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Researchers at the University of Bayreuth have developed a method that makes objects on a magnetic field invisible within a particle stream. Until now, this so-called cloaking had only been studied for waves such as light or sound. They report their results in Nature Communications.

Making objects invisible is no longer a purely fictional idea from fantasy or sci-fi films. At least to some extent, cloaking also works in research: manipulating objects in such a way that they become invisible to certain waves such as light or sound.

The Bayreuth researchers are extending cloaking to particle motions. Cloaking for particle streams on miniaturized chemical laboratories, so-called lab-on-a-chip devices, can help to transport active ingredients in a targeted manner without exposing them to undesirable premature chemical reactions.

ETH Zurich researchers have investigated how tiny gas bubbles can deliver drugs into cells in a targeted manner using ultrasound. For the first time, they have visualized how tiny cyclic microjets liquid jets generated by microbubbles penetrate the cell membrane, enabling the drug uptake.

The targeted treatment of brain diseases such as Alzheimer’s, Parkinson’s or brain tumors is challenging because the brain is a particularly sensitive organ that is well protected. That’s why researchers are working on ways of delivering drugs to the brain precisely, via the bloodstream. The aim is to overcome the blood–brain barrier, which normally only allows certain nutrients and oxygen to pass through.

Microbubbles that react to ultrasound are a particularly promising method for this sort of therapy. These microbubbles are smaller than a , are filled with gas and have a special coating of fat molecules to stabilize them. They are injected into the bloodstream together with the drug and then activated at the target site using ultrasound. The movement of the microbubbles creates tiny pores in the cell membrane of the blood vessel wall that the drug can then pass through.

Rain can freefall at speeds of up to 25 miles per hour. If the droplets land in a puddle or pond, they can form a crown-like splash that, with enough force, can dislodge any surface particles and launch them into the air.

Now MIT scientists have taken high-speed videos of droplets splashing into a deep pool, to track how the fluid evolves, above and below the water line, frame by millisecond frame. Their work could help to predict how spashing droplets, such as from rainstorms and irrigation systems, may impact watery surfaces and aerosolize surface particles, such as pollen on puddles or pesticides in agricultural runoff.

The team carried out experiments in which they dispensed water droplets of various sizes and from various heights into a pool of water. Using high-speed imaging, they measured how the liquid pool deformed as the impacting droplet hit the pool’s surface.

Optical atomic clocks can increase the precision of time and geographic position a thousandfold in our mobile phones, computers, and GPS systems. However, they are currently too large and complex to be widely used in society.

Now, a research team from Purdue University, U.S., and Chalmers University of Technology, Sweden, has developed a technology that, with the help of on-chip microcombs, could make ultra-precise optical atomic clock systems significantly smaller and more accessible—with significant benefits for navigation, autonomous vehicles, and geo-data monitoring.

The research is published in the journal Nature Photonics.

The practice of purposely looping thread to create intricate knit garments and blankets has existed for millennia. Though its precise origins have been lost to history, artifacts like a pair of wool socks from ancient Egypt suggest it dates back as early as the third to fifth century CE. Yet, for all its long-standing ubiquity, the physics behind knitting remains surprisingly elusive.

“Knitting is one of those weird, seemingly simple but deceptively complex things we take for granted,” says and visiting scholar at the University of Pennsylvania, Lauren Niu, who recently took up the craft as a means to study how “geometry influences the mechanical properties and behavior of materials.”

Despite centuries of accumulated knowledge, predicting how a particular knit pattern will behave remains difficult—even with modern digital tools and automated knitting machines. “It’s been around for so long, but we don’t really know how it works,” Niu notes. “We rely on intuition and trial and error, but translating that into precise, predictive science is a challenge.”

A team of engineers and physicists at Southern University of Science and Technology, in China, has created a nickel-based material that behaves as a superconductor above the −233°C (40 K) threshold under ambient pressure. In their study published in Nature, the researchers synthesized thin films of bilayer nickelate (La₂.₈₅Pr₀.₁₅Ni₂O₇) and found one that behaved as a high-temperature superconductor.

The −233°C threshold (40 K), often associated with the McMillan limit, marks a boundary beyond which conventional superconductivity theories become less predictive.

Scientists have been searching for a room-temperature superconductor that could revolutionize a wide range of technologies. The ability to achieve superconductivity without the need for costly and complex cooling systems would significantly reduce energy loss due to heat conversion in electrical transmission, leading to dramatic improvements in efficiency and cost reduction. This breakthrough could lead to advancements in numerous fields, including maglev trains, fusion reactors and MRI machine components. This new effort by the team in China represents another step in reaching the ultimate goal.

The Standard Model ℠, the main physics framework describing elementary particles and the forces driving them, outlines key patterns in physical interactions referred to as gauge symmetries. One of the symmetries it describes is the so-called UY hypercharge: a gauge symmetry that contributes to the electric charge of particles before electromagnetic and weak forces become distinct (i.e., before the electroweak phase transition).

Researchers at Universidad Autónoma de Madrid’s Theoretical Physics Department (DFT) and Instituto de Física Teórica (IFT) recently carried out a study investigating how the conditions present in the early universe could prompt the spontaneous breaking of this gauge symmetry, linking this phenomenon to certain models of neutrino mass generation known as radiative neutrino mass models. Their paper, published in Physical Review Letters, specifically builds on a theoretical framework called the Zee-Babu model, an extension of the SM explaining neutrino mass generation.

“In the SM, the spontaneously broken electroweak gauge symmetry, which governs the electromagnetic and weak interactions of nature, was restored in the universe’s first instants, when the universe’s temperature was higher than the electroweak energy scale,” Prof. Jose Miguel No, Luca Merlo, Alvaro Lozano-Onrubia and Sergio López-Zurdo told Phys.org.

An early-career physicist mathematically connects timelike and spacelike form factors, opening the door to further insights into the inner workings of the strong force. A new lattice QCD calculation connects two seemingly disparate reactions involving the pion, the lightest particle governed by the strong interaction.

As an undergraduate student at Tecnológico de Monterrey in Mexico, Felipe Ortega-Gama worked at the U.S. Department of Energy’s Thomas Jefferson National Accelerator Facility as part of the Science Undergraduate Laboratory Internships program. There, Ortega-Gama worked with Raúl Briceño, who was a jointly appointed staff scientist in the lab’s Center for Theoretical and Computational Physics (Theory Center) and professor at Old Dominion University.

Briceño introduced him to quantum chromodynamics (QCD), the theory that describes the strong interaction. This is the force that binds quarks and gluons together to form protons, neutrons and other particles generically called hadrons. Theorists use lattice QCD, a computational method for solving QCD, to make predictions based on this theory. These predictions are then used to help interpret the results of experiments involving hadrons.

An international research collaboration led by the University of Surrey’s Nuclear Physics Group has overturned the long-standing belief that the atomic nucleus of lead-208 (²⁰⁸Pb) is perfectly spherical. The discovery challenges fundamental assumptions about nuclear structure and has far-reaching implications for our understanding of how the heaviest elements are formed in the universe.

Lead-208 is exceptionally stable due to being a “doubly magic” nucleus—and is the heaviest that we know of. However, a new study published in Physical Review Letters used a high-precision experimental probe to examine its shape and found that rather than being perfectly spherical, the nucleus of lead-208 is slightly elongated, resembling a rugby ball (prolate spheroid).

Dr. Jack Henderson, principal investigator of the study from the University of Surrey’s School of Mathematics and Physics, said, “We were able to combine four separate measurements using the world’s most sensitive experimental equipment for this type of study, which is what allowed us to make this challenging observation. What we saw surprised us, demonstrating conclusively that lead-208 is not spherical, as one might naively assume. The findings directly challenge results from our colleagues in nuclear theory, presenting an exciting avenue for future research.”

University of California, Los Angeles researchers have discovered that chronic stress flips brain activity between two amygdala-striatal pathways, disrupting flexible decision-making and promoting inflexible habits.

The research identifies distinct roles for the –dorsomedial striatum (BLA→DMS) and central amygdala–dorsomedial striatum (CeA→DMS) circuits in action-outcome learning and habit formation.

Chronic stress impairs goal-directed decision-making, often leading to rigid, habitual behaviors that underpin several psychiatric conditions. Understanding the involved could illuminate vulnerabilities in disorders like substance use, , and depression.