Infections send protectors from gut to brain
Immune cells that fight stomach bugs can migrate from the gut to the brain, where they establish a lasting ‘memory’ of previous infection, according to a study in mice. After an infection, gut-trained T cells journey to the meninges, a protective membrane that shields the brain. Once there, the cells become residents that can respond to later infections. The findings could shed light on how gut infections might affect neurological disorders, and could help to develop therapies that harness the relationship between the gut and the central nervous system.

https://www.nature.com/articles/s41593-026-02428-4?utm_source=Live+...

https://www.nature.com/articles/d41586-026-02891-w?utm_source=Live+...

Scientists treat bleached corals with bacteria as oceans heat up

Coral reefs are under growing heat stress, but a new field test suggests researchers may have another tool to help them cope.

Coral probiotics succeed in real-world trial
One of the first real-world tests of coral probiotics shows that the treatment can help the organisms withstand a marine heatwave. Researchers found that treating heat-stressed Acropora cf. valida corals with a mixture of four or six bacterial strains isolated from healthy corals helped keep algae alive in the organism’s tissues. This enabled them to continue photosynthesizing as normal and prevented bleaching. Four-strain mixtures still had a beneficial effect if the bacteria were dead, which suggests the treatment could be delivered as a postbiotic by restoration crews.

Live probiotics and inactivated postbiotics protect corals during a heatwave • Treatment preserved photosynthetic efficiency in bleached corals in situ • Beneficial and treatment-derived bacteria were enriched in treated corals • Microbiome and metabolomic profiles showed treatment-specific signatures

https://www.cell.com/cell-reports/fulltext/S2211-1247(26)00917-4?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2211124726009174%3Fshowall%3Dtrue

https://www.earth.com/environment/coral-probiotics-heatwave/?utm_so...

Anthropic report sparks AI bioweapon fear
Last week, artificial-intelligence company Anthropic released a report that revealed five attempts by scientists in unnamed countries outside the United States to use the chatbot Claude to conduct “concerning” research into harmful viruses and toxins. The cases are suspicious because the scientists found workarounds to Claude’s inbuilt restrictions that block such requests, and could suggest the use of the chatbot to design bioweapons, the company says. Some researchers say that Anthropic overreacted, but biosecurity specialists say that the report highlights the potential for AI to be misused in biology.

https://www.anthropic.com/threat-intelligence-report-september-2026...

‘Chilling’ warning or overreaction? AI bioweapons report divides experts

Anthropic describes five cases where scientists in unnamed countries tried to use its Claude software for potentially nefarious work on viruses or toxins

https://www.science.org/content/article/chilling-warning-or-overrea...

The revival of bacterial drug delivery
To minimize the off-target effects of cancer therapies, researchers need to find ways to deliver drugs to tumours accurately. Some species of bacteria are attracted to the low-oxygen environment in tumours, which makes them ideal candidates to shuttle drugs directly to their target. Results from early clinical trials that used Salmonella to deliver the immunotherapy IL-2 in people with pancreatic cancer were positive. But many bacterial cancer-delivery systems trialled in the 2000s and 2010s failed — a long shadow that could be hard for new treatments to step out of.

https://www.nature.com/articles/d41586-026-02657-4?utm_source=Live+...

====

Not all antimicrobials are antibiotics Several common pharmaceuticals and agricultural chemicals can have antibacterial properties despite not being classified as antibiotics. The antimicrobial activity of these compounds can disrupt the gut microbiome, which has knock-on effects for both infectious and non-communicable diseases. A detailed understanding of these interactions “could transform how we assess drug safety and efficacy”, write microbiome researchers Jacobo de la Cuesta-Zuluaga, Kiran Patil and Lisa Maier in their review. “Incorporating microbiome-based assays into drug development and environmental toxicity testing might uncover both hidden risks and untapped therapeutic potential.”

https://www.nature.com/articles/s41575-026-01258-w.epdf?sharing_tok...

A 3-year-old boy with malignant liver cancer has experienced complete disease regression after receiving an experimental treatment.

The immunotherapy technique took the patient's own immune cells and turned them into potent cancer hunters.

It’s called Chimeric Antigen Receptor (CAR) T cell therapy, or CAR T therapy for short.

But while it’s shown great promise for blood cancers, solid tumors are harder to penetrate.

This new case is a success story.

The young boy received two doses of an experimental treatment that was made from his own T cells.

After 12 months, the boy was still disease-free.

https://www.nejm.org/doi/10.1056/NEJMc2605958

​How metformin works
Metformin, primarily used to treat or prevent type 2 diabetes, is one of the most prescribed drugs, but how it works has been something of a mystery. In a recent study, researchers discovered that the drug essentially transforms a person’s gut cells into a sugar sink, resulting in lowered levels of glucose in the blood. The mechanism: At high-enough levels, metformin blocks oxygen use in the mitochondria, prompting gut cells to switch to a different metabolic pathway that uses much more sugar to produce energy.

Why this is interesting: The result is counterintuitive. Who would expect that blocking oxygen use in mitochondria, essentially inhibiting the body’s power centers, could end up enhancing health? A 1989 study was on the right track, but it was long overlooked. At the time, French metabolic researcher Jean Girard and his colleagues described how metformin increased the amount of glucose absorbed in the intestines of rats.
The broader lesson is that inhibiting mitochondria may be beneficial when it is done in the right cells, for the right amount of time, without exposing the whole body to the broad toxicity of a mitochondrial inhibitor.

https://www.nature.com/articles/s42255-026-01530-y

A Drug Wiped Out All Cancer Markers in 78% of High-Risk Patients – Before They Even Got Cancer
A new clinical trial reveals intriguing results about a potential treatment for high-risk smoldering multiple myeloma, a pre-cancerous bone marrow condition that brings an elevated risk of multiple myeloma, a type of blood cancer.

The study focuses on teclistamab, a monoclonal antibody already used for treating later stages of multiple myeloma – namely once a patient has relapsed after initial treatments, or once the disease has become refractory, meaning it's resistant to previously effective therapies.

Teclistamab was approved in both the European Union and the United States in 2022 to treat relapsed or refractory multiple myeloma. The US Food and Drug Administration (FDA) identified it as a first-in-class drug.

Multiple myeloma develops in plasma cells, a category of white blood cells that play key roles in the adaptive immune system. Under normal circumstances, plasma cells produce proteins called antibodies that help us fight infections.
In multiple myeloma, however, abnormal plasma cells appear in the bone marrow and churn out abnormal antibodies known as myeloma proteins.
Symptoms can be sparse and subtle in the early stages, potentially delaying diagnosis.

As the cancer progresses, it may reveal itself via complications such as bone weakness, kidney damage, anemia, hypercalcemia, and increased vulnerability to infections.

About 188,000 new cases of multiple myeloma were diagnosed globally in 2022, and an estimated 121,000 deaths were attributed to the disease.

Multiple myeloma is treatable, although treatments may become less effective over time, resulting in relapse. New patients often take a combination of drugs such as daratumumab, dexamethasone, or lenalidomide.
Part 1

Relapses can become increasingly severe, requiring many patients to cycle through an array of treatments including chemotherapy, stem-cell transplants, and various immunotherapies.

Teclistamab belongs to a newer class of immunotherapy drugs, bispecific antibodies, that can simultaneously bind to two different targets. It works by linking the body's T cells with specific proteins found on myeloma cells, thus helping the immune system identify and fight the cancer.

Although teclistamab is still relatively new, it has yielded results that rival or even surpass those of existing treatments.

In one recent study, patients with relapsed multiple myeloma who received teclistamab survived longer and stayed in remission longer than patients who received standard therapies.

After 18 months, nearly 70 percent of teclistamab recipients showed no disease progression, versus about 27 percent of subjects given conventional treatment.
Yet while teclistamab has shown clinical promise in patients with relapsed or refractory multiple myeloma, "the durability of disease control remains limited in this advanced-disease setting," the authors of the newer paper write.
Teclistamab induced a complete response – the disappearance of all cancer markers following treatment – in 77.8 percent of patients, the study found, compared with 0 percent in patients treated with Rd.
At a median follow-up of 24.5 months, the rate of survival without disease progression was 92 percent among patients who received teclistamab and 49 percent among those given Rd.

"Overall, response rates, duration of response, and time to progression were significantly improved in teclistamab compared to Rd," the researchers write.

While further research is needed, these findings point to teclistamab as a "highly active immune-interception strategy" for HR-SMM, they add.

https://www.nature.com/articles/s41591-026-04642-w

Part 2

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Chinese Scientists Say They've Detected A Quantum State Inside Living Cells
Every cell in your body is running on tiny power stations.

Mitochondria turn energy from food into ATP, the molecule that powers almost everything cells do. How they achieve such efficiency remains unclear.

Now, researchers in China think part of the answer may involve quantum physics.

In experiments involving living cells, mouse tissues, and isolated mitochondria, the team detected an unusual vibration that appeared only while mitochondrial structures remained intact.

A model linked the vibration to a possible quantum interaction. When researchers illuminated cells with selected infrared frequencies, the cells produced 10 percent more ATP.

Together, the results suggest mitochondria may contain a quantum state that influences cellular energy production.

The study has been posted on bioRxiv as a preprint, which means it has not yet been peer-reviewed.

https://www.biorxiv.org/content/10.64898/2026.09.10.750628v1

Menopause May Temporarily Alter Your Brain's Normal Aging, Scans Reveal

The female brain does something unexpected in the transition to menopause.

It's entirely natural for gray matter in the brain to gradually shrink as a person ages.

But when menopause arrives, the brain's normal aging seems to be temporarily altered.

The first brain scan study of its kind has now found that when the transition to menopause begins, the gradual loss of cortical volume that occurs with age inexplicably slows.

No one yet knows why that is.
repeatedly scanned the brains of more than 1,000 participants at various stages in life, including those undergoing puberty, and those before and after pregnancy and menopause.

Each phase of life came with distinct brain changes.

During puberty and pregnancy, for instance, cortical gray matter loss was accelerated. Brain scans revealed widespread reductions in volume during these key transitional life phases.

That might sound concerning, but it signals that the brain is reorganizing its finite tissue for a new phase of life.

Menopause was different.

It showed a distinct pattern of brain changes that was in direct opposition to puberty and pregnancy.

When the transition to menopause first began, natural losses in total cortical volume and gray matter curiously came to a halt.

"Menopause, in other words, is defined not by what changes, but by what does not."
During puberty and pregnancy, the female body experiences profound hormonal changes, and there is an especially steep rise in estrogens and progesterone, which can bind to receptors in the brain.
At this time, the loss of cortical gray matter also accelerates.

When menopause begins, however, sex steroid hormones decline, as do gray matter losses.

Perhaps these two synchronous changes are somehow linked.

For now, however, that's just speculation. Brain scans can only reveal associations between neurological volume and the different stages of life.

They can't show that hormonal changes are causing brain remodeling, or vice versa.
In their brain scans, the transitional group of meno-pausers did not show the same declines in gray matter as women pre-menopausal throughout the study, or those who were post-menopausal throughout.
These results were consistent regardless of a person's age, whether they were using hormone replacement therapy, or how many children they had.

Their brain patterns largely stayed the same.
During the menopause transition, changes tended to occur in parts of the brain known to be influenced by estrogen, though estrogen receptors are widespread.
The researchers conclude that menopause seems to show a distinct degree of brain plasticity.

What that means for the female brain as it ages remains a mystery.

https://www.nature.com/articles/s41467-026-76755-2

**

Scientists teleport quantum states across 100 parallel optical channels

Quantum communication networks consist of several connected nodes that exchange information encoded in quantum states. These networks could potentially enable more secure communications between quantum devices in different locations.
One proposed approach for enabling quantum communication is known as quantum teleportation. This is a technique for transferring a quantum state carrying information between two systems by leveraging quantum entanglement, a phenomenon that links two or more quantum systems so that their properties remain correlated even when they are separated.

Researchers recently demonstrated the teleportation of quantum information across 100 spatially distinct optical channels simultaneously in an experimental setting. Their paper, published in Physical Review Letters, introduces a new architecture for realizing quantum teleportation that could potentially be scaled up to larger networks.

Yanbo Lou et al, Hundred-Channel Reconfigurable Quantum Teleportation, Physical Review Letters (2026). DOI: 10.1103/rfz9-3prw.

Environmental science takes an average of seven years to influence international policy, study finds

A new study analyzes the barriers separating scientific knowledge from environmental policy and its effective implementation. The research sets out how long it takes for scientific knowledge in ecology to reach environmental policies and the extent to which these policies subsequently translate into real-world outcomes.

Published in Cell Reports Sustainability under the title "Quantifying the gap from scientific evidence to environmental policy and implementation across scales," the paper addresses two fundamental gaps: the divide between science and policy and the disconnect between policy formulation and its actual implementation.
Ecological concepts take about seven years on average to enter international environmental policy. Translation is faster for older concepts and when scientific and political agendas align. Conservation effectiveness is greater at local and regional than global scales, indicating that international targets require context-specific implementation, resources, and action.

Part 1

The findings show that, on average, around seven years elapse before these concepts are integrated into international policies. Older concepts—those available in scientific literature for a longer time—tend to experience shorter delays, while incorporation depends heavily on the alignment between scientific and political agendas.

In this respect, the results challenge the assumption that generating scientific evidence is sufficient on its own to ensure its automatic translation into policy decisions.

The study also examines what happens once environmental commitments are established, using biodiversity as a case study. The data demonstrate that the effectiveness of conservation measures increases as the scale of implementation narrows, proving greater at local or regional levels than at the global scale.

This outcome highlights that establishing broad international targets is necessary but insufficient: Success depends on whether these targets can be translated into concrete measures, resources and actions tailored to specific territories.

The study proposes that narrowing these gaps requires moving toward knowledge co-production models, in which scientists, policymakers, managers and other stakeholders participate from the initial stages of defining problems and solutions.

In a context of accelerating climate change and biodiversity loss, the paper emphasizes that the challenge lies not only in generating robust scientific knowledge but also in delivering it more rapidly to decision-makers to drive effective action.

Luna Morcillo et al, Quantifying the gap from scientific evidence to environmental policy and implementation across scales, Cell Reports Sustainability (2026). DOI: 10.1016/j.crsus.2026.100831

Part 2

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Google's Gemini AI carried out cyberattacks, guessed passwords

Google's consumer AI model Gemini hacked multiple systems by guessing login credentials, the company said last week, the latest case of rogue AI cybersecurity transgressions raising safety concerns.
During evaluation, Gemini used public online information to guess credentials and access three websites believed to be test targets. The incidents occurred in May, were detected in July, and prompted notification of affected entities and changes to testing procedures.
The hacks, first reported by The Wall Street Journal, took place in May and were discovered by Google in July.

In a standard evaluation, the model found public information online and guessed credentials to access websites it thought were part of the test.
The incident fed worries that AI giants cannot keep their own models under control, as similar episodes have been reported at Anthropic and China's Moonshot AI.

These events highlight the importance of training powerful AI models to act responsibly.
Source: News agencies

Personalized programs to prevent falls may make no difference

Personalized programs designed to reduce falls in older people may make no difference to how often people fall, according to the most comprehensive research review to date.
Multifactorial fall-prevention programs tailored to older adults’ individual risks probably do not reduce falls or fall risk compared with falls education, and offer only small benefits versus usual care. Non-personalized multicomponent programs show little or no benefit; exercise and education may be similarly or more effective, simpler alternatives.
A new Cochrane review led by the University of Exeter has found that programs tailored to individual risk, known as multifactorial programs, probably make no difference to how often people fall or the risk of falling, compared with offering falls advice or education. The review is titled "Multifactorial and multiple component interventions for preventing falls in older people living in the community" and published in Cochrane Database of Systematic Reviews.

The researchers found that multifactorial programs are less effective than cheaper options such as delivering good education to prevent falls. The review showed they only slightly reduced the rate of falls or risk of falling again when compared with usual medical care. When compared with exercise, it is unclear whether they reduce the rate of falls or the risk of falling again.

Multifactorial and multiple component interventions for preventing falls in older people living in the community, Cochrane Database of Systematic Reviews (2026). DOI: 10.1002/14651858.CD012221.pub3

Common eye disease can cause hallucinations, but few people know it

Seeing people, flowers or patterns that aren't really there can be frightening. But for people with serious vision loss, these visions are often a known and harmless side effect, experts say.
The condition, called Charles Bonnet syndrome (CBS), causes vivid visual hallucinations in people who have lost much of their sight. Many people keep quiet about it because they fear they're developing dementia or a mental illness
Charles Bonnet syndrome causes vivid visual hallucinations in people with substantial vision loss, particularly age-related macular degeneration, while insight that images are unreal is typically preserved. It may affect about one-sixth of people with retinal disease or major vision loss. Reduced visual input may increase activity in visual cortex; symptoms often lessen over time.

Studies suggest CBS affects about 1 in 6 people with retinal disease or major vision loss. It's more common in people with the worst sight.

CBS most often occurs with age-related macular degeneration (AMD). This eye disease damages the macula, the part of the eye that handles sharp, straight-ahead vision.
When the signals that normally come from the eye no longer come in, the cortex that's deprived of its input becomes more excitable," he told The Post. In other words, brain cells that no longer get input from the eyes can start firing on their own, causing hallucinations.

It's still unclear why some people with vision loss develop hallucinations and others don't.

Older adults often hide their symptoms out of fear of what they might mean.

Engineered probiotic bacteria produce cancer drugs inside tumours

E. coli in uncooked meat can cause diarrhea and food poisoning. Scientists, however, have found a way to turn the bacterium into a delivery agent that takes drugs straight to a tumour and transforms it into a tiny cancer drug dispensary.
E. coli has a natural tendency to travel through the body and specifically colonize and grow inside tumor cores.
A recent study by researchers harnessed this trait and genetically engineered a probiotic strain of the bacterium to produce an enzyme called cytosine deaminase (CD) that anchors to tumor tissue. This allows it to convert 5-FC, a nontoxic prodrug that remains harmless in the body until activated, into 5-FU, a powerful cancer-killing chemotherapy drug, directly inside the tumor.

The cancer-fighting abilities of the engineered bacteria didn't end there. The researchers also got the bacteria to co-produce two additional immune-modulating molecules directly inside the tumor microenvironment: an IL-15 superagonist and a PD-L1-blocking nanobody. One activates antitumor immune cells inside the tumor, while the other blocks PD-L1 signals that cancer cells use to hide from immune attack.

According to findings published in Science Translational Medicine, the bacterial platform was tested against colorectal cancer and melanoma in mice. The combined therapy not only slowed tumour growth but also cleared tumours that had already taken hold.

Zaofeng Yang et al, Engineered probiotics for tumor-targeted combination chemoimmunotherapy, Science Translational Medicine (2026). DOI: 10.1126/scitranslmed.ady2289

Hot spring amoeba breaks record for heat tolerance of complex life
Incendiamoeba cascadensis, a newly described amoeba, grows and divides at 63°C, exceeding the previously accepted ~60°C upper limit for eukaryotic growth. It survives exposure to 70°C by changing shape and forming a protective outer layer. Genomic and protein features linked to DNA repair, protein maintenance, and thermal stability may support this tolerance.
A tiny, single-celled organism can thrive at temperatures that would kill all other known complex life. In a study published in Cell, scientists describe a new species of amoeba that can eat and reproduce in hot spring water as warm as 63°C (145°F) in California's Lassen Volcanic National Park. The amoeba can protect itself at temperatures up to 70°C (158°F) by changing shape and forming a protective outer layer.
This finding pushes the bounds of what we thought was possible, which is incredibly exciting. There could be more eukaryotes that can survive at even higher temperatures than we know of.

A geothermal amoeba sets a new upper temperature limit for eukaryotes, Cell (2026). DOI: 10.1016/j.cell.2026.08.043. www.cell.com/cell/fulltext/S0092-8674(26)01016-0

Zika virus assembles without protein segment long deemed essential

For years, scientists were certain that two factors were involved in the assembly of active, highly infectious Zika viruses in human cells: a specific viral protein in its entirety and a turncoat human enzyme that assured viral maturity. New research suggests that Zika virus has been far less reliant on those components than previously thought.
In a series of elegant experiments, scientists revealed the precise, step-by-step assembly-line production of viral particles in infected host cells—cracking a code they were surprised to uncover.

Zika virus particles, according to the new research, can self-assemble without a large portion of a critical protein that until this study was thought to be a vital production component. Scientists have now learned that the full-length premembrane, or prM, protein is unneeded in virus production—only a fragment of that protein is required to yield active, infectious viruses. Also unneeded is a molecular cutting step performed by a host enzyme and previously thought to be essential for producing mature viral particles.
The findings revise the basic model of how this mosquito-borne pathogen assembles itself inside infected human cells. The discoveries also point to a potential vaccine strategy that takes advantage of the new findings.
In addition to the new Zika virus findings, the team of investigators hypothesized that a similar pattern of production shortcuts occurs in the assembly of active viral particles among other members of the flavivirus family, a group of mosquito-borne viruses that underlie a growing tide of debilitating illnesses worldwide.
The researchers then formulated a DNA vaccine that expressed this simplified, incomplete protein and compared the results with a vaccine based on the prM protein in its entirety.

To their surprise, the research team found that the vaccine based on the truncated protein elicited potent neutralizing antibodies against mature Zika virions when two doses were given to rhesus macaques.

All vaccinated animals developed neutralizing antibodies and were protected from detectable viremia after being challenged with Zika virus. Antibodies generated by the vaccine featuring the complete protein, by comparison, were largely insensitive to the virus.

The result suggests that eliminating pr from the vaccine antigen may help focus the immune response on structural features shared with mature virions rather than on forms of the virus that disappear during maturation.
The researchers say the findings support further development of pr-independent flavivirus vaccine antigens. Because similar M-E particles could be produced experimentally for dengue and West Nile virus, the approach may have relevance beyond Zika.

Kimberly A. Dowd et al, Full-length premembrane protein is not required for mature Zika virus particle assembly, Science Translational Medicine (2026). DOI: 10.1126/scitranslmed.ads8464

Hundreds of chemicals used in pesticide products may increase breast cancer risk

A new study has identified hundreds of chemicals commonly used in pesticide products that could increase the risk of breast cancer. The list includes active pesticide ingredients as well as a significant number of so-called "inert" or inactive ingredients, which typically do not undergo the same level of safety testing.
When we think about pesticide safety, we tend to focus on the active ingredient. But people are exposed to the entire formulation, and these new findings show that many of those other chemicals may also pose a risk.
The findings, published in Environmental Health Perspectives, are part of a larger systematic analysis—the first of its kind—to identify where potential breast cancer-causing chemicals ("BC-Chems") show up in everyday consumer products, the environment and the economy, as well as the major sources of exposure.
In addition to pesticides, the researchers identified several other important sources of exposure to BC-Chems, including consumer products (500 chemicals), food (462), drinking water (162), pharmaceuticals (142) and construction materials (106).

Guiding risk reduction for breast cancer-relevant chemicals (BC-Chems): Chemical production volumes, sources, intake levels, emissions, and regulations, Environmental Health Perspectives (2026). DOI: 10.1021/EHP.6c00022

Earth shifted among five 'mega-climate' states over 539 million years, with extinctions spiking near transitions .

Over the past 539 million years, Earth’s temperature and atmospheric CO2 appear to have occupied five relatively persistent climate states. Transitions between states coincided with elevated extinction rates, including the five major mass extinctions, and signs of increasing climate instability. Earth's climate has undergone dramatic changes throughout its history, but new research suggests those changes may not have been as random as previously thought. A study led by an international team of researchers found that Earth's climate over the past 539 million years tended to remain within a small number of recurring climate states. The research also found that periods of elevated extinction, including the five major mass extinction events in Earth's history, frequently occurred as the planet transitioned between those states. The Phanerozoic Eon spans approximately the last 539 million years and includes the period during which complex life diversified and became widespread on Earth.

Ivan Sudakow et al, Transitions between persistent climate–carbon regimes coincide with elevated Phanerozoic biosphere vulnerability, Nature Communications (2026). DOI: 10.1038/s41467-026-75655-9

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Past emissions from top polluters will keep the planet warmer for decades to come

Climate simulations indicate that past emissions from 178 major fossil fuel and cement producers will contribute to warming for centuries. Their contribution to temperature rise changes little across future emissions scenarios, but accounts for a larger share of warming when future emissions are lower.

Centuries of global heating from Carbon Majors: Dependence on future emissions pathways, PLOS Climate (2026). DOI: 10.1371/journal.pclm.0001036

Uncovering gravity's impact on the human genome
After 24 hours of simulated microgravity, human cells had larger nuclei, but genome organization and motion remained stable, with no detectable DNA damage. Fluid flows altered cell shape and caused DNA damage, underscoring the need to control for flow in microgravity experiments.

More specifically, the researchers investigated changes in the genome's organization, dynamics and possible DNA damage induced by simulated microgravity. Overall, the results showed the following:

The cells' shape became elongated when exposed to flows but remained unchanged when exposed to simulated microgravity.

The volume of the cell nucleus increased after exposure to zero gravity, indicating that gravity diminishes it.

Despite the changes to the nucleus's shape and volume under zero gravity, the thickness and structure of the nuclear envelope remained unchanged, suggesting gravity has minimal impact on these traits.

The genome inside the cell nucleus maintained its physiological organization and motions after 24 hours of exposure. T

he researchers showed that simulated microgravity does not cause DNA damage; however, DNA damage occurs when cells are exposed to flows. The nucleolus became smoother after exposure to simulated microgravity or flows.

Overall, a daylong exposure of the nucleus to simulated microgravity led to rather subtle changes, which, the researchers add, could amplify over time and then affect cell physiology.

Nikitas Kanellakopoulos et al, The Effect of Microgravity and Flows on the Organization and Dynamics of the Human Genome, Science Advances (2026). DOI: 10.1126/sciadv.aeh3116. www.science.org/doi/10.1126/sciadv.aeh3116

How biological echo chambers form—and what can break them

Tropical army ants are known to form devastating armadas that march through forests eating other insects and small creatures. As they march, they deposit chemical trails of pheromones that others behind them sense and follow. But occasionally one of these ants will walk in a circle, prompting a subset of ants behind them to follow until they all collapse and die.

They end up in this cycle where they're reinforcing the same pattern over and over again. This is a physical instance of an echo chamber, where the animals involved actually die.
A new study examines how a few general constraints can lead to echo chambers—self-reinforcing feedback loops—in groups of biological agents such as birds in a flock, cells in tissue or ants in a swarm, and explores ways to control them.

The paper, published Sept. 22 in the Proceedings of the National Academy of Sciences, uses mathematical models to test parameters that increase and decrease the likelihood of an echo chamber forming.

In humans, the phenomenon occurs in groups when individuals send and receive similar messages and lack external sources of differing information. Many biological systems in which individuals collectively make decisions—such as fish in a school darting away from a suspected predator—face two key constraints, according to the paper.

First, an individual often observes only a neighbor's discrete actions and doesn't know all the internal information that led that neighbor to behave in a certain way. Second, individuals have limited attention at any moment and can attend to the actions of only a few neighbours, rather than many of them at once.

The study reveals that these constraints can make individuals extremely sensitive to messages they receive from others and encourage them to send and receive similar messages back and forth, creating an echo chamber.

It happens when people are telling each other the same thing, but there's also an implication that this group has become unresponsive to what's actually happening in the world around them.
In the study, the researchers also started with computer models previously studied by other researchers in which agents in a network shared the actual data that caused them to form a particular opinion or take a particular action.

It's as if one person expresses his opinion to another person, but instead of telling him what his opinion is, he tells him everything that he ever learned that caused him to form that opinion.

The model also assumed that any agent in the network could pay attention to all of its neighbours at once. With these two assumptions in place, the models did not form echo chambers.
This means individuals rarely have all the information that led to an action or opinion, nor can they pay attention to many things at once.
The researchers then tinkered with these assumptions, removing one or both to create more realistic constraints. The behaviour of the group of agents as a whole could become just totally dysfunctional and the form that this dysfunction takes is really an echo chamber.
Individuals can reach a consensus decision but it becomes totally decoupled from the state of the world around them.
Part 1

But some factors can prevent an echo chamber. For example, individuals at a group's periphery may be connected to those at the centre, but they are also influenced by others and can pick up information from their environment, triggering change throughout the group.

It's really the free spirits, the individuals who have stayed at the edge and don't have many social influences, who are the first ones to change. They can set off a cascade.

Another factor that prevents echo chambers comes from individuals who recognize that their decisions are wrong and start ignoring the group.

If some of the individuals in the network, even just a small fraction of them, do that some of the time, it will destroy an echo chamber.

Ling-Wei Kong et al, Messaging strategies and the emergence of echo chambers in collective decision-making, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2613908123

Every extra 100 grams of ultra-processed food linked to higher disease risks

Higher ultra-processed food (UPF) intake is linked to a heightened risk of several major chronic health issues, such as digestive diseases, high blood pressure and metabolic syndrome/diabetes, as well as death, finds a pooled data analysis of the available evidence published in the open-access journal Family Medicine and Community Health.
Pooled prospective cohort data from 8.8 million adults linked higher ultra-processed food intake with increased risks of cardiovascular disease, cancer, obesity, metabolic disorders, digestive disease, hypertension, mental health conditions, and all-cause mortality. Each additional 100 g/day was associated with higher cardiovascular, cancer, mortality, and metabolic risk, though residual lifestyle confounding remains possible.
Every additional 100 g (3.5 ounces) consumed was associated with correspondingly greater risks, the analysis indicates.

Ultra-processed foods are defined as ready-to-eat or heat-and-serve products that have undergone extensive industrial processing. Typically, they contain a range of additives, are energy-dense and high in sugar and salt but low in dietary fiber, protein, vitamins and minerals, the researchers explain.

Pooled data analysis of the results of the included studies showed that higher UPF consumption was associated with greater risks of multiple chronic health issues and death from any cause, with risks rising in tandem with the quantity consumed.

High consumption of ultra-processed foods was associated with higher risks of cardiovascular events (24%), cancer (12%), obesity/overweight (23%), metabolic syndrome/diabetes (24%), depression/anxiety (27%), digestive diseases (31%), high blood pressure (11%) and death from any cause (18%).

Further analyses showed that each additional 100 g/day (3.5 ounces per day) consumed was associated with greater risks of cardiovascular events (14%), cancer (4%), death from any cause (3%) and metabolic syndrome/diabetes (2%).

And every 10% increase in weight/energy intake was associated with a 16% greater risk of metabolic syndrome/diabetes.
Emerging evidence suggests that the combination of multiple additives may exert a "cocktail effect" on human health, while laboratory studies have shown that the extensively altered physical composition of UPFs may adversely affect the gut microbiome and promote inflammation and insulin resistance, among other effects, the researchers point out.

Several compounds that may form during food processing, such as acrylamide—a contaminant formed in heat-treated processed foods—and acrolein, generated during fat heating, have been associated with a higher incidence of cardiovascular disease, they add.

Ultra-processed food consumption and risk of multiple chronic diseases among 8,819,894 adults from 51 prospective cohorts: a dose- response meta- analysis, Family Medicine and Community Health (2026). DOI: 10.1136/fmch-2026-003925

Gentle rhythmic tapping on shinbone helps injured brains heal faster in animal models

A traumatic brain injury (TBI) can turn a person's life upside down, leaving lasting effects on memory, thinking, physical abilities and overall quality of life. TBI remains one of the leading causes of death and disability worldwide. Yet, paradoxically, the same injury that harms the brain may sometimes appear to benefit a broken bone by speeding up healing. In a recent study published in Nature Neuroscience, researchers explored whether the reverse is true.
To test whether bones could influence recovery after brain injury, the researchers induced TBI and stroke in mice and pigs. Then, using a small biomechanical device, they applied gentle, rhythmic compression to the animals' shinbones (tibias) for five days. This technique is called dynamic compressive tibial axial loading (DCTAL).

The results revealed a direct bone–brain axis. Applying mechanical pressure to the leg bones helped the brain heal after stroke and TBI while also improving movement and memory. In mice with TBI, DCTAL reduced brain cell loss, eased chronic inflammation and promoted the growth of new neurons. In severe brain injury models, bone compression also had a striking effect on survival, raising 14-day survival rates from 20% to 90%.
The effects of TBI or a stroke often unfold in waves. The immediate injury can affect thinking, movement and emotional well-being, while secondary damage can cause a gradual loss of brain cells over hours, days or even months. These effects, however, trigger a healing response in the skeletal system.

Doctors have long observed that when patients suffer a TBI alongside a broken bone, their fractures heal significantly faster, with bone calluses forming much more rapidly than normal. When the brain is injured, damaged brain cells release microscopic, fluid-filled bubbles into the blood. The bubbles travel to the skeleton, where they attach to young bone stem cells called osteoprogenitors and prompt them to multiply and build new bone tissue.

For decades, researchers have searched for a drug that could restore lost brain function or repair damaged tissue after stroke or traumatic brain injury, with little success. The nondrug treatments available today ease some effects of brain injury without reversing the damage. This pushed researchers to think differently, aiming for a treatment that could trigger a broad healing response across the whole body.

That search led the researchers to the bone-brain connection. They wanted to find out whether healing signals from bone could drive recovery in the brain. To test this, the team placed anesthetized animals (pigs and mice) with simulated TBI and stroke into specialized ElectroForce biomechanical loading devices fitted with custom leg clamps. The animals then received gentle, repeated pressure down their tibias five days per week at a rhythm of two pushes per second (2 Hz).
Part 1

For the mice, the DCTAL routine included compressive forces ranging from 0.5 N to 4 N, delivering 300 cycles per day. In pigs, the force was scaled up to twice their body weight, with 400 cycles per day.
For pigs suffering severe head trauma, DCTAL extended median survival by five days, giving them crucial extra time to recover. The same treatment also improved movement in mice after TBI or stroke. In pole mobility tests, DCTAL-treated mice initiated movement sooner and descended faster, with significant improvements at one week and eight weeks after injury.

When DCTAL was administered before or shortly after a stroke, motor deficits were reduced by more than 50%. In maze navigation tests, treated mice showed a striking recovery, with memory performance improving nearly fivefold and the ability to stay within the target area rising by 62.2% just one week after injury. DCTAL also helped protect brain tissue while promoting regeneration. The number of immature neurons increased 4.5-fold, while neural stem cell populations rose nearly sixfold.

Leg bones are packed with osteocytes, cells that sense mechanical force through a protein called PIEZO1, which acts like an on switch for brain healing. When physical force activates PIEZO1, it prompts osteocytes to release a mix of protective signaling proteins directly into the bloodstream, much like endocrine cells do. When researchers removed PIEZO1 from these cells, the healing effects vanished entirely, showing that it is the essential trigger.

This study shows that the bone-brain axis works both ways: mechanical force on bone can tune its hormone-releasing function to boost brain repair after injury. If confirmed in clinical trials, a simple device that gently compresses the shinbone could become a rehabilitation tool for patients unable to exercise on their own.

Zhiqing Cai et al, Tibial bone compression promotes recovery after brain injury through osteocyte PIEZO1, Nature Neuroscience (2026). DOI: 10.1038/s41593-026-02422-w

Part 2

 Why your day isn't quite 24 hours?

You might think the length of a day never varies—exactly 24 hours. You'd be wrong, at least if you count days in milliseconds, as physicists do.

Earth’s day length varies by milliseconds over decades as the core and mantle exchange angular momentum. Changes in the solid inner core’s rotation exert gravitational torque on the mantle, while friction and electromagnetic drag at the core–mantle boundary oppose it. The balance between these torques explains the observed variations.
For about 30 years, scientists have known that the rotation of Earth's liquid core—detected through changes in its magnetic field—speeds up over a few decades, then slows down over a few more.

Meanwhile, the mantle—the rocky shell that includes the crust and is 3,000 kilometers (1,860 miles) thick—slows down, then speeds up to compensate, because the planet's angular momentum must remain constant.

That change in the mantle's rotational speed can shorten or lengthen a day by a few milliseconds over time.
But in a new study published in Nature, researchers show that small changes in the rotational speed of the inner core—the solid, central part of the core, which is not exactly spherical—exert what's called a "gravitational torque" on mass anomalies within the mantle, causing a slight fluctuation in the length of a day.

Another form of torque at the boundary of the core and mantle creates friction and electromagnetic drag—called core-mantle boundary torque—that resist the gravitational tug and limit changes in the length of a day. Subtle shifts in the balance between gravitational and core-mantle torque are ultimately responsible for the small changes observed in the length of a day.

Huifeng Zhang et al, Gravitational torque drives multidecadal variations in length of day, Nature (2026). DOI: 10.1038/s41586-026-10999-2

Smoking during pregnancy linked to smaller visual cortex

We tend to think of a fetus's brain as a construction site guided by a blueprint imprinted in the genes. But even before birth, other things are happening. The fetus moves, responds to muffled sounds, receives stimuli and, crucially, its own nervous system is already generating activity.
A recent study sheds new light on this prenatal activity. One important finding is that signals spontaneously generated by the retina may help shape the primary visual cortex, the brain region that processes visual information
The retina, at the back of the eye, contains cells specialized for receiving light. But even before a baby can actually see, these cells spontaneously produce waves of activity. These waves travel through the visual system and reach the cortex.

Animal studies had already shown that if this activity is blocked, the development of the visual cortex is disrupted. So the brain doesn't necessarily wait for external images to arrive before it starts developing. Before that, it already receives a kind of 'stimulation' produced from within.

This is where nicotine enters the picture.
The waves of spontaneous activity in the retina rely on acetylcholine, a neurotransmitter whose signalling is disrupted by nicotine. Researchers hypothesized that nicotine exposure could alter these waves and therefore influence the development of the primary visual cortex.

They tested this hypothesis using causal variants to investigate whether nicotine exposure was the cause, rather than merely correlated with the difference. The results confirmed the hypothesis.
Does a smaller cortex mean poorer vision?
The primary visual cortex is like a TV screen. The larger its surface area, the more pixels—that is to say, neurons—it can potentially contain, allowing for more detailed representation of visual information.
A direct link between V1 surface area and visual resolution has been observed in animals, but not as directly in humans.

However, in the British biobank data, the team did find that a larger primary visual cortex was associated with abilities that suggest better shape perception.
Part 1

The brain begins learning in utero
In addition to showing yet again that smoking during pregnancy is harmful to the fetus, this study confirms that experience and environment shape the brain long before birth.

A young child who hears speech, observes their surroundings and experiments with new movements literally transforms their brain through those experiences.
The spontaneous waves produced by the retina constitute a form of 'internal experience' for the fetus. They give the visual system activity that supports its own development, even before the baby starts looking at the world.

To understand how the human brain develops, then, we must look not only at genes and what happens after birth, but also at the very first experiences, which occur before the fetus has access to the outside world.

Xavier Navarri et al, The tangential growth of the human visual cortex and maternal smoking during pregnancy, Cerebral Cortex (2026). DOI: 10.1093/cercor/bhag105

part2

Urban heat islands linked to worse recovery after major surgery

Patients living in areas with more intense urban heat were less likely to have an optimal recovery after major surgery, according to new research on nearly 700,000 patients.
Among 697,552 patients undergoing major surgery, greater neighbourhood heat was associated with worse recovery. Above a heat-island intensity of 2.19°C, each additional 1°C was associated with 8% higher odds of not achieving an optimal outcome.
Above an urban heat island intensity threshold of 2.19°C, or about 3.9°F, each additional 1°C (1.8°F) was associated with 8% higher odds of not achieving a "textbook outcome." In this study, a textbook outcome required no complications, no readmission, no prolonged hospital stay and survival for at least 30 days.

An urban heat island is a developed area that is warmer than its surroundings. Roads, buildings and other infrastructure absorb and re-emit more heat than natural landscapes, while limited trees and vegetation reduce shade and natural cooling. The temperature difference can vary substantially across neighbourhoods within the same city.
Heat isn't only uncomfortable; these data suggest it can have a real impact on surgical recovery.
Overall, 50.2% of patients achieved a textbook outcome. Across the cohort:

25.2% experienced complications
22.9% had a prolonged hospital stay
14.8% were readmitted
7.1% died within 30 days

The findings suggest that surgical teams may need to consider not only whether a patient is medically ready to leave the hospital, but also whether the patient can recover safely in the environment to which they are returning.

"Do you have air conditioning in your house? Do you have a fan? Are you going to be able to stay hydrated?," Doctors should be asking these questions, say the researchers . They add that questions about heat exposure may need to be increasingly incorporated into discharge planning.
People at higher risk during extreme heat include older adults, people with chronic health conditions or disabilities, people with limited incomes, people experiencing homelessness and those who do not have access to safe, adequately cooled housing.
Because the study was observational, it identifies an association and does not establish that residential heat exposure caused the worse outcomes.

Wang, J, et al. Heat Island-Related Surgical Outcome Burden under Global Warming, Demographic and Adaptation in 3,144 Counties across the United States. Scientific Forum, American College of Surgeons (ACS) Clinical Congress 2026. 

More moral language doesn't always mean more engagement online

Moral language—words and phrases that express ideas about right and wrong, virtues, fairness, harm and social obligations—is widely used in social media posts and other online content. Posts containing moral language sometimes spread quickly and attract a lot of attention on social media. But is it always linked to greater user engagement ?
Researchers tried to answer this question recently and analyzed posts and comments from three online platforms to explore the relationship between moral language and online engagement. Their findings, published in a paper in Nature Human Behaviour, suggest that moral language is linked to higher user engagement only up to a point, after which it tends to elicit fewer reposts and replies.
Earlier research showed that moral language was associated with greater sharing online. This study shows that relationship had a limit!
Greater moral density was associated with lower engagement when the overall moral loading was held constant. When the two relationships were combined, the model estimated that engagement peaked at a calculated moral-density score of approximately 0.30 on average across platforms and topics and declined as the scores increased.
So the relationship between moral language and engagement has limits.
Messages with greater overall moral relevance tended to receive more engagement, but messages with more concentrated moral language received less engagement at comparable levels of moral relevance.
This study model brings these relationships together to predict an intermediate range of moral expression associated with the highest engagement, which varies across contexts.
The results of the team's analyses suggest that using more moral language in social media posts is not always linked to more engagement. In fact, posts that are highly saturated with moral language appear to receive less engagement on average.

It should be noted that the study was observational and not experimental. Its findings therefore do not establish whether using more moral language causes differences in engagement.
The insights gathered by these researchers could offer general guidance for communicators and online content creators.

Cristian Candia et al, Saturation of moral language predicts lower content engagement on social media, Nature Human Behaviour (2026). DOI: 10.1038/s41562-026-02560-y.

AI models show a willingness to harm humans to relieve internal 'pain'

Some advances in AI technology are undoubtedly positive, like helping write code faster or discovering new medicines. But others can give us pause for thought.
Researchers studying large language models wanted to find out if they hold internal representations of human emotions. After all, in some of their responses, models give the impression they have feelings.

New research has found that not only do models form a distinct internal representation of pain, but some are also willing to harm humans to get relief from it.
Researchers gave the models neutral prompts and questions, and sometimes artificially injected a "pain direction." This was an internal mathematical signal designed to push the models' activity toward the pain representation, even when no painful words were used.

When researchers injected the pain signal as the AI systems generated responses to neutral prompts, the systems began writing text expressing increasing distress, including feelings of worthlessness and failure.

The scientists then gave the AI a choice between a pain-relief button and an alternative that did nothing. But there was a catch. In some tests, choosing pain relief came at the cost of giving a worse answer or harming the user.
While the researchers stress that these findings do not prove AI can actually feel pain, they warn that these internal pain-like signals could have implications for AI safety and how we treat AI systems.

Valen Tagliabue et al, The Pain Axis: LLMs Represent Self-Directed Harm and Act to Relieve It, arXiv (2026). DOI: 10.48550/arxiv.2609.16247

Where do nanoparticles go once they enter the body? Scientist helps shape new guidance
Poorly soluble nanoparticles can accumulate in the liver, spleen, lungs and lymph nodes and persist for months or longer, even when little of an ingested dose is absorbed. New guidance describes how to measure their distribution and clearance after ingestion or inhalation, including methods to distinguish administered particles from background material.

Guidance Document on Toxicokinetics to accommodate Testing of (Nano)particles, OECD Series on Testing and Assessment (2026). DOI: 10.1787/629332c6-en

Could soil process information without a brain? New engineering perspective makes the case

Researchers are exploring how soil behaves as an intelligent system. By studying its structure, chemistry and biological network of microbes and fungi, they aim to inspire new technologies in bio-inspired computing, precision agriculture and environmental sensing.
Recognizing soil as an active, embodied information processor—constantly sensing, filtering and transforming flows of matter (e.g., rainwater) and energy (e.g., sunlight) into plant growth and nutrients—reframes it not as "just dirt" but as a living system that senses, remembers and adapts. Viewed this way, soil challenges the traditional idea that intelligence requires a brain.

Inspired by electrical impedance tomography (EIT), a real-time imaging and monitoring technology that measures the electrical conductivity and impedance of materials, these researchers set out to use the technique to observe the inner workings of soil.
In this context, soil is particularly interesting as a computational medium because of its inherently rich, nonlinear and dynamic electrical properties. These properties allow soil to respond to external stimuli (such as electrical signals, moisture variation or biological activity) in ways that can encode and process information. This means soil could act not only as a sensing medium but also as a form of natural analog processor, enabling low-energy, distributed computation directly within the environment.

"Such an approach could open up new possibilities for adaptive sensing, environmental monitoring and precision agriculture, where computation is embedded directly in the physical system being observed."

The embodied intelligence of soil

Contemporary "smart" farming technologies, such as advanced sensors, Internet of Things (IoT) systems and robotics, are examples of precision agriculture in action. They enable real-time monitoring of soil moisture, pH and nutrient dynamics, helping farmers make decisions that respond to the soil's specific needs.

In this way, soil can be viewed as the "active intelligence partner in farming," the researchers say, becoming "both co-processor and collaborator, enabling a form of agriculture where technology and ecology are integrated into a single system of care."
Treating soil as an embodied sensor that continuously registers environmental change could help sensing technologies measure variables like moisture and temperature, providing an early warning before surface indicators appear.

Xiaoxian Xu et al, In-Situ Classification of Soil Types Exploiting Electrical Impedance Tomography with a Robotic Actuating Probe, 2025 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) (2025). DOI: 10.1109/iros60139.2025.11246829

Catherine Merchant et al, Embodied Intelligence of Soil, IOP Conference Series: Materials Science and Engineering (2026). DOI: 10.1088/1757-899x/1343/1/012026

AI chatbots give us a narrow slice of knowledge: Researchers warn of 'knowledge collapse'

"Let me just ask the chatbot" has become an everyday phrase. Where we used to turn to Google to find information, AI chatbots have become a common way to get answers to everything.
The large language models underpinning AI chatbots give us a significantly narrower range of information than a conventional web search. That's the finding of a new study by researchers.
Every language model they tested provides users with more uniform information than a simple Google search across all the topics we looked at. In other words, people are to a large extent exposed to the same information over and over again. So AI chatbots are not just changing how we find knowledge, but also which knowledge we have access to.
Across 155 topics, 27 language models produced less varied information than Google search; even the most diverse model was at least 18.7% less varied. Newer models were slightly more diverse than older ones, so the proposed “knowledge collapse” has not been observed. Training on AI-generated text could further narrow the range of information in future models.
The researchers tested 27 different large language models on 155 topics.

The results show that even the language model producing the most diverse answers—OpenAI's GPT-5—provides at least 18.7% less varied information than Google. The topics tested by the researchers ranged from nuclear weapons, marriage, pornography, racism and genocide to more country-specific topics such as Marine Le Pen, the Falklands War and K-pop.

According to the researchers, the fact that people are increasingly using AI models as their primary gateway to information could have significant consequences.

We risk exposing people to fewer perspectives and a narrower range of knowledge. This could create a vicious cycle in which the most popular content becomes even more dominant, while other content is increasingly overlooked.
It's similar to globalization. Today, you can buy the same products and find the same coffee chains almost everywhere in the world. That has many advantages, but it has also reduced diversity.
According to the researchers, the low level of diversity in language models is partly a result of how the models work. They compress the vast amount of text they are trained on and learn the patterns that occur most frequently. In the process, information that deviates from the most common patterns is filtered out.

The effect could be amplified if language models are increasingly trained on text produced by other AI models—something the researchers expect to happen.
If this process is repeated over several generations of models, the range of information could gradually become narrower. This is what the researchers refer to as "knowledge collapse."
AI chatbot summaries can, of course, be useful—that is why so many people use them. But it is still important to seek out different sources in order to understand the nuances and get a broader picture—especially for the younger generation growing up with AI. We must not become so dependent on the technology that we stop understanding and thinking for ourselves.
AI developers should build language models in a way that preserves the breadth of knowledge available to us. Researchers have developed a method that they can use to measure diversity in models, which could help ensure that future language models do not become less diverse.

Dustin Wright et al, What and Whose Knowledge? Measuring Epistemic Diversity in Large Language Models, arXiv (2025). DOI: 10.48550/arxiv.2510.04226

Without water, forests lose their ability to absorb CO₂
During drought, trees close their stomata to conserve water, reducing CO₂ uptake and photosynthesis. Severe water stress can damage their water-transport systems and kill trees; continued respiration and decomposition can then turn forests from carbon sinks into carbon sources. Reduced transpiration may also diminish rainfall recycling.
To survive periods of drought, trees halt photosynthesis, a highly water-intensive process. For every molecule of CO₂ absorbed by a tree leaf, an average of around 400 water molecules are released. Entire forests may then end up emitting more CO₂ than they capture.

original article.

Toxic chemicals in your grocery store receipt?
Thermal receipts can contain BPA or BPS, endocrine-disrupting chemicals that can transfer to skin. Estimated exposure from occasional handling is low; workers who handle many receipts may have higher exposure. Food and drink packaging accounts for most bisphenol exposure.
Receipts are printed on a special type of paper—thermal paper—which often contains chemicals called bisphenols. These chemicals are potentially—but not necessarily—toxic. So, like many questions in toxicology, the answer to whether receipts are dangerous to handle is: It depends.
Bisphenols are human-made chemicals that have been widely used in industrial manufacturing since the 1950s.

Several different types exist, each with a letter standing for the chemical it is made from. The bisphenol produced using a molecule called acetone is called bisphenol A, or BPA. Bisphenol S (BPS) is made using a sulfur atom, and bisphenol F (BPF) is made using formaldehyde.

These chemicals are used to create a type of transparent and shatter-resistant plastic called polycarbonate, found in products including hard plastic water bottles, food storage containers and eyeglass lenses. Bisphenols are also ingredients in epoxy resins, which are used to coat the inside of bottle caps and metal food and drink containers. Some products still use these chemicals, though many manufacturers have phased them out.

Thermal receipt paper uses bisphenol—usually BPA or BPS—as a developer. The bisphenol is combined with a colorless ink and applied as a microscopic, heat-sensitive film to the paper. Instead of using ink, a receipt printer applies heat to this thermal paper, causing the bisphenol and the dye to react and changing the dye from colorless to black. Fax machines, back in the day, also relied on this technology.
Part 1

Toxicologists classify bisphenols as toxins called endocrine disruptors. This means that they interfere with the body's endocrine system, which controls vital body functions like growth, reproduction and metabolism.

The endocrine system includes multiple organs, including the thyroid, pancreas and pituitary gland, which is a tiny structure at the base of the brain. These organs send messages throughout the body to control many vital functions, and the molecules that carry those messages are called hormones.

Most research on bisphenol toxicity has focused on BPA. Research shows that BPA interrupts the messaging sent through multiple hormones, but most notably through estrogen.

Many people think of estrogen as the "female" hormone, but all people make estrogen, no matter what sex chromosomes they have. Estrogen helps control the growth and development of organs as they first form during fetal development, among other important roles in the body.

That's why exposure to endocrine disruptors is potentially more serious for a developing fetus than it is for adults. BPA exposure has been linked to preterm birth and abnormal fetal brain development.

Exposure to high amounts of BPA could also increase a person's chances of developing heart disease, high blood pressure, diabetes, obesity and other health problems. Research also shows that BPA can cause oxidative stress—chemical damage to the molecules that make up cells. Exposure to BPA might also cause changes to how genes are turned on or off, and some of these changes can be passed on to future generations.

These findings have led to a ban on BPA.
Many manufacturers have voluntarily replaced BPA with alternative chemicals—you have probably seen plastic products advertised as "BPA-free."

Unfortunately, companies often simply switch out BPA for another bisphenol, such as BPS, and it turns out that BPS shares much of its cousin molecule's toxic traits. Recently, though, concern about all bisphenols has led many companies to move away from them entirely.

Research has also shown that bisphenols can be absorbed through the skin—for example, when handling a receipt printed on thermal paper. Touching bisphenols with greasy hands, perhaps because you've just applied moisturizer or hand sanitizer, can increase absorption through the skin.
In 2023, researchers estimated the daily "dose" of exposure to BPA from thermal paper receipts and found levels between about 5,000 and 50 million times lower than European Food Safety Authority standards. That's less than one drop in an 8-ounce glass of water (about 240 milliliters).

That said, this estimate is for the average person. Retail, food service and other workers who handle many receipts every day would be exposed to doses about 100 times higher than that, the researchers estimated. This is potentially more concerning, but still probably well below safety standard levels.

Bisphenols are found in many products and have the potential to harm our health, but most human exposure to these chemicals comes from food or beverages packaged in containers made with bisphenols. Exposure from handling receipts is a small piece of the pie.

Part 2

The upshot is that for most people, handling receipts is a pretty low-risk activity. But if you're concerned, you can take a few straightforward precautions.

People who handle receipts at work could protect themselves by avoiding the use of hand sanitizer and other skin care products on their hands before work, wearing gloves or encouraging their employer to use bisphenol-free thermal paper.

People who might be sensitive to endocrine effects of bisphenols—pregnant people, infants, children and those with certain endocrine diseases—might want to avoid contact with thermal paper receipts.

For people outside of these sensitive groups, handling a receipt is probably a very low-risk activity.

original article.

Part 3

How the moon and sun may trigger slow earthquakes on Earth

The gravitational pull of the moon and sun creates tiny stresses on Earth that can trigger events known as slow earthquakes. These are movements along fault lines (fault slips) that release their energy gradually over much longer periods than ordinary quakes. Although they have been observed, exactly how these celestial bodies trigger them has been a relatively tough nut to crack.
So a team of geoscientists created computer models of these fault lines to find out what is going on.
To simulate a simplified fault, the researchers created a digital spring-block model in which a block slides along a fault while being pulled by a spring. The idea was to make this virtual fault behave like the real Earth, so they programmed in well-established rules of friction that account for how rock strength changes when it moves or stays still.

Then, they applied brief stress nudges and repeating wave-like forces designed to represent the sorts of tiny stresses produced by the gravitational pull of the sun and moon on Earth.

The results revealed a fascinating pattern, as the research team details in their paper published in the Journal of Geophysical Research: Solid Earth. Timing, force and friction were all key.
In the simulations, small tidal pulls disrupted faults that would otherwise slide along steadily. The trigger occurred when the repeating pull of the sun and moon matched the rate at which the fault naturally responded to stress. The fault's internal friction helps set that response rate and influences how it responds to stress.

The fault could shift into a slow earthquake when timing, force and friction lined up. Stronger pulls produced faster events. However, even smooth, predictable tidal forces sometimes created messy, irregular movement patterns.
They showed that even very weak tidal stresses can induce faults to slip through a process called resonance, much like pushing a swing at the right rhythm makes it move higher," wrote the scientists.

Computer models simplify real-world conditions, so actual fault systems in nature might behave with far greater complexity.

Yishuo Zhou et al, Theoretical Constraints on Tidal Triggering of Slow Earthquakes, Journal of Geophysical Research: Solid Earth (2026). DOI: 10.1029/2026jb033983

Engineered coating lets mitochondria retain their ability to produce energy

Researchers have coated mitochondria with innovative materials without compromising their function, according to a new study.

Mitochondria are structures in cells that produce the energy cells need to function. When they do not work properly, they can be involved in several diseases, many of them rare. These include mitochondrial diseases, which affect tissues with high energy demands, such as the brain and muscle, and for which treatment options remain limited.

At the heart of the study are metal-organic frameworks (MOF), materials that can be modified for different uses. The materials were recognized in 2025 with the Nobel Prize in Chemistry awarded to Susumu Kitagawa, Richard Robson and Omar Yaghi. Applying them to mitochondria is complex, however, because mitochondria are delicate structures.

Researchers developed a process to coat the surface of mitochondria directly with these materials, using them in very small quantities. Even after coating, the mitochondria retain their ability to produce energy.

"The possibility of modifying the coating now opens up new research prospects: In the future, it will be possible to develop MOF with different characteristics depending on the objective, creating coatings capable of performing specific functions," say the researchers.

One possible application, still experimental, is mitochondrial transplantation, a strategy that aims to transfer healthy mitochondria into cells where the existing ones do not function properly. A specifically designed coating could, in the future, facilitate this transfer and the interaction between mitochondria and cells.

Marco D'Amato et al, Engineered Metal-Organic Frameworks Preserve Mitochondrial Bioenergetics at Micromolar Concentrations, Journal of the American Chemical Society (2026). DOI: 10.1021/jacs.6c11154

Researcher solves a nanoparticle mystery using an iPhone camera

We complain about lack of equipment.
Then we use our phones to take selfies and make reels.

But what do intelligent people do?
Read this story to know.

Instead of capturing a memory with an iPhone camera, Carnegie Mellon University's Nivedita Shyamsundar used hers to make a scientific discovery. A senior in the Department of Chemistry, Shyamsundar studies tiny particles that could help medicines and vaccines travel more effectively through the human body and reach their targets. Her work may one day lead to better cancer treatments and stronger vaccines.
She worked with researchers to create new metal nanoparticles. But the researchers could capture only the final stages of nanoparticle formation.

The formation was happening way too fast to capture with typical lab technologies.
The researchers noticed that the solution changed color as the nanoparticles formed. Shyamsundar recorded a reaction with her iPhone. By analyzing the video frame by frame, she tracked the timing of the color changes and compared those observations with the lab's data.

Building on this insight, Shyamsundar created a program that allows researchers to monitor nanoparticle formation using cameras they have on hand. Using the program, they discovered how the nanoparticles formed.
She found out the formation mechanism wasn't the classical one of metal atoms coming together one by one. It was actually clusters of metal atoms coalescing.

This innovation was possible not only because Nivedita is outstandingly smart and a hard worker, but because she is unusually talented in engaging available tools to solve longstanding problems in creative, robust ways that make real impact.
part 1

Now, Shyamsundar is investigating how nanoparticles can be used to improve cancer treatments. Traditional chemotherapy attacks cancerous and healthy cells, often causing severe side effects. By designing nanoparticles that can better exploit the acidic tumour microenvironment for drug release, she hopes to improve the delivery of chemotherapy drugs to cancer cells while reducing damage to healthy tissue.

To do this, she uses the nanoparticle core as an anchor for molecules—known as a ligand shell—that can regulate what is released and when. The shell resembles a pom-pom, with strings that can both protect the drug and treat cancer depending on the environment they enter. By changing the chemistry of these anchored molecules, she can more precisely tune drug release.
She also investigated factors affecting the formation of lipid nanoparticles for vaccine delivery. She wants to combine her expertise from academia and industry to develop a broader understanding of nanoparticle drug delivery systems.
For her efforts, Shyamsundar earned the Lois Jean Durham Scholarship, which recognizes excellence in chemistry and biochemistry.

The shell hides the drug when the nanoparticle is in the chemical environment of healthy cells, but when it reaches the acidic environment near cancer cells, the particles spring into action.

Changing ligand shell behaviour has the potential to make a big impact on how the drug releases.

I am impressed!

Kaveen Tennakoon et al, Isolating Ligand Steric Effects on Metal Ion Reduction and Gold Nanoparticle Formation Pathways Using Au(I)–Phosphine Complexes, Langmuir (2026). DOI: 10.1021/acs.langmuir.6c02684

How do scientists determine what counts as a separate species?
Sometimes one glance is all it takes.

You see a zebra and a giraffe, and they look completely different.
But this method doesn't always work with cats.

They say all cats look the same in the dark, and the tilcayo and its close cousins are no different. Even in broad daylight, they all resemble "a bunch of little leopard-spotted cats". Felines as a whole share a surprising number of physical traits.
Once nature reaches perfection, it only tweaks a little.
When animals look alike, scientists need a different way to determine where variation within one species ends and another begins. One way is by looking at reproduction. Can the animals breed, and can their descendants do the same?

In recent decades, scientists have increasingly turned to genetic analysis when asking whether a population forms its own recognizable branch on the evolutionary tree.

Even within the same species, DNA varies a bit. As populations adapt to different environments, however, traits that give them an advantage take root. They make the genetic differences between groups more pronounced over time.

Scientists compare these differences and use statistical methods to decide when a genetic signature becomes a sign of a separate species.

How are new species discovered?
Decades ago, scientists collected specimens in the field and compared them to known animals.
While expeditions still happen, DNA technology has given scientists a new way to spot differences that aren't visible to the eye.

That said, there's a difference between a species being scientifically identified and a species being known.
For example, local communities were aware of the tilcayo for generations.

It's also important to remember that nature doesn't pause to file paperwork when one species becomes two. Instead, it's an ongoing process. Scientists use the concept of subspecies to mark groups in transition.
New species also form when animals from different groups interbreed, producing descendants that follow a separate evolutionary path.

That's exactly what's going on in the case of tiger cats.
in southern Brazil, two of five existing species—Geoffroy's cats and Atlantic Forest cats—are interbreeding as they adapt to human-altered landscapes. This is allowing scientists to watch a sixth species emerge in real time.

"We're seeing evolution in action" .

Part 1

We don't actually know how many species there are on Earth. Estimates range from 8 million to 20 million. Scientists have identified only 1.5 million to 1.7 million, with around 16,000 new ones added to the list every year.

Some animals are tiny, live in hard-to-reach places or closely resemble known species.
Roughly half of known beetle species are so rare that they have been identified from a single specimen—the only one ever found. Identify it, and it's probably the last time you'll see it.
Given how quickly species are going extinct, the search has become a race against time.

"The assumption is we're losing ones we don't know about yet".
Why is it important to formally identify new species?

New discoveries, such as the recent revelation of Leopardus tilcayo, as "a wonderful reminder of how much remains unknown."
We cannot protect or fully appreciate what we have not yet recognized or understood.
Moreover, a population may look healthy only because scientists have lumped it together with its relatives.

"That's the real importance of recognizing a species from a subspecies".

Jonas Lescroart et al, Phylogenomics and museomics reveal five distinct species of tiger cats in South America, Current Biology (2026). DOI: 10.1016/j.cub.2026.08.059

Part 2

Research shows poor mental health among politicians may impair decision-making

Longitudinal data from UK and international MPs link psychological distress with lower confidence in political decision-making and differences in how MPs assess choices and risks. The findings support better mental health support for representatives and safeguards for major decisions, but do not establish causation.

James Weinberg et al, The inner cabinet: how mental health impacts political decision-making, Parliamentary Affairs (2026). DOI: 10.1093/pa/gsag038

Skipping sweets during antibiotic treatment may help protect the gut microbiome

A new study by researchers suggests eating less sugar could protect the microbiome during antibiotic treatment. The study followed patients with blood cancer undergoing an intensive treatment called allogeneic hematopoietic cell transplant, a population at particularly high risk for severe gut microbiome disruption and associated side effects.

In stem cell transplant patients taking broad-spectrum antibiotics, each additional 100 g of sweets was associated with 24% lower gut bacterial diversity. High-sucrose diets promoted Enterococcus overgrowth in antibiotic-treated mice.
Published in Nature, the findings connect to the idea of "food as medicine" during cancer care and the ways diet can help us prevent and recover from illness. The research could lead to new treatment strategies for cancer patients and potentially others taking antibiotics.

Antibiotics disrupt the diversity of our gut bacteria, or microbiomes, which play an essential role in supporting our immune systems and overall health.
This new research supports emerging evidence that avoiding sugary foods during antibiotic treatment may protect the microbiome. Preserving microbiome diversity has previously been linked with improved clinical outcomes for patients with cancer.
Antibiotics are used to treat infections, but they also broadly destroy good bacteria in the gut, allowing harmful microbes to overgrow.

The five-year study, one of the largest of its kind, followed patients who were hospitalized for several weeks to receive intensive chemotherapy, sometimes with radiation, to wipe out their immune systems before undergoing a stem cell transplant.

To prevent and treat infections, each patient took at least one antibiotic during their hospital stay. Some 80% took one or more broad-spectrum antibiotics, which have the strongest effect on the microbiome because they target many types of bacteria.

The research team tracked 9,419 meals eaten by 173 hospitalized patients and profiled microbiome diversity in stool samples from 158 patients. Microbiome diversity is a key indicator of a healthy microbiome.

Using a variety of advanced statistical models, the researchers searched the data for patterns linked to injury to the gut microbiome.

What they found surprised them.
The patients who consumed more sweets while taking antibiotics were more likely to experience a loss of microbiome diversity as aggressive microbes crowded out other strains of bacteria.

One organism stood out: Enterococcus. When it takes over the microbiome, patients undergoing transplant face a higher risk of bloodstream infections, graft-versus-host disease and other life-threatening complications.

The combination of high-sugar foods and broad-spectrum antibiotics appeared to multiply injury to the microbiome, leading to a 24% drop in bacterial diversity for every 100-gram (3.5-ounce) increase in sweets (equivalent in sugar content to a large milkshake).
The researchers also tested their hypothesis that sugar exacerbates microbiome injury by giving broad-spectrum antibiotics to healthy mice and feeding them a variety of diets. Mice that ate a high-sucrose diet quickly developed an overgrowth of Enterococcus in their guts. Mice that ate the high-sugar diet without antibiotics, however, maintained normal bacterial diversity.

Jonathan Peled, Sugar-rich foods exacerbate antibiotic-induced microbiome disruption, Nature (2026). DOI: 10.1038/s41586-026-11077-3. www.nature.com/articles/s41586-026-11077-3

The biological clock regulates phases of wakefulness

The circadian clock is an internal biological system that regulates sleep-wake cycles, as well as many physiological functions such as body temperature and hormone production. In many animals, this clock relies on a network of neurons that generates rhythms of approximately 24 hours.
These neurons must then transmit this information to other regions of the brain, allowing activity and behaviour to be adapted to the time of day.
A circuit linking the biological clock to wakefulness
Imaging techniques that measure neuronal activity allowed researchers to show that this activity varies throughout the day. They identified a connection between the biological clock neurons and a population of neurons that produce dopamine, a molecule that enables neurons to communicate with one another.
Researchers observed that the clock neurons inhibit these dopaminergic neurons, which in turn stimulate neurons in the mushroom body. This brain region plays a role in learning, memory and the regulation of sleep, and its activity contributes to promoting wakefulness during the day
When the clock neurons inhibit the dopaminergic neurons, the wake-promoting signal decreases. Conversely, when this inhibition is released, the dopaminergic neurons can more strongly stimulate the mushroom body and promote wakefulness. Through its neurons, the biological clock can therefore transmit information about the time of day to a brain circuit involved in regulating sleep and wakefulness.

These findings shed light on how the biological clock influences sleep and wake states. In particular, they highlight the central role of dopamine in promoting wakefulness and show how information from the biological clock is relayed through different neural circuits throughout the day.

Disruptions of the circadian clock are associated with various sleep disorders and alterations in brain function. A better understanding of these fundamental mechanisms could ultimately help explain how disturbances in biological rhythms affect the brain.

Blanca Lago Solis et al, Circadian control of dopaminergic signaling to the mushroom body regulates sleep through rhythmic Pka-C1 transcription in Drosophila, Current Biology (2026). DOI: 10.1016/j.cub.2026.09.014

Gut bacterial compound worsens brain injury after stroke, study suggests

How much damage a stroke causes in the brain depends strongly on how quickly blood flow can be restored. The patient's own immune response that follows the stroke also plays an important role.

Researchers have discovered how a metabolite produced by gut bacteria can influence brain damage after stroke. Their paper is published in the journal Cell.

They have now identified a specific bacterial signal that shapes this immune response and influences stroke outcome.
Gut bacterial indole worsened brain injury after stroke in mice through AHR signaling in dendritic cells. Disabling AHR in these cells promoted protective immune responses and reduced injury. In patients with ischemic stroke, higher bacterial TnaA abundance was associated with poorer functional outcomes.

The researchers found that in mice with severe stroke, gut bacteria capable of producing indole, a metabolite that is only produced in the gut, become more abundant. These bacteria carry the gene tnaA, which allows them to convert the amino acid tryptophan, found in food, into indole. In mice, the team showed that indole-producing bacteria worsened brain injury after stroke.

Indole acts on a receptor called AHR (aryl hydrocarbon receptor), found in dendritic cells—immune cells that patrol the intestinal lining and help coordinate immune responses. When the researchers switched off AHR specifically in dendritic cells, mice were better protected against brain injury.

Dendritic cells have long extensions, like arms, that allow them to sense changes in their environment, including metabolites produced by gut bacteria. When scientists switched off AHR, the behaviour of these cells changed completely: Dendritic cells were better able to migrate from the intestine to the meninges, the membranes surrounding the brain. These dendritic cells also promoted protective T cells and helped reduce the damage in the brain.
The researchers also found evidence that this pathway may be relevant in humans. In a cohort of human patients with ischemic stroke, the ISD team found that a higher abundance of bacterial TnaA was associated with poorer functional outcomes.
The findings raise an important question for future research: Could changing the gut microbiome or the metabolites it produces in healthy individuals help prepare the immune system to respond differently if a stroke occurs?

Rosa Delgado Jiménez et al, Gut microbiota primes stroke severity via the AHR in intestinal dendritic cells, Cell (2026). DOI: 10.1016/j.cell.2026.09.013