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Comment by Dr. Krishna Kumari Challa on August 10, 2023 at 12:20pm

In those spots, and to a lesser extent globally, new studies show a possible warming from the loss of sulfur pollution. And the trend is in places where it really can't be explained as easily by El Niño. There was a cooling effect that was persistent year after year, and suddenly it was removed.

In January 2022, the Hunga Tonga-Hunga Ha'apai undersea volcano in the South Pacific blew, sending more than 165 million tons of water, which is a heat-trapping greenhouse gas as vapour. The volcano also blasted 550,000 tons (500,000 metric tons) of sulfur dioxide into the upper atmosphere. A couple of studies use computer models to show a warming effect from all that water vapour.

However, the studies that showed warming from Hunga Tonga didn't incorporate sulfur cooling, which is hard to do.

Scientists 're still just trying to figuring it out.

Lesser suspects in the search include a dearth of African dust, which cools like sulfur pollution, as well as changes in the jet stream and a slowdown in ocean currents.

Some nonscientists have looked at recent solar storms and increased sunspot activity in the sun's 11-year cycle and speculated that Earth's nearest star may be a culprit. However, for decades, scientists have tracked sunspots and solar storms, and they don't match warming temperatures.

Solar storms were stronger 20 and 30 years ago, but there is more warming now.

 Still, other scientists said there's no need to look so hard. They say human-caused climate change, with an extra boost from El Niño, is enough to explain recent temperatures. The fact that the world is coming out of a three-year La Niña, which suppressed global temperatures a bit, and going into a strong El Niño, which adds to them, makes the effect bigger.

Climate change and El Niño can explain it all. That doesn't mean other factors didn't play a role. But we should definitely expect to see this again without the other factors being present.

Source: The Associate Press

Part 2

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Comment by Dr. Krishna Kumari Challa on August 10, 2023 at 12:12pm

Scientists look beyond climate change and El Nino for other factors that heat up Earth

Scientists are trying to find out if global warming and El Niño have an accomplice in fueling this summer's record-shattering heat.

The European climate agency Copernicus reported that July was one-third of a degree Celsius (six-tenths of a degree Fahrenheit) hotter than the old record. That's a bump in heat that is so recent and so big, especially in the oceans and even more so in the North Atlantic, that scientists are split on whether something else could be at work.

Scientists agree that by far the biggest cause of the recent extreme warming is climate change from the burning of coal, oil and natural gas that has triggered a long upward trend in temperatures. A natural El Niño, a temporary warming of parts of the Pacific that changes weather worldwide, adds a smaller boost. But some researchers say another factor must be present.

One surprising source of added warmth could be cleaner air resulting from new shipping rules. Another possible cause is 165 million tons (150 million metric tons) of water spewed into the atmosphere by a volcano. Both ideas are under investigation.

Shipping is "probably the prime suspect". Maritime shipping has for decades used dirty fuel that gives off particles that reflect sunlight in a process that actually cools the climate and masks some of global warming.

In 2020, international shipping rules took effect that cut as much as 80% of those cooling particles, which was a "kind of shock to the system". The sulfur pollution used to interact with low clouds, making them brighter and more reflective, but that's not happening as much now.

Part 1

Comment by Dr. Krishna Kumari Challa on August 10, 2023 at 11:59am

World's largest study shows the more you walk, the lower your risk of death, even if you walk fewer than 5,000 steps

The number of steps you should walk every day to start seeing benefits to your health is lower than previously thought, according to the largest analysis to investigate this.

The study, published in the European Journal of Preventive Cardiology recently, found that walking at least 3967 steps a day started to reduce the risk of dying from any cause, and 2337 steps a day reduced the risk of dying from diseases of the heart and blood vessels (cardiovascular disease). However, the new analysis of 226,889 people from 17 different studies around the world has shown that the more you walk, the greater the health benefits. The risk of dying from any cause or from cardiovascular disease decreases significantly with every 500 to 1000 extra steps you walk. An increase of 1000 steps a day was associated with a 15% reduction in the risk of dying from any cause, and an increase of 500 steps a day was associated with a 7% reduction in dying from cardiovascular disease.

They found that even if people walked as many as 20,000 steps a day, the health benefits continued to increase. They have not found an upper limit yet.

This study confirms that the more you walk, the better. They found that this applied to both men and women, irrespective of age, and irrespective of whether you live in a temperate, sub-tropical or sub-polar region of the world, or a region with a mixture of climates. In addition, this analysis indicates that as little as 4,000 steps a day are needed to significantly reduce deaths from any cause, and even fewer to reduce deaths from cardiovascular disease.

There is strong evidence that a sedentary lifestyle may contribute to an increase in cardiovascular disease and a shorter life. Studies have shown that insufficient physical activity affects more than a quarter of the world's population.

According to World Health Organization data, insufficient physical activity is the fourth most frequent cause of death in the world, with 3.2 million deaths a year related to physical inactivity.

Maciej Banach et al, The Association Between Daily Step Count and All-Cause and Cardiovascular Mortality: A Meta-Analysis, European Journal of Preventive Cardiology (2023). DOI: 10.1093/eurjpc/zwad229

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Comment by Dr. Krishna Kumari Challa on August 9, 2023 at 11:29am

Microwaving 'Safe' Plastics Can Release Billions of Particles, Scientists Warn

Billions of nanometer-wide particles can be released from plastic containers into the food they're holding when they're microwaved, a new study reveals. A team from the University of Nebraska-Lincoln in the US ran experiments using baby food containers made from polypropylene and polyethylene, which are both approved as safe to use by the regulators at the US Food and Drug Administration (FDA).

After three minutes of being heated in a 1,000-watt microwave, a variety of liquids put inside the containers were analyzed for microplastics (at least 1/1,000th of a millimeter in diameter) and nanoplastics (even smaller).

Particle numbers varied, but the researchers estimated that 4.22 million microplastic and 2.11 billion nanoplastic particles from only one square centimeter of plastic could be released during those three minutes of microwave heating.

Microwaving water or dairy products inside polypropylene or polyethylene products is likely to deliver the highest relative concentrations of plastic, the researchers revealed. Particles were also released when food and drinks were refrigerated and stored at room temperature, but significantly fewer in number.

What's not clear right now is what these microscopic plastic particles are doing to us. Studies have shown they can potentially be harmful to the intestine and key biological processes, but it's an area scientists aren't sure about.

It's probably safe to say that the less plastic we're ingesting the better, though. Embryonic kidney cells cultured by the researchers and exposed to plastic particles at levels of concentrations released by the containers over several days revealed a potential for concern.

The team found 77 percent of the kidney cells exposed to the highest levels of plastic were killed off. While this isn't to say our own kidneys would necessarily be exposed directly to such concentrations, it gives us some idea of the potential toxicity of these microplastics and nanoplastics – particular in developing bodies.

https://pubs.acs.org/doi/10.1021/acs.est.3c01942

Comment by Dr. Krishna Kumari Challa on August 9, 2023 at 10:34am

Asteroid Mining & Orbital Settlements

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Comment by Dr. Krishna Kumari Challa on August 9, 2023 at 9:57am

In mice, just three days of a fat-rich diet is enough to cause this inflammation. Other studies have shown that this inflammation can raise the threshold at which animals are full—in other words, they have to eat more food than usual to feel full.

Inflammation may explain why the hypothalamus is larger in these individuals, the team say. One suggestion is that the body reacts to inflammation by increasing the size of the brain's specialist immune cells, known as glia.

The team say more research is needed to confirm whether increased volume in the hypothalamus is a result of being overweight or whether people with larger hypothalami are predisposed to eat more in the first place. It is also possible that these two factors interact with each other causing a feedback loop.

Stephanie S.G. Brown Conceptualisation et al, Hypothalamic volume is associated with body mass index, NeuroImage: Clinical (2023). DOI: 10.1016/j.nicl.2023.103478

Part 2

Comment by Dr. Krishna Kumari Challa on August 9, 2023 at 9:55am

Brain's 'appetite control center' found to be different in people who are overweight or living with obesity

Scientists have shown that the hypothalamus, a key region of the brain involved in controlling appetite, is different in the brains of people who are overweight and people with obesity when compared to people who are a healthy weight.

The researchers say their findings add further evidence to the relevance of brain structure to weight and food consumption.

A large number of factors influence how much we eat and the types of food we eat, including our genetics, hormone regulation, and the environment in which we live. What happens in our brains to tell us that we are hungry or full is not entirely clear, though studies have shown that the hypothalamus, a small region of the brain about the size of an almond, plays an important role.

Researchers  used an algorithm developed using machine learning to analyze MRI brain scans taken from 1,351 young adults across a range of BMI scores, looking for differences in the hypothalamus when comparing individuals who are underweight, healthy weight, overweight and living with obesity.

In a study published in Neuroimage: Clinical, the scientists found that the overall volume of the hypothalamus was significantly larger in the overweight and obese groups of young adults. In fact, they found a significant relationship between volume of the hypothalamus and body-mass index(BMI).

These volume differences were most apparent in those sub-regions of the hypothalamus that control appetite through the release of hormones to balance hunger and fullness.

While the precise significance of the finding is unclear—including whether the structural changes are a cause or a consequence of the changes in body weight—one possibility is that the change relates to inflammation. Previous animal studies have shown that a high fat diet can cause inflammation of the hypothalamus, which in turn prompts insulin resistance and obesity.

Part 1

Comment by Dr. Krishna Kumari Challa on August 8, 2023 at 11:09am

Mosquito-dwelling microbe stops malaria
Malaria-carrying mosquitoes are less likely to pass on the parasite that causes the disease if they are infected with a naturally occurring bacterium. The microbe secretes a chemical that hobbles the malaria parasite’s development in the insects’ guts. So far, researchers trying to prevent the spread of the disease have had to rely on genetically modified bacteria — a major obstacle to regulatory and public acceptance, says malaria researcher Carolina Barillas-Mury. In experiments, one-third of mice bitten by bacterium-carrying mosquitoes became infected, compared with 100% of those bitten by regular malaria mosquitoes. And the mosquitoes don’t seem to develop resistance against the bacterium as they do to insecticides. The approach “has great potential to be implemented”.

 https://www.science.org/doi/10.1126/science.adf8141

Comment by Dr. Krishna Kumari Challa on August 8, 2023 at 10:44am

Scientists observe first evidence of 'quantum superchemistry' in the laboratory

A research team  has announced the first evidence for "quantum superchemistry"—a phenomenon where particles in the same quantum state undergo collective accelerated reactions. The effect had been predicted, but never observed in the laboratory till now.

The findings, published July 24 in Nature Physics, open the door to a new field. Scientists are intensely interested in what are known as "quantum-enhanced" chemical reactions, which could have applications in quantum chemistry, quantum computing, and other technologies, as well as in better understanding the laws of the universe.

Near absolute zero, particles can link up so that they are all in the same quantum state—where they can display unusual abilities and behaviors. It had been theorized that a group of atoms and molecules in the same quantum state would behave differently during chemical reactions, but the difficulty in orchestrating the experiment meant it had never been observed.

In the experiments, the scientists cooled down cesium atoms and coaxed them into the same quantum state. Next, they watched as the atoms reacted to form molecules. In ordinary chemistry, the individual atoms would collide, and there's a probability for each collision to form a molecule. However, quantum mechanics predicts that atoms in a quantum state perform actions collectively instead. You are no longer treating a chemical reaction as a collision between independent particles, but as a collective process. All of them are reacting together, as a whole.

One consequence is that the reaction happens faster than it would under ordinary conditions. In fact, the more atoms in the system, the faster the reaction happens.

Another consequence is that the final molecules share the same molecular state.

the same molecules in different states can have different physical and chemical properties —but there are times when you want to create a batch of molecules in a specific state. In traditional chemistry, you're rolling the dice. But with this technique, you can steer the molecules into an identical state.

Researchers  saw evidence that the reaction was taking place as a three-body interaction more often than as a two-body interaction. That is, three atoms would collide; two would form a molecule, and the third remained single. But the third played some role in the reaction.

 Zhendong Zhang et al, Many-body chemical reactions in a quantum degenerate gas, Nature Physics (2023). DOI: 10.1038/s41567-023-02139-8

Comment by Dr. Krishna Kumari Challa on August 8, 2023 at 10:22am

Therefore, linking this increased and consistent supply of methane to the Late Paleozoic Ice Age, which had a peak in atmospheric methane 304 million years ago, may suggest that the combined contribution from numerous alkaline lakes globally could have had a significant impact on global greenhouse gas levels. The researchers suggest that, taking the lakes in northwest China alone, methane emissions could have reached 109 gigatonnes, which is equivalent to the greenhouse forcing power of up to 7521 gigatonnes of carbon dioxide.

Clearly this highlights the potency of methane in affecting our climate, and specifically the importance of identifying alkaline lakes globally to monitor their current emissions and find solutions to help combat their activity. This can include reducing the pH of the lakes so that they become more acidic, adding certain types of clay or even dredging the lake bottom, but all of these solutions naturally introduce a host of their own effects on the environment. As such, there may not yet be a clear solution to reducing methane emissions from lakes and abating their global warming potential.

Liuwen Xia et al, Effects on global warming by microbial methanogenesis in alkaline lakes during the Late Paleozoic Ice Age (LPIA), Geology (2023). DOI: 10.1130/G51286.1

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