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Comment by Dr. Krishna Kumari Challa on May 26, 2022 at 1:54pm

How the universe got its magnetic field

When we look out into space, all of the astrophysical objects that we see are embedded in magnetic fields. This is true not only in the neighborhood of stars and planets, but also in the deep space between galaxies and galactic clusters. These fields are weak—typically much weaker than those of a refrigerator magnet—but they are dynamically significant in the sense that they have profound effects on the dynamics of the universe. Despite decades of intense interest and research, the origin of these cosmic magnetic fields remains one of the most profound mysteries in cosmology.

In previous research, scientists came to understand how turbulence, the churning motion common to fluids of all types, could amplify preexisting magnetic fields through the so-called dynamo process. But this remarkable discovery just pushed the mystery one step deeper. If a turbulent dynamo could only amplify an existing field, where did the "seed" magnetic field come from in the first place?

We wouldn't have a complete and self-consistent answer to the origin of astrophysical magnetic fields until we understood how the seed fields arose. New work carried out recently provides an answer that shows the basic processes that generate a field from a completely unmagnetized state to the point where it is strong enough for the dynamo mechanism to take over and amplify the field to the magnitudes that we observe.

Naturally occurring magnetic fields are seen everywhere in the universe. They were first observed on Earth thousands of years ago, through their interaction with magnetized minerals like lodestone, and used for navigation long before people had any understanding of their nature or origin. Magnetism on the sun was discovered at the beginning of the 20th century by its effects on the spectrum of light that the sun emitted. Since then, more powerful telescopes looking deep into space found that the fields were ubiquitous.

And while scientists had long learned how to make and use permanent magnets and electromagnets, which had all sorts of practical applications, the natural origins of magnetic fields in the universe remained a mystery. Recent work has provided part of the answer, but many aspects of this question are still under debate.

Part 1

Comment by Dr. Krishna Kumari Challa on May 26, 2022 at 1:41pm

None of the tissue samples exhibited changes in epigenetic aging. But the researchers did find changes to the way the cells handled energy—their ability to sense nutrients was impacted. This ability plays a major role in cell growth, reproduction and death. The researchers also found changes in mitochondrial activity and in the number of stem cells in their samples. They suggest that epigenetic aging does not predict changes in senescence, nor does it match with age-related changes to telomeres, one of the major indicators of aging in general.

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Epigenetic aging clock predicts the biological age of individual cells

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More information: Sylwia Kabacik et al, The relationship between epigenetic age and the hallmarks of ageing in human cells, Nature Aging (2022). DOI: 10.1038/s43587-022-00220-0

Steve Horvath et al, DNA methylation clocks for dogs and humans, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2120887119

Part 2

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Comment by Dr. Krishna Kumari Challa on May 26, 2022 at 1:40pm

Investigating whether epigenetic aging is the manifestation of one or more aging hallmarks

A team of researchers affiliated with a host of institutions in the U.K. and the U.S. has conducted an investigation into whether epigenetic aging is the manifestation of one or more aging hallmarks. In their paper published in the journal Nature Aging, the group describes subjecting human cells to three kinds of abuse and then testing them to see if the cells aged epigenetically.

Over the past several years, some researchers focusing on the science of aging have become proponents of what is described as epigenetic aging, whereby certain attributes of our bodies age at a rate that may not be consistent with our biological age. That has led to studies aimed at measuring the epigenetic age of people (and other animals) using DNA methylation clocks, ostensibly as a means to circumvent them and allow people to live longer. In this new effort, the researchers studied hallmarks of aging such as exposure to radiation, reproduced them and tested the effects on the pace of epigenetic aging.

The work involved collecting tissue samples from 14 healthy people and dividing them into four groups. One group was subjected to a small dose of radiation, another had some of their cell properties altered to become cancerous, and yet another set was subjected to induced senescence. The fourth group was left undisturbed. Each of the groups represented a hallmark of aging. Exposure to radiation can, for example, make changes to the genome that results in accelerated aging.

Part 1

Comment by Dr. Krishna Kumari Challa on May 25, 2022 at 7:01am

Scientists discover new tools to fight potentially deadly protozoa

Comment by Dr. Krishna Kumari Challa on May 25, 2022 at 6:52am

A candlelight-like glow from a flexible organic LED

Giving off a comfortable glow, candles set the ambiance for a special dinner or just a quiet evening at home. However, some lighting alternatives, such as electronic candles, give off unwanted blue wavelengths that interfere with the body's circadian rhythm. Now, researchers reporting in ACS Applied Electronic Materials have fabricated an improved bendable organic LED that releases candlelight-like light for flexible lighting and smart displays that people can comfortably use at night.

researchers developed organic LEDs that released warm-white light, similar to that produced by candles. However, the devices still emitted some blue wavelength light, which can interfere with sleep because it dampens the body's production of melatonin. These devices were made of solid materials and weren't flexible.

One option for making them bendable is to use a plastic backing, as has been done for other organic LEDs. But plastics don't stand up well to repeated bending. Another option for the backing is mica—a natural mineral with extreme temperature tolerance that can be split into bendable, transparent sheets. So, Jou, Ying-Hao Chu and colleagues wanted to develop an even better organic LED and apply it to a mica backing, creating a bendable candle-like light with a long lifespan.

The researchers deposited a clear indium tin oxide film onto a transparent mica sheet as the LED's anode, which could bend 50,000 times without breaking. Next, the team mixed the luminescent substance N,N'-dicarbazole-1,1'-biphenyl with red and yellow phosphorescent dyes to produce a light-emitting layer. This layer was then placed between electrically conductive solutions with the anode on one side and an aluminum layer on the other side, creating a flexible organic LED.

When a constant current was applied to the device, it produced a bright, warm light with even less blue wavelength emissions than natural candlelight. Calculations showed that exposure to the LED for 1.5 hours would suppress a person's melatonin production by about 1.6%, whereas light from a cold-white compact fluorescent lamp would suppress melatonin production by 29%. The researchers say that the flexibility of their candlelight-like organic LED opens up the design opportunities for blue-light-free nighttime devices.

Tun-Hao Chen et al, Flexible Candlelight Organic LED on Mica, ACS Applied Electronic Materials (2022). DOI: 10.1021/acsaelm.2c00123

Comment by Dr. Krishna Kumari Challa on May 24, 2022 at 12:14pm

First Patient Injected With Experimental Cancer-Killing Virus in New Clinical Trial

An experimental cancer-killing virus has been administered to a human patient for the first time, with hopes the testing will ultimately reveal evidence of a new means of successfully fighting cancer tumors in people's bodies.

The drug candidate, called CF33-hNIS (aka Vaxinia), is what's called an oncolytic virus, a genetically modified virus designed to selectively infect and kill cancer cells while sparing healthy ones. In the case of CF33-hNIS, the modified pox virus works by entering cells and duplicating itself. Eventually, the infected cell bursts, releasing thousands of new virus particles that act as antigens, stimulating the immune system to attack nearby cancer cells. Previous research in animal models has shown the drug can harness the immune system in this way to hunt and destroy cancer cells, but up until now no testing has been done in humans. That's just changed, with co-developers of the drug – the City of Hope cancer care and research center in Los Angeles, and Australia-based biotech company Imugene – now announcing that the first clinical trial in human patients is underway.

https://clinicaltrials.gov/ct2/show/NCT05346484

https://www.sciencealert.com/first-patient-injected-with-experiment...

Comment by Dr. Krishna Kumari Challa on May 24, 2022 at 7:14am

Nuclear pasta, the hardest known substance in the universe

A team of scientists has calculated the strength of the material deep inside the crust of neutron stars and found it to be the strongest known material in the universe.

Neutron stars are born after supernovas, an implosion that compresses an object the size of the sun to about the size of Montreal, making them "a hundred trillion times denser than anything on earth." Their immense gravity makes their outer layers freeze solid, making them similar to earth with a thin crust enveloping a liquid core.

This high density causes the material that makes up a neutron star, known as nuclear pasta, to have a unique structure. Below the crust, competing forces between the protons and neutrons cause them to assemble into shapes such as long cylinders or flat planes, which are known in the literature as 'lasagna' and 'spaghetti,' hence the name 'nuclear pasta.' Together, the enormous densities and strange shapes make nuclear pasta incredibly stiff.

Thanks to their computer simulations, which required 2 million hours worth of processor time or the equivalent of 250 years on a laptop with a single good GPU, Caplan and his colleagues were able to stretch and deform the material deep in the crust of neutron stars.

M. E. Caplan, A. S. Schneider, C. J. Horowitz. The Elasticity of Nuclear Pasta. Physical Review Letters, 2018 [abstract]

https://www.sciencedaily.com/releases/2018/09/180918110836.htm#:~:t....

Comment by Dr. Krishna Kumari Challa on May 24, 2022 at 7:01am

Study reveals evidence that bacteria can live in snake and spider venoms

Newly published research  shows that, contrary to what is commonly believed, the venom of snakes and spiders is actually populated with microbes, including bacteria that could cause infection in people who have suffered a bite.

For decades scientists have thought that animal venom is an entirely sterile environment due to it being full of antimicrobial substances—materials that can kill bacteria.

However, new scientific evidence from research has shown that this is not the case. 

The work, published today in scientific journal Microbiology Spectrum demonstrates how adaptable microorganisms are. The study provides strong genetic and culture evidence that bacteria can not only survive in the venom glands of several species of snakes and spiders, but can also mutate to resist the notoriously toxic liquid that is venom.

The findings also suggest that victims of venomous animal bites may therefore also need to be treated for infections, not just antivenom to tackle the toxins deposited through the bite.

Common diagnostic tools failed to identify these bacteria correctly—if you were infected with these, a doctor would end up giving you the wrong antibiotics, potentially making matters worse.

When researchers sequenced their DNA recently they clearly identified the bacteria and discovered they had mutated to resist the venom. This is extraordinary because venom is like a cocktail of antibiotics, and it is so thick with them, you would have thought the bacteria would not stand a chance. Not only did they stand a chance, they had done it twice, using the same mechanisms.

They also directly tested the resistance of Enterococcus faecalis, one of the species of bacteria they found in the venom of black-necked spitting cobras, to venom itself and compared it to a classic hospital isolate: the hospital isolate did not tolerate the venom at all, but the two isolates from venom  happily grew in the highest concentrations of venom researchers could throw at them.

The researchers say that their study shows the need for clinicians to consider treating snakebite victims not just for tissue destruction, but for infection too, as quickly as possible.

 Elham Esmaeilishirazifard et al, Bacterial Adaptation to Venom in Snakes and Arachnida, Microbiology Spectrum (2022). DOI: 10.1128/spectrum.02408-21. journals.asm.org/doi/10.1128/spectrum.02408-21

Comment by Dr. Krishna Kumari Challa on May 24, 2022 at 6:52am

Low-cost gel film can pluck drinking water from desert air

More than a third of the world's population lives in drylands, areas that experience significant water shortages. Scientists and engineers have developed a solution that could help people in these areas access clean drinking water.

Researchers now developed a low-cost gel film made of abundant materials that can pull water from the air in even the driest climates. The materials that facilitate this reaction cost a mere $2 per kilogram, and a single kilogram can produce more than 6 liters of water per day in areas with less than 15% relative humidity and 13 liters in areas with up to 30% relative humidity.

The research builds on previous breakthroughs from the team, including the ability to pull water out of the atmosphere and the application of that technology to create self-watering soil. However, these technologies were designed for relatively high-humidity environments.

This new work is about practical solutions that people can use to get water in the hottest, driest places on Earth. This could allow millions of people without consistent access to drinking water to have simple, water generating devices at home that they can easily operate.

The researchers used renewable cellulose and a common kitchen ingredient, konjac gum, as a main hydrophilic (attracted to water) skeleton. The open-pore structure of gum speeds the moisture-capturing process. Another designed component, thermo-responsive cellulose with hydrophobic (resistant to water) interaction when heated, helps release the collected water immediately so that overall energy input to produce water is minimized.

The film is flexible and can be molded into a variety of shapes and sizes, depending on the need of the user. Making the film requires only the gel precursor, which includes all the relevant ingredients poured into a mold.

The gel takes 2 minutes to set simply. Then, it just needs to be freeze-dried, and it can be peeled off the mold and used immediately after that.

Youhong Guo et al, Scalable super hygroscopic polymer films for sustainable moisture harvesting in arid environments, Nature Communications (2022). DOI: 10.1038/s41467-022-30505-2

Comment by Dr. Krishna Kumari Challa on May 24, 2022 at 6:38am

Some researchers are now  studying reversible chemistry, which is chemistry that allows bonds to self-correct, allowing for the creation of novel ordered structures, or lattices, such as synthetic DNA-like polymers.

Using a process called alkyne metathesis—which is an organic reaction that entails the redistribution, or cutting and reforming, of alkyne chemical bonds (a type of hydrocarbon with at least one carbon-carbon triple covalent bond)—as well as thermodynamics and kinetic control, the researchers were able to successfully create what had never been created before: A material that could rival the conductivity of graphene but with control.

This could be the next generation wonder material. 

While the material has been successfully created, the scientists still want to look into the particular details of it, including how to create the material on a large scale and how it can be manipulated.

Yiming Hu et al, Synthesis of γ-graphyne using dynamic covalent chemistry, Nature Synthesis (2022). DOI: 10.1038/s44160-022-00068-7

Part 2

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