Lifeboat Foundation

A whitish, gray patch that sometimes appears in the night sky alongside the northern lights has been explained for the first time by researchers at the University of Calgary.

The article, which was published on Dec. 30 in the journal Nature Communications, explores a “structured continuum emission” that’s associated with aurora borealis.

“You’d see this dynamic green aurora, you’d see some of the red aurora in the background and, all of a sudden, you’d see this structured—almost like a patch—gray-toned or white toned-emission connected to the aurora,” says Dr. Emma Spanswick, Ph.D., lead author on the paper and an associate professor with the Department of Physics and Astronomy in the Faculty of Science.

Normandie University researchers have identified critical links between the brain’s inhibitory memory control mechanisms and resilience to post-traumatic stress disorder (PTSD). They examined how the hippocampus and prefrontal memory control processes adapt over time in individuals exposed to trauma, with findings suggesting that the plasticity of these systems supports recovery from PTSD and protects against further neurological damage.

PTSD involves intrusive memories and emotional distress following trauma, with significant attention previously focused on stress vulnerability and hippocampal alterations. The hippocampus, critical for memory processing, is highly susceptible to stress, which can result in structural and functional impairments.

Brain resilience is the process that mitigates stress effects and involves neuroplasticity, or the brain’s ability to reorganize itself. The specific neural mechanisms underlying resilience have remained unclear, though outcomes related to regional brain activation have been observed.

The human working memory (WM) is the cognitive system responsible for the temporary storage and processing of information vital to task completion. In contrast, human long-term memory (LTM) is the system that holds information for prolonged periods of time, organizing acquired knowledge into distinct categories, such as facts, events, skills and habits.

For decades, most psychologists and neuroscientists have viewed these two memory components as separate systems, one tackling short-term and the other long-term tasks, supported by distinct neural processes. Therefore, most studies conducted so far have focused on only one of these systems, instead of exploring the potential connections between working memory and long-term memory processes.

Researchers at the Cedars-Sinai Medical Center and other institutes recently set out to simultaneously investigate the neural underpinnings of both WM and LTM, to determine whether these systems utilize some common mechanisms to store information. Their findings, published in Neuron, suggest that the two systems interact in the hippocampus, with persistent WM activity predicting the formation of LTM.

Researchers at the University of Tokyo have demonstrated that the direction of the spin-polarized current can be restricted to only one direction in a single-atom layer of a thallium-lead alloy when irradiated at room temperature. The discovery defies conventions: single-atom layers have been thought to be almost completely transparent, in other words, negligibly absorbing or interacting with light.

The one-directional flow of the current observed in this study makes possible functionality beyond ordinary diodes, paving the way for more environmentally friendly data storage, such as ultra-fine two-dimensional spintronic devices, in the future. The findings are published in the journal ACS Nano.

Diodes are fundamental building blocks of modern electronics by restricting the flow of currents to only one direction. However, the thinner the device, the more complicated it becomes to design and manufacture these functional components. Thus, demonstrating phenomena that might make such developmental feats possible is critical. Spintronics is an area of study in which researchers manipulate the intrinsic angular momentum (spin) of electrons, for example, by applying light.

The development of sustainable energy sources that can satisfy the world energy demand is one of the most challenging scientific problems. Nuclear fusion, the energy source of stars, is a clean and virtually unlimited energy source that appears as a promising candidate.

The most promising fusion reactor design is based on the tokamak concept, which uses magnetic fields to confine the plasma. Achieving high confinement is key to the development of nuclear fusion power plants and is the final aim of ITER, the largest tokamak in the world currently under construction in Cadarache (France).

The plasma edge stability in a tokamak plays a fundamental role in plasma confinement. In present-day tokamaks, edge instabilities, magnetohydrodynamic waves known as ELMs (edge localized modes), lead to significant particle and energy losses, like solar flares on the edge of the sun. The particle and energy losses due to ELMs can cause erosion and excessive heat fluxes onto the plasma-facing components, at levels unacceptable in future burning plasma devices.

Electron transport in bilayer graphene exhibits a pronounced dependence on edge states and a nonlocal transport mechanism, according to a study led by Professor Gil-Ho Lee and Ph.D. candidate Hyeon-Woo Jeong of POSTECH’s Department of Physics, in collaboration with Dr. Kenji Watanabe and Dr. Takashi Taniguchi at Japan’s National Institute for Materials Science (NIMS).

The findings are published in the journal Nano Letters.

Bilayer graphene, comprising two vertically stacked graphene layers, can exploit externally applied electric fields to modulate its electronic band gap—a property essential for electron transport. This distinctive feature has drawn considerable attention for its prospective role in “valleytronics,” an emerging paradigm for next-generation data processing.

Molecular crystals with conductivity and magnetism, due to their low impurity concentrations, provide valuable insights into valence electrons. They have helped link charge ordering to superconductivity and to explore quantum spin liquids, where electron spins remain disordered even at extremely low temperatures.

Valence electrons with quantum properties are also expected to exhibit emergent phenomena, making these crystals essential for studying novel material functionalities.

However, the extent to which valence electrons in molecular crystals contribute to magnetism remains unclear, leaving their quantum properties insufficiently explored. To address this, a research team used light to analyze valence electron arrangements, building on studies of superconductors and quantum spin liquids. The findings are published in Physical Review B.

Bimetallic particles, made from a combination of a noble metal and a base metal, have unique catalytic properties that make them highly effective for selective heterogeneous hydrogenation reactions. These properties arise from their distinctive geometric and electronic structures. For hydrogenation to be both effective and selective, it requires specific interactions at the molecular level, where the active atoms on the catalyst precisely target the functional group in the substrate for transformation.

Nanoscale Engineering and Electronic Structure Tuning

Scaling these particles down to nanoscale atomic clusters or single-atom alloys further enhances their catalytic performance. This reduction in size increases surface dispersion and optimizes the use of noble metal atoms. Additionally, these nanoscale changes alter the electronic structure of the active sites, which can significantly influence the activity and selectivity of the reaction. By carefully adjusting the bonding between noble metal single atoms and the base metal host, researchers can create flexible environments that fine-tune the electronic properties needed to activate specific functional groups. Despite these advances, achieving atomically precise fabrication of such active sites remains a significant challenge.

Galactic gravity can dramatically impact wide binary stars, pushing them towards unexpected mergers or collisions.

The detection of gravitational waves.

Gravitational waves are distortions or ripples in the fabric of space and time. They were first detected in 2015 by the Advanced LIGO detectors and are produced by catastrophic events such as colliding black holes, supernovae, or merging neutron stars.