Comment

Comment by Dr. Krishna Kumari Challa on October 17, 2023 at 10:46am

Why a spinning magnet can cause a second magnet to levitate

A team of physicists has found the reason a spinning magnet can cause a secondary magnet to levitate without the need for stabilization. In their paper published in the journal Physical Review Applied, the group describes experiments they conducted to learn more about the phenomenon and what they learned from them.

Prior research and anecdotal evidence have shown that if two magnets with north poles facing one another are brought close together, they will repel one another. Such force has been used for applications such as levitating trains. But these applications must account for the inherent instability that arises when magnets repel each other. More recently, scientists have found that if one of the magnets is spun at high speed, a second magnet can be repelled without the need for stabilizing—it remains levitated even when the first magnet is moved around. In this new effort, the researchers have uncovered the reason for such behavior. To learn more about the phenomenon, the research team paired several different types of magnets and spun them at different speeds while recording the action with high-speed cameras and motion tracking software. In studying the resulting imagery, the team was able to uncover the reason for the behavior.

Part 1

Comment by Dr. Krishna Kumari Challa on October 17, 2023 at 8:26am

The universe generates novel combinations of atoms, molecules, cells, etc. Those combinations that are stable and can go on to engender even more novelty will continue to evolve. This is what makes life the most striking example of evolution, but evolution is everywhere."

Among many implications, the paper offers:

1. Understanding into how differing systems possess varying degrees to which they can continue to evolve. "Potential complexity" or "future complexity" have been proposed as metrics of how much more complex an evolving system might become
2. Insights into how the rate of evolution of some systems can be influenced artificially. The notion of functional information suggests that the rate of evolution in a system might be increased in at least three ways: (1) by increasing the number and/or diversity of interacting agents, (2) by increasing the number of different configurations of the system; and/or (3) by enhancing the selective pressure on the system (for example, in chemical systems by more frequent cycles of heating/cooling or wetting/drying).
3. A deeper understanding of generative forces behind the creation and existence of complex phenomena in the universe, and the role of information in describing them
4. An understanding of life in the context of other complex evolving systems. Life shares certain conceptual equivalencies with other complex evolving systems, but the authors point to a future research direction, asking if there is something distinct about how life processes information on functionality (see also https://royalsocietypublishing.org/doi/10.1098/rsif.2022.0810).
5. Aiding the search for life elsewhere: if there is a demarcation between life and non-life that has to do with selection for function, can we identify the "rules of life" that allow us to discriminate that biotic dividing line in astrobiological investigations? (See also "Did Life Exist on Mars? Other Planets? With AI's Help, We May Know ...")
6. At a time when evolving AI systems are an increasing concern, a predictive law of information that characterizes how both natural and symbolic systems evolve is especially welcome

Laws of nature—motion, gravity, electromagnetism, thermodynamics—etc. codify the general behavior of various macroscopic natural systems across space and time.

The "law of increasing functional information" complements the 2nd law of thermodynamics, which states that the entropy (disorder) of an isolated system increases over time (and heat always flows from hotter to colder objects).

On the roles of function and selection in evolving systems, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2310223120. doi.org/10.1073/pnas.2310223120

Part 4

Comment by Dr. Krishna Kumari Challa on October 17, 2023 at 8:26am

Life's evolutionary history is rich with novelties—photosynthesis evolved when single cells learned to harness light energy, multicellular life  evolved when cells learned to cooperate, and species evolved thanks to advantageous new behaviors such as swimming, walking, flying, and thinking.

The same sort of evolution happens in the mineral kingdom. The earliest minerals represent particularly stable arrangements of atoms. Those primordial minerals provided foundations for the next generations of minerals, which participated in life's origins. The evolution of life and minerals are intertwined, as life uses minerals for shells, teeth, and bones.

Indeed, Earth's minerals, which began with about 20 at the dawn of our solar system, now number almost 6,000 known today thanks to ever more complex physical, chemical, and ultimately biological processes over 4.5 billion years.

In the case of stars, the paper notes that just two major elements—hydrogen and helium—formed the first stars shortly after the big bang. Those earliest stars used hydrogen and helium to make about 20 heavier chemical elements. And the next generation of stars built on that diversity to produce almost 100 more elements.

Part 3

Comment by Dr. Krishna Kumari Challa on October 17, 2023 at 8:24am

Regardless of whether the system is living or nonliving, when a novel configuration works well and function improves, evolution occurs.

The authors' "Law of Increasing Functional Information" states that the system will evolve "if many different configurations of the system undergo selection for one or more functions."

In the case of biology, Darwin equated function primarily with survival—the ability to live long enough to produce fertile offspring.

The new study expands that perspective, noting that at least three kinds of function occur in nature.

The most basic function is stability—stable arrangements of atoms or molecules are selected to continue. Also chosen to persist are dynamic systems with ongoing supplies of energy.

The third and most interesting function is "novelty"—the tendency of evolving systems to explore new configurations that sometimes lead to startling new behaviors or characteristics.

Part 2

Comment by Dr. Krishna Kumari Challa on October 17, 2023 at 8:22am

Scientists identify nature's missing evolutionary law

A paper published in the Proceedings of the National Academy of Sciences describes "a missing law of nature," recognizing for the first time an important norm within the natural world's workings.

In essence, the new law states that complex natural systems evolve to states of greater patterning, diversity, and complexity. In other words, evolution is not limited to life on Earth, it also occurs in other massively complex systems, from planets and stars to atoms, minerals, and more.

"Macroscopic" laws of nature describe and explain phenomena experienced daily in the natural world. Natural laws related to forces and motion, gravity, electromagnetism, and energy, for example, were described more than 150 years ago.

The new work presents a modern addition—a macroscopic law recognizing evolution as a common feature of the natural world's complex systems, which are characterized as follows:

• They are formed from many different components, such as atoms, molecules, or cells, that can be arranged and rearranged repeatedly
• Are subject to natural processes that cause countless different arrangements to be formed
• Only a small fraction of all these configurations survive in a process called "selection for function."

Part 1

Comment by Dr. Krishna Kumari Challa on October 16, 2023 at 9:54am

A theory on how gold, platinum, and other precious metals found their way into Earth's mantle

Scientists say they've hit the jackpot with some valuable new information about the story of gold.

It's a story that begins with violent collisions of large objects in space, continues in a half-melted region of Earth's mantle, and ends with precious metals finding an unlikely resting spot much closer to the planet's surface than scientists would have predicted.

Their new theory provides possible answers to lingering questions about the way gold, platinum, and other precious metals found their way to shallow pockets within Earth's mantle rather than deep in the planet's core. More broadly, the new theory offers insights into planet formation throughout the universe.

Recent research from scientists around the world has established that precious metals such as gold and platinum came to Earth billions of years ago after the early proto-Earth collided with large, moon-sized bodies in space, which left behind deposits of materials that were folded into what is today's Earth.

Aside from being valued for their scarcity, aesthetic beauty, and use in high-tech products, gold and platinum are what is known as highly "siderophile" elements. They are drawn to the element iron to such a degree that they would be expected to collect almost entirely in Earth's metallic core—either by merging directly with the metal core on impact or by sinking quickly from the mantle into the core.

By this logic, they should not have collected at or near the Earth's surface. Yet they did.

The new theory centers around a thin, "transient" region of the mantle, where the shallow part of the mantle melts and the deeper part remains solid. The researchers found that this region has peculiar dynamic properties that can efficiently trap falling metallic components and slowly deliver them to the rest of the mantle. 

Their theory posits that this delivery is still ongoing, with the remnants of the transient region appearing as "large low-shear-velocity provinces"—well-known geophysical anomalies in the deep mantle.

This transient region almost always forms when a big impactor hits the early Earth, making this new  theory quite robust.

 Jun Korenaga et al, Vestiges of impact-driven three-phase mixing in the chemistry and structure of Earth's mantle, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2309181120

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Comment by Dr. Krishna Kumari Challa on October 16, 2023 at 8:50am

If you are not getting enough sleep, your vascular cells may be drowning in oxidants!

Several people in the world are in the same situation of sleep deprivation and habitually get only five to six hours of sleep instead of the recommended seven to eight hours.

But even a mild chronic sleep deficit may heighten the risk of developing heart disease later in life: Surveys of thousands of people have found that people who report mild but chronic sleep deficits have more heart disease later in life than people who get adequate sleep.

Published in Scientific Reports, a study of women now shows what's happening in the body during chronic mild sleep deprivation.

After just six weeks of shortened sleep, the study found, the cells that line our blood vessels are flooded by damaging oxidants. And unlike well-rested cells, sleep-restricted cells fail to activate antioxidant responses to clear the destructive molecules.

The result: cells that are inflamed and dysfunctional, an early step in the development of cardiovascular disease. This is some of the first direct evidence to show that mild chronic sleep deficits cause heart disease.

Riddhi Shah, Vikash Kumar Shah, Memet Emin, Su Gao, Rosemary V. Sampogna, Brooke Aggarwal, Audrey Chang, Marie-Pierre St-Onge, Vikas Malik, Jianlong Wang, Ying Wei, Sanja Jelic. Mild sleep restriction increases endothelial oxidative stress in female persons. Scientific Reports, 2023; 13 (1) DOI: 10.1038/s41598-023-42758-y

Comment by Dr. Krishna Kumari Challa on October 15, 2023 at 6:32am

Flu-resistant chickens
 Birds with small alterations to one gene are highly resistant to avian flu

Scientists have created the world’s first flu-resistant chickens in an advance that could pave the way for gene-edited poultry. The birds, which had small alterations to one gene, were highly resistant to avian flu, with nine in 10 birds showing no signs of infection when exposed to a typical dose of the virus.

However, infections were not completely blocked, and scientists say this would have to be achieved before genetically engineered chickens could be introduced to farms, due to the risk of the virus evolving to become more dangerous to humans.

https://www.nature.com/articles/s41467-023-41476-3

Comment by Dr. Krishna Kumari Challa on October 14, 2023 at 8:37am

The three types of households with their typical characteristics and food waste behaviours. Credit: Trang Nguyen using Canva.com, CC BY-NC-ND

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 a fire retardant in building materials

Comment by Dr. Krishna Kumari Challa on October 14, 2023 at 8:20am

Targeting a coronavirus ion channel could yield new COVID-19 drugs

The genome of the SARS-CoV-2 virus encodes 29 proteins, one of which is an ion channel called E. This channel, which transports protons and calcium ions, induces infected cells to launch an inflammatory response that damages tissues and contributes to the symptoms of COVID-19.

MIT chemists have now discovered the structure of the "open" state of this channel, which allows ions to flow through. This structure, combined with the "closed" state structure that was reported by the same lab in 2020, could help scientists figure out what triggers the channel to open and close. These structures could also guide researchers in developing antiviral drugs that block the channel and help prevent inflammation.

When SARS-CoV-2 infects cells, the E channel embeds itself inside the membrane that surrounds a cellular organelle called the ER-Golgi intermediate compartment (ERGIC). The ERGIC interior has a high concentration of protons and calcium ions, which the E channel transports out of ERGIC and into the cell cytoplasm. That influx of protons and calcium leads to the formation of multiprotein complexes called inflammasomes, which induce inflammation.

Previous research has shown that when SARS-CoV-2 viruses are mutated so that they don't produce the E channel, the viruses generate much less inflammation and cause less damage to host cells.

So the E channel is an antiviral drug target now. If you can stop the channel from sending calcium into the cytoplasm, then you have a way to reduce the cytotoxic effects of the virus.

Joao Medeiros-Silva et al, Atomic Structure of the Open SARS-CoV-2 E Viroporin, Science Advances (2023). DOI: 10.1126/sciadv.adi9007. www.science.org/doi/10.1126/sciadv.adi9007

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