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Comment by Dr. Krishna Kumari Challa on July 23, 2023 at 11:34am

Very polite fish form queues in emergencies, new study finds

 Selfish humans push through one another to ensure their own survival – only to make everything worse. One very sensible species of fish forms queues to avoid exactly this issue, according to a new study.

When evacuating through narrow spaces, schools of neon tetra fish (Paracheirodon innesi) queue so that they don’t collide or clog up the line.

Researchers interpret this behaviour as respecting the social rules even in an emergency situation.  

Humans, like sheep, tend to quickly forget about social rules when they encounter a stressful situation, and rather adopt a selfish behaviour.

In the wild, neon tetra fish have to navigate around rocks in the rivers they swim along. To test how they do this when moving in large groups, a team of scientists from the University Grenoble Alpes, France, put the fish in a tank with narrow openings leading to other compartments.

These openings ranged in size from 1.5 to 4cm: not much bigger than the size of the fish themselves, which are 3cm long and 0.5cm wide.

The scientists then moved a fishing net through the tank and observed groups of 30 neon tetra fish as they evacuated through these openings.

The team were surprised to see that the fish gathered around the openings before passing through them – managing to avoid physical contact and clogging so that they could pass through at a constant rate.

The study marks the first time an experiment on crowd movements has focused on group evacuations in water. Previous observations have focused on animals that walk on 2D, solid surfaces.

https://www.nature.com/articles/s41598-023-36869-9?utm_medium=affil...

Comment by Dr. Krishna Kumari Challa on July 22, 2023 at 10:45am

This is an optical illusion.

The secret behind the confusing images is “reverse engineering”.

Devon, from 3D printing company Make Anything, proved that one side of each cylinder is shaped like a square and the other is more circular.

“Two of the sides are arching upwards, while the other two dip downwards and that basically ‘corrects’ this hybrid ‘squircle’ into either a square or a circle by compensating in opposite directions, which means it blends back into a square or circle when the true shape is right in between.

https://youtube.com/shorts/rVWQoGZeVOg?feature=share

Comment by Dr. Krishna Kumari Challa on July 22, 2023 at 10:36am

The role of ribosomes in the development of new treatments

The human body consists of trillions of cells, and 60% of the energy used within a cell is dedicated to a specific molecular machine. That machine is responsible for producing proteins, which are fundamental building blocks of the body.

The molecular machine is called a ribosome. The ribosome's task is to create proteins based on a copy of the genetic code found in the genome, known as mRNA. Until now, scientists thought that the ribosome performed the same type of work with all mRNA, like a standardized assembly line that it did not regulate on its own.

However, researchers now have discovered that this is not the case.

It has long been known that there are different types of ribosomes. But it has been assumed that no matter what mRNA you give the ribosome, it will produce a protein. But the new results suggest that different types of ribosomes produce specific proteins.

Scientists found that cancer cells have different ribosomes compared to other cells, and that was the basis for this new discovery. The paper based on this work is published in the journal Developmental Cell.

Part 1

Comment by Dr. Krishna Kumari Challa on July 22, 2023 at 10:26am

Using GPS as a possible earthquake predictor

A pair of seismologists  has found what might turn out to be an accurate way to predict earthquakes. In their study, reported in the journal Science, they looked at high-rate GPS time series data that was gathered in the time leading up to the moment earthquakes of magnitude 7 or above occurred. 

Seismologists have long sought to predict earthquakes so that people could react. In many cases, several minutes warning would be helpful—it would allow people to exit buildings that might collapse. Finding a precursor is difficult due to the lack of information regarding what was happening in the vicinity of an epicenter before a quake. In this new effort, they have found a way to go back in time to learn more about land shifting before a big quake.

In looking for an earthquake precursor, the researchers obtained and studied precise GPS data for geographical areas surrounding the epicenters of 90 quakes over magnitude 7 over the past several years. They found a pattern—a slip between tectonic plates that caused the land above them to move in a measurable, horizontal direction.

They also found that such slips could be observed and measured using GPS, that they occurred up to two hours before the earthquake struck and were too small to show up on standard seismographs. Most important, they saw the same slip in all the earthquakes they studied.

The work suggests that a reliable earthquake system could be designed based on a precise GPS listening system. On the downside,  researchers note that more work is required to prove that such a precursor exists for all, or at least most, large earthquakes. Also, they add, some upgrades to GPS technology are required to allow for measuring individual events around the clock.

 Quentin Bletery et al, The precursory phase of large earthquakes, Science (2023). DOI: 10.1126/science.adg2565

Roland Bürgmann, Reliable earthquake precursors?, Science (2023). DOI: 10.1126/science.adi8032

Comment by Dr. Krishna Kumari Challa on July 22, 2023 at 10:14am

Scientists develop AI-based tracking and early-warning system for viral pandemics

 Research scientists have developed a machine-learning system—a type of artificial intelligence (AI) application—that can track the detailed evolution of epidemic viruses and predict the emergence of viral variants with important new properties.

In a paper published in Patterns on July 21, 2023, the scientists demonstrated the system by using data on recorded SARS-CoV-2 variants and COVID-19 mortality rates. They showed that the system could have predicted the emergence of new SARS-CoV-2 "variants of concern" (VOCs) ahead of their official designations by the World Health Organization (WHO). Their findings point to the possibility of using such a system in real-time to track future viral pandemics.

The software enabled the researchers to track sets of genetic changes appearing in SARS-CoV-2 variants around the world. These changes—typically trending towards increased spread rates and decreased mortality rates—signified the virus' adaptations to lockdowns, mask wearing, vaccines, increasing natural immunity in the global population, and the relentless competition among SARS-CoV-2 variants themselves.

One of the big lessons of this work is that it is important to take into account not just a few prominent variants, but also the tens of thousands of other undesignated variants, which the scientists  call the 'variant dark matter.

A similar system could be used to track the detailed evolution of future viral pandemics in real time, the researchers note. In principle, it would enable scientists to predict changes in a pandemic's trajectory—for example, big increases in infection rates—in time to adopt appropriate public health countermeasures.

William E. Balch, Understanding the Host-Pathogen Evolutionary Balance through Gaussian Process Modelling of SARS-CoV-2, Patterns (2023). DOI: 10.1016/j.patter.2023.100800. www.cell.com/patterns/fulltext … 2666-3899(23)00155-1

Comment by Dr. Krishna Kumari Challa on July 21, 2023 at 2:04pm

The quirks of asp caterpillar venom support the idea it evolved independently from other insect venom, the researchers say. In fact, its origins seem to lie outside the animal kingdom entirely.

When researchers  looked at it more closely, they saw proteins that were very similar to some of the bacterial toxins that make people sick.

Specifically, asp caterpillar venom resembles a type of bacterial toxin that binds itself to the surface of a cell, the researchers explain, assembling into doughnut-like structures that rip holes in their cell target.

While organisms normally pass genes down their offspring in a so-called vertical fashion, sometimes genes can be transferred across between species – even distantly related ones – in a less common horizontal process.

Previous research has found evidence of horizontal gene transfer from bacteria to other, more complex creatures, including the transfer of genes involved with producing venom toxins.

In their new study, researchers say they've found evidence that major components of asp caterpillar venom were recruited as venom toxins from genes that bacteria transferred horizontally to their ancestors.

The venom in these caterpillars has evolved via the transfer of genes from bacteria more than 400 million years ago.

https://www.pnas.org/doi/10.1073/pnas.2305871120

Part 2

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Comment by Dr. Krishna Kumari Challa on July 21, 2023 at 2:01pm

Caterpillar Conceals a Venom Unlike Any Ever Seen in Insects

Caterpillars with a notoriously painful sting may have evolved their venom with help from ancient microbes, according to a new study  by scientists.

Their analysis has uncovered signs that a process known as horizontal gene transfer may have allowed sequences for toxins to jump from bacteria to the insect some time in their evolutionary past.

While the caterpillar's venom remains largely shrouded in mystery, researchers say its molecular secrets could turn out to be surprisingly beneficial for us.

The caterpillars wielding this venom are larvae of flannel moths (Megalopyge sp.); a soft, fuzzy genus native to North and South America. They're sometimes called "puss caterpillars," since their luxuriant coats of hairlike bristles can make them look sort of like caterpillar-sized cats.

But that's not their only nickname. Also known as "asp caterpillars," there's a hidden danger below those bristles.

The caterpillars' fur obscures an arsenal of venomous spines, which can inject powerful toxins into any would-be predators or hapless humans who touch them.

This venom causes an immediate and intense burning pain, commonly inspiring descriptions such as "being hit with a baseball bat," "walking on hot coals," or "the worst pain a patient has ever experienced," the researchers write.

part 1

Comment by Dr. Krishna Kumari Challa on July 21, 2023 at 12:02pm

A Cracked Piece of Metal Healed Itself in an Experiment!

 Scientists observed a metal healing itself, something never seen before. If this process can be fully understood and controlled, we could be at the start of a whole new era of engineering.

researchers were testing the resilience of the metal, using a specialized transmission electron microscope technique to pull the ends of the metal 200 times every second. They then observed the self-healing at ultra-small scales in a 40-nanometer-thick piece of platinum suspended in a vacuum.

Cracks caused by the kind of strain described above are known as fatigue damage: repeated stress and motion that causes microscopic breaks, eventually causing machines or structures to break. Amazingly, after about 40 minutes of observation, the crack in the platinum started to fuse back together and mend itself before starting again in a different direction.

Researchers have now confirmed  that metals have their own intrinsic, natural ability to heal themselves, at least in the case of fatigue damage at the nanoscale.

These are exact conditions, and we don't know yet exactly how this is happening or how we can use it. However, if you think about the costs and effort required for repairing everything from bridges to engines to phones, there's no telling how much difference self-healing metals could make.

And while the observation is unprecedented, it's not wholly unexpected. In 2013, materials scientists  worked on a study predicting that this kind of nanocrack healing could happen, driven by the tiny crystalline grains inside metals essentially shifting their boundaries in response to stress.

That the automatic mending process happened at room temperature is another promising aspect of the research. Metal usually requires lots of heat to shift its form, but the experiment was carried out in a vacuum; it remains to be seen whether the same process will happen in conventional metals in a typical environment.

A possible explanation involves a process known as cold welding, which occurs under ambient temperatures whenever metal surfaces come close enough together for their respective atoms to tangle together. Typically, thin layers of air or contaminants interfere with the process; in environments like the vacuum of space, pure metals can be forced close enough together to literally stick.

https://www.nature.com/articles/s41586-023-06223-0

Comment by Dr. Krishna Kumari Challa on July 21, 2023 at 10:56am

The First Dark Stars
At least three far-off objects observed by the James Webb Space Telescope (JWST) could be stellar objects called “dark stars.” These stars might not be fueled by nuclear fusion but by the self-annihilation of dark matter—the invisible stuff that is thought to make up about 85 percent of the matter in the universe. Dark stars could have formed soon after the big bang, from the collapse of helium and hydrogen clouds that annihilated the particles within.
Dark stars have never been definitively observed before–astronomers weren’t even sure they really existed. To prove these objects are indeed dark stars will take many months of observation–particularly, watching their electromagnetic spectrums for a particular isotope of helium only found in dark stars, not in galaxies.
“Finding a dark star would not only provide a new look into the early formation of the universe,” says Pearl Sandick, a theoretical particle physicist at the University of Utah, “but would also be a unique opportunity to directly observe dark matter interactions.
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In 2007, scientists proposed the idea of Dark Stars. The first phase of stellar evolution in the history of the universe may be Dark Stars (DS), powered by dark matter (DM) heating rather than by nuclear fusion. Although made almost entirely of hydrogen and helium from the Big Bang, they form at the centers of protogalaxies where there is a sufficient abundance of DM to serve as their heat source. They are very bright diffuse puffy objects and grow to be very massive. In fact, they can grow up to ten million solar masses with up to ten billion solar luminosities. In this paper, they show that the James Webb Space Telescope may have already discovered these objects.

https://www.pnas.org/doi/full/10.1073/pnas.2305762120

Comment by Dr. Krishna Kumari Challa on July 21, 2023 at 8:44am

Study shows how the brain coordinates neuronal processing and communication during sleep

Past neuroscience studies have shown that while humans are sleeping, the brain remains highly active, consolidating memories and removing toxins accumulated during waking hours. While memory consolidation during sleep is a widely documented phenomenon, the processes underpinning it are yet to be fully elucidated.

Researchers recently carried out a study investigating the neural mechanisms through which the brain facilitates neuronal processing and communication between neurons during sleep. Their paper, published in Nature Neuroscience, unveils the processes through which the sequential unfolding of specific sleep rhythms coordinates memory consolidation while humans are asleep.

A few years ago, scientists found that some of the key sleep signatures ('slow oscillations,' 'spindles' and 'ripples') coincide in the hippocampus, the brain's 'memory hub.' This was a good indication that the synchronization of these sleep rhythms may be involved in memory consolidation. What was missing, however, was evidence that they in fact impact neuronal firing rates, i.e., the 'hard currency' of learning and plasticity.

Scientists now recorded the brain activity of 10 human participants as they were asleep using a technique known as intracranial electroencephalography (iEEG). These participants were patients with epilepsy who had electrodes implanted in their brain as part of their treatment.

While the patients were sleeping, Staresina and his colleagues simultaneously recorded their sleep rhythms and neuron firing rates. The recordings they collected showed that firing rates and neural communication are indeed orchestrated by slow oscillations, spindles and ripples, as they hypothesized.

Bernhard P. Staresina et al, How coupled slow oscillations, spindles and ripples coordinate neuronal processing and communication during human sleep, Nature Neuroscience (2023). DOI: 10.1038/s41593-023-01381-w

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