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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

    Some countries could meet their total electricity needs from floating solar panels, research shows

    Floating solar photovoltaic panels could supply all the electricity needs of some countries, new research has shown.

    The study 's aimed to calculate the global potential for deploying low-carbon floating solar arrays. The researchers calculated the daily electrical output for floating photovoltaics (FPVs) on nearly 68,000 lakes and reservoirs around the world, using available climate data for each location.

    The researchers' calculations included lakes and reservoirs where floating solar technology is most likely to be installed. They were no more than 10km from a population center, not in a protected area, didn't dry up and didn't freeze for more than six months each year. The researchers calculated output based on FPVs covering just 10% of their surface area, up to a maximum of 30 km2.

    While output fluctuated depending on altitude, latitude and season, the potential annual electricity generation from FPVs on these lakes was 1,302 terawatt hours (TWh), around four times the total annual electricity demand of the UK.

    FPVs have a number of additional advantages over land-based solar installations: they free up land for other uses and they keep panels cooler, making them more efficient.

    There is some evidence for other environmental benefits, including reducing water loss through evaporation, by sheltering the lake surface from the sun and wind; and reducing algal blooms by limiting light and preventing nutrient circulation.

    However, the researchers point out that we still don't know exactly how floating panels might affect the ecosystem within a natural lake, in different conditions and locations. But the potential gain in energy generation from FPVs is clear, so we need to put that research in place so this technology can be safely adopted. 

     Decarbonisation potential of floating solar photovoltaics on lakes worldwide, Nature Water (2024). DOI: 10.1038/s44221-024-00251-4www.nature.com/articles/s44221-024-00251-4

  • Dr. Krishna Kumari Challa

    Study finds maternal obesity in mice increases microRNA levels in the hypothalamus in offspring, leading to overeating

    Maternal obesity impacts the eating behaviours of offspring via long-term overexpression of the microRNA miR-505-5p, according to a study publishing June 4 in the open-access journal PLOS Biology.

     Previous studies in both humans and animal models have shown that the offspring of obese mothers have a higher risk of obesity and type 2 diabetes. While this relationship is likely the result of a complex relationship between genetics and environment, emerging evidence has implicated that maternal obesity can disrupt the hypothalamus—the region of the brain responsible for nutrition sensing and energy homeostasis.

    In animal models, offspring exposed to overnutrition during key periods of development eat more, but little is known about the molecular mechanisms that lead to these changes in eating behaviour.

    In this new study, researchers found that mice born from obese mothers had higher levels of the microRNA miR-505-5p in their hypothalamus—from as early as the fetal stage into adulthood. The researchers found that the mice ate more and showed a preference for high-fat foods. Interestingly, the effect of maternal obesity on miR-505-5p and eating behaviours was mitigated if the mothers exercised during pregnancy.

    Cell culture experiments showed that miR-505-5p expression could be induced by exposing hypothalamic neurons to long-chain fatty acids and insulin, which are both high in pregnancies complicated by obesity. The researchers identified miR-505-5p as a novel regulator of pathways involved in fatty acid uptake and metabolism, therefore, high levels of the miRNA make the offspring brain unable to sense when eating high fat foods.

    Several of the genes that miR-505-5p regulates have been associated with high body mass index in human genetic studies. The study is one of the first to demonstrate the molecular mechanism linking nutritional exposure in utero to eating behaviour.

    This research work helps us understand why the children of mothers living with obesity are more likely to become obese themselves, with early life exposures, genetics and current environment all being contributing factors.

    Dearden L, Furigo IC, Pantaleão LC, Wong LWP, Fernandez-Twinn DS, de Almeida-Faria J, et al. Maternal obesity increases hypothalamic miR-505-5p expression in mouse offspring leading to altered fatty acid sensing and increased intake of high-fat food. PLoS Biology (2024). DOI: 10.1371/journal.pbio.3002641

  • Dr. Krishna Kumari Challa

    Commonly used alcohol-based mouthwash brand may disrupt the balance of your oral microbiome, scientists say

    The oral microbiome is the community of bacteria that live in the mouth. It helps us digest our food and keep our mouth healthy. Changes to the composition of the oral microbiome have been linked to periodontal diseases and some cancers.

    New research, published in Journal of Medical Microbiology is a follow-up to a larger study investigating the use of mouthwash as a method to reduce the transmission of sexually transmitted diseases in men who have sex with men. Researchers wanted to explore further and investigate whether the mouthwash used had an impact on the oral microbiome of the patients.

    Researchers found that two species of opportunistic bacteria were significantly more abundant in the mouth after three months of daily use of the alcohol-based mouthwash, Fusobacterium nucleatum and Streptococcus anginosus. These two bacteria have been previously linked to gum disease, esophageal and colorectal cancers. Researchers also saw a decrease in a group of bacteria called Actinobacteria, which are crucial contributors to the regulation of blood pressure.

    Alcohol-based mouthwashes are widely available. The public may use them daily to tackle bad breath or prevent periodontitis, but they should be aware of the potential implications.

    The effect of daily usage of Listerine Cool Mint mouthwash on the oropharyngeal microbiome: a substudy of the PReGo trial, Journal of Medical Microbiology (2024). DOI: 10.1099/jmm.0.001830

  • Dr. Krishna Kumari Challa

    New model suggests partner anti-universe could explain accelerated expansion without the need for dark energy

    The accelerated expansion of the present universe, believed to be driven by a mysterious dark energy, is one of the greatest puzzles in our understanding of the cosmos. The standard model of cosmology called Lambda-CDM, explains this expansion as a cosmological constant in Einstein's field equations. However, the cosmological constant itself lacks a complete theoretical understanding, particularly regarding its very small positive value.

    To explain the accelerated expansion, physicists have proposed alternative explanations such as quintessence and modified gravity theories, including scalar-tensor-vector gravity. Additionally, explanations beyond four dimensions, like the braneworld scenarios in the Dvali-Gabadadze-Porrati (DGP) model, modify gravity at large distances due to the effect of a higher-dimensional bulk on our four-dimensional brane, and variable brane tension.

    Some researchers are now proposing another model to explain the present accelerated expansion of the universe. Unlike existing models, this does not require any form of dark energy or modified gravity approaches. However, there is a price to pay: we need a partner anti-universe whose time flow is oppositely related to our universe.

    There are strong arguments supporting this concept. From a quantum theory perspective, it is natural for the universe to be created in pairs. Recently, Boyle et al proposed that the universe does not spontaneously violate CPT (Charge, Parity, and Time reversal symmetry), but rather, the universe after the Big Bang is the CPT image of the universe before it, pointing towards a partner anti-universe.

    In a recent paper published in Gravitation and Cosmology, researchers used key concepts from quantum theory, such as relative entropy, and from general relativity, such as the null energy condition, which corresponds to the positive energy condition. The findings suggest that the universe naturally expands in an accelerated manner.

    Part 1
  • Dr. Krishna Kumari Challa

    Relative entropy, which requires two states, in this case, corresponds to the universe and its partner anti-universe. Accelerated expansion seems inevitable in a universe created in pairs that respect the null energy condition. This result is quite surprising and readers familiar with Hawking's area theorem may notice some similarities. The area theorem also deals with causal horizons and requires the null energy condition to hold.

    In this new model, the causal horizon corresponds to the Big Bang. The results apply equally to the partner anti-universe.

     Naman Kumar, On the Accelerated Expansion of the Universe, Gravitation and Cosmology (2024). DOI: 10.1134/S0202289324010080

    Part 2

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  • Dr. Krishna Kumari Challa

    Nocturnal heat exposure and stroke risk

    Hot Nights Linked With Increased Risk of Stroke, Scientists Warn

    The risk of suffering a stroke is significantly higher with high overnight temperatures, posing a potential health concern around the globe as the world gets warmer.

    Mapping night-time temperatures against the number of stroke cases recorded in the German city of Augsburg across the course of 15 years, a research team found a statistically significant increase in stroke risk on days where extremely warm night-time temperatures were recorded, with older people and women particularly vulnerable.

    Overall, the risk of stroke increased by 7 percent during nights categorized as "tropical". For the purposes of this research, a tropical night was one where the temperature remained above 14.6 °C (58.3 °F). These nights represented the hottest 5 percent of nights across the course of the study period.

    There was evidence of a higher number of stroke incidents over time, too: from 2006 to 2012, hot nights were linked to two additional strokes per year, whereas from 2013 to 2020, hot nights were associated with 33 additional cases per year. That reflects increasing temperatures as the years went by.

    The researchers say a variety of factors could be behind the statistics, including a greater chance of dehydration – already known to increase the likelihood of suffering a stroke. Limited access to technology such as air conditioning could also play a part.

    https://academic.oup.com/eurheartj/advance-article/doi/10.1093/eurh...

    "In summary, changes in underlying drivers from climatic factors, stroke risk factors, and socioeconomic conditions may contribute to the increased susceptibility to night-time heat-related stroke over time," write the researchers in their published paper.

  • Dr. Krishna Kumari Challa

    'Painting with light' illuminates photo evidence of air pollution

    Researchers and artists have joined forces to "paint with light"—making invisible air pollution visible and demonstrating the health risks posed to people living and working in Ethiopia, India, and the UK.

    Combining digital light painting and low-cost air pollution sensors, the team produced photographic evidence of pollution levels in cities across the three countries—sparking debate among local communities and illustrating:

    • Air pollution varying dramatically between locations in Ethiopia—a kitchen using biomass stoves for food preparation where PM2.5 concentrations in the room were up to 20 times greater than what was measured nearby outdoors;
    • Two children's playgrounds in India, 500 km apart—one in urban Delhi, the other in rural Palampur—with PM2.5 values at the Palampur playground at least 12.5 times less than those measured in Delhi; and
    • Large variations in air pollution around the Port Talbot steelworks, in Wales—air quality monitoring and light painting at dusk in summer measured PM2.5 concentrations in the range of 30-40 mg/m3, when the hourly average value was 24 mg/m3.
    The international team of researchers and artists published its findings in Communications Earth & Environment—recording how photographs taken as part of the "Air of the Anthropocene" project had stimulated discussion around the impact of air pollution.
    The team used low-cost air pollution sensors to measure PM mass concentrations and took the sensors' real time signal to control a moving LED array programmed to flash more rapidly as PM concentration increased.
    A long exposure photograph is taken with the artist moving the LED array in front of the camera—the flash becoming a dot on the photograph. The artist is not seen in the photo because they are moving, but light flashes from LEDs are seen because they are bright. The more light dots appear in the photographs, the higher the PM concentration.
    Thanks to the power of images, these people could provoke people's emotions—fostering awareness and prompting people to share their perspectives and take action to tackle air pollution.
    Light painting photography makes particulate matter air pollution visible, Communications Earth & Environment (2024).
  • Dr. Krishna Kumari Challa

    Rate of global warming caused by humans is at an all-time high, say scientists

    The second annual Indicators of Global Climate Change report reveals that human-induced warming has risen to 1.19 °C over the past decade (2014-2023)—an increase from the 1.14 °C seen in 2013-2022 (set out in last year's report).

    Looking at 2023 in isolation, warming caused by human activity reached 1.3 °C. This is lower than the total amount of warming we experienced in 2023 (1.43 °C), indicating that natural climate variability, in particular El Niño, also played a role in 2023's record temperatures.

    The analysis also shows that the remaining carbon budget—how much carbon dioxide can be emitted before committing us to 1.5 °C of global warming—is only around 200 gigatons (billion tons), around five years' worth of current emissions.

    In 2020, the Intergovernmental Panel on Climate Change (IPCC) calculated that the remaining carbon budget for 1.5 °C was in the 300–900 gigatonnes of carbon dioxide range, with a central estimate of 500. Since then, CO2 emissions and global warming have continued. At the start of 2024, the remaining carbon budget for 1.5 °C stood at 100 to 450 gigatons, with a central estimate of 200.

    This analysis by scientists shows that the level of global warming caused by human action has continued to increase over the past year, even though climate action has slowed the rise in greenhouse gas emissions. Global temperatures are still heading in the wrong direction and faster than ever before.

    The latest Indicator report, which is published by more than 50 scientists in the journal Earth System Science Data, also provides new insight into the effects of reductions in sulfur emissions from the global shipping industry. The sulfur has a cooling effect on the climate by directly reflecting sunlight back to space and by helping more reflective clouds to form, but ongoing reductions in those emissions have lessened that effect.

    Although this was offset last year by the aerosol emissions from the Canadian wildfires, the report says the longer-term trend nonetheless indicates that the amount of cooling we can expect from aerosol emissions is continuing to decline.

     Indicators of Global Change report, Earth System Science Data (2024).

  • Dr. Krishna Kumari Challa

    Scientists sound the alarm on pharmaceutical pollution crisis

    Our increasing dependency on pharmaceuticals comes at a major environmental cost, researchers have warned.

    In an article published in the journal Nature Sustainability, researchers warn that discharges to the environment during drug production, use, and disposal have resulted in ecosystems around the globe being polluted with mixtures of pharmaceuticals, posing a growing danger to wildlife and human health.

    While emphasizing that pharmaceuticals are indispensable in modern health care and will remain crucial in the future, the researchers highlight the need for designing and manufacturing more sustainable drugs to combat this issue at source.

    A wide variety of drugs have now been detected in environments spanning all continents on Earth.

    Exposure to even trace concentrations of some of these drugs can have severe impacts on the health of wildlife and human populations, and has already led to severe population crashes in vultures throughout India and Pakistan, as well as widespread sex-reversal of fish populations exposed to the human contraceptive pill.

    Pharmaceutical pollution is a complex problem that demands a multifaceted solution. So far, environmental protection efforts have mainly been focused on upgrading wastewater treatment infrastructure to remove drugs before release into waterways more effectively.

    Part 1

  • Dr. Krishna Kumari Challa

    Despite being an important part of an overall solution, wastewater treatment is unable to address this issue in isolation.

    In the article, 17 leading international scientists call for an increased focus on designing greener and more sustainable pharmaceuticals to tackle this issue at its source.

    Tomas Brodin et al, The urgent need for designing greener drugs, Nature Sustainability (2024). DOI: 10.1038/s41893-024-01374-y

    Part 2

  • Dr. Krishna Kumari Challa

    Scientists develop electrified charcoal 'sponge' that can soak up CO₂ directly from the air

    Researchers have developed a low-cost, energy-efficient method for making materials that can capture carbon dioxide directly from the air.

    They used a method similar to charging a battery to instead charge activated charcoal, which is often used in household water filters.

    By charging the charcoal 'sponge' with ions that form reversible bonds with CO2, the researchers found the charged material could successfully capture CO2 directly from the air.

    The charged charcoal sponge is also potentially more energy efficient than current carbon capture approaches, since it requires much lower temperatures to remove the captured CO2 so it can be stored. The results are reported in the journal Nature.

    Alexander Forse et al, Capturing carbon dioxide from air with charged-sorbents, Nature (2024). DOI: 10.1038/s41586-024-07449-2www.nature.com/articles/s41586-024-07449-2

  • Dr. Krishna Kumari Challa

    Study shows orexin neurons can track how fast blood glucose changes
    The concentration of glucose in the blood of humans continuously changes in response to what they eat and the activities they engage in. While many studies have investigated changes in blood glucose, the role of different neurons in tracking and predicting these changes remains poorly understood.
    Researchers recently carried out a study investigating the potential role of a specific type of neuron, called orexin neurons, in tracking blood glucose levels. Their findings, published in Nature Neuroscience, suggest that orexin neurons in the mouse brain are responsible for tracking how fast blood glucose levels are changing.

    In the 2000s, a lot of scientific effort went into identifying the so-called 'glucose-sensing neurons,' since these cells may alter our brain function based on what is happening minute-to-minute inside our body. With the huge 'diabesity [diabetes + obesity] epidemic' happening in some countries this was also important because sugar was implicated. Between 2005 and 2011, Burdakov's research lab contributed to the identification and characterization of glucose-sensing in orexin neurons. These are specialized neurons that have been found to sense glucose and produce the neurotransmitter orexin/hypocretin.
    Orexin/hypocretin is a chemical "messenger" that contributes to the regulation of various physiological processes, including arousal, wakefulness and appetite. Orexin-producing neurons, identified about three decades ago, are only found in the hypothalamus, yet they innervate the entire central nervous system in humans and other mammals.
    Orexin neurons are so important for our arousal and consciousness that without this small cluster of cells our normal consciousness is lost (as in narcolepsy—which is a disorder caused by loss of orexin cells or orexin in humans)
    Part 1
  • Dr. Krishna Kumari Challa

    Earlier experiments indicated that orexin cells are profoundly silenced by glucose, but that was 'in a dish,' in the experiments in isolated orexin cells. It since transpired that, in the living brain of a behaving mammal, orexin cells are profoundly controlled by many other things, including direct neural inputs from much of the brain.
    The concentration of glucose in the blood is not only controlled by eating and exercising, it is known to also be regulated by the naturally occurring hormone insulin and the liver, which produce dynamic waves of blood glucose. Researchers used their sensors introduced in arteries to monitor these wave-like changes in glucose concentration over time.
    This allowed them to note at what point in the waves (i.e., at their crest, trough, rise, fall) orexin neurons in the mouse brain became excited or fell silent. In addition, the researchers observed the behavior of the mice, particularly their spontaneous running, to determine whether it was influenced by blood glucose in normal mice and in mice that did not have orexin-producing neurons.
    They found that the biggest modulation of orexin cell activity happened during the rise and fall of blood glucose waves. Surprisingly, orexin cells appeared almost blind to absolute levels of blood glucose, but mostly tracked the rises and falls, especially the rate-of-change of glucose during these rises and falls.
    The findings gathered by the researchers highlight the potential role of orexin cells in tracking blood glucose levels, particularly their temporal features (i.e., their changes over time). They thus shed new light on the complex neurobiology of blood glucose perception in the brain.

    Paulius Viskaitis et al, Orexin neurons track temporal features of blood glucose in behaving mice, Nature Neuroscience (2024). DOI: 10.1038/s41593-024-01648-w

    Part 2

  • Dr. Krishna Kumari Challa

    The first example of cellular origami discovered in protist

    Combining a deep curiosity and "recreational biology,"  researchers have discovered how a simple cell produces remarkably complex behavior, all without a nervous system. It's origami, they say.

    It is a  single teardrop-shaped cell that swims in a droplet of pond water. In an instant, a long, thin "neck" projects out from the bulbous lower end. And it keeps going. And going. Then, just as quickly, the neck retracts back, as if nothing had happened.

    In seconds, a cell that was just 40 microns tip-to-tail sprouted a neck that extended 1,500 microns or more out into the world. It is the equivalent of a 6-foot human projecting its head more than 200 feet. All from a cell without a nervous system. All this is because of origami!

    Eliott Flaum et al, Curved crease origami and topological singularities enable hyperextensibility of L. olor, Science (2024). DOI: 10.1126/science.adk5511www.science.org/doi/10.1126/science.adk5511

  • Dr. Krishna Kumari Challa

    Study links nanoparticles to altered blood vessel formation in embryos

    Human life begins with a single egg cell that grows into a human being with trillions of cells. To ensure that the highly complex development of tissues and organs is as protected as possible, the placental barrier keeps pathogens and foreign substances out. Some researchers are investigating how this protective mechanism copes with nanoparticles.

    The findings are published in the journal Advanced Science.

    Nanoparticles are contained in a large number of products, but they are also produced during wear and tear as well as through combustion processes. We absorb these substances from the environment via our food, cosmetics or the air we breathe.

    Some of these nanoparticles are suspected of harming babies in the womb. Low birth weight, autism and respiratory diseases are among the possible consequences for the child.

    It is still unclear how the nanoparticles affect the unborn child. We already know that the placental barrier retains many nanoparticles or at least delays their transport to the embryo. However, damage to the fetal tissue occurs, even if no particles have been detected in the fetus. The researchers are now getting to the bottom of this long-range effect of nanoparticles. They are investigating the consequences of common nanoparticles such as titanium dioxide or diesel soot on the function of the placenta and their indirect damage to embryonic development.

    For this purpose, the team used fully functional human placentas that were made available after planned cesarean sections. Human placental tissue is the only way to obtain meaningful results on the transport and effect of nanoparticles. The structure, metabolism and interaction of maternal and fetal tissue are unique and species-specific.

    Part 1

  • Dr. Krishna Kumari Challa

    The experiments showed that nanoparticles in placental tissue disrupt the production of a large number of messenger substances. And it is these messengers that can trigger serious changes in embryonic development, such as disturbed blood vessel formation.
    These effects can be visualized in laboratory models using chicken eggs. The blood vessels in the egg actually grow at an enormous speed and density to enable embryonic development. A dense network of fine blood vessels covers the inside of the eggshell.

    The situation is strikingly different in eggs treated with the altered messenger substances from the nanoparticle-treated placenta: In the experiments, the blood vessel system was not as dense but rather coarse-meshed. "Nanoparticles apparently have an indirect effect on the child in the womb by inhibiting the formation of blood vessels via messenger substances.
    The researchers are currently investigating the health consequences of this.

    Battuja Dugershaw‐Kurzer et al, Nanoparticles Dysregulate the Human Placental Secretome with Consequences on Angiogenesis and Vascularization, Advanced Science (2024). DOI: 10.1002/advs.202401060

    Part 2

  • Dr. Krishna Kumari Challa

    Dad’s diet affects sons’ health

    Epigenetic inheritance of diet-induced and sperm-borne mitochondrial RNAs


    A father’s sperm records his diet, which affects his sons’ metabolism — in both mice and in humans. The male offspring of mice that ate high-fat foods were more likely to have problems such as glucose intolerance, a characteristic of diabetes. And the sons of human dads with a high body-mass index had similar problems, according to an analysis of more than 3,000 children. In mice, an unhealthy diet changed certain types of sperm RNA, which could alter the offspring’s epigenome — the collection of chemical tags hanging from DNA and its associated proteins. Why this seems to only affect sons is “a very good question for future studies."

    https://www.nature.com/articles/s41586-024-07472-3?utm_source=Live+...

    https://www.nature.com/articles/d41586-024-01623-2?utm_source=Live+...

  • Dr. Krishna Kumari Challa

    Bird flu in cows could spread through milk
    Astonishing amounts of H5N1 virus have been found in the raw milk of cows infected with avian influenza. The virus can survive for hours in splattered milk. This reinforces that the milking process is probably driving transmission among cows and might be spreading the virus to humans. The fact that H5N1 doesn’t seem to spread through airborne particles is good news. It means changes to milking procedures — such as disinfecting equipment between cows and protective equipment to farm workers — could help to bring the outbreak under control.

    Nature | 5 min read
    Reference: bioRxiv preprint & medRxiv preprint (not peer reviewed)

  • Dr. Krishna Kumari Challa

    Timing drug administration to endogenous circadian rhythms may enhance treatment efficacy

    Taking blood pressure medication at a time that aligns with your personal chronotype – the way your body's circadian rhythm affects when you go to sleep and get up – could help to protect the heart against the risk of heart attack, a new study shows.

    It may be beneficial for night owls to take their medication in the evening, and for early birds to take it in the morning. These timings seem to offer some protection against the risks associated with BP (also known as hypertension). The international team of researchers behind the new study looked at records for more than 5,300 individuals, who answered questions about their chronotype, before being randomly split into groups and instructed to take their blood pressure meds at different times. Participants were then monitored over several months. These results are exciting because they could represent a paradigm shift in the treatment of hypertension. This research has now shown for the first time that considering chronotype when deciding [the] dosing time of antihypertensives – [a strategy called] personalized chronotherapy – could reduce the risk of heart attack. Each person's circadian rhythm (24-hour biological cycle) varies slightly, based on genetics and other factors. These rhythms are well known for influencing our sleep patterns, but they also help to dictate body temperature, hormones, metabolism – and, importantly for this study, BP levels. If blood pressure cycles up and down throughout the day, the time that medications are taken might matter, the researchers hypothesized.

    https://www.thelancet.com/journals/eclinm/article/PIIS2589-5370(24)...

  • Dr. Krishna Kumari Challa

    Microplastics found in every semen sample tested by research team
    A team of public health researchers affiliated with multiple institutions in China has found microplastics in the semen of every sample they tested. In their study, published in the journal Science of the Total Environment, the group looked for microplastics in semen samples obtained from 36 healthy adult men.

    Prior research has shown that microplastics are nearly everywhere, found on mountaintops, remote islands in the upper atmosphere and the depths of the world's oceans. They have also been found in every organ in the human body.

    In a recent discovery, scientists found that the average person consumes plastic in amounts equal to about one credit card every week. The researchers note that plastics can enter the body in multiple ways, such as through drinking from water bottles, breathing air particulates, or eating food heated in plastic containers. They further note that it is now practically impossible for people to avoid ingesting microplastics.

    The health impacts remain unknown, but many scientists around the world are looking into it, suspecting microplastic ingestion may be behind many inflammatory diseases.
    In this new effort, the research team wondered if ingested microplastics might be behind the global drop in fertility rates. To find out, they recruited 36 healthy adult males living in the city of Jinan, in the eastern part of China, who did not work in the plastics industry—each donated a sample of semen for testing.

    Each of the samples was prepared by mixing it with a chemical solution then filtered for analysis by a team member using a microscope. The researchers found microplastics in every sample. They also found eight types of plastics, the most common of which was polystyrene, which is commonly used in packaging foam.
    The team also found lower sperm motility in the semen samples containing polyvinyl chloride plastic bits, a finding that may help explain the decline in fertility rates.

    Ning Li et al, Prevalence and implications of microplastic contaminants in general human seminal fluid: A Raman spectroscopic study, Science of The Total Environment (2024). DOI: 10.1016/j.scitotenv.2024.173522

  • Dr. Krishna Kumari Challa

    Highlights of the study:

    • •An early study to detect microplastics in semen from a general population cohort
    • •Eight MP polymer types were identified, with PS, PE, and PVC most prevalent.
    • •Raman microspectroscopy enabled sub-micron microplastic characterization.
    • •PS and PVC correlated with differential effects on sperm motility.
    • As widespread environmental pollution, MPs/NPs raise concerns about reproductive toxicity.

    • Infertility affects 15 % couples globally, with environmental factors playing a significant role.

    • Limited understanding of MPs/NPs effects on testes and ovaries necessitates further research.

    • Contaminants carried by particles may synergistically contribute to reproductive toxicity.

    https://www.sciencedirect.com/science/article/pii/S0048969723048830

    Part 2

  • Dr. Krishna Kumari Challa

    Researcher suggests that gravity can exist without mass, mitigating the need for hypothetical dark matter

    Dark matter is a hypothetical form of matter that is implied by gravitational effects that can't be explained by general relativity unless more matter is present in the universe than can be seen. It remains virtually as mysterious as it was nearly a century ago when first suggested by Dutch astronomer Jan Oort in 1932 to explain the so-called "missing mass" necessary for things like galaxies to clump together.

    Now Dr. Richard Lieu at The University of Alabama in Huntsville (UAH) has published a paper in the Monthly Notices of the Royal Astronomical Society that shows, for the first time, how gravity can exist without mass, providing an alternative theory that could potentially mitigate the need for dark matter.  

    The researcher contends the "excess" gravity necessary to bind a galaxy or cluster together could be due instead to concentric sets of shell-like topological defects in structures commonly found throughout the cosmos that were most likely created during the early universe when a phase transition occurred. A cosmological phase transition is a physical process where the overall state of matter changes together across the entire universe.

    It is unclear presently what precise form of phase transition in the universe could give rise to topological defects of this sort.

    Topological effects are very compact regions of space with a very high density of matter, usually in the form of linear structures known as cosmic strings, although 2D structures such as spherical shells are also possible.

    Part 1

  • Dr. Krishna Kumari Challa

    The shells in this paper consist of a thin inner layer of positive mass and a thin outer layer of negative mass; the total mass of both layers—which is all one could measure, mass-wise—is exactly zero, but when a star lies on this shell it experiences a large gravitational force pulling it towards the center of the shell.
    As gravitational force fundamentally involves the warping of space-time itself, it enables all objects to interact with each other, whether they have mass or not. Massless photons, for example, have been confirmed to experience gravitational effects from astronomical objects.
    Gravitational bending of light by a set of concentric singular shells comprising a galaxy or cluster is due to a ray of light being deflected slightly inwards—that is, towards the center of the large-scale structure, or the set of shells—as it passes through one shell.
    The sum total effect of passage through many shells is a finite and measurable total deflection which mimics the presence of a large amount of dark matter in much the same way as the velocity of stellar orbits.

    Both the deflection of light and stellar orbital velocities is the only means by which one gauges the strength of the gravitational field in a large-scale structure, be it a galaxy or a cluster of galaxies. The contention of this paper is that at least the shells it posits are massless. There is then no need to perpetuate this seemingly endless search for dark matter.

    Richard Lieu, The binding of cosmological structures by massless topological defects, Monthly Notices of the Royal Astronomical Society (2024). DOI: 10.1093/mnras/stae1258

    Part 2

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  • Dr. Krishna Kumari Challa

    Researchers discover Earth and space share the same turbulence

    In a paper published in Geophysical Research Letters, researchers have discovered that the turbulence in the thermosphere exhibits the same physical laws as the wind in the lower atmosphere. Furthermore, wind in the thermosphere predominantly rotates in a cyclonic direction, in that it rotates counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.

    The findings reveal a new unified principle for the Earth's varied environmental systems and can potentially improve future forecasting of both earth and space weather.

    Facundo L. Poblet et al, Third‐Order Structure Functions of Zonal Winds in the Thermosphere Using CHAMP and GOCE Observations, Geophysical Research Letters (2024). DOI: 10.1029/2024GL108367

  • Dr. Krishna Kumari Challa

    When Water Flows Uphill

  • Dr. Krishna Kumari Challa

    Does magic really exist?

  • Dr. Krishna Kumari Challa

    Study finds fresh water and key conditions for life appeared on Earth a half-billion years earlier than thought

    We need two ingredients for life to start on a planet: dry land and (fresh) water. Strictly, the water doesn't have to be fresh, but fresh water can only occur on dry land.

    Only with those two conditions met can you convert the building blocks of life, amino acids and nucleic acids into tangible bacterial life that heralds the start of the evolutionary cycle.

    The oldest life on Earth left in our fragmented rock record is 3.5 billion years old, with some chemical data showing it may even be as old as 3.8 billion years. Scientists have hypothesized life might be even older, but we have no records of that being the case.

    A new study published in Nature Geoscience provides the first evidence of fresh water and dry land on Earth by 4 billion years ago. Knowing when the cradle of life—water and land—first appeared on Earth ultimately provides clues as to how we came to be.

    Fresh water is very different from sea water. Obviously, you might say, but how do you know if one or both were present on Earth if you can't actually go back in a time machine?

    The answer is in the rock record and chemical signals preserved in that time capsule. Earth is a bit over 4.5 billion years old, and the oldest rocks scientists have found are just a little older than 4 billion years.

    To really understand our planet in its first 500 million years, we have to turn to crystals that once came from older rocks and ended up deposited in younger rocks.

    Unlike rocks, the oldest preserved crystals go back as far as 4.4 billion years. And the bulk of these super-old crystals comes from one place on Earth: the Jack Hills in Western Australia's midwest.

    This is precisely where the researchers of this study went. They dated over a thousand crystals of a mineral called zircon, famed for its extreme resistance to weathering and alteration.

    Part 1

  • Dr. Krishna Kumari Challa

    This work shows that about 10% of all the crystals the researchers analyzed were older than 4 billion years. That might seem small, but it's an enormous amount of super-old grains compared to other places around the world.

    To figure out whether these grains held a record of fresh water, they used tiny beams of ions on these dated zircon grains to measure the ratio of heavier to lighter oxygen. This ratio, known as an oxygen isotopic ratio, is thought to be nearly constant through time for seawater, but much lighter for fresh water.

    Conspicuously, a small portion of zircon crystals from 4 billion years ago had a very light signature that could only have formed from the interaction of fresh water and rocks.
    Zircon is extremely resistant to alteration. For the Jack Hills' zircon to obtain this light oxygen signature, the rock altered by fresh water had to melt and then re-solidify to impart the light oxygen isotopic signature into the zircon.

    Thus, fresh water had to be present on Earth before 4 billion years ago.
    Researchers now at least found evidence for the cradle of life on Earth some time before 4 billion years ago—extremely early in our planet's 4.5-billion-year history..

    Hamed Gamaleldien et al, Onset of the Earth's hydrological cycle four billion years ago or earlier, Nature Geoscience (2024). DOI: 10.1038/s41561-024-01450-0

    Part 2

  • Dr. Krishna Kumari Challa

    Improved prime editing system makes gene-sized edits in human cells at therapeutic levels

    Scientists have improved a gene-editing technology that is now capable of inserting or substituting entire genes in the genome in human cells efficiently enough to be potentially useful for therapeutic applications.

    The advance could one day help researchers develop a single gene therapy for diseases such as cystic fibrosis that are caused by one of hundreds or thousands of different mutations in a gene. Using this new approach, they would insert a healthy copy of the gene at its native location in the genome, rather than having to create a different gene therapy to correct each mutation using other gene-editing approaches that make smaller edits.

    The new method uses a combination of prime editing, which can directly make a wide range of edits up to about 100 or 200 base pairs, and newly developed recombinase enzymes that efficiently insert large pieces of DNA thousands of base pairs in length at specific sites in the genome. This system, called eePASSIGE, can make gene-sized edits several times more efficiently than other similar methods, and is reported in Nature Biomedical Engineering.

    Pandey S, Gao XD, et al. Efficient site-specific integration of large genes in mammalian cells via continuously evolved recombinases and prime editing, Nature Biomedical Engineering (2024). DOI: 10.1038/s41551-024-01227-1

  • Dr. Krishna Kumari Challa

    Compressed titanium and sulfur nanoribbons can transmit electricity without energy loss, scientists find

    When compressed, nanoribbons of titanium and sulfur can change properties dramatically, turning into materials with the ability to conduct electricity without losing energy, according to a study published in the journal Nano Letters.

    The authors have made the discovery during their painstaking search for new materials that can transmit electricity without loss of energy, a hot topic that has for long haunted the scientific community.

    This new research focused on one such promising material: TiS3 nanoribbons, which are tiny, ribbon-like structures made of titanium and sulfur. In their natural state, TiS3 nanoribbons act as insulators, meaning they do not conduct electricity well.  The researchers, however, discovered that by applying pressure to these nanoribbons, we could change their electrical properties dramatically.

    The scientists exposed TiS3 to gradual pressure. As they increased the pressure, they found that the TiS3 system underwent a series of transitions, from being insulators to becoming metals and superconductors, for the first time.

    TiS3 materials are known to work as good insulators, but it is the first time scientists have discovered that under pressure they can function as superconductors, paving the way for the development of superconducting materials.

    Mahmoud Abdel-Hafiez et al, From Insulator to Superconductor: A Series of Pressure-Driven Transitions in Quasi-One-Dimensional TiS3 Nanoribbons, Nano Letters (2024). DOI: 10.1021/acs.nanolett.4c00824

  • Dr. Krishna Kumari Challa

    Study: An estimated 135 million premature deaths linked to fine particulate matter pollution between 1980 and 2020

    A study led by researchers from Nanyang Technological University, Singapore (NTU Singapore) revealed that fine particulate matter from 1980 to 2020 was associated with approximately 135 million premature deaths globally. The findings were published in April in the peer-reviewed journal Environment International.

    In the study, premature deaths refer to fatalities that occur earlier than expected based on average life expectancy, resulting from preventable or treatable causes such as diseases or environmental factors.

    The study found that the impact of pollution from fine particulate matter was worsened by climate variability phenomena such as the El Niño-Southern Oscillation, the Indian Ocean Dipole, and the North Atlantic Oscillation, and led to a 14 percent rise in premature deaths.

    The researchers explain that during such weather events, the increased temperature, changes in wind patterns, and reduced precipitation can lead to stagnant air conditions and the accumulation of pollutants in the atmosphere. These result in higher concentrations of PM2.5 particles that are particularly harmful to human health when inhaled.
    Fine particulate matter, or PM2.5, refers to particulate matter 2.5 micrometers in diameter or smaller. These tiny particles come from vehicle emissions, industrial processes, and natural sources such as wildfires and dust storms.

    As they are so small, PM2.5 particles can easily get into the air we breathe and penetrate deep into our lungs, leading to a range of health problems, especially for vulnerable groups like children, the elderly, and people with respiratory conditions.

    The study estimated that a third of the premature deaths from 1980 to 2020 were associated with stroke (33.3%); another third with ischemic heart disease (32.7%), while chronic obstructive pulmonary disease, lower respiratory infections, and lung cancer made up the rest of premature deaths.

    S.H.L. Yim et al, Global health impacts of ambient fine particulate pollution associated with climate variability, Environment International (2024). DOI: 10.1016/j.envint.2024.108587

  • Dr. Krishna Kumari Challa

    New study helps disentangle role of soil microbes in the global carbon cycle

    When soil microbes eat plant matter, the digested food follows one of two pathways. Either the microbe uses the food to build its own body, or it respires its meal as carbon dioxide (CO2) into the atmosphere.

    Now a research team has, for the first time, tracked the pathways of a mixture of plant waste as it moves through bacteria's metabolism to contribute to atmospheric CO2. The researchers discovered that microbes respire three times as much CO2 from lignin carbons (non-sugar aromatic units) compared to cellulose carbons (glucose sugar units), which both add structure and support to plants' cellular walls.

    These findings help disentangle the role of microbes in soil carbon cycling—information that could help improve predictions of how carbon in soil will affect climate change.

    The study, "Disproportionate carbon dioxide efflux in bacterial metabolic pathways for different organic substrates leads to variable contribution to carbon use efficiency," was published on June 11 in the journal Environmental Science & Technology.

    The carbon pool that's stored in soil is about 10 times the amount that's in the atmosphere.

    What happens to this reservoir will have an enormous impact on the planet. Because microbes can unlock this carbon and turn it into atmospheric CO2, there is a huge interest in understanding how they metabolize plant waste. As temperatures rise, more organic matter of different types will become available in soil. That will affect the amount of CO2 that is emitted from microbial activities.

    Caroll Mendonca et al, Disproportionate carbon dioxide efflux in bacterial metabolic pathways for different organic substrates leads to variable contribution to carbon use efficiency, Environmental Science & Technology (2024). DOI: 10.1021/acs.est.4c01328pubs.acs.org/doi/10.1021/acs.est.4c01328

  • Dr. Krishna Kumari Challa

    Chemists discover spontaneous nanoparticle formation in charged microdroplets

    A team of chemists has found that particles of minerals sometimes break down spontaneously when immersed in charged microdroplets, leading to the formation of nanoparticles.

    In their study, published in the journal Science, the group conducted experiments with minerals and an electrospray device

    Prior research has shown that natural processes often result in the creation of nanoparticles and that many types of such nanoparticles exist in nature. But not much is known about how they are formed. In this new effort, the research team suspected that some of them may be the result of minerals becoming immersed in charged liquid particles. To find out if that might be the case, they designed an experiment to replicate such natural processes.
    The researchers note that charged microdroplets are plentiful in the natural world, found in clouds and sea spray. To create their own charged microdroplets, they used an electrospray device.

    When filled with water and electrically charged, it can produce a mist of charged droplets. In their experiments, the research team added mineral particles to the water before putting it in the spray device. They then captured samples of the charged microdroplets and other materials that were in the mist. They found many instances of nanoparticles being spontaneously expelled from the microdroplets into the air around them.

    The researchers found that shortly after droplet formation, a double electric field was generated across its surface, producing a reactive sphere. That was followed by droplet fission when coulombic energy in the droplet exceeded its surface tension—and that was followed by expulsion of a mineral nanoparticle in the form of a microdroplet.

    B. K. Spoorthi et al, Spontaneous weathering of natural minerals in charged water microdroplets forms nanomaterials, Science (2024). DOI: 10.1126/science.adl3364

    R. Graham Cooks et al, Breaking down microdroplet chemistry, Science (2024). DOI: 10.1126/science.adp7627

  • Dr. Krishna Kumari Challa

    Climate misinformation overshadows record floods worldwide

    Climate skeptics are scapegoating a weather modification technique known as cloud seeding to deny the role of global warming in historic floods that have recently devastated countries from Brazil to Kenya.

    Record rainfall brought to some regions by the natural weather cycle El Niño matches an expected increase in extreme events, experts say.

    But online, false claims have repeatedly been made that geoengineering—not carbon emissions—is to blame.

    Claims that weather had been manipulated appeared after every major flood this year, including in Zimbabwe, the United Arab Emirates and other nations. 

    Cloud seeding, which introduces tiny particles into the sky to induce rain over small geographical areas, has gained popularity worldwide as a way to combat drought and increase local water supplies.

    But scientists say the technique cannot create weather—nor can it trigger rainfall at the scale observed in countries such as Germany and the United States.

    "Due to the strong natural variability of clouds, there exists very little scientific proof that cloud seeding has indeed a measurable effect on precipitation, say the experts.

    Experts emphasize that  climate change doubled the likelihood of floods in southern Brazil and worsened the intense rains caused by El Niño.

    There's definitely a consensus that climate change is responsible for many of these extreme weather events.

    And there is no definitive large-scale or long-term impacts from cloud seeding. We are already manipulating the weather at a global scale (larger) than would ever be possible through cloud seeding, scientists warn.

    Sours: AFP and other news agencies.

    **

  • Dr. Krishna Kumari Challa

    Tattoos Linked to Increased Cancer Risk, Scientists Warn

    Regret was for many years considered the most severe side-effect of tattoos. But a new study suggests there could be much worse things to worry about than that.

    Tattoos are now a mainstream means to express identity or celebrate milestones in life. Yet we know very little about the long-term health effects. Hazardous chemicals in tattoo ink have received attention during the last ten years. In parallel, research has shown that the ink that is injected into the skin does not stay there.

    The body perceives tattoo ink as something foreign that needs to be removed, and tattooing causes an immune response that results in a large fraction of ink particles ending up in the lymph nodes. But the last piece of the puzzle has been lacking: how does tattoo ink deposited in the lymphatic system affect people's health?

    To connect the dots, researchers conducted a large study to answer whether having tattoos might increase the risk of malignant lymphoma, a rare form of cancer that affects the white blood cells (lymphocytes). The study was recently published in the journal eClinicalMedicine.

    Scientists found that tattooed people had a 21% higher risk of lymphoma than people without tattoos after factoring in smoking status and education level (both being factors that may be associated with getting a tattoo and developing lymphoma).

    The size of the tattoos did not seem to matter. What did matter was time – how long participants had had their tattoos. The risk seemed to be higher for new tattoos (received within two years) and for older tattoos (received more than ten years ago).

    https://www.thelancet.com/journals/eclinm/article/PIIS2589-5370(24)00228-1/fulltext

  • Dr. Krishna Kumari Challa

    African savannah elephants call one another by ‘name’

    Elephants call out to each other using individual names that they invent for their fellow pachyderms, according to a recent study.

    While dolphins and parrots have been observed addressing each other by mimicking the sound of others from their species, elephants are the first non-human animals known to use names that do not involve imitation, the researchers suggested.

    For the new study, a team of international researchers used an AI algorithm to analyse the calls of two wild herds of African savannah elephants in Kenya.

    The research not only shows that elephants use specific vocalisations for each individual, but that they recognise and react to a call addressed to them while ignoring those addressed to others.

    This indicates that elephants can determine whether a call was intended for them just by hearing the call, even when out of its original context.

    The researchers sifted through elephant "rumbles" recorded at Kenya's Samburu National Reserve and Amboseli National Park between 1986 and 2022.

    Using a machine learning algorithm, they identified 469 distinct calls, which included 101 elephants issuing a call and 117 receiving one.

    Elephants make a wide range of sounds, from loud trumpeting to rumbles so low they cannot be heard by the human ear.

    Names were not always used in the elephant calls. But when names were called out, it was often over a long distance, and when adults were addressing young elephants.

    Adults were also more likely to use names than calves, suggesting it could take years to learn this particular talent.

    The most common call was "a harmonically rich, low-frequency sound”.

    This suggests that elephants and humans are the only two animals known to invent "arbitrary" names for each other, rather than merely copying the sound of the recipient.

    The evidence provided here that elephants use non-imitative sounds to label others indicates they have the ability for abstract thought.

    African savannah elephants call one another by ‘name’ - Nature Ecology & Evolution
    Using a combination of machine learning and playback experiments in the field, we find that African savannah elephants address members of their family with individually specific, name-like calls. These ‘names’ are probably not imitative of the receiver’s calls, which is similar to human naming but unlike known phenomena in other animals.
    https://www.nature.com/articles/s41559-024-02430-8

  • Dr. Krishna Kumari Challa

    A  robot that can autonomously remove weeds

    Robotic systems are already being deployed in various settings worldwide, assisting humans with a highly diverse range of tasks. One sector in which robots could prove particularly advantageous is agriculture, where they could complete demanding manual tasks faster and more efficiently.

    Among the many agricultural tasks that robots could tackle is the removal of weeds, which can cause significant damage to both livestock and crop farming. In fact, fast-growing and invasive weeds can both reduce the yield of crops and potentially poison animals, including horses, sheep, and cows.

    Researchers recently developed a new robot that can autonomously remove an invasive weed known as Rumex longifolius, or longleaf dock, which are highly rich in oxalates, compounds that can be poisonous to some livestock. Their robot, introduced in a paper pre-published on arXiv.

    Jarkko Kotaniemi et al, A Weeding Robot for Seedling Removal, arXiv (2024). DOI: 10.48550/arxiv.2405.12596

  • Dr. Krishna Kumari Challa

    Scientists reconstruct ancient genomes of the two most deadly malaria parasites to identify origin and spread

    In a study appearing in Nature, an international team of researchers reconstructed the evolutionary history and global spread of malaria over the past 5,500 years, identifying trade, warfare, and colonialism as major catalysts for its dispersal.

    Malaria, one of the world's deadliest infectious diseases, is caused by several species of single-celled parasites that are transmitted via the bite of infected Anopheles mosquitoes. Despite major control and eradication efforts, nearly half of the world's population still lives in regions where they are at risk of contracting malaria, and the World Health Organization estimates that malaria causes nearly 250 million infections and more than 600,000 deaths each year.

    Beyond this massive modern impact, malaria has strongly shaped our human evolutionary history.

    Although largely a tropical disease today, only a century ago the pathogen's range covered half the world's land surface, including parts of the northern U.S., southern Canada, Scandinavia, and Siberia.

    Malaria's legacy is written in our very genomes: genetic variants responsible for devastating blood disorders such as sickle cell disease are thought to persist in human populations because they confer partial resistance to malaria infection.

    Despite this evolutionary impact, the origins and spread of the two deadliest species of malaria parasites, Plasmodium falciparum and Plasmodium vivax, remain shrouded in mystery.

    Malaria infections leave no clear visible traces in human skeletal remains, and scant references in historical texts can be difficult to decipher. However, recent advances in the ancient DNA field have revealed that human teeth can preserve traces of pathogens present in a person's blood at the time of death, providing an opportunity to study illnesses that are normally invisible in the archaeological record.

    Part 1

  • Dr. Krishna Kumari Challa

    To explore malaria's enigmatic history, an international team of researchers representing 80 institutions and 21 countries reconstructed ancient Plasmodium genome-wide data from 36 malaria-infected individuals spanning 5,500 years of human history on five continents.

    These ancient malaria cases provide an unprecedented opportunity to reconstruct the worldwide spread of malaria and its historical impact at global, regional, and even individual scales.

    To track the parasites' journey into the Americas, the team analyzed ancient DNA from a malaria-infected individual from Laguna de los Cóndores, a high-altitude site situated in the remote cloud forests of the eastern Peruvian Andes.

    Genomic analysis revealed remarkable similarity between the Laguna de los Cóndores P. vivax strain and ancient European P. vivax, strongly suggesting that European colonizers spread this species to the Americas within the first century or so after contact.

    Amplified by the effects of warfare, enslavement, and population displacement, infectious diseases, including malaria, devastated Indigenous peoples of the Americas during the colonial period, with mortality rates as high as 90% in some places.
    Part 2

  • Dr. Krishna Kumari Challa

    Remarkably, the team also uncovered genetic links between the Laguna de los Cóndores strain and modern Peruvian P. vivax populations 400 to 500 years later.In addition to showing that malaria spread rapidly into what is a relatively remote region today, the  data suggest that the pathogen thrived there, establishing an endemic focus and giving rise to parasites that are still infecting people in Peru today.While the role of colonialism in the spread of malaria is evident in the Americas, the team uncovered military activities that shaped the regional spread of malaria on the other side of the Atlantic.
    The researchers  also identified several individuals infected with P. falciparum, a species that thrived in Mediterranean climates before eradication but was not thought to be endemic north of the Alps during this period.These virulent cases were found in non-local male individuals of diverse Mediterranean origins, who were likely soldiers recruited from northern Italy, Spain, and other Mediterranean regions to fight in the Hapsburg Army of Flanders during the 80 Years' War.They find that the large-scale troop movements played an important role in the spread of malaria during this period, similar to cases of so-called airport malaria in temperate Europe today.In our globalized world, infected travelers carry Plasmodium parasites back to regions where malaria is now eradicated, and mosquitoes capable of transmitting these parasites can even lead to cases of ongoing local transmission. Although the landscape of malaria infection in Europe is radically different today than it was 500 years ago, scientists see parallels in the ways in which human mobility shapes malaria risk.
    Part 3

  • Dr. Krishna Kumari Challa

    On the other side of the world, the team unexpectedly identified the earliest known case of P. falciparum malaria at the high Himalayan site of Chokhopani (ca. 800 BCE), located along the Kali Gandaki River Valley in the Mustang District of Nepal. At 2800 meters above sea level, the site lies far outside the habitat range for both the malaria parasite and the Anopheles mosquito.
    Human genetic analysis revealed that the infected individual was a local male with genetic adaptations for life at high altitude. However, archaeological evidence at Chokhopani and other nearby sites suggests that these Himalayan populations were actively engaged in long-distance trade.Resarchersthink of these regions today as remote and inaccessible, but in fact the Kali Gandaki River Valley served as a kind of trans-Himalayan highway connecting people on the Tibetan Plateau with the Indian subcontinent.Copper artifacts recovered from Chokhopani's burial chambers prove that the ancient inhabitants of Mustang were part of larger exchange networks that included northern India, and you don't have to travel very far to reach the low-lying, poorly drained regions of the Nepalese and Indian Terai where malaria is endemic today.
    Today, the human experience of malaria is at a crossroads. Thanks to advances in mosquito control and concerted public health campaigns, malaria deaths reached an all-time low in the 2010s. However, the emergence of antimalarial drug-resistant parasites and insecticide-resistant vectors threatens to reverse decades of progress, while climate change and environmental destruction are making new regions vulnerable to malaria vector species. The team hopes that ancient DNA may provide an additional tool for understanding and even combating this public health threat."For the first time, scientists are able to explore the ancient diversity of parasites from regions like Europe, where malaria is now eradicated.They see how mobility and population displacement spread malaria in the past, just as modern globalization makes malaria-free countries and regions vulnerable to reintroduction today. We hope that studying ancient diseases like malaria will provide a new window into understanding these organisms that continue to shape the world we live in today.
    Megan Michel, Ancient Plasmodium genomes shed light on the history of human malaria, Nature (2024). DOI: 10.1038/s41586-024-07546-2. www.nature.com/articles/s41586-024-07546-2
    Part 4

    **

  • Dr. Krishna Kumari Challa

    Study confirms the rotation of Earth's inner core has slowed

     Scientists have proven that the Earth's inner core is backtracking—slowing down—in relation to the planet's surface, as shown in new research published in Nature.

    Movement of the inner core has been debated by the scientific community for two decades, with some research indicating that the inner core rotates faster than the planet's surface. The new study provides unambiguous evidence that the inner core began to decrease its speed around 2010, moving slower than the Earth's surface.

    The inner core is considered to be reversing and backtracking relative to the planet's surface due to moving slightly slower instead of faster than the Earth's mantle for the first time in approximately 40 years. Relative to its speed in previous decades, the inner core is slowing down.

    The inner core is a solid iron-nickel sphere surrounded by the liquid iron-nickel outer core. Roughly the size of the moon, the inner core sits more than 3,000 miles under our feet and presents a challenge to researchers: It can't be visited or viewed. Scientists must use the seismic waves of earthquakes to create renderings of the inner core's movement.

    In this study, the researchers compiled and analyzed seismic data recorded around the South Sandwich Islands from 121 repeating earthquakes that occurred between 1991 and 2023. They have also utilized data from twin Soviet nuclear tests between 1971 and 1974, as well as repeated French and American nuclear tests from other studies of the inner core.

    The inner core's slowing speed was caused by the churning of the liquid iron outer core that surrounds it, which generates Earth's magnetic field, as well as gravitational tugs from the dense regions of the overlying rocky mantle.

    The implications of this change in the inner core's movement for Earth's surface can only be speculated. The backtracking of the inner core may alter the length of a day by fractions of a second and we can't notice this clearly.

    Wei Wang et al, Inner core backtracking by seismic waveform change reversals, Nature (2024). DOI: 10.1038/s41586-024-07536-4

  • Dr. Krishna Kumari Challa

    Scientists engineer human antibodies that could neutralize black widow toxin

    There are various types of widow spiders, including black, red, and brown varieties in North and South America, the Australian redback spider, and several button spider species that inhabit South Africa. In Europe, Latrodectus tredecimguttatus—the European black widow—inhabits the Mediterranean region, but recently and due to the changing climate, the widows have been expanding their habitat.

    Widow spiders' bites can cause latrodectism, a disease where the spider's venom, a neurotoxin known as alpha-latrotoxin, attacks the nervous system and causes symptoms like severe pain, hypertension, headache, and nausea. Black widow bites can be treated with antibodies derived from horses, but to make treatment safer for patients, researchers have set out to develop fully human antibodies.

    For the first time, they presented human antibodies which show neutralization of black widow spider venom in a cell-based assay. This is the first step to replace the horse sera that are still used to treat the severe symptoms after a black widow spider bite.

    Many patients bitten by black widows aren't treated altogether because the antivenom is made from proteins derived from horses which are foreign to the human body and can cause undesirable side effects. These include serum sickness, a reaction to proteins in antisera derived from non-human animal sources, and serious allergic reaction. The available antivenom is also an undefined mix of antibodies that varies from batch to batch. Despite these shortcomings, this antivenom is the most efficient treatment option available right now.

    Scientists set out to replace horse sera with recombinant human antibodies to get a better product for the patients and to avoid the use of horses for serum production. 

    To do so, the scientists used an in vitro method called antibody phage display.

    This approach uses extremely diverse gene collections of more than 10 billion different antibodies. From this large diversity of antibodies, phage display can fish out antibodies which can bind the desired target, in this case the toxin.

    Antibodies engineered in such a way can be reproduced in the same quality again and again because the DNA sequence of the human antibody is known. They also could also improve animal welfare because horses do not need to be immunized and bled to produce black window anti-toxins.

    Human antibodies neutralizing the alpha-latrotoxin of the European black widow, Frontiers in Immunology (2024). DOI: 10.3389/fimmu.2024.1407398

  • Dr. Krishna Kumari Challa

    New theory describes how waves carry information from surroundings

    Waves pick up information from their environment through which they propagate. A theory of information carried by waves has now been developed at TU Wien—with astonishing results that can be utilized for technical applications.

    Ultrasound is used to analyze the body, radar systems to study airspace or seismic waves to study the interior of our planet. Many areas of research are dealing with waves that are deflected, scattered or reflected by their surroundings. As a result, these waves carry a certain amount of information about their environment, and this information must then be extracted as comprehensively and precisely as possible.

    Searching for the best way to do this has been the subject of research around the world for many years. Researchers have now succeeded in describing the information carried by a wave about its environment with mathematical precision. This has made it possible to show how waves pick up information about an object and then transport it to a measuring device.

    This can now be used to generate customized waves to extract the maximum amount of information from the environment—for more precise imaging processes, for example. This theory was confirmed with microwave experiments. The results were published in the journal Nature Physics.

    Jakob Hüpfl et al, Continuity equation for the flow of Fisher information in wave scattering, Nature Physics (2024). DOI: 10.1038/s41567-024-02519-8

  • Dr. Krishna Kumari Challa

    How spaceflight disrupts a person’s biology
    Just a few days in orbit can cause immune-cell disruption, dehydration and cloudy thinking — but most of these conditions revert to normal soon after travellers return to Earth, according to the largest catalogue of data detailing the impacts of space travel on the human body. The reports aim to chart how spaceflight affects space tourists, who have a wider variety of health histories than trained astronauts. This is the beginning of precision medicine for spaceflight.

    https://www.nature.com/articles/s41586-024-07639-y.epdf?sharing_tok...

    https://www.nature.com/articles/s41586-024-07648-x.epdf?sharing_tok...

    **

  • Dr. Krishna Kumari Challa

    A glass that builds and heals itself

  • Dr. Krishna Kumari Challa

    A glass that builds and heals itself

  • Dr. Krishna Kumari Challa

    Drug that ‘melts away’ tumours hailed as ‘gamechanger’ for some bowel cancer patients
    Pembrolizumab triples chance of survival for the 10-15% of patients with the 'right genetic makeup', study finds
    A “gamechanger” immunotherapy drug that “melts away” tumours dramatically increases the chances of curing some bowel cancers and may even replace the need for surgery, doctors have said.

    Pembrolizumab targets and blocks a specific protein on the surface of immune cells that then seek out and destroy cancer cells.

    Giving the drug before surgery instead of chemotherapy led to a huge increase in patients being declared cancer-free, a clinical trial found. The results were presented at the annual meeting of the American Society of Clinical Oncology (ASCO), the world’s largest cancer conference.

    https://meetings.asco.org/abstracts-presentations/234190?utm_source...

  • Dr. Krishna Kumari Challa

    Imaging techniques peek into the placenta
    Researchers are finding ways to monitor an understudied human organ: the placenta. Defects in the placenta might be responsible for many miscarriages and stillbirths. The mysterious organ has proven difficult to study, largely because of the risks to pregnant women and their historical exclusion from clinical trials. Magnetic resonance imaging and ultrasounds help researchers to visualize the placenta and its blood flow in a non-invasive way, and spot potential problems before they lead to pregnancy loss. But progress remains slow. We’re dealing with a paradigm change, and there’s a lot of resistance to changing the paradigm now.  

    https://www.theatlantic.com/health/archive/2024/06/placenta-stillbi...

  • Dr. Krishna Kumari Challa

    Chronic Insomnia Linked to Ultra-Processed Foods

    Ultra-processed foods (UPFs) have been linked to health problems such as heart disease and diabetes, and a new study suggests they might also be contributing to chronic insomnia in some people. These UPFs can be any foodstuffs that are heavily modified to improve their taste, or produce them on a mass scale, or help them to last longer. They contrast with foods like fruit or vegetables, that come mostly as they are.

    Researchers led by a team from Sorbonne Paris Nord University in France looked at data collected on 38,570 adults as part of the NutriNet-Santé research project, mapping diet information against sleep variables.
    Researchers found a statistically significant association between higher UPF consumption and increased chronic insomnia risk, after allowances were made for sociodemographic, lifestyle, diet quality, and mental health factors.
    Overall, the study participants got 16 percent of their daily energy from UPFs, while 19.4 percent of the cohort reported symptoms of chronic insomnia – and this group tended to have more UPFs in their dietary intake.

    The data also showed a slightly stronger association in men. The study only assessed single points in time, and relied on self reporting, but the large number of people involved suggests this is a link that's worthy of future investigation.
    https://www.jandonline.org/article/S2212-2672(24)00094-7/fulltext