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Comment by Dr. Krishna Kumari Challa on October 11, 2024 at 11:09am

The new fashion: Clothes that help combat rising temperatures

A team of international researchers has developed a natural fabric that urban residents could wear to counter rising temperatures in cities worldwide, caused by buildings, asphalt, and concrete.

As heat waves become more prominent, cooling textiles that can be incorporated into clothes, hats, shoes and even building surfaces provide a glimpse into a future where greenhouse gas-emitting air conditioners may no longer be needed in our cities.

Engineers  say the wearable fabric is designed to reflect sunlight and allow heat to escape, while blocking the sun's rays and lowering the temperature. They have described the textiles in Science Bulletin.

The fabric promises to bring relief to millions of city dwellers experiencing warmer and more uncomfortable temperatures caused by global climate change and fewer green spaces.

 The fabric leverages the principle of radiative cooling, a natural process where materials emit heat into the atmosphere, and ultimately into space.

Unlike conventional fabrics that retain heat, these textiles are made of three layers that are engineered to optimize cooling. 

The upper layer, made of polymethyl pentene fibers, allows heat to radiate effectively. The middle layer, composed of silver nanowires, enhances the fabric's reflectivity, preventing additional heat from reaching the body. The bottom layer, made of wool, directs heat away from the skin, ensuring that wearers remain cool, even in the hottest urban environments.

In the experiments conducted, when placed vertically, the fabric was found to be 2.3°C cooler than traditional textiles, and up to 6.2°C cooler than the surrounding environment when used as a horizontal surface covering.

The fabric's ability to passively reduce temperatures offers a sustainable alternative to conventional air conditioning, providing energy savings and reducing the strain on power grids during heat waves.

It is hoped the technology could be adapted for even broader applications, including construction materials, outdoor furniture and urban planning.

While the fabric holds significant promise, researchers say the current production process is costly, and the long-term durability of the textiles needs further investigation and government support before it can be commercialized.

Xianhu Liu et al, Radiation cooling textiles countering urban heat islands, Science Bulletin (2024). DOI: 10.1016/j.scib.2024.09.008

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Comment by Dr. Krishna Kumari Challa on October 11, 2024 at 10:56am

Comment by Dr. Krishna Kumari Challa on October 11, 2024 at 10:33am

Personal care products affect indoor air quality

The personal care products we use on a daily basis significantly affect indoor air quality, according to new research.

When used indoors, these products release a cocktail of more than 200 volatile organic compounds (VOCs) into the air, and when those VOCs come into contact with ozone, the chemical reactions that follow can produce new compounds and particles that may penetrate deep into our lungs. Scientists are now wondering how inhaling these particles on a daily basis affects our respiratory health.

These products are roll-on deodorant, spray deodorant, hand lotion, perfume and dry shampoo hair spray—all produced by leading brands and available in major stores across the world. 

During their experiments, in one test, the researchers applied the products under typical conditions, while the air quality was carefully monitored. In another test, they did the same thing but also injected ozone, a reactive outdoor gas that occurs in some latitudes during the summer months.

Ozone can infiltrate homes through open windows, but can also come from indoors, for example, when using laser printers and 3D printers. Around five sophisticated measuring instruments were deployed to quantify and identify the gases and particles present in the chamber.

It took the scientists two years to process all the collected data. In the first case without ozone, over 200 VOCs were emitted from the personal care products, which gradually dissipated with ventilation. The most abundant molecules they found were ethanol and monoterpenes, typically used in these products. However, when ozone was introduced into the chamber, not only new VOCs but also new particles were generated, particularly from perfume and sprays, exceeding concentrations found in heavily polluted urban areas.

Some molecules 'nucleate'—in other words, they form new particles that can coagulate into larger ultrafine particles that can effectively deposit into our lungs.

We still don't fully understand the health effects of these pollutants, but they may be more harmful than we think, especially because they are applied close to our breathing zone. This is an area where new toxicological studies are needed, say the researchers.

To limit the effect of personal care products on indoor air air quality, we could consider several alternatives for how buildings are engineered: introducing more ventilation—especially during the products' use—incorporating air-cleaning devices (e.g., activated carbon-based filters combined with media filters), and limiting the concentration of indoor ozone.

The researchers stress that we're going to have to reduce our reliance on these products, or if possible, replace them with more natural alternatives that contain fragrant compounds with low chemical reactivity. Another helpful measure would be to raise awareness of these issues among medical professionals and staff working with vulnerable groups, such as children and the elderly.

Tianren Wu et al, Indoor Emission, Oxidation, and New Particle Formation of Personal Care Product Related Volatile Organic Compounds, Environmental Science & Technology Letters (2024). DOI: 10.1021/acs.estlett.4c00353

Comment by Dr. Krishna Kumari Challa on October 11, 2024 at 10:07am

Microscopic marine organisms can create parachute-like mucus structures that stall CO₂ absorption from atmosphere

New research unveils a hidden factor that could change our understanding of how oceans mitigate climate change. The study, published Oct. 11 in Science, reveals never-before seen mucus "parachutes" produced by microscopic marine organisms that significantly slow their sinking, putting the brakes on a process crucial for removing carbon dioxide from the atmosphere.

The surprising discovery implies that previous estimates of the ocean's carbon sequestration potential may have been overestimated, but also paves the way toward improving climate models and informing policymakers in their efforts to slow climate change.

Rahul Chajwa et al, Hidden comet tails of marine snow impede ocean-based carbon sequestration, Science (2024). DOI: 10.1126/science.adl5767. www.science.org/doi/10.1126/science.adl5767

Comment by Dr. Krishna Kumari Challa on October 11, 2024 at 10:03am

New nanotherapy targets artery inflammation in cardiovascular disease

Inflammation of the arteries is a primary precursor and driver of cardiovascular disease—the No. 1 killer of people in some countries. This inflammation is associated with the buildup of dangerous plaque inside the arteries. Advanced treatments are needed to target this inflammation in patients. 

Researchers have tested a new nanoparticle nanotherapy infusion that precisely targets inflammation and activates the immune system to help clear out arterial plaque.

The research is published in the journal Nature Communications.

There are two different things that people seem to be scared of when it comes to plaques.

The first example is when your artery becomes blocked (for example, a 95% to 99% blockage). Often, there are symptoms like pain or pressure in the chest or nausea and dizziness beforehand and doctors will put a stent in the artery to increase blood flow.

The second is when the plaque is highly inflammatory. This can make the plaque vulnerable to rupture, which can lead to artery blockages elsewhere in the body. That's the scarier one that leads to most heart attacks. Because such plaques don't necessarily block much of the artery, and because the effects of the rupture can very suddenly completely block blood flow, such a heart attack can seem to appear as if from nowhere.

Researchers now created nanoparticles—materials that are thinner than a human hair—that they used to develop a nanotherapy infusion. The nanotherapy selectively targets a specific immune cell type that moves into and is a part of the plaque. These treated cells "eat" away parts of the plaque core, removing it from the artery wall and decreasing levels of blood vessel inflammation.

In previous studies they tested the infusion on mice and now, pig models, to prove the infusion's effectiveness, and critically, its lack of side effects due to its precision immune targeting.

Using PET [positron-emission tomography] scans, they were able to measure the effects of the therapy on pig arteries. 

They  showed in animal models such as pigs that they can decrease the levels of inflammation in the plaque based not only on this clinically used PET imaging technique but also by molecular assays. Just as importantly, they saw none of the side effects that would have been anticipated had the therapy not been precisely targeted.

 Sharika Bamezai et al, Pro-efferocytic nanotherapies reduce vascular inflammation without inducing anemia in a large animal model of atherosclerosis, Nature Communications (2024). DOI: 10.1038/s41467-024-52005-1

Comment by Dr. Krishna Kumari Challa on October 11, 2024 at 9:46am

When the organic solvent wash was mixed in quickly, the silk solution rapidly created fibers with high tensile strength and stickiness. Dopamine and its polymers employ the same chemistry used by barnacles to form fibers that stick tenaciously to surfaces.

The next step was to spin the fibers in air. The researchers added dopamine to the silk fibroin solution, which appears to accelerate the transition from liquid to solid by pulling water away from the silk. When shot through a coaxial needle, a thin stream of the silk solution is surrounded by a layer of acetone which triggers the solidification.

The acetone evaporates in mid-air, leaving a fiber attached to any object it contacts. The researchers enhanced the silk fibroin-dopamine solution with chitosan, a derivative of insect exoskeletons that gave the fibers up to 200 times greater tensile strength, and borate buffer, which increased their adhesiveness about 18-fold.

The diameter of the fibers could be varied between that of a human hair to about half a millimeter, depending on the bore of the needle.
The device can shoot fibers that can pick up objects over 80 times their own weight under various conditions. The researchers demonstrated this by picking up a cocoon, a steel bolt, a laboratory tube floating on water, a scalpel partially buried in sand, and a wood block from a distance of about 12 centimeters.
Who says fiction cannot become fact?
With science everything is possible.

 Marco Lo Presti et al, Dynamic Adhesive Fibers for Remote Capturing of Objects, Advanced Functional Materials (2024). DOI: 10.1002/adfm.202414219

Part 2

Comment by Dr. Krishna Kumari Challa on October 11, 2024 at 9:44am

Creating spider-man's world: researchers recreate web-slinging technology

Every person who has read a comic book or watched a Spider-Man movie has tried to imagine what it would be like to shoot a web from their wrist, fly over streets, and pin down villains. Researchers  took those imaginary scenes seriously and created the first web-slinging technology in which a fluid material can shoot from a needle, immediately solidify as a string, and adhere to and lift objects.

The study is published in the journal Advanced Functional Materials.

These sticky fibers, created at the Tufts University Silklab, come from silk moth cocoons, which are boiled in solution and broken down into their building block proteins called fibroin. The silk fibroin solution can be extruded through narrow bore needles to form a stream that, with the right additives, solidifies into a fiber when exposed to air.

Of course, nature is the original inspiration for deploying fibers of silk into tethers, webs, and cocoons. Spiders, ants, wasps, bees, butterflies, moths, beetles, and even flies can produce silk at some point in their lifecycle.

Nature also inspired the Silklab to pioneer the use of silk fibroin to make powerful glues that can work underwater, printable sensors that can be applied to virtually any surface, edible coatings that can extend the shelf life of produce, a light collecting material that could significantly enhance the efficiency of solar cells, and more sustainable microchip manufacturing methods . However, while they made significant progress with silk-based materials, the researchers had yet to replicate the mastery of spiders, which can control the stiffness, elasticity, and adhesive properties of the threads they spin. 

Silk fibroin solutions can slowly form a semi-solid hydrogel over a period of hours when exposed to organic solvents like ethanol or acetone, but the presence of dopamine, which is used in making the adhesives, allowed the solidification process to occur almost immediately.

Part 1

Comment by Dr. Krishna Kumari Challa on October 10, 2024 at 11:43am

First, they had to rule out that any microbes they found were indigenous to the habitat, and not the result of contamination from the extraction process. They used a technique they developed several years ago that involves sterilizing the outside of the sample before cutting it into slices to examine its contents.

Then, they used a cyanine dye to stain the slices. This dye binds to DNA, so if there is any DNA in the sample, it should light up like a Christmas tree when subjected to infrared spectroscopy. And this is exactly what happened.

The sample was also riddled with clay, which packed veins near the pockets in the rock near the microbial colonies.

The result of this clay packing was multifold: it provided a resource for the microbes to live on, with organic and inorganic materials that they could metabolize; and it effectively sealed the rock, both preventing the microbes from escaping, and preventing anything else from entering – including the drilling fluid.

The microbial community in the rock will need to be analyzed in greater detail, including DNA analysis, to determine how it has changed or not changed in the 2 billion years it has been sequestered away from the rest of life on Earth.

https://link.springer.com/article/10.1007/s00248-024-02434-8

Part 2

Comment by Dr. Krishna Kumari Challa on October 10, 2024 at 11:41am

Microbes Found Alive Sealed in Rock For 2 Billion Years

Deep underground, in the darkness far below the bustling activity on the surface, a community of microbes has been living their best lives in isolation.

What makes these organisms incredibly special is that they have been cut off for billions of years – far longer than any other community of subterranean microbes we've ever seen. This find of living microbes in 2 billion-year-old rock absolutely smashes the previous record of 100 million years.

And it's a significant one: microbes in isolated underground pockets like these tend to evolve more slowly, since they're detached from many of the pressures that drive evolution in more populated habitats.

This means that the microbe community can tell us things we might not have known about microbe evolution here on Earth. But it also suggests that there might be underground microbe communities still alive on Mars, surviving long after the water on the surface dried out.

By studying the DNA and genomes of microbes like these, we may be able to understand the evolution of very early life on Earth.

The sample of rock was drilled from 15 meters (50 feet) underground from a formation known as the Bushveld Igneous Complex in northeastern South Africa. This formation is huge, a 66,000 square kilometer (25,500 square mile) intrusion into Earth's crust that formed some 2 billion years ago from molten magma cooling below the surface.

Part 1

Comment by Dr. Krishna Kumari Challa on October 10, 2024 at 10:42am

Scientists propose a new bias: The tendency to assume one has adequate information to make a decision

They call it the illusion of information adequacy.

New experimental data support the idea that people tend to assume the information they have is adequate to comprehend a given situation, without considering that they might be lacking key information.

When navigating alternative perspectives, people may demonstrate psychological biases that influence their ability to understand others' viewpoints. For instance, in the bias of naive realism, people presume their own subjective perspective is objective truth.

The illusion of information adequacy: the failure to consider the possibility that one might be missing key information.

Moreover, a subgroup of participants who later received the information they initially lacked tended to stick with their original decisions. Hmmm!

Scientists just shut their mouths and wonder how inadequate human perceptions are!

A major source of misunderstanding and conflict in our daily lives arises from this paradox: We know that, in theory, there are plenty of things that we don't know we don't know. Yet, in practice, we almost always behave as though we have adequate information to voice our opinions, make good decisions, and pass judgment on others. A little more intellectual humility about what we do and don't know would serve us well.

If you don't have this, scientists don't give a damn to your opinion or decision. 

Now you know why we don't care  about your opinions, talk, decisions and judgements with regard to science. 

 

The illusion of information adequacy, PLoS ONE (2024). DOI: 10.1371/journal.pone.0310216

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