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Comment by Dr. Krishna Kumari Challa on April 23, 2021 at 10:47am

Plastic: What we eat and breathe

Take a deep breath, drink a glass of water, eat a snack. If you do any of these things, it's likely that you are also inhaling and ingesting tiny particles of plastic, as much as a credit card's weight each week. Plastic pollution is everywhere, including in our bodies.

The industry also peddled the myth that recycling is the solution, even though it has long known that this is not economically viable. Today, we pay for recycling infrastructure and dutifully sort our waste into bins, even though only 10% of all plastic is recycled.

Individuals don't start pollution. The industry does. We must demand that they stop it.

https://phys.org/news/2021-04-plastic.html?utm_source=nwletter&...

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Comment by Dr. Krishna Kumari Challa on April 23, 2021 at 9:10am

A novel optical physics method to measure the expansion of the univ...

Quasars are extraordinarily distant celestial objects that throw off a massive amount of light, and astrophysicists use them to probe cosmological theories.

Comment by Dr. Krishna Kumari Challa on April 23, 2021 at 9:08am

Eliminating resistant bacteria with nanoparticles

Novel nanoparticles developed by researchers  detect multi-resistant bacteria hiding in body cells and kill them. The scientists' goal is to develop an antibacterial agent that is effective where conventional antibiotics remain ineffective.

In the arms race "mankind against bacteria," bacteria are currently ahead of us. Our former miracle weapons, antibiotics, are failing more and more frequently when germs use tricky maneuvers to protect themselves from the effects of these drugs. Some species even retreat into the inside of human cells, where they remain "invisible" to the immune system. These particularly dreaded pathogens include multi-resistant staphylococci (MRSA), which can cause life-threatening diseases such as sepsis or pneumonia.

In order to track down the germs in their hideouts and eliminate them, a team of researchers  is now developing nanoparticles that use a completely different mode of action from conventional antibiotics: While antibiotics have difficulty in penetrating human cells, these nanoparticles can penetrate the membrane of affected cells. Once there, they can fight the bacteria.

They used cerium oxide, a material with antibacterial and anti-inflammatory properties in its nanoparticle form. The researchers combined the cerium oxide with a bioactive ceramic material known as bioglass and synthesized nanoparticle hybrids from the two materials.

In cell culture and using electron microscopy, they investigated the interactions between the hybrid nanoparticles, human cells and bacteria. When the scientists treated cells infected with bacteria with the nanoparticles, the bacteria inside the cells began to dissolve. However, if the researchers specifically blocked the uptake of the hybrid particles into the cells, the antibacterial effect was gone.

The particles' exact mode of action is not yet fully understood. It has been shown that other metals also have antimicrobial effects. However, cerium is less toxic to human cells than, for instance, silver. Scientists currently assume that the nanoparticles affect the cell membrane of the bacteria, creating reactive oxygen species that lead to the destruction of the germs. Since the cell membrane of human cells is structured differently than that of bacteria, our cells are not affected by this process.

The researchers think that resistance is less likely to develop against a mechanism of this kind. 

Martin T. Matter et al. Inorganic nanohybrids combat antibiotic-resistant bacteria hiding within human macrophages, Nanoscale (2021). DOI: 10.1039/d0nr08285f

https://phys.org/news/2021-04-resistant-bacteria-nanoparticles.html...

Comment by Dr. Krishna Kumari Challa on April 23, 2021 at 9:02am

New material could better protect soldiers, athletes and motorists

Soldiers, athletes, and motorists could lead safer lives thanks to a new process that could lead to more efficient and re-useable protection from shock and impact, explosion, and vibration, according to a new study.

Pressurized insertion of aqueous solutions into water-repellent nanoporous materials, such as zeolites and metal-organic frame works, could help to create high-performance energy absorbing systems.

An international research team experimented with hydrothermally stable zeolitic imidazolate frameworks (ZIFs) with a 'hydrophobic' cage-like molecular structure—finding that such systems are remarkably effective energy absorbers at realistic, high-rate loading conditions, and this phenomenon is associated with the water clustering and mobility in nanocages.

High-rate nanofluidic energy absorption in porous zeolitic frameworks, Nature Materials (2021). DOI: 10.1038/s41563-021-00977-6

https://phys.org/news/2021-04-material-soldiers-athletes-motorists....

Comment by Dr. Krishna Kumari Challa on April 23, 2021 at 8:33am

Toxic masculinity: Y chromosome contributes to a shorter lifespan in male flies

Males may have shorter lifespans than females due to repetitive sections of the Y chromosome that create toxic effects as males get older. These new findings appear in a study published April 22 in PLOS Genetics.

In humans and other species with XY sex chromosomes, females often live longer than males. One possible explanation for this disparity may be repetitive sequences within the genome. While both males and females carry these repeat sequences, scientists have suspected that the large number of repeats on the Y chromosome may create a "toxic y effect" that shortens males' lives.

To test this idea, researchers studied male fruit flies from the species Drosophila miranda, which have about twice as much repetitive DNA as females and a shorter lifespan. They showed that when the DNA is in its tightly packed form inside the cells of young male flies, the repeat sections are turned off. But as the flies age, the DNA assumes a looser form that can activate the repeat sections, resulting in toxic side effects.

The new study demonstrates that Y chromosomes that are rich in repeats are a genomic liability for males. The findings also support a more general link between repeat DNA and aging, which currently, is poorly understood. Previous studies in fruit flies have shown that when repeat sections become active, they impair memory, shorten the lifespan and cause DNA damage. This damage likely contributes to aging's physiological effects, but more research will be needed to uncover the mechanisms underlying repeat DNA's toxic effects.

Nguyen AH, Bachtrog D (2021) Toxic Y chromosome: Increased repeat expression and age-associated heterochromatin loss in male Drosophila with a young Y chromosome. PLoS Genet 17(4): e1009438. doi.org/10.1371/journal.pgen.1009438

https://phys.org/news/2021-04-toxic-masculinity-chromosome-contribu...

Comment by Dr. Krishna Kumari Challa on April 23, 2021 at 8:06am

Scientists glimpse signs of a puzzling state of matter in a superconductor

Unconventional superconductors contain a number of exotic phases of matter that are thought to play a role, for better or worse, in their ability to conduct electricity with 100% efficiency at much higher temperatures than scientists had thought possible—although still far short of the temperatures that would allow their wide deployment in perfectly efficient power lines, maglev trains and so on.

Now scientists have glimpsed the signature of one of those phases, known as pair-density waves or PDW, and confirmed that it's intertwined with another phase known as charge density wave (CDW) stripes—wavelike patterns of higher and lower electron density in the material.

Observing and understanding PDW and its correlations with other phases may be essential for understanding how superconductivity emerges in these materials, allowing electrons to pair up and travel with no resistance.

 H. Huang et al. Two-Dimensional Superconducting Fluctuations Associated with Charge-Density-Wave Stripes in La1.87Sr0.13Cu0.99Fe0.01O4, Physical Review Letters (2021). DOI: 10.1103/PhysRevLett.126.167001

https://phys.org/news/2021-04-scientists-glimpse-puzzling-state-sup...

Comment by Dr. Krishna Kumari Challa on April 23, 2021 at 5:57am

A statement of the Nobel Laureates on the occasion of World Leaders meet on climate. 27 Nobel Chemists and 22 Nobel Physicists are signatories of this letter demanding "Keep the Fossil Fuels in the Ground" .

Part 1

Nobel Laureates’ Statement to Climate Summit World Leaders: Keep  Fossil Fuels in the Ground 

As Nobel Laureates from peace, literature, medicine, physics, chemistry  and economic sciences, and like so many people around the globe, we are  seized by the great moral issue of our time: the climate crisis and  commensurate destruction of nature. 

Climate change is threatening hundreds of millions of lives, livelihoods across every  continent and is putting thousands of species at risk. The burning of fossil fuels – coal, oil, and gas – is by far the major contributor to climate change. 

We write today, on the eve of Earth Day 2021 and the Leaders’ Climate  Summit, hosted by President Biden, to urge you to act now to avoid a  climate catastrophe by stopping the expansion of oil, gas and coal. 

We welcome President Biden and the US government’s acknowledgement in the  Executive Order that “Together, we must listen to science and meet the moment.”  Indeed, meeting the moment requires responses to the climate crisis that will  define legacies. Qualifications for being on the right side of history are clear. 

For far too long, governments have lagged, shockingly, behind what  science demands and what a growing and powerful people-powered  movement knows: urgent action is needed to end the expansions of fossil  fuel production; phase out current production; and invest in renewable  energy.

Comment by Dr. Krishna Kumari Challa on April 23, 2021 at 5:56am

Part 2

The burning of fossil fuels is responsible for almost 80% of carbon dioxide  emissions since the industrial revolution. In addition to being the leading source of  emissions, there are local pollution, environmental and health costs associated with  extracting, refining, transporting and burning fossil fuels. These costs are often paid  by Indigenous peoples and marginalized communities. Egregious industry practices  have led to human rights violations and a fossil fuel system that has left billions of  people across the globe without sufficient energy to lead lives of dignity. 

For both people and the planet, continued support must be given to tackling climate  change through the United Nations Framework Convention on Climate Change and  its Paris Agreement. Failure to meet the Paris Agreement’s temperature limit of  1.5°C risks pushing the world towards catastrophic global warming. 

Yet, the Paris Agreement has no mention of oil, gas or coal. Meanwhile, the  fossil fuel industry continues to plan new projects. Banks continue to fund new  projects. According to the most recent United Nations Environment Programme  report, 120% more coal, oil, and gas will be produced by 2030 than is consistent  with limiting warming to 1.5°C. Efforts to meet the Paris Agreement and to reduce  demand for fossil fuels will be undermined if supply continues to grow.

Comment by Dr. Krishna Kumari Challa on April 23, 2021 at 5:55am

Part 3

The solution is clear: fossil fuels must be kept in the ground. 

Leaders, not industry, hold the power and have the moral responsibility to take bold  actions to address this crisis. We call on world leaders to work together in a spirit of  international cooperation to: 

• End new expansion of oil, gas and coal production in line with the best available science as outlined by the Intergovernmental Panel on Climate Change and United Nations Environment Program; 
• Phase out existing production of oil, gas and coal in a manner that is fair and equitable, taking into account the responsibilities of countries for climate change and their respective dependency on fossil fuels, and capacity to  transition; 
• Invest in a transformational plan to ensure 100% access to renewable energy globally, support dependent economies to diversify away from fossil fuels, and enable people and communities across the globe to flourish  through a global just transition. 

Fossil fuels are the greatest contributor to climate change. Allowing the  continued expansion of this industry is unconscionable. The fossil fuel system  is global and requires a global solution – a solution the Leaders’ Climate Summit  must work towards. And the first step is to keep fossil fuels in the ground. 

https://fossilfueltreaty.org/nobel-letter

Comment by Dr. Krishna Kumari Challa on April 22, 2021 at 11:27am

NASA Extracts Breathable Oxygen From Thin Martian Air

: NASA has logged another extraterrestrial first on its latest mission to Mars: converting carbon dioxide from the Martian atmosphere into pure, breathable oxygen, the U.S. space agency said on Wednesday.

The unprecedented extraction of oxygen, literally out of thin air on Mars, was achieved Tuesday by an experimental device aboard Perseverance, a six-wheeled science rover that landed on the Red Planet February 18 after a seven-month journey from Earth.

In its first activation, the toaster-sized instrument dubbed MOXIE, short for Mars Oxygen In-Situ Resource Utilisation Experiment, produced about 5 grams of oxygen, equivalent to roughly 10 minutes’ worth of breathing for an astronaut, NASA said.

The instrument works through electrolysis, which uses extreme heat to separate oxygen atoms from molecules of carbon dioxide, which accounts for about 95% of the atmosphere on Mars.

The remaining 5% of Mars’ atmosphere, which is only about 1% as dense Earth’s, consists primarily of molecular nitrogen and argon. Oxygen exists on Mars in negligible trace amounts.

Although the initial output was modest, the feat marked the first experimental extraction of a natural resources from the environment of another planet for direct use by humans.

https://www.reuters.com/article/space-exploration-mars-oxygen/nasa-...

https://science.thewire.in/spaceflight/nasa-extracts-breathable-oxy...

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