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Comment by Dr. Krishna Kumari Challa on April 22, 2021 at 10:27am

Flying a helicopter on Mars

Comment by Dr. Krishna Kumari Challa on April 22, 2021 at 10:15am

Microplastics affect global nutrient cycle and oxygen levels in the...

The effects of the steadily increasing amount of plastic in the ocean are complex and not yet fully understood. Scientists at GEOMAR Helmholtz Centre for Ocean Research Kiel have now shown for the first time that the uptake of microplastics by zooplankton can have significant effects on the marine ecosystem even at low concentrations. The study, published in the international journal Nature Communications, further indicates that the resulting changes may be responsible for a loss of oxygen in the ocean beyond that caused by global warming.

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Climate 'tipping points' need not be the end of the world

The disastrous consequences of climate "tipping points" could be averted if global warming was reversed quickly enough, new research suggests.

Comment by Dr. Krishna Kumari Challa on April 22, 2021 at 10:10am

Lifelong burden of high stress hormones in female baboons shortens life expectancy

Female baboons may not have bills to pay or deadlines to meet, but their lives are extremely challenging. They face food and water scarcity and must be constantly attuned to predators, illnesses and parasites, all while raising infants and maintaining their social status.

A new study appearing April 21 in Science Advances shows that female baboons with high life-long levels of glucocorticoids, the hormones involved in the 'fight or flight' response, have a greater risk of dying than those with lower levels.

Glucocorticoids are a group of hormones that help prepare the body for a challenge. While these hormones have many functions in the body, persistently high levels of glucocorticoids in the bloodstream can be a marker of stress.

Females with higher levels of glucocorticoids in their feces, either due to more frequent exposure to different types of challenges, or more intense stress responses, tended to die younger.

 F.A. Campos at University of Texas at San Antonio in San Antonio, TX el al., "Glucocorticoid exposure predicts survival in female baboons," Science Advances (2021). advances.sciencemag.org/lookup … .1126/sciadv.abf6759

https://phys.org/news/2021-04-lifelong-burden-higher-stress-hormone...

Comment by Dr. Krishna Kumari Challa on April 22, 2021 at 10:02am

New process makes 'biodegradable' plastics truly compostable

Biodegradable plastics have been advertised as one solution to the plastic pollution problem bedeviling the world, but today's "compostable" plastic bags, utensils and cup lids don't break down during typical composting and contaminate other recyclable plastics, creating headaches for recyclers. Most compostable plastics, made primarily of the polyester known as polylactic acid, or PLA, end up in landfills and last as long as forever plastics.

Scientists have now invented a way to make these compostable plastics break down more easily, with just heat and water, within a few weeks, solving a problem that has flummoxed the plastics industry and environmentalists.

The new process involves embedding polyester-eating enzymes in the plastic as it's made. These enzymes are protected by a simple polymer wrapping that prevents the enzyme from untangling and becoming useless. When exposed to heat and water, the enzyme shrugs off its polymer shroud and starts chomping the plastic polymer into its building blocks—in the case of PLA, reducing it to lactic acid, which can feed the soil microbes in compost. The polymer wrapping also degrades.

The process eliminates microplastics, a byproduct of many chemical degradation processes and a pollutant in its own right.

Near-complete depolymerization of polyesters with nano-dispersed enzymes, Nature (2021). DOI: 10.1038/s41586-021-03408-3

https://phys.org/news/2021-04-biodegradable-plastics-compostable.ht...

Comment by Dr. Krishna Kumari Challa on April 21, 2021 at 10:41am

Should Facebook and Twitter review your posts before they're published?

The day is coming when your posts to social media may travel through checkpoints before the messages go public.

All of your posts to Facebook, Twitter, and other social platforms may be instantly examined by an artificial intelligence filter that roots out hate speech and misinformation. Some posts that have been flagged by artificial intelligence may then be reviewed by a human supervisor.

social media filters are needed because the platforms have grown and scaled faster than they can be regulated—with the result that social channels are now being accused of enabling hate speech and misinformation that contributes to violence.

comprehensive regulations will include heavy government fines for platforms that enable hate speech and misinformation. Such penalties will create additional incentives to invest in the necessary content moderation and technology.

https://techxplore.com/news/2021-04-facebook-twitter-theyre-publish...

Comment by Dr. Krishna Kumari Challa on April 21, 2021 at 10:31am

Orbital debris threatens satellites: Time to act

Comment by Dr. Krishna Kumari Challa on April 21, 2021 at 10:22am

Omega-3 supplements do double duty in protecting against stress

A high daily dose of an omega-3 supplement may help slow the effects of aging by suppressing damage and boosting protection at the cellular level during and after a stressful event, new research suggests.

Researchers found that daily supplements that contained 2.5 grams of omega-3 polyunsaturated fatty acids, the highest dose tested, were the best at helping the body resist the damaging effects of stress.

Compared to the placebo group, participants taking omega-3 supplements produced less of the stress hormone cortisol and lower levels of a pro-inflammatory protein during a stressful event in the lab. And while levels of protective compounds sharply declined in the placebo group after the stressor, there were no such decreases detected in people taking omega-3s.

The supplements contributed to what the researchers call stress resilience: reduction of harm during stress and, after acute stress, sustained anti-inflammatory activity and protection of cell components that shrink as a consequence of aging.

Annelise A. Madison et al. Omega-3 supplementation and stress reactivity of cellular aging biomarkers: an ancillary substudy of a randomized, controlled trial in midlife adults, Molecular Psychiatry (2021). DOI: 10.1038/s41380-021-01077-2

https://medicalxpress.com/news/2021-04-omega-supplements-duty-stres...

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Comment by Dr. Krishna Kumari Challa on April 21, 2021 at 10:18am

Flushing a public toilet? Don't linger, because aerosolized droplets do

Flushing a toilet can generate large quantities of microbe-containing aerosols depending on the design, water pressure or flushing power of the toilet. A variety of pathogens are usually found in stagnant water as well as in urine, feces and vomit. When dispersed widely through aerosolization, these pathogens can cause Ebola, norovirus that results in violent food poisoning, as well as COVID-19 caused by SARS-CoV-2.

Respiratory droplets are the most prominent source of transmission for COVID-19, however, alternative routes may exist given the discovery of small numbers of viable viruses in urine and stool samples. Public restrooms are especially cause for concern for transmitting COVID-19 because they are relatively confined, experience heavy foot traffic and may not have adequate ventilation.

A team of scientists put physics of fluids to the test to investigate droplets generated from flushing a toilet and a urinal in a public rest room under normal ventilation conditions. To measure the droplets, they used a particle counter placed at various heights of the toilet and urinal to capture the size and number of droplets generated upon flushing.

Results of the study, published in the journal Physics of Fluids, demonstrate how public restrooms could serve as hotbeds for airborne disease transmission, especially if they do not have adequate ventilation or if toilets do not have a lid or cover. 

The droplets were detected at heights of up to 5 feet for 20 seconds or longer after initiating the flush. Researchers detected a smaller number of droplets in the air when the toilet was flushed with a closed lid, although not by much, suggesting that aerosolized droplets escaped through small gaps between the cover and the seat.

Jesse H. Schreck et al, Aerosol generation in public restrooms, Physics of Fluids (2021). DOI: 10.1063/5.0040310

Using a public restroom? Mask up!

https://phys.org/news/2021-04-flushing-toilet-dont-linger-aerosoliz...

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Comment by Dr. Krishna Kumari Challa on April 20, 2021 at 10:10am

Russian scientists discover a new gene regulation mechanism

A team of scientists from Russia studied the role of double-stranded fragments of the maturing RNA and showed that the interaction between distant parts of the RNA can regulate gene expression. The research was published in Nature Communications.

At school, we learn that DNA is double-stranded and RNA is single-stranded, but that is not entirely true. Scientists have encountered many cases of RNA forming a double-stranded (a.k.a. secondary) structure that plays an important role in the functioning of RNA molecules. These structures are involved in the regulation of gene expression, where the double-stranded regions typically carry specific functions and, if lost, may cause severe disorders. A double-stranded structure is created by sticky complementary regions. For the strands to stick to each other, U and G should appear opposite A and C, respectively. The majority of the sticking regions are located close to one another, but the role of those located far apart has not been well understood.

Scientists from the Skoltech Center for Life Sciences (CLS) led by professor Dmitri Pervouchine and their colleagues from Russian and international laboratories used molecular and bioinformatics techniques to analyze the structure and roles of complementary RNA regions spaced far apart but capable of forming secondary structures. It transpired that the secondary structure plays an important role in the maturation of information-carrying RNA molecules and particularly in splicing, a process in which non-coding regions are cut out, and the coding regions are stitched together. The team showed that the RNA secondary structures can regulate splicing and thus contribute strongly to gene regulation.

"This paper culminates years of research on the RNA secondary structure and its role in the regulation of gene expression. We have published an extensive computation-based catalog of potentially important RNA structures, but the experimental research in this direction is just starting", professor Pervouchine comments.

Web: https://www.skoltech.ru/en.

https://www.eurekalert.org/pub_releases/2021-04/sios-rsd041921.php

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Comment by Dr. Krishna Kumari Challa on April 20, 2021 at 9:47am

Study finds humans are directly influencing wind and weather over N...

A new study led by scientists at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science provides evidence that humans are influencing wind and weather patterns across the eastern United States and western Europe by releasing CO2 and other pollutants into Earth's atmosphere.

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Ocean currents modulate oxygen content at the equator

Due to global warming, not only the temperatures in the atmosphere and in the ocean are rising, but also winds and ocean currents as well as the oxygen distribution in the ocean are changing. For example, the oxygen content in the ocean has decreased globally by about 2% in the last 60 years, particularly strong in the tropical oceans. However, these regions are characterized by a complex system of ocean currents. At the equator, one of the strongest currents, the Equatorial Undercurrent (EUC), transports water masses eastwards across the Atlantic. The water transport by the EUC is more than 60 times larger than that of the Amazon river.

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When stars get too close to each other, they cast out interstellar ...

In October 2017, humanity caught its first-ever glimpse of an interstellar object—a visitor from beyond our solar system—passing nearby the sun. We named it "Oumuamua, and its unusual properties fascinated and confounded astronomers. Less than two years later, amateur astronomer Gennady Borisov found a second interstellar object: a comet-like body that began to disintegrate as it passed within 2 AU of the sun (1 AU equals the distance from Earth to the sun). Where do these interstellar objects come from? How common are they? With a sample size of just two, it's difficult to make any generalizations just yet. On the other hand, given what we know about star formation, we can begin to make some inferences about the likely origins of these objects, and what we are likely to see of them in the future.

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