Study Finds a Potential Downside to Vigorous Exercise

Tumour microbes contribute to resistance
A signalling molecule produced by bacteria in breast tumours can help the cancer resist certain treatments. The cancer drug trastuzumab blocks the action of a protein called HER2, which cancer cells use to grow. Pseudomonas aeruginosa — a bacterial species commonly found in breast tumours — produces a molecule called 3oc, mainly to kill immune cells. But researchers found that 3oc has an off-target effect: it activates a chemical pathway in breast cancer cells that triggers HER2 production, dampening the effect of trastuzumab.

A Bacterial Signaling Molecule Lends Tumors Drug Resistance

Aggressive breast cancer can become unresponsive to monoclonal antibody treatment, but targeting tumor-resident bacteria may extend its effectiveness.

https://www.the-scientist.com/a-bacterial-signaling-molecule-lends-...

https://www.pnas.org/doi/10.1073/pnas.2421710122

Astronomers have located the universe's 'missing' matter

A new landmark study has pinpointed the location of the universe's "missing" matter, and detected the most distant fast radio burst (FRB) on record. Using FRBs as a guide, astronomers at the Center for Astrophysics | Harvard & Smithsonian (CfA) and Caltech have shown that more than three-quarters of the universe's ordinary matter has been hiding in the thin gas between galaxies, marking a major step forward in understanding how matter interacts and behaves in the universe.

They've used the new data to make the first detailed measurement of ordinary matter distribution across the cosmic web. The research is published in the journal Nature Astronomy.

For decades, scientists have known that at least half of the universe's ordinary, or baryonic matter—composed primarily of protons—was unaccounted for. Previously, astronomers have used techniques including X-ray emission and ultraviolet observations of distant quasars to find hints of vast amounts of this missing mass in the form of very thin, warm gas in between galaxies. Because that matter exists as hot, low-density gas, it was largely invisible to most telescopes, leaving scientists to estimate but not confirm its amount or location.

Enter FRBs—brief, bright radio signals from distant galaxies that scientists only recently showed could measure baryonic matter in the universe, but until now could not find its location. In the new study, researchers analyzed 60 FRBs, ranging from ~11.74 million light years away—FRB20200120E in galaxy M81—to ~9.1 billion light years away—FRB 20230521B, the most distant FRB on record. This allowed them to pin down the missing matter to the space between galaxies, or the intergalactic medium (IGM).

 Thanks to FRBs, we now know that three-quarters of it is floating between galaxies in the cosmic web. In other words, scientists now know the home address of the "missing" matter.

By measuring how much each FRB signal was slowed down as it passed through space, researchers tracked the gas along its journey. They shine through the fog of the intergalactic medium, and by precisely measuring how the light slows down, we can weigh that fog, even when it's too faint to see.

The results were clear: Approximately 76% of the universe's baryonic matter lies in the IGM. About 15% resides in galaxy halos, and a small fraction is burrowed in stars or amid cold galactic gas.

This distribution lines up with predictions from advanced cosmological simulations, but has never been directly confirmed until now.

This is a triumph of modern astronomy.

Liam Connor et al, A gas-rich cosmic web revealed by the partitioning of the missing baryons, Nature Astronomy (2025). DOI: 10.1038/s41550-025-02566-y

First artificial solar eclipses created by two European satellites

A pair of European satellites have created the first artificial solar eclipses by flying in precise and fancy formation, providing hours of on-demand totality for scientists.

The European Space Agency released the eclipse pictures at the Paris Air Show this week. Launched late last year, the orbiting duo have churned out simulated solar eclipses since March while zooming tens of thousands of miles (kilometers) above Earth.

Flying 492 feet (150 meters) apart, one satellite blocks the sun like the moon does during a natural total solar eclipse as the other aims its telescope at the corona, the sun's outer atmosphere that forms a crown or halo of light.

It's an intricate, prolonged dance requiring extreme precision by the cube-shaped spacecraft, less than 5 feet (1.5 meters) in size. Their flying accuracy needs to be within a mere millimeter, the thickness of a fingernail. This meticulous positioning is achieved autonomously through GPS navigation, star trackers, lasers and radio links.

Dubbed Proba-3, the $210 million mission has generated 10 successful solar eclipses so far during the ongoing checkout phase. The longest eclipse lasted five hours.

Scientists already are thrilled by the preliminary results that show the corona without the need for any special image processing.

Source: ESA

Seeing clearly through thick fog: Researchers develop ultra-low noise, high sensitivity photodetector

Technologies enabling safe visual recognition in low-visibility environments are gaining increasing attention across sectors such as autonomous driving, aviation, and smart transportation. Thick fog remains a major challenge on highways, mountainous roads, and airport runways, where vision-based recognition systems frequently fail.

Traditional visible light cameras, LiDAR, and thermal infrared (IR) sensors experience a sharp drop in signal-to-noise ratio(SNR) under scattering conditions, making object and pedestrian detection unreliable. To overcome these challenges, researchers are seeking near-infrared (NIR) sensors that can operate stably and with low noise in real-world conditions.

A research team  has developed a high-sensitivity organic photodetector (OPD) that maintains ultra-low noise performance even in light-scattering environments.

The study is published in the journal Advanced Materials.

The team successfully reconstructed transmission images in simulated fog and smoke conditions and quantitatively verified the sensor's performance.

The study is notable as it presents the first experimental demonstration of a hardware-based visibility enhancement system in realistic fog-like environments—following the team's earlier development of an AI-based software fog removal technology that received a CES 2025 Innovation Award.

Based on this achievement, the team is advancing a software-hardware integrated solution for visibility enhancement, targeting applications in autonomous driving, smart transportation infrastructure, and drone-based surveillance.

A core innovation of the OPD lies in a self-assembled monolayer electronic blocking layer developed by the team, called 3PAFCN.

This layer, characterized by a deep HOMO energy level and high surface energy, effectively suppresses dark current and reduces interfacial charge traps, thereby enhancing device stability and responsiveness.

Through this structural innovation, the OPD achieved a low noise current of 2.18 fA, along with the highest detectivity reported among NIR OPDs of its kind—surpassing the performance of commercial silicon-based photodetectors and indicating strong commercialization potential.

The team also constructed a laboratory environment simulating real fog, where they conducted single-pixel imaging experiments using the new OPD. Even under low-light conditions where visible-spectrum sensors failed to detect targets, the OPD successfully captured optical signals and reconstructed object shapes.

Seunghyun Oh et al, Robust Imaging through Light‐Scattering Barriers via Energetically Modulated Multispectral Organic Photodetectors, Advanced Materials (2025). DOI: 10.1002/adma.202503868

Artificial light in big cities is extending the growing season of urban plants

Artificial light may be lengthening the growing season in urban environments by as much as 3 weeks compared to rural areas, according to an analysis of satellite data from 428 urban centers in the Northern Hemisphere over 7 years, published in Nature Cities.

Rapid urbanization is leading to hotter and brighter cities. More specifically, buildings and concrete absorb and radiate heat, causing urban heat islands, in which urban areas have higher atmospheric temperatures throughout the day and night compared to their surroundings. Likewise, the amount of artificial light at night has increased by 10% in cities within the past decade.

Light and temperature also largely regulate plant growing seasons. For example, increased lighting and temperature cause trees in cities to bud and flower earlier in the spring and change color later in the autumn than trees in rural surroundings.

Researchers analyzed satellite observations, taken between 2014 and 2020, of 428 cities in the Northern Hemisphere—including New York City, Paris, Toronto, and Beijing—and data on artificial light at night, near-surface air temperature and plant growing seasons.

They  found that the wattage of artificial light at night increases exponentially from rural areas towards urban centers. Meng and colleagues suggest that this increased amount of light appears to influence the start and end of urban growing seasons more than the increase of temperature from rural to urban areas.

They also found that the effect of artificial light is especially pronounced at the end of the growing season compared to its influence on the start. More specifically, the start of the growing season is an average of 12.6 days earlier than in rural surroundings and the end is 11.2 days later in the cities analyzed.

The authors suggest that the effect of artificial light on the growing season may be further complicated by the relatively recent general switch from high-pressure sodium lamps to LED lighting, which plants may be more responsive to.

Lvlv Wang et al, Artificial light at night outweighs temperature in lengthening urban growing seasons, Nature Cities (2025). DOI: 10.1038/s44284-025-00258-2

RNA has newly identified role: Repairing serious DNA damage to maintain the genome

Your DNA is continually damaged by sources both inside and outside your body. One especially severe form of damage called a double-strand break involves the severing of both strands of the DNA double helix.

Double-strand breaks are among the most difficult forms of DNA damage for cells to repair because they disrupt the continuity of DNA and leave no intact template to base new strands on. If mis-repaired, these breaks can lead to other mutations that make the genome unstable and increase the risk of many diseases, including cancer, neurodegeneration and immunodeficiency.

Cells primarily repair double-strand breaks by either rejoining the broken DNA ends or by using another DNA molecule as a template for repair. However, researchers discovered that RNA, a type of genetic material best known for its role in making proteins, surprisingly plays a key role in facilitating the repair of these harmful breaks.

These insights could not only pave the way for new treatment strategies for genetic disorders, cancer and neurodegenerative diseases, but also enhance gene-editing technologies.

https://www.nature.com/articles/s41467-024-51457-9

Light Squeezed Out of Darkness in  Quantum Simulation

A careful alignment of three powerful lasers could generate a mysterious fourth beam of light that is throttled out of the very darkness itself.

What sounds like occult forces at work has been confirmed by a simulation of the kinds of quantum effects we might expect to emerge from a vacuum when ultra-high electromagnetic fields meet.

What we think of as empty space is – on a quantum level – an ocean of possibility. Fields representing all kinds of physical interactions hum with the promise of particles we'd recognize as the foundations of light and the building blocks of matter itself. These virtual particles essentially pop into and out of existence in fractions of a second.

All it takes for them to manifest longer-term is the right kind of physical persuasion that discourages them from canceling one another out; the kind of persuasion a series of strong electromagnetic fields might provide when arranged in a suitable fashion.

Using nothing but photons to generate the necessary electromagnetic fields, it's hoped the light being scattered out of the darkness won't be hidden in a fog of other particles, finally proving once and for all that it is possible in physics to squeeze something out of nothing.

A team of researchers from the University of Oxford in the UK and the University of Lisbon in Portugal used a semi-classical equation solver to simulate quantum phenomena in real time and in three dimensions, testing predictions on what ought to occur when incredibly intense laser pulses combine in empty space.

Waste can turn to rock within decades
Industrial waste is turning into solid rock in as little as 35 years. Researchers analysed a cliff made up of millions of cubic metres of slag produced by now-defunct iron and steel foundries along a stretch of the English coast. A coin from 1934 and an aluminium can tab manufactured after 1989 were embedded in the material, showing that it had lithified — essentially turning into rock — within that period. “All the activity we’re undertaking at the Earth’s surface will eventually end up in the geological record as rock, but this process is happening with remarkable, unprecedented speed,” said study co-author John MacDonald.

Industrial waste can turn into rock in as little as 35 years, new research reveals, instead of the thousands or millions of years previously assumed. The finding challenges what scientists know about rock formation, revealing an entirely new "anthropoclastic rock cycle."

The scientists found that waste from seaside industrial plants turns into rock especially rapidly due to the ocean water and air, which activate minerals such as calcium and magnesium in the waste, or slag, cementing it together faster than natural sediments.

Researchers dubbed this newly discovered process the "rapid anthropoclastic rock cycle." The findings challenge long-standing theories about how rocks form and suggest industries have far less time to dispose of their waste properly than previously thought

https://pubs.geoscienceworld.org/gsa/geology/article-abstract/doi/1...

Industrial waste is turning into a new type of rock at 'unprecedented' speed, new study finds

https://www.livescience.com/planet-earth/geology/industrial-waste-i...

How chemical bonds are formed: Physicists observe energy flow in real time

For the first time, a research team  has tracked in real time how individual atoms combine to form a cluster and which processes are involved.

To achieve this, the researchers first isolated magnesium atoms using superfluid helium and then used a laser pulse to trigger the formation process. The researchers were able to observe this cluster formation and the involved energy transfer between individual atoms with a temporal resolution in the femtosecond range.

Normally, magnesium atoms instantaneously form tight bonds, which means that there is no defined starting configuration for observation of the bond-formation processes

The researchers have solved this problem, which often arises when observing chemical processes in real time, by conducting experiments with superfluid helium droplets. These droplets act like ultra-cold "nano-fridges" that isolate the individual magnesium atoms from each other at extremely low temperatures of 0.4 Kelvin (= -272.75 degrees Celsius or 0.4 degrees Celsius above absolute zero) at a distance of a millionth of a millimeter.

This configuration allowed them to initiate cluster formation with a laser pulse and track it precisely in real time.

The researchers observed the processes triggered by the laser pulse using photoelectron and photoion spectroscopy. While the magnesium atoms combined to form a cluster, they were ionized with a second laser pulse.

Researchers were able to reconstruct the processes involved in detail on the basis of the ions formed and electrons released.

A key discovery here is energy pooling. As they bind to each other, several magnesium atoms transfer the excitation energy received from the first laser pulse to a single atom in the cluster, so that it reaches a much higher energy state. This is the first time that energy pooling has been demonstrated with time resolution.

Michael Stadlhofer et al, Real-time tracking of energy flow in cluster formation, Communications Chemistry (2025). DOI: 10.1038/s42004-025-01563-6

Wildfires could be harming the oceans and disrupting their carbon storage

Wildfires pollute waterways and could affect their ability to sequester carbon, recent research shows.

When forests burn, they release ash, soil particles and chemicals into the environment. In a Science of The Total Environment study which analyzed water quality and wildfire data, researchers were able to link increases in the concentrations of compounds like arsenic and lead, as well as nutrients such as nitrogen and phosphorus, to fires which had burned within the river's basin months prior.

Using monitoring data collected by Environment Canada over the last 20 years, they calculated that up to 16.3% of the variation in water quality could be attributed to wildfires. 

Black carbon is formed when fires burn the carbon in trees. Black carbon cycles very slowly in the environment, especially the particulate form, and may sequester carbon from the atmosphere when it is buried in the ocean.

In a study earlier in 2025, researchers found that there is an important seasonal aspect to this. Most of the water in the northern rivers currently comes from snowmelt, but with climate change, this could shift to being more rain-driven in the future.

This change could lead to more rapidly degradable dissolved black carbon being exported to the ocean, which means that this carbon sequestration may lessen in the future and black carbon could become an additional source of carbon dioxide to the atmosphere.

Emily Brown et al, Cumulative effects of fire in the Fraser River basin on freshwater quality and implications for the Salish Sea, Science of The Total Environment (2025). DOI: 10.1016/j.scitotenv.2025.179416

**

Websites are tracking you via browser fingerprinting, researchers show

Clearing your cookies is not enough to protect your privacy online. New research  has found that websites are covertly using browser fingerprinting—a method to uniquely identify a web browser—to track people across browser sessions and sites.

The findings are published as part of the Proceedings of the ACM on Web Conference 2025.

Fingerprinting has always been a concern in the privacy community, but until now, we had no hard proof that it was actually being used to track users.

When you visit a website, your browser shares a surprising amount of information, like your screen resolution, time zone, device model and more. When combined, these details create a "fingerprint" that's often unique to your browser. Unlike cookies—which users can delete or block—fingerprinting is much harder to detect or prevent. Most users have no idea it's happening, and even privacy-focused browsers struggle to fully block it.

It is like a digital signature you didn't know you were leaving behind. You may look anonymous, but your device or browser gives you away.

This research marks a turning point in how computer scientists understand the real-world use of browser fingerprinting by connecting it with the use of ads.

To investigate whether websites are using fingerprinting data to track people, the researchers had to go beyond simply scanning websites for the presence of fingerprinting code. They developed a measurement framework called FPTrace, which assesses fingerprinting-based user tracking by analyzing how ad systems respond to changes in browser fingerprints.

This approach is based on the insight that if browser fingerprinting influences tracking, altering fingerprints should affect advertiser bidding—where ad space is sold in real time based on the profile of the person viewing the website—and HTTP records—records of communication between a server and a browser.

This kind of analysis lets the researchers go beyond the surface. They were  able to detect not just the presence of fingerprinting, but whether it was being used to identify and target users—which is much harder to prove.

Part 1

The researchers found that tracking occurred even when users cleared or deleted cookies. The results showed notable differences in bid values and a decrease in HTTP records and syncing events when fingerprints were changed, suggesting an impact on targeting and tracking.

Additionally, some of these sites linked fingerprinting behavior to backend bidding processes—meaning fingerprint-based profiles were being used in real time, likely to tailor responses to users or pass along identifiers to third parties.

Perhaps more concerning, the researchers found that even users who explicitly opt out of tracking under privacy laws like Europe's General Data Protection Regulation (GDPR) and California's California Consumer Privacy Act (CCPA) may still be silently tracked across the web through browser fingerprinting.

Based on the results of this study, the researchers argue that current privacy tools and policies are not doing enough. They call for stronger defenses in browsers and new regulatory attention to fingerprinting practices. They hope that their FPTrace framework can help regulators audit websites and providers who participate in such activities, especially without user consent.

Zengrui Liu et al, The First Early Evidence of the Use of Browser Fingerprinting for Online Tracking, Proceedings of the ACM on Web Conference 2025 (2025). DOI: 10.1145/3696410.3714548

Part 2

Before dispersing out of Africa, humans likely had to learn to thrive in diverse habitats

All non-Africans are known to have descended from a small group of people that ventured into Eurasia around 50,000 years ago. However, fossil evidence shows that there were numerous failed dispersals before this time that left no detectable traces in living people.

In a paper published in Nature, new evidence explains for the first time why those earlier migrations didn't succeed.

It was found that before expanding into Eurasia 50,000 years ago, humans began to exploit different habitat types in Africa in ways not seen before.

The results showed that the human niche began to expand significantly from 70,000 years ago, and that this expansion was driven by humans increasing their use of diverse habitat types, from forests to arid deserts.

Previous dispersals seem to have happened during particularly favorable windows of increased rainfall in the Saharo-Arabian desert belt, thus creating 'green corridors' for people to move into Eurasia. However, around 70,000–50,000 years ago, the easiest route out of Africa would have been more challenging than during previous periods, and yet this expansion was sizable and ultimately successful.

Part 1

The researchers showed that humans greatly increased the breadth of habitats they were able to exploit within Africa before the expansion out of the continent. This increase in the human niche may have been a result of positive feedback of greater contact and cultural exchange, allowing larger ranges and the breakdown of geographic barriers.

Unlike previous humans dispersing out of Africa, those human groups moving into Eurasia after approximately 60–50,000 years ago were equipped with a distinctive ecological flexibility as a result of coping with climatically challenging habitats. This likely provided a key mechanism for the adaptive success of our species beyond their African homeland.

 Emily Hallett, Major expansion in the human niche preceded out of Africa dispersal, Nature (2025). DOI: 10.1038/s41586-025-09154-0. www.nature.com/articles/s41586-025-09154-0

Part 2

Chemical profile of fecal samples can help predict mortality in critically ill patients

The gut microbiome and the metabolites it produces offer promising insight into disease severity in critically ill patients. In a collaborative effort, researchers developed the metabolic dysbiosis score (MDS), a novel biomarker index based on the levels of 13 key fecal metabolites—the chemical byproducts of digestion. The designed index can identify high-risk patients early and guide timely interventions that could save the lives of critically ill hospitalized patients.

According to the research article published in Science Advances, the team collected fecal specimens from 196 critically ill patients admitted to the medical intensive care unit (MICU) for non-COVID-19 respiratory shock or failure. They analyzed the samples by mapping the microbiome's composition using shotgun metagenomic sequencing and measuring the gut-derived metabolites with high-precision mass spectrometry. The MDS assigned based on the results helped identify MICU patients who are at a higher risk of 30-day mortality.

Experts have long observed that the complex ecosystem of microorganisms residing in our digestive tract plays a crucial role in maintaining overall health, and its dysbiosis or imbalance in this microbiota has been linked to a range of metabolic and chronic illnesses.

Several studies have investigated possible links between fecal microbiome diversity profiles and mortality in critically ill patients in search of a potentially treatable trait. They found that ICU stays can reduce microbiome diversity, allowing harmful species such as Enterococcus and Enterobacterales to dominate over beneficial bacteria that support healthy gut function. These imbalances are often associated with serious outcomes, including an increased risk of infection and death.

Short-chain fatty acids (SCFAs), bile acids, and tryptophan metabolites are key groups of metabolites produced by the gut microbiota. Admission to the ICU, particularly following antibiotic treatment, can cause significant disruptions in these metabolites, leading to fecal metabolic dysbiosis—a condition that may contribute to increased susceptibility to various diseases.

Upon scoring the fecal samples based on the MDS, researchers found that a high MDS (>7.5) increased the risk of 30-day mortality by a factor of 8.66 in critically ill patients. The researchers, however, found no independent association between traditional microbiome diversity profile (or Enterococcus abundance) and 30-day mortality.

The researchers noted that fecal metabolic dysbiosis may represent a treatable trait in critically ill patients, with the MDS serving as a potential biomarker to identify those who could benefit from targeted interventions to correct this imbalance and improve outcomes.

 Alexander P. de Porto et al, Fecal metabolite profiling identifies critically ill patients with increased 30-day mortality, Science Advances (2025). DOI: 10.1126/sciadv.adt1466

Acute and chronic pain are different

A new study reveals that when we experience short-term (acute) pain, the brain has a built‑in way to dial down pain signals—like pressing the brakes—to keep them from going into overdrive. But in long‑term (chronic) pain, this braking system fails, and the pain signals just keep firing. This discovery helps explain why some pain goes away while other pain lingers, and it opens the door to new treatments that could stop pain from becoming chronic in the first place.

In a study published in Science Advances, researchers reveal that our bodies respond to acute (short‑term) and chronic (long‑lasting) pain in surprisingly different ways at the cellular level. Their discovery sheds new light on how pain becomes chronic—and opens the door to better‑targeted treatments.

The team studied a small but crucial region in the brainstem called the medullary dorsal horn, home to neurons that act as a relay station for pain signals. These projection neurons help send pain messages from the body to the brain.

The scientists found that during acute inflammatory pain, these neurons actually dial down their own activity. This built‑in "braking system" helps limit the amount of pain‑related signals sent to the brain. Once the inflammation and pain subside, the neurons return to their normal state.

However, in chronic pain, this braking system fails. The neurons don't reduce their activity—in fact, they become more excitable and fire more signals, potentially contributing to the persistence of pain.

Using a combination of electrophysiology and computer modeling, the researchers identified a key mechanism: a specific potassium current known as the A‑type potassium current (IA). This current helps regulate the excitability of neurons.

In acute pain, IA increases—acting like a natural sedative for the pain pathways. But in chronic pain, this current doesn't ramp up, and the neurons become hyperactive. The absence of this regulation may be one of the biological switches that turns temporary pain into a long‑lasting condition.

This is the first time  the researchers have seen how the same neurons behave so differently in acute versus chronic pain. The fact that this natural 'calming' mechanism is missing in chronic pain suggests a new target for therapy. If we can find a way to restore or mimic that braking system, we might be able to prevent pain from becoming chronic.

Ben Title et al, Opposite regulation of medullary pain-related projection neuron excitability in acute and chronic pain, Science Advances (2025). DOI: 10.1126/sciadv.adr3467. www.science.org/doi/10.1126/sciadv.adr3467

Using psychology  to cheat you: Casino Lights Could Be Warping Your Brain to Take Risks, Scientists Warn

Casino lighting could be nudging gamblers to be more reckless with their money, according to a new study, which found a link between blue-enriched light and riskier gambling behaviour.

The extra blue light emitted by casino decor and LED screens seems to trigger certain switches in our brains, making us less sensitive to financial losses compared to gains of equal magnitude, researchers found.

 As gambling addiction continues to be a growing global problem – with 1.2 percent of the world's population thought to have a gambling disorder – the study offers some important insight into how risky behaviors might be encouraged or discouraged.

Researchers found that light with more blue wavelengths in it, which is frequently emitted by LED screens and casino lighting, could subtly influence how people perceive losses and gains. This raises questions about the role of lighting in environments like casinos or online gambling platforms.

In the research conducted, on average, the participants were significantly less loss-averse under blue-enriched light. Men were more likely to take risky bets than women, which fits in with previous research into how gambling differs between the sexes.

The researchers think circadian photoreception, which is our non-visual response to light, is playing a part here. The level of blue spectrum light may be activating specific eye cells connected to brain regions in charge of decision-making, emotional regulation, and processing risk versus reward scenarios.

Under bright, blue-heavy light such as that seen in casino machines, the $100 loss didn't appear to feel as bad, so people were more willing to take the risk.

If you open up a gambling website or head into a casino, you'll notice there's a lot of blue light going on – the opposite of the warmer light that you'll often find in bedroom lighting and sleep aids such as lamps. Under light with more blue wavelengths, people may be less able to accurately judge risk and reward due to a decreased cognitive sensitivity to loss.

That raises some questions around ethics and responsibility, according to the researchers. While encouraging risk taking might be good for the gambling business, it's not good for the patrons spending their cash.

https://www.nature.com/articles/s41598-025-97370-z

 But what makes our brains decide a smell is bad?

A new study from UF Health researchers reveals the mechanisms behind how your brain decides you dislike—even loathe—a smell. The findings are published in the journal Molecular Psychiatry.

Odors are powerful at driving emotions, and it's long been thought that the sense of smell is just as powerful, if not more powerful, at driving an emotional response as a picture, a song or any other sensory stimulus.

Researchers wanted to answer these questions. 

They  started off with the amygdala, a brain region that curates your emotional responses to sensory stimuli. Although all our senses (sound, sight, taste, touch and smell) interact with this small part of your brain, the olfactory system takes a more direct route to it.

Smells evoke strong, emotional memories, but the brain's smell centers are more closely connected with emotional centers like the amygdala.

In the study, researchers looked at mice, who share neurochemical similarities with people. They can learn about odors and categorize them as good or bad. After observing their behavior and analyzing brain activity, the team found two genetically unique brain cell types that allow odors to be assigned into a bucket of good feelings or bad feelings.

Initially, the team expected that one cell type would generate a positive emotion to an odor, and another would generate a negative emotion. Instead, the brain's cellular organization gives the cells the capability of doing either.

It can make an odor positive or negative to you. And it all depends upon where that cell type projects in your brain and how it engages with structures in your brain.

 Sarah E. Sniffen et al, Directing negative emotional states through parallel genetically-distinct basolateral amygdala pathways to ventral striatum subregions, Molecular Psychiatry (2025). DOI: 10.1038/s41380-025-03075-0

Using ChatGPT to write essays may be eroding critical thinking skills

A team of neurologists and AI specialists at MIT's Media Lab has led a study looking into the brain impacts of large language model (LLM) use among people who engage with them for study or work. They report evidence that the use of LLMs may lead to an erosion of critical thinking skills. In their study, posted on the arXiv preprint server, the researchers asked groups of volunteers to write essays while connected to EEG monitors.

Researchers recruited 54 volunteers. The initial group was then split into three small groups, all of whom were asked to write a 20-minute esay on the topic of philanthropy—one group was asked to use ChatGPT for help, the second was asked to use Google Search, and the third "Brain-only" group was given no tools or resources at all. The participants remained in these same groups for three writing sessions.

Each of the volunteers was fitted with an EEG device to monitor brain activity, such as cognitive engagement and mental workload, while they wrote. The researchers also performed natural language processing analysis and interviewed participants after each session. Essays were scored by human teachers as well as an AI agent.

For these first three sessions, the EEG analysis showed clear differences in brain connectivity between the groups. The Brain-only group showed the strongest and most widespread brain network activity, the search engine group showed intermediate levels of engagement, and the ChatGPT group showed the weakest overall brain connectivity.

Out of the 54 volunteers, 18 also returned months later to complete a fourth session. Those who had used ChatGPT now went the Brain-only route, and vice versa. In this session, those who had originally used ChatGPT in the first three sessions showed weaker neural connectivity, while those from the previous Brain-only group demonstrated higher memory recall.

Overall, the interviews also revealed that volunteers who used the LLM felt less ownership over their essays compared to the other groups. ChatGPT users also struggled to recall or quote from their own essays shortly after writing them. Across all measures—brain activity, language analysis, and essay scoring—participants who relied on ChatGPT performed worse than the Brain-only group.

These findings highlight the potential educational impact of relying on LLMs for writing tasks. While they can provide immediate benefits, they run the risk of reduced learning outcomes over time and frequent use may hinder the development of critical thinking skills.

Nataliya Kosmyna et al, Your Brain on ChatGPT: Accumulation of Cognitive Debt when Using an AI Assistant for Essay Writing Task, arXiv (2025). DOI: 10.48550/arxiv.2506.08872

Researchers turn toxic ancient tomb fungus into anti-cancer drug

Researchers have turned a deadly fungus into a potent cancer-fighting compound. After isolating a new class of molecules from Aspergillus flavus, a toxic crop fungus linked to deaths in the excavations of ancient tombs, the researchers modified the chemicals and tested them against leukemia cells. The result? A promising cancer-killing compound that rivals FDA-approved drugs and opens up new frontiers in the discovery of more fungal medicines.

Aspergillus flavus, named for its yellow spores, has long been a microbial villain. After archaeologists opened King Tutankhamun's tomb in the 1920s, a series of untimely deaths among the excavation team fueled rumors of a pharaoh's curse. Decades later, doctors theorized that fungal spores,

 dormant for millennia, could have played a role.

In the 1970s, a dozen scientists entered the tomb of Casimir IV in Poland. Within weeks, 10 of them died. Later investigations revealed the tomb contained A. flavus, whose toxins can lead to lung infections, especially in people with compromised immune systems.

Now, that same fungus is the unlikely source of a promising new cancer therapy.

The therapy in question is a class of ribosomally synthesized and post-translationally modified peptides, or RiPPs, pronounced like the "rip" in a piece of fabric. The name refers to how the compound is produced—by the ribosome, a tiny cellular structure that makes proteins—and the fact that it is modified later, in this case, to enhance its cancer-killing properties.

Part1

While thousands of RiPPs have been identified in bacteria, only a handful have been found in fungi. In part, this is because past researchers misidentified fungal RiPPs as non-ribosomal peptides and had little understanding of how fungi created the molecules.

The synthesis of these compounds is complicated. But that's also what gives them this remarkable bioactivity.
To find more fungal RiPPs, the researchers first scanned a dozen strains of Aspergillus, which previous research suggested might contain more of the chemicals.

By comparing chemicals produced by these strains with known RiPP building blocks, the researchers identified A. flavus as a promising candidate for further study.

Genetic analysis pointed to a particular protein in A. flavus as a source of fungal RiPPs. When the researchers turned the genes that create that protein off, the chemical markers indicating the presence of RiPPs also disappeared.

This novel approach—combining metabolic and genetic information—not only pinpointed the source of fungal RiPPs in A. flavus, but could be used to find more fungal RiPPs in the future.After purifying four different RiPPs, the researchers found the molecules shared a unique structure of interlocking rings. The researchers named these molecules, which have never been previously described, after the fungus in which they were found: asperigimycins.

Even with no modification, when mixed with human cancer cells, asperigimycins demonstrated medical potential: two of the four variants had potent effects against leukemia cells.
Another variant, to which the researchers added a lipid, or fatty molecule, that is also found in the royal jelly that nourishes developing bees, performed as well as cytarabine and daunorubicin, two FDA-approved drugs that have been used for decades to treat leukemia.
Through further experimentation, the researchers found that asperigimycins likely disrupt the process of cell division. Cancer cells divide uncontrollably. These compounds block the formation of microtubules, which are essential for cell division.
Notably, the compounds had little to no effect on breast, liver or lung cancer cells—or a range of bacteria and fungi—suggesting that asperigimycins' disruptive effects are specific to certain types of cells, a critical feature for any future medication.
In addition to demonstrating the medical potential of asperigimycins, the researchers identified similar clusters of genes in other fungi, suggesting that more fungal RiPPS remain to be discovered.

 A class of benzofuranoindoline-bearing heptacyclic fungal RiPPs with anticancer activities, Nature Chemical Biology (2025). DOI: 10.1038/s41589-025-01946-9

Part 2

Earth's satellites at risk if asteroid smashes into moon

If a huge asteroid smashes into the moon in 2032, the gigantic explosion would send debris streaming toward Earth that would threaten satellites and create a spectacular meteor shower, according to researchers.

It was given the highest chance—3.1%—of hitting our home planet that scientists have ever measured for such a giant space rock.

Subsequent observations from telescopes definitively ruled out a direct hit on Earth.

However, the odds that it will crash into the moon have risen to 4.3%, according to data from the James Webb Space Telescope in May.

A new preprint study, which has not been peer-reviewed, is the first to estimate how such a collision could affect Earth.

It would be the largest asteroid to hit the moon in around 5,000 years. The impact would be comparable to a large nuclear explosion in terms of the amount of energy released.

Up to 100 million kilograms (220 million pounds) of material would shoot out from the moon's surface, according to a series of simulations run by the researchers.

If the asteroid hit the side of the moon facing Earth—which is roughly a 50% chance—up to 10% of this debris could be pulled in by Earth's gravity over the following days, they said.

 These meteors could be capable of destroying some satellites—and there are expected to be a lot more of those orbiting the planet by 2032.

A centimeter-sized rock traveling at tens of thousands of meters per second is a lot like a bullet.

In the days after the impact, there could be more than 1,000 times the normal number of meteors threatening Earth's satellites.

Meanwhile, those of us on the ground would be treated to a "spectacular" meteor shower lighting up the night sky, the study said.

But the current odds of a direct hit on the near side of the moon remain at just two percent

The asteroid is not expected to be visible again until 2028, so the world will have to wait to find out more.

If a direct hit is eventually found to be likely, humanity probably has enough time to plan a mission to spare the moon.

The preprint study, which was published on the arXiv database last week, has been submitted to the Astrophysical Journal Letters.

Upcycling plastic into painkillers: Microbes transform everyday waste into acetaminophen

Paracetamol is traditionally made from dwindling supplies of fossil fuels including crude oil. Thousands of tons of fossil fuels are used annually to power the factories that produce the painkiller, alongside other medicines and chemicals—making a significant contribution to climate change, experts say.

The breakthrough addresses the urgent need to recycle a widely used plastic known as polyethylene terephthalate (PET), which ultimately ends up in landfill or polluting oceans. The strong, lightweight plastic is used for water bottles and food packaging, and creates more than 350 million tons of waste annually, causing serious environmental damage worldwide.

PET recycling is possible, but existing processes create products that continue to contribute to plastic pollution worldwide, researchers say.

Published in Nature Chemistry, a team of scientists from the University of Edinburgh's Wallace Lab used genetically reprogrammed E. coli, a harmless bacterium, to transform a molecule derived from PET known as terephthalic acid into the active ingredient of paracetamol.

Researchers used a fermentation process, similar to the one used in brewing beer, to accelerate the conversion from industrial PET waste into paracetamol in less than 24 hours.

The new technique was carried out at room temperature and created virtually no carbon emissions, proving that paracetamol can be produced sustainably. Further development is needed before it can be produced at commercial levels, the research team says.

Part 1

Some 90% of the product made from reacting terephthalic acid with genetically reprogrammed E. coli was paracetamol.

Experts say this new approach demonstrates how traditional chemistry can work with engineering biology to create living microbial factories capable of producing sustainable chemicals while also reducing waste, greenhouse gas emissions and reliance on fossil fuels.

Nick W. Johnson et al, A biocompatible Lossen rearrangement in Escherichia coli, Nature Chemistry (2025). DOI: 10.1038/s41557-025-01845-5

Part 2

Antimicrobial resistance genes hitch rides on imported seafood

Colistin is a potent, last-resort antibiotic used only to treat people with dangerous, life-threatening bacterial infections that have developed resistance to other drugs. But it's not foolproof. Worldwide, resistance to colistin is spreading, further diminishing treatment options and putting infected people at higher risk.

Researchers have identified a way that colistin  resistance genes are spreading: imported seafood.

In a new study, microbiologists  have reported the first isolation of colistin-resistance genes in bacteria found in imported shrimp and scallops, purchased from eight food markets around Atlanta, GA.

 Some countries do not have strict regulations for using antibiotics in food animal production, so imported food can be a vehicle for transmission of resistance,

The researchers presented the findings in Los Angeles at ASM Microbe 2025, the annual meeting of the American Society for Microbiology. An accompanying paper will be published in the journal mSphere.

**

Scientists find new blood type in Guadeloupe woman

A French woman from the Caribbean island of Guadeloupe has been identified as the only known carrier of a new blood type, dubbed "Gwada negative," France's blood supply agency has announced.

The announcement was made 15 years after researchers received a blood sample from a patient who was undergoing routine tests ahead of surgery, the French Blood Establishment (EFS) said on Friday.

"The EFS has just discovered the 48th blood group system in the world!" the agency said in a statement on social network LinkedIn.

"This discovery was officially recognized in early June in Milan by the International Society of Blood Transfusion (ISBT)."

The scientific association had until now recognized 47 blood group systems.

Thierry Peyrard, a medical biologist at the EFS involved in the discovery, told AFP that a "very unusual" antibody was first found in the patient in 2011.

Scientists were finally able to unravel the mystery in 2019 thanks to "high-throughput DNA sequencing," which highlighted a genetic mutation

The patient, who was 54 at the time and lived in Paris, was undergoing routine tests before surgery when the unknown antibody was detected.

She is the only person in the world who is compatible with herself

The woman inherited the blood type from her father and mother, who each had the mutated gene.

Recycled plastics can affect hormone systems and metabolism, study shows

A single pellet of recycled plastic can contain over 80 different chemicals. A new study by researchers shows that recycled polyethylene plastic can leach chemicals into water, causing impacts on the hormone systems and lipid metabolism of zebrafish larvae.

The work is published in the Journal of Hazardous Materials.

The plastic pollution crisis has reached global levels, threatening both planetary and human health, and recycling is proposed as one of the solutions to the plastics pollution crisis. However, as plastics contain thousands of chemical additives and other substances that can be toxic, and these are almost never declared, hazardous chemicals can indiscriminately end up in recycled products.

In a new study, researchers bought plastic pellets recycled from polyethylene plastic from different parts of the world and let the pellets soak in water for 48 hours. After which, zebrafish larvae were exposed to the water for five days. The experimental results show increases in gene expression relating to lipid metabolism, adipogenesis, and endocrine regulation in the larvae.

These short leaching times and exposure times are yet another indicator of the risks that chemicals in plastics pose to living organisms. The impacts that we measured show that these exposures have the potential to change the physiology and health of the fish.

Previous research has shown similar effects to humans, including threats to reproductive health and obesity, from exposure to toxic chemicals in plastics. Some chemicals used as additives in plastics and substances that contaminate plastics are known to disturb hormones, with potential impacts on fertility, child development, links to certain cancers, and metabolic disorders including obesity and diabetes.

Azora König Kardgar et al, Effects of leachates from black recycled polyethylene plastics on mRNA expression of genes involved in adipogenesis and endocrine pathways in zebrafish embryos, Journal of Hazardous Materials (2025). DOI: 10.1016/j.jhazmat.2025.138946

Tomatoes in the Galápagos are quietly de-evolving

On the younger, black-rock islands of the Galápagos archipelago, wild-growing tomatoes are doing something peculiar. They're shedding millions of years of evolution, reverting to a more primitive genetic state that resurrects ancient chemical defenses.

These tomatoes, which descended from South American ancestors likely brought over by birds, have quietly started making a toxic molecular cocktail that hasn't been seen in millions of years, one that resembles compounds found in eggplant, not the modern tomato.

In a study published recently in Nature Communications, scientists at the University of California, Riverside, describe this unexpected development as a possible case of "reverse evolution," a term that tends to be controversial among evolutionary biologists.

That's because evolution isn't supposed to have a rewind button. It's generally viewed as a one-way march toward adaptation, not a circular path back to traits once lost. While organisms sometimes re-acquire features similar to those of their ancestors, doing so through the exact same genetic pathways is rare and difficult to prove.

However, reversal is what these tomato plants appear to be doing.

The key players in this chemical reversal are alkaloids. Tomatoes, potatoes, eggplants, and other nightshades all make these bitter molecules that act like built-in pesticides, deterring insect predators, fungi, and grazing animals.

While the Galápagos are famous as a place where animals have few predators, the same is not necessarily true for plants. Thus, the need to produce the alkaloids.

What makes these Galápagos tomatoes interesting isn't just that they make alkaloids, but that they're making the wrong ones, or at least, ones that haven't been seen in tomatoes since their early evolutionary days.

Part 1

The researchers analyzed more than 30 tomato samples collected from distinct geographic locations across the islands. They found that plants on eastern islands produced the same alkaloids found in modern cultivated tomatoes. But on western islands, the tomatoes were churning out a different version with the molecular fingerprint of eggplant relatives from millions of years ago.

That difference comes down to stereochemistry, or how atoms are arranged in three-dimensional space. Two molecules can contain exactly the same atoms but behave entirely differently depending on how those atoms are arranged.

To figure out how the tomatoes made the switch, the researchers examined the enzymes that assemble these alkaloid molecules. They discovered that changing just four amino acids in a single enzyme was enough to flip the molecule's structure from modern to ancestral.
They proved it by synthesizing the genes coding for these enzymes in the lab and inserting them into tobacco plants, which promptly began producing the old compounds.

The pattern wasn't random. It aligned with geography. Tomatoes on the eastern, older islands, which are more stable and biologically diverse, made modern alkaloids. Those on the younger, western islands where the landscape is more barren and the soil is less developed, had adopted the older chemistry.

The researchers suspect the environment on the newer islands may be driving the reversal. It could be that the ancestral molecule provides better defense in the harsher western conditions.
To verify the direction of the change, the team did a kind of evolutionary modeling that uses modern DNA to infer the traits of long-extinct ancestors. The tomatoes on the younger islands matched what those early ancestors likely produced.

Still, calling this "reverse evolution" is bold. While the reappearance of old traits has been documented in snakes, fish, and even bacteria, it's rarely this clear, or this chemically precise.
And this kind of change might not be limited to plants. If it can happen in tomatoes, it could theoretically happen in other species, too.
It wouldn't happen in a year or two, but over time, maybe, if environmental conditions change enough.
And if you change just a few amino acids, you can get a completely different molecule. That knowledge could help us engineer new medicines, design better pest resistance, or even make less toxic produce.

Adam Jozwiak et al, Enzymatic twists evolved stereo-divergent alkaloids in the Solanaceae family, Nature Communications (2025). DOI: 10.1038/s41467-025-59290-4

Part 2

500 bird species face extinction within the next century, researchers warn

Climate change and habitat loss could cause more than 500 bird species to go extinct in the next 100 years, researchers  have found.

Their study, published in Nature Ecology & Evolution, reveals this number is three times higher than all bird extinctions recorded since 1500 CE. The extinction of vulnerable birds such as the bare-necked umbrellabird, the helmeted hornbill, and the yellow-bellied sunbird-asity would greatly reduce the variety of bird shapes and sizes worldwide, harming ecosystems that depend on unique birds like these for vital functions.

The scientists found that even with complete protection from human-caused threats like habitat loss, hunting and climate change, about 250 bird species could still die out.

Many birds are already so threatened that reducing human impacts alone won't save them. These species need special recovery programs, like breeding projects and habitat restoration, to survive.

We face a bird extinction crisis unprecedented in modern times. We need immediate action to reduce human threats across habitats and targeted rescue programs for the most unique and endangered species, the researchers say.

The researchers examined nearly 10,000 bird species using data from the IUCN Red List. They predicted extinction risk based on the threats each species faces. The study found that large-bodied birds are more vulnerable to hunting and climate change, while birds with broad wings suffer more from habitat loss.

This research also identified which conservation actions will best preserve both the number of bird species and their ecological functions.

Stopping the destruction of habitats would save the most birds overall. However, reducing hunting and preventing accidental deaths would save birds with more unusual features, which are especially important for ecosystem health.

Threat reduction must be coupled with targeted recovery programmes to conserve global bird diversity, Nature Ecology & Evolution (2025). DOI: 10.1038/s41559-025-02746-z

New evidence map shows normal use of plastic packaging contaminates food with micro- and nanoplastics

In an article published in npj Science of Food, scientists led by the Food Packaging Forum show that the normal and intended use of plastic food packaging and other food contact articles (FCAs), such as opening a plastic bottle or chopping on a plastic cutting board, can contaminate foodstuffs with micro- and nanoplastics (MNPs).

The article describes how the authors systematically evaluated 103 previously published studies investigating plastic particles less than 10 mm in foodstuffs or food simulants that had been in contact with an FCA made partly or entirely of plastic.

Food contact articles are a relevant source of MNPs in foodstuffs; however, their contribution to human MNP exposure is underappreciated, the researchers say.

 Food contact articles as source of micro- and nanoplastics: a systematic evidence map, npj Science of Food (2025). DOI: 10.1038/s41538-025-00470-3

Why AI and humans see objects differently: Meaning versus visual features

While humans concentrate on the meaning of objects, artificial intelligence focuses on visual characteristics.

These dimensions represent various properties of objects, ranging from purely visual aspects, like 'round' or 'white,' to more semantic properties, like 'animal-related' or 'fire-related,' with many dimensions containing both visual and semantic elements.

 While humans primarily focus on dimensions related to meaning—what an object is and what we know about it—AI models rely more heavily on dimensions capturing visual properties, such as the object's shape or color. Researchers call this phenomenon 'visual bias' in AI.

"Even when AI appears to recognize objects just as humans do, it often uses fundamentally different strategies. This difference matters because it means that AI systems, despite behaving similarly to humans, might think and make decisions in entirely different ways, affecting how much we can trust them.

 Florian P. Mahner et al, Dimensions underlying the representational alignment of deep neural networks with humans, Nature Machine Intelligence (2025). DOI: 10.1038/s42256-025-01041-7

Scientists use gene editing to correct harmful mitochondrial mutations in human cells

In a step toward treating mitochondrial diseases, researchers  have successfully edited harmful mutations in mitochondrial DNA using a genetic tool known as a base editor. The results, published in the open-access journal PLOS Biology, offer new hope for people with rare genetic conditions.

Mitochondria have their own small set of DNA. Mutations in this mitochondrial DNA can lead to a wide range of maternally inherited diseases, cancer, and aging-related conditions. While the development of CRISPR technology has given scientists new ways to correct mutations in nuclear DNA, this system cannot effectively cross the mitochondrial membrane and reach mitochondrial DNA.

In the new study, the researchers used a tool called a base editor—specifically, a DdCBE (double-stranded DNA deaminase toxin A-derived cytosine bas editor). This tool allows scientists to change a single letter in the DNA code without cutting it, and it works on mitochondrial DNA.

The team showed that they could effectively generate and correct mitochondrial DNA mutations in multiple disease-linked cell types in the lab. First, they engineered liver cells to carry a mitochondrial mutation that impairs energy production. Then they showed they could fix a different mutation in skin cells taken from a patient with the mitochondrial disorder Gitelman-like syndrome, restoring key signs of healthy mitochondrial function.

To help move the therapy toward clinical use, the researchers also tested the efficacy of delivering the mitochondrial base editors in mRNA form, rather than as DNA, and within lipid nanoparticles for delivery.

They showed that these approaches are more efficient and less toxic to cells than older methods like DNA plasmids. Importantly, the edits were highly specific, with minimal off-target changes detected in nuclear DNA and multiple detected in mitochondrial DNA.

Joore IP, et al. Correction of pathogenic mitochondrial DNA in patient-derived disease models using mitochondrial base editors. PLOS Biology (2025). DOI: 10.1371/journal.pbio.3003207

Sharks freeze when you turn them upside down

The freeze response—called "tonic immobility"—can be a lifesaver. Possums famously "play dead" to avoid predators. So do rabbits, lizards, snakes, and even some insects.

But what happens when a shark does it?

Researchers explored this strange behavior in sharks, rays and their relatives. In this group, tonic immobility is triggered when the animal is turned upside down—it stops moving, its muscles relax, and it enters a trance-like state. Some scientists even use tonic immobility as a technique to safely handle certain shark species. 

The reasons behind tonic immobility remain murky—especially in the ocean. It is generally thought of as an anti-predator defense. 

Three main hypotheses try to explain this immobility in sharks:

Anti-predator strategy—"playing dead" to avoid being eaten

Reproductive role—some male sharks invert females during mating, so perhaps tonic immobility helps reduce struggle

Sensory overload response—a kind of shutdown during extreme stimulation.

But research results don't support any of these explanations.

 So, scientists offer a simpler explanation. Tonic immobility in sharks is likely an evolutionary relic.

Evolutionary analysis suggests tonic immobility is "plesiomorphic"—an ancestral trait that was likely present in ancient sharks, rays and chimeras. But as species evolved, many lost the behavior.

Whatever may be the reason if you want to handle the sharks safely, just turn them upside down!

 Joel H. Gayford et al, Tonic immobility in cartilaginous fishes (Chondrichthyes): function, evolutionary history, and future directions, Reviews in Fish Biology and Fisheries (2025). DOI: 10.1007/s11160-025-09958-3

Droughts can reduce the caloric value of flower nectar by up to 95%

A study indicates that projected droughts by the end of this century could reduce the caloric value of flower nectar by up to 95%. This would harm pollinators, such as bees, as well as plants that depend on cross-pollination to reproduce and bear fruit, such as zucchini (Cucurbita pepo). In a less drastic scenario with a 30% reduction in rainfall, the drop was 34%.

In terms of calories potentially lost in the nectar, this is equivalent to more than a ton of sugar per hectare, from 1,325 to 71 kilos. Without nectar to consume, the bees leave, the plants don't reproduce, and the farmers lose production.

The work showed that an increase in rainfall positively affected an increase in nectar calories by 74%. However, the researchers point out the problems of heavier rainfall events in a wider ecological context.

A high frequency and intensity of rainfall can have devastating consequences for plants, flower visitors such as birds and insects, and the maintenance of interactions between plants and pollinators.

For example, the researchers cite the decrease in pollinator activity during rainy periods. Heavy rains make it difficult for pollinators to fly and regulate their body temperature, so they require more energy to search for food. Additionally, increased erosion and loss of nutrients affect crops.

Maria Luisa P. Frigero et al, Extreme events induced by climate change alter nectar offer to pollinators in cross pollination-dependent crops, Scientific Reports (2025). DOI: 10.1038/s41598-025-94565-2

Scientists discover unknown organelle inside our cells

The discovery of an unknown organelle inside our cells could open the door to new treatments for devastating inherited diseases.

The organelle, a type of specialized structure, has been dubbed a "hemifusome" by its discoverers. This little organelle has a big job helping our cells sort, recycle and discard important cargo within themselves, the scientists say. The new discovery could help scientists better understand what goes wrong in genetic conditions that disrupt these essential housekeeping functions.

Researchers think the hemifusome helps manage how cells package and process material, and when this goes wrong, it may contribute to diseases that affect many systems in the body.

 Amirrasoul Tavakoli et al, Hemifusomes and interacting proteolipid nanodroplets mediate multi-vesicular body formation, Nature Communications (2025). DOI: 10.1038/s41467-025-59887-9

Scientists detect deep Earth pulses beneath Africa

Research led by Earth scientists has uncovered evidence of rhythmic surges of molten mantle rock rising from deep within the Earth beneath Africa. These pulses are gradually tearing the continent apart and forming a new ocean.

The findings, published in Nature Geoscience, reveal that the Afar region in Ethiopia is underlain by a plume of hot mantle that pulses upward like a beating heart.

The team's discovery reveals how the upward flow of hot material from the deep mantle is strongly influenced by the tectonic plates—the massive solid slabs of Earth's crust—that ride above it.

Over millions of years, as tectonic plates are pulled apart at rift zones like Afar, they stretch and thin—almost like soft plasticine—until they rupture. This rupturing marks the birth of a new ocean basin.

 Mantle upwelling at Afar triple junction shaped by overriding plate dynamics, Nature Geoscience (2025). DOI: 10.1038/s41561-025-01717-0

Why most cats prefer to sleep on their left side?

An international research team that analyzed several hundred YouTube videos of sleeping cats found that they prefer to sleep on their left side. The researchers see this bias as an evolutionary advantage because it favors hunting and escape behavior after waking up.

All animals are particularly vulnerable while sleeping. Cats sleep around 12 to 16 hours a day, preferably in elevated places where their predators can only access them from below.

Researchers analyzed 408 publicly available YouTube videos in which a single cat was clearly visible with its entire body sleeping on one side for at least 10 seconds.

Two-thirds of the videos showed cats sleeping on their left side.

The explanation: Cats that sleep on their left side perceive their surroundings upon awakening with their left visual field, which is processed in the right hemisphere of the brain. This hemisphere is specialized in spatial awareness, the processing of threats and the coordination of rapid escape movements. If a cat sleeps on its left shoulder and wakes up, visual information about predators or prey goes directly to the right hemisphere of the brain, which is best in processing them. "Sleeping on the left side can therefore be a survival strategy," the researchers conclude.

Sevim Isparta et al, Lateralized sleeping positions in domestic cats, Current Biology (2025). DOI: 10.1016/j.cub.2025.04.043

Nitrate in drinking water linked to preterm birth rates

Even low levels of nitrate—a common agricultural runoff and drinking water contaminant—are associated with increased risks of preterm birth and low birthweight babies, according to a study published in PLOS Water.

Nitrate is a naturally occurring compound increasingly found in inorganic fertilizers and, through runoff, in groundwater. When consumed by humans, nitrates can interfere with the blood's capacity to carry oxygen.

After controlling for maternal and paternal characteristics as well as seasonal variation, the study found that early prenatal exposure to greater than 0.1 mg/L nitrate—just 1% of the current EPA limit—was associated with an increase in preterm birth (Est.=+0.66%-points; C.I.=0.31, 1.01) and early prenatal exposure to greater than 5 mg/L nitrate was associated with an increased risk of low birth weight babies (Est.=+0.33%-points; C.I.=0.03, 0.63). There were no additional risks conferred by exposure to elevated levels of nitrate, above 10 mg/L.

PLOS Water (2025). DOI: 10.1371/journal.pwat.0000329

How diverse brain cells reach a decision together

Every decision begins invisibly. Long before someone acts, the brain is already hard at work gathering evidence, weighing options, and gradually committing to a choice. But even when faced with the same evidence, people can arrive at different outcomes, especially when the decision is difficult.

How the brain, made up of billions of specialized cells, makes these split-second decisions has largely been a mystery, though.

Now, new findings  shed light on how diverse brain cells come together to guide a unified decision. The researchers found that while individual neurons have perplexingly complex responses, their activity is shaped by a shared structure that ultimately guides the brain toward a unified choice.

Though each neuron had a different individual response, they all appeared to share the same underlying potential landscape.

Think of it like a group of skiers descending a mountain. Each prefers a slightly different path, but all are shaped by the same slope beneath them. Similarly, each neuron has its own preference and activity, but the group of cells collectively in the premotor cortex takes a coordinated journey and gradually settles into a stable state that represents the decision, say the researchers.

Tatiana Engel, The dynamics and geometry of choice in the premotor cortex, Nature (2025). DOI: 10.1038/s41586-025-09199-1. www.nature.com/articles/s41586-025-09199-1

Global study links severe bleeding after childbirth to increased risk of cardiovascular disease

Women who experience severe bleeding after giving birth face elevated risks to their cardiovascular health that can persist for up to 15 years—a new analysis of data from over 9.7 million women across Europe, North America and Asia shows.

The findings, which follow a review of research data, some of which date back to 1986, suggest that women who experience postpartum hemorrhage (PPH) have an increased risk to both cardiovascular conditions—such as heart failure, stroke, and ischemic heart disease—and thromboembolic events, such as blood clots.

Published in The Journal of Maternal-Fetal & Neonatal Medicine, the results reveal these cardiovascular conditions are 1.76 times more likely, while thromboembolic incidents are 2.10 times more likely.

While this increased risk is particularly acute in the first year after giving birth, it can persist for up to 15 years, especially among women with complications that lead to high blood pressure during pregnancy, such as preeclampsia.

PPH has long been seen as an emergency that ends once the bleeding stops. But these new findings show it may have lasting effects on a woman's heart health, even years after childbirth.

Postpartum hemorrhage and long-term cardiovascular disease risk: a comprehensive systematic review and meta-analysis, The Journal of Maternal-Fetal & Neonatal Medicine (2025). DOI: 10.1080/14767058.2025.2507103

Cold drinks may trigger irregular heartbeat in some people with atrial fibrillation (Afib)

It may sound strange, but for some people, cold drinks may be to blame for sudden episodes of atrial fibrillation (Afib), a common heart rhythm disorder.

A recent survey sheds light on this phenomenon, dubbed "cold drink heart" (CDH). Researchers found that a surprising number of people with Afib report cold beverages as a trigger for their irregular heartbeats. In fact, for half of the survey participants who identified cold ingestion as an Afib trigger, avoiding cold drinks and foods completely eliminated their episodes. Others found relief by modifying their habits, such as letting drinks warm up, skipping the straw, or avoiding gulping.

Why might a cold drink send your heart out of rhythm?

While the exact mechanism isn't fully understood, it's likely related to the vagus nerve, which plays a role in regulating heart rate. The sudden temperature change from a cold drink might stimulate this nerve, leading to changes in heart rhythm in susceptible individuals, say experts.

It's important to remember that not everyone with Afib will experience this trigger. However, if you notice a connection between cold drinks and your Afib episodes, it's worth discussing with your doctor. Simple lifestyle changes, like avoiding very cold beverages or letting them warm up, could make a significant difference.

This doesn't replace the need for medical evaluation and treatment for Afib. If you experience any symptoms like heart palpitations, shortness of breath, or dizziness, seek medical attention promptly.

The survey, published in the Journal of Cardiovascular Electrophysiology, is the first to systematically explore the link between cold drinks and Afib. While more research is needed, the findings suggest that for some, a simple change in drinking habits could be a key to managing their condition.

Daniel D. DiLena et al, Characterizing Patients With Cold Drink‐Triggered Atrial Fibrillation, Journal of Cardiovascular Electrophysiology (2025). DOI: 10.1111/jce.16753

Synthetic protein jams up diseased cells
A synthetic ‘killswitch’ protein, just 17 amino acids long, can jam droplet-like structures that coordinate key cellular processes such as cancer, viral replication, gene expression and more. The droplet-like structures have no membranes and help to organize proteins and RNA molecules so that they can perform specific tasks efficiently and precisely. The killswitch infiltrates the droplets and fixes them in place. In a pair of experiments, researchers found that the killswitch could reduce leukaemia cell proliferation in mice and also curtail the production of viral particles in infected cells.

https://www.nature.com/articles/s41586-025-09141-5?utm_source=Live+...

Tech giants' net zero goals verging on fantasy: Researchers

The credibility of climate pledges by the world's tech giants to rapidly become carbon neutral is fading fast as they devour more and more energy in the race to develop AI and build data centers, researchers warned this week.

Apple, Google and Meta said they would stop adding CO₂ into the atmosphere by 2030, while Amazon set that target for 2040.

Microsoft promised to be "net negative"—pulling CO₂ out of the air—by the end of this decade.

But those vows, made before the AI boom transformed the sector, are starting to look like a fantasy even as these companies have doubled down on them, according to independent analysts.

"The greenhouse gas emissions targets of tech companies appear to have lost their meaning", the researchers say.

Source: News agencies

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Exercise sends 'mechanical messages' to cells, unlocking new energy pathways

Scientists  have made a breakthrough in understanding how cells in our body respond to physical activity and exercise.

Researchers discovered a direct mechanical signal that travels from outside the cell into the energy-producing parts of the cell, which could change the way we think about exercise and its benefits.

Researchers found a protein production factory in the cell, the endoplasmic reticulum, can sense external mechanical forces, such as stretching or strain and transmit them deep into the cell.

The process helps regulate energy production in the cell and maintains tissue health.

Cells constantly experience physical forces, especially in load-bearing tissues such as tendon, muscle and lung. Researchers found that the endoplasmic reticulum plays a central role in converting these mechanical cues into metabolic responses, controlling how cells produce energy and prevent tissue damage.

They discovered that while moderate physical activity and exercise could enhance energy production in cells, excessive strain or injury could disrupt this process, leading to cellular damage.

 Ziming Chen et al, External strain on the plasma membrane is relayed to the endoplasmic reticulum by membrane contact sites and alters cellular energetics, Science Advances (2025). DOI: 10.1126/sciadv.ads6132

Study shows sleeping brain remains alert to harsh, urgent sounds

During sleep, the brain must achieve a delicate balance: disconnecting from sensory input to allow restorative functions, while remaining alert enough to wake if danger arises. How does it sort through external stimuli—particularly sounds—during sleep? Scientists have studied how the brain responds to so-called "rough" sounds, such as screams or alarms.

They discovered that these sounds are systematically processed, unlike other sounds, triggering specific brain waves. These results, published in the journal Scientific Reports, provide a better understanding of certain perceptual disorders, such as hyperacusis (hypersensitivity and/or intolerance to certain sounds), as well as the impact of repeated nighttime disturbances on brain function.

Roughness is an acoustic property characterized by rapid modulations of sound intensity, between 40 and 100 times per second. Unlike speech, where syllables occur at a rate between 4 and 8 Hz, rough sounds hit the auditory system at much higher frequencies, producing a shrill and often unpleasant sensation.

This quality—typical of audible alarms, human screams and infant cries—is precisely what makes them so effective: They automatically capture our attention to signal imminent danger. These sounds directly activate the amygdala, a brain region involved in emotional responses and attention.

In the research conducted, the roughness—regardless of whether the sound was high- or low-pitched—that activated the brain's alert systems. The research team also observed two key phenomena. First, rough sounds consistently triggered a brain response, unlike other types of sounds. Second, sound roughness correlated with an increase in sleep spindles. These are short bursts of brain activity elicited in response to a sensory, and potentially disturbing, stimulus during sleep.

Sound roughness is not commonly encountered in everyday environments. In both humans and animals, it's typically reserved for urgent, high-stakes communication.

 Guillaume Y. T. Legendre et al, Scream's roughness grants privileged access to the brain during sleep, Scientific Reports (2025). DOI: 10.1038/s41598-025-01560-8

Scientists 3D-print part of human femur as strong as real bone

A group of  doctors and scientists printed part of a human femur—the longest and strongest bone in the body—that mimics the strength, flexibility and overall mechanics of a real femur. The findings were published in 2024 in a study in the Journal of Orthopaedic Research.

Recreating bones and organs like the heart or blood vessels is an emerging field. 3D-printed organs are far from replicating the functionality of a flesh-and-blood organ. 3D-printed bones, however, are being leveraged to various degrees.

 In scientific studies assessing how different forces stress and contort bone, these skeletal replicas offer scientists and physicians an accessible alternative to what is typically used: cadaver bones.

The printed bones  have the same strength or maybe even better strength than the human femur.

The 3D-printed bone is made with a low-cost biodegradable polymer called polylactic acid. In total, the bone costs about $7 to make, which is much cheaper than making other synthetic bones or obtaining cadaver bones.

Robert C. Weinschenk et al, Three‐dimensional‐printed femoral diaphysis for biomechanical testing—Optimization and validation, Journal of Orthopaedic Research (2024). DOI: 10.1002/jor.25954