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Comment by Dr. Krishna Kumari Challa on August 12, 2025 at 12:33pm

Body hides its own RNA from the immune system with sugar

To our immune system, naked RNA is a sign of a viral or bacterial invasion and must be attacked. But our own cells also have RNA. To ward off trouble, our cells clothe their RNA in sugars, researchers  report in Nature.

Ribonucleic acid (RNA) is a family of large biological molecules fundamental to all forms of life, including viruses, bacteria, and animals. Viruses as diverse as measles, influenza, SARS-CoV-2, and rabies all have RNA, which is why the immune system starts attacking when it sees RNA in the bloodstream or in other inappropriate locations. But our own cells have RNA as well, sometimes displaying it on their surface, plain for roaming immune cells to see—and yet the immune system ignores it.

Recognizing RNA as a sign of infection is problematic, as every single cell in our body has RNA. The question is, how does our immune system distinguish our own RNA from that of dangerous invaders?

Researchers had noticed that our bodies add sugars onto RNA. These sugarcoated RNAs (also known as glycosylated RNAs, or glycoRNAs) are displayed on the cell surface and don't seem to provoke the immune system.

When the researchers took glycoRNA from human cell cultures and blood, cut off the sugars, and reintroduced it into cells, the immune cells attacked it. The immune cells had ignored the same RNA when it was sugarcoated.

The sugarcoating hides our own RNA from the immune system.

It is particularly significant to our body because cells are often covered by glycoRNAs. When cells die and are cleaned up by the immune system, the sugarcoating of RNA prevents dead cells from unnecessarily stimulating inflammation.

The findings could help when thinking about autoimmune diseases. Certain autoimmune diseases, such as lupus, are associated with specific RNA and dead cells setting off the immune system.

Now that scientists understand the role of RNA glycosylation in deflecting immune system attention, they can check on whether that strategy is somehow going awry, and, if so, how it might be fixed.

Vincent R. Graziano et al, RNA N-glycosylation enables immune evasion and homeostatic efferocytosis, Nature (2025). DOI: 10.1038/s41586-025-09310-6

Comment by Dr. Krishna Kumari Challa on August 12, 2025 at 9:43am

The researchers of this study, in a previous paper, reported that hypergravity of 10g surprisingly increased the rate of photosynthesis in Physcomitrium patens, but underlying anatomical and genetic mechanisms remained unexplored.

For this study, the team grew moss for eight weeks at 25°C under varying gravity levels—1g (control), 3g, 6g, and 10g—using a custom-built centrifuge with a built-in light-emitting diode (LED) for providing a photosynthetic photon.

To track the effect of hypergravity, they measured photosynthesis rates, anatomical traits like chloroplast size and gametophore number, and CO2 conductance—the ability of small openings on leaf surfaces to let CO2 in. They also carried out RNA sequencing to investigate if genes were expressed differently under hypergravity.
The results indicated an increased photosynthesis rate at higher gravity levels (6g and 10g) due to improved CO2 diffusion, resulting from the presence of more leafy shoots and larger chloroplasts.

This response was linked with the upregulation of AP2/ERF transcription factors, particularly IBSH1. The researchers confirmed its role by manipulating IBSH1 in moss—overexpression reproduced the effects of hypergravity, while repression prevented these responses.

The researchers suggest that the formation of a remarkable gene network involving AP2/ERF factors may have been a key factor in enabling moss plants to adapt to life on land during the evolution of plants. They think  these findings offer pivotal insights that could one day support agricultural production in space, where gravity is vastly different from Earth's.

 Yuko T. Hanba et al, First contact with greater gravity: Moss plants adapted via enhanced photosynthesis mediated by AP2/ERF transcription factors, Science Advances (2025). DOI: 10.1126/sciadv.ado8664

Part 2

Comment by Dr. Krishna Kumari Challa on August 12, 2025 at 9:42am

Hypergravity boosts food production in moss species, new study finds

Unless one is a trained fighter jet pilot, or a Formula 1 driver, humans tend not to do well at higher gravity, but tiny green moss plants seem to thrive under such conditions.

Researchers found that moss (Physcomitrium patens) exhibited increased photosynthesis under hypergravity conditions (six and 10 times Earth's gravity) due to enhanced carbon dioxide  (CO₂) diffusion from the atmosphere into the chloroplasts within the plant leaves.

The plants adapt to the increased gravity by increasing the size of their chloroplasts and the number of leafy shoots of the moss (gametophores). Researchers identified for the first time the gene factor responsible for this response. They named the factor ISSUNBOSHI1 or IBSH1, a namesake of an inch-high, warrior boy from a beloved Japanese fairytale.

The findings, published in Science Advances, reveal the existence of a key genetic mechanism that drove the evolutionary process, enabling plants to adapt to life on land.

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Plants began their journey on Earth under water. One of the biggest environmental changes they had to adapt to was their emergence onto the land, approximately 500 million years ago.

The early plants transitioning from aquatic to terrestrial ecosystems lost their buoyancy and were now exposed to the gravitational acceleration of 1g. In the reduced gravity of water, plants didn't have to worry about carrying their own weight, but on land, they had to.

As a result, their anatomy began to shift, developing plant tissues that provided structural reinforcement and orienting the light-harvesting components of plants towards the light. Even the cell wall saw some structural changes.

Part 1

Comment by Dr. Krishna Kumari Challa on August 12, 2025 at 8:53am

New evidence suggests Neolithic farmers cannibalized enemies

Slicing, chopping and bite and cut marks on human remains from 5,700 years ago suggest that cannibalism may have been a common practice among our Neolithic ancestors.

Researchers studied more than 600 bones and fragments from 11 well-preserved skeletons of adults, adolescents and children. They were found in El Mirador Cave in the Atapuerca mountains and date to the Late Neolithic period (about 6,500 to 5,000 years ago).

The work is published in the journal Scientific Reports.

Microscopy analysis revealed signs of cannibalism on all of the bones studied. Specifically, the researchers noted signs of butchery on 69 bones and chop marks on several others, indicating that skin and muscle had been sliced off. Some bones were translucent with slightly rounded edges, suggesting they had been boiled. Further evidence includes some of the larger bones being cracked open, most likely to get at the marrow.

According to the scientists, cannibalism took place after death. The bodies were skinned, and their limbs were separated before being cooked and eaten, possibly over a few days.

Ancient cannibalism is difficult to interpret because it can be hard to determine the motive, and evidence is often sparse or ambiguous at best. However, the scientists have ruled out emergency survival due to a lack of food, as there were no signs of scarcity in the region at the time. They also believe it wasn't part of funerary practices or other rituals, as nothing similar has been found in the area.

The bones in this study are thought to be from one family or an extended family, and researchers think a neighboring group wiped them out in a single event. "The current findings suggest that cannibalism may be linked to intergroup violence during late prehistoric periods," write the researchers in their paper. This is supported by evidence of other Neolithic massacres in Spain, France and Germany.

El Mirador cave, where the bones were found, is a treasure trove of archaeological remains. Previous discoveries include ceremonial skull caps and evidence of Bronze Age cannibalism.

This latest study, along with earlier findings, is challenging the common image of the Neolithic as an era of farmers coexisting peacefully. Instead, it suggests a more violent and conflict-ridden existence.

Palmira Saladié et al, Evidence of neolithic cannibalism among farming communities at El Mirador cave, Sierra de Atapuerca, Spain, Scientific Reports (2025). DOI: 10.1038/s41598-025-10266-w

Comment by Dr. Krishna Kumari Challa on August 9, 2025 at 10:12am

Sunlight-activated material turns PFAS in water into harmless fluoride

Researchers  have developed a sunlight-activated material that can degrade per- and polyfluoroalkyl substances (PFAS) in water, breaking down the pollutant into harmless components, including fluoride. The work is published in the journal Small.

The breakthrough discovery represents a promising low-energy solution for PFAS remediation, with potential applications in water treatment and environmental cleanup.

Many water contaminants are degraded by adding a reactive chemical that binds to the carbon. However, in PFAS molecules, the carbon atoms are protected in such a way that makes this process nearly impossible.

The researchers now have altered conditions and optimized the catalyst to target the PFAS-protective F atoms, which resulted in complete breakdown of the forever chemicals.

The produced fluoride can be isolated and used in health care products such as toothpaste or as additives to fertilizers.

Mahmoud Adel Hamza et al, CdIn2S4 Micro‐Pyramids for Reductive Photocatalytic Degradation of Perfluorooctanesulfonic Acid, Small (2025). DOI: 10.1002/smll.202504601

Comment by Dr. Krishna Kumari Challa on August 8, 2025 at 2:18pm

Peacocks have lasers in their tails

As if the tail of a peacock could get any more flamboyant. Scientists have now discovered yellow-green lasers shooting from the ‘eyes’ of their feathers. These aren’t vaporizing beams of light that can cut a bird in half or anything. We would have probably noticed that during a courtship display… The lasers we’re talking about are completely harmless. The term stands for Light Amplification by Stimulated Emission of Radiation. Essentially, that means if you shine a light on some materials and the atoms excite one another, it can release a flood of photons, producing a faint glow. Biological lasers like these can be found in butterfly wings and marine mammals. But this is the first time scientists have observed the effect in the feathers of peacocks. Even the greatest show-offs in the world have a secret or two up their sleeves.

The researchers found evidence of optical cavities in the form of resonating nanostructures in different parts of the eyespot, all faintly emitting two different wavelengths: green and yellow/orange.

Exactly what kind of structure is responsible for aligning the amplified light at these colors isn't clear. But the fact they are found across the feather, all emitting the same precise wavelengths in a signature fashion, is a sign that something strange is at work.

https://www.nature.com/articles/s41598-025-04039-8

Comment by Dr. Krishna Kumari Challa on August 8, 2025 at 1:51pm

Human eggs are protected from age-related genetic mutations, mtDNA study finds

As we age, the genes in our cells accumulate more mutations. This is one of the contributory factors to age-related diseases and the aging process. However, in a new study published in Science Advances, researchers have discovered one exception where genetic mutations don't appear to build up as humans get older—the mitochondrial DNA (mtDNA) of human egg cells in women.

Mitochondria are the energy powerhouses of the cell. These oval-shaped organelles supply most of the energy for a cell to function, have their own DNA and are only passed down from mothers to their children. Most mitochondrial DNA mutations are harmless, but some can cause diseases such as Leigh Syndrome in children, which can lead to seizures, loss of previously acquired motor skills and heart problems. It was previously unclear, though, whether these mutations increase with age in immature egg cells known as oocytes.

In this new study, scientists used a DNA-sequencing technique to identify mutations in 80 single oocytes from 22 women, aged 20 to 42. They also studied mitochondrial DNA mutations in the women's blood and saliva.

They found that as women age, mitochondrial DNA mutations increase in blood and saliva cells, but not in egg cells. This suggests that a mechanism may have evolved that protects eggs from age-related genetic damage seen in other parts of the body.

"mtDNA in human oocytes is protected against accumulation of mutations with aging and has functional consequences," wrote the researchers. "These findings are particularly timely as humans tend to reproduce later in life."

The researchers also noted that the few mutations they did find tended to occur in parts of the mtDNA that do not make proteins (non-coding regions). Mutations were much less common in the parts that make proteins (coding regions).

Previous studies have shown that older mothers are more likely to pass on chromosomal abnormalities to their children. It was assumed the same was true for mitochondrial mutations. The new research challenges this assumption, offering a promising sign that delaying motherhood may not increase the risk of passing on mtDNA mutations.

Despite these findings, the study's conclusions are not definitive. It was based on a small sample size and did not cover a woman's full reproductive lifespan.

 Barbara Arbeithuber et al, Allele frequency selection and no age-related increase in human oocyte mitochondrial mutations, Science Advances (2025). DOI: 10.1126/sciadv.adw4954

Comment by Dr. Krishna Kumari Challa on August 7, 2025 at 11:28am

Why do some birds dance?

Cockatoos perform 30 distinct dance moves and may combine them in unique ways

Captive cockatoos have at least 30 different dance moves in their repertoire, including headbanging and body rolls, according to a new study.

 The moves, of which 17 are newly identified, may be performed with or without music.

Several species of parrot have been anecdotally observed dancing to music in captivity. Dancing results from complex brain processes including imitation, learning and synchronized, rhythmic movement. Spontaneous dancing in time to music has only been reported in humans and parrots, although some wild birds also display rhythmic movements as part of their courtship displays.

Researchers analyzed 45 videos posted on social media that showed cockatoos (Cacatuidae) dancing. They identified a total of 30 distinct dance movements—17 of which had not previously been described scientifically. These newly identified dance moves included headbanging, sidesteps and body rolls.

The researchers found that some birds also performed their own individual dance moves, often by combining several of the movements in unique ways. Closely related species did not display more similar dances, and each species had a unique top 10 most common dance moves.

Comment by Dr. Krishna Kumari Challa on August 7, 2025 at 10:16am

Researchers discover universal rules of quantum entanglement across all dimensions

A team of theoretical researchers used thermal effective theory to demonstrate that quantum entanglement follows universal rules across all dimensions. Their study was published online in Physical Review Letters.

In classical physics, two particles that are far apart behave independently. However, in quantum physics, two particles can exhibit strong correlations regardless of the distance between them. This quantum correlation is known as quantum entanglement.

Quantum entanglement is a fundamental phenomenon underlying quantum technologies such as quantum computation and quantum communication, and understanding its structure is important both theoretically and practically.

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One of the key measures used to quantify quantum entanglement is the Rényi entropy. Rényi entropy quantifies the complexity of quantum states and the distribution of information, and plays a crucial role in the classification of quantum states and in assessing the feasibility of simulating quantum many-body systems.

Moreover, Rényi entropy serves as a powerful tool in theoretical investigations of the black hole information loss problem, and frequently appears in the context of quantum gravity.

 Most studies to date have been limited to (1+1)-dimensional systems, or 1 spatial dimension plus time dimension. In higher dimensions, analyzing the structure of quantum entanglement becomes significantly more difficult.

A group of researchers has shown the universal features of quantum entanglement structures in higher dimensions by applying theoretical techniques developed in the field of particle physics to quantum information theory.

The research team focused on the thermal effective theory, which has recently led to major advances in the analysis of higher-dimensional theories in particle physics. This is a theoretical framework designed to extract universal behavior from complex systems, based on the idea that observable quantities can often be characterized by only a small number of parameters.

By introducing this framework into quantum information theory, the team analyzed the behavior of Rényi entropy in higher-dimensional quantum systems.

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 Yuya Kusuki et al, Universality of Rényi Entropy in Conformal Field Theory, Physical Review Letters (2025). DOI: 10.1103/fsg7-bs7q

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Comment by Dr. Krishna Kumari Challa on August 7, 2025 at 9:46am

Anthropic says they've found a new way to stop AI from turning evil

AI is a relatively new tool, and despite its rapid deployment in nearly every aspect of our lives, researchers are still trying to figure out how its "personality traits" arise and how to control them. Large learning models (LLMs) use chatbots or "assistants" to interface with users, and some of these assistants have exhibited troubling behaviors recently, like praising evil dictators, using blackmail or displaying sycophantic behaviors with users. Considering how much these LLMs have already been integrated into our society, it is no surprise that researchers are trying to find ways to weed out undesirable behaviors.

Anthropic, the AI company and creator of the LLM Claude, recently released a paper on the arXiv preprint server discussing their new approach to reining in these undesirable traits in LLMs. In their method, they identify patterns of activity within an AI model's neural network—referred to as "persona vectors"—that control its character traits. Anthropic says these persona vectors are somewhat analogous to parts of the brain that "light up" when a person experiences a certain feeling or does a particular activity.

Anthropic's researchers used two open-source LLMs, Qwen 2.5-7B-Instruct and Llama-3.1-8B-Instruct, to test whether they could remove or manipulate these persona vectors to control the behaviors of the LLMs. Their study focuses on three traits: evil, sycophancy and hallucination (the LLM's propensity to make up information). Traits must be given a name and an explicit description for the vectors to be properly identified.

In their method, a technique called "steering" can be used to control behaviors. They write, "When we steer the model with the 'evil' persona vector, we start to see it talking about unethical acts; when we steer with 'sycophancy,' it sucks up to the user; and when we steer with 'hallucination,' it starts to make up information. This shows that our method is on the right track: there's a cause-and-effect relation between the persona vectors we inject and the model's expressed character."

However, they found that when they made these changes after training, the model loses some of its intelligence. But there was a workaround—the team found that inducing the bad behaviors during training allowed the LLMs to integrate better behavior without reducing their usefulness. Furthermore, they found that they can monitor and predict persona shifts during deployment and training and flag problematic training data that is more likely to produce unwanted traits, even before fine-tuning the model.

Runjin Chen et al, Persona Vectors: Monitoring and Controlling Character Traits in Language Models, arXiv (2025). DOI: 10.48550/arxiv.2507.21509

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