Science Simplified!

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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

    Nuclear clock paves way for ultraprecise timekeeping

    A new type of clock under development—a nuclear clock—could revolutionize how we measure time and probe fundamental physics.

    An international research team led by scientists at JILA, a joint institute of the National Institute of Standards and Technology (NIST) and the University of Colorado Boulder, has demonstrated key elements of a nuclear clock. A nuclear clock is a novel type of timekeeping device that uses signals from the core, or nucleus, of an atom.

    The team presents the results in the Sept. 4 issue of the journal Nature as a cover story.

    The team used a specially designed ultraviolet laser to precisely measure the frequency of an energy jump in thorium nuclei embedded in a solid crystal. They also employed an optical frequency comb, which acts like an extremely accurate light ruler, to count the number of ultraviolet wave cycles that create this energy jump. While this laboratory demonstration is not a fully developed nuclear clock, it contains all the core technology for one.
    Nuclear clocks could be much more accurate than current atomic clocks, which provide official international time and play major roles in technologies such as GPS, internet synchronization, and financial transactions.

    For the general public, this development could ultimately mean even more precise navigation systems (with or without GPS), faster internet speeds, more reliable network connections, and more secure digital communications.

    Beyond everyday technology, nuclear clocks could improve tests of fundamental theories for how the universe works, potentially leading to new discoveries in physics. They could help detect dark matter or verify if the constants of nature are truly constant, allowing for verification of theories in particle physics without the need for large-scale particle accelerator facilities.

    Chuankun Zhang, Frequency ratio of the 229mTh isomeric transition and the 87Sr atomic clock, Nature (2024). DOI: 10.1038/s41586-024-07839-6www.nature.com/articles/s41586-024-07839-6

  • Dr. Krishna Kumari Challa

    People facing life-or-death choice put too much trust in AI

    In simulated life-or-death decisions, about two-thirds of people in a  study allowed a robot to change their minds when it disagreed with them—an alarming display of excessive trust in artificial intelligence, researchers said.

    Human subjects allowed robots to sway their judgment, despite being told the AI machines had limited capabilities and were giving advice that could be wrong. In reality, the advice was random.

    As a society, with AI accelerating so quickly, we need to be concerned about the potential for over trust, say the researchers.

    What we need instead is a consistent application of doubt.

    We should have a healthy skepticism about AI, the researchers say, "especially in life-or-death decisions."

     Colin Holbrook et al, Overtrust in AI Recommendations About Whether or Not to Kill: Evidence from Two Human-Robot Interaction Studies, Scientific Reports (2024). DOI: 10.1038/s41598-024-69771-z

  • Dr. Krishna Kumari Challa

    Fungal spores of the mold Aspergillus fumigatus produce an enzyme that weakens the immune system

    Aspergillus fumigatus is a mold that is found all over the world. Unlike closely related species, it can cause serious, often fatal infections in humans. What makes A. fumigatus so dangerous?

    A special enzyme on the surface of the fungal spores—glycosylasparaginase—apparently suppresses the release of pro-inflammatory substances by immune cells, making it easier for the pathogen to spread unhindered in the tissue. The findings are published in the journal Nature Microbiology.

    Camila Figueiredo Pinzan et al, Aspergillus fumigatus conidial surface-associated proteome reveals factors for fungal evasion and host immunity modulation, Nature Microbiology (2024). DOI: 10.1038/s41564-024-01782-y

  • Dr. Krishna Kumari Challa

    Arctic microalgae show photosynthesis in near darkness is possible

    Photosynthesis converts sunlight into biologically usable energy and thus forms the basis of all life on our planet. However, previous measurements of the amount of light required for this have always been well above the theoretically possible minimum. The study shows that the build-up of biomass can actually take place with a quantity of light that is close to this minimum.

    Photosynthesis can take place in nature even at extremely low light levels. This is the result of an international study that investigated the development of Arctic microalgae at the end of the polar night. The measurements were carried out as part of the MOSAiC expedition at 88° northern latitude and revealed that even this far north, microalgae can build up biomass through photosynthesis as early as the end of March.

    At this time, the sun is barely above the horizon, so that it is still almost completely dark in the microalgae's habitat under the snow and ice cover of the Arctic Ocean. The results of the study now published in the journal Nature Communications show that photosynthesis in the ocean is possible under much lower light conditions, and can therefore take place at much greater depths than previously assumed.

    Clara J.M. Hoppe, Photosynthetic light requirement near the theoretical minimum detected in Arctic microalgae, Nature Communications (2024). DOI: 10.1038/s41467-024-51636-8

  • Dr. Krishna Kumari Challa

    Newly discovered viruses in parasitic nematodes could change our understanding of how they cause disease

    New research shows that parasitic nematodes, responsible for infecting more than a billion people globally, carry viruses that may solve the puzzle of why some cause serious diseases.

    A study led by Liverpool School of Tropical Medicine (LSTM) used cutting-edge bioinformatic data mining techniques to identify 91 RNA viruses in 28 species of parasitic nematodes, representing 70% of those that infect people and animals. Often these are symptomless or not serious, but some can lead to severe, life-changing disease.

    Nematode worms are the most abundant animals on the planet, prevalent in all continents worldwide, with several species infecting humans as well as agriculturally and economically important animals and crops. And yet in several cases, scientists do not know how some nematodes cause certain diseases.

    The new research, published in Nature Microbiology, opens the door to further study of whether these newly discovered viruses—only five of which were previously known to science—could contribute to many chronic, debilitating conditions. If a connection can be proven, it could pave the way for more effective treatments in the future.

    This raises the question of whether any of the diseases that these parasites are responsible for could be driven by the virus rather than directly by the parasitic nematode.

    Parasitic nematodes including hookworms and whipworms can cause severe abdominal problems and bloody diarrhea, stunted development and anemia. Infection with filarial worms can lead to disfiguring conditions such as lymphedema or "elephantiasis," and onchocerciasis, or "river blindness," that leads to blindness and skin disease.

    The study authors propose that these newly identified viruses may play a role in some of these conditions. For example, onchocerciasis-associated epilepsy (OAE) that occurs in children and adolescents in Sub-Saharan Africa has recently been associated with onchocerciasis, but it is not known why this causes neurological symptoms such as uncontrollable repeated head nodding, as well as severe stunting, delayed puberty and impaired mental health.

    One of the viruses in the parasites that cause onchocerciasis identified in the new study is rhabdovirus—the type that causes rabies. The authors of the study suggest that if this virus is infecting or damaging human nerve or brain tissue, that could explain the symptoms of OAE.

    The full extent and diversity of the viruses living in parasitic nematodes, how they impact nematode biology and whether they act as drivers of disease in people and animals now requires further study.

    Quek, S., et al. Diverse RNA viruses of parasitic nematodes can elicit antibody responses in vertebrate hosts, Nature Microbiology (2024). DOI: 10.1038/s41564-024-01796-6www.nature.com/articles/s41564-024-01796-6

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  • Dr. Krishna Kumari Challa

    Older women more vulnerable to heat than their male peers, researchers find

    As global climate change causes extreme heat waves to become more common around the world, epidemiological studies have shown that heat kills more women than men.

    Now, a new study by researchers at Penn State has found that older women are physiologically more vulnerable to high heat and humidity than older men, and that women between the ages of 40 and 64 are as vulnerable as men 65 years of age or older.

    This is the first study to determine that this disparity exists due to physiological differences and not because women live longer than men, which leaves a larger population of older women than older men.

     the researchers demonstrated that middle-aged and older women were affected by heat at lower temperature/humidity combinations than middle-aged and older men.

    The results, published in the American Journal of Physiology: Regulatory, Integrative and Comparative Physiology, were somewhat unexpected because there are no differences in heat vulnerability based on biological sex in adults younger than 30.

    In addition to demonstrating that middle-aged and older women are at greater risk from extreme heat, we also identified what levels of heat and humidity are safe for women as they age. This information is presented as a temperature/humidity curve based on a person's age, and it can be useful for setting policies designed to keep people safe during a heat wave.

     Olivia K. Leach et al, Sex differences in heat stress vulnerability among middle-aged and older adults (PSU HEAT Project), American Journal of Physiology: Regulatory, Integrative and Comparative Physiology (2024). DOI: 10.1152/ajpregu.00114.2024

  • Dr. Krishna Kumari Challa

    Insulin and metformin combo aids diabetic foot ulcer healing, new study finds

    People with chronic diabetic foot ulcers could soon have a new way to treat their wounds for faster healing and fewer hospital stays. Researchers from Michigan State University and South Shore Hospital have uncovered that the combination of two common diabetes drugs—injectable insulin and orally-administered metformin—increases the amount of metformin at the wound site. As metformin can accelerate wound healing, this could be welcome news for the 18.6 million people worldwide who develop a diabetic foot ulcer, or DFU, in their lifetimes.

    Until now, pharmacological studies had not found an interaction between insulin and metformin. This new study shows that there could be at least an indirect role of consuming both insulin and metformin in a way that metformin can end up in a wound area where it enhances the body's capacity to heal.

     Lisa Gould et al, Analysis of Biogenic Amines and Small Molecule Metabolites in Human Diabetic Wound Ulcer Exudate, ACS Pharmacology & Translational Science (2024). DOI: 10.1021/acsptsci.4c00418

  • Dr. Krishna Kumari Challa

    Researchers Find Signs Of Dementia In How People Speak

    Individuals with memory-related mild cognitive impairment talked less and used fewer but more general nouns.

    https://alz-journals.onlinelibrary.wiley.com/doi/10.1002/dad2.12588

  • Dr. Krishna Kumari Challa

    Will humans accept robots that can lie? Scientists find it depends on the lie

    Honesty is the best policy… most of the time. Social norms help humans understand when we need to tell the truth and when we shouldn't, to spare someone's feelings or avoid harm. But how do these norms apply to robots, which are increasingly working with humans? To understand whether humans can accept robots telling lies, scientists asked almost 500 participants to rate and justify different types of robot deception.

    The scientists selected three scenarios reflecting situations where robots already work—medical, cleaning, and retail work—and three different deception behaviors. These were external state deceptions, which lie about the world beyond the robot, hidden state deceptions, where a robot's design hides its capabilities, and superficial state deceptions, where a robot's design overstates its capabilities.

    In the external state deception scenario, a robot working as a caretaker for a woman with Alzheimer's lies that her late husband will be home soon. In the hidden state deception scenario, a woman visits a house where a robot housekeeper is cleaning, unaware that the robot is also filming. Finally, in the superficial state deception scenario, a robot working in a shop as part of a study on human–robot relations untruthfully complains of feeling pain while moving furniture, causing a human to ask someone else to take the robot's place. Hmmm!

    The scientists recruited 498 participants and asked them to read one of the scenarios and then answer a questionnaire. This asked participants whether they approved of the robot's behavior, how deceptive it was, if it could be justified, and if anyone else was responsible for the deception. These responses were coded by the researchers to identify common themes and analyzed.

    The participants disapproved most of the hidden state deception, the housecleaning robot with the undisclosed camera, which they considered the most deceptive. While they considered the external state deception and the superficial state deception to be moderately deceptive, they disapproved more of superficial state deception, where a robot pretended it felt pain. This may have been perceived as manipulative.

    Participants approved most of the external state deception, where the robot lied to a patient. They justified the robot's behavior by saying that it protected the patient from unnecessary pain—prioritizing the norm of sparing someone's feelings over honesty.

    Andres Rosero et al, Exploratory Analysis of Human Perceptions of Social Robot Deception Behaviors, Frontiers in Robotics and AI (2024). DOI: 10.3389/frobt.2024.1409712www.frontiersin.org/journals/r … 9/frobt.2024.1409712

  • Dr. Krishna Kumari Challa

    Human brain cancers fire electrical impulses: Researchers reveal unexpected hybrid cell spiking the signals

    Researchers  have uncovered a new cell type in the human brain.

    The study published in Cancer Cell reveals that a third of the cells in glioma, a type of brain tumor, fire electrical impulses. Interestingly, the impulses, also called action potentials, originate from tumor cells that are part neuron and part glia, supporting the groundbreaking idea that neurons are not the only cells that can generate electric signals in the brain.

    The scientists also discovered that cells with hybrid neuron-glia characteristics are present in the non-tumor human brain. The findings highlight the importance of further studying the role of these newly identified cells in both glioma and normal brain function.   

    Gliomas are the most common tumors of the central nervous system with an estimated 12,000 cases diagnosed each year. These tumors are universally lethal and have devastating effects on neurological and cognitive functions. Previous studies have shown that patient survival outcomes are associated with tumor proliferation and invasiveness, which are influenced by tumor intrinsic and extrinsic factors, including communication between tumor cells and neurons that reside in the brain.

    Researchers have previously described that glioma and surrounding healthy neurons connect with each other and that neurons communicate with tumors in ways that drive tumor growth and invasiveness.

    Scientists have known for some time now that tumor cells and neurons interact directly.

    To study the ability of glioma cells to spike electrical signals and identify the cells that produce the signals, the team used Patch-sequencing, a combination of techniques that integrates whole-cell electrophysiological recordings to measure spiking signals with single-cell RNA-sequencing and analysis of the cellular structure to identify the type of cells.

    The electrophysiology experiments were conducted by the researchers. 

    This innovative approach has not been used before to study human brain tumor cells.

    The researchers were truly surprised to find these tumor cells had a unique combination of morphological and electrophysiological properties. They had never seen anything like this in the mammalian brain before.

    Finding that so many glioma cells are electrically active was a surprise because it goes against a strongly held concept in neuroscience that states that, of all the different types of cells in the brain, neurons are the only ones that fire electric impulses.

    These findings show that human cells other than neurons can fire electrical impulses. Since there is an estimated 100 million of these OPCs in the adult brain, the electrical contributions of these cells should be further studied.

    Moreover, the comprehensive data analyses revealed that the spiking hybrid cells in glioma tumors had properties of both neurons and OPC cells. Interestingly, they found non-tumor cells that are neuron-glia hybrids, suggesting that this hybrid population not only plays a role in glioma growth but also contributes to healthy brain function. The findings also suggest that the proportion of spiking hybrid cells in glioma may have a prognostic value.

    Part1

  • Dr. Krishna Kumari Challa

    The data shows that the more of these spiking hybrid glioma cells a patient has, the better the survival outcome. This information is of great value to patients and their doctors.

     Integrated electrophysiological and genomic profiles of single cells reveal spiking tumor cells in human glioma, Cancer Cell (2024). DOI: 10.1016/j.ccell.2024.08.009www.cell.com/cancer-cell/fullt … 1535-6108(24)00308-8

    Part 2

  • Dr. Krishna Kumari Challa

    Neuroscientists uncover serotonin's role in resilience

    The simple act of observing others cope with a traumatic experience can increase our capacity for resilience and prevent the pathological states that can result from it, notably depression. Neuroscientists  have demonstrated the presence of this "emotional contagion" in mice, and successfully deciphered its mechanism.

    The neurotransmitter serotonin, released in a brain structure called the habenula, has been shown to be the key to resilience.

    This discovery, published in Science, revisits the role of serotonin and opens up new perspectives, notably for understanding depression and its treatment.

    Human beings have the ability to cope with aversive experiences while continuing to live a normal life. This ability is known as resilience. However, some individuals are more vulnerable to traumatic events. They develop a loss of motivation and drive, which are hallmarks of depression.

    Promoting resilience in such people at risk could counter their vulnerability and function as a preventive practice against the possible emergence of a pathological state. But there are still too many unknowns for resilience to be used as a preventive practice.

    There is a lack of clinical tools or underlying mechanisms to promote this type of conditioning capable of fostering a resilient reaction as in healthy people. To achieve this, we need to understand the brain function behind adversity.

    To explore the underlying brain mechanisms, the neuroscientists first designed an experimental model capable of promoting resilience and measuring its consequences on the appearance of pathological traits following trauma.

    They started from the recognized fact that simply observing the emotional experiences of others helps us to learn from them. It's a phenomenon known as emotional contagion, and it engages resilience.

    To achieve this, an "observer" mouse was placed close to a mouse subjected to small electric shocks to the paws. This simple task protected the majority of the observer mice from developing pathological states of depression when they were subsequently exposed to this unpleasant experience themselves.

    This was not the case for mice who had not witnessed the traumatic experiences of their fellow companions. The scientists concluded that the simple act of observing others cope with a traumatic experience increases one's own capacity for resilience and helps guard against possible pathological consequences.

    Part 1

  • Dr. Krishna Kumari Challa

    Following the discovery of this behavioral principle, the neuroscientists successfully identified the brain mechanism mediating it. They focused on the habenula, a tiny cerebral structure located at the heart of the brain, known to participate in emotional and sensory processing, and to regulate neurotransmitters associated with depression, notably serotonin.

    To achieve this, they specifically developed imaging tools to track this molecule in mice.
    It is very difficult to measure the variation of serotonin in the brain. Thanks to a biosensor developed by some of the team members, the scientists were able to identify the key mechanism.
    Recordings made during behavioral experiments revealed that emotional contagion coincided with a lasting change in the functioning of neurons in the habenula, together with an increase in serotonin release in this region.
    By artificially altering the dynamics of serotonin levels, the research team was able to demonstrate that its non-increase not only undermines the long-lasting neuronal activity change in the habenula, but also the ability of mice to foster resilience following adversity.

    A common denominator between the mechanism of resilience after adversity discovered in this study and that of depression is serotonin. Many antidepressants target serotonin to increase its concentration in the brain. Here, neuroscientists show that a transient, localized increase in the habenula can prevent the onset of apathetic behavior following a traumatic experience.

    This  discovery could also pave the way for new therapeutic applications relevant to depression.

    Sarah Mondoloni et al, Serotonin release in habenula during emotional contagion promotes resilience, Science (2024). DOI: 10.1126/science.adp3897www.science.org/doi/10.1126/science.adp3897


    Part 2

  • Dr. Krishna Kumari Challa

    100-fold improvement in sight seen after gene therapy trial

    The vision of people with a rare inherited condition that causes them to lose much of their sight early in childhood was 100 times better after they received gene therapy to address the genetic mutation causing it. Some patients even experienced a 10,000-fold improvement in their vision after receiving the highest dose of the therapy, according to researchers from the Perelman School of Medicine at the University of Pennsylvania who co-led the clinical trial published in The Lancet.

    That 10,000-fold improvement is the same as a patient being able to see their surroundings on a moonlit night outdoors as opposed to requiring bright indoor lighting before treatment.

    One patient reported for the first time being able to navigate at midnight outdoors only with the light of a bonfire.

    A total of 15 people participated in the Phase I/II trial, including three pediatric patients. Each patient had Leber congenital amaurosis as the result of mutations in the GUCY2D gene, which is essential to producing proteins critical for vision. This specific condition, which affects less than 100,000 people worldwide and is abbreviated as LCA1, causes a significant amount of vision loss as early as infancy.

    All subjects had severe vision loss with their best measure of vision being equal or worse than 20/80—meaning if a typically-sighted person could see an object clearly at 80 feet, these patients would have to move up to at least 20 feet to see it.

    Glasses provide limited benefit to these patients because they correct abnormalities in the optical focusing ability of the eye, and are unable to address medical causes of vision loss, such as genetic retinal diseases like LCA1.

    Part 1

  • Dr. Krishna Kumari Challa

    The trial tested different dosage levels of the gene therapy, ATSN-101, which was adapted from the AAV5 microorganism and was surgically injected under the retina.

    For the first part of the study, cohorts of three adults each received one of the three different dosages: Low, mid, and high. Evaluations were held between each level of dosage to ensure that they were safe before upping the dosage for the next cohort.

    A second phase of the study involved only administering the high dosage levels to both an adult cohort of three and a pediatric cohort of three, again after safety reviews of the previous cohorts.

    Improvements were noticed quickly, often within the first month, after the therapy was applied and lasted for at least 12 months. Observations of participating patients are also ongoing. Three of six high-dosage patients who were tested to navigate a mobility course in varying levels of light achieved the maximum-possible score. Other tests used eye charts or measured the dimmest flashes of light patients perceived in a dark environment.

    Of the nine patients who received the maximum dosage, two had a 10,000-fold improvement in vision.
    Primarily, the study sought to determine the safety of the gene therapy and its varying dosage levels. Researchers did find some patients had side effects, but the overwhelming majority were related to the surgical procedure itself.
    The most common side effect was conjunctival hemorrhage, the breakage of small blood vessels underneath the clear surface of the eye, which healed. Two patients had eye inflammation that was reversed with a course of steroids. No serious side effects were related to the study drug.
    Approval of this experimental medicine for clinical use requires another trial, where participants are randomized to a treatment dose and both patients and those investigating the trial not knowing who gets what. Through that, any possible bias in results could be avoided.

    Safety and efficacy of ATSN-101 in patients with Leber congenital amaurosis caused by biallelic mutations in GUCY2D: a phase 1/2, multicentre, open-label, unilateral dose escalation study, The Lancet (2024). www.thelancet.com/journals/lan … (24)01447-8/fulltext

    Part 2

  • Dr. Krishna Kumari Challa

    How aging immune system fuels cancer growth

    Why is aging the biggest risk factor for cancer? A new study reveals how an aging immune system spurs tumor growth, offering new insights into cancer prevention and treatment, especially for older adults.

    Details on the findings are reported in the September 5 Online First Release of Science.

    Cancer is a disease that becomes increasingly common as we age, with the risk rising sharply after the age of 60. Many theories have been proposed, including the cumulative effects of environmentally-induced damage and genetic mutations, but there has been little concrete data explaining why aging drives cancer.

    In preclinical models,  a research team found that anakinra, a drug typically used for inflammatory conditions such as rheumatoid arthritis, can be repurposed to block harmful signals between early lung cancer lesions and the bone marrow. This is critical, say the investigators, because as the immune system ages, it creates harmful inflammation that can drive cancer development.

    As the immune system ages, it triggers harmful inflammation that can drive cancer growth––by promoting the accumulation of pro-tumor macrophages, a type of immune cell that suppresses the immune effector cells that normally kill tumor cells. This weakens the body's ability to fight cancer.

    The researchers found that by blocking specific inflammatory pathways, especially those involving molecules called interleukin-1⍺ (IL-1⍺) and IL-1β, this damaging process could be reversed in mouse models, offering a potential new approach to preventing cancer development in humans.

     

    As part of the study, the research team used mouse models to investigate how aging affects cancer progression. They injected tumor cells into mice and observed that lung, pancreatic, and colonic cancer grew more rapidly in older mice compared to younger ones. Using bone marrow transplants from either young or old mice, the investigators simulated the effects of the immune system's aging. The team found that an aged immune system accelerates cancer growth, even in young mice. More strikingly, they found that rejuvenating the immune system significantly reduced cancer growth in older mice.

    Using high-dimensional analysis of murine and human cancer tissues, the team identified specific cells and immune-related factors that accelerate cancer growth in the elderly. They then successfully blocked these factors, specifically IL-1⍺/β, demonstrating that inhibiting these molecules can reduce cancer growth in aged mice.

    This study shows that an aged immune system promotes cancer progression, independent of the age of the cancer cells or the surrounding tissue. We've long suspected that inflammation can suppress anti-tumor immunity, particularly in older individuals and cancer patients. However, this is the first robust evidence proving that chronic inflammation from an aging immune system predisposes to cancer. 

    This study reveals that targeting the aging immune system could significantly reduce cancer risk in older adults. It suggests that enhancing the immune response through immunotherapy might be more effective than directly targeting tumors. 

    Part1

  • Dr. Krishna Kumari Challa

    The ongoing trials are investigating whether targeting the immune system can prevent cancer progression, while the researchers continue to explore additional therapeutic targets.

     Matthew D. Park et al, Hematopoietic aging promotes cancer by fueling IL-1⍺-driven emergency myelopoiesis, Science (2024). DOI: 10.1126/science.adn0327www.science.org/doi/10.1126/science.adn0327

    Part 2

  • Dr. Krishna Kumari Challa

    A new technique makes skin invisible

    Researchers have developed a new way to see organs within a body by rendering overlying tissues transparent to visible light. The counterintuitive process—a topical application of food-safe dye—was reversible in tests with animal subjects, and may ultimately apply to a wide range of medical diagnostics, from locating injuries to monitoring digestive disorders to identifying cancers.

    The  researchers published the research, titled "Achieving optical transparency in live animals with absorbing molecules," in the Sept. 6, 2024, issue of Science.

    Animation depicting the tissue transparency effect and how it might appear if tested with humans in the future. The latter part of the animation shows how photons interact with tissues at the cellular level, both with and without FD & C Yellow 5 saturation. Credit: Keyi "Onyx" Li/U.S. National Science Foundation

    Part 1

  • Dr. Krishna Kumari Challa

    To master the new technique, the researchers developed a way to predict how light interacts with dyed biological tissues.

    Those predictions required a deep understanding of light scattering, as well as the process of refraction, where light changes speed and bends as it travels from one material into another.

    Scattering is the reason we cannot see through our body: Fats, fluids within cells, proteins, and other materials each have a different refractive index, a property that dictates how significantly an incoming light wave will bend.

    In most tissues, those materials are closely compacted together, so the varied refractive indices cause light to scatter as it passes through. It is the scattering effect that our eyes interpret as opaque, colored, biological materials.

    The researchers realized if they wanted to make biological material transparent, they had to find a way to match the different refractive indices so light could travel through unimpeded.

    Building upon fundamental insights from the field of optics, the researchers realized dyes that are the most effective at absorbing light can also be highly effective at directing light uniformly through a wide range of refractive indices.

    One dye the researchers predicted would be particularly effective was tartrazine, the food dye more commonly known as FD & C Yellow 5. It turns out, they were correct: when dissolved into water and absorbed into tissues, tartrazine molecules are perfectly structured to match refractive indices and prevent light from scattering, resulting in transparency.

    The researchers first tested their predictions with thin slices of chicken breast. As tartrazine concentrations increased, the refractive index of the fluid within the muscle cells rose until it matched the refractive index of the muscle proteins—the slice became transparent.

    Then, the researchers gently rubbed a temporary tartrazine solution on mice. First, they applied the solution to the scalp, rendering the skin transparent to reveal blood vessels crisscrossing the brain. Next, they applied the solution to the abdomen, which faded within minutes to show contractions of the intestine and movements caused by heartbeats and breathing.

    The technique resolved features at the scale of microns, and even enhanced microscope observations. When the dye was rinsed off, the tissues quickly returned to normal opacity. The tartrazine did not appear to have long-term effects, and any excess was excreted in waste within 48 hours.

    The researchers suspect that injecting the dye should lead to even deeper views within organisms, with implications for both biology and medicine.

     Zihao Ou et al, Achieving optical transparency in live animals with absorbing molecules, Science (2024). DOI: 10.1126/science.adm6869www.science.org/doi/10.1126/science.adm6869

  • Dr. Krishna Kumari Challa

    The flaming carcasses of electrocuted birds keep starting wildfires

    In the past two months alone, the flaming carcasses of electrocuted birds have ignited at least three wildfires in Colorado.

    While the phenomenon sounds straight out of a cartoon, it's actually more common than you'd think, experts said. It's a big enough problem that electric utility companies brainstorm efforts to mitigate bird electrocution.

    Researchers found no coordinated records or data illustrating how frequently electrocuted birds dropping off power lines spark wildfires, so they sifted through Google searches of avian-induced fires in the United States from 2014 to 2018 and found 44 reported cases.

    California had the highest number of incidents at 15. Colorado had two in 2016—one in Littleton and one in Berthoud, the study found.

    However, in July and August of this year, Colorado's Front Range has been the scene of at least three reported bird combustions resulting in wildfires.

    Cities'   infrastructure can be attractive to birds for roosting and building nests and can post a collision or electrocution hazard to birds.

    There are a couple of reasons why birds are increasingly meeting an end better suited for the "Final Destination" films.

    It's partially because of climate change. An electrocuted bird is more likely to ignite a fire if conditions are dry and the regions face drought like conditions. 

    In addition to climate, there is the human introduction of electrical utility equipment into the environment. 

    Part 1

  • Dr. Krishna Kumari Challa

    Birds can sit on one wire, no problem. But if a bird touches a second wire, it opens a path of electricity right through the bird's body, with a resulting zap that can be potent enough to send the bird up in flames.

    Larger birds like hawks and eagles can be more at risk of electrocution because their wider wingspans put them at greater risk of touching two different wires simultaneously.
    Sometimes smaller birds on the hunt for bugs will drive their beaks under insulated coverings in hopes of a snack, only to find an electrical jolt instead.
    Source: MediaNews Group, Inc. Distributed by Tribune Content Agency, LLC.
    Part 2
    There are ways to design power poles and their accompanying structures to make them less susceptible to bird electrocution.
    For new electrical poles designers can ensure enough space between "energized components" to allow birds to exist without touching two electrical components at once.

  • Dr. Krishna Kumari Challa

    Outer solar system is more populated than previously thought
    Survey observations using the Subaru Telescope's ultra-widefield prime focus camera have revealed that there may be a population of small bodies further out in the Kuiper Belt waiting to be discovered.
    The results, which are important for an understanding of the formation of the solar system, were obtained through an international collaboration between the Subaru Telescope and the New Horizons spacecraft traveling through the outer solar system.
    NASA's New Horizons spacecraft was launched in 2006 with the critical mission of observing the surfaces of outer solar system bodies up close for the first time in human history; it successfully completed a flyby of the Pluto system in 2015, and in 2019 it made a flyby of one of the Kuiper Belt objects, (486958) Arrokoth.

    There have been five spacecraft that have flown to the outer solar system (including New Horizons), but New Horizons is the only spacecraft that has flown through the Kuiper Belt while observing Kuiper Belt objects.

    When observing Kuiper Belt objects from the ground, we can only observe them at small solar phase angles (the angle between the sun, the object, and the observer). On the other hand, when observing a Kuiper Belt object from a spacecraft in the Kuiper Belt, the same object can be observed at various phase angles and its reflection characteristics can be used to estimate the surface properties of the object. This is something only New Horizons can do.

    However, the camera on the spacecraft has a narrow field-of-view and cannot discover Kuiper Belt objects on its own. This is where the Subaru Telescope comes in. The Subaru Telescope uses its wide-field camera to find many Kuiper Belt objects and then narrow down the list of objects that the spacecraft can fly by and observe. This collaboration between New Horizons and the Subaru Telescope began in 2004.
    Part 1

  • Dr. Krishna Kumari Challa

    For observations conducted during 2004–2005 with Subaru Telescope's prime focus camera (Suprime-Cam), due to the orbital relationship between Pluto and the spacecraft, an area near the center of the Milky Way galaxy got caught in the background of the search area for Kuiper Belt objects.

    Although it was extremely difficult to search for solar system objects with many background stars, the research team was able to find 24 Kuiper Belt objects.

    Unfortunately, the Kuiper belt objects so far found during this observation require too much fuel for the spacecraft to flyby, but new ones at great distance may fall within the available fuel reach of New Horizons. In 2020, deeper observations began with Hyper Suprime-Cam (HSC) on the Subaru Telescope, and by 2023, there had been 239 Kuiper Belt objects discovered.

    "The most exciting part of the HSC observations was the discovery of 11 objects at distances beyond the known Kuiper Belt.
    Many of the objects discovered with HSC are located at distances of 30–55 astronomical units (au) from the sun (1 au corresponds to the distance between the sun and Earth) and are thought to be within the known Kuiper Belt.

    Marc W. Buie et al, The New Horizons Extended Mission Target: Arrokoth Search and Discovery, arXiv (2024). DOI: 10.48550/arxiv.2403.04927

    Wesley C. Fraser et al, Candidate Distant Trans-Neptunian Objects Detected by the New Horizons Subaru TNO Survey, arXiv (2024). DOI: 10.48550/arxiv.2407.21142

    Part 2

  • Dr. Krishna Kumari Challa

    Excessive light pollution may increase risk of Alzheimer's, especially in younger people

    In some places around the globe, the lights never go off. Streetlights, roadway lighting, and illuminated signs can deter crime, make roads safer, and enhance landscaping. Undisrupted light, however, comes with ecological, behavioral, and health consequences. 

    Researchers now  have investigated correlations between outside nightly light pollution and Alzheimer's disease (AD).

    There is a positive association between AD prevalence and exposure to light at night, particularly in those under the age of 65, the researchers showed. Nightly light pollution—a modifiable environmental factor—may be an important risk factor for AD, they say.

    The researchers studied light pollution maps of the lower 48 US states and incorporated medical data about variables known or believed to be risk factors for AD in their analysis. They generated nighttime intensity data for every state and divided them into five groups, from lowest to highest nighttime light intensity.
    Their results showed that for people aged 65 and older, AD prevalence was more strongly correlated with nightly light pollution than some other disease factors, including alcohol abuse, chronic kidney disease, depression, and obesity. Other risk factors, like diabetes, high blood pressure, and stroke were more strongly associated with AD than light pollution.
    For people aged under 65, however, the researchers found that higher nighttime light intensity was associated with a greater AD prevalence than any other risk factor examined in the study. This could suggest that younger people may be particularly sensitive to the effects of light exposure at night, the researchers said.

    It is unclear why younger people could be more vulnerable, but it could be due to individual differences in light sensitivity. Certain genotypes, which influence early-onset AD, impact the response to biological stressors which could account for increased vulnerability to the effects of nighttime light exposure. Additionally, younger people are more likely to live in urban areas and have lifestyles that may increase exposure to light at night.

    The researchers hope that their findings can help educate people about the potential risks of light at night.

    Robin M. Voigt et all, Outdoor Nighttime Light Exposure (Light Pollution) is Associated with Alzheimer's Disease, Frontiers in Neuroscience (2024). DOI: 10.3389/fnins.2024.1378498

  • Dr. Krishna Kumari Challa

    Hijacking the command center of the cell: Nuclear parasites

    Most animals live in intimate relationships with bacteria. Some of these bacteria live inside the cells of their hosts, but only very few are able to live inside cell organelles (structures inside the cell, like organs in the body). One group of bacteria have figured out how to colonize the nuclei of their hosts, a remarkable feat given that the nucleus is the control center of the cell.

    To date, nothing is known about the molecular and cellular processes that these intranuclear bacteria use to infect and reproduce in animal hosts. A group of scientists now presents the first in-depth analysis of an intranuclear parasite of animals in a study published in Nature Microbiology.

    This intranuclear parasite, Candidatus endonucleobacter, infects the nuclei of deep-sea mussels from hydrothermal vents and cold seeps around the world. A single bacterial cell penetrates into the mussels' nucleus and then reproduces to over 80,000 cells, causing the nucleus to swell to 50 times its original size.

    Using a suite of molecular and imaging methods, the scientists revealed that Ca. endonucleobacter lives on sugars, lipids and other cell components from its host. It does not digest its host nucleic acids, like many other intranuclear bacteria. This feeding strategy ensures that the host cell functions long enough to provide Ca. endonucleobacter with the nutrients it needs to reproduce in such massive numbers.

    A common response of animal cells to infection is apoptosis—a suicide program that cells initiate when they are damaged or infected by bacteria or viruses.

    Interestingly, these bacteria have come up with a sophisticated strategy to keep their host cells from killing themselves. They produce proteins that suppress apoptosis called inhibitors of apoptosis (IAPs).

    An arms race for the control of cell death then ensues: As the bacteria produce more and more IAPs, the host cell ramps up its production of proteins that induce apoptosis. Eventually, after the parasite has had enough time to multiply in masses, the host cell ruptures, releasing the bacteria and allowing them to infect new host cells.

    This discovery expands our understanding of host-microbe interactions and highlights the complex strategies parasites have evolved to thrive in their hosts.

    These findings could have broader implications for studying parasitic infections and immune evasion strategies in other organisms.

     An intranuclear bacterial parasite of deep-sea mussels expresses apoptosis inhibitors acquired from its host, Nature Microbiology (2024). DOI: 10.1038/s41564-024-01808-5

  • Dr. Krishna Kumari Challa

    AI helps distinguish dark matter from cosmic noise

    Dark matter is the invisible force holding the universe together—or so we think. It makes up about 85% of all matter and around 27% of the universe's contents, but since we can't see it directly, we have to study its gravitational effects on galaxies and other cosmic structures. Despite decades of research, the true nature of dark matter remains one of science's most elusive questions.

    According to a leading theory, dark matter might be a type of particle that barely interacts with anything else, except through gravity. But some scientists think these particles could occasionally interact with each other, a phenomenon known as self-interaction. Detecting such interactions would offer crucial clues about dark matter's properties.

    However, distinguishing the subtle signs of dark matter self-interactions from other cosmic effects, like those caused by active galactic nuclei (AGN)—the supermassive black holes at the centers of galaxies—has been a major challenge. AGN feedback can push matter around in ways that are similar to the effects of dark matter, making it difficult to tell the two apart.

    In a significant step forward, astronomers   have developed a deep-learning algorithm that can untangle these complex signals. The research is published in Nature Astronomy.

    Their AI-based method is designed to differentiate between the effects of dark matter self-interactions and those of AGN feedback by analyzing images of galaxy clusters—vast collections of galaxies bound together by gravity. The innovation promises to greatly enhance the precision of dark matter studies.

    A deep-learning algorithm to disentangle self-interacting dark matter and AGN feedback models, Nature Astronomy (2024). DOI: 10.1038/s41550-024-02322-8

  • Dr. Krishna Kumari Challa

    Tiny magnetic robots could treat bleeds in the brain

    Researchers have created nanoscale robots which could be used to manage bleeds in the brain caused by aneurysms. The development could enable precise, relatively low-risk treatment of brain aneurysms, which cause around 500,000 deaths globally each year. The medical condition—a blood-filled bulge on a brain artery that can rupture and cause fatal bleeds—can also lead to stroke and disability.

    The study points to a future where tiny robots could be remotely controlled to carry out complex tasks inside the human body—such as targeted drug delivery and organ repair—in a minimally invasive way, researchers say.

    The researchers engineered magnetic nanorobots—about a twentieth the size of a human red blood cell—comprising blood-clotting drugs encased in a protective coating, designed to melt at precise temperatures. The work is published in the journal Small.

    In lab tests, several hundred billion such bots were injected into an artery and then remotely guided as a swarm, using magnets and medical imaging, to the site of an aneurysm.

    Magnetic sources outside the body then cause the robots to cluster together inside the aneurysm and be heated to their melting point, releasing a naturally occurring blood-clotting protein, which blocks the aneurysm to prevent or stem bleeding into the brain.

    The international team of researchers successfully tested their devices in model aneurysms in the lab and in a small number of rabbits.

    The team says that nanorobots show potential for transporting and releasing drug molecules to precise locations in the body without risk of leaking into the bloodstream—a key test of the technology's safety and efficacy.

    The study could pave the way for further developments towards trials in people.

    Jienan Wang et al, Nanoarchitectonic Engineering of Thermal‐Responsive Magnetic Nanorobot Collectives for Intracranial Aneurysm Therapy, Small (2024). DOI: 10.1002/smll.202400408

  • Dr. Krishna Kumari Challa

    Low-cost nanomaterial technology can detect cancer genes with ultra-high sensitivity

    A research team has  developed a technology that can detect cancer mutant genes in blood with the world's highest sensitivity of 0.000000001% based on plasmonic nanomaterials for optical signal amplification. The team tested blood samples from lung cancer patients (stages 1-4) and healthy individuals for EGFR mutations and achieved a diagnostic accuracy of 96%.

    The work is published in the journal Small Science.

    Previously utilized genetic analysis technologies had low analytical sensitivity to detect mutated genes compared to normal genes, making it difficult to accurately diagnose early-stage cancer patients. In addition, it was difficult to establish a quick treatment strategy and apply it to screening tests due to the high cost and long time required for analysis and the need for special equipment.

    To overcome these challenges, the research team developed a low-cost analysis technology that can analyze various cancer mutations within the target gene region within one hour with an ultra-high sensitivity of 0.000000001%. This technology boasts the world's highest level of sensitivity, which is 100,000 times better than the highest level of 0.0001% among reported technologies, and through this, the possibility of early diagnosis was confirmed using the blood of lung cancer patients.

    This technology combines nanomaterial technology that significantly improves the fluorescence signal, and primer/probe design that suppresses the fluorescence signal of normal genes, amplifying only the fluorescence signal of cancer mutant genes. This is because the accurate detection of even very small amounts of cancer mutated genes requires not only strong fluorescent signal expression technology but also precise discrimination of fine fluorescent signals.

    The team fabricated a biochip in the form of a microarray capable of simultaneously detecting three mutant genes of EGFR (deletion, insertion, and point mutations) on a plasmonic substrate made of three-dimensional, high-density gold nanostructures. After evaluating the clinical performance of 43 domestic lung cancer patients (stages 1 to 4) and 40 normal groups, a clinical sensitivity of 93% for lung cancer patients and a clinical specificity of 100% for the normal group were confirmed.

    This technology can play an important role in not only early diagnosis and detection of recurrence of cancer, but also in monitoring treatment effectiveness and establishing personalized treatment plans. In addition, liquid biopsy using blood is possible as an alternative to surgical tissue biopsy, reducing the burden on patients and simplifying the examination process. It can also serve as a regular screening test, ultimately improving the quality of cancer management and treatment.

    Ji Young Lee et al, Highly Sensitive 3D‐Nanoplasmonic‐Based Epidermal Growth Factor Receptor Mutation Multiplex Assay Chip for Liquid Biopsy, Small Science (2024). DOI: 10.1002/smsc.202400101

  • Dr. Krishna Kumari Challa

    Researchers make sound waves travel in one direction only, with implications for electromagnetic wave technology

    Researchers at ETH Zurich have managed to make sound waves travel only in one direction. In the future, this method could also be used in technical applications with electromagnetic waves.

    Water, light and sound waves usually propagate in the same way forward as in a backward direction. As a consequence, when we are speaking to someone standing some distance away from us, that person can hear us as well as we can hear them. This is useful when having a conversation, but in some technical applications one would prefer the waves to be able to travel only in one direction—for instance, in order to avoid unwanted reflections of light or microwaves.

    Ten years ago, researchers succeeded in suppressing sound wave propagation in the backward direction; however, this also attenuated the waves traveling forwards.

    A team of researchers has now developed a method for preventing sound waves from traveling backward without deteriorating their propagation in the forward direction.

    The basis of this one-way street for sound waves are self-oscillations, in which a dynamical system periodically repeats its behavior.

    In the future, this method, which has recently been published in Nature Communications, could also be applied to electromagnetic waves.

    Tiemo Pedergnana et al, Loss-compensated non-reciprocal scattering based on synchronization, Nature Communications (2024). DOI: 10.1038/s41467-024-51373-y

    Part 2

  • Dr. Krishna Kumari Challa

    1.8 Billion Years of Plate Tectonics

    Using information from inside the rocks on Earth's surface, researchers have reconstructed the plate tectonics of the planet over the last 1.8 billion years.

    It is the first time Earth's geological record has been used like this, looking so far back in time. This has enabled us to make an attempt at mapping the planet over the last 40% of its history, which you can see in the animation below.

    The work is now published in the open-access journal Geoscience Frontiers.

    Mapping our planet through its long history creates a beautiful continental dance—mesmerizing in itself and a work of natural art.

    It starts with the map of the world familiar to everyone. Then India rapidly moves south, followed by parts of Southeast Asia as the past continent of Gondwana forms in the Southern Hemisphere.

    Around 200 million years ago (Ma or mega-annum in the reconstruction), when the dinosaurs walked the earth, Gondwana linked with North America, Europe and northern Asia to form a large supercontinent called Pangea.

    Then, the reconstruction carries on back through time. Pangea and Gondwana were themselves formed from older plate collisions. As time rolls back, an earlier supercontinent called Rodinia appears. It doesn't stop here. Rodinia, in turn, is formed by the break-up of an even older supercontinent called Nuna about 1.35 billion years ago.

    Part 1

  • Dr. Krishna Kumari Challa

    Among the planets in the solar system, Earth is unique for having plate tectonics. Its rocky surface is split into fragments (plates) that grind into each other and create mountains, or split away and form chasms that are then filled with oceans.

    Apart from causing earthquakes and volcanoes, plate tectonics also pushes up rocks from the deep earth into the heights of mountain ranges. This way, elements which were far underground can erode from the rocks and end up washing into rivers and oceans. From there, living things can make use of these elements.

    Among these essential elements is phosphorus, which forms the framework of DNA molecules, and molybdenum, which is used by organisms to strip nitrogen out of the atmosphere and make proteins and amino acids—building blocks of life.

    Plate tectonics also exposes rocks that react with carbon dioxide in the atmosphere. Rocks locking up carbon dioxide is the main control on Earth's climate over long time scales—much, much longer than the tumultuous climate change we are responsible for today.

    Mapping the past plate tectonics of the planet is the first stage in being able to build a complete digital model of Earth through its history.

    Xianzhi Cao et al, Earth's tectonic and plate boundary evolution over 1.8 billion years, Geoscience Frontiers (2024). DOI: 10.1016/j.gsf.2024.101922

  • Dr. Krishna Kumari Challa

    Researchers discover an effective and environment-friendly disinfectant

    A widely used disinfectant worldwide, chloroxylenol, has been associated with eco-toxicological threats in water environments due to its relatively high chemical stability and massive consumption. Researchers at the School of Engineering of the Hong Kong University of Science and Technology (HKUST) have discovered a promising alternative known as 2,6-dichlorobenzoquinone (2,6-DCQ), which works more effectively in combating certain common bacteria, fungi and viruses, and can be rapidly degraded and detoxified in receiving waters.

    Their findings have been published in Nature Communications.

    Jiarui Han et al, An effective and rapidly degradable disinfectant from disinfection byproducts, Nature Communications (2024). DOI: 10.1038/s41467-024-48752-w

  • Dr. Krishna Kumari Challa

    Study of older patients suggests 1 in 5 cases of dementia may be attributable to vision impairment

    Prior research has found that there may be a connection between hearing loss in aging people and the onset of dementia. In a new study, a team of health care researchers and geriatric specialists  surveyed patient health care records and reported that approximately 1 in 5 cases of dementia could also be attributable to vision impairment in community-dwelling  adults aged 71 years or older.

    The paper is published in the journal JAMA Ophthalmology.

    Scientists still do not know what causes dementia, but they strongly suspect that it might be tied to several factors, one of which might be sensory degradation. As the senses lose their sharpness, the hypothesis proposes, the brain must work harder to make sense of the external environment, all while undergoing its own aging process.

    The result could be loss of cognitive and memory abilities. In this new effort, the researchers looked for such evidence in people over the age of 71 who have experienced at least one of three main types of vision impairment: near or distance acuity, or contrast sensitivity.

    They found that approximately 19% of dementia cases could be attributable to one or more types of vision loss. This, they note, suggests that dementia could have been prevented in nearly 20% of cases if loss of vision had been addressed. They note that prior studies have shown that approximately 90% of vision problems in older people are correctable through glasses or surgery.

    The research team acknowledges that their results are based on associations rather than proof because there is no way to prove any single cause of dementia. But they also suggest that the associations they found make a strong case for it.

    More information: Jason R. Smith et al, Vision Impairment and the Population Attributable Fraction of Dementia in Older Adults, JAMA Ophthalmology (2024). DOI: 10.1001/jamaophthalmol.2024.3131

    **

  • Dr. Krishna Kumari Challa

    Tidal Locking | Why Do We Only See One Side of the Moon?

  • Dr. Krishna Kumari Challa


    Bat loss linked to death of human babies
    When insect-eating bats are wiped out by ‘white nose syndrome’, farmers turn to pesticides for pest control — possibly leading to knock-on effects for human health. Researchers compared counties in the northeastern United States where the white nose fungus had killed most bats to those areas where the disease hadn’t yet spread. In places where bat populations had crashed, farmers used 31% more insecticides and infant deaths not due to accidents or homicides rose by 8% — numbers that the authors suggest might be linked. Where bats remained, there was no change in pesticide use or infant mortality.

    The study is the “most convincing evidence to date” linking economic and health impacts with dramatic losses of a wild species.

    Bats are good to have around a farm. They provide free pest control, with some species consuming 40% of their body weight each night in insects. The value of this service has been estimated at between $4 billion and $53 billion per year. So, it’s logical to assume farmers might compensate for a loss of bats by spraying more insecticides.

    Infant mortality in all the counties: In places where the bat populations had crashed, deaths due to accident or homicides stayed the same. But other deaths, such as those caused by disease or birth defects, rose 8%. In counties with healthy bat populations, the numbers didn’t shift one way or another.

    Several lines of evidence connect pesticides and other agrochemicals to human health risks.

    That is why we say we - all living beings - are all dependent on one another for our survival.

    https://www.science.org/doi/10.1126/science.adg0344

    https://www.science.org/content/article/my-jaw-dropped-bat-loss-lin...

  • Dr. Krishna Kumari Challa

    Bacteria in your mouth Reproduce in a rare way

    The microbial ecosystem nesting in your mouth is giving scientists a rare tool to learn about how bacteria multiply. One of the most common bacteria living in your dental plaque, a filamentous bacterium called Corynebacterium matruchotii, divides not into two daughter cells like most cell divisions but multiple new microbes in a rarer process called multiple fission.

    A team of scientists observed single C. matruchotii cells dividing up into up to 14 new cells – a feat that can tell us how these organisms form the scaffolding that supports the hosts of other microbes that are dwelling in your mouth.

    The Corynebacterium cells in dental plaque are like a big, bushy tree in the forest; they create a spatial structure that provides the habitat for many other species of bacteria around them.

    Most bacteria and archaea reproduce via an asexual process called binary fission. The genetic material divides, and the cell itself then divides, resulting in two organisms where there was one.

    Researchers saw the unusual cell division of C. matruchotii was not the normal binary kind, but much more prolific. And it does so in a very strange way.

    First, the filament elongates at just one end, growing much longer than the usual size of the cell. It does so at a rate five times faster than other, closely related Corynebacterium species that live in the nose or on the skin.

    Then, a number of dividing walls called septa form simultaneously, before the cell breaks apart into between 3 and 14 complete daughter cells.

    Thanks to this strange process, a colony of C. matruchotii can grow very fast indeed, up to half a millimeter per day – which might help explain why plaque starts to return to your teeth within hours, no matter how strenuously you clean them.

    Another interesting thing about C. matruchotii that might drive its strange growth and division is that it lacks a flagellum; the whip-like appendage other bacteria use to get around. Because it is fixed in place, its fast growth could be a means of exploring its environment and looking for sources of food, the researchers say.

    https://www.pnas.org/doi/10.1073/pnas.2408654121

  • Dr. Krishna Kumari Challa

    Scientists Discover Mosquitoes Are Using Infrared to Track Humans Down

    There's something about us that mosquitoes just love. In addition to our smell, and our breath, our exposed skin acts as a kind of neon sign advertising that this blood bar is open for business.

    That's because mosquitoes use infrared sensing in their antennae to track down their prey, a new study has found.
    In many parts of the world, mosquito bites are more than an irritation, capable of spreading pathogens like dengue, yellow fever, and Zika virus. Malaria, spread by the Anopheles gambiae mosquito, caused more than 600,000 deaths in 2022, according to World Health Organization statistics.

    To avoid serious disease, or even just a case of maddening itchiness, we humans are pretty keen to find ways to prevent mosquito bites.

    Research found that mosquitoes use infrared detection – along with other cues we already knew about, like a nose for the CO2 in our breath, and certain body odours, to seek out hosts.

    https://www.nature.com/articles/s41586-024-07848-5

  • Dr. Krishna Kumari Challa

    A person's intelligence limits their computer proficiency more than previously thought, say researchers

    A new study has found that intelligence, in the form of general cognitive abilities such as perception, thinking and remembering, is more important than hitherto thought at predicting a person's ability to complete common tasks with a PC. The study was published in the International Journal of Human-Computer Studies in August 2024.

    This research findings are the first clear proof that cognitive abilities have a significant, independent and wide-ranging effect on people's ability to use a computer. Contrary to what was previously thought, cognitive abilities are as important as previous experience of computer use.

    The findings have implications for digital equality, say the researchers, because everyday user interfaces have simply become too complex to use. Practice alone is no longer enough, with intelligence becoming an equally critical factor in predicting performance in computer tasks.

    "It is clear that differences between individuals cannot be eliminated simply by means of training; in the future, user interfaces need to be streamlined for simpler use. This age-old goal has been forgotten at some point, and awkwardly designed interfaces have become a driver for the digital divide. We cannot promote a deeper and more equal use of computers in society unless we solve this basic problem, say the researchers. 

    However, the research findings also show that age remains the most important factor in how well an individual can use applications. Older people clearly took more time to complete their tasks, and they also felt that the assignments were more burdensome.

     Erik Lintunen et al, Cognitive abilities predict performance in everyday computer tasks, International Journal of Human-Computer Studies (2024). DOI: 10.1016/j.ijhcs.2024.103354

  • Dr. Krishna Kumari Challa

    Newly discovered antibody protects against all COVID-19 variants

    Researchers have discovered an antibody able to neutralize all known variants of SARS-CoV-2, the virus that causes COVID-19, as well as distantly related SARS-like coronaviruses that infect other animals.

    As part of a new study on hybrid immunity to the virus, the large, multi-institution research team discovered and isolated a broadly neutralizing plasma antibody, called SC27, from a single patient. Using technology developed over several years of research into antibody response, the research team obtained the exact molecular sequence of the antibody, opening the possibility of manufacturing it on a larger scale for future treatments.

    The discovery of SC27, and other antibodies like it in the future, will help us better protect the population against current and future COVID variants.

    Protective antibodies bind to a part of the virus called the spike protein that acts as an anchor point for the virus to attach to and infect the cells in the body. By blocking the spike protein, the antibodies prevent this interaction and, therefore, also prevent infection.

    Scientists after verifying  the properties of SC27 found that it recognized the different characteristics of the spike proteins in the many COVID variants.

    In addition to the discovery of this antibody, the research found that hybrid immunity—a combination of both infection and vaccination—offers increased antibody-based protection against future exposure compared with infection or vaccination alone.

    The researchers have filed a patent application for SC27.

    William N. Voss et al, Hybrid immunity to SARS-CoV-2 arises from serological recall of IgG antibodies distinctly imprinted by infection or vaccination, Cell Reports Medicine (2024). DOI: 10.1016/j.xcrm.2024.101668

  • Dr. Krishna Kumari Challa

    Scientists provided evidence for long-standing wave amplification theory

    Physicists  have tested and provided evidence for  a 50-year-old theory for the first time using electro-magnetic waves. They have shown that the energy of waves can be increased by bouncing "twisted waves"—those with angular momentum—off of an object which is rotating in a specific way.

    This is known as the "Zel'dovich effect," named after Soviet physicist Yakov Zel'dovich who developed a theory based on this idea in the 1970s. Until now, it was believed to be unobservable with electromagnetic fields.

    The Zel'dovich effect works on the principle that waves with angular momentum, that would usually be absorbed by an object, actually become amplified by that object instead, if it is rotating at a fast enough angular velocity. In this case, the object is an aluminum cylinder and it must rotate faster than the frequency of the incoming radiation.

    Although physicists successfully tested this theory in sound waves a few years ago, but until this most recent experiment it hadn't been proven with electromagnetic waves. Using relatively simple equipment—a resonant circuit interacting with a spinning metal cylinder—and by creating the specific conditions required, they have now been able to do this.

    M. C. Braidotti et al, Amplification of electromagnetic fields by a rotating body, Nature Communications (2024). DOI: 10.1038/s41467-024-49689-w

  • Dr. Krishna Kumari Challa

    Newly identified biomarkers could reveal risk factors for sudden infant death syndrome

    Researchers  are getting closer to being able to predict sudden infant death syndrome, or SIDS.

    In a study appearing in JAMA Pediatrics, they have identified signals in the metabolic system of infants who died of SIDS.

    This study suggests that metabolic factors may play a crucial role in SIDS. These patterns could help identify children at higher risk, potentially saving lives in the future.

    Each year about 1,300 infants under the age of 1 die from SIDS, and researchers still aren't sure what causes these unexpected deaths. What they do know is that there are likely multiple factors that play a role, including inadequate prenatal care, smoking and alcohol use during pregnancy, structural racism and air pollution. Male babies have a higher rate of SIDS than girls.

    Researchers are turning to biology to look for a cause of SIDS that can be screened for at birth or targeted with medication. Investigators in this study knew from previous research that the metabolic system—how bodies process and store energy—might play a part in SIDS. They decided to examine the role of the metabolic system more closely, and compare metabolic data taken from infants as part of a routine newborn screening.

    They compared the data of infants who eventually died from SIDS with similar infants who lived.

    In the 354 infants who died from SIDS, they found that there were some metabolic biomarkers that may be associated with increased risk. For example, infants with lower levels of C-3 and elevated levels of C-14OH appear to have a higher risk of dying from SIDS. These findings are in line with previous research that has found an association between enzymes of fatty acid oxidation, like these, and SIDS.

    The scientists also found several other biomarkers that--when elevated--seemed to lead to a reduced risk of SIDS.

    JAMA Pediatrics (2024). jamanetwork.com/journals/jamap … pediatrics.2024.3033

  • Dr. Krishna Kumari Challa

    A patient tests positive for bird flu despite no known exposure to animals

    A hospitalized patient in Missouri was infected with bird flu despite having had no known contact with dairy cows or other animals associated with an ongoing outbreak, health officials said last week.

    The person tested positive for influenza A, and CDC officials later confirmed it to be bird flu. The person received antiviral medication and has since recovered and gone home, health officials said. It's not clear whether the hospitalization was caused by the bird flu infection or the person's existing health conditions.

    The case raises questions about how the person was exposed to the virus. All the previous U.S. infections were among people who worked around cows and poultry.

    The investigation is continuing, officials said.

    It's the first case detected through routine influenza surveillance rather than through targeted efforts to identify people infected with bird flu through exposure to infected cows and poultry, officials said.

    Source: News agencies

  • Dr. Krishna Kumari Challa

    Nanoscale silver exhibits intrinsic self-healing abilities without external intervention

    As an innovative concept in materials science and engineering, the inspiration for self-healing materials comes from living organisms that have the innate ability to self-heal. Along this line, the search for self-healing materials has been generally focused on "soft" materials like polymers and hydrogels. For solid-state metals, one may intuitively imagine that any form of self-healing will be much more difficult to achieve.

    While a few past studies have showcased the self-healing behavior in metals that more or less requires the assistance of external triggers (e.g., by heating, mechanical stimulus, or electron beam irradiation), whether the autonomous self-healing can occur in metal solids without any external intervention remains a scientific curiosity.

    Now in a new study published in Matter, researchers from the Institute of Physics (IOP) of the Chinese Academy of Sciences have discovered that such an intrinsic and autonomous self-healing phenomenon can occur in nanoscale silver (Ag).

    This study, which combines advanced in-situ transmission electron microscopy (TEM) with molecular dynamics (MD) simulations, reveals that nanoscale Ag can autonomously repair itself from structural damage, such as nanocracks and nanopores, without external intervention.

    This remarkable ability is observed not only at room temperature but also at frigid temperatures as low as 173 K. Notably, over the same damaging area, the repeated reversible self-healing cycles can also be achieved with the same level of efficiency.

    Jianlin Wang et al, Direct observation of autonomous self-healing in silver, Matter (2024). DOI: 10.1016/j.matt.2024.07.009

  • Dr. Krishna Kumari Challa

    Why do materials get stronger when they are deformed? Research sheds light on universal mechanisms of work hardening

    The earliest blacksmiths in the Bronze and Iron Ages figured out that when they deformed metal through bending or hammering, it became stronger. This process, known as work or strain hardening, is still used widely in metallurgy and manufacturing today to increase the strength of everything from car frames to overhead power wires. But materials scientists have never been able to watch this essential process unfold in real time—until now.

    A team of scientists  have observed, for the first time, the detailed mechanisms driving the fundamental process of work hardening.

    It's been impossible to observe work hardening in metals in real time because the atomic structures can only be observed through an electron microscope. Researchers can compare the structure before and after deformation but have had only a limited view into what happens during the process. Previous research has revealed that imperfections in the structure, known as dislocations, form a network of defects which cause the work hardening.

    Part 1

  • Dr. Krishna Kumari Challa

    To understand that critical part of the process, the research team turned to colloidal crystals—particles that are about 10,000 times larger than atoms and spontaneously form a crystal structure at high concentrations. These crystals are used to mimic atomic systems because they have the same structures, undergo the same phase transitions, and possess the same types of defects. Colloidal crystals, however, are very soft—even 100,000 times softer than Jell-O.

    The researchers grew these colloidal crystals composed of millions of particles and observed each particle using a confocal optical microscope. When they applied a strain to these crystals, they could measure the motion of each and every particle.

    Surprisingly, these colloidal crystals experience significant work hardening—even more strongly than any other material. In fact, when the difference in particle size is taken into account, these ultra-soft materials become much stronger than most metals.
    It is the first time that work hardening has been observed in colloidal crystals; it reveals that the process is governed primarily by the geometry of the particles and the defects. The crystals became stronger because of the dislocation defects, how they interact and entangle with one another.

    These observations reveal the universal mechanisms of work hardening which will also apply more generally to all materials.

    Seongsoo Kim et al, Work hardening in colloidal crystals, Nature (2024). DOI: 10.1038/s41586-024-07453-6

    Part 2

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  • Dr. Krishna Kumari Challa

    Global study shows that most cities receive more rainfall than surrounding rural areas

    The effect of urbanization on temperature is relatively well-known: cities are often measurably warmer than their surrounding rural areas. This is called the urban heat island effect. What fewer people know is that the urban heat island has a twin counterpart with similarly important consequences: the urban precipitation anomaly, where the presence of urban development measurably affects the amount of rainfall in an area.

    In a study published in Proceedings of the National Academy of Sciences, researchers looked for evidence of precipitation anomalies in 1,056 cities across the globe and found that more than 60% of those cities receive more precipitation than their surrounding rural areas.

    In some cases, the difference can be significant. For instance, researchers found that Houston, on average, will receive almost 5 inches more rain per year than its surrounding rural areas.

    This could have wide-ranging implications, the most serious of which is worsened flash flooding in densely built urban areas.

    Variation in urban rainfall is something scientists have known about for several decades, but never at a global scale. Previous studies only looked at certain cities and storm cases.

    Urban areas tend to take rain from one location and concentrate it in another, much like a sponge that is being squeezed. If you were to pinch one part of the sponge, you would have water coming down more forcefully from one side. The amount of water you have in the sponge is the same, but because now you have that dynamic sort of squeezing the atmosphere, you have more ability to take the water out from that location.

    Although it's less common, some urban areas actually receive less rainfall than their surrounding rural counterparts. This typically occurs in cities situated in valleys and lowlands, where precipitation patterns are controlled by nearby mountains. The cities where this is most pronounced include Seattle, Washington; Kyoto, Japan; and Jakarta, Indonesia.

    Part1

  • Dr. Krishna Kumari Challa

    There are several reasons why most cities receive more rainfall than their rural neighbors.
    One key factor is the presence of tall buildings, which block or slow down wind speeds. This leads to a convergence of air toward the city center.
    The buildings further enhance this convergence by slowing the winds, resulting in a stronger upward motion of air. This upward motion promotes the condensation of water vapor and cloud formation, which are critical conditions for producing rainfall and precipitation.
    Researchers found that population has the largest correlation with urban precipitation anomalies compared to other environmental and urbanization factors. This is because larger populations typically create denser and taller urban areas, along with more greenhouse gas emissions, and therefore more pronounced heat.
    This phenomenon has implications for all cities heading into a future of climate change.
    the increased chances of rainfall in cities combined with the impervious surfaces that make up their urban environments can be a recipe for flash flooding.

    Niyogi, Dev, Global scale assessment of urban precipitation anomalies, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2311496121doi.org/10.1073/pnas.2311496121

    Part2

  • Dr. Krishna Kumari Challa

    Iron was life's 'primeval' metal, say scientists

    Every living organism uses tiny quantities of metals to carry out biological functions, including breathing, transcribing DNA, turning food into energy, or any number of essential life processes.

    Life has used metals in this way since single-celled organisms floated in Earth's earliest oceans. Nearly half of the enzymes—proteins that carry out chemical reactions in cells—within organisms require metals, many of which are transition metals named for the space they occupy in the periodic table.

    Now, a team of scientists argue that iron was life's earliest, and sole, transition metal. Their study, titled "Iron: Life's primeval transition metal," is published in the Proceedings of the National Academy of Sciences.

    They argue that life only relied on metals that it could interact with, and the iron-rich early ocean would make other transition metals essentially invisible.

    Early oceans were rich in iron—specifically, an ion of iron called Fe(II). Fe(II) can be readily dissolved in water and would have been the primary metal found in oceans during the Archean Eon, a geologic time period that began about 4 billion years ago and ended about 2.5 billion years ago.

    The end of the Archean Eon was marked by something called the Great Oxygenation Event. At this time, life evolved the ability to perform oxygen-producing photosynthesis. Over the next billion years, Earth's ocean transformed from an iron-rich, anoxic sea to today's oxygenated body of water, according to the researchers. This also oxidized Fe(II) into Fe(III), rendering it insoluble.

    Geologists knew of iron's ubiquity on Earth during this time, it wasn't until they began talking with Valentine that they realized how great an impact iron might have had on early life.

    Life, in the face of orders of magnitude more iron than other metals, couldn't know to evolve toward such a sophisticated way of managing them. The fall of the abundance of iron forced life to manage these other metals to survive, but that also enabled new functions and the diversity of life we have today.

    Johnson, Jena E., Iron: Life's primeval transition metal, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2318692121doi.org/10.1073/pnas.2318692121

    **

  • Dr. Krishna Kumari Challa

    Plastic pollution hotspots pinpointed in new research—India ranks top due to high levels of uncollected waste

    Researchers have used machine learning to identify the biggest plastic pollution hotspots across more than 50,000 towns, cities and rural areas worldwide. Their new global model reveals the most detailed picture of plastic pollution ever created with the highest environmental concentrations in India, predominantly because so much of its waste isn't collected.

    Open burning of waste is prolific, accounting for 57% of all plastic pollution worldwide by weight. This involves burning waste on open fires without any controls to prevent hazardous emissions from reaching the environment or harming our health. This practice is popular, possibly because it seems to make the waste disappear, reducing the burden on waste management authorities and reducing the unsightliness of waste dumped on land.
    India has emerged as the largest plastic polluter, emitting 9.3 million tons of plastic into the environment each year—one fifth of the total. That's 2.7 times more than the next two largest polluters, Nigeria and Indonesia.

    India comes top because only 81% of its waste is collected. But, it also generates a lot more waste than some previous models have assumed. Official government sources estimate 0.12kg per person per day, but these estimates exclude many rural areas, so the real number is closer to 0.54kg per person per day. The combination of such a large amount of waste, large population and low collection rate creates the conditions under which plastic pollution flourishes.

    https://www.nature.com/articles/s41586-024-07758-6

  • Dr. Krishna Kumari Challa

    The Calls of Amazon Parrots are changing!

    Some parrots in the Amazon no longer sound like they used to when they call out to each other through the trees.

    Scientists studying the yellow-naped amazon (Amazona auropalliata) have noticed in the last few decades that these Pacific coast parrots are changing their 'accents'. While it could interfere with mating and reproduction, the researchers speculate it might actually be a positive sign of the birds adapting.

    Like many other birds, yellow-naped parrots are known to have regional dialects. This means that different communities shriek, whistle, and screech in slightly different ways, depending on where they live.

    Scientists have noticed this about the species since 1994, but between 2005 and 2016, researchers from New Mexico State University and the University of Pittsburgh (UPJ) at Johnstown have noticed a significant geographic shift.

    The types of calls these parrots are making in different regions seem to be bleeding into one another.

    Some calls that were recently heard in the north region, for instance, had only previously been heard in the south. In fact, some birds in the north were capable of producing both accents, researchers found, what they call a 'bilingual' skill.

    This could possibly give the parrots a survival advantage. Birds that can communicate with more groups may be able to share more information, access foraging areas, or gain roosting privileges.

    And that may be more important now than ever.

    https://royalsocietypublishing.org/doi/10.1098/rspb.2024.0659