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Chemical shifts help track molecules breaking apart in real time

When molecules fall apart, their electric charge doesn’t stay put—it rearranges as bonds stretch and break. An international team of scientists has now tracked these ultrafast changes in the small molecule fluoromethane (CH₃F). It was the first time that the Small Quantum Systems (SQS) instrument at European XFEL could deliver detailed insights into transient states during chemical reactions. The research is published in the journal Physical Review X.

These intermediate states, that only exist temporarily while the reaction is ongoing, are often the key drivers of chemistry and therefore crucial to understand. Over the long term, that kind of insight can support progress in areas such as atmospheric science (where sunlight-driven reactions and fragmentation pathways shape air chemistry), as well as the study of complex molecular systems including biomolecules and proteins, where local excitation and charge transfer can trigger structural change.

In the experiment, the researchers first triggered the reaction with an optical laser pulse. Next, they used the X-ray laser pulses that the European XFEL produces, to eject an electron from the core of either the fluorine or the carbon atom in the molecule. They measured the electron’s kinetic energy, which reveals how strongly it was bound inside the atom. That binding energy is extremely sensitive to the local electrical environment, producing so-called “chemical shifts” that act like a fingerprint of the charge distribution surrounding the atom from which the electron has been ejected.

Mining the dark transcriptome: Synthesizing the first potential drug molecules from long noncoding RNA

A team from University of Toronto Engineering is the first to synthesize long noncoding RNA (lncRNA) outside the cell—a new approach to drug discovery that has already yielded some promising anti-inflammatory molecules. The team was inspired by advances in the field of messenger RNA (mRNA) and protein replacement therapies. They realized that a similar approach could be used to deliver lncRNA to the body, unlocking a potential new source of drugs.

“Only about 25% of our DNA encodes for proteins, including everything from insulin for regulating blood sugar to antibodies for immune defense,” says Professor Omar F. Khan, senior author on a paper published in Science Signaling that describes the new discovery.

“Proteins are made via messenger RNA, or mRNA, which conveys the instructions for how to build proteins from our genes to our ribosomes, the part of our cells where proteins are assembled.”

Why anger feels close to fear: Brain charts emotion in a map-like way

It is well established in psychology that humans conceptualize emotions by features known as valence (the degree of pleasantness or unpleasantness) and arousal (the intensity of bodily reactions, such as rapid breathing or a racing heart).

If you think of “pleasantness” as longitude and “bodily reaction” as latitude, you can imagine a “mental map,” with nodes that “chart” knowledge of emotion.

The neural mechanisms giving rise to this configuration, however, have remained unclear.

Precisely measuring quantum signals in large spin ensembles

Quantum mechanical effects are known to be easily disrupted by disturbances from the surrounding environment, commonly referred to as noise. To minimize these disturbances, physicists often study these effects in small and carefully controlled systems, in which environmental noise can be minimized.

Researchers at Johns Hopkins University set out to study quantum effects in macroscopic spin ensembles, systems comprised of large numbers of spins (spins is the intrinsic angular momentum of elementary particles). Their paper, published in Nature Physics, introduces a new approach to directly observe quantum spin fluctuations in macroscopic spin ensembles, precisely monitoring their evolution over time.

“Quantum effects are typically observed and exploited in microscopic systems, where individual qubits can be precisely controlled and measured,” Alexander O. Sushkov, senior author of the paper, told Phys.org.

Opening the path to high-efficiency hydrogen production without expensive precious metals

A research team has successfully designed and developed a proprietary non-precious metal oxygen evolution reaction (OER) catalyst featuring a layered structure optimized for anion exchange membrane water electrolysis (AEMWE) environments.

The study, published in the journal ACS Nano, is particularly significant in that it proposes a novel catalyst design strategy capable of simultaneously achieving high efficiency and durability while reducing reliance on expensive precious metal catalysts. The team was led by Dr. Sung Mook Choi of the Energy & Environment Materials Research Division at the Korea Institute of Materials Science (KIMS), in collaboration with a team headed by Professor Seung-Hwa Lee at Changwon National University.

Anion exchange membrane water electrolysis (AEMWE) operates under alkaline conditions, offering a structural advantage in that relatively low-cost non-precious metal catalysts can be employed in place of expensive precious metals. For this reason, AEMWE has attracted considerable attention as a cost-effective and inherently safe hydrogen production technology.

Scientists harness quantum tunneling to boost heavy water production efficiency

A study by scientists at Hunan University introduces a new hydrogen isotope separation method that leverages proton quantum tunneling to produce heavy water, overcoming the key physical limitation faced by current methods that have made the production process difficult and expensive for decades.

According to results published in Proceedings of the National Academy of Sciences, this new strategy achieves a record-high H2O separation factor of 276 at room temperature by designing through-barriers that allow hydrogen nuclei to pass through them via quantum tunneling, leaving deuterium behind.

By leveraging quantum mechanics, the method could pave the way for cleaner and more efficient production of a critical material for future energy technologies.

3D imaging reveals messy-looking supraparticles can be nearly perfect crystals inside

Researchers at Utrecht University have quantitatively mapped the three-dimensional structure of photonic supraparticles for the first time. Supraparticles are microscopic spheres composed of thousands of smaller colloidal particles. Until now, researchers could only examine the outer surface of these structures. Using a combination of super-resolution microscopy and machine learning, the team shows that particles that appear disorganized on the outside are often almost perfectly crystalline on the inside.

The paper is published in the journal Advanced Materials.

Blue morpho butterflies owe their vibrant color to the internal structure of their wings, rather than pigment. The arrangement of particles on a microscopic scale causes light to be reflected in such a way that the butterflies appear intensely blue, and that the color looks the same from every viewing angle.

3D-printed photonic lanterns combine up to 37 multimode lasers into one fiber

Researchers have developed a microscopic 3D-printed optical device that can efficiently combine light from dozens of small semiconductor lasers into a single multimode optical fiber with very low loss. The team demonstrated photonic lanterns that multiplex 7, 19, and 37 multimode VCSEL lasers directly into a fiber while preserving brightness and easing alignment constraints. By enabling scalable incoherent beam combining of many multimode lasers, the technology could simplify and improve high-power laser systems, optical communications, and other photonic applications where efficiently delivering large optical power through fibers is critical.

A new study published in Nature Communications by Ph.D. student Yoav Dana, under the guidance of Professor Dan M. Marom and his team at the Institute of Applied Physics at the Hebrew University of Jerusalem, Israel, demonstrate a significant breakthrough in system scale and miniaturization for an optical beam combining apparatus, as those required in high-power laser systems.

The research, conducted in collaboration with Civan Lasers, introduces a novel 3D-printed microscale Photonic Lantern (PL) designed for the efficient incoherent combining of multimode sources. This innovation addresses the long-standing challenge of coupling light from large Vertical-Cavity Surface-Emitting Laser (VCSEL) arrays, each of said VCSEL sources being multimoded, into multimode fibers (MMFs) while preserving the brightness and modal capacity of the system.

Electron microscopy maps protein landscapes that drive photosynthesis

Research led by scientists at Washington State University has revealed insights on how plants form a microscopic landscape of proteins crucial to photosynthesis, the basis of Earth’s food and energy chain. The discovery provides a new view of the molecular engine that converts sunlight into bioenergy and could enable future fine-tuning of crops for higher yields and other useful traits.

Colleagues at WSU, the University of Texas at Austin, and the Weizmann Institute of Science in Israel used a novel, technology-powered approach to peer inside plant leaf cells and visualize the landscape of the photosynthetic membrane—the ribbon-like structure where plants harvest sunlight. The findings were recently published in the journal Science Advances.

“These membranes are highly efficient biological solar cells,” said the study’s principal investigator and corresponding author, Helmut Kirchhoff. “They convert sunlight energy into chemical energy that fuels not only the plant’s metabolism but that of most life on Earth.”

Scientists control ‘free-flowing’ electric currents with light

By controlling magnetic fields using light, a team of researchers led by NTU scientists has solved a long-standing challenge to precisely direct electric currents produced by quantum materials. Their findings unlock new avenues for controlling the flow of electricity through such materials and could herald the age of energy-efficient quantum computing devices. The research is published in Nature in January.

Like water moving through lakes and rivers, electrons in electric currents encounter resistance when flowing through electronic devices. This resistance generates large amounts of heat, which poses a problem for large computing facilities such as data centers and quantum computers, incurring major costs for cooling.

With artificial intelligence driving the demand for more computing applications, there is a need to produce electricity that flows without resistance to avoid generating excessive amounts of heat. These “free-flowing” electric currents could pave the way for novel low-power electronics and new quantum computing technologies.

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