Bubbles occur when a thin film (for example, of soapy water) traps some gas (for example, air). The molecules in the film are attracted to each other, which not only holds the film together, but also makes it shrink to the smallest possible area.
The smallest area enclosing any given volume? A sphere. Therefore, the film will shrink to cover a sphere, and then can’t shrink any further because of the trapped air. Thus, bubbles end up as round.
Protein may protect against neurodegenerative diseases
Cells translate their genetic material at rapid rates with exquisite precision to reproduce, repair damage or even combat disease. But the process can deregulate and give rise to disease. Byproducts of errant processes can build up like gunk in the gears, especially around neurons, breaking down the repair mechanisms and causing further damage and even neurodegenerative disorders such as Alzheimer's disease.
Now, an international research team may have found that a protein implicated in tumour growthmay be able to help regulate awry cellular translationand protect against neuronal decay. They published their results on July 13 in theCell Reports.
"Researchers have begun to understand that age-related neurodegenerative diseases may be caused by slow but steady accumulation of toxic peptide products, which leads to death of neurons, such as beta-amyloid plaques causing Alzheimer's disease.
Repeat-associated non-AUG (RAN) translation is one of the mechanisms that generates such toxic products."
When replicating their genetic material, cells look for specifically ordered markers that signal the spot where they should start and end the copy to make a specific protein. The signal is typically "AUG," but RAN translation doesn't need this signal and can begin processing at other points. The problem is that RAN translation can end up copying bits of repeated genetic informationthat become the toxic buildup that leads to neurodegeneration.
In diseased conditions, 5MP is a protein that can potentially transform a healthy cell into a tumor cell. In healthy conditions, 5MP mimics a protein involved in regulating RAN translation. The researchers used electron microscopy and computer-directed modeling to reveal the structure of the preinitiation complex of molecules that assemble prior to RAN translation beginning. They found that 5MP competes with the protein it mimics in human cells and, when it wins, it reduces RAN translation and its toxic byproducts.
To better understand how this finding translates todiseaseoutcomes, the researchers engineered flies with fragile X-associated tremor ataxia syndrome, aneurodegenerative disorder. They found that increasing the levels of 5MP in the affected flies repressed neuronal toxicity and enhanced their lifespan.
"Taken together, these data suggest that modulation of 5MP levels could be a viable therapeutic target by which to selectively reduce RAN translation in repeat expansion disorders
Chingakham Ranjit Singh et al, Human oncoprotein 5MP suppresses general and repeat-associated non-AUG translation via eIF3 by a common mechanism, Cell Reports (2021). DOI: 10.1016/j.celrep.2021.109376
Histamine could be a key player in depression, according to study in mice
Bodily inflammation dampens levels of a "feel-good molecule" and antidepressants' ability to boost them, according to new research in mice.
The findings, from researchers at Imperial College London and University of South Carolina, add to mounting evidence that inflammation, and the accompanying release of the molecule histamine, affects a key molecule responsible for mood in the brain—serotonin.
If replicated in humans, the findings—which identify histamine as a "new molecule of interest" in depression—could open new avenues for treating depression, which is the most common mental health problem worldwide.
Inflammation—a blanket term describing an immune response—triggers the release of histamine in the body. This increases blood flow to affected areas to flood them with immune cells. While these effects help the body fight infections, both long-term and acute inflammation is increasingly linked to depression.
Inflammation accompanies infections but can also be caused by stress, allergic responses and a host of chronic diseases such as diabetes, obesity, cancer and neurodegenerative diseases.
Melinda Hersey et al, Inflammation-Induced Histamine Impairs the Capacity of Escitalopram to Increase Hippocampal Extracellular Serotonin, The Journal of Neuroscience (2021). DOI: 10.1523/JNEUROSCI.2618-20.2021
Quantum entanglement is explained in classic terms
In many quantum measurement experiments and thought experiments, measurement results appear that do not seem to have classic explanations. As example: In quantum particle spin experiments, entangled particles appear to interact instantly across distances; and in interferometer experiments, one measurement result appears to be split over two paths. Currently, these measurement phenomena are treated as unique to quantum mechanics and not understandable in classic physics. Recognizing calibration in theory explains and resolves all the differences that appear to occur between classic and quantum measurements.
More information:M. Born (editor), The Born-Einstein Letters, page 158, Macmillan, London, 1971. "Spooky action at a distance" is a phrase Einstein applied.
J. C. Maxwell, A Treatise on Electricity and Magnetism, 3rd Edition (1891), Dover Publications, New York, 1954, page 1.
L. Euler, Elements of Algebra, Chapter I, Article I, #3. Third edition, Longman, Hurst, Rees, Orme and Co., London England, 1822. Page 1: "Now, we cannot measure or determine one quantity, except by considering some other quantity of the same kind as known, and pointing out their mutual relation."www.google.com/books/edition/E… &printsec=frontcover
Though hand-washing is proven effective in combating the spread of disease and infection, the physics behind it has rarely been studied. But in Physics of Fluids, researchers describe a simple model that captures the key mechanics of hand-washing.
By simulating hand-washing, they estimated the time scales on which particles, like viruses and bacteria, were removed from hands.
The mathematical model acts in two dimensions, with one wavy surface moving past another wavy surface, and a thin film of liquid between the two. Wavy surfaces represent hands because they are rough on small spatial scales.
Particles are trapped on the rough surfaces of the handin potential wells. In other words, they are at the bottom of a valley, and in order for them to escape, the energy from the water flow must be high enough to get them up and out of the valley.
The strength of the flowing liquid depends on the speed of the moving hands. A stronger flow removes particles more easily.
Basically, the flow tells you about the forces on the particles. Then you can work out how the particles move and figure out if they get removed.
If you move your hands too gently, too slowly, relative to one another, the forces created by the flowing fluid are not big enough to overcome the force holding the particle down.
It takes about 20 seconds of vigorous movement to dislodge potential viruses and bacteria.
Majority of climate change news coverage now accurate: study
Two decades ago, print media frequently gave equal credence to both legitimate climate experts and outlier climate deniers. But researchers found in more recent years that the media around the globe actually got it right most of the time. However, facts now outweigh a debate.
Nine out of ten media stories accurately reported the science on human contributions to climate change. It's not portrayed as a two-sided debate anymore.
Lucy McAllister et al, Balance as bias, resolute on the retreat? Updates & analyses of newspaper coverage in the United States, United Kingdom, New Zealand, Australia and Canada over the past 15 years, Environmental Research Letters (2021). DOI: 10.1088/1748-9326/ac14eb
Some 73 percent of people now believe that Earth's climate is approaching abrupt and irreversible "tipping points" due to human activity, according to a global opinion poll released on17th August, 2021.
Scientists are increasingly concerned that somefeedback loopsin nature—such as irreversible melting of icesheets or permafrost—may be close to being triggered as mankind's mind-bogglingcarbon emissionsshow no signs of slowing, despite a pandemic.
The IPCC report warned that Earth is on course to be 1.5C hotter than pre-industrial times around 2030—a full decade earlier than it projected just three years ago.
Tuesday's survey, conducted by the Global Commons Alliance and Ipsos MORI, found four out of five respondents wanted to do more to protect the planet.
The world is not sleepwalking towards catastrophe. People know we are taking colossal risks, they want to do more and they want their governments to do more, polls say.
Tuesday's survey showed that people in developing nations were more likely to be willing to protect nature and the climate than those in richer countries.
Ninety-five percent of respondents in Indonesia, and 94 percent in South Africa, said they would do more for the planet, compared with just 70 percent and 74 percent in Germany and the United States, respectively.
New research has confirmed that renowned violin maker Antonio Stradivari and others treated their instruments with chemicals that produced their unique sound, and several of these chemicals have been identified for the first time.
Joseph Nagyvary, professor emeritus of biochemistry at Texas A&M, who first proposed the theory that chemicals used in making the violins—not so much the skill of making the instrument itself—was the reason Stradivari and others, such as Guarneri del Gesu, made instruments whosesoundhas not been equaled in over 200 years. An international team led by Hwan-Ching Tai, professor of chemistry at National Taiwan University, has had their findings published inAngewandte Chemie International Edition.
About 40 years ago at Texas A&M, Nagyvary was the first to prove a theory that he had spent years researching: that a primary reason for the pristine sound, beyond the fine craftsmanship, was the chemicals Stradivari and others used to treat their instruments due to a worm infestation at the time.
Their research over many years has been based on the assumption that the wood of the great masters underwent an aggressive chemical treatment, and this had a direct role in creating the great sound of the Stradivari and the Guarneri.
These findings were verified in a review by the American Chemical Society, the world's largest scientific organization.
The current findings of the research team show that borax, zinc, copper and alum—along with lime water—were used to treat the wood used in the instruments.
The presence of these chemicals all points to collaboration between the violin makers and the local drugstore and druggist at the time. Both Stradivari and Guarneri would have wanted to treat their violins to prevent worms from eating away the wood because worm infestations were very widespread at that time."
He said that each violin maker probably used his own home-grown methods when treating the wood.
"This new study reveals that Stradivari and Guarneri had their own individual proprietary method of wood processing, to which they could have attributed a considerable significance," he said. "They could have come to realize that the special salts they used for impregnation of the wood also imparted to it some beneficial mechanical strength and acoustical advantages. These methods were kept secret. There were no patents in those times. How the wood was manipulated with chemicals was impossible to guess by the visual inspection of the finished product.
He said that the varnish recipes were not secret because the varnish itself is not a critical determinant of tone quality. In contrast, the process of how the fresh spruce planks were treated and processed with a variety of water-based chemical treatments is critical for the sound of the finished violin.
Such knowledge was needed to gain a "competitive advantage" over other instrument makers.
Cheng‐Kuan Su et al, Materials Engineering of Violin Soundboards by Stradivari and Guarneri, Angewandte Chemie International Edition (2021). DOI: 10.1002/anie.202105252
A new study shows urbanization is causing many mammal species to grow bigger, possibly because of readily available food in places packed with people.
The finding runs counter to many scientists' hypothesis that cities would trigger mammals to get smaller over time. Buildings and roads trap and re-emit a greater degree of heat than green landscapes, causing cities to have higher temperatures than their surroundings, a phenomenon known as the urban heat island effect.. Animals in warmer climatestend to be smaller than the same species in colder environments, a classic biological principle called Bergmann's Rule.
But researchers discovered an unexpected pattern when they analyzed nearly 140,500 measurements of body length and mass from more than 100 North American mammalspecies collected over 80 years: City-dwelling mammals are both longer and heftier than their rural counterparts.
In theory, animalsin cities should be getting smaller because of these heat island effects, but the researchers didn't find evidence for this happening in mammals. This paper is a good argument for why we can't assume Bergmann's Rule or climate alone is important in determining the size of animals.
Maggie M. Hantak et al, Mammalian body size is determined by interactions between climate, urbanization, and ecological traits, Communications Biology (2021). DOI: 10.1038/s42003-021-02505-3
First steerable catheter developed for brain surgery
A team of engineers and physicians has developed a steerable catheter that for the first time will give neurosurgeons the ability to steer the device in any direction they want while navigating the brain's arteries and blood vessels. The device was inspired by nature, specifically insect legs and flagella—tail-like structures that allow microscopic organisms such as bacteria to swim.
The steerable catheter was successfully tested in pigs .
Rattlesnakes increase their rattling rate as potential threats approach, and this abrupt switch to a high-frequency mode makes listeners, including humans, think they're closer than they actually are, researchers report August 19th in the journal Current Biology.
The acoustic display of rattlesnakes, which has been interpreted for decades as a simple acoustic warning signal about the presence of the snake, is in fact a far more intricate interspecies communication signal. The sudden switch to the high-frequency mode acts as a smart signal fooling the listener about its actual distance to the sound source. The misinterpretation of distance by the listener thereby creates a distance safety margin.
Additional results showed that rattlesnakes adapt their rattling rate in response to the approach velocity of an object rather than its size.
Snakes do not just rattle to advertise their presence, but they evolved an innovative solution: a sonic distance warning device similar to the one included in cars while driving backwards.
Rattlesnakes vigorously shake their tails to warn other animals of their presence. Past studies have shown that rattling varies in frequency, but little is known about the behavioral relevance of this phenomenon or what message it sends to listeners. Researchers noticed that rattling increased in frequency when they approached rattlesnakes but decreased when they walked away.
Scientists harness human protein to deliver molecular medicines to cells
Researchers have developed a new way to deliver molecular therapies to cells. The system, called SEND, can be programmed to encapsulate and deliver different RNA cargoes. SEND harnesses natural proteins in the body that form virus-like particles and bind RNA, and it may provoke less of an immune response than other delivery approaches.
Segel M, Lash B, et al. Mammalian retrovirus-like protein PEG10 packages its own mRNA and can be pseudotyped for intercellular mRNA delivery. Science. Online August 19, 2021. DOI: 10.1126/science.abg6155
This exotic particle had an out-of-body experience; these scientists took a picture of it
Scientists have taken the clearest picture yet of electronic particles that make up a mysterious magnetic state called quantum spin liquid (QSL).
The achievement could facilitate the development of superfast quantum computers and energy-efficient superconductors.
The scientists are the first to capture an image of how electrons in a QSL decompose into spin-like particles called spinons and charge-like particles called chargons.
Researchers discover hidden SARS-CoV-2 'gate' that opens to allow COVID infection
Since the early days of the COVID pandemic, scientists have aggressively pursued the secrets of the mechanisms that allow severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to enter and infect healthy human cells.
Researchers have discovered how glycans—molecules that make up a sugary residue around the edges of the spike protein—act as infection gateways. They essentially figured out how the spike actually opens and infects. The research team's gate discovery opens potential avenues for new therapeutics to counter SARS-CoV-2 infection. If glycan gates could be pharmacologically locked in the closed position, then the virus is effectively prevented from opening to entry and infection.
We throw away a third of the food we grow – here’s what to do about waste
One-third of all food produced each year is squandered or spoiled before it can be consumed. Research also suggests that high-income countries waste as much food as sub-Saharan Africa produces.
This food waste then ends up in landfills to rot – which releases greenhouse gases. And when this is combined with the amount of energy it takes to produce, manufacture, transport and store this food, it contributes a staggering3 billion tonnesof carbon dioxide to our planet. To put that in context, if food waste was a country, it would be the third-highest emitter ofgreenhouse gasesin the world, after the US and China.
But the good news is there are numerous techniques, technologies and policies that together could help reduce global food waste at every point in the process of producing and consuming it.
According to theFood and Agriculture Organisationfor the United Nations, lack of infrastructure, limited knowledge on storage and food handling, combined with unfavourable climatic conditions, can lead to a lot of food spoilage and waste in low-income countries.
On the other hand, in high-income countries, aesthetic preferences and arbitrary sell-by dates mean food easily becomes waste. Cosmetic blemishes, produce that is too ripe, too big, too little or even the wrong shape can lead to perfectly good fruits and vegetables going to waste.
As the global population continues to increase, it places real pressure on world food production. So we must stop food wastage. what are the causes for food waste?
1.plant diseases and pests – along with poor harvesting techniques – can be a big factor in the high levels of food waste
artificial intelligence (AI) powered drones can help farmers become more resourceful and reduce the overuse of pesticides in food production. This is important because pesticides can adversely affect the food ecosystem.
A big part of the food waste problem is changing how we shop and view food and our mindset around what constitutes waste. But research shows the best way to tackle food waste among consumers is to highlight the potential money that can be saved as well as the “feel-good factor”, or moral value, of doing a good thing for the environment. knowledge on how to use leftovers to create new meals helps a lot.
A more creative approach to food waste comes via a circular food system, which prevents food waste from being discarded. It can, for example, be converted into renewable energy. Waste can even be transformed into more food for humans (for example, tofu from leftover soybeans), as well as animal feed.
Support businesses or restaurants that use waste foods in their products or meals. Planning your meals around sell-by dates. Not throwing out food if it’s a bit wilted or bruised and only buying what you need – especially on special occasions where food can often go uneaten and to waste.
You can also show supermarkets that “wonky” fruit and veggies are just as good as the “normal” shaped produce by buying these over the perfect looking pears or potatoes.
Ultimately, it’s not going to be any single thing that solves food waste, but a collective approach can enable us to make the changes that need to happen.
Experimental confirmation of wave-particle duality
The 21st century has undoubtedly been the era of quantum science. Quantum mechanics was born in the early 20th century and has been used to develop unprecedented technologies which include quantum information, quantum communication, quantum metrology, quantum imaging, and quantum sensing. However, in quantum science, there are still unresolved and even inapprehensible issues like wave-particle duality and complementarity, superposition of wave functions, wave function collapse after quantum measurement, wave function entanglement of the composite wave function, etc.
To test the fundamental principle ofwave-particle dualityand complementarity quantitatively, a quantum composite system that can be controlled by experimental parameters is needed. So far, there have been several theoretical proposals after Neils Bohr introduced the concept of "complementarity" in 1928, but only a few ideas have been tested experimentally, with them detecting interference patterns with low visibility. Thus, the concept of complementarity and wave-particle duality still remains elusive and has not been fully confirmed experimentally yet.
To address this issue, a research team from the Institute for Basic Science (IBS, South Korea) constructed a double-path interferometer consisting of two parametric downconversion crystals seeded by coherent idler fields. The device generates coherent signal photons (quantons) that are used for quantum interference measurement. The quantons then travel down two separate paths before reaching the detector. The conjugate idler fields are used for extracting path information with controllable fidelity, which is useful for quantitatively elucidating the complementarity.
Researchers at the Martin Luther University Halle-Wittenberg (MLU) in Germany and the Brazilian University of Pará have developed a climate-friendly alternative to conventional cement. Carbon dioxide (CO2) emissions can be reduced during production by up to two thirds when a previously unused overburden from bauxite mining is used as a raw material. The alternative was found to be just as stable as the traditional Portland cement. The results were published in Sustainable Materials and Technologies.
As women’s soccer, rugby and other sports gain popularity, scientists are racing to understand how the female brain responds to head injury.
A growing body of data suggests that female athletes are at significantly greater risk of a traumatic brain injury event than male athletes. They also fare worse after a concussion and take longer to recover. As researchers gather more data, the picture becomes steadily more alarming.
Researchers have offered some explanations for the greater risk to women, although the science is at an early stage. Their ideas range from differences in the microstructure of the brain to the influence of hormones, coaching regimes, players’ level of experience and the management of injuries.
Given that most, if not all, sports-concussion protocols are based on data from men, female athletes ranging from schoolgirls to this year’s Olympic football squads are being put at risk of serious injury. We take all of these data, primarily from studies on men; we apply them to women. That’s just got to change.
Coaching protocols at all levels are changing to try to prevent injury, but these have generally neglected to include a huge cohort: women.
Studies from US collegiate sports have shown that female athletes are 1.9 times more likely to develop a sports-related concussion than are their male contemporaries in comparable sports(1). Those female students also missed many more study days as they recovered.
It’s not just the number of head injuries that differs between women and men, but also their nature. A review of 25 studies of sport-related concussion suggests that female athletes are not only more susceptible to concussion than are males, but also sustain more-severe concussions (2)
Footnotes:
1. Bretzin, A. C. et al.Am. J. Sports Med.46, 2263–2269 (2018).
2. McGroarty, N. K., Brown, S. M. & Mulcahey, M. K. Orthop.J. Sports Med.8, 2325967120932306 (2020).
The damage that causes concussion can be quite subtle. The brain can’t move that much in the skull, explains Stewart. “The brain virtually fills the intercranial cavity, and there’s a little thin film of fluid that fills up what space is left.” But, in the split second after an impact, the head rapidly decelerates, and the resulting forces transmit deep inside the brain. The gelatinous grey matter undergoes significant shear forces when the head stops suddenly, pushing and pulling the brain tissue in a way that can cause structural damage.
And those forces can affect the brains of men and women in profoundly different ways.
Long COVID Might Be The Manifestation of a Different Virus Reawakened in The Body
People who struggle to recover fromCOVID-19could be battling more than justSARS-CoV-2. Their immune systems might also be involved with anothervirusas well.
New research suggests that's no coincidence. In some cases, both chronic illnesses might have similar roots. A recent study among 185 COVID-19 patients in the United States has found the majority of 'long haulers' the researchers tested were positive for Epstein-Barr virus (EBV) reactivation.
Recent research has found that a subset of CFS/ME patients show signs of EBV reactivation, and now, it seems that a potentially large percentage of people with long COVID do as well.
EBV is one of the most common viral infections out there. The vast majority of people around the world contract the virus at some point in their lives, and after the acute infection phase,an inactive versionof the virus sticks around in the body for a lifetime.
Gravity is the weird, mysterious glue that binds the Universe together, but that's not the limit of its charms. We can also leverage the way it warps space-time to see distant objects that would be otherwise much more difficult to make out.
This is called gravitational lensing, an effect predicted by Einstein, and it's beautifully illustrated in a new release from the Hubble Space Telescope.
In the center in the image (below) is a shiny, near-perfect ring with what appear to be four bright spots threaded along it, looping around two more points with a golden glow.
This is called an Einstein ring, and those bright dots are not six galaxies, but three: the two in the middle of the ring, and one quasar behind it, its light distorted and magnified as it passes through the gravitational field of the two foreground galaxies.
Because the mass of the two foreground galaxies is so high, this causes a gravitational curvature of space-time around the pair. Any light that then travels through this space-time follows this curvature and enters our telescopes smeared and distorted – but also magnified.
This, as it turns out, is a really useful tool for probing both the far and near reaches of the Universe. Anything with enough mass can act as a gravitational lens. That can mean one or two galaxies, as we see here, or even huge galaxy clusters, which produce awonderful messof smears of light from themany objects behind them.
Astronomers peering into deep space can reconstruct these smears and replicated images to see in much finer detail the distant galaxies thus lensed. But that's not all gravitational lensing can do. The strength of a lens depends on the curvature of the gravitational field, which is directly related to the mass it's curving around.
So gravitational lenses can allow us to weigh galaxies and galaxy clusters, which in turn can then help us find and map dark matter – the mysterious, invisible source of mass that generates additional gravity that can't be explained by the stuff in the Universe we can actually detect.
People with rare autoimmune diseases are at higher risk of death from Covid-19
New research has revealed that people with rare autoimmune rheumatic diseases are at an increased risk of developing Covid-19 and subsequently dying from it. Experts found that people with these conditions were 54% more likely to test positive for a Covid-19 infection, and death related to Covid-19 was 2.4 times more likely than for people in the general population when age and sex was taken into account. Researchers say there is an urgent need to understand the effectiveness of the vaccine among people with diseases such as vasculitis and lupus. The findings, published as a pre-print in medRxiv and currently under peer review, is the work of a team of doctors and researchers from RECORDER (Registration of Complex Rare Diseases Exemplars in Rheumatology), which is a joint project between the University of Nottingham, Nottingham University Hospitals NHS Trust and the National Disease Registration Service at Public Health England.
In this latest study, funded by the British Society for Rheumatology and Vasculitis UK, the team looked at nearly 170,000 people in England with rare autoimmune rheumatic diseases. Between March and July 2020, during the first wave of the Covid-19 pandemic in England, they found:
• 1,874 people (1.11%) had Covid-19 infection (PCR test positive)
• Taking age into account, the infection rate in people with rare autoimmune rheumatic diseases was 54% higher than in the general population
• 713 (0.42%) people living with rare autoimmune rheumatic disease died related to Covid-19 infection
• Covid-19 related death was 2.4 times more common in people with rare autoimmune rheumatic disease compared to the general population (taking age and sex into account)
These findings are particularly important as recently published data show that people who are immunosuppressed, which includes many people with rare autoimmune rheumatic diseases, can have lower levels of protection from Covid-19 vaccination due to a weaker immune response.
Gut bacteria and flavonoid-rich foods are linked and improve blood pressure levels
Flavonoid-rich foods, including berries, apples, pears and wine, appear to have a positive effect on blood pressure levels, an association that is partially explained by characteristics of the gut microbiome, according to new research published today in Hypertension, an American Heart Association journal.
Our gut microbiome plays a key role in metabolizing flavonoids to enhance their cardioprotective effects, and this study provides evidence to suggest these blood pressure-lowering effects are achievable with simple changes to the daily diet.
Flavonoids are compounds found naturally in fruits, vegetables and plant-based foods such as tea, chocolate and wine, and have been shown in previous research to offer a variety of health benefits to the body. Flavonoids are broken down by the body's gut microbiome—the bacteria found in the digestive tract. Recent studies found a link betweengut microbiota, the microorganisms in the human digestive tract, andcardiovascular disease(CVD), which is the leading cause of death worldwide. Gut microbiota is highly variable between individuals, and there are reported differences in gut microbial compositions among people with and without CVD.
With increased research suggesting flavonoids may reduce heart disease risk, this study assessed the role of the gut microbiome on the process. Researchers examined the association between eating flavonoid-rich foods with blood pressure and gut microbiome diversity. The study also investigated how much variance within the gut microbiome could explain the association between intake of flavonoid-rich foods and blood pressure.
Microbial Diversity and Abundance of Parabacteroides Mediate the Associations Between Higher Intake of Flavonoid-Rich Foods and Lower Blood Pressure, Hypertension (2021). www.ahajournals.org/doi/10.116 … TENSIONAHA.121.17441
The analysis of regular flavonoid intake with gut microbiome and blood pressure levels found:
Study participants who had the highest intake of flavonoid-rich foods, including berries, red wine, apples and pears, had lower systolic blood pressure levels, as well as greater diversity in their gut microbiome than the participants who consumed the lowest levels of flavonoid-rich foods.
Up to 15.2% of the association between flavonoid-rich foods and systolic blood pressure could be explained by the diversity found in participants' gut microbiome.
Eating 1.6 servings of berries per day (one serving equals 80 grams, or 1 cup) was associated with an average reduction in systolic blood pressure levels of 4.1 mm Hg, and about 12% of the association was explained by gut microbiome factors.
Drinking 2.8 glasses (125 ml of wine per glass) of red wine a week was associated with an average of 3.7 mm Hg lower systolicbloodpressure level, of which 15% could be explained by the gutmicrobiome.
High-efficiency ultraviolet light emitting diodes to sterilize pathogens, including SARS -CoV-2
Every year, thousands of lives and billions of dollars are spent worldwide as a result of health-care associated and waterborne illnesses. Sterilization is a critical preventative measure and it can be achieved by a number of techniques including irradiation using ultraviolet (UV) light. This need has gained greater urgency because of the global coronavirus pandemic, as effectivesterilizationpractices can curtail the spread of infectious diseases.
Current sources like mercury lamps are bulky, contain toxic chemicals and are not as versatile in applications as semiconductor light sources. AlGaN is the material of choice forhigh efficiencydeep UV light sources, which is the only alternative technology to replace mercury lamps for water purification and disinfection. To date, however, AlGaN-based mid and deep UV LEDs exhibit very low efficiency. One of the primary limiting factors is the poor hole injection, due to the ineffective p-type doping of AlGaN alloys using Mg, especially for the high Al composition alloys that are essential for the UV-C (200-280 nm) wavelength ranges.
A promising technique that can overcome this challenge and enhance hole injection into the device active region is by utilizing a tunnel junction structure. The hole injection in such devices is driven by the interband transport of electrons from the valence band of the p-type layer to the conduction band of the n-type layer.
A. Pandey et al, High-efficiency AlGaN/GaN/AlGaN tunnel junction ultraviolet light-emitting diodes, Photonics Research (2020). DOI: 10.1364/PRJ.383652
A. Pandey et al, High-efficiency AlGaN/GaN/AlGaN tunnel junction ultraviolet light-emitting diodes, Photonics Research (2020). DOI: 10.1364/PRJ.383652
One material with two functions could lead to faster memory
In a step toward a future of higher performance memory devices, researchers have developed a new device that needs only a single semiconductor known as perovskite to simultaneously store and visually transmit data.
By integrating a light-emitting electrochemical cell with a resistive random-access memory that are both based on perovskite, the team achieved parallel and synchronous reading of data both electrically and optically in a 'light-emitting memory.'
Meng-Cheng Yen et al, All-inorganic perovskite quantum dot light-emitting memories, Nature Communications (2021). DOI: 10.1038/s41467-021-24762-w
Study: Benefits outweigh risks for autonomous vehicles—as long as you regulate them
An interdisciplinary panel of experts has assessed the risks and potential benefits associated with deploying autonomous vehicles (AVs) on U.S. roads and predicts that the benefits will substantially outweigh potential harms—but only if the AVs are well regulated.
Veljko Dubljevic et al, Toward a rational and ethical sociotechnical system of autonomous vehicles: A novel application of multi-criteria decision analysis, PLOS ONE (2021). DOI: 10.1371/journal.pone.0256224
How the brain’s internal ‘hourglass’ controls our need for sleep
Although sleep is absolutely vital, until now it hasn’t been known which structure of the brain tells us when we are tired. But a recent study has shown in laboratory mice that the cerebral cortex, which is responsible for the most complex brain functions – including perception, language, thought and episodic memory – helps us track our need for sleep.
To ensure that we get enough sleep, our brain uses two tools: a clock and an hourglass. Our biological clock helps us to keep a 24-hour rhythm. It’s controlled by thesuprachiasmatic nucleus, which is a small area deep in our brain. This coordinates the rhythms of various organs, and helps us to sleep at night and wake up in the morning.
But our biological clock is only a guide – it’s not the main regulator of sleep. Instead, the brain uses an “hourglass” to keep track of the accumulated amount of sleep we’ve had. This hourglass slowly empties while we’re awake and refills while we’re asleep. This is why we’re able to stay awake longer when we need to, and make up this sleep deficit later by napping or sleeping longer the next night.
Some researchers have proposed that the brain does not measure the time we have spent awake – rather, it trackshow hard the brain works while we’re awake, and adjusts the amount of sleep we need accordingly. Research in support of this theory has found that individual areas ofcortex can briefly switch offwhen overworked, even while the rest of the brain is still awake. This temporary shutdown of individual brain areas is termed “local sleep” and thought to be a mechanism thatallows the brain’s cells to recover. While a person might not notice it, such a localised shutdown canprofoundly affect someone’s performance– for example while driving a car.
But our brain would be very inefficient if individual parts of the cortex often went into local sleep whenever they felt they needed to. This is why it’s thought that the cortex may not only generate local sleep, but also activate the main sleep centres.
. Suppressing sleep might be dangerous, as sleep serves several essential, but still poorly understood, functions in our body and brain – such as memory processing, and making sure our immune system and metabolism function properly. But for many of us who struggle to feel tired and fall asleep, manipulating the cortex could become a way of triggering sleep when we’re struggling to nod off.
Some Rare Diamonds Form Out of The Remains of Once-Living Creatures
New research has discovered that two different types of rare diamonds share a common origin story – the recycling of once-living organisms over 400 kilometers (250 miles) below the surface.
There are three main types of natural diamonds. The first are lithospheric diamonds, which form in the lithospheric layer around 150 to 250 kilometers (93 - 155 miles) below the surface of Earth. These are by far the most common.
Then there are two rarer types - oceanic and super-deep continental diamonds.
Oceanic diamonds are found in oceanic rocks, while deep continental diamonds are those formed between 300 and 1,000 kilometers (186 and 621 miles) below the surface of Earth.
oceanic and super-deep continental diamonds seem pretty different. Because variation in a carbon isotope signature called δ13C (delta carbon thirteen) can be used to determine whether the carbon has an organic or inorganic origin, past researchers have suggested that oceanic diamonds originally formed from organic carbon that was once within living beings.
Super-deep continental diamonds, on the other hand, have an extremely variable amount of δ13C. It's hard to tell whether they're made of organic carbon or not.
But in this new paper, led by Curtin University geologist Luc Doucet, the team found that the cores of super-deep continental diamonds have a similar δ13C composition. Surprisingly, this means that, like oceanic diamonds, these gems also contain the remains of once-living creatures.
A host enzyme allows viruses to ride roughshod in the liver, paving the way to cancer
Chronic viral infections in the liver can lead to organ dysfunction and ultimately to liver tumors in a progression invariably characterized by viruses that proliferate free of immune system restraints.
Although it has been known for decades that chronic viral infectionof the liver can lead to cancer, medical investigators have only now begun to fully appreciate how the disruption of molecular signaling sets the stage for virus-induced liver cancer.
In an elegant series of cellular studies, scientists have found that a transmembrane enzyme (a protein embedded in the cell with active portions above and below the cell surface) plays a powerful role in damaging liver cells.
That enzyme goes by the name of hepsin, and is produced by the host. It increases vulnerability to liver cancer because it's a noteworthy turncoat—a biological traitor—when active in the milieu of a viral infection. Although the research team saw the damaging activity in the lab when two types of viruses, Sendai and herpes, were studied, the major global health crisis involving liver infections and cancer are centered squarely on hepatitis B and C.
Hepsin, as it turns out, doesn't even mess with the viruses themselves to create havoc in the liver; it irrevocably damages a protective protein called STING. Once STING is crippled, viruses are free to run roughshod through the liver.
Fu Hsin et al, The transmembrane serine protease hepsin suppresses type I interferon induction by cleaving STING, Science Signaling (2021). DOI: 10.1126/scisignal.abb4752
Microbiome-based therapies: Genetically engineered good bacteria could aid in combating disease
Our bodies are home to several bacterial species that help us maintain our health and wellbeing. Thus, engineering these good bacteria to alter the activity of genes gone awry, either by turning them down or by activating them, is a promising approach to improve health and combat diseases.
n a study published in the journalNature Communications, researchers at Texas A&M University have developed a sophisticated, programmable gene silencing system that might have future therapeutic implications.
Using chemical triggers, the researchers showed that lab-engineered bacteriaEscherichia coli(E. coli) could be induced to make gene products to suppress certain traits inCaenorhabditis elegans(C. elegans), a roundworm that consumes this strain of bacteria as food. Similarly, the researchers noted that in the future, symbiotic bacteriawithin the human microbiomecould be engineered to sense, record and deliver therapeutics to improve health and wellbeing.
Here, researchers have used bacteria to tweak the gene expression in another organism, which is a proof of concept that bacteria living in symbiosis with humans could be engineered to modulate human physiology and treat disease.
Baizhen Gao et al, Programming gene expression in multicellular organisms for physiology modulation through engineered bacteria, Nature Communications (2021). DOI: 10.1038/s41467-021-22894-7
In addition to the genes that are tightly bundled up into chromosomes, bacteria and certain other microbes have other shorter, circular strands of DNA, called plasmids. Not only can plasmids replicate, they also have much fewer genes than their chromosomal counterparts. These properties make plasmids easier to manipulate with genetic tools. In particular, segments of DNA from other organisms, known as transgenes, can be inserted into bacterial plasmids.
Further, as plasmids replicate, multiple copies of the transgenes are produced. For example, if the human gene for making insulin is inserted into aplasmid, then as the bacteria replicate, more copies of the plasmids and consequently insulin genes are made. And so, when these genes are expressed, more insulin is produced. Alternately, plasmids can be extracted from the bacteria and used as vehicles to insert transgenes into the genome of other cells to alter traits in those cells.
The researchers noted that while these types of genetic manipulations have been routine in mammalian cells and other simple microbes, they have often been difficult to orchestrate in more complex, multicellular organisms. To overcome these hurdles, Sun and her team selected a bacteria-host pair that have a symbiotic relationship. In particular, they chose the soil-dwelling worm,C. elegans,that feeds onE. coli.
First, they inserted a transgene intoE. coli's plasmid that can interfere with a genetically engineered strain ofC. elegans,which has the ability to glow fluorescently green. Then, using a chemical, they induced the plasmid to express the green fluorescence-suppressing gene. Last, they fed the bacteria toC. elegansand found that only thoseC. elegansthat consumed theE. coliwith the transgene stopped glowing green.
In addition, Sun and her team programmedE. Colito produce gene products with different "AND" and "OR" logic gates. Put simply,gene productscould be selectively produced only by the combined action of two or moregenes, like the mathematical "AND" operation, or if any one gene was expressed, like the mathematical "OR" operation. Once again, using chemical triggers, the researchers initiated an "AND" or "OR" combination of gene expression in theE. Colineeded to silence twitching behavior inC. elegansafter the worms fed on the bacteria.
Sun said that their bacteria-based gene silencing system could be easily extended to other living systems for applications in pest control, plant growth promotion and veterinary disease diagnosis.
"Bacteria have a symbiotic relationship with many species, affecting their hosts' metabolism, immunity and behavior," said Sun. "Here, we have taken advantage of the symbiosis betweenbacteriaand a relatively complex organism to engineer a programmable genetic tool that can influence host physiology in a positive way."
High cholesterol fuels cancer by fostering resistance to a form of cell death
Chronically high cholesterol levels are known to be associated with increased risks of breast cancer and worse outcomes in most cancers, but the link has not been fully understood.
In a new study appearing online Aug. 24 in the journalNature Communications, a research team led by the Duke Cancer Institute has identified the mechanisms at work, describing how breast cancer cellsuse cholesterol to develop tolerance to stress, making them impervious to death as they migrate from the original tumor site.
Most cancer cellsdie as they try to metastasize—it's a very stressful process. The few that don't die have this ability to overcome the cell's stress-induced death mechanism. researchers now found that cholesterol was integral in fueling this ability.
In the current study using cancer cell linesand mouse models, the researchers found that migrating cancer cells gobble cholesterol in response to stress. Most die.
But in the what-doesn't-kill-you-makes-you-stronger motif, those that live emerge with a super-power that makes them able to withstand ferroptosis, a natural process in which cells succumb to stress. These stress-impervious cancer cells then proliferate and readily metastasize.
The process appears to be used not only by ER-negative breast cancer cells, but other types of tumors, including melanoma. And the mechanisms identified could be targeted by therapies.
Researchers led by Professor Caroline Dean have uncovered the genetic basis for variations in the vernalization response shown by plants growing in very different climates, linking epigenetic mechanisms with evolutionary change.
Several factors can affect the DNA left at a crime scene, such as environmental factors (e.g., heat, sunlight, moisture, bacteria, and mold). Therefore, not all DNA evidence will result in a usable DNA profile. Further, DNA testing cannot identify when the suspect was at the crime scene or for how long.
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Murderers desperate to get rid of evidence might want to consider using bleach to wash away stains. But not just any bleach will do. When old-school chlorine-based bleach is splashed all over blood-stained clothing, even if the clothes are washed ten times, DNA is still detected.
So for the criminal aspiring for perfection, here’s the secret you’ll need to know: It’s theoxygen-producing detergentsthat will get rid of any incriminating evidence for good.
Researchers at the University of Valencia tested oxygen bleach on blood-stained clothing for two hours and found that it destroys all DNA evidence. Forensic tests such as luminal tests rely on the ability of blood to uptake oxygen: A protein in the blood called hemoglobin (responsible for transporting oxygen throughout the body) reacts with hydrogen peroxide and gives a positive test result.
Chlorine-based detergents contaminate blood, but leave behind intact hemoglobin. However, detergents such as Reckitt Benckiser’sVanishproduce oxygen bubbles, which cause the blood to degrade and no longer uptake oxygen.
Hopefully, anyone actually contemplating cleaning up bloodstains isn’t reading this.
In forensic casework, DNA of suspects could be found frequently on clothes of drowned bodies after hours, sometimes days of exposure to water. ... All in all, the results demonstrate thatDNA could still be recovered from clothes exposed to waterfor more than 1 week.3
Dr. Krishna Kumari Challa
Why are bubbles round?
Bubbles occur when a thin film (for example, of soapy water) traps some gas (for example, air). The molecules in the film are attracted to each other, which not only holds the film together, but also makes it shrink to the smallest possible area.
The smallest area enclosing any given volume? A sphere. Therefore, the film will shrink to cover a sphere, and then can’t shrink any further because of the trapped air. Thus, bubbles end up as round.
https://www.sciencefocus.com/science/why-are-bubbles-round/?utm_sou...
Aug 17, 2021
Dr. Krishna Kumari Challa
Aug 17, 2021
Dr. Krishna Kumari Challa
Protein may protect against neurodegenerative diseases
Cells translate their genetic material at rapid rates with exquisite precision to reproduce, repair damage or even combat disease. But the process can deregulate and give rise to disease. Byproducts of errant processes can build up like gunk in the gears, especially around neurons, breaking down the repair mechanisms and causing further damage and even neurodegenerative disorders such as Alzheimer's disease.
Now, an international research team may have found that a protein implicated in tumour growth may be able to help regulate awry cellular translation and protect against neuronal decay. They published their results on July 13 in the Cell Reports.
"Researchers have begun to understand that age-related neurodegenerative diseases may be caused by slow but steady accumulation of toxic peptide products, which leads to death of neurons, such as beta-amyloid plaques causing Alzheimer's disease.
Repeat-associated non-AUG (RAN) translation is one of the mechanisms that generates such toxic products."
When replicating their genetic material, cells look for specifically ordered markers that signal the spot where they should start and end the copy to make a specific protein. The signal is typically "AUG," but RAN translation doesn't need this signal and can begin processing at other points. The problem is that RAN translation can end up copying bits of repeated genetic information that become the toxic buildup that leads to neurodegeneration.
In diseased conditions, 5MP is a protein that can potentially transform a healthy cell into a tumor cell. In healthy conditions, 5MP mimics a protein involved in regulating RAN translation. The researchers used electron microscopy and computer-directed modeling to reveal the structure of the preinitiation complex of molecules that assemble prior to RAN translation beginning. They found that 5MP competes with the protein it mimics in human cells and, when it wins, it reduces RAN translation and its toxic byproducts.
part 1
Aug 18, 2021
Dr. Krishna Kumari Challa
To better understand how this finding translates to disease outcomes, the researchers engineered flies with fragile X-associated tremor ataxia syndrome, a neurodegenerative disorder. They found that increasing the levels of 5MP in the affected flies repressed neuronal toxicity and enhanced their lifespan.
"Taken together, these data suggest that modulation of 5MP levels could be a viable therapeutic target by which to selectively reduce RAN translation in repeat expansion disorders
Chingakham Ranjit Singh et al, Human oncoprotein 5MP suppresses general and repeat-associated non-AUG translation via eIF3 by a common mechanism, Cell Reports (2021). DOI: 10.1016/j.celrep.2021.109376
part 2
https://medicalxpress.com/news/2021-08-protein-neurodegenerative-di...
Aug 18, 2021
Dr. Krishna Kumari Challa
Histamine could be a key player in depression, according to study in mice
Bodily inflammation dampens levels of a "feel-good molecule" and antidepressants' ability to boost them, according to new research in mice.
The findings, from researchers at Imperial College London and University of South Carolina, add to mounting evidence that inflammation, and the accompanying release of the molecule histamine, affects a key molecule responsible for mood in the brain—serotonin.
If replicated in humans, the findings—which identify histamine as a "new molecule of interest" in depression—could open new avenues for treating depression, which is the most common mental health problem worldwide.
Inflammation—a blanket term describing an immune response—triggers the release of histamine in the body. This increases blood flow to affected areas to flood them with immune cells. While these effects help the body fight infections, both long-term and acute inflammation is increasingly linked to depression.
Inflammation accompanies infections but can also be caused by stress, allergic responses and a host of chronic diseases such as diabetes, obesity, cancer and neurodegenerative diseases.
Melinda Hersey et al, Inflammation-Induced Histamine Impairs the Capacity of Escitalopram to Increase Hippocampal Extracellular Serotonin, The Journal of Neuroscience (2021). DOI: 10.1523/JNEUROSCI.2618-20.2021
https://medicalxpress.com/news/2021-08-histamine-key-player-depress...
Aug 18, 2021
Dr. Krishna Kumari Challa
Quantum entanglement is explained in classic terms
In many quantum measurement experiments and thought experiments, measurement results appear that do not seem to have classic explanations. As example: In quantum particle spin experiments, entangled particles appear to interact instantly across distances; and in interferometer experiments, one measurement result appears to be split over two paths. Currently, these measurement phenomena are treated as unique to quantum mechanics and not understandable in classic physics. Recognizing calibration in theory explains and resolves all the differences that appear to occur between classic and quantum measurements.
https://sciencex.com/news/2021-08-quantum-entanglement-classic-term...
More information: M. Born (editor), The Born-Einstein Letters, page 158, Macmillan, London, 1971. "Spooky action at a distance" is a phrase Einstein applied.
J. C. Maxwell, A Treatise on Electricity and Magnetism, 3rd Edition (1891), Dover Publications, New York, 1954, page 1.
L. Euler, Elements of Algebra, Chapter I, Article I, #3. Third edition, Longman, Hurst, Rees, Orme and Co., London England, 1822. Page 1: "Now, we cannot measure or determine one quantity, except by considering some other quantity of the same kind as known, and pointing out their mutual relation." www.google.com/books/edition/E … &printsec=frontcover
International Vocabulary of Metrology (VIM) 3rd edition, BIPM JCGM 200:2012, para. 2.39 calibration. www.bipm.org/en/publications/guides/vim.html
Measurement, Vol 182, September 2021 doi.org/10.1016/j.measurement.2021.109625
Aug 18, 2021
Dr. Krishna Kumari Challa
Wash your hands for 20 seconds: Physics shows why
Though hand-washing is proven effective in combating the spread of disease and infection, the physics behind it has rarely been studied. But in Physics of Fluids, researchers describe a simple model that captures the key mechanics of hand-washing.
By simulating hand-washing, they estimated the time scales on which particles, like viruses and bacteria, were removed from hands.
The mathematical model acts in two dimensions, with one wavy surface moving past another wavy surface, and a thin film of liquid between the two. Wavy surfaces represent hands because they are rough on small spatial scales.
Particles are trapped on the rough surfaces of the hand in potential wells. In other words, they are at the bottom of a valley, and in order for them to escape, the energy from the water flow must be high enough to get them up and out of the valley.
The strength of the flowing liquid depends on the speed of the moving hands. A stronger flow removes particles more easily.
Basically, the flow tells you about the forces on the particles. Then you can work out how the particles move and figure out if they get removed.
If you move your hands too gently, too slowly, relative to one another, the forces created by the flowing fluid are not big enough to overcome the force holding the particle down.
It takes about 20 seconds of vigorous movement to dislodge potential viruses and bacteria.
"Will we ever wash our hands of lubrication theory?" Physics of Fluids (2021). aip.scitation.org/doi/10.1063/5.0060307
https://phys.org/news/2021-08-seconds-physics.html?utm_source=nwlet...
Physics shows why 20 seconds is right for hand-washing
Aug 18, 2021
Dr. Krishna Kumari Challa
Majority of climate change news coverage now accurate: study
Two decades ago, print media frequently gave equal credence to both legitimate climate experts and outlier climate deniers. But researchers found in more recent years that the media around the globe actually got it right most of the time. However, facts now outweigh a debate.
Nine out of ten media stories accurately reported the science on human contributions to climate change. It's not portrayed as a two-sided debate anymore.
Lucy McAllister et al, Balance as bias, resolute on the retreat? Updates & analyses of newspaper coverage in the United States, United Kingdom, New Zealand, Australia and Canada over the past 15 years, Environmental Research Letters (2021). DOI: 10.1088/1748-9326/ac14eb
https://phys.org/news/2021-08-majority-climate-news-coverage-accura...
Aug 18, 2021
Dr. Krishna Kumari Challa
Three in four say climate 'tipping points' close
Some 73 percent of people now believe that Earth's climate is approaching abrupt and irreversible "tipping points" due to human activity, according to a global opinion poll released on17th August, 2021.
Scientists are increasingly concerned that some feedback loops in nature—such as irreversible melting of icesheets or permafrost—may be close to being triggered as mankind's mind-boggling carbon emissions show no signs of slowing, despite a pandemic.
The IPCC report warned that Earth is on course to be 1.5C hotter than pre-industrial times around 2030—a full decade earlier than it projected just three years ago.
Tuesday's survey, conducted by the Global Commons Alliance and Ipsos MORI, found four out of five respondents wanted to do more to protect the planet.
The world is not sleepwalking towards catastrophe. People know we are taking colossal risks, they want to do more and they want their governments to do more, polls say.
Tuesday's survey showed that people in developing nations were more likely to be willing to protect nature and the climate than those in richer countries.
Ninety-five percent of respondents in Indonesia, and 94 percent in South Africa, said they would do more for the planet, compared with just 70 percent and 74 percent in Germany and the United States, respectively.
https://www.ipsos.com/ipsos-mori/en-uk/global-commons-survey-attitu...
Aug 18, 2021
Dr. Krishna Kumari Challa
The secret of the Stradivari violin confirmed
New research has confirmed that renowned violin maker Antonio Stradivari and others treated their instruments with chemicals that produced their unique sound, and several of these chemicals have been identified for the first time.
Joseph Nagyvary, professor emeritus of biochemistry at Texas A&M, who first proposed the theory that chemicals used in making the violins—not so much the skill of making the instrument itself—was the reason Stradivari and others, such as Guarneri del Gesu, made instruments whose sound has not been equaled in over 200 years. An international team led by Hwan-Ching Tai, professor of chemistry at National Taiwan University, has had their findings published in Angewandte Chemie International Edition.
About 40 years ago at Texas A&M, Nagyvary was the first to prove a theory that he had spent years researching: that a primary reason for the pristine sound, beyond the fine craftsmanship, was the chemicals Stradivari and others used to treat their instruments due to a worm infestation at the time.
Their research over many years has been based on the assumption that the wood of the great masters underwent an aggressive chemical treatment, and this had a direct role in creating the great sound of the Stradivari and the Guarneri.
These findings were verified in a review by the American Chemical Society, the world's largest scientific organization.
The current findings of the research team show that borax, zinc, copper and alum—along with lime water—were used to treat the wood used in the instruments.
The presence of these chemicals all points to collaboration between the violin makers and the local drugstore and druggist at the time. Both Stradivari and Guarneri would have wanted to treat their violins to prevent worms from eating away the wood because worm infestations were very widespread at that time."
He said that each violin maker probably used his own home-grown methods when treating the wood.
"This new study reveals that Stradivari and Guarneri had their own individual proprietary method of wood processing, to which they could have attributed a considerable significance," he said. "They could have come to realize that the special salts they used for impregnation of the wood also imparted to it some beneficial mechanical strength and acoustical advantages. These methods were kept secret. There were no patents in those times. How the wood was manipulated with chemicals was impossible to guess by the visual inspection of the finished product.
He said that the varnish recipes were not secret because the varnish itself is not a critical determinant of tone quality. In contrast, the process of how the fresh spruce planks were treated and processed with a variety of water-based chemical treatments is critical for the sound of the finished violin.
Such knowledge was needed to gain a "competitive advantage" over other instrument makers.
Cheng‐Kuan Su et al, Materials Engineering of Violin Soundboards by Stradivari and Guarneri, Angewandte Chemie International Edition (2021). DOI: 10.1002/anie.202105252
https://phys.org/news/2021-08-secret-stradivari-violin.html?utm_sou...
Aug 18, 2021
Dr. Krishna Kumari Challa
Cities are making mammals bigger
A new study shows urbanization is causing many mammal species to grow bigger, possibly because of readily available food in places packed with people.
The finding runs counter to many scientists' hypothesis that cities would trigger mammals to get smaller over time. Buildings and roads trap and re-emit a greater degree of heat than green landscapes, causing cities to have higher temperatures than their surroundings, a phenomenon known as the urban heat island effect.. Animals in warmer climates tend to be smaller than the same species in colder environments, a classic biological principle called Bergmann's Rule.
But researchers discovered an unexpected pattern when they analyzed nearly 140,500 measurements of body length and mass from more than 100 North American mammal species collected over 80 years: City-dwelling mammals are both longer and heftier than their rural counterparts.
In theory, animals in cities should be getting smaller because of these heat island effects, but the researchers didn't find evidence for this happening in mammals. This paper is a good argument for why we can't assume Bergmann's Rule or climate alone is important in determining the size of animals.
Maggie M. Hantak et al, Mammalian body size is determined by interactions between climate, urbanization, and ecological traits, Communications Biology (2021). DOI: 10.1038/s42003-021-02505-3
https://phys.org/news/2021-08-cities-mammals-bigger.html?utm_source...
Aug 18, 2021
Dr. Krishna Kumari Challa
Preserve a Strawberry Forever?
Aug 18, 2021
Dr. Krishna Kumari Challa
First steerable catheter developed for brain surgery
A team of engineers and physicians has developed a steerable catheter that for the first time will give neurosurgeons the ability to steer the device in any direction they want while navigating the brain's arteries and blood vessels. The device was inspired by nature, specifically insect legs and flagella—tail-like structures that allow microscopic organisms such as bacteria to swim.
The steerable catheter was successfully tested in pigs .
Tilvawala Gopesh et al, Soft robotic steerable microcatheter for the endovascular treatment of cerebral disorders, Science Robotics (2021). DOI: 10.1126/scirobotics.abf0601https://techxplore.com/news/2021-08...
Aug 20, 2021
Dr. Krishna Kumari Challa
Rattlesnake rattles trick human ears
Rattlesnakes increase their rattling rate as potential threats approach, and this abrupt switch to a high-frequency mode makes listeners, including humans, think they're closer than they actually are, researchers report August 19th in the journal Current Biology.
The acoustic display of rattlesnakes, which has been interpreted for decades as a simple acoustic warning signal about the presence of the snake, is in fact a far more intricate interspecies communication signal. The sudden switch to the high-frequency mode acts as a smart signal fooling the listener about its actual distance to the sound source. The misinterpretation of distance by the listener thereby creates a distance safety margin.
Additional results showed that rattlesnakes adapt their rattling rate in response to the approach velocity of an object rather than its size.
Snakes do not just rattle to advertise their presence, but they evolved an innovative solution: a sonic distance warning device similar to the one included in cars while driving backwards.
Current Biology, Forsthofer and Schutte et al.: "Frequency modulation of rattlesnake acoustic display affects acoustic distance perception in humans" www.cell.com/current-biology/f … 0960-9822(21)00973-8 , DOI: 10.1016/j.cub.2021.07.018
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Rattlesnakes vigorously shake their tails to warn other animals of their presence. Past studies have shown that rattling varies in frequency, but little is known about the behavioral relevance of this phenomenon or what message it sends to listeners. Researchers noticed that rattling increased in frequency when they approached rattlesnakes but decreased when they walked away.
https://phys.org/news/2021-08-rattlesnake-rattles-human-ears.html?u...
Aug 20, 2021
Dr. Krishna Kumari Challa
Scientists harness human protein to deliver molecular medicines to cells
Researchers have developed a new way to deliver molecular therapies to cells. The system, called SEND, can be programmed to encapsulate and deliver different RNA cargoes. SEND harnesses natural proteins in the body that form virus-like particles and bind RNA, and it may provoke less of an immune response than other delivery approaches.
Segel M, Lash B, et al. Mammalian retrovirus-like protein PEG10 packages its own mRNA and can be pseudotyped for intercellular mRNA delivery. Science. Online August 19, 2021. DOI: 10.1126/science.abg6155
https://medicalxpress.com/news/2021-08-scientists-harness-human-pro...
Aug 20, 2021
Dr. Krishna Kumari Challa
This exotic particle had an out-of-body experience; these scientists took a picture of it
Scientists have taken the clearest picture yet of electronic particles that make up a mysterious magnetic state called quantum spin liquid (QSL).
The achievement could facilitate the development of superfast quantum computers and energy-efficient superconductors.
The scientists are the first to capture an image of how electrons in a QSL decompose into spin-like particles called spinons and charge-like particles called chargons.
Ruan, W., Chen, Y., Tang, S. et al. Evidence for quantum spin liquid behaviour in single-layer 1T-TaSe2 from scanning tunnelling microscopy. Nat. Phys. (2021). doi.org/10.1038/s41567-021-01321-0 , www.nature.com/articles/s41567-021-01321-0
https://phys.org/news/2021-08-exotic-particle-out-of-body-scientist...
Aug 20, 2021
Dr. Krishna Kumari Challa
Researchers discover hidden SARS-CoV-2 'gate' that opens to allow COVID infection
Since the early days of the COVID pandemic, scientists have aggressively pursued the secrets of the mechanisms that allow severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to enter and infect healthy human cells.
Researchers have discovered how glycans—molecules that make up a sugary residue around the edges of the spike protein—act as infection gateways. They essentially figured out how the spike actually opens and infects. The research team's gate discovery opens potential avenues for new therapeutics to counter SARS-CoV-2 infection. If glycan gates could be pharmacologically locked in the closed position, then the virus is effectively prevented from opening to entry and infection.
A glycan gate controls opening of the SARS-CoV-2 spike protein, Nature Chemistry (2021). DOI: 10.1038/s41557-021-00758-3 , www.nature.com/articles/s41557-021-00758-3
https://phys.org/news/2021-08-hidden-sars-cov-gate-covid-infection....
Aug 20, 2021
Dr. Krishna Kumari Challa
We throw away a third of the food we grow – here’s what to do about waste
One-third of all food produced each year is squandered or spoiled before it can be consumed. Research also suggests that high-income countries waste as much food as sub-Saharan Africa produces.
This food waste then ends up in landfills to rot – which releases greenhouse gases. And when this is combined with the amount of energy it takes to produce, manufacture, transport and store this food, it contributes a staggering 3 billion tonnes of carbon dioxide to our planet. To put that in context, if food waste was a country, it would be the third-highest emitter of greenhouse gases in the world, after the US and China.
But the good news is there are numerous techniques, technologies and policies that together could help reduce global food waste at every point in the process of producing and consuming it.
According to the Food and Agriculture Organisation for the United Nations, lack of infrastructure, limited knowledge on storage and food handling, combined with unfavourable climatic conditions, can lead to a lot of food spoilage and waste in low-income countries.
On the other hand, in high-income countries, aesthetic preferences and arbitrary sell-by dates mean food easily becomes waste. Cosmetic blemishes, produce that is too ripe, too big, too little or even the wrong shape can lead to perfectly good fruits and vegetables going to waste.
As the global population continues to increase, it places real pressure on world food production. So we must stop food wastage. what are the causes for food waste?
1.plant diseases and pests – along with poor harvesting techniques – can be a big factor in the high levels of food waste
artificial intelligence (AI) powered drones can help farmers become more resourceful and reduce the overuse of pesticides in food production. This is important because pesticides can adversely affect the food ecosystem.
part1
Aug 20, 2021
Dr. Krishna Kumari Challa
A big part of the food waste problem is changing how we shop and view food and our mindset around what constitutes waste. But research shows the best way to tackle food waste among consumers is to highlight the potential money that can be saved as well as the “feel-good factor”, or moral value, of doing a good thing for the environment. knowledge on how to use leftovers to create new meals helps a lot.
A more creative approach to food waste comes via a circular food system, which prevents food waste from being discarded. It can, for example, be converted into renewable energy. Waste can even be transformed into more food for humans (for example, tofu from leftover soybeans), as well as animal feed.
Support businesses or restaurants that use waste foods in their products or meals. Planning your meals around sell-by dates. Not throwing out food if it’s a bit wilted or bruised and only buying what you need – especially on special occasions where food can often go uneaten and to waste.
You can also show supermarkets that “wonky” fruit and veggies are just as good as the “normal” shaped produce by buying these over the perfect looking pears or potatoes.
Ultimately, it’s not going to be any single thing that solves food waste, but a collective approach can enable us to make the changes that need to happen.
https://theconversation.com/we-throw-away-a-third-of-the-food-we-gr...
part2
Aug 20, 2021
Dr. Krishna Kumari Challa
Experimental confirmation of wave-particle duality
The 21st century has undoubtedly been the era of quantum science. Quantum mechanics was born in the early 20th century and has been used to develop unprecedented technologies which include quantum information, quantum communication, quantum metrology, quantum imaging, and quantum sensing. However, in quantum science, there are still unresolved and even inapprehensible issues like wave-particle duality and complementarity, superposition of wave functions, wave function collapse after quantum measurement, wave function entanglement of the composite wave function, etc.
To test the fundamental principle of wave-particle duality and complementarity quantitatively, a quantum composite system that can be controlled by experimental parameters is needed. So far, there have been several theoretical proposals after Neils Bohr introduced the concept of "complementarity" in 1928, but only a few ideas have been tested experimentally, with them detecting interference patterns with low visibility. Thus, the concept of complementarity and wave-particle duality still remains elusive and has not been fully confirmed experimentally yet.
To address this issue, a research team from the Institute for Basic Science (IBS, South Korea) constructed a double-path interferometer consisting of two parametric downconversion crystals seeded by coherent idler fields. The device generates coherent signal photons (quantons) that are used for quantum interference measurement. The quantons then travel down two separate paths before reaching the detector. The conjugate idler fields are used for extracting path information with controllable fidelity, which is useful for quantitatively elucidating the complementarity.
Quantitative Complementarity of Wave-Particle Duality, Science Advances (2021). DOI: 10.1126/sciadv.abi9268
https://phys.org/news/2021-08-experimental-wave-particle-duality.ht...
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Aug 20, 2021
Dr. Krishna Kumari Challa
Alternative cement with low carbon footprint developed
Researchers at the Martin Luther University Halle-Wittenberg (MLU) in Germany and the Brazilian University of Pará have developed a climate-friendly alternative to conventional cement. Carbon dioxide (CO2) emissions can be reduced during production by up to two thirds when a previously unused overburden from bauxite mining is used as a raw material. The alternative was found to be just as stable as the traditional Portland cement. The results were published in Sustainable Materials and Technologies.
Aug 20, 2021
Dr. Krishna Kumari Challa
Why sports concussions are worse for women
Researchers have offered some explanations for the greater risk to women, although the science is at an early stage. Their ideas range from differences in the microstructure of the brain to the influence of hormones, coaching regimes, players’ level of experience and the management of injuries.
Given that most, if not all, sports-concussion protocols are based on data from men, female athletes ranging from schoolgirls to this year’s Olympic football squads are being put at risk of serious injury. We take all of these data, primarily from studies on men; we apply them to women. That’s just got to change.
Coaching protocols at all levels are changing to try to prevent injury, but these have generally neglected to include a huge cohort: women.
Studies from US collegiate sports have shown that female athletes are 1.9 times more likely to develop a sports-related concussion than are their male contemporaries in comparable sports(1). Those female students also missed many more study days as they recovered.
It’s not just the number of head injuries that differs between women and men, but also their nature. A review of 25 studies of sport-related concussion suggests that female athletes are not only more susceptible to concussion than are males, but also sustain more-severe concussions (2)
Footnotes:
1. Bretzin, A. C. et al. Am. J. Sports Med. 46, 2263–2269 (2018).
2. McGroarty, N. K., Brown, S. M. & Mulcahey, M. K. Orthop. J. Sports Med. 8, 2325967120932306 (2020).
Aug 20, 2021
Dr. Krishna Kumari Challa
The damage that causes concussion can be quite subtle. The brain can’t move that much in the skull, explains Stewart. “The brain virtually fills the intercranial cavity, and there’s a little thin film of fluid that fills up what space is left.” But, in the split second after an impact, the head rapidly decelerates, and the resulting forces transmit deep inside the brain. The gelatinous grey matter undergoes significant shear forces when the head stops suddenly, pushing and pulling the brain tissue in a way that can cause structural damage.
And those forces can affect the brains of men and women in profoundly different ways.
https://www.nature.com/articles/d41586-021-02089-2?utm_source=Natur...
Part 2
Aug 20, 2021
Dr. Krishna Kumari Challa
Long COVID Might Be The Manifestation of a Different Virus Reawakened in The Body
People who struggle to recover from COVID-19 could be battling more than just SARS-CoV-2. Their immune systems might also be involved with another virus as well.
Ever since patients first started reporting long hauls of COVID-19, many of their lingering symptoms, such as fatigue and brain fog, have been compared to chronic fatigue syndrome or myalgic encephalomyelitis (CFS/ME).
New research suggests that's no coincidence. In some cases, both chronic illnesses might have similar roots. A recent study among 185 COVID-19 patients in the United States has found the majority of 'long haulers' the researchers tested were positive for Epstein-Barr virus (EBV) reactivation.
Recent research has found that a subset of CFS/ME patients show signs of EBV reactivation, and now, it seems that a potentially large percentage of people with long COVID do as well.
EBV is one of the most common viral infections out there. The vast majority of people around the world contract the virus at some point in their lives, and after the acute infection phase, an inactive version of the virus sticks around in the body for a lifetime.
Sometimes, EBV can reactivate and cause flu-like symptoms, such as during periods of psychological or physiological stress.
Like a global pandemic.
https://www.mdpi.com/2076-0817/10/6/763
https://www.sciencealert.com/mounting-evidence-suggests-many-covid-...
Aug 20, 2021
Dr. Krishna Kumari Challa
Scientists then and now
Aug 20, 2021
Dr. Krishna Kumari Challa
How Science Affects Your Ice Cream
Aug 21, 2021
Dr. Krishna Kumari Challa
There's science inside your ice cream, and it tastes delicious
Aug 21, 2021
Dr. Krishna Kumari Challa
Swimming robot gives fresh insight into locomotion and neuroscience
Aug 21, 2021
Dr. Krishna Kumari Challa
Aug 22, 2021
Dr. Krishna Kumari Challa
Hubble Captures a Stunning 'Einstein Ring'
Gravity is the weird, mysterious glue that binds the Universe together, but that's not the limit of its charms. We can also leverage the way it warps space-time to see distant objects that would be otherwise much more difficult to make out.
This is called gravitational lensing, an effect predicted by Einstein, and it's beautifully illustrated in a new release from the Hubble Space Telescope.
In the center in the image (below) is a shiny, near-perfect ring with what appear to be four bright spots threaded along it, looping around two more points with a golden glow.
This is called an Einstein ring, and those bright dots are not six galaxies, but three: the two in the middle of the ring, and one quasar behind it, its light distorted and magnified as it passes through the gravitational field of the two foreground galaxies.
Because the mass of the two foreground galaxies is so high, this causes a gravitational curvature of space-time around the pair. Any light that then travels through this space-time follows this curvature and enters our telescopes smeared and distorted – but also magnified.
This, as it turns out, is a really useful tool for probing both the far and near reaches of the Universe. Anything with enough mass can act as a gravitational lens. That can mean one or two galaxies, as we see here, or even huge galaxy clusters, which produce a wonderful mess of smears of light from the many objects behind them.
Astronomers peering into deep space can reconstruct these smears and replicated images to see in much finer detail the distant galaxies thus lensed. But that's not all gravitational lensing can do. The strength of a lens depends on the curvature of the gravitational field, which is directly related to the mass it's curving around.
So gravitational lenses can allow us to weigh galaxies and galaxy clusters, which in turn can then help us find and map dark matter – the mysterious, invisible source of mass that generates additional gravity that can't be explained by the stuff in the Universe we can actually detect.
https://esahubble.org/images/potw2132a/
Aug 22, 2021
Dr. Krishna Kumari Challa
People with rare autoimmune diseases are at higher risk of death from Covid-19
New research has revealed that people with rare autoimmune rheumatic diseases are at an increased risk of developing Covid-19 and subsequently dying from it. Experts found that people with these conditions were 54% more likely to test positive for a Covid-19 infection, and death related to Covid-19 was 2.4 times more likely than for people in the general population when age and sex was taken into account. Researchers say there is an urgent need to understand the effectiveness of the vaccine among people with diseases such as vasculitis and lupus. The findings, published as a pre-print in medRxiv and currently under peer review, is the work of a team of doctors and researchers from RECORDER (Registration of Complex Rare Diseases Exemplars in Rheumatology), which is a joint project between the University of Nottingham, Nottingham University Hospitals NHS Trust and the National Disease Registration Service at Public Health England.
In this latest study, funded by the British Society for Rheumatology and Vasculitis UK, the team looked at nearly 170,000 people in England with rare autoimmune rheumatic diseases. Between March and July 2020, during the first wave of the Covid-19 pandemic in England, they found:
• 1,874 people (1.11%) had Covid-19 infection (PCR test positive)
• Taking age into account, the infection rate in people with rare autoimmune rheumatic diseases was 54% higher than in the general population
• 713 (0.42%) people living with rare autoimmune rheumatic disease died related to Covid-19 infection
• Covid-19 related death was 2.4 times more common in people with rare autoimmune rheumatic disease compared to the general population (taking age and sex into account)
These findings are particularly important as recently published data show that people who are immunosuppressed, which includes many people with rare autoimmune rheumatic diseases, can have lower levels of protection from Covid-19 vaccination due to a weaker immune response.
https://www.nottingham.ac.uk/news/rare-autoimmune-diseases-and-covi...
Aug 22, 2021
Dr. Krishna Kumari Challa
'Missing jigsaw piece’: engineers make critical advance in quantum computer design
Aug 22, 2021
Dr. Krishna Kumari Challa
Food allergy and intolerance: the differences
Aug 23, 2021
Dr. Krishna Kumari Challa
Gut bacteria and flavonoid-rich foods are linked and improve blood pressure levels
Flavonoid-rich foods, including berries, apples, pears and wine, appear to have a positive effect on blood pressure levels, an association that is partially explained by characteristics of the gut microbiome, according to new research published today in Hypertension, an American Heart Association journal.
Our gut microbiome plays a key role in metabolizing flavonoids to enhance their cardioprotective effects, and this study provides evidence to suggest these blood pressure-lowering effects are achievable with simple changes to the daily diet.
Flavonoids are compounds found naturally in fruits, vegetables and plant-based foods such as tea, chocolate and wine, and have been shown in previous research to offer a variety of health benefits to the body. Flavonoids are broken down by the body's gut microbiome—the bacteria found in the digestive tract. Recent studies found a link between gut microbiota, the microorganisms in the human digestive tract, and cardiovascular disease (CVD), which is the leading cause of death worldwide. Gut microbiota is highly variable between individuals, and there are reported differences in gut microbial compositions among people with and without CVD.
With increased research suggesting flavonoids may reduce heart disease risk, this study assessed the role of the gut microbiome on the process. Researchers examined the association between eating flavonoid-rich foods with blood pressure and gut microbiome diversity. The study also investigated how much variance within the gut microbiome could explain the association between intake of flavonoid-rich foods and blood pressure.
Microbial Diversity and Abundance of Parabacteroides Mediate the Associations Between Higher Intake of Flavonoid-Rich Foods and Lower Blood Pressure, Hypertension (2021). www.ahajournals.org/doi/10.116 … TENSIONAHA.121.17441
part 1
Aug 24, 2021
Dr. Krishna Kumari Challa
The analysis of regular flavonoid intake with gut microbiome and blood pressure levels found:
https://medicalxpress.com/news/2021-08-gut-bacteria-flavonoid-rich-...
part 2
Aug 24, 2021
Dr. Krishna Kumari Challa
High-efficiency ultraviolet light emitting diodes to sterilize pathogens, including SARS -CoV-2
Every year, thousands of lives and billions of dollars are spent worldwide as a result of health-care associated and waterborne illnesses. Sterilization is a critical preventative measure and it can be achieved by a number of techniques including irradiation using ultraviolet (UV) light. This need has gained greater urgency because of the global coronavirus pandemic, as effective sterilization practices can curtail the spread of infectious diseases.
Current sources like mercury lamps are bulky, contain toxic chemicals and are not as versatile in applications as semiconductor light sources. AlGaN is the material of choice for high efficiency deep UV light sources, which is the only alternative technology to replace mercury lamps for water purification and disinfection. To date, however, AlGaN-based mid and deep UV LEDs exhibit very low efficiency. One of the primary limiting factors is the poor hole injection, due to the ineffective p-type doping of AlGaN alloys using Mg, especially for the high Al composition alloys that are essential for the UV-C (200-280 nm) wavelength ranges.
Aug 24, 2021
Dr. Krishna Kumari Challa
One material with two functions could lead to faster memory
In a step toward a future of higher performance memory devices, researchers have developed a new device that needs only a single semiconductor known as perovskite to simultaneously store and visually transmit data.
By integrating a light-emitting electrochemical cell with a resistive random-access memory that are both based on perovskite, the team achieved parallel and synchronous reading of data both electrically and optically in a 'light-emitting memory.'
Meng-Cheng Yen et al, All-inorganic perovskite quantum dot light-emitting memories, Nature Communications (2021). DOI: 10.1038/s41467-021-24762-w
https://techxplore.com/news/2021-08-material-functions-faster-memor...
Aug 24, 2021
Dr. Krishna Kumari Challa
Study: Benefits outweigh risks for autonomous vehicles—as long as you regulate them
An interdisciplinary panel of experts has assessed the risks and potential benefits associated with deploying autonomous vehicles (AVs) on U.S. roads and predicts that the benefits will substantially outweigh potential harms—but only if the AVs are well regulated.
Veljko Dubljevic et al, Toward a rational and ethical sociotechnical system of autonomous vehicles: A novel application of multi-criteria decision analysis, PLOS ONE (2021). DOI: 10.1371/journal.pone.0256224
https://techxplore.com/news/2021-08-benefits-outweigh-autonomous-ve...
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Aug 24, 2021
Dr. Krishna Kumari Challa
First video evidence of tortoises hunting birds / Curr. Biol., Aug. 23, 2021 (Vol. 31, Issue 16)
Aug 24, 2021
Dr. Krishna Kumari Challa
How the brain’s internal ‘hourglass’ controls our need for sleep
Although sleep is absolutely vital, until now it hasn’t been known which structure of the brain tells us when we are tired. But a recent study has shown in laboratory mice that the cerebral cortex, which is responsible for the most complex brain functions – including perception, language, thought and episodic memory – helps us track our need for sleep.
To ensure that we get enough sleep, our brain uses two tools: a clock and an hourglass. Our biological clock helps us to keep a 24-hour rhythm. It’s controlled by the suprachiasmatic nucleus, which is a small area deep in our brain. This coordinates the rhythms of various organs, and helps us to sleep at night and wake up in the morning.
But our biological clock is only a guide – it’s not the main regulator of sleep. Instead, the brain uses an “hourglass” to keep track of the accumulated amount of sleep we’ve had. This hourglass slowly empties while we’re awake and refills while we’re asleep. This is why we’re able to stay awake longer when we need to, and make up this sleep deficit later by napping or sleeping longer the next night.
part 1
Aug 24, 2021
Dr. Krishna Kumari Challa
Some researchers have proposed that the brain does not measure the time we have spent awake – rather, it tracks how hard the brain works while we’re awake, and adjusts the amount of sleep we need accordingly. Research in support of this theory has found that individual areas of cortex can briefly switch off when overworked, even while the rest of the brain is still awake. This temporary shutdown of individual brain areas is termed “local sleep” and thought to be a mechanism that allows the brain’s cells to recover. While a person might not notice it, such a localised shutdown can profoundly affect someone’s performance – for example while driving a car.
But our brain would be very inefficient if individual parts of the cortex often went into local sleep whenever they felt they needed to. This is why it’s thought that the cortex may not only generate local sleep, but also activate the main sleep centres.
. Suppressing sleep might be dangerous, as sleep serves several essential, but still poorly understood, functions in our body and brain – such as memory processing, and making sure our immune system and metabolism function properly. But for many of us who struggle to feel tired and fall asleep, manipulating the cortex could become a way of triggering sleep when we’re struggling to nod off.
https://theconversation.com/feeling-tired-heres-how-the-brains-inte...
part 2
Aug 24, 2021
Dr. Krishna Kumari Challa
Some Rare Diamonds Form Out of The Remains of Once-Living Creatures
New research has discovered that two different types of rare diamonds share a common origin story – the recycling of once-living organisms over 400 kilometers (250 miles) below the surface.
There are three main types of natural diamonds. The first are lithospheric diamonds, which form in the lithospheric layer around 150 to 250 kilometers (93 - 155 miles) below the surface of Earth. These are by far the most common.
Then there are two rarer types - oceanic and super-deep continental diamonds.
Oceanic diamonds are found in oceanic rocks, while deep continental diamonds are those formed between 300 and 1,000 kilometers (186 and 621 miles) below the surface of Earth.
oceanic and super-deep continental diamonds seem pretty different. Because variation in a carbon isotope signature called δ13C (delta carbon thirteen) can be used to determine whether the carbon has an organic or inorganic origin, past researchers have suggested that oceanic diamonds originally formed from organic carbon that was once within living beings.
Super-deep continental diamonds, on the other hand, have an extremely variable amount of δ13C. It's hard to tell whether they're made of organic carbon or not.
But in this new paper, led by Curtin University geologist Luc Doucet, the team found that the cores of super-deep continental diamonds have a similar δ13C composition. Surprisingly, this means that, like oceanic diamonds, these gems also contain the remains of once-living creatures.
https://www.nature.com/articles/s41598-021-96286-8
https://www.sciencealert.com/rare-diamonds-are-actually-made-of-onc...
Aug 24, 2021
Dr. Krishna Kumari Challa
A host enzyme allows viruses to ride roughshod in the liver, paving the way to cancer
Chronic viral infections in the liver can lead to organ dysfunction and ultimately to liver tumors in a progression invariably characterized by viruses that proliferate free of immune system restraints.
Although it has been known for decades that chronic viral infection of the liver can lead to cancer, medical investigators have only now begun to fully appreciate how the disruption of molecular signaling sets the stage for virus-induced liver cancer.
In an elegant series of cellular studies, scientists have found that a transmembrane enzyme (a protein embedded in the cell with active portions above and below the cell surface) plays a powerful role in damaging liver cells.
That enzyme goes by the name of hepsin, and is produced by the host. It increases vulnerability to liver cancer because it's a noteworthy turncoat—a biological traitor—when active in the milieu of a viral infection. Although the research team saw the damaging activity in the lab when two types of viruses, Sendai and herpes, were studied, the major global health crisis involving liver infections and cancer are centered squarely on hepatitis B and C.
Hepsin, as it turns out, doesn't even mess with the viruses themselves to create havoc in the liver; it irrevocably damages a protective protein called STING. Once STING is crippled, viruses are free to run roughshod through the liver.
Fu Hsin et al, The transmembrane serine protease hepsin suppresses type I interferon induction by cleaving STING, Science Signaling (2021). DOI: 10.1126/scisignal.abb4752
https://medicalxpress.com/news/2021-08-turncoat-protein-viruses-rou...
Aug 25, 2021
Dr. Krishna Kumari Challa
Microbiome-based therapies: Genetically engineered good bacteria could aid in combating disease
Our bodies are home to several bacterial species that help us maintain our health and wellbeing. Thus, engineering these good bacteria to alter the activity of genes gone awry, either by turning them down or by activating them, is a promising approach to improve health and combat diseases.
n a study published in the journal Nature Communications, researchers at Texas A&M University have developed a sophisticated, programmable gene silencing system that might have future therapeutic implications.
Using chemical triggers, the researchers showed that lab-engineered bacteria Escherichia coli (E. coli) could be induced to make gene products to suppress certain traits in Caenorhabditis elegans (C. elegans), a roundworm that consumes this strain of bacteria as food. Similarly, the researchers noted that in the future, symbiotic bacteria within the human microbiome could be engineered to sense, record and deliver therapeutics to improve health and wellbeing.
Here, researchers have used bacteria to tweak the gene expression in another organism, which is a proof of concept that bacteria living in symbiosis with humans could be engineered to modulate human physiology and treat disease.
Baizhen Gao et al, Programming gene expression in multicellular organisms for physiology modulation through engineered bacteria, Nature Communications (2021). DOI: 10.1038/s41467-021-22894-7
Part 1
Aug 25, 2021
Dr. Krishna Kumari Challa
In addition to the genes that are tightly bundled up into chromosomes, bacteria and certain other microbes have other shorter, circular strands of DNA, called plasmids. Not only can plasmids replicate, they also have much fewer genes than their chromosomal counterparts. These properties make plasmids easier to manipulate with genetic tools. In particular, segments of DNA from other organisms, known as transgenes, can be inserted into bacterial plasmids.
Further, as plasmids replicate, multiple copies of the transgenes are produced. For example, if the human gene for making insulin is inserted into a plasmid, then as the bacteria replicate, more copies of the plasmids and consequently insulin genes are made. And so, when these genes are expressed, more insulin is produced. Alternately, plasmids can be extracted from the bacteria and used as vehicles to insert transgenes into the genome of other cells to alter traits in those cells.
The researchers noted that while these types of genetic manipulations have been routine in mammalian cells and other simple microbes, they have often been difficult to orchestrate in more complex, multicellular organisms. To overcome these hurdles, Sun and her team selected a bacteria-host pair that have a symbiotic relationship. In particular, they chose the soil-dwelling worm, C. elegans, that feeds on E. coli.
First, they inserted a transgene into E. coli's plasmid that can interfere with a genetically engineered strain of C. elegans, which has the ability to glow fluorescently green. Then, using a chemical, they induced the plasmid to express the green fluorescence-suppressing gene. Last, they fed the bacteria to C. elegans and found that only those C. elegans that consumed the E. coli with the transgene stopped glowing green.
In addition, Sun and her team programmed E. Coli to produce gene products with different "AND" and "OR" logic gates. Put simply, gene products could be selectively produced only by the combined action of two or more genes, like the mathematical "AND" operation, or if any one gene was expressed, like the mathematical "OR" operation. Once again, using chemical triggers, the researchers initiated an "AND" or "OR" combination of gene expression in the E. Coli needed to silence twitching behavior in C. elegans after the worms fed on the bacteria.
Sun said that their bacteria-based gene silencing system could be easily extended to other living systems for applications in pest control, plant growth promotion and veterinary disease diagnosis.
"Bacteria have a symbiotic relationship with many species, affecting their hosts' metabolism, immunity and behavior," said Sun. "Here, we have taken advantage of the symbiosis between bacteria and a relatively complex organism to engineer a programmable genetic tool that can influence host physiology in a positive way."
https://phys.org/news/2021-08-genetically-good-bacteria-aid-combati...
part 2
Aug 25, 2021
Dr. Krishna Kumari Challa
High cholesterol fuels cancer by fostering resistance to a form of cell death
Chronically high cholesterol levels are known to be associated with increased risks of breast cancer and worse outcomes in most cancers, but the link has not been fully understood.
In a new study appearing online Aug. 24 in the journal Nature Communications, a research team led by the Duke Cancer Institute has identified the mechanisms at work, describing how breast cancer cells use cholesterol to develop tolerance to stress, making them impervious to death as they migrate from the original tumor site.
Most cancer cells die as they try to metastasize—it's a very stressful process. The few that don't die have this ability to overcome the cell's stress-induced death mechanism. researchers now found that cholesterol was integral in fueling this ability.
In the current study using cancer cell lines and mouse models, the researchers found that migrating cancer cells gobble cholesterol in response to stress. Most die.
But in the what-doesn't-kill-you-makes-you-stronger motif, those that live emerge with a super-power that makes them able to withstand ferroptosis, a natural process in which cells succumb to stress. These stress-impervious cancer cells then proliferate and readily metastasize.
The process appears to be used not only by ER-negative breast cancer cells, but other types of tumors, including melanoma. And the mechanisms identified could be targeted by therapies.
https://www.nature.com/articles/s41467-021-25354-4
Dysregulated cholesterol homeostasis results in resistance to 2 ferroptosis and increased cancer cell metastasis, Nature Communications (2021).
https://medicalxpress.com/news/2021-08-high-cholesterol-fuels-cance...
Aug 25, 2021
Dr. Krishna Kumari Challa
Is There Plastic in your Rain? Yes!
Aug 25, 2021
Dr. Krishna Kumari Challa
How the same plant species can program itself to flower at differen...
Researchers led by Professor Caroline Dean have uncovered the genetic basis for variations in the vernalization response shown by plants growing in very different climates, linking epigenetic mechanisms with evolutionary change.
Aug 25, 2021
Dr. Krishna Kumari Challa
Murderers desperate to get rid of evidence might want to consider using bleach to wash away stains. But not just any bleach will do. When old-school chlorine-based bleach is splashed all over blood-stained clothing, even if the clothes are washed ten times, DNA is still detected.
So for the criminal aspiring for perfection, here’s the secret you’ll need to know: It’s the oxygen-producing detergents that will get rid of any incriminating evidence for good.
Researchers at the University of Valencia tested oxygen bleach on blood-stained clothing for two hours and found that it destroys all DNA evidence. Forensic tests such as luminal tests rely on the ability of blood to uptake oxygen: A protein in the blood called hemoglobin (responsible for transporting oxygen throughout the body) reacts with hydrogen peroxide and gives a positive test result.
Chlorine-based detergents contaminate blood, but leave behind intact hemoglobin. However, detergents such as Reckitt Benckiser’s Vanish produce oxygen bubbles, which cause the blood to degrade and no longer uptake oxygen.
Hopefully, anyone actually contemplating cleaning up bloodstains isn’t reading this.
https://www.discovermagazine.com/the-sciences/want-to-get-away-with...
Aug 25, 2021
Dr. Krishna Kumari Challa
Aug 25, 2021