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Comment by Dr. Krishna Kumari Challa on January 8, 2022 at 11:29am

Study explores how bacteria become drug resistant

Researchers  have revealed recently more of the inner-workings of a two-stage "molecular motor" in the cell membrane that enables bacteria to become resistant to drugs.

Their findings, which were reported recently in the journal Nature Chemical Biology, will aid the search for inhibitors that can "turn off" the protein, called an ABC transporter. They also inform efforts to block the human version of the transporter that enables tumor cells to become resistant to chemotherapy.

Understanding how transporters work is essential to developing drugs to block them.

A primary vehicle for resistance is the multi-drug ABC (ATP-binding cassette) exporter. ABC exporters use ATP hydrolysis—the release of chemical energy stored in ATP molecules—to traffic a wide variety of molecules across cell membranes.

ATP energy provides the power for ABC exporters to bind toxic chemicals, then turn around and expel them from the cell. In the case of antibiotic-resistant bacteria, however, this survival tactic can prove deadly to the human host they have invaded.

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Comment by Dr. Krishna Kumari Challa on January 7, 2022 at 12:57pm

“To the limits of our knowledge as humans, we’ve analysed and teste...

Engineer Michael Kaplan, who kicked off the planning of the James Webb Space Telescope in the 1990s, gives insight into how the wildly ambitious project came to be — and what comes next. (The Times of Israel | 19 min read)

Comment by Dr. Krishna Kumari Challa on January 7, 2022 at 12:55pm

Omicron struggles to infect the lungs

Mounting evidence from animal studies suggests that the Omicron coronavirus variant does not multiply readily in lung tissue. This offers a tantalizing explanation for early hints that it causes less-serious disease than does the Delta variant: Omicron might not infect cells deep in the lung as readily as those in the .... Experiments in lung cells and lung organoids suggest that this could be because of a protein called TMPRSS2, which protrudes from the surfaces of many cells in the lungs. Omicron struggles to infect cells through TMPRSS2. Scientists emphasize that Omicron still threatens to overload health systems because of its hyper-transmissibility.

Comment by Dr. Krishna Kumari Challa on January 7, 2022 at 12:52pm

New research shows gene exchange between viruses and hosts drives evolution

The first comprehensive analysis of viral horizontal gene transfer (HGT) illustrates the extent to which viruses pick up genes from their hosts to hone their infection process, while at the same time hosts also co-opt useful viral genes.

HGT is the movement of genetic material between disparate groups of organisms, rather than by the "vertical" transmission of DNA from parent to offspring. Previous studies have looked at HGT between bacteria and their viruses and have shown that it plays a major role in the movement of genes between bacterial species. However a new study, published in Nature Microbiology, looks at interactions between viruses and eukaryotes, which include animals, plants, fungi, protists and most algae.

We knew from individual examples that viral genes have played a role in the evolution of eukaryotes. Even humans have viral genes, which are important for our development and brain function.

Researchers  examined viral-eukaryotic gene transfer in the genomes of hundreds of eukaryotic species and thousands of viruses. They identified many genes that had been transferred and found that HGT from eukaryotes to viruses was twice as frequent as the reverse direction.

In contrast to viruses, eukaryotic organisms retained fewer viral genes, although the ones that were kept appear to have had a major impact on host biology over evolutionary time.

Many of these viral-derived genes appear to have repeatedly affected the structure and form of different organisms, from the cell walls of algae to the tissues of animals. This suggests that host-virus interactions may have played an important role in driving the diversity of life we see today. These transfers not only have evolutionary consequences for both virus and host, but could have important health implications.

HGT allows genes to jump between species including viruses and their hosts. If the gene does something useful, it can sweep through the population and become a feature of that species. This can lead to a rapid emergence of new abilities, as opposed to the more incremental changes that result from smaller mutations.

Although viruses such as Zika and coronaviruses do not appear to participate in these gene transfers, they often manipulate similar genes in their hosts through complex mechanisms. Future research into these transferred genes may therefore provide a novel approach for understanding the infection processes of these and other viruses which could be important for drug discovery.

Nicholas A. T. Irwin, Alexandros A. Pittis, Thomas A. Richards, Patrick J. Keeling. Systematic evaluation of horizontal gene transfer between eukaryotes and viruses. Nature Microbiology, 2021; DOI: 10.1038/s41564-021-01026-3

https://researchnews.cc/news/10930/New-research-shows-gene-exchange...

Comment by Dr. Krishna Kumari Challa on January 6, 2022 at 12:04pm

Magic Acid: Fluorosulfonic acid + Antimony pentafluoride

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...

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