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Comment by Dr. Krishna Kumari Challa on June 20, 2024 at 9:22am

Travelers urged to keep it local in the name of sustainable tourism

From rolling vineyards to stunning beaches, there's no shortage of beauty to discover in our own backyards.

A tourism expert from the University of South Australia is urging travelers to support local destinations and experiences close to home, instead of long-haul international trips, to lessen the impacts of tourism on the environment.

Adjunct Senior Lecturer in Tourism Management Dr. Freya Higgins-Desbiolles says we should be considering more localized travel and doing everything we can to reduce unnecessary emissions.

She says space travel, private jet travel and mass travel to far off and remote and extreme environments are "unethical" and contribute to a culture of privileged over-consumption.

"In these conditions, it is hard to justify tourism . We have to question our use of cruising or flights in our tourism consumption," she says.

We need to create a cultural shift that sees tourism consumption as a luxury to be savored and not something we can have every year or multiple times a year, like many have come to expect in the Global North. Shifting to an appreciation of local leisure and domestic travels and lower expectations of long-haul international travel is a must.

The Global North, i.e., the northern hemisphere, is responsible for 92% of global emissions.

Dr. Higgins-Desbiolles outlines how tourism is contributing to the depletion of natural resources, pollution, over-consumption and environmental destruction.

Part 1

Comment by Dr. Krishna Kumari Challa on June 20, 2024 at 9:14am

Air pollution linked to nearly 2,000 child deaths a day: Report

Nearly 2,000 children die every day from health problems linked to air pollution, which is now the second biggest risk factor for early death worldwide, a report said recently.

Exposure to air pollution contributed to the deaths of 8.1 million people—around 12 percent of all fatalities—in 2021, according to the report from the US-based Health Effects Institute.

This means air pollution has overtaken tobacco use and poor diet to become the second leading risk factor for early death, behind only high blood pressure, it said.

Little kids are particularly vulnerable to air pollution, and the institute partnered with the UN Children's Fund UNICEF for its annual State of Global Air report.

Air pollution contributed to the deaths of more than 700,000 children under the age of five, the report found.

More than 500,000 of those deaths were attributed to cooking indoors using dirty fuels such as coal, wood or dung, mostly in Africa and Asia.

Nearly every person in the world breathes unhealthy levels of air pollution every day, the report found. Over 90 percent of the deaths were linked to tiny airborne pollutants called PM2.5, which measure 2.5 micrometres or less, it said. Inhaling PM2.5 has been found to increase the risk of lung cancer, heart disease, stroke, diabetes and a range of other health problems.

The report aimed to link the rates of such diseases with air pollution levels.

But despite the "pretty stark" figures, the report could still be underestimating air pollution's impact, according to experts.

It did not take into account, for instance, how air pollution could affect brain health, neurodegenerative diseases or what impact using solid fuels for heating could have.

The report also found that ozone pollution—which is expected to get worse as the world warms due to human-driven climate change—was linked to nearly 500,000 deaths in 2021.

Source: AFP and other news agencies

https://ceh.unicef.org/spotlight-risk/air-pollution

Comment by Dr. Krishna Kumari Challa on June 20, 2024 at 8:33am

New technology provides electrifying insights into how catalysts work at the atomic level

A team led by Lawrence Berkeley National Laboratory (Berkeley Lab) has invented a technique to study electrochemical processes at the atomic level with unprecedented resolution and used it to gain new insights into a popular catalyst material.

Electrochemical reactions—chemical transformations that are caused by or accompanied by the flow of electric currents—are the basis of batteries, fuel cells, electrolysis, and solar-powered fuel generation, among other technologies. They also drive biological processes such as photosynthesis and occur under the Earth's surface in the formation and breakdown of metal ores.

The scientists have developed a cell—a small enclosed chamber that can hold all the components of an electrochemical reaction—that can be paired with transmission electron microscopy (TEM) to generate precise views of a reaction at an atomic scale. Better yet, their device, which they call a polymer liquid cell (PLC), can be frozen to stop the reaction at specific timepoints, so scientists can observe composition changes at each stage of a reaction with other characterization tools.

In a paper appearing in Nature, the team describes their cell and a proof of principle investigation using it to study a copper catalyst that reduces carbon dioxide to generate fuels.

Haimei Zheng, Atomic dynamics of electrified solid–liquid interfaces in liquid-cell TEM, Nature (2024). DOI: 10.1038/s41586-024-07479-w. www.nature.com/articles/s41586-024-07479-w

Comment by Dr. Krishna Kumari Challa on June 20, 2024 at 8:26am

Researchers create new class of materials called 'glassy gels'

Researchers have created a new class of materials called "glassy gels" that are very hard and difficult to break despite containing more than 50% liquid. Coupled with the fact that glassy gels are simple to produce, the material holds promise for a variety of applications.

A paper describing this work, titled "Glassy Gels Toughened by Solvent," appears in the journal Nature.

Gels and glassy polymers are classes of materials that have historically been viewed as distinct from one another. Glassy polymers are hard, stiff and often brittle. They're used to make things like water bottles or airplane windows. Gels—such as contact lenses—contain liquid and are soft and stretchy.

Now researchers have created a class of materials that they've termed glassy gels, which are as hard as glassy polymers, but—if you apply enough force—can stretch up to five times their original length, rather than breaking.

What's more, once the material has been stretched, you can get it to return to its original shape by applying heat. In addition, the surface of the glassy gels is highly adhesive, which is unusual for hard materials.

A key thing that distinguishes glassy gels is that they are more than 50% liquid, which makes them more efficient conductors of electricity than common plastics that have comparable physical characteristics.

Considering the number of unique properties they possess, researchers are optimistic that these materials will be very useful.

Michael Dickey, Glassy gels toughened by solvent, Nature (2024). DOI: 10.1038/s41586-024-07564-0. www.nature.com/articles/s41586-024-07564-0

Comment by Dr. Krishna Kumari Challa on June 19, 2024 at 11:25am

Starlings found to expend 25% less energy in follower position compared to flying solo

A multidisciplinary, multi-institutional team of researchers  has found that starlings that fly in a follower position expend 25% less energy than when they fly solo. In their study, published in the Proceedings of the National Academy of Sciences, the group designed complex experiments to learn more about the amount of energy savings for birds following another bird in flight rather than going it alone.

Prior research and logic suggest that if a bird were to fly behind another bird, it would use less energy because there would be less wind resistance. But testing the idea has proven difficult. In this new effort, the research team designed and carried out what they describe as "difficult" experiments to test energy expenditure by birds in flight.

Sonja I. Friman et al, It pays to follow the leader: Metabolic cost of flight is lower for trailing birds in small groups, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2319971121

Comment by Dr. Krishna Kumari Challa on June 19, 2024 at 11:07am

Discovery of 'new rules of the immune system' could improve treatment of inflammatory diseases, say scientists

Scientists  have discovered that a type of white blood cell—called a regulatory T cell—exists as a single large population of cells that constantly move throughout the body looking for, and repairing, damaged tissue.

This overturns the traditional thinking that regulatory T cells exist as multiple specialist populations that are restricted to specific parts of the body. The finding has implications for the treatment of many different diseases—because almost all diseases and injuries trigger the body's immune system.

Current anti-inflammatory drugs treat the whole body, rather than just the part needing treatment. The researchers say their findings mean it could be possible to shut down the body's immune response and repair damage in any specific part of the body, without affecting the rest of it. This means that higher, more targeted doses of drugs could be used to treat disease—potentially with rapid results.

Researchers have uncovered new rules of the immune system. This 'unified healer army' can do everything—repair injured muscle, make your fat cells respond better to insulin, regrow hair follicles. To think that we could use it in such an enormous range of diseases is fantastic: it's got the potential to be used for almost everything.

To reach this discovery, the researchers analyzed the regulatory T cells present in 48 different tissues in the bodies of mice. This revealed that the cells are not specialized or static, but move through the body to where they're needed. The results are published in the journal Immunity.

Most white blood cells attack infections in the body by triggering an immune response. In contrast, regulatory T cells act like a 'unified healer army' whose purpose is to shut down this immune response once it has done its job—and repair the tissue damage caused by it.

The tissue-resident regulatory T cell pool is shaped by transient multi-tissue migration and a conserved residency program, Immunity (2024). DOI: 10.1016/j.immuni.2024.05.023. www.cell.com/immunity/fulltext … 1074-7613(24)00277-2

Comment by Dr. Krishna Kumari Challa on June 19, 2024 at 10:15am

Study reveals genetic basis of sepsis response variability

Sepsis causes an estimated 11 million deaths worldwide per year, with one death every three seconds. 

Sepsis response varies between patients and depends on the different underlying immune response pathways.

Sepsis patients could be treated based on their immune system's response to infection, not their symptoms.

New research uncovers how different people respond to sepsis based on their genetic makeup, which could help identify who would benefit from certain treatments and lead to the development of targeted therapies.

The study, published in Cell Genomics, details the genetic basis of variability in sepsis response, and the different regulators and cell types involved in the different immune responses in each subgroup of patients.

Having a more detailed understanding of sepsis at a molecular level could identify those who would benefit from different therapies, helping to design rapid tests, organize clinical trials, and develop targeted treatments based on the individual immune response.

The ultimate aim is for patients to receive the most effective treatment for their sepsis more quickly, based on their immune response rather than their symptoms. In the future, this approach to personalized medicine could also be applied to other less severe infections, not just sepsis.

Sepsis arises when the body has an extreme response to an infection and injures its own tissues and organs. Sepsis can cause different downstream immune responses in different people. Depending on this immune response, the treatment varies. However, it is difficult to identify which response is happening based on symptoms alone. Sepsis can progress quickly, and if the wrong treatment is given, valuable time could be lost.

Understanding the regulatory networks underlying the different patient responses provides additional information for developing treatments that work with the immune system and are a step towards a personalized medicine approach to treating sepsis.

K. Burnham, eQTLs identify regulatory networks and drivers of variation in the individual response to sepsis, Cell Genomics (2024). DOI: 10.1016/j.xgen.2024.100587. www.cell.com/cell-genomics/ful … 2666-979X(24)00171-X

Comment by Dr. Krishna Kumari Challa on June 19, 2024 at 9:58am

More than a century ago, researchers observed that rats that consumed less food lived longer. We now know that being able to manipulate lifespan is not about specifically eating less, but actually is related to signals inside cells that turn on and off specific pathways in response to available nutrients. Many of those pathways are related to aging, such as controlling protein turnover and metabolism.

Some of those signals are the ketone bodies, which consist of acetoacetate (AcAc), β-hydroxybutyrate (BHB) and to a much lesser extent, acetone. These molecules are routinely produced in the liver. They ramp up when glucose is in short supply, whether due to caloric restriction, intense exercise or low carbohydrate intake, such as with a ketogenic diet.

Diego Acuña-Catalán et al, Ketogenic diet administration later in life improves memory by modifying the synaptic cortical proteome via the PKA signaling pathway in aging mice, Cell Reports Medicine (2024). DOI: 10.1016/j.xcrm.2024.101593

Comment by Dr. Krishna Kumari Challa on June 19, 2024 at 9:54am

Large wildfires create weather that favours more fire

A new  study shows soot from large wildfires in California traps sunlight, making days warmer and drier than they ought to be.

Many studies look at the effect of climate change on wildfires. However, this study sought to understand the reverse—whether large fires are also changing the climate.

Published in the journal Atmospheric Chemistry and Physics, the study found that large fires did have an effect. They made it hotter and drier than usual on the days the fires burned. The extra heat and aridity may then make conditions favorable for more fire.

It appears these fires are creating their own fire weather.

There are likely two reasons for this. One—soot traps heat, and two —the extra heat reduces humidity in the atmosphere, making it more difficult for clouds to form.

Fires emit smoke with black carbon, or soot. Since it is very dark, the soot absorbs sunlight more readily than bright or reflective things.

There are two types of aerosols: reflective and absorptive. Sulfate aerosols, which are byproducts of fossil fuel burning, are reflective and can cool the environment. These particles reflect the sun's energy back into space, keeping it out of the atmosphere.

Recent research points to an unfortunate byproduct of improving air quality by reducing sulfate aerosols. Since these particles have a cooling effect, removing them makes climate change more severe and leads to an increase in wildfires, especially in northern hemisphere forests.

Sulfate aerosols can also help make clouds brighter, more reflective, and more effective at cooling the planet.

The researchers note that the only way to prevent additional wildfires when cleaning up reflective sulfate air pollution is to simultaneously reduce emissions of greenhouse gases like carbon dioxide and methane.

Absorptive aerosols have the opposite effect. They trap light and heat in the atmosphere, which can raise temperatures. Black carbon, the most common aerosol emission from wildfires, is an absorbing aerosol. They not only directly make temperatures hotter, but indirectly as well by discouraging cloud formation and precipitation.

Fewer clouds mean less precipitation, which is problematic for drought-prone states.While some studies have shown an association between fires and brighter, more numerous clouds, this one did not.

James L. Gomez et al, California wildfire smoke contributes to a positive atmospheric temperature anomaly over the western United States, Atmospheric Chemistry and Physics (2024). DOI: 10.5194/acp-24-6937-2024

Comment by Dr. Krishna Kumari Challa on June 19, 2024 at 9:41am

Massive black holes—with masses over one hundred thousand times that of our sun—exist at the center of most galaxies, including the Milky Way.

These giant monsters usually are sleeping and not directly visible. In the case of SDSS1335+0728, scientists were able to observe the awakening of the massive black hole, which suddenly started to feast on gas available in its surroundings, becoming very bright.
This process has never been observed before.
Follow-up observations are still needed to rule out alternative explanations. Another possibility is that we are seeing an unusually slow tidal disruption event, or even a new phenomenon. If it is in fact a tidal disruption event, this would be the longest and faintest such event ever observed.

SDSS1335+0728: The awakening of a ∼ 10⁶M⊙ black hole, Astronomy & Astrophysics (2024). (PDF)

Part 2

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