Comment

Comment by Dr. Krishna Kumari Challa on September 12, 2020 at 6:48am

Computational modelling explains why blues and greens are brightest colous in nature

Researchers have shown why intense, pure red colors in nature are mainly produced by pigments, instead of the structural color that produces bright blue and green hues.

The researchers, from the University of Cambridge, used a numerical experiment to determine the limits of matt structural color—a phenomenon which is responsible for some of the most intense colors in nature—and found that it extends only as far as blue and green in the visible spectrum. The results, published in PNAS, could be useful in the development of non-toxic paints or coatings with intense color that never fades.

Structural color, which is seen in some bird feathers, butterfly wings or insects, is not caused by pigments or dyes, but internal structure alone. The appearance of the color, whether matt or iridescent, will depending on how the structures are arranged at the nanoscale.

Ordered, or crystalline, structures result in iridescent colors, which change when viewed from different angles. Disordered, or correlated, structures result in angle-independent matt colors, which look the same from any viewing angle. Since structural color does not fade, these angle-independent matt colors would be highly useful for applications such as paints or coatings, where metallic effects are not wanted.

In addition to their intensity and resistance to fading, a matt paint which uses structural color would also be far more environmentally-friendly, as toxic dyes and pigments would not be needed.

Gianni Jacucci et al, The limitations of extending nature's color palette in correlated, disordered systems, Proceedings of the National Academy of Sciences (2020). DOI: 10.1073/pnas.2010486117

https://phys.org/news/2020-09-blues-greens-brightest-colous-nature....

Comment by Dr. Krishna Kumari Challa on September 12, 2020 at 6:12am

https://www.livescience.com/65117-do-elephant-tusks-or-rhino-horns-....

Do Elephant Tusks or Rhino Horns Ever Grow Back?

Elephant tusks do not grow back, but rhino horns do.

--

scientists have developed a non-invasive technique for unraveling the complex dynamics generated by spinal cord circuits to unprecedented detail, a first in functional magnetic resonance imaging that may one day help diagnose spinal cord dysfunction or injury. 

--

 

Children born to mothers who had diabetes during pregnancy may age faster biologically and be at an increased risk for obesity and high blood pressure

https://researchnews.cc/news/2454/Gestational-diabetes-may-accelera...

Comment by Dr. Krishna Kumari Challa on September 12, 2020 at 5:49am

Researchers quantify worldwide loss of phosphorus due to soil erosion for the first time

Phosphorus is essential for agriculture, yet this important plant nutrient is increasingly being lost from soils around the world. The primary cause is soil erosion, reports an international research team.

The world's food production depends directly on phosphorus. However, this plant nutrient is not unlimited, originating from finite geological reserves.

Erosion flushes mineral-bound phosphorus out of agricultural soils into wetlands and water bodies, where the excess of nutrients (called eutrophication) harms the aquatic plant and animal communities. The researchers were able to validate their calculations using globally published measurement data on phosphorus content in rivers: The elevated phosphorus content in waters mirrors the calculated loss of phosphorus in the soil in the respective region.

Mineral fertilizers can replace the lost phosphorus in the fields, but not all countries are equally able to use them.

 Christine Alewell et al. Global phosphorus shortage will be aggravated by soil erosion, Nature Communications (2020). DOI: 10.1038/s41467-020-18326-7

https://phys.org/news/2020-09-quantify-worldwide-loss-phosphorus-du...

Comment by Dr. Krishna Kumari Challa on September 12, 2020 at 5:40am

Infection higher in hospital cleaners than ICU staff: report

Intensive care medics were significantly less likely to have been infected with COVID-19 than cleaners and other healthcare workers in departments deemed lower risk, according to a study of several British hospitals at the peak of the pandemic.

The research also found that people of black, Asian and minority ethnicity were nearly twice as likely to have been infected as white colleagues.

It follows several studies suggesting race, income and allocation of personal protective equipment (PPE) create biases in the burden of infections.

Researchers said the results could be because those working in intensive therapy units (ITU) were prioritised for the highest level of masks and other equipment.

SARS-CoV-2 seroprevalence and asymptomatic viral carriage in healthcare workers: a cross-sectional study, Thorax (2020). DOI: 10.1136/thoraxjnl-2020-215414

https://medicalxpress.com/news/2020-09-infection-higher-hospital-cl...

Comment by Dr. Krishna Kumari Challa on September 11, 2020 at 9:00am

Terroir: can a crop’s environment shape a food’s smell and taste? Scientists explore whether terroir leaves a lasting imprint

https://www.sciencenews.org/article/terroir-food-crops-environment-...

--

More than 90% of protected areas are disconnected

https://phys.org/news/2020-09-areas-disconnected.html?utm_source=nw...

--

To repair a damaged heart, three cells are better than one

https://medicalxpress.com/news/2020-09-heart-cells.html?utm_source=...

Comment by Dr. Krishna Kumari Challa on September 11, 2020 at 6:24am

"Using noise to fight noise": 

Sick of city din? Try 'noise-cancelling headphones' for your flat

https://techxplore.com/news/2020-09-sick-city-din-noise-cancelling-...

--

5 ways our immune responses to COVID vaccines are unique

https://theconversation.com/5-ways-our-immune-responses-to-covid-va...

--

Carbon-rich exoplanets may be made of diamonds

When stars and planets are formed, they do so from the same cloud of gas, so their bulk compositions are similar. A star with a lower carbon to oxygen ratio will have planets like Earth, comprised of silicates and oxides with a very small diamond content (Earth's diamond content is about 0.001%).

But exoplanets around stars with a higher carbon to oxygen ratio than our sun are more likely to be carbon-rich.Researchers hypothesized that these carbon-rich exoplanets could convert to diamond and silicate, if water (which is abundant in the universe) were present, creating a diamond-rich composition.

H. Allen-Sutter et al, Oxidation of the Interiors of Carbide Exoplanets, The Planetary Science Journal (2020). DOI: 10.3847/PSJ/abaa3e

https://phys.org/news/2020-09-carbon-rich-exoplanets-diamonds.html?...

--

Comment by Dr. Krishna Kumari Challa on September 11, 2020 at 6:22am

The Astounding Fact About The Universe - Neil Degrasse Tyson

--
How do vaccines work?

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

Big 'particle accelerator' in the sky!

The Earth's magnetic field traps high-energy particles. When the first satellites were launched into space, scientists led by James Van Allen unexpectedly discovered the high-energy particle radiation regions, which were later named after its discoverer: the Van Allen Radiation Belts. Visualized, these look like two donut-shaped regions encompassing the planet.

Now, a new study led by researchers from GFZ German Research Center for Geosciences shows that electrons in the radiation belts can be accelerated to very high speeds locally. The study shows that magnetosphere works as a very efficient particle accelerator, speeding up electrons to so-called ultra-relativistic energies.

To better understand the origin of the Van Allen Belts, in 2012, NASA launched the Van Allen Probes twin spacecraft to traverse this most harsh environment and conduct detailed measurements in this hazardous region. The measurements included a full range of particles moving at different speeds and in different directions, and plasma waves. Plasma waves are similar to the waves that we see on the water surface, but are invisible to the naked eye. They can be compared to ripples in the electric and magnetic field.

Recent observations revealed that the energy of electrons in the belts can go up to so called ultra-relativistic energies. These electrons, with temperatures above 100 billion degrees Fahrenheit, move so quickly that their energy of motion is much higher than their energy of rest given by Einstein's famous formula E=mc². They are so fast that the time significantly slows down for these particles.

Scientists were surprised to find these ultra-relativistic electrons and assumed that such high energies can be only reached by a combination of two processes: the inward transport of particles from the outer regions of the magnetosphere, which accelerates them, and a local acceleration of particles by plasma waves.

However, the new study shows that electrons reach such incredible energies locally, in the heart of the belts, by taking all this energy from plasma waves. This process turns out to be extremely efficient. The unexpected discovery of how acceleration of particles to ultra-relativistic energies operates in the near-Earth space may help scientists understand the fundamental processes of acceleration on the sun, near outer planets, and even in the distant corners of the universe, where space probes cannot reach.

Hayley Allison, Yuri Shprits: "Local heating of radiation belt electrons to ultra-relativistic energies" Nature Communications, DOI: 10.1038/s41467-020-18053-z

https://phys.org/news/2020-09-giant-particle-sky.html?utm_source=nw...

Comment by Dr. Krishna Kumari Challa on September 11, 2020 at 6:05am

Study finds humans are behind costly, increasing risk of wildfire to millions of homes

People are starting almost all the wildfires that threaten U.S. homes, according to an innovative new analysis combining housing and wildfire data. Through activities like debris burning, equipment use and arson, humans were responsible for igniting 97% of home-threatening wildfires, a University of Colorado Boulder-led team reported this week in the journal Fire.

Nathan Mietkiewicz et al, In the Line of Fire: Consequences of Human-Ignited Wildfires to Homes in the U.S. (1992–2015), Fire (2020). DOI: 10.3390/fire3030050

https://phys.org/news/2020-09-humans-costly-wildfire-millions-homes...

Comment by Dr. Krishna Kumari Challa on September 11, 2020 at 5:47am

At least 28 extinctions prevented by conservation action in recent decades

Conservation action has prevented the global extinction of at least 28 bird and mammal species since 1993, a study  has shown.

The species include Puerto Rican Amazon Amazona vittata, Przewalski's Horse Equus ferus, Alagoas Antwren Myrmotherula snowi, Iberian Lynx Lynx pardinus, and Black Stilt Himantopus novaezelandiae, among others.

an international team of scientists have estimated the number of bird and mammal species that would have disappeared forever without the efforts of conservationists in recent decades.

The researchers found that 21-32 bird and 7-16 mammal species extinctions have been prevented since 1993, with the ranges reflecting the uncertainty inherent in estimating what might have happened under hypothetical circumstances.

Bolam, F.C, Mair, L., Angelico, M., Brooks, T.M, Burgman, M., McGowan, P. J. K & Hermes, C. et al. (2020). How many bird and mammal extinctions has recent conservation action prevented? Conservation Letters (2020). DOI: 10.1111/conl.12762

https://phys.org/news/2020-09-extinctions-action-decades.html?utm_s...

• ‹ Previous
• 1
• …
• 725
• 726
• 727
• 728
• 729
• …
• 1042
• Next ›
• Page