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Comment by Dr. Krishna Kumari Challa on March 16, 2023 at 12:19pm

Where did Earth's water come from? Not melted meteorites, according to scientists

Water makes up 71% of Earth's surface, but no one knows how or when such massive quantities of water arrived on Earth.

A new study published in the journal Nature brings scientists one step closer to answering that question.

Researchers analyzed melted meteorites that had been floating around in space since the solar system's formation 4 1/2 billion years ago. They found that these meteorites had extremely low water content—in fact, they were among the driest extraterrestrial materials ever measured. These results, which let researchers rule them out as the primary source of Earth's water, could have important implications for the search for water—and life—on other planets. It also helps researchers understand the unlikely conditions that aligned to make Earth a habitable planet.

After analyzing the achondrite meteorite samples, researchers discovered that water comprised less than two millionths of their mass. For comparison, the wettest meteorites—a group called carbonaceous chondrites—contain up to about 20% of water by weight, or 100,000 times more than the meteorite samples.

This means that the heating and melting of planetesimals leads to near-total water loss, regardless of where these planetesimals originated in the solar system and how much water they started out with. Researchers discovered that, contrary to popular belief, not all outer solar system objects are rich in water. This led them to conclude that water was likely delivered to Earth via unmelted, or chondritic, meteorites.

Megan Newcombe, Degassing of early-formed planetesimals restricted water delivery to Earth, Nature (2023). DOI: 10.1038/s41586-023-05721-5. www.nature.com/articles/s41586-023-05721-5

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Comment by Dr. Krishna Kumari Challa on March 16, 2023 at 9:21am

Air travel: Turbulence increases as climate change becomes worse

Atmospheric turbulence accounts for 71% of in-flight weather-related injuries, and according to scientists turbulence is only worsening with global warming. While winter is typically the most turbulent season, modeling suggests that by the year 2050, summers will be as turbulent as winters were back in the 1950s.

The paper, "Clear‑air turbulence trends over the North Atlantic in high‑resolution climate models," has been published in the international journal Climate Dynamics.

Clear-air turbulence (CAT) is one of the more dangerous weather-related hazards. It usually develops in cloud-free environments of the upper-level atmosphere; offering no visual clues to pilots and undetectable by onboard radar, these events seemingly come out of nowhere. Prolonged exposure to turbulence will shorten the fatigue life, which is the time the aircraft can be in service. Aircraft fittings can be damaged and severe structural damage can result from more intense clear-air turbulence. In extremely rare cases, this could even lead to the break-up of the aircraft. During moderate turbulence, unrestrained items of cargo, passenger luggage or passengers themselves can collide, causing damage or injury.

The intensity of a jet stream depends on latitudinal horizontal temperature gradients. Due to the steepening of the pole-to-equator temperature gradient in the upper troposphere and lower stratosphere, jet streams are expected to intensify in wind shear with anthropogenic climate change.

The study used three global climate  modeling simulators covering the period 1950–2050 in the formation analysis.

Based on the assessment, for every 1 °C of global near-surface warming, moderate CAT events will increase by 14% in summer and autumn and by 9% for winter and spring. Moderate turbulence is described as inflicting vertical accelerations of up to 0.5g.

With increased turbulence in all seasons, more fights will encounter CAT events on current flight paths. One option for airlines will be to attempt to avoid areas where CAT forms. This might cause longer transatlantic flight times and thousands of additional hours of accumulated flight and fuel costs—a good reminder that the seatbelt sign is there for a reason, and keeping yours on even when the light is off might be the safest plan in the future.

Isabel H. Smith et al, Clear-air turbulence trends over the North Atlantic in high-resolution climate models, Climate Dynamics (2023). DOI: 10.1007/s00382-023-06694-x

Comment by Dr. Krishna Kumari Challa on March 16, 2023 at 9:10am

Comment by Dr. Krishna Kumari Challa on March 15, 2023 at 12:29pm

End the era of eponyms It’s time to axe the practice of naming species after individuals, say 11 ecologists and biologists. They admit that “any call for exceptional changes in how we name nature requires an exceptional rationale”. But they argue that ‘eponyms’ burden the foundation of taxonomy with po... — especially the residue of colonialism. For example, more than 60% of the eponyms given to the flora of New Caledonia are named for French citizens (and 94% of them honour men).

Comment by Dr. Krishna Kumari Challa on March 15, 2023 at 12:17pm

The FDA Just Approved The First Fast-Acting Nasal Spray For Migraines

The US Food and Drug Administration has approved a fast-acting nasal spray from Pfizer designed to treat migraines, the US pharmaceutical giant said Friday.

​Pfizer said it expected the drug, marketed under the name Zavzpret, to be available in pharmacies in July 2023.

​The FDA approval of Zavzpret marks a significant breakthrough for people with migraine who need freedom from pain and prefer alternative options to oral medications.

​A Phase 3 study of the drug found that it delivered pain relief to some migraine sufferers in as little as 15 minutes.

​As a nasal spray with rapid drug absorption, Zavzpret offers an alternative treatment option for people who need pain relief or cannot take oral medications due to nausea or vomiting.

​The treatment for a condition generally tackled with orally taken medicines was double-blind tested on a sample of 1,405 people, with half taking a single spray dose and the remainder receiving a placebo.

​The spray was found to reduce pain significantly when assessed two hours after the onset of a migraine, which as well as causing often severe headaches can include nausea and sensitivity to light or noise.

​Pfizer acquired Zavzpret, also known as Zavegepant, last year for some $10 billion from Biohaven, along with other migraine treatments from the firm.

​source: News agencies

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Comment by Dr. Krishna Kumari Challa on March 14, 2023 at 11:26am

Why do people pull their faces when applying make-up?

This is called 'Mascara Mouth' or 'Mascara face'. Intense focus, raised eyebrows, and a slightly open mouth, combine to create a familiar 'look' when trying to achieve the perfect lash.

‘Mascara face’, as it’s sometimes called, is thought to be a result of nerves in our brains cross-firing. The two nerves controlling our eyeball and eyelid movements are rooted in a very similar part of the brain to another nerve that controls the opening and closing of our jaw. So, it’s possible that when the two nerves in charge of eye movements are activated, they trigger off the nearby mouth-opening nerve.

This is only a theory, though. A simpler explanation is that we’ve learnt that opening our mouths stretches our skin, which helps with applying make-up, so people keep doing it.

Comment by Dr. Krishna Kumari Challa on March 14, 2023 at 11:08am

This process is very different from that in other places. Beijing, for example, is probably the best-studied megacity in the world in terms of its air pollution. However, in the atmosphere of the Chinese capital, particle formation follow different chemical pathways. In China, the gases from emissions such as traffic and wood burning react in the atmosphere during the day when they are exposed to light resulting in the formation of less volatile fumes capable of forming particles during the haze.

Such a pathway was also expected in New Delhi, however the opposite happens. Haze formation from the condensation of directly emitted fumes occurs at night, without photooxidation, driven by increased emissions together with a sharp decrease in temperatures. This work has shown for the first time that semi-volatile gases can form such particles at night, contributing to the haze.

The measurements were carried out in January and February 2019. For this purpose, the researchers from India, Sweden and Switzerland set up a station in the center of New Delhi with measuring equipment that included instruments to determine the number and size of the particles, as well as their chemical composition.

The mass spectrometers deployed are very sensitive and can detect thousands of different molecules in the air of New Delhi, whereby the particle concentrations sometimes reached hundreds of thousands of particles within the volume of air corresponding to a sugar cube. Some of the instruments came from PSI, others from partners such as the Indian Institute of Technology Kanpur and the University of Stockholm.

A second measuring station was also set up in the city with scaled-down equipment to verify that the formation of particulates is indeed a regional phenomenon. Switzerland's contribution was financed by the Swiss Agency for Development and Cooperation.

It took four years of data analysis and peer review before the results were ready to be published in Nature Geoscience.

Suneeti Mishra et al, Rapid night-time nanoparticle growth in Delhi driven by biomass-burning emissions, Nature Geoscience (2023). DOI: 10.1038/s41561-023-01138-x

Part 2

Comment by Dr. Krishna Kumari Challa on March 14, 2023 at 11:06am

Extreme nighttime pollution in New Delhi air explained by new study

In a major joint project with top Indian scientists, PSI researchers have determined why smog forms at night in the Indian capital New Delhi, contrary to all the rules of atmospheric chemistry. Their results have now been published in the journal Nature Geoscience.

For the past three years, New Delhi has been ranked the world's most polluted capital. Its high levels of air pollution are responsible for a large number of premature deaths. In winter, the particulate matter levels exceed 500 micrograms per cubic meter of air. To get some idea of this magnitude, compare this value with the Chinese capital Beijing. In that smog-plagued metropolis, one cubic meter of air contains "only" 70 micrograms of particulates; whereas in Zurich the figure is just 10 micrograms per cubic meter.

Where do these extremely high particulate levels come from in nighttime New Delhi in winter? A team of researchers from the Laboratory for Atmospheric Chemistry at PSI has been investigating this question together with local scientists, including members of the Indian Institute of Technology Kanpur.

They found an extraordinary explanation. "The chemical processes that take place in the air at night are unique to the Indian capital and have not been observed anywhere else in the world.

 In their study, the team found that the trigger for the high levels of particulate matter is the fumes emitted when wood is burnt.

Wood burning is common practice for around 400 million people living in the Indo-Gangetic Plain, who use wood for cooking and heating. In the absence of strict regulations, materials other than wood are also burnt, sometimes including plastic and other waste materials.

Such fires produce a mixture of gases containing countless chemical compounds, such as cresol, which our noses associate with the typical smell of fire, as well as sugar-like molecules from the burnt cellulose in the wood. These molecules cannot be seen in the air with the naked eye, even in high concentrations. However, as night falls the temperature in New Delhi drops so rapidly that some of the gas molecules condense and within a few hours clump together to form particles up to 200 nanometers across, which can be seen as a gray haze.

"Condensation from gas to particulate phase resembles the way in which water droplets form on kitchen surfaces when one is cooking. Particles in the atmosphere act as large surfaces on which gases can condense.

Part 1

Comment by Dr. Krishna Kumari Challa on March 14, 2023 at 8:42am

'Counterportation': Quantum breakthrough paves way for world-first experimental wormhole

One of the first practical applications of the much-hyped but little-used quantum computing technology is now within reach, thanks to a unique approach that sidesteps the major problem of scaling up such prototypes.

The invention, by a  physicist, who gave it the name "counterportation," provides the first-ever practical blueprint for creating in the lab a wormhole that verifiably bridges space, as a probe into the inner workings of the universe.

By deploying a novel computing scheme, revealed in the journal Quantum Science and Technology, which harnesses the basic laws of physics, a small object can be reconstituted across space without any particles crossing. Among other things, it provides a "smoking gun" for the existence of a physical reality underpinning our most accurate description of the world. It provides a theoretical as well as practical framework for exploring afresh enduring puzzles about the universe, such as the true nature of spacetime.

The need for detectable information carriers traveling through when we communicate has been a deeply ingrained assumption among scientists, for instance a stream of photons crossing an optical fiber, or through the air, allowing people to read this text. Or, indeed, the myriad neural signals bouncing around the brain when doing so. This holds true even for quantum teleportation, which, "Star Trek" aside, transfers complete information about a small object, allowing it to be reconstituted elsewhere, so it is indistinguishable in any meaningful way from the original, which disintegrates. The latter ensures a fundamental limit preventing perfect copying. Notably, the recent simulation of a wormhole on Google's Sycamore processor is essentially a teleportation experiment.

Here's the sharp distinction. While counterportation achieves the end goal of teleportation, namely disembodied transport, it remarkably does so without any detectable information carriers traveling across.

The defining task of a traversable wormhole, however, can be neatly abstracted as making space traversable disjunctly; in other words, in the absence of any journey across observable space outside the wormhole.

The pioneering research, fittingly completed to the spine-tingling "Interstellar" score, sets out a way to carry this task out.

If counterportation is to be realized, an entirely new type of quantum computer has to be built: an exchange-free one, where communicating parties exchange no particles.

By contrast to large-scale quantum computers that promise remarkable speed-ups, which no one yet knows how to build, the promise of exchange-free quantum computers of even the smallest scale is to make seemingly impossible tasks—such as counterportation—possible, by incorporating space in a fundamental way alongside time.

The goal in the near future is to physically build such a wormwhole in the lab, which can then be used as a testbed for rival physical theories, even ones of quantum gravity.

Hatim Salih, From counterportation to local wormholes, Quantum Science and Technology (2022). DOI: 10.1088/2058-9565/ac8ecd

Comment by Dr. Krishna Kumari Challa on March 13, 2023 at 12:04pm

What is Plasma?

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