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Comment by Dr. Krishna Kumari Challa yesterday

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 yesterday

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 on Wednesday

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 on Wednesday

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 on Wednesday

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 on Wednesday

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.

Comment by Dr. Krishna Kumari Challa on Wednesday

Invisible fertility crisis: Chemicals and climate change threaten reproduction across species

The rise in infertility is not limited to humans, as environmental stressors are quietly undermining the reproductive potential of different forms of life. A recent review published in npj Emerging Contaminants investigated how today's environmental challenges are shaping the reproductive capacity of both humans and animals.

From the analysis emerged two major forces—synthetic chemicals and warming climate—that are not acting in isolation but as a unit, placing growing pressure on fertility and fecundity (biological capacity of an organism to reproduce) across a wide spectrum of species.

The effects range from skewed sex ratios and poorer egg and sperm quality to developmental abnormalities and falling population numbers. The impact is not limited to a single generation; it carries its mark into future generations and tends to worsen when chemical exposure and climatic changes hit together.

Susanne M. Brander et al, Impacts of environmental stressors on fertility and fecundity across taxa, with implications for planetary health, npj Emerging Contaminants (2026). DOI: 10.1038/s44454-026-00032-6

Comment by Dr. Krishna Kumari Challa on Wednesday

The researchers estimate that any cognitive differences would be very small at only 0.14 standard deviations. This is based on the weak links between brain anatomy and cognitive performance seen in modern humans. That suggests that the mental abilities of the two groups living in Eurasia were similar on average.

Therefore, according to the team, the range of intelligence in Neanderthals and in humans would have overlapped heavily. So some Neanderthals could have been more capable than some early humans.

"If cognitive differences between modern human populations are not considered significant, Neanderthal differences from their contemporaries should not be either," said the researchers.

In other words, we shouldn't treat Neanderthal differences as especially meaningful if similar differences among humans aren't.

P. Thomas Schoenemann et al, Neanderthal brain and cognition reconsidered, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2426638123

Part 2

Comment by Dr. Krishna Kumari Challa on Wednesday

Neanderthal brains were not very different from human brains!

We appear to have more in common with our Neanderthal cousins than outward appearances would suggest. New research published in the journal Proceedings of the National Academy of Sciences suggests that the differences between Neanderthal brains and the brains of early modern humans (Homo sapiens) were no greater than the differences we see between various groups of people living today. The findings could challenge the long-held theory about why Neanderthals disappeared around 40,000 years ago.

The popular narrative suggests that Neanderthals were not as smart as the early humans who colonized their territory in Eurasia and ultimately replaced them.

The stock image of Neanderthals as brutish, cognitively inferior cavemen largely stems from differences in the shape of their skulls. Because theirs were more elongated and less round than ours, scientists assumed their brain organization was less advanced. Consequently, it was thought they lacked the memory and language skills that would have been necessary to compete with us. But this may not be correct.
A team of scientists took brain scans (MRIs) from two large modern groups of people: one made up of ethnic Han Chinese individuals and the other composed of Americans with European ancestry. They measured the volumes of 13 different brain regions in these groups and compared them with previously reported differences between Neanderthals and early modern humans who lived alongside them. These measurements were taken from endocasts, 3D models of the inside of Neanderthal skulls used to estimate brain shape and size.

They found that in 9 of the 13 brain regions, the volume differences between the modern Chinese and modern US samples were larger than those between Neanderthals and early humans. "The differences between modern human and Neanderthal brains, as estimated from endocranial reconstructions, do not meaningfully exceed those among different modern human populations," explained the study authors in their paper.

Part 1

Comment by Dr. Krishna Kumari Challa on Wednesday

Microplastics turn up in nearly every human brain sample, including healthy tissue

Tiny micro- and nanoplastic fragments seem to be turning up everywhere, including one of the most well-protected parts of the human body—the brain. In a recent study conducted by researchers, they found microplastics and nanoplastics (MNPs) in nearly all the brain samples they tested, both healthy and diseased human brains.

As per the findings published in Nature Health, the microplastic levels were the highest recorded in the study, reaching 129 micrograms per gram in tumor-affected brain tissue. The healthy brain and spinal cord tissue had considerably lower levels, with a median of 50.3 micrograms per gram. 

Studies have found that microplastics can enter the human body through breathing, eating, and skin contact. The brain is protected by an exceptionally selective filter called the blood-brain barrier, designed to keep harmful substances out of our most vital organ. Yet previous studies have found that microplastics can somehow bypass this defense and enter the brain. This is particularly concerning because very little is known about what these foreign particles do once inside, where they go and settle, or what concentrations they can reach.

The study authors realized that MNPs were present in almost all samples: 99.4% of diseased tissue samples and 100% of healthy tissue samples. Nanoplastics, which are smaller in size, were more abundant than microplastics. The team was even able to identify the type of plastic the tiny bits came from: PET, often used to make beverage bottles; polyethylene, commonly used in plastic bags; polyamide that makes up textiles like nylon and PVC found in plumbing and industrial equipment.

In diseased brains, levels were not uniform across the tissue, with higher concentrations near tumors, possibly due to weakened natural protection. They detected these particles in operating room environments, raising the possibility of exposure during medical procedures.
Their analysis also found that the larger the surface area of microplastics, the faster the tumor cell growth. While this doesn't mean microplastics cause cancer, it does raise questions about the role MNPS may play in how quickly the disease progresses, an area the researchers noted requires further exploration.

Tackling MNP pollution calls for joint action from policymakers, manufacturers, and consumers. Findings from this study, along with future research, can strengthen public awareness and drive demand for change, helping to push policies grounded in evidence.

Runting Li et al, Microplastics and nanoplastics in brain tumours and the healthy human brain, Nature Health (2026). DOI: 10.1038/s44360-026-00091-4

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