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Comment by Dr. Krishna Kumari Challa on August 8, 2024 at 8:46am

Domestication causes smaller brain size in dogs than in the wolf: Study challenges notion

A recent study, published in Biology Letters, challenges the long-held notion that domestication is the primary driver of reduced brain size in domesticated animals, specifically dogs.

Employing a phylogenetic comparative approach, researchers  show that the domesticated dog does not exhibit an exceptionally small brain relative to its body size compared to other canid species, suggesting that  domestication is not as unique an evolutionary force as previously thought.

The prevailing belief has been that domestication leads to a significant reduction in brain size due to relaxed selection pressures, such as reduced need for foraging, mating competition, and predator avoidance.

This phenomenon is thought to be a result of the decreased necessity for metabolically costly brain tissue in a domesticated environment. While domesticated dogs show a substantial decrease in brain size compared to their wild ancestor, the gray wolf (Canis lupus), this study aimed to determine if this reduction is exceptional when viewed in a broader phylogenetic context.

Researchers analyzed brain and body size data for 25 canid species, including ancient dog breeds that are genetically closer to the ancestral domesticated dog.

Their phylogenetic predictions and allometric regressions showed that the reduction in brain size in domesticated dogs is not an unambiguous evolutionary singularity. The observed brain size in dogs fell within the expected range for most ancient breeds used in the study, suggesting that domestication is not uniquely influential in reducing brain size among canids.

Interestingly, the study found that the common raccoon dog (Nyctereutes procyonoides), which hibernates, is a more pronounced outlier in terms of brain size reduction. Hibernation, associated with prolonged periods of low metabolic activity and food scarcity, is hypothesized to constrain brain size evolution due to the high energy demands of large brains.

Part 1

Comment by Dr. Krishna Kumari Challa on August 7, 2024 at 10:54am

What Your Nails Say About Your Health

https://youtu.be/PRftXdvENRw?si=VgUs4ne4n_eT2KL_

Comment by Dr. Krishna Kumari Challa on August 7, 2024 at 9:29am

Looking inside a microchip with 4 nanometer precision: New X-ray world record

Researchers  have used X-rays to look inside a microchip with higher precision than ever before. The image resolution of 4 nanometers marks a new world record. The high-resolution three-dimensional images of the type they produced will enable advances in both information technology and the life sciences.

The researchers  reported their findings in the current issue of the journal Nature.

Since 2010, the scientists have been developing microscopy methods with the goal of producing three-dimensional images in the nanometer range. In their current research, they have succeeded for the first time in taking pictures of state-of-the-art computer chips microchips with a resolution of 4 nanometers—a world record.

Instead of using lenses, with which images in this range are not currently possible, the scientists resort to a technique known as ptychography, in which a computer combines many individual images to create a single, high-resolution picture. Shorter exposure times and an optimized algorithm were key to significantly improving upon the world record they themselves set in 2017. For their experiments, the researchers used X-rays from the Swiss Light Source SLS at PSI.

Tomas Aidukas et al, High-performance 4-nm-resolution X-ray tomography using burst ptychography, Nature (2024). DOI: 10.1038/s41586-024-07615-6

Comment by Dr. Krishna Kumari Challa on August 7, 2024 at 9:03am

This could involve examining patients who have a restricted orexin system for genetic reasons—this is the case in around one in two thousand people. These people suffer from narcolepsy (a sleeping disorder). Another possibility would be to observe people who receive a drug that blocks orexin. Such drugs are authorized for patients with insomnia.

If we understand how the brain arbitrates between food consumption and physical activity, we can develop more effective strategies for addressing the global obesity epidemic and related metabolic disorders.
Interventions could be developed to help overcome exercise barriers in healthy individuals and those whose physical activity is limited.

Orexin neurons mediate temptation-resistant voluntary exercise, Nature Neuroscience (2024). DOI: 10.1038/s41593-024-01696-2

Comment by Dr. Krishna Kumari Challa on August 7, 2024 at 9:01am

 How our brain decides what to do

 What exactly happens in our brain when we make a decision has been a mystery till now. But researchers  have found the solution. They have deciphered which brain chemical and which nerve cells mediate this decision: the messenger substance orexin and the neurons that produce it.

These neuroscientific fundamentals are relevant because many people don't take good decisions like getting enough exercise because they don't find it easy to decide. Most of us have probably already decided once or even several times to skip exercising in favor of one of the numerous alternative temptations of daily life. According to the World Health Organization, 80% of adolescents and 27% of adults don't get enough exercise. And obesity is increasing at an alarming rate not only among adults but also among children and adolescents.

Despite these statistics, many people manage to resist the constantly present temptations and get enough exercise.

In their experiments with mice, the researchers were able to show that orexin plays a key role in taking decisions. It's one of over a hundred messenger substances that are active in the brain. Other chemical messengers, such as serotonin and dopamine, were discovered a long time ago and their role has largely been decoded. The situation for orexin is different: Researchers discovered it relatively late, around 25 years ago, and they are now clarifying its functions step by step.

In neuroscience, dopamine is a popular explanation till now  for why we choose to do some things but avoid others. This brain messenger is critical for our general motivation. However, our current knowledge about dopamine does not easily explain why we decide to exercise instead of eating. Our brain releases dopamine both when we eat and when we exercise, which does not explain why we choose one over the other.

To find out what does explain this, the researchers devised a sophisticated behavioral experiment for mice, which were able to choose freely from among eight different options in ten-minute trials. These included a wheel they could run on and a "milkshake bar" where they could enjoy a standard strawberry-flavored milkshake.

"Mice like a milkshake for the same reason people do: It contains lots of sugar and fat and tastes good.

In their experiment, the scientists compared different groups of mice: one made up of normal mice and one in which the mice's orexin systems were blocked, either with a drug or through genetic modification of their cells.

The mice with an intact orexin system spent twice as much time on the running wheel and half as much time at the milkshake bar as the mice whose orexin system had been blocked. Interestingly, however, the behavior of the two groups didn't differ in experiments in which the scientists only offered the mice either the running wheel or the milkshake.

This means that the primary role of the orexin system is not to control how much the mice move or how much they eat. Rather, it seems central to making the decision between one and the other, when both options are available. Without orexin, the decision was strongly in favor of the milkshake, and the mice gave up exercising in favour of eating.

researchers expect that orexin may also be responsible for this decision in humans; the brain functions involved here are known to be practically the same in both species.

The researchers are now trying to verify this  in humans too.

Part 1

Comment by Dr. Krishna Kumari Challa on August 7, 2024 at 8:50am

'Cool paint' for cars to keep drivers cooler

Car companies are trying  "cool paint" to keep people inside vehicles cooler, although the coating is six times thicker, making commercialization still a challenge.

The vehicles with the special paint looked like ordinary cars, but felt much cooler to the touch.

The cool paint lowered the cars' roof-panel temperature by 12 degrees Celsius (22 degrees Fahrenheit) and the interiors by 5 C (9 F).

Cooling materials are already widely used in buildings and other items. Cooler cars can reduce use of air-conditioning and relieve the toll from heat on engines and electric vehicle batteries.

They have  also been experimenting with paint that delivers lower cabin temperatures, mostly focusing on colours that refract the sun's rays.

The cool paint reflects sunlight better and also creates electromagnetic waves that block the rays, redirecting energy away from vehicles.

Source: Various news agencies

Comment by Dr. Krishna Kumari Challa on August 6, 2024 at 12:01pm

This Super-Black Material Made of Wood Can Absorb 99.3% of Light

A new super-black wood-based material has been created that absorbs more than 99 percent of the light that hits it. 

Researchers were working on water-repelling technologies for wood, using high-energy plasma gas – and noticed that the application of the gas turned the ends of wood cells completely black. Further examination revealed the incredible light absorption properties of the new super-black material.

The researchers  named their new material Nxylon.

Nxylon's composition combines the benefits of natural materials with unique structural features, making it lightweight, stiff and easy to cut into intricate shapes.

The material has a velvety appearance, its inventors report. The plasma treatment actually changes the tiny structures on the surface of the wood, introducing indentations that help to capture light and minimize any reflections.

Indeed, when a gold alloy was applied to the material, it remained black. This shows that the structure of the wood has changed – this isn't just an extra coating, but a reconfiguration of the fundamentals of the material.

Super-black materials are valuable in industries like astronomy, solar energy, and optics, where they help devices function more accurately or efficiently by reducing unwanted light reflection. For example, super-black materials can reduce glare and improve clarity on telescopes.

https://onlinelibrary.wiley.com/doi/10.1002/adsu.202400184

Comment by Dr. Krishna Kumari Challa on August 6, 2024 at 9:50am

According to a US national database, cases of liver toxicity linked to botanical use, some severe or even fatal, nearly tripled between 2004 and 2014—from 7% of cases to 20%. Use of turmeric, green tea extract, Garcinia cambodgia were often implicated. Another study found such cases rising from 12.5% of liver toxicity cases in 2007 to 21.1% by 2015.
Who's using these botanicals? According to the new study, the most common consumer is an older (average age about 52) white (75% of users) female (57%), who was typically well-off.

People taking botanicals were more likely to be battling some kind of chronic illness, such as arthritis, thyroid disorders or cancer, compared to folks not using the supplements.
In two-thirds of cases, people took a botanical while also taking a prescription medicine, the study found. Because of the danger of drug interactions and the threat to liver health, it's crucial that botanical users inform their doctors, the research group said.
When botanicals are overused, the damage to the liver "can not only be severe, leading to hepatocellular [liver] injury with jaundice, but also fatal, leading to death or liver transplantation," the research team warned.

A prior study found that the number of liver transplants required due to botanical overuse jumped by 70% between 2009 and 2020.

 Alisa Likhitsup et al, Estimated Exposure to 6 Potentially Hepatotoxic Botanicals in US Adults, JAMA Network Open (2024). DOI: 10.1001/jamanetworkopen.2024.25822

Part 2

Comment by Dr. Krishna Kumari Challa on August 6, 2024 at 9:47am

Excessive use of botanicals like turmeric, green tea are harming  livers

Botanicals like turmeric, green tea and black cohosh may seem benign, but their overuse is being increasingly linked to liver injury.

New research suggests that thousands are using at least one of the several leading botanicals. Many are ending up in hospitals for liver toxicity, researchers report.

Because there's almost no  regulatory oversight over botanicals, chemical tests of products linked to liver crises show frequent discrepancies between product labels and detected ingredients.

The researchers focused on the use of six of the most popular botanicals: Turmeric, green tea extract, the Garcinia cambodgia plant, black cohosh, red yeast rice and ashwagandha.

Millions of adults regularly take turmeric supplements, often with the notion that it can ease pain or arthritis. Unfortunately, "multiple randomized clinical trials have failed to demonstrate any efficacy of turmeric-containing products in osteoarthritis," and overdoing it on turmeric has been linked to serious liver toxicity, the researchers said.

Likewise, millions of  adults are estimated to be taking another potential liver toxin, green tea extract, usually to help boost energy and aid in weight loss.

But again, "multiple studies have failed to demonstrate any objective evidence of weight loss and sustained improvement in mood or energy levels" with products containing the active ingredients in green tea extract, the research  team noted.

Other claims, many unfounded, are made for other botanicals: Garcinia cambodgia is touted for weight loss, black cohosh for easing hot flashes and ashwagandha to help build muscle. But scientists noted that consumers may be overdosing on botanicals, or getting misled by labels that don't reflect the actual ingredients in their supplements. That may be leading to more users ending up in the ER.

Part 1

Comment by Dr. Krishna Kumari Challa on August 6, 2024 at 8:51am

Physicists develop new method to combine conventional internet with the quantum internet

Researchers  have developed a new transmitter-receiver concept for transmitting entangled photons over an optical fiber. This breakthrough could enable the next generation of telecommunications technology, the quantum internet, to be routed via optical fibers. The quantum internet promises eavesdropping-proof encryption methods that even future quantum computers cannot decrypt, ensuring the security of critical infrastructure.

In their experiment, the researchers demonstrated that the entanglement of photons is maintained even when they are sent together with a laser pulse. The research results were published in Science Advances.

The physicists could change the colour of a laser pulse with a high-speed electrical signal so that it matches the colour of the entangled photons. This effect enables them to combine laser pulses and entangled photons of the same colour in an optical fiber and separate them again.

This effect could integrate the conventional internet with the quantum internet.

Their experiment shows how the practical implementation of hybrid networks can succeed.

 Philip Rübeling et al, Quantum and coherent signal transmission on a single-frequency channel via the electro-optic serrodyne technique, Science Advances (2024). DOI: 10.1126/sciadv.adn8907

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