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

    Genesis of blue lightning into the stratosphere detected from ISS

    We know that there are many things left to discover, such as blue jets, elves and red sprites. These bizarre-sounding things are very difficult to observe from the surface of the Earth. As a new Nature paper reports, however, the European Atmosphere-Space Interactions Monitor (ASIM) observatory on the International Space Station is helping scientists find answers.

    Looking down on Earth's weather from the International Space Station 400 km above, ASIM's enhanced perspective is shedding new light on weather phenomena and their characteristics.

    The collection of optical cameras, photometers and an X- and gamma-ray detector was installed on the Space Station in 2018. It is designed to look for electrical discharges originating in stormy weather conditions that extend above thunderstorms into the upper atmosphere.

    And now, for the first time for an ESA International Space Station experiment, ASIM's findings have been published in Nature as front-page article. The paper describes a sighting of five intense blue flashes in a cloud top, one generating a 'blue jet' into the stratosphere.

    A blue jet is a form of lightning that shoots upwards from thunderstorm clouds. They can reach as far 50 km into the stratosphere and last less than a second. The space storm-hunter measured a blue jet that was kicked off with and intense five 10-microsecond flash in a cloud near the island of Naru in the Pacific Ocean.

    The flash also generated equally fantastic-sounding 'elves'. Elves are rapidly expanding rings of optical and UV emissions at the bottom of the ionosphere. Here, electrons, radio waves and the atmosphere interact to form these emissions.

    Capturing these phenomena using ASIM's highly sensitive tools is vital for scientists researching weather systems on Earth.

     Observation of the onset of a blue jet into the stratosphere, Nature (2021). DOI: 10.1038/s41586-020-03122-6 , www.nature.com/articles/s41586-020-03122-6

    https://phys.org/news/2021-01-genesis-blue-lightning-stratosphere-i...

  • Dr. Krishna Kumari Challa

    New antifungal compound from ant farms

    Attine ants are farmers, and they grow fungus as food. Pseudonocardia and Streptomyces bacteria are their farmhands, producing metabolites that protect the crop from pathogens. Surprisingly, these metabolites lack common structural features across bacteria from different geographic locations, even though the ants share a common ancestor. Now, researchers report in ACS Central Science they have identified the first shared antifungal compound among many of these bacteria across Brazil. The compound could someday have medical applications.

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    When a story is breaking, AI can help consumers identify fake news

    Warnings about misinformation are now regularly posted on Twitter, Facebook, and other social media platforms, but not all of these cautions are created equal. New research from Rensselaer Polytechnic Institute shows that artificial intelligence can help form accurate news assessments—but only when a news story is first emerging.

  • Dr. Krishna Kumari Challa

    Some COVID-19 mutations may dampen vaccine effectiveness

    Scientists are reporting troubling signs that some recent mutations of the virus that causes COVID-19 may modestly curb the effectiveness of two current vaccines, although they stress that the shots still protect against the disease.

    Researchers expressed concern Wednesday about the preliminary findings, in large part because they suggest that future mutations could undermine vaccines. The research tested coronaviruses from the United Kingdom, South Africa and Brazil, and was led by Rockefeller University in New York with scientists from the National Institutes of Health and elsewhere.

    A different, more limited study out Wednesday gave encouraging news about one vaccine's protection against some of the mutations.

    One way vaccines work is to prompt the immune system to make antibodies that block the virus from infecting cells. The Rockefeller researchers got blood samples from 20 people who had received either the Moderna or Pfizer vaccine and tested their antibodies against various virus mutations in the lab.

    With some, the antibodies didn't work as well against the virus—activity was one-to-threefold less, depending on the mutation.

    It's a small difference but it is definitely a difference. The antibody response is "not as good" at blocking the virus.

    Earlier research established that the two vaccines are about 95% effective in preventing COVID-19 illness.

    The latest findings were posted late Tuesday on an online website for researchers 

    https://medicalxpress.com/news/2021-01-covid-mutations-dampen-vacci...

  • Dr. Krishna Kumari Challa

    Some COVID-19 mutations may dampen vaccine effectiveness

    Scientists are reporting troubling signs that some recent mutations of the virus that causes COVID-19 may modestly curb the effectiveness of two current vaccines, although they stress that the shots still protect against the disease.

    Researchers expressed concern Wednesday about the preliminary findings, in large part because they suggest that future mutations could undermine vaccines.

    A different, more limited study out Wednesday gave encouraging news about one vaccine's protection against some of the mutations.

    One way vaccines work is to prompt the immune system to make antibodies that block the virus from infecting cells. The Rockefeller researchers got blood samples from 20 people who had received either the Moderna or Pfizer vaccine and tested their antibodies against various virus mutations in the lab.

    With some, the antibodies didn't work as well against the virus—activity was one-to-threefold less, depending on the mutation. It's a small difference but it is definitely a difference. The antibody response is "not as good" at blocking the virus.

    Earlier research established that the two vaccines are about 95% effective in preventing COVID-19 illness.

    The latest findings were posted late Tuesday on an online website for researchers.

    We don't want people thinking that the current vaccine is already outdated. That's absolutely not true. There's still immunity here ... a good level of protection but the mutations "do in fact reduce how well our immune response is recognizing the virus."

    We've got an arms race between the vaccines and the virus. The slower we roll out vaccine around the world, the more opportunities we give this virus to escape" and develop mutations

    https://www.biorxiv.org/content/10.1101/2021.01.15.426911v1

    https://medicalxpress.com/news/2021-01-covid-mutations-dampen-vacci...

  • Dr. Krishna Kumari Challa

    Antibiotic resistance may spread even more easily than expected

    Pathogenic bacteria in humans are developing resistance to antibiotics much faster than expected. Now, computational research shows that one reason could be significant genetic transfer between bacteria in our ecosystems and to humans. This work has also led to new tools for resistance researchers.

    Completely different species of bacteria can spread resistance genes to each other through plasmids—small DNA molecules where bacteria store some of their genes outside the chromosome. When two bacterial cells come into contact, they can copy plasmids to each other. This is called conjugation, and it is the most important mechanism for spreading antibiotic resistance.

    In recent years, we've seen that resistance genes spread to human pathogens to a much greater degree than anyone expected.

    Many of the genes appear to have originated in a wide array of bacterial species and environments, such as soil, water and plant bacteria. This has been difficult to explain, because although conjugation is very common, we've thought that there was a distinct limitation for which bacterial species can transfer plasmids to each other. Plasmids belong to different mobility groups, or MOB groups, so they can't transfer between just any bacterial species.

    The results show, among other things, that:

    • The number of oriT regions may be almost eight times higher than those found with the standard method used today.
    • The number of mobile plasmids may be twice as high as previously known.
    • The number of bacterial species that have mobile plasmids may be almost twice as high as previously known.
    • Over half of these plasmids have oriT regions that match a conjugation enzyme from another plasmid that has previously been classified in a different MOB group. This means that they could be transferred by one of these plasmids that happens to be in the same bacterial cell.

    The last part means that there may be transfer mechanisms between large numbers of bacterial species and environments where we previously believed there were barriers.

    Jan Zrimec, Multiple plasmid origin‐of‐transfer regions might aid the spread of antimicrobial resistance to human pathogens, MicrobiologyOpen (2020). DOI: 10.1002/mbo3.1129

    https://phys.org/news/2021-01-antibiotic-resistance-easily.html?utm...

  • Dr. Krishna Kumari Challa

    Cancer can be precisely diagnosed using a urine test with artificia...

    Prostate cancer is one of the most common cancers among men. Patients are determined to have prostate cancer primarily based on PSA, a cancer factor in blood. However, as diagnostic accuracy is as low as 30%, a considerable number of patients undergo additional invasive biopsy and thus suffer from resultant side effects, such as bleeding and pain.

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    Scientists shine new light on heat-damaged hair

    A new technique allowed researchers to observe in greater detail how heat alters keratin proteins, helping in their search for ingredients that can prevent heat-damaged hair.

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    As more bacteria grow resistant to antibiotics, scientists are figh...

    Scottish bacteriologist Alexander Fleming's discovery of penicillin, the world's first antibiotic, saved countless lives. But even as the bacteria killer first hit the U.S. market—in the closing months of World War II—Fleming warned the world about what penicillin might unleash.

  • Dr. Krishna Kumari Challa

    Bubble micro-robots!

    Lasers create miniature robots from bubbles

  • Dr. Krishna Kumari Challa

    Sci-COM : Storytelling can be a powerful tool for science

    Credible science communication and storytelling are not mutually exclusive — they can be great allies.

    In contrast with straight communication of experimental results, telling individual research stories portrays science as a human-driven endeavour, full of successes, uncertainties, missteps and failures, which in turn promotes transparency. What really matters is what story is being told and by whom.

    https://www.nature.com/articles/d41586-021-00108-w?utm_source=Natur...

  • Dr. Krishna Kumari Challa

    S. Africa virus strain poses 're-infection risk': study

    The coronavirus variant detected in South Africa poses a "significant re-infection risk" and raises concerns over vaccine effectiveness, according to preliminary research Wednesday, as separate studies suggested the British strain would likely be constrained by immunisations. Several new variants -- each with a cluster of genetic mutations -- have emerged in recent weeks, sparking fears over an increase in infectiousness as well as suggestions that the virus could begin to elude immune response, whether from prior infection or a vaccine. These new variants, detected from Britain, South Africa and Brazil, have mutations to the virus' spike protein, which enables the virus to latch onto human cells and therefore plays a key role in driving infections. But it is one mutation in particular -- known as E484K and present in the variants detected in South Africa and Brazil but not the one from Britain -- that has experts particularly worried about immunity "escape".

    They found that it was resistant to neutralising antibodies built up from prior infection, but said more research was needed into the effectiveness of other parts of the immune response.

    The 501Y.V2 lineage, which contains nine spike mutations and rapidly emerged in South Africa during the second half of 2020, is largely resistant to neutralising antibodies elicited by infection with previously circulating lineages. This suggests that, despite the many people who have already been infected with SARS-CoV-2 globally and are presumed to have accumulated some level of immunity, new variants such as 501Y.V2 pose a significant re-infection risk.

    The researchers added that this might also affect the use of convalescent plasma as a treatment for Covid-19. They also suggested it could have "implications" for vaccines developed based on immune responses to the virus's spike protein.

    https://researchnews.cc/news/4730/S--Africa-virus-strain-poses--re-...

  • Dr. Krishna Kumari Challa

    Scientists solve a 100-year-old mystery about cancer

    In 1921, German physician Otto Warburg observed that cancer cells harvest energy from glucose sugar in a strangely inefficient manner: rather than "burn" it using oxygen, cancer cells do what yeast do—they ferment it. This oxygen-independent process occurs quickly, but leaves much of the energy in glucose untapped.  

    Various hypotheses to explain the Warburg effect have been proposed over the years, including the idea that cancer cells have defective mitochondria—their "energy factories"—and therefore cannot perform the controlled burning of glucose. But none of these explanations has withstood the test of time. (Cancer cells' mitochondria work just fine, for example.)
    Now a research team  offers a new answer, based on a hefty set of genetic and biochemical experiments and published January 21 in the journal Science.It comes down to a previously unappreciated link between Warburg metabolism and the activity of a powerhouse enzyme in the cell called PI3 kinase. PI3 kinase is a key signaling molecule that functions almost like a commander-in-chief of cell metabolism. Most of the energy-costly cellular events in cells, including cell division, occur only when PI3 kinase gives the cue. As cells shift to Warburg metabolism, the activity of PI3 kinase is increased, and in turn, the cells' commitment to divide is strengthened. It's a bit like giving the commander-in-chief a megaphone.The findings revise the commonly accepted view among biochemists that sees metabolism as secondary to cell signaling. They also suggest that targeting metabolism could be an effective way to thwart cancer growth.

    As with immune cells, cancer cells may employ Warburg metabolism as a way to sustain the activity of this signaling pathway and therefore ensure their continued growth and division.

    The results raise the intriguing possibility that doctors could curb cancer growth by blocking the activity of LDHA—the Warburg "switch."

     Ke Xu et al, Glycolysis fuels phosphoinositide 3-kinase signaling to bolster T cell immunity, Science (2021). DOI: 10.1126/science.abb2683

    https://medicalxpress.com/news/2021-01-scientists-year-old-mystery-...

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  • Dr. Krishna Kumari Challa

    MRI helps unravel the mysteries of sleep

      The state of consciousness changes significantly during stages of deep sleep, just as it does in a coma or under general anesthesia. Scientists have long thought, but couldn't be certain, that brain activity declines during sleep. Most research on sleep is conducted using electroencephalography (EEG), a method that entails measuring brain activity through electrodes placed along a patient's scalp. However researchers now  investigated brain activity during sleep using magnetic resonance imaging (MRI).  
      MRI scans measure neural activity by detecting the hemodynamic response of structures throughout the brain, thereby providing important information in addition to EEGs.  During these experiments, researchers relied upon EEG to identify when the study participants had fallen asleep and pinpoint the different stages of sleep. Then they examined the MRI images to generate spatial maps of neural activity and determine different brain states. 
    The brain activity data were recorded over a period of nearly two hours while participants were sleeping in an MRI machine. 
      After checking, analyzing and comparing all the data, what they found was surprising. They calculated exactly how many times networks made up of different parts of the brain became active during each stage of sleep and discovered that during light stages of sleep—that is, between when you fall asleep and when you enter a state of deep sleep—overall, brain activity decreases. But communication among different parts of the brain becomes much more dynamic - that's due to the instability of brain states during this phase. 
      What 's really surprising  in all this was the resulting paradox. During the transition phase from light to deep sleep, local brain activity increased and mutual interaction decreased. This indicates the inability of brain networks to synchronize.  
     Consciousness is generally associated with neural networks that may be linked to our introspection processes, episodic memory and spontaneous thought.   
    Researchers  observed that the network between the anterior and posterior regions broke down, and this became increasingly pronounced with increasing sleep depth. A similar breakdown in neural networks was also seen in the cerebellum, which is typically associated with motor control.
    These  findings are a first step toward a better understanding of states of consciousness during sleep. They show that consciousness is the result of interactions between different brain regions, and not in localized brain activity.
      By studying how our state of consciousness is altered during different stages of sleep, and what that means in terms of brain network activity, we can better understand and account for the wide range of brain functions that characterize us as human beings.  
    Anjali Tarun et al, NREM sleep stages specifically alter dynamical integration of large-scale brain networks, iScience (2020). DOI: 10.1016/j.isci.2020.101923
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  • Dr. Krishna Kumari Challa

    Combined river flows could send up to 3 billion microplastics a day into the Bay of Bengal

    The Ganges River—with the combined flows of the Brahmaputra and Meghna rivers—could be responsible for up to 3 billion microplastic particles entering the Bay of Bengal every day, according to new research.

    The study represents the first investigation of microplastic abundance, characteristics and seasonal variation along the river and was conducted using samples collected by an international team of scientists as part of the National Geographic Society's Sea to Source: Ganges expedition.

    Over two expeditions in 2019, 120 samples (60 each in pre- and post-monsoon conditions) were gathered at 10 sites by pumping river water through a mesh filter to capture any particles.

    The samples were then analysed in laboratories at the University of Plymouth with microplastics found in 43 (71.6%) of the samples taken pre-monsoon, and 37 (61.6%) post-monsoon.

    More than 90% of the microplastics found were fibres and, among them, rayon (54%) and acrylic (24%) - both of which are commonly used in clothing—were the most abundant.

    Combining predicted microplastic concentration at the mouth of the river (Bhola, Bangladesh) with the discharge of the river, scientists estimate that between 1 billion and 3 billion microplastics might be being released from the Ganges Brahmaputra Meghna River Basin every day.

    Imogen E. Napper et al, The abundance and characteristics of microplastics in surface water in the transboundary Ganges River, Environmental Pollution (2021). DOI: 10.1016/j.envpol.2020.116348

    https://phys.org/news/2021-01-combined-river-billion-microplastics-...

  • Dr. Krishna Kumari Challa

    How Do Bacteria Become Resistant to Antibiotics?

  • Dr. Krishna Kumari Challa

    Blue Monday claims are 'pseudo-scientific gibberish, nonsense' - Consultant psychologist

    https://www.newstalk.com/news/blue-monday-claims-are-pseudo-scienti...

    Those who claim third Monday of Jan., (Blue Monday is the name given to a day in January (typically the third Monday of the month) said by a UK travel company, Sky Travel, to be the most depressing day of the year. The concept was first published in a 2005 press release from the company, which claimed to have calculated the date using an "equation") marks the most depressing day of the year are spouting “pseudo-scientific gibberish,” according to a consultant clinical psychologist.

    Over recent years, the third Monday in January has become known as ‘Blue Monday’ – with people struggling to come to terms with long nights, the weather, money problems and unfulfilled resolutions.

    Saying that the most depressing thing about Blue Monday is that this pseudo-science, gibberish, nonsense has not been forgotten about and we are still talking about it. It is not a thing. It was invented in 2005 by an advertising company to help a travel company sell holidays; to let us know that we need to book our holidays long in advance. They came up with this gibberish formula that does nothing except make us feel worse about ourselves.

    If you look around and see the environment we have right now, we have enough things to be sad and anxious about. We don’t need this on top of everything else. There is zero scientific evidence behind the claims and experts warned of a real danger that it could “become a self-fulfilling prophecy” for people as long as it continues.

    People go into it thinking, ‘this is going to be the saddest day of the year’ and in that day then they feel sad because they feel they are supposed to be sad. But no, it isn’t. It is just a day like any other.

    People who are feeling down or depressed need support every day of the year, not on “some random day that was picked by an advertising company.” It is completely invalidating to those who are suffering from depression.

    It is as useful as getting out the horoscope to predict how the day is going to go. People struggle day in, day out – not on any one given day or because of a date.

  • Dr. Krishna Kumari Challa

    Evolution doesn’t work the way you think it does

    An evolutionary biologist explains all the things you might get into an argument over

    https://massivesci.com/articles/evolution-darwin-fitness-genes-sele...

    https://massivesci.com/articles/evolution-darwin-fitness-genes-sele...

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    'Male' vs 'female' brains: having a mix of both is common and offers big advantages – new research
    While there are small differences between male and female brains, most of us have a mix of both.
  • Dr. Krishna Kumari Challa

    Lilly antibody reduced Covid-19 risk by 80% in nursing home study

    A synthetic antibody developed by Eli Lilly reduced the risk of contracting Covid-19 by 80 percent in a study of nursing home residents when used preventatively, the company said Thursday. Though the result is only preliminary and awaiting peer review, the finding was hailed as highly promising by experts, who said it meant that the infused therapy had the potential to complement vaccines. "We are exceptionally pleased with these positive results, which showed bamlanivimab was able to help prevent COVID-19, substantially reducing symptomatic disease among nursing home residents, some of the most vulnerable members of our society.

    The result came from a late-stage clinical trial sponsored by the US government that examined 299 residents and 666 staff of long-term care facilities who tested negative for the virus.

    The result came from a late-stage clinical trial sponsored by the US government that examined 299 residents and 666 staff of long-term care facilities who tested negative for the virus, the company said in a press release.

    The participants were randomly assigned either 4.2 grams of bamlanivimab, or a placebo.

    After eight weeks of follow-up, the risk of developing symptomatic Covid-19 was overall reduced by 57 percent for those receiving the treatment.

    In particular, residents on bamlanivimab had a 80 percent lower risk of contracting the disease.

    Among the 299 residents, there were four deaths attributed to Covid-19, all in the placebo arm.

    https://researchnews.cc/news/4768/Lilly-antibody-reduced-Covid-19-r...

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  • Dr. Krishna Kumari Challa

    Spitting cobra venoms evolved to cause extreme pain.

  • Dr. Krishna Kumari Challa

    Airflows inside passenger cars and implications for airborne disease transmission  

    How to Have a COVID-Safe Car Ride, According to Science
    Sharing a car with someone is one of the riskiest things you can do without cohabitating, as far as coronavirus transmission goes.

    While taking a car may feel like a slightly safer alternative compared to public transportation, it's still a small, enclosed space. Even if all passengers are wearing masks, some small particles can escape from the face coverings into the air.

    It's usually not significant when you're outdoors, because it gets diluted.   But when you're in a confined space like that of a car, if [the particles] are not flushed out of the cabin, they can remain and build up a concentration with time.

    Scientists been modelling how particles may move inside vehicles with various levels of ventilation using fluid mechanics.

    These things were found in various simulations:

    Rolling down all of the windows was the most effective way to clear out potentiallyvirus-laden particles from a car.  When all windows were closed, 8 percent to 10 percent of the tiny particles one person exhaled could reach another. That number dropped to 0.2 percent to 2 percent when all four windows were open.

    But on a chilly winter day, opening all of the windows may not be the most practical option, so the authors experimented with alternatives, and came up with some suggestions.

    If you're going to open two windows, pick the ones opposite the driver and passenger
    The simulated car was based on a Toyota Prius driving at 50 miles per hour, with a driver in the front left seat and a single passenger in the back right. While a passenger may intuitively crack the window closest to them upon getting in a car, opening the windows opposite the driver (front right) and passenger (back left) provided better ventilation in the model.

    In a moving car, fresh air typically flows in through the rear window and out the front window .  Opening the windows opposite the occupants not only provides an entry and exit point for particles, but also creates a current of air separating the passenger from the driver.

    However, the difference between the two-windows-open configurations they tested was "marginal."

    You should open some windows at least halfway if you're sharing a car, and always wear a mask
    Opening car windows is not a foolproof way to avoid coronavirus transmission. Sharing a car with someone outside of your household is a risky move, and opening windows is one way to reduce that risk. But that extra ventilation is not a substitute for other prevention measures, such as mask-wearing, handwashing, and sanitizing common surfaces.

    Plastic barriers between driver and passenger could help stop droplets. While such sheets are not a substitute for fresh air, it doesn't hurt to have them. 
    The barriers are helpful in preventing all kinds of droplet transmission, including the small ones .
     But a better way is to also have a ventilation system, so that the air inside the cabin gets replenished with fresh air from the outside.

  • Dr. Krishna Kumari Challa

    Visual Behavior Modeling for Robotic Theory of Mind

  • Dr. Krishna Kumari Challa

    The Blanket Octopus and it's AMAZING Blanket!!

  • Dr. Krishna Kumari Challa

    Exciting Study on Mouse Immune Cells Reveals How We Might Reverse Cognitive Decline in old age

    New research hints at a cause – and possible solution – for some of the ailments and decline that often come with age.

    Scientists have long known that cognitive decline as we get older and specific age-related diseases including Alzheimer's  are linked to inflammation, but they are still uncovering precisely why and how this is the case. 

    Research published Wednesday in the journal Nature pinpoints the role of a messenger hormone found in much higher levels in older people, and mice, than their younger counterparts.

    When the hormone was blocked in older mice, they were able to perform as well as more youthful rodents in tests of their memory and navigation.

    The researchers found that higher levels of the hormone affected the metabolism of immune cells called macrophages, prompting them to store energy rather than consume it.

    That ends up effectively starving the cells and sends them into a damaging inflammatory hyperdrive that contributes to age-related cognitive decline and several age-related diseases.

    The hormone, prostaglandin E2 (PGE2), "is a major regulator of all types of inflammation, both good and bad, and its effect depends on the receptor that is activated. This new study identified the EP2 receptor... as the receptor that leads to energy depletion and maladaptive inflammation.

    Older mice that received the compounds or had the receptor deleted from their genes performed as well as young mice when tested for navigation and spatial memory, both of which deteriorate with ageing and diseases like Alzheimer's.

    https://www.nature.com/articles/s41586-020-03160-0

    https://www.sciencealert.com/a-study-on-mice-immune-cells-reveals-a...

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    Researchers create new form of cultivated meat

    McMaster researchers have developed a new form of cultivated meat using a method that promises more natural flavor and texture than other alternatives to traditional meat from animals.

  • Dr. Krishna Kumari Challa

    Your Body Makes 3.8 Million Cells Every Second. Most of Them Are Blood

    Deep within, on a cellular scale, your body is in a constant state of activity to keep you alive. Among those processes is the turnover of cells, replacing the cells that die with fresh new ones so that you don't crumble to bits like a zombie.

    A new calculation reveals just how intensive that process is. According to biologists Ron Sender and Ron Milo of the Weizmann Institute of Science in Israel, your body replaces around 330 billion cells per day. At that rate, your body is making over 3.8 million new cells every second.

    Most of those are blood cells, followed by cells in your gut. Less than 2 percent of your cell turnover is everything else. Confirming these numbers could help scientists better understand how the human body functions and the role cell turnover plays in both health and disease.

    It's a common myth that your body completely regenerates all its cells every seven years. The reality is a lot more complicated. Some cells live just a few days, while others – such as neurons in the cerebellum and lipids in the lenses of your eyes – are limited only by the lifespan of the host (you). So humans are very far from a Ship of Theseus situation. However, while scientists have previously worked out estimates for how many cells are in the body, what kind they are, and what their lifespans are, very little work has been done to take a census of the cellular turnover rate.

    --

    They based their calculations on a standard reference person: a healthy male between the ages of 20 and 30, weighing 70 kilograms (154 pounds) and 170 centimetres (5 feet 7 inches) tall. Then, for their estimation of cell turnover rates, they included every cell type that constitutes over 0.1 percent of the total cell population.

    Cell lifespans were collected from a literature survey, using only those works that took direct measurements of the lifespans of human cells. Then they derived the overall cellular mass for each type, based on the average cell mass.

    Based on this information, the pair then calculated that their standard reference person would have a cell turnover rate of around 80 grams (2.8 ounces) per day, or 330 billion cells.

    Of that turnover by number, 86 percent would be blood cells, mostly erythrocytes (red blood cells, the most abundant cell type in the body) and neutrophils (the most abundant type of white blood cell). Another 12 percent would be gastrointestinal epithelial cells, with small amounts of skin cells (1.1 percent), endothelial cells that line the blood vessels, and lung cells (0.1 percent each).

    Although blood cells make up most of cell turnover in terms of individual cell count, by mass it's a different story. Only 48.6 percent of the mass is blood cells, of all types. Gastrointestinal cells make up another 41 percent. Skin cells make up 4 percent, while adipocytes, or fat cells, which barely registered in cell numbers, make up another 4 percent by mass.

    https://www.nature.com/articles/s41591-020-01182-9

    (If you're wondering what happens to all the dead cells, they either get sloughed off, in the case of skin and gastrointestinal cells, and sometimes slurped up by parasites, or broken down and partially recycled by the body. Waste not, want not!)

    https://www.sciencealert.com/your-body-makes-4-million-cells-a-seco...

  • Dr. Krishna Kumari Challa

    SARS-CoV-2 needs cholesterol to invade cells and form mega cells

    People taking cholesterol-lowering drugs may fare better than others if they catch the novel coronavirus. A new study hints at why: the virus relies on the fatty molecule to get past the cell's protective membrane.

    To cause COVID-19, the SARS-CoV-2 virus must force its way into people's cells—and it needs an accomplice. Cholesterol, the waxy compound better known for clogging arteries, helps the virus open cells up and slip inside.

    Without cholesterol, the virus cannot sneak past a cell's protectiv... and cause infection. Cholesterol is an integral part of the membranes that surround cells and some viruses, including SARS-CoV-2. It makes sense that it should be so important for infection. The finding might underlie the better health outcomes seen in COVID-19 patients taking cholesterol-lowering drugs known as statins.

    This discovery of cholesterol's importance could help scientists develop new stopgap measures to treat COVID-19 until most people are vaccinated.

    David W. Sanders et al. SARS-CoV-2 Requires Cholesterol for Viral Entry and Pathological Syncytia Formation, bioRxiv (2020). DOI: 10.1101/2020.12.14.422737

    https://phys.org/news/2021-01-sars-cov-cholesterol-invade-cells-meg...

    SARS-CoV-2 Needs Cholesterol to Invade Cells

  • Dr. Krishna Kumari Challa

    The mystery of the blue flower: nature’s rare colour owes its existence to bee vision

    https://theconversation.com/the-mystery-of-the-blue-flower-natures-...

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    Microbes fuelled by wind-blown mineral dust melt the Greenland ice ...

    Scientists have identified a key nutrient source used by algae living on melting ice surfaces linked to rising sea levels.The Greenland ice sheet—the second largest ice body in the world after the Antarctic ice sheet—covers almost 80% of the surface of Greenland. Over the last 25 years, surface melting and water runoff from the ice sheet has increased by about 40%.The international research team, led by the University of Leeds, analysed samples from the southwestern margin on Greenland's 1.7 million km2 ice sheet over two years.They discovered that phosphorus containing minerals may be driving ever-larger algal blooms on the Greenland Ice Sheet. As the algal blooms grow they darken the ice surface, decreasing albedo—the ability to reflect sunlight. The blooms cause increased melting thus contributing to higher sea levels. In particular, a band of low-albedo ice, known as the Dark Zone, has developed along the western margin of the massive ice sheet.

    --

    Puzzling six-exoplanet system with rhythmic movement challenges the...

    Using a combination of telescopes, including the Very Large Telescope of the European Southern Observatory (ESO's VLT), astronomers have revealed a system consisting of six exoplanets, five of which are locked in a rare rhythm around their central star. The researchers believe the system could provide important clues about how planets, including those in the Solar System, form and evolve.

  • Dr. Krishna Kumari Challa

    Study explores the effects of maternal inflammation on fetal brain development

    Research suggests that infections or inflammation in pregnant women can be linked with the development of neurodevelopmental disorders in their offspring. Inflammation during pregnancy (maternal immune activation, or MIA) disrupts fetal brain development and leads to abnormal behavior in offspring. While this association is well-documented, the molecular and neural mechanisms underpinning it are still poorly understood.

     Scientists have recently carried out a study aimed at better understanding how maternal immune activation (MIA) can influence the development of the fetus and potentially facilitate the occurrence of neurodevelopmental disorders. Their paper, published in Nature Neuroscience, shows that MIA can activate a particular neural pathway that regulates the translation of messenger RNA (mRNA) molecules in the brain of pre-natal male mice, disrupting a process known as proteostasis.

    The mRNA molecule is essentially a single-stranded molecule of RNA that puts DNA genetic instructions into action. Proteostasis (or protein homeostasis), on the other hand, is the process that regulates proteins within and around cells, maintaining their health and preventing their degradation.

    When scientists blocked the ISR, whether using transgenic mice (i.e., mice with genomes altered by humans) or drugs, they were able to reverse the behavioral deficits observed in MIA offspring. Moreover, in pre-natal male mice, blocking the ISR restored balance in cortical neural activity.

    Overall, this recent study unveiled specific alterations in protein homeostasis associated with maternal inflammation and occurring predominantly in pre-natal male mice, which could increase the risk of neurodevelopmental disorders in MIA-exposed offspring. In the future, the findings gathered by Kalish, Kim and their colleagues could inspire further research aimed at better understanding such immune-neural interaction, which could ultimately inform the development of strategies to reduce the adverse effects of MIA on the fetal brain.

    Maternal immune activation in mice disrupts proteostasis in the fetal brain. Nature Neuroscience(2021). DOI: 10.1038/s41593-020-00762-9.

    https://medicalxpress.com/news/2021-01-explores-effects-maternal-in...

    **

  • Dr. Krishna Kumari Challa

    Study proves potential for reducing pre-term birth by treating fetus as patient

    The results of a study by researchers at the University of Texas Medical Branch may pave the way for a new medicine delivery system that could reduce the incidence of pre-term labor and premature birth by allowing physicians to treat the 'fetus as the patient'. The study has been published in Science Advances.

    It has long been suspected that pre-term labor is triggered by inflammation caused by a sick fetus. A new study by scientists at UTMB has proved the hypothesis by studying several important assumptions about the relationship between the health of a mother and her unborn child.

    Researchers tested their bioengineered exosomes as a delivery system for anti-inflammatory medicine directly to the fetus. Exosomes are natural nanoparticles or vesicles in our bodies, and we have trillions of them circulating through us at all times. By packaging the medicine inside a bioengineered exosome and injecting it into the mother intravenously, the exosomes travel through the blood system, cross the placental barrier and arrive in the fetus, where they deliver the medicine.

    There were several steps prior to testing the drug delivery. First, Menon said it was important to prove that fetal cells, specifically immune cells, actually migrated through the mother's body to her uterine tissues as well as to her, which can cause inflammation, the leading cause of pre-term labor.

    To prove migration of cells, female mice were mated with male mice who had been genetically engineered with a red fluorescent dye called tdtomato. The dye causes cells in the male to turn red, so once mating has occurred, cells in the developing fetus also turn red and can easily be tracked as they migrate through the mother.

    Once scientists had proof of cell migration, they next used the mouse model to determine if bioengineered exosomes could deliver a special anti-inflammatory medicine, an inhibitor of NF-kB, called super repressor (SR) IkB from the mother's bloodstream to the fetus.

    the study found that:

    * Sustained effects/delays in labor required repeated dosing
    * Prolongation of gestation improved pup viability
    * Mouse models provided valuable information to help understand the mechanisms often seen in humans
    * Future studies, including human clinical trials are needed to confirm laboratory results

    Samantha Sheller-Miller et al, Exosomal delivery of NF-κB inhibitor delays LPS-induced preterm birth and modulates fetal immune cell profile in mouse models, Science Advances (2021). DOI: 10.1126/sciadv.abd3865

    https://medicalxpress.com/news/2021-01-potential-pre-term-birth-fet...

  • Dr. Krishna Kumari Challa

    Researchers guide a single ion through a Bose-Einstein condensate

    Physicists has now developed a new method to observe a single charged particle on its path through a dense cloud of ultracold atoms. The results were published in Physical Review Letters and are further reported in a Viewpoint column in the journal Physics.

    They used a Bose-Einstein condensate (BEC) for their experiments. This exotic state of matter consists of a dense cloud of ultracold atoms. By means of sophisticated laser excitation, the researchers created a single Rydberg atom within the gas. In this giant atom, the electron is a thousand times further away from the nucleus than in the ground state and thus only very weakly bound to the core. With a specially designed sequence of electric field pulses, the researchers snatched the electron away from the atom. The formerly neutral atom turned into a positively charged ion that remained nearly at rest despite the process of detaching the electron.

    In the next step, the researchers used precise electric fields to pull the ion in a controlled way through the dense cloud of atoms in the BEC. The ion picked up speed in the electric field, collided on its way with other atoms, slowed down and was accelerated again by the electric field. The interplay between acceleration and deceleration by collisions led to a constant motion of the ion through the BEC.

    This new approach allowed the researchers to measure the mobility of a single ion in a Bose-Einstein condensate for the very first time.

    T. Dieterle et al. Transport of a Single Cold Ion Immersed in a Bose-Einstein Condensate, Physical Review Letters (2021). DOI: 10.1103/PhysRevLett.126.033401

    https://phys.org/news/2021-01-ion-bose-einstein-condensate.html?utm...

  • Dr. Krishna Kumari Challa

    Optimal information about the invisible

    Laser beams can be used to precisely measure an object's position or velocity. Normally, however, a clear, unobstructed view of this object is required—and this prerequisite is not always satisfied. In biomedicine, for example, structures are examined, which are embedded in an irregular, complicated environment. There, the laser beam is deflected, scattered and refracted, often making it impossible to obtain useful data from the measurement.

    Researchers have now been able to show that meaningful results can be obtained even in such complicated environments. Indeed, there is a way to specifically modify the laser beamso that it delivers exactly the desired information in the complex, disordered environment—and not just approximately, but in a physically optimal way: Nature does not allow for more precision with coherent laser light. The new technology can be used in very different fields of application, even with different types of waves, and has now been presented in the scientific journal Nature Physics.

    Dorian Bouchet et al. Maximum information states for coherent scattering measurements, Nature Physics (2021). DOI: 10.1038/s41567-020-01137-4

    https://phys.org/news/2021-01-optimal-invisible.html?utm_source=nwl...

  • Dr. Krishna Kumari Challa

    Apple warns to keep iPhone 12, MagSafe accessories "safe distance" from medical devices

    Apple is warning owners of the iPhone 12 and any MagSafe charging accessories to keep the gadgets at a "safe distance" from medical devices.

    According to a support page on Apple's website updated Saturday, the tech giant advises owners keep medical devices at least 6 inches away from medical devices, or 12 inches if they are wirelessly charging.

    The iPhone 12 as well as MagSafe, a line of accessories including cases built to make wirelessly charging the smartphones easier, contain magnets to help connect better. The smartphones also have "components and radios that emit electromagnetic fields."

    The support page says devices like implanted pacemakers "might contain sensors that respond to magnets and radios when in close contact."

    Apple suggests users get in touch with their doctor or the maker of their medical device to find out what type of impact the new iPhone or accessories might have.

    A recent study in the Heart Rhythm journal tested the compatibility of the iPhone 12 with a patient who had a Medtronic Implantable Cardioverter Defibrillator (ICD), which is used to manage cardiac rhythms. The study claimed when the iPhone was brought close to the ICD, "immediate suspension of ICD therapies was noted which persisted for the duration of the test."

    https://support.apple.com/en-in/HT211900

    https://techxplore.com/news/2021-01-apple-iphone-magsafe-accessorie...

  • Dr. Krishna Kumari Challa

    Apple Watch Helps Rescue Kidnapped Woman in US: Report

    The police used the emergency ping feature to locate a kidnapped woman and rescue her.

    An Apple Watch helped the police track down a kidnapped woman in the US. Police in Selma, Texas were able to reportedly use the emergency SOS feature on Apple Watch to locate a kidnapped woman and rescue her. The Apple Watch offered accurate location data of the victim, thanks to which the police were able to rush to her. This isn't the first time the Apple Watch has been reported to have saved a life. A few months ago, the Apple Watch's heart monitoring feature helped a 25-year-old in detecting irregularity in his heartbeat and potentially saving his life.

    https://gadgets.ndtv.com/wearables/news/apple-watch-helped-rescue-k...

  • Dr. Krishna Kumari Challa

    Time-restricted eating 

    When—not what—obese mice ate reduced breast cancer risk

    Restricting eating to an eight-hour window, when activity is highest, decreased the risk of development, growth and metastasis of breast cancer in mouse models, report researchers.

    The findings, published in the January 25, 2021 edition of Nature Communications, show that time-restricted feeding—a form of intermittent fasting aligned with circadian rhythms—improved metabolic health and tumor circadian rhythms in mice with obesity-driven postmenopausal breast cancer.

    Previous research has shown that obesity increases the risk of a variety of cancers by negatively affecting how the body reacts to insulin levels and changing circadian rhythms. Now researchers were able to increase insulin sensivity, reduce hyperinsulinemia, restore circadian rhythms and reduce tumour growth by simply modifying when and for how long mice had access to food.

    Both obesity and menopause can disrupt circadian rhythms, which in turn can lead to the development of insulin resistance, predisposing individuals to chronic diseases like cancer.

    Data indicates that elevated insulin levels in obese mice are driving the accelerated tumor growth. Artificially elevating insulin levels accelerated tumor growth, whereas reducing insulin levels could mimic the effect of the time-restricted feeding. The results suggest that the antitumor effect of time-restricted feeding is due to improving metabolic health and lowering the levels of insulin.

    Time-restricted eating has a positive effect on metabolic health and does not trigger the hunger and irritability that is associated with long-term fasting or calorie restriction," said Das. "Through its beneficial metabolic effects, time-restricted eating may also provide an inexpensive, easy to adopt, but effective strategy to prevent and inhibit breast cancer without requiring a change in diet or physical activity.

    Manasi Das et al. Time-restricted feeding normalizes hyperinsulinemia to inhibit breast cancer in obese postmenopausal mouse models, Nature Communications (2021). DOI: 10.1038/s41467-020-20743-7

    https://medicalxpress.com/news/2021-01-whennot-whatobese-mice-ate-b...

  • Dr. Krishna Kumari Challa

    Microwaves used to deactivate coronavirus, flu, other aerosolized viruses

    Studies indicate the COVID-19 virus may be contained in aerosols that can be generated and spread through breathing, coughing, sneezing, or talking by infected individuals. Researchers are increasingly focused on developing tools and methods to assist in decontaminating surfaces and spaces.

    While scientists have previously explored the use of electromagnetic energy to deactivate flu virus in bulk fluids, less work has been done to understand the role of nonionizing radiation, such as microwaves, in reducing the infectivity of viral pathogens in aerosols. The tools required to both safely contain contaminated aerosol streams and expose these aerosols to controlled, well-characterized microwave doses have not been readily available.

    In Review of Scientific Instruments, researchers from the Air Force Research Laboratory report development of a set of experimental tools capable of presenting electromagnetic waves to an aerosol mixture of biological media and virus with the capability to vary power, energy, and frequency of the electromagnetic exposure. The researchers seek to better characterize the threshold levels of microwave energy needed to inactivate aerosolized viral particles and, thus, reduce their ability to spread infection.

    In teh initial expts., 

    researchers are exposing a human-safe coronavirus surrogate, bovine coronavirus, to a range of microwave waveforms at frequencies ranging from 2.8 GHz to 7.5 GHz.

    "The bovine coronavirus is similar in size and configuration to human coronavirus but is safe to human.

    "Apparatus for controlled microwave exposure of aerosolized pathogens" Review of Scientific Instrumentsaip.scitation.org/doi/10.1063/5.0032823

    https://medicalxpress.com/news/2021-01-microwaves-deactivate-corona...

  • Dr. Krishna Kumari Challa

    Discovery makes the invisible visible

    Australian scientists have discovered a new way to analyze microscopic cells, tissues and other transparent specimens, through the improvement of an almost 100-year-old imaging technique.

    --

    Supercomputers aid scientists studying the smallest particles in th...

    Since the 1930s, scientists have been using particle accelerators to gain insights into the structure of matter and the laws of physics that govern our world. These accelerators are some of the most powerful experimental tools available, propelling particles to nearly the speed of light and then colliding them to allow physicists to study the resulting interactions and particles that form.

    --

    Dogs synchronize their behavior with children, but not as much as w...

    Dogs synchronize their behavior with the children in their family, but not as much as they do with adults, a new study from Oregon State University researchers found.

  • Dr. Krishna Kumari Challa

    Physicists discover new physical effect

    Scientists have found that a perpendicular magnetic field makes electrically neutral quasiparticles (excitons) in semiconductors behave like electrons in the Hall effect. This discovery will help researchers to study the physics of excitons and Bose-Einstein condensates.

    The Hall effect can be achieved by applying a magnetic field in a direction perpendicular to the current flow of a semiconductor or a metal plate. In this case, all the electrons will deflect to one side, which will accumulate a negative charge, while the other side has a positive charge. This results in voltage between the right and left end faces of the plate.

    physicists have recently discovered a similar effect but for excitons, composite neutral quasiparticles. It occurs when a laser affects a semiconductor plate of gallium arsenide, for example, in the presence of a magnetic field. The new phenomenon was called the anomalous exciton Hall effect.

    "If you take a thin stripe of a semiconductor material and put it under a laser beam at the right angle, you'll create a directed flow of exciton gas. By applying a perpendicular magnetic field to this film, you will make the exciton cloud deflect to one side. And this is a complete analog of the Hall effect—but for neutrally charged composite quasiparticles.

    This effect will help researchers separate bright and dark excitons. When exciton gas is formed, some excitons are able to emit light once the electron returns to its place. Such quasiparticles are called bright excitons. Other excitons disappear without light emission—these are dark excitons. Although it is especially difficult to study and obtain them because both types of quasiparticles are created simultaneously, the proposed method for separating bright excitons from dark ones will successfully resolve this issue.the discovered effect is unlikely to be as widely applied Hall effect technologies used in smartphones, but it may be highly valuable for scientists who study excitons. In particular, it will greatly simplify the study of such mind-blowing and complex states of matter as Bose-Einstein condensates.

     V. K. Kozin et al. Anomalous Exciton Hall Effect, Physical Review Letters (2021). DOI: 10.1103/PhysRevLett.126.036801

    https://phys.org/news/2021-01-physicists-physical-effect.html?utm_s...

  • Dr. Krishna Kumari Challa

    Exercising muscle combats chronic inflammation on its own

    Biomedical engineers at Duke University have demonstrated that human muscle has an innate ability to ward off the damaging effects of chronic inflammation when exercised. The discovery was made possible through the use of lab-grown, engineered human muscle, demonstrating the potential power of the first-of-its-kind platform in such research endeavors. The results appear online on January 22 in the journal Science Advances. 

    --

    Exercising muscle combats chronic inflammation on its own

    Exercising lab-grown human muscle autonomously blocks the damaging effects of interferon gamma

    Biomedical engineers have demonstrated that human muscle has an innate ability to ward off damaging effects of chronic inflammation when exercised. The discovery was made possible through the use of lab-grown, engineered human muscle, demonstrating the potential power of the first-of-its-kind platform in such research endeavors.

    Zhaowei Chen, Binjie Li, Ren-Zhi Zhan, Lingjun Rao, Nenad Bursac. Exercise Mimetics and JAK Inhibition Attenuate IFN-γ-induced Wasting in Engineered Human Skeletal MuscleScience Advances, 2021 DOI: 10.1126/sciadv.eabd9502

    https://www.sciencedaily.com/releases/2021/01/210122140624.htm

    https://researchnews.cc/news/4805/Exercising-muscle-combats-chronic...

    --

    Technology could upend DNA sequencing for diagnosing certain DNA mu...

    Doctors are increasingly using genetic signatures to diagnose diseases and determine the best course of care, but using DNA sequencing and other techniques to detect genomic rearrangements remains costly or limited in capabilities. However, an innovative breakthrough developed by researchers at Virginia Commonwealth University Massey Cancer Center and the VCU Department of Physics promises to diagnose DNA rearrangement mutations at a fraction of the cost with improved accuracy.

  • Dr. Krishna Kumari Challa

    Strange colon discovery explains racial disparities in colorectal cancer

    The colons of African Americans and people of European descent age differently, new research reveals, helping explain racial disparities in colorectal cancer.

    Scientists found that one side of the colon ages biologically faster than the other in both African Americans and people of European descent. In African Americans, however, the right side ages significantly faster, explaining why African Americans are more likely to develop cancerous lesions on the right side and why they are more likely to suffer colorectal cancer at a younger age, the researchers say.

    The researchers made this determination by looking at the DNA in colon tissue, and the “epigenetic” changes that come with age. These epigenetic changes are not alterations to the genes, but changes that affect how the genes work and how well they can do their jobs.

    The scientists found that the right side of the colon in most African Americans had suffered a unique pattern of “hypermethylation,” affecting gene expression. It was, in essence, like the right side was old beyond its years. This, the researchers believe, could contribute to African Americans’ increased cancer risk and could explain why they are more likely to develop cancerous lesions on the right side.

    The research could also explain why younger people of European descent are more likely to develop lesions on the left side – the side that tends to age faster in that group.

    These findings highlight the importance of colon sidedness to biology of colorectal cancer.

    https://academic.oup.com/jnci/advance-article-abstract/doi/10.1093/...

    https://news.virginia.edu/content/strange-colon-discovery-explains-...

  • Dr. Krishna Kumari Challa

    Wearing 2 Masks Is 'Common Sense'. Here's How to Do It Properly

    US health officials have long been advising people to wear a cloth mask with three layers of protection, or a surgical or N95 mask, to protect against the novel coronavirus.

    But some people, including many at the inauguration, have been doubling up on masks - layering them to create an extra barrier of protection.

    It's a good idea, according to experts.

     

    "If you have a physical covering with one layer, you put another layer on, it just makes common sense that it likely would be more effective.

    How to double-mask

    The type of mask you double up on will affect the level of protection it provides.

    As Business Insider's Anna Medaris Miller previously reported, it's a good idea to use a surgical mask or an N95 in your layering.

    For example, it's better to use a double-layered cloth mask for the outside layer and a disposable surgical mask for the inside, rather than using two single-layered masks together.

    The three layers each serve an individual purpose: the outside layer protects against splashes and droplets, the middle layer filters, and the bottom layer absorbs things like saliva and sweat.

    Another way to double layer could be using a two-layered cloth mask with a face shield on top, though there is some evidence that masks may be more protective than shields.

    Double layering doesn't mean you should let your guard down. Public health officials say the general public should still use social distancing practices, wash their hands regularly, and avoid gathering indoors.

    https://www.sciencealert.com/fauci-says-wearing-2-masks-is-common-s...

    https://www.businessinsider.in/science/news/fauci-said-it-is-common...

  • Dr. Krishna Kumari Challa

    Cell death shines a light on the origins of complex life

    Organelles continue to thrive after the cells within which they exist die, a team of scientists have found, overturning previous assumptions that organelles decay too quickly to be fossilized.

    Researchers from  were able to document the decay process of eukaryotic algal cells, showing that nuclei, chloroplasts and pyrenoids (organelles found within chloroplasts) can persist for weeks and months after cell death in eukaryote cells, long enough to be preserved as fossils.

    The research found that organelles don't decay immediately after cell death, but actually take many weeks to dissolve. The results of these experiments shed light on the controversial fossils of early complex life that include structures within the cells.

    The structures in Shuiyousphaeridium, a fossil from 1,700 million years ago, closely resemble nuclei. This interpretation has previously been dismissed because of the assumed rapid decay of nuclei. the new decay experiments have shown that nuclei can persist for several weeks, meaning the structures in Shuiyousphaeridium are likely to be nuclei.

    By revealing the decay patterns of organelles, the study's authors say they can demonstrate the presence of complex life to 1,700 million years ago, helping to elucidate their evolutionary history with greater precision and clarity.

    "Experimental taphonomy of organelles and the fossil record of early eukaryote evolution" Sciences Advancesadvances.sciencemag.org/lookup … .1126/sciadv.abe9487

    https://phys.org/news/2021-01-cell-death-complex-life.html?utm_sour...

  • Dr. Krishna Kumari Challa

    On nights before a full moon, people go to bed later and sleep less, study shows

    New research indicates that our planet's celestial companion impacts something else entirely—our sleep.

    Scientists report that sleep cycles in people oscillate during the 29.5-day lunar cycle: In the days leading up to a full moon, people go to sleep later in the evening and sleep for shorter periods of time. The research team, led by UW professor of biology Horacio de la Iglesia, observed these variations in both the time of sleep onset and the duration of sleep in urban and rural settings—from Indigenous communities in northern Argentina to college students in Seattle, a city of more than 750,000. They saw the oscillations regardless of an individual's access to electricity, though the variations are less pronounced in individuals living in urban environments.

    The pattern's ubiquity may indicate that our natural circadian rhythms are somehow synchronized with—or entrained to—the phases of the lunar cycle. And although the effect is more robust in communities without access to electricity, the effect is present in communities with electricity.

    How phases of the moon can affect your sleep

    L. Casiraghi el al., "Moonstruck sleep: Synchronization of human sleep with the moon cycle under field conditions," Science Advances (2021). advances.sciencemag.org/lookup … .1126/sciadv.abe0465

    https://phys.org/news/2021-01-nights-full-moon-people-bed.html?utm_...

  • Dr. Krishna Kumari Challa

    Electronic Tattoo - Science of Innovation

    Electronic transfer tattoo with a crease amplification effect

    https://techxplore.com/news/2021-01-electronic-tattoo-crease-amplif...

  • Dr. Krishna Kumari Challa

    How heavy is dark matter? Scientists radically narrow the potential mass range for the first time

    Scientists have calculated the mass range for Dark Matter—and it's tighter than the science world thought.

    The findings—due to be published in Physics Letters B in March—radically narrow the range of potential masses for Dark Matter particles, and help to focus the search for future Dark Matter-hunters. The  researchers used the established fact that gravity acts on Dark Matter just as it acts on the visible universe to work out the lower and upper limits of Dark Matter's mass.

    The results show that Dark Matter cannot be either 'ultra-light' or 'super-heavy', as some have theorized, unless an as-yet undiscovered force also acts upon it.

    The team used the assumption that the only force acting on Dark Matter is gravity, and calculated that Dark Matter particles must have a mass between 10-3 eV and 107 eV. That's a much tighter range than the 10-24 eV—1019 GeV spectrum which is generally theorized.

    What makes the discovery even more significant is that if it turns out that the mass of Dark Matter is outside of the range predicted by the Sussex team, then it will also prove that an additional force—as well as gravity—acts on Dark Matter.

    This is the first time that anyone has thought to use what we know about quantum gravity as a way to calculate the mass range for Dark Matter.

     Xavier Calmet et al, Theoretical bounds on dark matter masses, Physics Letters B (2021). DOI: 10.1016/j.physletb.2021.136068

    https://phys.org/news/2021-01-heavy-dark-scientists-radically-narro...

  • Dr. Krishna Kumari Challa

    World's largest opinion survey on climate change: Majority call for wide-ranging action

    The results of the Peoples' Climate Vote, the world's biggest ever survey of public opinion on climate change are published yesterday (27/1/2021). Covering 50 countries with over half of the world's population, the survey includes over half a million people under the age of 18, a key constituency on climate change that is typically unable to vote yet in regular elections. 

    Results show that people often want broad climate policies beyond the current state of play. For example, in eight of the ten survey countries with the highest emissions from the power sector, majorities backed more renewable energy. In four out of the five countries with the highest emissions from land-use change and enough data on policy preferences, there was majority support for conserving forests and land. Nine out of ten of the countries with the most urbanized populations backed more use of clean electric cars and buses, or bicycles.

    https://www.undp.org/content/undp/en/home/news-centre/news/2021/Wor...

    https://phys.org/news/2021-01-world-largest-opinion-survey-climate....

  • Dr. Krishna Kumari Challa

    Purported phosphine on Venus more likely to be ordinary sulfur diox...

    In September, a team led by astronomers in the United Kingdom announced that they had detected the chemical phosphine in the thick clouds of Venus. The team's reported detection, based on observations by two Earth-based radio telescopes, surprised many Venus experts. Earth's atmosphere contains small amounts of phosphine, which may be produced by life. Phosphine on Venus generated buzz that the planet, often succinctly touted as a "hellscape," could somehow harbor life within its acidic clouds.

    --

    Researchers realizing the limitless possibilities of wearable elect...

    Benoît Lessard and his team are developing carbon-based technologies which could lead to improved flexible phone displays, make robotic skin more sensitive and allow for wearable electronics that could monitor the physical health of athletes in real-time.

  • Dr. Krishna Kumari Challa

    First evidence that water can be created on the lunar surface by Earth's magnetosphere

    Before the Apollo era, the moon was thought to be dry as a desert due to the extreme temperatures and harshness of the space environment. Many studies have since discovered lunar water: ice in shadowed polar craters, water bound in volcanic rocks, and unexpected rusty iron deposits in the lunar soil. Despite these findings, there is still no true confirmation of the extent or origin of lunar surface water.

    The prevailing theory is that positively charged hydrogen ions propelled by the solar wind bombard the lunar surface and spontaneously react to make water (as hydroxyl (OH-) and molecular (H2O)). However, a new multinational study published in Astrophysical Journal Letters proposes that solar wind may not be the only source of water-forming ions. The researchers show that particles from Earth can seed the moon with water, as well, implying that other planets could also contribute water to their satellites.

    Earth wind as a possible source of lunar surface hydration. arxiv.org/abs/1903.04095

    https://phys.org/news/2021-01-evidence-lunar-surface-earth-magnetos...

    --

    Though the solar wind is a likely source for lunar surface water, computer models predict that up to half of it should evaporate and disappear at high-latitude regions during the approximately three days of the full moon when it passes within Earth's magnetosphere.

  • Dr. Krishna Kumari Challa


  • Dr. Krishna Kumari Challa

    Drugs used to treat HIV and flu can have detrimental impact on crops

    The increased global use of antiviral and antiretroviral medication could have a detrimental impact on crops and potentially heighten resistance to their effects, new research has suggested.

  • Dr. Krishna Kumari Challa

    Researchers develop smartphone-based COVID-19 test that delivers results in about 10 minutes

    Researchers at the University of Arizona are developing a COVID-19 testing method that uses a smartphone microscope to analyze saliva samples and deliver results in about 10 minutes.

    The research team aims to combine the speed of existing nasal swab antigen tests with the high accuracy of nasal swab PCR, or polymerase chain reaction, tests. The researchers are adapting an inexpensive method that they originally created to detect norovirus—the microbe famous for spreading on cruise ships—using a smartphone microscope.

    Nature Protocols (2021). DOI: 10.1038/s41596-020-00460-7

    https://medicalxpress.com/news/2021-01-smartphone-based-covid-resul...

  • Dr. Krishna Kumari Challa

    Specific bacteria in the gut prompt mother mice to neglect their pups

    As scientists learn more about the microorganisms that colonize the body—collectively called the microbiota—one area of intense interest is the effect that these microbes can have on the brain. A new study led by Salk Institute scientists has identified a strain of E. coli bacteria that, when living in the guts of female mice, causes them to neglect their offspring.

    The findings show  a direct link between a particular microbe and maternal behavior. Although the research was done in mice, it adds to the growing body of science demonstrating that microbes in the gut are important for brain health and can affect development and behaviour.

     this is the first demonstration that the intestinal microbiota is important for promoting healthy maternal behavior and bonding between mom and offspring in an animal model.

     It is  difficult to study how individual strains of bacteria exert their influence on human behaviour, a connection often called the microbiota-gut-brain axis.

    This study study provides an unprecedented understanding of how the intestinal microbiota can disrupt maternal behavior and how this can negatively impact development of an offspring.

    Microbiota control of maternal behavior regulates early postnatal growth of offspring, Science Advances (2021). DOI: 10.1126/sciadv.abe6563 , advances.sciencemag.org/content/7/5/eabe6563

    https://phys.org/news/2021-01-specific-bacteria-gut-prompt-mother.h...

  • Dr. Krishna Kumari Challa

    'Weak' and 'strong' cells bonding boosts body's diabetes fight

    Scientists have broadened our understanding of how 'weak' cells bond with their more mature cellular counterparts to boost the body's production of insulin, improving our knowledge of the processes leading to type 2 diabetes—a significant global health problem.

    Type 2 diabetes mellitus occurs when β-cells cannot release enough insulin—a tightly controlled process requiring hundreds of such cells clustered together to co-ordinate their response to signals from food, such as sugar, fat and gut hormones.

    Now an international research team have discovered that immature β-cells (PDX1LOW/MAFALOW) are able to overcome their relative deficiencies by partnering with 'stronger' counterparts to drive insulin release.  The researchers reveal that subtle differences in the levels of PDX1 and MAFA proteins (found only in β-cells) , and more broadly, differences in β-cell maturity, contribute to how clusters of insulin-producing cells, known as islets, function. 

    The study shows that differences in β-cell maturity, defined using PDX1 and MAFA levels, are needed across the islet for proper insulin release. Unexpectedly, increases in the proportion of mature β-cells, is associated with islet failure. It seems that, rather like society, the islet needs cells with all ages to be properly functional.

    Redressing the balance between immature and mature β-cells restores islet function under conditions of metabolic stress—an excess of sugar and fat in the diet—providing evidence that both 'weak' and 'strong' β-cells could contribute to proper islet function and insulin release.

    "This is the first glimpse that immature cells might contribute to the regulation of insulin release across the islet. The study indicates a promising line of investigation that could be leveraged to make islets more resilient during type 2 diabetes or when generating new islets in a 'dish' for the purpose of transplantation."

    'PDX1LOW MAFALOW β-cells contribute to islet function and insulin release' Daniela Nasteska, Nicholas H. F. Fine, Fiona B. Ashford, Federica Cuozzo, Katrina Viloria, Gabrielle Smith, Aisha Dahir, Peter W. J. Dawson, Yu-Chiang Lai, Aimée Bastidas-Ponce, Mostafa Bakhti, Guy A. Rutter, Remi Fiancette, Rita Nano, Lorenzo Piemonti, Heiko Lickert, Qiao Zhou, Ildem Akerman and David J. Hodson is published in Nature CommunicationsDOI: 10.1038/s41467-020-20632-z

    https://medicalxpress.com/news/2021-01-weak-strong-cells-bonding-bo...

  • Dr. Krishna Kumari Challa

    Threads that sense how and when you move? New technology makes it possible

    Engineers at Tufts University have created and demonstrated flexible thread-based sensors that can measure movement of the neck, providing data on the direction, angle of rotation and degree of displacement of the head. The discovery raises the potential for thin, inconspicuous tatoo-like patches that could, according to the Tufts team, measure athletic performance, monitor worker or driver fatigue, assist with physical therapy, enhance virtual reality games and systems, and improve computer generated imagery in cinematography. The technology, described today in Scientific Reports, adds to a growing number of thread-based sensors developed by Tufts engineers that can be woven into textiles, measuring gases and chemicals in the environment or metabolites in sweat.

    Scientific Reports (2021). DOI: 10.1038/s41598-021-81284-7

    https://techxplore.com/news/2021-01-threads-technology.html?utm_sou...