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Comment by Dr. Krishna Kumari Challa 7 hours ago

The research team also says the evidence suggests yawning is a way for the body to regulate the temperature in and around the brain.

In humans, the brain tissue can be up to 1°C warmer than the rest of the body, and venous blood leaving the brain is typically about 0.2–0.3°C warmer than the arterial blood entering it.
So when someone yawns, we can now see an increase in the cooler arterial blood flow into the skull, compensating for the coupled outflow of CSF and venous blood, and therefore we can surmise there may be a thermoregulatory process happening there.

"We could speculate that perhaps yawning is a way that the brain helps to cool itself down, but again we would need to do more research to state that with certainty.

"We do know that a hot brain is not a good thing because there is a risk of cell damage, seizures and cerebral swelling. And there is actually a very narrow band temperature-wise where the brain is steady and balanced, what is known as homeostasis.

"That's likely the reason why there are so many mechanisms—such as blood flow and sweating—that help regulate temperatures in the brain.

"We don't fully know what the level of contribution yawning may play in that, but this research opens up some interesting avenues for further investigation in that area as well."
The researchers also say they have identified for the first time that people appear to have a unique signature to their individual yawn, which can be identified by the complex way their tongue moves during the action.

Another interesting thing they found is that each person yawns in a unique way—so the tongue motion during the yawn is different between people, but very consistent for each person.
And it's not a simple motion. It's a very complex movement of the tongue during a yawn. It's almost like a fingerprint, so you could possibly identify someone just based on how they yawn.

Adam D. Martinac et al, Biomechanics of contagious yawning: Insights into cranio-cervical fluid dynamics and kinematic consistency, Respiratory Physiology & Neurobiology (2026). DOI: 10.1016/j.resp.2026.104575

Part 2

Comment by Dr. Krishna Kumari Challa 7 hours ago

A good yawn might do more than you think, say researchers

A simple yawn may feel like the most ordinary of human acts—a reflex triggered by tiredness, boredom, or seeing someone else's mouth stretch wide.

Yawning induces simultaneous outflow of cerebrospinal fluid and venous blood from the skull, a pattern distinct from deep breathing, which causes CSF inflow. This fluid movement may contribute to brain waste clearance and thermoregulation, suggesting a physiological role for yawning beyond social or behavioural triggers. Individual tongue motion during yawning is unique and consistent, resembling a biometric signature.

Now, a new imaging study suggests that yawning may play a subtle but intriguing role in moving fluids in and out of the brain. Although the researchers acknowledge the idea is speculative, they say their work introduces an interesting avenue for understanding the physiological functions of yawning.

Using real-time MRI scans, the team was able to see what happens inside the head and neck when people yawn, and compare it to the effect of normal and deep breathing.

The results, based on a small-scale group of 22 participants and published in Respiratory Physiology & Neurobiology, showed that yawning triggered a specific maneuver in which cerebrospinal fluid (CSF) and venous blood moved out of the skull together, whereas during deep breathing cerebrospinal fluid flowed into the skull.
Cerebrospinal fluid is a clear liquid that surrounds the brain and spinal cord, filling the space around them like water around a floating object. It is important because it cushions and protects the brain and spinal cord from injury and also helps carry nutrients in and waste products out.

The fact that CSF and venous blood flows away from the skull during yawning, but CSF flows in the opposite direction when deep breathing, was a big surprise to the researchers.

They observed that yawning is a body movement that can influence the flow of fluids around the brain.
There has been speculation that yawning can help clear waste from the brain, but so far there has not been solid proof.

This new research suggests that yawning can play a role in cleaning brain fluid, which would most likely happen close to bedtime.
This finding could be important for further studies into neurodegenerative diseases such as Alzheimer's, Parkinson's and dementia—all of which have been potentially linked to the build-up of waste products in and around the brain that can be a result of impaired CSF flows.
Part 1

Comment by Dr. Krishna Kumari Challa 7 hours ago

No brain required: This is how the single-celled Stentor learns
Stentor coeruleus, a single-celled organism lacking a nervous system, exhibits habituation by reducing its contraction response to repeated stimuli. This learning process relies on calcium influx and CaMKII-mediated protein modification rather than new protein synthesis. The acquired response can be inherited by daughter cells, indicating a non-neuronal molecular basis for memory storage.
Scientists have known for more than a century that a single-celled organism with no nerve cells—much less a brain—can behave in ways that resemble learning.
Now, scientists can explain how this simple organism, called Stentor coeruleus, learns: It uses molecular machinery that resembles what neurons have in the human brain. The results suggest that learning may be a fundamental feature of life.

In findings published in Current Biology, the researchers used modern neuroscience tools to study the pond-dwelling "Stentor," which is shaped like a trumpet and is large enough to be seen with the naked eye. These organisms contract when perturbed but stop after repeated jolts—a form of learning called habituation.
These single cells can perform behaviours that are normally associated with cognition and brains.
The results suggest that Stentors reacted to the jolts by allowing calcium to flow into their cells, which triggered an enzyme called CaMKII to add chemical tags to certain proteins. With each jolt, the Stentors became less likely to respond—suggesting the chemical tags had changed how the organisms sensed the jolts. The Stentors also passed this knowledge to their daughter cells when they divided.
Scientists are still trying to understand how Stentors store this knowledge, but it may involve mechanoreceptors, which respond to touch. Animal neurons do something similar using CaMKII to change the sensitivity of receptors on their surface. It's a tantalizing clue that learning may rely on molecular systems that existed long before the evolution of brains.

Deepa H. Rajan et al, Molecular pathways for learning in the single-cell Stentor coeruleus, Current Biology (2026). DOI: 10.1016/j.cub.2026.03.080

Comment by Dr. Krishna Kumari Challa 9 hours ago

A routine virus can slow breast cancer spread to the lungs, offering hidden protective power

Respiratory syncytial virus (RSV), mostly infects the lungs, nose, throat, and respiratory tract, and can cause illness ranging from mild cold and fever-like symptoms to severe pneumonia and bronchitis. A recent study has found that having a respiratory infection can act as a shield against the spread of cancer cells.
A natural antiviral chemical called type I interferons is produced by our body as one of the earliest responders in the fight against RSV infections. These molecules can also help prevent breast cancer from spreading to the lungs by changing the lung environment in a way that makes it difficult for cancer cells to survive or thrive. The findings are published in PNAS.

Ana Farias et al, Type I interferons induced upon respiratory viral infection impair lung metastatic initiation, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2412919123

Comment by Dr. Krishna Kumari Challa 9 hours ago

In their latest study, Vikram and Galitski expanded their theory further with insights from mathematician Laura Shou. Through their analysis, the trio concluded a clear relationship between the final entropy, the initial temperature, and the time taken to scramble a given number of units of quantum information.
They show that this kind of exact entropy- and temperature-dependent speed limit exists in every quantum system, where the previous expectation was that such speed limits only exist for systems in which each interaction only involves a few particles talking to each other.
With a deeper understanding of this speed limit, theorists could be far better placed to understand the emergence of thermal behavior in large-scale quantum systems, including emerging architectures for quantum computing and information processing. Even further, the result could be used to explore concepts from the origins of some forms of chaos, to the possibility of practical technologies for quantum teleportation, alongside more concrete theories of black hole radiation.

Amit Vikram et al, Proof of a Universal Speed Limit on Fast Scrambling in Quantum Systems, Physical Review Letters (2026). DOI: 10.1103/y9z4-v641. On arXiv: DOI: 10.48550/arxiv.2404.15403

Part 2

Comment by Dr. Krishna Kumari Challa 9 hours ago

Physicists reveal universal speed limit on quantum information scrambling

Theoretical physicists have discovered a "speed limit" on the time taken for quantum information to spread through larger systems. Publishing their results in Physical Review Letters, they have proved for the first time that this minimum time is closely linked with a system's entropy and temperature, perhaps paving the way for a deeper understanding of quantum information across a wide range of physical settings.

In 1974, Stephen Hawking proposed for the first time that black holes aren't entirely black. As well as emitting thermal radiation (now known as "Hawking radiation"), they also exhibit thermodynamic properties including temperature and an entropy proportional to their surface area.
Since entropy is a measure of the information carried by a system, this means a black hole's surface effectively stores a finite number of "qubits": the quantum equivalent of classical bits, each capable of storing quantum information as a superposition of two states simultaneously. In this way, the black hole's temperature as described by Hawking governs how these qubits interact and evolve over time.

In 2008, theoretical physicists Yasuhiro Sekino and Leonard Susskind took this idea a step beyond the abstract black hole picture. In the duo's conjecture, "systems of qubits at a certain temperature may take a minimum amount of time to share information with each other, which depends on the number of qubits and the temperature". This sharing of information is called 'scrambling,' and it effectively 'spreads' the information in each particle across the full system.

In the years since Sekino and Susskind's conjecture, theorists have studied the scrambling of quantum information in extensive detail. But one aspect of the concept that eluded mathematically exact predictions was the idea of a temperature-dependent "speed limit" on the scrambling process itself.
In 2024, Vikram and Victor Galitski at the University of Maryland revisited the idea through the lens of the energy-time uncertainty principle: a cornerstone of quantum theory which posits the more that is known about the energy of a quantum system, the less is known about the minimum time needed for it to change into a distinguishably different state, and vice versa. As a result, there is a minimum time needed for quantum systems to change, imposed by their well-defined energy levels.
Part 1

Comment by Dr. Krishna Kumari Challa yesterday

Fruit and nuts fight non-alcoholic fatty liver disease

Eating fruit and nuts can help protect against non-alcoholic fatty liver disease (NAFLD)—but a popular fiber supplement can make the condition worse, new research has found. The paper, "Ellagic Acid Reduces Inulin's Adverse Effects: A Combined Approach to Enhance Therapeutic Potential in Non-alcoholic Steatohepatitis," was published in Molecular Nutrition and Food Research.

Caused by factors such as obesity, diabetes and high blood pressure, NAFLD become the most prevalent liver disease globally, affecting 38% of the population. And there is no way to treat it.

Scientists at ECU have been investigating dietary preventions and found that a certain compound found in some fruits and nuts, could stop and potentially reverse the damage caused by NAFLD.

They found that ellagic acid (EA), which is found in a variety of foods such as pomegranates, berries, grapes and walnuts, helped to protect the liver from disease.

Ellagic acid is a natural antioxidant known for its potential anti-inflammatory and anticancer properties and holds great promise in treating various chronic diseases.

The study, which was conducted on mice, also warns that a commonly used fiber supplement  readily available at pharmacies, health stores and online, could make NAFLD worse if taken on its own without EA.

Inulin is a type of soluble fiber often used as a prebiotic to improve gut health, but the research showed it led to an unexpected increase in body weight and blood glucose levels and worsened liver damage, possibly because of the imbalance of microbes in the gut associated with NASH.

This research reinforces the idea that diet matters—not just what we eat, but how different nutrients interact in the body.

Tharani Senavirathna et al, Ellagic Acid Reduces Inulin's Adverse Effects: A Combined Approach to Enhance Therapeutic Potential in Nonalcoholic Steatohepatitis, Molecular Nutrition & Food Research (2026). DOI: 10.1002/mnfr.70456

Comment by Dr. Krishna Kumari Challa yesterday

Light pollution alters food webs along riverbanks, finds study
Artificial light at night significantly disrupts energy and nutrient exchange between aquatic and terrestrial ecosystems along riverbanks, altering food web dynamics more than invasive species. Light pollution changes the diet composition of predatory spiders and increases predation by invasive crayfish, reducing insect emergence and impacting terrestrial predators. These effects highlight the underestimated ecological consequences of artificial lighting.

Collins Ogbeide et al, Artificial light at night and invasive signal crayfish alter aquatic‐terrestrial food webs, Functional Ecology (2026). DOI: 10.1111/1365-2435.70335

Comment by Dr. Krishna Kumari Challa yesterday

Urban birds fear women more than men!

An international team of researchers have made the surprising discovery that urban birds—such as great tits, house sparrows and blackbirds—flee sooner when approached by women compared to men. But they don't yet understand why. Conducted across five European countries, the study involved male and female participants (matched for height and clothing) walking in a straight line towards birds in urban parks and green spaces.

The researchers found that compared to women, men were able to get an average of one meter closer to birds before they fled (termed flight initiation distance). The results, published in the journal, People and Nature, were consistent across all five countries: Czechia, France, Germany, Poland and Spain.

This finding was also consistent across the 37 bird species studied, from species that typically flee early, like magpies, to species that flee late, like pigeons.

From the results, the researchers conclude that urban birds can recognize the sex of the humans approaching them. But what traits the birds are picking up on or why they are more fearful of women remain a mystery.

The researchers have a few hypotheses for what birds are detecting, such as pheromones, body shape or gait, but say these are speculative and that more research is needed.

Federico Morelli et al, Sex matters: European urban birds flee approaching women sooner than approaching men, People and Nature (2025). DOI: 10.1002/pan3.70226

Comment by Dr. Krishna Kumari Challa yesterday

Your 'recycled polyester' leggings are not as sustainable as you think
Most recycled polyester in fashion is made from PET drink bottles, not textile waste, diverting material from an effective bottle-to-bottle recycling system into a less recyclable form. Once converted to clothing, polyester is typically downcycled, with limited recycling options, leading to landfill or incineration. Recycled polyester garments may shed more microplastics than virgin polyester, increasing environmental pollution. The most sustainable use for PET bottles remains within closed-loop bottle recycling rather than conversion to textiles.

original article.

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