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Early warning sign of Alzheimer’s!

When most people think about Alzheimer’s disease, memory loss is usually the first thing that comes to mind. Forgetting a loved one’s name, missing appointments or repeatedly misplacing everyday items are often considered early warning signs.

But what if the disease begins affecting the brain long before memory problems become noticeable? New research suggests that another change in brain function may appear even earlier: difficulty adapting when circumstances change.

In a recent study, researchers found that animal models with Alzheimer’s-related brain changes developed problems with cognitive flexibility months before they showed signs of memory impairment. Cognitive flexibility refers to the brain’s ability to adjust behavior, learn new rules and adapt when situations change.

Proteomics Analysis of Peripheral Blood Mononuclear Cells from Patients in Early Dengue Infection Reveals Potential Markers of Subsequent Fluid Leakage

Infections caused by dengue virus (DENV) result in significant morbidity and mortality. A proportion of infected individuals develop dengue haemorrhagic fever (DHF) characterized by circulatory collapse and multiorgan failure. Early detection of individuals likely to develop DHF could lead to improved outcomes for patients and help us use healthcare resources more efficiently. We identified proteins that are differentially regulated during early disease in peripheral blood mononuclear cells (PBMCs) of patients who subsequently developed DHF. Four dengue fever (DF), four DHF and two healthy control PBMCs were subjected to tandem mass tag mass spectrometry. Differentially regulated proteins were used to identify up- or down-regulated Gene Ontology pathways. One hundred and sixty proteins were differentially expressed in DENV-infected samples compared to healthy controls. PBMCs from DHF patients differentially expressed 90 proteins compared to DF; these were involved in down-regulation of platelet activation and aggregation, cell adhesion, and cytoskeleton arrangement pathways. Proteins involved in oxidative stress and p38 MAPK signalling were upregulated in DHF samples during early infection compared to DF. This study has identified 90 proteins differentially regulated in PBMCs that could potentially serve as biomarkers to identify patients at risk of developing DHF at an early disease stage.

Evidence of elusive high-energy gravitons in quantum Hall systems

Electrons, negatively charged particles, sometimes coordinate their movements in ways that produce certain collective excitations referred to as quasiparticles. One case in which this occurs is the quantum Hall effect, a phenomenon that emerges when electrons are confined to a very thin layer, cooled to temperatures around 0 kelvin and exposed to a very strong magnetic field.

A framework called parton theory hypothesized the existence of emergent partons (i.e., quark-like quasiparticles in condensed matter physics that should not be confused with quarks and gluons in particle physics) to explain the collective excitations of quantum Hall states.

Recent geometric theoretical frameworks also suggest that small fluctuations in a system’s quantum metric (i.e., a quantity describing the ‘shape’ of a quantum state) produce collective spin-2 excitations referred to as chiral gravitons.

Baseline tool could separate alien life signals from geology on ocean worlds

When it comes to the search for life elsewhere in the universe, methane and other chemical compounds are seen as signs of biology because they are often produced by living microbes. However, scientists can be misled because certain geological processes can produce chemical signatures identical to those of living organisms.

To help identify true biological signals and reduce the risk of false detections, researchers have developed a framework that models what a planet’s chemistry looks like without life.

Their research is published in the journal Nature Astronomy.

Saturn-ring-like laser emission from chiral polymeric microspheres

Controlling light within microscopic spaces is crucial for next-generation optical devices such as photonic integrated circuits and localized sensors. Microspheres formed of luminescent π-conjugated polymers act as optical resonators that confine and amplify light via whispering gallery modes (WGMs), and they are promising candidates for microscale organic lasers and photonic applications. However, conventional microsphere resonators are geometrically isotropic and emit isotropic light, making directional control of emissions challenging.

In a new study published in the Journal of the American Chemical Society, researchers from the University of Tsukuba show that microspheres formed through the self-assembly of chiral π-conjugated polymers possess a characteristic twisted bipolar molecular configuration, enabling angle-selective optical resonance and laser oscillation with distinct azimuthal directionality. Using polarization-dependent photoluminescence imaging, the research team directly visualized a vortex-like (swirling) arrangement formed by the polymer main chains on the spherical surface.

Furthermore, this vortex-like surface molecular orientation induces an azimuth-dependent refractive-index distribution along the light propagation path, resulting in angle-dependent WGM resonance wavelengths and spatially localized emission. Consequently, the microspheres exhibit directional laser oscillation, preferentially emitting amplified light along a specific azimuthal direction. The resulting emission pattern is analogous to Saturn’s rings.

Metallic rutile oxides break the rules of cooling

Physicists have long puzzled over a strange contradiction inside a family of minerals called rutile oxides. These materials all share the same crystal structure—but while some of them, like titanium dioxide, are firmly insulating, others, like ruthenium dioxide, conduct electricity like a metal. So far, physicists have had little idea of why this happens.

In a new study published in Physical Review B, researchers led by Kaushik Sen at the Indian Institute of Technology Delhi traced the answer back to phonons: the tiny vibrations that ripple through a material’s atomic lattice.

Their discovery reveals that metallic rutile oxides develop a fundamentally different relationship between electrons and phonons as they cool—settling a long-running scientific dispute along the way.

How approaching sounds can warp your perception of time

Everyone’s perception of time is unique. It is a subjective experience shaped by factors such as age, emotions, memory and environmental contexts. And it may also be influenced by background noise, as scientists have demonstrated in a paper published in the journal Scientific Reports.

Previous research has shown that approaching noise can stretch our perception of time. But in this paper, researchers in Japan discovered that even when people were concentrating on a different sound, moving sounds in the background still changed their sense of time.

Quantum computers model nine fusion fuel material configurations for first time

A team of scientists from Oak Ridge National Laboratory, Cleveland Clinic and IBM has calculated nine molecular configurations of a promising material to produce fuel for fusion energy—the first known instance of such computations on quantum computers.

Such calculations, demonstrated in a new paper published on the arXiv preprint server, are computationally challenging for classical computers to scale when working alone. They are a fundamental step toward optimizing the production and extraction of tritium—an extremely rare material in nature that is necessary to produce fusion energy with most of the proposed machines. Ensuring adequate supplies of tritium has long been a barrier to realizing the promise of clean, abundant energy from fusion power plants, and solving this issue is a key objective of the U.S. Department of Energy’s Genesis Mission.

Quantum computers are well-suited to computing the atomic-level chemistry of a liquid salt that contains fluorine, lithium and beryllium (FLiBe), one of the leading candidate materials for extracting tritium fuel in fusion reactors. To compute different configurations of clusters of FLiBe, the team used the same quantum-centric supercomputing techniques now being applied to 12,635-atom protein simulations with Cleveland Clinic. These methods can calculate the quantum behavior of electrons in complex materials, complementing and enhancing the capabilities of classical supercomputers and algorithms.

Magnetic octupole model captures domain-wall motion in noncollinear antiferromagnets

Researchers from The Grainger College of Engineering at the University of Illinois Urbana-Champaign have developed the first magnetic multipole-based micromagnetic model for antiferromagnets. Published in Applied Physics Reviews, their generalized framework provides a theoretical and computational foundation for designing future spintronic devices made with antiferromagnetic materials.

Unlike traditional electronics, which rely on an electron’s charge, spin electronics harnesses an electron’s magnetic orientation (spin). In recent years, materials science researchers have identified antiferromagnets as a promising material for future spintronic devices because of their ultrafast spin dynamics and stability under external magnetic fields.

But before these materials can be implemented in practical devices, researchers need robust models that decipher their complex, nonuniform movements. Although micromagnetic simulations have been widely used to study spin dynamics in ferromagnets, a comparable framework had yet to be fully established for antiferromagnets, whose spin structure is more difficult to control. However, some types of antiferromagnets—such as noncollinear antiferromagnets—have a unique rotating structure that is more easily manipulated.

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