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Comment by Dr. Krishna Kumari Challa on June 28, 2020 at 9:57am

King Tut's dagger is made of meteorite's iron!

Daggers, axes and jewelry made from rare iron during the Bronze Age are literally out of this world, according to new research finding that ancient artisans crafted these metal artifacts with iron from outer space carried to Earth by meteorites.

Iron from the Bronze Age are meteoritic, invalidating speculations about precocious [early] smelting during the Bronze Age.

A study using X-ray fluorescence (XRF) spectrometry determined that Tutankhamun’s dagger was made with iron containing nearly 11 percent nickel and traces of cobalt: a characteristic of extraterrestrial iron found in many of the iron meteorites that have rained down on Earth for billions of years.

Most of the iron meteorites that smash into Earth each year are thought to have formed in the metal-heavy cores of planetesimals — small bodies in the protoplanetary disk of debris that orbited the sun during the early stages of the solar system.

As a result, these meteorites contain high levels of nickel or cobalt. In contrast, iron smelted from terrestrial iron ores, which are mined from our planet's outer crust, contain less than 1 percent nickel or cobalt, far less than the levels found in iron-rich space rocks.

Research found no evidence that smelted iron was known until the Iron Age dawned in the Near East, around 1200 B.C.  The oldest-known furnace for smelting iron ore, at Tell Hammeh in Jordan, dates to 930 B.C.

From texts that during the Bronze Age, iron was valued 10 times as much as gold," Jambon said. "[But] in the early Iron Age, the price fell dramatically to less than that of copper, and this is the reason why iron replaced bronze quite rapidly.

https://www.livescience.com/61214-king-tut-dagger-outer-space.html

This work ispublished in the December 2017 issue of the Journal of Archaeological Science.

Comment by Dr. Krishna Kumari Challa on June 28, 2020 at 9:43am

Are eye floaters dangerous? 

Eye Floaters and Flashes

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The story of teeth

Comment by Dr. Krishna Kumari Challa on June 28, 2020 at 7:42am

The science of dust plumes

https://theconversation.com/a-massive-saharan-dust-plume-is-moving-...

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https://www.sciencealert.com/physicists-have-teleported-information...

Physicists Just Quantum Teleported Information Between Particles of Matter

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https://www.nationalgeographic.com/animals/2019/09/zebra-pseudo-mel...

Rare polka dotted zebra foals have a condition called pseudomelanism, a rare genetic mutation in which animals display some sort of abnormality in their stripe pattern.

Zebras also experience other unusual color variations, such as partial albinism. Keeping track of such equine aberrations is useful to science as part of a broader goal to monitor changes in species and how they’re managed by local communities.

Specialized cells called melanocytes produce melanin, the red, yellow, brown, or black pigment that determines hair and skin cell color in mammals.

“There are a variety of mutations that can disturb the process of melanin synthesis, and in all of those disorders, the melanocytes are thought to be normally distributed, but the melanin they make is abnormal.

In zebras, melanocytes are uniformly distributed throughout their skin, so that a shaved zebra would be completely black. In the case of Tira and other pseudomelanistic zebras, experts think the melanocytes are all there, but the melanin itself, for some reason, does not manifest correctly as stripes.

Tira’s future is likely uncertain—most zebras with such unusual coloration probably don’t survive long. Research on other species has shown that, while it is harder for a predator to target an individual in a group, it is easier if an individual is different.

Hurdles for survival: Unfortunately for Tira, recent research  has suggested that zebra stripes evolved to deter against biting flies—one of five theories that have been posed over the years, along with camouflage and temperature regulation. Experiments in the field, for instance, have shown that biting flies don't like landing on striped surfaces.

If that’s the case, Tira won’t be as successful at repelling these flies—which can carry diseases like equine influenza—as a normally striped zebra.

However, if Tira can survive these many hurdles and make it to adulthood, there’s no reason to think he can’t fit into the herd.

Research conducted in South Africa has found that in two cases of plains zebras with aberrant coloring, at least, the animals formed normal relationships with other zebras—including mating.

Comment by Dr. Krishna Kumari Challa on June 27, 2020 at 11:08am

In The Depths of Space, Hubble Sees a Cosmic Bat Beat Its Wings

Comment by Dr. Krishna Kumari Challa on June 27, 2020 at 11:03am

Messengers: Who We Listen To, Who We Don't and Why.

Comment by Dr. Krishna Kumari Challa on June 27, 2020 at 10:31am

Here’s how we’re growing meat in labs instead of in animals

A tissue engineer writes the cultured meat explainer you’ve been looking for

https://massivesci.com/articles/what-is-cultured-meat/?utm_source=d...

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https://massivesci.com/articles/biofabrication-grow-organic-leather...

Lab-grown leather and spider silk are the future of your wardrobe

Burgeoning startups are hacking cells to create ‘unnatural’ and ‘smart’ clothing

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https://www.sciencealert.com/physicists-have-reversed-time-on-the-s...

Physicists Have Reversed Time on The Smallest Scale Using a Quantum Computer

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https://theconversation.com/what-doctors-know-about-lingering-sympt...

lingering symptoms of coronavirus

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https://www.sciencealert.com/new-study-on-breast-implants-finds-tak...

New Study Draws Attention to The Devastating Effects of Breast Implant Illness

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https://phys.org/news/2020-06-km-brazil-megaflash-lightning.html?ut...

700-km Brazil 'megaflash' sets lightning record: UN

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https://phys.org/news/2020-06-conspiracy-theories-emergeand-storyli...

How conspiracy theories emerge—and how their storylines fall apart

Comment by Dr. Krishna Kumari Challa on June 27, 2020 at 8:13am

Jumping kingdoms: What if bacteria jump from plants to humans?

Researchers are learning about new ways  pathogens are jumping from plants to people.

Scientists have been finding "trojan horse" methods bacteria such as salmonella are using to elude plant immune systems and find their way to new human hosts.

Opportunistic bacteria—salmonella, listeria and E.coli, for example—often piggyback on raw vegetables, poultry, beef and other foods to gain entry into a human host, causing millions of foodborne illnesses each year.

But University of Delaware researchers Harsh Bais and Kali Kniel and their collaborators now have found that wild strains of salmonella can circumvent a plant's immune defense system, getting into the leaves of lettuce by opening up the plant's tiny breathing pores called stomates.

The plant shows no symptoms of this invasion and once inside the plant, the pathogens cannot just be washed off.

Stomates are little kidney-shaped openings on leaves that open and close naturally and are regulated by circadian rhythm. They open to allow the plant to cool off and breathe. They close when they detect threats from drought or plant bacterial pathogens.

Some pathogens can barge into a closed stomate using brute force. Fungi can do that, for example. Bacteria don't have the enzymes needed to do that so they look for openings—in roots or through stomates. Plant bacterial pathogens have found a way to reopen those closed stomates and gain entry to the plant's internal workings. 

But now, in research published by Frontiers in Microbiology, Bais and Kniel have shown that some strains of the human pathogen salmonella have developed a way to reopen closed stomates, too.

What's new is how the non-host bacteria are evolving to bypass plant immune response. They are real opportunists. They are absolutely jumping kingdoms….When we see these unusual interactions, that's where it starts to get complex.

Opportunities for pathogens arise as plants are bred to increase yield, often at the expense of their own defense systems. Other opportunities arise when a grower plants low-lying crops too close to a livestock field, making contamination easier.

Nicholas Johnson et al. Evasion of Plant Innate Defense Response by Salmonella on Lettuce, Frontiers in Microbiology (2020). DOI: 10.3389/fmicb.2020.00500

https://phys.org/news/2020-06-bacteria-ways-immune-defenses.html?ut...

Comment by Dr. Krishna Kumari Challa on June 27, 2020 at 7:03am

Eco-cultural identity explained ...

https://phys.org/news/2020-06-ecocultural-identity.html?utm_source=...

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https://phys.org/news/2020-06-lab-cartilage-mimicking-gel-strong-kn...

From the lab, the first cartilage-mimicking gel that's strong enough for knees

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Comparing 13 different CRISPR-Cas9 DNA scissors

https://phys.org/news/2020-06-crispr-cas9-dna-scissors.html?utm_sou...

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https://theconversation.com/kissing-can-be-dangerous-how-old-advice...

When Kissing can be dangerous ....

Comment by Dr. Krishna Kumari Challa on June 27, 2020 at 6:51am

How an intelligent alien civilization can harvest energy from blackholes

https://theconversation.com/could-we-extract-energy-from-a-black-ho...

Comment by Dr. Krishna Kumari Challa on June 27, 2020 at 6:25am

Gender bias kept alive by people who think it's dead

Workplace gender bias is being kept alive by people who think it's no longer an issue, new research suggests.

In the study, managers were given identical descriptions of a worker—the only difference being either a male or female name.

Most managers rated the male worker as more competent, and recommended a higher salary—an average 8% pay gap.

The "key drivers" of this gap were managers who thought bias no longer existed in their profession, while those who believed bias still existed recommended roughly equal pay.

This means holding this belief constitutes a "critical risk factor", and may be vital to identifying who in a profession is perpetuating issues of gender bias.

Two thirds of the managers who thought gender bias no longer existed were men—but female managers with this opinion undervalued female staff just as much as male managers did.

The research -by the University of Exeter, Skidmore College and the British Veterinary Association (BVA) - focussed on the veterinary profession. The resulting evaluations were systematically biased among those who thought gender bias was no longer an issue.

The studies also found:

• Vets were split over whether gender bias still existed in their profession (44% said yes, 42% said no; the rest were undecided).
• Gender bias among managers who thought bias was not an issue was not only evident among those who strongly believed this, but also those who only slightly held this view.
• Because of seeing the female as less competent, managers were also less likely to advise giving her more managerial responsibilities, and less likely to encourage her to pursue important opportunities for promotion. This shows how managers' biases not only affect women's current employment situation (current pay) but can affect the entire trajectory of their career, by discouraging them from pursuing promotions.
• All of these effects held true when controlling for managers' own gender, their years of managerial experience, how long they've been in the profession, etc.
• They also held true when controlling for managers' endorsement of more overtly sexist beliefs (i.e., endorsement of hostile sexism)

this research highlights a rather insidious paradox that can arise when individuals misperceive the level of progress made on gender equality in their profession, such that those who mistakenly think gender bias is no longer an issue become the highest risk for perpetuating it.

C.T. Begeny el al., "In some professions, women have become well represented, yet gender bias persists—Perpetuated by those who think it is not happening," Science Advances (2020). advances.sciencemag.org/lookup … .1126/sciadv.aba7814

https://phys.org/news/2020-06-gender-bias-alive-people-dead.html?ut...

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