Climate change is overhauling marine nutrient cycles, scientists say

Computer models reveal how human-driven climate change will dramatically overhaul critical nutrient cycles in the ocean. In the Proceedings of the National Academy of Sciences,  researchers report evidence that marine nutrient cycles—essential for sustaining ocean ecosystems—are changing in unexpected ways as the planet continues to warm.

Model studies have suggested that when the ocean warms it gets more stratified, which can drain certain parts of the surface ocean of nutrients. 

Although models suggest a connection between ocean temperatures and surface ocean nutrients, this is the first study to confirm climate change's impacts on nutrient cycles.

The researchers  discovered that over the last half-century, there's been a major decline in phosphorus—a nutrient that plays a key role in the health of marine food webs—in southern hemisphere oceans.

There can be cascading effects up the food web, they say. Because plankton—microorganisms that form the bases of many marine food webs—rely on phosphorous as a food source. "When phytoplankton have less phosphorus, they become less nutritious, which can impair zooplankton and fish growth rates."

Surprisingly, concentrations of nitrate—a nutrient the team expected to decline—appear to remain steady. Nitrate is crucial for ecosystem functioning, so that it's not in decline is a good sign.

Nevertheless, nitrate concentrations may still decline in the future as the climate continues to change.

Skylar D. Gerace et al, Observed declines in upper ocean phosphate-to-nitrate availability, Proceedings of the National Academy of Sciences (2025). DOI: 10.1073/pnas.2411835122

Decoding a butterfly's travel map: Scientists find globetrotting not in genes

Painted lady butterflies are world travelers. The ones we encounter in Europe fly from Africa to Sweden, ultimately returning to areas north and south of the Sahara. But what determines whether some butterflies travel long distances while others travel short distances? A group of scientists shows that the different migration strategies are shaped by environmental conditions rather than being encoded in the butterfly's DNA.

Researchers, alongside citizen science projects, have been trying to decode the butterfly travel map. Their interdisciplinary publication provides new insights.

The results are now published in PNAS Nexus.

The painted lady is a strikingly beautiful and colorful butterfly species. But what makes them particularly special is their incredible long-distance migrations.

These butterflies go on a yearly 10,000 km journey between Africa and Europe. They do so through a succession of generations, looking for the best breeding conditions for their offspring. Each individual travels in one section of the annual migratory cycle, with its offspring continuing their journey.

The colorful insects begin their grand voyage in spring, starting from Northwest Africa and flying over the Mediterranean Sea to Europe. Subsequent generations then make their way to Great Britain, even reaching the Arctic tundra of Sweden to spend the summer.

Until recently, it was believed that once the butterflies reach Sweden, they perish due to the colder climates that arise there at the end of summer. However, studies have shown that painted ladies return to warmer regions in autumn, confirming a circular migratory pattern. While some end up staying in the Mediterranean area, others travel back to Africa, even crossing the Sahara. But how come?

Researchers set out to understand this phenomenon.

They utilized isotope geolocation to estimate the geographic origin of each butterfly. The key principle of this method is that the isotopic makeup—or the stable isotopes—of the adult butterfly's wings mirrors the isotopic signature of the plants they ate as a caterpillar. 

 Isotopes are different forms of the same element, with identical chemical properties but slightly different atomic masses.

The researchers spent several years developing this technique, testing different isotopes, refining statistical approaches, and incorporating machine-learning techniques to enhance accuracy and resolution.

The analysis confirmed the diverse travel behavior among individuals: some took a long migration trip south from Scandinavia, crossing the Sahara, while others migrated a short distance, staying north of the desert in the Mediterranean region.

The scientists then used whole genome sequencing to compare DNA sequences of each individual. Interestingly, there was no genetic difference between short-trip and long-trip butterflies.

Part 1

This finding fundamentally differs from what is observed in some birds, another well-studied migratory group. For example, in willow warblers, a large chromosomal region has been associated with variable migratory direction, illustrating how different phenotypes arise from distinct genomic compositions.

Additionally, migration patterns in painted ladies could not be associated with factors such as sex, wing size, or wing shape.

According to the scientists, so-called phenotypic plasticity might explain the different migration styles. "Phenotypic plasticity is the ability of an organism to change its phenotype—in this case, its engagement in long- or short-distance migration—in response to environmental conditions without altering its genetic makeup.
For instance, in summer, butterflies in Sweden might be prompted to migrate a long distance south across the Sahara due to the quick shift in day lengths or other seasonal cues. In contrast, butterflies in Southern France, where the days are longer, may not encounter those migratory cues and therefore only undertake short-distance journeys, staying in the Mediterranean area.

Megan S Reich et al. Isotope geolocation and population genomics in Vanessa cardui: Short- and long-distance migrants are genetically undifferentiated, PNAS Nexus (2025). DOI: 10.1093/pnasnexus/pgae586. academic.oup.com/pnasnexus/art … /4/2/pgae586/7994570

Part 2

How eye saccades enable mammals to simultaneously chase prey and navigate through complex environments

How do predators use their vision to both navigate through the terrain while tracking prey running for its life? Pursuing prey through a complex environment is a major challenge for the visual system, as not only does the prey constantly change direction, sometimes in the opposite direction to the pursuer, but running after something evokes self-induced motion-blur that degrades vision.

To investigate this question, researchers reconstructed the visual fields of freely moving ferrets that were chasing a fleeing target and discovered that eye saccades (very rapid coordinated eye movements) align the world motion—and not the actual thing they are chasing—to the retina and retinal specializations used for high-acuity vision.

Saccades achieve this by countering head rotations to align the area of the sharpest vision with the direction of intended travel and the area of the least motion-induced blur. This enables image blur, which degrades vision, to be minimized over these specialized retinal areas during turns when chasing targets that are trying to evade capture.

These eye movements are seen in freely moving ferrets, mice, rats and tree shrews, suggesting a generalized mechanism enabling mammals to navigate complex environments during pursuit.

The research is published in the journal Current Biology.

 Eye saccades align optic flow with retinal specializations during object pursuit in freely moving ferrets, Current Biology (2025). DOI: 10.1016/j.cub.2024.12.032. www.cell.com/current-biology/f … 0960-9822(24)01700-7

Human influence has led to loss of dialects in chimpanzees, long-term study suggests

A new study, conducted on wild chimpanzees (Pan troglodytes verus) in Taï National Park, Côte d'Ivoire, provides evidence that the gestures used by male chimpanzees from four neighboring communities during copulation requests may reflect different dialects. One gesture, used predominantly in one community, disappeared from the repertoire 20 years ago after a poaching incident and did not return. This incident documents a cultural loss associated with human-induced population decline, a phenomenon rarely documented in animals.

Much like people from different regions speak with different accents or use unique expressions, many animals have their own "dialects." Songbirds such as sparrows and finches, or even whales, learn their songs from others, resulting in variations that are as unique to a region as local accents in humans. However, in primates, which are phylogenetically closer to humans, evidence for community-specific dialects remains surprisingly scarce, presenting an intriguing area for further scientific investigation.

Researchers observed members of the four neighboring communities of wild chimpanzees every day from the time they left their nests in the morning until they went to sleep at night. Their work is published  in the journal Current Biology.

Researchers identified four types of communicative gestures, 'heel kick,' 'knuckle knock,' 'leaf clip' and 'branch shake,' used by male chimpanzees to attract females to mate with them. Between 2013 and 2024, they found differences in the frequency of use of these communicative gestures between neighboring chimpanzee communities, but also between populations across Africa.

Using long-term data from 45 years of research in the Taï Chimpanzee Project, the researchers also revealed variations in gesture use over time. These findings highlight the ability of humans' closest living relatives to produce cultural differences in communicative signals.

The consistent use of the same mating request signal forms within communities, but different signal forms between neighboring communities that experience regular gene flow through female migration, suggests socially learned dialects in chimpanzees, evidence that has rarely been demonstrated before.

These days, males in the North group, one of the four communities, have not been observed to use the 'knuckle knock' for 20 years, although all males in the North group used this gesture before 2004.

Following a series of human-induced events leading to demographic loss, the last adult male of the North group was killed by a poacher, resulting in several years without an adult male.

The loss of competition between adult males for females or the loss of all role models could be responsible for the cultural loss of this specific copulation request gesture in this community.

This finding provides evidence that human illegal activities have altered the cultural behavior of chimpanzees.

There is an urgent need to integrate the preservation of chimpanzee culture into conservation strategies, the researchers say.

Mathieu Malherbe et al, Signal traditions and cultural loss in chimpanzees, Current Biology (2025). DOI: 10.1016/j.cub.2024.12.008

Phage Therapy: Helping viruses deliver a knockout blow to killer bacterial infections

In the face of rising concerns about antibiotic resistant infections, an international group of microbial experts have launched a powerful and flexible free online genomic toolkit for more rapid development of phage therapy.

After decades of research, phages or bacteriophage viruses that target and kill specific bacteria are seen as the next frontier in finding fast and effective ways to curb the death toll and serious illnesses caused by antibiotic resistant "superbugs" every year.

The lead developers of the new platform, called Sphae, claim it is capable of assessing if a phage is suitable for a targeted therapy in under 10 minutes.

This marks a big step forward in quickly evaluating phage safety and suitability for addressing antibiotic-resistant infections, according to the team at Flinders Accelerator for Microbiome Exploration (FAME) and collaborators in a new article just published in the journal Bioinformatics Advances.

Sphae integrates high-throughput sequencing technologies with advanced computational pipelines, enabling researchers to analyze vast and complex datasets efficiently. It  prioritizes safety, flagging genes associated with toxins or undesirable traits to ensure that only the safest candidates are advanced for therapeutic use.

Adaptability and scalability sets Sphae apart. The workflow supports a wide range of sequencing technologies while the toolkit can handle the massive datasets typical of high-performance computing environments, making it an invaluable tool for labs tackling large-scale projects.

Sphae not only aids in therapeutic research but also advances our broader understanding of microbial ecosystems and their impact on global health and climate. Sphae processes multiple phage genomes at once, saving time and efficiently handling larger datasets.

Sphae works effectively even in mixed or challenging datasets, providing consistent and accurate results to help identify phages that can potentially combat resistant bacterial strains.

It offers a complete view of phage genomes, summarizing key features like resistance and virulence markers for better insight into phage safety and functionality.

When conventional antibiotics are not effective any more, personalized phage therapy could become a standard part of medical practice by simplifying and accelerating the discovery of therapeutic phages suited to the individual patient's infection. The future of medicine lies in the precise, efficient, and safe use of phages to combat bacterial infections and restore hope to patients worldwide.

Bhavya Papudeshi et al, Sphae: an automated toolkit for predicting phage therapy candidates from sequencing data, Bioinformatics Advances (2025). DOI: 10.1093/bioadv/vbaf004

Image source : tandfonline.com

Part 2

Hungry fat cells could  starve cancer to death

Liposuction and plastic surgery aren't often mentioned in the same breath as cancer. But they are the inspiration for a new approach to treating cancer that uses engineered fat cells to deprive tumors of nutrition.

Researchers  used the gene editing technology CRISPR to turn ordinary white fat cells into "beige" fat cells, which voraciously consume calories to make heat.

Then, they implanted them near tumors the way plastic surgeons inject fat from one part of the body to plump up another. The fat cells scarfed up all the nutrients, starving most of the tumor cells to death. The approach even worked when the fat cells were implanted in mice far from the sites of their tumors. Relying on common procedures could hasten the approach's arrival as a new form of cellular therapy.

Doctors already routinely remove fat cells with liposuction and put them back via plastic surgery. These fat cells can be easily manipulated in the lab and safely placed back into the body, making them an attractive platform for cellular therapy, including for cancer.

Beige fat cells outcompete cancer cells for nutrients. That is why exposure to cold could suppress cancer in mice.

One remarkable experiment even showed it could help a patient with non-Hodgkin lymphoma. Scientists concluded that the cancer cells were starving because the cold was activating brown fat cells, which use nutrients to produce heat.

But cold therapy isn't a viable option for cancer patients with fragile health.

So the researchers turned to the idea of using beige fat, wagering that they could engineer it to burn enough calories, even in the absence of cold, to deprive tumors of the fuel they needed to grow.

Part 1

They used CRISPR to activate genes that are dormant in white fat cells but are active in brown fat cells, in the hopes of finding the ones that would transform the white fat cells into the hungriest of beige fat cells.

A gene called UCP1 rose to the top.

Then, the researchers grew UCP1 beige fat cells and cancer cells in a "trans-well" petri dish. The cancer cells were on the bottom and the fat cells were above them in separate compartments that kept the cells apart but forced them to share nutrients.

The results were shocking.
In their very first trans-well experiment, very few cancer cells survived.
The beige fat cells held sway over two different types of breast cancer cells, as well as colon, pancreatic and prostate cancer cells.

But the researchers still didn't know if the implanted beige fat cells would work in a more realistic context.
So, the scientists turned to fat organoids, which are coherent clumps of cells grown in a dish, to see if they could beat tumor cells when they were implanted next to tumors in mice.

The approach worked against breast cancer, as well as pancreatic and prostate cancer cells. The cancer cells starved as the fat cells gobbled up all the available nutrients.

The implanted beige fat cells were so powerful that they suppressed pancreatic and breast tumors in mice that were genetically predisposed to develop cancer. It even worked when the beige fat cells were implanted far away from the breast cancer cells.
When tested with removed cancer breasts, these same-patient beige fat cells outcompeted breast cancer cells in petri dishes—and when they were implanted together in mouse models.

Knowing that cancers have preferred diets, the researchers engineered fat just to eat certain nutrients. Certain forms of pancreatic cancer, for example, rely on uridine when glucose is scarce.

So, they programmed the fat to eat just uridine, and they easily outcompeted these pancreatic cancer cells. This suggests that fat could be adapted to any cancer's dietary preferences.
Fat cells have many advantages when it comes to living cell therapies.

Hai P. Nguyen et al, Implantation of engineered adipocytes suppresses tumor progression in cancer models, Nature Biotechnology (2025). DOI: 10.1038/s41587-024-02551-2

Part 2

What is brown fat?

Juicing may harm your health in just 3 days, study finds

Think your juice cleanse is making you healthier? A new  study suggests it might be doing the opposite. The study, recently published in Nutrients, found that a vegetable and fruit juice-only diet—even for just three days—can trigger shifts in gut and oral bacteria linked to inflammation and cognitive decline.

Scientists studied three groups of healthy adults. One group consumed only juice, another had juice with whole foods and a third ate only whole plant-based foods. Scientists collected saliva, cheek swabs and stool samples before, during and after the diets to analyze bacterial changes using gene-sequencing techniques.

The juice-only group showed the most significant increase in bacteria associated with inflammation and gut permeability, while the plant-based whole food group saw more favorable microbial changes. The juice plus food group had some bacterial shifts but less severe than the juice-only group. These findings suggest that juicing without fiber may disrupt the microbiome, potentially leading to long-term health consequences.

Most people think of juicing as a healthy cleanse, but this study offers a reality check, say the researchers.

Consuming large amounts of juice with little fiber may lead to microbiome imbalances that could have negative consequences, such as inflammation and reduced gut health.

Fiber matters

Juicing strips away much of the fiber in whole fruits and vegetables, which feeds beneficial bacteria that produce anti-inflammatory compounds such as butyrate.

Without fiber, sugar-loving bacteria can multiply. The high sugar content in juice further fuels these harmful bacteria, disrupting the gut and oral microbiome. The study also suggests that reduced fiber intake may impact metabolism, immunity and even mental health.

Unlike the gut microbiota, which remained relatively stable, the oral microbiome showed dramatic changes during the juice-only diet. Scientists found a reduction in beneficial Firmicutes bacteria and an increase in Proteobacteria, a bacterial group associated with inflammation.

This highlights how quickly dietary choices can influence health-related bacterial populations. The oral microbiome appears to be a rapid barometer of dietary impact.

So don't just drink juices, eat whole fruits and vegetables, with their fibre intact.

Maria Luisa Savo Sardaro et al, Effects of Vegetable and Fruit Juicing on Gut and Oral Microbiome Composition, Nutrients (2025). DOI: 10.3390/nu17030458

Gray matter study uncovers two neuroanatomically different OCD subtypes

Obsessive compulsive disorder (OCD) is a mental health disorder associated with persistent, intrusive thoughts (i.e., obsessions), accompanied by repetitive behaviors (i.e., compulsions) aimed at reducing the anxiety arising from obsessions. Past studies have showed that people diagnosed with OCD can present symptoms that vary significantly, as well as distinct brain abnormalities.

A team of researchers  recently carried out a study aimed at further exploring the well-documented differences among patients with OCD. Their findings, published in Translational Psychiatry, allowed them to identify two broad OCD subtypes, which are associated with different patterns in gray matter volumes and disease epicenters.

OCD is a highly heterogeneous disorder, with notable variations among cases in structural brain abnormalities.

The researchers recruited 100 individuals who had just been diagnosed with OCD for the first time and had not yet started treatment, along with 106 healthy individuals who received no psychiatric and medical diagnoses. They then used magnetic resonance imaging (MRI) to collect to collect structural imaging scans of all the participants' brains.

Utilizing normative models of gray matter volume, the researchers identified subtypes based on individual morphological abnormalities.

Subtype 1 displayed significantly increased gray matter volume in regions including the frontal gyrus, precuneus, insula, hippocampus, parahippocampal gyrus, amygdala, and temporal gyrus, while subtype 2 exhibited decreased gray matter volume in the frontal gyrus, precuneus, insula, superior parietal gyrus, temporal gyrus, and fusiform gyrus," wrote the researchers in their paper. "When considering all patients collectively, structural brain abnormalities nullified."

Part 1

The two OCD subtypes uncovered by the researchers are characterized by distinct patterns in gray matter volumes within specific brain regions. People in subtype 1 presented more gray matter in brain areas supporting decision-making (e.g., the frontal gyrus) and emotional processing (i.e., the amygdala).

In contrast, those in subtype 2 were found to present lower gray matter volumes in areas linked to self-referential thinking (i.e., the precuneus) and cognitive function (i.e., the striatum).

Notably, the newly unveiled subtypes were also found to be associated with different disease epicenters and distinct links to neurotransmitter receptors in the brain. This essentially means that the brain regions and receptors most affected by or implicated in the disorder also differed significantly between the two subtypes.
Subtype 1 showed disease epicenters in the middle frontal gyrus, while subtype 2 displayed disease epicenters in the striatum, thalamus and hippocampus," wrote the researchers. "Furthermore, structural brain abnormalities in these subtypes displayed distinct associations with neurotransmitter receptors/transporters."

The findings of this recent study could help to partially explain the differences between patients diagnosed with OCD that have often been observed .

 Baohong Wen et al, Individualized gray matter morphological abnormalities unveil two neuroanatomical obsessive-compulsive disorder subtypes, Translational Psychiatry (2025). DOI: 10.1038/s41398-025-03226-5

Part 2

Generally, things really do seem better in the morning, large study suggests

Generally, things really do seem better in the morning, with clear differences in self-reported mental health and well-being across the day, suggest the findings of a large study published in the open access journal BMJ Mental Health.

People generally wake up feeling in the best frame of mind in the morning, but in the worst around midnight, the findings indicate, with day of the week and season of the year also playing their part.

Mental health and well-being are dynamic in nature, and subject to change over both short and extended periods, note the researchers. But relatively few studies have looked at how these might change over the course of the day, and those studies that have, have included particular, or only small, groups.

The researchers therefore wanted to explore whether time of day was associated with variations in mental health (depressive and/or anxiety symptoms), happiness (hedonic well-being), life satisfaction, sense of life being worthwhile (eudemonic well-being) and loneliness (social well-being). They also wanted to find out if these associations varied by day, season, and year. They analyzed data from the University College London COVID-19 Social Study, which began in March 2020, and involved regular monitoring until November 2021, and then additional monitoring up to March 2022.

All studied aspects were measured via questionnaires using validated assessment tools or through single direct questions.

Analysis of the data revealed a clear pattern in self-reported mental health and well-being across the day, with people generally waking up in the morning feeling best—lowest depressive/anxiety symptoms and loneliness and highest happiness, life satisfaction, and worthwhile ratings—and feeling worst around midnight.

The influence of day of the week was less clear-cut, with more variation in mental health and well-being during weekends than on weekdays.

Happiness, life satisfaction, and worthwhile ratings were all higher on Mondays and Fridays than on Sundays, and happiness was also higher on Tuesdays. But there was no evidence that loneliness differed across days of the week.

There was clear evidence of a seasonal influence on mood, however. Compared with winter, people tended to have lower levels of depressive and anxiety symptoms and loneliness, and higher levels of happiness, life satisfaction, and feeling that life was worthwhile in other seasons.

And mental health was best in the summer across all outcomes. But the season didn't affect the associations observed across the day, however.

Mental health and well-being also steadily improved from 2020, the first year of the COVID-19 pandemic.

This is an observational study, and as such, can't establish cause. 

Will things feel better in the morning? A time-of-day analysis of mental health and wellbeing from nearly 1 million observations, BMJ Mental Health (2025). DOI: 10.1136/bmjment-2024-301418

**

Kids use different math skills at work vs. school, India study shows

In India, many kids who work in retail markets have good math skills. They can quickly perform a range of calculations to complete transactions. But as a new study shows, these kids often perform much worse on the same kinds of problems as they are taught in the classroom. This happens even though many of these students still attend school or attended school through 7th or 8th grades.

Conversely, the study also finds, Indian students who are still enrolled in school and don't have jobs do better on school-type math problems, but they often fare poorly at the kinds of problems that occur in marketplaces.

Overall, both the "market kids" and the "school kids" struggle with the approach the other group is proficient in, raising questions about how to help both groups learn math more comprehensively.

For the school kids, they do worse when you go from an abstract problem to a concrete problem. For the market kids, it's the opposite.

Indeed, the kids with jobs who are also in school "underperform despite being extraordinarily good at mental math".

The paper, "Children's arithmetic skills do not transfer between applied and ac...," is published in Nature.

So why might the performance of the nonworking students decline when given a problem in market conditions?

"They learned an algorithm but didn't understand it!"

Meanwhile, the market kids seemed to use certain tactics to handle retail transactions. For one thing, they appear to use rounding well. Take a problem like 43 times 11. To handle that intuitively, you might multiply 43 times 10, and then add 43, for the final answer of 473. This appears to be what they are doing.

The market kids are able to exploit base 10, so they do better on base 10 problems.

The school kids have no idea. It makes no difference to them. The market kids may have additional tricks of this sort.

 On the other hand, the school kids had a better grasp of formal written methods of division, subtraction, and more.

Finding a way to cross the divide between informal and formal ways of tackling math problems, then, could notably help some Indian children.

The fact that such a divide exists, meanwhile, suggests some new approaches could be tried in the classroom, say the researchers.These findings highlight the importance of educational curricula that bridge the gap between intuitive and formal mathematics.

Now I know why I  get confused with calculations when I visit the markets.

Esther Duflo, Children's arithmetic skills do not transfer between applied and academic mathematics, Nature (2025). DOI: 10.1038/s41586-024-08502-w. www.nature.com/articles/s41586-024-08502-w

Compact camera can identify objects at the speed of light

Researchers recently  have produced some eye-popping research, including shrinking a camera down to the size of a grain of salt while still capturing crisp, clear images.

Building on this work they, published a paper in Science Advances that describes a new kind of compact camera engineered for computer vision—a type of artificial intelligence that allows computers to recognize objects in images and video.

Their research prototype uses optics for computing, significantly reducing power consumption and enabling the camera to identify objects at the speed of light. Their device also represents a new approach to the field of computer vision.

Instead of using a traditional camera lens made out of glass or plastic, the optics in this camera relies on layers of 50 meta-lenses—flat, lightweight optical components that use microscopic nanostructures to manipulate light. The meta-lenses also function as an optical neural network, which is a computer system that is a form of artificial intelligence modeled on the human brain.

This unique approach has a couple of key advantages. First, it's fast. Because much of the computation takes place at the speed of light, the system can identify and classify images more than 200 times faster than neural networks that use conventional computer hardware, and with comparable accuracy. Second, because the optics in the camera rely on incoming light to operate, rather than electricity, the power consumption is greatly reduced.

Top climate scientists declare 2C climate goal 'dead'

Pathetic! The world is failing to recognize this catastrophe, acting on the warning of climate scientists and stopping it. 

Holding long-term global warming to two degrees Celsius—the fallback target of the Paris climate accord—is now "impossible," according to a stark new analysis published by leading scientists.

Led by renowned climatologist James Hansen, the paper appears in the journal Environment: Science and Policy for Sustainable Development and concludes that Earth's climate is more sensitive to rising green house gas emissions than previously thought.

Compounding the crisis, Hansen and colleagues argued, is a recent decline in sunlight-blocking aerosol pollution from the shipping industry, which had been mitigating some of the warming.

An ambitious climate change scenario outlined by the UN's climate panel, which gives the planet a 50 percent chance of keeping warming under 2C by the year 2100, "is an implausible scenario," the scientists say.

"That scenario is now impossible, the two degree target is dead."

Instead, the scientists argued, the amount of greenhouse gases already pumped into the atmosphere by burning fossil fuels meant increased warming is now guaranteed.

Temperatures will stay at or above 1.5C in the coming years—devastating coral reefs and fueling more intense storms—before rising to around 2.0C by 2045, they forecast.

They estimated polar ice melt and freshwater injection into the North Atlantic will trigger the shutdown of the Atlantic Meridional Overturning Circulation (AMOC) within the next 20-30 years.

The current brings warmth to various parts of the globe and also carries nutrients necessary to sustain ocean life.

Its end "will lock in major problems including sea level rise of several meters—thus, we describe AMOC shutdown as the 'point of no return,'" the scientists argued in their paper.

The world's nations agreed during the landmark Paris climate accord of 2015 to try to hold end-of-century warming to 1.5C above pre-industrial levels.

Scientists identified the threshold as critical to preventing the breakdown of major ocean circulation systems, the abrupt thawing of boreal permafrost, and the collapse of tropical coral reefs.

The 1.5C target has already been breached over the past two years, according to data from the EU's climate monitoring system Copernicus, though the Paris Agreement referred to a long-term trend over decades.

At 2C, the impacts would be even greater, including irreversible loss to Earth's ice sheets, mountain glaciers and snow, sea ice and permafrost.

The authors acknowledged the findings appeared grim, but argued that honesty is a necessary ingredient for change.

Failure to be realistic in climate assessment and failure to call out the fecklessness of current policies to stem global warming is not helpful to young people," they said.

But is the world listening?

James E. Hansen et al, Global Warming Has Accelerated: Are the United Nations and the Public Well-Informed?, Environment: Science and Policy for Sustainable Development (2025). DOI: 10.1080/00139157.2025.2434494

Electric vehicle batteries can last almost 40% longer in the real world than in lab tests

When we see "tested under laboratory conditions," we often assume real-world conditions will lead to faster degradation of a product.

But experts from Stanford University have found the opposite is true for electric vehicle (EV) batteries. Their new research shows traditional laboratory testing leads to faster degradation, while real-world use gives substantially more battery life, extending the lifespan of the entire EV. Researchers found the stop-start way we drive and the variable rate the battery discharges power actually prolongs battery life by up to 38% compared to traditional tests.

This is good news for EV drivers—and for efforts to electrify transport. This extra battery life would translate to more than 300,000 more kilometers an EV could drive before needing battery replacement, the researchers say.

Longer-lasting batteries would reduce the total cost of EV ownership—and benefit the environment by getting more use out of each battery.

https://www.nature.com/articles/s41560-024-01675-8

AI bias shapes everything from hiring to health care

Generative AI tools like ChatGPT, DeepSeek, Google's Gemini and Microsoft's Copilot are transforming industries at a rapid pace. However, as these large language models become less expensive and more widely used for critical decision-making, their built-in biases can distort outcomes and erode public trust.

Researchers published a study emphasizing the urgent need to address bias by developing and deploying ethical, explainable AI. This includes methods and policies that ensure fairness and transparency and reduce stereotypes and discrimination in LLM applications.

Xiahua Wei et al, Addressing bias in generative AI: Challenges and research opportunities in information management, Information & Management (2025). DOI: 10.1016/j.im.2025.104103

Why antibiotics can fail even against non-resistant bacteria

Antibiotics are indispensable for treating bacterial infections. But why are they sometimes ineffective, even when the bacteria are not resistant? In their latest study published in the journal Nature, researchers challenge the conventional view that a small subset of particularly resilient bacteria are responsible for the failure of antibiotic therapies.

In certain infectious diseases caused by bacteria, antibiotics are less effective than expected. One example is infections caused by Salmonella bacteria, which can lead to illnesses such as typhoid fever. For many years, researchers believed that a small subset of dormant bacteria was the main problem in fighting infections.

These so-called persisters can survive antibiotic treatment and cause relapses later. Researchers worldwide have been working on new therapies aimed at targeting and eliminating these "sleeping" bacteria.

In a new study,  scientists challenge the prevailing concept that persisters are the cause of antibiotic ineffectiveness.

Contrary to widespread belief, antibiotic failure is not caused by a small subset of persisters. In fact, the majority of Salmonella in infected tissues are difficult to kill. Scientists have been able to demonstrate that standard laboratory tests of antimicrobial clearance produce misleading results, giving a false impression of a small group of particularly resilient persisters.

Nutrient starvation increases Salmonella resilience

The researchers investigated antimicrobial clearance in both Salmonella-infected mice and tissue-mimicking laboratory models. The body's defense mechanisms against bacteria often include reducing the availability of nutrients. The researchers have now revealed that, in fact, this nutrient starvation is the main reason for Salmonella bacteria surviving treatments with antibiotics. The researchers assume that the same applies to other bacterial pathogens.

Under nutrient-scarce conditions, bacteria grow very slowly. This may seem good at first, but it is actually a problem because most antibiotics only gradually kill slowly growing bacteria. As a result, the drugs are much less effective, and relapses can occur even after prolonged therapy.

The scientists used an innovative method to monitor antibiotic action in single bacteria in real time. They demonstrated that nearly the entire Salmonella population survives antibiotic treatment for extended periods, not just a small subset of hyper-resilient persisters.

Joseph Fanous et al, Limited impact of Salmonella stress and persisters on antibiotic clearance, Nature (2025). DOI: 10.1038/s41586-024-08506-6. www.nature.com/articles/s41586-024-08506-6

 How RNA travels between cells to control genes across generations

RNA-based medicines are one of the most promising ways to fight human disease, as demonstrated by the recent successes of RNA vaccines and double-stranded RNA (dsRNA) therapies. But while health care providers can now successfully develop drugs that use dsRNA to accurately target and silence disease-causing genes, a major challenge remains: getting these potentially life-saving RNA molecules into cells efficiently.

A new study published in the journal eLife on February 4, 2025, may lead to breakthroughs in RNA-based drug development.

Researchers used microscopic roundworms as a model to investigate how dsRNA molecules naturally enter cells and influence many future generations. The team discovered multiple pathways for dsRNA to enter the worms' cells—a finding that could help improve drug delivery methods in humans.

Researchers learned that RNA molecules can carry specific instructions not just between cells but across many generations, which adds a new layer to our current understanding of how inheritance works.

The researchers  found that a protein called SID-1, which acts as a gatekeeper for the transfer of information using dsRNA, also has a role in regulating genes across generations.

When researchers removed the SID-1 protein, they observed that the worms unexpectedly became better at passing changes in gene expression to their offspring. In fact, these changes persisted for over 100 generations—even after SID-1 was restored to the worms.

Interestingly, you can find proteins similar to SID-1 in other animals, including humans. Understanding SID-1 and its role has significant implications for human medicine. If we can learn how this protein controls RNA transfer between cells, we could potentially develop better targeted treatments for human diseases and perhaps even control the inheritance of certain disease states.

The research team also discovered a gene called sdg-1 that helps regulate "jumping genes"—DNA sequences that tend to move or copy themselves to different locations on a chromosome. While jumping genes can introduce new genetic variations that may be beneficial, they are more likely to disrupt existing sequences and cause disease.

The researchers found that sdg-1 is located within a jumping gene but produces proteins that are used to control jumping genes, creating a self-regulating loop that could prevent unwanted movements and changes.

It's fascinating how these cellular mechanisms maintain this delicate balance, like a thermostat keeping a house at just the right temperature so it isn't too warm or too cold. The system needs to be flexible enough to allow some 'jumping' activity while preventing excessive movements that could harm the organism.

These findings  provide valuable insights into how animals regulate their own genes and maintain stable gene expression across generations. Studying these mechanisms could potentially pave the way for innovative future treatments for heritable diseases in humans.

 Nathan M Shugarts Devanapally et al, Intergenerational transport of double-stranded RNA in C. elegans can limit heritable epigenetic changes, eLife (2025). DOI: 10.7554/eLife.99149.3

Antibiotic resistance can spread unpredictably into the environment, living on mineral surfaces

Imagine one of world's many picturesque beaches, the waves lapping against the shore, the golden sand and the smooth pebbles. That sounds like a beautiful moment in time. But under the surface, there is more to the story.

A new study, published in Science of The Total Environment,  shows that the sand on that beach may contain antibiotic resistant DNA. Flow and currents in rivers, lakes, streams and the sea, suspend and move mineral particles making it possible for suspended DNA to attach and travel long distances.

The DNA that codes for antibiotic resistance may have been carried into the environment by wastewater from hospitals or farming. If left alone in the water column, the DNA will degrade fast, but if it binds to bypassing mineral surfaces the DNA can be stabilized and survive. Deposited minerals can thus act as a sort of gene library carrying genes from one environment to another, and this may cause antibiotic resistance to spread.

Even though the DNA is bound to the particles, local bacteria can incorporate the DNA and become resistant. Once incorporated, the resistance can spread rapidly to neighboring bacteria and to offspring. In this way, antibiotic resistance can spread unpredictably to new environments—even though these bacteria have never seen a high-resistance environment.

According to the new study, the type of mineral plays a large role for how fast bacteria can incorporate mineral-bound DNA and how fast the obtained trait is disseminated throughout a community. In addition, some mineral grains can both up-concentrate and preserve DNA, while others can only carry a few molecules.

The researchers hope to be able to find an antidote of sorts, a mineral compound that can prevent bacteria from incorporating the DNA or the DNA from spreading in biofilm.

Saghar Hendiani et al, Reconciling the role of mineral surfaces for bacterial evolution: Importance of minerals in the dissemination of antibiotic resistance, Science of The Total Environment (2025). DOI: 10.1016/j.scitotenv.2024.178301

Air pollution clouds the mind and makes everyday tasks challenging, researchers discover

People's ability to interpret emotions or focus on performing a task is reduced by short-term exposure to particulate matter (PM) air pollution, potentially making everyday activities, such as the weekly supermarket shop, more challenging, a new study reveals.

Scientists discovered that even brief exposure to high concentrations of PM may impair a person's ability to focus on tasks, avoid distractions, and behave in a socially acceptable manner.

Researchers exposed study participants to either high levels of air pollution—using candle smoke—or clean air, testing cognitive abilities before and four hours after exposure. The tests measured working memory, selective attention, emotion recognition, psychomotor speed, and sustained attention.

Publishing their findings on 6 Feb in Nature Communications, researchers  reveal that selective attention and emotion recognition were negatively affected by air pollution—regardless of whether subjects breathed normally or only through their mouths.

The experts suggest that inflammation caused by pollution may be responsible for these deficits, noting that while selective attention and emotion recognition were affected, working memory was not. This indicates that some brain functions are more resilient to short-term pollution exposure.

 Acute particulate matter exposure diminishes executive cognitive functioning after four hours regardless of inhalation pathway, Nature Communications (2025).

Mercury content in tuna can be reduced with new packaging solution

According to the World Health Organization (WHO), mercury is one of the ten most harmful chemicals for humans. Exposure can damage the central nervous system, with fetuses and young children being particularly sensitive to the effects. That is why dietary recommendations for pregnant women advise caution with tuna consumption.

Fish is a high-quality source of protein, containing omega-3 fatty acids and many other beneficial nutrients. However, the accumulation of toxic mercury also makes fish consumption a concern, of which tuna is particularly susceptible.

Researchers have come up with a novel approach to packaging canned tuna infused in a water-based solution of amino acid cysteine. It was shown to remove up to 35% of the accumulated mercury in canned tuna, significantly reducing human exposure to mercury via food. The research is published in the journal Global Challenges.

The concept of so-called active packaging is to develop materials, like a liquid inside a can, that interacts with food during storage to increase the shelf life.

This study shows that there are alternative approaches to addressing mercury contamination in tuna, rather than just limiting consumption. 

In the study, the researchers discovered that the greater the surface area of fish flesh in contact with the cysteine solution, the higher the mercury uptake. The highest value of mercury reduction, 35%, was reached when testing canned minced tuna, from regular grocery stores. They also discovered a maximum threshold of two weeks, after which no further changes occurred.

In the current study, however, the researchers did not observe any noticeable changes in appearance or smell of the tested fish samples. Cell-based assays have also proven the safety of the developed technology.

Przemysław Strachowski et al, New Insight into Mercury Removal from Fish Meat Using a Single‐Component Solution Containing cysteine, Global Challenges (2024). DOI: 10.1002/gch2.202400161

Scientists discover brain mechanism that helps overcome fear

Researchers have unveiled the precise brain mechanisms that enable animals to overcome instinctive fears. Published in Science, the study in mice could have implications for developing therapeutics for fear-related disorders such as phobias, anxiety and post-traumatic stress disorder (PTSD).

The researchers mapped out how the brain learns to suppress responses to perceived threats that prove harmless over time.

Humans are born with instinctive fear reactions, such as responses to loud noises or fast-approaching objects. However, we can override these instinctive responses through experience—like children learning to enjoy fireworks rather than fear their loud bangs. Scientists are trying  to understand the brain mechanisms that underlie such forms of learning.

Using an innovative experimental approach, the research team studied mice presented with an overhead expanding shadow that mimicked an approaching aerial predator. Initially, the mice sought shelter when encountering this visual threat.

However, with repeated exposure and no actual danger, the mice learned to remain calm instead of escaping, providing researchers with a model to study the suppression of fear responses.

Based on previous work , the team knew that an area of the brain called the ventrolateral geniculate nucleus (vLGN) could suppress fear reactions when active and was able to track knowledge of previous experience of threat. The vLGN also receives strong input from visual areas in the cerebral cortex, and so the researchers explored whether this neural pathway had a role in learning not to fear a visual threat.

The study revealed two key components in this learning process: 1) specific regions of the visual cortex proved essential for the learning process, and 2) a brain structure called the ventrolateral geniculate nucleus (vLGN) stores these learning-induced memories.

found that animals failed to learn to suppress their fear responses when specific cortical visual areas were inactivated. However, once the animals had already learned to stop escaping, the cerebral cortex was no longer necessary.

The new results challenge traditional views about learning and memory.

Part 1

While the cerebral cortex has long been considered the brain's primary center for learning, memory and behavioral flexibility, we found the subcortical vLGN and not the visual cortex actually stores these crucial memories. This neural pathway can provide a link between cognitive neocortical processes and 'hard-wired' brainstem-mediated behaviors, enabling animals to adapt instinctive behaviors.
The researchers also uncovered the cellular and molecular mechanisms behind this process. Learning occurs through increased neural activity in specific vLGN neurons, triggered by the release of endocannabinoids—brain-internal messenger molecules known to regulate mood and memory.

This release decreases inhibitory input to vLGN neurons, resulting in heightened activity in this brain area when the visual threat stimulus is encountered, which suppresses fear responses.
The implications of this discovery extend beyond the laboratory.
These findings could also help advance our understanding of what is going wrong in the brain when fear response regulation is impaired in conditions such as phobias, anxiety and PTSD. While instinctive fear reactions to predators may be less relevant for modern humans, the brain pathway we discovered exists in humans too.

This could open new avenues for treating fear disorders by targeting vLGN circuits or localized endocannabinoid systems.

Sara Mederos et al, Overwriting an instinct: Visual cortex instructs learning to suppress fear responses, Science (2025). DOI: 10.1126/science.adr2247. www.science.org/doi/10.1126/science.adr2247

Part 2

Why some heavy drinkers develop advanced liver disease, while others do not

Why do some people who consume a few glasses of alcohol a day develop advanced liver disease while others who drink the same amount don't? The answer may lie in three common underlying medical conditions, according to a new study published in Clinical Gastroenterology and Hepatology from Keck Medicine of USC. The research found that heavy drinkers with either diabetes, high blood pressure or a high waist circumference are as much as 2.4 times more likely to develop advanced liver disease.

The results identify a very high-risk segment of the population prone to liver disease and suggest that preexisting health issues may have a large impact on how alcohol affects the liver.

Diabetes, high blood pressure and a high waist circumference (35 inches for women; 40 inches for men), which is associated with obesity, belong to a cluster of five health conditions that influence an individual's risk for heart attack and stroke known as cardiometabolic risk factors.

Cardiometabolic risk factors have been linked to the buildup of fat in the liver (also known as metabolic dysfunction-associated steatotic liver disease), which can lead to fibrosis, or scarring of the liver.

Alcohol also causes fat buildup in the liver.

Researchers discovered that heavy drinkers with either diabetes or a high waist circumference were 2.4 times more likely to develop advanced liver disease and those with high blood pressure 1.8 times more likely.

They found that the other two cardiometabolic risk factors—high triglycerides (elevated levels of a type of fat in the blood) and low HDL (high-density lipoprotein or "good" cholesterol) had less significant correlations to liver disease.

 Brian P. Lee et al, Association of Alcohol and Incremental Cardiometabolic Risk Factors with Liver Disease: A National Cross-Sectional Study, Clinical Gastroenterology and Hepatology (2025). DOI: 10.1016/j.cgh.2025.01.003

Toxic dangers lurk in LA, even in homes that didn’t burn

Houses still standing after the LA fires may release dangerous chemicals indoors for months.

Even as firefighters douse the deadly LA wildfires, a more insidious danger remains. Chemicals from the ashy residue of thousands of burned homes and cars, scorched plastic pipes and even lifesaving fire retardants have blanketed parts of the region.

And that may jeopardize the immediate health of people living near burn zones for months to come. Long-term health consequences are also possible.

Wildfires’ aftermath may expose people to toxic chemicals and harmful particles in the air and water both outside and inside their homes, experts warn.

Ash, soot and other pollutants that settle out of smoke may get stirred up and resuspended by wind and as people move about. These emissions are not necessarily captured by the regional air quality monitoring.

So even if your city’s air “looks good or healthy or green, that doesn’t necessarily indicate that the air quality is good around your home.” That’s especially a problem for those living close to burned areas but may be an issue kilometers away, too.

Part 1

Exactly what may be in the air depends on the fuels that fed the fire. Smoke from burning vegetation is full of fine particles and chemicals, including ozone, sulfur dioxide, polycyclic aromatic hydrocarbons and other volatile compounds that can be hazardous to health.

Increasingly, urban areas are burning too, especially as development snuggles up next to wildlands. So heavy metals are another health worry.

Urban wildfires represent a unique challenge because of the types of pollutants that are generated.
When buildings and automobiles burn, heavy metals, such as lead and copper, get dispersed. Older homes may release asbestos fibers. Plastics and electronics give off noxious chemicals and metals. All of that can contaminate air, soil and water.
Some worry that the chemicals used to fight the fire pose a risk, too. Among the many iconic images of the LA fires were low-flying planes dumping fire retardants that painted neighborhoods red.
But the main component of fire retardant “is ammonium phosphate, which is basically just fertilizer,” say the experts. “The red color comes from iron oxide, which is more or less rust.” Gum or other thickeners may be added. Those are “not so harmful,” they say.

Source: https://www.sciencenews.org/article/toxic-danger-lurk-burn-los-ange...

Part 2

Common bacterial infection may trigger lung transplant rejection

A large team of surgeons and organ transplant researchers affiliated with multiple institutions  has found an association between lung transplant patients who become infected with the bacteria Pseudomonas aeruginosa and rejection of the transplanted lung.

In their study published in the journal Science Translational Medicine, the group analyzed lung transplant case histories looking for patients with P. aeruginosa and lung rejection.  Other researchers have published a Focus piece in the same journal issue outlining the work.

The relief that patients with sick lungs experience after a lung transplant is often quickly displaced by fear of their body rejecting the new lungs despite immunosuppressive drugs. Lung transplantation has one of the lowest rates of success of all organ transplants. One of the team members noticed that many patients who experienced lung rejection also had a P. aeruginosa infection.

The team wondered if such infections played a role in transplant rejections. To find out, they analyzed patient case histories and found the rate to be higher than expected. This prompted them to conduct experiments with lab mice.

In their lab experiments, otherwise healthy lab mice were infected with P. aeruginosa and were then given new lungs from another mouse. As the team monitored their progress, they found that the test mice infected with P. aeruginosa experienced bacterial spread to lymphoid tissue, where the infection killed CD4+ cells. That led to growth in the number of B cells expressing a protein called CXCR3, which were sensitive to antigens in the donated lungs. As a result, the B cells produced donor-specific antibodies, which led to rejection of the lungs.

The team also found that giving the test mice drugs that blocked the expression of CXCR3 by the B cells inhibited the mechanism that led to rejection, allowing the mice to keep their new lungs. Thus, the team not only found a possible association between P. aeruginosa infections and rejection of transplanted lungs, but a possible solution for the problem.

Fuyi Liao et al, Pseudomonas aeruginosa infection induces intragraft lymphocytotoxicity that triggers lung transplant antibody-mediated rejection, Science Translational Medicine (2025). DOI: 10.1126/scitranslmed.adp1349

Idaira M. Guerrero-Fonseca et al, No tolerance for Pseudomonas in lung transplants, Science Translational Medicine (2025). DOI: 10.1126/scitranslmed.adu6563

Evidence of cannibalism by ancient Magdalenian people found in cave in Poland

A team of archaeologists, paleontologists, and historians from several institutions in Spain, Germany, and Poland, has found evidence of Magdalenian people from approximately 18,000 years ago, living in a cave in what is now Poland, engaging in cannibalism. In their paper published in Scientific Reports, the group describes their analysis of bones found in the cave many years ago, and the evidence that strongly suggests that the early people were consuming human flesh.

Prior research has shown that multiple groups or entire cultures have at times throughout human history engaged in cannibalism. The practice has most often been performed as part of a ritual of some sort, although there are also many examples of people resorting to eating the remains of others in their group due to starvation conditions.

For this new study, the researchers took a new look at bones and bone fragments that had been removed from Maszycka Cave in southern Poland from digs that took place in the 19th century and as recently as the 1960s. Because the bones had been broken and splintered, it was not known until now that they were even of human origin.

In taking a close look at some of the fragments, the researchers noted there were marks on them consistent with marks on bones from animals that had been cut up and consumed. They also found that many of the bones had been cracked open so that the nutrient-rich marrow inside could be removed, and perhaps also consumed. They also note that the human bones were mixed in among bone fragments of other animals which had the same types of cut marks on them, suggesting they too were consumed.

The final piece of evidence was the timing; all the bones were from roughly the same time period, suggesting that they had been entombed together, possibly during a single event. Also, the bones are from a time not long after the last ice age—as more land opened up with the receding ice, cannibalism may have reflected the violence of competing for territory.

The research team suggests that taken together, the evidence strongly suggests cannibalism, though they acknowledge there is a little wiggle room. Some early cultures have been known to strip the bones of their dead clean as a form of ritual or burial. They note it is possible the people who left the bones behind were doing something similar.

 Francesc Marginedas et al, New insights of cultural cannibalism amongst Magdalenian groups at Maszycka Cave, Poland, Scientific Reports (2025). DOI: 10.1038/s41598-025-86093-w

**

PRESS RELEASE sent to me by DST, Govt. of India to share online:

CSIR-NIIST develops technology for converting biomedical waste into soil additives

· Science & Technology Minister Jitendra Singh to launch the Research-based Point-of-Care Validation of technology at AIIMS New Delhi on Feb 10

New Delhi, Feb 08: Union Minister for Science and Technology Dr. Jitendra Singh will formally launch an automated biomedical waste conversion rig that can disinfect pathogenic biomedical waste such as blood, urine, sputum, and laboratory disposables, without the use of costly and energy-intensive incinerators, besides imparting a pleasant fragrance to these foul-smelling toxic waste.

The rig, christened as “Sṛjanam” and developed by CSIR-NIIST based at Thiruvananthapuram, will be installed and commissioned at a function at AIIMS, New Delhi on February 10.

The prototype equipment, with a daily capacity of 400 kg, can handle 10 kg degradable medical waste per day in the initial phase. The technology, once validated, will be ready for full-scale implementation after securing approval from competent authorities.

Through this technology, CSIR-NIIST (National Institute for Interdisciplinary Science and Technology) aims at an innovative and alternative solution for the safe, inexpensive and environment-friendly disposal of pathogenic biomedical waste.

The event will be attended by Dr. M Srinivas, Director, AIIMS New Delhi; Dr. (Mrs.) N Kalaiselvi, Secretary, DSIR & DG, CSIR; Shri Tanmay Kumar, Secretary, MoEFCC; Dr Rajiv Bahl, Secretary, DHR & DG, ICMR; and Dr. V K Paul, Member, NITI Aayog.

Dr. C Anandharamakrishnan, Director, CSIR-NIIST, will propose the vote of thanks.

The technology, developed by CSIR-NIIST, has been confirmed by expert third-parties for its antimicrobial action and non-toxic nature of the treated material. It can also disinfect laboratory disposables for direct recycling. Soil studies have confirmed that the treated biomedical waste is superior to organic fertilizers like vermicompost.

“With its potential to transform treated waste into value-added soil additives with minimal human intervention, our technology provides a safer solution for healthcare facilities, avoids the risk of spills and occupational exposure, and assists in preventing uncontrolled spread of infectious microbes,” said Dr. C Anandharamakrishnan.

India produces 743 tonnes of biomedical waste daily, according to the 2023 annual report of the Central Pollution Control Board (CPCB). It presents a significant challenge for proper management and disposal.

Improper segregation, open dumping, open burning, and inadequate incineration lead to severe health hazards, such as the release of harmful human carcinogens, particulate matter, and ash residues. Increased biomedical waste generation demands more transportation facilities, increasing the risk of accidents and spills. The WHO has also emphasized the importance of innovative and alternative protocols for pathogenic biomedical waste disposal.

Dr. C Anandharamakrishnan said the dumping of biomedical waste at any premise is prohibited by law. However, there have been several incidents of dumping the biomedical waste generated in one state across the borders of the neighbouring states.

Incineration is a costly energy-intensive strategy that forces the stakeholders to adopt simpler and cheaper, but sometimes illegal means, to dispose biomedical waste.

Earth's inner core is less solid than previously thought

The surface of the Earth's inner core may be changing, as shown by a new study by  scientists that detected structural changes near the planet's center, published in Nature Geoscience.

The changes of the inner core have long been a topic of debate for scientists. However, most research has been focused on assessing rotation.

Located 3,000 miles below the Earth's surface, the inner core is anchored by gravity within the molten liquid outer core. Until now, the inner core was widely thought of as a solid sphere.

But a study conducted recently showed a different picture.

The study utilized seismic waveform data—including 121 repeating earthquakes from 42 locations near Antarctica's South Sandwich Islands that occurred between 1991 and 2024—to give a glimpse of what takes place in the inner core.

As the researchers analyzed the waveforms from receiver-array stations located near Fairbanks, Alaska, and Yellowknife, Canada, one dataset of seismic waves from the latter station included uncharacteristic properties the team had never seen before.

 The new study indicates that the near surface of the inner core may undergo viscous deformation, changing its shape and shifting at the inner core's shallow boundary.

The clearest cause of the structural change is interaction between the inner and outer core. The molten outer core is widely known to be turbulent, but its turbulence had not been observed to disrupt its neighbour the inner core on a human timescale.

The discovery opens a door to reveal previously hidden dynamics deep within Earth's core, and may lead to better understanding of Earth's thermal and magnetic field.

John Vidale, Annual-scale variability in both the rotation rate and near surface of Earth's inner core, Nature Geoscience (2025). DOI: 10.1038/s41561-025-01642-2. www.nature.com/articles/s41561-025-01642-2

Potassium-enriched salt shows promise for cutting recurrent stroke risk in clinical trial

Potassium supplements in salt were associated with reduced rates of recurrent stroke and mortality in a large-scale cluster randomized clinical trial involving patients.

Findings come from a subgroup (stroke patients) analysis within the original Salt Substitute and Stroke Study (SSaSS), an international study conducted by researchers.

Stroke ranks among the top causes of death and disability in low- and middle income countries, and recurrent events remain a major concern. High sodium intake and low potassium intake are considered key risk factors.

The SSaSS trial involved 600 villages and 20,995 individuals in rural China. In the previous studies, researchers replaced participants' salt with a 75% salt, 25% potassium chloride substitute.

In the study, "Salt Substitution and Recurrent Stroke and Death: A Randomized Clinical Trial," published in JAMA Cardiology, the team analyzed data from 15,249 participants who had previously reported suffering from stroke.

Researchers used data from the original study, which monitored blood pressure, stroke recurrence, mortality, and safety outcomes, including hyperkalemia risk. Urinary sodium/potassium excretion was also tracked.

Over the study period, recurrent stroke was 14% lower in the 25% potassium substitute group compared with the regular salt group, the same as found in the original full cohort study.

Mean systolic blood pressure over follow-up was lower in the salt substitute group compared with controls. A total of 2,735 recurrent stroke events occurred, with 691 fatal and 2,044 nonfatal episodes.

Hemorrhagic stroke showed a 30% relative reduction, and stroke-related deaths decreased by 21%. No meaningful difference in hyperkalemia was observed between groups.

Findings indicate that salt reduction with 25% potassium is a safe, low-cost dietary intervention that can reduce stroke recurrence and mortality among stroke survivors. Researchers suggest broader implementation of salt substitutes, particularly in regions with high sodium intake and limited access to preventive health care.

Xiong Ding et al, Salt Substitution and Recurrent Stroke and Death, JAMA Cardiology (2025). DOI: 10.1001/jamacardio.2024.5417

Almost all nations miss UN deadline for new climate targets

Nearly all nations missed a UN deadline Monday to submit new targets for slashing carbon emissions, including major economies under pressure to show leadership following the US retreat on climate change.

Just 10 of nearly 200 countries required under the Paris Agreement to deliver fresh climate plans by February 10 did so on time, according to a UN database tracking the submissions.

Under the climate accord, each country is supposed to provide a steeper headline figure for cutting heat-trapping emissions by 2035, and a detailed blueprint for how to achieve this.

Global emissions have been rising but need to almost halve by the end of the decade to limit global warming to safer levels agreed under the Paris deal.

This latest round of national pledges are the most important policy documents of this century.

Yet just a handful of major polluters handed in upgraded targets on time, with China, India and the European Union the biggest names on a lengthy absentee list.

Most G20 economies were missing in action with the United States, Britain and Brazil—which is hosting this year's UN climate summit—the only exceptions.

There is no penalty for submitting late targets, formally titled nationally determined contributions (NDCs).

They are not legally binding but act as an accountability measure to ensure countries are taking climate change seriously and doing their fair share toward achieving the Paris goals.

The sluggish response will not ease fears of a possible backslide on climate action as leaders juggle Trump's return and other competing priorities from budget and security crises to electoral pressure.

Source: News Agencies

Helping Evolution: How humans unintentionally altered the skulls of pigs

Short snouts and a flat profile—within a span of 100 years, humans have significantly changed the shape of the skulls of German domestic pigs. According to a team of scientists , this is likely down to new breeding practices introduced at the beginning of the 20th century.

The researchers analyzed 3D scans of 135 skulls of wild boars and domestic pigs from the early 20th and 21st centuries. Surprisingly, the same effects can even be observed in species that were kept separately. Their findings have been published in the journal Royal Society Open Science.

Humans have been keeping pigs as livestock for several centuries. During this time, the animals have changed considerably. For example, they have become larger and have lost their black and brown bristles and darker skin tone.

The demand for pork in some countries increased significantly at the beginning of the 20th century and breeders were encouraged to optimize their animals. They needed them to grow quickly, provide good meat, and be fertile.

For the current study, researchers analyzed 135 skulls from three different breeds: Deutsches Edelschwein, Deutsches Landschwein—and wild boars, who acted as a control group. The skulls were either from the early 20th century or were only a few years old.

The two domestic pig breeds exhibited significant changes: The animals' snouts became significantly shorter and flatter, while the skulls of the more contemporary animals no longer had a slightly outwardly curved forehead. Researchers  didn't expect such pronounced differences to appear within a span of only 100 years.

Remarkably, both breeds of domestic pig underwent the same changes, despite being kept separately. "These changes occurred even though breeders did not select the animals specifically for their skull shape, as this trait was not important for breeding. Instead, the changes appear to be an unintended by-product of selecting the desired traits.

Another reason for the alterations could be related to changes in the animals' diet. Nutrition is known to influence the growth and development of animals. Today, pigs are mainly fed pellets that are high in protein. In contrast, the skulls of wild boars, who remain omnivores, have not undergone such changes.

The findings demonstrate how strongly humans can influence the evolution of animals.

Charles Darwin assumed that long periods of time—millions of years—are required for major changes to take place. This work is further proof that humans can greatly accelerate this process through selective breeding, say the researchers.

Creationists are you listening?

A. Haruda et al, Evolution under intensive industrial breeding: skull size and shape comparison between historic and modern pig lineages, Royal Society Open Science (2025). DOI: 10.1098/rsos.241039

Gut bacteria can alter brain proteins: New glycosylation method uncovers link

Our guts are home to trillions of bacteria, and research over the last few decades has established how essential they are to our physiology—in health and disease. A new study by researchers shows that gut bacteria can bring about profound molecular changes in one of our most critical organs—the brain.

The new study, published in the journal Nature Structural & Molecular Biology, is the first to show that bacteria living in the gut can influence how proteins in the brain are modified by carbohydrates—a process called glycosylation. The study was made possible by a new method the scientists developed—DQGlyco—which allows them to study glycosylation at a much higher scale and resolution than previous studies.

Proteins are the workhorses of our cells and their main building blocks. Sugars, or carbohydrates, on the other hand, are among the body's main sources of energy. However, the cell also uses sugars to chemically modify proteins, altering their functions. This is called glycosylation.

Glycosylation can affect how cells attach to each other (adhesion), how they move (motility), and even how they talk to one another (communication).

It is involved in the pathogenesis of several diseases, including cancer and neuronal disorders.

Part 1

However, glycosylation has traditionally been notoriously difficult to study. Only a small portion of proteins in the cell are glycosylated and concentrating enough of them in a sample for studying (a process called 'enriching') tends to be laborious, expensive, and time-consuming.
So far, it's not been possible to do such studies on a systematic scale, in a quantitative fashion, and with high reproducibility. These are the challenges the researchers managed to overcome with the new method.
DQGlyco uses easily available and low-cost laboratory materials, such as functionalized silica beads, to selectively enrich glycosylated proteins from biological samples, which can then be precisely identified and measured. Applying the method to brain tissue samples from mice, the researchers could identify over 150,000 glycosylated forms of proteins ('proteoforms'), an increase of over 25-fold compared to previous studies.

The quantitative nature of the new method means that researchers can compare and measure differences between samples from different tissues, cell lines, species etc. This also allows them to study the pattern of 'microheterogeneity'—the phenomenon where the same part of a protein can be modified by many (sometimes hundreds of) different sugar groups.

One of the most common examples of microheterogeneity is human blood groups, where the presence of different sugar groups on proteins in red blood cells determines blood type (A, B, O, and AB). This plays a major role in deciding the success of blood transfusions from one individual to the other.

The new method allowed the team to identify such microheterogeneity across hundreds of protein sites.
With this new weapon, teh researchers tackled the present problem.
The team found that when compared to "germ-free mice," i.e. mice grown in a sterile environment such that they completely lack any microbes in and on their body, mice colonized with different gut bacteria had different glycosylation patterns in the brain. The changed patterns were particularly apparent in proteins known to be important in neural functions, such as cognitive processing and axon growth.

The study's datasets are openly available via a new dedicated app for other researchers.

Clément M. Potel et al, Uncovering protein glycosylation dynamics and heterogeneity using deep quantitative glycoprofiling (DQGlyco), Nature Structural & Molecular Biology (2025). DOI: 10.1038/s41594-025-01485-w

Part 2

Students discover a new protein while investigating Streptococcus infection

Strep throat, something we've all had at some point in our lives, is caused by the bacteria Streptococcus pyogenes. Infection by Streptococcus can be fatal in serious cases and is the leading cause of death among flesh-eating diseases, resulting in over half a million deaths annually.

That scratchy, sore feeling at the back of your throat is a result of Streptococcus pyogenes infected by viruses called bacteriophages. These "phages" carry the genes for toxins that are responsible for strep throat, and when they invade Streptococcus pyogenes, they transfer these genes, enhancing the bacterium's ability to cause infection.

However, many people carry Streptococcus pyogenes on their bodies, and it doesn't make them sick. Some of the big questions in the field are when, how and why does it make you sick? And why does Streptococcus become a pathogen?

Two graduate students have discovered that phages use paratox to control the metabolism of Streptococcus, redirecting DNA processing pathways for the benefit of the phage.

With help from undergraduate student Julia Horne, the team was able to demonstrate that paratox also likely regulates when it is time for the phage to leave Streptococcus and go on to infect new bacteria. Muna and Horne now have a protein named after them, JM3 which stands for Julia Muna construct 3.

 This discovery, published in Nucleic Acids Research, has opened many doors for future research projects.

Tasneem Hassan Muna et al, The phage protein paratox is a multifunctional metabolic regulator of Streptococcus, Nucleic Acids Research (2024). DOI: 10.1093/nar/gkae1200

Less, but more: A new evolutionary scenario marked by massive gene loss and expansion

Evolution is traditionally associated with a process of increasing complexity and gaining new genes. However, the explosion of the genomic era shows that gene loss and simplification is a much more frequent process in the evolution of species than previously thought, and may favor new biological adaptations that facilitate the survival of living organisms.

This evolutionary driver, which seems counter-intuitive—"less is more" in genetic terms—now reveals a surprising dimension that responds to the new evolutionary concept of "less, but more," i.e., the phenomenon of massive gene losses followed by large expansions through gene duplications.

This is one of the main conclusions of an article published in the journal Molecular Biology and Evolution.

The paper identifies new evolutionary patterns, and it outlines a new scenario, marked by the enormous potential for genetic change and evolutionary adaptation driven by large-scale gene loss and duplication in living organisms.

Gene loss is a widespread mechanism throughout the biological scale and represents an evolutionary driving force that can generate genetic variability and also biological adaptations, and this has traditionally been known as the 'less is more' hypothesis.

Now, the paper describes a new evolutionary framework called "less, but more," which extends the previous model in terms of the importance of gene loss as an evolutionary driving force.

Part 1

This work focuses on the study of the genome of the Oikopleura dioica species, a swimming organism of the marine zooplankton that belongs to the tunicates—a sister group of vertebrates—and is phylogenetically linked to evolutionary history. In this study model—a free-living tunicate or appendicularian—the team reconstructed the evolutionary history of fibroblast growth factor (FGF) gene families, which are critical in the developmental process of organisms.

"The findings suggest that the process of gene loss reduced the number of FGF growth factor gene families from eight to just two, which are the Fgf9/16/20 and Fgf11/12/13/14 families. These surviving subfamilies have doubled over the course of evolution to generate a total of 10 genes in appendicularians.
The "less, but more" evolutionary model "helps us to understand how sometimes losing opens up new possibilities for subsequent gains and, therefore, losses are necessary to favor the evolutionary origin of new adaptations

Gaspar Sánchez-Serna et al, Less, but More: New Insights From Appendicularians on Chordate Fgf Evolution and the Divergence of Tunicate Lifestyles, Molecular Biology and Evolution (2024). DOI: 10.1093/molbev/msae260

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Part 2

Human presence at waterholes may change animal behavior

When tourists venture into nature, their thoughts are often focused on the animals they'll get to see. But animals may also have them in mind, according to a new study from the University of Georgia published in the Journal of Zoology.

With how common tourism is becoming, humans and animals will cross paths more often. Not only are tourists coming to watch the animals, but researchers will also stay out for long periods of time to count populations of different species.

As such, the study focused on how humans being nearby influenced the behavior of African mammals, including lions and zebras, while at waterholes.

When humans are present, some animals shift their daily activity patterns. the carnivores changed because of the human presence, and the herbivores changed because of the carnivore presence. It was not just one species that altered their behavior.

The study used a series of camera traps that took photos once animals walked by. Based on these pictures, researchers determined when and how often animals were visiting waterholes.

When humans were around, the time of day when some mammals came to the waterhole would shift compared to periods when humans weren't present. Some would visit earlier, while others visited later.

Animals shifting schedules can lead to different species interacting when they usually wouldn't—something that's especially a problem for some herbivores that could run into predators who typically aren't active during those times of the day.

Because of how important tourism is for conservation and income, the researchers emphasized the need to consider how human activity can impact animals on a larger scale.

Part 1 

Nocturnal carnivores became more active during the day
The study took place at the Ongava Research Center in Namibia, a country in Southern Africa. It is a nature reserve that borders a national park, where tourists have a heavy presence.
During the dry season, animals on the reserve depend on man-made waterholes. With so few sources of water, this gave researchers a reliable spot to set up camera traps and document animal activity.

Photos were taken three days before humans came, three days while they were at the waterholes and three days after they left. Researchers did this for two years.
Four major carnivore species—the spotted hyena, black-backed jackal, brown hyena and African lion—came to the waterhole more during the day. Usually, these predators rule the night, and are less active during the day.
Having humans at the waterholes at night, when they typically aren't there, maybe threw the animals off a bit and made them nervous, say teh researchers .
Since carnivores in the area already knew humans would be around during the day, they may have felt more comfortable getting water then instead of at night when tourists usually aren't at waterholes.
Predators and prey could cross paths more often
Some herbivores also changed their schedule. The duiker, springbok, mountain zebra and plains zebra started to visit the waterholes at night, despite being more comfortable around people.

This change was likely to avoid the carnivores that started visiting the waterhole during the day. But not all herbivores made the switch.

There are many other herbivore species that are still active during the day and overlap with those carnivores now.
That can change the dynamics of the ecosystem, and some animals could get preyed upon during times of the day when they usually feel safer.
Tourism still essential for wildlife conservation
Outside of shifting schedules, the presence of humans may be stressful for some animals.

Even so, tourism remains an essential tool for bringing attention and money to wildlife conversation, the researchers said. It also offers employment and a source of income to many people, especially in rural regions.

But it also takes a very pristine environment and brings people into it.
We must understand how tourism is affecting these eco systems to protect them efficiently.

J. R. Patterson et al, Effects of human presence on African mammal waterhole attendance and temporal activity patterns, Journal of Zoology (2024). DOI: 10.1111/jzo.13245

Part 2

Mitochondria's role in diabetes

Mitochondria are essential for generating energy that fuels cells and helps them function.

Mitochondrial defects, however, are associated with the development of diseases such as type 2 diabetes. Patients who suffer from this disorder are unable to produce enough insulin or use the insulin produced by their pancreas to keep their blood sugar at normal levels.

Several studies have shown that insulin-producing pancreatic β-cells of patients with diabetes have abnormal mitochondria and are unable to generate energy. Yet, these studies were unable to explain why the cells behaved this way.

In a study published in Science, researchers used mice to show that dysfunctional mitochondria trigger a response that affects the maturation and function of β-cells.

The researchers also confirmed their findings in human pancreatic islet cells.

Mitochondrial dysfunction affects several types of cells

Their results prompted the team to expand their search into other cells that are affected during diabetes.

Reversing mitochondrial damage could help cure diabetes

Regardless of the cell type, the researchers found that damage to the mitochondria did not cause cell death.

This observation brought up the possibility that if they could reverse the damage, the cells would function normally.

To do so, they used a drug called ISRIB that blocked the stress response. They found that after four weeks, the β-cells regained their ability to control glucose levels in mice.

Losing your β-cells is the most direct path to getting type 2 diabetes. Through this study we now have an explanation for what might be happening and how we can intervene and fix the root cause.

Emily M. Walker et al, Retrograde mitochondrial signaling governs the identity and maturity of metabolic tissues, Science (2025). DOI: 10.1126/science.adf2034

Crossing the blood–brain barrier with a payload via engineered bacteria

Researchers  have reported crossing the blood–brain barrier with help from a modified Lactobacillus plantarum. By delivering an appetite-regulating hormone directly to the olfactory epithelium, the hormone was able to reach its target.

Only the secreted hormone molecules crossed into the brain. Engineered Lactobacillus plantarum remained in the nasal passage, where it released its therapeutic payload, which then diffused along the olfactory pathway into the brain.

Current approaches to treating neurological conditions suffer from the highly protective nature of the blood–brain barrier. Intranasal therapies often encounter rapid clearance without a sustained therapeutic delivery.

In the study "Engineered Commensals for Targeted Nose-to-Brain Drug Delivery," published in Cell, researchers address these challenges by exploiting L. plantarum's natural affinity for the olfactory epithelium.
L. plantarum was chosen as a delivery vector as it naturally localizes to the olfactory epithelium binding sites. Initial investigations involved engineering L. plantarum to express and secrete hormones such as leptin, alpha-melanocyte-stimulating hormone and brain-derived neurotrophic factor (BDNF).

Experiments incorporated in vitro models using nasal cell monolayers and in vivo studies with male mice aged 6 to 8 weeks. Intranasal administration of fluorescent-labeled bacteria allowed visualization of bacterial localization.

Part 1

As expected, the engineered bacteria localized specifically in the olfactory epithelium and released their payloads into adjacent brain regions. Mice fed a high-fat diet and treated with hormone-secreting bacteria exhibited reduced body weight gain, lower food consumption, improved glucose tolerance and diminished adipose tissue deposition compared with control groups.

Findings further indicated that leptin secreted by the bacteria persisted in the olfactory epithelium longer than recombinant leptin delivered intranasally.

Results support the method's potential as a noninvasive vector for brain-targeted therapies. While the study used an appetite-regulating hormone, this delivery system could be adapted for neurological conditions such as Parkinson's disease, Alzheimer's, and brain cancers, where drug penetration into the brain remains a major hurdle.

Haosheng Shen et al, Engineered commensals for targeted nose-to-brain drug delivery, Cell (2025). DOI: 10.1016/j.cell.2025.01.017

Part 2

Why babies recover, but adults scar, after heart damage

Newborns with heart complications can rely on their newly developed immune systems to regenerate cardiac tissues, but adults aren't so lucky. After a heart attack, most adults struggle to regenerate healthy heart tissue, leading to scar-tissue buildup and, often, heart failure.

A new  study in experimental animals reveals a critical difference in how macrophages—a part of the immune system—help repair the heart in newborns versus adults after a heart attack. The study highlights a fundamental difference in how the immune system drives healing based on age.

The study is published in the journal Immunity.

In newborns, macrophages perform a process called efferocytosis, which recognizes and eats dying cells. This process triggers the production of a bioactive lipid called thromboxane, signaling nearby heart muscle cells to divide, and allowing the heart to regenerate damaged heart muscle, the study found. In adults, macrophages produce much less thromboxane, leading to a weaker repair signal.

"By mimicking the effects of thromboxane, we might one day improve tissue repair after a heart attack in adults," the researchers say.

Early Age Efferocytosis Directs Macrophage Arachidonic Acid Metabolism for Tissue Regeneration, Immunity (2025).

Study shows male stick insects have lost their reproductive function

While most animals reproduce sexually, some species rely solely on females for parthenogenetic reproduction. Even in these species, rare males occasionally appear. Whether these males retain reproductive functions is a key question in understanding the evolution of reproductive strategies.

A new study published in Ecology by a research team provides insight into this question. The researchers focused on the rare males of Ramulus mikado, a stick insect species in Japan, where parthenogenesis is predominant. Their analysis of male reproductive behavior reveals new findings.

Males engage in mating but do not contribute genetically. The rare males actively mated with females, just like typical males. However, genetic analysis confirmed that no male-derived genes were passed on to their offspring. The study further revealed that these males do not produce functional sperm, rendering them incapable of restoring sexual reproduction in the species.

Their findings showed that the males exhibited the typical morphological traits of stick insects and engaged in mating behaviors with conspecific females. However, despite their reproductive attempts, they were completely sterile. At the same time, the female reproductive organs associated with sexual reproduction showed signs of degeneration.

The rare males of this stick insect have completely lost their reproductive function.

Part 1

Unlike female sexual traits, the loss of male sexual traits is generally thought to take an extremely long time. In many other species, even rare males often retain their reproductive capabilities. However, these findings suggest that R. mikado has relied solely on parthenogenesis for such an extended period that even neutral mutations have accumulated, leading to the complete loss of male reproductive traits.
This study demonstrates that parthenogenesis in R. mikado has become irreversible. Although asexual reproduction is often considered evolutionarily short-lived due to the lack of genetic recombination, previous research estimated that this species has persisted for hundreds of thousands of years. How has R. mikado managed to survive for such a long time? This remains an intriguing mystery for future research.

Tomonari Nozaki et al, Lack of successful sexual reproduction suggests the irreversible parthenogenesis in a stick insect, Ecology (2025). DOI: 10.1002/ecy.4522

Part 2