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Comment by Dr. Krishna Kumari Challa on May 12, 2022 at 10:52am

For the first time, researchers have observed an X-ray explosion on...

When stars like our sun use up all their fuel, they shrink to form white dwarfs. Sometimes such dead stars flare back to life in a super-hot explosion and produce a fireball of X-ray radiation. A research team  has now been able to observe such an explosion of X-ray light for the very first time.

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Scientists solve problem of industrial waste from sugarcane process... Scientists have discovered how to significantly improve the sustainability of the sugarcane industry by turning a major by-product into a valuable chemical used in food, medicines and cosmetics. -- A nontoxic glue for plywood—from glucose, citric acid The go-to materials for building home furniture, décor and floors are composite wood products that come in large sheets. But the glues and resins holding together particleboard, fiberboard and plywood usually contain formaldehyde and could release this probable carcinogen into the air. To develop a nontoxic adhesive, researchers reporting in ACS Applied Materials & Interfaces have combined glucose and citric acid—sugar and an orange juice ingredient—into a strong, water-resistant wood glue for plywood.

Comment by Dr. Krishna Kumari Challa on May 12, 2022 at 10:07am

Magnetism is a collective phenomenon in which the electrons in a material all spin in the same direction. An everyday example is the ferromagnet, which owes its magnetic properties to the alignment of spins. Neighboring electrons can also spin in opposite directions. In this case, the spins still have well-defined directions but there is no magnetization. Frustrated magnets are frustrated because the neighboring electrons try to orient their spins in opposing directions, and when they find themselves in a triangular lattice, they can no longer settle on a common, stable arrangement. The result: a frustrated magnet.

E. M. Smith et al, Case for a U(1)π Quantum Spin Liquid Ground State in the Dipole-Octupole Pyrochlore Ce₂Zr₂O₇, Physical Review X (2022). DOI: 10.1103/PhysRevX.12.021015

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Comment by Dr. Krishna Kumari Challa on May 12, 2022 at 10:07am

Unusual quantum state of matter observed for the first time

It's not every day that someone comes across a new state of matter in quantum physics. Yet this is exactly what an international team of physicists has done recently. 

In a recent article published in the scientific journal Physical Review X, the researchers document a "quantum spin liquid ground state" in a magnetic material created in  lab: Ce₂Zr₂O₇, a compound composed of cerium, zirconium and oxygen.

In quantum physics, spin is an internal property of electrons linked to their rotation. It is spin that gives the material in a magnet its magnetic properties.

In some materials, spin results in a disorganized structure similar to that of molecules in a liquid, hence the expression "spin liquid."

In general, a material becomes more disorganized as its temperature rises. This is the case, for example, when water turns into steam. But the principal characteristic of spin liquids is that they remain disorganized even when cooled to as low as absolute zero (–273°C).

Spin liquids remain disorganized because the direction of spin continues to fluctuate as the material is cooled instead of stabilizing in a solid state, as it does in a conventional magnet, in which all the spins are aligned.

Imagine an electron as a tiny compass that points either up or down. In conventional magnets, the electron spins are all oriented in the same direction, up or down, creating what is known as a "ferromagnetic phase." This is what keeps photos and notes pinned to your fridge.

But in quantum spin liquids, the electrons are positioned in a triangular lattice and form a "ménage à trois" characterized by intense turbulence that interferes with their order. The result is an entangled wave function and no magnetic order.

When a third electron is added, the electron spins cannot align because the two neighboring electrons must always have opposing spins, creating what we call magnetic frustration.

This generates excitations that maintain the disorder of spins and therefore the liquid state, even at very low temperatures."

So how did they add a third electron and cause such frustration?

Enter the frustrated magnet Ce₂Zr₂O₇ created by physicists in a  lab. 

Ce₂Zr₂O₇ is a cerium-based material with magnetic properties. The existence of this compound was known. This new breakthrough was creating it in a uniquely pure form. They used samples melted in an optical furnace to produce a near-perfect triangular arrangement of atoms and then checked the quantum state.

It was this near-perfect triangle that enabled this team  to create magnetic frustration in Ce₂Zr₂O₇.

Their  measurements showed an overlapping particle function—therefore no Bragg peaks—a clear sign of the absence of classical magnetic order. They also observed a distribution of spins with continuously fluctuating directions, which is characteristic of spin liquids and magnetic frustration. This indicates that the material they created behaves like a true spin liquid at low temperatures.

After corroborating these observations with computer simulations, the team concluded that they were indeed witnessing a never-before-seen quantum state.

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Comment by Dr. Krishna Kumari Challa on May 11, 2022 at 8:46am

Distantly related mushrooms gained the ability to make toxin via horizontal gene transfer
A team of researchers affiliated with several institutions in China and the U.S. has found evidence that suggests three distantly related types of mushrooms gained their ability to produce a dangerous toxin via horizontal gene transfer sometime in their past. In their paper published in Proceedings of the National Academy of Sciences, the group describes their genetic analysis of multiple species of mushrooms to determine which genes in three particular species were responsible for producing the same toxin and what it showed them about its origins.

Scientists have known for some time that the three mushrooms—the deadly dapperling, the destroying angel and the funeral bell—are not only toxic, but also have an identical toxin. Some scientists assumed they must have a common ancestor, but the researchers in this new effort suspected something else was afoot because the three species are so distantly related. To get to the bottom of the matter, they obtained samples of the three mushrooms along with samples from 12 others.

To find out which part of their genome was responsible for making the toxins, the researchers sequenced all of their samples. They found two genes that were responsible for creating the toxins and were identical in all three species. A closer look at the genes showed that they were, indeed, distantly related, but it also showed that the genes responsible for producing the toxins were not passed down from a common ancestor. That left just one other possibility—sometime in their past, all three had received a horizontal gene transfer from another, possibly extinct, mushroom.

A horizontal gene transfer occurs when a third party, such as a bacterium, absorbs some of the genome of a host it is infecting and then passes those cells into another host that it infects. The researchers note that horizontal gene transfer is common with bacteria. In many cases, they steal bits of host DNA, add it to their own, and then pass it on to their offspring. Those offspring can then add the new DNA to cells they infect in another host.

Hong Luo et al, Genes and evolutionary fates of the amanitin biosynthesis pathway in poisonous mushrooms, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2201113119

Comment by Dr. Krishna Kumari Challa on May 11, 2022 at 8:41am

Only 3% of potential bacterial drug sources known
The emergence of antibiotic-resistant pathogens and the increasing difficulty in developing new drugs has contributed to global challenges in combating infectious diseases. An extensive bioinformatics survey of around 170,000 bacterial genomes indicates that only three percent of the genomic potential for microbial natural products—chemically diverse bacterial metabolites that form the basis of antibiotic drugs—have been discovered so far. Co-led by Prof Nadine Ziemert of the German Center for Infection Research (DZIF), the survey identified several bacterial genera as producers of highly diverse natural products that could help to overcome the bottleneck in drug development.

Bacterial producers of natural products as sources of drugs such as antibiotics have been studied for decades. However, the rate of new drug discovery has stagnated in recent years. There is uncertainty on how much chemical diversity exists in nature and how many new compounds can still be discovered. Additionally, assumptions that a large portion of natural product-producers and respective biosynthetic pathways have been discovered already have not been investigated.

To understand the true potential of useful biosynthetic pathways and natural products in the bacterial world, an international team of researchers from Germany, the Netherlands and the United States surveyed a large amount of genomic data—around 170,000 bacterial genomes and several thousands of so-called Metagenome Assembled Genomes representing individual microbial taxa from diverse environments. Using a genome mining strategy, the team identified so-called Biosynthetic Gene Clusters (BGCs)—clusters of genes in bacterial genomes that jointly encode the biosynthesis pathways of natural products. Grouping the BGCs into gene cluster families according to similarity, the researchers developed tools that allow the study of the biosynthetic diversity represented in the bacterial genome database.

This bioinformatics genome mining approach reveals that only three percent or even less of the genomic potential for the production of natural products has been discovered so far.

Based on the mined data, the researchers identified bacterial taxa that showed high biosynthetic potential, among them multiple unexplored taxonomic groups. 

Athina Gavriilidou et al, Compendium of specialized metabolite biosynthetic diversity encoded in bacterial genomes, Nature Microbiology (2022). DOI: 10.1038/s41564-022-01110-2

Comment by Dr. Krishna Kumari Challa on May 10, 2022 at 12:32pm

What is watermelon snow?

Otherwise known as glacier blood, watermelon snow is found worldwide in mountains and polar regions. The pink-red snow has a faintly fruity smell but is reported to have laxative effects if eaten.

The watermelon colour comes from freshwater green algae called Chlamydomonas nivalis. In summer, the algae produce a red pigment to protect themselves from the Sun’s intense rays. This pigment belongs to a large group of carotenoid substances, many of which are found in brightly coloured fruits and vegetables such as tomatoes and carrots.

Unfortunately, the pigment reduces snow’s ability to reflect heat, leading to faster melting rates.

Comment by Dr. Krishna Kumari Challa on May 10, 2022 at 11:59am

Researchers invent chameleon metal that acts like many others

A team of energy researchers  has invented a device that electronically converts one metal so that it behaves like another for use as a catalyst in chemical reactions. The device, called a "catalytic condenser," is the first to demonstrate that alternative materials that are electronically modified to provide new properties can yield faster, more efficient chemical processing.

The invention opens the door for new catalytic technologies using non-precious metal catalysts for important applications such as storing renewable energy, making renewable fuels, and manufacturing sustainable materials.

In order to develop this method for tuning the catalytic properties of alternative materials, the researchers relied on their knowledge of how electrons behave at surfaces. The team successfully tested a theory that adding and removing electrons to one material could turn the metal oxide into something that mimicked the properties of another.

Tzia Ming Onn et al, Alumina Graphene Catalytic Condenser for Programmable Solid Acids, JACS Au (2022). DOI: 10.1021/jacsau.2c00114

Comment by Dr. Krishna Kumari Challa on May 9, 2022 at 9:26am

Combining certain meds with ibuprofen can permanently injure kidneys

Anyone who is taking a diuretic and a renin-angiotensin system (RSA) inhibitor for high blood pressure should be cautious about also taking ibuprofen, according to new research.

Diuretics and RSA inhibitors are commonly prescribed together for people with hypertension and are available under various pharmaceutical brand names. Painkillers such as ibuprofen are available over-the-counter in most pharmacies and stores in popular brands.

Researchers used computer-simulated drug trials to model the interactions of the three drugs and the impact on the kidney. They found that in people with certain medical profiles, the combination can cause acute kidney injury, which in some cases can be permanent.

It's not that everyone who happens to take this combination of drugs is going to have problems. But the research shows it's enough of a problem that you should exercise caution.

Computer-simulated drug trials can quickly produce results that would take much longer in human clinical trials.

The research, in this case, can also speak directly to the many people who are taking drugs for hypertension and may reach for a painkiller with ibuprofen without giving it much thought.

Diuretics are a family of drugs that make the body hold less water. Being dehydrated is a major factor in acute kidney injury, and then the RAS inhibitor and ibuprofen hit the kidney with this triple whammy.

So scientists advice: If you happen to be on these hypertension drugs and need a painkiller, consider acetaminophen instead.

Jessica Leete et al, Determining risk factors for triple whammy acute kidney injury, Mathematical Biosciences (2022). DOI: 10.1016/j.mbs.2022.108809

Comment by Dr. Krishna Kumari Challa on May 8, 2022 at 1:41pm

Depending on your parents and very little on how you live, your longevity or, as our paper claims, your response to COVID-19 is a function of who you were when you were born," he said, "which is kind of a big deal."

To build this model the researchers used publicly available data on COVID-19 mortality from the Center for Disease Control and US Census Bureau and studies on telomeres, many of which were published by the co-authors over the past two decades.

Assembling telomere length information about a person or specific demographic, he said, could help doctors know who was less susceptible. And then they could allocate resources, such as booster shots, according to which populations and individuals may be more susceptible to COVID-19.

https://www.washington.edu/news/2022/05/06/model-finds-covid-19-dea...'s%20ability%20to,virus%20that%20causes%20the%20disease.

Part 2

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Comment by Dr. Krishna Kumari Challa on May 8, 2022 at 1:39pm

Model finds COVID-19 deaths among elderly may be due to genetic limit on cell division

 Your immune system's ability to combat COVID-19, like any infection, largely depends on its ability to replicate the immune cells effective at destroying the SARS-CoV-2 virus that causes the disease. These cloned immune cells cannot be infinitely created, and a key hypothesis of a new University of Washington study is that the body's ability to create these cloned cells falls off significantly in old age.

According to a model created by UW research professor James Anderson, this genetically predetermined limit on your immune system may be the key to why COVID-19 has such a devastating effect on the elderly. Anderson is the lead author of a paper published March 31 in The Lancet eBioMedicine detailing this modeled link between aging, COVID-19 and mortality.

"When DNA split in cell division, the end cap—called a telomere—gets a little shorter with each division," explains Anderson, who is a modeler of biological systems in the School of Aquatic and Fishery Sciences. "After a series of replications of a cell, it gets too short and stops further division. Not all cells or all animals have this limit, but immune cells in humans have this cell life."

The average person's immune system coasts along pretty good despite this limit until about 50 years old. That's when enough core immune cells, called T cells, have shortened telomeres and cannot quickly clone themselves through cellular division in big enough numbers to attack and clear the COVID-19 virus, which has the trait of sharply reducing immune cell numbers, Anderson said. Importantly, he added, telomere lengths are inherited from your parents. Consequently, there are some differences in these lengths between people at every age as well as how old a person becomes before these lengths are mostly used up.

Anderson said the key difference between this understanding of aging, which has a threshold for when your immune system has run out of collective telomere length, and the idea that we all age consistently over time is the "most exciting" discovery of his research.

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