Science Simplified!

                       JAI VIGNAN

All about Science - to remove misconceptions and encourage scientific temper

Communicating science to the common people

'To make  them see the world differently through the beautiful lense of  science'

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  • Dr. Krishna Kumari Challa

    The team also has a theory as to how WHG genes may help people live to a ripe old age. They suggest that these variants were selected during the last Ice Age, when our ancestors had to survive extremely harsh conditions with limited food resources. The scientists think these genes helped improve metabolism to process food more efficiently and strengthen the immune system to protect the body from age-related stresses.

    Stefania Sarno et al, Western Hunter-Gatherer genetic ancestry contributes to human longevity in the Italian population, GeroScience (2025). DOI: 10.1007/s11357-025-02043-4

    Part 2

  • Dr. Krishna Kumari Challa

    Grok spews misinformation about deadly Australia shooting
    Grok, an AI chatbot, disseminated multiple false claims during the Bondi Beach mass shooting in Australia, including misidentifying a hero, mislabeling images, and suggesting a survivor staged his injuries. These errors highlight the limitations of AI chatbots in real-time fact-checking, especially during rapidly evolving news events, and underscore the continued need for human oversight.

    Source: News agencies

  • Dr. Krishna Kumari Challa

    HOW THE BRAIN MEASURES DISTANCE OF A FAMILIAR PLACE IN THE DARK

    Whether you are heading to bed or toilet of your home in the dark, you don't need to turn on the lights to know where you are as you walk through your house at night. This hidden skill comes from a remarkable ability called path integration: your brain constantly tallies your steps and turns, allowing you to mentally track your position like a personal GPS. You're building a map by tracking movement, not sight.
    Scientists think that understanding how the brain performs path integration could be a critical step toward understanding how our brain turns momentary experiences into memories of events that unfold over time.
    In their study, the team trained mice to run a specific distance in a gray virtual reality environment without visual landmarks, in exchange for a reward. The animals could only judge how far they had traveled by monitoring their own movement, not by relying on environmental cues.

    As mice performed this task, the scientists recorded tiny electrical pulses that neurons use to communicate, allowing them to observe the activity of thousands of neurons.

    They focused on the activity of neurons in the hippocampus, a region essential for both navigation and memory. Using computer modeling, they then analyzed these signals to reveal the computational rules the brain uses for path integration.
    The hippocampus is known to help animals find their way through the environment. In this brain region, some neurons become active at specific places. However, in environments full of sights, sounds, and smells, it is difficult to tell whether these neurons are responding to those sensory cues or to the animal's position itself.
    The scientists discovered that during navigation without landmarks, most hippocampal neurons followed one of two opposite patterns of activity. These patterns were crucial for helping the animals keep track of how far they had traveled.

    In one group of neurons, activity sharply increased when the animal started moving, as if marking the start of the distance-counting process. The activity of these neurons then gradually ramped down at different rates as the animal moved further, until reaching the set distance for a reward.

    A second group of neurons showed the opposite pattern. Their activity dropped when the animal started moving, but gradually ramped up as the animal traveled farther.

    The team discovered that these activity patterns act as a neural code for distance, with two distinct phases. The first phase (the rapid change in neural activity) marks the start of movement and the beginning of distance counting. The second phase (the gradual ramping changes in neural activity) counts the distance traveled. Both short and long distances could be tracked in the brain by using neurons with different ramping speeds.
    The scientists have discovered that the brain encodes the elapsed distance or time needed to solve this task using neurons that show ramping activity patterns.
    This is the first time distance has been shown to be encoded in a way that differs from the well-known place-based coding in the hippocampus. These findings expand our understanding that the hippocampus is using multiple strategies—ramping patterns in addition to the place-based coding—to encode elapsed time and distance."

    When the researchers disrupted these patterns by manipulating the circuits that produce them, the animals had difficulty performing the task accurately and often searched for the reward in the wrong location.

    Time or distance encoding by hippocampal neurons via heterogeneous ramping rates, Nature Communications (2025). DOI: 10.1038/s41467-025-67038-3

  • Dr. Krishna Kumari Challa

    Chronic fatigue syndrome linked to widespread energy, immune and vascular changes
    People with ME/CFS exhibit concurrent abnormalities in cellular energy metabolism, immune cell maturity, and plasma proteins linked to vascular dysfunction. Elevated AMP and ADP levels indicate impaired ATP production, while immune profiling shows less mature lymphocyte subsets. Machine learning identified seven biological markers strongly associated with ME/CFS.

    Key findings of a multimodal study published in the journal Cell Reports Medicine include changes in markers of cellular energy metabolism, in the proportions and maturity of circulating immune cells, and in plasma proteins associated with blood vessel dysfunction in people with ME/CFS.

    Led by researchers from Macquarie University, the study compared whole blood samples from 61 people meeting clinical diagnostic criteria for ME/CFS with samples from healthy age- and sex-matched volunteers.

    Cellular and immune system changes
    White blood cells from ME/CFS patients showed evidence of "energy stress" in the form of higher levels of adenosine monophosphate (AMP) and adenosine diphosphate (ADP), indicating reduced generation of adenosine triphosphate (ATP), the key energy source within cells.

    Profiling of immune cell populations revealed a trend toward less mature subsets of T-lymphocyte subsets, dendritic cells and natural killer cells in people with ME/CFS.

    Comprehensive analysis of plasma proteins highlighted disruptions of vascular and immune homeostasis in patients with ME/CFS. Levels of proteins associated with activation of the endothelium—the innermost lining of blood vessels—and remodeling of vessel walls were higher, while levels of circulating immunoglobulin-related proteins were lower.

    Benjamin Heng et al, Mapping the complexity of ME/CFS: Evidence for abnormal energy metabolism, altered immune profile, and vascular dysfunction, Cell Reports Medicine (2025). DOI: 10.1016/j.xcrm.2025.102514

  • Dr. Krishna Kumari Challa

    How embryos and the uterus 'talk' during implantation

    Implantation is one of the most delicate and failure-prone stages of pregnancy in humans and other animals.

    A new study shows that the embryo and the uterine lining conduct an active "conversation" from the very earliest stages of implantation. They engage in a back and forth of tiny packages called extracellular vesicles and lipid droplets, which carry metabolites and signals. Hormones determine what the uterus sends, and one signaling pathway (related to aryl hydrocarbon receptor, [AhR]) appears to assist in determining how hospitable the uterine environment is.

    When this pathway is blocked, embryos attach more strongly. These packages are taken up quickly; their genetic material is used almost immediately, they influence how cells use energy and handle fats, and they reshape the uterine tissue—all in ways that support embryo attachment and implantation.

    Published in The Journal of Extracellular Vesicles, the research uncovers a previously underappreciated communication network between the early embryo and the uterus, which may be critical for successful implantation and early pregnancy. The study reveals how extracellular vesicles, lipid droplets, and AhR ligands dynamically interact during the earliest stages of embryo-maternal crosstalk.

    Alisa Komsky‐Elbaz et al, Extracellular Vesicles, Lipid Droplets and AhR Ligands in Early Implantation: The Dynamics of Embryo‐Maternal Crosstalk, Journal of Extracellular Vesicles (2025). DOI: 10.1002/jev2.70161

  • Dr. Krishna Kumari Challa

    Sick, Immobile Young Ants Send “Kill Me” Signal to Colony Workers

    Cocooned ants infected with a deadly fungus call on workers to kill them to protect the colony—the first example of altruistic disease signaling in social insects.

    Adult ants that have been infected with deadly pathogens often leave the colony to die so as not to infect others. But, like infected cells in tissue, young ants are largely immobile and lack this option.

    Invasive garden ant pupae that have been infected with a deadly fungal pathogen produced chemicals that induced worker ants to unpack their cocoons and kill them, preventing the disease from spreading to the rest of the colony.

    In a new study, researchers discovered that the infected pupae only released chemicals when there were workers nearby, suggesting that the sick young ants put these events in motion. The researchers’ findings, published in Nature Communications, are the first evidence of altruistic disease signaling in a social insects and share similarities with how sick and dying cells send a “find me and eat me” signal to the immune system.

    Infected pupae consistently upregulated immune genes upon infection, regardless of whether workers were around. However, changes in the level of specific CHCs only occurred when the pupae were infected and workers were nearby. Furthermore, the team found that when they coated healthy pupae with extracts from infected pupae, workers unpacked the healthy pupae more frequently than healthy pupae covered in “non-signal” extracts. Altogether, these observations indicate that infected pupae likely release specific CHCs so workers could find and kill them, which means that these young ants sacrifice themselves to benefit the colony.

    1. Pull CD, et al. Destructive disinfection of infected brood prevents systemic diseas.... Elife. 2018;7:e32073.
    2. Dawson EH, et al. Altruistic disease signalling in ant colonies. Nat Commun. 2025;16:10511.
    3. Kugelberg E. Cell death: Find me and eat me. Nat Rev Immunol. 2016;16(3):131.
  • Dr. Krishna Kumari Challa

    AI-designed antibodies race toward trials
    Scientists say they are on the cusp of turning antibodies designed by artificial intelligence into potential therapies, just a year after they debuted the first example of an entirely AI-designed antibody. Previously, the structure of antibodies proved somewhat of a black box to AI models. But new and improved models — such as an updated version of AlphaFold — have more successfully predicted the shape of flexible structures that give antibodies the specificity they need to bind to foreign molecules. Researchers at several companies now say they’ve designed ‘drug-like’ antibodies.

    https://www.nature.com/articles/d41586-025-03965-x?utm_source=Live+...

  • Dr. Krishna Kumari Challa

    Scientists build a quantum computer that can repair itself using recycled atoms

    Like their conventional counterparts, quantum computers can also break down. They can sometimes lose the atoms they manipulate to function, which can stop calculations dead in their tracks. But scientists have demonstrated a solution that allows a quantum computer to repair itself while it's still running.

    The research team zeroed in on quantum computers that use neutral atoms (atoms with equal numbers of protons and electrons). These individual atoms are the qubits, or the basic building blocks of a quantum computer's memory. They are held in place by laser beams called optical tweezers, but the setup is not foolproof.

    Occasionally, an atom slips out of its trap and disappears. When this happens mid-calculation, the whole process can grind to a halt because the computer can't function with a missing part.

    In a paper published in the journal Physical Review X, the researchers detail how they solved this problem by rearranging the atoms within the machine. Instead of having all the atoms in a single crowded group, the team organized them into five distinct zones. This means that if an atom is lost in one part of the computer, the other qubits will not be affected.

    The specialized zones are a "Register" for storing qubits, an "Interaction Zone" for performing calculations and a "Measurement zone" for checking errors using helper atoms known as "ancillas." There is also a "Storage Zone," a reservoir of spare atoms to replace those that are lost and a "Loading Zone' to bring in new atoms from the outside to refill the reservoir.

    But the solution is even more sophisticated than that. This neutral atom-based quantum computer can detect a breakdown and fix it on the fly. When the system notices a missing qubit, it reaches into the storage zone and moves a new atom into place.

    Once this atom is in position, the computer prepares it for work by resetting it to its ground state (lowest-energy state). The computer can also recycle the ancillas once they have performed their checks by resetting them in the same way.

    To demonstrate that their solution works, the study authors had the computer run a repetition code, a process that checks its own work for mistakes. They ran these checks 41 times in a row, and each time, the machine successfully replaced its lost atoms without disturbing the data being processed. Without this self-repairing ability, the system would have run out of atoms after a few rounds.

    J. A. Muniz et al, Repeated Ancilla Reuse for Logical Computation on a Neutral Atom Quantum Computer, Physical Review X (2025). DOI: 10.1103/v7ny-fg31

  • Dr. Krishna Kumari Challa

    Life on lava: How microbes colonize new habitats

    Life has a way of bouncing back, even after catastrophic events like forest fires or volcanic eruptions. While nature's resilience to natural disasters has long been recognized, not much is known about how organisms colonize brand-new habitats for the first time. A new study  by a team of ecologists and planetary scientists provides glimpses into a poorly understood process.

    The team conducted field research in Iceland following a series of eruptions of the Fagradalsfjall volcano, located on the southwestern tip of the island. The volcano erupted for a total of three times over the course of the study period, from 2021 until 2023. With each eruption, lava flows blanketed the tundra around the volcano, in some places even covering lava deposits from the previous year.

    The lava coming out of the ground is over 2,000 degrees Fahrenheit, so obviously it is completely sterile. It's a clean slate that essentially provides a natural laboratory to understand how microbes are colonizing it.

    To untangle the ecological dynamics involved in that process,  the team searched for clues about where the microbes that colonize fresh lava come from. They collected samples from a variety of different potential sources, including lava that had solidified mere hours before, rainwater, and aerosols—particles floating in the air. For context, they sampled soil and rocks from surrounding areas.

    The researchers then extracted DNA from these samples and used sophisticated statistical and machine learning techniques to identify the organisms present on freshly imposed lava flows, the composition of these micro-habitats and where they originated.

    The work revealed that as microbes colonized the new habitat, biodiversity increased over the course of the first year following an eruption. But after the first winter, diversity "tanked',  probably because the seasonal shifts in environmental conditions were selecting for a specific subset that could survive those conditions. With each subsequent winter, the analyses revealed less turnover and showed that diversity stabilized over time. With all these data, a picture began to emerge.

    It appears that the first colonizers are these 'badass' microbes, for lack of a better term, the ones that can survive these initial conditions, the researchers say, "because there's not a lot of water and there's very little nutrients. Even when it rains, these rocks dry out really fast.

    Over the next several months and seasonal shifts, the study revealed, the microbial community begins to stabilize, as more microbes are added with rainwater and "moved in" from adjacent areas.

    Part 1

  • Dr. Krishna Kumari Challa

    A major finding of the study pointed to rainwater playing a critical role in shaping microbial communities on freshly deposited lava, according to the researchers.

    Early on, it appears colonizers are mostly coming from soil that is blown onto the lava surface, as well as aerosols being deposited. But later, after that winter shift in diversity they observed, they saw most of the microbes are coming from rainwater, and that's a pretty interesting result.

    Scientists have long known that rainwater is not sterile; microbes in the atmosphere, either free floating or attached to dust particles, can even function as cloud condensation nuclei, which are microscopic particles that offer water vapor a surface to latch on to and grow into tiny droplets. In other words, tiny, invisible creatures may play outsized roles in weather and climate phenomena.

    Nathan Hadland et al, Three eruptions at the Fagradalsfjall Volcano in Iceland show rapid and predictable microbial community establishment, Communications Biology (2025). DOI: 10.1038/s42003-025-09044-1

    Part 2

  • Dr. Krishna Kumari Challa

    Can 'miracle' heaters really warm your home for pennies? The physics says no


    Claims that portable electric heaters can heat homes for pennies or rapidly warm entire houses are not supported by physics. All electric heaters are nearly 100% efficient, meaning almost all input electricity becomes heat, but this does not make them cheap to run. No plug-in heater can outperform others in efficiency or safely deliver enough power to heat a whole house quickly. Heat pumps offer greater efficiency by moving heat rather than generating it, but are costly to install. Effective home heating relies on better insulation, efficient systems, and affordable energy, not miracle devices.

  • Dr. Krishna Kumari Challa

    Urban birds' beak shape rapidly changed during COVID-19 lockdowns, suggesting human-driven transformations
    During the COVID-19 lockdowns, urban dark-eyed juncos developed longer, thinner beaks resembling their wild counterparts, likely due to reduced human food waste. As human activity resumed, beak shapes reverted to the shorter, thicker form typical of urban birds. These rapid, reversible changes highlight the strong influence of human presence on urban bird morphology.

    When the world slowed down during the COVID-19 pandemic, its effects extended beyond humans. A recent study found that it reshaped urban ecosystems to such an extent that certain city-dwelling birds even began to develop longer, thinner beaks resembling those of their wild relatives.

    The dark-eyed junco is a small, grayish songbird that is a common winter guest across North America.

    A research duo from the University of California, Los Angeles, identified that the juncos living on campus were an ideal system for exploring how physical traits change in urban environments. They tracked changes in the birds across the pre-pandemic and post-pandemic periods, from 2018 to 2025.

    They observed that birds that hatched during the pandemic, when the campuses became empty and there was less food waste to feed on, had beaks with higher bill length and slimmer structure, similar to the wildland birds. However, after the COVID-19 restrictions were lifted and people started trickling back to campus and food waste became ample. Birds born during this period reflected this shift, exhibiting shorter, thicker beaks typical of urban juncos.

    Studies have shown that animals living in cities can undergo rapid phenotypic changes — observable alterations in an organism's traits or characteristics—in response to newer environments, necessary to increase their chances of survival and the urban setting.

    The juncos living in California, U.S. are no longer winter visitors, they have become year-round residents over the past few decades. As a result, these birds appear to have adapted to urban life by evolving physical traits that help them thrive in city landscapes.

    One of the most striking changes is in their beaks. Juncos living in Los Angeles have shorter, thicker beaks than those found in local mountainous forests. Scientists think that this change might be linked to their diet, which now includes human food waste rather than the seeds, worms, and insects that wild juncos typically eat.

    The period of global slowdown caused by COVID-19 lockdowns, now known as the anthropause, gave scientists a rare chance to see how animals physically changed when human activity suddenly decreased.

    Part1

  • Dr. Krishna Kumari Challa

    the researchers found that the anthropause corresponded with changes in bill shape and size. Birds hatched during the pandemic had beaks similar to wild juncos, but as human activity picked up again, their beaks reverted to the short, stout form seen in urban populations. These results indicate that city birds quickly adjusted their behavior when human activity stopped and started again.

    The researchers note that further genetic and behavioral studies in both urban and wildland populations are needed to confirm whether these shifts were driven by genetic changes triggered by low human activity or temporary movements of wild birds into the city during the pandemic.

     Eleanor S. Diamant et al, Rapid morphological change in an urban bird due to COVID-19 restrictions, Proceedings of the National Academy of Sciences (2025). DOI: 10.1073/pnas.2520996122

    **

    Part 2

  • Dr. Krishna Kumari Challa

    Mitochondria migrate toward the cell membrane in response to high glucose levels, study shows
    In pancreatic beta cells, high glucose levels cause mitochondria to migrate toward the cell periphery. This movement depends on intact microtubules and cAMP signaling, but not on mitochondrial ATP production. Peripheral redistribution of mitochondria may influence insulin secretion, suggesting spatial organization of mitochondria is important for beta cell function.

     Mitochondrial position responds to glucose stimulation in a model of the pancreatic beta cell, Biophysical Journal (2025). DOI: 10.1016/j.bpj.2025.11.018www.cell.com/biophysj/fulltext … 0006-3495(25)00767-2

  • Dr. Krishna Kumari Challa

    Bacterium hijacks fruit ripening program in citrus plants to steal sugars, research reveals
    Xanthomonas citri, the causative agent of citrus canker, manipulates citrus leaf cells by activating a fruit ripening program, leading to the release of cell wall-bound sugars that fuel rapid bacterial growth. This process mimics natural fruit ripening at the genetic level and highlights a mechanism by which pathogens access otherwise inaccessible nutrients, offering potential strategies for developing disease-resistant citrus varieties.

    Trang Thi-Thu Phan et al, Xanthomonas coordinates type III–type II effector synergy by activating fruit-ripening pathway, Science (2025). DOI: 10.1126/science.adz9239

  • Dr. Krishna Kumari Challa

    Is aging an act of genetic sabotage? Scientists find a gene that turns off food detection after reproduction

    A gene called nhr-76 in roundworms actively suppresses food-odor detection after reproduction by switching off related sensory genes in neurons. This programmed decline, rather than accumulated damage, suggests aging can involve active genetic regulation. Similar genes in mammals may play related roles, but their effects in humans remain unconfirmed.

    Rikuou Yokosawa et al, A Nuclear Hormone Receptor nhr‐76 Induces Age‐Dependent Chemotaxis Decline in C. elegans, Aging Cell (2025). DOI: 10.1111/acel.70277

  • Dr. Krishna Kumari Challa

    Global food systems driving twin crises of obesity and global warming, says review
    Unsustainable, profit-driven food systems promote high-calorie, low-fiber diets, contributing to rising obesity and significant greenhouse gas emissions. Animal-based and ultra-processed foods are key drivers of both health and environmental harms. System-level reforms—such as taxes, subsidies, and marketing restrictions—are recommended to improve diets and reduce climate impact.

    A major review in Frontiers in Science highlights how tackling unsustainable food systems—reflected by our changing food environment—is urgent for both health and climate.

    The paper reviews evidence that both obesity and environmental harms result from a profit-led food system that encourages high intake and poor health. The authors say that our food environment promotes high-calorie, low-fiber products such as some ultra-processed foods (UPFs)—the most caloric of which encourage weight gain.

    Those same production systems, especially involving animals, release large amounts of greenhouse gases and put pressure on land and water.

    The comprehensive review says that addressing the food environment can therefore deliver double benefits for health and climate.

    The authors recommend using subsidies for healthy foods, taxes and warning labels for particularly unhealthy foods, and restrictions on aggressive marketing of high-calorie, low-fiber products, particularly in low-income communities and to children.

    They also counter the perception that weight-loss drugs are a panacea for obesity, as they do not address the systemic drivers which also harm the climate.

    Obesity and climate change: co-crises with common solutions, Frontiers in Science (2025). DOI: 10.3389/fsci.2025.1613595

  • Dr. Krishna Kumari Challa

    Antifungal vaccine heads for clinical trials
    A vaccine designed to protect against infections with certain fungal pathogens is set to move into phase I clinical trials, backed by US$40 million in funding from the US National Institutes of Health. The vaccine, called VXV-01, uses two antigens to elicit an immune response to fungal pathogens such as Candida auris and Candida albicans, which can cause drug-resistant infections in hospitals.

    https://www.genengnews.com/topics/infectious-diseases/fungal-vaccin...

  • Dr. Krishna Kumari Challa

    The Roots of Dementia in Childhood

    Dementia is often associated with older people, but it doesn't just appear out of nowhere.

    Some risk factors could start before we're even born, while others emerge as we progress through childhood into young adulthood.

    According to research, that could be the best time to start intervention.


    Even before we are born, some risk factors for dementia may already be present.

    Increasingly, evidence suggests that the roots of age-related cognitive decline could begin in early childhood.

    One of the most important factors explaining cognitive ability at age 70, researchers say, is cognitive ability at age 11.

    Later, in early adulthood, additional potential risk factors include:

    Education

    Head injuries

    Physical activity

    Social isolation

    Growing up healthy could be key to growing old healthy.

    https://academic.oup.com/psychsocgerontology/article/78/12/2131/728...

    https://www.sciencealert.com/the-roots-of-dementia-trace-back-all-t...
    **
  • Dr. Krishna Kumari Challa

    Quantum computers have memory problems over time

    A team of  international scientists has, for the first time, created a full picture of how errors unfold over time inside a quantum computer—a breakthrough that could help make future quantum machines far more reliable.

    The researchers found that the tiny errors that plague quantum computers don't just appear randomly. Instead, they can linger, evolve and even link together across different moments in time.

    The team has made its experimental data and code openly available, and the full study is published in Quantum.

    This type of behavior is one of the key obstacles to building practical, large-scale quantum computers.

     The team ran a series of experiments on cutting-edge superconducting quantum processors—some in the lab at the University of Queensland and others accessed through IBM's cloud-based quantum computers.

    Previous attempts to map the behaviour of quantum systems over time all hit the same roadblock: after measuring a quantum system mid-experiment, scientists couldn't freely set it up again for the next step, because the setting-up depends on whether the result of the measurement was 0 or 1.

    The new method solves this by adding a clever twist, assuming that 50% of the time, the result was 1, and the remaining time, the result was 0. Then, the researchers used software to work backwards with the data, to figure out what state it was in.

    What they found is that even today's best quantum machines show subtle but important time-linked noise patterns—including noise that is quantum in nature and comes from nearby qubits on the same chip.

    Understanding these patterns will help quantum scientists design better characterization and error-correction tools, a crucial step toward building dependable, fault-tolerant quantum computers.

    Multi-time quantum process tomography on a superconducting qubit, Quantum (2025). DOI: 10.22331/q-2025-12-02-1582

  • Dr. Krishna Kumari Challa

    Ancient viral DNA shapes early embryonic development

    A new study reveals how ancient viral DNA once written off as "junk" plays a crucial role in the earliest moments of life. The research, published in Science Advances, begins to untangle the role of an ancient viral DNA element called MERVL in mouse embryonic development and provides new insights into a human muscle wasting disease.

    Transposable elements are stretches of DNA that can move around the genome. Many of these DNA sequences originate from long ago, when viruses inserted their genetic material into our ancestors' genomes during infection. Today, these viral transposable elements make up around 8-10% of the mammalian genome.

    Once disregarded as "junk" DNA, we now know that many transposable elements play an important role in influencing how genes are turned on and off, especially during early development. They have a variety of beneficial and harmful roles in the body, for example, some help regulate normal immune responses, while others can disrupt genes and contribute to diseases like cancer.

    The latest work focuses on a viral transposable element called MERVL. 

    This element becomes highly active for a short window of time when a mouse embryo reaches the two-cell stage—the point at which a fertilized egg has divided into two cells and switches on its own genome for the first time. Cells in this state are considered "totipotent," meaning they can generate every cell type of the embryo and extraembryonic tissues like the placenta.

    MERVL acts as a central switch to activate a large network of genes specific to the two-cell stage of development.

    To work out the role of MERVL, the team used a gene manipulation technique called CRISPR activation to turn on MERVL elements in mouse embryonic stem cells, to mimic what happens in two-cell embryos.

    In cells where only MERVL was activated, the cells looked like they were only partially similar to cells of the two-cell stage, but they still had several characteristics of totipotency. The researchers described this in-between state as an "intermediate phenotype." They showed that activating MERVL alone is sufficient to create totipotent features in early embryonic development.

    Paul Chammas et al, CRISPRa-mediated disentanglement of the Dux-MERVL axis in the 2C-like state, totipotency and cell death, Science Advances (2025). DOI: 10.1126/sciadv.adu9092www.science.org/doi/10.1126/sciadv.adu9092

  • Dr. Krishna Kumari Challa

    New 'cloaking device' concept shields electronics from disruptive magnetic fields

    Unwanted magnetic fields can disrupt the operation of precision instruments, sensors, and electronic components, leading to signal distortion, data errors, or equipment malfunction. This is a growing concern in environments such as hospitals, power grids, aerospace systems, and scientific laboratories, where increasingly sensitive technologies require effective protection from magnetic interference.

    Researchers have unveiled a concept for a device designed to magnetically "cloak" sensitive components, making them invisible to detection.
    A magnetic cloak is a device that hides or shields an object from external magnetic fields by manipulating how these flow around an object so that they behave as if the object isn't there.

    In Science Advances, the team of engineers demonstrate for the first time that practical cloaks can be engineered using superconductors and soft ferromagnets in forms that can be manufactured.

    Using computational and theoretical techniques such as advanced mathematical modeling and high-performance simulations based on real-world parameters, they have developed a new physics-informed design framework that allows magnetic cloaks to be created for objects of any shape. Until now, cloaks were mostly theoretical or restricted to simple shapes like cylinders.

    This study demonstrates for the first time how to design magnetic cloaks for the irregular geometries we see in the real world. These cloaks also maintain their effectiveness across a broad range of field strengths and frequencies.

    Magnetic cloaks could play a vital role in protecting sensitive electronics and sensors from magnetic interference, which is a growing challenge in everything from medical devices to renewable energy and space technology.

     Yusen Guo et al, Designing Functional Magnetic Cloaks for Real-World Geometries, Science Advances (2025). DOI: 10.1126/sciadv.aea2468www.science.org/doi/10.1126/sciadv.aea2468

  • Dr. Krishna Kumari Challa

    Biophysicists uncover new electrical transmission in cells

    Many biological processes are regulated by electricity—from nerve impulses to heartbeats to the movement of molecules in and out of cells.

    A new study by search scientists reveals a previously unknown potential regulator of this bioelectricity: droplet-like structures called condensates. Condensates are better known for their role in compartmentalizing the cell, but this study shows they can also act as tiny biological batteries that charge the cell membrane from within.

    The team showed that when electrically charged condensates collide with cell membranes, they change the cell membrane's voltage—which influences the amount of electrical charge flowing across the membrane—at the point of contact.

    The discovery, published in the journal Small, highlights a new fundamental feature about how our cells work, and could one day help scientists treat certain diseases.

    Condensates are organelles—structures within cells that carry out specific functions—but unlike more well-known organelles such as the nucleus and mitochondria, they are not enclosed within membranes. Instead, condensates are held together by a combination of molecular and electrical forces. They also occur outside of cells, such as at neuronal synapses.

    Condensates are involved in many essential biological processes, including compartmentalizing cells, protein assembly and signaling both within and between cells. Previous studies have also shown that condensates carry electrical charges on their surfaces, but little is known about how their electrical properties relate to cellular functions.

    If condensates can alter the electrical properties of cell membranes, it could have big implications, because many cellular processes are controlled by changes in the cell membrane voltage. For example, ion channels—proteins that rapidly transport molecules across the cell membrane—are activated by changes in cell membrane voltage.
    In the nervous system, this rapid, one-directional transport of electrically charged molecules is what drives the propagation of electrical signals between nerves.

    Part 1

  • Dr. Krishna Kumari Challa

    To test whether condensates can alter cell membrane voltage, the researchers used cell models called Giant Unilamellar Vesicles (GUVs). To allow them to visualize changes in voltage, they stained GUV membranes with a dye that changes color in response to changes in electrical charge. Then, they put GUVs in the same vessel as lab-made condensates and photographed their interactions under the microscope.

    They showed that when the condensates and GUVs collided, it caused a local change in the GUV membranes' electrical charge at their point of contact.
    By varying the chemical makeup of the condensates, the researchers showed that the more electrical charge a condensate carried, the bigger its impact on cell membrane voltage. They also found that the shape of the condensates appeared to be correlated with variations in the voltage change.

    In some instances, the voltages induced are quite substantial in magnitude—on the same scale as voltage changes in nerve impulses.

    Anthony Gurunian et al, Biomolecular Condensates Can Induce Local Membrane Potentials, Small (2025). DOI: 10.1002/smll.202509591

    Part 2

  • Dr. Krishna Kumari Challa

    Earth's Seasons Are Strangely Out of Sync, Scientists Discover From Space

    Scientists  have watched our planet's seasons from space and discovered that spring, summer, winter, and fall are surprisingly out of sync.

    Just because two places exist in the same hemisphere, at similar altitudes, or at the same latitude doesn't guarantee they'll experience the same seasonal changes at the same time.

    Even regions that are side by side can experience different weather and ecological patterns, sculpting wildly different neighboring habitats.

    It's similar to how time zones can separate two adjacent spots, but in this case, the boundary is drawn by nature itself.

    Using 20 years of satellite data, researchers have created what they say is the most comprehensive map to date of the seasonal timing of Earth's terrestrial ecosystems.

    The new map identifies global regions where seasonal patterns are particularly out of sync, and these asynchronies often occur in biodiversity hotspots.
    That is probably no coincidence. More variability in weather patterns can have trickle-down effects, which may drive greater diversity within habitats.
    For example, if natural resources in two neighboring habitats are made available at different times of the year, it could shape the ecology and evolution of flora and fauna in each spot.

    It could even mean that a species in one habitat reaches its reproductive season before or after the same species in an adjacent habitat, preventing interbreeding.
    Across many generations, this can lead to the evolution of two entirely separate species.

    https://www.nature.com/articles/s41586-025-09410-3

  • Dr. Krishna Kumari Challa

    Holes in your colon!

    Part 1
  • Dr. Krishna Kumari Challa

    Most People Develop Diverticulosis in Their Gut by Age 80

    It's easy to see your body aging on the outside – wrinkles, dark spots, gray hair, the whole shebang – but as we grow older, our insides also inevitably change.
    By the time most people reach the ripe age of 80, the smooth lining of their digestive tract is scattered with small, bulging pouches of tissue.

    These sac-like protrusions along the digestive tract, called diverticula, are 'weak spots' in the gut's muscular wall. They are typically harmless, and most people never even know they are there.
    Sometimes, after a colonoscopy, patients are alarmed to find they have developed diverticulosis, but most of the time, this condition is nothing to worry about.
    Only if the pouches become inflamed or infected is it considered diverticular disease, or diverticulitis. Symptoms, which generally come and go, often include constipation, diarrhea, abdominal pain, bloating, or fever.
    The good news is that even if a person does develop diverticulitis, their symptoms usually improve with just a few days of bed rest and a liquid diet. Over 85 percent of patients find this sufficient.
    No one knows exactly what causes diverticula to form in the first place, but current treatments generally focus on helping the digestive tract move smoothly, without blockages.

    That's why a high-fiber diet, including between 25 and 30 grams of fiber a day, is often recommended to recovering patients. This won't heal existing diverticula, but may prevent more from forming.
    Other potential risk factors include obesity, lack of exercise, and smoking. There's likely a complicated mix of contributing factors.
    Part2
  • Dr. Krishna Kumari Challa

    While diverticula can develop in the large and small intestine, around 95 percent of patients in the Western world have diverticula in their sigmoid colon.

    This part of the digestive tract works under great pressure to push feces into the rectum.

    Once diverticula form, possibly from excessive pressure, they are prone to bleeding when aggravated, in a similar way to hemorrhoids, which form inside and outside the rectum and around the anus.
    Diverticular bleeding is estimated to cause between 30 and 65 percent of all cases of lower gastrointestinal bleeding. It's usually painless and self-limiting, but seeing blood in the stool is a serious matter, as it may indicate other severe conditions.
    Treatment depends on the severity of the episode.

    https://www.sciencealert.com/most-people-develop-diverticulosis-in-...

    Part 3

  • Dr. Krishna Kumari Challa

    2.8 days to disaster: Why we are running out of time in low earth orbit

    Satellite mega-constellations in low Earth orbit experience close approaches every 22 seconds, with each satellite performing frequent avoidance maneuvers. Solar storms increase atmospheric drag and can disable satellite control systems, raising collision risks. If operators lose control, a catastrophic collision could occur within 2.8 days, compared to 121 days in 2018, highlighting increased vulnerability.

    Sarah Thiele et al, An Orbital House of Cards: Frequent Megaconstellation Close Conjunctions, arXiv (2025). DOI: 10.48550/arxiv.2512.09643

  • Dr. Krishna Kumari Challa

    Physicists crack a 'Big Bang Theory' problem that could help explain dark matter
    Theoretical work demonstrates that axions, hypothetical particles considered a candidate for dark matter, could be produced in fusion reactors using deuterium, tritium, and lithium. Neutron interactions with reactor walls and bremsstrahlung processes may generate axions or axion-like particles, offering a new approach to probing dark matter beyond solar-based searches.

    Chaja Baruch et al, Searching for exotic scalars at fusion reactors, Journal of High Energy Physics (2025). DOI: 10.1007/jhep10(2025)215

  • Dr. Krishna Kumari Challa

    The moon-forming event: Why it was by explosive ejection rather than a giant impact
    A new model proposes that the Moon formed from explosive ejection of Earth's mantle and crust, driven by accumulated internal gravitational energy (LɅ) released at the core-mantle boundary, rather than by a giant impact. This mechanism explains the Moon's isotopic similarity to Earth and links geophysical processes, such as mantle plumes and LLVPs, to lunar formation.

    Matthew R. Edwards, Explosive lunar fission above a large low-velocity province, Acta Geochimica (2025). DOI: 10.1007/s11631-025-00834-2

  • Dr. Krishna Kumari Challa

    Scientists observe 'extraordinary' seven-arm octopus
    A rare deep-sea encounter captured footage of the seven-arm octopus, Haliphron atlanticus, at 700 meters depth in Monterey Bay. This species, with females reaching up to 4 m and 75 kg, primarily inhabits the ocean's twilight zone and feeds on gelatinous animals such as jellyfish, supporting previous observations of its unusual diet.

    Hoving, H.J.T. and S.H.D. Haddock. 2017. The giant deep-sea octopus Haliphron atlanticus forages on gelatinous fauna. Scientific Reports, 7: 44952. https://doi.org/10.1038/srep44952

  • Dr. Krishna Kumari Challa

     Natural daylight can help people with diabetes improve blood sugar levels

    People with type 2 diabetes may be able to improve their blood sugar by doing something as simple as sitting by a window for a few hours each day. In a study published in Cell Metabolism, scientists showed that natural daylight helps maintain healthy glucose levels.

    Daylight is known to be a mood enhancer and also beneficial for our health. However, according to the research team, most people living in Western societies typically stay indoors around 80% to 90% of the time under artificial light, which is not as bright or dynamic as sunlight. This is important because the human body operates on circadian rhythms, internal 24-hour clocks that orchestrate a range of biological processes, such as digestion and temperature regulation. These are synchronized by light, and a lack of natural light is a risk factor for type 2 diabetes.

    Previous studies have shown that artificial light at night disrupts these rhythms and that daylight outdoors can improve the body's response to insulin, which helps control blood sugar levels. But no prior research examined how natural light entering a window affects people with diabetes.

    To test this, researchers recruited 13 volunteers with type 2 diabetes to examine how their bodies responded to both natural window lighting and artificial indoor lighting. The participants spent two separate 4.5-day periods in a controlled office environment. In one session, they sat at a desk facing large windows from morning to late afternoon.
    In the other, they were in the same room, with the windows blocked and only standard office lights. All participants ate similar meals three times a day and performed the same exercises at the same time across the two sessions. They also continued taking their medication.

    The results revealed that while average glucose levels were similar across the two sessions, the participants spent significantly more time in the normal glucose range when exposed to natural daylight. The body's metabolism also changed. In daylight, the volunteers burned more fat for energy and fewer carbohydrates.

    The researchers also took muscle biopsies and grew muscle cells in the lab. They found that genes involved in their internal cellular clocks were better aligned to the time of day under natural light. This suggested that sunlight was acting as a signal to keep the muscles "on time," making them better at processing nutrients.

    Although this study involved only a handful of people, the results indicate that natural daylight can help reduce the sharp peaks and swings in blood sugar that often affect those with this condition. It offers a simple, natural way to support people with type 2 diabetes alongside existing treatments.

    Jan-Frieder Harmsen et al, Natural daylight during office hours improves glucose control and whole-body substrate metabolism, Cell Metabolism (2025). DOI: 10.1016/j.cmet.2025.11.006

  • Dr. Krishna Kumari Challa

    Scientists who use AI tools are publishing more papers than ever before

    Science is entering a massive publishing boom, in large part due to artificial intelligence. New research published in the journal Science has revealed that scientists who use large language models (LLMs) like ChatGPT are producing significantly more papers across many fields. The technology is also helping to level the playing field for researchers whose first language isn't English.

    The growing use of AI in scientific research has sparked concerns about shoddy work and machines making things up. But this new analysis also reveals that papers produced with LLMs use more complex language and cite a wider array of sources.

    They found that when scientists use AI, their productivity soared. The biggest jump was in the social sciences and humanities, where output increased by 59.8%, while biology and life sciences saw a 52.9% increase. Meanwhile, in physics and math, the scientists report a 36.2% boost. "LLM adoption is associated with a large increase in researchers' scientific output," wrote the research team in their paper.

    One of the most fascinating findings was the massive increase in productivity from non-English-speaking countries. Most top journals require manuscripts to be written in high-level English, which has long disadvantaged these scientists. But with AI handling some of the workload, researchers from Asia saw their output jump by as much as 89% in some cases.
    However, the study authors also issued a warning regarding AI and quality. While the machines can make papers sound more professional, this can be a trap. Historically, sophisticated writing was a sign of high-quality research, but now the opposite can sometimes be true. The study found that the more complex the AI-generated writing was, the less likely the paper was to be high quality. In other words, good writing can mask weak ideas.

    The clear message from the study authors is that we can no longer judge a paper by how smart the language appears. "As traditional heuristics break down, editors and reviewers may increasingly rely on status markers such as author pedigree and institutional affiliation as signals of quality, ironically counteracting the democratizing effects of LLMs on scientific production."

    To safeguard scientific integrity, the researchers propose several measures, including that institutions implement deeper checks and even specialized "AI-based reviewer agents" to help distinguish between human writing and machine-generated writing.

     Keigo Kusumegi et al, Scientific production in the era of large language models, Science (2025). DOI: 10.1126/science.adw3000

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  • Dr. Krishna Kumari Challa

    How chirality goes from the molecular level to the cellular one

    Researchers have discovered how right-handed molecules in our cells can give rise to cells that are not symmetrical about their central axes. This discovery is a key step toward determining why most of our organs lack left–right symmetry.

    It's conceivable that if some molecules that make up our cells were twisted in the opposite direction, our hearts would be on the right side of our bodies rather than on the left.

    That's because the difference between the left and right sides of our organs may originate from the "handedness," or chirality, of cells, which in turn comes from the chirality of molecules in cells.

    However, the link between the chirality of molecules and cellular chirality is largely unknown. Many molecules in cells are chiral, including DNA and some amino acids and proteins, but it's not clear which ones convey their chirality to cells.

     By studying the chiral behaviours of individual cells, researchers have found that the cells' scaffolding, or cytoskeleton, gives rise to the cell's chirality. The findings are published in the journal eLife.

    When single cells were placed on a substrate, their nuclei and surrounding cytoplasm rotated in a clockwise direction when viewed from above. This rotational motion is driven by the concentric pattern of the actomyosin filaments that make up the cytoskeleton.

    This finding implies that the cell nucleus can rotate even when there is no chiral orientation of the cytoskeleton on a cellular level.
    To confirm whether this mechanism was driving the rotation, the team created a 3D theoretical model of a cell and evaluated the effect of the molecular chirality of actin and myosin on it. The results revealed that the molecular scale torque generated by individual components of the cytoskeleton can generate rotation, even when cell-level chiral structures were absent.

    These results help fill in a critical link in the chain from molecules to organs and bodies, the researchers say.

     Takaki Yamamoto et al, Epithelial cell chirality emerges through the dynamic concentric pattern of actomyosin cytoskeleton, eLife (2025). DOI: 10.7554/elife.102296

  • Dr. Krishna Kumari Challa

    PFAS concentrations can double with every step up the food chain
    PFAS concentrations increase twofold on average with each step up the food chain, resulting in significantly higher levels in top predators and humans. Analysis of 119 global food webs shows substantial variation among PFAS compounds, with some newer alternatives magnifying even more than legacy chemicals. These findings highlight the need for compound-specific regulation and further research into health impacts.

    The authors examined 119 aquatic and terrestrial food webs across the globe, finding that top predators such as large fish, seabirds, and marine mammals can accumulate PFAS concentrations exponentially larger than the environments in which they're found. The study is published in the journal Nature Communications.

    PFAS concentrations double, on average, with each step up the food chain.

    Known as "forever chemicals," PFAS are from a family of more than 12,000 man-made compounds.
    These chemicals are prized for their heat resistance and water-repelling properties, and are used in cleaning products, food packaging, non-stick pans, clothing, and fire-fighting equipment.

    Since being discovered by the American chemical company DuPont in the 1930s, PFAS are now detectable in the bloodstream of almost every human being on the planet.

    Unlike other chemicals, PFAS never break down, meaning that throughout the world right now, they're building up in environments, plants, and animals on land and in the ocean.

    For humans, sitting as we do at the top of the food chain, this means our diets can be an important pathway for PFAS exposure.

    Given what we know about PFAS toxicity from other studies, these extreme accumulation rates in top predators suggest serious health risks. This creates a cascading ecological risk: Apex predators face disproportionately high exposure even in relatively low-contaminated environments.

    Some compounds—including chemicals marketed as safer alternatives to existing products—showed even higher magnification than the chemicals they were designed to replace.

     Lorenzo Ricolfi et al, Unravelling the magnitude and drivers of PFAS trophic magnification: a meta-analysis, Nature Communications (2025). DOI: 10.1038/s41467-025-65746-4

  • Dr. Krishna Kumari Challa

    More eyes on the skies can help planes reduce climate-warming contrails

    Aviation's climate impact is partly due to contrails—condensation that a plane streaks across the sky when it flies through icy and humid layers of the atmosphere. Contrails trap heat that radiates from the planet's surface, and while the magnitude of this impact is uncertain, several studies suggest contrails may be responsible for about half of aviation's climate impact.
    Geostationary satellites detect only about 20% of contrails visible to low-Earth-orbiting satellites, primarily missing smaller, younger contrails. Combining data from geostationary, low-Earth-orbit, and ground-based observations can provide a more complete understanding of contrail formation and evolution, supporting more effective contrail avoidance strategies to mitigate aviation's climate impact.

    Pilots could conceivably reduce their planes' climate impact by avoiding contrail-prone regions, similarly to making altitude adjustments to avoid turbulence. But to do so requires knowing where in the sky contrails are likely to form.

    To make these predictions, scientists are studying images of contrails that have formed in the past. Images taken by geostationary satellites are one of the main tools scientists use to develop contrail identification and avoidance systems.

    But a new study shows there are limits to what geostationary satellites can see.

    Researchers analyzed contrail images taken with geostationary satellites, and compared them with images of the same areas taken by low-Earth-orbiting (LEO) satellites. LEO satellites orbit Earth at lower altitudes and therefore can capture more detail. However, since LEO satellites only snap an image as they fly by, they capture images of the same area far less frequently than geostationary (GEO) satellites, which continuously image the same region of Earth every few minutes.

    The researchers found that geostationary satellites miss about 80% of the contrails that appear in LEO imagery. Geostationary satellites mainly see larger contrails that have had time to grow and spread across the atmosphere. The many more contrails that LEO satellites can pick up are often shorter and thinner. These finer threads likely formed immediately from a plane's engines and are still too small or otherwise not distinct enough for geostationary satellites to discern. The study highlights the need for a multiobservational approach in developing contrail identification and avoidance systems. The researchers emphasize that both GEO and LEO satellite images have their strengths and limitations.

    Observations from both sources, as well as images taken from the ground, could provide a more complete picture of contrails and how they evolve.

    With more 'eyes' on the sky, we could start to see what a contrail's life looks like, the researchers conclude.

     Marlene V. Euchenhofer et al, Contrail Observation Limitations Using Geostationary Satellites, Geophysical Research Letters (2025). DOI: 10.1029/2025gl118386

  • Dr. Krishna Kumari Challa

    Biodegradable electronics can break down into harmful microplastics
    Some materials used in biodegradable electronics, such as PEDOT:PSS, can persist for years and degrade into microplastics, raising environmental concerns. In contrast, polymers like cellulose and silk fibroin degrade more safely. The environmental impact of both material choice and manufacturing processes is significant, highlighting the need for sustainable, circular approaches in electronics production.

    Sofia Sandhu et al, End-of-Life usefulness of degradation by products from transient electronics, npj Flexible Electronics (2025). DOI: 10.1038/s41528-025-00411-w

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  • Dr. Krishna Kumari Challa

    People are getting their news from AI—and it's altering their views

    Large language models increasingly shape public opinion by generating news content and summaries, often introducing subtle communication bias by emphasizing certain viewpoints while minimizing others, even when information is accurate. This bias stems from model design, training data, and market concentration. Current regulations focus on harmful outputs but are less effective against nuanced framing biases, highlighting the need for greater competition, transparency, and user involvement.

     Read the original article.

  • Dr. Krishna Kumari Challa

    Scientists chart over 140,000 DNA loops to map human chromosomes in the nucleus
    Over 140,000 DNA looping interactions were mapped in human embryonic stem cells and fibroblasts, providing a detailed 3D organization of chromosomes within the nucleus. Computational models now predict genome folding from DNA sequence alone, clarifying how chromatin loops influence gene regulation and how genetic variations may alter genome structure and function.

    Job Dekker et al, An integrated view of the structure and function of the human 4D nucleome, Nature (2025). DOI: 10.1038/s41586-025-09890-3

    Elzo de Wit, Systematic maps reveal how human chromosomes are organized, Nature (2025). DOI: 10.1038/d41586-025-03808-9

  • Dr. Krishna Kumari Challa

    Two ancient human species came out of Africa together, not one, suggests new study

    The textbook version of the "Out of Africa" hypothesis holds that the first human species to leave the continent around 1.8 million years ago was Homo erectus. But in recent years, a debate has emerged suggesting it wasn't a single species, but several. New research published in the journal PLOS One now hopes to settle the matter once and for all.

    The debate centers on the Dmanisi fossils, five skulls found in the Republic of Georgia between 1999 and 2005, which belong to some of the oldest humans ever found outside Africa. The problem is that they don't look alike. Some are larger than others, particularly Skull 5, which has a tiny braincase but a massive, protruding face. Some researchers explain this as a difference in sexes within the same species, while others argue that it represents two distinct species living together.

    To provide much-needed clarity, researchers studied the teeth of three Dmanisi specimens. The reason is that, generally, skulls are not always the best species identifiers because bone is fragile and can be warped and crushed. Dentition is far more useful because enamel is the hardest biological substance produced by humans, and everything from the shape and size of individual teeth can be used to identify a species.

    The team focused on the surface area (dental crown) of the back teeth (premolars and molars) of the Dmanisi specimens that had sufficient dental remains for analysis. They compared these to a database of 122 other fossil specimens, including Australopithecus and several other Homo species. Then, using a statistical sorting tool, they analyzed 583 teeth to create a biological map and determine whether the Dmanisi fossils belonged to a single family or to other branches of our family tree.

    The map revealed that these ancient remains were not from a single group. Skull 5, with its large jaw, was grouped with Australopiths, a more primitive ape-like ancestor. The other two specimens were more human-like. Because of this, the study authors support using the names Homo georgicus for Skull 5 and Homo caucasi for the human-like group.
    To ensure the differences weren't just between males and females, the team compared the fossils with those of great apes. In some animals, like gorillas, males are much larger than females but still have the same basic teeth. The differences between the Dmanisi teeth were so great that male-female differences within the same group couldn't explain them.
    Part 1
  • Dr. Krishna Kumari Challa

    The postcanine dental crown area analysis of the Dmanisi hominin fossils... supports the hypothesis of distinct species coexisting temporally at the site (Homo caucasi and Homo georgicus). This possibility challenges the prevailing model of Homo erectus migration out of Africa..." commented the researchers in their paper.

    While the research lends weight to the idea that two species left Africa at roughly the same time, more specimens may be needed before a consensus is reached.

    Victor Nery et al, Testing the taxonomy of Dmanisi hominin fossils through dental crown area, PLOS One (2025). DOI: 10.1371/journal.pone.0336484

    Part 2

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  • Dr. Krishna Kumari Challa

    Some mammals can hit pause on a pregnancy—understanding how that happens could help us treat cancer
    Embryonic diapause allows some mammals to pause development by activating a molecular brake that suppresses differentiation pathways, maintaining stem cell pluripotency during metabolic stress. This mechanism involves the displacement of Capicua, enabling genes that inhibit the MAP kinase pathway. The findings suggest similar dormancy programs may underlie long-term survival in immune, stem, and cancer cells.

    Tuo Zhang et al, Transcriptional derepression of negative regulators of MAP kinase supports maintenance of diapause ES cells in the pluripotent state, Genes & Development (2025). DOI: 10.1101/gad.353143.125

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  • Dr. Krishna Kumari Challa

  • Dr. Krishna Kumari Challa

    Whale, dolphin strandings show widespread disease, trauma
    Analysis of 272 cetacean strandings in the Pacific Islands from 2006 to 2024 found that over 65% involved disease or human-caused trauma. Disease accounted for 62% of cases, with infectious agents like morbillivirus and brucella affecting multiple species. Human-related trauma, including vessel strikes and debris ingestion, contributed to 29% of strandings.

    From land-borne pathogens to high-speed vessel strikes, Pacific whales and dolphins are caught in a "perfect storm" where human-caused trauma and infectious diseases were found in more than 65% of investigated strandings.

    A study spanning nearly two decades by  researchers provides insights into the threats whales and dolphins face in the Pacific Islands.

    Based on 272 stranding investigations of 20 cetacean species between 2006 and 2024, the study provides foundational data to better manage and conserve Hawaiʻi's whales and dolphins. The findings are published in the journal Diseases of Aquatic Organisms.

    Over 18 years, scientists examined more than three-quarters of the stranded whales and dolphins to understand why they died. Most cases (62%) were linked to diseases, and about half of those animals were in poor body condition due to long-term illness.
    Infectious agents proved to be a significant threat, affecting 11 different species, including striped dolphins and Longman's beaked whales. Two of the most concerning pathogens were morbillivirus and brucella, which can cause serious brain and lung problems in marine mammals.

    Toxoplasmosis—a parasite that infects warm-blooded animals and spreads through cat feces across the environment—was responsible for the deaths of two spinner dolphins and one bottlenose dolphin.

    The study revealed that 29% of all strandings were linked to anthropogenic (human-caused) trauma. Vessel strikes were a significant risk, resulting in fatal vertebral and skull fractures for seven individuals, including two pygmy sperm whales, two humpback whale calves, a goose-beaked whale, a spinner dolphin and a striped dolphin.

    Interactions with marine debris and fisheries were confirmed as fatal in multiple cases, including a sperm whale that died from plastic and fishery debris blocking its stomach and a bottlenose dolphin that died after a fishhook tore into it.

    Kristi West et al, Pacific Islands cetaceans: a review of strandings from 2006-2024, Diseases of Aquatic Organisms (2025). DOI: 10.3354/dao03877

  • Dr. Krishna Kumari Challa

    Gut bacteria may play role in bipolar depression by directly influencing brain connectivity

    Bipolar disorder (BD) is a psychiatric disorder characterized by extreme mood changes. Individuals diagnosed with BD typically alternate between periods of high energy, euphoria, irritability and/or impulsivity (i.e., manic episodes) and others marked by feelings of sadness, low energy, and hopelessness (i.e., depression).

    While there are now several medications that can help patients to manage the disorder and stabilize their mood, many of these drugs have side effects and dosages often need to be periodically adjusted. Recent studies suggest that the bacteria and microorganisms living in the digestive system, also known as gut microbiota, play a key role in mental health and might also contribute to some symptoms of BD.

    Researchers  recently carried out a study investigating the possible connection between gut microbiota and the depressive episodes experienced by people diagnosed with BD. Their findings, published in Molecular Psychiatry, suggest that the microorganisms in the digestive system can directly influence connections between specific brain regions known to be affected by BD depression.

    Adequate evidence has shown that gut microbial dysbiosis is an emerging disease phenotype of BD and is closely related to clinical symptoms of this intractable disease, wrote the researchers in their paper.

    To explore the link between gut microbiota and BD depression, the researchers collected gut bacteria from individuals diagnosed with BD who were going through a depressive phase. They then transplanted these bacteria into the digestive system of healthy mice.

    They found that bipolar depression-like mice presented with a decrease in the density of dendrite spines in medial prefrontal neurons, and translation post-synapse as a key contributor to the changes in synaptic plasticity.

    In addition, analysis of synaptic connectivity in the mPFC revealed that compared to control mice, fewer connections were observed between ventral tegmental area and mPFC glutamate neurons and dopamine response was decreased in BD mice.

    Notably, the researchers found that after they received the microbiota taken from individuals who were experiencing BD depression, the mice also started exhibiting depression-like behaviors. In addition, neurons in two brain regions known to be implicated in mood regulation, namely the ventral tegmental area (VTA) and the medial prefrontal cortex (mPFC), appeared to be less connected with each other.

    The team also observed disruptions in the production of proteins and reduced dopamine signaling. Dopamine signaling (i.e., the release of dopamine) is essential for maintaining motivation and emotional regulation.

    The results of this study confirm that microorganisms and bacteria in the gut can influence the connections between neurons in different brain regions. These altered connections could in turn have an impact on motivation, mood regulation and the processing of emotions.

    Part1

  • Dr. Krishna Kumari Challa

    The team's findings will need to be validated in humans before they can be reliably translated into psychiatric and medical insight. In the future, however, they could potentially help to identify promising pathways for the treatment of depression in patients diagnosed with BD, which are designed to alter their gut microbiota.

    Anying Tang et al, Gut microbiota modulates synaptic plasticity, connectivity, and dopamine transmission in the VTA-mPFC pathway in bipolar depression, Molecular Psychiatry (2025). DOI: 10.1038/s41380-025-03398-y.

    Part 2

  • Dr. Krishna Kumari Challa

    Brain chemistry can reactivate or suppress dormant HIV

    Human immunodeficiency virus (HIV) infections are still fairly common and an estimated 40 million people worldwide are currently living with this condition. The HIV virus attacks the body's immune system and thus makes those who contract it more vulnerable to a wide range of infections.

    While there is still no known cure for HIV, there are now various treatment options that allow affected patients to live long and healthy lives. When treated with antiretroviral therapy (ART), the virus is known to remain in a latent state, essentially 'hiding' inside cells and forming a reservoir of dormant virus. If the medication is stopped, however, the virus can be re-awoken, causing severe immune deficiencies again.

    Researchers have recently been investigating how the brain, particularly tiny molecules and protein-carrying packages released by cells, influence the persistence of HIV. In a new paper, published in Molecular Psychiatry, they presented new findings that shed new light on molecular mechanisms that can either re-ignite or suppress latent HIV.

    In their experiments the researchers found that ECs collected from the brains of SIV-infected but untreated macaques strongly re-activated latent virus reservoirs increasing the activity of viral genes, the production of proteins and causing the virus to spread between cells. Interestingly, however, particles extracted from the brains of infected macaques who were treated with cannabinoids were found to suppress the re-activation of the virus.

    "Cannabinoids have been shown to inhibit neuroinflammation," said the authors of the research paper. They showed that cannabinoids exert similar anti-inflammatory effects via EVs and in the current study on ECs, we report that ECs isolated from brains (basal ganglia) of rhesus monkeys have this anti-inflammatory effect and that cannabinoids modulate the cargos of the ECs, with resultant effects on latent HIV reservoirs.

    Overall, the findings gathered by these researchers suggest that the brain's chemistry, particularly ECs, do play a key role in the reactivation or suppression of dormant HIV. In the future, their work could pave the way for the development of new drugs and therapeutic interventions aimed at better managing, or perhaps even curing, HIV infections.

    Wasifa Naushad et al, Extracellular condensates (ECs) are endogenous modulators of HIV transcription and latency reactivation, Molecular Psychiatry (2025). DOI: 10.1038/s41380-025-03354-w.

  • Dr. Krishna Kumari Challa

    The global fish trade is spreading 'forever chemicals' around the world

    Eating fish may well be good for you, but it carries a hidden risk of exposure to so-called "forever chemicals." A new study published in the journal Science has revealed that the global seafood trade is acting as a massive delivery system for per- and polyfluoroalkyl substances (PFAS), industrial pollutants that persist in the environment for decades.

    These forever chemicals are used in many products, from nonstick cookware and cosmetics to food packaging and firefighting foams. They are extremely resistant to breaking down in the environment and have been linked to a variety of serious illnesses such as cancer and liver disease.

    PFAS can travel long distances around the planet in the air and through water. Once they wash into the ocean, they are absorbed by tiny organisms at the bottom of the food chain, such as plankton and algae. Because these chemicals do not break down, they accumulate in their bodies, and when small fish eat them, the toxic substances pass up the food chain. Large predatory fish, the kind that end up on our dinner plates, eat these smaller marine creatures, and as a result, the chemical concentrations build up in their tissues and organs.

    In their paper, the researchers set out to map how these chemicals move once they are inside the fish. They built a computer model covering 212 different species to track how toxins accumulate up the food chain and then validated this with lab tests on fish from numerous countries. Then the team combined this data with global trade records to see how the fish and PFAS travel from one country to another.

    One of the most significant findings was that the international fish trade acts like a global conveyor belt, redistributing PFAS from contaminated regions to consumers thousands of miles away.
    Before this study, it was generally assumed that forever chemicals were a local problem. If your country's rivers and seas were clean, then so were the fish. However, a nation with clean water can still be exposed to high levels of PFAS through the seafood it imports from other parts of the world. For example, researchers found that Italians buy only 11% of their fish from Sweden, yet this accounts for more than 35% of their PFAS exposure.

    Given that this problem doesn't respect borders, researchers argue that a unified global strategy is needed to protect public health.

    Wenhui Qiu et al, Risks of per- and polyfluoroalkyl substance exposure through marine fish consumption, Science (2025). DOI: 10.1126/science.adr0351

    Jennifer Sun et al, Reevaluating PFAS exposure risks from marine fish, Science (2025). DOI: 10.1126/science.aed7431

  • Dr. Krishna Kumari Challa

    Raindrops form 'sandballs' as they roll downhill, contributing more to erosion than previously thought

    We know that the initial splash of raindrops on soil contributes to erosion, but a new study, published in the Proceedings of the National Academy of Sciences, finds that the journey of the raindrop downhill might have an even bigger impact on erosion than the initial splash.

    Researchers observed natural raindrops hitting the surface of a hillside and noticed that they collected particles of sand as they rolled downhill. This spurred the researchers to document the event with a camera and then take the idea to the lab.

    In the lab, they constructed a 1.2 meter long bed covered with dry silicate sand and tilted at an angle of 30°. The lab conditions enabled the team to properly document the phenomenon by recording the evolution of the raindrops' shapes as they rolled and take precise measurements of the relevant parameters. They found that each raindrop formed what they refer to as "sandballs" and that they took on differing shapes, depending on the conditions, and that the sandballs can move up to 10 times more soil than the initial splash alone.

    "In the initial rolling stage, drops rapidly increase their speed and sediment entrainment rate. Under increasing centrifugal force, the rolling drops undergo a metamorphosis: Their rounded shape destabilizes, as both liquid and entrained grains drift away from the core to create sandballs," the study authors write in their paper.

    The researchers found that the sandy raindrops formed two distinct shapes: a peanut shape and a doughnut shape. Peanuts occurred at comparably lower velocities and maintained their grains at the surface of the drop. They only gather grains up to a certain point and then usually plateau.

    "Once their mass plateaus, peanuts continue to increase their angular velocity as they roll; this sometimes causes a shift in their mode of motion, triggering an additional phase of mass accumulation. Other times, peanuts break, tumble slower or settle. If peanuts survive to the end of the slope and roll onto a flat surface, they immediately fall apart," the study authors explain.

    Instead of only gathering grains at the surface, doughnut-shaped drops absorb sand grains into their interior volume, making them more dense and opaque in appearance. The researchers call the emergence of these kinds of drops "unexpected."

    The team found that these drops destabilize into the doughnut shape from axisymmetric radial stretching. These shapes only occur at very high spin rates in pure-liquid drops, but occurred at slightly lower rates in the lab experiments due to the water-glycerol mixture used in the lab-based drops.

    Part 1