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Comment by Dr. Krishna Kumari Challa on December 3, 2024 at 11:19am

Cooperative motion by atoms protects glass from fracturing

What if glass doesn't break?

We've all experienced the moment of panic when a glass slips from our hands, shattering into pieces upon hitting the ground. What if this common mishap could become a thing of the past?

Now, a new discovery by researchers  has offered insights into how glass resists breakage, potentially paving the way for highly durable, break-resistant materials. The breakthrough has wide ranging implications for glass-related industries.

Details of their findings are published in the journal Acta Materialia.

Glass, while strong, is prone to breaking when stress exceeds its tolerance, but interestingly, the movement of atoms and molecules within glass can relax internal stress, making the material more resistant to fractures.

Although we know that some atoms 'jump' into nearby empty spaces, how this process alleviates stress has long been a mystery till now.

Scientists uncovered a previously unknown mechanism of stress relaxation in ionic glass, a model system of glass now.

Their research utilized state-of-the-art synchrotron radiation experiments and computer simulations to observe atomic motions in glass on a nanosecond-to-microsecond timescale.

The team discovered that when some atoms within the glass "jump" into nearby empty spaces, surrounding groups of atoms slowly move together to fill the void. This interplay of atomic jumps and collective motion reduces internal stress, protecting the glass from breaking under external force.

The research team plans to explore whether similar atomic mechanisms operate in other types of glass. Their ultimate goal is to establish universal guidelines for designing glass with superior impact resistance, which could revolutionize applications requiring durable materials.

 Makina Saito et al, Discovery of collective nonjumping motions leading to Johari–Goldstein process of stress relaxation in model ionic glass, Acta Materialia (2024). DOI: 10.1016/j.actamat.2024.120536

Comment by Dr. Krishna Kumari Challa on December 3, 2024 at 10:37am

Proof-of-concept study demonstrates self-assembling electronics

Researchers have demonstrated a new technique for self-assembling electronic devices. The proof-of-concept work was used to create diodes and transistors, and paves the way for self-assembling more complex electronic devices without relying on existing computer chip manufacturing techniques.

The paper, "Guided Ad infinitum Assembly of Mixed-Metal Oxide Arrays from Liquid Metal," is published open access in the journal Materials Horizons.

Julia J Chang et al, Guided Ad infinitum Assembly of Mixed-Metal Oxide Arrays from Liquid Metal, Materials Horizons (2024). DOI: 10.1039/D4MH01177E

Comment by Dr. Krishna Kumari Challa on December 3, 2024 at 10:02am

New spin quantum battery can be charged without an external field

Over the past few years, some researchers have been working on alternative energy storage systems that leverage the principles of quantum mechanics. These systems, known as quantum batteries, could be more efficient and compact than conventional battery technologies, while also achieving faster charging times.

In a recent paper published in Physical Review Letters, a research group  introduced a new spin quantum battery, a battery that leverages the spin degrees of freedom of particles to store and release energy. This battery is charged in a unique and advantageous way, without the need for an external field.

This  quantum battery can be seen as the intercalation of two collections of ½-spins, the simplest possible quantum systems. By properly changing the interaction between the elements of the two chains, for example by shifting one with respect to the other, it becomes possible to trap energy into the quantum battery in a stable way.

This allows their battery to be charged via a new mechanism that does not rely on the presence of an external field.

 Riccardo Grazi et al, Controlling Energy Storage Crossing Quantum Phase Transitions in an Integrable Spin Quantum Battery, Physical Review Letters (2024). DOI: 10.1103/PhysRevLett.133.197001. On arXiv: DOI: 10.48550/arxiv.2402.09169

Comment by Dr. Krishna Kumari Challa on December 3, 2024 at 9:51am

The modified α-hemolysin successfully traveled to the cell membrane and embedded itself. Following this, the peptide inserts could successfully translocate across the membrane, demonstrating protein transport.

Peptides containing up to 50 amino acids could be inserted into α-hemolysin without disrupting pore formation, membrane insertion, and protein functionality.

The researchers further found that the translocated peptides remained accessible on the external side of the membrane. This suggests they could be used for assembling tissue-like structures, as their accessibility allows for further interactions and organization in the external environment.
By generating one population of artificial cells that translocate negatively charged peptides across their membrane and another population of artificial cells that translocate positively charged peptides, we can create a tissue-like structure because artificial cells with a negatively charged outer membrane will bind to artificial cells with a positively charged membrane.
The researchers also added a system to detect if the cells can communicate with each other, where cells produce a visible (fluorescent) signal when they receive a signal from other cells. This could help with the creation of more complex and functional artificial tissues for future applications.

With the possibility of developing artificial tissues and potential drug delivery systems, the novel method demonstrates a pivotal step in cell research.

 Alexander Harjung et al, Encoding extracellular modification of artificial cell membranes using engineered self-translocating proteins, Nature Communications (2024). DOI: 10.1038/s41467-024-53783-4, www.nature.com/articles/s41467-024-53783-4

Part 2

Comment by Dr. Krishna Kumari Challa on December 3, 2024 at 9:48am

Scientists develop self-sustained protein transport and tissue assembly in artificial cells

In a new Nature Communications study, scientists have developed a novel method for artificial cells to interact with their external environment without the need for complex modification processes.

This method could open new frontiers in tissue engineering, drug delivery, and cell processes.

Biological cells are protected by a membrane, made of phospholipids, which modulates interactions with the outside environment. Recreating this in artificial cells is challenging, requiring manual external modification of the membrane.

This is particularly true for protein translocation or movement across the membrane. The present study addresses this problem by developing a method in which artificial cells modify their own membrane.

For the study, the researchers aimed to functionalize the cell membrane to enable protein transport across the membrane and assemble them into tissue-like structures afterward.

Biological channels typically use ion channels and transporters to exchange substances across the membrane. In artificial cells, this interaction has to be replicated manually. The researcher can change the membrane composition to achieve this, which is very different from how natural cells interact with their environment.

To overcome this problem, the researchers developed a method with which you can encode modification of the outer membrane, and thereby interact with the external environment, into the artificial cell genome.

To do so, the researchers chose a pore-forming protein called α-hemolysin. This is a protein produced by Staphylococcus aureus, the bacteria responsible for causing staph infections. It is technically termed a toxin since it forms holes in cell membranes.

But it has the unique ability to be expressed as a soluble monomer, which upon contact with a lipid bilayer (cell membrane) spontaneously assembles into a transmembrane protein.

The researchers not only used the α-Hemolysin as a pore-forming protein but also modified the artificial cells to produce the protein themselves. By having a self-sustaining system, the researchers do not need to add the protein each time.

Part 1

Comment by Dr. Krishna Kumari Challa on November 30, 2024 at 11:25am

Homo juluensis: Possible new ancient human species uncovered by researchers

Researcher say they may have found a new human species called Homo juluensis, which includes mysterious groups like the Denisovans—ancient human relatives whose histories are still being uncovered.

Homo juluensis lived approximately 300,000 years ago in eastern Asia, hunted wild horses in small groups, and made stone tools and possibly processed animal hides for survival before disappearing around 50,000 years ago.

It was proposed that the new species include the enigmatic Denisovans, a population known primarily through DNA evidence from a few physical remains found in Siberia, and a few fossils found in Tibet and Laos. More research is clearly needed to test this relationship, which is primarily based on similarities between jaw and teeth fossils from these different sites.

This study clarifies a hominin fossil record that has tended to include anything that cannot easily be assigned to Homo erectus, Homo neanderthalensis or Homo sapiens.

 Christopher J. Bae et al, Making sense of eastern Asian Late Quaternary hominin variability, Nature Communications (2024). DOI: 10.1038/s41467-024-53918-7

Comment by Dr. Krishna Kumari Challa on November 30, 2024 at 11:16am

Satellite evidence points to climate-induced poisoning of over 300 African elephants

A new study  has provided further evidence that the deaths of 350 African elephants in Botswana during 2020 were the result of drinking from water holes where toxic algae populations had exploded due to climate change.

The lead author of the report says their analysis shows animals were very likely poisoned by watering holes where toxic blooms of blue-green algae, or cyanobacteria, had developed after a very wet year followed a very dry one.

Botswana is home to a third of all African elephants, and this unprecedented die-off within their largest remaining population underlines the escalating concerns surrounding the impact of drought and climate change on the Okavango Delta, one of the most important ecosystems in the world.

Elephant carcasses were first spotted in the north-eastern sector of the country's Okavango Delta between May and June 2020, but poaching was soon ruled out as the cause.

The event sparked global concern, with a total of 350 elephants now known to have died.

Toxins produced by the algae growing in watering holes was one suspected cause, though evidence has remained inconclusive, in part because it occurred during the COVID-19 pandemic when movements were restricted, and this prevented the collection of samples at the time.

The deaths of 25 elephants in neighboring Zimbabwe from septicemia in the same year cast some doubt on algal toxins being the reason for the Botswana deaths.

However, writing in the journal Science of The Total Environment, the team say their analysis all but confirms toxic algae as the cause.

Combining satellite data and spatial analysis, the team examined the relationship between about 3,000 waterholes and the locations of deceased elephants.

Their analysis revealed waterholes near the carcasses showed elevated algal levels and repeated bloom events in 2020 compared to previous years—particularly during the period associated with the mass mortality event.

The team also showed that decayed elephant carcasses were more spread out across the landscape than fresh carcasses, indicating that the die-off in 2020 was different from typical elephant mortality patterns.

After drinking, elephants were estimated to have walked an average of 16.5 km from the toxic waterholes and died within about 88 hours of exposure.

Southern Africa is projected to become drier and hotter under climate changes, and as a result waterholes across this region will likely be drier for more months of the year. Our findings point to the potential negative effects on water quantity and quality, and the catastrophic repercussions on animals, this could have.

https://www.sciencedirect.com/science/article/pii/S0048969724076824...

Davide Lomeo et al, Remote sensing and spatial analysis reveal unprecedented cyanobacteria bloom dynamics associated with elephant mass mortality, Science of The Total Environment (2024). DOI: 10.1016/j.scitotenv.2024.177525

Comment by Dr. Krishna Kumari Challa on November 30, 2024 at 11:06am

New hydrovoltaic cell continuously generates electricity with little water and no sunlight

A team of engineers  has modified the approach used to generate electricity with a hydrovoltaic cell, building one that uses little water and no sunlight. Their study is published in the journal Nature Communications.

Hydrovoltaic cells generate electricity by capturing the energy from interactions between water and other surfaces. Such interactions typically rely on sunlight as the instigating power source. As the researchers with this new effort note, the traditional approach results in a hydrovoltaic cell that needs a continuous source of water and that typically only operates in dry environments. In this new study, the research team  overcame both problems to create a new kind of hydrovoltaic cell.

To allow their cell to operate in virtually any climate, the research team built their cell inside a hermetically sealed container—they call the result a hermetic hydrovoltaic cell (HHC). Inside, they placed a double-layer wicking agent made of tissue paper and carbon black. A small amount of water added to the HHC is continuously circulated due to changes in ambient temperature and capillary flow in the tissue paper.

The HHC generates power using the energy of ambient heat as the instigating power source. Testing showed the cell is capable of producing electricity for up to 160 hours without the addition of any more water. The researchers suggest such a cell would be an ideal candidate for people living in water-poor areas.

Further testing showed that exposure to strong sunlight increased electrical output. The researchers found this was due to energy from the sunlight increasing the rate of absorption by the black carbon, which in turn led to an increased moisture gradient.

 Renxuan Yuan et al, Hermetic hydrovoltaic cell sustained by internal water circulation, Nature Communications (2024). DOI: 10.1038/s41467-024-54216-y

Comment by Dr. Krishna Kumari Challa on November 30, 2024 at 9:32am

Modified ribosomes could be a possible mechanism of antibiotic resistance

Bacteria modify their ribosomes when exposed to widely used antibiotics, according to research published in Nature Communications. The subtle changes might be enough to alter the binding site of drug targets and constitute a possible new mechanism of antibiotic resistance.

Escherichia coli is a common bacterium which is often harmless but can cause serious infections. Researchers exposed E. coli to streptomycin and kasugamycin, two drugs which treat bacterial infections. Streptomycin has been a staple in treating tuberculosis and other infections since the 1940s, while kasugamycin is less known but crucial in agricultural settings to prevent bacterial diseases in crops.

Both antibiotics tamper with bacteria's ability to make new proteins by specifically targeting their ribosomes. These molecular structures create proteins and are themselves made of proteins and ribosomal RNA. Ribosomal RNA is often modified with chemical tags that can alter the shape and function of the ribosome. Cells use these tags to fine tune protein production.

The study found that, in response to the antibiotics, E. coli begins to assemble new ribosomes that are slightly different from the ones produced under normal conditions. Depending on which antibiotic is used, the new ribosomes lacked certain tags. The tags were specifically lost in the regions where antibiotics latch on to and halt protein production. The study found this made the bacteria more resistant to the drugs.

The researchers think the bacteria's ribosomes might be altering its structure just enough to prevent an antibiotic from binding effectively.

Bacteria are known to develop antibiotic resistance in different ways, including mutations in their DNA. Another common mechanism is their ability to actively pump and transport antibiotics out of the cell, reducing the concentration of the drug inside the cell to levels that are no longer harmful. The study is evidence of an entirely new survival strategy. E. coli is altering its molecular structures with remarkable precision and in real time. It's a stealthy and subtle way of dodging drugs.

The researchers made the findings using advanced nanopore sequencing technology, which read RNA molecules directly.

 Native RNA nanopore sequencing reveals antibiotic-induced loss of rRNA modifications in the A- and P-sites, Nature Communications (2024). DOI: 10.1038/s41467-024-54368-x

Comment by Dr. Krishna Kumari Challa on November 30, 2024 at 9:13am

Fine particulate air pollution may play a role in adverse birth outcomes

For pregnant women, exposure to fine particulate air pollution (PM2.5) was associated with altered immune responses that can lead to adverse birth outcomes, according to a new study. The study is the first to examine the relationship between PM2.5 and maternal and fetal health on a single-cell level and highlights the health risk of PM2.5 exposure for pregnant women.

The study is published in Science Advances. This study represents a substantial step forward in understanding the biological pathways through which PM2.5 exposure affects pregnancy, maternal health, and fetal development. Its advanced methodology represents a significant innovation for how we study immune responses to environmental exposures.

Previous research has found associations between exposure to PM2.5 and maternal and child health complications including preeclampsia, low birth weight, and developmental delays in early childhood. To understand these associations on a cellular level, the researchers used air quality data collected by the Environmental Protection Agency to calculate study participants' average PM2.5 exposure. Participants were both non-pregnant women and 20-week pregnant women.

The researchers then used an innovative technology to understand how pollution modified the DNA of participants' individual cells. Within each cell they were able to map changes to histones, the proteins that help control the release of cytokines—proteins that help control inflammation in the body and that can affect pregnancy.

The study found that PM2.5 exposure can influence the histone profiles of pregnant women, disrupting the normal balance of cytokine genes and leading to increased inflammation in both women and fetuses. In pregnant women, this increase in inflammation can correspond with adverse pregnancy outcomes.

These findings highlight the importance of minimizing air pollution exposure in pregnant women to protect maternal and fetal health.

Youn Soo Jung et al, Impact of air pollution exposure on cytokines and histone modification profiles at single-cell levels during pregnancy, Science Advances (2024). DOI: 10.1126/sciadv.adp5227. www.science.org/doi/10.1126/sciadv.adp5227

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