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Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 9:17am

Researchers find a simple way to harvest more 'blue energy' from waves

Waves pack a powerful punch. Now, we are one step closer to capturing the energy behind the ocean's constant ebb and flow with an improved "blue energy" harvesting device.

Researchers report in ACS Energy Letters that simply repositioning the electrode—from the center of a see-sawing liquid-filled tube to the end where the water crashes with the most force—dramatically increased the amount of wave energy that could be harvested.

The tube-shaped wave-energy harvesting device improved upon by the researchers is called a liquid–solid triboelectric nanogenerator (TENG). The TENG converts mechanical energy into electricity as water sloshes back and forth against the inside of the tube. One reason these devices aren't yet practical for large-scale applications is their low energy output.

aimed to increase a liquid–solid TENG's energy harvesting ability by optimizing the location of the energy-collecting electrode.

The researchers used 16-inch clear plastic tubes to create two TENGs. Inside the first device, they placed a copper foil electrode at the center of the tube—the usual location in conventional liquid–solid TENGs.

For the new design, they inserted a copper foil electrode at one end of the tube. The researchers then filled the tubes a quarter of the way with water and sealed the ends. A wire connected the electrodes to an external circuit.

Placing both devices on a benchtop, the rocker moved water back and forth within the tubes and generated electrical currents by converting mechanical energy—the friction from water hitting or sliding against the electrodes—into electricity. Compared to the conventional design, the researchers found that the optimized design increased the device's conversion of mechanical energy to electrical current by 2.4 times.

In another experiment, the optimized TENG blinked an array of 35 LEDs on and off as water entered the section of the tube covered by the electrode and then flowed away, respectively.

The researchers say these demonstrations lay the foundation for larger scale blue-energy harvesting from ocean waves and show their device's potential for other applications like wireless underwater signaling communications.

Space Volume Effect in Tube Liquid–Solid Triboelectric Nanogenerator for Output Performance Enhancement, ACS Energy Letters (2024). DOI: 10.1021/acsenergylett.4c00072. pubs.acs.org/doi/abs/10.1021/acsenergylett.4c00072

Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 8:52am

Our own galaxy, the Milky Way, still has a thin star forming disk, so is still considered a high spin rotational galaxy.

"But when we look at the Milky Way in detail, we do see something called the Milky Way thick disk. It's not dominant, in terms of light, but it is there and those look to be older stars, which may well have been heated from the thin disk at earlier times, or born with more turbulent motion in the early universe.

Scott Croom et al, The SAMI Galaxy Survey: galaxy spin is more strongly correlated with stellar population age than mass or environment, Monthly Notices of the Royal Astronomical Society (2024). DOI: 10.1093/mnras/stae458. academic.oup.com/mnras/article … 0.1093/mnras/stae458

Part 2

Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 8:51am

Study reports that age is the driving force in changing how stars move within galaxies

Galaxies start life with their stars rotating in an orderly pattern but in some the motion of stars is more random. Until now, scientists have been uncertain about what causes this—possibly the surrounding environment or the mass of the galaxy itself.

A new study, published in MNRAS (Monthly Notices of the Royal Astronomical Society), has found that the most important factor is neither of these things. It shows the tendency of the stars to have random motion is driven mostly by the age of the galaxy—things just get messy over time.

When researchers did the analysis, they found that age, consistently, whichever way we slice or dice it, is always the most important parameter.

Once you account for age, there is essentially no environmental trend, and it's similar for mass.

"If you find a young galaxy it will be rotating, whatever environment it is in, and if you find an old galaxy, it will have more random orbits, whether it's in a dense environment or a void.

Young galaxies are star-forming super-factories, while in older ones, star formation ceases.

We do know that age is affected by environment. If a galaxy falls into a dense environment, it will tend to shut down the star formation. So galaxies in denser environments are, on average, older.

The point of their analysis is that it's not living in dense environments that reduces their spin, it's the fact that they're older.

Part 1

Comment by Dr. Krishna Kumari Challa on April 3, 2024 at 11:30am

Current estimates suggest that fewer than 100 cases have been reported globally. This underscores its status as one of the rarest form of hives.

Managing this allergy presents a formidable challenge for patients and healthcare providers alike.

Conventional allergy treatments (antihistamines, corticosteroids) offer temporary relief but may not address the underlying cause.

Experimental therapies such as phototherapy (exposing the skin to ultraviolet light) aim to calm the immune response and reduce inflammation. This therapy has shown some promise in alleviating symptoms.

Biologic agents, so-called "large-molecule drugs" made from proteins, target specific immune pathways implicated in allergic reactions. They offer a more targeted therapeutic approach that holds potential for long-term symptom management.

Avoiding water is tricky and involves careful planning, including alternative ways to stay clean.
Using protective barriers, such as emollient creams, can help create a layer between the skin and water, which may help reduce symptom severity and frequency.
investigation into immune system mechanisms underlying aquagenic urticaria is essential to finding new treatments.

Continued clinical trials and studies are crucial to evaluate the efficacy and safety of emerging therapies, such as phototherapy and biologic agents, in managing aquagenic urticaria. Unfortunately, these studies are limited by patient numbers.

https://theconversation.com/water-allergy-a-debilitating-but-thankf...

Part 2

Comment by Dr. Krishna Kumari Challa on April 3, 2024 at 11:28am

Aquagenic Urticaria - commonly known as "water allergy".

Aquagenic urticaria, which has only ever been reported approximately 100 times, causes hives to form when a person's skin comes into contact with water, such as in the shower and pool - and sometimes even from a person's own sweat. 

The first documented mention of water allergy dates to the late 20th century, with case reports detailing the perplexing experiences of people afflicted by water-induced hives.

Since then, sporadic cases have dotted medical literature, contributing to our evolving understanding of this ailment. Recent trends suggest a gradual increase in cases, driven by heightened awareness among healthcare professionals and improved diagnostic capabilities.

This rare affliction transforms the seemingly innocuous act of water contact into a tormenting ordeal, afflicting people such as 22-year-old Loren Montefusco from South Carolina, US.

At its core, water allergy is believed to arise from an abnormal immune response triggered by water's interaction with the skin. Think of your immune system as a vigilant guardian, always on alert for invaders. In aquagenic urticaria, water somehow triggers an alarm response. This leads to the release of substances like histamine – causing hives, welts and itching.

Researchers have pinpointed mutations in specific genes associated with water allergy, such as the FABP5 gene, crucial for skin barrier function. Mutations in this gene disrupt the skin's ability to repel water, activating an inflammatory response.

Variations in genes involved in immune regulation and skin integrity also contribute to susceptibility. However, environmental factors such as hormonal changes or chemical exposure can influence its severity.

Understanding the genetic basis offers insights into how the disease occurs and potential therapies. By identifying specific genetic markers, personalised treatment approaches targeting underlying mechanisms can be developed.

Part 1

Comment by Dr. Krishna Kumari Challa on April 3, 2024 at 9:57am

Hair from tiger thought to be extinct found by conservationist on Java

This is good news for Tiger lovers

 

A team of environmentalists and zoologists affiliated with several institutions in Indonesia has confirmed that a tiger species once thought extinct is still living on the island of Java. In their study, published in the journal Oryx, the group conducted a DNA analysis of a hair found by a conservationist on a plantation on the island. Prior research has shown that the Java tiger once flourished on the island. The tiger is a subspecies of the more well-known Sumatran tiger. But as humans encroached on their territory, leaving little land for the tigers, their numbers began dwindling. After farmers began shooting them for killing livestock, they disappeared completely. In 2008, the species was declared extinct. In this new effort, the research team has found evidence that the declaration may have been premature. Over the past several decades, there have been reports by nonscientists of tigers still living on the island; some even suggested that livestock had been killed by one or more of them. But the sightings were unconfirmed. Then, five years ago, a conservationist working on the island saw what he believed to be a Java tiger on a western part of the island near a plantation. He reported this to a researcher on the island who visited the site and found footprints and claw marks on shrubbery and also a single hair stuck to a fence. A later in-depth interview with the conservationist led the researchers to believe the hair was indeed from a Java tiger. They tested it genetically and compared the results with samples from a museum specimen of a Javan tiger collected in 1930, which showed them to be closely matched. Based on the genetic evidence, the researchers concluded that the hair had come from a Java tiger. The finding shows that the tiger did not go extinct when thought and members of its species had been living on the island, but whether Javan tigers are still there needs to be confirmed with further genetic and field studies.

Wirdateti Wirdateti et al, Is the Javan tiger Panthera tigris sondaica extant? DNA analysis of a recent hair sample, Oryx (2024). DOI: 10.1017/S0030605323001400

Comment by Dr. Krishna Kumari Challa on April 3, 2024 at 9:52am

How The Internet Travels Across Oceans

Comment by Dr. Krishna Kumari Challa on April 3, 2024 at 9:47am

A new window coating blocks heat, not view

Windows welcome light into interior spaces, but they also bring in unwanted heat. A new window coating blocks heat-generating ultraviolet and infrared light and lets through visible light, regardless of the sun's angle. The coating can be incorporated onto existing windows or automobiles and can reduce air-conditioning cooling costs by more than one-third in hot climates.

The coating maintains functionality and efficiency whatever the sun's position in the sky.

Seongmin Kim et al, Wide-angle spectral filter for energy-saving windows designed by quantum annealing-enhanced active learning, Cell Reports Physical Science (2024). DOI: 10.1016/j.xcrp.2024.101847

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Comment by Dr. Krishna Kumari Challa on April 3, 2024 at 9:43am

Semi-transparent camera allows for eye tracking without obstructing the view

A team of engineers has developed a nearly transparent camera that can be used for eye tracking without obstructing the view. The team has published a paper describing their camera and its performance as an eye tracker on the arXiv preprint server.

Using technology to track eye movement is beneficial in applications such as virtual reality helmets, automotive assistance devices and even advertising tracking. But the technology has remained stagnant due to one major problem—devices in front of the eyes obstruct the user's view. In this new effort, the researchers in Spain have overcome this problem by developing a camera that is nearly invisible.
To create their camera, the research team built a photodetector by adding small dots of lead sulfide to sheets of graphene. When struck by a photon, the dots emit electrons that flow across the layer of carbon atoms, producing a current. And because the materials used to create the photodetector are so small, they are nearly invisible to the naked eye—in tests, it was capable of allowing 95% of light to pass through it.

Further testing involved projecting greyscale patterns onto the photodetector and comparing the output with a standard image sensor. The researchers say the results are promising. They also noted that it had a refresh rate of 400Hz, approximately twice that needed for producing reliable imagery. They then simulated eye tracking by projecting a small dark dot onto the photodetector and used the output to track the action as it occurred.

In practice, the camera could potentially be applied to standard eyeglasses, or better yet, contact lenses. The researchers note, however, that more work is required before their camera could be used for such applications. The photodetector does not have a lens, for example, which means it only works with projected images—and there is the matter of processing imagery and adding a power source for the processor.

Gabriel Mercier et al, Semi-Transparent Image Sensors for Eye-Tracking Applications, arXiv (2024). DOI: 10.48550/arxiv.2403.08297

Comment by Dr. Krishna Kumari Challa on April 2, 2024 at 10:07am

Hypervitaminosis A refers to the toxic effects of ingesting too much preformed vitamin A

Diet – Liver is high in vitamin A. The liver of certain animals, including the polar bear, bearded seal, fish and walrus, are particularly toxic (see Liver (food) § Poisoning). It has been estimated that consumption of 500 grams (18 oz) of polar bear liver would result in a toxic dose for a human.

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