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Comment by Dr. Krishna Kumari Challa on October 1, 2024 at 11:08am

Well-designed AI tools can help clean toxic comments up

Imagine scrolling through social media  only to be interrupted by insulting and harassing comments. What if an artificial intelligence (AI) tool stepped in to remove the abuse before you even saw it?

This isn't science fiction. Commercial AI tools like ToxMod and Bodyguard.ai are already used to monitor interactions in real time across social media and gaming platforms. They can detect and respond to toxic behavior.

The idea of an all-seeing AI monitoring our every move might sound Orwellian, but these tools could be key to making the internet a safer place.

However, for AI moderation to succeed, it needs to prioritize values like privacy, transparency, explainability and fairness. So can we ensure AI can be trusted to make our online spaces better? Two recent research projects into AI-driven moderation show this can be done—with more work ahead. 

https://www.ai-ally.org/

https://jigsaw.google.com/harassment-manager/

https://hateandhope.righttobe.org/pages/about-page

https://theconversation.com/online-spaces-are-rife-with-toxicity-we...

Comment by Dr. Krishna Kumari Challa on October 1, 2024 at 11:00am

A cooling system that works on gravity instead of electricity

This device needs no electricity, as it extracts water from the air using nothing more than gravity and relies on cheap, readily available materials.

Along with keeping the solar cells and other semiconductor technologies cool, the water can be repurposed for irrigation, washing, cooling buildings on which the solar cells are placed, and other applications.

Scientists estimate that the atmosphere contains six times more water than all the fresh water in the rivers combined. This water can be collected by atmospheric water harvesting technologies.

While these technologies work reasonably well, in arid environments they require electricity to harvest practical amounts of water. This demand risks deterring the adoption of solar cells in rural regions , where electricity infrastructure is costly.

One reason for the low efficiency is that the water adheres to the surface of the harvesting device.

Researchers found that by adding a lubricant coating that is a mix of a commercial polymer and silicon oil, they could collect more water by relying on only gravity.

The system doesn't consume any electricity, leading to energy savings. Moreover, it doesn't rely on any mechanical parts like compressors or fans, reducing the maintenance over traditional systems, leading to further savings.

Shakeel Ahmad et al, Lubricated Surface in a Vertical Double‐Sided Architecture for Radiative Cooling and Atmospheric Water Harvesting, Advanced Materials (2024). DOI: 10.1002/adma.202404037

Comment by Dr. Krishna Kumari Challa on October 1, 2024 at 10:24am

New mission to create total solar eclipses in space

A  team of researchers  are working on the launch of a spacecraft mission that will allow us to view the sun's atmosphere in more detail than ever before.

The proposed MESOM mission will enable researchers to study the conditions that create solar storms, leading to improvements in forecasts of space weather on Earth. The MESOM spacecraft will fly on a peculiar trajectory enabled by the gravitational attraction of the Earth, the sun and the moon, and will use the shadow of the moon to re-create a total solar eclipse in space once every lunar month lasting almost 50 minutes.

Total solar eclipses seen from Earth are much shorter and only last between 10 seconds and 7.5 minutes, with the annular solar eclipse in the Southern Hemisphere this Wednesday 2 October expected to last around seven minutes. Creating a longer eclipse in space will enable the MESOM team to take high-quality images and measurements of the sun's corona, filling gaps in existing understanding of the physical processes taking place in the solar atmosphere that lead to space weather.

Space weather is not a danger to people or animals on Earth, but solar flares and eruptions from the sun known as coronal mass ejections can cause severe disruption to power grids, satellites and other communication technologies on which modern society depends.

MESOM will offer scientists a unique opportunity to study and understand how the sun creates and controls weather in space.

But MESOM also offers the general public an opportunity to engage with the beauty and spectacle of a total solar eclipse as all their images will be readily available. They aim to reveal the secrets of the sun while inspiring a new generation of space scientists and engineers.

MESOM is an incredibly exciting mission which will advance our scientific understanding of the solar atmosphere and space weather to new levels, enabling us to provide more accurate forecasts and take mitigating action.

By creating eclipses that last up to 48 minutes in space, rather than the maximum 7.5 minutes we manage to see on Earth, we stand a much better chance of unlocking their secrets.

https://www.ucl.ac.uk/news/2024/sep/new-mission-create-total-solar-...

Comment by Dr. Krishna Kumari Challa on October 1, 2024 at 9:26am

Mount Everest is a remarkable mountain of myth and legend and it's still growing. Our research shows that as the nearby river system cuts deeper, the loss of material is causing the mountain to spring further upwards.

Today, the Arun river runs to the east of Mount Everest and merges downstream with the larger Kosi river system. Over millennia, the Arun has carved out a substantial gorge along its banks, washing away billions of tons of earth and sediment.
An interesting river system exists in the Everest region. The upstream Arun river flows east at high altitude with a flat valley. It then abruptly turns south as the Kosi river, dropping in elevation and becoming steeper. This unique topography, indicative of an unsteady state, likely relates to Everest's extreme height.
The uplift is not limited to Mount Everest, and affects neighboring peaks including Lhotse and Makalu, the world's fourth and fifth highest peaks respectively. The isostatic rebound boosts the heights of these peaks by a similar amount as it does Everest, though Makalu, located closest to the Arun river, would experience a slightly higher rate of uplift.
Mount Everest and its neighboring peaks are growing because the isostatic rebound is raising them up faster than erosion is wearing them down. We can see them growing by about two millimeters a year using GPS instruments and now we have a better understanding of what's driving it.
By looking at the erosion rates of the Arun, the Kosi and other rivers in the region, the researchers were able to determine that about 89,000 years ago the Arun river joined and merged with the Kosi river network, a process called drainage piracy.

In doing so, more water was funneled through the Kosi river, increasing its erosive power and taking more of the landscape's soils and sediments with it. With more of the land washed away, it triggered an increased rate of uplift, pushing the mountains' peaks higher and higher.
The interaction between the erosion of the Arun river and the upward pressure of the Earth's mantle gives Mount Everest a boost, pushing it up higher than it would otherwise be.

Jin-Gen Dai, Recent uplift of Chomolungma enhanced by river drainage piracy, Nature Geoscience (2024). DOI: 10.1038/s41561-024-01535-w. www.nature.com/articles/s41561-024-01535-w

Part 2

Comment by Dr. Krishna Kumari Challa on October 1, 2024 at 9:24am

Why is Mount Everest so high? Because a river is pushing up Mount Everest's peak!

Mount Everest is about 15 to 50 meters taller than it would otherwise be because of uplift caused by a nearby eroding river gorge, and continues to grow because of it, finds a new study.

The study, published in Nature Geoscience, found that erosion from a river network about 75 kilometers from Mount Everest is carving away a substantial gorge. The loss of this landmass is causing the mountain to spring upwards by as much as 2 millimeters a year and has already increased its height by between 15 and 50 meters over the past 89,000 years.

At 8,849 meters high Mount Everest  is the tallest mountain on Earth, and rises about 250 meters above the next tallest peak in the Himalayas. Everest is considered anomalously high for the mountain range, as the next three tallest peaks—K2, Kangchenjunga and Lhotse—all only differ by about 120 meters from each other.

A significant portion of this anomaly can be explained by an uplifting force caused by pressure from below Earth's crust after a nearby river eroded away a sizable amount of rocks and soil. It's an effect called isostatic rebound, where a section of the Earth's crust that loses mass flexes and "floats" upwards because the intense pressure of the liquid mantle below is greater than the downward force of gravity after the loss of mass.

It's a gradual process, usually only a few millimeters a year, but over geological timeframes can make a significant difference to the Earth's surface.

The researchers found that, because of this process, Mount Everest has grown by about 15 to 50 meters over the last 89,000 years, since the nearby Arun river merged with the adjacent Kosi river network.

Part 1

Comment by Dr. Krishna Kumari Challa on October 1, 2024 at 9:18am

Researchers witness nanoscale water formation in real time

For the first time ever, researchers have witnessed—in real time and at the molecular-scale—hydrogen and oxygen atoms merge to form tiny, nano-sized bubbles of water.

The event occurred as part of a new  study, during which scientists sought to understand how palladium, a rare metallic element, catalyzes the gaseous reaction to generate water. By witnessing the reaction at the nanoscale, the  team unraveled how the process occurs and even uncovered new strategies to accelerate it.

Because the reaction does not require extreme conditions, the researchers say it could be harnessed as a practical solution for rapidly generating water in arid environments, including on other planets.

The research is published in the Proceedings of the National Academy of Sciences.

Yukun Liu et al, Unraveling the adsorption-limited hydrogen oxidation reaction at palladium surface via in situ electron microscopy, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2408277121

Comment by Dr. Krishna Kumari Challa on October 1, 2024 at 8:33am

Myelin fatty acid metabolism could serve as an energy reserve for the central nervous system

The brains of mammals expend a significant amount of energy in the form of adenosine triphosphate (ATP). This is the molecule that cells use to transfer energy, ultimately fueling several biological processes.

Unlike other organs that have fat cells, neurons and other cells in the central nervous system (CNS) have so far not been known to possess obvious local energy reserves. While astrocytes can use stored glycogen to temporarily protect neurons in the event of low blood sugar levels (i.e., hypoglycemia), a persistent lack of glucose has been found to contribute to neurodegeneration in the long-term.

Researchers   worldwide recently carried out a study investigating the contribution of glial fatty acid metabolism to the storage of energy that can also be used by other cells in the CNS.

Their findings, published in Nature Neuroscience, suggest that the oligodendroglial lipid metabolism can serve as an energy reserve, helping to overcome glucose deprivation and associated neurodegeneration.

Their experiments showed that lack of glucose was surprisingly well tolerated by oligodendrocytes, but only if they could degrade fatty acids from myelin and generate ATP by oxidizing the breakdown products in mitochondria.

When conducting further experiments, the researchers found that the energy generated by oligodendrocytes from lipids could also support the electrical spiking activity of myelinated axons in the optic nerve. Using cell-specific mouse mutants, they showed that oligodendroglial peroxisomes, small organelles found within oligodendrocytes and myelin, also play a role in the turnover of fatty acids.

The findings gathered by them suggest that the myelinated brain of adult mammals could possess a significant reserve of energy that can help to transiently make up for shortages in energy. These findings could have important implications for the study of disorders associated with the loss of brain white matter as a result of starvation, such as anorexia nervosa.

Neurodegenerative diseases that are associated with gradual myelin loss may also reflect this mechanism of metabolizing fatty acids from the myelin sheath.

Ebrahim Asadollahi et al, Oligodendroglial fatty acid metabolism as a central nervous system energy reserve, Nature Neuroscience (2024). DOI: 10.1038/s41593-024-01749-6.

Comment by Dr. Krishna Kumari Challa on September 28, 2024 at 11:38am

Scientists Just Discovered a New Cell

Researchers  have found a whole new type of cell that fills a major hole in our understanding of how the mammal body heals.

For over a century, scientists have hypothesized that a cell like this existed – and now, an adult version has been found at last, hiding in the aorta of grown mice.

The discovery was nine years in the making. Researchers have named the cells 'EndoMac progenitors', and the team is now searching for similar players in the human body.

These cells have an important job, to help grow blood vessels when the body calls for it.

They are activated by injury or poor blood flow, at which point they rapidly expand to aid in healing.

https://www.nature.com/articles/s41467-024-51637-7

Comment by Dr. Krishna Kumari Challa on September 28, 2024 at 11:07am

Can a virus reverse antibiotic resistance?

Bacteriophages — viruses that infect bacteria — are being used alongside antibiotics in a two-pronged attack to treat bacterial infections. Some phages target the ‘efflux pumps’ that bacteria use to expel unwanted molecules from inside their cells. Bacteria treated with phages face a dilemma: if they remove the efflux pumps to evade the phages, then antibiotics will kill them. If they evolve to modify the efflux pumps to expel the antibiotics, the phages will kill them instead. In the lab and in the clinic, researchers are having some success using phages to reverse antibiotic resistance, but it remains very case specific.

https://knowablemagazine.org/content/article/health-disease/2024/ph...

Comment by Dr. Krishna Kumari Challa on September 28, 2024 at 10:31am

One-electron bond 

Scientists have observed a single-electron covalent bond between two carbon atoms for the fi.... Researchers synthesized a molecule with a stable ‘shell’ of fused carbon rings that stretched out a carbon–carbon bond in its centre. The pull makes it susceptible to losing one electron in an oxidation reaction, leaving the elusive one-electron bond. With the new finding, the team hopes to better understand what defines a chemical bond in the first place. “The covalent bond is one of the most important concepts in chemistry,” says chemist Takuya Shimajiri. “At what point does a bond qualify as covalent, and at what point does it not?”

Nature | 5 min read
 Nature paper

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