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Comment by Dr. Krishna Kumari Challa on January 6, 2022 at 11:23am

Matter and antimatter seem to respond equally to gravity

New Research has found that within the uncertainty of the experiment, matter and antimatter respond to gravity in the same way.

Matter and antimatter create some of the most interesting problems in physics today. They are essentially equivalent, except that where a particle has a positive charge its antiparticle has a negative one. In other respects they seem equivalent. However, one of the great mysteries of physics today, known as "baryon asymmetry," is that, despite the fact that they seem equivalent, the universe seems made up entirely of matter, with very little antimatter. Naturally, scientists around the world are trying hard to find something different between the two, which could explain why we exist.

As part of this quest, scientists have explored whether matter and antimatter interact similarly with gravity, or whether antimatter would experience gravity in a different way than matter, which would violate Einstein's weak equivalence principle. Now, the new work has shown, within strict boundaries, that antimatter does in fact respond to gravity in the same way as matter.

To make the measurements, the team confined antiprotons and negatively charged hydrogen ions, which they used as a proxy for protons, in a Penning trap. In this device, a particle follows a cyclical trajectory with a frequency, close to the cyclotron frequency, that scales with the trap's magnetic-field strength and the particle's charge-to-mass ratio. By feeding antiprotons and negatively charged hydrogen ions into the trap, one at a time, they were able to measure, under identical conditions, the cyclotron frequencies of the two particle types, comparing their charge-to-mass ratios.

By doing this, researchers were able to obtain a result that they are essentially equivalent, to a degree four times more precise than previous measures. To this level of CPT invariance, causality and locality hold in the relativistic quantum field theories of the Standard Model.

Stefan Ulmer, A 16-parts-per-trillion measurement of the antiproton-to-proton charge–mass ratio, Nature (2022). DOI: 10.1038/s41586-021-04203-w

https://phys.org/news/2022-01-antimatter-equally-gravity.html?utm_s...

Comment by Dr. Krishna Kumari Challa on January 6, 2022 at 11:18am

Physicists watch as ultracold atoms form a crystal of quantum tornadoes

The world we experience is governed by classical physics. How we move, where we are, and how fast we're going are all determined by the classical assumption that we can only exist in one place at any one moment in time.

But in the quantum world, the behavior of individual atoms is governed by the eerie principle that a particle's location is a probability. An atom, for instance, has a certain chance of being in one location and another chance of being at another location, at the same exact time.

When particles interact, purely as a consequence of these quantum effects, a host of odd phenomena should ensue. But observing such purely quantum mechanical behavior of interacting particles amid the overwhelming noise of the classical world is a tricky undertaking.

Now, MIT physicists have directly observed the interplay of interactions and quantum mechanics in a particular state of matter: a spinning fluid of ultracold atoms. Researchers have predicted that, in a rotating fluid, interactions will dominate and drive the particles to exhibit exotic, never-before-seen behaviors.

In a study published today in Nature, the MIT team has rapidly rotated a quantum fluid of ultracold atoms. They watched as the initially round cloud of atoms first deformed into a thin, needle-like structure. Then, at the point when classical effects should be suppressed, leaving solely interactions and quantum laws to dominate the atoms' behavior, the needle spontaneously broke into a crystalline pattern, resembling a string of miniature, quantum tornadoes.

This crystallization is driven purely by interactions, and tells us we're going from the classical world to the quantum world.

Martin Zwierlein, Crystallization of bosonic quantum Hall states in a rotating quantum gas, Nature (2022). DOI: 10.1038/s41586-021-04170-2. www.nature.com/articles/s41586-021-04170-2

Richard J. Fletcher et al, Geometric squeezing into the lowest Landau level, Science (2021). DOI: 10.1126/science.aba7202

https://phys.org/news/2022-01-physicists-ultracold-atoms-crystal-qu...

Comment by Dr. Krishna Kumari Challa on January 6, 2022 at 11:02am

3D digital holograms on smartphones

3D holograms, previously seen only in science fiction movies, may soon make their way to consumer technology. Until now, 3D holograms based on phase shifting holography method could be captured using a large, specialized camera with a polarizing filter. However, a  research group has just developed technology that can acquire holograms on mobile devices, such as smartphones.

A research team  was successful in developing a photodiode that detects the polarization of light in the near-infrared region without additional polarization filters and thus, the realization of a miniaturized holographic image sensor for 3D digital holograms, using the 2D semiconductor materials: rhenium diselenide and tungsten diselenide.

Photodiodes, which convert light into current signals, are essential components within the pixels of image sensors in digital and smartphone cameras. Introducing the ability to sense the polarization of light to the image sensor of an ordinary camera provides a variety of new information, enabling the storage of 3D holograms.

Jongtae Ahn et al, Near-Infrared Self-Powered Linearly Polarized Photodetection and Digital Incoherent Holography Using WSe2/ReSe2 van der Waals Heterostructure, ACS Nano (2021). DOI: 10.1021/acsnano.1c06234

https://phys.org/news/2022-01-3d-digital-holograms-smartphones.html...

Comment by Dr. Krishna Kumari Challa on January 6, 2022 at 10:46am

Nearly 2 million children worldwide develop asthma as a result of breathing in traffic-related pollution

Nearly 2 million new cases of pediatric asthma every year may be caused by a traffic-related air pollutant, a problem particularly important in big cities around the world, according to a new study published recently. The study is the first to estimate the burden of pediatric asthma cases caused by this pollutant in more than 13,000 cities from Los Angeles to Mumbai.

The study found that nitrogen dioxide puts children at risk of developing asthma and the problem is especially acute in urban areas. The findings suggest that clean air must be a critical part of strategies aimed at keeping children healthy.

Here are some key findings from the study:

• Out of the estimated 1.85 million new pediatric asthma cases attributed to NO₂ globally in 2019, two-thirds occurred in urban areas.
• The fraction of pediatric asthma cases linked to NO₂ in urban areas dropped recently, probably due to tougher clean air regulations put in place by higher income countries like the United States.
• Despite the improvements in air quality in Europe and the U.S., dirty air, and particularly NO₂ pollution, has been rising in South Asia, Sub-Saharan African and the Middle East.
• Pediatric asthma cases linked to NO₂ pollution represent a large public health burden for South Asia and Sub-Saharan Africa.

https://blogs.gwu.edu/sanenberg/pm2-5-no2-and-ozone-data-for-13000-...

 "Global urban temporal trends in fine particulate matter and attributable health burdens: estimates from global datasets," Lancet Planetary Health, DOI: 10.1016/S2542-5196(21)00350-8 , www.thelancet.com/journals/lan … (21)00350-8/fulltext

"Long-term trends in urban NO2 concentrations and associated pediatric asthma incidence: estimates from global databases,", Lancet Planetary Health, DOI: 10.1016/S2542-5196(21)00255-2 , www.thelancet.com/journals/lan … (21)00255-2/fulltext

https://medicalxpress.com/news/2022-01-million-children-worldwide-a...

Comment by Dr. Krishna Kumari Challa on January 5, 2022 at 12:23pm

French Scientists Discover New Coronavirus Variant

As the world continues to struggle with the rapid spread of the omicron variant of the coronavirus and the still-lingering delta variant, scientists in France say they have discovered a new variant that contains multiple mutations.

Experts at the IHU Mediterranee Infection in Marseille said they had discovered the new variant in December in 12 patients living near Marseille, with the first patient testing positive after traveling to the central African nation of Cameroon.

The French scientists said they had identified 46 mutations in the new variant, dubbed B.1.640.2, that could make it more resistant to vaccines and more infectious than the original virus.

The results were posted on the online health sciences outlet MedRxiv, which publishes studies that have not been peer-reviewed or published in an academic journal. B.1.640.2 has neither been detected in other countries nor been labeled a "variant of concern" by the World Health Organization.

https://www.voanews.com/a/french-scientists-discover-new-coronaviru...

Comment by Dr. Krishna Kumari Challa on January 5, 2022 at 12:18pm

Designing war planes

Comment by Dr. Krishna Kumari Challa on January 5, 2022 at 12:12pm

Ecological coating for fruits and vegetables

Plastic packaging in grocery stores protects fruits and vegetables from spoilage, but also creates significant amounts of waste. Researchers have now developed a protective cover for fruit and vegetables based on renewable raw materials. For this project, they used cellulose.  They spent more than a year developing a special protective cellulose coating that can be applied to fruits and vegetables. The result: Coated fruits and vegetables stay fresh significantly longer. In tests, the shelf life of, for instance, bananas was extended by more than a week. This significantly reduces food waste. 

https://www.youtube.com/watch?v=JT77fj1eF3E&t=62s

https://www.youtube.com/watch?v=9-5YZ2cNSEo

Luana Amoroso et al, Sustainable Cellulose Nanofiber Films from Carrot Pomace as Sprayable Coatings for Food Packaging Applications, ACS Sustainable Chemistry & Engineering (2021). DOI: 10.1021/acssuschemeng.1c06345

https://phys.org/news/2022-01-ecological-coating-bananas.html?utm_s...

Comment by Dr. Krishna Kumari Challa on January 5, 2022 at 9:33am

When we eat, energy-rich fats and glucose enter the bloodstream. Insulin normally shuttles these nutrients to cells in muscles and fat tissue, where they are either used immediately or stored for later use. In people with insulin resistance, glucose is not efficiently removed from the blood, and higher lipolysis increases the fatty acid levels. These extra fatty acids accelerate glucose production from the liver, compounding the already high glucose levels. Moreover, fatty acids accumulate in organs, exacerbating the insulin resistance—characteristics of diabetes and obesity.

Previously, the lab showed that injecting FGF1 dramatically lowered blood glucose in mice and that chronic FGF1 treatment relieved insulin resistance. But how it worked remained a mystery.

In the current work, the team investigated the mechanisms behind these phenomena and how they were linked. First, they showed that FGF1 suppresses lipolysis, as insulin does. Then they showed that FGF1 regulates the production of glucose in the liver, as insulin does. These similarities led the group to wonder if FGF1 and insulin use the same signaling (communication) pathways to regulate blood glucose.

It was already known that insulin suppresses lipolysis through PDE3B, an enzyme that initiates a signaling pathway, so the team tested a full array of similar enzymes, with PDE3B at the top of their list. They were surprised to find that FGF1 uses a different pathway—PDE4.

"This mechanism is basically a second loop, with all the advantages of a parallel pathway. In insulin resistance, insulin signaling is impaired. However, with a different signaling cascade, if one is not working, the other can. That way you still have the control of lipolysis and blood glucose regulation.

Finding the PDE4 pathway opens new opportunities for drug discovery and basic research focused on high blood glucose (hyperglycemia) and insulin resistance. The scientists are eager to investigate the possibility of modifying FGF1 to improve PDE4 activity. Another route is targeting multiple points in the signaling pathway before PDE4 is activated.

The unique ability of FGF1 to induce sustained glucose lowering in insulin-resistant diabetic mice is a promising therapeutic route for diabetic patients.

 Ronald M Evans, FGF1 and insulin control lipolysis by convergent pathways, Cell Metabolism (2022). DOI: 10.1016/j.cmet.2021.12.004. www.cell.com/cell-metabolism/f … 1550-4131(21)00623-9

https://medicalxpress.com/news/2022-01-route-blood-sugar-independen...

Comment by Dr. Krishna Kumari Challa on January 5, 2022 at 9:32am

Researchers find a new route for regulating blood sugar levels independent of insulin

The discovery of insulin 100 years ago opened a door that would lead to life and hope for millions of people with diabetes. Ever since then, insulin, produced in the pancreas, has been considered the primary means of treating conditions characterized by high blood sugar (glucose), such as diabetes. Now, scientists have discovered a second molecule, produced in fat tissue, that, like insulin, also potently and rapidly regulates blood glucose. Their finding could lead to the development of new therapies for treating diabetes, and also lays the foundation for promising new avenues in metabolism research.

The study, which was published in Cell Metabolism on January 4, 2022, shows that a hormone called FGF1 regulates blood glucose by inhibiting fat breakdown (lipolysis). Like insulin, FGF1 controls blood glucose by inhibiting lipolysis, but the two hormones do so in different ways. Importantly, this difference could enable FGF1 to be used to safely and successfully lower blood glucose in people who suffer from insulin resistance.

Finding a second hormone that suppresses lipolysis and lowers glucose is a scientific breakthrough. Scientists have identified a new player in regulating fat lipolysis that will help us understand how energy stores are managed in the body.

Part 1

Comment by Dr. Krishna Kumari Challa on January 4, 2022 at 12:18pm

Scientists reveal the genetic basis of mitochondrial diseases

Mutations in genes encoding mitochondrial aminoacyl-tRNA synthetases are linked to diverse diseases. However, the precise mechanisms by which these mutations affect mitochondrial function and disease development are not fully understood.

Wenlu Fan et al, FARS2 deficiency in Drosophila reveals the developmental delay and seizure manifested by aberrant mitochondrial tRNA metabolism, Nucleic Acids Research (2021). DOI: 10.1093/nar/gkab1187

https://phys.org/news/2022-01-scientists-reveal-genetic-basis-mitoc...

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