Researchers find a single-celled slime mold with no nervous system that remembers food locations
Having a memory of past events enables us to take smarter decisions about the future. Researchers now identified the basis for forming memories in the slime mold Physarum polycephalum—despite its lack of a nervous system.
The ability to store and recover information gives an organism a clear advantage when searching for food or avoiding harmful environments, and has been traditionally linked to organisms that have a nervous system. A new study challenges this view by uncovering the surprising abilities of a highly dynamic,single-celled organism to store and retrieve information about its environment.
The slime mold Physarum polycephalum has been puzzling researchers for many decades. Existing at the crossroads between the kingdoms of animals, plants and fungi, this unique organism provides insight into the early evolutionary history of eukaryotes. Its body is a giant single cell made up of interconnected tubes that form intricate networks. This single amoeba-like cell may stretch several centimeters or even meters, featuring as the largest cell on earth in the Guinness Book of World Records.
The striking abilities of the slime mold to solve complex problems such as finding the shortest path through a maze earned it the attribute "intelligent," intrigued the research community and kindled questions about decision making on the most basic levels of life. The decision-making ability of Physarum is especially fascinating given that its tubular network constantly undergoes fast reorganization—growing and disintegrating its tubes—while completely lacking an organizing center. The researchers discovered that the organism weaves memories of food encounters directly into the architecture of the network-like body and uses the stored information when making future decisions.
Researchers followed the migration and feeding process of the organism and observed a distinct imprint of a food source on the pattern of thicker and thinner tubes of the network long after feeding. Given P. polycephalum's highly dynamic network reorganization, the persistence of this imprint sparked the idea that the network architecture itself could serve as memory of the past.
The researchers combined microscopic observations of the adaption of the tubular network with theoretical modeling. An encounter with food triggers the release of a chemical that travels from the location where food was found throughout the organism and softens the tubes in the network, making the whole organism reorient its migration towards the food.
The gradual softening is where the existing imprints of previous foodsources come into play and where information is stored and retrieved. Past feeding events are embedded in the hierarchy of tube diameters, specifically in the arrangement of thick and thin tubes in the network. For the softening chemical that is now transported, the thick tubes in the network act as highways in traffic networks, enabling quick transport across the whole organism. Previous encounters imprinted in the network architecture weigh into the decision about the future direction of migration.
Mirna Kramar et al. Encoding memory in tube diameter hierarchy of living flow network, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2007815118
Caterpillar silences tomato's cry for help, scientists find
"Silencing the alarm."
Scientists found that a caterpillar called the tomato fruit worm not only chomps on tomatoes and their leaves, but also deposits enzyme-laden saliva on the plant, interfering with its ability to cry for help.
It has been shown time and time again that when under attack, plants can emit chemical distress signals, causing their peers to mount some sort of defense. A classic example is the smell of a freshly mown lawn, which prompts the release of protective compounds in nearby blades of grass that have yet to be cut.
In some cases, plant distress signals can even summon help from other species. That's what happens with the tomato. When caterpillars nibble on the plant's leaves, the leaf pores release volatile chemicals that are detected by a type of parasite: a wasp that lays eggs inside caterpillars.
So can the caterpillars strike back? In a series of experiments, researchers found that the answer was yes, illustrating a previously unknown strategy in nature's age-old contest between predator and prey.
The key is the enzyme in the caterpillar's saliva, which inhibits the opening of pores in tomato-plant leaves. That means the leaves are less able to release the distress signals, and presumably less able to attract wasps that could come to the rescue.
Po‐An Lin et al. Silencing the alarm: an insect salivary enzyme closes plant stomata and inhibits volatile release, New Phytologist (2021). DOI: 10.1111/nph.17214
Coronavirus transmission through the placenta: Baby infected with coronavirus in the womb
A pregnant woman with suspected COVID-19 was rushed by ambulance to Skåne University Hospital, in Malmo, Sweden, suffering from sudden severe abdominal pain. The doctors noticed that the unborn infant had an abnormally low heart rate, which can be a sign that the baby is not getting enough oxygen.
The doctors performed an emergency caesarean section and delivered the baby within minutes. Blood tests from the baby confirmed it had severely low oxygen, and throat swabs showed that both mother and baby were suffering from COVID.
Using throat swabs from the mother and the newborn, the genome of the virus was sequenced to confirm the possibility that the infant had been infected with COVID while still in the womb.
a few days later, new genetic sequencing showed that the baby’s virus population had changed and contained a mutated version of the virus along with the original virus strain from the mother. To the best of our knowledge, this is the first case of a genetic change of the coronavirus in the unique setting of mother-to-foetus transmission before birth.
Although it is common for viruses to mutate, this mutation (called A107G) happened just five days after the baby was delivered. The genetic changes may have been stimulated by the baby coming in contact with the external environment outside the mother’s womb. However, it was surprising how quickly this single mutation occurred.
The most important findings were the changes seen in the placenta. The placenta takes blood and nutrients to the foetus and takes away waste and is critical for the growth and wellbeing of the foetus. Half the tissue was damaged. There was widespread inflammation, and coronavirus protein was found on both the mother’s and foetus’s side of the placenta. Also found was coronavirus protein in all areas that were damaged by inflammation.
with thousands of pregnant women infected worldwide, mother-to-baby transmission in the womb seems to be a rare complication of COVID during pregnancy.
Scientists think that this is because of the placental barrier that protects the baby in the womb from most infections. Also, the vital receptor needed for coronavirus entry into cells, called an ACE-2 receptor, only exists inlow levels in the placenta.
In rare cases, coronavirus can damage the placenta – leading to a lack of oxygen in the unborn child – even if the mother has a mild case of COVID in late pregnancy.
we should rethink how we monitor pregnant women who have COVID, and they should be considered a more important risk group than we do today.
Huge, Global Study of Plastic Toys Finds Over 100 Substances That May Harm Children
The potential health risks of chemicals used in plastic toys have had scientists concerned for years, but new research reveals just how widespread the risk of harm to children remains.
In an international study, researchers assessed the chemical compositions of toys and estimated levels of human exposure to the substances, ultimately finding over 100"Chemicals of Concern"in plastic toy materials that could pose a non-negligible health risk to children.
Out of 419 chemicals found in hard, soft, and foam plastic materials used in children toys, researchers identified 126 substances that can potentially harm children's health either via canceror non-cancer effects, including 31 plasticisers, 18 flame retardants, and 8 fragrances.
According to the researchers, while laws in many countries regulate the use of certain potentially toxic chemicals in plastic toys, there is no consistent approach internationally, and current protections don't adequately prohibit the vast extent of potentially harmful substances that toys are made from
In addition, some toxic and banned additives are still found in plastic toys also on regulated markets, for example in case of recycling contaminated plastics, unawareness by producers, or absence of regulations in the producing country.
The Oldest Known Mummification 'Recipe' Has Been Unearthed, And It's Intense
In an exciting discovery, researchers have discovered an original 'how to' manual, hidden inside an ancient text, which explains the crucial steps to embalming and creating a mummy.
The guide to mummification has been found on a 3,500-year-old piece of papyrus called the Papyrus Louvre-Carlsberg manuscript, so called because half of it, primarily containing medical information.
Among the details that Schiødt has teased out of the document is a list of instructions for embalming the face of the deceased person, which was done with a piece of red linen coated in a special plant-based solution.
The solution included aromatic substances as well as binders for holding the mixture together, and the saturated cloth was intended to keep the face protected from insects and bacteria while also smelling sweet. This process hasn't been documented before, but does match up with some of the mummified remainsthat have been found.
This manuscript also lays out the full 70-day schedule for embalming, split into two halves: a 35-day drying period and a 35-day wrapping period, which were themselves divided into four-day intervals. Common treatments to the body included applying a mixture called natron, after the removal of the organs and the brain.
People Are Accidentally Poisoning Themselves Trying to Treat COVID With a Horse Drug
People are trying to treat and prevent COVID-19 by taking ivermectin, a medication commonly used to de-worm horses – and they are poisoning themselves in the process.
US regulators say there is not enough robust evidence or safety data to recommend ivermectin as a cure, treatment, or preventative medicine for COVID-19.
While the FLCCC has held press conferences saying studies show the drug could fight against the novelcoronavirus, public health agencies and many experts say the research is lacking.
Ivermectin can be tolerated in small doses but can poison an adult in large quantities
Structure and dynamics of key receptor in migraine pain determined, paving way for better treatment options
A research team determined the shape and kinetics of an important cell surface (membrane) receptor called calcitonin gene-related peptide (CGRP), which has long been implicated in migraine. The researchers determined the structure of the receptor alone and in combination with its natural target molecule (CGRP). This gives us a clear understanding of how the receptor works during its normal function in the body. The work has been published in the journal Science.
Future studies will expand the investigations towards potential drug targets.
Tracy M. Josephs et al. Structure and dynamics of the CGRP receptor in apo and peptide-bound forms, Science (2021). DOI: 10.1126/science.abf7258
Migraine is more than a simple headache; more than 3 million migraineurs—more than 60% of whom are women—have at least one attack per year. A smaller subset experience chronic migraine, defined by migraine pain that occurs 15 days or more per month, for three or months in a row. While sufferers experience many different symptoms of varying intensity—usually nausea, dizziness, sensitivity to light and sound, and intense pain on one or both sides of the head—the physiological process of migraine onset and pain is different from other types of headache, such as muscle tension or sinus pain. While migraine was long believed to be a neurovascular disorder that involved dilation of vessels in the skull, face and cerebral membrane, research has excluded vasodilation as a factor in this type of pain. More recent work has identified increased CGRP in the trigeminal se... that results in headache.
Animals fake death for long periods to escape predators
Many animals feign death to try to escape their predators, with some individuals in prey species remaining motionless, if in danger, for extended lengths of time.
Charles Darwin recorded a beetle that remained stationary for 23 minutes—however the University of Bristol has documented an individual antlion larvae pretending to be dead for an astonishing 61 minutes. Of equal importance, the amount of time that an individual remains motionless is not only long but unpredictable. This means that a predator will be unable to predict when a potentialpreyitem will move again, attract attention, and become a meal.
Predators are hungry and cannot wait indefinitely. Similarly, prey may be losing opportunities to get on with their lives if they remain motionless for too long. Thus, death-feigning might best be thought of as part of a deadly game of hide and seek in which prey might gain most by feigning death if alternative victims are readily available.
The study, published today in science journalBiology Letters, involved evaluating the benefits of death-feigning in terms of a predator visiting small populations of conspicuous prey. Researchers usedcomputer simulationsthat utilise the marginal value theorem, a classical model in optimization.
Imagine seeing the world in muted shades—gray sky, gray grass. Some people with color blindness see everything this way, though most can't see specific colors. Tinted glasses can help, but they can't be used to correct blurry vision. And dyed contact lenses currently in development for the condition are potentially harmful and unstable. Now, in ACS Nano, researchers report infusing contact lenses with gold nanoparticles to create a safer way to see colors.
Color blindness-correcting contact lenses
Imagine seeing the world in muted shades—gray sky, gray grass. Some people with color blindness see everything this way, though most can't see specific colors.
Now researchers report infusing contact lenses with gold nanoparticles to create a safer way to see colors.
Some daily activities, such as determining if a banana is ripe, selecting matching clothes or stopping at a red light, can be difficult for those with colour blindness. Most people with this genetic disorder have trouble discriminating red and green shades, and red-tinted glasses can make those colors more prominent and easier to see. However, these lenses are bulky and the lens material cannot be made to fix vision problems. Thus, researchers have shifted to the development of special tinted contact lenses. Although the prototype hot-pink dyed lenses improved red-green color perception in clinical trials, they leached dye, which led to concerns about their safety. Gold nanocomposites are nontoxic and have been used for centuries to produce "cranberry glass" because of the way they scatter light.
To make the contact lenses, the researchers evenly mixed gold nanoparticles into a hydrogel polymer, producing rose-tinted gels that filtered light within 520-580 nm, the wavelengths where red and green overlap. The most effective contact lenses were those with 40 nm-wide gold nano particles, because in tests, these particles did not clump or filter more color than necessary. In addition, these lenses had water-retention properties similar to those of commercial ones and were not toxic to cells growing in petri dishes in the lab. Finally, the researchers directly compared their new material to two commercially available pairs of tinted glasses, and their previously developed hot-pink dyed contact lens. The gold nanocomposite lenses were more selective in the wavelengths they blocked than the glasses. The new lenses matched the wavelength range of the dyed contact lenses, suggesting the gold nanocomposite ones would be suitable for people with red-green color issues without the potential safety concerns. The researchers say that the next step is to conduct clinical trials with human patients to assess comfort.
Ahmed E. Salih et al. Gold Nanocomposite Contact Lenses for Color Blindness Management, ACS Nano (2021). DOI: 10.1021/acsnano.0c09657
Fireworks are used in celebrations around the world, including Independence Day in the U.S., the Lantern Festival in China and the Diwali Festival in India. However, the popular pyrotechnic displays emit large amounts of pollutants into the atmosphere, sometimes causing severe air pollution. Now, researchers reporting in ACS' Environmental Science & Technology have estimated that, although so-called environmentally friendly fireworks emit 15-65% less particulate matter than traditional fireworks, they still significantly deteriorate air quality.
Environmentally friendly fire works aren’t really that friendly!
Fireworks are used in celebrations around the world. However, the popular pyrotechnic displays emit large amounts of pollutants into the atmosphere, sometimes causing severe air pollution. Now, researchers reporting in ACS' Environmental Science & Technology have estimated that, although so-called environmentally friendly fireworks emit 15-65% less particulate matter than traditional fireworks, they still significantly deteriorate air quality.
Fireworks displays can cause health problems, such as respiratory ailments, because they release high levels of air pollutants, including particulate matter (PM), sulfur dioxide, heavy metals and perchlorates. As a result, some cities have banned their use. But because the displays are an important aspect of many traditional celebrations, researchers and manufacturers have tried to develop more environmentally friendly pyrotechnics, including those with smokeless charges and sulfur-free propellants. Although research suggests that these fireworks emit less pollutants, their impact on air quality has not been evaluated.
Now researchers wanted to see how green these fire works are.
The researchers estimated emissions of PM2.5, which is PM with a diameter of 2.5 μm and smaller, from the 160,000 environmentally friendly fireworks set off during the display, as well as emissions from traditional fireworks. They used information on the wind direction, wind speed, temperature and chemical composition of the fireworks to simulate the size, trajectory and peak PM2.5 values for the smoke plume resulting from the event. Then, they compared their simulated values with actual data on PM2.5 concentrations measured at 75 monitoring stations throughout the city following the fireworks display.
In agreement with the team's predictions, the data showed that the fireworks smoke plume began as a narrow band that traveled northward before being fully dispersed, with peak PM2.5 levels similar to the predictions. The researchers used their validated simulation to estimate that the use of environmentally friendly fireworks produces a much smaller, shorter-lasting plume, with 15-65% of the PM2.5 emissions of a display using traditional fireworks. However, the peak concentration of PM2.5 still greatly exceeds WHO guidelines.
This led the researchers to conclude that the number of "green" fireworks used at one time should be restricted.
"Are Environmentally Friendly Fireworks Really "Green" for Air Quality? A Study from the 2019 National Day Fireworks Display in Shenzhen" Environmental Science & Technology (2021). pubs.acs.org/doi/abs/10.1021/acs.est.0c03521
Climate experts have revealed that rising temperatures will intensify future rainfall extremes at a much greater rate than average rainfall, with largest increases to short thunderstorms.
When the Eyjafjallajökull volcano in Iceland erupted in April 2010, air traffic was interrupted for six days and then disrupted until May. Until then, models from the nine Volcanic Ash Advisory Centres (VAACs) around the world, which aimed at predicting when the ash cloud interfered with aircraft routes, were based on the tracking of the clouds in the atmosphere.
The New York State Center for Clean Water Technology (CCWT) at Stony Brook University has made a series of critical discoveries regarding a new approach to protecting Long Island's drinking water, groundwater, and surface waters. Some of the discoveries involve the likely human carcinogen, 1,4-dioxane, which has been found at higher levels in Long Island drinking water than anywhere else in the U.S.
We all know it's wrong to toss your rubbish into the ocean or another natural place. But it might surprise you to learn some plastic waste ends up in the environment, even when we thought it was being recycled.
Think all your plastic is being recycled? New research shows it can end up in the ocean
Some plastic waste ends up in the environment, even when we thought it was being recycled. Plastic waste most commonly leaks into the environment at the country to which it's shipped. Plastics which are of low value to recyclers, such as lids and polystyrene foam containers, are most likely to end up polluting the environment.
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Plastic waste collected for recycling is often sold for reprocessing in Asia. There, the plastics are sorted, washed, chopped, melted and turned into flakes or pellets. These can be sold to manufacturers to create new products.
The global recycled plastics market is dominated by two major plastic types:
polyethylene terephthalate (PET), which in 2017 comprised55% of the recyclable plastics market. It's used in beverage bottles and takeaway food containers and features a "1" on the packaging
high-density polyethylene (HDPE), which comprises about 33% of the recyclable plastics market. HDPE is used to create pipes and packaging such as milk and shampoo bottles, and is identified by a "2."
The next two most commonly traded types of plastics, each with 4% of the market, are:
polypropylene or "5," used in containers for yoghurt and spreads
low-density polyethylene known as "4," used in clear plastic films on packaging.
The remaining plastic types comprise polyvinyl chloride (3), polystyrene (6), other mixed plastics (7), unmarked plastics and "composites." Composite plastic packaging is made from several materials not easily separated, such as long-life milk containers with layers of foil, plastic and paper.
This final group of plastics is not generally sought after as a raw material in manufacturing, so has little value to recyclers.
Coronavirus: what happens when a person is simultaneously infected with two variants?
Scientists in Brazilrecently reportedthat two people were simultaneously infected with two different variants of SARS-CoV-2, the virus that causes COVID-19. This co-infection seemed to have no effect on the severity of patients’ illness, and both recovered without needing to be hospitalised.
Although this is one of the few such cases recorded with SARS-CoV-2 – and the study is yet to be published in a scientific journal – scientists have observed infections with multiple strainswith other respiratory viruses, such as influenza. This has raised questions about how these viruses may interact in an infected person, and what it could mean for generating new variants.
The detection of multiple variants in a person could be the result of co-infection by the different variants, or the generation of mutations within the patient after the initial infection. One way to discriminate these two scenarios is by comparing the sequences of the variants circulating in the population with those in the patient. In the Brazilian study mentioned above, the variants identified corresponded to different lineages that had been previously detected in the population, implying co-infection by the two variants.
It is important to note that this requires the two viruses to infect thesamecell. Even if a person is infected with several variants, if they replicate in different parts of the body, they will not interact with each other. Indeed,this was seenin patients, where different quasi-species of coronaviruses were found in the upper and lower respiratory tracts, suggesting that viruses in these sites were not directly mixing with each other.
The evidence so far does not suggest that infection with more than one variant leads to more severe disease. And although possible, very few cases of co-infection have been reported. More than 90% of the infections in the UK currently are by B117 – the so-called Kent variant. With such a high prevalence of one variant in the population, co-infections are not likely to occur. Still, monitoring this landscape allows scientists to track the emergence of these new variants of concern and understand and respond to any changes in their transmission or vaccine efficacy.
Where do bodily tissues get their strength? New CU Boulder research provides important new clues to this long-standing mystery, identifying how specialized proteins called cadherins join forces to make cells stick and stay stuck together. The findings, publishing this week in the Proceedings of the National Academy of Sciences, could lead to more life-like artificial tissues and tumor busting drugs. Better understanding these proteins allows for the design of more effective engineered tissues that better mimic biological materials as well as cancer therapeutics that are more efficient and target-specific.
For example: If a cancer treatment could block a specific interaction of these cadherin proteins, it could potentially slow tumor growth by stopping or slowing the formation of new blood vessels in tumors.
Cadherin proteins are important in our bodies because they facilitate the binding and adhesion of cells in neural, cardiac, placental and skin tissues, among others, helping them maintain their function and shape.
These large, rod-like proteins in the cell membrane mediate information between the inside and outside of the cell. Where they stick out, they can bond with other cadherin proteins from the same cell, as well as those from other cells.
Like Velcro, the study found, the more pieces stick together, the stronger the bond and the longer it lasts. This amplified strength not only between proteins which exist on the same cell, but between proteins located on different cells—creating bonds 30 times stronger than the sum of their individual strengths. And once the bonding begins, these bonds become progressively stronger and stronger.
Researchers discover new way to halt excessive inflammation
Researchers have discovered a new way to 'put the brakes' on excessive inflammation by regulating a type of white blood cell that is critical for our immune system. The discovery has the potential to protect the body from unchecked damage caused by inflammatory diseases.
Excessive inflammation is a prominent feature of many diseases such as multiple sclerosis, arthritis and inflammatory bowel diseases.
Whenimmune cells(white blood cells) in our body called macrophages are exposed to potent infectious agents, powerful inflammatory proteins known as cytokines are produced to fight the invading infection. However, if these cytokine levels get out of control, significant tissue damage can occur.
The researchers have found that a protein called Arginase-2 works through the energy source of macrophagecells, known as mitochondria, to limit inflammation. Specifically they have shown for the first time that Arginase-2 is critical for decreasing a potent inflammatory cytokine called IL-1.
This discovery could allow researchers to develop new treatments that target the Arginase-2 protein and protect the body from unchecked damage caused by inflammatory diseases.
'Fungal ghosts' protect skin, fabric from toxins, radiation
The idea of creating selectively porous materials has captured the attention of chemists for decades. Now, new research from Northwestern University shows that fungi may have been doing exactly this for millions of years.
When scientists set out to synthesize melanin that would mimic that which was formed by certain fungi known to inhabit unusual, hostile environments including spaceships, dishwashers and even Chernobyl, they did not initially expect the materials would prove highly porous— a property that enables the material to store and capture molecules.
Many women complain that they 're not being considered or overlooked for awards and prizes including the Nobel prize (1) in science just because of their gender. I recently found an interesting thing. I got a national award for science communication. During the award giving ceremony, Indian science and Tech secretary told us an interesting story.
Department of Science and Technology, India, gives prizes for the best PhD write up to train and make the budding scientists better at science communication. This year, they removed the names before sending the articles for assessment. And magic, magic, magic, magic. All the prize winners are women! Not even a single man got it.
What did we learn from it? Patriarchal mindsets are definitely impeding womens' chances of winning awards and prizes in science! Once you change the situation where there is no way to learn for the judge whether the person who is being judged is male or female, there is a better chance for women to win!
Eyeless roundworms sense color Roundworms don't have eyes or the light-absorbing molecules required to see. Yet, new research shows they can somehow sense color. The study, published on March 5 in the journal Science, suggests worms use this ability to assess the risk of feasting on potentially dangerous bacteria that secrete blue toxins. The researchers pinpointed two genes that contribute to this spectral sensitivity and are conserved across many organisms, including humans. So a 1 mm tiny worm, Caenorhabditis elegans, with neither eyes nor the molecular machinery used by eyes to detect colors can identify and avoid a toxic bacterium based, in part, on its blue color! They can smell, taste, sense touch, react to temperature, and even escape or change their feeding patterns in response to bright, blue light.
Scientists read 300-year-old letters without opening them
The letters had been folded using a mysterious technique.
Unopened letters more than 300 years old that were folded using mysterious techniques have now been read for the first time without opening them, a new study finds.
For centuries, before mass-produced envelopes started proliferating in the 1830s, most letters across the globe were sent usingletterlocking, a method of folding letters to become their own envelopes. These intricate techniques also often served to help recipients detect if mail had been tampered with.
For example, during research in theVatican Secret Archives, conservator Jana Dambrogio at the MIT Libraries unearthed Renaissance letters with odd slits and sliced-off corners. She discovered these were signs these documents were originally locked with a slice of paper slid through a slit and closed with a wax seal. Such letters could not be opened without ripping the paper, which would reveal to intended recipients if someone else had read the letters first.
After studying 250,000 historical letters, Dambrogio and her colleagues devised the first system tocategorize letterlockingtechniques, a kind of periodic table based on how these strategies creased sheets. "Letterlocking is a 10,000-year-old technology -- as long as people have tried to build security into their correspondences, you've had letterlocking, from cuneiform tablets all the way to bitcoin paper wallets.
Until now, scientists could only read these "letterpackets" by cutting them open, often damaging the documents. Although such work naturally focused on the letter's contents, this came at the cost of research into letterlocking itself, about which much remains unknown. "These folding sequences, they're just like a sneeze -- they're ephemeral. The minute you open them, you lose evidence of them.
Now scientists have devised a way to both read letterlocked texts without opening them and reconstruct the complex folds, tucks and slits used to secure them.
The scientists investigated theBrienne Collection, a postmaster's trunk holding more than 3,000 undelivered letters, including 577 letterpackets that were never opened. The letters were sent from all over Europe to The Hague between 1680 and 1706, the era that saw the Salem witch trials unfold, Newton reveal his laws of motion and gravitation, and Louis XIV move his court to Versailles.
The researchers first analyzed four letterpackets with high-resolution X-ray scans to generate 3D models of the documents. Next, they used a new computational algorithm to identify and separate different layers of the folded letters and recognize text written on them. Finally, the algorithm virtually unfolded the letters, not only making the writing visible, but also recording the crease patterns so the researchers could re-create the letterlocking process step by step.
This new strategy helped the scientists read unopened letterlocked text for the first time.
Scientists discover why blood type may matter for COVID infection
A new study provides further evidence that people with certain blood types may be more likely to contract COVID-19.
Specifically, it found that the new coronavirus (SARS-CoV-2) is particularly attracted to the blood groupA antigen found on respiratory cells.
The researchers focused on a protein on the surface of the SARS-CoV-2 virus called the receptor binding domain (RBD), which is the part of the virus that attaches to the host cells. That makes it an important target for scientists trying to learn how the virus infects people.
In this laboratory study, the team assessed how the SARS-CoV-2 RBD interacted with respiratory and red blood cells in A, B and O blood types.
The results showed that the SARS-CoV-2 RBD had a strong preference for binding to blood group A found on respiratory cells, but had no preference for blood group Ared blood cells, or other blood groups found on respiratory or red cells.
The SARS-CoV-2 RBD's preference to recognize and attach to the blood type A antigen found in the lungs of people with blood type A may provide insight into the potential link between blood group A and COVID-19 infection, according to the authors of the study. It was published March 3 in the journalBlood Advances.
Brain cells called astrocytes derived from the induced pluripotent stem cells of patients with bipolar disorder offer suboptimal support for neuronal activity. In a paper in the journal Stem Cell Reports, researchers show that this malfunction can be traced to an inflammation-promoting molecule called interleukin-6 (IL-6), which is secreted by astrocytes. The results highlight the potential role of astrocyte-mediated inflammatory signaling in the psychiatric disease, although further investigation is needed.
Economic benefits of protecting nature now outweigh those of exploiting it, global data reveal
The economic benefits of conserving or restoring natural sites "outweigh" the profit potential of converting them for intensive human use, according to the largest-ever study comparing the value of protecting nature at particular locations with that of exploiting it.
A research team analysed dozens of sites—from Kenya to Fiji and China to the UK—across six continents. A previous breakthrough study in 2002 only had information for five sites.
For the latest study, scientists calculated the monetary worth of each site's "ecosystem services", such ascarbon storageand flood protection, as well as likely dividends from converting it for production of goods such as crops and timber.
The team initially concentrated on 24 sites and compared their "nature-focused" and "alternative" states by working out the annual net value of a range of goods and services for each site under each state, then projected the data over the next 50 years.
A major economic benefit of natural habitats comes from their regulation of the greenhouse gases driving climate change, including the sequestration of carbon.
In a new report now published on Science Advances, Elinor Zerah Harush and Yonatan Dubi in the departments of chemistry and nanoscale science and technology, at the Ben-Gurion University of the Negev, Israel, discussed a direct evaluation of the effects of quantum coherence on the efficiency of three natural photosynthetic complexes. The open quantum systems approach allowed the researchers to simultaneously identify the quantum-nature and efficiency under natural physiological conditions. These systems resided in a mixed quantum-classical regime, which they characterized using dephasing-assisted transport. The efficiency was minimal at best therefore the presence of quantum coherence did not play a substantial role in the process. The efficiency was also independent of any structural parameters, suggesting the role of evolution during structural design for other uses.
Researchers of the Toschi group of Eindhoven University of Technology think the water phase change problem with considering the water density anomaly is of great importance relating to common natural phenomena. Their research plan is firstly to understand the physics fundamentals, that is, the coupled problem of the stably and unstably stratified layers with considering the density anomaly.
At Dubai airport, travelers' eyes become their passports
Dubai's airport, the world's busiest for international travel, can already feel surreal, with its cavernous duty-free stores, artificial palm trees, gleaming terminals, water cascades and near-Arctic levels of air conditioning.
Now, the key east-west transit hub is rolling out another addition from the realm of science fiction—an iris-scanner that verifies one's identity and eliminates the need for any human interaction when entering or leaving the country.
That's because the airport debuted a new "smart tunnel" that uses biometric technology, instead of human checks, to allow some air travelers to complete passport control in just 15 seconds.
It's the latest artificial intelligence program the United Arab Emirates has launched amid the surging coronavirus pandemic, contact-less technology the government promotes as helping to stem the spread of the virus. But the efforts also have renewed questions aboutmass surveillancein the federation of seven sheikhdoms, which experts believe has among the highest per capita concentrations of surveillance cameras in the world.
Dubai's airport started offering the program to all passengers last month. On Sunday, travelers stepped up to an iris scanner after checking in, gave it a good look and breezed through passport control within seconds. Gone were the days of paper tickets or unwieldy phone apps.
In recent years, airports across the world have accelerated their use of timesaving facial recognition technology to move passengers to their flights. But Dubai's iris scan improves on the more commonplace automated gates seen elsewhere, authorities said, connecting the iris data to the country's facial recognition databases so the passenger needs no identifying documents or boarding pass.
Now, all the procedures have become 'smart,' around five to six seconds
Iris biometrics are considered more reliable than surveillance cameras that scan people's faces from a distance without their knowledge or consent.
Ways to spot if someone is trying to mislead you in science
It’s not a new thing for people to try to mislead you when it comes to science.
The challenge is to be able to identify when this may be happening. Sometimes it’s easy, as often even the most basic fact-checking and logic can be potent weapons against misinformation.
But often, it can be hard. People who are trying either to make you believe something that isn’t true, or to doubt something that is true, use a variety of strategies that can manipulate you very effectively.
These red flags can alert you ....
1.The ‘us versus them’ narrative: This is one of the most common tactics used to mislead. It taps into our intrinsic distrust of authority and paints those with evidence-based views as part of some other group that’s not be trusted.
2. ‘I’m not a scientist, but…’: People tend to use the phrase “I’m not a scientist, but…” as a sort of universal disclaimer which they feel allows them to say whatever they want, regardless of scientific accuracy.
3. Reference to ‘the science not being settled’
This is perhaps one of the most powerful strategies used to mislead.
There are of course times when the science is not settled, and when this is the case, scientists openly argue different points of view based on the evidence available.
4. Overly simplistic explanations
Oversimplifications and generalisations are where many conspiracy theories are born.
Science is often messy, complex and full of nuance. The truth can be much harder to explain, and can sometimes sound less plausible, than a simple but incorrect explanation.
We’re naturally drawn to simple explanations. And if they tap into our fears and exploit our cognitive biases — systematic errors we make when we interpret information — they can be extremely seductive.
5. Cherry-picking
People who use this approach treat scientific studies like individual chocolates in a gift box, where you can choose the ones you like and disregard the ones you don’t. Of course, this isn’t how science works.
It’s important to understand not all studies are equal; some provide much stronger evidence than others. You can’t just conveniently put all your faith in the studies that align with your views, and ignore those that don’t.
When scientists evaluate evidence, they go through a systematic process to assess the whole body of evidence. This is a crucial task that requires expertise.
The cherry-picking tactic can be hard to counter because unless you’re across all the evidence, you’re not likely to know whether the studies being presented have been deliberately curated to mislead you.
This is yet another reason to rely on the experts who understand the full breadth of the evidence and can interpret it sensibly.
Humidity in breath makes cotton masks more effective at slowing the spread of COVID-19
Researchers have come up with a better way to test which fabrics work best for masks that are meant to slow the spread of COVID-19. By testing those fabrics under conditions that mimic the humidity of a person's breath, the researchers have obtained measurements that more accurately reflect how the fabrics perform when worn by a living, breathing person.
The new measurements show that under humid conditions, the filtration efficiency—a measure of how well a material captures particles—increased by an average of 33% in cotton fabrics. Synthetic fabrics performed poorly relative to cotton, and their performance did not improve with humidity. The material from medical-procedure masks also did not improve with humidity, though it performed in roughly the same range as cottons.
The filtration efficiency of cotton fabrics increases in humid conditions because cotton is hydrophilic, meaning it likes water. By absorbing small amounts of the water in a person's breath, cotton fibers create a moist environment inside the fabric. As microscopic particles pass through, they absorb some of this moisture and grow larger, which makes them more likely to get trapped.
Most synthetic fabrics, on the other hand, are hydrophobic, meaning they dislike water. These fabrics do not absorb moisture, and their filtration efficiency does not change in humid conditions.
Christopher D. Zangmeister et al, Hydration of Hydrophilic Cloth Face Masks Enhances the Filtration of Nanoparticles, ACS Applied Nano Materials (2021). DOI: 10.1021/acsanm.0c03319
Researchers have demonstrated that a slimy, yet tough, type of biofilm that certain bacteria make for protection and to help them move around can also be used to separate water and oil. The material may be useful for applications such as cleaning contaminated waters.
They reported the findings of an experiment in which they used a material produced by the bacteria Gluconacetobacter hansenii as a filter to separate water from an oil mixture.
The biofilm the bacteria make and release into their environment is made of cellulose, which is the same material that gives plants a sturdy structure in their cell walls. However, when bacteria make cellulose, it has a tightly packed, crystalline structure. It's one of the purest, if not the purest, forms of cellulose out there. The bacteria make the film to protect themselves.
The material was effective at removing water, and it 's sturdy. The oil doesn't want to go through the membrane; it has a repulsive effect to it. It's super fat-hating.
Researchers see a variety of potential applications for the material in situations where you need to recover water from an oily mixture—whether it be to clean water contaminated with a textile dye or for environmental remediation.
Zahra Ashrafi et al. Bacterial Superoleophobic Fibrous Matrices: A Naturally Occurring Liquid-Infused System for Oil–Water Separation, Langmuir (2021). DOI: 10.1021/acs.langmuir.0c02717
Autotomy, the voluntary shedding of a body part, is common to distantly-related animals such as arthropods, gastropods, asteroids, amphibians, and lizards. Autotomy is generally followed by regeneration of shed terminal body parts, such as appendages or tails. A a new type of extreme autotomy ‘s reported recently.
Two species of sea slug,Elysia marginataandElysia atroviridis, decapitate themselves — only to regrow a new body from the severed head. Researchers were astonished toobserve slugs in captivity cutting off their own headsafter their bodies became infected with parasites. Within 3 weeks, the heads regenerate a whole, parasite-free body, though the bodies never grow back new heads.
Scientists develop new magnetic nanomaterial for counterfeit money prevention
An international research team has developed a new iron-cobalt-nickel nanocomposite with tunable magnetic properties. The nanocomposite could be used to protect money and securities from counterfeiting.
The new iron-cobalt-nickel nanocomposite was obtained by chemical precipitation, followed by a reduction process.
The new composite was observed to possess high value of coercivity, which makes the technology applicable e.g. to magnetic rubbers and different magnetically coupled devices. Another potential application is protecting money and securities from counterfeiting.
Tien Hiep Nguyen et al, Impact of Iron on the Fe–Co–Ni Ternary Nanocomposites Structural and Magnetic Features Obtained via Chemical Precipitation Followed by Reduction Process for Various Magnetically Coupled Devices Applications, Nanomaterials (2021). DOI: 10.3390/nano11020341
Bacteria know how to exploit quantum mechanics, study finds
Photosynthetic organisms harvest light from the sun to produce the energy they need to survive. A new paper published by University of Chicago researchers reveals their secret: exploiting quantum mechanics.
Before this study, the scientific community saw quantum signatures generated in biological systems and asked the question, were these results just a consequence of biology being built from molecules, or did they have a purpose?" said Greg Engel, Professor of Chemistry and senior author on the study. "This is the first time we are seeing biology actively exploiting quantum effects.
The scientists studied a type of microorganism called green sulfur bacteria. These bacteria need light to survive, but even small amounts of oxygen can damage their delicate photosynthetic equipment. So they must develop ways to minimize the damage when thebacteriumdoes encounter oxygen.
To study this process, researchers tracked the movement of energy through a photosynthetic protein under different conditions—with oxygen around, and without.
They found that the bacterium uses a quantum mechanical effect called vibronic mixing to move energy between two different pathways, depending on whether or not there's oxygen around. Vibronic mixing involves vibrational and electronic characteristics in molecules coupling to one another. In essence, the vibrations mix so completely with the electronic states that their identities become inseparable. This bacterium uses this phenomenon to guide energy where it needs it to go.
If there's no oxygen around and the bacterium is safe, the bacterium uses vibronic mixing by matching the energy difference between two electronic states in an assembly of molecules and proteins called the FMO complex, with the energy of the vibration of a bacteriochlorophyll molecule. This encourages the energy to flow through the 'normal' pathway toward the photosynthetic reaction center, which is packed full of chlorophyll.
But if there is oxygen around, the organism has evolved to steer the energy through a less direct path where it can be quenched. (Quenching energy is similar to putting a palm on a vibrating guitar string to dissipate energy.) This way, the bacterium loses some energy but saves the entire system.
Jacob S. Higgins et al, Photosynthesis tunes quantum-mechanical mixing of electronic and vibrational states to steer exciton energy transfer, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2018240118
Recent studies estimate that we use an astounding 129 billion face masks globally every month—that is 3 million a minute. Most of them are disposable face masks made from plastic microfibers.
With increasing reports on inappropriate disposal of masks, it is urgent to recognize this potential environmental threat and prevent it from becoming the next plastic problem.
Disposable masks are plastic products, that cannot be readily biodegraded but may fragment into smaller plastic particles, namely micro- and nanoplastics that widespread in ecosystems.
The enormous production of disposable masks is on a similar scale as plastic bottles, which is estimated to be 43 billion per month. However, different from plastic bottles, (of which app. 25 pct. is recycled), there is no official guidance on mask recycle, making it more likely to be disposed of as solid waste
If not disposed of for recycling, like other plastic wastes, disposable masks can end up in the environment, freshwater systems, and oceans, where weathering can generate a large number of micro-sized particles (smaller than 5 mm) during a relatively short period (weeks) and further fragment into nanoplastics (smaller than 1 micrometer).
"A newer and bigger concern is that the masks are directly made from microsized plastic fibers (thickness of ~1 to 10 micrometers). When breaking down in the environment, the mask may release more micro-sized plastics, easier and faster than bulk plastics like plastic bags.
How can you solve it?
Researchers recommend these solutions:
Set up mask-only trash cans for collection and disposal
consider standardization, guidelines, and strict implementation of waste management for mask wastes
replace disposable masks with reusableface maskslike cotton masks
consider development of biodegradable disposalmasks.
Elvis Genbo Xu et al, Preventing masks from becoming the next plastic problem, Frontiers of Environmental Science & Engineering (2021). DOI: 10.1007/s11783-021-1413-7
At first glance, the fabric looks like a pretty if not especially original scarf, with turquoise, blue and orange stripes in an open weave. But this fabric can communicate.
It's wearable, foldable and washable, but it's also a fully functioning display—capable of flashing messages or images, or even being used with a keyboard.
it could revolutionize communication and "help individuals with voice, speech or language difficulties to express themselves to others".
Over the past decades, physicists worldwide have been trying to gain a better understanding of non-equilibrium dynamics in quantum many-body systems. Some studies investigated what are known as quasiparticles, disturbances or entities in physical systems that exhibit behavior similar to that of particles.
Researchers at Aarhus University recently carried out a study investigating the non-equilibrium dynamics of a quantum impurity immersed in a bosonic environment. Their paper, published in Nature Physics, sheds light on the dynamical behavior of interacting many-body systems, while also improving the current understanding of how Bose polarons are formed.
Quasiparticles are extremely interesting, since they may consist of countless particles and their excitations.
The idea of quasiparticles was first introduced in the 1930s by physicist Lev Landau, who was trying to gain a better understanding of complex quantum systems. The experiments carried out now build on models created by Landau.
In their studies, the researchers prepared coherent superposition states of atoms in a Bose-Einstein condensate with a small impurity-state component using an interferometric technique. Subsequently, they monitored the evolution of these quantum superpositions and their transition into polaronic quasiparticles.
Remarkably, the researchers were able to observe the birth of a unique class of quasiparticles, called Bose polarons, for the very first time. While in the past several research groups detected signs of these quasiparticles in laboratory settings, so far observing their gradual formation over time proved highly challenging, mainly because the processes through which they are formed are exceedingly fast.
Foodborne fungus impairs intestinal wound healing in Crohn's disease
Eating is a dangerous business. Naturally occurring toxins in food and potentially harmful foodborne microbes can do a number on our (injure) intestines, leading to repeated minor injuries. In healthy people, such damage typically heals in a day or two. But in people with Crohn's disease, the wounds fester, causing abdominal pain, bleeding, diarrhea and other unpleasant symptoms.
Crohn's is a subtype of inflammatory bowel disease. As the name suggests, it is driven by chronic inflammation in the digestive tract and primarily treated with immunosuppressive medications. Crohn's patients endure repeated cycles of gastrointestinal symptom flare-up and remission. During a flare, their digestive tracts are dotted with inflamed, open sores that can persist for weeks or even months.
Researchers discovered that a fungus found in foods such as cheese and processed meats can infect sites of intestinal damage in mice and people with Crohn's and prevent healing. Moreover, treating infected mice with antifungal medicationeliminates the fungus and allows the woundsto heal.
The findings, published March 12 in the journalScience, suggest that antifungal drugs and dietary changes are potential new approaches to improving intestinal wound healing and reducing symptoms of Crohn's disease.
Rainbows are some of the most spectacular optical phenomena in the natural world
Hawai'i's location in the subtropical Pacific means the overall weather pattern is dominated bytrade winds, with frequent rain showers and clear skies between the showers.
Businger outlines four additional factors affecting the prevalence of rainbows throughout the islands.
"At night a warm sea surface heats the atmosphere from below, while radiation to space cools cloud tops, resulting in deeper rain showers in the morning that produce rainbows in time for breakfast," said Businger.
Another critical factor in producing frequent rainbows is Hawai'i's mountains, which cause trade wind flow to be pushed up, forming clouds and producing rainfall. Without mountains, Hawai'i would be a desert with a scant 17 inches annual rainfall.
A third factor conducive to rainbow sightings is daytime heating, which drives island-scale circulations. During periods of lighter winds, showers form over the ridge crests over Oahu and Kauai in the afternoon, resulting in prolific rainbows as the sun sets.
Due to the remoteness of the Hawaiian Islands, the air is exceptionally clean and free of pollution, continental dust, and pollen. This is the fourth factor that contributes to the numerous bright rainbows with the full spectrum of colors.
Steven Businger, The Secrets of the Best Rainbows on Earth, Bulletin of the American Meteorological Society (2020). DOI: 10.1175/BAMS-D-20-0101.1
One of the most classic algorithmic problems deals with calculating the shortest path between two points. A more complicated variant of the problem is when the route traverses a changing network—whether this be a road network or the internet. For 40 years, researchers have sought an algorithm that provides an optimal solution to this problem. Now, computer scientist Christian Wulff-Nilsen of the University of Copenhagen and two research colleagues have come up with a recipe.
When heading somewhere new, most of us leave it to computer algorithms to help us find the best route, whether by using a car's GPS, or public transport and map apps on their phone. Still, there are times when a proposed route doesn't quite align with reality. This is because road networks, public transportation networks and other networks aren't static. The best route can suddenly be the slowest, e.g. because a queue has formed due to roadworks or an accident.
People probably don't think about the complicated math behind routing suggestions in these types of situations. The software being used is trying to solve a variant for the classic algorithmic "shortest path" problem, the shortest path in a dynamic network. For 40 years, researchers have been working to find an algorithm that can optimally solve this mathematical conundrum. Now, Christian Wulff-Nilsen of the University of Copenhagen's Department of Computer Science has succeeded in cracking the nut along with two colleagues.
The researchers represent a network as a so-called dynamic graph. In this context, a graph is an abstract representation of a network consisting of edges, roads for example, and nodes, representing intersections, for example. When a graph is dynamic, it means that it can change over time. The new algorithm handles changes consisting of deleted edges—for example, if the equivalent of a stretch of a road suddenly becomes inaccessible due to road work.
Traditional algorithms assume that a graph is static, which is rarely true in the real world. When these kinds of algorithms are used in a dynamic network, they need to be rerun every time a small change occurs in the graph—which wastes time.
Aaron Bernstein, et al. Near-Optimal Decremental SSSP in Dense Weighted Digraphs. arXiv:2004.04496v2 [cs.DS] arxiv.org/abs/2004.04496
How to spot deepfakes? Look at light reflection in the eyes
Computer scientists have developed a tool that automatically identifies deepfake photos by analyzing light reflections in the eyes.
The tool proved 94% effective with portrait-like photos in experiments described in a paper accepted at the IEEE International Conference on Acoustics, Speech and Signal Processing to be held in June in Toronto, Canada.
The cornea is almost like a perfect semisphere and is very reflective. So, anything that is coming to the eye with a light emitting from those sources will have an image on the cornea. The two eyes should have very similar reflective patterns because they're seeing the same thing. It's something that we typically don't typically notice when we look at a face.
When we look at something, the image of what we see is reflected in our eyes. In a real photo or video, the reflections on the eyes would generally appear to be the same shape and color.
However, most images generated by artificial intelligence—including generative adversary network (GAN) images—fail to accurately or consistently do this, possibly due to many photos combined to generate the fake image.
Now the researchers tool exploits this shortcoming by spotting tiny deviations in reflected light in the eyes of deepfake images.
While promising, this new technique has limitations.
For one, you need a reflected source of light. Also, mismatchedlightreflections of the eyes can be fixed during editing of the image. Additionally, the technique looks only at the individual pixels reflected in the eyes—not the shape of the eye, the shapes within the eyes, or the nature of what's reflected in the eyes.
Finally, the technique compares the reflections within both eyes. If the subject is missing an eye, or the eye is not visible, the technique fails.
Using softened wood to create electricity in homes
A multi-institutional team of researchers has found that it is possible to use a type of fungus to soften wood to the point that it could be used to generate electricity. In their paper published in the journal Science Advances, the group describes their process and how they tested it.
As the world works its way toward cleaner energy-producing systems, scientists seek novel approaches to producingelectricity. One possibility is the use of piezoelectric devices that generate electricity by harnessing movement such as footsteps. In this new effort, the researchers have noted that much energy is wasted when people walk around. And while some have attempted to harness some of that energy with devices designed for shoes or legs, the researchers with this new effort wondered if it might be possible to add piezoelectrics to thefloorto make use of that energy.
In studying the kinds ofwoodthat are used to make floors, particularly in homes, the researchers noted that they do not have much give—a necessary component of anenergy-harvesting system. To solve that problem, they found that applying a type of white rot fungus to pieces of balsa wood for a few weeks sped up the decaying process in a useful way. It made the wood spongier, which translated to give. When stepping on the wood, the researchers could feel it depress. They also found that after the wood returned to its former shape when pressure was removed.
To test their idea, the researchers treated a wooden veneer with the fungus and then added a piezoelectric device, which sent the power it produced through a wire attached to an LED light. The wood was then placed on a floor where people could walk on it. Each time they did so, the light came on. The researchers note that the amount of electricity generated was just 0.85 volts but the system could very easily be scaled up to include all the flooring in a home, generating enough electricity, perhaps, to power certain devices.
Jianguo Sun et al. Enhanced mechanical energy conversion with selectively decayed wood, Science Advances (2021). DOI: 10.1126/sciadv.abd9138
How can some planets be hotter than stars? We’ve started to unravel the mystery
Data from the Kepler mission has shown that large, gaseous exoplanets can orbit very close to their star – rather than far away from it, as is the case in our Solar System, causing them to reach temperatures exceeding 1,000K (727°C). These have been dubbed “hot” or “ultra-hot” Jupiters.
But how can hot, gaseous planets form and exist so close to their star? What kind of extreme physical processes happen here? Answers to those questions have large implications in our understanding of exoplanets and solar system planets. In our recent study, published in The Astrophysical Journal Letters, we have added another piece to the puzzle of planet formation and evolution.
The hottest exoplanet known so far is Kelt-9 b, which was discovered in 2016. Kelt-9 b orbits a star that is twice as hot as our Sun, at a distance ten times closer than Mercury orbits our star. It is a large gaseous exoplanet, with a radius 1.8 times that of Jupiter and temperatures reaching 5,000K. For comparison, this is hotter than 80% of all the stars in the universe and a similar temperature to our Sun.
In essence, hot Jupiters are a window into extreme physical and chemical processes. They offer an incredible opportunity to study physics in environmental conditions that are near impossible to reproduce on Earth. Studying them enhances our understanding of chemical and thermal processes, atmospheric dynamics and cloud formation. Understanding their origins can also help us improve planetary formation and evolution models.
To find out, we need to learn more about exoplanet compositions by observing their atmospheres.
There are twomain methodsto study exoplanet atmospheres. In the transit method, we can pick up stellar light that is filtered through the exoplanet’s atmosphere when it passes in front of its star, revealing the fingerprints of any chemical elements that exist there.
The other method to investigate a planet is during an “eclipse”, when it passes behind its host star. Planets also emit and reflect a small fraction of light, so by comparing the small changes in the total light when the planet is hidden and visible, we can extract the light coming from the planet.
Both types of observations are performed at different wavelengths, or colours, and since chemical elements and compounds absorb and emit at very specific wavelengths, a spectrum (light broken down by wavelength) can be produced for the planet to infer the composition of its atmosphere.
Dr. Krishna Kumari Challa
X-factor to help antibiotics regain their spark
Feb 28, 2021
Dr. Krishna Kumari Challa
Researchers find a single-celled slime mold with no nervous system that remembers food locations
Having a memory of past events enables us to take smarter decisions about the future. Researchers now identified the basis for forming memories in the slime mold Physarum polycephalum—despite its lack of a nervous system.
The ability to store and recover information gives an organism a clear advantage when searching for food or avoiding harmful environments, and has been traditionally linked to organisms that have a nervous system. A new study challenges this view by uncovering the surprising abilities of a highly dynamic,single-celled organism to store and retrieve information about its environment.
The slime mold Physarum polycephalum has been puzzling researchers for many decades. Existing at the crossroads between the kingdoms of animals, plants and fungi, this unique organism provides insight into the early evolutionary history of eukaryotes. Its body is a giant single cell made up of interconnected tubes that form intricate networks. This single amoeba-like cell may stretch several centimeters or even meters, featuring as the largest cell on earth in the Guinness Book of World Records.
The striking abilities of the slime mold to solve complex problems such as finding the shortest path through a maze earned it the attribute "intelligent," intrigued the research community and kindled questions about decision making on the most basic levels of life. The decision-making ability of Physarum is especially fascinating given that its tubular network constantly undergoes fast reorganization—growing and disintegrating its tubes—while completely lacking an organizing center. The researchers discovered that the organism weaves memories of food encounters directly into the architecture of the network-like body and uses the stored information when making future decisions.
Researchers followed the migration and feeding process of the organism and observed a distinct imprint of a food source on the pattern of thicker and thinner tubes of the network long after feeding. Given P. polycephalum's highly dynamic network reorganization, the persistence of this imprint sparked the idea that the network architecture itself could serve as memory of the past.
The researchers combined microscopic observations of the adaption of the tubular network with theoretical modeling. An encounter with food triggers the release of a chemical that travels from the location where food was found throughout the organism and softens the tubes in the network, making the whole organism reorient its migration towards the food.
The gradual softening is where the existing imprints of previous food sources come into play and where information is stored and retrieved. Past feeding events are embedded in the hierarchy of tube diameters, specifically in the arrangement of thick and thin tubes in the network. For the softening chemical that is now transported, the thick tubes in the network act as highways in traffic networks, enabling quick transport across the whole organism. Previous encounters imprinted in the network architecture weigh into the decision about the future direction of migration.
Mirna Kramar et al. Encoding memory in tube diameter hierarchy of living flow network, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2007815118
https://phys.org/news/2021-02-single-celled-slime-mold-nervous-food...
Mar 1, 2021
Dr. Krishna Kumari Challa
Caterpillar silences tomato's cry for help, scientists find
"Silencing the alarm."
Scientists found that a caterpillar called the tomato fruit worm not only chomps on tomatoes and their leaves, but also deposits enzyme-laden saliva on the plant, interfering with its ability to cry for help.
It has been shown time and time again that when under attack, plants can emit chemical distress signals, causing their peers to mount some sort of defense. A classic example is the smell of a freshly mown lawn, which prompts the release of protective compounds in nearby blades of grass that have yet to be cut.
In some cases, plant distress signals can even summon help from other species. That's what happens with the tomato. When caterpillars nibble on the plant's leaves, the leaf pores release volatile chemicals that are detected by a type of parasite: a wasp that lays eggs inside caterpillars.
So can the caterpillars strike back? In a series of experiments, researchers found that the answer was yes, illustrating a previously unknown strategy in nature's age-old contest between predator and prey.
The key is the enzyme in the caterpillar's saliva, which inhibits the opening of pores in tomato-plant leaves. That means the leaves are less able to release the distress signals, and presumably less able to attract wasps that could come to the rescue.
Po‐An Lin et al. Silencing the alarm: an insect salivary enzyme closes plant stomata and inhibits volatile release, New Phytologist (2021). DOI: 10.1111/nph.17214
https://phys.org/news/2021-02-horror-movie-caterpillar-silences-tom...
Mar 1, 2021
Dr. Krishna Kumari Challa
Swift Links Neutrino to Star-destroying Black Hole
Mar 1, 2021
Dr. Krishna Kumari Challa
https://fb.watch/3Yp8kldIDt/
A single male lyrebird can mimic the sound of an entire flock
The masters of imitation appear to have vocal talents more profound than previously appreciated
Mar 1, 2021
Dr. Krishna Kumari Challa
Coronavirus transmission through the placenta: Baby infected with coronavirus in the womb
A pregnant woman with suspected COVID-19 was rushed by ambulance to Skåne University Hospital, in Malmo, Sweden, suffering from sudden severe abdominal pain. The doctors noticed that the unborn infant had an abnormally low heart rate, which can be a sign that the baby is not getting enough oxygen.
The doctors performed an emergency caesarean section and delivered the baby within minutes. Blood tests from the baby confirmed it had severely low oxygen, and throat swabs showed that both mother and baby were suffering from COVID.
Using throat swabs from the mother and the newborn, the genome of the virus was sequenced to confirm the possibility that the infant had been infected with COVID while still in the womb.
a few days later, new genetic sequencing showed that the baby’s virus population had changed and contained a mutated version of the virus along with the original virus strain from the mother. To the best of our knowledge, this is the first case of a genetic change of the coronavirus in the unique setting of mother-to-foetus transmission before birth.
Although it is common for viruses to mutate, this mutation (called A107G) happened just five days after the baby was delivered. The genetic changes may have been stimulated by the baby coming in contact with the external environment outside the mother’s womb. However, it was surprising how quickly this single mutation occurred.
The most important findings were the changes seen in the placenta. The placenta takes blood and nutrients to the foetus and takes away waste and is critical for the growth and wellbeing of the foetus. Half the tissue was damaged. There was widespread inflammation, and coronavirus protein was found on both the mother’s and foetus’s side of the placenta. Also found was coronavirus protein in all areas that were damaged by inflammation.
with thousands of pregnant women infected worldwide, mother-to-baby transmission in the womb seems to be a rare complication of COVID during pregnancy.
Scientists think that this is because of the placental barrier that protects the baby in the womb from most infections. Also, the vital receptor needed for coronavirus entry into cells, called an ACE-2 receptor, only exists in low levels in the placenta.
In rare cases, coronavirus can damage the placenta – leading to a lack of oxygen in the unborn child – even if the mother has a mild case of COVID in late pregnancy.
we should rethink how we monitor pregnant women who have COVID, and they should be considered a more important risk group than we do today.
https://theconversation.com/baby-infected-with-coronavirus-in-the-w...
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Mar 2, 2021
Dr. Krishna Kumari Challa
Carbon Capture Research
Mar 2, 2021
Dr. Krishna Kumari Challa
Huge, Global Study of Plastic Toys Finds Over 100 Substances That May Harm Children
The potential health risks of chemicals used in plastic toys have had scientists concerned for years, but new research reveals just how widespread the risk of harm to children remains.
In an international study, researchers assessed the chemical compositions of toys and estimated levels of human exposure to the substances, ultimately finding over 100 "Chemicals of Concern" in plastic toy materials that could pose a non-negligible health risk to children.
Out of 419 chemicals found in hard, soft, and foam plastic materials used in children toys, researchers identified 126 substances that can potentially harm children's health either via cancer or non-cancer effects, including 31 plasticisers, 18 flame retardants, and 8 fragrances.
According to the researchers, while laws in many countries regulate the use of certain potentially toxic chemicals in plastic toys, there is no consistent approach internationally, and current protections don't adequately prohibit the vast extent of potentially harmful substances that toys are made from
In addition, some toxic and banned additives are still found in plastic toys also on regulated markets, for example in case of recycling contaminated plastics, unawareness by producers, or absence of regulations in the producing country.
https://www.sciencedirect.com/science/article/pii/S0160412020321498
https://www.sciencealert.com/plastic-toy-study-finds-over-100-subst...
Mar 2, 2021
Dr. Krishna Kumari Challa
Biomass-based plastics
Mar 3, 2021
Dr. Krishna Kumari Challa
The Oldest Known Mummification 'Recipe' Has Been Unearthed, And It's Intense
In an exciting discovery, researchers have discovered an original 'how to' manual, hidden inside an ancient text, which explains the crucial steps to embalming and creating a mummy.
The guide to mummification has been found on a 3,500-year-old piece of papyrus called the Papyrus Louvre-Carlsberg manuscript, so called because half of it, primarily containing medical information.
Among the details that Schiødt has teased out of the document is a list of instructions for embalming the face of the deceased person, which was done with a piece of red linen coated in a special plant-based solution.
The solution included aromatic substances as well as binders for holding the mixture together, and the saturated cloth was intended to keep the face protected from insects and bacteria while also smelling sweet. This process hasn't been documented before, but does match up with some of the mummified remains that have been found.
This manuscript also lays out the full 70-day schedule for embalming, split into two halves: a 35-day drying period and a 35-day wrapping period, which were themselves divided into four-day intervals. Common treatments to the body included applying a mixture called natron, after the removal of the organs and the brain.
https://news.ku.dk/all_news/2021/02/ancient-egyptian-manual-reveals...
https://www.sciencealert.com/the-oldest-known-mummification-recipe-...
Mar 3, 2021
Dr. Krishna Kumari Challa
People Are Accidentally Poisoning Themselves Trying to Treat COVID With a Horse Drug
People are trying to treat and prevent COVID-19 by taking ivermectin, a medication commonly used to de-worm horses – and they are poisoning themselves in the process.
The buzz around ivermectin has been generated by the FLCCC, the Front Line COVID-19 Critical Care Alliance (FLCCC), which formed at the start of the pandemic. It comprises critical care workers who previously bonded over the controversial use of vitamin C for sepsis, MedPage Today reported.
US regulators say there is not enough robust evidence or safety data to recommend ivermectin as a cure, treatment, or preventative medicine for COVID-19.
While the FLCCC has held press conferences saying studies show the drug could fight against the novel coronavirus, public health agencies and many experts say the research is lacking.
Ivermectin can be tolerated in small doses but can poison an adult in large quantities
https://www.businessinsider.com.au/coronavirus-people-are-accidenta...
Mar 3, 2021
Dr. Krishna Kumari Challa
Structure and dynamics of key receptor in migraine pain determined, paving way for better treatment options
A research team determined the shape and kinetics of an important cell surface (membrane) receptor called calcitonin gene-related peptide (CGRP), which has long been implicated in migraine. The researchers determined the structure of the receptor alone and in combination with its natural target molecule (CGRP). This gives us a clear understanding of how the receptor works during its normal function in the body. The work has been published in the journal Science.
Future studies will expand the investigations towards potential drug targets.
Tracy M. Josephs et al. Structure and dynamics of the CGRP receptor in apo and peptide-bound forms, Science (2021). DOI: 10.1126/science.abf7258
Migraine is more than a simple headache; more than 3 million migraineurs—more than 60% of whom are women—have at least one attack per year. A smaller subset experience chronic migraine, defined by migraine pain that occurs 15 days or more per month, for three or months in a row. While sufferers experience many different symptoms of varying intensity—usually nausea, dizziness, sensitivity to light and sound, and intense pain on one or both sides of the head—the physiological process of migraine onset and pain is different from other types of headache, such as muscle tension or sinus pain. While migraine was long believed to be a neurovascular disorder that involved dilation of vessels in the skull, face and cerebral membrane, research has excluded vasodilation as a factor in this type of pain. More recent work has identified increased CGRP in the trigeminal se... that results in headache.
https://medicalxpress.com/news/2021-03-dynamics-key-receptor-migrai...
Mar 4, 2021
Dr. Krishna Kumari Challa
Animals fake death for long periods to escape predators
Many animals feign death to try to escape their predators, with some individuals in prey species remaining motionless, if in danger, for extended lengths of time.
Charles Darwin recorded a beetle that remained stationary for 23 minutes—however the University of Bristol has documented an individual antlion larvae pretending to be dead for an astonishing 61 minutes. Of equal importance, the amount of time that an individual remains motionless is not only long but unpredictable. This means that a predator will be unable to predict when a potential prey item will move again, attract attention, and become a meal.
Predators are hungry and cannot wait indefinitely. Similarly, prey may be losing opportunities to get on with their lives if they remain motionless for too long. Thus, death-feigning might best be thought of as part of a deadly game of hide and seek in which prey might gain most by feigning death if alternative victims are readily available.
The study, published today in science journal Biology Letters, involved evaluating the benefits of death-feigning in terms of a predator visiting small populations of conspicuous prey. Researchers used computer simulations that utilise the marginal value theorem, a classical model in optimization.
Hide-and-seek strategies and post-contact immobility, Biology Letters (2021). royalsocietypublishing.org/doi … .1098/rsbl.2020.0892
https://phys.org/news/2021-03-animals-fake-death-periods-predators....
Mar 4, 2021
Dr. Krishna Kumari Challa
Color blindness-correcting contact lenses
Imagine seeing the world in muted shades—gray sky, gray grass. Some people with color blindness see everything this way, though most can't see specific colors. Tinted glasses can help, but they can't be used to correct blurry vision. And dyed contact lenses currently in development for the condition are potentially harmful and unstable. Now, in ACS Nano, researchers report infusing contact lenses with gold nanoparticles to create a safer way to see colors.
Color blindness-correcting contact lenses
Imagine seeing the world in muted shades—gray sky, gray grass. Some people with color blindness see everything this way, though most can't see specific colors.
Now researchers report infusing contact lenses with gold nanoparticles to create a safer way to see colors.
Some daily activities, such as determining if a banana is ripe, selecting matching clothes or stopping at a red light, can be difficult for those with colour blindness. Most people with this genetic disorder have trouble discriminating red and green shades, and red-tinted glasses can make those colors more prominent and easier to see. However, these lenses are bulky and the lens material cannot be made to fix vision problems. Thus, researchers have shifted to the development of special tinted contact lenses. Although the prototype hot-pink dyed lenses improved red-green color perception in clinical trials, they leached dye, which led to concerns about their safety. Gold nanocomposites are nontoxic and have been used for centuries to produce "cranberry glass" because of the way they scatter light.
To make the contact lenses, the researchers evenly mixed gold nanoparticles into a hydrogel polymer, producing rose-tinted gels that filtered light within 520-580 nm, the wavelengths where red and green overlap. The most effective contact lenses were those with 40 nm-wide gold nano particles, because in tests, these particles did not clump or filter more color than necessary. In addition, these lenses had water-retention properties similar to those of commercial ones and were not toxic to cells growing in petri dishes in the lab. Finally, the researchers directly compared their new material to two commercially available pairs of tinted glasses, and their previously developed hot-pink dyed contact lens. The gold nanocomposite lenses were more selective in the wavelengths they blocked than the glasses. The new lenses matched the wavelength range of the dyed contact lenses, suggesting the gold nanocomposite ones would be suitable for people with red-green color issues without the potential safety concerns. The researchers say that the next step is to conduct clinical trials with human patients to assess comfort.
Ahmed E. Salih et al. Gold Nanocomposite Contact Lenses for Color Blindness Management, ACS Nano (2021). DOI: 10.1021/acsnano.0c09657
https://phys.org/news/2021-03-blindness-correcting-contact-lenses.h...
Mar 4, 2021
Dr. Krishna Kumari Challa
How 'green' are environmentally friendly fireworks?
Fireworks are used in celebrations around the world, including Independence Day in the U.S., the Lantern Festival in China and the Diwali Festival in India. However, the popular pyrotechnic displays emit large amounts of pollutants into the atmosphere, sometimes causing severe air pollution. Now, researchers reporting in ACS' Environmental Science & Technology have estimated that, although so-called environmentally friendly fireworks emit 15-65% less particulate matter than traditional fireworks, they still significantly deteriorate air quality.
Environmentally friendly fire works aren’t really that friendly!
Fireworks are used in celebrations around the world. However, the popular pyrotechnic displays emit large amounts of pollutants into the atmosphere, sometimes causing severe air pollution. Now, researchers reporting in ACS' Environmental Science & Technology have estimated that, although so-called environmentally friendly fireworks emit 15-65% less particulate matter than traditional fireworks, they still significantly deteriorate air quality.
Fireworks displays can cause health problems, such as respiratory ailments, because they release high levels of air pollutants, including particulate matter (PM), sulfur dioxide, heavy metals and perchlorates. As a result, some cities have banned their use. But because the displays are an important aspect of many traditional celebrations, researchers and manufacturers have tried to develop more environmentally friendly pyrotechnics, including those with smokeless charges and sulfur-free propellants. Although research suggests that these fireworks emit less pollutants, their impact on air quality has not been evaluated.
Now researchers wanted to see how green these fire works are.
The researchers estimated emissions of PM2.5, which is PM with a diameter of 2.5 μm and smaller, from the 160,000 environmentally friendly fireworks set off during the display, as well as emissions from traditional fireworks. They used information on the wind direction, wind speed, temperature and chemical composition of the fireworks to simulate the size, trajectory and peak PM2.5 values for the smoke plume resulting from the event. Then, they compared their simulated values with actual data on PM2.5 concentrations measured at 75 monitoring stations throughout the city following the fireworks display.
In agreement with the team's predictions, the data showed that the fireworks smoke plume began as a narrow band that traveled northward before being fully dispersed, with peak PM2.5 levels similar to the predictions. The researchers used their validated simulation to estimate that the use of environmentally friendly fireworks produces a much smaller, shorter-lasting plume, with 15-65% of the PM2.5 emissions of a display using traditional fireworks. However, the peak concentration of PM2.5 still greatly exceeds WHO guidelines.
This led the researchers to conclude that the number of "green" fireworks used at one time should be restricted.
"Are Environmentally Friendly Fireworks Really "Green" for Air Quality? A Study from the 2019 National Day Fireworks Display in Shenzhen" Environmental Science & Technology (2021). pubs.acs.org/doi/abs/10.1021/acs.est.0c03521
Mar 4, 2021
Dr. Krishna Kumari Challa
Expect more extreme short-duration thunderstorms caused by global w...
Climate experts have revealed that rising temperatures will intensify future rainfall extremes at a much greater rate than average rainfall, with largest increases to short thunderstorms.
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How do you know where volcanic ash will end up?
When the Eyjafjallajökull volcano in Iceland erupted in April 2010, air traffic was interrupted for six days and then disrupted until May. Until then, models from the nine Volcanic Ash Advisory Centres (VAACs) around the world, which aimed at predicting when the ash cloud interfered with aircraft routes, were based on the tracking of the clouds in the atmosphere.
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New approach to removing toxins from wastewater
The New York State Center for Clean Water Technology (CCWT) at Stony Brook University has made a series of critical discoveries regarding a new approach to protecting Long Island's drinking water, groundwater, and surface waters. Some of the discoveries involve the likely human carcinogen, 1,4-dioxane, which has been found at higher levels in Long Island drinking water than anywhere else in the U.S.
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Think all your plastic is being recycled? New research shows it can...
We all know it's wrong to toss your rubbish into the ocean or another natural place. But it might surprise you to learn some plastic waste ends up in the environment, even when we thought it was being recycled.
Mar 4, 2021
Dr. Krishna Kumari Challa
Think all your plastic is being recycled? New research shows it can end up in the ocean
Some plastic waste ends up in the environment, even when we thought it was being recycled. Plastic waste most commonly leaks into the environment at the country to which it's shipped. Plastics which are of low value to recyclers, such as lids and polystyrene foam containers, are most likely to end up polluting the environment.
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Plastic waste collected for recycling is often sold for reprocessing in Asia. There, the plastics are sorted, washed, chopped, melted and turned into flakes or pellets. These can be sold to manufacturers to create new products.
The global recycled plastics market is dominated by two major plastic types:
polyethylene terephthalate (PET), which in 2017 comprised 55% of the recyclable plastics market. It's used in beverage bottles and takeaway food containers and features a "1" on the packaging
high-density polyethylene (HDPE), which comprises about 33% of the recyclable plastics market. HDPE is used to create pipes and packaging such as milk and shampoo bottles, and is identified by a "2."
The next two most commonly traded types of plastics, each with 4% of the market, are:
The remaining plastic types comprise polyvinyl chloride (3), polystyrene (6), other mixed plastics (7), unmarked plastics and "composites." Composite plastic packaging is made from several materials not easily separated, such as long-life milk containers with layers of foil, plastic and paper.
This final group of plastics is not generally sought after as a raw material in manufacturing, so has little value to recyclers.
https://theconversation.com/think-all-your-plastic-is-being-recycle...
Mar 4, 2021
Dr. Krishna Kumari Challa
Coronavirus: what happens when a person is simultaneously infected with two variants?
Scientists in Brazil recently reported that two people were simultaneously infected with two different variants of SARS-CoV-2, the virus that causes COVID-19. This co-infection seemed to have no effect on the severity of patients’ illness, and both recovered without needing to be hospitalised.
Although this is one of the few such cases recorded with SARS-CoV-2 – and the study is yet to be published in a scientific journal – scientists have observed infections with multiple strains with other respiratory viruses, such as influenza. This has raised questions about how these viruses may interact in an infected person, and what it could mean for generating new variants.
The detection of multiple variants in a person could be the result of co-infection by the different variants, or the generation of mutations within the patient after the initial infection. One way to discriminate these two scenarios is by comparing the sequences of the variants circulating in the population with those in the patient. In the Brazilian study mentioned above, the variants identified corresponded to different lineages that had been previously detected in the population, implying co-infection by the two variants.
It is important to note that this requires the two viruses to infect the same cell. Even if a person is infected with several variants, if they replicate in different parts of the body, they will not interact with each other. Indeed, this was seen in patients, where different quasi-species of coronaviruses were found in the upper and lower respiratory tracts, suggesting that viruses in these sites were not directly mixing with each other.
The evidence so far does not suggest that infection with more than one variant leads to more severe disease. And although possible, very few cases of co-infection have been reported. More than 90% of the infections in the UK currently are by B117 – the so-called Kent variant. With such a high prevalence of one variant in the population, co-infections are not likely to occur. Still, monitoring this landscape allows scientists to track the emergence of these new variants of concern and understand and respond to any changes in their transmission or vaccine efficacy.
https://theconversation.com/coronavirus-what-happens-when-a-person-...
Mar 4, 2021
Dr. Krishna Kumari Challa
Velcro-like cellular proteins key to tissue strength
Where do bodily tissues get their strength? New CU Boulder research provides important new clues to this long-standing mystery, identifying how specialized proteins called cadherins join forces to make cells stick and stay stuck together. The findings, publishing this week in the Proceedings of the National Academy of Sciences, could lead to more life-like artificial tissues and tumor busting drugs. Better understanding these proteins allows for the design of more effective engineered tissues that better mimic biological materials as well as cancer therapeutics that are more efficient and target-specific.
For example: If a cancer treatment could block a specific interaction of these cadherin proteins, it could potentially slow tumor growth by stopping or slowing the formation of new blood vessels in tumors.
Cadherin proteins are important in our bodies because they facilitate the binding and adhesion of cells in neural, cardiac, placental and skin tissues, among others, helping them maintain their function and shape.
These large, rod-like proteins in the cell membrane mediate information between the inside and outside of the cell. Where they stick out, they can bond with other cadherin proteins from the same cell, as well as those from other cells.
Like Velcro, the study found, the more pieces stick together, the stronger the bond and the longer it lasts. This amplified strength not only between proteins which exist on the same cell, but between proteins located on different cells—creating bonds 30 times stronger than the sum of their individual strengths. And once the bonding begins, these bonds become progressively stronger and stronger.
https://www.pnas.org/content/118/10/e2019845118
https://www.colorado.edu/today/2021/03/01/velcro-cellular-proteins-...
Mar 5, 2021
Dr. Krishna Kumari Challa
Researchers discover new way to halt excessive inflammation
Researchers have discovered a new way to 'put the brakes' on excessive inflammation by regulating a type of white blood cell that is critical for our immune system. The discovery has the potential to protect the body from unchecked damage caused by inflammatory diseases.
Excessive inflammation is a prominent feature of many diseases such as multiple sclerosis, arthritis and inflammatory bowel diseases.
When immune cells (white blood cells) in our body called macrophages are exposed to potent infectious agents, powerful inflammatory proteins known as cytokines are produced to fight the invading infection. However, if these cytokine levels get out of control, significant tissue damage can occur.
The researchers have found that a protein called Arginase-2 works through the energy source of macrophage cells, known as mitochondria, to limit inflammation. Specifically they have shown for the first time that Arginase-2 is critical for decreasing a potent inflammatory cytokine called IL-1.
This discovery could allow researchers to develop new treatments that target the Arginase-2 protein and protect the body from unchecked damage caused by inflammatory diseases.
Nature Communications (2021). DOI: 10.1038/s41467-021-21617-2
https://medicalxpress.com/news/2021-03-halt-excessive-inflammation....
Mar 6, 2021
Dr. Krishna Kumari Challa
'Fungal ghosts' protect skin, fabric from toxins, radiation
The idea of creating selectively porous materials has captured the attention of chemists for decades. Now, new research from Northwestern University shows that fungi may have been doing exactly this for millions of years.
When scientists set out to synthesize melanin that would mimic that which was formed by certain fungi known to inhabit unusual, hostile environments including spaceships, dishwashers and even Chernobyl, they did not initially expect the materials would prove highly porous— a property that enables the material to store and capture molecules.
Journal of the American Chemical Society
https://phys.org/news/2021-03-fungal-ghosts-skin-fabric-toxins.html...
Mar 6, 2021
Dr. Krishna Kumari Challa
An intelligent soft material that curls under pressure or expands when stretched
Mar 6, 2021
Dr. Krishna Kumari Challa
This is a fact!
Many women complain that they 're not being considered or overlooked for awards and prizes including the Nobel prize (1) in science just because of their gender. I recently found an interesting thing. I got a national award for science communication. During the award giving ceremony, Indian science and Tech secretary told us an interesting story.
Department of Science and Technology, India, gives prizes for the best PhD write up to train and make the budding scientists better at science communication. This year, they removed the names before sending the articles for assessment. And magic, magic, magic, magic. All the prize winners are women! Not even a single man got it.
What did we learn from it? Patriarchal mindsets are definitely impeding womens' chances of winning awards and prizes in science! Once you change the situation where there is no way to learn for the judge whether the person who is being judged is male or female, there is a better chance for women to win!
Footnotes:
1. Why more women don’t win Nobel prizes in science
Mar 6, 2021
Dr. Krishna Kumari Challa
Eyeless roundworms sense color
Roundworms don't have eyes or the light-absorbing molecules required to see. Yet, new research shows they can somehow sense color. The study, published on March 5 in the journal Science, suggests worms use this ability to assess the risk of feasting on potentially dangerous bacteria that secrete blue toxins. The researchers pinpointed two genes that contribute to this spectral sensitivity and are conserved across many organisms, including humans.
So a 1 mm tiny worm, Caenorhabditis elegans, with neither eyes nor the molecular machinery used by eyes to detect colors can identify and avoid a toxic bacterium based, in part, on its blue color! They can smell, taste, sense touch, react to temperature, and even escape or change their feeding patterns in response to bright, blue light.
https://news.mit.edu/2021/eyeless-roundworms-sense-color-0304
Mar 7, 2021
Dr. Krishna Kumari Challa
Scientists read 300-year-old letters without opening them
The letters had been folded using a mysterious technique.
Unopened letters more than 300 years old that were folded using mysterious techniques have now been read for the first time without opening them, a new study finds.
For centuries, before mass-produced envelopes started proliferating in the 1830s, most letters across the globe were sent using letterlocking, a method of folding letters to become their own envelopes. These intricate techniques also often served to help recipients detect if mail had been tampered with.
For example, during research in the Vatican Secret Archives, conservator Jana Dambrogio at the MIT Libraries unearthed Renaissance letters with odd slits and sliced-off corners. She discovered these were signs these documents were originally locked with a slice of paper slid through a slit and closed with a wax seal. Such letters could not be opened without ripping the paper, which would reveal to intended recipients if someone else had read the letters first.
After studying 250,000 historical letters, Dambrogio and her colleagues devised the first system to categorize letterlocking techniques, a kind of periodic table based on how these strategies creased sheets. "Letterlocking is a 10,000-year-old technology -- as long as people have tried to build security into their correspondences, you've had letterlocking, from cuneiform tablets all the way to bitcoin paper wallets.
Until now, scientists could only read these "letterpackets" by cutting them open, often damaging the documents. Although such work naturally focused on the letter's contents, this came at the cost of research into letterlocking itself, about which much remains unknown. "These folding sequences, they're just like a sneeze -- they're ephemeral. The minute you open them, you lose evidence of them.
Now scientists have devised a way to both read letterlocked texts without opening them and reconstruct the complex folds, tucks and slits used to secure them.
The scientists investigated the Brienne Collection, a postmaster's trunk holding more than 3,000 undelivered letters, including 577 letterpackets that were never opened. The letters were sent from all over Europe to The Hague between 1680 and 1706, the era that saw the Salem witch trials unfold, Newton reveal his laws of motion and gravitation, and Louis XIV move his court to Versailles.
The researchers first analyzed four letterpackets with high-resolution X-ray scans to generate 3D models of the documents. Next, they used a new computational algorithm to identify and separate different layers of the folded letters and recognize text written on them. Finally, the algorithm virtually unfolded the letters, not only making the writing visible, but also recording the crease patterns so the researchers could re-create the letterlocking process step by step.
This new strategy helped the scientists read unopened letterlocked text for the first time.
https://www.nature.com/articles/s41467-021-21326-w
Mar 8, 2021
Dr. Krishna Kumari Challa
Scientists discover why blood type may matter for COVID infection
A new study provides further evidence that people with certain blood types may be more likely to contract COVID-19.
Specifically, it found that the new coronavirus (SARS-CoV-2) is particularly attracted to the blood group A antigen found on respiratory cells.
The researchers focused on a protein on the surface of the SARS-CoV-2 virus called the receptor binding domain (RBD), which is the part of the virus that attaches to the host cells. That makes it an important target for scientists trying to learn how the virus infects people.
In this laboratory study, the team assessed how the SARS-CoV-2 RBD interacted with respiratory and red blood cells in A, B and O blood types.
The results showed that the SARS-CoV-2 RBD had a strong preference for binding to blood group A found on respiratory cells, but had no preference for blood group A red blood cells, or other blood groups found on respiratory or red cells.
The SARS-CoV-2 RBD's preference to recognize and attach to the blood type A antigen found in the lungs of people with blood type A may provide insight into the potential link between blood group A and COVID-19 infection, according to the authors of the study. It was published March 3 in the journal Blood Advances.
https://ashpublications.org/bloodadvances/article/5/5/1305/475250/T...
https://medicalxpress.com/news/2021-03-scientists-blood-covid-infec...
Mar 8, 2021
Dr. Krishna Kumari Challa
Astrocytes derived from patients with bipolar disorder malfunction
Brain cells called astrocytes derived from the induced pluripotent stem cells of patients with bipolar disorder offer suboptimal support for neuronal activity. In a paper in the journal Stem Cell Reports, researchers show that this malfunction can be traced to an inflammation-promoting molecule called interleukin-6 (IL-6), which is secreted by astrocytes. The results highlight the potential role of astrocyte-mediated inflammatory signaling in the psychiatric disease, although further investigation is needed.
Mar 8, 2021
Dr. Krishna Kumari Challa
Artificial ‘brain’ reveals why we can’t always believe our eyes
Mar 8, 2021
Dr. Krishna Kumari Challa
Researchers have captured the first detailed images of newborn babies’ lungs as they take their first breaths.
Mar 8, 2021
Dr. Krishna Kumari Challa
Economic benefits of protecting nature now outweigh those of exploiting it, global data reveal
The economic benefits of conserving or restoring natural sites "outweigh" the profit potential of converting them for intensive human use, according to the largest-ever study comparing the value of protecting nature at particular locations with that of exploiting it.
A research team analysed dozens of sites—from Kenya to Fiji and China to the UK—across six continents. A previous breakthrough study in 2002 only had information for five sites.
For the latest study, scientists calculated the monetary worth of each site's "ecosystem services", such as carbon storage and flood protection, as well as likely dividends from converting it for production of goods such as crops and timber.
The team initially concentrated on 24 sites and compared their "nature-focused" and "alternative" states by working out the annual net value of a range of goods and services for each site under each state, then projected the data over the next 50 years.
A major economic benefit of natural habitats comes from their regulation of the greenhouse gases driving climate change, including the sequestration of carbon.
The economic consequences of conserving or restoring sites for nature, Nature Sustainability (2021). DOI: 10.1038/s41893-021-00692-9 , dx.doi.org/10.1038/s41893-021-00692-9
https://phys.org/news/2021-03-economic-benefits-nature-outweigh-exp...
Mar 9, 2021
Dr. Krishna Kumari Challa
Do photosynthetic complexes use quantum coherence to increase their...
In a new report now published on Science Advances, Elinor Zerah Harush and Yonatan Dubi in the departments of chemistry and nanoscale science and technology, at the Ben-Gurion University of the Negev, Israel, discussed a direct evaluation of the effects of quantum coherence on the efficiency of three natural photosynthetic complexes. The open quantum systems approach allowed the researchers to simultaneously identify the quantum-nature and efficiency under natural physiological conditions. These systems resided in a mixed quantum-classical regime, which they characterized using dephasing-assisted transport. The efficiency was minimal at best therefore the presence of quantum coherence did not play a substantial role in the process. The efficiency was also independent of any structural parameters, suggesting the role of evolution during structural design for other uses.
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How the growth of ice depends on the fluid dynamics underneath
Researchers of the Toschi group of Eindhoven University of Technology think the water phase change problem with considering the water density anomaly is of great importance relating to common natural phenomena. Their research plan is firstly to understand the physics fundamentals, that is, the coupled problem of the stably and unstably stratified layers with considering the density anomaly.
Mar 9, 2021
Dr. Krishna Kumari Challa
At Dubai airport, travelers' eyes become their passports
Dubai's airport, the world's busiest for international travel, can already feel surreal, with its cavernous duty-free stores, artificial palm trees, gleaming terminals, water cascades and near-Arctic levels of air conditioning.
Now, the key east-west transit hub is rolling out another addition from the realm of science fiction—an iris-scanner that verifies one's identity and eliminates the need for any human interaction when entering or leaving the country.
That's because the airport debuted a new "smart tunnel" that uses biometric technology, instead of human checks, to allow some air travelers to complete passport control in just 15 seconds.
It's the latest artificial intelligence program the United Arab Emirates has launched amid the surging coronavirus pandemic, contact-less technology the government promotes as helping to stem the spread of the virus. But the efforts also have renewed questions about mass surveillance in the federation of seven sheikhdoms, which experts believe has among the highest per capita concentrations of surveillance cameras in the world.
Dubai's airport started offering the program to all passengers last month. On Sunday, travelers stepped up to an iris scanner after checking in, gave it a good look and breezed through passport control within seconds. Gone were the days of paper tickets or unwieldy phone apps.
In recent years, airports across the world have accelerated their use of timesaving facial recognition technology to move passengers to their flights. But Dubai's iris scan improves on the more commonplace automated gates seen elsewhere, authorities said, connecting the iris data to the country's facial recognition databases so the passenger needs no identifying documents or boarding pass.
Now, all the procedures have become 'smart,' around five to six seconds
Iris biometrics are considered more reliable than surveillance cameras that scan people's faces from a distance without their knowledge or consent.
https://techxplore.com/news/2021-03-dubai-airport-eyes-passports.ht...
https://phys.org/news/2018-10-dubai-airport-biometric-tech.html
Mar 9, 2021
Dr. Krishna Kumari Challa
The challenge is to be able to identify when this may be happening. Sometimes it’s easy, as often even the most basic fact-checking and logic can be potent weapons against misinformation.
But often, it can be hard. People who are trying either to make you believe something that isn’t true, or to doubt something that is true, use a variety of strategies that can manipulate you very effectively.
These red flags can alert you ....
1.The ‘us versus them’ narrative: This is one of the most common tactics used to mislead. It taps into our intrinsic distrust of authority and paints those with evidence-based views as part of some other group that’s not be trusted.
2. ‘I’m not a scientist, but…’: People tend to use the phrase “I’m not a scientist, but…” as a sort of universal disclaimer which they feel allows them to say whatever they want, regardless of scientific accuracy.
3. Reference to ‘the science not being settled’
This is perhaps one of the most powerful strategies used to mislead.
There are of course times when the science is not settled, and when this is the case, scientists openly argue different points of view based on the evidence available.
4. Overly simplistic explanations
Oversimplifications and generalisations are where many conspiracy theories are born.
Science is often messy, complex and full of nuance. The truth can be much harder to explain, and can sometimes sound less plausible, than a simple but incorrect explanation.
We’re naturally drawn to simple explanations. And if they tap into our fears and exploit our cognitive biases — systematic errors we make when we interpret information — they can be extremely seductive.
5. Cherry-picking
People who use this approach treat scientific studies like individual chocolates in a gift box, where you can choose the ones you like and disregard the ones you don’t. Of course, this isn’t how science works.
It’s important to understand not all studies are equal; some provide much stronger evidence than others. You can’t just conveniently put all your faith in the studies that align with your views, and ignore those that don’t.
When scientists evaluate evidence, they go through a systematic process to assess the whole body of evidence. This is a crucial task that requires expertise.
The cherry-picking tactic can be hard to counter because unless you’re across all the evidence, you’re not likely to know whether the studies being presented have been deliberately curated to mislead you.
This is yet another reason to rely on the experts who understand the full breadth of the evidence and can interpret it sensibly.
https://theconversation.com/5-ways-to-spot-if-someone-is-trying-to-...
Mar 9, 2021
Dr. Krishna Kumari Challa
How to cut onions without crying using science
Mar 10, 2021
Dr. Krishna Kumari Challa
Humidity in breath makes cotton masks more effective at slowing the spread of COVID-19
Researchers have come up with a better way to test which fabrics work best for masks that are meant to slow the spread of COVID-19. By testing those fabrics under conditions that mimic the humidity of a person's breath, the researchers have obtained measurements that more accurately reflect how the fabrics perform when worn by a living, breathing person.
The new measurements show that under humid conditions, the filtration efficiency—a measure of how well a material captures particles—increased by an average of 33% in cotton fabrics. Synthetic fabrics performed poorly relative to cotton, and their performance did not improve with humidity. The material from medical-procedure masks also did not improve with humidity, though it performed in roughly the same range as cottons.
The filtration efficiency of cotton fabrics increases in humid conditions because cotton is hydrophilic, meaning it likes water. By absorbing small amounts of the water in a person's breath, cotton fibers create a moist environment inside the fabric. As microscopic particles pass through, they absorb some of this moisture and grow larger, which makes them more likely to get trapped.
Most synthetic fabrics, on the other hand, are hydrophobic, meaning they dislike water. These fabrics do not absorb moisture, and their filtration efficiency does not change in humid conditions.
Christopher D. Zangmeister et al, Hydration of Hydrophilic Cloth Face Masks Enhances the Filtration of Nanoparticles, ACS Applied Nano Materials (2021). DOI: 10.1021/acsanm.0c03319
https://phys.org/news/2021-03-humidity-cotton-masks-effective-covid...
Mar 10, 2021
Dr. Krishna Kumari Challa
Bacterial film separates water from oil
Researchers have demonstrated that a slimy, yet tough, type of biofilm that certain bacteria make for protection and to help them move around can also be used to separate water and oil. The material may be useful for applications such as cleaning contaminated waters.
They reported the findings of an experiment in which they used a material produced by the bacteria Gluconacetobacter hansenii as a filter to separate water from an oil mixture.
The biofilm the bacteria make and release into their environment is made of cellulose, which is the same material that gives plants a sturdy structure in their cell walls. However, when bacteria make cellulose, it has a tightly packed, crystalline structure. It's one of the purest, if not the purest, forms of cellulose out there. The bacteria make the film to protect themselves.
The material was effective at removing water, and it 's sturdy. The oil doesn't want to go through the membrane; it has a repulsive effect to it. It's super fat-hating.
Researchers see a variety of potential applications for the material in situations where you need to recover water from an oily mixture—whether it be to clean water contaminated with a textile dye or for environmental remediation.
Zahra Ashrafi et al. Bacterial Superoleophobic Fibrous Matrices: A Naturally Occurring Liquid-Infused System for Oil–Water Separation, Langmuir (2021). DOI: 10.1021/acs.langmuir.0c02717
https://phys.org/news/2021-03-bacterial-oil.html?utm_source=nwlette...
Mar 10, 2021
Dr. Krishna Kumari Challa
Why sea slugs cut off their own heads
Autotomy, the voluntary shedding of a body part, is common to distantly-related animals such as arthropods, gastropods, asteroids, amphibians, and lizards. Autotomy is generally followed by regeneration of shed terminal body parts, such as appendages or tails. A a new type of extreme autotomy ‘s reported recently.
Two species of sea slug, Elysia marginata and Elysia atroviridis, decapitate themselves — only to regrow a new body from the severed head. Researchers were astonished to observe slugs in captivity cutting off their own heads after their bodies became infected with parasites. Within 3 weeks, the heads regenerate a whole, parasite-free body, though the bodies never grow back new heads.
https://www.cell.com/current-biology/fulltext/S0960-9822(21)00047-6?utm_source=Nature+Briefing&utm_campaign=3d9abe9084-briefing-dy-20210309&utm_medium=email&utm_term=0_c9dfd39373-3d9abe9084-44672165
Mar 10, 2021
Dr. Krishna Kumari Challa
How trees secretly talk to each other
Mar 11, 2021
Dr. Krishna Kumari Challa
Scientists develop new magnetic nanomaterial for counterfeit money prevention
An international research team has developed a new iron-cobalt-nickel nanocomposite with tunable magnetic properties. The nanocomposite could be used to protect money and securities from counterfeiting.
The new iron-cobalt-nickel nanocomposite was obtained by chemical precipitation, followed by a reduction process.
The new composite was observed to possess high value of coercivity, which makes the technology applicable e.g. to magnetic rubbers and different magnetically coupled devices. Another potential application is protecting money and securities from counterfeiting.
Tien Hiep Nguyen et al, Impact of Iron on the Fe–Co–Ni Ternary Nanocomposites Structural and Magnetic Features Obtained via Chemical Precipitation Followed by Reduction Process for Various Magnetically Coupled Devices Applications, Nanomaterials (2021). DOI: 10.3390/nano11020341
https://phys.org/news/2021-03-scientists-magnetic-nanomaterial-coun...
Mar 11, 2021
Dr. Krishna Kumari Challa
Bacteria know how to exploit quantum mechanics, study finds
Photosynthetic organisms harvest light from the sun to produce the energy they need to survive. A new paper published by University of Chicago researchers reveals their secret: exploiting quantum mechanics.
Before this study, the scientific community saw quantum signatures generated in biological systems and asked the question, were these results just a consequence of biology being built from molecules, or did they have a purpose?" said Greg Engel, Professor of Chemistry and senior author on the study. "This is the first time we are seeing biology actively exploiting quantum effects.
The scientists studied a type of microorganism called green sulfur bacteria. These bacteria need light to survive, but even small amounts of oxygen can damage their delicate photosynthetic equipment. So they must develop ways to minimize the damage when the bacterium does encounter oxygen.
To study this process, researchers tracked the movement of energy through a photosynthetic protein under different conditions—with oxygen around, and without.
They found that the bacterium uses a quantum mechanical effect called vibronic mixing to move energy between two different pathways, depending on whether or not there's oxygen around. Vibronic mixing involves vibrational and electronic characteristics in molecules coupling to one another. In essence, the vibrations mix so completely with the electronic states that their identities become inseparable. This bacterium uses this phenomenon to guide energy where it needs it to go.
If there's no oxygen around and the bacterium is safe, the bacterium uses vibronic mixing by matching the energy difference between two electronic states in an assembly of molecules and proteins called the FMO complex, with the energy of the vibration of a bacteriochlorophyll molecule. This encourages the energy to flow through the 'normal' pathway toward the photosynthetic reaction center, which is packed full of chlorophyll.
But if there is oxygen around, the organism has evolved to steer the energy through a less direct path where it can be quenched. (Quenching energy is similar to putting a palm on a vibrating guitar string to dissipate energy.) This way, the bacterium loses some energy but saves the entire system.
Jacob S. Higgins et al, Photosynthesis tunes quantum-mechanical mixing of electronic and vibrational states to steer exciton energy transfer, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2018240118
https://phys.org/news/2021-03-bacteria-exploit-quantum-mechanics.ht...
Mar 11, 2021
Dr. Krishna Kumari Challa
Face masks are a ticking plastic timebomb
Recent studies estimate that we use an astounding 129 billion face masks globally every month—that is 3 million a minute. Most of them are disposable face masks made from plastic microfibers.
With increasing reports on inappropriate disposal of masks, it is urgent to recognize this potential environmental threat and prevent it from becoming the next plastic problem.
Disposable masks are plastic products, that cannot be readily biodegraded but may fragment into smaller plastic particles, namely micro- and nanoplastics that widespread in ecosystems.
The enormous production of disposable masks is on a similar scale as plastic bottles, which is estimated to be 43 billion per month. However, different from plastic bottles, (of which app. 25 pct. is recycled), there is no official guidance on mask recycle, making it more likely to be disposed of as solid waste
If not disposed of for recycling, like other plastic wastes, disposable masks can end up in the environment, freshwater systems, and oceans, where weathering can generate a large number of micro-sized particles (smaller than 5 mm) during a relatively short period (weeks) and further fragment into nanoplastics (smaller than 1 micrometer).
"A newer and bigger concern is that the masks are directly made from microsized plastic fibers (thickness of ~1 to 10 micrometers). When breaking down in the environment, the mask may release more micro-sized plastics, easier and faster than bulk plastics like plastic bags.
How can you solve it?
Researchers recommend these solutions:
Elvis Genbo Xu et al, Preventing masks from becoming the next plastic problem, Frontiers of Environmental Science & Engineering (2021). DOI: 10.1007/s11783-021-1413-7
https://phys.org/news/2021-03-masks-plastic-timebomb.html?utm_sourc...
Mar 11, 2021
Dr. Krishna Kumari Challa
A scarf that speaks? Scientists develop message display fabric
At first glance, the fabric looks like a pretty if not especially original scarf, with turquoise, blue and orange stripes in an open weave. But this fabric can communicate.
It's wearable, foldable and washable, but it's also a fully functioning display—capable of flashing messages or images, or even being used with a keyboard.
it could revolutionize communication and "help individuals with voice, speech or language difficulties to express themselves to others".
Large-area display textiles integrated with functional systems, Nature (2021). DOI: 10.1038/s41586-021-03295-8 , dx.doi.org/10.1038/s41586-021-03295-8
https://techxplore.com/news/2021-03-scarf-scientists-message-fabric...
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Mar 11, 2021
Dr. Krishna Kumari Challa
The Chemical Origins of Life
How did life get started on Earth? And how are we using what we know to look for it throughout the galaxy?
Mar 11, 2021
Dr. Krishna Kumari Challa
Observing the birth of a quasiparticle
Over the past decades, physicists worldwide have been trying to gain a better understanding of non-equilibrium dynamics in quantum many-body systems. Some studies investigated what are known as quasiparticles, disturbances or entities in physical systems that exhibit behavior similar to that of particles.
Researchers at Aarhus University recently carried out a study investigating the non-equilibrium dynamics of a quantum impurity immersed in a bosonic environment. Their paper, published in Nature Physics, sheds light on the dynamical behavior of interacting many-body systems, while also improving the current understanding of how Bose polarons are formed.
Quasiparticles are extremely interesting, since they may consist of countless particles and their excitations.
The idea of quasiparticles was first introduced in the 1930s by physicist Lev Landau, who was trying to gain a better understanding of complex quantum systems. The experiments carried out now build on models created by Landau.
In their studies, the researchers prepared coherent superposition states of atoms in a Bose-Einstein condensate with a small impurity-state component using an interferometric technique. Subsequently, they monitored the evolution of these quantum superpositions and their transition into polaronic quasiparticles.
Remarkably, the researchers were able to observe the birth of a unique class of quasiparticles, called Bose polarons, for the very first time. While in the past several research groups detected signs of these quasiparticles in laboratory settings, so far observing their gradual formation over time proved highly challenging, mainly because the processes through which they are formed are exceedingly fast.
Non-equilibrium quantum dynamics and formation of the Bose polaron. Nature Physics(2021). DOI: 10.1038/s41567-021-01184-5.
Bipolarons in a Bose-Einstein condensate. Physical Review Letters(2018).
DOI: 10.1103/PhysRevLett.121.013401.
Observation of attractive and repulsive polarons in a Bose-Einstein condensate. Physical Review Letters(2016). DOI: 10.1103/PhysRevLett.117.055302.
Bose polarons in the strongly interacting regime. Physical Review Letters(2016). DOI: 10.1103/PhysRevLett.117.055301.
Bose polarons near quantum criticality. Science(2020). DOI: 10.1126/science.aax5850.
https://phys.org/news/2021-03-birth-quasiparticle.html?utm_source=n...
Mar 12, 2021
Dr. Krishna Kumari Challa
Foodborne fungus impairs intestinal wound healing in Crohn's disease
Eating is a dangerous business. Naturally occurring toxins in food and potentially harmful foodborne microbes can do a number on our (injure) intestines, leading to repeated minor injuries. In healthy people, such damage typically heals in a day or two. But in people with Crohn's disease, the wounds fester, causing abdominal pain, bleeding, diarrhea and other unpleasant symptoms.
Crohn's is a subtype of inflammatory bowel disease. As the name suggests, it is driven by chronic inflammation in the digestive tract and primarily treated with immunosuppressive medications. Crohn's patients endure repeated cycles of gastrointestinal symptom flare-up and remission. During a flare, their digestive tracts are dotted with inflamed, open sores that can persist for weeks or even months.
Researchers discovered that a fungus found in foods such as cheese and processed meats can infect sites of intestinal damage in mice and people with Crohn's and prevent healing. Moreover, treating infected mice with antifungal medication eliminates the fungus and allows the wounds to heal.
The findings, published March 12 in the journal Science, suggest that antifungal drugs and dietary changes are potential new approaches to improving intestinal wound healing and reducing symptoms of Crohn's disease.
U. Jain el al., "Debaryomyces is enriched in Crohn's disease intestinal tissue and impairs healing in mice," Science (2021). science.sciencemag.org/cgi/doi … 1126/science.abd0919
https://medicalxpress.com/news/2021-03-foodborne-fungus-impairs-int...
Mar 12, 2021
Dr. Krishna Kumari Challa
The secrets of the best rainbows on Earth
Why Hawai'i the rainbow capital of the world
Rainbows are some of the most spectacular optical phenomena in the natural world
Hawai'i's location in the subtropical Pacific means the overall weather pattern is dominated by trade winds, with frequent rain showers and clear skies between the showers.
Businger outlines four additional factors affecting the prevalence of rainbows throughout the islands.
"At night a warm sea surface heats the atmosphere from below, while radiation to space cools cloud tops, resulting in deeper rain showers in the morning that produce rainbows in time for breakfast," said Businger.
Another critical factor in producing frequent rainbows is Hawai'i's mountains, which cause trade wind flow to be pushed up, forming clouds and producing rainfall. Without mountains, Hawai'i would be a desert with a scant 17 inches annual rainfall.
A third factor conducive to rainbow sightings is daytime heating, which drives island-scale circulations. During periods of lighter winds, showers form over the ridge crests over Oahu and Kauai in the afternoon, resulting in prolific rainbows as the sun sets.
Due to the remoteness of the Hawaiian Islands, the air is exceptionally clean and free of pollution, continental dust, and pollen. This is the fourth factor that contributes to the numerous bright rainbows with the full spectrum of colors.
Steven Businger, The Secrets of the Best Rainbows on Earth, Bulletin of the American Meteorological Society (2020). DOI: 10.1175/BAMS-D-20-0101.1
https://phys.org/news/2021-03-secrets-rainbows-earth.html?utm_sourc...
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Mar 12, 2021
Dr. Krishna Kumari Challa
Classic math problem solved: Computer scientists have developed a s...
One of the most classic algorithmic problems deals with calculating the shortest path between two points. A more complicated variant of the problem is when the route traverses a changing network—whether this be a road network or the internet. For 40 years, researchers have sought an algorithm that provides an optimal solution to this problem. Now, computer scientist Christian Wulff-Nilsen of the University of Copenhagen and two research colleagues have come up with a recipe.
When heading somewhere new, most of us leave it to computer algorithms to help us find the best route, whether by using a car's GPS, or public transport and map apps on their phone. Still, there are times when a proposed route doesn't quite align with reality. This is because road networks, public transportation networks and other networks aren't static. The best route can suddenly be the slowest, e.g. because a queue has formed due to roadworks or an accident.
People probably don't think about the complicated math behind routing suggestions in these types of situations. The software being used is trying to solve a variant for the classic algorithmic "shortest path" problem, the shortest path in a dynamic network. For 40 years, researchers have been working to find an algorithm that can optimally solve this mathematical conundrum. Now, Christian Wulff-Nilsen of the University of Copenhagen's Department of Computer Science has succeeded in cracking the nut along with two colleagues.
The researchers represent a network as a so-called dynamic graph. In this context, a graph is an abstract representation of a network consisting of edges, roads for example, and nodes, representing intersections, for example. When a graph is dynamic, it means that it can change over time. The new algorithm handles changes consisting of deleted edges—for example, if the equivalent of a stretch of a road suddenly becomes inaccessible due to road work.
Traditional algorithms assume that a graph is static, which is rarely true in the real world. When these kinds of algorithms are used in a dynamic network, they need to be rerun every time a small change occurs in the graph—which wastes time.
Aaron Bernstein, et al. Near-Optimal Decremental SSSP in Dense Weighted Digraphs. arXiv:2004.04496v2 [cs.DS] arxiv.org/abs/2004.04496
https://techxplore.com/news/2021-03-classic-math-problem-scientists...
Mar 12, 2021
Dr. Krishna Kumari Challa
How to spot deepfakes? Look at light reflection in the eyes
Computer scientists have developed a tool that automatically identifies deepfake photos by analyzing light reflections in the eyes.
The tool proved 94% effective with portrait-like photos in experiments described in a paper accepted at the IEEE International Conference on Acoustics, Speech and Signal Processing to be held in June in Toronto, Canada.
The cornea is almost like a perfect semisphere and is very reflective. So, anything that is coming to the eye with a light emitting from those sources will have an image on the cornea. The two eyes should have very similar reflective patterns because they're seeing the same thing. It's something that we typically don't typically notice when we look at a face.
When we look at something, the image of what we see is reflected in our eyes. In a real photo or video, the reflections on the eyes would generally appear to be the same shape and color.
However, most images generated by artificial intelligence—including generative adversary network (GAN) images—fail to accurately or consistently do this, possibly due to many photos combined to generate the fake image.
Now the researchers tool exploits this shortcoming by spotting tiny deviations in reflected light in the eyes of deepfake images.
While promising, this new technique has limitations.
For one, you need a reflected source of light. Also, mismatched light reflections of the eyes can be fixed during editing of the image. Additionally, the technique looks only at the individual pixels reflected in the eyes—not the shape of the eye, the shapes within the eyes, or the nature of what's reflected in the eyes.
Finally, the technique compares the reflections within both eyes. If the subject is missing an eye, or the eye is not visible, the technique fails.
Exposing GAN-generated Faces Using Inconsistent Corneal Specular Highlights. arXiv:2009.11924v2 [cs.CV] arxiv.org/abs/2009.11924
https://techxplore.com/news/2021-03-deepfakes-eyes.html?utm_source=...
Mar 12, 2021
Dr. Krishna Kumari Challa
Using softened wood to create electricity in homes
A multi-institutional team of researchers has found that it is possible to use a type of fungus to soften wood to the point that it could be used to generate electricity. In their paper published in the journal Science Advances, the group describes their process and how they tested it.
As the world works its way toward cleaner energy-producing systems, scientists seek novel approaches to producing electricity. One possibility is the use of piezoelectric devices that generate electricity by harnessing movement such as footsteps. In this new effort, the researchers have noted that much energy is wasted when people walk around. And while some have attempted to harness some of that energy with devices designed for shoes or legs, the researchers with this new effort wondered if it might be possible to add piezoelectrics to the floor to make use of that energy.
In studying the kinds of wood that are used to make floors, particularly in homes, the researchers noted that they do not have much give—a necessary component of an energy-harvesting system. To solve that problem, they found that applying a type of white rot fungus to pieces of balsa wood for a few weeks sped up the decaying process in a useful way. It made the wood spongier, which translated to give. When stepping on the wood, the researchers could feel it depress. They also found that after the wood returned to its former shape when pressure was removed.
To test their idea, the researchers treated a wooden veneer with the fungus and then added a piezoelectric device, which sent the power it produced through a wire attached to an LED light. The wood was then placed on a floor where people could walk on it. Each time they did so, the light came on. The researchers note that the amount of electricity generated was just 0.85 volts but the system could very easily be scaled up to include all the flooring in a home, generating enough electricity, perhaps, to power certain devices.
Jianguo Sun et al. Enhanced mechanical energy conversion with selectively decayed wood, Science Advances (2021). DOI: 10.1126/sciadv.abd9138
https://techxplore.com/news/2021-03-softened-wood-electricity-homes...
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Mar 12, 2021
Dr. Krishna Kumari Challa
How can some planets be hotter than stars? We’ve started to unravel the mystery
Data from the Kepler mission has shown that large, gaseous exoplanets can orbit very close to their star – rather than far away from it, as is the case in our Solar System, causing them to reach temperatures exceeding 1,000K (727°C). These have been dubbed “hot” or “ultra-hot” Jupiters.
But how can hot, gaseous planets form and exist so close to their star? What kind of extreme physical processes happen here? Answers to those questions have large implications in our understanding of exoplanets and solar system planets. In our recent study, published in The Astrophysical Journal Letters, we have added another piece to the puzzle of planet formation and evolution.
The hottest exoplanet known so far is Kelt-9 b, which was discovered in 2016. Kelt-9 b orbits a star that is twice as hot as our Sun, at a distance ten times closer than Mercury orbits our star. It is a large gaseous exoplanet, with a radius 1.8 times that of Jupiter and temperatures reaching 5,000K. For comparison, this is hotter than 80% of all the stars in the universe and a similar temperature to our Sun.
In essence, hot Jupiters are a window into extreme physical and chemical processes. They offer an incredible opportunity to study physics in environmental conditions that are near impossible to reproduce on Earth. Studying them enhances our understanding of chemical and thermal processes, atmospheric dynamics and cloud formation. Understanding their origins can also help us improve planetary formation and evolution models.
To find out, we need to learn more about exoplanet compositions by observing their atmospheres.
There are two main methods to study exoplanet atmospheres. In the transit method, we can pick up stellar light that is filtered through the exoplanet’s atmosphere when it passes in front of its star, revealing the fingerprints of any chemical elements that exist there.
The other method to investigate a planet is during an “eclipse”, when it passes behind its host star. Planets also emit and reflect a small fraction of light, so by comparing the small changes in the total light when the planet is hidden and visible, we can extract the light coming from the planet.
Both types of observations are performed at different wavelengths, or colours, and since chemical elements and compounds absorb and emit at very specific wavelengths, a spectrum (light broken down by wavelength) can be produced for the planet to infer the composition of its atmosphere.
Mar 12, 2021