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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

Comment by Dr. Krishna Kumari Challa on May 24, 2022 at 6:35am

'Next generation wonder material' created for first time

For over a decade, scientists have attempted to synthesize a new form of carbon called graphyne with limited success. That endeavor is now at an end.

Graphyne has long been of interest to scientists because of its similarities to the "wonder material" graphene—another form of carbon that is highly valued by industry . 

However, despite decades of work and theorizing, only a few fragments have ever been created before now.

This research, announced last week in Nature Synthesis, fills a longstanding gap in carbon material science, potentially opening brand-new possibilities for electronics, optics and semiconducting material research.

Scientists have long been interested in the construction of new or novel carbon allotropes, or forms of carbon, because of carbon's usefulness to industry, as well as its versatility.

There are different ways carbon allotropes can be constructed depending on how sp2, sp3 and sp hybridized carbon (or the different ways carbon atoms can bind to other elements), and their corresponding bonds, are utilized. The most well-known carbon allotropes are graphite (used in tools like pencils and batteries) and diamonds, which are created out of sp2 carbon and sp3 carbon, respectively.

Using traditional chemistry methods, scientists have successfully created various allotropes over the years, including fullerene and graphene.

However, these methods don't allow for the different types of carbon to be synthesized together in any sort of large capacity, like what's required for graphyne, which has left the theorized material—speculated to have unique electron conducting, mechanical and optical properties—to remain that: a theory.

Part 1

Comment by Dr. Krishna Kumari Challa on May 23, 2022 at 11:53am

Drug treatment for cataracts moves a step closer

A revolutionary new treatment for cataracts has shown extremely positive results in laboratory tests, giving hope that the condition, which currently can only be cured with surgery, could soon be treated with drugs.

Cataract is a clouding of the eye lens that develops over time and affects the quality of vision. It is caused by a disorganization of the proteins in the lens that leads to clumps of protein forming, which scatter light and severely reduce transmission to the retina. Cataracts cause vision loss  and blindness for millions of people worldwide.

Scientists have  been carrying out advanced optical tests on an oxysterol compound that had been proposed as an anti-cataract drug.  In laboratory trials, treatment with the oxysterol compound VP1-001 showed an improvement in refractive index profiles—a key optical parameter that is needed to maintain high focusing capacity—in 61% of lenses. This means that the protein organization of the lens is being restored, resulting in the lens being better able to focus. This was supported by a reduction in lens opacity in 46% of cases.

It has shown that there is a remarkable difference and improvement in optics between eyes with the same type of cataract that were treated with the compound compared to those that were not.

"Improvements occurred in some types of cataract but not in all, indicating that this may be a treatment for specific cataracts. This suggests distinctions may need to be made between cataract types when developing anti-cataract medications. It is a significant step forward towards treating this extremely common condition with drugs rather than surgery.

Oxysterol compounds in mouse mutant αA- and αB-crystallin lenses 2 can improve the optical properties of the lens, Investigative Ophthalmology & Visual Science (2022).

Comment by Dr. Krishna Kumari Challa on May 23, 2022 at 6:56am

Male pheromones improve health of females' eggs

Male pheromones just might be the fountain of youth for aging female animals’ eggs, according to a new study.

In the new study, researchers used the tiny transparent roundworm C. elegans, a well-established model organism commonly used in biology research. Exposure of female roundworms to male pheromones slowed down the aging of the females’ egg cells, resulting in healthier offspring.

Not only did the exposure decrease embryonic death by more than twofold, it also decreased chromosomal abnormalities in surviving offspring by more than twofold. Under the microscope, egg cells also looked younger and healthier, rather than tiny and misshapen, which is common with aging.

To conduct the study, the team aged female roundworms in the presence of a pheromone that is normally produced by male roundworms. The researchers saw that egg quality in females exposed to the pheromone was higher than in control roundworms that did not encounter the pheromone.

Although continuous exposure to male pheromones worked best, even shorter exposure improved overall egg quality. Researchers think this result can be explained by the animals’ “shifting energy budgets.”

Acting outside the body, pheromones are chemicals that animals produce and release to elicit social responses from other members of their species. Pheromones also inform animals about how to budget their finite energy.

When conditions are not conducive to reproduction, female animals will spend resources and energy maintaining their overall body health, including muscles, neurons, intestines and other nonreproductive organs. Sensing male pheromones triggers downstream signaling from the nervous system to the rest of the body, causing the female animals to shift their energy and resources to increasing reproductive health instead. The result? Better eggs but faster decay of the body.

The pheromone tricks the female into sending help to her eggs and shortchanging the rest of her body. It’s not all or nothing, but it’s shifting the balance.

The researchers think this finding potentially could lead to pharmacological interventions that combat infertility issues in humans by improving egg cell quality and delaying the onset of reproductive aging.

Reproductive aging affects everyone. One of the first signs of biological aging is the decreased quality of reproductive cells, which causes reduced fertility, increased incidence of fetal defects including miscarriages, and eventually loss of fertility. By all criteria scientists could think of, male pheromones made the eggs better.

Of course, there are unfortunate trade-offs. When female roundworms neglected the rest of their body to focus their energy on reproductive health, they were more likely to experience early death.

Erin Z. Aprison, Svetlana Dzitoyeva, David Angeles-Albores, Ilya Ruvinsky. A male pheromone that improves the quality of the oogenic germline. Proceedings of the National Academy of Sciences, 2022; 119 (21) DOI: 10.1073/pnas.2015576119

https://news.northwestern.edu/stories/2022/05/male-pheromones-impro....

Comment by Dr. Krishna Kumari Challa on May 23, 2022 at 6:46am

Scientists devise method to prevent deadly hospital infections without antibiotics

 A hospital or medical clinic might be the last place you’d expect to pick up a nasty infection, but that is what happens usually resulting in hundreds of deaths from infection-related complications and billions in direct medical costs.

The biggest culprits, experts say — accounting for two-thirds of these infections — are medical devices like catheters, stents, heart valves and pacemakers, whose surfaces often become covered with harmful bacterial films. But a novel surface treatment developed by a  team of scientists could help improve the safety of these devices and ease the economic burden on the health care system.

The new approach, tested in both laboratory and clinical settings, involves depositing a thin layer of what is known as zwitterionic material on the surface of a device and permanently binding that layer to the underlying substrate using ultraviolet light irradiation. The resulting barrier prevents bacteria and other potentially harmful organic materials from adhering to the surface and causing infection.

In the laboratory, researchers applied the surface treatment to several commonly used medical device materials, then tested the modified materials’ resistance to various types of bacteria, fungi and proteins. They found that the treatment reduced biofilm growth by more than 80% — and in some cases up 93%, depending on the microbial strain.

The modified surfaces exhibited robust resistance against microorganisms and proteins. The surfaces greatly reduced or even prevented biofilm formation.

Brian McVerry, Alexandra Polasko, Ethan Rao, Reihaneh Haghniaz, Dayong Chen, Na He, Pia Ramos, Joel Hayashi, Paige Curson, Chueh‐Yu Wu, Praveen Bandaru, Mackenzie Anderson, Brandon Bui, Aref Sayegh, Shaily Mahendra, Dino Di Carlo, Evgeniy Kreydin, Ali Khademhosseini, Amir Sheikhi, Richard B. Kaner. A Readily Scalable, Clinically Demonstrated, Antibiofouling Zwitterionic Surface Treatment for Implantable Medical Devices. Advanced Materials, 2022; 2200254 DOI: 10.1002/adma.202200254

https://newsroom.ucla.edu/releases/surface-treatment-for-medical-de...

Comment by Dr. Krishna Kumari Challa on May 22, 2022 at 11:27am

Exoskeleton device helps stroke victims regain hand function

Comment by Dr. Krishna Kumari Challa on May 21, 2022 at 1:23pm

However, the pressure of the solar wind seems to play little role in the brightness of said auroras. This suggests that space weather events, such as coronal mass ejections, where masses of charged particles are ejected from the Sun and are associated with higher solar wind pressure, may trigger Martian auroras.

Inside the crustal magnetic field regions, the orientation of the magnetic field and the solar wind seems to play a significant role in the formation of auroras on Mars. At certain orientations, the solar wind seems to be favorable to the magnetic reconnection events or particle acceleration required to produce the ultraviolet glow.

These results, the researchers said, reveal new information on how interactions with the solar wind can generate auroras on a planet stripped of its global magnetic field. This information can be used to help better understand the formation of discrete auroras on very different worlds.

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021JA030238

Part 2

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Comment by Dr. Krishna Kumari Challa on May 21, 2022 at 1:23pm

Mars Has Auroras Without a Global Magnetic Field

Earth's auroras are a glorious wonder, but our planet isn't the only place in the Solar System where these phenomena can be found. An atmospheric glow, albeit sometimes in invisible wavelengths, has been spotted at every planet except Mercury, and even some moons of Jupiter... and even a comet. But Mars is where it gets interesting. The red planet is famous for its lost global magnetic field, an ingredient that plays a crucial role in the formation of aurora elsewhere.

But that doesn't mean Mars is totally magnetism-free. Regions of localized magnetic fields sprout from some regions of the crust, particularly in the southern hemisphere. New analysis has confirmed that these small, local magnetic fields interact with the solar wind in interesting ways to produce Mars's discrete (or structured) ultraviolet auroras.

The new main finding is that inside the strong crustal field region, the aurora occurrence rate depends mostly on the orientation of the solar wind magnetic field, while outside the strong crustal field region, the occurrence rate depends mostly on the solar wind dynamic pressure.

But Mars's global magnetic field decayed fairly early on in the planet's history, leaving behind only patches of magnetism preserved in magnetized minerals in the crust. Ultraviolet images of Mars at night have revealed that auroras tend to form near these crustal magnetic fields, which makes sense if magnetic field lines are required for particle acceleration.  Outside the crustal magnetic field regions, the dynamic pressure of the solar wind plays a significant role in the detection frequency of auroras.

Part 1

Comment by Dr. Krishna Kumari Challa on May 21, 2022 at 9:59am

New method to kill cyberattacks in less than a second

A new method that could automatically detect and kill cyberattacks on our laptops, computers and smart devices in under a second has been created by researchers.

Using artificial intelligence in a completely novel way, the method has been shown to successfully prevent up to 92 percent of files on a computer from being corrupted, with it taking just 0.3 seconds on average for a piece of malware to be wiped out.

The new approach is based on monitoring and predicting the behavior of malware as opposed to more traditional antivirus approaches that analyze what a piece of malware looks like.

By training computers to run simulations on specific pieces of malware, it is possible to make a very quick prediction in less than a second of how the malware will behave further down the line.

Once a piece of software is flagged as malicious the next stage is to wipe it out, which is where the new research comes into play.

Once a threat is detected, due to the fast-acting nature of some destructive malware, it is vital to have automated actions to support these detections.

Matilda Rhode et al, Real-Time Malware Process Detection and Automated Process Killing, Security and Communication Networks (2021). DOI: 10.1155/2021/8933681

https://techxplore.com/news/2022-05-method-cyberattacks.html?utm_so...

Comment by Dr. Krishna Kumari Challa on May 21, 2022 at 9:51am

How one of the X chromosomes in female embryonic stem cells is silenced

In most mammals, females have two X chromosomes and males have one X and one Y chromosome in each of their cells. To avoid a double dose of X-linked genes in females, one of the Xs is silenced early in the developmental process. This silencing is critical, yet how it happens has been relatively mysterious. Two new  studies reveal more about this silencing process and insights that could improve stem cell research.

Human embryonic stem cells (hESCs) hold enormous promise for research into early development as well as for regenerative medicine for diseases ranging from type 1 diabetes to Parkinson's disease. Yet, biologists working with female hESCs in the lab often run into a phenomenon wherein the normally inactivated X chromosome loses this suppression while growing in a culture dish.

If you can't maintain hESCs exactly as such in culture then you can't use them for any downstream application. Researchers set out to determine why X-inactivation erodes under certain experimental conditions over time.

Their primary suspect was the substance used to grow the cells in culture, called media. Cells are grown in media that supply them with chemical instructions called growth factors. These growth factors signal stem cells to keep dividing. One popular medium, called mTeSR1, appeared to be correlated with the loss of a key regulator of X-inactivation, a non-coding strand of RNA called XIST. Another medium, called Xenofree, did not lead to a loss of X-inactivation.

Researchers looked at the differences in the composition of these two media and identified lithium chloride as being present in mTeSR1 but not in Xenofree.

Lithium chloride is sometimes included in media to promote stem cell proliferation, however, it is known to interfere with many cell-signaling pathways by inhibiting GSK-3 proteins. (Inhibitors of GSK-3 proteins have been used to treat several diseases, and lithium, used to treat bipolar disorder, was one of the first natural GSK-3 inhibitors discovered.)

To confirm lithium chloride as the culprit, they added the compound to the Xenofree medium and saw a loss of X-inactivation.

This study suggests that researchers need to be a little more cautious about the use of GSK-3 inhibitors like lithium. They may not only interfere with X inactivation, but other modes of epigenetic transcriptional regulation across the genome.

 Marissa Cloutier et al, Preventing erosion of X-chromosome inactivation in human embryonic stem cells, Nature Communications (2022). DOI: 10.1038/s41467-022-30259-x

Milan Kumar Samanta et al, Activation of Xist by an evolutionarily conserved function of KDM5C demethylase, Nature Communications (2022). DOI: 10.1038/s41467-022-30352-1

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