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Comment by Dr. Krishna Kumari Challa on Saturday

Cows v plants: Which milk delivers the best health benefits?

New research has shed light on the growing debate between cow's milk and plant-based alternatives. Results of the study, published in the journal Critical Reviews in Food Science and Nutrition, suggest that cow's milk has the edge over plant-based alternatives when it comes to bone strength and nutrient absorption.
Milk is more than just calcium, protein and fat—it's a complex whole food, and how its nutrients are packaged together is more important than initially thought.
Milk contains more than 100 nutrients and bioactive substances, arranged in a unique physical structure.

This structure affects how nutrients are digested and absorbed, how blood sugar responds after a meal, how fats affect cholesterol, and how the gut microbiome responds.

It's the way all the parts of milk interact that appears to link to many of its health benefits.
The findings suggest that while plant-based drinks are increasing in popularity, they do not consistently match the nutritional quality or health outcomes associated with dairy milk.

Researchers found that regular milk consumption is linked to stronger bones and a lower risk of fractures, with some evidence showing up to a 43% reduction among people who drink one to two cups a day.

In contrast, calcium supplements, often used as a replacement, showed mixed results and were, in some cases, associated with a higher risk of heart disease, particularly among older women.

The difference, researchers said, comes down to the way nutrients are delivered.

Milk provides a natural package of nutrients that work together. Calcium in milk is combined with protein, phosphorus and other components that help the body absorb and use it efficiently. This is something that plant-based drinks and supplements cannot fully replicate.
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Comment by Dr. Krishna Kumari Challa on Saturday

Flu infection may weaken tuberculosis defenses by disrupting key immune pathways
Controlled human influenza infection reduced blood immune control of Mycobacterium tuberculosis, with post‑influenza samples showing increased mycobacterial growth. This loss of control was linked to disruption of type I interferon signalling pathways. Seasonal influenza vaccination may indirectly enhance TB control in high‑burden settings.

Claire M. Broderick et al, Influenza coinfection inhibits control of mycobacterial infection in a human challenge model, Nature Communications (2026). DOI: 10.1038/s41467-026-72363-2

Comment by Dr. Krishna Kumari Challa on Saturday

Why chickens come in so many colors, and what one gene reveals about evolution

From snow white and jet black to golden brown, domestic chickens display a wider range of plumage colors than almost any other livestock species. A new international study explains why: A single gene is capable of producing this full spectrum. The study provides an example of how genetic diversity and visible traits can emerge within a short evolutionary period. The findings have now been published in the Proceedings of the National Academy of Sciences.

Researchers show how the remarkable colour diversity of domestic chickens arises at the molecular level. The study focused on the melanocortin-1 receptor (MC1R), a protein molecule that controls colour formation in the skin cells of vertebrates.

The gene that encodes this pigmentation receptor has undergone an unusually high degree of change in domestic chickens since their domestication. The research team identified 18 different variants of the gene—a level of diversity not found in wild birds. The Researchers show that the accumulation and recombination of mutations within a single gene has given rise to numerous new variants, with directly visible effects on the birds' appearance.
MC1R functions like a molecular switch: Depending on how active it is, a cell produces either more dark pigment or more light pigment. Using cell cultures, the researchers demonstrated that individual gene mutations can either increase or decrease the activity of this switch. When several mutations occur together, they can reinforce or counteract one another, creating color patterns that none of the individual changes could produce on their own.

Domestic chickens exhibit exceptional plumage diversity due to extensive variation in a single gene, MC1R, which encodes a key pigmentation receptor. Eighteen MC1R variants, generated by accumulated and recombined mutations, modulate receptor activity to shift dark/light pigment production and create complex colour patterns. This illustrates rapid evolution of visible traits over a short domestication timescale.

Cheng Ma et al, Ultrarapid MC1R protein and associated plumage color evolution in the domestic chicken, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2605288123

Comment by Dr. Krishna Kumari Challa on Saturday

Why cells started sticking together could help explain how animals first evolved

A recent study published in Nature may help us understand the beginnings of animal evolution billions of years ago.
Animal bodies are made up of trillions of cells that stick together and cooperate. Billions of years ago—before animals evolved—every living thing on Earth was a single-celled organism. Eventually, some of these cells began sticking together, working together and then reproducing as multicellular organisms. Some of these early multicellular organisms evolved into present-day plants or fungi, while others evolved into animals.
The researchers found that after feeding a specific bacterium to a unicellular relative of animals, the single cells began to stick to one another, revealing a possible way our ancestors began to evolve into animals billions of years ago.
Feeding a specific bacterium to the unicellular holozoan Ministeria vibrans induced stable cell aggregation, improving feeding efficiency and potential protection of resources. During this transition, M. vibrans expressed adhesion and signalling proteins homologous to those in animals, indicating that key molecular machinery for multicellularity predated animal origins.
M. vibrans survives by eating bacteria. Researchers rigorously tested different bacterial foods until they found one that encouraged single M. vibrans cells to stick together and become multicellular. The bacteria got trapped between the aggregating cells, meaning it was more efficient for M. vibrans to collect food by sticking together rather than remaining single-celled organisms. Further, by sticking together, the cells might be able to protect their food from other organisms.

Sticking together also provides opportunities for cells to exchange genes via mating, which may produce new genetic combinations that enable adaptation to new environments.
The researchers observed that when M. vibrans evolved from unicellular to multicellular, it produced the same proteins that many animal cells use to stick together. The multicellular form of M. vibrans also produced many proteins that animal cells use to communicate and coordinate behaviour. The team concluded that the unicellular organisms that evolved into animals also likely used these proteins to form multicellular bodies and cooperate.

Ruibao Li et al, A unicellular relative links aggregative multicellularity to animal origins, Nature (2026). DOI: 10.1038/s41586-026-10748-5

Comment by Dr. Krishna Kumari Challa on Saturday

Trees may store less carbon than expected in the future

It's normal to think that if a tree is photosynthesizing, it's also growing. But that's not necessarily so—and a new study of oak trees, published in the journal Science Advances, found that even as they photosynthesize late into the year, their growth stops by midsummer.
Much of the long-term carbon storage that forests provide depends on trees converting the carbon they absorb through photosynthesis into new wood. Many researchers have predicted that rising atmospheric carbon dioxide (CO2) levels will enhance photosynthesis and stimulate tree growth, putting some of that planet-warming carbon into long-term storage inside wood.

However, the observed decoupling of photosynthesis from growth suggests that increased carbon uptake does not necessarily translate into greater wood production. Instead, some of the absorbed carbon may be used to produce foliage or used in short-lived metabolic processes rather than being locked away long term, reducing the amount of carbon stored in forests compared with previous expectations.

The finding has climate implications.

Decoupled carbon assimilation and growth responses to aridity in temperate deciduous oaks, Science Advances (2026). DOI: 10.1126/sciadv.ady7139. www.science.org/doi/10.1126/sciadv.ady7139

Comment by Dr. Krishna Kumari Challa on Saturday

Human understanding of AI can't keep up with its advancement, researchers say

In a recent editorial published in Science, Microsoft's chief scientific officer, Eric Horvitz, and researcher Robert West from the School of Computer and Communication Sciences at EPFL in Switzerland issue a stark warning about AI. They say the advancement of AI systems rapidly being woven into our everyday lives is beginning to outpace our understanding of them. At the same time, AI's understanding of human behaviour is expanding.
The authors of the editorial point to three main areas where AI is becoming less understandable. The first is the rise of AI-directed AI design, in which AI is increasingly designing and improving other AI systems. The authors say the cycles involved in this process outpace human understanding and occur in "high-dimensional spaces that resist intuition." They say that while the performance of the systems may improve, humans struggle to understand why or how.

The second trend is the interactions between AI agents. Now at scale, these agents are forming multi-agent ecosystems whose internal communication may drift away from human language and reasoning. As newly formed AI interactions and communications become more complex, humans become less capable of interpreting them.

Lastly, adaptive AI agents are quickly learning more about human behavior, creating a one-sided situation in which AI understands us better than we understand it. As they parse untold amounts of data from interactions with humans and data showing how humans interact with each other, AI systems begin to understand us better than we understand ourselves and certainly better than we understand them.

The authors write, "Through sustained interaction, they can build increasingly detailed models of human behaviour and psychology, capturing not only preferences but also latent drivers such as fear, uncertainty, and the need for social belonging."
So what happens when AI systems reach a point beyond human understanding? The authors warn that without strong countermeasures, the resulting opacity could lock in AI systems that are powerful but effectively ungovernable by humans. They say that once this happens, recovering human agency may not be possible. This imbalance of understanding could affect personal autonomy, democratic decision-making and trust in institutions.

As AI's understanding of humans deepens, the authors warn that one outcome is that the output of AI systems may increasingly reflect human expectations instead of reality, essentially telling humans only what they want to hear. Without understanding, we won't know that this is happening. In addition, human curiosity, skepticism and scrutiny of AI may simply wane.
More subtle is the possibility that we will gradually lose interest in understanding and guiding AI. As AI systems become deeply embedded in human environments, they may respond to preferences but also shape them. Systems optimized for engagement or approval may reduce friction and discourage scrutiny. Over time, curiosity and skepticism may erode, leading to neglect and acceptance," the authors write.
Some of these risks may be speculative, but they are based on extrapolating current trends into the future.

Eric Horvitz et al, A narrowing window to understand AI, Science (2026). DOI: 10.1126/science.aei3167

Comment by Dr. Krishna Kumari Challa on Saturday

A cornerstone of Milky Way history may need rewriting with evidence of multiple ancient mergers

Astronomers may have uncovered new details about one of the Milky Way's most important ancient collisions. Using data from the Dark Energy Spectroscopic Instrument (DESI) and a new clustering algorithm, researchers have found evidence suggesting the famous Gaia-Sausage/Enceladus structure (GSE) has a far more complicated origin than previously thought.

Our galaxy formed through a series of mergers and accretion events over billions of years. These collisions left behind stellar streams and substructures (groups of stars) that still carry the chemical and dynamical fingerprints of the events that created them.

The GSE is the most prominent of these, long considered the remnant of the Milky Way's last major merger and thought to have fundamentally shaped our galaxy's inner halo. Previous studies placed this event between 10 billion and 13 billion years ago, though more recent work has suggested it may have occurred within the past few billion years.

In this new study, researchers analyzed 86,945 stars using DESI data, applying a new computational search tool called GS³ Hunter to sort stars into groups based on their properties. The tool identified 17 separate streams and substructures in total—including the previously known Sequoia stream and more than a dozen newly discovered ones. Four of these fell within the GSE region, designated GSE-GSH1 through GSE-GSH4, and it is these four that hold the most important clues to our galaxy's complex history.

Each substructure carries a unique chemical signature. Elements like magnesium, calcium and titanium follow similar patterns across all four groups, with only minor differences.

Researchers say this suggests these stars all formed from chemically similar material. On the other hand, aluminum and carbon-to-nitrogen ratios vary notably between the groups, with some showing signatures of rapid, intense early star formation and others pointing to slower star formation over a long period.

One substructure, GSE-GSH2, stands out in particular. It shows multi-peaked chemical patterns that suggest a messier, more episodic formation compared with the other three.

The stars' orbits further support the picture of a chaotic past. All four groups travel in the highly elongated paths typical of merger debris. This occurs when stars are thrown into stretched-out orbits after their original galaxy was torn apart. But each group sits in a slightly different region of orbital space, which the researchers explain as being "consistent with material being stripped at different phases of the progenitor's disruption, or from multiple progenitors.

" Perhaps the most striking clue comes from stellar ages. The four populations span roughly 7 billion to 12 billion years—a 5-billion-year spread. This is inconsistent with a single, short-lived merger event, which would have produced stars of similar ages. The wide age spread instead points to multiple separate accretion events depositing debris across billions of years of the Milky Way's early history.

The evidence points to several events in which different galaxies were absorbed by the Milky Way, forming the GSE. "These findings point to GSE as the composite outcome of multiple accretion episodes, potentially involving progenitors with different star formation histories and enrichment timescales," the team writes in the paper.

Hai-Feng Wang et al, A More Complex Than Expected Formation History of the Milky Way's Last Major Merger, arXiv (2026). DOI: 10.48550/arxiv.2606.04462

Comment by Dr. Krishna Kumari Challa on Saturday

A higher-dose flu shot could spare millions of older adults a hospital stay

Influenza is a seasonal condition that causes coughing, sneezing, mild fever and aches in most cases. However, it can sometimes take a serious turn, leading to hospitalization, especially for young children, adults over 65 and pregnant people. A recent study published in JAMA Network Open examined whether the high-dose inactivated influenza vaccine (HD-IIV), which contains four times as much antigen as the standard dose, offers superior protection against hospitalization and death.

Researchers analyzed data from eight large-scale clinical trials involving more than 600,000 participants that compared a high-dose flu shot with the standard flu shot in older adults.

The high-dose vaccine provided substantially greater protection, reducing the risk of flu-related hospitalization by 38.5% and hospitalization for laboratory-confirmed influenza by 31.2%. While the high-dose shot kept more people out of the hospital, it did not show a significant difference in preventing deaths compared with the standard shot.

Kristoffer Grundtvig Skaarup et al, High-Dose vs Standard-Dose Influenza Vaccines in Older Adults, JAMA Network Open (2026). DOI: 10.1001/jamanetworkopen.2026.14620

Comment by Dr. Krishna Kumari Challa on Saturday

Venus flytrap's snap may come from rapid cell wall softening, not water flow

The Venus flytrap (Dionaea muscipula) is a marvel of nature, a highly effective killer that doesn't have to move an inch to capture and kill its prey. It releases a fruity nectar scent to attract flies and other insects. After they land in the trap, tiny hairs are triggered and the leaves shut with impressive speed.

 A new study by researchers published in the journal Science has offered a new explanation for how the carnivorous plant does it. 

To understand what could be driving it, the research team first filmed the closure using high-speed 3D cameras. Then, to see how leaf cells move without the entire leaf slamming shut, they cut the traps into thin strips or mechanically clamped them open. This revealed that the trap's underlying bending motion takes 3 to 4 seconds, but the leaf's curved shape forces it to shut in a fraction of a second.

Next, the scientists measured the mechanical stiffness of individual cells using a tiny probe before, during and after a triggering event. They discovered that the outer cells suddenly lost their stiffness, meaning either the fluid pressure inside the cells had dropped or the cell walls had relaxed.

Finally, the team used 3D surface scans of leaf layers and computer models to see how these cells changed shape. They showed that the cells bulged outward more after triggering, confirming that the reduced stiffness was due to cell walls softening rapidly rather than a loss of water pressure.

Closure occurs too quickly to be explained by water transport, revealing a distinct, nonhydraulic mechanism: a rapid (about one second) softening of the epidermal cell wall, releasing elastic energy stored in the trap," the scientists wrote in their paper. "Our finding reveals a mode of plant motility based on dynamic tuning of material properties, suggesting principles for muscle-free, bioinspired actuation."

Jeongeun Ryu et al, Fast cell wall softening causes Venus flytrap closure, Science (2026). DOI: 10.1126/science.aed5051

Comment by Dr. Krishna Kumari Challa on Friday

People with traumatic brain injury more likely to die from brain cancer than general population
Individuals with traumatic brain injury (TBI) have a 1.75-fold increased risk of dying from brain cancer compared to the general population, with the risk especially high among those with gunshot-related injuries and mild but complicated TBI. These findings indicate a need for long-term monitoring of brain cancer in certain TBI survivors and highlight TBI as a condition with potential long-term oncological consequences.

Charlotte B. Luster et al, Brain Cancer Mortality following Traumatic Brain Injury (TBI): A TBI Model Systems Study, Neuroepidemiology (2026). DOI: 10.1159/000552405

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