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Comment by Dr. Krishna Kumari Challa on May 19, 2021 at 10:24am

COVID-19 Insights: Will Steam Kill the SARS-COV-2 inside The Cells?

Comment by Dr. Krishna Kumari Challa on May 19, 2021 at 9:28am

European fire ant chemicals may send spiders scurrying away

But don’t go adding the invasive, biting insects to your home as an arachnid repellent

To make a spider flee, bring on the fire ants. Or rather, just their chemical signals.

Some spiders common in North American homes avoid building their webs in chambers that recently housed European..., researchers report May 19 in Royal Society Open Science. The ants probably left behind chemical traces, the researchers say. That could signal danger to the arachnids because ants sometimes feast on spiders. The reaction hints that the insects might be a source of natural spider-repelling chemicals.

https://www.sciencenews.org/article/european-fire-ant-chemicals-spi...

Comment by Dr. Krishna Kumari Challa on May 19, 2021 at 8:29am

How lightning may help clean the air

Lightning may play an important role in clearing the air of pollutants.

A storm-chasing airplane has shown that lightning can forge large amounts of oxidants. These chemicals cleanse the atmosphere by reacting with pollutants such as methane. Those reactions form molecules that dissolve in water or stick to surfaces. The molecules can then rain out of the air or stick to objects on the ground.
Researchers knew lightning could produce oxidants indirectly. The bolts generate nitric oxide. That chemical can react with other molecules in the air to make some oxidants. But no one had seen lightning directly create lots of oxidants.

A NASA jet got the first glimpse of this in 2012. The jet flew through storm clouds over Colorado, Oklahoma and Texas in both May and June. Instruments on board measured two oxidants in the clouds. One was hydroxyl radical, or OH. The other was a related oxidant. It’s called the hydroperoxyl (Hy-droh-pur-OX-ul) radical, or HO2. The airplane measured the combined concentration of both in the air.
Lightning and other electrified parts of the clouds sparked the creation of OH and HO2. Levels of these molecules rose to thousands of parts per trillion. That may not sound like much. But the most OH seen in the atmosphere before was only a few parts per trillion. The most HO2 ever seen in the air was about 150 parts per trillion. Researchers reported the observations online April 29 in Science.

https://science.sciencemag.org/content/372/6543/711

Comment by Dr. Krishna Kumari Challa on May 19, 2021 at 7:23am

World first concept for rechargeable cement-based batteries

The concept involves a cement-based mixture with small amounts of short carbon fibres added to increase the conductivity and flexural toughness. Embedded within the mixture is a metal-coated carbon fibre mesh—iron for the anode, and nickel for the cathode. After much experimentation, this is the prototype the researchers now present.

Emma Qingnan Zhang et al, Rechargeable Concrete Battery, Buildings (2021). DOI: 10.3390/buildings11030103

https://techxplore.com/news/2021-05-world-concept-rechargeable-ceme...

Comment by Dr. Krishna Kumari Challa on May 19, 2021 at 7:12am

Scientists debut most efficient 'optical rectennas,' devices that harvest power from heat

Scientists have tapped into a unique property of electrons to design devices that can capture excess heat from their environment—and turn it into usable electricity.

The researchers have described their new "optical rectennas" in a paper published recently in the journal Nature Communications. These devices, which are too small to see with the naked eye, are roughly 100 times more efficient than similar tools used for energy harvesting. And they achieve that feat through a mysterious process called "resonant tunneling"—in which electrons pass through solid matter without spending any energy.

Rectennas (short for "rectifying antennas") work a bit like car radio antennas. But instead of picking up radio waves and turning them into tunes, optical rectennas absorb light and heat and convert it into power.

They're also potential game changers in the world of renewable energy. Working rectennas could, theoretically, harvest the heat coming from factory smokestacks or bakery ovens that would otherwise go to waste. Some scientists have even proposed mounting these devices on airships that would fly high above the planet's surface to capture the energy radiating from Earth to outer space.

But, so far, rectennas haven't been able to reach the efficiencies needed to meet those goals. Until now, perhaps. In the new study, researchers have designed the first-ever rectennas that are capable of generating power.

Scientists demonstrate for the first time electrons undergoing resonant tunneling in an energy-harvesting optical rectenna. Until now, it was only a theoretical possibility.

 Nature Communications (2021). DOI: 10.1038/s41467-021-23182-0

https://techxplore.com/news/2021-05-scientists-debut-efficient-opti...

Comment by Dr. Krishna Kumari Challa on May 19, 2021 at 6:55am

Comment by Dr. Krishna Kumari Challa on May 18, 2021 at 11:40am

Scientists construct first-ever synthetic DNA-like polymer

Double helical covalent polymers—which are spiraling collections of nature's building blocks—are fundamental to life itself, and yet, despite decades of research, scientists have never been able to synthesize them in their entirety like their non-helical brethren—until now.

have cracked the code, creating synthetic versions of these large DNA-like molecules for the first time. Using dynamic covalent chemistry, which is a chemistry tool pioneered by these researchers that focuses on reversible bonding interactions with self-correction capabilities, they were able to not only construct a helical covalent polymer that rivals the sophistication of those found in nature but confirm its existence with absolute certainty using single crystal X-ray diffraction (a powerful, non-destructive way to characterize single crystals using light).

Previously, scientists have only been able to solve individual parts of the puzzle. This new discovery out last week in Nature Chemistry, though, completes it, potentially opening this critical and understudied field to new research that could have implications on everything from artificial enzyme creation, which has already found success in various medical applications, to the creation of biomimetic materials (materials that mimic processes found in nature).

Yiming Hu et al. Single crystals of mechanically entwined helical covalent polymers, Nature Chemistry (2021). DOI: 10.1038/s41557-021-00686-2

https://phys.org/news/2021-05-scientists-first-ever-synthetic-dna-l...

Comment by Dr. Krishna Kumari Challa on May 18, 2021 at 11:37am

Collective intelligence can be predicted and quantified, new study finds

In order to address issues ranging from climate change to developing complex technologies and curing diseases, science relies on collective intelligence, or the ability of a group to work together and solve a range of problems that vary in complexity.

To better understand how to measure and predict collective intelligence, researchers used meta-analytic methods to evaluate data collected in 22 studies, including 5,349 individuals in 1,356 groups, and found strong support for a general factor of collective intelligence (CI). Furthermore, the data demonstrated that group collaboration processes were about twice as important for predicting CI than individual skill, and that group composition, including the proportion of women in a group and group member social perceptiveness, are also significant predictors of CI.

The paper, "Quantifying Collective Intelligence in Human Groups," by Christoph Riedl (Northeastern University), Young Ji Kim (University of California, Santa Barbara), Pranav Gupta (Carnegie Mellon University), Thomas W. Malone (MIT Sloan School of Management), and Williams Woolley, Anita (Carnegie Mellon University) will be published in Proceedings of the National Academy of Sciences of the United States of America.

Christoph Riedl el al., "Quantifying collective intelligence in human groups," PNAS (2021). www.pnas.org/cgi/doi/10.1073/pnas.2005737118

https://phys.org/news/2021-05-intelligence-quantified.html?utm_sour...

Comment by Dr. Krishna Kumari Challa on May 18, 2021 at 9:24am

Mothers can influence offspring's height, lifespan and disease risk through mitochondria

Mitochondria—the 'batteries' that power our cells—play an unexpected role in common diseases such as type 2 diabetes and multiple sclerosis, concludes a study of over 350,000 people.

The study, published today in Nature Genetics, found that genetic variants in the DNA of mitochondria could increase the risk of developing these conditions, as well influencing characteristics such as height and lifespan.

There was also evidence that some changes in mitochondrial DNA were more common in people with Scottish, Welsh or Northumbrian genetic ancestry, implying that mitochondrial DNA and nuclear DNA (which accounts for 99.9% of our genetic make-up) interact with each other.

Almost all of the DNA that makes up the human genome—the body's 'blueprint' - is contained within the nuclei of our cells. Among other functions, nuclear DNA codes for the characteristics that make us individual as well as for the proteins that do most of the work in our bodies.

Our cells also contain mitochondria, often referred to as 'batteries', which provide the energy for our cells to function. They do this by converting the food that we eat into ATP, a molecule capable of releasing energy very quickly. Each of these mitochondria is coded for by a tiny amount of 'mitochondrial DNA'. Mitochondrial DNA makes up only 0.1% of the overall human genome and is passed down exclusively from mother to child.

While errors in mitochondrial DNA can lead to so-called mitochondrial diseases, which can be severely disabling, until now there had been little evidence that these variants can influence more common diseases. Several small-scale studies have hinted at this possibility, but scientists have been unable to replicate their findings.

Among those factors found to be influenced by mitochondrial DNA are: type 2 diabetes, multiple sclerosis, liver and kidney function, blood count parameters, life span and height. While some of the effects are seen more extremely in patients with rare inherited mitochondrial diseases—for example, patients with severe disease are often shorter than average—the effect in healthy individuals tends to be much subtler, likely accounting for just a few millimetres' height difference, for example.

There are several possible explanations for how mitochondrial DNA exerts its influence. One is that changes to mitochondrial DNA lead to subtle differences in our ability to produce energy. However, it is likely to be more complicated, affecting complex biological pathways inside our bodies—the signals that allow our cells to operate in a coordinated fashion.

Yonova-Doing, E et al. An atlas of mitochondrial DNA genotype-phenotype associations in the UK Biobank. Nature Genetics (2021). DOI: 10.1038/s41588-021-00868-1

https://phys.org/news/2021-05-mothers-offspring-height-lifespan-dis...

Comment by Dr. Krishna Kumari Challa on May 17, 2021 at 11:20am

Human Impact on Earth Is Shrinking an Entire Layer of The Atmosphere, Scientists Warn

Our world is hugged by complex layers of gases that make up the atmosphere. They protect and nurture all life as we know it. Now, we're shrinking an entire one of those layers – the stratosphere – thanks to the profound impacts we are having on our planet.

An alarming new study has found that the thickness of the stratosphere has already shrunk by 400 meters (1,312 feet) since 1980. While local decreases in the stratosphere's thickness have previously been reported, this is the first examination of this phenomenon on a global scale.

Greenhouse gas-induced warming in the troposphere is causing it to expand and squash the stratosphere above it, they explain. On top of this, the addition of CO₂ into the stratosphere itself is causing its combination of gasses to cool and huddle closer together (the opposite effect they have on the troposphere) – shrinking the entire layer.

In a plausible climate change scenario, our planet's stratosphere could lose 4 percent of its vertical extension (1.3 km [0.8 mi]) from 1980 to 2080.

https://iopscience.iop.org/article/10.1088/1748-9326/abfe2b

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