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Comment by Dr. Krishna Kumari Challa on February 5, 2022 at 9:01am

Three COVID-19 exposures needed for broad immunity

The immune system develops a high-quality antibody response after three encounters with the coronavirus spike protein. These antibodies are also capable of neutralizing omicron efficiently. This applies to people who are triple-vaccinated, to those having recovered and then received two vaccinations and to double-vaccinated individuals who have experienced a breakthrough infection. These are results of a study which tracked the antibodies of vaccinated and recovered individuals for two years.

Answers to the question how the immune systems can be "educated" to battle omicron and other immune escape variants of the virus are provided by a team of researchers. As they report in Nature Medicine, a total of three exposures to the viral spike protein leads to production of virus neutralizing antibodies not only in high quantity, but also high quality. These high-quality antibodies bind to the viral spike protein more vigorously and are also capable of effectively fighting the omicron variant. This applies to triple-vaccinated people, to people who have recovered from COVID-19 and then had two vaccinations, and to double-vaccinated people who then had a breakthrough infection.

In the new study the team now defined several parameters in the blood of study participants: the concentration of antibodies to the viral spike protein, the binding strength of these antibodies, and their ability to neutralize infection of SARS-CoV-2 variants in cell culture. For estimating the extent of protective immunity, the latter two parameters are particularly important. The study revealed that the ability of the immune system to neutralize the virus correlates only weakly with the antibody titer. Rather, it was critical how effectively these antibodies bind to the virus and thus disable infection.

As predicted from its many mutations, omicron exhibited the most pronounced evasion from neutralizing antibodies compared to all other viral variants tested. "For omicron, you need considerably more and better antibodies to prevent infection" . The researchers developed a new virus neutralization test, which allowed them to analyze antibodies in many serum samples and different variants of the virus at high throughput rates. A new finding of this study is that people require three separate exposures to the spike protein to build up high-level neutralizing activity against all viral variants, including omicron.

As the scientists report, various constellations are possible for these three spike encounters. Triple-vaccinated people without prior SARS-CoV-2 infection had almost the same titer and quality of neutralizing antibodies against omicron as vaccinated convalescents or people who had a breakthrough infection with delta or omicron.

In all cases, the neutralization activity reached similarly high levels and this was paralleled by an increased binding strength of the antibodies.

Paul R. Wratil et al, Three exposures to the spike protein of SARS-CoV-2 by either infection or vaccination elicit superior neutralizing immunity to all variants of concern, Nature Medicine (2022). DOI: 10.1038/s41591-022-01715-4

Nina Koerber et al, Dynamics of spike-and nucleocapsid specific immunity during long-term follow-up and vaccination of SARS-CoV-2 convalescents, Nature Communications (2022). DOI: 10.1038/s41467-021-27649-y

https://researchnews.cc/news/11427/Three-COVID-19-exposures-needed-...

Comment by Dr. Krishna Kumari Challa on February 4, 2022 at 12:04pm

There's a Bunch of Bacteria exchanging genetic material  in Your Gut, And It's Wilder Than We Thought

The human gut is the host of a rampant microscopic orgy. To survive, the microbes in our digestive tract are having 'sex' with each other on a regular basis, all in the name of swapping secrets on how to survive deadly doses of antibiotics.

A team of researchers from the University of Illinois at Urbana-Champaign and University of California Riverside has now learned just how far this bacterial bump-and-grind goes, finding exchanges that go beyond what we knew previously.

Bacteria, of course, don't have genitals, but technically 'sex' in biology refers to any process that exchanges genetic material.

By forming a 'temporary union' with another bacterium in our gut, a microbe can therefore transfer its genes to another – it doesn't even have to be the same species.

All the microbe has to do is stick out a tube, called a pilus, and attach itself to another cell, shooting off a transferable package of DNA called a mobile genetic element when it's ready.

The discovery of bacterial sex was made over 70 years ago, when scientists realized this horizontal gene transfer was how microbes were sharing resistance genes for certain antibiotics, thereby spreading antibiotic resistance.

More recently, it's become clear that bacterial sex doesn't just occur when microbes are under attack. It happens all the time, and it's probably part of what keeps our microbiome fit and healthy.

https://www.cell.com/cell-reports/fulltext/S2211-1247(21)01664-8?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2211124721016648%3Fshowall%3Dtrue

https://www.sciencealert.com/there-are-a-bunch-of-bacteria-having-s...

Comment by Dr. Krishna Kumari Challa on February 4, 2022 at 11:55am

CAR-T cells hold cancer at bay

A last-resort cancer treatment called CAR-T cell therapy has kept two people leukaemia-free for 12 years. “We can now conclude that CAR T cells can actually cure patients with leukaemia,” says physician and study author Carl June. CAR-T cell therapies involve removing immune cells called T cells from a person with cancer, and genetically altering them so that they produce proteins — called chimeric antigen receptors, or CARs — that recognize cancer cells. The cells are then reinfused into the person, in the hope that they will seek out and destroy tumours. But the therapy is expensive, risky and technically demanding, and doesn’t work for everyone.

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First COVID human challenge trial

Initial results from the first COVID-19 human challenge study show that healthy, young people developed no or mild symptoms. Such trials intentionally expose participants to a disease, providing a unique opportunity to study viral infections in detail from start to finish — but they are controversial because of the risks they pose to volunteers. The UK study of 34 individuals, aged 18–30, shows that such trials can be done safely, say scientists, and lays the groundwork for more in-depth studies of vaccines, antivirals and immune responses to SARS-CoV-2 infection.

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Direct evidence of two types of water

Water is unlike most other liquids on Earth: it has at least 66 weird properties, including high surface tension, high heat capacity, high melting and boiling points and low compressibility. Some chemists have come to think of it as not being one liquid at all, but two distinct liquid phases that coexist in a mixture. Now, physicists might have made the first direct observation of the transformation between the two ..., in supercold water mixed with trehalose, a natural antifreeze that keeps the liquid from freezing.

Comment by Dr. Krishna Kumari Challa on February 4, 2022 at 10:26am

How to find a planet you can’t see

Comment by Dr. Krishna Kumari Challa on February 3, 2022 at 11:28am

Scientists engineer new material that can absorb and release enormous amounts of energy

A team of researchers  recently announced in the Proceedings of the National Academy of Sciences that they had engineered a new rubber-like solid substance that has surprising qualities. It can absorb and release very large quantities of energy. And it is programmable. Taken together, this new material holds great promise for a very wide array of applications, from enabling robots to have more power without using additional energy, to new helmets and protective materials that can dissipate energy much more quickly.

A hypothetical rubber band is made out of a new metamaterial—a substance engineered to have a property not found in naturally occurring materials—that combines an elastic, rubber-like substance with tiny magnets embedded in it. This new "elasto-magnetic" material takes advantage of a physical property known as a phase shift to greatly amplify the amount of energy the material can release or absorb.

A phase shift occurs when a material moves from one state to another: think of water turning into steam or liquid concrete hardening into a sidewalk. Whenever a material shifts its phase, energy is either released or absorbed. And phase shifts aren't just limited to changes between liquid, solid and gaseous states—a shift can occur from one solid phase to another. A phase shift that releases energy can be harnessed as a power source.

 Xudong Liang et al, Phase-transforming metamaterial with magnetic interactions, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2118161119

https://phys.org/news/2022-02-scientists-material-absorb-enormous-a...

Comment by Dr. Krishna Kumari Challa on February 3, 2022 at 11:25am

New insights about the toxicity of smoke produced by home stoves and power plants

The color of smoke coming out from chimneys can vary greatly based on its source and how it is produced. For instance, small coal or biomass stoves typically release dense, black smoke, while power generation plants produce lighter-colored plumes of smoke.

While these color differences are known to be linked to the different aerosols contained in smoke, so far not many studies have closely examined the major components of these aerosols and their effects on health. Researchers at Fudan University, Tsinghua University, and the Hong Kong Polytechnic University recently published a paper in Nature Energy outlining new interesting findings about the levels of toxicity of aerosols originating from different combustion sources, such as stoves in residential homes and coal-fired power plants (CFPPs).

"Differences in the color of smoke coming out from distinct chimneys can indicate different aerosols in plumes. "A crucial question is, are the major components of aerosols from these emission sources different, and can they have different health impacts? To investigate this, we collected the aerosols from large scale CFPPs and common household stoves burning wood and coal."

When researchers  analyzed the aerosols produced by CFPPs and common household stoves in the lab, they found that they had significant chemical differences. Interestingly, those emitted by household stoves primarily contained carbonaceous matter resulting from the incomplete combustion of coal or biomass material. On the other hand, large-scale powerplants that rely on efficient boilers could attain the complete combustion of fuels. This resulted in better pollution control metrics and a lower number of aerosols containing inorganic materials, such as transition and heavy metals.

In the second part of their study, the researchers used real cells from human lungs (i.e., pulmonary cells) to determine the toxicity of the inhalable particulate matter (PM) produced by household stoves and CFPPs. They specifically examined the generation of intracellular reactive oxygen species (ROS) prompted by the PM, as well as cell viability and toxicity.

Combining the chemical data with their previous information on chemical toxicity, they conducted a further aerosol toxic experiment with respiratory cells. In this experiment, they demonstrated that the toxicity of aerosols emitted from household coal/wood burning is more than 10 times higher than that from large scale coal-fired power plants.

Di Wu et al, Toxic potency-adjusted control of air pollution for solid fuel combustion, Nature Energy (2022). DOI: 10.1038/s41560-021-00951-1

https://techxplore.com/news/2022-02-insights-toxicity-home-stoves-p...

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Comment by Dr. Krishna Kumari Challa on February 3, 2022 at 9:34am

World-Record 'Megaflash' of Lightning Stretched for Almost 500 Miles

A jaw-dropping lightning megaflash that snaked across three states in the southern US just won a world record.

A megaflash is not your standard cloud-to-ground lightning bolt. It's an enormous electric zigzag that travels from one electrified cloud to the next, almost instantaneously.

https://www.sciencealert.com/space-images-show-700-km-lightning-meg...

Comment by Dr. Krishna Kumari Challa on February 3, 2022 at 9:23am

Almost No Coral Reefs in The World Will Be Safe at 1.5°C Warming, Scientists Warn

Coral reefs have long been regarded as one of the earliest and most significant ecological casualties of global warming.

In new research published in the journal PLOS Climate, we found that the future of these tropical ecosystems – thought to harbor more species than any other – is probably worse than anticipated.

Climate change is causing more frequent marine heatwaves worldwide. Corals have adapted to live in a specific temperature range, so when ocean temperatures are too hot for a prolonged period, corals can bleach – losing the colorful algae that live within their tissue and nourish them via photosynthesis – and may eventually die.

Across the tropics, mass bleaching and die-offs have gone from being rare to a somewhat regular occurrence as the climate has warmed. More frequent heatwaves mean that the time corals have to recover is getting shorter.

In a 2018 report, the Intergovernmental Panel on Climate Change predicted that 1.5°C of global warming would cause between 70 and 90 percent of the world's coral reefs to disappear.

Now, with models capable of examining temperature differences between coral reefs one kilometer apart, our team found that at 1.5°C of warming, which the world is predicted to reach in the early 2030s without drastic action to limit greenhouse gas emissions, 99 percent of the world's reefs will experience heatwaves that are too frequent for them to recover.

That would spell catastrophe for the thousands of species that depend on coral reefs, as well as the roughly one billion people whose livelihoods and food supply benefits from coral reef biodiversity.

Climate change is already degrading coral reefs globally. Now we know that protecting the last remaining temperature refuges will not work on its own. Slashing greenhouse gas emissions this decade is the best hope for saving what remains. 

https://journals.plos.org/climate/article?id=10.1371/journal.pclm.0...

https://theconversation.com/safe-havens-for-coral-reefs-will-be-alm...

Comment by Dr. Krishna Kumari Challa on February 3, 2022 at 9:15am

Uranus And Neptune Aren't The Same Color. A New Study Could Finally Explain Why

Uranus and Neptune are the most twin-like of all the planets in the Solar System. They are almost the same size and mass, have similar compositions and structures, even similar rotation rates.

Which makes one glaring difference quite perplexing. Neptune is a fetching shade of azure, with visible swirling storms. Uranus is more of a featureless, delicate pale teal. If the two planets are so similar, whence the difference in their methane-based blues?

New research, uploaded to preprint server arXiv and awaiting peer review, claims to have found an answer. According to a team led by planetary physicist Patrick Irwin of the University of Oxford in the UK, an extended layer of haze dilutes the hue of Uranus, resulting in a paler orb compared to its more distant twin; fraternal, not identical.

Uranus and Neptune, according to our measurements of the two planets, are structured very similarly. A small, rocky core is surrounded by a mantle of water, ammonia, and methane ices; next, a gaseous atmosphere consisting primarily of hydrogen, helium and methane; and finally the upper atmosphere, including cloud tops. But that atmosphere isn't homogeneous; rather, it is thought to be layered, like every other atmosphere in the Solar System.

Researchers analyzed visible and near-infrared observations of the two planets to generate new models of the atmospheric layers. They managed to find models that replicate the observations very well, including the storms on Neptune and the paler shade of Uranus.

In their models, both planets have a layer of photochemical haze. This occurs when ultraviolet radiation from the Sun breaks down aerosol particles in the atmosphere, producing haze particles. It's a common process, seen on Venus, Earth, Saturn, Jupiter, dwarf planet Pluto, and moons Titan and Triton.

The researchers called this the Aerosol-2 layer, and on both planets it seems to be a source of the cloud seeds that condense into methane ice at the lower boundary and snows deeper into the atmosphere. And on Uranus, this layer seems to be twice as opaque as it is on Neptune – and this is why the two planets look different.

https://arxiv.org/abs/2201.04516

https://www.sciencealert.com/we-might-finally-know-why-uranus-and-n...

Comment by Dr. Krishna Kumari Challa on February 3, 2022 at 8:54am

Plant flowering also influences animals for which pollen, nectar, fruits and seeds are important resources… "

The effects of an early flowering season could therefore ripple through ecosystems, causing what scientists call ecological (or phenological) mismatch – when the lifecycles of species that have evolved together and depend on each other fall out of sync.

This can lead to disrupted migration patterns, species starvation, outbreaks of pests and disease, and even extinction.

England isn't the only nation that has to worry about its flowering season. Earlier spring temperatures are being recorded throughout the world, both in the northern hemisphere and the southern hemisphere.

Last year, in Japan, cherry blossoms bloomed the earliest they have in 1,200 years.

Even with just a few centuries of data, however, the result of our emissions is clear to see. Climate change is winding up our Spring clock, and we don't know if we can wind it back again.

https://royalsocietypublishing.org/doi/10.1098/rspb.2021.2456

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