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Comment by Dr. Krishna Kumari Challa on May 13, 2021 at 10:08am

How to thermally cloak an object

Do you feel the heat? To a thermal camera, which measures infrared radiation, the heat that we can feel is visible, like the heat of a traveler in an airport with a fever or the cold of a leaky window or door in the winter.

Researchers now report a theoretical way of mimicking thermal objects or making objects invisible to thermal measurements. 

The method allows for fine-tuning of heat transfer even in situations where the temperature changes in time, the researchers say. One application could be to isolate a part that generates heat in a circuit (say, a power supply) to keep it from interfering with heat sensitive parts (say, a thermal camera). Another application could be in industrial processes that require accurate temperature control in both time and space, for example controlling the cooling of a material so that it crystallizes in a particular manner.

Just as our eyes see objects if they emit or reflect light, a thermal camera can see an object if it emits or reflects infrared radiation. In mathematical terms, an object could become invisible to a thermal camera if heat sources placed around it could mimic heat transfer as if the object wasn't there.

The novelty in the team's approach is that they use heat pumps rather than specially crafted materials to hide the objects. A simple household example of a heat pump is a refrigerator: to cool groceries it pumps heat from the interior to the exterior. Using heat pumps is much more flexible than using carefully crafted materials. So at least from the perspective of thermal measurements they can make an apple appear as an orange.

The researchers carried out the mathematical work needed to show that, with a ring of heat pumps around an object, it's possible to thermally hide an object or mimic the heat signature of a different object.

The work remains theoretical

Active Thermal Cloaking and Mimicking, Proceedings of the Royal Society A (2021). royalsocietypublishing.org/doi … .1098/rspa.2020.0941

https://phys.org/news/2021-05-thermally-cloak.html?utm_source=nwlet...

Comment by Dr. Krishna Kumari Challa on May 12, 2021 at 1:23pm

Potentially Deadly 'Black Fungus' Keeps Showing Up in COVID-19 Patients in India

Potentially fatal 'black fungus' infections on the rise in India's COVID-19 patients

Some COVID-19 patients in India have developed a rare and potentially fatal fungal infection called mucormycosis, also known as "black fungus," according to news reports.

Mucormycosis is caused by a group of molds called mucormycetes, which grow in soil and decaying organic matter, such as rotting leaves and wood. It is ubiquitous and found in soil and air and even in the nose and mucus of healthy people.

The mold can enter the body through cuts and other abrasions in the skin, or the infection can take hold in the sinuses or lungs after people breathe in the fungal spores. Once inside the body, the fungus can sometimes spread through the bloodstream and affect other organs, such as the brain, eyes, spleen and heart.

Most commonly, mucormycosis strikes those with weakened immune systems, including those with diabetes and those taking medicines that suppress immune activity. Now, an increasing number of COVID-19 patients in India appear to be contracting the infection. 

Cases are appearing throughout India now. 

The rise in cases may be connected to the use of steroids in hospitalized COVID-19 patients, since the drugs suppress the immune system.

And those with diabetes start out at increased risk for the infection, even before taking steroids.

"Diabetes lowers the body's immune defenses, coronavirus exacerbates it, and then steroids which help fight COVID-19 act like fuel to the fire. In addition, many families have had to treat relatives for COVID-19 at home, meaning people may become exposed to the mold after receiving medicine or oxygen therapy in less-than-sterile conditions.

https://www.livescience.com/black-fungus-infection-coronavirus-indi...

Comment by Dr. Krishna Kumari Challa on May 12, 2021 at 1:10pm

SARS-CoV-2 coronavirus spike protein under siege

This is video of a SARS-CoV-2 spike protein under siege. The little blobs buzzing around it are called lectins, and they could be the secret weapon in a new defence against COVID-19, new research has found. 

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Most COVID-19 drugs currently in clinical trials are designed to block receptor sites on our cells -- the little doors on the surface of our cells that the SARS-CoV-2 spike protein breaches to gain access. But this treatment would be different, targeting the spike protein itself. The protein hides from our immune system by covering itself with sugar molecules called glycans. These glycans are a disguise that helps the virus get in the door. What if, instead of trying to block the door, you gummed up the key instead?

Researchers developed the largest lectin library in the world to find two lectins that are particularly good at binding to glycans on the SARS-CoV-2 spike protein. These lectins are the gum on the key, and could be the starting point for a lectin-based drug to combat COVID-19. The best part? The glycan sites that the spike protein uses for its disguise show up in all circulating variants of the SARS-CoV-2 virus.

Not only have the researchers learned how these lectins bind to the spike protein, they've recorded it happening.

https://www.biorxiv.org/content/10.11...

Comment by Dr. Krishna Kumari Challa on May 12, 2021 at 11:50am

New material to treat wounds can protect against resistant bacteria

Researchers at Chalmers University of Technology, Sweden, have developed a new material that prevents infections in wounds, a specially designed hydrogel that works against all types of bacteria, including antibiotic-resistant strains. The new material offers great hope for combating a growing global problem.

After testing the new hydrogel on different types of bacteria, researchers observed a high level of effectiveness, including against those which have become resistant to antibiotics.

The active substance in the new bactericidal material consists of antimicrobial peptides, small proteins found naturally in the immune system.

"With these types of peptides, there is a very low risk for bacteria to develop resistance against them, since they only affect the outermost membrane of the bacteria. That is perhaps the foremost reason why they are so interesting.

Researchers have long tried to find ways to use these peptides in medical applications, but so far without much success. The problem is that they break down quickly when they come into contact with bodily fluids such as blood. The current study describes how the researchers managed to overcome the problem through the development of a nanostructured hydrogel, into which the peptides are permanently bound, creating a protective environment.

Saba Atefyekta et al, Antimicrobial Peptide-Functionalized Mesoporous Hydrogels, ACS Biomaterials Science & Engineering (2021). DOI: 10.1021/acsbiomaterials.1c00029

https://phys.org/news/2021-05-material-wounds-resistant-bacteria.ht...

Comment by Dr. Krishna Kumari Challa on May 12, 2021 at 11:07am

Estimation of total mortality due to COVID-19

A team of researchers at the University of Washington Institute for Health Metrics and Evaluation (IHME) has found evidence that suggests the number of people who have died due to COVID-19 is much higher than official reports would indicate. They have undertaken a country-by-country analysis of deaths due to COVID-19 that includes factors associated with the pandemic as a whole and have published their results on the IHME website.

Scientists have calculated total number of people died due to covid:

 By May 3, 2021, the total number of COVID-19 deaths in the world was 6.93 million, a figure that is more than two times higher than the reported number of deaths of 3.24 million.

India: Total number of people actually died due to copvid-19: 6,54,935

Reported deaths: 2, 21,181

Source: http://www.healthdata.org/special-analysis/estimation-excess-mortal...

Comment by Dr. Krishna Kumari Challa on May 12, 2021 at 10:01am

Scientists catch exciting magnetic waves in action in the Sun's photosphere

Researchers have confirmed the existence of magnetic plasma waves, known as Alfvén waves, in the Sun's photosphere. The study, published in Nature Astronomy, provides new insights into these fascinating waves that were first discovered by the Nobel Prize winning scientist Hannes Alfvén in 1947.

The vast potential of these waves resides in their ability to transport energy and information over very large distances due to their purely magnetic nature. The direct discovery of these waves in the solar photosphere, the lowest layer of the solar atmosphere, is the first step towards exploiting the properties of these magnetic waves.

The ability for Alfvén waves to carry energy is also of interest for solar and plasma-astrophysics as it could help explain the extreme heating of the solar atmosphere—a mystery that has been unsolved for over a century.

Alfvén waves form when charged particles (ions) oscillate in response to interactions between magnetic fields and electrical currents.

Within the solar atmosphere bundles of magnetic fields, known as solar magnetic flux tubes, can form. Alfvén waves are though to manifest in one of two forms in solar magnetic flux tubes; either axisymmetric torsional pertubations (where symmetric oscillations occur around the flux tube axis) or anti-symmetric torsional pertubations (where oscillations occur as two swirls rotating in opposite directions in the flux tube).

Despite previous claims, torsional Alfvén waves have never been directly identified in the solar photosphere, even in their simplest form of axisymmetric oscillations of magnetic flux tubes.

In this study, the researchers used high resolution observations of the solar atmosphere, made by the European Space Agency's imager IBIS, to prove the existence of anti-symmetric torsional waves first predicted almost 50 years ago.

They also found that these waves could be used to extract vast amounts of energy from the solar photosphere, confirming the potential of these waves for a wide range of research areas and industrial applications.

Marco Stangalini et al. Torsional oscillations within a magnetic pore in the solar photosphere, Nature Astronomy (2021). DOI: 10.1038/s41550-021-01354-8

https://phys.org/news/2021-05-scientists-magnetic-action-sun-photos...

Comment by Dr. Krishna Kumari Challa on May 11, 2021 at 12:31pm

Targeting viral RNA: The basis for next-gen broad spectrum anti-viral drugs

A new approach to tackling viruses by targeting the 'control center' in viral RNA could lead to broad spectrum anti-viral drugs and provide a first line of defense against future pandemics, according to new research.

In a new study, published in Angewandte Chemie, researchers have shown how this approach could be effective against the SARS-CoV-2 virus responsible for the COVID-19 pandemic. Earlier modeling and in vitro analysis by the team and published in Chemical Science has also shown effectiveness against the HIV virus.

The technique proposed by the team uses cylindrically-shaped molecules which can block the function of a particular section at one end of the RNA strand. These RNA sections, known as untranslated RNA, are essential for regulating the replication of the virus.

Untranslated RNA contain junction points and bulges—essentially small holes in the structure– which are normally recognized by proteins or other pieces of RNA—events that are critical for viral replication to occur. The cylindrical molecules are attracted to these holes, and once they slide into them, the RNA closes around them, forming a precise fit, which consequently will interfere with the virus's ability to replicate.

Lazaros Melidis et al. Supramolecular cylinders target bulge structures in the 5' UTR of the RNA genome of SARS‐CoV‐2 and inhibit viral replication, Angewandte Chemie (2021). DOI: 10.1002/ange.202104179

Lazaros Melidis et al. Targeting structural features of viral genomes with a nano-sized supramolecular drug, Chemical Science (2021). DOI: 10.1039/D1SC00933H

https://phys.org/news/2021-05-viral-rna-basis-next-gen-broad.html?u...

Comment by Dr. Krishna Kumari Challa on May 11, 2021 at 12:25pm

How viruses and bacteria can reach drinking water wells

Induced bank filtration is a key and well-established approach to provide drinking water supply to populated areas located along rivers or lakes and with limited access to groundwater resources. It is employed in several countries worldwide, with notable examples in Europe, the United States, and parts of Africa. Contamination of surface waters poses a serious threat to attaining drinking water standards. In this context, human pathogenic microorganisms such as some viruses and bacteria, originating from the discharge of wastewater treatment plants, form a major contaminant group. A detailed study at an induced bank filtration site along the Rhine river in Germany has now linked transport of bacteria to seasonal dynamics. Key results of the study show that floods should be considered as particular threats, because they can reduce the purification capacity of bank filtration, thus leading to an increase in the concentrations of bacteria in groundwater. Changes in properties of the riverbed sediments over the course of a year can markedly influence the purification capacity of bank filtration and these dynamics may need to be considered in risk assessment practices.

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Hidden within African diamonds, a billion-plus years of deep-Earth ...

Diamonds are sometimes described as messengers from the deep earth; scientists study them closely for insights into the otherwise inaccessible depths from which they come. But the messages are often hard to read. Now, a team has come up with a way to solve two longstanding puzzles: the ages of individual fluid-bearing diamonds, and the chemistry of their parent material. The research has allowed them to sketch out geologic events going back more than a billion years—a potential breakthrough not only in the study of diamonds, but of planetary evolution.

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Understanding astronaut muscle wasting at the molecular level

Researchers from the University of Tsukuba have sent mice into space to explore effects of spaceflight and reduced gravity on muscle atrophy, or wasting, at the molecular level.

Comment by Dr. Krishna Kumari Challa on May 11, 2021 at 12:23pm

Firefighting chemical found in sea lion and fur seal pups

A chemical that the NSW government has recently partially banned in firefighting has been found in the pups of endangered Australian sea lions and in Australian fur seals.

The new research—part of a long-term health study of seals and sea lions in Australia—identified the chemicals in animals at multiple colonies in Victoria and South Australia from 2017 to 2020.

As well as in pups, the chemicals (Per- and polyfluoroalkyl substances - 'PFAS') were detected in juvenile animals and in an adult male. There was also evidence of transfer of the chemicals from mothers to newborns.

PFAS have been reported to cause cancer, reproductive and developmental defects, endocrine disruption and can compromise immune systems. Exposure can occur through many sources including through contaminated air, soil and water, and common household products containing PFAS. In addition to being used in firefighting foam, they are frequently found in stain repellents, polishes, paints and coatings.

The researchers think the seals and sea lions ingested the chemicals through their fish, crustacean, octopus and squid diets.

Shannon Taylor et al, Per and polyfluoroalkyl substances (PFAS) at high concentrations in neonatal Australian pinnipeds, Science of The Total Environment (2021). DOI: 10.1016/j.scitotenv.2021.147446

https://phys.org/news/2021-05-firefighting-chemical-sea-lion-fur.ht...

Comment by Dr. Krishna Kumari Challa on May 11, 2021 at 12:18pm

Cricket bats should be made from bamboo not willow, study finds

Bamboo cricket bats are stronger, offer a better 'sweet spot' and deliver more energy to the ball than those made from traditional willow, tests conducted by the University of Cambridge show. Bamboo could, the study argues, help cricket to expand faster in poorer parts of the world and make the sport more environmentally friendly.

compared the performance of specially made prototype laminated bamboo cricket bats, the first of their kind, with that of typical willow bats. Their investigations included microscopic analysis, video capture technology, computer modelling, compression testing, measuring how knocking-in improved surface hardness, and testing for vibrations.

The study, published today in The Journal of Sports Engineering and Technology, shows that bamboo is significantly stronger—with a strain at failure more than three times greater—than willow and able to hold much higher loads, meaning that bats made with bamboo could be thinner while remaining as strong as willow. This would help batsmen as lighter blades can be swung faster to transfer more energy to the ball. The researchers also found that bamboo is 22% stiffer than willow which also increases the speed at which the ball leaves the bat.

Ben Tinkler-Davies et al, Replacing willow with bamboo in cricket bats, Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology (2021). DOI: 10.1177/17543371211016592

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During manufacture, the surface of cricket bats is compressed to create a hardened layer. When the team compared the effect of this 'knock-in' process on both materials, they found that after 5 hours bamboo's surface hardness had increased to twice that of pressed willow.

Perhaps most excitingly, they found that the sweet-spot on their prototype bamboo blade performed 19% better than that on a traditional willow bat. This sweet-spot was about 20 mm wide and 40 mm long, significantly larger than on a typical willow bat, and better still, was positioned closer to the toe (12.5 cm from the toe at its sweetest point).

This is a batsman's dream. The sweet-spot on a bamboo bat makes it much easier to hit a four off a Yorker for starters, but it's exciting for all kinds of strokes. We'd just need to adjust our technique to make the most of it, and the bat's design requires a little optimisation too.

https://techxplore.com/news/2021-05-cricket-bamboo-willow.html?utm_...

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