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Comment by Dr. Krishna Kumari Challa on July 16, 2020 at 6:39am

Bacteria with a metal diet discovered in dirty glassware

Microbiologists have discovered bacteria that feed on manganese and use the metal as their source of calories. Such microbes were predicted to exist over a century ago, but none had been found or described until now.

The study also reveals that the bacteria can use manganese to convert carbon dioxide into biomass, a process called chemosynthesis. Previously, researchers knew of bacteria and fungi that could oxidize manganese, or strip it of electrons.

Researchers found the bacteria serendipitously after performing unrelated experiments using a light, chalk-like form of manganese. They had left a glass jar soiled with the substance to soak in tap water in their  office sink before departing for several months to work off campus. When they returned, the jar was coated with a dark material.

They wondered, 'What is that?' and systematically performed tests to figure that out.

The black coating was in fact oxidized manganese generated by newfound bacteria that had likely come from the tap water itself. There is evidence that relatives of these creatures reside in groundwater.

Manganese is one of the most abundant elements on the surface of the earth. Manganese oxides take the form of a dark, clumpy substance and are common in nature; they have been found in subsurface deposits and can also form in water-distribution systems.

There is a whole set of environmental engineering literature on drinking-water-distribution systems getting clogged by manganese oxides. But how and for what reason such material is generated there has remained an enigma. Clearly, many scientists have considered that bacteria using manganese for energy might be responsible, but evidence supporting this idea was not available until now.

The finding helps researchers better understand the geochemistry of groundwater. It is known that bacteria can degrade pollutants in groundwater, a process called bioremediation. When doing this, several key organisms will "reduce" manganese oxide, which means they donate electrons to it, in a manner similar to how humans use oxygen in the air. Scientists have wondered where the manganese oxide comes from in the first place.

The bacteria discovered now can produce it, thus they enjoy a lifestyle that also serves to supply the other microbes with what they need to perform reactions that we consider to be beneficial and desirable.

The research findings also have possible relevance to understanding manganese nodules that dot much of the seafloor.

Bacterial chemolithoautotrophy via manganese oxidation, Nature (2020). DOI: 10.1038/s41586-020-2468-5

https://phys.org/news/2020-07-bacteria-metal-diet-dirty-glassware.h...

Comment by Dr. Krishna Kumari Challa on July 15, 2020 at 11:24am

Researchers discover how cells remember infections decades later

https://phys.org/news/2017-12-cells-infections-decades.html

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An exploding white dwarf star blasted itself out of its orbit with another star in a "partial supernova" and is now hurtling across our galaxy, according to a new study from the University of Warwick.

https://phys.org/news/2020-07-blast-star-hurtling-milky.html?utm_so...

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https://phys.org/news/2020-07-scientists-uncover-key-ribosomes-prot...

Scientists uncover key process in the manufacture of ribosomes and proteins

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Scientists discover heavy element chemistry can change at high pressures

New research shows that one of the heaviest known elements can be manipulated to a greater degree than previously thought, potentially paving the way for new strategies to recycle nuclear fuel and better long-term storage of radioactive elements.

https://phys.org/news/2020-07-fsu-news-scientists-heavy-element.htm...

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https://phys.org/news/2020-07-true-scientists-discuss-evolution-whi...

Scientists discuss evolution of white coloration of velvet ants

Comment by Dr. Krishna Kumari Challa on July 15, 2020 at 11:16am

Ex-Harvard Medical School faculty member warns COVID-19 herd immunity is ‘wishful thinking'

A Washington D.C.-based internist and former Harvard Medical School faculty member has claimed the idea that herd immunity may slow the coronavirus pandemic is "wishful thinking" after a 50-year-old patient was infected for a second time with COVID-19.

"During his first infection, my patient experienced a mild cough and sore throat," Dr. Clay Ackerly explained in an opinion piece for Vox. "His second infection, in contrast, was marked by a high fever, shortness of breath, and hypoxia, resulting in multiple trips to the hospital.

"It is possible, but unlikely, that my patient had a single infection that lasted three months," Dr. Ackerly added. "Some Covid-19 patients (now dubbed 'long haulers') do appear to suffer persistent infections and symptoms.

"My patient, however, cleared his infection — he had two negative PCR tests after his first infection — and felt healthy for nearly six weeks."

Typically, experts estimate that between 70 and 90 percent of a population must be immune to a contagious disease to achieve herd immunity -- whether through vaccination or other exposure to an infection.

However, a recent study in Spain, one of the countries hardest-hit by the pandemic, found just five percent of those surveyed had coronavirus antibodies. On a regional basis, the percentage varied from fewer than three percent in coastal regions to more than 10 percent in areas around Madrid.

https://www.foxnews.com/health/clay-ackerly-coronavirus-herd-immuni...

"My patient caught Covid-19 twice. So long to herd immunity hopes?" (Vox, 7/12/20) - original article

Comment by Dr. Krishna Kumari Challa on July 15, 2020 at 9:11am

One in Three Young Adults at Risk of Severe Coronavirus Infections, Study Finds

certain factors that can put anyone at risk of serious illness, regardless of age. A new study from researchers at the University of California, San Francisco determined that one in three young adults ages 18 to 25 are vulnerable to severe COVID-19 cases.

Patients were considered vulnerable if they had least one risk factor, including a smoking habit or chronic illness like heart disease, diabetes, asthma, obesity, autoimmune disease, or liver problems.

https://www.sciencealert.com/smoking-may-explain-why-1-in-3-young-a...

Comment by Dr. Krishna Kumari Challa on July 15, 2020 at 7:07am

 Scientists investigate radiolabeling of calcium carbonate particles in vivo

https://phys.org/news/2020-07-scientists-radiolabeling-calcium-carb...

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 https://phys.org/news/2020-07-road-traffic-microplastics-world-ocea...

Road traffic microplastics flooding world's oceans: study

Researchers find sun and rain transform asphalt binder into potentially toxic compounds

https://phys.org/news/2020-07-sun-asphalt-binder-potentially-toxic....

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https://phys.org/news/2020-07-air-pollution-affects-brain.html?utm_...

Air pollution affects brain development, but when does the damage start?

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https://phys.org/news/2020-07-cloud-hidden-greenhouse-gas-emissions...

Cloud computing could be producing hidden greenhouse gas emissions

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https://techxplore.com/news/2020-07-codes-smartphone-easily.html?ut...

'Knock codes' for smartphone security are easily predicted, researchers say

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https://www.sciencenews.org/article/time-universe-fundamental-cosmi...

The universe might have a fundamental clock that ticks very, very fast

Time could be the result of particles interacting with a ticking cosmic timepiece

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https://www.sciencealert.com/a-giant-wall-of-galaxies-has-been-foun...

A Giant 'Wall' of Galaxies Has Been Found Stretching Across The Universe

Comment by Dr. Krishna Kumari Challa on July 15, 2020 at 6:26am

Why does some frogs' skin colour  appear green? 

Frogs and toads are green for a very good reason—it makes them harder to see in their leafy environments. Good camouflage allows them to eat and not be eaten. But not all frogs have arrived at this life-saving greenness in the same way.

Most of these animals rely on color-controlling structures in their skin called chromatophores that use crystals to bend light to specific colors and make them appear green. But there are hundreds of species of frogs and toads that have nearly translucent skin and very few chromatophores.

Their greenness, which can be found deep in their lymphatic fluid, soft tissues and even bones, comes from a clever biochemical workaround that combines a normally virus-fighting type of protein with a toxic byproduct of blood breakdown.

many of these frogs contain very high levels of bile pigment called biliverdin that is a byproduct of breaking apart old red blood cells. This pigment is normally considered a toxin to be filtered out in the liver and excreted as quickly as possible. But these frogs are found to carry four times as much biliverdin as even the sickest human with liver disease, and 200 times as much as their chromatophore-equipped frog cousins.

When you see something green, its color really should be called 'everything but green,' because it is soaking up all the colors of incoming light except for green. The color we see is the frequency of light it does not absorb that bounces back to our eyes.

Biliverdin by itself would appear to be somewhat greenish, as sometimes seen in an old bruise, but the researchers found that a bound serpin, BBS, stretches out biliverdin's helical shape to fine-tune its light absorbance, making it more cyan, a blue-green. Cyan, added to some other yellow pigments scattered in the skin, bounces back just the right shade of green. It also makes biliverdin less toxic as well.

This new protein has the same spectroscopic properties or light absorption properties as some plant pigments.

So this is a convergence in evolution. Being arboreal (living in trees), they developed a different way to make their coloration. This shows how natural selection can co-opt proteins for just about any purpose.

Source: Carlos Taboada et al, Multiple origins of green coloration in frogs mediated by a novel biliverdin-binding serpin, Proceedings of the National Academy of Sciences (2020). DOI: 10.1073/pnas.2006771117

https://phys.org/news/2020-07-green-skin-deep-hundreds-frog-species...

Comment by Dr. Krishna Kumari Challa on July 14, 2020 at 11:36am

https://theconversation.com/heres-how-scientists-know-the-coronavir...

Here’s how scientists know the coronavirus came from bats and wasn’t made in a lab

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A brain-inspired architecture for human gesture recognition

https://techxplore.com/news/2020-07-brain-inspired-architecture-hum...

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https://phys.org/news/2020-07-burrowing-crabs-reshaping-salt-marshe...

**Burrowing crabs reshaping salt marshes, with climate change to blame

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https://phys.org/news/2020-07-scientists-fault-southeastern-nepal.h...

**Scientists discover fault system in southeastern Nepal

Comment by Dr. Krishna Kumari Challa on July 14, 2020 at 10:45am

** Andean condors, at 10kg or more, are among the world’s heaviest flying birds. Once birds get this big, the energetic costs of flapping are so high they instead rely on currents of rising air to travel long distances.

on average, condors fly for three hours a day, but they flap for less than two minutes of this – just 1% of their flight time. One bird even flew for more than five hours without a single flap, covering 172km. Surprisingly, the amount they flapped hardly changed whether they were in the Andes or the steppe, or whether it was windy or not.

Moving between weak thermals of air seemed more challenging as birds flapped towards the end of the glides, when they were likely to be close to the ground. This is a critical time as birds need to find rising air to avoid an unplanned landing.

Thermals can behave like lava lamps, with bubbles of air rising intermittently from the ground when the air is warm enough. Birds may therefore arrive in the right place for a thermal, but at the wrong time. And the lengths of time when the bubbles are not rising sufficiently rapidly to be useful to a condor will be longer when thermals are weaker.

Nonetheless, even in weak thermal conditions, which may occur in winter, our results suggest condors may flap for only around two seconds per km. This remarkably low investment in flapping flight is on a par with albatrosses. In fact, albatrosses appear to flap more than condors – between (1% and 15% of their flight time outside take-off) –although it is unclear how their overall energy expenditure compares.

What is particularly striking about this findings is that all the birds teh researchers studied were immature. There was some suggestion that flight performance improved with age, but the demonstration that all birds flap so rarely shows that it is possible for even young condors to invest little energy in flying.

https://theconversation.com/we-tagged-andean-condors-to-find-out-ho...

Comment by Dr. Krishna Kumari Challa on July 14, 2020 at 10:17am

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Blood Transplants from Active Mice Give Brain Boost to Others

The researchers behind the results propose that an exercise-induced protein in circulation is responsible for the benefits.

https://www.the-scientist.com/news-opinion/blood-transplants-from-a...

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Comment by Dr. Krishna Kumari Challa on July 14, 2020 at 9:04am

 What happens if you ignore science, fall prey for conspiracy theories, think what scientists say are hoax theories? 

A man learnt the lesson in his final moments .... sadly at the cost of his life. 

'I thought this was a hoax': Patient in 30s dies after attending 'COVID party'

Coronavirus Is What You Get When You Ignore Science

https://news4sanantonio.com/news/local/i-thought-this-was-a-hoax-pa...

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https://theconversation.com/one-vaccine-to-beat-covid-sars-mers-and...

 One vaccine to beat COVID, Sars, Mers and common cold – possible?

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The next pandemic: The warnings are clear – more diseases will follow the coronavirus pandemic.

https://www.scidev.net/global/spotlight/the-next-pandemic.html?utm_...

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 Wriggling Roundworm Found in Woman's Tonsil After She Ate Sashimi

Eating raw meat of any kind carries with it a risk of parasites, but few are as well known as those found in sashimi. The Japanese delicacy can infect the eater with a number of unpleasant aquatic parasites.

https://www.sciencealert.com/a-wriggling-moulting-roundworm-was-fou...

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