Excessive use of sanitisers could erase your fingerprints: Experts
Experts are reporting cases where sanitisers are “wiping off” fingerprints along with the Covid-19 virus. Experts blamed the nature of alcohol for the phenomenon.
A lady reported: If you value your fingerprints, don’t over-sanitise. Nehal Mistry, a bank professional, learned this the hard way when the office biometric attendance machine failed to recognise her fingerprints.
The Bopal resident used to sanitise her hands at least six-seven times a day. “Even my home security system could not read my fingerprints. I was already receiving treatment for a skin problem. So, my dermatologist asked me to reduce the use of alcohol-based sanitiser and shift to soap-based cleaning. She also prescribed a few ointments. It worked, and I got my fingerprints back.”
Experts from the city are reporting cases where sanitisers are “wiping off” fingerprints along with the Covid-19 virus. Experts blamed the nature of alcohol for the phenomenon. The condition is temporary, but it can happen to people using sanitisers excessively or not using moisturisers enough, they added.
Due to the use of sanitisers and other hand rubs, there is abrasion of the skin’s upper layer (epidermis). The fingerprints are formed due to the ridges in this layer. The abrasions change it and a clear image is not formed. Edema (swelling) and contact dermatitis also affect the fingerprint pattern.
The issue is however not very common, assure experts. The issue with fingerprints is reported more in those with an existing history of hyperhidrosis (excessive sweating). Frequent use of sanitisers coupled with other skin issues can increase peeling of epidermis.
It is clear that coronavirus vaccines are safe and effective, but as more are rolled out, researchers are learning about the extent and nature of side effects.
The two messenger-RNA (mRNA) vaccines, made by Moderna and Pfizer–BioNTech, seem to cause similar reactions. A significant portion of people experience non-serious reactions, such a sore arm or a headache. That proportion is larger than the one for the annual flu shot — perhaps because the mRNA COVID-19 vaccines generate a particularly strong immune response.
A tiny number of people have experienced severe allergic reactions to the vaccines. These are extremely rare and no one has died. Fewer than five people per million doses administered of the Moderna or Pfizer–BioNTech experienced anaphylactic reactions. That is based on self-reported data from health-care workers and vaccinated individuals. For the Oxford–AstraZeneca vaccine, 30 cases of anaphylaxis have been confirmed so far, out of a little more than 3 million administered doses.
Some researchers have had their eye on polyethylene glycol (PEG) as the anaphylaxis-causing agent in the mRNA vaccines. More research is needed.
No deaths have been directly attributed to a COVID-19 jab. But it’s very hard to definitively link a death that happens days or weeks after the vaccine — especially among recipients who are very old or have serious health conditions.
Safety data for some other widely used shots, such as the Chinese CoronaVac vaccine or the Russian Sputnik V vaccine, are harder to come by.
Scientists entered people’s dreams and got them ‘talking’
Because Lucid dreamers can hear and answer questions while still asleep, scientists find.
Scientists have successfully "talked" to a sleeping person in real-time by invading their dreams, a new study shows. The researchers say it's like trying to communicate with an astronaut on another world.
Dreamers can follow instructions, solve simple math problems and answer yes-no questions without ever waking up, according to the results of four experiments described Thursday (Feb. 18) in the journalCurrent Biology.
The researchers communicated directly with sleeping participants by asking them questions and having them respond with eye or facial movements during lucid dreams — when people are at minimum aware that they are dreaming. (Some lucid dreamers can control what happens in their dreams.)
Studying dreams is difficult because people often forget or distort details after waking up. That's in part because the brain doesn't form many newmemorieswhile sleeping and has a limited capacity to accurately store information after the dream has ended,according to the study.
To overcome this limitation, the researchers attempted to communicate with people while they were still dreaming. Because the study participants were having lucid dreams, that meant they could make a conscious effort to respond to cues coming in from the outside world, the researchers hypothesized.
Researchers placed electrodes on the participants' heads, to measure their brainwaves; next to their eyes, to track eye movements; and on their chin, to measure muscle activity. They used this data to determine when the participants entered the rapid eye movement (REM) stage of sleep, when lucid dreams are most likely to occur.
The researchers used several techniques across the experiments to communicate with dreamers during REM sleep, including asking them spoken questions and giving them encoded messages in flashing lights, beeping tones and physical taps, that the dreamers had been trained to decipher. If dreamers received and understood the question or message during a lucid dream, they then responded with a set of distinctive eye or facial movements that were interpreted by the electrodes.
"Such two-way communication — from outside to inside the dream and back out again — is something that may seem to belong to the domain of science fiction.
Metabolic mutations help bacteria resist drug treatment
Bacteria have many ways to evade the antibiotics that we use against them.
Most of the mutations known to confer resistance occur in the genestargeted by a particular antibiotic. Other resistance mutations allow bacteriato break down antibioticsor pump them out through their cell membranes.
Researchers have now identified another class of mutations that helps bacteria develop resistance. In a study of E. coli, they discovered that mutations to genes involved in metabolism can also help bacteria to evade the toxic effects of several different antibiotics. The findings shed light on a fundamental facet of how antibiotics work, and suggest potential new avenues for developing drugs that could enhance the effectiveness of existing antibiotics.
This study gives us insights into how we can boost the effectiveness of existing antibiotics because it emphasizes that downstream metabolism plays an important role. Specifically, the work indicates that the killing efficacy of an antibiotic can be enhanced if one can elevate the metabolic response of the treated pathogen. By turning down their metabolism after drug treatment, bacteria can prevent the buildup of harmful byproducts.
The findings raise the possibility that forcing bacteria into a heightened metabolic state could increase the effectiveness of existing antibiotics, the researchers say.
Scientists identify over 140,000 virus species in the human gut
Viruses are the most numerous biological entities on the planet. Now researchers have identified over 140,000 viral species living in the human gut, more than half of which have never been seen before.
The paper, published today (18 February 2021) inCell, contains an analysis of over 28,000 gut microbiome samples collected in different parts of the world. The number and diversity of the viruses the researchers found was surprisingly high, and the data opens up new research avenues for understanding how viruses living in the gut affecthuman health.
The human gut is an incredibly biodiverse environment. In addition to bacteria, hundreds of thousands of viruses called bacteriophages, which can infect bacteria, also live there.
It is known that imbalances in our gut microbiome can contribute to diseases and complex conditions such as Inflammatory Bowel Disease, allergies and obesity. But relatively little is known about the role our gut bacteria, and the bacteriophages that infect them, play in human health and disease.
Using a DNA-sequencing method called metagenomics, researchers at the Wellcome Sanger Institute and EMBL's European Bioinformatics Institute (EMBL-EBI) explored and catalogued the biodiversity of the viral species found in 28,060 public human gut metagenomes and 2,898 bacterial isolate genomes cultured from the human gut.
The analysis identified over 140,000 viral species living in the human gut, more than half of which have never been seen before.
Camarillo-Guerrero, L.F., et al. (2021). Massive expansion of human gut bacteriophage diversity. Cell. DOI: doi.org/10.1016/j.cell.2021.01.029
Physics of tumours: Cancer cells become fluidised and squeeze through tissue
Researchers have achieved a breakthrough in research into how cancer cells spread. They demonstrated for the first time how cells deform in order to move in dense tumor tissues and squeeze past neighboring cells. The researchers found that motile cells work together to fluidise tumour tissue.
These first observations of a phase transition in human tumours change our basic concepts of tumour progression and could improve cancer diagnosis and therapy.
the research showed that human tumours contain solid and fluid cell clusters, which would be a breakthrough in scientists' understanding of tumour mechanics.
Steffen Grosser et al, Cell and Nucleus Shape as an Indicator of Tissue Fluidity in Carcinoma, Physical Review X (2021). DOI: 10.1103/PhysRevX.11.011033
Using state-of-the-art plasma technology to make cheap fertilizer for small farmers may sound like magic, but it has now become reality. Researchers have built a small plasma-powered plant that produces nitrogen-based liquid fertilizer only using sun, water and air. The plant is easy to set up, sustainable and very efficient.
"The Queen's Gambit," the recent TV mini-series about a chess master, may have stirred increased interest in chess, but a word to the wise: social media talk about game-piece colors could lead to misunderstandings, at least for hate-speech detection software.
Researchers observe stationary Hawking radiation in an analog black hole
Black holes are regions in space where gravity is very strong—so strong that nothing that enters them can escape, including light. Theoretical predictions suggest that there is a radius surrounding black holes known as the event horizon. Once something passes the event horizon, it can no longer escape a black hole, as gravity becomes stronger as it approaches its center.
Theoretical physicist Stephen Hawking predicted that while nothing can escape from within them, black holes spontaneously emit a limited amount of light, which is known as Hawkingradiation. According to his predictions, this radiation is spontaneous (i.e., it arises from nothing) and stationary (i.e., its intensity does not change much over time).
Researchers at Technion- Israel Institute of Technology have recently carried out a study aimed at testing Hawking's theoretical predictions. More specifically, they examined whether the equivalent of Hawking radiation in an "artificial black hole" created in a laboratory setting was stationary.
If you go inside the event horizon there's no way to get out, even for light. Hawking radiation starts just outside the event horizon, where light can barely escape. That is really weird because there's nothing there; it's empty space. Yet this radiation starts from nothing, comes out, and goes towards Earth.
The Hawking radiation emitted by this analog black hole is made of sound waves, rather than light waves. The rubidium atoms flow faster than the speed of sound, so sound waves cannot reach the event horizon and escape from the black hole. Outside of the event horizon, however, the gas flows slowly, so sound waves can move freely.
According to Hawking's predictions, the radiation emitted by black holes is spontaneous. In one of their previous studies, Researchers were able to confirm this prediction in their artificial black hole. In their new study, they set out to investigate whether the radiation emitted by their black hole is also stationary (i.e., if it remains constant over time).
A black hole is supposed to radiate like a black body, which is essentially a warm object that emits a constant infrared radiation (i.e., black body radiation). Hawking suggested that black holes are just like regular stars, which radiate a certain type of radiation all the time, constantly. That's what they wanted to confirm in our study, and they did.
Observation of stationary spontaneous Hawking radiation and the time evolution of an analog black hole. Nature Physics(2021). DOI: 10.1038/s41567-020-01076-0
Spina bifida can be caused by uninherited genetic mutations
Genetic mutations which occur naturally during the earliest stages of an embryo's development can cause the severe birth defect spina bifida, finds a new experimental study in mice.
The research explains for the first time how a 'mosaic mutation' - a mutation which is not inherited from either parent (either via sperm or egg cell) but occurs randomly during cell divisions in the developing embryo—causes spina bifida.
Scientists
found that when a mutation in the gene Vangl2 (which contains information needed to create spinal cord tissue) was present in 16% of developing spinal cord cells of mouse embryos, this was sufficient to produce spina bifida.
Researchers say the findings add to scientists' understanding of how and why mosaicmutationscan affect and disruptcell function, including those of neighbouring cells, helping cause birth defects.
For parents, the findings may help reduce the burden felt by those who believe their child inherited spina bifida from them via genes, and believe future children could also inherit the condition. This is often discussed during genetic counselling.
Cell non-autonomy amplifies disruption of neurulation by mosaic Vangl2 deletion in mice, Nature Communications (2021). DOI: 10.1038/s41467-021-21372-4
People who don't suffer in cold have a genetic mutation to tolerate cold better
A new research has identified a specific genetic mutation that makes a fifth of us more resilient to cold conditions.
The genetic mutation in question stops the production of the proteinα-actinin-3, which is important for skeletal muscle fibre: The protein is only found in fast-twitch (or white) fibres and not in slow-twitch (or red) fibres.
Based on the new study's results, people without α-actinin-3 have a higher proportion of slow-twitch fibres, and one of the consequences is that the body tends to conserve energy by building up muscle tone through contractions rather than shivering.
This suggests that people lacking α-actinin-3 are better at keeping warm and, energy-wise, at enduring a tougher climate. The loss of this protein gives a greater resilience to cold .
Common agricultural pesticide may be putting hummingbirds at risk: U of T study
Hummingbirds need an incredible amount of energy to flap their wings 50 times per second to maintain hovering flight. Their metabolism is so supercharged that if they were human-sized they would consume energy at a rate more than 10 times that of an Olympic marathon runner. But a new University of Toronto study has found that a common agricultural pesticide, which is related to nicotine in tobacco and might be slowing down the crucial physiological process that makes hummingbirds so unique upto 25% in the hours after exposure.
Lab-grown 'mini-bile ducts' used to repair human livers in regenerative medicine first
The research paves the way for cell therapies to treat liver disease – in other words, growing ‘mini-bile ducts’ in the lab as replacement parts that can be used to restore a patient’s own liver to health – or to repair damaged organ donor livers, so that they can still be used for transplantation.
Bile ducts act as the liver’s waste disposal system, and malfunctioning bile ducts are behind a third of adult and 70 per cent of children’s liver transplantations, with no alternative treatments. There is currently a shortage of liver donors: This means that only a limited number of patients can benefit from this therapy.
Approaches to increase organ availability or provide an alternative to whole organ transplantation are urgently needed. Cell-based therapies could provide an advantageous alternative. However, the development of these new therapies is often impaired and delayed by the lack of an appropriate model to test their safety and efficacy in humans before embarking in clinical trials.
Now, in a study published in Science, scientists have developed a new approach that takes advantage of a recent ‘perfusion system’ that can be used to maintain donated organs outside the body. Using this technology, they demonstrated for the first time that it is possible to transplant biliary cells grown in the lab known as cholangiocytes into damaged human livers to repair them. As proof-of-principle for their method, they repaired livers deemed unsuitable for transplantation due to bile duct damage. This approach could be applied to a diversity of organs and diseases to accelerate the clinical application of cell-based therapy.
This video allows us to see, for the first time, how small circles of DNA adopt dance-like movements inside a cell. Being able to observe DNA in such detail could help to accelerate the development of new gene therapies.
Engineers have created a four-legged soft robot that doesn’t need any electronics to work. The robot only needs a constant source of pressurized air for all its functions, including its controls and locomotion systems.
No more popping pills, now just inhale your antibiotics!
You may not have to pop up azithromycin pills in the future. Instead, you will be able to simply inhale this most common antibiotic drug widely prescribed to treat respiratory tract infections of the nose, throat and lungs.
You may not have to pop up azithromycin pills in the future. Instead, you will be able to simply inhale this most common antibiotic drug widely prescribed to treat respiratory tract infections of the nose, throat and lungs.
Researchers of M S University’s Faculty of Pharmacy have received a patent for their invention of a liposomal dry powder inhaler (LDPI) of azithromycin. This invention will significantly reduce the side effects that the drug causes to people who consume it currently in pill form.
Azithromycin is a widely prescribed drug for the treatment of respiratory tract infections. But as the drug enters the stomach and blood, it causes a number of side effects. There has always been a demand for a formulation that can help the drug reach its target organ — the organ where the bacteria that is causing respiratory infection resides — without causing side effects.
The team developed the new formulation by encapsulating azithromycin within liposomes (used as a carrier), converting it into a dry powder by freeze-drying and filling it in capsules. Patients can easily take drug doses through dry powder inhalers. The liposomal dry powder was evaluated using various in-vitro and animal studies. The in-vivo studies done on rats showed that the liposomes are retained in the lungs for a prolonged period of up to 12 hours with lesser presence in blood.
“These liposomes slowly released the loaded azithromycin into the lungs and thus avoided the exposure of the drug to stomach or blood. This helps in building local drug concentrations required for maximizing effectiveness and minimizing side effects.
Novel coronavirus affects male fertility levels: Study
City gynaecologists and fertility experts have found that the novel coronavirus has affected the fertility levels, particularly in men, as a majority of those infected hailed from the reproductive age.
As the body temperature is directly linked to the production of sperm, those suffering from Covid-19 with high fever, are at risk of infertility, though temporary. Fertility experts said fever has an impact on the parameters of sperm, including its motility and count. The worst-hit during the lockdown were the infertile couples as they could not have access to assisted reproductive techniques (ART). Even after relaxation in the lockdown, the access to the ART is limited.
The result of the study was published in the recent issue of ‘The Journal of Reproductive Health and Medicine’.
Russia detects first case of H5N8 avian flu in humans
Russia said Saturday that its scientists had detected the world's first case of transmission of the H5N8 strain of avian flu from birds to humans and had alerted the World Health Organization.
scientists at the Vektor laboratory had isolated the strain's genetic material from seven workers at a poultry farm in southern Russia, where an outbreak was recorded among the birds in December.
The workers did not suffer any serious health consequences, she added. They are believed to have caught the virus from poultry on the farm.
Information about the world's first case of transmission of the avian flu (H5N8) to humans has already been sent to the World Health Organization.
There are different subtypes of avian influenza viruses.
While the highly contagious strain H5N8 is lethal for birds, it had never before been reported to have spread to humans.
The discovery of these mutations when the virus has not still acquired an ability to transmit from human to human gives us all, the entire world, time to prepare for possible mutations and react in an adequate and timely fashion.
People can get infected with avian and swine influenza viruses, such as bird flu subtypes A(H5N1) and A(H7N9) and swine flu subtypes such as A(H1N1).
According to the WHO, people usually get infected through direct contact with animals or contaminated environments, and there is no sustained transmission among humans.
H5N1 in people can cause severe illness and has a 60 percent mortality rate.
Hedge plant effective at filtering automobile air pollutants
Researchers have found that the Cotoneaster franchetii (also known as Franchet's cotoneaster) hedge plant is effective at filtering automobile air pollutants. In their paper published in the journal Environments, they described experiments that involved testing different types of plants to find out which were best at filtering air pollution next to roadways.
The work is part of a 10-year ongoing research effort meant to better understand which plants might be the most useful in urban settings. They have been testing bushes, trees and shrubs that are commonly planted in urban to see which are the most effective against flooding and air pollution. Over that time span, they have tested a wide variety of hedges to see how well they can soak up air pollution generated by cars and trucks and have found that those with dense canopies and rough and hairy leaves, such as cotoneaster, are the most effective.
The team found that cotoneaster was 20% more effective at pulling pollutants out of the air on busy street sections than any other hedge that they studied. They acknowledge that they found little difference between hedges when testing on streets that did not have much traffic. They suggest this indicates that using different kinds of plants in different areas would make sense, both for home owners and city or town planners. They found that over the course of one week, a single 1-meter-long cotoneaster hedge was able to clean auto pollutants over the course of a 500-mile drive.
Because of its unique abilities, the researchers suggest that homeowners who have property abutting busy street sections plant cotoneaster to reduce the amount of pollution they are inhaling into their lungs every day. City planners could do likewise to reduce overall pollution levels in cities.
Tijana Blanuša et al. Evaluating the Effectiveness of Urban Hedges as Air Pollution Barriers: Importance of Sampling Method, Species Characteristics and Site Location, Environments (2020). DOI: 10.3390/environments7100081
Imagine abrupt shifts of the tropical monsoons, reductions in Northern Hemisphere rainfall, and strengthening of North Atlantic storm tracks within decades. These are some of the impacts that climate scientists expect if the Atlantic Meridional Overturning Circulation (AMOC), which redistributes heat from equatorial regions to the Northern Hemisphere, suddenly tips into a dormant state as a result of global warming. The consequences would drastically alter conditions for agriculture, biodiversity, and the economy in large parts of the World.
There are millions of unplugged oil wells in the United States, which pose a serious threat to the environment. Using drones, researchers from Binghamton University, State University of New York have developed a new method to locate these hard-to-locate and dangerous wells.
Every year, billions of tons of valuable soil are lost worldwide through erosion, much of it deposited in bodies of water that fill with sand or silt as a result. Soil losses measured in Germany range from 1.4 to 3.2 tons per hectare per year; in extreme weather, the figure can be as high as fifty tons. Geoscientists at the University of Tübingen have now shown how biological soil crusts provide a protective layer against erosion. Natural "carpets" of bacteria, mosses, lichens, fungi and other organisms bind soil particles into coherent layers, or crusts.
It has long been known that several chemicals used in plastic toys in different parts of the world can be harmful to human health. However, it is difficult for parents to figure out how to avoid plastic toys containing chemicals that may cause possible health risks to their children.
Critics claim environmental regulations hurt productivity and profits, but the reality is more nuanced, according to an analysis of environmental policies in China by a pair of Cornell economists.
If you thought you could head indoors to be safe from the air pollution that plagues your area or city, new research shows that elevated air pollution events claw their way into indoor spaces.
Researchers found that the amount of air pollution that comes indoors depends on the type of outdoor pollution. Wildfires, fireworks and wintertime inversions all affect indoor air to different degrees.
During their experiments, researchers found that in general, the pollution levels inside were about 30% of what they were outside.
That's not surprising because during inversions, only around 20% of the air pollution is what's called primary pollution—the particulate matter that comes directly from combustion exhaust. The rest is secondary—formed as gases undergo chemical reactions under specific meteorological conditions and combine to form solid particulates. As soon as the air comes indoors, those meteorological conditions change.
That changes the chemical environment for these particles and they actually dissociate. That's what we're suspecting is happening when these particles come into the building and that's why we don't observe them.
But still the air is still safer inside than outside.
Daniel Mendoza et al, Long-term analysis of the relationships between indoor and outdoor fine particulate pollution: A case study using research grade sensors, Science of The Total Environment (2021). DOI: 10.1016/j.scitotenv.2021.145778
Ghost particle from shredded star reveals cosmic particle accelerator
From a black hole to the South Pole: Scientists identify first neutrino from a tidal disruption event
Tracing back a ghostly particle to a shredded star, scientists have uncovered a gigantic cosmic particle accelerator. The subatomic particle, called a neutrino, was hurled towards Earth after the doomed star came too close to the supermassive black hole at the centre of its home galaxy and was ripped apart by the black hole's colossal gravity. It is the first particle that can be traced back to such a 'tidal disruption event' (TDE) and provides evidence that these little understood cosmic catastrophes can be powerful natural particle accelerators.
The observations also demonstrate the power of exploring the cosmos via a combination of different 'messengers' such as photons (the particles of light) and neutrinos, also known as multi-messenger astronomy.
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The neutrino began its journey some 700 million years ago, around the time the first animals developed on Earth. That is the travel time the particle needed to get from the far-away, unnamed galaxy (catalogued as 2MASX J20570298+1412165) in the constellation Delphinus (The Dolphin) to Earth. Scientists estimate that the enormous black hole is as massive as 30 million suns. "The force of gravity gets stronger and stronger, the closer you get to something. That means the black hole's gravity pulls the star's near side more strongly than the star's far side, leading to a stretching effect. This difference is called a tidal force, and as the star gets closer, this stretching becomes more extreme. Eventually it rips the star apart, and then we call it a tidal disruption event. It's the same process that leads to ocean tides on Earth, but luckily for us the moon doesn't pull hard enough to shred the Earth.
About half of the star's debris was flung into space, while the other half settled on a swirling disc around the black hole. Before plunging into oblivion, the matter from the accretion disc gets hotter and hotter and shines brightly. This glow was first detected by the Zwicky Transient Facility (ZTF) on Mount Palomar in California on 9 April 2019.
Half a year later, on 1 October 2019 the IceCube neutrino detector at the South Pole registered an extremely energetic neutrino from the direction of the tidal disruption event. It smashed into the Antarctic ice with a remarkable energy of more than 100 teraelectronvolts. For comparison, that's at least ten times the maximum particle energy that can be achieved in the world's most powerful particle accelerator, the Large Hadron Collider at the European particle physics lab CERN near Geneva.The extremely lightweight neutrinos hardly interact with anything, able to pass unnoticed through not just walls but whole planets or stars, and are hence often referred to as ghost particles. So, even catching just one high-energy neutrino is already a remarkable observation. Analysis showed that this particular neutrino had only a one in 500 chance of being purely coincidental with the TDE. The detection prompted further observations of the event with many instruments across the electromagnetic spectrum, from radio waves to X-rays.
- A tidal disruption event coincident with a high-energy neutrino; Robert Stein, Sjoert van Velzen, Marek Kowalski, et al.;Nature Astronomy, 2021, DOI: 10.1038/s41550-020-01295-8
- A concordance scenario for the observed neutrino from a tidal discruption event; Walter Winter and Cecilia Lunardini;Nature Astronomy, 2021, DOI: 10.1038/s41550-021-01305-3
Simply speaking while infected can potentially spread COVID-19
COVID-19 can spread from asymptomatic but infected people through small aerosol droplets in their exhaled breath. Most studies of the flow of exhaled air have focused on coughing or sneezing, which can send aerosols flying long distances.
However, speaking while near one another is also risky since the virus can be ejected by merely talking.
InPhysics of Fluids, scientists in Japan use smoke andlaser lightto study the flow of expelled breath near and around two people conversing in various relative postures commonly found in theservice industry, such as in hair salons, medical exam rooms, orlong-term care facilities.
In this study, electronic cigarettes were used to produce artificial smoke consisting of droplets about one-tenth micron in diameter, similar to the size of a virus particle. The liquid used in these vaping devices, a mixture of glycerin andpropylene glycol, produces a cloud of tiny droplets that scatter light from a laser, allowing visualization of airflow patterns.
To study the effect of speech on exhalation, the word "onegaishimasu," a typical Japanese greeting in a business setting. The experiments revealed the exhaled air from an unmasked person who is speaking tends to move downward under the influence of gravity. If a customer or patient is lying below, they could be infected. When a mask is worn while standing or sitting, the vapor cloud tends to attach to that person's body, which is warmer than the surrounding air and flows upward along the body. If the technician is leaning over, however, the aerosol cloud tends to detach from that person's body and fall onto the client below.
The investigators also experimented with face shields and found it can prevent any aerosols that leak from around the technician's mask from traveling down to thecustomer.
"The face shield promoted the rise of the exhaled breath," said Ishii. "Hence, it is more effective to wear both a mask and a face shield when providing services to customers."
"Relationship between human exhalation diffusion and posture in face-to-face scenario with utterance" Physics of Fluids (2021). DOI: 10.1063/5.0038380
Researchers are turning kitchen waste into biofuels
When we eat, our bodies convert food into energy that fuels our lives. But what happens to the energy stored in the several billion pounds of food thrown away annually?
As part of advancing sustainable energy solutions, scientists are converting food waste into clean, renewable fuel that could power our planes, trains and automobiles. Researchers successfully converted food waste into an energy-dense biofuel that could help replace today's fossil fuels. Early results suggest food waste might deliver a trifecta of efficiency, economic and environmental benefits.
scientists pursuing this begin by blending the waste, often with the help of customized equipment known as the Muffin Monster that grinds up everything from bones and gristle to seeds, wrappers and packaging. The resulting mush is warmed so it can be continuously pumped into a reactor and converted into fuel.
The researchers are testing different types of food waste to see if they can achieve consistent outcomes. During experiments, they address numerous chemical and process engineering challenges as they arise. They fine-tune the heat exchange design, resolve pumping issues and develop continuous separation techniques.
More than 87,000 scientific papers on coronavirus since pandemic
Study finds "astonishing" growth even as partnerships shrink
Scientists from around the world have published more than 87,000 papers about coronavirus between the start of the COVID-19 pandemic and October 2020, a new analysis shows.
Even given the importance of the pandemic, researchers were surprised by the huge number of studies and other papers that scientists produced on the subject in such a short time.
Nearly all of the scientific community around the world turned its attention to this one issue.
Physicists Just Reached a New Speed Limit For Moving Quantum Information
This latest research answers a fundamental question – how fast can a quantum process be? It's a useful piece of information to know if you want to build a quantum computer or a quantum network, as it tells you some of the limitations inherent in the system.
A digital twin of our planet is to simulate the Earth system in future. It is intended to support policy-makers in taking appropriate measures to better prepare for extreme events. A new strategy paper by European scientists and ETH Zurich computer scientists shows how this can be achieved.
Asteroid dust found in crater closes case of dinosaur extinction
Researchers think they have closed the case of what killed the dinosaurs, definitively linking their extinction with an asteroid that slammed into Earth 66 million years ago by finding a key piece of evidence: asteroid dust inside the impact crater.
Death by asteroid rather than by a series of volcanic eruptions or some other global calamity has been the leading hypothesis since the 1980s, when scientists found asteroid dust in the geologic layer that marks the extinction of the dinosaurs. This discovery painted an apocalyptic picture of dust from the vaporized asteroid and rocks from impact circling the planet, blocking out the sun and bringing about mass death through a dark, sustained global winter—all before drifting back to Earth to form the layer enriched in asteroid material that's visible today.
Researchers collected nearly 3,000 feet of rock core from the crater buried under the seafloor. Research from this mission has helped fill in gaps about the impact, the aftermath and the recovery of life.
The telltale sign of asteroid dust is the element iridium—which is rare in the Earth's crust, but present at elevated levels in certain types of asteroids. An iridium spike in the geologic layer found all over the world is how the asteroid hypothesis was born. In the new study, researchers found a similar spike in a section of rock pulled from the crater. In the crater, the sediment layer deposited in the days to years after the strike is so thick that scientists were able to precisely date the dust to a mere two decades after impact.
New study suggests supermassive black holes could form from dark matter
A new theoretical study has proposed a novel mechanism for the creation of supermassive black holes from dark matter. The international team find that rather than the conventional formation scenarios involving 'normal' matter, supermassive black holes could instead form directly from dark matter in high density regions in the centers of galaxies. The result has key implications for cosmology in the early Universe, and is published in Monthly Notices of the Royal Astronomical Society.
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Exactly howsupermassive black holesinitially formed is one of the biggest problems in the study of galaxy evolution today. Supermassive black holes have been observed as early as 800 million years after the Big Bang, and how they could grow so quickly remains unexplained.
Standard formation models involve normal baryonic matter—the atoms and elements that that make up stars, planets, and all visible objects—collapsing under gravity to form black holes, which then grow over time. However the new work investigates the potential existence of stable galactic cores made ofdark matter, and surrounded by a diluteddark matter halo, finding that the centers of these structures could become so concentrated that they could also collapse into supermassive black holes once a critical threshold is reached.
According to the model this could have happened much more quickly than other proposed formation mechanisms, and would have allowed supermassive black holes in the early Universe to form before thegalaxiesthey inhabit, contrary to current understanding.
Carlos R. Argüelles, the researcher at Universidad Nacional de La Plata and ICRANet who led the investigation comments: "This new formation scenario may offer a natural explanation for how supermassiveblack holesformed in the early Universe, without requiring prior star formation or needing to invoke seedblack holeswith unrealistic accretion rates."
Another intriguing consequence of the new model is that the critical mass for collapse into a black hole might not be reached for smaller dark matter halos, for example those surrounding some dwarf galaxies. The authors suggest that this then might leave smaller dwarf galaxies with a central dark matter nucleus rather than the expected black hole. Such a dark matter core could still mimic the gravitational signatures of a conventional central black hole, whilst the dark matter outer halo could also explain the observed galaxy rotation curves.
Carlos R Argüelles et al, On the formation and stability of fermionic dark matter haloes in a cosmological framework, Monthly Notices of the Royal Astronomical Society (2020). DOI: 10.1093/mnras/staa3986
A research team has succeeded in creating a micrometer-sized space-time crystal consisting of magnons at room temperature. With the help of the scanning transmission X-ray microscope Maxymus at Bessy II at Helmholtz Zentrum Berlin, they were able to film the recurring periodic magnetization structure in a crystal.
Superstructures formed by 'walking' molecules could help create neurons for regenerative medicine
If surgeons could transplant healthy neurons into patients living with neurodegenerative diseases or brain and spinal cord injuries?! And imagine if they could grow these neurons in the laboratory from a patients own cells using a synthetic, highly bioactive material that is suitable for 3D printing. By discovering a new printable biomaterial that can mimic properties of brain tissue, Northwestern University researchers are now closer to developing a platform capable of treating these conditions using regenerative medicine. A key ingredient to the discovery is the ability to control the self-assembly processes of molecules within the material, enabling the researchers to modify the structure and functions of the systems from the nanoscale to the scale of visible features.
A research group has demonstrated that these superstructures can enhance neuron growth, an important finding that could have implications for cell transplantation strategies for neurodegenerative diseases such as Parkinson’s and Alzheimer’s disease, as well as spinal cord injury.
This is the first example where researchers have been able to take the phenomenon of molecular reshuffling we reported in 2018 and harness it for an application in regenerative medicine.
A Vaccination against the Pandemic of Misinformation
False beliefs, similar to those seen in Alzheimer’s patients, may result from a lack of science literacy
Low educational attainment is a risk factor for Alzheimer’s disease and other forms of dementia, suggesting that high educational attainment is associated with fostering neuroanatomical conditions that protect our brain from the pathophysiologic changes of Alzheimer’s disease. This remarkable scientific finding supports the idea that high quality education and science literacy physiologically and functionally strengthen the brain, protecting us from the threat of false beliefs during times of uncertainty and crisis.
As the frequency and size of wildfires continues to increase worldwide, new research from Carnegie Mellon University scientists shows how the chemical aging of the particles emitted by these fires can lead to more extensive cloud formation and intense storm development in the atmosphere. The research was published online today in the journal Science Advances.
Beyond Earth, the general scientific consensus is that the best place to search for evidence of extraterrestrial life is Mars. However, it is by no means the only place. Aside from the many extrasolar planets that have been designated as "potentially-habitable," there are plenty of other candidates right here in our solar system. These include the many icy satellites that are thought to have interior oceans that could harbor life.
The mechanism by which the plant hormone cytokinin controls cell division has been discovered—a breakthrough that significantly improves our understanding of how plants grow.
The list of diseases and conditions complicated by obesity is a long one; it includes heart disease, cancer, diabetes and impaired wound healing, as well as skin infections. It is not always clear, however, in what way this complication is caused. New research published last month in Science Translational Medicine, has uncovered the mechanisms that link obesity and skin infections, and identified a treatment option that will soon be tested in a Phase 2 clinical trial.
The work is focused on discovering links between disease and the epithelial microbiome—that is, the normal bacteria that live on our skin—and how the skin's defense system can be optimized to treat or prevent disease. In this study, the goal was to identify how obesity contributes to higher rates of atopic dermatitis.
During the studies it was found that when mice 're fed a high fat diet and became obese as result, skin adipocytes (or fat cells) become enlarged and lost the ability to fight against bacterial invasion during a skin infection. The findings revealed that an increased number of mature adipocytes (fat cells) increases TGFβ signaling, which in turn decreases the number dermal adipocyte progenitors that produce an antimicrobial peptide called cathelicidin. This absence leaves the epidermis vulnerable to infection from common culprits like Staphylococcus aureus. In lean subjects (both mice and human in this study), the skin microbiome was successful in preventing Staph infections, as the number of mature fat cells was insufficient to disrupt the normal dermal fat functions that keep such infections at bay.
Ling-juan Zhang et al. Diet-induced obesity promotes infection by impairment of the innate antimicrobial defense function of dermal adipocyte progenitors, Science Translational Medicine (2021). DOI: 10.1126/scitranslmed.abb5280
Forests' long-term capacity to store carbon is dropping in regions with extreme annual fires
Researchers have analyzed decades' worth of data on the impact of repeated fires on ecosystems across the world. Their results, published today in the journal Nature Ecology and Evolution, show that repeated fires are driving long-term changes to tree communities and reducing their population sizes.
Savannah ecosystems, and regions with extreme wet or dry seasons were found to be the most sensitive to changes in fire frequency. Trees in regions withmoderate climateare more resistant. Repeated fires also cause less damage to tree species with protective traits like thicker bark.
These effects only emerge over the course of several decades: the effect of a single fire is very different from repeated burning over time. The study found that after 50 years, regions with the most extreme annual fires had 72% lower wood area—a surrogate for biomass—with 63% fewer individual treesthan in regions that never burned. Such changes to the tree community can reduce the forest's long-term ability to store carbon, but may buffer the effect of future fires.
Pellegrini, A.F.A. et al: 'Decadal changes in fire frequencies shift tree communities and functional traits.' Nature Ecology & Evolution, February 2021. DOI: 10.1038/s41559-021-01401-7
More intense and frequent fires are reducing the size of tree communities in many regions of the world.
Slower-growing tree species are better at surviving fires, but these may capture less atmospheric carbon and reduce nutrient availability in the soil.
Not all regions are suitable for planting trees to tackle climate change; schemes must consider local wildfire frequency, vegetation cover and climate, and how these might change over time.
Nanobodies could help CRISPR turn genes on and off
The genetic tool CRISPR has been likened to molecular scissors for its ability to snip out and replace genetic code within DNA. But CRISPR has a capability that could make it useful beyond genetic repairs. CRISPR can precisely locate specific genes.
Scientists now attached CRISPR to nanobodies to help it perform specific actions when it reached the right spot on DNA. They used this combo technique to transform CRISPR from a gene-editing scissors into a nanoscale control agent that can toggle specific genes on and off, like a light switch, to start or stop the flow of some health-related protein inside a cell.
This could enable researchers to explore new therapeutic applications in the field of epigenetics—which is the study of how genes behave inside cells.
Mike V. Van et al, Nanobody-mediated control of gene expression and epigenetic memory, Nature Communications (2021). DOI: 10.1038/s41467-020-20757-1
Scientists achieve breakthrough in culturing corals and sea anemones cells
Researchers have perfected the recipe for keeping sea anemone and coral cells alive in a petri dish for up to 12 days. The new study has important applications to study everything from evolutionary biology to human health.
Cnidarians are emerging model organisms for cell and molecular biology research. Yet, successfully keeping their cells in a laboratory setting has proved challenging due to contamination from the many microorganisms that live within these marine organisms or because the whole tissue survive in a culture environment.
Researchers used two emerging model organisms in developmental and evolutionary biology—the starlet sea anemone (Nematostella vectensis) and cauliflower coral (Pocillopora damicornis)—to find more successful way to grow these cell cultures in a laboratory setting. They tested 175 cell cultures from the two organisms and found that their cells can survive for on average 12 days if they receive an antibiotic treatment before being cultured.
James D. Nowotny et al, Novel methods to establish whole-body primary cell cultures for the cnidarians Nematostella vectensis and Pocillopora damicornis, Scientific Reports (2021). DOI: 10.1038/s41598-021-83549-7
How reliable are existing studies on microplastics in table salt?
Just as environmentally conscious scientists predicted, our excessive use of plastics is coming back to bite us. Microplastics (MPs), plastic particles smaller than a few millimeters, can now be found everywhere, but more so in seawater. As expected, MPs are harmful to both environment and health, although their exact effects are unclear.
To get a better grasp of the extent of the MP problem, it is necessary to quantify how much we are exposed to them. Tablesalthas been shown to contain MPs, making it an ideal study target to gauge human exposure to MPs. Although many studies have measured the concentration of MPs in different edible salts, each research group used vastly different methodologies of quantification, causing much variability between the results, and calling into question their validity.
To address this problem, in a study published in theJournal of Hazardous Materials, scientists from Incheon National University, Korea, conducted a systematic review of all published papers on MPs intable saltand analyzed the differences between their methodologies and results in detail.
They found that the concentration of MPs in edible salt according to the literature varied quite a bit, and that measurement and sample-preparation procedures of each study were causing these differences. However, the largest differences were caused by the methods used to identify MPs, the minimum cut-off size and the criteria for the selection of particles.
When not corrected by different measured minimum MP cutoff sizes, MP content differed from 10 to 600 times among different MP identification methods, with greatest values originating from visual observation and followed by spectroscopy methods
Scientists also found a notable correlation between logarithmic mean abundances of MPs and minimum cut-off size used, regardless of the identification method.
Hee-Jee Lee et al, Variation and Uncertainty of Microplastics in Commercial Table Salts: Critical Review and Validation, Journal of Hazardous Materials (2020). DOI: 10.1016/j.jhazmat.2020.123743
Crops have advanced a formidable vary of methods to beat back hungry, leaf-chomping bugs. Properly-knowndefensesembrace foul-tasting toxins, sticky resins and sharp thorns, and now scientists have recognized one more instance: microscopic wrinkles that make leaves more durable to stroll on.
Wrinkles kind in lots of leaves’ cuticles—coatings that restrict water evaporation, mediate gasoline alternate, and shield the plant from pathogens. The brand new analysis, revealedinRoyal Society Open Science, finds that together with the cuticle’s inherently slippery floor, its tiny wrinkles additionally assist discourage bugs. The wrinkles most certainly grow to be extra pronounced because the leaf matures and its cuticle builds up, ultimately increasing and buckling.
Were it not for humans, woolly mammoths would have lived for 4,000 more years, simulation shows
An international team of researchers has used computer simulations to show that it was likely a combination of climate change and human hunting that led to the extinction of the woolly mammoth. They have written a paper describing their findings, available on the bioRxiv preprint server—in it, they suggest that were it not for human hunters, the mammoths would have lasted another 4,000 years.
the researchers created a simulation showing wooly mammoth populations from approximately 21,000 years ago, to 4,000 years ago—the time when the last of the mammoths died out. To recreate conditions the mammoths faced, the researchers added climate data as well as known human hunting data. They ran their simulation over 90,000 times with slight changes to the factors that might have led to their demise. The simulations showed that the most likely scenario involved climate change pushing the mammoths into smaller environments and hunters finishing them off. Interestingly, the researchers also found that if they removed human hunters from the simulations, the majority of the mammoths held on for another 4,000 years.
Damien A. Fordham et al. Humans hastened the range collapse and extinction of woolly mammoth, bioRxiv (2021). DOI: 10.1101/2021.02.17.431706
Doppler radar improves lives by peeking inside air masses to predict the weather. A Purdue University team is using similar technology to look inside living cells, introducing a method to detect pathogens and treat infections in ways that scientists never have before.
In a new study, the team used Doppler to sneak a peek inside cells and track their metabolic activity in real time, without having to wait for cultures to grow. Using this ability, the researchers can test microbes found in food, water, and other environments to see if they are pathogens, or help them identify the right medicine to treat antibiotic-resistant bacteria.
Researchers worked with immortalized cell lines—cells that will live forever unless you kill them. They exposed the cells to different known pathogens, in this case salmonella and E. coli. They then used the Doppler effect to spy out how the cells reacted. These living cells are called "sentinels," and observing their reactions is called a biodynamic assay.
This strategy is broadly applicable when scientists have isolated an unknown microbe and want to know if it is pathogenic—harmful to living tissues—or not. Such cells may show up in food supply, water sources or even in recently melted glaciers.
Another benefit is the ability to quickly and directly diagnose which bacteria respond to which antibiotics.
Honggu Choi et al, Doppler imaging detects bacterial infection of living tissue, Communications Biology (2021). DOI: 10.1038/s42003-020-01550-8
Study suggests habitat loss is leading to inbreeding of Indian tigers
While Indian tigers have the highest genetic variation compared to other subspecies of the feline across the world, their populations continue to be fragmented by loss of habitat, leading to inbreeding and potential loss of this diversity, says a new study.
Habitat loss from human activities leads to tigers being "hemmed into their own protected area. Now, they can only mate with the other tigers in their own population. Over time, this will result in inbreeding, they will end up mating with their relatives. This inbreeding might compromise their fitness and their ability to survive.
While genetic diversity across a population improves their chances of survival in the future, the study said population fragmentation of tigers can decrease this variation, and endanger them further.
In the study, the scientists sequenced whole genomes from 65 individual tigers from four subspecies of the feline, and conducted a variety of population genomic analyses that quantify genetic variability. They investigated the partitioning of genetic variation, possible impacts of inbreeding, and demographic history, and possible signatures of local adaptation.
While the total genomic variation in Indian tigers was higher than in other subspecies, the study found that several individual tigers in the country had low variation, suggesting possible inbreeding.
Dr. Krishna Kumari Challa
Excessive use of sanitisers could erase your fingerprints: Experts
Experts are reporting cases where sanitisers are “wiping off” fingerprints along with the Covid-19 virus. Experts blamed the nature of alcohol for the phenomenon.
A lady reported: If you value your fingerprints, don’t over-sanitise. Nehal Mistry, a bank professional, learned this the hard way when the office biometric attendance machine failed to recognise her fingerprints.
The Bopal resident used to sanitise her hands at least six-seven times a day. “Even my home security system could not read my fingerprints. I was already receiving treatment for a skin problem. So, my dermatologist asked me to reduce the use of alcohol-based sanitiser and shift to soap-based cleaning. She also prescribed a few ointments. It worked, and I got my fingerprints back.”
Experts from the city are reporting cases where sanitisers are “wiping off” fingerprints along with the Covid-19 virus. Experts blamed the nature of alcohol for the phenomenon. The condition is temporary, but it can happen to people using sanitisers excessively or not using moisturisers enough, they added.
Due to the use of sanitisers and other hand rubs, there is abrasion of the skin’s upper layer (epidermis). The fingerprints are formed due to the ridges in this layer. The abrasions change it and a clear image is not formed. Edema (swelling) and contact dermatitis also affect the fingerprint pattern.
The issue is however not very common, assure experts. The issue with fingerprints is reported more in those with an existing history of hyperhidrosis (excessive sweating). Frequent use of sanitisers coupled with other skin issues can increase peeling of epidermis.
https://health.economictimes.indiatimes.com/news/industry/excessive...
Feb 18, 2021
Dr. Krishna Kumari Challa
Feb 18, 2021
Dr. Krishna Kumari Challa
COVID vaccines and safety: what the research says
https://www.nature.com/articles/d41586-021-00290-x?utm_source=Natur...
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Feb 18, 2021
Dr. Krishna Kumari Challa
Origin of the Armageddon causing comet
Feb 18, 2021
Dr. Krishna Kumari Challa
Scientists entered people’s dreams and got them ‘talking’
Because Lucid dreamers can hear and answer questions while still asleep, scientists find.
Scientists have successfully "talked" to a sleeping person in real-time by invading their dreams, a new study shows. The researchers say it's like trying to communicate with an astronaut on another world.
Dreamers can follow instructions, solve simple math problems and answer yes-no questions without ever waking up, according to the results of four experiments described Thursday (Feb. 18) in the journal Current Biology.
The researchers communicated directly with sleeping participants by asking them questions and having them respond with eye or facial movements during lucid dreams — when people are at minimum aware that they are dreaming. (Some lucid dreamers can control what happens in their dreams.)
Studying dreams is difficult because people often forget or distort details after waking up. That's in part because the brain doesn't form many new memories while sleeping and has a limited capacity to accurately store information after the dream has ended, according to the study.
To overcome this limitation, the researchers attempted to communicate with people while they were still dreaming. Because the study participants were having lucid dreams, that meant they could make a conscious effort to respond to cues coming in from the outside world, the researchers hypothesized.
Researchers placed electrodes on the participants' heads, to measure their brainwaves; next to their eyes, to track eye movements; and on their chin, to measure muscle activity. They used this data to determine when the participants entered the rapid eye movement (REM) stage of sleep, when lucid dreams are most likely to occur.
The researchers used several techniques across the experiments to communicate with dreamers during REM sleep, including asking them spoken questions and giving them encoded messages in flashing lights, beeping tones and physical taps, that the dreamers had been trained to decipher. If dreamers received and understood the question or message during a lucid dream, they then responded with a set of distinctive eye or facial movements that were interpreted by the electrodes.
"Such two-way communication — from outside to inside the dream and back out again — is something that may seem to belong to the domain of science fiction.
https://www.cell.com/current-biology/fulltext/S0960-9822(21)00059-2
https://www.livescience.com/real-time-communication-while-dreaming....
Feb 19, 2021
Dr. Krishna Kumari Challa
Metabolic mutations help bacteria resist drug treatment
Bacteria have many ways to evade the antibiotics that we use against them.
Most of the mutations known to confer resistance occur in the genes targeted by a particular antibiotic. Other resistance mutations allow bacteria to break down antibiotics or pump them out through their cell membranes.
Researchers have now identified another class of mutations that helps bacteria develop resistance. In a study of E. coli, they discovered that mutations to genes involved in metabolism can also help bacteria to evade the toxic effects of several different antibiotics. The findings shed light on a fundamental facet of how antibiotics work, and suggest potential new avenues for developing drugs that could enhance the effectiveness of existing antibiotics.
This study gives us insights into how we can boost the effectiveness of existing antibiotics because it emphasizes that downstream metabolism plays an important role. Specifically, the work indicates that the killing efficacy of an antibiotic can be enhanced if one can elevate the metabolic response of the treated pathogen. By turning down their metabolism after drug treatment, bacteria can prevent the buildup of harmful byproducts.
The findings raise the possibility that forcing bacteria into a heightened metabolic state could increase the effectiveness of existing antibiotics, the researchers say.
A.J. Lopatkin el al., "Clinically relevant mutations in core metabolic genes confer antibiotic resistance," Science (2021). science.sciencemag.org/cgi/doi … 1126/science.aba0862
"The genetic underground of antibiotic resistance," Science (2021). science.sciencemag.org/cgi/doi … 1126/science.abf7922
https://phys.org/news/2021-02-metabolic-mutations-bacteria-resist-d...
Feb 19, 2021
Dr. Krishna Kumari Challa
Scientists identify over 140,000 virus species in the human gut
Viruses are the most numerous biological entities on the planet. Now researchers have identified over 140,000 viral species living in the human gut, more than half of which have never been seen before.
The paper, published today (18 February 2021) in Cell, contains an analysis of over 28,000 gut microbiome samples collected in different parts of the world. The number and diversity of the viruses the researchers found was surprisingly high, and the data opens up new research avenues for understanding how viruses living in the gut affect human health.
The human gut is an incredibly biodiverse environment. In addition to bacteria, hundreds of thousands of viruses called bacteriophages, which can infect bacteria, also live there.
It is known that imbalances in our gut microbiome can contribute to diseases and complex conditions such as Inflammatory Bowel Disease, allergies and obesity. But relatively little is known about the role our gut bacteria, and the bacteriophages that infect them, play in human health and disease.
Using a DNA-sequencing method called metagenomics, researchers at the Wellcome Sanger Institute and EMBL's European Bioinformatics Institute (EMBL-EBI) explored and catalogued the biodiversity of the viral species found in 28,060 public human gut metagenomes and 2,898 bacterial isolate genomes cultured from the human gut.
The analysis identified over 140,000 viral species living in the human gut, more than half of which have never been seen before.
Camarillo-Guerrero, L.F., et al. (2021). Massive expansion of human gut bacteriophage diversity. Cell. DOI: doi.org/10.1016/j.cell.2021.01.029
https://phys.org/news/2021-02-scientists-virus-species-human-gut.ht...
Feb 19, 2021
Dr. Krishna Kumari Challa
Physics of tumours: Cancer cells become fluidised and squeeze through tissue
Researchers have achieved a breakthrough in research into how cancer cells spread. They demonstrated for the first time how cells deform in order to move in dense tumor tissues and squeeze past neighboring cells. The researchers found that motile cells work together to fluidise tumour tissue.
These first observations of a phase transition in human tumours change our basic concepts of tumour progression and could improve cancer diagnosis and therapy.
the research showed that human tumours contain solid and fluid cell clusters, which would be a breakthrough in scientists' understanding of tumour mechanics.
Steffen Grosser et al, Cell and Nucleus Shape as an Indicator of Tissue Fluidity in Carcinoma, Physical Review X (2021). DOI: 10.1103/PhysRevX.11.011033
https://phys.org/news/2021-02-physics-tumours-cancer-cells-fluidise...
Feb 19, 2021
Dr. Krishna Kumari Challa
Using plasma technology to feed the world
Using state-of-the-art plasma technology to make cheap fertilizer for small farmers may sound like magic, but it has now become reality. Researchers have built a small plasma-powered plant that produces nitrogen-based liquid fertilizer only using sun, water and air. The plant is easy to set up, sustainable and very efficient.
https://www.tue.nl/en/news/news-overview/01-01-1970-using-plasma-te...
https://phys.org/news/2021-02-plasma-technology-world.html?utm_sour...
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AI may mistake chess discussions as racist talk
"The Queen's Gambit," the recent TV mini-series about a chess master, may have stirred increased interest in chess, but a word to the wise: social media talk about game-piece colors could lead to misunderstandings, at least for hate-speech detection software.
Feb 19, 2021
Dr. Krishna Kumari Challa
The dogs trained to spot cancer
Feb 19, 2021
Dr. Krishna Kumari Challa
Earth’s magnetic field broke down 42,000 years ago and caused massive sudden climate change
Ancient trees show turning point in Earth history 42,000yr ago
Feb 19, 2021
Dr. Krishna Kumari Challa
Researchers observe stationary Hawking radiation in an analog black hole
Black holes are regions in space where gravity is very strong—so strong that nothing that enters them can escape, including light. Theoretical predictions suggest that there is a radius surrounding black holes known as the event horizon. Once something passes the event horizon, it can no longer escape a black hole, as gravity becomes stronger as it approaches its center.
Theoretical physicist Stephen Hawking predicted that while nothing can escape from within them, black holes spontaneously emit a limited amount of light, which is known as Hawking radiation. According to his predictions, this radiation is spontaneous (i.e., it arises from nothing) and stationary (i.e., its intensity does not change much over time).
Researchers at Technion- Israel Institute of Technology have recently carried out a study aimed at testing Hawking's theoretical predictions. More specifically, they examined whether the equivalent of Hawking radiation in an "artificial black hole" created in a laboratory setting was stationary.
If you go inside the event horizon there's no way to get out, even for light. Hawking radiation starts just outside the event horizon, where light can barely escape. That is really weird because there's nothing there; it's empty space. Yet this radiation starts from nothing, comes out, and goes towards Earth.
The Hawking radiation emitted by this analog black hole is made of sound waves, rather than light waves. The rubidium atoms flow faster than the speed of sound, so sound waves cannot reach the event horizon and escape from the black hole. Outside of the event horizon, however, the gas flows slowly, so sound waves can move freely.
According to Hawking's predictions, the radiation emitted by black holes is spontaneous. In one of their previous studies, Researchers were able to confirm this prediction in their artificial black hole. In their new study, they set out to investigate whether the radiation emitted by their black hole is also stationary (i.e., if it remains constant over time).
A black hole is supposed to radiate like a black body, which is essentially a warm object that emits a constant infrared radiation (i.e., black body radiation). Hawking suggested that black holes are just like regular stars, which radiate a certain type of radiation all the time, constantly. That's what they wanted to confirm in our study, and they did.
Observation of stationary spontaneous Hawking radiation and the time evolution of an analog black hole. Nature Physics(2021). DOI: 10.1038/s41567-020-01076-0
https://phys.org/news/2021-02-stationary-hawking-analog-black-hole....
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Feb 20, 2021
Dr. Krishna Kumari Challa
Spina bifida can be caused by uninherited genetic mutations
Genetic mutations which occur naturally during the earliest stages of an embryo's development can cause the severe birth defect spina bifida, finds a new experimental study in mice.
The research explains for the first time how a 'mosaic mutation' - a mutation which is not inherited from either parent (either via sperm or egg cell) but occurs randomly during cell divisions in the developing embryo—causes spina bifida.
Scientists
found that when a mutation in the gene Vangl2 (which contains information needed to create spinal cord tissue) was present in 16% of developing spinal cord cells of mouse embryos, this was sufficient to produce spina bifida.
Researchers say the findings add to scientists' understanding of how and why mosaic mutations can affect and disrupt cell function, including those of neighbouring cells, helping cause birth defects.
For parents, the findings may help reduce the burden felt by those who believe their child inherited spina bifida from them via genes, and believe future children could also inherit the condition. This is often discussed during genetic counselling.
Cell non-autonomy amplifies disruption of neurulation by mosaic Vangl2 deletion in mice, Nature Communications (2021). DOI: 10.1038/s41467-021-21372-4
https://medicalxpress.com/news/2021-02-spina-bifida-uninherited-gen...
Feb 20, 2021
Dr. Krishna Kumari Challa
People who don't suffer in cold have a genetic mutation to tolerate cold better
A new research has identified a specific genetic mutation that makes a fifth of us more resilient to cold conditions.
The genetic mutation in question stops the production of the protein α-actinin-3, which is important for skeletal muscle fibre: The protein is only found in fast-twitch (or white) fibres and not in slow-twitch (or red) fibres.
Based on the new study's results, people without α-actinin-3 have a higher proportion of slow-twitch fibres, and one of the consequences is that the body tends to conserve energy by building up muscle tone through contractions rather than shivering.
This suggests that people lacking α-actinin-3 are better at keeping warm and, energy-wise, at enduring a tougher climate. The loss of this protein gives a greater resilience to cold .
https://www.cell.com/ajhg/fulltext/S0002-9297(21)00013-6
https://www.sciencealert.com/1-in-5-of-us-have-a-genetic-mutation-t...
Feb 21, 2021
Dr. Krishna Kumari Challa
Common agricultural pesticide may be putting hummingbirds at risk: U of T study
Hummingbirds need an incredible amount of energy to flap their wings 50 times per second to maintain hovering flight. Their metabolism is so supercharged that if they were human-sized they would consume energy at a rate more than 10 times that of an Olympic marathon runner. But a new University of Toronto study has found that a common agricultural pesticide, which is related to nicotine in tobacco and might be slowing down the crucial physiological process that makes hummingbirds so unique upto 25% in the hours after exposure.
https://www.nature.com/articles/s41598-021-82470-3
https://www.utoronto.ca/news/common-agricultural-pesticide-may-be-p...
Feb 22, 2021
Dr. Krishna Kumari Challa
Lab-grown 'mini-bile ducts' used to repair human livers in regenerative medicine first
The research paves the way for cell therapies to treat liver disease – in other words, growing ‘mini-bile ducts’ in the lab as replacement parts that can be used to restore a patient’s own liver to health – or to repair damaged organ donor livers, so that they can still be used for transplantation.
Bile ducts act as the liver’s waste disposal system, and malfunctioning bile ducts are behind a third of adult and 70 per cent of children’s liver transplantations, with no alternative treatments. There is currently a shortage of liver donors: This means that only a limited number of patients can benefit from this therapy.
Approaches to increase organ availability or provide an alternative to whole organ transplantation are urgently needed. Cell-based therapies could provide an advantageous alternative. However, the development of these new therapies is often impaired and delayed by the lack of an appropriate model to test their safety and efficacy in humans before embarking in clinical trials.
Now, in a study published in Science, scientists have developed a new approach that takes advantage of a recent ‘perfusion system’ that can be used to maintain donated organs outside the body. Using this technology, they demonstrated for the first time that it is possible to transplant biliary cells grown in the lab known as cholangiocytes into damaged human livers to repair them. As proof-of-principle for their method, they repaired livers deemed unsuitable for transplantation due to bile duct damage. This approach could be applied to a diversity of organs and diseases to accelerate the clinical application of cell-based therapy.
https://science.sciencemag.org/content/371/6531/839
https://www.sanger.ac.uk/news_item/lab-grown-mini-bile-ducts-used-t...
https://researchnews.cc/news/5261/Lab-grown--mini-bile-ducts--used-...
Feb 22, 2021
Dr. Krishna Kumari Challa
Dancing DNA
Dancing DNA
This video allows us to see, for the first time, how small circles of DNA adopt dance-like movements inside a cell. Being able to observe DNA in such detail could help to accelerate the development of new gene therapies.
Feb 22, 2021
Dr. Krishna Kumari Challa
Electronics free, air-powered robot
Engineers have created a four-legged soft robot that doesn’t need any electronics to work. The robot only needs a constant source of pressurized air for all its functions, including its controls and locomotion systems.
Feb 22, 2021
Dr. Krishna Kumari Challa
No more popping pills, now just inhale your antibiotics!
You may not have to pop up azithromycin pills in the future. Instead, you will be able to simply inhale this most common antibiotic drug widely prescribed to treat respiratory tract infections of the nose, throat and lungs.
You may not have to pop up azithromycin pills in the future. Instead, you will be able to simply inhale this most common antibiotic drug widely prescribed to treat respiratory tract infections of the nose, throat and lungs.
Researchers of M S University’s Faculty of Pharmacy have received a patent for their invention of a liposomal dry powder inhaler (LDPI) of azithromycin. This invention will significantly reduce the side effects that the drug causes to people who consume it currently in pill form.
Azithromycin is a widely prescribed drug for the treatment of respiratory tract infections. But as the drug enters the stomach and blood, it causes a number of side effects. There has always been a demand for a formulation that can help the drug reach its target organ — the organ where the bacteria that is causing respiratory infection resides — without causing side effects.
The team developed the new formulation by encapsulating azithromycin within liposomes (used as a carrier), converting it into a dry powder by freeze-drying and filling it in capsules. Patients can easily take drug doses through dry powder inhalers.
The liposomal dry powder was evaluated using various in-vitro and animal studies. The in-vivo studies done on rats showed that the liposomes are retained in the lungs for a prolonged period of up to 12 hours with lesser presence in blood.
“These liposomes slowly released the loaded azithromycin into the lungs and thus avoided the exposure of the drug to stomach or blood. This helps in building local drug concentrations required for maximizing effectiveness and minimizing side effects.
https://health.economictimes.indiatimes.com/news/industry/no-more-p...
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Feb 22, 2021
Dr. Krishna Kumari Challa
Novel coronavirus affects male fertility levels: Study
City gynaecologists and fertility experts have found that the novel coronavirus has affected the fertility levels, particularly in men, as a majority of those infected hailed from the reproductive age.
As the body temperature is directly linked to the production of sperm, those suffering from Covid-19 with high fever, are at risk of infertility, though temporary. Fertility experts said fever has an impact on the parameters of sperm, including its motility and count. The worst-hit during the lockdown were the infertile couples as they could not have access to assisted reproductive techniques (ART). Even after relaxation in the lockdown, the access to the ART is limited.
The result of the study was published in the recent issue of ‘The Journal of Reproductive Health and Medicine’.
https://health.economictimes.indiatimes.com/news/industry/novel-cor...
Feb 22, 2021
Dr. Krishna Kumari Challa
Russia detects first case of H5N8 avian flu in humans
Russia said Saturday that its scientists had detected the world's first case of transmission of the H5N8 strain of avian flu from birds to humans and had alerted the World Health Organization.
scientists at the Vektor laboratory had isolated the strain's genetic material from seven workers at a poultry farm in southern Russia, where an outbreak was recorded among the birds in December.
The workers did not suffer any serious health consequences, she added. They are believed to have caught the virus from poultry on the farm.
Information about the world's first case of transmission of the avian flu (H5N8) to humans has already been sent to the World Health Organization.
There are different subtypes of avian influenza viruses.
While the highly contagious strain H5N8 is lethal for birds, it had never before been reported to have spread to humans.
The discovery of these mutations when the virus has not still acquired an ability to transmit from human to human gives us all, the entire world, time to prepare for possible mutations and react in an adequate and timely fashion.
People can get infected with avian and swine influenza viruses, such as bird flu subtypes A(H5N1) and A(H7N9) and swine flu subtypes such as A(H1N1).
According to the WHO, people usually get infected through direct contact with animals or contaminated environments, and there is no sustained transmission among humans.
H5N1 in people can cause severe illness and has a 60 percent mortality rate.
source: The Lancet
https://medicalxpress.com/news/2021-02-russia-case-h5n8-avian-flu.h...
Feb 23, 2021
Dr. Krishna Kumari Challa
Hedge plant effective at filtering automobile air pollutants
Researchers have found that the Cotoneaster franchetii (also known as Franchet's cotoneaster) hedge plant is effective at filtering automobile air pollutants. In their paper published in the journal Environments, they described experiments that involved testing different types of plants to find out which were best at filtering air pollution next to roadways.
Tijana Blanuša et al. Evaluating the Effectiveness of Urban Hedges as Air Pollution Barriers: Importance of Sampling Method, Species Characteristics and Site Location, Environments (2020). DOI: 10.3390/environments7100081
https://phys.org/news/2021-02-hedge-effective-filtering-automobile-...
Feb 23, 2021
Dr. Krishna Kumari Challa
Unfortunate timing and rate of change may be enough to tip a climat...
Imagine abrupt shifts of the tropical monsoons, reductions in Northern Hemisphere rainfall, and strengthening of North Atlantic storm tracks within decades. These are some of the impacts that climate scientists expect if the Atlantic Meridional Overturning Circulation (AMOC), which redistributes heat from equatorial regions to the Northern Hemisphere, suddenly tips into a dormant state as a result of global warming. The consequences would drastically alter conditions for agriculture, biodiversity, and the economy in large parts of the World.
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Drones used to locate dangerous, unplugged oil wells
There are millions of unplugged oil wells in the United States, which pose a serious threat to the environment. Using drones, researchers from Binghamton University, State University of New York have developed a new method to locate these hard-to-locate and dangerous wells.
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Carpets of moss help stop erosion
Every year, billions of tons of valuable soil are lost worldwide through erosion, much of it deposited in bodies of water that fill with sand or silt as a result. Soil losses measured in Germany range from 1.4 to 3.2 tons per hectare per year; in extreme weather, the figure can be as high as fifty tons. Geoscientists at the University of Tübingen have now shown how biological soil crusts provide a protective layer against erosion. Natural "carpets" of bacteria, mosses, lichens, fungi and other organisms bind soil particles into coherent layers, or crusts.
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Potentially harmful chemicals found in plastic toys
It has long been known that several chemicals used in plastic toys in different parts of the world can be harmful to human health. However, it is difficult for parents to figure out how to avoid plastic toys containing chemicals that may cause possible health risks to their children.
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Environmental policies not always bad for business, study finds
Critics claim environmental regulations hurt productivity and profits, but the reality is more nuanced, according to an analysis of environmental policies in China by a pair of Cornell economists.
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Feb 23, 2021
Dr. Krishna Kumari Challa
How outdoor pollution affects indoor air quality
If you thought you could head indoors to be safe from the air pollution that plagues your area or city, new research shows that elevated air pollution events claw their way into indoor spaces.
Researchers found that the amount of air pollution that comes indoors depends on the type of outdoor pollution. Wildfires, fireworks and wintertime inversions all affect indoor air to different degrees.
During their experiments, researchers found that in general, the pollution levels inside were about 30% of what they were outside.
That's not surprising because during inversions, only around 20% of the air pollution is what's called primary pollution—the particulate matter that comes directly from combustion exhaust. The rest is secondary—formed as gases undergo chemical reactions under specific meteorological conditions and combine to form solid particulates. As soon as the air comes indoors, those meteorological conditions change.
That changes the chemical environment for these particles and they actually dissociate. That's what we're suspecting is happening when these particles come into the building and that's why we don't observe them.
But still the air is still safer inside than outside.
Daniel Mendoza et al, Long-term analysis of the relationships between indoor and outdoor fine particulate pollution: A case study using research grade sensors, Science of The Total Environment (2021). DOI: 10.1016/j.scitotenv.2021.145778
https://phys.org/news/2021-02-outdoor-pollution-affects-indoor-air....
Feb 23, 2021
Dr. Krishna Kumari Challa
Ghost particle from shredded star reveals cosmic particle accelerator
From a black hole to the South Pole: Scientists identify first neutrino from a tidal disruption event
Tracing back a ghostly particle to a shredded star, scientists have uncovered a gigantic cosmic particle accelerator. The subatomic particle, called a neutrino, was hurled towards Earth after the doomed star came too close to the supermassive black hole at the centre of its home galaxy and was ripped apart by the black hole's colossal gravity. It is the first particle that can be traced back to such a 'tidal disruption event' (TDE) and provides evidence that these little understood cosmic catastrophes can be powerful natural particle accelerators.
The observations also demonstrate the power of exploring the cosmos via a combination of different 'messengers' such as photons (the particles of light) and neutrinos, also known as multi-messenger astronomy.
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The neutrino began its journey some 700 million years ago, around the time the first animals developed on Earth. That is the travel time the particle needed to get from the far-away, unnamed galaxy (catalogued as 2MASX J20570298+1412165) in the constellation Delphinus (The Dolphin) to Earth. Scientists estimate that the enormous black hole is as massive as 30 million suns. "The force of gravity gets stronger and stronger, the closer you get to something. That means the black hole's gravity pulls the star's near side more strongly than the star's far side, leading to a stretching effect. This difference is called a tidal force, and as the star gets closer, this stretching becomes more extreme. Eventually it rips the star apart, and then we call it a tidal disruption event. It's the same process that leads to ocean tides on Earth, but luckily for us the moon doesn't pull hard enough to shred the Earth.
About half of the star's debris was flung into space, while the other half settled on a swirling disc around the black hole. Before plunging into oblivion, the matter from the accretion disc gets hotter and hotter and shines brightly. This glow was first detected by the Zwicky Transient Facility (ZTF) on Mount Palomar in California on 9 April 2019.
Half a year later, on 1 October 2019 the IceCube neutrino detector at the South Pole registered an extremely energetic neutrino from the direction of the tidal disruption event. It smashed into the Antarctic ice with a remarkable energy of more than 100 teraelectronvolts. For comparison, that's at least ten times the maximum particle energy that can be achieved in the world's most powerful particle accelerator, the Large Hadron Collider at the European particle physics lab CERN near Geneva.The extremely lightweight neutrinos hardly interact with anything, able to pass unnoticed through not just walls but whole planets or stars, and are hence often referred to as ghost particles. So, even catching just one high-energy neutrino is already a remarkable observation. Analysis showed that this particular neutrino had only a one in 500 chance of being purely coincidental with the TDE. The detection prompted further observations of the event with many instruments across the electromagnetic spectrum, from radio waves to X-rays.
- A tidal disruption event coincident with a high-energy neutrino; Robert Stein, Sjoert van Velzen, Marek Kowalski, et al.; Nature Astronomy, 2021, DOI: 10.1038/s41550-020-01295-8
- A concordance scenario for the observed neutrino from a tidal discruption event; Walter Winter and Cecilia Lunardini; Nature Astronomy, 2021, DOI: 10.1038/s41550-021-01305-3
https://www.eurekalert.org/pub_releases/2021-02/ded-gpf021821.php
Feb 23, 2021
Dr. Krishna Kumari Challa
Using Light To Revolutionize Medical Imaging
Feb 23, 2021
Dr. Krishna Kumari Challa
Simply speaking while infected can potentially spread COVID-19
COVID-19 can spread from asymptomatic but infected people through small aerosol droplets in their exhaled breath. Most studies of the flow of exhaled air have focused on coughing or sneezing, which can send aerosols flying long distances.
However, speaking while near one another is also risky since the virus can be ejected by merely talking.
In Physics of Fluids, scientists in Japan use smoke and laser light to study the flow of expelled breath near and around two people conversing in various relative postures commonly found in the service industry, such as in hair salons, medical exam rooms, or long-term care facilities.
In this study, electronic cigarettes were used to produce artificial smoke consisting of droplets about one-tenth micron in diameter, similar to the size of a virus particle. The liquid used in these vaping devices, a mixture of glycerin and propylene glycol, produces a cloud of tiny droplets that scatter light from a laser, allowing visualization of airflow patterns.
To study the effect of speech on exhalation, the word "onegaishimasu," a typical Japanese greeting in a business setting. The experiments revealed the exhaled air from an unmasked person who is speaking tends to move downward under the influence of gravity. If a customer or patient is lying below, they could be infected. When a mask is worn while standing or sitting, the vapor cloud tends to attach to that person's body, which is warmer than the surrounding air and flows upward along the body. If the technician is leaning over, however, the aerosol cloud tends to detach from that person's body and fall onto the client below.
The investigators also experimented with face shields and found it can prevent any aerosols that leak from around the technician's mask from traveling down to the customer.
"The face shield promoted the rise of the exhaled breath," said Ishii. "Hence, it is more effective to wear both a mask and a face shield when providing services to customers."
"Relationship between human exhalation diffusion and posture in face-to-face scenario with utterance" Physics of Fluids (2021). DOI: 10.1063/5.0038380
https://phys.org/news/2021-02-simply-infected-potentially-covid-.ht...
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Feb 24, 2021
Dr. Krishna Kumari Challa
Researchers are turning kitchen waste into biofuels
When we eat, our bodies convert food into energy that fuels our lives. But what happens to the energy stored in the several billion pounds of food thrown away annually?
As part of advancing sustainable energy solutions, scientists are converting food waste into clean, renewable fuel that could power our planes, trains and automobiles. Researchers successfully converted food waste into an energy-dense biofuel that could help replace today's fossil fuels. Early results suggest food waste might deliver a trifecta of efficiency, economic and environmental benefits.
scientists pursuing this begin by blending the waste, often with the help of customized equipment known as the Muffin Monster that grinds up everything from bones and gristle to seeds, wrappers and packaging. The resulting mush is warmed so it can be continuously pumped into a reactor and converted into fuel.
The researchers are testing different types of food waste to see if they can achieve consistent outcomes. During experiments, they address numerous chemical and process engineering challenges as they arise. They fine-tune the heat exchange design, resolve pumping issues and develop continuous separation techniques.
https://phys.org/news/2021-02-kitchen-biofuels.html?utm_source=nwle...
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Feb 24, 2021
Dr. Krishna Kumari Challa
Can we regenerate damaged organs in the lab?
Scientists are trying to do just that!
Feb 24, 2021
Dr. Krishna Kumari Challa
More than 87,000 scientific papers on coronavirus since pandemic
Study finds "astonishing" growth even as partnerships shrink
Scientists from around the world have published more than 87,000 papers about coronavirus between the start of the COVID-19 pandemic and October 2020, a new analysis shows.
Even given the importance of the pandemic, researchers were surprised by the huge number of studies and other papers that scientists produced on the subject in such a short time.
Nearly all of the scientific community around the world turned its attention to this one issue.
https://www.eurekalert.org/pub_releases/2021-02/osu-mt8022221.php
Feb 24, 2021
Dr. Krishna Kumari Challa
Physicists Just Reached a New Speed Limit For Moving Quantum Information
This latest research answers a fundamental question – how fast can a quantum process be? It's a useful piece of information to know if you want to build a quantum computer or a quantum network, as it tells you some of the limitations inherent in the system.
https://journals.aps.org/prx/abstract/10.1103/PhysRevX.11.011035
https://www.sciencealert.com/a-new-quantum-speed-limit-discovery-sh...
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Scientists begin building highly accurate digital twin of our planet
A digital twin of our planet is to simulate the Earth system in future. It is intended to support policy-makers in taking appropriate measures to better prepare for extreme events. A new strategy paper by European scientists and ETH Zurich computer scientists shows how this can be achieved.
Feb 24, 2021
Dr. Krishna Kumari Challa
How to improve your life using science
https://www.sciencefocus.com/science/improve-your-life-with-science...
Feb 24, 2021
Dr. Krishna Kumari Challa
Asteroid dust found in crater closes case of dinosaur extinction
Researchers think they have closed the case of what killed the dinosaurs, definitively linking their extinction with an asteroid that slammed into Earth 66 million years ago by finding a key piece of evidence: asteroid dust inside the impact crater.
Death by asteroid rather than by a series of volcanic eruptions or some other global calamity has been the leading hypothesis since the 1980s, when scientists found asteroid dust in the geologic layer that marks the extinction of the dinosaurs. This discovery painted an apocalyptic picture of dust from the vaporized asteroid and rocks from impact circling the planet, blocking out the sun and bringing about mass death through a dark, sustained global winter—all before drifting back to Earth to form the layer enriched in asteroid material that's visible today.
Researchers collected nearly 3,000 feet of rock core from the crater buried under the seafloor. Research from this mission has helped fill in gaps about the impact, the aftermath and the recovery of life.
The telltale sign of asteroid dust is the element iridium—which is rare in the Earth's crust, but present at elevated levels in certain types of asteroids. An iridium spike in the geologic layer found all over the world is how the asteroid hypothesis was born. In the new study, researchers found a similar spike in a section of rock pulled from the crater. In the crater, the sediment layer deposited in the days to years after the strike is so thick that scientists were able to precisely date the dust to a mere two decades after impact.
"Globally distributed iridium layer preserved within the Chicxulub impact structure" Science Advances (2021). advances.sciencemag.org/lookup … .1126/sciadv.abe3647
https://phys.org/news/2021-02-asteroid-crater-case-dinosaur-extinct...
Feb 25, 2021
Dr. Krishna Kumari Challa
New study suggests supermassive black holes could form from dark matter
A new theoretical study has proposed a novel mechanism for the creation of supermassive black holes from dark matter. The international team find that rather than the conventional formation scenarios involving 'normal' matter, supermassive black holes could instead form directly from dark matter in high density regions in the centers of galaxies. The result has key implications for cosmology in the early Universe, and is published in Monthly Notices of the Royal Astronomical Society.
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Exactly how supermassive black holes initially formed is one of the biggest problems in the study of galaxy evolution today. Supermassive black holes have been observed as early as 800 million years after the Big Bang, and how they could grow so quickly remains unexplained.
Standard formation models involve normal baryonic matter—the atoms and elements that that make up stars, planets, and all visible objects—collapsing under gravity to form black holes, which then grow over time. However the new work investigates the potential existence of stable galactic cores made of dark matter, and surrounded by a diluted dark matter halo, finding that the centers of these structures could become so concentrated that they could also collapse into supermassive black holes once a critical threshold is reached.
According to the model this could have happened much more quickly than other proposed formation mechanisms, and would have allowed supermassive black holes in the early Universe to form before the galaxies they inhabit, contrary to current understanding.
Carlos R. Argüelles, the researcher at Universidad Nacional de La Plata and ICRANet who led the investigation comments: "This new formation scenario may offer a natural explanation for how supermassive black holes formed in the early Universe, without requiring prior star formation or needing to invoke seed black holes with unrealistic accretion rates."
Another intriguing consequence of the new model is that the critical mass for collapse into a black hole might not be reached for smaller dark matter halos, for example those surrounding some dwarf galaxies. The authors suggest that this then might leave smaller dwarf galaxies with a central dark matter nucleus rather than the expected black hole. Such a dark matter core could still mimic the gravitational signatures of a conventional central black hole, whilst the dark matter outer halo could also explain the observed galaxy rotation curves.
Carlos R Argüelles et al, On the formation and stability of fermionic dark matter haloes in a cosmological framework, Monthly Notices of the Royal Astronomical Society (2020). DOI: 10.1093/mnras/staa3986
https://phys.org/news/2021-02-supermassive-black-holes-dark.html?ut...
Feb 25, 2021
Dr. Krishna Kumari Challa
World's first video of a space-time crystal
A research team has succeeded in creating a micrometer-sized space-time crystal consisting of magnons at room temperature. With the help of the scanning transmission X-ray microscope Maxymus at Bessy II at Helmholtz Zentrum Berlin, they were able to film the recurring periodic magnetization structure in a crystal.
Feb 25, 2021
Dr. Krishna Kumari Challa
Superstructures formed by 'walking' molecules could help create neu...
Superstructures formed by 'walking' molecules could help create neurons for regenerative medicine
If surgeons could transplant healthy neurons into patients living with neurodegenerative diseases or brain and spinal cord injuries?! And imagine if they could grow these neurons in the laboratory from a patients own cells using a synthetic, highly bioactive material that is suitable for 3D printing. By discovering a new printable biomaterial that can mimic properties of brain tissue, Northwestern University researchers are now closer to developing a platform capable of treating these conditions using regenerative medicine. A key ingredient to the discovery is the ability to control the self-assembly processes of molecules within the material, enabling the researchers to modify the structure and functions of the systems from the nanoscale to the scale of visible features.
A research group has demonstrated that these superstructures can enhance neuron growth, an important finding that could have implications for cell transplantation strategies for neurodegenerative diseases such as Parkinson’s and Alzheimer’s disease, as well as spinal cord injury.
This is the first example where researchers have been able to take the phenomenon of molecular reshuffling we reported in 2018 and harness it for an application in regenerative medicine.
https://onlinelibrary.wiley.com/doi/10.1002/advs.202004042
https://onlinelibrary.wiley.com/doi/full/10.1002/advs.202004042
Feb 25, 2021
Dr. Krishna Kumari Challa
A Vaccination against the Pandemic of Misinformation
False beliefs, similar to those seen in Alzheimer’s patients, may result from a lack of science literacy
Low educational attainment is a risk factor for Alzheimer’s disease and other forms of dementia, suggesting that high educational attainment is associated with fostering neuroanatomical conditions that protect our brain from the pathophysiologic changes of Alzheimer’s disease. This remarkable scientific finding supports the idea that high quality education and science literacy physiologically and functionally strengthen the brain, protecting us from the threat of false beliefs during times of uncertainty and crisis.
Feb 25, 2021
Dr. Krishna Kumari Challa
Could comedy offer a way to communicate science more effectively?
Conference to explore adapting science communication to new challenges
https://www.irishtimes.com/news/science/could-comedy-offer-a-way-to...
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How wildfires may have larger effects on cloud formation than previ...
As the frequency and size of wildfires continues to increase worldwide, new research from Carnegie Mellon University scientists shows how the chemical aging of the particles emitted by these fires can lead to more extensive cloud formation and intense storm development in the atmosphere. The research was published online today in the journal Science Advances.
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Titan's atmosphere recreated in an Earth laboratory
Beyond Earth, the general scientific consensus is that the best place to search for evidence of extraterrestrial life is Mars. However, it is by no means the only place. Aside from the many extrasolar planets that have been designated as "potentially-habitable," there are plenty of other candidates right here in our solar system. These include the many icy satellites that are thought to have interior oceans that could harbor life.
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How plant stem cells renew themselves—a cytokinin story
The mechanism by which the plant hormone cytokinin controls cell division has been discovered—a breakthrough that significantly improves our understanding of how plants grow.
Feb 26, 2021
Dr. Krishna Kumari Challa
How obesity affects skin infections
The list of diseases and conditions complicated by obesity is a long one; it includes heart disease, cancer, diabetes and impaired wound healing, as well as skin infections. It is not always clear, however, in what way this complication is caused. New research published last month in Science Translational Medicine, has uncovered the mechanisms that link obesity and skin infections, and identified a treatment option that will soon be tested in a Phase 2 clinical trial.
Ling-juan Zhang et al. Diet-induced obesity promotes infection by impairment of the innate antimicrobial defense function of dermal adipocyte progenitors, Science Translational Medicine (2021). DOI: 10.1126/scitranslmed.abb5280
https://medicalxpress.com/news/2021-02-obesity-infection-link-treat...
Feb 26, 2021
Dr. Krishna Kumari Challa
Forests' long-term capacity to store carbon is dropping in regions with extreme annual fires
Researchers have analyzed decades' worth of data on the impact of repeated fires on ecosystems across the world. Their results, published today in the journal Nature Ecology and Evolution, show that repeated fires are driving long-term changes to tree communities and reducing their population sizes.
Savannah ecosystems, and regions with extreme wet or dry seasons were found to be the most sensitive to changes in fire frequency. Trees in regions with moderate climate are more resistant. Repeated fires also cause less damage to tree species with protective traits like thicker bark.
These effects only emerge over the course of several decades: the effect of a single fire is very different from repeated burning over time. The study found that after 50 years, regions with the most extreme annual fires had 72% lower wood area—a surrogate for biomass—with 63% fewer individual trees than in regions that never burned. Such changes to the tree community can reduce the forest's long-term ability to store carbon, but may buffer the effect of future fires.
Pellegrini, A.F.A. et al: 'Decadal changes in fire frequencies shift tree communities and functional traits.' Nature Ecology & Evolution, February 2021. DOI: 10.1038/s41559-021-01401-7
https://phys.org/news/2021-02-forests-long-term-capacity-carbon-reg...
Feb 26, 2021
Dr. Krishna Kumari Challa
Nanobodies could help CRISPR turn genes on and off
The genetic tool CRISPR has been likened to molecular scissors for its ability to snip out and replace genetic code within DNA. But CRISPR has a capability that could make it useful beyond genetic repairs. CRISPR can precisely locate specific genes.
Scientists now attached CRISPR to nanobodies to help it perform specific actions when it reached the right spot on DNA. They used this combo technique to transform CRISPR from a gene-editing scissors into a nanoscale control agent that can toggle specific genes on and off, like a light switch, to start or stop the flow of some health-related protein inside a cell.
This could enable researchers to explore new therapeutic applications in the field of epigenetics—which is the study of how genes behave inside cells.
Mike V. Van et al, Nanobody-mediated control of gene expression and epigenetic memory, Nature Communications (2021). DOI: 10.1038/s41467-020-20757-1
https://phys.org/news/2021-02-nanobodies-crispr-genes.html?utm_sour...
Feb 26, 2021
Dr. Krishna Kumari Challa
Scientists achieve breakthrough in culturing corals and sea anemones cells
Researchers have perfected the recipe for keeping sea anemone and coral cells alive in a petri dish for up to 12 days. The new study has important applications to study everything from evolutionary biology to human health.
Cnidarians are emerging model organisms for cell and molecular biology research. Yet, successfully keeping their cells in a laboratory setting has proved challenging due to contamination from the many microorganisms that live within these marine organisms or because the whole tissue survive in a culture environment.
Researchers used two emerging model organisms in developmental and evolutionary biology—the starlet sea anemone (Nematostella vectensis) and cauliflower coral (Pocillopora damicornis)—to find more successful way to grow these cell cultures in a laboratory setting. They tested 175 cell cultures from the two organisms and found that their cells can survive for on average 12 days if they receive an antibiotic treatment before being cultured.
James D. Nowotny et al, Novel methods to establish whole-body primary cell cultures for the cnidarians Nematostella vectensis and Pocillopora damicornis, Scientific Reports (2021). DOI: 10.1038/s41598-021-83549-7
https://phys.org/news/2021-02-scientists-breakthrough-culturing-cor...
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Feb 26, 2021
Dr. Krishna Kumari Challa
How reliable are existing studies on microplastics in table salt?
Just as environmentally conscious scientists predicted, our excessive use of plastics is coming back to bite us. Microplastics (MPs), plastic particles smaller than a few millimeters, can now be found everywhere, but more so in seawater. As expected, MPs are harmful to both environment and health, although their exact effects are unclear.
To get a better grasp of the extent of the MP problem, it is necessary to quantify how much we are exposed to them. Table salt has been shown to contain MPs, making it an ideal study target to gauge human exposure to MPs. Although many studies have measured the concentration of MPs in different edible salts, each research group used vastly different methodologies of quantification, causing much variability between the results, and calling into question their validity.
To address this problem, in a study published in the Journal of Hazardous Materials, scientists from Incheon National University, Korea, conducted a systematic review of all published papers on MPs in table salt and analyzed the differences between their methodologies and results in detail.
They found that the concentration of MPs in edible salt according to the literature varied quite a bit, and that measurement and sample-preparation procedures of each study were causing these differences. However, the largest differences were caused by the methods used to identify MPs, the minimum cut-off size and the criteria for the selection of particles.
When not corrected by different measured minimum MP cutoff sizes, MP content differed from 10 to 600 times among different MP identification methods, with greatest values originating from visual observation and followed by spectroscopy methods
Scientists also found a notable correlation between logarithmic mean abundances of MPs and minimum cut-off size used, regardless of the identification method.
Hee-Jee Lee et al, Variation and Uncertainty of Microplastics in Commercial Table Salts: Critical Review and Validation, Journal of Hazardous Materials (2020). DOI: 10.1016/j.jhazmat.2020.123743
https://phys.org/news/2021-02-salt-reliable-microplastics-table.htm...
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Feb 26, 2021
Dr. Krishna Kumari Challa
Dancing Roots
Feb 26, 2021
Dr. Krishna Kumari Challa
Microscopic Wrinkles in Leaves Ward Off Bugs
Crops have advanced a formidable vary of methods to beat back hungry, leaf-chomping bugs. Properly-known defenses embrace foul-tasting toxins, sticky resins and sharp thorns, and now scientists have recognized one more instance: microscopic wrinkles that make leaves more durable to stroll on.
Wrinkles kind in lots of leaves’ cuticles—coatings that restrict water evaporation, mediate gasoline alternate, and shield the plant from pathogens. The brand new analysis, revealed in Royal Society Open Science, finds that together with the cuticle’s inherently slippery floor, its tiny wrinkles additionally assist discourage bugs. The wrinkles most certainly grow to be extra pronounced because the leaf matures and its cuticle builds up, ultimately increasing and buckling.
https://royalsocietypublishing.org/doi/10.1098/rsos.201319
Feb 26, 2021
Dr. Krishna Kumari Challa
Were it not for humans, woolly mammoths would have lived for 4,000 more years, simulation shows
An international team of researchers has used computer simulations to show that it was likely a combination of climate change and human hunting that led to the extinction of the woolly mammoth. They have written a paper describing their findings, available on the bioRxiv preprint server—in it, they suggest that were it not for human hunters, the mammoths would have lasted another 4,000 years.
the researchers created a simulation showing wooly mammoth populations from approximately 21,000 years ago, to 4,000 years ago—the time when the last of the mammoths died out. To recreate conditions the mammoths faced, the researchers added climate data as well as known human hunting data. They ran their simulation over 90,000 times with slight changes to the factors that might have led to their demise. The simulations showed that the most likely scenario involved climate change pushing the mammoths into smaller environments and hunters finishing them off. Interestingly, the researchers also found that if they removed human hunters from the simulations, the majority of the mammoths held on for another 4,000 years.
Damien A. Fordham et al. Humans hastened the range collapse and extinction of woolly mammoth, bioRxiv (2021). DOI: 10.1101/2021.02.17.431706
https://phys.org/news/2021-02-humans-woolly-mammoths-years-simulati...
Feb 27, 2021
Dr. Krishna Kumari Challa
Scientists use Doppler to peer inside cells
Doppler radar improves lives by peeking inside air masses to predict the weather. A Purdue University team is using similar technology to look inside living cells, introducing a method to detect pathogens and treat infections in ways that scientists never have before.
In a new study, the team used Doppler to sneak a peek inside cells and track their metabolic activity in real time, without having to wait for cultures to grow. Using this ability, the researchers can test microbes found in food, water, and other environments to see if they are pathogens, or help them identify the right medicine to treat antibiotic-resistant bacteria.
Researchers worked with immortalized cell lines—cells that will live forever unless you kill them. They exposed the cells to different known pathogens, in this case salmonella and E. coli. They then used the Doppler effect to spy out how the cells reacted. These living cells are called "sentinels," and observing their reactions is called a biodynamic assay.
This strategy is broadly applicable when scientists have isolated an unknown microbe and want to know if it is pathogenic—harmful to living tissues—or not. Such cells may show up in food supply, water sources or even in recently melted glaciers.
Another benefit is the ability to quickly and directly diagnose which bacteria respond to which antibiotics.
Honggu Choi et al, Doppler imaging detects bacterial infection of living tissue, Communications Biology (2021). DOI: 10.1038/s42003-020-01550-8
https://phys.org/news/2021-02-scientists-doppler-peer-cells.html?ut...
Feb 27, 2021
Dr. Krishna Kumari Challa
https://www.youtube.com/watch?v=mwr-wF_IMeU
https://www.youtube.com/watch?v=9nzkF0hmy04
https://www.youtube.com/watch?v=I1Bdp2tMFsY
Feb 27, 2021
Dr. Krishna Kumari Challa
Study suggests habitat loss is leading to inbreeding of Indian tigers
While Indian tigers have the highest genetic variation compared to other subspecies of the feline across the world, their populations continue to be fragmented by loss of habitat, leading to inbreeding and potential loss of this diversity, says a new study.
Habitat loss from human activities leads to tigers being "hemmed into their own protected area. Now, they can only mate with the other tigers in their own population. Over time, this will result in inbreeding, they will end up mating with their relatives. This inbreeding might compromise their fitness and their ability to survive.
While genetic diversity across a population improves their chances of survival in the future, the study said population fragmentation of tigers can decrease this variation, and endanger them further.
https://academic.oup.com/mbe/advance-article/doi/10.1093/molbev/msa...
In the study, the scientists sequenced whole genomes from 65 individual tigers from four subspecies of the feline, and conducted a variety of population genomic analyses that quantify genetic variability. They investigated the partitioning of genetic variation, possible impacts of inbreeding, and demographic history, and possible signatures of local adaptation.
While the total genomic variation in Indian tigers was higher than in other subspecies, the study found that several individual tigers in the country had low variation, suggesting possible inbreeding.
https://www.thehindu.com/sci-tech/energy-and-environment/study-sugg...
Feb 27, 2021
Dr. Krishna Kumari Challa
How an ancient virus spread the ability to remember
A protein in your brain behaves like a virus, infecting your cells with memories
Forming a protective shell, Arc moves from neuron to neuron
Feb 27, 2021