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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

Part 2

Comment by Dr. Krishna Kumari Challa on February 3, 2022 at 8:52am

Flowers in The UK Are Blooming a Whole Month Earlier Than They Did in The 1980s

For centuries, British flowers have been blooming like clockwork. A few months into spring, sometime around May or June, the nation bursts into color.

Since the early 1980s, however, hundreds of plants have grown out of sync with the seasons, which means they're also unraveling from the complicated tapestry of interactions that keep ecosystems sustainably functioning.

When analyzing the first blooms of 406 plant species from 1753 to 2019, researchers found a clear and worrisome shift.

On average, flowers in the UK are blooming almost a whole month earlier than they were before 1986. In 2019, the first mean flowering date was as early as April 2.

Obviously, not all plants bloom at the same time. Herbs and trees are the first to flower, sometime in mid-April. While shrubs take about a month longer to open up.

The whole timeline, however, has been pushed forward as the climate changes.

Today, human-caused global warming is progressing at a rapid and unprecedented rate, and it's impacting the very function of Earth's ecosystems.

Something as dependable as the changing of the seasons is no longer so. 

Early spring warming in the UK appears to be changing the amount of rain that falls and the snow that melts, and both of these factors are important when it comes to a budding flower.

If temperatures continue to rise, the authors worry there will be a further shift in first flowering dates, possibly starting March or even earlier.

This transition could lead some plants, including crops, to bud far too early, causing them to freeze or suffer frost damage.

"We do not know whether adaptive evolution will allow populations to reach new [optimum flowering timing] rapidly enough to keep pace with climate change.

Researchers fear these changes will lead to agricultural losses and extend the allergy season. But it's not just humans that will be impacted.

"The timing of plant flowering can affect their pollination, especially when insect pollinators are themselves seasonal, and determine the timing of seed ripening and dispersal.

Part 1

Comment by Dr. Krishna Kumari Challa on February 2, 2022 at 12:41pm

The Astounding Physics of N95 Masks

https://www.wired.com/story/the-physics-of-the-n95-face-mask/?utm_s...

Comment by Dr. Krishna Kumari Challa on February 2, 2022 at 12:34pm

World hits ten billion COVID vaccinations In little more than a year, ten billion doses of COVID-19 vaccines have been administered globally, in what has become the largest vaccination programme in history. Many nations began rolling out vaccines in late 2020 and early 2021. Since then, more than 60% of the world’s population — 4.8 billion people — is at least partially vaccinated with one of the more than 20 approved COVID-19 vaccines. “The world has never seen such rapid scale-up of a new life-saving technology,” says Amanda Glassman, with the Center for Global Development. But — as researchers warned last year when the first one billion doses had been administered — there are still huge inequities in access, with just 5.5% of people in low-income nations having received 2 doses. https://www.nature.com/articles/d41586-022-00285-2?utm_source=Natur...

Comment by Dr. Krishna Kumari Challa on February 2, 2022 at 12:24pm

WHO warns of COVID medical waste threat

The World Health Organization warned recently that the vast amount of waste produced in tackling the COVID-19 pandemic posed a threat to human and environmental health.

The tens of thousands of tonnes of extra medical waste had put a huge strain on healthcare waste management systems, the WHO said in a report.

The extra waste is "threatening human and environmental health and exposing a dire need to improve waste management practices", the UN health agency said.

As countries scrambled to get personal protective equipment (PPE) to cope with the crisis, less attention was paid to disposing of COVID-19 health care waste safely and sustainably, the WHO said.

The latest available data, from 2019, suggested that one in three healthcare facilities globally did not safely manage healthcare waste—and in the 46 least-developed countries, more than two in three facilities did not have a basic healthcare waste management service.

"This potentially exposes health workers to needle stick injuries, burns and pathogenic microorganisms, while also impacting communities living near poorly-managed landfills and waste disposal sites through contaminated air from burning waste, poor water quality or disease-carrying pests," the WHO said.

https://phys.org/news/2022-02-covid-medical-threat.html?utm_source=...

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