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Comment by Dr. Krishna Kumari Challa on May 30, 2021 at 11:54am

Fight against antibiotic-resistant bacteria has a glowing new weapon

In the perpetual arms races between bacteria and human-made antibiotics, there is a new tool to give human medicine the edge, in part by revealing bacterial weaknesses and potentially by leading to more targeted or new treatments for bacterial infections.

A research team has developed chemical probes to help identify an enzyme, produced by some types of E. coli and pneumococcal bacteria, known to break down several common types of antibiotics, making these bacteria dangerously resistant to treatment.

In response to antibiotic treatment, bacteria have evolved various mechanisms to resist that treatment, and one of those is to make enzymes that basically chew up the antibiotics before they can do their job. The type of tool researchers now developed gives us critical information that could keep us one step ahead of deadly bacteria.

I n a paper published online in the Journal of the American Chemical Society, the researchers zeroed in on the threat posed by the bacterial enzyme called New Delhi metallo-beta-lactamase (NDM). They set out to create a molecule that glows when it comes into contact with the NDM enzyme. When these chemical probes are added to a test tube, they bind to the enzyme and glow. Such a tool could be used to alert doctors to what kind of bacterial threat is affecting their patients and tell them which antibiotics to use.

NDM breaks down antibiotics in the penicillin, cephalosporin and carbapenem classes, which are some of the safest and most effective treatments for bacterial infections. Other classes of antibiotics exist, but they may carry more side effects, have more drug interactions and may be less available in some parts of the world.

In addition to indicating the presence of the NDM enzyme, the florescent chemical probe developed  may help find a different way to combat these resistant bacteria. One treatment option that doctors use with resistant bacteria is to combine common antibiotics and an inhibitor. Although there is no known clinically effective inhibitor for NDM-producing bacteria, this probe could help find one.

Once the probe has bound to the enzyme and begun to glow, if an effective inhibitor is introduced, it will knock the probe loose and the glow would stop. This allows scientists to test a high volume of potential drugs very quickly.

1. Radhika Mehta, Dann D. Rivera, David J. Reilley, Dominique Tan, Pei W. Thomas, Abigail Hinojosa, Alesha C. Stewart, Zishuo Cheng, Caitlyn A. Thomas, Michael W. Crowder, Anastassia N. Alexandrova, Walter Fast, Emily L. Que. Visualizing the Dynamic Metalation State of New Delhi Metallo-β-lactamase-1 in Bacteria Using a Reversible Fluorescent Probe. Journal of the American Chemical Society, 2021; DOI: 10.1021/jacs.1c00290

Comment by Dr. Krishna Kumari Challa on May 29, 2021 at 11:30am

References

1. 1.

   Cabanac, G. & Labbé, C. J. Assoc. Inf. Sci. Technol. https://doi.org/10.1002/asi.24495 (2021).

   Article Google Scholar 

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   Labbé, C. & Labbé, D. Scientometrics 94, 379–396 (2013)

   Article Google Scholar 

https://www.nature.com/articles/d41586-021-01436-7?utm_source=Natur...

Comment by Dr. Krishna Kumari Challa on May 29, 2021 at 11:29am

Hundreds of gibberish papers still lurk in the scientific literature

The nonsensical computer-generated articles, spotted years after the problem was first seen, could lead to a wave of retractions.

Nonsensical research papers generated by a computer program are still popping up in the scientific literature many years after the problem was first seen, a study has revealed¹. Some publishers have told Nature they will take down the papers, which could result in more than 200 retractions.

The issue began in 2005, when three PhD students created paper-generating software called SCIgen for “maximum amusement”, and to show that some conferences would accept meaningless papers. The program cobbles together words to generate research articles with random titles, text and charts, easily spotted as gibberish by a human reader. It is free to download, and anyone can use it.

By 2012, computer scientist Cyril Labbé had found 85 fake SCIgen papers in conferences published by the Institute of Electrical and Electronic Engineers (IEEE); he went on to find more than 120 fake SCIgen papers published by the IEEE and by Springer². It was unclear who had generated the papers or why. The articles were subsequently retracted — or sometimes deleted — and Labbé released a website allowing anyone to upload a manuscript and check whether it seems to be a SCIgen invention. Springer also sponsored a PhD project to help spot SCIgen papers, which resulted in free software called SciDetect. 

References above: 

Comment by Dr. Krishna Kumari Challa on May 29, 2021 at 8:54am

Researchers show how air pollution may contribute to loss of smell

The loss of smell, a condition known as anosmia, can severely impact a person's quality of life, making it extremely difficult to taste foods, detect airborne hazards in the environment and carry out other functions dependent on the sense. Those with anosmia may experience weight concerns, decreased social interaction, depression and general anxiety. In some cases, loss of smell has been linked to death in older adults. Now researchers have studied one of the known causes of anosmia—long-term exposure to air pollution—to better understand how it can rob someone of the ability to smell and taste.

According to the U.S. Environmental Protection Agency (EPA), PM2.5 (the PM stands for "particulate matter") is the term for a mixture of solid particles and liquid droplets found in the air. Depending on location, PM2.5 can consist of many materials, including dust, dirt, soot, smoke, organic compounds and metals. It has been linked to cardiovascular disease, lung cancer, decline in cognitive thinking ability, chronic obstructive pulmonary disease, asthma and premature death. Previous research has associated PM2.5 as a likely culprit in loss of smell.

The researchers found long-term airborne exposure to PM2.5 increases the risk of losing one's smell by nearly twice (a 1.6- to 1.7-fold increase). They think this may occur because the location of the olfactory nerve—which contains the sensory nerve fibers relating to the sense of smell—places it directly in the path of inhaled PM2.5 materials.

Based on this result, the researchers  that long-term exposure to high levels of PM2.5 represents a common risk factor for the loss of sense of smell, especially in vulnerable populations such as older people—but also one that is potentially modifiable if sources of PM2.5 components can be better controlled.

Zhenyu Zhang et al, Exposure to Particulate Matter Air Pollution and Anosmia, JAMA Network Open (2021). DOI: 10.1001/jamanetworkopen.2021.11606

https://medicalxpress.com/news/2021-05-air-pollution-contribute-los...

Comment by Dr. Krishna Kumari Challa on May 28, 2021 at 1:43pm

Physicists Have Broken The Speed of Light With Pulses Inside Hot Plasma

Physicists have been playing hard and fast with the speed limit of light pulses for a while, speeding them up and even slowing them to a virtual stand-still using various materials like cold atomic gases, refractive crystals, and optical fibers.

This time, researchers from Lawrence Livermore National Laboratory in California and the University of Rochester in New York have managed it inside hot swarms of charged particles, fine-tuning the speed of light waves within plasma to anywhere from around one-tenth of light's usual vacuum speed to more than 30 percent faster.

This is both more – and less – impressive than it sounds.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.126.205001

https://www.newscientist.com/article/2278564-laser-pulses-travel-fa...

Comment by Dr. Krishna Kumari Challa on May 28, 2021 at 1:22pm

Bees Opening a Soda Bottle

'Unbelievable' Video Shows Two Bees Work Together to Unscrew a Soda...

Bees Opening a Soda Bottle

Two Bees Work Together to Unscrew a Soda Bottle

Comment by Dr. Krishna Kumari Challa on May 28, 2021 at 1:11pm

Brain Computer Interface Turns Mental Handwriting into Text on Screen

Researchers have, for the first time, decoded the neural signals associated with writing letters, then displayed typed versions of those letters in real time. They hope their invention could one day help people with paralysis communicate.

Comment by Dr. Krishna Kumari Challa on May 28, 2021 at 12:47pm

Had COVID? You’ll probably make antibodies for a lifetime

People who recover from mild COVID-19 have bone-marrow cells that can churn out antibodies for decades, though viral variants could dampen some of the protection they offer.

Many people who have been infected with SARS-CoV-2 will probably make antibodies against the virus for most of their lives. So suggest researchers who have identified long-lived antibody-producing cells in the bone marrow of people who have recovered from COVID-19.

The study provides evidence that immunity triggered by SARS-CoV-2 infection will be extraordinarily long-lasting. Adding to the good news, the implications are that vaccines will have the same durable effect.

team tracked antibody production in 77 people who recovered from mostly mild cases of COVID-19. As expected, SARS-CoV-2 antibodies plummeted in the four months after infection. But this decline slowed, and up to eleven months after infection, the researchers could still detect antibodies that recognized the SARS-CoV-2 spike protein.

Turner, J. S. et al. Nature https://doi.org/10.1038/s41586-021-03647-4 (2021).

Comment by Dr. Krishna Kumari Challa on May 28, 2021 at 11:58am

part 2

So the researchers tried something unorthodox: they rapidly inverted the spin of one of the two atoms with a sudden burst of electric current. To their surprise, this drastic approach resulted in a beautiful quantum interaction, exactly by the book. During the pulse, electrons collide with the atom, causing its spin to rotate.

The electron inverts the spin of one atom causing it to point, say, to the left. You could view this as a measurement, erasing all quantum memory. But from the point of view of the combined system comprising both atoms, the resulting situation is not so mundane at all. For the two atoms together, the new state constitutes a perfect superposition, enabling the exchange of information between them. Crucially for this to happen is that both spins become entangled: a peculiar quantum state in which they share more information about each other than classically possible."

The discovery can be of importance to research on quantum bits. Perhaps also in that research you could get away with being slightly less careful when initializing quantum states. 

"Free coherent evolution of a coupled atomic spin system initialized by electron scattering" Science (2021). science.sciencemag.org/cgi/doi … 1126/science.abg8223

https://phys.org/news/2021-05-scientists-atoms-chatting.html?utm_so...

Comment by Dr. Krishna Kumari Challa on May 28, 2021 at 11:56am

Scientists overhear two atoms chatting

How materials behave depends on the interactions between countless atoms. You could see this as a giant group chat in which atoms are continuously exchanging quantum information. Researchers  have now been able to intercept a chat between two atoms. They present their findings in Science on 28 May.

Atoms, of course, don't really talk. But they can react to each other. This is particularly the case for magnetic atoms. "Each atom carries a small magnetic moment called spin. These spins influence each other, like compass needles do when you bring them close together. If you give one of them a push, they will start moving together in a very specific way.

But according to the laws of quantum mechanics, each spin can be simultaneously point in various directions, forming a superposition. This means that actual transfer of quantum information takes place between the atoms, like some sort of conversation.

On a large scale, this kind of exchange of information between atoms can lead to fascinating phenomena. A classic example is superconductivity: the effect where some materials lose all electrical resistivity below a critical temperature. While well understood for the simplest cases, nobody knows exactly how this effect comes about in many complex materials. But it's certain that magnetic quantum interactions play a key role. For the purpose of trying to explaining phenomena like this, scientists are very interested in being able to intercept these exchanges; to overhear the conversations between atoms.

Scientists  literally put two atoms next to each other to see what happens. This is possible by virtue of a scanning tunneling microscope: a device in which a sharp needle can probe atoms one-by-one and can even rearrange them. The researchers used this device to place two titanium atoms at a distance of just over one nanometer—one millionth of a millimeter—apart. At that distance, the atoms are just able to detect each other's spin. If you would now twist one of the two spins, the conversation would start by itself.

Usually, this twist is performed by sending very precise radio signals to the atoms. This so-called spin resonance technique—which is quite reminiscent of the working principle of an MRI scanner found in hospitals—is used successfully in research on quantum bits. You have barely started twisting the one spin before the other starts to rotate along. This way you can never investigate what happens upon placing the two spins in opposite directions

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