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Comment by Dr. Krishna Kumari Challa on February 11, 2021 at 8:59am

Scientists create liquid crystals that look a lot like their solid counterparts

A research team  has designed new kinds of liquid crystals that mirror the complex structures of some solid crystals—a major step forward in building flowing materials that can match the colorful diversity of forms seen in minerals and gems, from lazulite to topaz.

The group's findings, published today in the journal Nature, may one day lead to new types of smart windows and television or computer displays that can bend and control light like never before.

The results come down to a property of solid crystals that will be familiar to many chemists and gemologists: Symmetry

DOI: 10.1038/s41586-021-03249-0 Wensink, H.H. et al. Thermally reconfigurable monoclinic nematic colloidal fluids. Nature 590, 268–274 (2021). doi.org/10.1038/s41586-021-03249-0

https://phys.org/news/2021-02-scientists-liquid-crystals-lot-solid....

Comment by Dr. Krishna Kumari Challa on February 11, 2021 at 8:55am

Imaging Habitable-Zone Exoplanets

Comment by Dr. Krishna Kumari Challa on February 11, 2021 at 8:50am

A new way to look for life-sustaining planets

It is now possible to capture images of planets that could potentially sustain life around nearby stars, thanks to advances reported by an international team of astronomers in the journal Nature Communications.

Using a newly developed system for mid-infrared exoplanet imaging, in combination with a very long observation time, the study's authors say they can now use ground-based telescopes to directly capture images of planets about three times the size of Earth within the habitable zones of nearby stars.

Efforts to directly image exoplanets—planets outside our solar system—have been hamstrung by technological limitations, resulting in a bias toward the detection of easier-to-see planets that are much larger than Jupiter and are located around very young stars and far outside the habitable zone—the "sweet spot" in which a planet can sustain liquid water. If astronomers want to find alien life, they need to look elsewhere.

"If we want to find planets with conditions suitable for life as we know it, we have to look for rocky planets roughly the size of Earth, inside the habitable zones around older, sun-like stars.

The method described in the paper provides more than a tenfold improvement over existing capabilities to directly observe exoplanets. Most studies on exoplanet imaging have looked in infrared wavelenghts of less than 10 microns, stopping just short of the range of wavelengths where such planets shine the brightest. There is a good reason for that because the Earth itself is shining at you at those wavelengths. Infrared emissions from the sky, the camera and the telescope itself are essentially drowning out your signal. But the good reason to focus on these wavelengths is that's where an Earthlike planet in the habitable zone around a sun-like star is going to shine brightest.

 Imaging low-mass planets within the habitable zone of Alpha; Centauri, Nature Communications (2021). DOI: 10.1038/s41467-021-21176-6

https://phys.org/news/2021-02-life-sustaining-planets.html?utm_sour...

Comment by Dr. Krishna Kumari Challa on February 10, 2021 at 11:54am

Prolonged immaturity an evolutionary plus for human babies

Newborn horses can stand within an hour of birth. Baby wood ducks leap from a nest to splash down in a pond a day after hatching. Yet human babies, as well as the young of many other species of mammals and birds, require months or years of care before they reach full mobility and sensory function, let alone maturity.

This prolonged period of immaturity and helplessness – or altriciality – in human babies and other species, long thought to be a drain on resources, is actually an evolutionary advantage, say researchers.

Protracted immaturity and dependence on paternal care is not an unfortunate byproduct of our evolution but instead a highly adaptive trait of our species, which has enabled human infants to efficiently organize attention to social agents and learn efficiently from social output. “The evolutionary goal of altricial species is not to become highly competent as quickly as possible but rather to excel at learning over time.”

Human infants need to acquire complex social skills, including language, empathy, morality and theory of mind. Successful development of these skills depends on information from adults: “Rather than requiring hard-wired, innate knowledge of social abilities, evolution has outsourced the necessary information to parents. Ecologically, prolonged altricial development may give species the ability to adapt to changing or new environments. Humans are especially good at filling new ecological niches because we have the capacity to learn how to survive in new environments. “Once your parents learn an adaptive skill, you’ll learn from them. You don’t have to reinvent the wheel.”

https://news.cornell.edu/stories/2021/02/prolonged-immaturity-evolu...

https://researchnews.cc/news/5049/Prolonged-immaturity-an-evolution...

Comment by Dr. Krishna Kumari Challa on February 10, 2021 at 11:47am

Scientists Invent a Machine That Generates Mathematics We've Never Seen Before

His name was Srinivasa Ramanujan, and he had a unique gift for dreaming up mathematics of a kind few, if any, had ever contemplated.

Attributing his skills to a divine goddess, the Indian mathematician introduced thousands of mathematical ideas and equations to the world, and was especially known for devising conjectures: mathematical propositions not yet proven to be true (in which case they become classified as theorems).

Such an ability – crafting mathematical statements that are both informed and yet uncertain – is rare, and relatively few mathematicians make their name on the basis of such output, let alone theorists with little in the way of formal training.

But now, a new algorithmic invention developed by researchers in Israel could help us automate the discovery of mathematical conjectures like those Ramanujan once pioneered.

Named after Ramanujan – who died in India at the age of 32 – the 'Ramanujan Machine' is a computerised system capable of self-generating conjectures involving mathematical constants: strange numbers like π and e that seem to crop up all over the place, even if entirely by coincidence.

"Fundamental mathematical constants such as e and π are ubiquitous in diverse fields of science, from abstract mathematics and geometry to physics, biology and chemistry," researchers from Technion – Israel Institute of Technology explain in a newly published study detailing the system.

https://www.nature.com/articles/s41586-021-03229-4

https://www.sciencealert.com/scientists-invented-a-machine-that-gen...

Comment by Dr. Krishna Kumari Challa on February 10, 2021 at 11:30am

 Facebook Just Banned More COVID-19 Anti-Vax Content

In a significant move, Facebook has announced it will remove any misleading claims and misinformation about the COVID-19 vaccines from both Facebook and Instagram. It's part of a broader move to help combat fake news about the pandemic. Since December, the platform has been removing claims about the coronavirus that have been debunked by health experts.

But on Monday, the company expanded this policy and are now specifically targeting common anti-vax claims.

This includes claims such as:

• COVID-19 is man-made or manufactured
• Vaccines are not effective at preventing the disease they are meant to protect against
• It's safer to get the disease than to get the vaccine
• Vaccines are toxic, dangerous or cause autism 

Facebook will also be removing fictitious claims that the vaccine will change people's DNA or make them infertile, as well as false claims about where the vaccines are made or their efficacy.

I hope more social networks will follow suit.

https://www.sciencealert.com/big-news-facebook-just-banned-anti-vax...

Comment by Dr. Krishna Kumari Challa on February 10, 2021 at 11:25am

Hormone levels are being used to discriminate against female athletes

Despite slim evidence, testosterone is keeping some women off the field

Hormone Levels Are Being Used to Discriminate against Female Athletes

Despite slim evidence, testosterone is keeping some women off the field

https://www.scientificamerican.com/article/hormone-levels-are-being...

Comment by Dr. Krishna Kumari Challa on February 10, 2021 at 10:29am

The birth of a lightning bolt was caught on video

Behold: the split-second collision of electric currents that creates a flash of lightning. A current reaches down from a cloud. It meets another reaching up from the ground. When a single tenuous thread of electricity bridges the gap between them, lightning flashes.

Comment by Dr. Krishna Kumari Challa on February 10, 2021 at 10:25am

Fossil mimics may be more common in ancient rocks than actual fossils

Abiotic objects that resemble microbes are much hardier than their biological brethren

Actual microbial life-forms are much less likely to become safely fossilized in rocks compared with nonbiological structures that happen to mimic their shapes, new research finds. The finding suggests that Earth’s earliest rocks may contain abundant tiny fakers — minuscule objects masquerading as fossilized evidence of early life — researchers report online January 28 in Geology..

But an even more pernicious and contentious problem is that  tiny filaments or spheres may not be biological in origin at all. Increasingly, scientists have found that nonbiological chemical processes can create similar shapes, suggesting the possibility of “false positives” in the biological record.

https://pubs.geoscienceworld.org/gsa/geology/article/doi/10.1130/G4...

https://www.sciencenews.org/article/fake-fossil-biomorphs-more-comm...

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“biomorphs,” spheres and filaments made of tiny crystals but shaped like bacteria.

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

Human eye beats machine in archaeological color identification test

 A ruler and scale can tell archaeologists the size and weight of a fragment of pottery - but identifying its precise color can depend on individual perception. So, when a handheld color-matching gadget came on the market, scientists hoped it offered a consistent way of determining color, free of human bias.

But a new study by archaeologists at the Florida Museum of Natural History found that the tool, known as the X-Rite Capsure, often misread colors readily distinguished by the human eye.

When tested against a book of color chips, the machine failed to produce correct color scores in 37.5% of cases, even though its software system included the same set of chips. In an analysis of fired clay bricks, the Capsure matched archaeologists' color scores only 35% of the time, dropping to about 5% matching scores when reading sediment colors in the field. Researchers also found the machine was prone to reading color chips as more yellow than they were and sediment and clay as too red.

Identifying subtle differences in color can help archaeologists compare the composition of soil and the origins of artifacts, such as pottery and beads, to understand how people lived and interacted in the past. Color can also reveal whether materials have been exposed to fire, indicating how communities used surrounding natural resources.

https://www.eurekalert.org/pub_releases/2021-02/fmon-heb020921.php

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