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Comment by Dr. Krishna Kumari Challa on July 30, 2024 at 9:52am

 Chimpanzees  are capable of speech

Axel G. Ekström et al, Chimpanzee utterances refute purported missing links for novel vocalizations and syllabic speech, Scientific Reports (2024). DOI: 10.1038/s41598-024-67005-w

Comment by Dr. Krishna Kumari Challa on July 30, 2024 at 9:05am

This can result in the wave either delivering its energy to the particles or gaining energy from them, causing the particles to either damp or grow.
This new research work finds that KAWs rapidly dissipate, completely transferring their energy to plasma particles in the form of heating. This energy transfer accelerates the particles over longer spatial distances, significantly impacting the dynamics of the plasma.
The analytical insights gleaned from this study will find practical application in understanding phenomena within the solar atmosphere, particularly shedding light on the significant role played by non-thermal particles in the heating processes.

 Syed Ayaz et al, Solar Coronal Heating by Kinetic Alfvén Waves, The Astrophysical Journal (2024). DOI: 10.3847/1538-4357/ad5bdc

Part 3

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Comment by Dr. Krishna Kumari Challa on July 30, 2024 at 9:04am

The researchers focused on the heating and energy exchange facilitated by KAWs. The reason for the great interest in these waves lies in their ability to transport energy. Observational data from numerous spacecraft and theoretical investigations have consistently demonstrated that KAWs dissipate and contribute to solar coronal heating during their propagation in space.
Because of these unique properties, the waves provide a critical mechanism for transferring energy, important to understanding the energy exchange between electromagnetic fields and plasma particles.
KAWs operate on small kinetic scales and are capable of supporting parallel electric and magnetic field fluctuations, enabling an energy transfer between the wave field and plasma particles through a phenomenon called Landau interactions.
The present work utilized and explores the Landau damping mechanism, which occurs when particles moving parallel to a wave have velocities comparable to the wave's phase velocity.
Landau damping is an exponential decrease as a function of time of particular waves in plasma. "When particles interact with the wave, they receive/lose energy—a term called 'resonant condition.
Part 2

Comment by Dr. Krishna Kumari Challa on July 30, 2024 at 9:02am

Why the solar corona is so much hotter than sun's surface

In a new study published in The Astrophysical Journal,  researchers explore critical aspects of a phenomenon called kinetic Alfvén waves (KAWs) to provide fresh insights into an age-old heliophysics mystery.

They examined the potentially pivotal role of KAWs in heating the solar corona, moving science one step closer to solving the puzzle of why the corona is many times hotter than the surface of the sun itself.

For decades, Alfvén waves have been proven to be the best candidates for transporting energy from one place to another. 

This paper utilizes a novel approach to model energetic particles in space plasmas, as observed by satellites like Viking and Freja, to answer how the electromagnetic energy of the waves, interacting with particles, transforms into heat during the damping process as the waves move through space.

The corona, or solar atmosphere, is an enigmatic region surrounding our home star that extends far beyond the visible disk of the sun, stretching some 8 million kilometers above the sun's surface. Yet, the corona is also characterized by extraordinarily high temperatures, a mystery that has captivated astrophysicists for nearly seventy years.

This new work  offers important insights into the critical problem of how energy in a magnetic field is transformed to heat a plasma comprising charged particles like protons and electrons.

Kinetic Alfvén waves—abundant throughout the plasma universe—are oscillations of the ions and magnetic field as they move through the solar plasma. The waves are formed by motions in the photosphere, the sun's outer shell that radiates visible light.

Part 1

Comment by Dr. Krishna Kumari Challa on July 30, 2024 at 8:43am

Don't close your borders: Countries need to cooperate on migration as climate crisis worsens

Humanity must rethink migration as the climate crisis drives rapid global changes, researchers say.

With significant migration expected—and border policies hardening—the researchers say the "time is ripe to highlight the benefits of collaboration between nations and regions."

By promoting the benefits of migration, especially in an era of aging populations, global leaders could ensure a better future for people and societies.

The paper, titled "Anticipating the global redistribution of people and property" and published in the journal One Earth, comes from an international team of climate and social scientists. 

Millions of people are projected to be displaced by sea-level rise in the next decades, and 2 billion could be exposed to extreme heat beyond their experience by the end of the century.

Ignoring or downplaying the inevitable global redistribution of people would lead to geo-political instability, and a polarized and fractured world.

"Instead, the international community must come together to rethink mobility and cultural integration to ensure a benign transition to this new world."

So far, most migration with significant climate dimensions has happened within countries, with people leaving areas affected by long-term decline in agricultural productivity or escaping conditions such as coastal erosion or extreme events.

While some large nations have different climate zones that can accommodate this, small countries do not.

The paper also warns that a "skewed distribution of wealth and associated power" makes it difficult for people to move, both within and between states.

Global warming exacerbates existing inequalities, making habitability a major political challenge of this century.

"Concrete cooperation is now needed to match migrant flows with demand for labor, to the benefit of the Global South and the developed world alike.

The paper says major reform of the food system, supported by movement of workers, could increase production while conserving nature.

Migration can therefore be a win–win for people and the climate, but leaders must make a positive case for economic benefits and effective integration. "Playing up the social costs of migration appeals to national identity motivations, but fails to overcome problems from aging populations.

Instead, leaders should focus on the economic and social benefits of new populations and effective integration, which benefits newcomers and original inhabitants alike.

"Every corner of the world needs to anticipate the coming climate crisis and promote the safe and beneficial movement of people as conditions change.

It is the question of survival and you can't stop people from moving when their very existence is under threat. 

Marten Scheffer et al, Anticipating the global redistribution of people and property, One Earth (2024). DOI: 10.1016/j.oneear.2024.06.008

You 

Comment by Dr. Krishna Kumari Challa on July 30, 2024 at 8:29am

Origins of matter in the early universe

The early universe was 250,000 times hotter than the core of our sun. That's far too hot to form the protons and neutrons that make up everyday matter. Scientists recreate the conditions of the early universe in particle accelerators by smashing atoms together at nearly the speed of light.

Measuring the resulting shower of particles allows scientists to understand how matter formed. The particles that scientists measure can form in various ways: from the original soup of quarks and gluons or from later reactions.

These later reactions began 0.000001 seconds after the Big Bang, when the composite particles made of quarks began to interact with each other.

A new calculation determined that as much as 70% of some measured particles are from these later reactions, not from reactions similar to those of the early universe. The research is published in the journal Physics Letters B.

This finding improves scientific understanding of the origins of matter. It helps identify how much of the matter around us formed in the first few fractions of a second after the Big Bang, versus how much matter formed from later reactions as the universe expanded.

This result implies large amounts of the matter around us formed later than expected. To understand the results of collider experiments, scientists must discount the particles formed in the later reactions.

Only those formed in the subatomic soup reveal the early conditions of the universe. This new calculation shows that the number of measured particles formed in reactions is much higher than expected.

Joseph Dominicus Lap et al, Hadronic J/ψ regeneration in Pb+Pb collisions, Physics Letters B (2023). DOI: 10.1016/j.physletb.2023.138246

Comment by Dr. Krishna Kumari Challa on July 30, 2024 at 8:10am

Losing a loved one may speed up aging, study finds

Losing someone close, like a family member, can make you age faster, says a new study.

The study found that people who lost a parent, partner, sibling, or child, showed signs of older biological age compared to those who hadn't experienced such losses. The research was published in JAMA Network Open.

Biological aging is the gradual decline in how well your cells, tissues, and organs function, leading to a higher risk of chronic diseases. Scientists measure this type of aging using DNA markers known as epigenetic clocks.

The study suggests that the impact of loss on aging can be seen long before middle age and may contribute to health differences among racial and ethnic groups.

The study also confirmed that people who experienced two or more losses had older biological ages according to several epigenetic clocks. Experiencing two or more losses in adulthood was more strongly linked to biological aging than one loss and significantly more so than no losses.

Losing a parent or sibling early in life can be very traumatic, often leading to mental health issues, cognitive problems, higher risks of heart disease, and a greater chance of dying earlier. Losing a close family member at any age poses health risks, and repeated losses can increase the risks of heart disease, mortality, and dementia; and impacts may persist or become apparent long after the event.

Familial Loss of a Loved One and Biological Aging, JAMA Network Open (2024).

 https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2821615

Comment by Dr. Krishna Kumari Challa on July 30, 2024 at 8:02am

Virus that causes COVID-19 is widespread in wildlife

SARS-CoV-2, the virus responsible for COVID-19, is widespread among wildlife species, according to  new research published July 29, 2024 in Nature Communications. The virus was detected in six common backyard species, and antibodies indicating prior exposure to the virus were found in five species, with rates of exposure ranging from 40 to 60% depending on the species.

Genetic tracking in wild animals confirmed both the presence of SARS-CoV-2 and the existence of unique viral mutations with lineages closely matching variants circulating in humans at the time, further supporting human-to-animal transmission, the study found.

The highest exposure to SARS CoV-2 was found in animals near hiking trails and high-traffic public areas, suggesting the virus passed from humans to wildlife, according to scientists.

The findings highlight the identification of novel mutations in SARS-CoV-2 in wildlife and the need for broad surveillance, researchers say. These mutations could be more harmful and transmissible, creating challenges for vaccine development.

The scientists stressed, however, that they found no evidence of the virus being transmitted from animals to humans, and people should not fear typical interactions with wildlife.

Widespread exposure to SARS-CoV-2 in wildlife communities, Nature Communications (2024). DOI: 10.1038/s41467-024-49891-w

Comment by Dr. Krishna Kumari Challa on July 30, 2024 at 7:54am

A passive, renewable, more efficient way to extract water from the atmosphere

Freshwater scarcity affects  billions of people in the world, primarily in arid and remote regions, as well as islands and coastal areas without freshwater sources. Climate change and population growth are only making the problem worse, and existing methods require an energy input, usually electrical.

Renewable energy can fix this and is required for these regions for drinking water and irrigation, using water extracted from the atmosphere.

It is estimated the atmosphere holds about 13 trillion tons of water, six times the freshwater in the globe's rivers; global warming allows the air to hold more water vapor, by a theoretical 7% per degree Celsius of warming.

Now engineers and scientists  have created a system that uses  solar energy to extract as much as 3 liters (0.8 gallons) of water per square meter per day from air, in a purely passive way, requiring no maintenance or human operators. The study is published in the journal Nature Communications.

Existing solar-driven atmospheric water extraction (SAWE) systems typically rely on absorbing water vapor from the air. When the absorbing material reaches saturation, the system is sealed and exposed to sunlight, which begins the release of the captured water. They are an improvement over passive atmospheric water technologies such as fog and dew collection, and more available in other geographies and sites with climate constraints.

To design a passive, efficient, easily scalable and minimal-labor system, the group used a structure of multiple vertical microchannels, called mass transport bridges. The tubes, sitting in a container, are filled with a liquid salt solution that acts as a liquid absorber; they used lithium chloride.

Depending on the temperature distribution, the ambient temperature region, exposed to the environment, continuously captures atmospheric water and stores it in a container. When the system receives sunlight, the absorber converts the light into heat and generates concentrated water vapor in the high-temperature region.

The water vapor condenses on the chamber wall, producing freshwater. More captured water from the absorber's container moves uninterrupted to the high-temperature region.

At the same time, the concentrated liquid in the high-temperature region is transported back to the ambient temperature region via diffusion—the movement of molecules from a region of high concentration to low concentration—and by convection—the movement of the hotter, lower density solution through the colder, denser regions—enabling continuous capture of water vapor as long as sunlight is available.

Kaijie Yang et al, A solar-driven atmospheric water extractor for off-grid freshwater generation and irrigation, Nature Communications (2024). DOI: 10.1038/s41467-024-50715-0

Comment by Dr. Krishna Kumari Challa on July 29, 2024 at 11:02am

Blood thinner stops cobra venom
A common blood thinner can fight the toxins in cobra venom, potentially preventing limb amputations caused by snakebites. Using the genetic editing tool CRISPR, researchers found that eliminating certain sugars on the outside of human cells allowed the cells to resist cobra toxins. In experiments with mice, a class of drugs known as heparinoids soaked up the toxin and shrank venom-induced wounds by 94%. The drugs worked against several cobra species’ venoms, but not against viper venoms.

https://www.science.org/doi/10.1126/scitranslmed.adk4802?utm_source...

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