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Comment by Dr. Krishna Kumari Challa on September 17, 2021 at 9:46am

Part of the universe's missing matter found

Galaxies can receive and exchange matter with their external environment thanks to the galactic winds created by stellar explosions. Via the MUSE instrument from the Very Large Telescope at the ESO, an international research team, led on the French side by the CNRS and l'Université Claude Bernard Lyon 1, has mapped a galactic wind for the first time. This unique observation, which is detailed in a study published in MNRAS on 16 September 2021, helped to reveal where some of the universe's missing matter is located and to observe the formation of a nebula around a galaxy.

Galaxies are like islands of stars in the universe, and possess ordinary, or baryonic, matter, which consists of elements from the periodic table, as well as dark matter, whose composition remains unknown. One of the major problems in understanding the formation of galaxies is that approximately 80% of the baryons that make up the normal matter of galaxies is missing. According to models, they were expelled from galaxies into inter-galactic space by the galactic winds created by stellar explosions.

An international team led on the French side by researchers from the CNRS and l'Université Claude Bernard Lyon successfully used the MUSE instrument to generate a detailed map of the galactic wind driving exchanges between a young galaxy in formation and a nebula (a cloud of gas and interstellar dust).

The perfect positioning of the galaxy and the quasar, as well as the discovery of gas exchange due to galactic winds, made it possible to draw up a unique map. This enabled the first observation of a nebula in formation that is simultaneously emitting and absorbing magnesium—some of the universe's missing baryons—with the Gal1 galaxy.

This type of normal matter nebula is known in the near universe, but their existence for young galaxies in formation had only been supposed.

Scientists thus discovered some of the universe's missing baryons, thereby confirming that 80–90% of normal matter is located outside of galaxies, an observation that will help expand models for the evolution of galaxies.

 Johannes Zabl et al, MusE GAs FLOw and Wind (MEGAFLOW) VIII. Discovery of a Mgii emission halo probed by a quasar sightline, Monthly Notices of the Royal Astronomical Society (2021). DOI: 10.1093/mnras/stab2165

https://phys.org/news/2021-09-universe.html?utm_source=nwletter&...

Comment by Dr. Krishna Kumari Challa on September 17, 2021 at 9:28am

New technology makes it possible to see clearly through murky water

Researchers have developed a new method that can automatically produce clear images through murky water. The new technology could be useful for searching for drowning victims, documenting submerged archaeological artifacts and monitoring underwater farms.

Imaging clearly underwater is extremely challenging because the water and the particles in it tend to scatter light. But, because scattered light is partially polarized, imaging using a camera that is sensitive to polarization can be used to suppress scattered light in underwater images.

A  new method overcomes the limitations of traditional polarimetric underwater imaging, laying the groundwork for taking this method out of the lab and into the field.

Traditional approaches to underwater imaging use either prior knowledge of the imaging area or the background of an image to calculate and remove scattered light. These methods have limited utility in the field because they typically require manual processing, images do not always have visible backgrounds, and prior information is not always available.

To overcome these challenges, the researchers combined a traditional polarized imaging setup with a new algorithm that automatically finds the optimal parameters to suppress the scattering light. This not only significantly improves image contrast to achieve clear imaging but can be used without any prior knowledge of the imaging area and for images with or without background regions.

Hongyuan Wang et al, Automatic underwater polarization imaging without background region or any prior, Optics Express (2021). DOI: 10.1364/OE.434398

https://phys.org/news/2021-09-technology-murky.html?utm_source=nwle...

Comment by Dr. Krishna Kumari Challa on September 17, 2021 at 8:39am

Researchers infuse bacteria with silver to improve power efficiency in fuel cells

A team of engineers and chemists has taken a major step forward in the development of microbial fuel cells—a technology that utilizes natural bacteria to extract electrons from organic matter in wastewater to generate electrical currents. A study detailing the breakthrough was recently published in Science. 

Living energy-recovery systems utilizing bacteria found in wastewater offer a one-two punch for environmental sustainability efforts. The natural populations of bacteria can help decontaminate groundwater by breaking down harmful chemical compounds. Now, research also shows a practical way to harness renewable energy from this process.

The team focused on the bacteria genus Shewanella, which have been widely studied for their energy-generation capabilities. They can grow and thrive in all types of environments—including soil, wastewater and seawater—regardless of oxygen levels.  

Shewanella species naturally break down organic waste matter into smaller molecules, with electrons being a byproduct of the metabolic process. When the bacteria grow as films on electrodes, some of the electrons can be captured, forming a microbial fuel cell that produces electricity. 

However, microbial fuel cells powered by Shewanella oneidensis have previously not captured enough currents from the bacteria to make the technology practical for industrial use. Few electrons could move quickly enough to escape the bacteria's membranes and enter the electrodes to provide sufficient electrical currents and power.

To address this issue, the researchers added nanoparticles of silver to electrodes that are composed of a type of graphene oxide. The nanoparticles release silver ions, which bacteria reduce to silver nanoparticles using electrons generated from their metabolic process and then incorporate into their cells. Once inside the bacteria, the silver particles act as microscopic transmission wires, capturing more electrons produced by the bacteria.

With greatly improved electron transport efficiency, the resulting silver-infused Shewanella film outputs more than 80% of the metabolic electrons to external circuit, generating a power of 0.66 milliwatts per square centimeter—more than double the previous best for microbial-based fuel cells.

Silver nanoparticles boost charge extraction efficiency in Shewanella microbial fuel cells, Science (2021). DOI: 10.1126/science.abf3427

https://phys.org/news/2021-09-infuse-bacteria-silver-power-efficien...

Comment by Dr. Krishna Kumari Challa on September 17, 2021 at 8:30am

Burning space mystery solved as researchers confirm origins of 'empty sky' gamma-rays

Star-forming galaxies are responsible for creating gamma-rays that until now had not been associated with a known origin, researchers have confirmed.

Until now it has been unclear what created gamma-rays—one of the most energetic forms of light in the Universe—that appear in patches of seemingly "empty sky."

The discovery could offer clues to help astronomers solve other mysteries of the Universe, such as what kind of particles make up Dark Matter—one of the holy grails of astrophysics.

"It's a significant milestone to finally discover the origins of this gamma-ray emission, solving a mystery of the Universe astronomers have been trying to decipher since the 1960s.

There are two obvious sources that produce large amounts of gamma-rays seen in the Universe. One when gas falls into the supermassive black holes which are found at the centers of all galaxies—called an active galactic nucleus (AGN)—and the other associated with star formation in the disks of galaxies.

Researchers modeled the gamma-ray emission from all the galaxies in the Universe and compared our results with the predictions for other sources and found that it is star-forming galaxies that produce the majority of this diffuse gamma-ray radiation and not the AGN process.

researchers were able to pinpoint what created these mysterious gamma-rays after obtaining a better understanding of how cosmic rays—particles that travel at speeds very close to the speed of light—move through the gas between the stars. Cosmic rays are important because they create large amounts of gamma-ray emission in star-forming galaxies when they collide with the interstellar gas.

Matt A. Roth et al, The diffuse γ-ray background is dominated by star-forming galaxies, Nature (2021). DOI: 10.1038/s41586-021-03802-x Matt A. Roth et al, The diffuse γ-ray background is dominated by star-forming galaxies, Nature (2021). DOI: 10.1038/s41586-021-03802-x

https://phys.org/news/2021-09-space-mystery-sky-gamma-rays.html?utm...

Comment by Dr. Krishna Kumari Challa on September 16, 2021 at 11:48am

Why Nearly 80 Percent of Autoimmune Sufferers Are Female

The effects of sex hormones, X chromosomes and different gut microbes may be parts of the answer.

Comment by Dr. Krishna Kumari Challa on September 16, 2021 at 11:40am

For The First Time, Scientists Have Entangled Three Qubits on Silicon

Scientists have got three entangled qubits operating together on a single piece of silicon.

It's the first time that's ever been done, and the silicon material is important: that's what the electronics inside today's computers are based on, so it's another advancement in  bridging the gap between the quantum and classical computing realms.

Qubits are the quantum equivalent of the standard bits inside a conventional computer: they can represent several states at once, not just a 1 or a 0, which – in theory – means an exponential increase in computing power.

The real magic happens when these qubits are entangled, or tightly linked together.

As well as increases in computing power, the addition of more qubits means better error correction – a key part of keeping quantum computers stable enough to use them outside of research laboratories.

Two-qubit operation is good enough to perform fundamental logical calculations. But a three-qubit system is the minimum unit for scaling up and implementing error correction.

The process involved entangling two qubits to begin with, in what's known as a two-qubit gate – a standard building block of quantum computers. That gate was then combined with a third qubit with an impressively high fidelity of 88 percent (a measure of how reliable the system is).

Each of the quantum silicon dots holds a single electron, with its spin-up and spin-down states doing the encoding. The setup also included an integrated magnet, enabling each qubit to be controlled separately using a magnetic field.

The researchers think there's plenty more to come from quantum silicon dots linking together more and more qubits in the same circuit. Full-scale quantum computers could be closer than we think.

https://www.nature.com/articles/s41565-021-00925-0

https://www.sciencealert.com/scientists-have-entangled-three-qubits...

Comment by Dr. Krishna Kumari Challa on September 16, 2021 at 11:25am

Ancient marsupial ‘junk DNA’ might be useful after all, scientists say

Comment by Dr. Krishna Kumari Challa on September 16, 2021 at 11:12am

Alzheimer’s disease: hyperbaric oxygen proposed as treatment in new study

Alzheimer’s disease, the most common form of dementia, has long been associated with a build-up of plaques (clumps of protein) in the brain. Scientists in Israel have shown that a type of oxygen therapy can stop new plaques forming and even remove existing plaques in mice with Alzheimer’s.

The scientists used a mouse model of Alzheimer’s disease called 5xFAD. The genetically modified mice were treated with hyperbaric oxygen therapy to see if they could halt or slow the disease progression.

Hyperbaric oxygen therapy involves breathing pure oxygen in a pressurised chamber. In the chamber, the air pressure is increased two to three times higher than normal air pressure. It is commonly used to treat decompression sickness (a condition scuba divers can suffer from), carbon monoxide poisoning, and some forms of stroke or brain injury. It works by forcing increased oxygenation of tissues with low oxygen levels (hypoxia). And it could improve blood flow to the brain to nourish brain cells that are usually deprived of blood, and hence oxygen, in Alzheimer’s disease.

The scientists, from the University of Tel Aviv, treated 15 six-month-old mice (about 30 human years) with hyperbaric oxygen therapy for an hour a day, five days a week for four weeks. The therapy not only reduced the number and size of plaques in the brains of the mice, it also slowed the formation of new plaques, compared with a control group of mice who did not receive hyperbaric oxygen therapy.

Blood flow to the brain is reduced in people with Alzheimer’s. This study showed increased blood flow to the brain in the mice receiving oxygen therapy, which helps with the clearance of plaques from the brain, and reduces inflammation – a hallmark of Alzheimer’s.

By improving blood flow to the brain, reducing plaque levels and reducing hypoxia, the mice undergoing daily oxygen therapy began to show improvements to their cognitive abilities, such as their spatial recognition memory as well as contextual memory – the ability to remember emotional, social, spatial or temporal circumstances related to an event.

The researchers then used these findings to assess the effectiveness of oxygen therapy in six people over the age of 65 with cognitive decline. They found that 60 sessions of oxygen therapy, over 90 days, increased blood flow in certain areas of the brain and significantly improved the patients’ cognitive abilities – improved memory, attention and information processing speed.

Taken together, these findings suggest that oxygen therapy may be able to reduce cognitive decline associated with ageing and dementia in both mice and people.

https://www.aging-us.com/article/203485/text

https://theconversation.com/alzheimers-disease-hyperbaric-oxygen-pr...

Comment by Dr. Krishna Kumari Challa on September 16, 2021 at 10:39am

You will no longer need a password for Microsoft accounts

Microsoft announced in a blog post recently that it will give users the option to access their accounts without using a password.

Users can choose between downloading the Microsoft Authenticator app - a security key a verification code sent to your phone or secondary email address, or Windows Hello, a biometric option that involves scanning your face, iris or fingerprint.

With the Authenticator app, for example, users get notified on their smartphone during a login attempt, and receive a prompt confirming their identity.

The new option tackles two problems: complex passwords people can't remember and passwords that do not offer enough security because they're too simple.

The feature will be rolled out in the coming weeks.

https://www.microsoft.com/insidetrack/blog/no-more-passwords-the-re...

Comment by Dr. Krishna Kumari Challa on September 16, 2021 at 9:50am

Researchers identified a comprehensive network of cell signaling defects in non-diabetic individuals and also uncovered critical nodes of signaling changes shared with type 2 diabetic patients.

These critical nodes where signaling was altered go well beyond the classical insulin signaling, opening a whole new view of insulin resistance. One of the most striking and surprising findings was that many of the signaling changes were sex specific.

Thus, even in the absence of adding sex hormones, these male and female cells showed differences in their phosphoproteome fingerprint. This was very unexpected.

Importantly, the investigators also found that the differences and changes did reflect on multiple downstream biological processes, implying that therapeutic interventions at specific points in the signaling cascade will likely affect biological outcomes.

"Further investigation will be needed to identify the regulators that are responsible for the phosphoproteome changes associated with insulin resistance, and for the drastic differences by sex. "Unraveling these critical nodes in insulin resistance will be able to serve as novel targets for the development of future therapies."

https://medicalxpress.com/news/2021-09-differences-cellular-clues-i...

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