Comment

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?

Comment by Dr. Krishna Kumari Challa on March 13, 2023 at 11:48am

Scientists identify substance that may have sparked life on Earth

A team of scientists dedicated to pinpointing the primordial origins of metabolism—a set of core chemical reactions that first powered life on Earth—has identified part of a protein that could provide scientists clues to detecting planets on the verge of producing life.

The research, published in Science Advances, has important implications in the search for extraterrestrial life because it gives researchers a new clue to look for.

Based on laboratory studies,  scientists say one of the most likely chemical candidates that kickstarted life was a simple peptide with two nickel atoms they are calling "Nickelback" not because it has anything to do with the Canadian rock band, but because its backbone nitrogen atoms bond two critical nickel atoms. A peptide is a constituent of a protein made up of a few elemental building blocks known as amino acids.

Scientists think that sometime between 3.5 and 3.8 billion years ago there was a tipping point, something that kickstarted the change from prebiotic chemistry—molecules before life—to living, biological systems. They think the change was sparked by a few small precursor proteins that performed key steps in an ancient metabolic reaction. And they think they've now found one of these 'pioneer peptides.

When scouring the universe with telescopes and probes for signs of past, present or emerging life, NASA scientists look for specific "biosignatures" known to be harbingers of life. Peptides like nickelback could become the latest biosignature employed by NASA to detect planets on the verge of producing life.

An original instigating chemical, the researchers reasoned, would need to be simple enough to be able to assemble spontaneously in a prebiotic soup. But it would have to be sufficiently chemically active to possess the potential to take energy from the environment to drive a biochemical process.

To do so, the researchers adopted a "reductionist" approach: They started by examining existing contemporary proteins known to be associated with metabolic processes. Knowing the proteins were too complex to have emerged early on, they pared them down to their basic structure.

After sequences of experiments, researchers concluded the best candidate was Nickelback. The peptide is made of 13 amino acids and binds two nickel ions.

Nickel, they reasoned, was an abundant metal in early oceans. When bound to the peptide, the nickel atoms become potent catalysts, attracting additional protons and electrons and producing hydrogen gas. Hydrogen, the researchers reasoned, was also more abundant on early Earth and would have been a critical source of energy to power metabolism.

This work shows that, not only are simple protein metabolic enzymes possible, but that they are very stable and very active—making them a plausible starting point for life.

Jennifer Timm et al, Design of a Minimal di-Nickel Hydrogenase Peptide, Science Advances (2023). DOI: 10.1126/sciadv.abq1990. www.science.org/doi/10.1126/sciadv.abq1990

Comment by Dr. Krishna Kumari Challa on March 13, 2023 at 11:37am

Estrogen receptor in the heart found to regulate obesity in postmenopausal women

Estrogen is known to play an important role in the protection of women's hearts, but once women are postmenopausal and estrogen levels drop, they are at an increased risk of a number of diseases and conditions, including heart disease, obesity and diabetes.

Published in Nature Cardiovascular Research, the study found that reduced ERα in the cells responsible for heart contraction (cardiomyocytes) led to moderate heart dysfunction and increased rates of obesity in female mice, but not in male mice.

Researchers  identified a sex hormone receptor in the heart that can regulate adiposity (obesity) in females. They were interested in trying to understand the role of this estrogen receptor in the heart for some time, to see how it provides protection to the heart.

When they blocked this estrogen receptor, they were expecting to see changes and damage largely to the heart. But rather than seeing a dramatic heart phenotype, what they saw was an adiposity phenotype. So, they observed that the female mice were heavier and had more fat mass, which they  weren't expecting at all.

Genes that are important for contractility of the heart and metabolic function of the heart were also lower in the female heart when ERα was reduced, explaining why the female study hearts did not pump as well.

Extracellular vesicles, that were released from the female hearts with reduced ERα also contained proteins that differed from both the control group and male hearts.

Researchers found that reducing ERα in heart muscle cells (cardiomyocytes) of female mice leads to transcriptional, lipidomic and metabolic dysregulation in the heart, together with metabolic dysregulation in skeletal muscle and adipose tissue. 

Furthermore, the extracellular vesicles that are released from heart cells with reduced ERα had the capacity to reprogram skeletal muscle cells in cell culture. These changes to tissues, the extracellular vesicles proteome and reprogrammed skeletal muscle cells altered the cells' molecular landscape and function. So rather than energy being expended, energy is instead stored, which explains the increased adiposity in female mice in the absence of Erα.

This important work has implications for preventing and treating heart and metabolic disease in post menopausal women, but also cardiotoxicity in premenopausal women receiving therapies that may inhibit or reduce ERα in the heart.

David Greening, Estrogen receptor alpha deficiency in cardiomyocytes reprograms the heart-derived extracellular vesicle proteome and induces obesity in female mice, Nature Cardiovascular Research (2023). DOI: 10.1038/s44161-023-00223-z. www.nature.com/articles/s44161-023-00223-z

Comment by Dr. Krishna Kumari Challa on March 11, 2023 at 2:38pm

In a study last year it was found that virtual-reality train rides seemed to last longer for passengers when the simulated trains were more crowded.

But many prior studies have focused on perception of relatively long time intervals,  and therefore tend to reveal more about how people estimate time than how they experience it directly in the moment.

To shed more light on the latter, the new study looked for links between time perception and bodily rhythms, with a focus on natural fluctuations in heart rate. While the overall cadence of a heart sounds steady, each individual beat can be slightly shorter or longer than the one before.

Research has shown that heartbeats can influence our perception of external stimuli, and the heart has long been suspected of helping the brain keep time.

The heartbeat is a rhythm that our brain is using to give us our sense of time passing.  "And that is not linear – it is constantly contracting and expanding.

While the heart may wield heavy influence on the brain's perception of time, it's a two-way street, the researchers note. Hearing a tone led subjects to focus their attention on the sound, an "orienting response" that in turn changed their heart rate and readjusted their experience of time.

Incorrectly perceiving the passage of time might sound like a bad thing, and sometimes it is. But while losing track of time can lead to trouble, there may also be adaptive benefits to the kind of temporal wrinkles identified in this study.

The heart seems to help the brain work more efficiently with limited resources, the researchers add, influencing how it experiences the passage of time on the smallest scales, and operating at time periods too brief for conscious thoughts or feelings.

"Even at these moment-to-moment intervals, our sense of time is fluctuating" . "A pure influence of the heart, from beat to beat, helps create a sense of time."

https://onlinelibrary.wiley.com/doi/epdf/10.1111/psyp.14270

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part2

Comment by Dr. Krishna Kumari Challa on March 11, 2023 at 2:34pm

Your Heartbeat Shapes Your Perception of Time, Study Finds

Right now, your brain is keeping track of the passage of time without your awareness, letting you focus on better things.

This happens automatically, but not consistently. The brain's perception of time can fluctuate, with some moments seeming to stretch or shrink relative to each objective second.

While these wrinkles in time may be distortions of reality, technically they aren't all in your head. According to a new study, some originate in your heart.

Heartbeats set the pace for time perception.Time is a dimension of the Universe and a core basis for our experience of self. This new research shows that the moment-to-moment experience of time is synchronized with, and changes with, the length of a heartbeat.

These variations in time perception – or "temporal wrinkles" – are normal, researchers say, and may be adaptive. Previous research has also explored their origins, suggesting thoughts and emotions can distort our sense of time, making some moments seem to expand or contract.

part1

Comment by Dr. Krishna Kumari Challa on March 11, 2023 at 1:01pm

Microbes can create a more peaceful world: Scientists issue call to action

Microorganisms should be 'weaponized' to stave off conflicts across the globe, according to a team of eminent microbiologists.

The paper 'Weaponising microbes for peace'  outlines the ways in which microbes and microbial technologies can be used to tackle global and local challenges that could otherwise lead to conflict, but warns that these resources have been severely underexploited to date.

Worldwide deficits and asymmetries in basic resources and services considered to be human rights, such as drinking water, sanitation, healthy nutrition, access to basic healthcare and a clean environment, can lead to competition between peoples for limited resources, tensions, and in some cases conflicts. "There is an urgent need to reduce such deficits, to level up, and to assure provision of basic resources for all peoples. This will also remove some of the causes of conflicts. There is a wide range of powerful microbial technologies that can provide or contribute to this provision of such resources and services, but deployment of such technologies is seriously underexploited.

The paper then lists a series of ways in which microbial technologies can contribute to challenges such as food supply and security, sanitation and hygiene, healthcare, pollution, energy and heating, and mass migrations and overcrowding. For example, microbes are at the core of efforts to tackle pollution by bioremediation, replacing chemical methods of treating drinking water with metalloid conversion systems, and producing biofuels from wastes. "There is now a desperate need for a determined effort by all relevant actors to widely deploy appropriate microbial technologies to reduce key deficits and asymmetries, particularly among the most vulnerable populations.

There is now a desperate need for a determined effort by all relevant actors to widely deploy appropriate microbial technologies to reduce key deficits and asymmetries, particularly among the most vulnerable populations.

Not only will this contribute to the improvement of humanitarian conditions and leveling up, and thereby to a reduction in tensions that may lead to conflicts, but also advance progress towards attainment of Sustainable Development Goals.

"We must weaponise microbes for peace."

The editorial is published in Microbial Biotechnology.

Shailly Anand et al, Weaponising microbes for peace, Microbial Biotechnology (2023). DOI: 10.1111/1751-7915.14224

Comment by Dr. Krishna Kumari Challa on March 11, 2023 at 12:42pm

You're stuck with your same old genome, but corals aren't

Some corals live to be hundreds, and even thousands, of years old. They were born with genes that were successful back in their parent's generation, so how can these old corals still be successful now? Especially in a changing climate? It's possible that the generation and the filtering of mutations that occur in different parts of a big coral act as a proving ground for adaptive genetics for the future. A new study shows a novel way that some very ancient animals might be surviving.

You got your entire set of genes—good or bad—from your parents, and those are the only genes you will have for your entire life. Those genes are also the only ones you will pass along to your children. Of course, there are a few exceptions—like mutations that happen in sperm or egg cells that you might pass along to the next generation. And a growing chorus of technologies is poised to alter harmful mutations in human genes that make life difficult, such as recent success in altering the genes in lung cells that cause cystic fibrosis.

Nearly every animal must make a living with a set of genes that remains virtually unchanged during their lifetime, but a recent study of tropical reef building corals shows something different. These very long-lived animals are constantly changing and testing their genes—and some of these changes make it into the next generation. In this way a centuries-old coral might be a cauldron of genetic innovation, and it might help prepare them for climate change.

Elora H. López-Nandam et al, Mutations in coral soma and sperm imply lifelong stem cell renewal and cell lineage selection, Proceedings of the Royal Society B: Biological Sciences (2023). DOI: 10.1098/rspb.2022.1766

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