Comment

Comment by Dr. Krishna Kumari Challa on July 7, 2020 at 8:01am

Coconut oil production may be more damaging to the environment than palm oil, researchers say.

According to the study, production of coconut oil affects 20 threatened species (including plants and animals) per million tons of oil produced. This is higher than other oil-producing crops, such as palm (3.8 species per million tons), olive (4.1) and soybean (1.3).

The study shows that the main reason for the high number of species affected by coconut is that the crop is mostly grown on tropical islands with rich diversity and many unique species.

Impact on threatened species is usually measured by the number of species affected per square hectare of land used—and by this measure palm's impact is worse than coconut.

Coconut cultivation is thought to have contributed to the extinction of a number of island species, including the Marianne white-eye in the Seychelles and the Solomon Islands' Ontong Java flying fox.

Species not yet extinct but threatened by coconut production include the Balabac mouse-deer, which lives on three Philippine islands, and the Sangihe tarsier, a primate living on the Indonesian island of Sangihe.

Consumers need to realize that all our agricultural commodities, and not just tropical crops, have negative environmental impacts.

 Source: Erik Meijaard et al, Coconut oil, conservation and the conscientious consumer, Current Biology (2020). DOI: 10.1016/j.cub.2020.05.059

https://phys.org/news/2020-07-coconut-reveals-consumer-conundrum.ht...

Comment by Dr. Krishna Kumari Challa on July 7, 2020 at 7:47am

Expalined:the dead-water phenomenon

What makes ships mysteriously slow down or even stop as they travel, even though their engines are working properly? This was first observed in 1893 and was described experimentally in 1904 without all the secrets of this 'dead water' being understood. An interdisciplinary team from the CNRS and the University of Poitiers has explained this phenomenon for the first time: the speed changes in ships trapped in dead water are due to waves that act like an undulating conveyor belt on which the boats move back and forth. This work was published in PNAS on July 6, 2020.

In earlier times ships wwere slowed by a mysterious force and he could barely maneuver, let alone pick up normal speed. In 1904, the Swedish physicist and oceanographer Vagn Walfrid Ekman showed in a laboratory that waves formed under the surface at the interface between the salt water and freshwater layers that form the upper portion of this area of the Arctic Ocean interact with the ship, generating drag.

This phenomenon, called dead water, is seen in all seas and oceans where waters of different densities (because of salinity or temperature) mix. It denotes two drag phenomena observed by scientists. The first, Nansen wave-making drag, causes a constant, abnormally low speed. The second, Ekman wave-making drag, is characterized by speed oscillations in the trapped boat. The cause of this was unknown. Physicists, fluid mechanics experts, and mathematicians at the CNRS' Institut Prime and the Laboratoire de Mathématiques et Applications (CNRS/Université de Poitiers) have attempted to solve this mystery. They used a mathematical classification of different internal waves and analysis of experimental images at the sub-pixel scale, a first.

This work showed that these speed variations are due to the generation of specific waves that act as an undulating conveyor belt on which the ship moves back and forth. The scientists have also reconciled the observations of both Nansen and Ekman. They have shown that the Ekman oscillating regime is only temporary: the ship ends up escaping and reaches the constant Nansen speed.

Source: Johan Fourdrinoy el al., "The dual nature of the dead-water phenomenology: Nansen versus Ekman wave-making drags," PNAS (2020). www.pnas.org/cgi/doi/10.1073/pnas.1922584117

https://phys.org/news/2020-07-dead-water-phenomenon.html?utm_source...

Comment by Dr. Krishna Kumari Challa on July 7, 2020 at 7:10am

How to protect people from radiation exposure.

A safe and powerful treatment for the body against deadly radiation

Researchers have reported a highly effective and safe nanocrystal to combat dangerous doses of radiation. By growing manganese oxide (Mn₃O₄) nanocrystals on top of Cerium oxide (CeO₂) nanocrystals, the research team boosted the catalytic activity of the CeO₂/Mn₃O₄ nanocrystals in their ability to stave off side effects of deadly radiation.

Excessive reactive oxygen species (ROS) are found in a number of major diseases including sepsis, cancer, cardiovascular disease, and Parkinson's disease, just to name a few. A powerful antioxidant that can work at low doses only can ensure sustainable applications of radiation in medical, industrial and military settings and more. These new CeO₂/Mn₃O₄ hetero-structured nanocrystals are five times stronger than when CeO₂ or Mn₃O₄ does the job alone.

When our body is exposed to high levels of radiation, a massive amount of ROS are generated within milliseconds due to the decomposition of water molecules. These ROS severely damage cells, eventually leading to their death. The research team looked to CeO₂ and Mn₃O₄ nanoparticles for their outstanding ROS scavenging abilities. The challenge was how to apply these antioxidant nanomaterials in a safe and economic way. Though effective, CeO₂ and Mn₃O₄ nanoparticles can remove ROS only in high doses. They are also rare materials and difficult to obtain.

The researchers drew on the approach usually taken in the field of catalysis: stacking nanoparticles with different lattice parameters results in surface strain and increases oxygen vacancies on the surface of the nanocrystal. "The synergistic effect of the strain generated on Mn₃O₄ and the increased oxygen vacancy on the CeO₂ surface improved the surface binding affinity of the ROS, boosting the catalytic activity of the nanocrystals.

These CeO₂/Mn₃O₄ nanocrystals prove their powerful antioxidant effects to protect our whole body effectively just in small doses.

Sang Ihn Han et al, Epitaxially Strained CeO₂ /Mn₃ O₄ Nanocrystals as an Enhanced Antioxidant for Radioprotection, Advanced Materials (2020). DOI: 10.1002/adma.202001566

https://phys.org/news/2020-07-safe-powerful-treatment-body-deadly.h...

Comment by Dr. Krishna Kumari Challa on July 7, 2020 at 6:35am

WOW: a stunningly lifelike fleet of robo-birds that glide through the air with guidance from an ultra-sideband radio system.

Each of the five swallows weighs 42 grams. They each are powered by three tiny motors for direction, lift and descent. Their wingspan extends to 26 inches.

Artificial lamellae and quill are designed to replicate realistic motion. When the BionicSwift models rise, the lamellae bunch up to help provide lift. When they descend, they fan out to allow air to pass through. They can glide gracefully, make sharp turns and fly in loops.

The intelligent interaction of motors and mechanics allows the frequency of the wing beat and the elevator's angle of attack to be precisely adjusted for the various maneuvers," according to a report on the BionicSwift on Festo's web site.

The birds carry a 6 gram battery and they are guided by GPS sensors located throughout the enclosed flying area. The birds follow a preprogrammed flight  path, but if an unexpected factor arises, such as a gust of air, radio communication enables instantaneous flight rerouting.

https://techxplore.com/news/2020-07-german-firm-bionic-birds.html?u...

Comment by Dr. Krishna Kumari Challa on July 7, 2020 at 6:19am

Dying stars breathe life into Earth: study

As dying stars take their final few breaths of life, they gently sprinkle their ashes into the cosmos through the magnificent planetary nebulae. These ashes, spread via stellar winds, are enriched with many different chemical elements, including carbon.

Findings from a study published today in Nature Astronomy show that the final breaths of these dying stars, called white dwarfs, shed light on carbon's origin in the Milky Way.

"The findings pose new, stringent constraints on how and when carbon was produced by stars of our galaxy, ending up within the raw material from which the Sun and its planetary system were formed 4.6 billion years ago.

The origin of carbon, an element essential to life on Earth, in the Milky Way galaxy is still debated among astrophysicists: some are in favor of low-mass stars that blew off their carbon-rich envelopes by stellar winds became white dwarfs, and others place the major site of carbon's synthesis in the winds of massive stars that eventually exploded as supernovae.

Using data from the Keck Observatory near the summit of Mauna Kea volcano in Hawaii collected between August and September 2018, the researchers analyzed white dwarfs belonging to the Milky Way's open star clusters. Open star clusters are groups of up to a few thousand stars held together by mutual gravitational attraction.

From this analysis, the research team measured the white dwarfs' masses, and using the theory of stellar evolution, also calculated their masses at birth.

The connection between the birth masses to the final white dwarf masses is called the initial-final mass relation, a fundamental diagnostic in astrophysics that contains the entire life cycles of stars. Previous research always found an increasing linear relationship: the more massive the star at birth, the more massive the white dwarf left at its death.

But when Cummings and his colleagues calculated the initial-final mass relation, they were shocked to find that the white dwarfs from this group of open clusters had larger masses than astrophysicists previously believed. This discovery, they realized, broke the linear trend other studies always found. In other words, stars born roughly 1 billion years ago in the Milky Way didn't produce white dwarfs of about 0.60-0.65 solar masses, as it was commonly thought, but they died leaving behind more massive remnants of about 0.7—0.75 solar masses.

The researchers say that this kink in the trend explains how carbon from low-mass stars made its way into the Milky Way. In the last phases of their lives, stars twice as massive as the Milky Way's Sun produced new carbon atoms in their hot interiors, transported them to the surface and finally spread them into the surrounding interstellar environment through gentle stellar winds.

Carbon star formation as seen through the non-monotonic initial–final mass relation, Nature Astronomy (2020). DOI: 10.1038/s41550-020-1132-1 , www.nature.com/articles/s41550-020-1132-1

https://phys.org/news/2020-07-dying-stars-life-earth.html?utm_sourc...

Comment by Dr. Krishna Kumari Challa on July 7, 2020 at 6:11am

Group genomics drive aggression in honey bees

Researchers often study the genomes of individual organisms to try to tease out the relationship between genes and behavior. A new study of Africanized honey bees reveals, however, that the genetic inheritance of individual bees has little influence on their propensity for aggression. Instead, the genomic traits of the hive as a whole are strongly associated with how fiercely its soldiers attack.

https://phys.org/news/2020-07-group-genomics-aggression-honey-bees....

--

https://phys.org/news/2020-07-simulations-magnetic-field-faster-pre...

Simulations show magnetic field can change 10 times faster than previously thought

--

https://phys.org/news/2020-07-reveals-secret-life-lithium-sun-like....

Study reveals secret life of lithium in Sun-like stars

--

https://phys.org/news/2020-07-parasite.html?utm_source=nwletter&...

Parasite research heats up

--

https://phys.org/news/2020-07-bacteria-natural-products.html?utm_so...

How do bacteria build up natural products

Comment by Dr. Krishna Kumari Challa on July 6, 2020 at 9:49am

https://theconversation.com/how-the-brain-builds-a-sense-of-self-fr...

How the brain builds a sense of self from the people around us – new research

Hundreds of elephants are mysteriously dying in Botswana – a conservationist explains what we know

https://theconversation.com/hundreds-of-elephants-are-mysteriously-...

--

https://phys.org/news/2020-07-tiny-ancient-relative-dinosaurs-ptero...

A tiny ancient relative of dinosaurs and pterosaurs discovered

Dinosaurs and flying pterosaurs may be known for their remarkable size, but a newly described species from Madagascar that lived around 237 million years ago suggests that they originated from extremely small ancestors. The fossil reptile, named Kongonaphon kely, or "tiny bug slayer," would have stood just 10 centimeters (or about 4 inches) tall.

--

https://phys.org/news/2020-07-atomic-swiss-army-knife-precisely.htm...

Atomic 'Swiss Army knife' precisely measures materials for quantum computers

--

https://phys.org/news/2020-07-approach-yet-unconfirmed-rare-nuclear...

Researchers develop novel approach to modeling yet-unconfirmed rare nuclear process

Researchers develop novel approach to modeling yet-unconfirmed rare nuclear process: a theoretical first-principles description of neutrinoless double-beta decay.

Comment by Dr. Krishna Kumari Challa on July 6, 2020 at 8:31am

Declining eyesight improved by looking at deep red light

Declining eyesight can be improved by looking at deep red light: Staring at a deep red light for three minutes a day can significantly improve declining eyesight, finds a new study, the first of its kind in humans. This finding could signal the dawn of new affordable home-based eye therapies, helping the millions of people globally with naturally declining vision.

As you age your visual system declines significantly, particularly once over 40.

Your retinal sensitivity and your colour vision are both gradually undermined, and with an aging population, this is an increasingly important issue. To try to stem or reverse this decline, we sought to reboot the retina's aging cells with short bursts of longwave light.

In humans around 40 years-old, cells in the eye's retina begin to age, and the pace of this aging is caused, in part, when the cell's mitochondria, whose role is to produce energy (known as ATP) and boost cell function, also start to decline.

Mitochondrial density is greatest in the retina's photoreceptor cells, which have high energy demands. As a result, the retina ages faster than other organs, with a 70% ATP reduction over life, causing a significant decline in photoreceptor function as they lack the energy to perform their normal role.

Researchers built on their previous findings in mice, bumblebees and fruit flies, which all found significant improvements in the function of the retina's photoreceptors when their eyes were exposed to 670 nanometre (long wavelength) deep red light.

Mitochondria have specific light absorbance characteristics influencing their performance: longer wavelengths spanning 650 to 1000nm are absorbed and improve mitochondrial performance to increase energy production.

Researchers found the 670nm light had no impact in younger individuals, but in those around 40 years and over, significant improvements were obtained.

Cone color contrast sensitivity (the ability to detect colors) improved by up to 20% in some people aged around 40 and over. Improvements were more significant in the blue part of the color spectrum that is more vulnerable in aging.

Rod sensitivity (the ability to see in low light) also improved significantly in those aged around 40 and over, though less than color contrast.

Source: Harpreet Shinhmar et al, Optically improved mitochondrial function redeems aged human visual decline, The Journals of Gerontology: Series A (2020). DOI: 10.1093/gerona/glaa155

https://medicalxpress.com/news/2020-06-declining-eyesight-deep-red....

Comment by Dr. Krishna Kumari Challa on July 6, 2020 at 6:34am

Explaining science: Stellar Aberration

https://explainingscience.org/2019/05/28/stellar-aberration/

--

https://theconversation.com/the-us-has-bought-most-of-the-worlds-re...

The US has bought most of the world’s remdesivir. Here’s what it means for the rest of the world

--

**WHO underplaying risk of airborne spread of Covid-19, say scientists

Open letter says there is emerging evidence of potential for aerosol transmission

https://www.theguardian.com/world/2020/jul/05/who-underplaying-risk...

--

https://www.sciencenews.org/article/caecilians-amphibians-venomous-...

Bizarre caecilians may be the only amphibians with venomous bites

Creatures that look like snakes appear to have glands near their teeth that secrete venom

Comment by Dr. Krishna Kumari Challa on July 5, 2020 at 12:26pm

Dopamine:

• ‹ Previous
• 1
• …
• 797
• 798
• 799
• 800
• 801
• …
• 1079
• Next ›
• Page