor Daiju Ueda at Osaka Metropolitan University's Graduate School of Medicine developed an AI model that can detect the presence of fatty liver disease from chest X-ray images.

In this retrospective study, a total of 6,599 chest X-ray images containing data from 4,414 patients were used to develop an AI model utilizing controlled attenuation parameter (CAP) scores. The AI model was verified to be highly accurate, with the area under the receiver operating characteristic curve (AUC) ranging from 0.82 to 0.83.

"The development of diagnostic methods using easily obtainable and inexpensive chest X-rays has the potential to improve fatty liver detection. We hope it can be put into practical use in the future," stated Professor Uchida-Kobayashi.

Materialsprovided byOsaka Metropolitan University.Note: Content may be edited for style and length.