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Comment by Dr. Krishna Kumari Challa on June 29, 2020 at 10:22am

Moth mimicry

Comment by Dr. Krishna Kumari Challa on June 29, 2020 at 8:29am

Four new species of giant single-celled organisms discovered on Pacific seafloor

https://phys.org/news/2020-06-species-giant-single-celled-pacific-s...

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Ancient Maya reservoirs too contained toxic pollution: study

https://phys.org/news/2020-06-ancient-maya-reservoirs-toxic-polluti...

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https://www.howitworksdaily.com/can-anything-withstand-the-immense-...

Can anything withstand the immense heat of the Sun?

The Sun is surrounded by a layer of plasma which extends millions of miles into space, in some places reaching up to 3 million degrees Celsius (5.4 million degrees Fahrenheit).

There are no known materials that can exist as solids, liquids or gases at such extreme temperatures.

Protons, neutrons and electrons can withstand this heat as they are virtually indestructible, however they can only exist as plasma.

If you could somehow get past the corona to the surface of the Sun, where it is ‘only’ 5,500 degrees Celsius (9,900 degrees Fahrenheit), some liquids could exist.

Comment by Dr. Krishna Kumari Challa on June 29, 2020 at 8:25am

Rewriting science text books: From blue electrolyte to bronze metal:Researchers have has succeeded in mapping at the molecular level the electrolyte-to-metal transition in alkali metal – liquid ammonia solutions using a combination of photoelectron spectroscopy (PES) and electronic structure calculations

Comment by Dr. Krishna Kumari Challa on June 29, 2020 at 8:07am

The right way to breathe during the coronavirus pandemic:

Inhale through your nose and exhale through your mouth. 

The reason is that your nasal cavities produce the molecule nitric oxide, which chemists abbreviate NO, that increases blood flow through the lungs and boosts oxygen levels in the blood. Breathing in through the nose delivers NO directly into the lungs, where it helps fight coronavirus infection by blocking the replication of the coronavirus in the lungs.

The higher oxygen saturation of the blood can make one feel more refreshed and provides greater endurance.

Nitric oxide is a widespread signaling molecule that triggers many different physiological effects. It is also used clinically as a gas to selectively dilate the pulmonary arteries in newborns with pulmonary hypertension. Unlike most signaling molecules, NO is a gas in its natural state.

NO is produced continuously by the 1 trillion cells that form the inner lining, or endothelium, of the 100,000 miles of arteries and veins in our bodies, especially the lungs. Endothelium-derived NO acts to relax the smooth muscle of the arteries to prevent high blood pressure and to promote blood flow to all organs. Another vital role of NO is to prevent blood clots in normal arteries.

In addition to relaxing vascular smooth muscle, NO also relaxes smooth muscle in the airways – trachea and bronchioles – making it easier to breathe. Another type of NO-mediated smooth muscle relaxation occurs in the erectile tissue (corpus cavernosum), which results in penile erection. In fact, NO is the principal mediator of penile erection and sexual arousal. This discovery led to the development and marketing of  sildenafil ( Viagra), which works by enhancing the action of NO.

Other types of cells in the body, including circulating white blood cells and tissue macrophages, produce nitric oxide for antimicrobial purposes. The NO in these cells reacts with other molecules, also produced by the same cells, to form antimicrobial agents to destroy invading microorganisms including bacteria, parasites and viruses. As you can see, NO is quite an amazing molecule.

Since NO is a gas, it can be administered with the aid of specialized devices as a therapy to patients by inhalation. Inhaled NO is used to treat infants born with 

persistent pulmonary hypertension, a condition in which constricted pulmonary arteries limit blood flow and oxygen harvesting.

Inhaled NO dilates the constricted pulmonary arteries and increases blood flow in the lungs. As a result, the red blood cell hemoglobin can extract more lifesaving oxygen and move it into the general circulation. Inhaled NO has literally turned blue babies pink and allowed them to be cured and to go home with mom and dad. Before the advent of inhaled NO, most of these babies died.

Inhaled NO is currently in clinical trials for the treatment of patients with Covid 19.

https://theconversation.com/the-right-way-to-breathe-during-the-cor...

Comment by Dr. Krishna Kumari Challa on June 29, 2020 at 7:49am

Aphantasia: People Who Can't See Things in Their Mind Could Have Memory Trouble Too, Study Finds

Not everyone can see pictures in their minds when they close their eyes and summon thoughts - an ability many of us take for granted.

While people have been aware of this phenomenon since the 1800s, it hasn't been widely studied, and was only recently named 'aphantasia'. This absence of voluntarily generated mental visual imagery is thought to be experienced by 2-5 percent of the population.

Recent studies suggest aphantasia is indeed a lack of visual imagery rather than the lack of awareness of having internal visual imagery - with some people experiencing loss of this ability after injuries.

Now new research has revealed that aphantasics also have other cognitive differences.

it was found that aphantasia isn't just associated with absent visual imagery, but also with a widespread pattern of changes to other important cognitive processes.

People with aphantasia reported a reduced ability to remember the past, imagine the future, and even dream. This suggests that visual imagery might play a key role in memory processes. 

Not only did aphantasics dream less often, their dreams were less vivid and had lower sensory details. 

"This suggests that any cognitive function involving a sensory visual component – be it voluntary or involuntary – is likely to be reduced in aphantasia. 

Some of those with aphantasia also reported decreased imagining with other senses.

"Our data also showed that individuals with aphantasia not only report being unable to visualise, but also report comparatively reduced imagery, on average, in all other sensory modalities, including auditory, tactile, kinesthetic, taste, olfactory and emotion.

This backs up personal reports from aphantasics exploring their own experiences with aphantasia. Aphantasic Alan Kendle shares the moment he realised that, unlike him, other people can hear music playing in their minds.

But not all of those with visual aphantasia had their other sensory imaginings missing, suggesting variations in this way of experiencing our inner minds.

https://www.nature.com/articles/s41598-020-65705-7

https://www.sciencealert.com/some-people-can-t-picture-things-in-th...

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.

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