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Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 6:26am

Voyager spacecraft detect new type of solar electron burst

In a new study, a team of physicists led by the University of Iowa report the first detection of bursts of cosmic ray electrons accelerated by shock waves originating from major eruptions on the sun. The detection, made by instruments onboard both the Voyager 1 and Voyager 2 spacecraft, occurred as the Voyagers continue their journey outward through interstellar space, thus making them the first craft to record this unique physics in the realm between stars.

These newly detected electron bursts are like an advanced guard accelerated along magnetic field lines in the interstellar medium; the electrons travel at nearly the speed of light, some 670 times faster than the shock waves that initially propelled them. The bursts were followed by plasma wave oscillations caused by lower-energy electrons arriving at the Voyagers' instruments days later—and finally, in some cases, the shock wave itself as long as a month after that.

The shock waves emanated from coronal mass ejections, expulsions of hot gas and energy that move outward from the sun at about one million miles per hour. Even at those speeds, it takes more than a year for the shock waves to reach the Voyager spacecraft, which have traveled further from the sun (more than 14 billion miles and counting) than any human-made object.

Astronomical Journal (2020). DOI: 10.3847/1538-3881/abc337

https://phys.org/news/2020-12-voyager-spacecraft-solar-electron.htm...

Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 6:23am

Climate change is resulting in profound, immediate and worsening health impacts, over 120 researchers say

This year's annual report of The Lancet Countdown on Health and Climate Change, released today, presents the latest data on health impacts from a changing climate.

Among its results, the report found there were 296,000 heat-related premature deaths in people over 65 years in 2018 (a 54% increase in the last two decades), and that global yield potential for major crops declined by 1.8–5.6% between 1981 and 2019.

based on current population data, 145 million people face potential inundation with global mean sea-level rise of one metre. This jumps to 565 million people with a five metre sea-level rise.

Unless urgent action is taken, the health consequences of climate change will worsen. A globally coordinated effort tackling COVID-19 and climate change in unison is vital, and will mean a triple win: better public health, a more sustainable economy and environmental protection.

https://theconversation.com/climate-change-is-resulting-in-profound...

Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 6:17am

Common pipe alloy can form cancer-causing chemical in drinking water

Rusted iron pipes can react with residual disinfectants in drinking water distribution systems to produce carcinogenic hexavalent chromium in drinking water, reports a study by engineers .

Chromium is a metal that occurs naturally in the soil and groundwater. Trace amounts of trivalent chromium eventually appear in the drinking water and food supply and are thought to have neutral effects on health. Chromium is often added to iron to make it more resistant to corrosion.

Certain chemical reactions can change chromium atoms into a hexavalent form that creates cancer-causing genetic mutations in cells.

Cheng Tan et al, Hexavalent Chromium Release in Drinking Water Distribution Systems: New Insights into Zerovalent Chromium in Iron Corrosion Scales, Environmental Science & Technology (2020). DOI: 10.1021/acs.est.0c03922

https://phys.org/news/2020-12-common-pipe-alloy-cancer-causing-chem...

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Engineers invent fast and safe way to store natural gas for useful ...

applications

Natural gas is the cleanest of all fossil fuels, but storing it safely and affordably remains a challenge. Now, engineers from the National University of Singapore (NUS) have devised a method to convert natural gas into a non-explosive solid that can be easily stored and transported. Using a novel, low-toxicity additive mixture they formulated, the conversion can be completed in just 15 minutes—the fastest time so far.

The NUS team worked on a process of converting natural gas into a sold form known as gas hydrates, or combustible ice, which consists of molecules of natural gas trapped in "cages" formed by water molecules. In fact, nature stores natural gas this way, but the process is extremely slow. Other researchers have previously managed to speed it up artificially, but they resorted to using highly toxic additives which are unsafe for both the environment and personnel involved.

The new additive mixture formulated by the NUS researchers contains L-tryptophan, well known as an essential amino acid in people's diet. This muscle-building amino acid can also greatly speed up the caging of natural gas into solid hydrate. The NUS formulation produces the fastest reaction rate to date—more than twice as fast as existing standards—while being less toxic and safer to handle.

Gaurav Bhattacharjee et al. Ultra-rapid uptake and the highly stable storage of methane as combustible ice, Energy & Environmental Science (2020). DOI: 10.1039/D0EE02315A

Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 6:14am

Medicine-carriers made from human cells can cure lung infections

Scientists used human white blood cell membranes to carry two drugs, an antibiotic and an anti-inflammatory, directly to infected lungs in mice.

The nano-sized drug delivery method developed successfully treated both the bacterial growth and inflammation in the mice's lungs. The study, recently published in Communications Biology, shows a potential new strategy for treating infectious diseases, including COVID-19.

If a doctor simply gives two drugs to a patient, they don't go directly to the lungs. They circulate in the whole body, so potentially there's a lot of toxicity. Instead, researchers can load the two types of drugs into these vesicles that specifically target the lung inflammation.

The research team has developed a method to essentially peel the membrane from neutrophils, the most common type of white blood cells that lead the body's immune system response. Once emptied, these membranes can be used as nanovesicles, tiny empty sacks only 100 to 200 nanometers wide, which scientists can then fill with medicine.

These nanovesicles retain some of the properties of the original white blood cells, so when they are injected into a patient, they travel directly to the inflamed area just as the cells would normally, but these nanovesicles carry the medicines that the scientists implanted to attack the infection.

Jin Gao et al, Co-delivery of resolvin D1 and antibiotics with nanovesicles to lungs resolves inflammation and clears bacteria in mice, Communications Biology (2020). DOI: 10.1038/s42003-020-01410-5

https://phys.org/news/2020-12-medicine-carriers-human-cells-lung-in...

Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 6:06am

Scientists predict 'optimal' organism stress levels

Scientists have created an evolutionary model to predict how animals should react in stressful situations.

Almost all organisms have fast-acting stress responses, which help them respond to threats—but being stressed uses energy, and chronic stress can be damaging.

The new study—by an international team including the University of Exeter—suggests most animals remain stressed for longer than is optimal after a stress-inducing incident.

The reasons for this are not clear, but one possibility is that there is a limit to how quickly the body can remove stress hormones from circulation.

So scientists have created one of the first mathematical models to understand how organisms have evolved to deal with stressful events. It combines existing research on stress physiology in a variety of organisms with analysis of optimal responses that balance the costs and benefits of stress.

We know stress responses vary hugely between different species and even among individuals of the same species—as we see in humans. This  study is a step towards understanding why stress responses are so variable.

The researchers define stress as the process of an organism responding to "stressors" (threats and challenges in their environment), including both detection and the stress response itself. A key point highlighted in the study is the importance of how predictable threats are.

The model suggests that an animal living in a dangerous environment should have a high "baseline" stress level, while an animal in a safer environment would benefit from being able to raise and reduce stress levels rapidly.

This approach reveals environmental predictability and physiological limits as key factors shaping the evolution of stress responses.

Barbara Taborsky et al, Towards an Evolutionary Theory of Stress Responses, Trends in Ecology & Evolution (2020). DOI: 10.1016/j.tree.2020.09.003

https://phys.org/news/2020-12-scientists-optimal-stress.html?utm_so...

Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 5:48am

**How plants compete for underground real estate affects climate change and food production

You might have observed plants competing for sunlight—the way they stretch upwards and outwards to block each other's access to the sun's rays—but out of sight, another type of competition is happening underground. In the same way that you might change the way you forage for free snacks in the break room when your colleagues are present, plants change their use of underground resources when they're planted alongside other plants.

In a paper published today in Science, an international team of researchers  sheds light on the underground life of plants. Their research used a combination of modeling and a greenhouse experiment to discover whether plants invest differently in root structures when planted alone versus when planted alongside a neighbour.

Plants make two different types of roots: fine roots that absorb water and nutrients from the soil, and coarse transportation roots that transport these substances back to the plant's center. Plant "investment" in roots involves both the total volume of roots produced and the way in which these roots are distributed throughout the soil. A plant could concentrate all of its roots directly beneath its shoots, or it could spread its roots out horizontally to forage in the adjacent soil—which risks competition with the roots of neighboring plants.

The team's model predicted two potential outcomes for root investment when plants find themselves sharing soil. In the first outcome, the neighboring plants "cooperate" by segregating their root systems to reduce overlap, which leads to producing less roots overall than they would if they were solitary. In the second outcome, when a plant senses reduced resources on one side due to the presence of a neighbor, it shortens its root system on that side but invests more in roots directly below its stem.

Natural selection predicts this second scenario, because each plant acts to increase its own fitness, regardless of how those actions impact other individuals. If plants are very close together, this increased investment in root volume, despite segregation of those roots, could result in a tragedy of the commons, whereby the resources (in this case, soil moisture and nutrients) are depleted.

When this was tested on pepper plants, the team discovered that the outcome depends on how close a pair of plants are to each other. If planted very close together, plants will be more likely to heavily invest in their root systems to try to outcompete each other for finite underground resources; if they are planted further apart, they will likely invest less in their root systems than a solitary plant would.

Specifically, they found that when planted near others, pepper plants increased investment in roots locally and reduced how far they stretched their roots horizontally, to reduce overlap with neighbors. There was no evidence for a "tragedy of the commons" scenario, since there was no difference in the total root biomass or relative investment in roots compared to aboveground structures (including the number of seeds produced per plant) for solitary versus co-habiting plants.

 C. Cabal el al., "The exploitative segregation of plant roots," Science (2020). science.sciencemag.org/cgi/doi … 1126/science.aba9877

https://phys.org/news/2020-12-underground-real-estate-affects-clima...

Comment by Dr. Krishna Kumari Challa on December 4, 2020 at 5:42am

Physicists capture the sound of a 'perfect' fluid

For physicists, a perfect flow is more specific, referring to a fluid that flows with the smallest amount of friction, or viscosity, allowed by the laws of quantum mechanics. Such perfectly fluid behaviour is rare in nature, but it is thought to occur in the cores of neutron stars and in the soupy plasma of the early universe.

Now physicists have created a perfect fluid in the laboratory, and listened to how sound waves travel through it. The recording is a product of a glissando of sound waves that the team sent through a carefully controlled gas of elementary particles known as fermions. The pitches that can be heard are the particular frequencies at which the gas resonates like a plucked string.

The researchers analyzed thousands of sound waves traveling through this gas, to measure its "sound diffusion," or how quickly sound dissipates in the gas, which is related directly to a material's viscosity, or internal friction.

Surprisingly, they found that the fluid's sound diffusion was so low as to be described by a "quantum" amount of friction, given by a constant of nature known as Planck's constant, and the mass of the individual fermions in the fluid.

This fundamental value confirmed that the strongly interacting fermion gas behaves as a perfect fluid, and is universal in nature. The results, published today in the journal Science, demonstrate the first time that scientists have been able to measure sound diffusion in a perfect fluid.

Scientists can now use the fluid as a model of other, more complicated perfect flows, to estimate the viscosity of the plasma in the early universe, as well as the quantum friction within neutron stars—properties that would otherwise be impossible to calculate. Scientists might even be able to approximately predict the sounds they make.

"Universal sound diffusion in a strongly interacting Fermi gas" Science (2020). science.sciencemag.org/cgi/doi … 1126/science.aaz5756

https://phys.org/news/2020-12-physicists-capture-fluid.html?utm_sou...

Comment by Dr. Krishna Kumari Challa on December 3, 2020 at 12:01pm

Organic Molecules

Comment by Dr. Krishna Kumari Challa on December 3, 2020 at 11:30am

Peer Review: Implementing a "publish, then review" model of publishing

From July 2021 eLife will only review manuscripts already published as preprints, and will focus its editorial process on producing public reviews to be posted alongside the preprints.

https://elifesciences.org/articles/64910?utm_source=content_alert&a...

Comment by Dr. Krishna Kumari Challa on December 3, 2020 at 11:23am

Engineering a viral solution to cancer

Virotherapy is a treatment using biotechnology to convert viruses into therapeutic agents by reprogramming viruses to treat diseases. There are three main branches of virotherapy: anti-cancer oncolytic viruses,

While doctors can successfully treat some types of skin cancer at the surface with human-engineered viruses, scientists have yet to find a way to inject these types of viruses to seek and destroy other cancers in the body, such as lung cancer.

But medical researchers at Case Western Reserve University and Emory University are reporting remarkable success in eliminating human cancer cells in mouse models by injecting a modified strain of adenovirus into the bloodstream.

Oncolytic viruses, some found in nature and others modified in the laboratory, are a class of viruses that can infect and kill tumor cells, reproducing efficiently in the tumor without harming healthy cells.

These Scientists performed cryo-electron microscopy and structural modeling to visualize the engineered adenovirus generated by other scientists. Each change in the engineered virus allowed it to evade a particular defense by the body.

 tweaked the adenovirus (named the Ad5-3M virus, indicating three different engineered mutations) to successfully skirt three antiviral immune responses.

Those three responses were:

• Binding: Factors in the blood itself bind the virus and try to clear it through the liver.

• Cytokine storm: Flexible loops on the structure of the virus interact with the body’s host cells, triggering a massive and possibly deadly release of a group of proteins or peptides called cytokines.

• Pathogen clearance: Multiple components of the immune system act in a concerted way to clear pathogens from the body.

https://thedaily.case.edu/engineering-a-viral-solution-to-cancer/

https://researchnews.cc/news/3902/Engineering-a-viral-solution-to-c...

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