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Comment by Dr. Krishna Kumari Challa on January 9, 2025 at 9:13am

This unexpected behavior suggests fractional excitons could represent an entirely new class of particles with unique quantum properties.

This shows that excitons can exist in the fractional quantum Hall regime and that some of these excitons arise from the pairing of fractionally charged particles, creating fractional excitons that don't behave like bosons.

The existence of a new class of particles could one day help improve the way information is stored and manipulated at the quantum level, leading to faster and more reliable quantum computers, the team noted.

Naiyuan J. Zhang et al, Excitons in the fractional quantum Hall effect, Nature (2025). DOI: 10.1038/s41586-024-08274-3. www.nature.com/articles/s41586-024-08274-3

Part 2

Comment by Dr. Krishna Kumari Challa on January 9, 2025 at 9:12am

Discovery of new class of particles could take quantum mechanics one step further

Amid the many mysteries of quantum physics, subatomic particles don't always follow the rules of the physical world. They can exist in two places at once, pass through solid barriers and even communicate across vast distances instantaneously. These behaviors may seem impossible, but in the quantum realm, scientists are exploring an array of properties once thought impossible.

In a new study, physicists  have now observed a novel class of quantum particles called fractional excitons, which behave in unexpected ways and could significantly expand scientists' understanding of the quantum realm.

The findings point toward an entirely new class of quantum particles that carry no overall charge but follow unique quantum statistics.

The most exciting part is that this discovery unlocks a range of novel quantum phases of matter, presenting a new frontier for future research, deepening our understanding of fundamental physics, and even opening up new possibilities in quantum computation.

The research   was published in Nature on Wednesday, Jan. 8.

The team's discovery centers around a phenomenon known as the fractional quantum Hall effect, which builds on the classical Hall effect, where a magnetic field is applied to a material with an electric current to create a sideways voltage.

The quantum Hall effect, occurring at extremely low temperatures and high magnetic fields, shows that this sideways voltage increases in clear, separate jumps. In the fractional quantum Hall effect, these steps become even more peculiar, increasing by only fractional amounts—carrying a fraction of an electron's charge.

In their experiments, the researchers built a structure with two thin layers of graphene, a two-dimensional nanomaterial, separated by an insulating crystal of hexagonal boron nitride. This setup allowed them to carefully control the movement of electrical charges. It also allowed them to generate particles known as excitons, which are formed by combining an electron and the absence of an electron known as a hole.

They then exposed the system to incredibly strong magnetic fields that are millions of times stronger than Earth's. This helped the team observe the novel fractional excitons, which showed an unusual set of behaviours.

Fundamental particles typically fall into two categories. Bosons are particles that can share the same quantum state, meaning many of them can exist together without restrictions. Fermions, on the other hand, follow what's known as the Pauli exclusion principle, which says no two fermions can occupy the same quantum state.

The fractional excitons observed in the experiment, however, didn't fit cleanly into either category. While they had the fractional charges expected in the experiment, their behavior showed tendencies of both bosons and fermions, acting almost like a hybrid of the two. That made them more like anyons, a particle type that sits between fermions and bosons—yet the fractional excitons had unique properties that set them apart from anyons, as well.

Part 1

Comment by Dr. Krishna Kumari Challa on January 9, 2025 at 8:55am

Particles aren't just these fundamental things, they're also important in describing materials.
This is cross-disciplinary research that involves several areas of theoretical physics and mathematics.
Using advanced mathematics, such as Lie algebra, Hopf algebra and representation theory, as well as a pictorial method based on something known as tensor network diagrams to better handle equations, the researchers were able to perform abstract algebraic calculations to develop models of condensed matter systems where paraparticles emerge.

They showed that, unlike fermions or bosons, paraparticles behave in strange ways when they exchange their positions with the internal states of the particles transmuting during the process.
While they are groundbreaking on their own, these models are the first step toward a better understanding of many new physical phenomena that could occur in paraparticle systems. Further development of this theory could guide experiments that could detect paraparticles in the excitations of condensed matter systems.

Zhiyuan Wang et al, Particle exchange statistics beyond fermions and bosons, Nature (2025). DOI: 10.1038/s41586-024-08262-7

Part 2

Comment by Dr. Krishna Kumari Challa on January 9, 2025 at 8:52am

Mathematical methods point to possibility of particles long thought impossible

From the early days of quantum mechanics, scientists have thought that all particles can be categorized into one of two groups—bosons or fermions—based on their behaviour.

However, new research shows the possibility of particles that are neither bosons nor fermions. The study, published in Nature, mathematically demonstrates the potential existence of paraparticles that have long been thought impossible.

Quantum mechanics has long held that all observable particles are either fermions or bosons. These two types of particles are distinguished by how they behave when near other particles in a given quantum state. Bosons are able to congregate in unlimited numbers, whereas only one fermion can exist in a given state. This behaviour of fermions is referred to as the Pauli exclusion principle, which states that no more than two electrons, each with opposite spins, can occupy the same orbital in an atom.

In the 1930s and 1940s, researchers began trying to understand whether other types of particles could exist. A concrete quantum theory of such particles, known as paraparticles, was formulated in 1953 and extensively studied by the high energy physics community. However, by the 1970s, mathematical studies seemed to show that so-called paraparticles were actually just bosons or fermions in disguise. The one exception was the existence of anyons, an exotic type of particle that exists only in two dimensions.

However, the mathematical theories of the 1970s and beyond were based on assumptions that are not always true in physical systems. Using a solution to the Yang-Baxter equation, an equation useful for describing the interchange of particles, along with group theory and other mathematical tools,  researchers set to work to show that paraparticles could theoretically exist and be fully compatible with the known constraints of physics.

The researchers focused on excitations—which can be thought of as particles—in condensed matter systems such as magnets to provide a concrete example of how paraparticles can emerge in nature.

Part 1

Comment by Dr. Krishna Kumari Challa on January 8, 2025 at 11:11am

The prognosis of heat stroke varies according to patient factors, particularly extremes of age," explain the authors. "Classical heat stroke in elderly people carries a mortality rate of [more than] 50%, and this increases further with each additional organ dysfunction.

"Heat-related deaths spike during heat waves, as has been observed in multiple large international datasets. Deaths from heat stroke are expected to rise as global temperatures continue to increase," they add.

"Once heat stroke has occurred, the key determinate of outcome is how rapidly a patient is cooled, as the time spent with elevated core body temperature is correlated to the degree of cellular damage," they emphasize.

Severe heat stroke with multiorgan failure following collapse in a sauna, BMJ Case Reports (2025). DOI: 10.1136/bcr-2024-262069

Part 2

Comment by Dr. Krishna Kumari Challa on January 8, 2025 at 11:09am

Basking too long in a sauna without adequate hydration may risk heat stroke, doctors warn

Basking too long in a sauna may put bathers at risk of heat stroke, particularly if they haven't drunk enough water beforehand, warn doctors in the journal BMJ Case Reports, after treating a woman whose condition required admission to hospital.

Although relatively rare, heat stroke can be life-threatening, even in the absence of various underlying risk factors, such as heart, lung, or neurological disease, and heavy drinking or taking a cocktail of prescription meds, they point out.

Heat stroke is defined as a sharp increase in core body temperature above 40°C that is associated with acutely impaired brain function, and 'non-exertional' heat stroke results from prolonged exposure to high environmental temperatures, explain the authors.

They treated a woman in her early 70s who had been found unconscious in her local gym's sauna, where she had been doing stretching exercises for around 45 minutes. Her core body temperature was 42°C—normal temperature is 36.4°C—her blood pressure was extremely low, and her heart rate was extremely high. She had a seizure after her arrival in emergency care.

She had previously been diagnosed with type 1 diabetes and an underactive thyroid, but she wasn't a smoker or heavy drinker, and was a regular gym goer, so had few risk factors, point out the authors.

She was rapidly cooled with wet towels and a fan and given intravenous fluids and blood products to stabilize her.

Blood tests revealed malfunctioning kidneys and liver, evidence of a minor heart attack, and muscle tissue breakdown (rhabdomyolysis).

She regained consciousness within two hours of reaching normal core temperature but was confused and drowsy for two days. By day three, this had resolved and she had no further seizures during her inpatient stay, which lasted 12 days.

After 26 days, she had more or less fully recovered, except for some mild fatigue and mild liver function disturbance.

This is just one case report after prolonged sauna use, and as far as the authors are aware, only nine other similar cases have been reported. But three of those people died as a result.

Part 1

Comment by Dr. Krishna Kumari Challa on January 8, 2025 at 10:12am

Researchers Explore Touchless Fingerprints: The Next Step in Biometric Technology

Fingerprints have always been one of the most reliable ways to identify a person. 

Traditionally, fingerprints are captured by pressing your finger against a surface, like when you unlock your phone or when using biometric scanners at work. However, new research is exploring a touch-free way to capture fingerprints aiming to make this process cleaner, easier, and more accurate. A collaboration between researchers is looking to use a photograph of your finger to capture fingerprints.

A fingerprint is composed of unique patterns of ridges and valleys on the skin of your fingers. Features called "minutiae," where ridges end, or split, are unique to an individual and play a crucial role in distinguishing one fingerprint from another. In this study, the scientists devised a method that begins with capturing a picture of your finger instead of pressing it against a scanner. They then use a range of image processing techniques to highlight and enhance the intricate details of your fingerprint in the photo.

A method called Adaptive Thresholding helps adjust the brightness levels to make the fingerprint patterns more distinct. Next, a "Gabor Filter," which sharpens the textures, emphasizing those all-important ridges and valleys, is applied. Once the minutiae are clearly visible, they use something called a K-means clustering algorithm to remove the background from the image, much like focusing a camera lens to blur out everything except the main subject – your fingerprint. Once the image is processed, it undergoes a thinning process to make the fingerprint one pixel wide. This skeletonized version of the fingerprint is then used to extract minutiae.

Additionally, the researchers used an innovative combination of machine learning, specifically a kind of artificial intelligence called a "Siamese network," with traditional techniques. The Siamese network aids in learning patterns by comparing more than one fingerprint image and recognizing similar features, making the system very accurate. Using this combination method, the system achieves impressive accuracy, with the error rate dropping as low as 2.5% or 3.76% depending on the datasets used for testing.

While the current research is promising, there are still areas that need further exploration. Researchers are interested in testing different types of wavelets (a mathematical function used to analyze the details at different frequencies) that could potentially enhance the process and results. Additionally, they aim to develop even more advanced techniques for fusing all the gathered information, making the fingerprint identification process even more robust.

This touchless method has some immediate perks. For one, it’s more hygienic since you don’t have to physically touch a scanner. Imagine not having to worry about transferring germs and viruses, as experienced during the COVID-19 pandemic. Moreover, it overcomes problems like sensor wear and tear, which can happen very quickly when a device gets pressed repeatedly. In the future, these advancements could even allow for systems that recognize other biometric data like palm prints or face characteristics, integrating them into a singular system for even more secure identification.

https://ieeexplore.ieee.org/document/10759693

Comment by Dr. Krishna Kumari Challa on January 7, 2025 at 12:04pm

The research team decided to focus on how PFAS affects the gene expression of neuronal-like cells, as well as how PFAS affects lipids, which are molecules that help make up the cell membrane, among other important functions. Exposure to different PFAS for 24 hours resulted in modest but distinct changes in lipids, and over 700 genes expressing differently.

Of the six types of PFAS tested, perfluorooctanoic acid (PFOA)—once commonly used in nonstick pans and recently deemed hazardous by the EPA—was by far the most impactful. Despite its small uptake, PFOA altered the expression of almost 600 genes—no other compound altered more than 147. Specifically, PFOA decreased the expression of genes involved in synaptic growth and neural function.

Altogether, the six compounds caused changes in biological pathways involved in hypoxia signaling, oxidative stress, protein synthesis and amino acid metabolism, all of which are crucial for neuronal function and development.

 Logan Running et al, Investigating the Mechanism of Neurotoxic Effects of PFAS in Differentiated Neuronal Cells through Transcriptomics and Lipidomics Analysis, ACS Chemical Neuroscience (2024). DOI: 10.1021/acschemneuro.4c00652

Part 2

Comment by Dr. Krishna Kumari Challa on January 7, 2025 at 12:02pm

Scientists identify 11 genes affected by PFAS, shedding light on neurotoxicity

Per- and polyfluorinated alkyl substances (PFAS) earn their "forever chemical" moniker by persisting in water, soil and even the human brain. This unique ability to cross the blood-brain barrier and accumulate in brain tissue makes PFAS particularly concerning, but the underlying mechanism of their neurotoxicity must be studied further.

To that end, a new study by  researchers has identified 11 genes that may hold the key to understanding the brain's response to these pervasive chemicals commonly found in everyday items. The paper is published in the journal ACS Chemical Neuroscience.

These genes, some involved in processes vital for neuronal health, were found to be consistently affected by PFAS exposure, either expressing more or less, regardless of the type of PFAS compounds tested. For example, all compounds caused a gene key for neuronal cell survival to express less, and another gene linked to neuronal cell death to express more.

Still, the study found that hundreds more genes whose expression changed in different directions based on the compound tested. Plus, there was no correlation between the level at which PFAS accumulates in a cell and the extent to which it causes differential gene expression.

Taken together, this suggests that distinct molecular structures within each type of PFAS drive changes in gene expression.

PFAS aren't immediately toxic. We're exposed to them practically every day, including through drinking water and food packaging, and don't notice.

Therefore, researchers need to find points of assessment further upstream in the cellular process than just whether a cell lives or dies.

Part 1

Comment by Dr. Krishna Kumari Challa on January 7, 2025 at 10:34am

Three years of solar fireworks

This video combines ultraviolet images of the sun's outer atmosphere (the corona, yellow) taken by Solar Orbiter's Extreme Ultraviolet Imager (EUI) instrument, with the size and locations of solar flares (blue circles) as recorded by the Spectrometer/Telescope for Imaging X-rays (STIX) instrument. The accompanying audio is a sonification based on the detected flares and the spacecraft's distance to the sun.

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