19 Nov

Posted at 15:33h in Scoop.it

Black holes ‘have no hair’: no attributes that can be used to tell them apart. Extreme black holes (spinning at maximally allowed rate) can have an additional property, permanent hair that is made of a massless scalar field. Nearly extreme black holes (like Gargantua, the black hole featured in the movie "Interstellar") have hair that is a transient phenomenon: nearly extreme black holes that attempt to regrow hair will lose it and become bald again.

 

The black holes of Einstein’s theory of relativity can be completely described by just three parameters: their mass, spin angular momentum, and electric charge. Since two black holes that share these parameters cannot be distinguished, regardless of how they were made, black holes are said to "have no hair"—they have no additional attributes that can be used to tell them apart.

 

 

Sourced through Scoop.it from: phys.org

11 Nov

Posted at 11:35h in Scoop.it

Researchers, inspired by diving bell spiders and rafts of fire ants, have created a metallic structure that is so water repellent, it refuses to sink—no matter how often it is forced into water or how much it is damaged or punctured.

 

Could this lead to an unsinkable ship? A wearable flotation device that will still float after being punctured? Electronic monitoring devices that can survive in long term in the ocean? All of the above, says Chunlei Guo, professor of optics and physics, whose lab describes the structure in ACS Applied Materials and Interfaces

 

.The structure uses a groundbreaking technique the lab developed for using femtosecond bursts of lasers to “etch” the surfaces of metals with intricate micro- and nanoscale patterns that trap air and make the surfaces superhydrophobic, or water repellent.

Sourced through Scoop.it from: www.rochester.edu

11 Nov

Posted at 11:34h in Scoop.it

2019 is the International Year of the Periodic Table of Elements. Here, we discuss the history of the periodic table as well as the designated year.

 

Elements 113, 115, 117 and 118 — fill out the seventh row of the periodic table of the elements. All are superheavies. That’s why they sit at the base right of the bench (see above). Naming rights classically go to those who find an element. And that’s what happen here. Element 113 was found by scientists at RIKEN in Wako, Japan. They have requested to call it Nihonium, to be shortened as Nh. This name comes from Nihon. It’s Japanese for “Land of the Rising Sun,” which is what a lot of people call Japan. Element 115 will turn out to be Moscovium, abridged as Mc. It refers to the Moscow area. And that was where the combined organization for Nuclear Research is based (Dubna). It exposed number 115 in a teamwork with researchers at Lawrence Livermore National Laboratory in California and Oak Ridge National Laboratory (ORNL) in Tennessee. That’s why Tennessee also gets a periodic table entry. It’s the home location of ORNL, Vanderbilt University & the University of Tennessee. So element 117 will become Tennessine and will be represented by the symbol Ts.

Sourced through Scoop.it from: www.comsol.com

07 Nov

Posted at 19:01h in Scoop.it

A clever new study shows that blue whales lean on their memory to guide their epic migrations.

 

The blue whales of the North Pacific spend their winters in their breeding grounds off California and Costa Rica. Come spring, they swim up the coast of North America toward the food-rich summer waters of the Pacific Northwest. They could make the journey in two months (and they do, on the reverse trip back south). Instead, they take twice that time, pausing to gorge themselves on blooms of krill that appear along the way. It’s a leisurely season-long tour of a continent-wide buffet line.

 

Sourced through Scoop.it from: www.theatlantic.com

07 Nov

Posted at 18:53h in Scoop.it

New technique makes it easier to build stable “tissues”

 

3D-printed tissues and organs could revolutionize transplants, drug screens, and lab models—but replicating complicated body parts such as gastric tracts, windpipes, and blood vessels is a major challenge. That’s because these vascularized tissues are hard to build up in traditional solid layer-by-layer 3D printing without constructing supporting scaffolding that can later prove impossible to remove.

 

One potential solution is replacing these support structures with liquid—a specially designed fluid matrix into which liquid designs could be injected before the “ink” is set and the matrix is drained away. But past attempts to make such aqueous structures have literally collapsed, as their surfaces shrink and their structures crumple into useless blobs.

 

Sourced through Scoop.it from: www.sciencemag.org

07 Nov

Posted at 18:51h in Scoop.it

Birds display a rainbow palette of colors, many of which come from special arrangements of melanin, the pigment that gives color to our skin. Researchers at the University of Akron have developed a safe and stable pigment based on the melanin structures.

 

In the colorful world in which we live, colors are significant for not only aesthetics and pleasure, but also for communication, signaling, and security. Colors are produced through either absorption of light by molecules — pigmentary colors — or scattering of light by nanostructures — structural colors.

 

 

Sourced through Scoop.it from: wksu.org

26 Oct

Posted at 14:03h in Scoop.it

"

  • Anxiety about the effects of social media on young people has risen to such an extreme that giving children smartphones is sometimes equated to handing them a gram of cocaine. The reality is much less alarming.

 

  • A close look at social media use shows that most young texters and Instagrammers are fine. Heavy use can lead to problems, but many early studies and news headlines have overstated dangers and omitted context.

 

  • Researchers are now examining these diverging viewpoints, looking for nuance and developing better methods for measuring whether social media and related technologies have any meaningful impact on mental health."

Sourced through Scoop.it from: www.scientificamerican.com