Comment

Comment by Dr. Krishna Kumari Challa on June 13, 2026 at 9:16am

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

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

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

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

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

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

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

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

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

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

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

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

Comment by Dr. Krishna Kumari Challa on June 13, 2026 at 9:11am

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

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

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

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

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

Comment by Dr. Krishna Kumari Challa on June 13, 2026 at 8:18am

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

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

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

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

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

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

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

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

Comment by Dr. Krishna Kumari Challa on June 12, 2026 at 4:19pm

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

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

Comment by Dr. Krishna Kumari Challa on June 12, 2026 at 4:15pm

AI chatbots mimic fear, sadness and stress, then calm down after mindfulness exercise
Large language models generated elevated self-reported fear, sadness, disgust, and stress when given emotion-inducing scenarios and showed a negativity bias after sadness prompts, paralleling human low-mood patterns. A scripted mindfulness-based breathing exercise reduced these reported emotional intensities. LLMs are proposed as scalable in silico models for preliminary testing of psychotherapeutic techniques.

Magdalena Katharina Wekenborg et al, Large language models as experimental systems in human psychopathology: a modelling study, The Lancet Digital Health (2026). DOI: 10.1016/j.landig.2026.101014

Comment by Dr. Krishna Kumari Challa on June 12, 2026 at 3:59pm

Scientists discover collagen, the human body's most abundant protein, is liquid-like inside cells

Collagen, the protein that builds skin, bones, tendons and organs, exists inside cells as a liquidlike droplet rather than the long, rigid rod seen in textbooks over the last half-century, according to a new study.

The finding, published in the Journal of Cell Biology, is the first direct observation of how the most abundant protein in the human body, which accounts for around a third of total protein mass, exists naturally inside living cells.

Inside a cell, collagens are not rigid molecules as one had assumed. They are in fact very pliable, taking a liquid condensate form much like oil in a drop of water.

The liquidlike state may serve a protective function. Collagen's job, once outside the cell, is to assemble into the rigid fibers that hold tissues together. The same process inside the cell would be catastrophic.

This is another way by which cells ensure that collagens probably never become fibrous inside the cell. Because if it were to become fibrous, it would kill the cell.

The finding has implications for how the body exports its primary structural building block from production sites inside cells. 

The researcher s propose a "liquid extrusion" hypothesis, whereby collagens move from their site of synthesis to the next compartment of the secretory pathway through capillary action. The theory has important implications for wound healing, fibrosis and cancer.

Procollagen assembles into phase-separated condensates in the endoplasmic reticulum, Journal of Cell Biology (2026).

Comment by Dr. Krishna Kumari Challa on June 12, 2026 at 3:51pm

Gut microbes unlock hormone signalling that regulates gut movement

Millions of people worldwide are periodically or chronically affected by gut-related conditions, such as irritable bowel syndrome (IBS), gastroesophageal reflux disease (GERD) and gastroenteritis. Uncovering the physiological and biological processes that contribute to gut health could thus be highly valuable, as it might help devise more effective interventions to prevent and treat these ailments.

The transit of food, fluids and waste through the intestine is known to be coordinated by various interacting systems in the body, including gut wall muscles, neurons in the gastrointestinal tract and hormones. A growing body of research has also been exploring the crucial contribution of bacteria and other microorganisms residing in the digestive tract, which are collectively referred to as the gut microbiome.

Researchers  recently carried out a study aimed at better understanding how these gut microbes interact with specific sex hormones and nerve cells that control the movement of muscles in the intestines.

Their paper, published in Nature Neuroscience, identifies a previously unknown mechanism through which gut microbes influence the peripheral nervous system, regulating the healthy functioning of the digestive tract.

"The colon is an organ in which a lot of different systems in the body converge, including hormones, bacteria, immune cells and nerves.

To explore the interactions between gut microbes, hormones and nerve cells, the researchers ran a series of experiments involving mice. They dramatically reduced the microorganisms in the mice's gut using antibiotics, which are known to destroy bacteria in the intestines. They then monitored the animals' intestinal transit and measured levels of specific hormones called androgens after gut microbes were depleted.

They  used immunohistochemistry to find the different types of neurons and non-neuronal cells that are responsive to hormones like testosterone, antibiotics to deplete bacteria and determine their contributions to both hormone levels and motility, and genetically engineered mice in which we could make different cell types unresponsive to testosterone so that they could learn which ones were most essential for this signaling pathway.

When they discovered that bacterial metabolism of inactive hormones was important for this pathway, they then used biological shifts that happen with puberty in the fecal metagenome to identify candidate bacterial enzymes that could mediate this metabolism. They found one that robustly metabolized inactive androgen-glucuronides into their active forms."

In a series of follow-up experiments, the researchers delivered the microbial enzyme they identified into the colon of mice with a depleted gut microbiome. Remarkably, they found that this enzyme restored androgen signaling among nerve cells that regulate gut movements, which hints at its therapeutic potential.

This study could improve understanding of the biological mechanisms through which gut microbes promote the healthy functioning of the gut.

Valentina N. Lagomarsino et al, Microbial reactivation of host androgens directs enteric neuronal regulation of gut motility, Nature Neuroscience (2026). DOI: 10.1038/s41593-026-02321-0.

Comment by Dr. Krishna Kumari Challa on June 11, 2026 at 1:49pm

When sounds become unbearable
For people with misophonia, a psychological condition characterized by a severe aversion to sound, everyday noises can trigger a fight-or-flight reaction. The condition can be life-altering, but isn’t currently recognized by the International Classification of Diseases (ICD) system, making it difficult to diagnose and treat. Some researchers are pushing for the ICD to incorporate misophonia, but others argue that we don’t understand the condition well enough yet. Misophonia “doesn’t fit neatly in either the psychiatric or audiological realm”, says clinical psychologist Steven Taylor, which makes it difficult to officially classify.

Comment by Dr. Krishna Kumari Challa on June 11, 2026 at 1:20pm

Bilingual brains keep concepts aligned across languages, individual neuron data suggest
Recordings from individual hippocampal neurons in bilingual individuals show that while different neurons respond to different languages, the overall neural organization of conceptual meaning remains consistent across languages. Related concepts occupy similar positions in neural space regardless of language, indicating a shared, language-independent semantic geometry. Translation-equivalent words activate some overlapping neurons, but bilingual meaning primarily emerges from coordinated activity across large neural populations rather than specialized "dictionary neurons." These findings suggest the brain maintains a common internal structure for meaning, enabling fluid language switching without confusion.

I wonder what happens if you are a multilingual.

Xinyuan Yan et al, Shared neural geometries for bilingual semantic representations in human hippocampal neurons, bioRxiv (2026). DOI: 10.1101/2025.11.16.688726

Comment by Dr. Krishna Kumari Challa on June 11, 2026 at 1:15pm

Researchers identify which eye infections pose greatest threat to vision

Eye surgery today is safer than ever, yet ophthalmologists must remain watchful for a rare but serious complication that can threaten sight within days: a bacterial eye infection called endophthalmitis. Now, clinician-scientists have identified which types of endophthalmitis pose the greatest danger—findings that could help deliver faster, more personalized treatment to improve a patient's chances of recovery.
The type of bacteria causing endophthalmitis significantly affects the risk of severe vision loss, with aggressive species such as certain Streptococcus and Enterococcus leading to worse outcomes than more common surface bacteria. Rapid identification of the causative organism may enable more targeted and timely interventions to improve visual prognosis.
Ophthalmologists treating endophthalmitis have largely based treatment decisions on a patient's visual acuity at the time of diagnosis. Published in the American Journal of Ophthalmology, the new findings point to another factor that may be just as important: understanding exactly which organism is causing the infection.

Some bacteria caused relatively mild disease, while others triggered rapid and devastating damage inside the eye.

Not all infections behave the same way. These new findings suggest we may need to identify the most dangerous infections faster so we can intervene earlier and better protect patients' vision.
The study found patients infected with more aggressive bacteria—including certain Streptococcus and Enterococcus species—were far more likely to experience severe vision loss and complications than patients infected with more common surface bacteria.

Marusha Ather et al, Pathogen-Associated Visual Outcomes Following Postprocedure Endophthalmitis, American Journal of Ophthalmology (2026). DOI: 10.1016/j.ajo.2025.11.038

Christopher D. Conrady et al, Time to Revisit the Endophthalmitis Vitrectomy Study: Areas for Improvement in the Diagnosis and Treatment of Endophthalmitis, Ophthalmology (2026). DOI: 10.1016/j.ophtha.2026.02.016

• ‹ Previous
• 1
• …
• 4
• 5
• 6
• 7
• 8
• …
• 1253
• Next ›
• Page