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  • Dr. Krishna Kumari Challa

    A revolutionary gene therapy is bringing hope to UK parents - but it comes with a steep price tag

    A baby in England has been the first patient on the country’s NHS to receive a potentially life-saving new gene therapy to treat spinal muscular atrophy (SMA).

    Five-month-old Arthur Morgan was given a dose of the treatment known as Zolgensma at Evelina London Children's Hospital on May 25.

    Arthur was born in December last year and diagnosed with SMA, a rare and debilitating neuromuscular disease that prevents muscle development, just a few weeks ago.

    Babies born with SMA experience problems with movement, breathing, and swallowing.

    The novel gene therapy treatment, produced by US pharma giant Novartis Gene Therapies, repairs affected genes inside the cells, making it easier to manage and potentially cure the disease.

    But the wonder drug comes at a price. Zolgensma is one of the world's most expensive drugs with a price tag per dose of €2.08 million. Fortunately for Arthur and his family, the NHS negotiated a non-disclosed discounted price for the drug, making it more accessible for patients suffering from SMA to receive the treatment.

     the importance of using innovative therapies to treat diseases and disorders, such as in this case.

    "It is fantastic news that this revolutionary treatment is now available for babies and children like Arthur on the NHS.

    These are hugely transformative therapies. To bring something in that only requires treatment once, that actually requires a lot of systems and processes to change

    The agreement between Novartis and the NHS is part of a "series of smart deals" aimed to secure more cutting-edge treatments for the British people, according to the NHS website.

    Novartis says that while the cost of the single-dose treatment sounds expensive, it isn’t when you compare the alternative treatment for SMA which can include ongoing hospital admissions, ventilators and round-the-clock care. When you consider lifetime costs - actually gene therapies aren’t expensive.

    Is Zolgensma 's a complete cure given the many variables, including when the infant is diagnosed and when the drug is administered, he does believe there is a curative future for gene therapy drugs "if the entire system is in sync".

    It is moving into a genomic era which is an era of medicine where we can harness our understanding of genetics and the impact on health in a much great way.

    https://www.euronews.com/2021/06/01/gene-therapy-life-saving-drug-b...

    **

  • Dr. Krishna Kumari Challa

    Tweaking gene therapy: Scientists experimentally boost red blood cells to aid sickle cell and other hemoglobin diseases

    A series of laboratory studies is underway to improve gene therapy worldwide for sickle cell disease, a complex and sometimes deadly heritable blood disorder that dramatically affects the structure and function of oxygen-ferrying red blood cells.

    Sickle cell disease is a devastating disorder that largely affects people of African descent. The genetic condition derives its name from the shape of patients' red blood cells, which have the configuration of a crescent moon or sickle. As one of the heritable hemoglobin diseases, doctors say the condition is related to beta thalassemia, which is largely seen in populations throughout the Mediterranean, parts of the Mideast and Asia. In that disease, red blood cells do not sickle but are substantially smaller than normal, and likewise are impaired as transporters of oxygen.

    About a dozen gene therapy clinical trials are being conducted in the U.S., but laboratory research designed to improve the technology remains exceptionally active and robust. The aim of all gene therapy technologies for hemoglobin diseases is to produce healthy disc-shaped red blood cells that efficiently transport oxygen throughout the body. In the case of sickle cell disease, the treatment corrects a constellation of medical problems—hemolytic anemia, pain, and organ damage.

    have designed a new gene therapy strategy for sickle cell disease—and other hemoglobin diseases—that boosts levels of fetal hemoglobin by increasing gamma-globin concentrations. Fetal hemoglobin is produced during fetal development and is more efficient at transporting oxygen than its adult counterpart. Producing fetal hemoglobin is a capability that can be revived through gene therapy. Boosting levels of fetal hemoglobin not only increases oxygen transport but dramatically lowers the frequency of disease complications.

    Just as levels of fetal hemoglobin are boosted in a reimagined and improved form of gene therapy, Uchida and a team of scientists at the Heart, Lung, and Blood Institute have devised a method to also boost gamma-globin in a single gene therapy treatment. Gamma-globin is a component of the hemoglobin molecule, the iron-containing oxygen-transport metalloprotein in red blood cells. Gamma-globin is a member of the globin superfamily of proteins involved in binding and transporting oxygen.

    Naoya Uchida et al. Sustained fetal hemoglobin induction in vivo is achieved by BCL11A interference and coexpressed truncated erythropoietin receptor, Science Translational Medicine (2021) DOI: 10.1126/scitranslmed.abb0411

    https://medicalxpress.com/news/2021-05-tweaking-gene-therapy-scient...

  • Dr. Krishna Kumari Challa

    Light-shrinking material lets ordinary microscope see in super resolution

    Electrical engineers developed a technology that improves the resolution of an ordinary light microscope so that it can be used to directly observe finer structures and details in living cells.

    The technology turns a conventional light microscope into what's called a super-resolution microscope. It involves a specially engineered material that shortens the wavelength of light as it illuminates the sample—this shrunken light is what essentially enables the microscope to image in higher resolution.

    This material converts low resolution light to high resolution light. It's very simple and easy to use. Just place a sample on the material, then put the whole thing under a normal microscope—no fancy modification needed.

    Yeon Ui Lee et al, Metamaterial assisted illumination nanoscopy via random super-resolution speckles, Nature Communications (2021). DOI: 10.1038/s41467-021-21835-8

    https://phys.org/news/2021-06-light-shrinking-material-ordinary-mic...

  • Dr. Krishna Kumari Challa

    Falcons have natural 'eye makeup' to improve hunting ability

    Dark 'eyeliner' feathers of peregrine falcons act as sun shields to improve the birds' hunting ability, a new scientific study suggests. Scientists have long speculated that falcons' eye markings improve their ability to target fast-moving prey, like pigeons and doves, in bright sunlight. Now research suggests these markings have evolved according to the climate; the sunnier the bird's habitat, the larger and darker are the tell-tale dark 'sun-shade' feathers.

    Michelle Vrettos, Chevonne Reynolds, Arjun Amar. Malar stripe size and prominence in peregrine falcons vary positively with solar radiation: support for the solar glare hypothesisBiology Letters, 2021; 17 (6): 20210116 DOI: 10.1098/rsbl.2021.0116

    https://www.sciencedaily.com/releases/2021/06/210601194155.htm

  • Dr. Krishna Kumari Challa

    World's lakes losing oxygen rapidly as planet warms

    Oxygen levels in the world's temperate freshwater lakes are declining rapidly—faster than in the oceans—a trend driven largely by climate change that threatens freshwater biodiversity and drinking water quality.

    Research published recently in Nature found that oxygen levels in surveyed lakes across the temperate zone have declined 5.5% at the surface and 18.6% in deep waters since 1980. Meanwhile, in a large subset of mostly nutrient-polluted lakes, surface oxygen levels increased as water temperatures crossed a threshold favoring cyanobacteria, which can create toxins when they flourish in the form of harmful algal blooms.

    All complex life depends on oxygen. It's the support system for aquatic food webs. And when you start losing oxygen, you have the potential to lose species. Lakes are losing oxygen 2.75-9.3 times faster than the oceans, a decline that will have impacts throughout the ecosystem.  

    Widespread deoxygenation of temperate lakes, Nature (2021). DOI: 10.1038/s41586-021-03550-y , www.nature.com/articles/s41586-021-03550-y

    https://phys.org/news/2021-06-world-lakes-oxygen-rapidly-planet.htm...

  • Dr. Krishna Kumari Challa

    Blood clot-busting nanocapsules could reduce existing treatment's side effects

    "Fibrinogen-mimicking, multiarm nanovesicles for human thrombus-specific delivery of tissue plasminogen activator and targeted thrombolytic therapy" Science Advances (2021). advances.sciencemag.org/lookup … 1126/sciadv.eabf9033

    https://phys.org/news/2021-06-blood-clot-busting-nanocapsules-treat...

  • Dr. Krishna Kumari Challa

    Human brain and testis found to have the highest number of common proteins

    A team of researchers  has found that for humans, the brain and testis have the highest number of common proteins. In their paper published in the journal Royal Society Open Biology, the group describes their study of protein similarities between tissues.

    In this new effort, the researchers noted that evidence from other studies has found some signs of similarities between testis and the human brain. Intrigued, they initiated a study that involved analyzing the proteins produced by different parts of the body and then comparing them to see similarities. The researchers found the greatest similarities between the brain and testicles—13,442 of them. This finding suggests that the brain and the testicles share the highest number of genes of any organs in the body.

    The team next focused on the shared proteins and found that most of them were involved in the development of tissue and communications. They suggest this finding was not surprising, considering that proteins from both organs consume high amounts of fuel—one to process thinking, the other to produce millions of sperm every day. They also note that testis and nerve cells are both involved in moving material created inside of them to an outside environment—sperm cells move fertilization factors and neurons move neurotransmitters. Both are part of processes known as exocytosis. Additionally, as part of exocytosis, sperm allow parts of themselves to fuse with an egg. With neurons, exocytosis involves creating neurites that allow for communication between cells.

    Bárbara Matos et al, Brain and testis: more alike than previously thought?, Open Biology (2021). DOI: 10.1098/rsob.200322

    https://phys.org/news/2021-06-human-brain-testis-highest-common.htm...

  • Dr. Krishna Kumari Challa

    Atmospheric metal layers appear with surprising regularity

    Twice a day, at dusk and just before dawn, a faint layer of sodium and other metals begins sinking down through the atmosphere, about 90 miles high above the city of Boulder, Colorado. The movement was captured by one of the world's most sensitive "lidar" instruments and reported recently in the AGU journal Geophysical Research Letters.

    The metals in those layers come originally from rocky material blasting into Earth's atmosphere from space, and the regularly appearing layers promise to help researchers understand better how earth's atmosphere interacts with space, even potentially how those interactions help support life.

    This is an important discovery because we have never seen these dusk/dawn features before, and because these metal layers affect many things. The metals can fall into the ocean and act as fertilizer for ecosystems, the ionized metals can affect GPS radio signals.

    It is the first time that the metal layers—which are not harmful to people—have been seen so regularly at these extreme heights in the atmosphere. Such high-altitude metal layers were discovered by Chu's group just 10 years ago above McMurdo, Antarctica, but there they occur more sporadically. Above Boulder, they're consistent, daily, and synched with winds that occur high in the atmosphere.

    Xinzhao Chu et al, Mid‐Latitude Thermosphere‐Ionosphere Na (TINa) Layers Observed With High‐Sensitivity Na Doppler Lidar Over Boulder (40.13°N, 105.24°W), Geophysical Research Letters (2021). DOI: 10.1029/2021GL093729

    https://phys.org/news/2021-06-atmospheric-metal-layers-regularity.h...

  • Dr. Krishna Kumari Challa

    What if the black hole at the center of the Milky Way is actually a...

    A team of researchers at the International Center for Relativistic Astrophysics has found evidence that suggests Sagittarius A* is not a massive black hole but is instead a mass of dark matter. In their paper published in the journal Monthly Notices of the Royal Astronomical Society: Letters, the group describes the evidence they found and how it has stood up to testing.

  • Dr. Krishna Kumari Challa

    Deadly river ‘earthquakes’ could be manageable

  • Dr. Krishna Kumari Challa

    Scientists make powerful underwater glue inspired by barnacles and mussels

    A new type of glue inspired by the stubbornly adherent crustaceans has been developed by researchers.

    Starting with the fibrous silk protein harvested from silkworms, they were able to replicate key features of barnacle and mussel glue, including protein filaments, chemical crosslinking and iron bonding. The result is a powerful non-toxic glue that sets and works as well underwater as it does in dry conditions and is stronger than most synthetic glue products now on the market.

    The Silklab "glue crew" focused on several key elements to replicate in aquatic adhesives. Mussels secrete long sticky filaments called byssus. These secretions form polymers, which embed into surfaces, and chemically cross-link to strengthen the bond. The protein polymers are made up of long chains of amino acids including one, dihydroxyphenylalanine (DOPA), a catechol-bearing amino acid that can cross-link with the other chains. The mussels add another special ingredient—iron complexes—that reinforce the cohesive strength of the byssus.

    Barnacles secrete a strong cement made of proteins that form into polymers which anchor onto surfaces. The proteins in barnacle cement polymers fold their amino acid chains into beta sheets—a zig-zag arrangement that presents flat surfaces and plenty of opportunities to form strong hydrogen bonds to the next protein in the polymer, or to the surface to which the polymer filament is attaching.

    Michael A. North et al. High Strength Underwater Bonding with Polymer Mimics of Mussel Adhesive Proteins, ACS Applied Materials & Interfaces (2017). DOI: 10.1021/acsami.7b00270

    https://phys.org/news/2021-06-scientists-powerful-underwater-barnac...

    https://phys.org/news/2017-03-biomimetic-high-strength-bonding.html

    Biomimetic Underwater Glue

  • Dr. Krishna Kumari Challa

    Luring bacteria into a trap

    Developing vaccines against bacteria is in many cases much more difficult than vaccines against viruses. Like virtually all pathogens, bacteria are able to sidestep a vaccine's effectiveness by modifying their genes. For many pathogens, such genetic adaptations under selective pressure from vaccination will cause their virulence or fitness to decrease. This lets the pathogens escape the effects of vaccination, but at the price of becoming less transmissible or causing less damage. Some pathogens, however, including many bacteria, are extremely good at changing in ways that allow them to escape the effects of vaccination while remaining highly infectious. For scientists looking to develop vaccines, this kind of immune evasion has been a fundamental problem for decades. If they set out to develop vaccines against bacterial pathogens, often they will notice that these quickly become ineffective. Now, however, researchers have exploited precisely this mechanism to come up with an effective vaccine against bacteria. They succeeded in developing a Salmonella vaccine that, instead of trying to outright kill intestinal bacteria, rather guides their evolution in the gut to make them a weaker pathogen.

    the researchers inoculated mice with a series of slightly different vaccines against Salmonella typhimurium, and observed how the Salmonella in the animals’ guts modified their genes to escape the vaccines’ effects. This let the scientists identify the full spectrum of possible immune evasion mutations in Salmonella typhimurium. Subsequently, the researchers produced a combination vaccine from four Salmonella strains that covered the bacteria’s full spectrum of genetic evasion options.

    A surprising immune evasion was driven by this combined vaccine, causing an important Salmonella sugar coating on the surface to atrophy. While the affected bacteria were still able to multiply in the animals’ guts, they were largely unable to infect body tissues and cause disease. This is because the sugar coating is part of the bacteria’s protective coating that shields them from the host’s defences as well as from viruses that often infect and kill the bacteria. In tests on mice, the scientists were able to show that their new vaccine was more effective at preventing Salmonella infections than existing vaccines approved for use in pigs and chickens.

    The scientists now plan to use the same principle to develop vaccines against other microorganisms – for example, against antimicrobial-​resistant bacterial strains. In addition, it ought to be possible to use the approach in biotechnology and bring about specific modifications in microorganisms by exerting selective pressure through vaccines.

    https://ethz.ch/en/news-and-events/eth-news/news/2021/06/luring-bac...

  • Dr. Krishna Kumari Challa

    Diard M, Bakkeren E, Lentsch V, Rocker A, Amare Bekele N, Hoces D, Aslani S, Arnoldini M, Böhi F, Schumann-​Moor K, Adamcik J, Piccoli L, Lanzavecchia A, Stadtmueller BM, Donohue N, van der Woude MW, Hockenberry A, Viollier PH, Falquet L, Wüthrich D, Bonfiglio F, Loverdo C, Egli A, Zandomeneghi G, Mezzenga R, Holst O, Meier BH, Hardt WD, Slack E: A rationally designed oral vaccine induces immunoglobulin A in the murine gut that directs the evolution of attenuated Salmonella variants. Nature Microbiology, 27 May 2021, doi: 10.1038/s41564-​021-00911-1

    Evolutionary Trap Vaccines to combat drug resistant bacteria

    The Spark Award 2020 of ETH Zurich stands for the most promising invention, which was filed for a patent in 2019. The presented technology is among the top 5 nominees.

  • Dr. Krishna Kumari Challa

    COVID Sweat Sensor Catches Your Immune System Before It Goes Berserk 

    Early in the COVID-19 pandemic, doctors recognized that patients who developed a surge of pro-inflammatory immune proteins, also known as a “cytokine storm,” were often the sickest and at the greatest risk of dying. While blood tests can measure cytokines, they can’t continuously monitor a patient’s protein levels. Researchers at EnliSense LLC and the University of Texas have developed a wristwatch-like device that can track cytokine levels through a patient’s sweat, allowing doctors time to proactively administer medicines like steroids if they see cytokine levels rising.

    **

  • Dr. Krishna Kumari Challa

    Deep-Earth microbes feed on radioactivity

    Scientists have long puzzled over how microbes living deep underground feed themselves without sunlight or heat. Now, two studies suggest that these organisms could feed off the radioactive decay of hydrogen and other elements. The findings open up new possibilities for life on other worlds — and could shed some light on our planet’s own history.

    --

    Radioactivity May Fuel Life Deep Underground and Inside Other Worlds

    New work suggests that the radiolytic splitting of water supports giant subsurface ecosystems of life on Earth — and could do it elsewhere, too.
    https://www.quantamagazine.org/radioactivity-may-fuel-life-deep-und...
  • Dr. Krishna Kumari Challa

    New form of silicon could enable next-gen electronic and energy devices

    A research team developed a new method for synthesizing a novel crystalline form of silicon with a hexagonal structure that could potentially be used to create next-generation electronic and energy devices with enhanced properties that exceed those of the "normal" cubic form of silicon used today.

    Like all elements, silicon can take different crystalline forms, called allotropes, in the same way that soft graphite and super-hard diamond are both forms of carbon. The form of silicon most commonly used in electronic devices, including computers and solar panels, has the same structure as diamond. Despite its ubiquity, this form of silicon is not actually fully optimized for next-generation applications, including high-performance transistors and some photovoltaic devices.

    While many different silicon allotropes with enhanced physical properties are theoretically possible, only a handful exist in practice given the lack of known synthetic pathways that are currently accessible.

    Thomas B. Shiell et al, Bulk Crystalline 4H-Silicon through a Metastable Allotropic Transition, Physical Review Letters (2021). DOI: 10.1103/PhysRevLett.126.215701

    https://phys.org/news/2021-06-silicon-enable-next-gen-electronic-en...

  • Dr. Krishna Kumari Challa

    Rapid, blood test could confirm COVID-19 vaccination in minutes

    One challenge as society reopens is identifying who has been vaccinated for SARS-CoV-2, the virus that causes COVID-19. A team of  researchers has developed a rapid blood test that could confirm a person has been vaccinated while they wait to board a plane or enter a sporting event.

    Their COVID-19 antibody test is similar to one used at home to determine blood type, where the user pricks a finger and places a drop of blood on a card. A fusion protein developed by the research team is housed on the card and detects COVID-19 antibodies, tiny proteins in the blood the immune system produces to "remember" viral encounters and provide immunity to future infections. Results come back in less than five minutes, faster than current lateral flow tests to detect antibodies at point of care, while also potentially providing a clearer result.

    It could be used to confirm a person's vaccination instead of having to show a vaccine card.

    Robert L. Kruse et al, A hemagglutination-based, semi-quantitative test for point-of-care determination of SARS-CoV-2 antibody levels, medRxiv (2021). DOI: 10.1101/2021.05.01.21256452

    https://medicalxpress.com/news/2021-06-rapid-at-home-blood-covid-va...

    Rapid, Point-of-Care, SARS-CoV-2 Antibody Test based on Hemagglutination

  • Dr. Krishna Kumari Challa

    How to retard time for cells

    Scientists at Leipzig University, in collaboration with colleagues from Germany and England, have succeeded in reversibly slowing down cellular processes. A team of biophysicists led by Professor Josef Alfons Käs and Dr Jörg Schnauß were able to show in experiments that cells can be transferred into slow motion without changing the temperature.

  • Dr. Krishna Kumari Challa

    How to retard time for cells

    Scientists have succeeded in reversibly slowing down cellular processes. A team of biophysicists were able to show in experiments that cells can be transferred into slow motion without changing the temperature.

     Cells are not only our biological building blocks, but also highly dynamic, active systems. The research group  has succeeded in significantly reducing these dynamics with heavy water, without damaging the cells. For cells, time—or, more specifically, their dynamics—can be significantly slowed down in the presence of heavy water.

    The research showed on various biological levels that the movement of cells and their dynamics was only taking place in slow motion.

    The researchers confirmed this effect with a variety of complementary methods and attributed the observations to an increased interaction between the structural proteins. "Heavy water also forms hydrogen bonds, but these are stronger than in normal aqueous environments. As a result, structural proteins such as actin seem to interact more strongly with one another and briefly stick together. What is spectacular here is that the effects are reversible, with cells showing their native properties again as soon as they are transferred into a normal aqueous medium.

    These changes show the fingerprint of a passive material. However, cells are highly active and far from thermodynamic equilibrium. If they behave like a passive material, they are usually dead. However, as the researchers were able to show, this was not the case in their experiments. They now hope to be able to use the knowledge gained to keep cells or even tissue vital for longer. If this approach is confirmed, heavy water could be used for longer storage times, for example during organ transplants.

    Jörg Schnauß et al, Cells in Slow Motion: Apparent Undercooling Increases Glassy Behavior at Physiological Temperatures, Advanced Materials (2021). DOI: 10.1002/adma.202101840

    https://phys.org/news/2021-06-retard-cells.html?utm_source=nwletter...

  • Dr. Krishna Kumari Challa

    Mockingbird song decoded

    The North American mockingbird is famous for its ability to imitate the song of other birds. But it doesn't just mimic its kindred species, it actually composes its own songs based on other birds' melodies. An interdisciplinary research team has now worked out how exactly the mockingbird constructs its imitations. The scientists determined that the birds follow similar musical rules as those found in human music, from Beethoven to Kendrick Lamar.

    --

    The human genome: filling in the blanks

    Scientists are a step closer to completely sequencing the entire human genome. An international collaboration of researchers has worked out how some stretches of DNA containing many repeating letters (or base pairs) fit together, and discovered about 115 genes that code for proteins in the process. The newly sequenced genome adds nearly 200 million base pairs to the most recent human genome sequence, which researchers have used as a reference since 2013.

    A complete human genome sequence is close: how scientists filled in the gaps

  • Dr. Krishna Kumari Challa

    New study may help explain low oxygen levels in COVID-19 patients

     A new study published in the journal Stem Cell Reports by University of Alberta researchers is shedding light on why many COVID-19 patients, even those not in hospital, are suffering from hypoxia—a potentially dangerous condition in which there is decreased oxygenation in the body’s tissues. The study also shows why the anti-inflammatory drug dexamethasone has been an effective treatment for those with the virus.

    Low blood-oxygen levels have been a significant problem in COVID-19 patients.

    One potential mechanism might be that COVID-19 impacts red blood cell production.

    In the study, the research team examined the blood of 128 patients with COVID-19. The patients included those who were critically ill and admitted to the ICU, those who had moderate symptoms and were admitted to hospital, and those who had a mild version of the disease and only spent a few hours in hospital. The researchers found that, as the disease became more severe, more immature red blood cells flooded into blood circulation, sometimes making up as much as 60 per cent of the total cells in the blood. By comparison, immature red blood cells make up less than one per cent, or none at all, in a healthy individual’s blood.

    Immature red blood cells reside in the bone marrow and we do not normally see them in blood circulation. This indicates that the virus is impacting the source of these cells. As a result, and to compensate for the depletion of healthy immature red blood cells, the body is producing significantly more of them in order to provide enough oxygen for the body.

    The problem is that immature red blood cells do not transport oxygen—only mature red blood cells do. The second issue is that immature red blood cells are highly susceptible to COVID-19 infection. As immature red blood cells are attacked and destroyed by the virus, the body is unable to replace mature red blood cells—which only live for about 120 days—and the ability to transport oxygen in the bloodstream is diminished.

    The question was how the virus infects the immature red blood cells. It was found that immature red blood cells expressed the receptor ACE2 and a co-receptor, TMPRSS2, which allowed SARS-CoV-2 to infect them.

    These findings are exciting but also show two significant consequences: First, immature red blood cells are the cells being infected by the virus, and when the virus kills them, it forces the body to try to meet the oxygen supply requirements by pumping more immature red blood cells out of the bone marrow. But that just creates more targets for the virus.

    Second, immature red blood cells are actually potent immunosuppressive cells; they suppress antibody production and they suppress T-cell immunity against the virus, making the entire situation worse. So more immature red blood cells means a weaker immune response against the virus.

    When the team began exploring why dexamethasone had such an effect, they found two potential mechanisms. First, dexamethasone suppresses the response of the ACE2 and TMPRSS2 receptors to SARS-CoV-2 in immature red blood cells, reducing the opportunities for infection. Second, dexamethasone increases the rate at which the immature red blood cells mature, helping the cells shed their nuclei faster. Without the nuclei, the virus has nowhere to replicate.

    https://researchnews.cc/news/7075/New-study-may-help-explain-low-ox...

  • Dr. Krishna Kumari Challa

    Part 2:

    Shima Shahbaz, Lai Xu, Mohammed Osman, Wendy Sligl, Justin Shields, Michael Joyce, D. Lorne Tyrrell, Olaide Oyegbami, Shokrollah Elahi. Erythroid precursors and progenitors suppress adaptive immunity and get invaded by SARS-CoV-2Stem Cell Reports, 2021; 16 (5): 1165 DOI: 10.1016/j.stemcr.2021.04.001

  • Dr. Krishna Kumari Challa

    Part 1

    Doctors have been blamed for the rise in black fungus in India, but the COVID treatment guidelines could be contributing

    The emergence of black, white and yellow fungal infections are causing concern in India (1,2).

    People use use black, white and yellow fungus to refer to mucormycosis, aspergillosis, candidiasis and cryptococcosis. Together, they are referred to as invasive fungal infections, and they usually infect people with an impaired immune system, or with damaged tissue. These are said to have been caused by misuse of steroids and antibiotics (which impair our ability to fight these fungal infections) in COVID treatments, and high numbers of patients with poorly controlled diabetes where tissue is damaged (3).

    Could the situation have been averted? Perhaps, if the government had considered recent evidence and issued clear guidelines on using steroids and antiobiotics in treating COVID-19.

  • Dr. Krishna Kumari Challa

    Part 2:

    The two most recent versions of COVID treatment guidelines in India (June 27, 2020 and May 24, 2021) rightly state antibiotics should not be prescribed routinely.

    Instead, they urge doctors to consider “empiric” antibiotic therapy as per a “local antibiogram” when COVID patients have moderate secondary infections. Empiric antibiotic therapy implies making a diagnosis based on what the literature says is the most likely pathogen (or bug) causing the infection. Antibiograms are sent out to hospitals periodically and they describe the current infections circulating in the area and which antiobiotics work against them.

    For severe secondary infections, the guidelines suggest conducting blood cultures to check which antibiotic might work, ideally before the medication is started.

    An empirical approach can work effectively only if a majority of COVID facilities treating moderate cases have access to local antibiograms. If they don’t, doctors will usually end up prescribing broad-spectrum antibiotics. Broad-spectrum antiobiotics kill a range of bugs, rather than a specific one, which is risky because they can also kill the good bugs we use to fight off things like fungal infections

  • Dr. Krishna Kumari Challa

    Part 3: 

    study of ten Indian hospitals found 74% of patients with secondary infections during the first wave were given antibiotics the WHO has said should be used sparingly, and another 9% received antibiotics that were not recommended.

    The guidelines should advise the same procedure for moderate and severe cases, that is, to conduct blood cultures before starting patients on antimicrobial therapy to ensure the antibiotics will work, and that they won’t lead to a secondary fungal infection.

    One of the recommended COVID treatments of the National Institute of Health in the US is 32mg a day of the steroid methylprednisolone.

    In March 2020, Indian guidelines for treatment recommended 1-2mg methyprednisolone per kilo of body weight for patients with severe symptoms (so 70-140mg for a 70kg person).

    This was updated in June 2020 with a lower dose of methylprednisolone (35–70mg per day for a 70kg person) for three days for moderate cases and the original recommended dose (70–140mg per day for a 70kg person) for five to seven days for severe cases.

    The most recent guideline of April 2021 does not alter the dosage per day but recommended an increased duration of therapy, five to ten days, for both moderate and severe cases.

  • Dr. Krishna Kumari Challa

    Part 4:

    Despite that, the Indian recommendation still works out to a wide range across moderate and severe categories — from a low of about 35 mg to a high of 140 mg (for a 70kg person). This is in sharp contrast to the 32mg (total daily dose) recommendation in the US.

    Indian government spokespersons have attributed the rise in fungal infections to the fact doctors in the country may have irrationally used steroids.

    But given the government’s own guidelines for steroid use are so much higher than in other countries, there should be analysis into whether this may be contributing to the significant rise in fungal infections (3).

    Those findings would have profound implications on India’s pandemic management.

    Footnotes: 

    1. Now we have white and yellow fungi to deal with
    2. Potentially fatal 'black fungus' infections in COVID-19 patients
    3. Doctors have been blamed for the rise in black fungus in India, but...
  • Dr. Krishna Kumari Challa

    A framework to simulate the same physics using two different Hamiltonians

    Researchers  have recently been investigating situations in which two distinct Hamiltonians could be used to simulate the same physical phenomena. A Hamiltonian is a function or model used to describe a dynamic system, such as the motion of particles.

    In a paper published in Physical Review Letters,  researchers introduced a framework that could prove useful for simulating the same physics with two distinct Hamiltonians. In addition, they provide an example of an analog simulation and show how one could build an alternative version of a digital quantum simulator.

    Their result indicates that using the same Hamiltonian is not always a necessary condition. As an example, they showed that the physics of one-axis twisting can be simulated by a spin chain with an external field, even though the one-axis twisting model has infinite range interactions and this spin chain model has only nearest-neighboring interactions. The Hamiltonian of these two models are physically different, i.e. having different energy spectra, but still one can simulate the one with the other if the dynamics starts with special states.

     Simulating the same physics with two distinct Hamiltonians. Physical Review Letters(2021). DOI: 10.1103/PhysRevLett.126.160402.

    https://phys.org/news/2021-06-framework-simulate-physics-hamiltonia...

  • Dr. Krishna Kumari Challa

    A new material made from carbon nanotubes can generate electricity by scavenging energy from its environment

    Engineers have discovered a new way of generating electricity using tiny carbon particles that can create a current simply by interacting with liquid surrounding them.

    The liquid, an organic solvent, draws electrons out of the particles, generating a current that could be used to drive chemical reactions or to power micro- or nanoscale robots, the researchers say.

    "This mechanism is new, and this way of generating energy is completely new.

    When a carbon nanotube is coated with layer of fuel, moving pulses of heat, or thermopower waves, travel along the tube, creating an electrical current.

    This technology is intriguing because all you have to do is flow a solvent through a bed of these particles. This allows you to do electrochemistry, but with no wires.

    In a new study describing this phenomenon, the researchers showed that they could use this electric current to drive a reaction known as alcohol oxidation—an organic chemical reaction that is important in the chemical industry.

    Albert Tianxiang Liu et al, Solvent-induced electrochemistry at an electrically asymmetric carbon Janus particle, Nature Communications (2021). DOI: 10.1038/s41467-021-23038-7

    https://phys.org/news/2021-06-material-carbon-nanotubes-electricity...

  • Dr. Krishna Kumari Challa

    Physicists report definitive evidence how auroras are created

    The aurora borealis, or northern lights, that fill the sky in high-latitude regions have fascinated people for thousands of years. But how they're created, while theorized, had not been conclusively proven till recently.

    In a new study, a team of physicists  reports definitive evidence that the most brilliant auroras are produced by powerful electromagnetic waves during geomagnetic storms. The phenomena, known as Alfven waves, accelerate electrons toward Earth, causing the particles to produce the familiar atmospheric light show.

    The study, published online June 7 in the journal Nature Communications, concludes a decades-long quest to demonstrate experimentally the physical mechanisms for the acceleration of electrons by Alfven waves under conditions corresponding to Earth's auroral magnetosphere.

    Measurements revealed this small population of electrons undergoes 'resonant acceleration' by the Alfven wave's electric field, similar to a surfer catching a wave and being continually accelerated as the surfer moves along with the wave.

     Laboratory measurements of the physics of auroral electron acceleration by Alfvén waves, Nature Communications (2021). DOI: 10.1038/s41467-021-23377-5 , www.nature.com/articles/s41467-021-23377-5

  • Dr. Krishna Kumari Challa

    part 2:

    Scientists have known that energized particles that emanate from the sun—such as electrons racing at approximately 45 million miles per hour—precipitate along the Earth's magnetic field lines into the upper atmosphere, where they collide with oxygen and nitrogen molecules, kicking them into an excited state. These excited molecules relax by emitting light, producing the colorful hues of the aurora.

    The theory was supported by spacecraft missions that frequently found Alfven waves traveling Earthward above auroras, presumably accelerating electrons along the way. Although space-based measurements had supported the theory, limitations inherent to spacecraft and rocket measurements had prevented a definitive test.

    The physicists were able to find confirmatory evidence in a series of experiments conducted at the Large Plasma Device (LPD) in UCLA's Basic Plasma Science Facility, a national collaborative research facility supported jointly by the U.S. Department of Energy and National Science Foundation.

    https://phys.org/news/2021-06-physicists-definitive-evidence-aurora...

  • Dr. Krishna Kumari Challa

    Turning off lights can save migrating birds from crashing into buildings

    Every night during the spring and fall migration seasons, thousands of birds are killed when they crash into illuminated windows, disoriented by the light. But a new study in PNAS shows that darkening just half of a building's windows can make a big difference for birds. Using decades' worth of data and birds collected by Field Museum scientists at Chicago's McCormick Place convention center, the researchers found that on nights when half the windows were darkened, there were 11 times fewer bird collisions during spring migration and 6 times fewer collisions during fall migration than when all the windows were lit.

    This  research provides the best evidence yet that migrating birds are attracted to building lights, often causing them to collide with windows and die. And that turning off the lights can save the birds.

    Benjamin M. Van Doren el al., "Drivers of fatal bird collisions in an urban center," PNAS (2021). www.pnas.org/cgi/doi/10.1073/pnas.2101666118

    https://phys.org/news/2021-06-migrating-birds.html?utm_source=nwlet...

  • Dr. Krishna Kumari Challa

    Bacteriophages  prove to be more effective at fighting antibiotic resistance when trained

    The threat of antibiotic resistance rises as bacteria continue to evolve to foil even the most powerful modern drug treatments. By 2050, antibiotic resistant-bacteria threaten to claim more than 10 million lives as existing therapies prove ineffective.

    Bacteriophage, or "phage," have become a new source of hope against growing antibiotic resistance. Ignored for decades by western science, phages have become the subject of increasing research attention due to their capability to infect and kill bacterial threats.

    A new project  has provided evidence that phages that undergo special evolutionary training increase their capacity to subdue bacteria. Like a boxer in training ahead of a title bout, pre-trained phages demonstrated they could delay the onset of bacterial resistance.

    The trained phage had already experienced ways that the bacteria would try to dodge it. It had 'learned' in a genetic sense. It had already evolved mutations to help it counteract those moves that the bacteria were taking. Scientists are using phage's own improvement algorithm, evolution by natural selection, to regain its therapeutic potential and solve the problem of bacteria evolving resistance to yet another therapy.

    The researchers are now extending their findings to research how pre-trained phages perform on bacteria important in clinical settings, such as E. coli. They are also working to evaluate how well training methods work in animal models.

    Joshua M. Borin et al, Coevolutionary phage training leads to greater bacterial suppression and delays the evolution of phage resistance, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2104592118

    https://phys.org/news/2021-06-viruses-effective-antibiotic-resistan...

  • Dr. Krishna Kumari Challa

    World's first blood test for real-time monitoring of cancer treatme...

    Cancer patients who are undergoing targeted therapy can look forward to a new blood test that could tell their doctors whether the treatment is working, within one day after the start of the treatment. This will significantly speed up the evaluation process and enable doctors to make adjustments to the treatment plan, if necessary, to improve patients' chances of recovery.

    Sijun Pan et al, Extracellular vesicle drug occupancy enables real-time monitoring of targeted cancer therapy, Nature Nanotechnology (2021). DOI: 10.1038/s41565-021-00872-w

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    How coronavirus aerosols travel through lungs

    More than 65% of inhaled coronavirus particles reach the deepest region of our lungs where damage to cells can lead to low blood oxygen levels, new research has discovered, and more of these aerosols reach the right lung than the left.

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    Infrared imaging leaves invasive pythons nowhere to hide

    For more than 25 years, Burmese pythons have been living and breeding in the Florida Everglades, where they prey on native wildlife and disrupt the region's delicate ecosystems. A new study shows that infrared cameras could make it easier to spot these invasive snakes in the Florida foliage, providing a new tool in the effort to remove them.

  • Dr. Krishna Kumari Challa

    Studies reveal skull as unexpected source of brain immunity

    he immune system is the brain’s best frenemy. It protects the brain from infection and helps injured tissues heal, but it also causes autoimmune diseases and creates inflammation that drives neurodegeneration.

    Two new studies in mice suggest that the double-edged nature of the relationship between the immune system and the brain may come down to the origins of the immune cells that patrol the meninges, the tissues that surround the brain and spinal cord. In complementary studies published June 3 in the journal Science, two teams of researchers unexpectedly found that many of the immune cells in the meninges come from bone marrow in the skull and migrate to the brain through special channels without passing through the blood.

    These skull-derived immune cells are peacekeepers, dedicated to maintaining a healthy status quo. It’s the other immune cells, the ones that arrive from the bloodstream, that seem to be the troublemakers. They carry genetic signatures that mark them as likely to promote autoimmunity and inflammation, and they become more abundant with aging or under conditions of disease or injury. Taken together, the findings reveal a key aspect of the connection between the brain and the immune system that could inform our understanding of a wide range of brain disorders.

    1. Andrea Cugurra, Tornike Mamuladze, Justin Rustenhoven, Taitea Dykstra, Giorgi Beroshvili, Zev J. Greenberg, Wendy Baker, Zach Papadopoulos, Antoine Drieu, Susan Blackburn, Mitsuhiro Kanamori, Simone Brioschi, Jasmin Herz, Laura G. Schuettpelz, Marco Colonna, Igor Smirnov, Jonathan Kipnis. Skull and vertebral bone marrow are myeloid cell reservoirs for the meninges and CNS parenchyma. Science, 2021; eabf7844 DOI: 10.1126/science.abf7844

    https://researchnews.cc/news/7122/Studies-reveal-skull-as-unexpecte...

    https://www.sciencedaily.com/releases/2021/06/210603171058.htm

  • Dr. Krishna Kumari Challa

    Defying body clock linked to depression and lower wellbeing

    People whose sleep pattern goes against their natural body clock are more likely to have depression and lower levels of wellbeing, according to a largescale new study.

    This research also found the most robust evidence to date that being genetically programmed to be an early riser is protective against major depression, and improves wellbeing. Researchers suggest this may be because society is set up to be more aligned to early risers, through the standard 9-5 working pattern.

    Molecular Psychiatry (2021). www.nature.com/articles/s41380-021-01157-3

    https://medicalxpress.com/news/2021-06-defying-body-clock-linked-de...

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    Climate change is making ocean waves more powerful, threatening to ...

    Sea level rise isn't the only way climate change will devastate the coast. Our research, published today, found it is also making waves more powerful, particularly in the Southern Hemisphere.

  • Dr. Krishna Kumari Challa

    Scientists can predict which women will have serious pregnancy complications

    Women who will develop potentially life-threatening disorders during pregnancy can be identified early when hormone levels in the placenta are tested, a new study has shown.

    Pregnancy disorders affect around one in ten pregnant women. Nearly all of the organ systems of the mother's body need to alter their function during pregnancy so that the baby can grow. If the mother's body cannot properly adapt to the growing baby this leads to major and common issues including fetal growth restriction, fetal over-growth, gestational diabetes, and preeclampsia—a life-threatening high blood pressure in the mother.

    Many of these complications lead to difficult labors for women with more medical intervention and lifelong issues for the baby including diabetes, heart issues and obesity.

    Pregnancy disorders are usually diagnosed during the second or third trimester of gestation when they have often already had a serious impact on the health of the mother and baby. The current methods to diagnose pregnancy disorders are not sensitive or reliable enough to identify all at risk pregnancies.

    Now scientists have found a way to test hormone levels in the placenta to predict which women will have serious pregnancy complications.

    This study found hormonal biomarkers from the placenta could indicate which women would have pregnancy complications. We found that these biomarkers are present from the first trimester of pregnancy, normally women are only diagnosed with complications during the second or third trimester when disorders may already have had serious consequences for the health of the mother and her developing baby.

    Nature Communications Biology (2021). DOI: 10.1038/s42003-021-02214-x

    https://medicalxpress.com/news/2021-06-scientists-women-pregnancy-c...

  • Dr. Krishna Kumari Challa

    Subatomic particle seen changing to antiparticle and back

    Physicists have proved that a subatomic particle can switch into its antiparticle alter-ego and back again, in a new discovery revealed recently.

    The extraordinarily precise measurement was made by UK researchers using the Large Hadron Collider beauty (LHCb) experiment at CERN.

    It has provided the first evidence that charm mesons can change into their antiparticle and back again.

    For more than 10 years, scientists have known that charm mesons, subatomic particles that contain a quark and an antiquark, can travel as a mixture of their particle and antiparticle states.

    It is a phenomenon called mixing.

    However, this new result shows for the first time that they can oscillate between the two states.

    Armed with this new evidence, scientists can try to tackle some of the biggest questions in physics around how particles behave outside of the Standard Model.

    One being, whether these transitions are caused by unknown particles not predicted by the guiding theory.

    The research, submitted to Physical Review Letters and available on arXiv.

    Observation of the mass difference between neutral charm-meson eigenstates. arXiv:2106.03744v1 [hep-ex] arxiv.org/abs/2106.03744

    https://phys.org/news/2021-06-subatomic-particle-antiparticle.html?...

  • Dr. Krishna Kumari Challa

    Why Arctic soil can go slip-sliding away

    Slow-moving arctic soils form patterns that, from a distance, resemble those found in common fluids such as drips in paint and birthday cake icing. Los Alamos researchers and their collaborators analyzed existing arctic soil formations and compared them to viscous fluids, determining that there is a physical explanation for this pattern that is common to both Earth and Mars landscapes.

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    Algae blooms harmful to aquaculture: UN global assessment

    Potentially lethal marine algae blooms have not increased in number over the last three decades, but pose a serious threat to aquaculture, according to a UN global assessment released recently.

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    Bacteria-sized robots take on microplastics and win by breaking the...

    Small pieces of plastic are everywhere, stretching from urban environments to pristine wilderness. Left to their own devices, it can take hundreds of years for them to degrade completely. Catalysts activated by sunlight could speed up the process, but getting these compounds to interact with microplastics is difficult. In a proof-of-concept study, researchers reporting in ACS Applied Materials & Interfaces developed self-propelled microrobots that can swim, attach to plastics and break them down.

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    Normal breathing sends saliva droplets 7 feet; masks shorten this

    The World Health Organization and the Centers for Disease Control recommend keeping a certain distance between people to prevent the spread of COVID-19. These social distancing recommendations are estimated from a variety of studies, but further research about the precise mechanism of virus transport from one person to another is still needed.

  • Dr. Krishna Kumari Challa

    Cloud Avalanche

    This "cloud avalanche" occurred near the Kapuche Glacier Lake in the mountains of Nepal last month. At that time, a group of travel companions were camping by the lake, and they took the risk of taking pictures of this rare visual feast. The white snow clouds rushed down the valley, unstoppable, instantly swallowing the mountains and hitting the lake surface. Against the backdrop of the blue sky and the yellow-brown mountains, they were more distinct, magnificent and shocking. The strong air flow overturned the tents and sleeping bags, frightening the travellers, but fortunately no casualties were reported. After that, a small rainbow appeared by the lake, which was extremely beautiful, and the travelers all cheered and marveled at it. Call it "perfect cloud collapse".

  • Dr. Krishna Kumari Challa

    Popularity runs in families

  • Dr. Krishna Kumari Challa

    Low Doses of "Laughing Gas" Could Be Fast, Effective Treatment for Severe Depression

  • Dr. Krishna Kumari Challa

    Bacteria-sized robots take on microplastics and win by breaking them down

    Small pieces of plastic are everywhere, stretching from urban environments to pristine wilderness. Left to their own devices, it can take hundreds of years for them to degrade completely. Catalysts activated by sunlight could speed up the process, but getting these compounds to interact with microplastics is difficult. In a proof-of-concept study, researchers reporting in ACS Applied Materials & Interfaces developed self-propelled microrobots that can swim, attach to plastics and break them down.

    While plastic products are omnipresent indoors, plastic waste and broken bits now litter the outdoors, too. The smallest of these—microplastics less than 5 mm in size—are hard to pick up and remove. In addition, they can adsorb heavy metals and pollutants, potentially harming humans or animals if accidently consumed. So, previous researchers proposed a low-energy way to get rid of plastics in the environment by using catalysts that use sunlight to produce highly reactive compounds that break down these types of polymers. However, getting the catalysts and tiny plastic pieces in contact with each other is challenging and usually requires pretreatments or bulky mechanical stirrers, which aren't easily scaled-up. so wanted to create a sunlight-propelled catalyst that moves toward and latches onto microparticles and dismantles them.

    To transform a catalytic material into light-driven microrobots, the researchers made star-shaped particles of bismuth vanadate and then evenly coated the 4–8 µm-wide structures with magnetic iron oxide. The microrobots could swim down a maze of channels and interact with microplastic pieces along their entire lengths. The researchers found that under visible light, microrobots strongly glommed on to four common types of plastics. The team then illuminated pieces of the four plastics covered with the microrobot catalyst for seven days in a dilute hydrogen peroxide solution. They observed that the plastic lost 3% of its weight and that the surface texture for all types changed from smooth to pitted, and small molecules and components of the plastics were found in the left-over solution. The researchers say the self-propelled microrobot catalysts pave the way toward systems that can capture and degrade microplastics in hard-to-reach-locations.

    Seyyed Mohsen Beladi-Mousavi et al, A Maze in Plastic Wastes: Autonomous Motile Photocatalytic Microrobots against Microplastics, ACS Applied Materials & Interfaces (2021). DOI: 10.1021/acsami.1c04559

    https://phys.org/news/2021-06-bacteria-sized-robots-microplastics.h...

  • Dr. Krishna Kumari Challa

    Researchers create quantum microscope that can see the impossible

    In a major scientific leap,  researchers have created a quantum microscope that can reveal biological structures that would otherwise be impossible to see.

    This paves the way for applications in biotechnology, and could extend far beyond this into areas ranging from navigation to medical imaging.

    The microscope is powered by the science of quantum entanglement, an effect Einstein described as "spooky interactions at a distance".

    The quantum entanglement in this microscope provides 35 percent improved clarity without destroying the cell, allowing us to see minute biological structures that would otherwise be invisible.

    "The benefits are obvious—from a better understanding of living systems, to improved diagnostic technologies.

     Quantum-enhanced nonlinear microscopy, Nature (2021). DOI: 10.1038/s41586-021-03528-w , www.nature.com/articles/s41586-021-03528-w

    https://phys.org/news/2021-06-quantum-microscope-impossible.html?ut...

  • Dr. Krishna Kumari Challa

    Scientists Have Calculated The Weight of All The SARS-CoV-2 in The World

    If all the SARS-CoV-2 particles currently circulating in humans around the globe were gathered together into one place, they would weigh somewhere between the weight of an apple and that of a young toddler, according to a new study.

    A group of researchers recently calculated that each infected individual carries about 10 billion to 100 billion individual SARS-CoV-2 particles at the peak of their infection. That suggests that all of the SARS-CoV-2 viruses currently infecting people around the world — which has been about 1 million to 10 million infections at any given time during the course of the pandemic  — have a collective mass of somewhere between 0.22 and 22 pounds (0.1 and 10 kilograms).

    Small doesn't mean insignificant, however.

    Here we are talking about a super-tiny mass of viruses, and they are completely wreaking havoc on the world.

    The total number and mass of SARS-CoV-2 virions

    https://www.pnas.org/content/118/25/e2024815118/tab-article-info

    https://www.sciencealert.com/how-much-does-all-the-sars-cov-2-in-th...

  • Dr. Krishna Kumari Challa

  • Dr. Krishna Kumari Challa

    'Vegan spider silk' provides sustainable alternative to single-use plastics

    Researchers have created a plant-based, sustainable, scalable material that could replace single-use plastics in many consumer products.

    The researchers, from the University of Cambridge, created a polymer film by mimicking the properties of spider silk, one of the strongest materials in nature. The new material is as strong as many common plastics in use today and could replace plastic in many common household products.

    The material was created using a new approach for assembling plant proteins into materials which mimic silk on a molecular level. The energy-efficient method, which uses sustainable ingredients, results in a plastic-like free-standing film, which can be made at industrial scale. Non-fading 'structural' color can be added to the polymer, and it can also be used to make water-resistant coatings.

    The material is home compostable, whereas other types of bioplastics require industrial composting facilities to degrade.

    Nature Communications (2021). DOI: 10.1038/s41467-021-23813-6

    https://phys.org/news/2021-06-vegan-spider-silk-sustainable-alterna...

  • Dr. Krishna Kumari Challa

    How cells measure themselves

    Ever since scientists discovered cells under the microscope more than 350 years ago, they have noted that each type of cell has a characteristic size. From tiny bacteria to inches-long neurons, size matters for how cells work. The question of how these building blocks of life regulate their own size, however, has remained a mystery.

    Now we have an explanation for this long-standing biological question. In a study focusing on the growing tip of plants, researchers show that cells use their DNA content as an internal gauge to assess and adjust their size.

    "Cell size controlled in plants using DNA content as an internal scale" Science (2021). science.sciencemag.org/cgi/doi … 1126/science.abb4348

    https://phys.org/news/2021-06-cells.html?utm_source=nwletter&ut...

    How cells measure themselves 

  • Dr. Krishna Kumari Challa

    Hydrogen sulfide critical to innate ability of bacteria to survive antibiotics

    The signaling molecule hydrogen sulfide (H2S) plays a critical role in antibiotic tolerance, the innate ability of bacteria to survive normally lethal levels of antibiotics, a new study finds.

    the study revolves around tolerance, wherein bacteria in general have evolved to use common defense systems to resist antibiotics. Tolerance differs from antibiotic resistance, where one species happens to acquire a genetic change that helps them resist treatment.

    In one defense mechanism, tolerant bacteria, also called "persisters," stop multiplying (proliferating), reducing their energy use (metabolism) to survive antibiotic treatment, but resuming growth when the treatment ends. Persisters are particularly abundant in biofilms, bacterial colonies that live in tough polymeric matrices which further prevent their eradication.

    The combined trends toward resistant infections and fewer new antimicrobials are projected to kill 10 million people annually by the year 2050. New approaches are urgently needed to prevent this, and this  study suggests that suppressing bacterial H2S would make different antibiotics more potent.

    K. Shatalin el al., "Inhibitors of bacterial H2S biogenesis targeting antibiotic resistance and tolerance," Science (2021). science.sciencemag.org/cgi/doi … 1126/science.abd8377

    https://phys.org/news/2021-06-hydrogen-sulfide-critical-innate-abil...

  • Dr. Krishna Kumari Challa

    Researchers have turned transparent calcite into artificial gold

    In a breakthrough in metamaterials, for the first time in the world, researchers at Tel Aviv University have developed an innovative nanotechnology that transforms a transparent calcite nanoparticle into a sparkling gold-like particle. In other words, they turned the transparent particle into a particle that is visible despite its very small dimensions. According to the researchers the new material can serve as a platform for innovative cancer treatments.

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    Injectable microspheres to repair failing hearts

    Biodegradable microspheres can be used to deliver heart cells generated from stem cells to repair damaged hearts after a heart attack, according to new findings by UCL researchers. This type of cell therapy could one day cure debilitating heart failure, which affects an estimated 920,000 people in the UK and continues to rise as more people are surviving a heart attack than ever before.

  • Dr. Krishna Kumari Challa

    Nepal's unique lightning signature involves up to four strikes per flash

    While every lightning flash is unique in the way the discharge travels through the atmosphere, whether cloud-to-cloud, cloud-to-ground or the more esoteric sprites, halos, jets, and elves of the upper atmosphere. There are common features in these different types of lightning and for cloud-to-ground flashes, it has been assumed that there are two main types of flash known to meteorologists and atmospheric scientists—negative ground flashes and positive ground flashes.

    The difference between the negative and positive flash is simply that the polarity of the discharge reaching the ground in the lightning flash. Most (90 percent) cloud-to-ground flashes are negative ground flashes. Just 10 percent are positive. The positive ground flash involves a single stroke.

    A novel phenomenon has been found  in the sub-tropical, mountainous region of Nepal now.

    Researchers have used a simple circuit and antenna system to measure the electrical signature of lightning flashes in the Himalayan region and found that positive ground flashes there are unique. Instead of involving a single strike, lightning here involves up to four strikes per flash, or discharge.

    They explain that the lightning signature in this region is characterized by a relatively slow, negative electric field event preceded by a pronounced opposite-polarity pulse. The average duration of the main waveform was about 500 microseconds and the average duration of the preceding opposite-polarity pulses was approximately 40 microseconds. These figures are based on measurements of more than 5000 lightning flashes.

    A likely explanation may lie in the fact that Nepal has regions that are a mere 60 metres above sea level and then within just 160 kilometres we can figuratively scale the giddy heights of Mount Everest, the peak at 8848 metres above sea level. Moreover across this altitude gradient and through the course of the seasons, Nepal can have a temperature ranging from a balmy 30 degrees Celsius down to –50 Celsius. All such characteristics are unique of themselves and so it is perhaps no surprise that the lightning seen in this region is unique too.

    It is worth pointing out that lightening signatures not dissimilar to the unique flashes measured in Nepal have been seen occasionally in Sweden and Florida but not at anything like the frequency compared to other flashes seen in Nepal.

    Pitri Bhakta Adhikari, Unique lightning signatures observed from sub-tropical, mountainous country, Nepal, International Journal of Hydrology Science and Technology (2021). DOI: 10.1504/IJHST.2021.115488

    https://phys.org/news/2021-06-nepal-unique-lightning-signature-invo...