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Comment by Dr. Krishna Kumari Challa on August 27, 2020 at 5:44am

Microscopic robots 'walk' thanks to laser tech

https://techxplore.com/news/2020-08-microscopic-robots-laser-tech.h...

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Meteorite strikes may create unexpected form of silica

When a meteorite hurtles through the atmosphere and crashes to Earth, how does its violent impact alter the minerals found at the landing site? What can the short-lived chemical phases created by these extreme impacts teach scientists about the minerals existing at the high-temperature and pressure conditions found deep inside the planet?

Quartz is made up of one silicon atom and two oxygen atoms arranged in a tetrahedral lattice structure. Because these elements are also common in the silicate-rich mantle of the Earth, discovering the changes quartz undergoes at high-pressure and -temperature conditions, like those found in the Earth's interior, could also reveal details about the planet's geologic history.

When a material is subjected to extreme pressures and temperatures, its internal atomic structure can be re-shaped, causing its properties to shift. For example, both graphite and diamond are made from carbon. But graphite, which forms at low pressure, is soft and opaque, and diamond, which forms at high pressure, is super-hard and transparent. The different arrangements of carbon atoms determine their structures and their properties, and that in turn affects how we engage with and use them.

when subjected to a dynamic shock of greater than 300,000 times normal atmospheric pressure, quartz undergoes a transition to a novel disordered crystalline phase, whose structure is intermediate between fully crystalline stishovite and a fully disordered glass. However, the new structure cannot last once the burst of intense pressure has subsided.

"Structural response of α-quartz under plate-impact shock compression" Science Advances (2020). advances.sciencemag.org/lookup … .1126/sciadv.abb3913

https://phys.org/news/2020-08-meteorite-unexpected-silica.html?utm_...

Comment by Dr. Krishna Kumari Challa on August 27, 2020 at 5:43am

Cosmic rays may soon hinder the progress of quantum computing

The practicality of quantum computing hangs on the integrity of the quantum bit, or qubit. That  depends on a qubit's integrity, or how long it can operate before its superposition and the quantum information are lost—a process called decoherence, which ultimately limits the computer run-time. Superconducting qubits—a leading qubit modality today—have achieved exponential improvement in this key metric, from less than one nanosecond in 1999 to around 200 microseconds today for the best-performing devices.

have found that a qubit's performance will soon hit a wall. In a paper published in Nature, the team reports that the low-level, otherwise harmless background radiation that is emitted by trace elements in concrete walls and incoming cosmic rays are enough to cause decoherence in qubits. They found that this effect, if left unmitigated, will limit the performance of qubits to just a few milliseconds. 

 There are many sources of decoherence that could destabilize a qubit, such as fluctuating magnetic and electric fields, thermal energy, and even interference between qubits.

Scientists have long suspected that very low levels of radiation may have a similar destabilizing effect in qubits.

In new experiments scientists found this is true and shielding improved qubit performance.

Source: Impact of ionizing radiation on superconducting qubit coherence, Nature (2020). DOI: 10.1038/s41586-020-2619-8 , www.nature.com/articles/s41586-020-2619-8

https://phys.org/news/2020-08-cosmic-rays-stymie-quantum.html?utm_s...

Comment by Dr. Krishna Kumari Challa on August 26, 2020 at 8:12am

Scientific research video

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crazy science

Comment by Dr. Krishna Kumari Challa on August 26, 2020 at 5:52am

New treatments aim to treat COVID-19 early, before it gets serious

https://www.sciencenews.org/article/coronavirus-covid-19-new-early-...

Some promising treatments may block the coronavirus from entering cells or from multiplying

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Disease Tolerance: Why Do Some People Weather Coronavirus Infection Unscathed?

https://www.scientificamerican.com/article/why-do-some-people-weath...

https://undark.org/2020/08/24/covid-19-infection-asymptomatic/

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Two major microbial groups living deep underground can't breathe

A new scientific study has revealed unique life strategies of two major groups of microbes that live below Earth's surface. These groups, originally thought to rely on symbiotic relationships with other organisms, may also live independently and use an ancient mode of energy production.

https://www.sciencedaily.com/releases/2020/08/200825110626.htm

Comment by Dr. Krishna Kumari Challa on August 26, 2020 at 5:44am

Reverse dieting: slowly increasing calories won’t prevent weight regain – but may have other benefits

https://theconversation.com/reverse-dieting-slowly-increasing-calor...  

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India is key for global access to a COVID-19 vaccine – here’s why

https://theconversation.com/india-is-key-for-global-access-to-a-cov...  

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Cold-Causing Coronaviruses Don’t Seem to Confer Lasting Immunity

Studies on SARS-CoV-2’s milder cousins hint that our immune systems are quick to forget the viruses, but it’s unclear whether the same is true for the agent that causes COVID-19.

https://www.the-scientist.com/news-opinion/cold-causing-coronavirus...

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The puzzle in measurement of positronium’s energy levels

A new measurement of the exotic “atom” — consisting of an electron and its antiparticle, a positron — disagrees with theoretical calculations, scientists report

Positronium is composed of an electron, with a negative charge, circling in orbit with a positron, with a positive charge — making what’s effectively an atom without a nucleus (SN: 9/12/07). With just two particles and free from the complexities of a nucleus, positronium is appealingly simple. Its simplicity means it can be used to precisely test the theory of quantum electrodynamics, which explains how electrically charged particles interact.

https://www.sciencenews.org/article/positronium-energy-levels-exoti...

Comment by Dr. Krishna Kumari Challa on August 26, 2020 at 5:32am

Ancient star explosions revealed in the deep sea

A mystery surrounding the space around our solar system is unfolding thanks to evidence of supernovae found in deep-sea sediments.

A new study  shows the Earth has been traveling for the last 33,000 years through a cloud of faintly radioactive dust.

These clouds could be remnants of previous supernova explosions, a powerful and super bright explosion of a star.

The researchers searched through several deep-sea sediments from two different locations that date back 33,000 years using the extreme sensitivity of HIAF's mass spectrometer. They found clear traces of the isotope iron-60, which is formed when stars die in supernova explosions.

Iron-60 is radioactive and completely decays away within 15 million years, which means any iron-60 found on the earth must have been formed much later than the rest of the 4.6-billion-year old earth and arrived here from nearby supernovae before settling on the ocean floor.

found traces of iron-60 at about 2.6 million years ago, and possibly another at around 6 million years ago, suggesting earth had traveled through fallout clouds from nearby supernovae.

For the last few thousand years the solar system has been moving through a denser cloud of gas and dust, known as the local interstellar cloud, (LIC), whose origins are unclear. If this cloud had originated during the past few million years from a supernova, it would contain iron-60, and so the team decided to search more recent sediment to find out.

Sure enough, there was iron-60 in the sediment at extremely low levels—equating to radioactivity levels in space far below the Earth's natural background levels—and the distribution of the iron-60 matched earth's recent travel through the local interstellar cloud. But the iron-60 extended further back and was spread throughout the entire 33,000 year measurement period.

The lack of correlation with the solar system's time in the current local interstellar cloud seems to pose more questions than it answers. Firstly, if the cloud was not formed by a supernova, where did it come from? And secondly, why is there iron-60 so evenly spread throughout space?

There are recent papers that suggest iron-60 trapped in dust particles might bounce around in the interstellar medium.

So the iron-60 could originate from even older supernovae explosions, and what we measure is some kind of echo. More data is required to resolve these details.

A. Wallner et al. 60Fe deposition during the late Pleistocene and the Holocene echoes past supernova activity, Proceedings of the National Academy of Sciences (2020). DOI: 10.1073/pnas.1916769117

https://phys.org/news/2020-08-ancient-star-explosions-revealed-deep...

Comment by Dr. Krishna Kumari Challa on August 26, 2020 at 5:27am

Galactic bar paradox resolved in cosmic dance

New light has been shed on a mysterious and long-standing conundrum at the very heart of our galaxy. The new work offers a potential solution to the so-called "Galactic bar paradox," whereby different observations produce contradictory estimates of the motion of the central regions of the Milky Way.

The majority of spiral galaxies, like our home the Milky Way, host a large bar-like structure of stars in their center. Knowledge of the true bar size and rotational speed is crucial for understanding how galaxies form and evolve, as well as how they form similar bars throughout the universe.

However our galaxy's bar size and rotational speed have been strongly contested in the last 5 years; while studies of the motions of stars near the Sun find a bar that is both fast and small, direct observations of the Galactic central region agree on one that is significantly slower and larger.

The new study, by an international team of scientists suggests an insightful solution to this discrepancy. Analyzing state-of-the-art galaxy formation simulations of the Milky Way, they show that both the bar's size and its rotational speed fluctuate rapidly in time, causing the bar to appear up to twice as long and rotate 20 percent faster at certain times.

The bar pulsations result from its regular encounters with the Galactic spiral arms, in what can be described as a "cosmic dance." As the bar and spiral arm approach each other, their mutual attraction due to gravity makes the bar slow down and the spiral speed up. Once connected, the two structures move as one and the bar appears much longer and slower than it actually is. As the dancers split apart, the bar speeds up while the spiral slows back down.

T Hilmi et al. Fluctuations in galactic bar parameters due to bar–spiral interaction, Monthly Notices of the Royal Astronomical Society (2020). DOI: 10.1093/mnras/staa1934

https://phys.org/news/2020-08-galactic-bar-paradox-cosmic.html?utm_...

Comment by Dr. Krishna Kumari Challa on August 26, 2020 at 5:10am

New imaging technique helps resolve nanodomains, chemical composition in cell membranes

Jin Lu et al. Single‐Molecule 3D Orientation Imaging Reveals Nanoscale Compositional Heterogeneity in Lipid Membranes, Angewandte Chemie International Edition (2020). DOI: 10.1002/anie.202006207

https://phys.org/news/2020-08-imaging-technique-nanodomains-chemica...

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Nanoengineered biosensors for early disease detection

Researchers have developed a cheaper, faster and ultrasensitive biosensors that use nanoengineered porous gold which more effectively detect early signs of disease, improving patient outcomes. This new diagnostic technique allows for direct detection of disease-specific miRNA, which wasn't previously possible.

This is especially important for patients at an early stage of a disease such as cancer, who do not have detectable amounts of other biomarkers, but may have a detectable quantity of exosomal miRNA biomarker.

The platform was nanoengineered by the team to read samples of blood, urine, saliva or plasma through a surface covered in a gold film, which has millions of tiny pores.

Hyunsoo Lim et al. A universal approach for the synthesis of mesoporous gold, palladium and platinum films for applications in electrocatalysis, Nature Protocols (2020). DOI: 10.1038/s41596-020-0359-8

https://phys.org/news/2020-08-nanoengineered-biosensors-early-disea...

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Physicists discover new two-dimensional ferroelectric material just two atoms thick

Two-dimensional materials are ultrathin membranes that hold promise for novel optoelectronic, thermal, and mechanical applications, including ultra-thin data-storage devices that would be both foldable and information dense.

Ferroelectric materials are those with an intrinsic dipole moment—a measure of the separation of positive and negative charges—that can be switched by an electric field.

Salvador Barraza-Lopez et al. Water Splits To Degrade Two-Dimensional Group-IV Monochalcogenides in Nanoseconds, ACS Central Science (2018). DOI: 10.1021/acscentsci.8b00589

https://phys.org/news/2020-08-physicists-two-dimensional-material.h...

Comment by Dr. Krishna Kumari Challa on August 25, 2020 at 8:16am

The False Logic behind Science Denial

Those who argue that COVID-19 isn’t a real threat are mirroring bogus attacks on global warming and evolution

https://www.scientificamerican.com/article/the-false-logic-behind-s...  

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How Birds Evolved Their Incredible Diversity

An analysis of 391 skulls shows that birds evolved surprisingly slowly, compared with their dinosaur forerunners

https://www.scientificamerican.com/article/how-birds-evolved-their-...

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Origami-inspired miniature manipulator improves precision and control of teleoperated surgical procedures

https://techxplore.com/news/2020-08-origami-inspired-miniature-prec...

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** 'Earth breathing': mountain erosion a missing piece in the climate puzzle

https://phys.org/news/2020-08-earth-mountain-erosion-piece-climate....

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Digging your own digital grave: How should you manage the data you leave behind?

https://techxplore.com/news/2020-08-digital-grave.html?utm_source=n...

Comment by Dr. Krishna Kumari Challa on August 25, 2020 at 7:59am

Scientists Are Figuring Out What Happens in The Skin When You Have Eczema

Scientists have pinpointed a bunch of processes that go wrong in the skin for people who have eczema (also known as atopic dermatitis), and it could help us figure out how to combat this chronic condition.

Earlier, researchers found a strong link between people lacking in a certain skin protein, and the risk of developing eczema. And in 2017, scientists built on those results to show exactly what goes wrong, and their results could even take us closer to an eczema cure.

For the past decade, scientists have known that eczema is associated with a genetic lack of filaggrin (filament aggregating protein) in the skin. This protein helps shape individual skin cells, and plays an important role in our skin's barrier function.

If a person has a genetic mutation that prevents proper filaggrin supply, they can develop skin conditions such as eczema or ichthyosis vulgaris, where skin cells don't shed, and instead pile up in a pattern that looks like fish scales.

But until recently, researchers weren't sure how eczema actually develops when filaggrin is lacking.

The breakthrough came in 2016, when scientists from Newcastle University in the UK in collaboration with GSK Stiefel tracked down a series of proteins and molecular pathways that lead to this insufferable skin problem.

They found that this deficiency alone could trigger a host of molecular changes in important regulatory mechanisms in the skin. This affected things like cell structure, barrier function, and even how cells got inflamed and responded to stress

They found that several of the proteins they detected were similarly altered in only those with eczema - just like the lab-based model had demonstrated.

Once scientists know for sure what goes on in the skin if you have the faulty filaggrin gene, they can start looking for drugs that can stop that from happening.

The study was published in the Journal of Allergy and Clinical Immunology.

https://www.sciencealert.com/scientists-are-figuring-out-what-happe...

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