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Comment by Dr. Krishna Kumari Challa on February 7, 2024 at 8:49am

Scientists Transformed Pure Water Into a Metal

Water found in nature conducts electricity – but that's because of the impurities therein, which dissolve into free ions that allow an electric current to flow. Pure water only becomes "metallic" – electronically conductive – at extremely high pressures, beyond our current abilities to produce in a lab.

But, as researchers demonstrated for the first time back in 2021, it's not only high pressures that can induce this metallicity in pure water.

By bringing pure water into contact with an electron-sharing alkali metal – in this case an alloy of sodium and potassium – free-moving charged particles can be added, turning water metallic.

The resulting conductivity only lasts a few seconds, but it's a significant step towards being able to understand this phase of water by studying it directly.

You can see the phase transition to metallic water with the naked eye! The silvery sodium-potassium droplet covers itself with a golden glow, which is very impressive.

Metallic water prepared for first time under terrestrial conditions

The idea is that if you squeeze the atoms together tightly enough, the orbitals of the outer electrons would start to overlap, allowing them to move around. For water, this pressure is around 48 megabars – just under 48 million times Earth's atmospheric pressure at sea level.

While pressures exceeding this have been generated in a laboratory setting, such experiments would be unsuitable for studying metallic water. So a team of researchers turned to alkali metals.

These substances release their outer electrons very easily, which means they could induce the electron-sharing properties of highly pressurized pure water without the high pressures.

Part 1

Comment by Dr. Krishna Kumari Challa on February 7, 2024 at 8:35am

However, the elasticity of the flagellum doesn’t fully explain how the cell is able to move, which is where odd elasticity comes in. This allows the cells to wiggle their flagella without expending much energy to their surroundings, which would otherwise suppress their motility. 

The higher a cell’s odd elasticity score (or odd elastic modulus), the more able a flagellum is to wave sans large energy loss, and so the cell is better able to move forward – in a way that defies physics.

Sperm and algae are not the only cells in possession of a flagellum – many microorganisms have one (they can make bacteria sound like they’re playing tiny drums)  – which means there are likely other rule-breakers out there to be discovered. Being able to understand and classify other cells or organisms capable of non-reciprocal movement could be very useful, the team behind the study told New Scientist.

Their approach could even help in the design of small elastic robots with the ability to break Newton’s third law, according to one of the study's authors, Kenta Ishimoto of Kyoto University in Japan.

Moreover, the odd elastic modulus can be calculated for any closed-loop system, meaning it could be applied to a wide range of biological data, including active elastic membranes and bulk dynamics, the authors explain in their conclusion.

Breaking the law has never been so beneficial.

The study is published in PRX Life.

https://journals.aps.org/prxlife/abstract/10.1103/PRXLife.1.023002

https://www.iflscience.com/sperm-caught-breaking-the-law-newtons-th...

Part 2

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Comment by Dr. Krishna Kumari Challa on February 7, 2024 at 8:33am

Sperm caught breaking Newton's third law of motion

Some biological cells swim freely in a way that apparently breaks one of Newton’s laws of motion – but only if they have strange elastic properties

HUMAN sperm cells and some microorganisms swim by deforming their bodies in a way that breaks Isaac Newton's third law of motion - and we are closer to understanding how they do it. The findings could inspire tiny swimming robots that also violate this law.

he laws of physics have been broken (or appear to have been broken) by all manner of things, from balancing rocks to Seinfeld’s apartment, and now, by human sperm. The latest law-breakers defy Newton's third law of motion, distorting their bodies as they swim in a way that elicits no response from their surroundings.

Newton's third law states that when one object exerts a force on a second object, the second object exerts an equal and opposite force back. In other words, “for every action, there is an equal and opposite reaction”. However, for biological swimmers such as sperm, this may not be the case.

In a new study, scientists analyzed Chlamydomonas algae and data on human sperm cells, identifying non-reciprocal mechanical interactions, which they call “odd elasticity”, that go against Newton’s third law.

Both Chlamydomonas and sperm cells use hair-like appendages called flagella to move around. These protrude from the cell, almost like a tail, helping to propel it forward by changing shape as they interact with the surrounding fluid. They do so in a non-reciprocal way, meaning they don’t provoke an equal and opposite response from their surroundings and therefore, flout Newton’s third law.

Part 1

Comment by Dr. Krishna Kumari Challa on February 7, 2024 at 6:26am

Looking into the possibility of volcanic lightning being the spark that ignited life on Earth

An international team of geologists, Earth scientists and mineralogists has found evidence suggesting that volcanic lightning may have fixed huge amounts of atmospheric nitrogen, allowing life on Earth to get its start.

In their study, published in the Proceedings of the National Academy of Sciences, the group collected and analyzed ancient volcanic deposits to learn more about how ancient eruptions may have produced nitrates that could have been used to create amino acids.

Prior research has shown that the development of life required fixing nitrogen, a key component of amino acids, during Earth's early years. In modern times, there is plenty of nitrogen in the atmosphere but plants cannot use it directly; it must first be fixed by bacteria that can convert it to nitrates or other nitrogen compounds.

That raises the question of how bacteria and then other life forms originated. In this new study, the researchers found evidence that nitrogen in the atmosphere could have been fixed by volcanic lightning interacting with ash.

Prior research has shown that lightning, whether due to thunderstorms or volcanic eruptions, can lead to the formation of nitrates under the right conditions. Lighting from thunderstorms has been ruled out as a candidate for production of the nitrates that led to the beginning of life due to the limited amounts that are produced.

To find out if the same held true for lightning produced during volcanic eruptions, the research team ventured to sites in Turkey, Italy and Peru, known to host ancient volcanic deposits. Samples from these sites contained large amounts of nitrates. Testing showed that they were atmospheric and had not come directly from the volcano—that left lightning as their likely source. But the thing that truly bolstered their theory was the huge amounts of nitrates they found, which were more than enough to serve as a source for creating amino acids.
The team notes that prior research efforts have led to theories that life began near volcanoes—and one team even found some evidence that suggested volcanic lightning interacting with volcanic gases could produce molecules used by living things, such as amino acids.

Adeline Aroskay et al, Geological evidence of extensive N-fixation by volcanic lightning during very large explosive eruptions, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2309131121

Comment by Dr. Krishna Kumari Challa on February 7, 2024 at 6:21am

Healthy living builds 'cognitive reserve' in brain that may prevent dementia

New research suggests healthy lifestyles can help stave off dementia, perhaps by building a resilient 'cognitive reserve' in the aging brain.

The study was based on the brain autopsies on 586 people who lived to an average age of almost 91. Researchers compared each person's lifestyle and end-of-life mental skills to their neurological signs of dementia, such as brain protein plaques or changes in brain blood flow.

None of these brain factors seemed to greatly affect the positive connection between healthy living and a person's end-of-live mental skills.

That means that good nutrition, regular exercise and other factors may instead "provide a cognitive reserve" that buffers against negative changes going on within the brain—allowing older folk to "maintain cognitive abilities" over time, the researchers said.

You can almost sort of cheat the biology a little bit and still not get the symptomatology as early.

There's more on the interplay between lifestyle and brain health at the U.S. Center for Disease Control and Prevention.

Klodian Dhana et al, Healthy Lifestyle and Cognition in Older Adults With Common Neuropathologies of Dementia, JAMA Neurology (2024). DOI: 10.1001/jamaneurol.2023.5491

Comment by Dr. Krishna Kumari Challa on February 7, 2024 at 6:10am

Amazing things can happen with science and technology: AI reads ancient scroll burnt and  buried by Vesuvius eruption!

Three researchers on Monday won a $700,000 prize for using artificial intelligence to read a 2,000-year-old scroll that was scorched in the eruption of Mount Vesuvius.
The Herculaneum papyri consist of about 800 rolled up Greek scrolls that were carbonized during the 79 CE volcanic eruption that buried the ancient Roman town of Pompeii, according to the organizers of the "Vesuvius Challenge."

Resembling logs of hardened ash, the scrolls, which are kept at Institut de France in Paris and the National Library of Naples, have been extensively damaged and even crumbled when attempts have been made to roll them open.

As an alternative, the Vesuvius Challenge carried out high-resolution CT scans of four scrolls and offered one million dollars spread out among multiple prizes to spur research on them.

The trio who won the prize was composed of Youssef Nader, a Ph.D. student in Berlin, Luke Farritor, a student and SpaceX intern from Nebraska, and Julian Schilliger, a Swiss robotics student.

The group used AI to help distinguish ink from papyrus and work out the faint and almost unreadable Greek lettering through pattern recognition.
Three researchers on Monday won a $700,000 prize for using artificial intelligence to read a 2,000-year-old scroll that was scorched in the eruption of Mount Vesuvius.

The Herculaneum papyri consist of about 800 rolled up Greek scrolls that were carbonized during the 79 CE volcanic eruption that buried the ancient Roman town of Pompeii, according to the organizers of the "Vesuvius Challenge."

Resembling logs of hardened ash, the scrolls, which are kept at Institut de France in Paris and the National Library of Naples, have been extensively damaged and even crumbled when attempts have been made to roll them open.

As an alternative, the Vesuvius Challenge carried out high-resolution CT scans of four scrolls and offered one million dollars spread out among multiple prizes to spur research on them.

The trio who won the prize was composed of Youssef Nader, a Ph.D. student in Berlin, Luke Farritor, a student and SpaceX intern from Nebraska, and Julian Schilliger, a Swiss robotics student.

The group used AI to help distinguish ink from papyrus and work out the faint and almost unreadable Greek lettering through pattern recognition.
Last year Farritor decoded the first word from one of the scrolls, which turned out to be the Greek word for "purple."

Jointly, their efforts have now decrypted about five percent of the scroll, according to the organizers.

The scroll's author was "probably Epicurean philosopher Philodemus," writing "about music, food, and how to enjoy life's pleasures," wrote contest organizer Nat Friedman on X.
The scrolls were found in a villa thought to be previously owned by Julius Caesar's patrician father-in-law, whose mostly unexcavated property held a library that could contain thousands more manuscripts.
The recovery of never-seen ancient texts would be a huge breakthrough.
The next phase of the competition will attempt to leverage the research to unlock 85 percent of the scroll
Source: AFP and other news agencies

Comment by Dr. Krishna Kumari Challa on February 6, 2024 at 1:11pm

Study finds new treatment to reverse inflammation and arterial blockages in rheumatoid arthritis

Researchers  have found that the molecule RvT4 enhances the body's natural defenses against atherosclerosis (hardening of the arteries) in patients with rheumatoid arthritis.

Studies in mice undertaken by researchers  show that increasing levels of the RvT4 molecule in the body improves the ability of the body's own defense mechanisms (macrophages) to reduce local inflammation and remove blockages in blood vessels. This breakthrough in understanding the processes involved could lead to better treatments for people who have rheumatoid arthritis (RA), and who are at higher risk of developing cardiovascular disease.

Alongside the more widely-known symptoms of joint inflammation, people with the condition are also twice as likely as others to develop blood vessel disease. This can lead to serious complications and an increased risk of premature death.

One type of blood vessel disease seen in people with RA is atherosclerosis, which is caused by a build-up of fatty material called 'plaque' along the artery walls. This build-up causes the arteries to harden and narrow, making it more difficult to circulate blood around the body. These blockages can also break free, causing heart attacks and strokes. Understanding the reasons why RA patients are at increased risk of these cardiovascular problems is critical in developing better treatments for this group and others.

To gain a better understanding of the causes of blood vessel disease in patients with RA, researchers explored the role of a group of molecules called 13-series resolvins (RvTs). In experimental arthritis the levels of one of these molecules, RvT4, are markedly reduced, a phenomenon that associates with a higher degree of blood vessel disease. This study was designed to explore why this might be the case.

Published in Nature Communications, the study found that treating arthritic mice with RvT4 reduced blood vessel inflammation by re-programming macrophages—a group of white blood cells that accumulate in the diseased vessels—to release stored lipids.

Researchers observed that these lipids were preventing the macrophage from carrying out their usual work of clearing dead cells and reducing localized inflammation in blood vessels. Once freed of their lipid burden, the macrophages were able to move and work much more effectively to reduce the causes of atherosclerosis. The observation that RvT4 restores protective macrophage biological activities is an exciting finding.

Resolvin T4 enhances macrophage cholesterol efflux to reduce vascular disease, Nature Communications (2024). DOI: 10.1038/s41467-024-44868-1

Comment by Dr. Krishna Kumari Challa on February 6, 2024 at 1:06pm

Alzheimer's may have once spread from person to person, but the risk of that happening today is incredibly low

An article published this week in the journal Nature Medicine documents what is believed to be the first evidence that Alzheimer's disease can be transmitted from person to person.

The finding arose from long-term follow up of patients who received human growth hormone (hGH) that was taken from brain tissue of deceased donors. Preparations of donated hGH were used in medicine to treat a variety of conditions from 1959 onwards.

The practice stopped in 1985 when it was discovered around 200 patients worldwide who had received these donations went on to develop Creuztfeldt-Jakob disease (CJD), which causes a rapidly progressive dementia. This is an otherwise extremely rare condition, affecting roughly one person in a million.

CJD is caused by prions: infective particles that are neither bacterial or viral, but consist of abnormally folded proteins that can be transmitted from cell to cell. Other prion diseases include kuru, a dementia seen in New Guinea tribespeople caused by eating human tissue, scrapie (a disease of sheep) and variant CJD or bovine spongiform encephalopathy, otherwise known as mad cow disease. This raised public health concerns over the eating of beef products in the United Kingdom in the 1980s.

Human growth hormone (hGH) is produced in the brain by the pituitary gland. Treatments were originally prepared from purified human pituitary tissue. But because the amount of hGH contained in a single gland is extremely small, any single dose given to any one patient could contain material from around 16,000 donated glands. An average course of hGH treatment lasts around four years, so the chances of receiving contaminated material—even for a very rare condition such as CJD—became quite high for such people. hGH is now manufactured synthetically in a laboratory, rather than from human tissue. So this particular mode of CJD transmission is no longer a risk.

Gargi Banerjee et al, Iatrogenic Alzheimer's disease in recipients of cadaveric pituitary-derived growth hormone, Nature Medicine (2024). DOI: 10.1038/s41591-023-02729-2

Comment by Dr. Krishna Kumari Challa on February 6, 2024 at 12:48pm

The reason insects fly around light

Comment by Dr. Krishna Kumari Challa on February 6, 2024 at 12:44pm

The reason insects circle lights at night: They lose track of the sky

It's an observation as old as humans gathering around campfires: Light at night can draw an erratically circling crowd of insects. In art, music and literature, this spectacle is an enduring metaphor for dangerous but irresistible attractions. And watching their frenetic movements really gives the sense that something is wrong—that instead of finding food and evading predators, these nocturnal pilots are trapped by a light.

Sadly, centuries of witnessing what happens have produced little certainty about why it happens. How does a simple light change fast, precise navigators into helpless, flittering captives? We are researchers examining flight, vision and evolution, and we have used high-speed tracking techniques in research published in Nature Communications to provide an answer.

Samuel T. Fabian et al, Why flying insects gather at artificial light, Nature Communications (2024). DOI: 10.1038/s41467-024-44785-3

https://theconversation.com/the-surprising-reason-why-insects-circl...

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