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 researchers suggest that a drug used to treat ulcerative colitis, Crohn's disease and other inflammatory bowel diseases, mesalazine (5-aminosalicylate), may be a treatment for sorbitol intolerance in humans. Mesalazine, also known as mesalamine, functions similarly to the butyrate-producing bacteria, restoring the low oxygen levels in the intestine preferred by Clostridia.

     High fat intake sustains sorbitol intolerance after antibiotic-mediated Clostridia depletion from the gut microbiota, Cell (2024). DOI: 10.1016/j.cell.2024.01.029www.cell.com/cell/fulltext/S0092-8674(24)00066-7

    Part 2

  • Dr. Krishna Kumari Challa

    Researchers discover that a rare fat molecule helps drive cell death

    Researchers have found that a rare type of lipid is a key driver of ferroptosis, a form of cell death discovered by  professor Brent Stockwell.

    Stockwell first discovered ferroptosis in 2012, when he found that certain cells were dying because their lipid layers were collapsing—an unusual form of  cell death that differs from the most common kind, which begins with the cell forming blisters on its outer surface.

    Since that discovery, researchers in Stockwell's lab and elsewhere have continued to investigate ferroptosis, discovering that it can occur naturally in aging cells, in pathological contexts, and can be induced to treat disease.

    The findings, appearing in Cell, provide new detail on how cells die during ferroptosis and could improve understanding of how to stop ferroptosis in contexts where it is harmfully occurring—in neurodegenerative diseases, for example—or induce it in contexts where it could be useful, such as using it to kill dangerous cancer cells.

    The new research found that a rare type of lipid with two polyunsaturated fatty acyl tails, called a diPUFA phospholipid, was present in a range of contexts where ferroptosis was occurring, including in aging brains and Huntington disease-affected brain tissue. The finding indicates that the lipid is efficient at promoting ferroptosis.

    Another paper out in February 2024 with several co-authors found that a gene named PHLDA2 can sometimes promote ferroptosis by attacking a different lipid, and that this gene can block some tumors from forming. Together, these papers show that specific lipids promote ferroptosis, so defining the driver lipids in specific cancers is important.

    The discovery that these diPUFA lipids are important drivers of ferroptosis deepens our understanding of this form of cell death, and these lipids' role in controlling a cell's homeostasis in general.

    Harnessing these lipids may eventually help us identify where ferroptosis has occurred and deliberately manipulate them to either induce cell death or stop it. This can begin to give us both understanding and the power to control cell death.

    Phospholipids with two polyunsaturated fatty acyl tails promote ferroptosis, Cell (2024). DOI: 10.1016/j.cell.2024.01.030www.cell.com/cell/fulltext/S0092-8674(24)00067-9

  • Dr. Krishna Kumari Challa

    Ancient retroviruses played a key role in the evolution of vertebrate brains, suggest researchers

    Researchers report in the journal Cell that ancient viruses may be to thank for myelin—and, by extension, our large, complex brains.

    The team found that a retrovirus-derived genetic element or "retrotransposon" is essential for myelin production in mammals, amphibians, and fish. The gene sequence, which they dubbed "RetroMyelin," is likely a result of ancient viral infection, and comparisons of RetroMyelin in mammals, amphibians, and fish suggest that retroviral infection and genome-invasion events occurred separately in each of these groups.

    Retroviruses were required for vertebrate evolution to take off. If we didn't have retroviruses sticking their sequences into the vertebrate genome, then myelination wouldn't have happened, and without myelination, the whole diversity of vertebrates as we know it would never have happened.

    Myelin is a complex, fatty tissue that ensheathes vertebrate nerve axons. It enables rapid impulse conduction without needing to increase axonal diameter, which means nerves can be packed closer together. It also provides metabolic support to nerves, which means nerves can be longer.
    Myelin first appeared in the tree of life around the same time as jaws, and its importance in vertebrate evolution has long been recognized, but until now, it was unclear what molecular mechanisms triggered its appearance.
    The researchers noticed RetroMyelin's role in myelin production when they were examining the gene networks utilized by oligodendrocytes, the cells that produce myelin in the central nervous system.

    A retroviral link to vertebrate myelination through retrotransposon RNA-mediated control of myelin gene expression, Cell (2024). DOI: 10.1016/j.cell.2024.01.011www.cell.com/cell/fulltext/S0092-8674(24)00013-8

  • Dr. Krishna Kumari Challa

    Scientists report first look at electrons moving in real-time in liquid water

    In an experiment akin to stop-motion photography, scientists have isolated the energetic movement of an electron while "freezing" the motion of the much larger atom it orbits in a sample of liquid water.

    The findings, reported in the journal Science, provide a new window into the electronic structure of molecules in the liquid phase on a timescale previously unattainable with X-rays. The new technique reveals the immediate electronic response when a target is hit with an X-ray, an important step in understanding the effects of radiation exposure on objects and people.

     Shuai Li et al, Attosecond-pump attosecond-probe x-ray spectroscopy of liquid water, Science (2024). DOI: 10.1126/science.adn6059www.science.org/doi/10.1126/science.adn6059

  • Dr. Krishna Kumari Challa

    How do oceans start to close? New study suggests the Atlantic may 'soon' enter its declining phase

    A new study, resorting to computational models, predicts that a subduction zone currently below the Gibraltar Strait will propagate further inside the Atlantic and contribute to forming an Atlantic subduction system—an Atlantic ring of fire. This will happen 'soon' in geological terms—in approximately 20 million years.

    Oceans seem eternal to our lifespan, but they are not here for long: they are born, grow, and one day close. This process, which takes a few hundred million years, is called Wilson Cycle. The Atlantic, for example, was born when Pangea broke up around 180 million years ago and will one day close. And the Mediterranean is what remains from a big ocean—the Tethys– that once existed between Africa and Eurasia.

    For an ocean like the Atlantic to stop growing and start closing, new subduction zones—places where one tectonic plate sinks below another—have to form. But subduction zones are hard to form, as they require plates to break and bend, and plates are very strong. A way out of this "paradox" is to consider that subduction zones can migrate from a dying ocean in which they already exist—the Mediterranean—into pristine oceans—such as the Atlantic. This process was dubbed subduction invasion.

    This study shows for the first time how such a direct invasion can happen. The computational, gravity-driven 3D model predicts that a subduction zone currently below the Gibraltar Strait will propagate further inside the Atlantic and contribute to forming an Atlantic subduction system—an Atlantic ring of fire, in an analogy to the already existing structure in the Pacific. This will happen 'soon' in geological terms—but not before approximately 20 million years.

    João C. Duarte et al, Gibraltar subduction zone is invading the Atlantic, Geology (2024). DOI: 10.1130/G51654.1

  • Dr. Krishna Kumari Challa

    New study finds little-known toxic crop chemical in four out of five people tested

    A new Environmental Working Group study has found chlormequat, a little-known pesticide, in four out of five people tested. Because the chemical is linked to reproductive and developmental problems in animal studies, the findings suggest the potential for similar harm to humans.

    EWG's research, published February 15 in the Journal of Exposure Science and Environmental Epidemiology, tested the urine of 96 people for the presence of chlormequat, finding it in 77 of them.

    The ubiquity of this little-studied pesticide in people raises alarm bells about how it could potentially cause harm without anyone even knowing they've consumed it.

    Environmental Protection Agency regulations allow the chemical to be used on ornamental plants only—not food crops. But now some governments have made concessions that have resulted in these alarming consequences!

     A pilot study of chlormequat in food and urine from adults in the United States from 2017 to 2023, Journal of Exposure Science & Environmental Epidemiology (2024). DOI: 10.1038/s41370-024-00643-4

  • Dr. Krishna Kumari Challa

    Why Is It So Hard to Swat a Fly?

  • Dr. Krishna Kumari Challa

    Earth Receives First Beams of Solar Power From Space!

    For the first time ever, Earth has received a tangible zap of solar energy beamed directly from space, marking a historic moment in our quest for clean, limitless power thanks to the Space Solar Power Demonstrator (SSPD).

    SSPD's MAPLE experiment has used a satellite called DOLCE and beamed 100 milliwatts of power from space, with 1 milliwatt reaching Earth — a small but mighty first step.

    Unlike here on Earth, solar energy in space is unencumbered by factors like day and night, or obstruction by clouds and weather on our planet. This makes space-based solar harvesters ideal as they could potentially yield roughly eight times more power than even the most efficient solar panels on the Earth’s surface.

    https://www.space.com/space-solar-power-satellite-beams-energy-1st-...

  • Dr. Krishna Kumari Challa

    The microbes, discovered by researchers deep inside SURF, could help reduce carbon emissions.
    At room temperature, carbon dioxide, or CO2, is a gas, which makes it hard to store for long periods of time. One idea to reduce carbon emissions involves pumping this greenhouse gas underground into deep caverns or rock layers in a process called geologic sequestration.
    When injected as a gas, CO2 has the potential to leak back to the atmosphere. For example, if a geologic fault occurs or when there are changes in pressure following the initial pumping on the surface, stored gas will be looking for a way to escape.

    To solve this problem, scientists are exploring efforts to bind CO2 gas underground by pumping it into rock layers with specific geochemical properties that will dissolve the gas and turn it into a carbonate mineral in a process called in-situ mineralization. However, this process takes a long time, between 7 to 10 years, in nature. But an innovation discovered by researchers working at the Sanford Underground Research Facility (SURF) could change this.

    The team of researchers found a set of naturally occurring microbes inside SURF that eat carbon dioxide gas and turn it into solid rock through a process called carbon mineralization. 

    Part 1

  • Dr. Krishna Kumari Challa

    These microbes, or extremophiles, were found inside SURF located in the former Black Hills mining town of Lead, SD. The team has spent years hunting for these extremophiles that grow thousands of feet below ground inside water-filled rock fractures with unique properties that enable them to thrive in extreme environments.

    Researchers were able to isolate four types of microbes found at SURF and show, through a series of laboratory experiments, that they can turn large quantities of carbon dioxide into rocks that will remain stable and out of atmospheric circulation for thousands of years. 

    The findings may lead to new ways to permanently capture CO2 emissions, reducing the impacts of climate change.

    The team has presented this research at multiple scientific conferences in the United States and Europe, including the Dec. 2023 meeting of the American Geophysical Union in Chicago and the July 2023, Goldschmidt Conference in Lyon, France.

    https://sanfordlab.org/article/university-researchers-discover-micr...

    Part 2

  • Dr. Krishna Kumari Challa

    New theory for gravastars

    The interior of black holes remains a conundrum for science. In 1916, German physicist Karl Schwarzschild outlined a solution to Albert Einstein's equations of general relativity, in which the center of a black hole consists of a so-called singularity, a point at which space and time no longer exist. Here, the theory goes, all physical laws, including Einstein's general theory of relativity, no longer apply; the principle of causality is suspended.

    This constitutes a great nuisance for science—after all, it means that no information can escape from a black hole beyond the so-called event horizon. This could be a reason why Schwarzschild's solution did not attract much attention outside the theoretical realm—that is, until the first candidate for a black hole was discovered in 1971, followed by the discovery of the black hole in the center of our Milky Way in the 2000s, and finally the first image of a black hole, captured by the Event Horizon Telescope Collaboration in 2019.

    In 2001, Pawel Mazur and Emil Mottola proposed a different solution to Einstein's field equations that led to objects that they called gravitational condensate stars, or gravastars. Contrary to black holes, gravastars have several advantages from a theoretical astrophysics perspective.

    On the one hand, they are almost as compact as black holes and also exhibit a gravity at their surface that is essentially as strong as that of a black hole, hence resembling a black hole for all practical purposes. On the other hand, gravastars do not have an event horizon, that is, a boundary from within which no information can be sent out, and their core does not contain a singularity.

    Instead, the center of a gravastar is made up of an exotic (dark) energy that exerts a negative pressure to the enormous gravitational force compressing the star. The surface of a gravastar is represented by a wafer-thin skin of ordinary matter, the thickness of which approaches zero.

    Theoretical physicists Daniel Jampolski and Prof. Luciano Rezzolla of Goethe University Frankfurt have now presented a solution to the field equations of general realtivity that describes the existence of a gravastar inside another gravastar. They have given this hypothetical celestial object the name "nestar" (from the English "nested"). The study is published in Classical and Quantum Gravity.

    The nestar is like a matryoshka doll. The solution to the field equations allows for a whole series of nested gravastars. It's a little easier to imagine that something like this could exist.

    It's great that even 100 years after Schwarzschild presented his first solution to Einstein's field equations from the general theory of relativity, it's still possible to find new solutions. It's a bit like finding a gold coin along a path that has been explored by many others before. Unfortunately, we still have no idea how such a gravastar could be created. But even if nestars don't exist, exploring the mathematical properties of these solutions ultimately helps us to better understand black holes.

     Daniel Jampolski et al, Nested solutions of gravitational condensate stars, Classical and Quantum Gravity (2024). DOI: 10.1088/1361-6382/ad2317

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  • Dr. Krishna Kumari Challa

  • Dr. Krishna Kumari Challa

    New study on decomposing microbes could help transform forensic science

    For the first time, researchers have identified what appears to be a network of approximately 20 microbes that universally drive the decomposition of animal flesh. The findings have significant implications for the future of forensic science, including the potential to provide crime scene investigators with a more precise way to determine a body's time of death.

    Decomposition of dead biological material is one of Earth's most fundamental processes. Organic plant waste accounts for the vast majority of matter that is decomposed, a process that is relatively well understood. Comparatively little, however, is known about the ecology of vertebrate decomposition, including humans, and better understanding how humans decompose has the potential to advance forensic science.

    This new study, a multi-year undertaking, involved decomposing 36 cadavers at three different forensic anthropological facilities.

    The bodies were decomposed in different climates and during all four seasons. The research team then collected skin and soil samples during the first 21 days for each decomposing body.

    Researchers generated a significant amount of molecular and genomic information from the samples. They then used that information to construct an overall picture of the "microbial community," or microbiome, present at each site. They are also collected other details like what microbes are there, how did they get there, how does that change over time and what are they doing.

    Regardless of climate or soil type, researchers found the same set of approximately 20 specialist decomposing microbes on all 36 bodies. What's more, those microbes arrived like clockwork at certain points throughout the 21-day observation period, and insects played a key role in their arrival.

    They saw similar microbes arrive at similar times during decomposition, regardless of any number of outdoor variables you can think of.

    Identifying the decomposing microbiome's consistent makeup and timing has important implications for forensic science. So researchers built a tool that can accurately predict a body's time since death, also known as the postmortem interval.

     Jessica Metcalf, A conserved interdomain microbial network underpins cadaver decomposition despite environmental variables, Nature Microbiology (2024). DOI: 10.1038/s41564-023-01580-ywww.nature.com/articles/s41564-023-01580-y

  • Dr. Krishna Kumari Challa

    Don’t let ‘FDA-approved’ or ‘patented’ in ads give you a false sense of security

    "FDA approved"  means a product's benefits have been found to outweigh its risks for a specific purpose – not that it's of high quality or low risk in general.

    But  advertisers throw these terms around in confusing ways.
    Researchers, for instance, found an ad for a probiotic supplement stating, "The proof is in the patent"; an ad for an earwax removal product stating its "patented formula is safe, effective, and clinically proven"; and an ad for a headache remedy that made the words "FDA approved" a bold visual focal point.
    And these terms appear most often in ads for things you eat or rub onto your skin, such as supplements, insecticides, toothpaste and lotions. That's probably no coincidence. Products like this aren't tightly regulated, yet consumers want to know they're safe. It seems likely that advertisers are name-dropping the government to make people think just that.

    One danger is clear: Ads with vague references to government authorities could dupe consumers into thinking products are safer or more effective than they actually are. In fact, there's some evidence this is already happening.

    Another risk is that this creates perverse incentives for business. Companies could chose to forgo actual innovation, focusing instead on securing dubious patents or regulatory nods to keep up in the advertising race.

    These practices could distort competition, burden government agencies with frivolous patent applications and deter new entrants from competing in markets where they can't employ similar advertising tactics.

  • Dr. Krishna Kumari Challa

    Study discovers link between high levels of niacin and heart disease

    Clinic researchers have identified a new pathway that contributes to cardiovascular disease associated with high levels of niacin, a common B vitamin previously recommended to lower cholesterol.

    The researchers discovered a link between 4PY, a breakdown product from excess niacin, and heart disease. Higher circulating levels of 4PY were strongly associated with development of heart attack, stroke and other adverse cardiac events in large-scale clinical studies. The researchers also showed in preclinical studies that 4PY directly triggers vascular inflammation which damages blood vessels and can lead to atherosclerosis over time.

    The study, published in Nature Medicine, also details genetic links between 4PY and vascular inflammation. The findings provide a foundation for potential new interventions and therapeutics to reduce or prevent that inflammation.

    What's exciting about these results is that this pathway appears to be a previously unrecognized yet significant contributor to the development of cardiovascular disease. What's more, we can measure it, meaning there is potential for diagnostic testing. These insights set the stage for developing new approaches to counteract the effects of this pathway.

     Stanley Hazen, A terminal metabolite of niacin promotes vascular inflammation and contributes to cardiovascular disease risk, Nature Medicine (2024). DOI: 10.1038/s41591-023-02793-8www.nature.com/articles/s41591-023-02793-8

  • Dr. Krishna Kumari Challa

    The antibiotic that evades bacterial resistance

    Scientists have developed an antibiotic that could give medicine a new weapon to fight drug-resistant bacteria and the diseases they cause.

    The antibiotic, cresomycin, described in Science, effectively suppresses pathogenic bacteria that have become resistant to many commonly prescribed antimicrobial drugs.

    In developing the new antibiotic, the researchers focused on how many antibiotics interact with a common cellular target—the ribosome—and how drug-resistant bacteria modify their ribosomes to defend themselves.

    More than half of all antibiotics inhibit growth of pathogenic bacteria by interfering with their protein biosynthesis—a complex process catalyzed by the ribosome, which is akin to a 3D printer that makes all the proteins in a cell. Antibiotics bind to bacterial ribosomes and disrupt this protein-manufacturing process, causing bacterial invaders to die.

    But many bacterial species evolved simple defenses against this attack. In one defense, they interfere with antibiotic activity by adding a single methyl group of one carbon and three hydrogen atoms to their ribosomes. Scientists speculated that this defense was simply bacteria physically blocking the site where drugs bind to the ribosome, like putting a push pin on a chair.

    But the researchers found a more complicated story, as they described in a paper published last month in Nature Chemical Biology.

    By using a method called X-ray crystallography to visualize drug-resistant ribosomes with nearly atomic precision, they discovered two defensive tactics. The methyl group, they found, physically blocks the binding site, but it also changes the shape of the ribosome's inner "guts," further disrupting antibiotic activity.

    Part 1

  • Dr. Krishna Kumari Challa

    They then used X-ray crystallography to investigate how certain drugs, including one published in Nature by the UIC/Harvard collaboration in 2021, circumvent this common form of bacterial resistance.

    By determining the actual structure of antibiotics interacting with two types of drug-resistant ribosomes, the researchers saw what could not have been predicted by the available structural data or by computer modeling.

    Cresomycin, the new antibiotic, is synthetic. It's preorganized to avoid the methyl-group interference and attach strongly to ribosomes, disrupting their function. This process involves locking the drug into a shape that is pre-optimized to bind to the ribosome, which helps it get around bacterial defenses.

    It simply binds to the ribosomes and acts as if it doesn't care whether there was this methylation or not. It overcomes several of the most common types of drug resistance easily.

    In animal experiments conducted at Harvard, the drug protected against infections with multidrug-resistant strains of common disease drivers including Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Based on these promising results, the next step is to assess the effectiveness and safety of cresomycin in humans.

    But even at this early stage, the process demonstrates the critical role that structural biology plays in designing the next generation of antibiotics and other life-saving medicines.

    Elena V. Aleksandrova et al, Structural basis of Cfr-mediated antimicrobial resistance and mechanisms to evade it, Nature Chemical Biology (2024). DOI: 10.1038/s41589-023-01525-w

    Part 2

  • Dr. Krishna Kumari Challa

    Some Babies Are Born With Twisted Insides: here is the reason

    Scientists have identified a possible cause for intestinal malrotation; a common but poorly understood condition present at birth in which the gut doesn't rotate properly during development.

    Researchers found that exposure to the herbicide atrazine can disrupt gut rotation development in frog embryos, whose guts develop similarly to humans.

    Because frog embryos develop in only a few days and are highly experimentally accessible, they allow us to quickly test new hypotheses about how and why development goes awry during malrotation.

    During the development of the digestive system, the gut tube of vertebrates grows a lot longer. This extra length fits inside the body's relatively small space because of a process called intestinal rotation, that winds the 'tube' tightly into a compact coil.
    In humans this rotation is thought to result from a revolution in the embryonic intestinal tract, though the precise mechanism remains unknown.
    As vertebrates, frogs and humans share a common ancestor and have many similar anatomical features, including an intestine that rotates in a counter-clockwise direction.
    part 1
  • Dr. Krishna Kumari Challa

    The rotation process fails in about 1 in 500 human births, resulting in a displacement of the bowel known as intestinal malrotation. This malrotation can lead to severe complications, such as bowel obstructions from the intestine looping around itself, requiring surgery in early infancy.
    Researchers zeroed in on atrazine as a potential cause after it had been discovered that the herbicide dramatically increased the frequency of intestinal rotation in the wrong direction in lab experiments on frogs.
    Atrazine is one of the most widely used agricultural herbicides in several countries, although it is banned in some now.

    Exposure to atrazine under laboratory conditions caused a metabolic imbalance in frog embryos that prevented cells from properly dividing, growing, or rearranging themselves, which disrupted several cellular processes in the gut. It became harder for the tissues to stretch normally, which made the gut tube shorter.

    "The resultant decreased length of the gut tube consequently prevents the crucial hairpin loop of the intestine from achieving its normal anatomical position, compelling the intestine to coil in a reversed orientation," the study authors write.

    According to the team, these gut development issues seem to stem from the fact that atrazine throws the body's redox reactions off balance. Imbalances between a cell's oxidants and antioxidants can play a role in diseases. Treating the frogs with antioxidants before they were exposed to atrazine prevented their guts from twisting the wrong way.

    It's important to note that the frog embryos were exposed to 1,000 times the levels normally found in the environment, and these results don't prove that exposure to atrazine causes malrotation in humans.

    That said, the findings emphasize the importance of metabolic pathways in gut development and highlight possible causes of intestinal malrotation, though there's a lot more to learn.

    https://journals.biologists.com/dev/article/151/4/dev202020/343079/...

    Part 2

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  • Dr. Krishna Kumari Challa

    Magnetic effects at the origin of life? It's the spin that makes the difference

    Biomolecules such as amino acids and sugars occur in two mirror-image forms—in all living organisms, however, only one is ever found. Why this is the case is still unclear. Researchers  have now found evidence that the interplay between electric and magnetic fields could be at the origin of this phenomenon.

    The so-called homochirality of life—the fact that all biomolecules in living organisms only ever occur in one of two mirror-image forms—has puzzled a number of scientific luminaries, from the discoverer of molecular chirality, Louis Pasteur, to William Thomson (Lord Kelvin) and Nobel Prize winner Pierre Curie. A conclusive explanation is still lacking, as both forms have, for instance, the same chemical stability and do not differ from each other in their physicochemical properties. The hypothesis, however, that the interplay between electric and magnetic fields could explain the preference for one or the other mirror-image form of a molecule—so-called enantiomers—emerged early on.

    It was only a few years ago, though, that the first indirect evidence emerged that the various combinations of these force fields can indeed "distinguish" between the two mirror images of a molecule. This was achieved by studying the interaction of chiral molecules with metallic surfaces that exhibit a strong electric field over short distances.
    The surfaces of magnetic metals such as iron, cobalt or nickel thus allow electric and magnetic fields to be combined in various ways—the direction of magnetization is simply reversed, from "North up—South down" to "South up—North down."

    If the interplay between magnetism and electric fields actually triggers "enantioselective" effects, then the strength of the interaction between chiral molecules and magnetic surfaces should also differ, for example—depending on whether a right-handed or left-handed molecule "settles" on the surface.
    Part 1
  • Dr. Krishna Kumari Challa

    Mirror images prefer opposing magnetic fields: And this is indeed the case, as a team of researchers reported in the journal Advanced Materials.

    --

    The team coated a (non-magnetic) copper surface with small, ultra-thin "islands" of magnetic cobalt and determined the direction of the magnetic field in these using spin-polarized scanning tunneling microscopy; as mentioned before, this can run in two different directions perpendicular to the metal surface: North up or South up. They then deposited spiral-shaped chiral molecules—a 1:1 mixture of left- and right-handed heptahelicene molecules—onto these cobalt islands in ultrahigh vacuum.

    Then they "simply" counted the number of right- and left-handed helicene molecules on the differently magnetized cobalt islands, almost 800 molecules in total, again using scanning tunneling microscopy. And lo and behold: Depending on the direction of magnetic field, one or the other form of the helicene spirals had settled preferentially.

    Moreover, the experiments showed that the selection—the preference for one or the other enantiomer—not only occurs during the binding on the cobalt islands, but already beforehand.

    Before the molecules take up their final (preferred) position on one of the cobalt islands, they migrate long distances across the copper surface in a significantly weaker bound precursor state in "search" for an ideal position. They are only bound to the surface by so-called van der Waals forces. These are merely caused by fluctuations in the electronic shell of atoms and molecules and are therefore relatively weak. The fact that even these are influenced by magnetism, i.e. the direction of rotation (spin) of the electrons, was not known thus far.

    Part 2

  • Dr. Krishna Kumari Challa

    Electrons with the 'wrong' spin are filtered out
    Using scanning tunneling microscopy, the researchers were also able to solve another mystery, as they reported in the journal Small in November 2023. Electron transport—i.e. electric current—also depends on the combination of molecular handedness and magnetization of the surface.

    Depending on the handedness of the bound molecule, electrons with one direction of spin preferentially flow—or "tunnel"—through the molecule, meaning that electrons with the "wrong" spin are filtered out. This chirality-induced spin selectivity had already been observed in earlier studies, but it remained unclear whether an ensemble of molecules is necessary for this or whether individual molecules also exhibit this effect.
    The researchers think that these findings eventually cannot fully answer the question of the chirality of life.
    However, they can imagine that in certain surface-catalyzed chemical reactions—such as those that could have taken place in the chemical "primordial soup" on the early Earth—a certain combination of electric and magnetic fields could have led to a steady accumulation of one form or another of the various biomolecules—and thus ultimately to the handedness of life.

    Mohammad Reza Safari et al, Enantioselective Adsorption on Magnetic Surfaces, Advanced Materials (2023). DOI: 10.1002/adma.202308666

    Part 3

  • Dr. Krishna Kumari Challa

    Decimal point is older than thought
    The decimal point was invented by Italian merchant and astronomer Giovanni Bianchini some 150 years before what was considered to be its first appearance. “I remember running up and down the hallways of the dorm with my computer trying to find anybody who was awake, shouting ‘look at this, this guy is doing decimal points in the 1440s!’” recalls historian Glen Van Brummelen, who discovered Bianchini’s number “with a dot in the middle” while teaching at a maths camp for kids. Bianchini’s training in economics might have given him a perspective different to that of his astronomer peers — who would have exclusively been using the sexagesimal (base 60) system — and his approach was perhaps too revolutionary to catch on until much later.

    https://www.nature.com/articles/d41586-024-00473-2?utm_source=Live+...

    https://www.sciencedirect.com/science/article/pii/S0315086024000016...

  • Dr. Krishna Kumari Challa

    Neanderthals' usage of complex adhesives reveals higher cognitive abilities, scientists discover

    Neanderthals created stone tools held together by a multi-component adhesive, a team of scientists has discovered. Its findings, which are the earliest evidence of a complex adhesive in Europe, suggest these predecessors to modern humans had a higher level of cognition and cultural development than previously thought.

    These astonishingly well-preserved tools showcase a technical solution broadly similar to examples of tools made by early modern humans in Africa, but the exact recipe reflects a Neanderthal 'spin,' which is the production of grips for handheld tools.

    The researchers discovered traces of a mixture of ocher and bitumen on several stone tools, such as scrapers, flakes, and blades. Ocher is a naturally occurring earth pigment; bitumen is a component of asphalt and can be produced from crude oil, but also occurs naturally in the soil.

    Overall, the development of adhesives and their use in the manufacture of tools is considered to be some of the best material evidence of the cultural evolution and cognitive abilities of early humans. Compound adhesives are considered to be among the first expressions of the modern cognitive processes that are still active today.

     Patrick Schmidt, Ochre-based compound adhesives at the Mousterian type-site document complex cognition and high investment, Science Advances (2024). DOI: 10.1126/sciadv.adl0822www.science.org/doi/10.1126/sciadv.adl0822

  • Dr. Krishna Kumari Challa

    Electrons become fractions of themselves in graphene, study finds

    The electron is the basic unit of electricity, as it carries a single negative charge. This is what we're taught in high school physics, and it is overwhelmingly the case in most materials in nature.

    But in very special states of matter, electrons can splinter into fractions of their whole. This phenomenon, known as "fractional charge," is exceedingly rare, and if it can be corralled and controlled, the exotic electronic state could help to build resilient, fault-tolerant quantum computers.

    To date, this effect, known to physicists as the "fractional quantum Hall effect," has been observed a handful of times, and mostly under very high, carefully maintained magnetic fields. Only recently have scientists seen the effect in a material that did not require such powerful magnetic manipulation.

    Now, physicists have observed the elusive fractional charge effect, this time in a simpler material: five layers of graphene—an atom-thin layer of carbon that stems from graphite and common pencil lead. They report their results in Nature.

    The fractional quantum Hall effect is an example of the weird phenomena that can arise when particles shift from behaving as individual units to acting together as a whole. This collective "correlated" behavior emerges in special states, for instance when electrons are slowed from their normally frenetic pace to a crawl that enables the particles to sense each other and interact. These interactions can produce rare electronic states, such as the seemingly unorthodox splitting of an electron's charge.

    Researchers found that when five sheets of graphene are stacked like steps on a staircase, the resulting structure inherently provides just the right conditions for electrons to pass through as fractions of their total charge, with no need for any external magnetic field.

    The results are the first evidence of the "fractional quantum anomalous Hall effect" (the term "anomalous" refers to the absence of a magnetic field) in crystalline graphene, a material that physicists did not expect to exhibit this effect.

     Long Ju, Fractional quantum anomalous Hall effect in multilayer graphene, Nature (2024). DOI: 10.1038/s41586-023-07010-7www.nature.com/articles/s41586-023-07010-7

  • Dr. Krishna Kumari Challa

    Scientists invent ultra-thin, minimally-invasive pacemaker controlled by light

    Millions of people around the world rely on pacemakers—small devices that regulate the electrical impulses of the heart in order to keep it beating smoothly. But to reduce complications, researchers would like to make these devices even smaller and less intrusive.

    A team of researchers  has developed a wireless device, powered by light, that can be implanted to regulate cardiovascular or neural activity in the body. The featherlight membranes, thinner than human hair, can be inserted with minimally invasive surgery and contain no moving parts.

    Published Feb. 21 in Nature, the results could help reduce complications in heart surgery and offer new horizons for future devices.

    Bozhi Tian, Monolithic silicon for high-spatiotemporal translational photostimulation, Nature (2024). DOI: 10.1038/s41586-024-07016-9www.nature.com/articles/s41586-024-07016-9

  • Dr. Krishna Kumari Challa

    Button batteries pose 'deadly' risk to toddlers

  • Dr. Krishna Kumari Challa

    How Did an Aquarium Stingray Get Pregnant without a Mate?

    Charlotte, a stingray at a North Carolina aquarium is pregnant—without a male stingray in her tank to impregnate her. Speculation is running wild that cohabitating sharks may be Charlotte’s mate. Here’s why that’s unlikely—and how the spontaneous pregnancy known as parthenogenesis is much, much cooler.

  • Dr. Krishna Kumari Challa

    The Global Importance of Tipping Points in Antarctica

    This video summarises the latest science on tipping points in Antarctica, as discovered by the research from the EU project TiPACCs. Listen to our scientists explaining the importance of studying the Antarctic Ice Sheet and surrounding ocean, the latest knowledge on changes in the continental shelf seas around Antarctica, whether the Antarctic Ice Sheet has already crossed a tipping point, what will happen when this tipping point is crossed, and what the latest developments are in coupled ocean - ice sheet modelling. Background: The Antarctic Ice Sheet covers about 98% of the Antarctic continent and is the largest single mass of ice on Earth. If the entire ice sheet were to disappear, this would cause sea levels globally to rise by nearly 60 meters on average. Ice loss from Antarctica has been increasing over the recent decades, and small changes in ocean conditions in the future could lead to long-lasting or even irreversible changes – with important implications for global sea-level rise.

  • Dr. Krishna Kumari Challa

    First Ever Drug For Frostbite

    Frostbite can occur at temperatures just below freezing (-0.55°C or 31.01°F), though at such temperatures frostbite is typically mild and no permanent damage will result.
    But what happens if you live and work somewhere where it gets much colder?
    Until now, there have been no approved therapies for severe frostbite. But on February 14 2024, the US Food and Drug Administration (FDA) announced that it had approved the very first drug to treat frostbite.

    Frostbite is evolution's response to prolonged or extreme cold, causing blood vessels to constrict and blood flow to slow in the extremities. This keeps blood flowing in the vital organs warm, increasing the chance of surviving in the extreme cold.
    The downside is this can result in permanent damage to the fingers, toes and parts of the face, sometimes requiring amputation of the affected body parts.
    The new drug, called iloprost (brand name Aurlumyn), is repurposed. This means that it was not originally developed to treat frostbite. In this case, it is used to treat high blood pressure within the lungs.
    Part 1
  • Dr. Krishna Kumari Challa

    Repurposed drugs have already passed important (and expensive) human safety testing and are therefore much cheaper (about US$40-80 million or £32-64 million) to develop for additional medical issues versus creating a new drug (about US$1-2 billion), making drug repurposing an attractive way to find new treatments.

    Many drugs have been tried as potential treatments for severe frostbite. However, iloprost is the first to be put through a clinical trial where patients with severe frostbite were randomly allocated to receive iloprost or not.

    The study found that 60 percent of the patients who did not receive iloprost had injuries sufficiently severe to warrant amputation, versus 0 percent of the patients who received iloprost.
    While the total number of patients tested in this study was small at 47, the combined facts that there are no other approved pharmaceutical treatments for frostbite and the impressive digit-saving results found in this randomised human trial were sufficient to convince the FDA to approve this repurposed therapy for severe frostbite.
    Iloprost works by expanding the blood vessels (called a vasodilator) of patients and stopping blood clots from forming. As frostbite causes constriction of blood vessels, this suggests one mechanism through which iloprost helps heal frostbitten tissue is by reversing this constriction.
    However, whenever blood flow is reintroduced in such tissue, it can paradoxically worsen the injury and cause more damage. This is called "reperfusion injury" and is largely caused by a sudden influx of oxygen causing oxidative stress.

    Interestingly, iloprost is not only a vasodilator but also reduces oxidative stress, suggesting this dual mechanism of action could help explain its impressive potential as a frostbite treatment.

    https://www.fda.gov/news-events/press-announcements/fda-approves-fi...

    https://theconversation.com/a-drug-to-treat-frostbite-is-finally-av...

  • Dr. Krishna Kumari Challa

    What is a Viral Vector Vaccine?

    Vaccines have revolutionized modern medicine by helping a person's immune system prevent diseases. There are many kinds of vaccines that have different benefits based on how they are made. A Viral Vector vaccine is a new, revolutionary type of vaccine the uses RNA in a shell made of... Viruses??

    What is mRNA, and how does it work?

  • Dr. Krishna Kumari Challa

    A type of cyberattack that could set your smartphone on fire using its wireless charger

    A team of security experts at the University of Florida working with security audit company CertiK has found that a certain class of cyberattacks could cause a smartphone to catch fire via its wireless charger. The team has posted a paper describing their research and results on the arXiv preprint server.

    Inductive chargers are devices that can be used to charge a smartphone or other device without the need for plugging in a cable. Such devices work by making use of electromagnetic fields to transfer energy from one device to another through induction. In order for a smartphone to be charged properly on such a device, it must communicate with the charger through a Qi communication-based feedback control system. And in order for a wireless charger to work, it must be connected to an AC outlet.
    But the charger, like a phone, cannot plug directly into the wall; it plugs instead into an adapter. And this, the researchers suggest, is where the system's vulnerabilities lie. They have found through testing that by attaching an intermediary device to the adapter, disruptions can be made to the Qi communication-based feedback control system, resulting in signals that can override controls that stop overcharging, which can lead to overheating, and in some cases a fire. They call such an attack a "VoltSchemer."
    The research team has come up with three types of attacks that can occur with a VoltSchemer. According to the researchers, "A charger can be manipulated to control voice assistants via inaudible voice commands, damage devices being charged through overcharging or overheating, and bypass Qi-standard specified foreign-object-detection mechanism to damage valuable items exposed to intense magnetic fields."

    The researchers tested multiple types of wireless chargers and phones and found they were all vulnerable. They have notified manufacturers and expect that changes will be made to overcome these vulnerabilities to protect consumers from VoltSchemer attacks.

    Zihao Zhan et al, VoltSchemer: Use Voltage Noise to Manipulate Your Wireless Charger, arXiv (2024). DOI: 10.48550/arxiv.2402.11423

  • Dr. Krishna Kumari Challa

    First-in-humans discovery reveals brain chemicals at work influencing social behaviour

    In a study in Nature Human Behavior, scientists delve into the world of chemical neuromodulators in the human brain, specifically dopamine and serotonin, to reveal their role in social behaviour.

    The research, conducted in Parkinson's disease patients undergoing brain surgery while awake, homed in on the brain's substantia nigra, a crucial area associated with motor control and reward processing.

     The international team of scientists revealed a previously unknown neurochemical mechanism for a well-known human tendency to make decisions based on social context—people are more likely to accept offers from computers while rejecting identical offers from human players.

    The idea that people make decisions based on social context is not a new one in neural economic games. But now, for the first time, researchers show the impact of the social context may spring from the dynamic interactions of dopamine and serotonin.

    When people make decisions, dopamine seems to closely follow and react to whether the current offer is better or worse than the previous one, as if it were a continuous tracking system. Serotonin, meanwhile, appears to focus only on the current value of the specific offer at hand, suggesting a more case-by-case evaluation.

    This fast dance happens against a slower backdrop, where dopamine is overall higher when people play other human beings—in other words when fairness comes into play. Together, these signals contribute to our brain's overall assessment of value during social interactions.

    Part 1

  • Dr. Krishna Kumari Challa

    Dopamine levels are higher when people interact with another human as opposed to a computer. And here it was important that the scientists also measured serotonin to give them confidence that the overall response to social context is specific to dopamine.
    Scientists have seen these signaling molecules before, but this is the first time they have seen them dance. No one has ever seen this dance of dopamine and serotonin in a social context before.
    --
    Teasing out the meaning of the electrochemical signals recorded from patients in surgery was a major challenge that took years to solve. The raw data that they're collecting from patients isn't specific to dopamine, serotonin, or norepinephrine—it's a mixture of those. They 're essentially using machine-learning type tools to separate what's in the raw data, understand the signature, and decode what's going on with dopamine and serotonin.
    In the new Nature Human Behavior study, researchers showed how the rise and fall of dopamine and serotonin are intertwined with human cognition and behaviour.
    In Parkinson's disease, a significant loss of dopamine-producing neurons in the brainstem is a key characteristic that usually coincides with the onset of symptoms.

    This loss impacts the striatum, a brain region heavily influenced by dopamine. As dopamine diminishes, serotonin terminals begin to sprout, revealing a complex interaction, as observed in rodent models.
    Part 2

  • Dr. Krishna Kumari Challa

    Psychiatry is an example of a medical field that could benefit from this approach, according to the researchers.

    Enormous number of people in the world suffer from a variety of psychiatric conditions, and, in many cases, the pharmacological solutions do not work very well.
    Dopamine, serotonin, and other neurotransmitters are in some ways intimately involved with those disorders. This effort adds real precision and quantitation to understand those problems. The one thing scientists can be sure of is this work is going to be extremely important in the future for developing treatments.

    In first-of-their-kind observations in the human brain the scientists published in Neuron in 2020, researchers revealed dopamine and serotonin are at work at sub-second speeds to shape how people perceive the world and take action based on their perception.

    More recently, in a study published in October in the journal Current Biology, the researchers used their method of recording chemical changes in awake humans to gain insight into the brain's noradrenaline system, which has been a longtime target for medications to treat psychiatric disorders.

    And, in December, in the journal Science Advances, the team revealed that fast changes in dopamine levels reflect a specific computation related to how humans learn from rewards and punishments.

    Part 3

  • Dr. Krishna Kumari Challa

    Scientists made active measurements of neurotransmitters multiple times in different brain regions, and they have now reached the point where they are touching on crucial elements of what makes us human beings.

    Dopamine and serotonin in human substantia nigra track social context and value signals during economic exchange, Nature Human Behaviour (2024). DOI: 10.1038/s41562-024-01831-wwww.nature.com/articles/s41562-024-01831-w

    Part 4

  • Dr. Krishna Kumari Challa

    Drug limits dangerous reactions to allergy-triggering foods, pediatric study finds

    A drug can make life safer for children with food allergies by preventing dangerous allergic responses to small quantities of allergy-triggering foods, according to a new study by scientists.

     The research published on Feb. 25 in the New England Journal of Medicine. The findings suggest that regular use of the drug, omalizumab,  could protect people from severe allergic responses, such as difficulty breathing, if they accidentally eat a small amount of a food they are allergic to.

    This is a  promising new treatment for multi-food allergic patients.

    Omalizumab, which the Food and Drug Administration originally approved to treat diseases such as allergic asthma and chronic hives, binds to and inactivates the antibodies that cause many kinds of allergic disease. Based on the data collected in the new study, the FDA approved omalizumab for reducing risk of allergic reactions to foods on Feb. 16.

    Omalizumab was safe and did not cause side effects, other than some instances of minor reactions at the site of injection. This study marks the first time its safety has been assessed in children as young as 1.

    New England Journal of Medicine (2024). DOI: 10.1056/NEJMoa2312382

  • Dr. Krishna Kumari Challa

    Blindness from some inherited eye diseases may be caused by gut bacteria, news study suggests

    Sight loss in certain inherited eye diseases may be caused by gut bacteria, and is potentially treatable by antimicrobials, finds a new study in mice.

     The international study observed that in eyes with sight loss caused by a particular genetic mutation, known to cause eye diseases that lead to blindness, gut bacteria were found within the damaged areas of the eye.

    The authors of the new paper, published  in Cell say their findings suggest that the genetic mutation may relax the body's defenses, thus allowing harmful bacteria to reach the eye and cause blindness.

    The gut contains trillions of bacteria, many of which are key to healthy digestion. However, they can also be potentially harmful.

    The findings of this study suggest that simply using antimicrobials might help prevent deterioration in CRB1-associated inherited eye diseases. Future work will investigate whether this applies in humans.

    CRB1-associated retinal degeneration is dependent on bacterial translocation from the gut, Cell (2024). DOI: 10.1016/j.cell.2024.01.040www.cell.com/cell/fulltext/S0092-8674(24)00108-9

  • Dr. Krishna Kumari Challa

    Rural communities face greater risks of radon exposure compared to urban areas: Study

    Researchers have found a link between radon exposure in rural homes based on how close they are to drilled groundwater wells. The transdisciplinary team was investigating why homes in rural communities often have a much higher concentration of radon compared with homes in urban areas.

    The researchers from the faculties of medicine, science, and architecture looked at the geophysical makeup of areas, the style of home, as well as unique features on or near the property.

    For years now all across the world, people have documented higher radon levels in homes in more rural communities compared to homes in urban communities.

    It's the water wells—not the water, but the wells themselves appear to be acting as unintended straws for radon gas deep in the ground. Thankfully, lowering radon levels in a home is fixable.

    Many rural properties and communities rely on well water. The researchers also tested the water for radon and found there is not enough radon in the well water to significantly contribute to the high radon being observed in indoor air. Instead, the problem appears to result from the drill hole space existing around water well pipes.

    Radon is an invisible, odorless, tasteless, and radioactive gas. Naturally rising from under the ground and diluting to virtually nothing in outdoor air, radon gas is often drawn up and concentrated inside modern buildings to unnaturally high and cancer-causing levels. Prolonged radon gas exposure is the leading cause of lung cancer among non-tobacco users.

    The study, published in Scientific Reports, found, on average, individuals living in rural communities were exposed to 30 percent higher residential radon levels than people living in urban communities.

     Selim M. Khan et al, Rural communities experience higher radon exposure versus urban areas, potentially due to drilled groundwater well annuli acting as unintended radon gas migration conduits, Scientific Reports (2024). DOI: 10.1038/s41598-024-53458-6

  • Dr. Krishna Kumari Challa

    Cosmic dust could have helped get life going on Earth

    Life on our planet appeared early in Earth's history. Surprisingly early, since in its early youth our planet didn't have much of the chemical ingredients necessary for life to evolve. Since prebiotic chemicals such as sugars and amino acids are known to appear in asteroids and comets, one idea is that Earth was seeded with the building blocks of life by early cometary and asteroid impacts. While this likely played a role, a new study published in Nature Astronomy shows that cosmic dust also seeded young Earth, and it may have made all the difference.

    Craig R. Walton et al, Cosmic dust fertilization of glacial prebiotic chemistry on early Earth, Nature Astronomy (2024). DOI: 10.1038/s41550-024-02212-z

  • Dr. Krishna Kumari Challa

    Microplastics Found in Every Human Placenta Tested, Study Finds

    It's been over three years since scientists first found microplastics swimming in four different human placentas, and as it turns out, that was just the tip of the iceberg. A few years later, at the start of 2023, researchers announced they had found microscopic particles of plastic waste in no fewer than 17 different placentas. By the end of 2023, a local study in Hawai'i analyzed 30 placentas that were donated between 2006 and 2021 only to find plastic contamination had increased significantly over time. Using a new technique, researchers have now identified tiny particles and fibers of plastic less than a micron in size in the largest sample of placentas yet. In all 62 tissue samples studied, the team found microplastics of various concentrations in every single one. These concentrations ranged from 6.5 to 685 micrograms per gram of tissue, which is much higher than levels found in the human bloodstream. No one yet knows what this plastic pollution is doing – if anything – to the health of the fetus or the mother. While microplastics have been found in every major organ of the human body, including the brain, it's unknown if these pollutants are temporary visitors or permanent and accumulating threats to health. As environmental plastic pollution continues to worsen, contamination of the placenta is on track to only increase, as humans breathe in and ingest more plastic than ever before.

    And dose makes the poison!

    https://academic.oup.com/toxsci/advance-article-abstract/doi/10.109...

  • Dr. Krishna Kumari Challa

    Lake bottom testing shows plastics migrating down into sediment layers

    A team of environmentalists, geographers and ecologists affiliated with several institutions in Europe has found that microplastics have migrated into multiple sediment layers in three lakes in Latvia. In their study, published in the journal Science Advances, the group drilled core samples from three lakes in Latvia and analyzed their contents for microplastics.

    Research over the past few years has shown that microplastics have become pervasive around the planet, from soil where food is grown, to rivers, lakes and streams—and even the clouds. Prior research has also suggested that the Earth has entered a new geological age, moving from the Holocene Epoch to the Anthropocene, a change that most in the Earth science community believe began in the 1950s.

    Most also agree that the transition is the result of human impact. And because plastics have been tied to so many of the changes that have occurred, some suggest using its presence as a barometer to measure the start of the Anthropocene. In this new study, the research team working in Latvia has found that doing so many not be feasible.

    The work involved collecting core sediment samples from the bottom of three lakes in Latvia. Each of the samples was then analyzed to measure amounts of plastic. At the outset, the researchers assumed that sample portions preceding the creation and use of plastics would be zero. Unfortunately, that was not the case.

    The researchers found plastics in sediment that had been deposited as far back as the early 1700s, a finding that indicates that plastics can migrate through sediment down to lower layers. This finding prevents the use of plastics as a barometer for the onset of the Anthropocene.

    The researchers also note that because there are so many factors involved, including the type of soil that makes up sediment, material in the water and its temperature, and the many types of plastics found, studying their source would prove to be exceedingly challenging.

    Inta Dimante-Deimantovica et al, Downward migrating microplastics in lake sediments are a tricky indicator for the onset of the Anthropocene, Science Advances (2024). DOI: 10.1126/sciadv.adi8136

  • Dr. Krishna Kumari Challa

    Nanotweezers manipulate bacteriophages with minimal optical power, a breakthrough for phage therapy

    Scientists  have developed a game-changing technique that uses light to manipulate and identify individual bacteriophages without the need for chemical labels or bioreceptors, potentially accelerating and revolutionizing phage-based therapies that can treat antibiotic-resistant bacterial infections.

    With antibiotic resistance looming as a formidable threat to our health, scientists are on a constant quest for alternative ways to treat bacterial infections. As more and more bacterial strains outsmart drugs we have been relying on for decades, a possible alternative solution may be found in bacteriophages, which are viruses that prey on bacteria.

    Phage therapy, the use of bacteriophages to combat bacterial infections, is gaining attraction as a viable alternative to traditional antibiotics. But there is a catch: Finding the right phage for a given infection is like searching for a needle in a haystack, while current methods involve cumbersome culturing, time-consuming assays.

    Now, scientists  have developed on-chip nanotweezers that can trap and manipulate individual bacteria and virions (the infectious form of a virus) using a minimal amount of optical power. The study is published in the journal Small.

    The nanotweezers are a type of optical tweezers, scientific instruments that use a highly focused laser beam to hold and manipulate microscopic (e.g., virions) and even sub-microscopic objects like atoms in three dimensions. The light creates a gradient force that attracts the particles towards a high-intensity focal point, effectively holding them in place without physical contact.

    Part 1

  • Dr. Krishna Kumari Challa

    There are different types of optical tweezers. For example, free-space optical tweezers can manipulate an object in an open environment such as air or liquid without any physical barriers or structures guiding the light. But in this study, the researchers built nanotweezers embedded in an optofluidic device that integrates optical and fluidic technologies on a single chip.

    The chip contains silicon-based photonic crystal cavities—the nanotweezers, which are essentially tiny traps that gently nudge the phages into position using a light-generated force field. The system allowed the researchers to precisely control single bacteria and single virions and acquire information about the trapped microorganisms in real time.

    What sets this approach apart is that it can distinguish between different types of phages without using any chemical labels or surface bioreceptors, which can be time-consuming and sometimes ineffective. Instead, the nanotweezers distinguish between phages by reading the unique changes each particle causes in the light's properties. The label-free method can significantly accelerate the selection of therapeutic phages, promising faster turnaround for potential phage-based treatments.
    The research also has implications beyond phage therapy. Being able to manipulate and study single virions in real time opens up new avenues in microbiological research, offering scientists a powerful tool for rapid testing and experimentation. This could lead to a deeper understanding of viruses and their interactions with hosts, which is invaluable in the ongoing battle against infectious diseases.

    Nicolas Villa et al, Optical Trapping and Fast Discrimination of Label‐Free Bacteriophages at the Single Virion Level, Small (2024). DOI: 10.1002/smll.202308814

    Part 2

  • Dr. Krishna Kumari Challa

    You may be breathing in more tiny nanoparticles from your gas stove than from car exhaust

    A new study has found that cooking on your gas stove can emit more nano-sized particles into the air than vehicles that run on gas or diesel, possibly increasing your risk of developing asthma or other respiratory illnesses.

    Combustion remains a source of air pollution across the world, both indoors and outdoors. Researchers found that cooking on your gas stove produces large amounts of small nanoparticles that get into your respiratory system and deposit efficiently.

    Based on these findings, the researchers would encourage turning on a kitchen exhaust fan while cooking on a gas stove.

    Recent studies have found that children who live in homes with gas stoves are more likely to develop asthma. But not much is known about how particles smaller than 3 nanometers, called nanocluster aerosol, grow and spread indoors because they're very difficult to measure. These super tiny nanoparticles are so small that you're not able to see them. They're not like dust particles that you would see floating in the air. After observing such high concentrations of nanocluster aerosol during gas cooking, we can't ignore these nano-sized particles anymore, say scientists. This would mean that adults and children could be breathing in 10 to 100 times more nanocluster aerosol from cooking on a gas stove indoors than they would from car exhaust while standing on a busy street.

    Since most people don't turn on their exhaust fan while cooking, having kitchen hoods that activate automatically would be a logical solution.

     Brandon Boor et al, Dynamics of nanocluster aerosol in the indoor atmosphere during gas cooking, PNAS Nexus (2024). DOI: 10.1093/pnasnexus/pgae044academic.oup.com/pnasnexus/art … /3/2/pgae044/7614671

  • Dr. Krishna Kumari Challa

    AI reveals prostate cancer is not just one disease

    Artificial Intelligence has helped scientists reveal a new form of aggressive prostate cancer that could revolutionize how the disease is diagnosed and treated in the future.

    The study published in Cell Genomics reveals that prostrate cancer, which affects one in eight men in their lifetime, includes two different subtypes termed evotypes.

    The discovery was made by an international team led by the University of Oxford, and the University of Manchester, who applied AI on data from DNA to identify two different subtypes affecting the prostate.

    The team hopes their findings could save thousands of lives in future and revolutionize how prostate cancer is diagnosed and treated. Ultimately, it could provide tailored treatments to each individual patient according to a genetic test which will also be delivered using AI.

    This understanding is pivotal as it allows us to classify tumors based on how the cancer evolves rather than solely on individual gene mutations or expression patterns.

    The researchers used AI to study changes in the DNA of prostate cancer samples (using whole genome sequencing) from 159 patients.

    They identified two distinct cancer groups among these patients using an AI technique called neural networks. These two groups were confirmed by using two other mathematical approaches applied to different aspects of the data. This finding was validated in other independent datasets from Canada and Australia.

    They went on to integrate all the information to generate an evolutionary tree showing how the two subtypes of prostate cancer develop, ultimately converging into two distinct disease types termed "evotypes."

    Genomic evolution shapes prostate cancer disease type, Cell Genomics (2024). DOI: 10.1016/j.xgen.2024.100511www.cell.com/cell-genomics/ful … 2666-979X(24)00038-7

  • Dr. Krishna Kumari Challa

    Taking the motion sickness out of space travel

    In lab experiments, aerospace engineers spin and rock human subjects--all in an effort to help prevent motion sickness when astronauts return to Earth and land in the choppy ocean.

  • Dr. Krishna Kumari Challa

    How humans lost their tails
    Researchers have shown that humans and other apes carry a DNA insertion in a gene called TBXT that other primates with tails, such as monkeys, don’t have. And mice carrying similar alterations to their genomes have short or absent tails. “They clearly show that this change contributes to tail loss. But it’s not the only one,” says human geneticist Malte Spielmann. Apes aren’t the only primates without tails, suggesting that the trait evolved multiple times. “Probably, there are multiple ways of losing a tail during development. Our ancestors chose this way,” says co-author Bo Xia.

    https://www.nature.com/articles/d41586-024-00610-x?utm_source=Live+...

  • Dr. Krishna Kumari Challa

    ‘Epigenetic’ editing cuts cholesterol in mice

    An alternative to genome editing can reduce the activity of a gene that affects cholesterol levels without changing the DNA sequence — and does so for an extended period, according to a study1 in mice.

    Scientists achieved this effect by changing each animal’s ‘epigenome’, one feature of which is a collection of chemical tags that are bound to DNA and affect gene activity. After the treatment, activity of the targeted gene dropped and remained low for the 11 months over which the mice were studied.

    https://www.nature.com/articles/d41586-024-00563-1?utm_source=Live+...