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'

Load Previous Comments
  • 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...

  • Dr. Krishna Kumari Challa

    A potentially safer, more effective gene therapy vector for blood disorders

    Researchers at Children's Hospital of Philadelphia (CHOP) have developed a gene therapy vector for blood disorders like sickle cell disease and beta-thalassemia that is potentially safer and more effective than those currently used in gene therapy trials for those conditions. The vector, an engineered vehicle for delivering functional copies of the hemoglobin gene to correct a genetic abnormality, leads to the production of more hemoglobin with a lower dose, minimizing the risk of toxic side effects.

    Breda L, Ghiaccio V, Tanaka N, Jarocha D, Ikawa Y, Abdulmalik O, Dong A, Casu C, Raabe TD, Shan X, Danet-Desnoyers GA, Doto AM, Everett J, Bushman FD, Radaelli E, Assenmacher CA, Tarrant JC, Hoepp N, Guzikowski V, Smith-Whitley K, Kwiatkowski JL, and Rivella S. "Lentiviral vector ALS20 yields high hemoglobin levels with low genomic integrations for treatment of beta-globinopathies," Molecular Therapy, online January 29, 2021. DOI: 10.1016/j.ymthe.2020.12.036

    https://medicalxpress.com/news/2021-01-potentially-safer-effective-...

  • Dr. Krishna Kumari Challa

    'Organs-on-a-chip' system sheds light on how bacteria in the human digestive tract may influence neurological diseases

    In many ways, our brain and our digestive tract are deeply connected. Feeling nervous may lead to physical pain in the stomach, while hunger signals from the gut make us feel irritable. Recent studies have even suggested that the bacteria living in our gut can influence some neurological diseases.

    Modeling these complex interactions in animals such as mice is difficult to do, because their physiology is very different from humans'. To help researchers better understand the gut-brain axis, MIT researchers have developed an "organs-on-a-chip" system that replicates interactions between the brain, liver, and colon.

    Using that system, the researchers were able to model the influence that microbes living in the gut have on both healthy brain tissue and tissue samples derived from patients with Parkinson's disease. They found that short-chain fatty acids, which are produced by microbes in the gut and are transported to the brain, can have very different effects on healthy and diseased brain cells.

    "While short-chain fatty acids are largely beneficial to human health, it 's observed that under certain conditions they can further exacerbate certain brain pathologies, such as protein misfolding and neuronal death, related to Parkinson's disease.

    The brain has many interactions with the digestive tract, which can occur via the enteric nervous system or through the circulation of immune cells, nutrients, and hormones between organs.

    "Human hysiomimetic model integrating microphysiological systems of the gut, liver and brain for studies of neurodegenerative diseases" Science Advances (2021). advances.sciencemag.org/lookup … .1126/sciadv.abd1707

    https://medicalxpress.com/news/2021-01-organs-on-a-chip-bacteria-hu...

  • Dr. Krishna Kumari Challa

    By changing their shape, some bacteria can grow more resilient to antibiotics

    New research demonstrates how certain types of bacteria can adapt to long-term exposure to antibiotics by changing their shape. The work was published in the journal Nature Physics.

    Adaptation is a fundamental biological process driving organisms to change their traits and behaviour to better fit their environment. While antibiotics have long helped people prevent and cure bacterial infections, many species of bacteria have increasingly been able to adapt to resist antibiotic treatments.

    When exposed to less than lethal doses of the antibiotic chloramphenicol over multiple generations, the researchers found that the bacteria dramatically changed their shape by becoming wider and more curved.

    These shape changes enable bacteria to overcome the stress of antibiotics and resume fast growth. 

    The researchers came to this conclusion by developing a theoretical model to show how these physical changes allow the bacteria to attain a higher curvature and lower surface-to-volume ratio, which would allow fewer antibiotic particles to pass through their cellular surfaces as they grow.

    This insight is of great consequence to human health and will likely stimulate numerous further molecular studies into the role of cell shape on bacterial growth and antibiotic resistance.

    Shiladitya Banerjee et al. Mechanical feedback promotes bacterial adaptation to antibiotics, Nature Physics (2021). DOI: 10.1038/s41567-020-01079-x

    https://phys.org/news/2021-01-bacteria-resilient-antibiotics.html?u...

  • Dr. Krishna Kumari Challa

    Dewdrops on a spiderweb reveal the physics behind cell structures

    As any cook knows, some liquids mix well with each other, but others do not. For example, when a tablespoon of vinegar is poured into water, a brief stir suffices to thoroughly combine the two liquids. However, a tablespoon of oil poured into water will coalesce into droplets that no amount of stirring can dissolve. The physics that governs the mixing of liquids is not limited to mixing bowls; it also affects the behavior of things inside cells. It's been known for several years that some proteins behave like liquids, and that some liquid-like proteins don't mix together. However, very little is known about how these liquid-like proteins behave on cellular surfaces.

    --

    How vitamins, steroids and potential antivirals might affect SARS-C...

    Evidence is emerging that vitamin D—and possibly vitamins K and A—might help combat COVID-19. A new study from the University of Bristol published in the journal of the German Chemical Society Angewandte Chemie has shown how they—and other antiviral drugs—might work. The research indicates that these dietary supplements and compounds could bind to the viral spike protein and so might reduce SARS-CoV-2 infectivity. In contrast, cholesterol may increase infectivity, which could explain why having high cholesterol is considered a risk factor for serious disease.

    --

    It's elemental: Ultra-trace detector tests gold purity

    Unless radon gas is discovered in a home inspection, most people remain blissfully unaware that rocks like granite, metal ores, and some soils contain naturally occurring sources of radiation. In most cases, low levels of radiation are not a health concern. But some scientists and engineers are concerned about even trace levels of radiation, which can wreak havoc on sensitive equipment. The semiconductor industry, for instance, spends billions each year to source and "scrub" ultra-trace levels of radioactive materials from microchips, transistors and sensitive sensors.

    --

    How lipids distribute proteins within cells

    Researchers have observed how lipids distribute proteins within cells, a discovery that could open the door to understanding the causes of protein transport related diseases, such as cancer or neurodegenerative diseases.

  • Dr. Krishna Kumari Challa

    Accurate drug dosages with proton traps

    Researchers have developed a proton trap that makes organic electronic ion pumps more precise when delivering drugs. The new technique may reduce drug side effects, and in the long term, ion pumps may help patients with symptoms of neurological diseases for which effective treatments are not available. The results have been published in Science Advances.

    Currently available drug delivery methods—mainly tablets and injections—place the drug in locations where it is not required. This can lead to side effects that harm the patient.

    Researchers are trying to control this. Recent discovery in this regard is a proton trap that makes the amount delivered even more precise.

    "An electronic proton-trapping ion pump for selective drug delivery" Science Advancesadvances.sciencemag.org/lookup … .1126/sciadv.abd8738

    https://phys.org/news/2021-01-accurate-drug-dosages-proton.html?utm...

  • Dr. Krishna Kumari Challa

    New technology to detect bitter almonds in real time

    Who hasn't at some point been chewing on an almond and tasted an unpleasant and unexpected aftertaste that has nothing to do with the taste we are used to from one of the most consumed nuts in the world? The culprit has a name: amygdalin, a diglucoside that, when in contact with enzymes present in saliva, breaks down into glucose, benzaldehyde (the cause of the bitter taste) and hydrogen cyanide.

    To reduce this unpleasant ''surprise," researchers have developed a method that can predict levels of the abovementioned amygdalin present in the nuts analyzed both with and without shells, as well as correctly classify sweet almonds and bitter ones on an industrial scale, something that has only been done with shelled nuts, individual kernels or ground nuts to date.

    The new system uses portable equipment based on near infrared spectroscopy (NIRS) technology, which can analyze large amounts of a product in situ in real time, without having to go into a lab. This technological application is "of great interest to the farming sector.

    This technology is especially useful in the early detection of possible fraud and in food authentication.

    Miguel Vega-Castellote et al, Exploring the potential of NIRS technology for the in situ prediction of amygdalin content and classification by bitterness of in-shell and shelled intact almonds, Journal of Food Engineering (2020). DOI: 10.1016/j.jfoodeng.2020.110406

    https://phys.org/news/2021-01-technology-bitter-almonds-real.html?u...

  • Dr. Krishna Kumari Challa

    Genes that dance to the circadian rhythm

    Scientists  have made breakthrough discoveries on the circadian clock and how it affects gene expression. Some of the findings suggest a biological underpinning for different behaviors in people, such as morning people, nappers, evening people, night owls etc.

    The study of circadian rhythms has grown into its own field: chronobiology. And given that a person's circadian rhythm seems to dictate when certain drugs must be taken in order to maximize their effects, a new branch of medicine has also emerged recently: chronopharmacology.

     Now scientists have carried out an extensive study using Drosophila to study how different genes in various tissues of the animal are regulated so that they "know" when to turn on and off during the course of a day, i.e. in function of the circadian clock.

    The study revealed three major points about the circadian rhythm.

    First, the scientists detected more than 1700 genes whose expression cycles under the control of the circadian clock, with only fourteen of those genes being the same across all tissues in the fruit fly.

    "At least two of these fourteen were so far uncharacterized and significantly impact several locomotor activity rhythms parameters.

    Second, that each individual may have its own circadian rhythm, which may explain the large range of human behaviors, such as morning people, nappers, evening people, night owls etc.

    The physiological clock in about a third of Drosophila lines significantly deviates from the "natural" time by more than three hours. And most of the lines showed a circadian expression variation only in one or two tissues.

    There seems to be an abundant, natural circadian asynchrony in molecular circadian rhythms between various tissues, which has to our knowledge not been observed before and which may have all kinds of physiological consequences in metabolic patterns, digestive fluctuations etc.

    Finally, that a small genetic mutation can disrupt an individual's "photoentrainment," which refers to the aligning of the circadian rhythm to the pattern of light and dark in its environment.

    "Extensive tissue-specific expression variation and novel regulators underlying circadian behavior" Science Advancesadvances.sciencemag.org/lookup … .1126/sciadv.abc3781

    https://phys.org/news/2021-01-genes-circadian-rhythm.html?utm_sourc...

  • Dr. Krishna Kumari Challa

    India's vaccine production capacity is best asset world has today, says UN chief

    Calling for India to play a major role in global vaccination campaign, United Nations Secretary-General Antonio Guterres recently termed the vaccine production capacity of India as the "best asset" that the world has today.

    India has gifted over 55 lakh doses of coronavirus vaccine to neighbouring countries. India plans to gift vaccines doses to Oman, CARICOM countries, Nicaragua, Pacific Island states.

    New Delhi plans to supply 1 crore or 10 million vaccine doses to Africa and 10 lakh to United Nations health workers under GAVI's (Global Alliance for Vaccines and Immunisation) COVAX facility.

    There is interest in many countries to access vaccine from India. India leads in democratisation of vaccines supplying to poor and developing countries unlike developed  countries.

    From 20th January 2021 onward, India has gifted over 55 lakh doses of coronavirus vaccines to our neighbouring countries and in the extended neighbourhood--1.5 lakh to Bhutan, 1 lakh to Maldives, Mauritius and Bahrain, 10 lakhs to Nepal, 20 lakhs to Bangladesh, 15 lakhs to Myanmar, 50,000 to Seychelles, 5 lakh to Sri Lanka. In the coming days, it plans to gift further quantity to Oman that is of 1 lakh doses, 5 lakh doses to CARICOM countries. 2 lakh to Nicaragua, 2 lakh doses to the Pacific island state.

    It also plans to commercially export coronavirus vaccine to Saudi Arabia, South Africa, Canada, Mongolia and other countries.

    https://health.economictimes.indiatimes.com/news/industry/indias-va...

  • Dr. Krishna Kumari Challa

    Scientists jump-start two people's brains after coma

    In 2016, a team of researchers reported that a 25-year-old man recovering from a coma had made remarkable progress following a treatment to jump-start his brain using ultrasound.

    Now they report that two more patients with severe brain injuries — both had been in what scientists call a long-term “minimally conscious state” — have made impressive progress thanks to the same technique. The results are published online in the journal Brain Stimulation.

    The paper notes that, of three people who received the treatment, one — a 58-year-old man who had been in a car accident five-and-a-half years prior to treatment and was minimally conscious — did not benefit. However, the other two did.

    One is a 56-year-old man who had suffered a stroke and had been in a minimally conscious state, unable to communicate, for more than 14 months. After the first of two treatments, he demonstrated, for the first time, the ability to consistently respond to two distinct commands — the ability to drop or grasp a ball, and the ability to look toward separate photographs of two of his relatives when their names were mentioned.

    He also could nod or shake his head to indicate “yes” or “no” when asked questions such as “Is X your name?” and “Is Y your wife’s name?” In the days following the second treatment, he also demonstrated, for the first time since the stroke, the ability to use a pen on paper and to raise a bottle to his mouth, as well as to communicate and answer questions.

    These behaviors are diagnostic markers of emergence from a disorder of consciousness.

    The other patient who improved is a 50-year-old woman who had been in even less of a conscious state for more than two-and-a-half years following cardiac arrest. In the days after the first treatment, she was able, for the first time in years, according to her family, to recognize a pencil, a comb and other objects.

    Both patients showed the ability to understand speech. What is remarkable is that both exhibited meaningful responses within just a few days of the intervention.

    The scientists used a technique called low-intensity focused ultrasound, which uses sonic stimulation to excite the neurons in the thalamus, an egg-shaped structure that serves as the brain’s central hub for processing. After a coma, thalamus function is typically weakened. Doctors use a device about the size of a saucer creates a small sphere of acoustic energy they can aim at different brain regions to excite brain tissue. The researchers placed the device by the side of each patient’s head and activated it 10 times for 30 seconds each in a 10-minute period. Each patient underwent two sessions, one week apart.

    The treatment appears to be well tolerated; the researchers saw no changes to the patients’ blood pressure, heart rate or blood oxygen levels, and no other adverse events.

    While the scientists are excited by the results, they emphasize that the technique is still experimental and likely will not be available to the public for at least a few years. 

    https://www.brainstimjrnl.com/article/S1935-861X(21)00009-7/fulltext

    https://newsroom.ucla.edu/releases/ucla-scientists-jump-start-brain...

    https://researchnews.cc/news/4841/Scientists-jump-start-two-people-...

  • Dr. Krishna Kumari Challa

    Major discovery helps explain coral bleaching

    Corals, like all animals, must eat to live. The problem is that most corals grow in tropical waters that are poor in nutrients, sort of like ocean deserts; it’s this lack of nutrients that makes the water around coral reefs so crystal clear. Because food is not readily available, corals have developed a remarkable feeding mechanism that involves a symbiotic relationship with single-celled algae. These algae grow inside the corals, using the coral tissue as shelter and absorbing the CO2 that the corals produce. In exchange, the algae provide corals with nutrients they produce through photosynthesis. These algae contain a variety of pigments, which give the coral reefs the colors they’re known for.

    Over the past 35 years, tropical oceans have experienced multiple major heat waves. Scientists have observed that during these episodes, the algae – stressed by the warmer temperatures – release compounds that are toxic to the coral, prompting the coral to expel the algae from their tissue. That means the corals lose their color and their primary food source, and then begin to starve. This is the process of coral bleaching. And it has been occurring more and more frequently, threatening the survival of many reefs, including Australia’s Great Barrier Reef. Bleached corals do not necessarily die; their symbiotic algae population can be reestablished if the conditions around a reef return to normal. But if the heat persists, or is aggravated by other factors like pollution, the coral becomes too weak to survive.

    In a paper published in the prestigious PNAS on 26 January, an international team of scientists  reveals a major discovery related to how the symbiotic relationship ends between the coral and algae.  Theyshowed for the first time that the coral starts to suffer from hunger long before the algae are expelled. The algae apparently stop providing sufficient nutrients while they are still inside the coral tissue.

    Scientists already knew that ocean warming is the main factor causing the symbiotic relationship to break down. But what the team now discovered was that the coral is already in a stressed state and lacking nutrients even before the algae begin releasing toxic compounds. The roots of the problem are much deeper than the scientists thought, and they involve an early breakdown of the metabolic exchanges in these fascinating organisms.

    Based on these findings, researchers can determine which environmental conditions other than temperature (such as water quality) stress the corals in a reef, and use this information to predict whether the reef will bleach.

    "Heat stress destabilizes symbiotic nutrient cycling in corals". Nils Rädecker, Claudia Pogoreutz, Hagen M. Gegner, Anny Cardenas, Florian Roth, Jeremy Bougoure, Paul Guagliardo, Christian Wild, Mathieu Pernice, Jean-Baptiste Raina, Anders Meibom, Christian R. Voolstra. PNAS, 26 January 2021.

    https://actu.epfl.ch/news/major-discovery-helps-explain-coral-bleac...

  • Dr. Krishna Kumari Challa

    Scientists use a novel ink to 3D print ‘bone’ with living cells

  • Dr. Krishna Kumari Challa

    A protein that can melt tumors discovered at Vanderbilt
     For the second time, cancer researchers at Vanderbilt have discovered a protein that when genetically manipulated to impede it from interacting with a gene responsible for cancer genesis effectively melts tumors in days. The article, MYC regulates ribosome biogenesis and mitochondrial gene expression programs through interaction with Host Cell Factor-1, was published in the journal eLIFE on Jan. 8.

    https://researchnews.cc/news/4842/A-protein-that-can-melt-tumors-di...

    **

  • Dr. Krishna Kumari Challa

    Wireless linkage of brains may soon go to human testing

  • Dr. Krishna Kumari Challa

    The physics behind tumor growth

    Researchers at Duke University have developed a predictive theory for tumor growth that approaches the subject from a new point of view. Rather than focusing on the biological mechanisms of cellular growth, the researchers instead use thermodynamics and the physical space the tumor is expanding into to predict its evolution from a single cell to a complex cancerous mass.

    The results appeared Jan. 15 in the journal Biosystems.

    The new work is based on the constructal law, which Bejan penned in 1996, that states that for a system to survive, it must evolve to increase its access to flow. For example, the human vascular system has evolved to provide blood flow through a network of a few large arteries and many small capillaries. River systems, tree branches and modern highway and road networks all reflect the same forces at work.

    In the paper researchers demonstrate how a tumor’s growth and internal reorganization as it grows are directly tied to its need to create greater access to flowing nutrients as well as conduits for removing refuse. They use these insights to predict the growth of cell clusters as a function of structure, and also to predict the critical cluster sizes that mark the transitions from one distinct configuration to the next.

    To validate their theory, the researchers compared their predictions with the measurements of several independent studies of cancerous and non-cancerous tumor growth patterns. The results show that their work provides a unifying perspective on the growth of cell clusters on the smallest scales as well as the large-scale dynamics of proliferating cells as described in phenomenological models.

    As the tumor grows, the flow systems get large enough to create visible currents through the vascularization of the tumor. The new theory reveals the physics behind these sorts of dramatic transitions and predict when they should happen.

    https://pratt.duke.edu/about/news/physics-tumor-growth

    “Cell and Extracellular Matrix Growth Theory and its Implications for Tumorigenesis,” T.J. Sauer, E. Samei, A. Bejan. Biosystems, Jan. 15, 2021. DOI: 10.1016/j.biosystems.2020.104331

  • Dr. Krishna Kumari Challa

    Geological phenomenon widening the Atlantic Ocean

    An upsurge of matter from deep beneath the Earth's crust could be pushing the continents of North and South America further apart from Europe and Africa, new research has found.

    The plates attached to the Americas are moving apart from those attached to Europe and Africa by four centimetres per year. In between these continents lies the Mid-Atlantic Ridge, a site where new plates are formed and a dividing line between plates moving to the west and those moving to the east; beneath this ridge, material rises to replace the space left by the plates as they move apart.

    Now a team of  seismologists  have found evidence of an upwelling in the mantle—the material between the Earth's crust and its core—from depths of more than 600 kilometres beneath the Mid Atlantic ridge, which could be pushing the plates from below, causing the continents to move further apart. Upwellings beneath ridges are typically thought to originate from much shallower depths of around 60 km.

    The findings, published in the journal Nature provide a greater understanding of plate tectonics which causes many natural disasters around the world, including earthquakes, tsunamis and volcanic eruptions.

    A thin mantle transition zone beneath the equatorial Mid-Atlantic Ridge, Nature (2021). DOI: 10.1038/s41586-020-03139-x , www.nature.com/articles/s41586-020-03139-x

    https://phys.org/news/2021-01-geological-phenomenon-widening-atlant...

  • Dr. Krishna Kumari Challa

    Mouse study: Gabapentin prevents harmful structural changes in spin...

    Research led by The Ohio State University Wexner Medical Center and College of Medicine found that the widely prescribed pain-relief drug gabapentin can prevent harmful structural changes in the injured spinal cords of mice, and also block cardiovascular changes and immune suppression caused by spinal cord injury.

    --

    Study provides insight into how the brain may have evolved

    Researchers from The University of Western Australia have uncovered evidence of an important genetic step in the evolution of the brain. The finding highlights how genetic events that took place in our fish-like ancestors play crucial roles in human brain biology today.

    --

    How vitamins, steroids and potential antivirals might affect SARS-C...

    Evidence is emerging that vitamin D—and possibly vitamins K and A—might help combat COVID-19. A new study from the University of Bristol published in the journal of the German Chemical Society Angewandte Chemie has shown how they—and other antiviral drugs—might work. The research indicates that these dietary supplements and compounds could bind to the viral spike protein and so might reduce SARS-CoV-2 infectivity. In contrast, cholesterol may increase infectivity, which could explain why having high cholesterol is considered a risk factor for serious disease.

  • Dr. Krishna Kumari Challa

    Using science to explain the mysterious Dyatlov Pass Incident

  • Dr. Krishna Kumari Challa

    Physics of snakeskin sheds light on sidewinding

    Most snakes get from one place  to another by bending their bodies into S-shapes and slithering forward headfirst. A few species, however—found in the deserts of North America, Africa and the Middle East—have an odder way of getting around. Known as "sidewinders," these snakes lead with their mid-sections instead of their heads, slinking sideways across loose sand.

    Scientists took a microscopic look at the skin of sidewinders to see if it plays a role in their unique method of movement. They discovered that sidewinders' bellies are studded with tiny pits and have few, if any, of the tiny spikes found on the bellies of other snakes.

    The specialized locomotion of sidewinders evolved independently in different species in different parts of the world, suggesting that sidewinding is a good solution to a problem. Understanding how and why this example of convergent evolution works may allow us to adapt it for our own needs, such as building robots that can move in challenging environments.

    This research bring together the physics of soft matter—flowable materials like sand—and organismal biology. The study shows how animals' surfaces interact with the flowable materials in their environments to get around. Insights from the research may lead to improvements in human technology.

    Most snakes tend to keep their bellies largely in contact with the ground as they slide forward, bending their bodies from their heads to their tails. A sidewinder, however, lifts its midsection off the ground, shifting it in a sideways direction.

    Previous studies have hypothesized that sidewinding may allow a snake to move better on sandy slopes.

    Part 1

  • Dr. Krishna Kumari Challa

    Part 2

    investigated whether sidewinders' skin might also play a role in their unique movement style.

    They focused on three species of sidewinders, all of them vipers, in residence at zoos: The sidewinder rattlesnake (Crotalus cerastes), found in the deserts of the Southwestern United States and northern Mexico; and the Saharan horned viper (Cerastes cerastes) and the Saharan sand viper (Cerastes vipera), both from the deserts of north Africa.

    Skins shed from the sidewinders were collected and scanned with atomic force microscopy, a technique that provides resolution at the atomic level, on the order of fractions of a nanometer. For comparison, they also scanned snake skins shed from non-sidewinders.

    As expected, the microscopy revealed tiny, head-to-tail pointing spikes on the skin of the non-sidewinders. Previous research had identified these micro spikes on a variety of other slithering snakes.

    The current study, however, found that the skin of sidewinders is different. The two African sidewinders had micro pits on their bellies and no spikes. The skin of the sidewinder rattlesnake was also studded with tiny pits, along with a few, much smaller, spikes—although far fewer spikes than those of the slithering snakes.

    The researchers created a mathematical model to test how these different structures affect frictional interactions with a surface. The model showed that head-to-tail pointing spikes enhance the speed and distance of forward undulation but are detrimental to sidewinding.

    The model also showed that the uniform, non-directional structure of the round pits enhanced sidewinding, but was not as efficient as spikes for forward undulation.

    The research provides snapshots at different points in time of convergent evolution—when different species independently evolve similar traits as a result of having to adapt to similar environments.

    Jennifer M. Rieser el al., "Functional consequences of convergently evolved microscopic skin features on snake locomotion," PNAS (2021). www.pnas.org/cgi/doi/10.1073/pnas.2018264118

    https://phys.org/news/2021-02-physics-snakeskin-sidewinding.html?ut...

  • Dr. Krishna Kumari Challa

    Marine organisms use previously undiscovered receptors to detect, respond to light

    Just as plants and animals on land are keenly attuned to the hours of sunlight in the day, life in the oceans follows the rhythms of the day, the seasons and even the moon. A new study finds the biological light switches that make this possible.

    Single-celled organisms in the open ocean use a diverse array of genetic tools to detect light, even in tiny amounts, and respond.

    If you look in the ocean environment, all these different organisms have this day-night cycle. They are very in tune with each other, even as they get moved around. How do they know when it's day? How do they know when it's night?

    By analyzing RNA filtered out of seawater samples collected throughout the day and night, the study identifies four main groups of photoreceptors, many of them new. This genetic activity uses light to trigger changes in the metabolism, growth, cell division, movements and death of marine organisms.

    The discovery of these new genetic "light switches" could also aid in the field of optogenetics, in which a cell's function can be controlled with light exposure. Today's optogenetic tools are engineered by humans, but versions from nature might be more sensitive or better detect light of particular wavelengths, the researchers think.

    Sacha N. Coesel el al., "Diel transcriptional oscillations of light-sensitive regulatory elements in open-ocean eukaryotic plankton communities," PNAS (2021). www.pnas.org/cgi/doi/10.1073/pnas.2011038118

    https://phys.org/news/2021-02-marine-previously-undiscovered-recept...

  • Dr. Krishna Kumari Challa

    Lactobacillus manipulates bile acids to create favorable gut environment

    New research  reveals that probiotic Lactobacillus bacteria use enzymes situationally to manipulate bile acids and promote their own survival in the gut. These findings further elucidate the complicated relationship between bile acids and gut bacteria and could eventually enable researchers to design lactobacilli with therapeutic properties, thereby engineering a healthier human gut environment.

    Bile acids are key players in digestion and overall gut health. Produced in the liver and released after we eat, these acids not only break down cholesterol and help regulate fat absorption, they also have a huge impact on what types of bacteria colonize the gut.

    As bile acids move through the gut, they are initially chemically modified through the addition of an amino acid (frequently glycine or taurine), creating a complex "conjugated" bile acid pool. Some gut bacteria have enzymes, called bile salt hydrolases (BSHs), which can cleave or "deconjugate" these amino acids from the bile acids, allowing other bacteria to further transform the bile acids as they continue through the colon. These transformations affect the bile acids' toxicity, which in turn affects the ability of different bacteria to survive in the gut.

    The assumed relationship was that probiotic bacteria like Lactobacillus have BSHs that just deconjugate the bile acid, rendering it less toxic and allowing the bacteria to survive.

    The interplay between bile and bacteria has a huge impact on their ability to live, thrive or die in a very competitive environment.

     Matthew H. Foley el al., "Lactobacillus bile salt hydrolase substrate specificity governs bacterial fitness and host colonization," PNAS (2021). www.pnas.org/cgi/doi/10.1073/pnas.2017709118

    --

    It was found that bile acid toxicity was not merely dependent upon whether the bile acid was conjugated or deconjugated by a BSH; rather, the relationships were dependent upon the type of bile acid, the bacteria being acted upon, and which BSH was present.

    https://phys.org/news/2021-02-lactobacillus-bile-acids-favorable-gu...

  • Dr. Krishna Kumari Challa

    Virtual conference CO2 emissions quantified in new study

    The virtual conferencing that has replaced large, in-person gatherings in the age of COVID-19 represents a drastic reduction in carbon emissions, but those online meetings still come with their own environmental costs, new research from the University of Michigan shows.

    The research offers a framework for analyzing and tallying the carbon emissions of an online conference based on factors that include everything from energy used by servers and monitors to the resources used to manufacture and distribute the computers involved.

    Individuals could skip features like gallery view, disable HD video and repair instead of replace computers to extend their useful lifetimes.

    Grant Faber. A framework to estimate emissions from virtual conferences, International Journal of Environmental Studies (2021). DOI: 10.1080/00207233.2020.1864190

    https://phys.org/news/2021-02-virtual-conference-co2-emissions-quan...

  • Dr. Krishna Kumari Challa

    A call for a global ban on lead paint

    Once lead paint is on a wall, it becomes an expensive problem to fix. In impoverished settings, be they neighborhoods in Philadelphia or developing nations globally, remediation can be prohibitively costly.

    Branches and treetops can reduce greenhouse gas emission from heavy...

    New research from University of Gävle shows that forest residues can generate large amounts of biofuel, and, in the long run, reduce greenhouse gas emission by 88-94% from heavy transport on Swedish roads.

    Water disinfection with ozone

    While chlorine and ultraviolet light are the standard means of disinfecting water, ozone is equally effective in killing germs. To date, ozone has only been used as an oxidation agent for treating water in large plants. Now, however, a project consortium from Schleswig-Holstein is developing a miniaturized ozone generator for use in smaller applications such as water dispensers or small domestic appliances. The Fraunhofer Institute for Silicon Technology ISIT has provided the sensor chip and electrode substrates for the electrolysis cell.

  • Dr. Krishna Kumari Challa

    A new treatment to help people with a spinal cord injury

  • Dr. Krishna Kumari Challa

    An origami-inspired medical patch for sealing internal injuries

    Many surgeries today are performed via minimally invasive procedures, in which a small incision is made and miniature cameras and surgical tools are threaded through the body to remove tumors and repair damaged tissues and organs. The process results in less pain and shorter recovery times compared to open surgery.

    While many procedures can be performed in this way, surgeons can face challenges at an important step in the process: the sealing of internal wounds and tears.

    The bioadhesives currently used in minimally invasive surgeries are available mostly as biodegradable liquids and glues that can be spread over damaged tissues. When these glues solidify, however, they can stiffen over the softer underlying surface, creating an imperfect seal. Blood and other biological fluids can also contaminate glues, preventing successful adhesion to the injured site. Glues can also wash away before an injury has fully healed, and, after application, they can also cause inflammation and scar tissue formation.

    Taking inspiration from origami, MIT engineers have now designed a medical patch that can be folded around minimally invasive surgical tools and delivered through airways, intestines, and other narrow spaces, to patch up internal injuries. The patch resembles a foldable, paper-like film when dry. Once it makes contact with wet tissues or organs, it transforms into a stretchy gel, similar to a contact lens, and can stick to an injured site.

    Given the limitations of current designs, the team aimed to engineer an alternative that would meet three functional requirements. It should be able to stick to the wet surface of an injured site, avoid binding to anything before reaching its destination, and once applied to an injured site resist bacterial contamination and excessive inflammation.

    The team's design meets all three requirements, in the form of a three-layered patch. The middle layer is the main bioadhesive, made from a hydrogel material that is embedded with compounds called NHS esters. When in contact with a wet surface, the adhesive absorbs any surrounding water and becomes pliable and stretchy, molding to a tissue's contours. Simultaneously, the esters in the adhesive form strong covalent bonds with compounds on the tissue surface, creating a tight seal between the two materials. 

    This could be used to repair a perforation from a coloscopy, or seal solid organs or blood vessels after a trauma or elective surgical intervention. Instead of having to carry out a full open surgical approach, one could go from the inside to deliver a patch to seal a wound at least temporarily and maybe even long-term.

    In contrast to existing surgical adhesives, the team's new tape is designed to resist contamination when exposed to bacteria and bodily fluids. Over time, the patch can safely biodegrade away. The team has published its results in the journal Advanced Materials.

    Sarah J. Wu et al. A Multifunctional Origami Patch for Minimally Invasive Tissue Sealing, Advanced Materials (2021). DOI: 10.1002/adma.202007667

    https://phys.org/news/2021-02-origami-inspired-medical-patch-intern...

  • Dr. Krishna Kumari Challa

    A new way to make wood transparent, stronger and lighter than glass

    A team of researchers at the University of Maryland, has found a new way to make wood transparent. In their paper published in the journal Science Advances, the group describes their process and why they believe it is better than the old process.

    Qinqin Xia et al. Solar-assisted fabrication of large-scale, patternable transparent wood, Science Advances (2021). DOI: 10.1126/sciadv.abd7342

    https://phys.org/news/2021-02-wood-transparent-stronger-lighter-gla...

    **

  • Dr. Krishna Kumari Challa

    Say goodbye to the dots and dashes to enhance optical storage media

    Innovators have created technology aimed at replacing Morse code with colored "digital characters" to modernize optical storage. They are confident the advancement will help with the explosion of remote data storage during and after the COVID-19 pandemic.

    Morse code has been around since the 1830s. The familiar dots and dashes system may seem antiquated given the amount of information needed to be acquired, digitally archived and rapidly accessed every day. But those same basic dots and dashes are still used in many optical media to aid in storage.

    A new technology developed at Purdue is aimed at modernizing the optical digital storage technology. Rather than using the traditional dots and dashes as commonly used in these technologies, the  innovators encode information in the angular position of tiny antennas, allowing them to store more data per unit area.

    The storage capacity greatly increases because it is only defined by the resolution of the sensor by which you can determine the angular positions of antennas. They mapped the antenna angles into colors, and the colors are decoded.

    This advancement allows for more data to be stored and for that data to be read at a quicker rate. The research is published in Laser & Photonics Reviews.

     Maowen Song et al, Enabling Optical Steganography, Data Storage, and Encryption with Plasmonic Colors, Laser & Photonics Reviews (2021). DOI: 10.1002/lpor.202000343

    https://phys.org/news/2021-02-goodbye-dots-dashes-optical-storage.h...

  • Dr. Krishna Kumari Challa

    Twisted van der Waals materials as a new platform to realize exotic...

    Researchers from the MPSD, the RWTH Aachen University and the Flatiron Institute, Columbia University (both in the U.S.) and part of the Max Planck—New York City Center for Non-equilibrium Quantum Phenomena have provided a fresh perspective on the potential of twisted van der Waals materials for realizing novel and elusive states of matter and providing a unique materials-based quantum simulation platform.

  • Dr. Krishna Kumari Challa

    Researchers map non-visible materials at nanoscale with ultrasound

    The increasing miniaturization of electrical components in industry requires a new imaging technique at the nanometre scale. Delft researcher Gerard Verbiest and ASML have developed a first proof-of-concept method that they now plan to further develop. The method uses the same principle as ultrasound scanning in pregnancies, but on a much, much smaller scale.

    Existing non-destructive imaging techniques for nanoelectronics, such as optical and electron microscopy, are not accurate enough or applicable to deeper structures. A well-known 3-D technique on a macro-scale is ultrasound. The advantage here is that it works for every sample. That makes ultrasound an excellent way of mapping the 3-D structure of a non-transparent sample in a non-destructive way." And yet, ultrasound technology at the nanoscale didn't exist yet. Indeed, the resolution of ultrasound imaging is strongly determined by the wavelength of the sound used, and that is typically around a millimeter.

    o improve this, ultrasound has already been integrated into an Atomic Force Microscope (AFM).

    AFM is a technique that allows you to scan and map out surfaces extremely accurately with a tiny needle. The advantage here is that it isn't the wavelength but the size of the tip of the AFM that determines the resolution. Unfortunately, at the frequencies used so far (1-10 MHz), the response of the AFM is small and unclear. We do see something, but it's not clear exactly what we're seeing. So the frequency of the sound used needed to be further increased, to the GHz range, and that's what these researchers have now done.

    They have achieved this  through photoacoustics. Using the photoacoustic effect allows you to generate extremely short sound pulses. Researchers have managed to integrate this technique into an AFM. With the tip of the AFM, they c ould focus the signal. 

    But there are certainly potential applications outside of electronics as well. You could use it in cell biology to make a detailed 3-D image of a single living cell, for example of the way mitochondria are folded in a cell. And in materials science, you could use it for research into heat transport in an amazing material such as graphene."

    https://phys.org/news/2021-02-non-visible-materials-nanoscale-ultra...

    **

  • Dr. Krishna Kumari Challa

    Why food sticks to nonstick frying pans

    Despite the use of nonstick frying pans, foods will sometimes get stuck to a heated surface, even if oil is used. The results can be very messy and unappetizing.

    Scientists at the Czech Academy of Sciences began an investigation of the fluid properties of oil on a flat surface, such as a frying pan. Their work, reported in Physics of Fluids, shows convection may be to blame for our stuck-on food.

    The experimental investigation used a nonstick pan with a surface comprised of ceramic particles. A video camera was placed above the pan as it was heated and used to measure the speed at which a dry spot formed and grew. Further experiments with a Teflon-coated pan showed the same.

    Researchers experimentally explained why food sticks to the center of the frying pan. This is caused by the formation of a dry spot in the thin sunflower oil film as a result of thermocapillary convection.

    When the pan is heated from below, a temperature gradient is established in the oil film. For common liquids, such as the sunflower oil used in the experiment, the surface tension decreases when temperature increases. A surface tension gradient is established, directed away from the center where the temperature is higher and toward the pan's periphery.

    This gradient sets up a type of convection known as thermocapillary convection, which moves oil outward. When the oil film in the middle becomes thinner than a critical value, the film ruptures.

    The researchers determined the conditions that lead to dry spots for both stationary and flowing films. These conditions include a decrease in the local film thickness below a critical size as well as the size of the deformed region falling below a number known as the capillary length.

    "To avoid unwanted dry spots, the following set of measures should be applied: increasing the oil film thickness, moderate heating, completely wetting the surface of the pan with oil, using a pan with a thick bottom, or stirring food regularly during cooking.

    The phenomenon also occurs in other situations, such as the thin liquid films used in fluid distillation columns or other devices that may have electronic components.

    "Dry spot formation or film rupture plays a negative role, resulting in sharp overheating of the electronic components. The results of this study may, therefore, have wider application.

    "On formation of dry spots in heated liquid films" Physics of Fluids (2021). DOI: 10.1063/5.0035547

    https://phys.org/news/2021-02-food-nonstick-pans.html?utm_source=nw...

  • Dr. Krishna Kumari Challa

    How do electrons close to Earth reach almost the speed of light?

    A new study found that electrons can reach ultra-relativistic energies for very special conditions in the magnetosphere when space is devoid of plasma.

    Recent measurements from NASA's Van Allen Probes spacecraft showed that electrons can reach ultra-relativistic energies flying at almost the speed of light.  Researchers  have revealed under which conditions such strong accelerations occur. They had already demonstrated in 2020 that during solar storm plasma waves play a crucial role for that. However, it was previously unclear why such high electron energies are not achieved in all solar storms. In the journal Science Advances, they now show that extreme depletions of the background plasma density are crucial.

    At ultra-relativistic energies, electrons move at almost the speed of light. Then the laws of relativity become most important. The mass of the particles increases by a factor ten, time is slowing down, and distance decreases. With such high energies, charged particles become most dangerous to even the best protected satellites. As almost no shielding can stop them, their charge can destroy sensitive electronics. Predicting their occurrence—for example, as part of the observations of space weather practiced at the GFZ—is therefore very important for modern infrastructure.

    This study shows that electrons in the Earth's radiation belt can be promptly accelerated locally to ultra-relativistic energies, if the conditions of the plasma environment—plasma waves and temporarily low plasma density—are right. The particles can be regarded as surfing on plasma waves. In regions of extremely low plasma density they can just take a lot of energy from plasma waves. Similar mechanisms may be at work in the magnetospheres of the outer planets such as Jupiter or Saturn and in other astrophysical objects.

     Hayley J. Allison et al, Gyroresonant wave-particle interactions with chorus waves during extreme depletions of plasma density in the Van Allen radiation belts, Science Advances (2021). DOI: 10.1126/sciadv.abc0380

    https://phys.org/news/2021-02-electrons-earth.html?utm_source=nwlet...

  • Dr. Krishna Kumari Challa

    Temperature, humidity, wind predict second wave of pandemic

    The 'second wave' of the coronavirus pandemic has resulted in much blame placed on a lack of appropriate safety measures. However, due to the impacts of weather, research suggests two outbreaks per year during a pandemic are inevitable.

    Though face masks, travel restrictions, and social distancing guidelines help slow the number of new infections in the short term, the lack of climate effects incorporated into epidemiological models presents a glaring hole that can cause long-term effects.

    Typical models for predicting the behavior of an epidemic contain only two basic parameters, transmission rate and recovery rate. These rates tend to be treated as constants, but  this is not actually the case. Temperature, relative humidity, and wind speed all play a significant role, so the researchers aimed to modify typical models to account for these climate conditions. They call their new weather-dependent variable the Airborne Infection Rate index.

    When they applied the AIR index to models of Paris, New York City, and Rio de Janeiro, they found it accurately predicted the timing of the second outbreak in each city, suggesting two outbreaks per year is a natural, weather-dependent phenomenon. Further, the behavior of the virus in Rio de Janeiro was markedly different from the behavior of the virus in Paris and New York, due to seasonal variations in the northern and southern hemispheres, consistent with real data.

    The authors emphasize the importance of accounting for these seasonal variations when designing safety measures.

    As temperatures rise and humidity falls, scientists expect another improvement in infection numbers, though they note that mask and distancing guidelines should continue to be followed with the appropriate weather-based modifications.

    Talib Dbouk and Dimitris Drikakis. Fluid dynamics and epidemiology: Seasonality and transmission dynamics. Physics of Fluids 33, 021901 (2021); doi.org/10.1063/5.0037640

    https://phys.org/news/2021-02-temperature-humidity-pandemic.html?ut...

  • Dr. Krishna Kumari Challa

    Venus flytraps found to produce magnetic fields

    The Venus flytrap (Dionaea muscipula) is a carnivorous plant that encloses its prey using modified leaves as a trap. During this process, electrical signals known as action potentials trigger the closure of the leaf lobes. An interdisciplinary team of scientists has now shown that these electrical signals generate measurable magnetic fields. Using atomic magnetometers, it proved possible to record this biomagnetism.

    The problem is that the magnetic signals in plants are very weak, which explains why it was extremely difficult to measure them with the help of older technologies.

    We know that in the human brain, voltage changes in certain regions result from concerted electrical activity that travels through nerve cells in the form of action potentials. Techniques such as electroencephalography (EEG), magnetoencephalography (MEG) and magnetic resonance imaging (MRI) can be used to record these activities and noninvasively diagnose disorders. When plants are stimulated, they also generate electrical signals, which can travel through a cellular network analogous to the human and animal nervous system.

    Researchers have now demonstrated that electrical activity in the Venus flytrap is also associated with magnetic signals.The action potentials in a multicellular plant system produce measurable magnetic fields, something that had never been confirmed before.

    The trap of Dionaea muscipula consists of bilobed trapping leaves with sensitive hairs, which, when touched, trigger an action potential that travels through the whole trap. After two successive stimuli, the trap closes and any potential insect prey is locked inside and subsequently digested. Interestingly, the trap is electrically excitable in a variety of ways: in addition to mechanical influences such as touch or injury, osmotic energy, for example salt-water loads, and thermal energy in the form of heat or cold can also trigger action potentials. For their study, the research team used heat stimulation to induce action potentials, thereby eliminating potentially disturbing factors such as mechanical background noise in their magnetic measurements.

    While biomagnetism has been relatively well-researched in humans and animals, so far very little equivalent research has been done in the plant kingdom, using only superconducting-quantum-interference-device (SQUID) magnetometers, bulky instruments which must be cooled to cryogenic temperatures. For the current experiment, the research team used atomic magnetometers to measure the magnetic signals of the Venus flytrap. The sensor is a glass cell filled with a vapor of alkali atoms, which react to small changes in the local magnetic-field environment. These optically pumped magnetometers are more attractive for biological applications because they do not require cryogenic cooling and can also be miniaturized.

    The researchers detected magnetic signals with an amplitude of up to 0.5 picotesla from the Venus flytrap, which is millions of times weaker than the Earth's magnetic field. "The signal magnitude recorded is similar to what is observed during surface measurements of nerve impulses in animals.

    Anne Fabricant et al. Action potentials induce biomagnetic fields in carnivorous Venus flytrap plants, Scientific Reports (2021). DOI: 10.1038/s41598-021-81114-w

    https://phys.org/news/2021-02-venus-flytraps-magnetic-fields.html?u...

  • Dr. Krishna Kumari Challa

    Economic growth has 'devastating cost to nature', review finds

    Humanity's unbridled growth in recent decades has come at a "devastating cost to nature" according a wide-ranging international review on the vital economic role played by our living planet.

    --

    Why keeping one mature street tree is far better for humans and nat...

    Thanks to Victorian street planners, many British streets were designed to be full of big trees and, with 84% of the population living in urban areas, most people are more likely to encounter trees in the streets than they are in forests.

    --

    Scientists advocate breaking laws—of geography and ecology

    Recent global calamities—the pandemic, wildfires, floods—are spurring interdisciplinary scientists to nudge aside the fashionable First Law of Geography that dictates "everything is related to everything else, but near things are more related than distant things."

    --

    Scientists develop method to detect fake news

    Social media is increasingly used to spread fake news. The same problem can be found on the capital market—criminals spread fake news about companies in order to manipulate share prices. Researchers at the Universities of Göttingen and Frankfurt and the Jožef Stefan Institute in Ljubljana have developed an approach that can recognize such fake news, even when the news content is repeatedly adapted. The results of the study were published in the Journal of the Association for Information Systems.

  • Dr. Krishna Kumari Challa

    Why Do These Deadly Insects Look Like Flowers?

  • Dr. Krishna Kumari Challa

    Scientists uncover potential antiviral treatment for COVID-19

    Researchers from the University of Nottingham have discovered a novel antiviral property of a drug that could have major implications in how future epidemics / pandemics—including COVID-19—are managed.

    The study, published in Viruses, shows that thapsigargin is a promising broad spectrum antiviral, highly effective against COVID-19 virus (SARS-CoV-2), a common cold coronavirus, respiratory syncytial virus (RSV) and the influenza A virus.

    Given that acute respiratory virus infections caused by different viruses are clinically indistinguishable on presentation, an effective broad-spectrum that can target different virus types at the same time could significantly improve clinical management. An antiviral of this type could potentially be made available for community use to control active infection and its spread.

    The key features based on cell and animal studies, which make thapsigargin a promising antiviral are that it is:

    • effective against viral infection when used before or during active infection
    • able to prevent a virus from making new copies of itself in cells for at least 48 hours after a single 30-minute exposure.
    • stable in acidic pH, as found in the stomach, and therefore can be taken orally, so could be administered without the need for injections or hospital admission.
    • not sensitive to virus resistance.
    • at least several hundred-fold more effective than current antiviral options.
    • just as effective in blocking combined infection with coronavirus and influenza A virus as in single-virus infection.
    • safe as an antiviral (a derivative of thapsigargin has been tested in prostate cancer).

    https://medicalxpress.com/news/2021-02-scientists-uncover-potential...

    **