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Comment by Dr. Krishna Kumari Challa on May 14, 2021 at 10:34am

A paradigm shift to combat indoor respiratory infection

Call for 'paradigm shift' to fight airborne spread of COVID-19 indoors

40 researchers from 14 countries in a call published in Science for a shift in standards in ventilation requirements equal in scale to the transformation in the 1800s when cities started organising clean water supplies and centralised sewage systems.

The international group of air quality researchers called on the World Health Organisation to extend the indoor air quality guidelines to include airborne pathogens and to recognise the need to control hazards of airborne transmission of respiratory infections.

https://science.sciencemag.org/content/372/6543/689

 L. Morawska at Queensland University of Technology in Brisbane, Australia el al., "A paradigm shift to combat indoor respiratory infection," Science (2021). science.sciencemag.org/cgi/doi … 1126/science.abg2025

https://phys.org/news/2021-05-paradigm-shift-airborne-covid-indoors...

Comment by Dr. Krishna Kumari Challa on May 14, 2021 at 10:13am

New evidence for electron's dual nature found in a quantum spin liquid

A new discovery led by Princeton University could upend our understanding of how electrons behave under extreme conditions in quantum materials. The finding provides experimental evidence that this familiar building block of matter behaves as if it is made of two particles: one particle that gives the electron its negative charge and another that supplies its magnet-like property, known as spin.

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Causes of concrete and asphalt deterioration explained

Scientists have revealed that the deterioration of modern concrete and asphalt structures is due to the presence of trace quantities of organic matter in these structures.

Comment by Dr. Krishna Kumari Challa on May 14, 2021 at 10:11am

Cancer has ripple effect on distant tissues

A new study with zebrafish shows that a deadly form of skin cancer—melanoma—alters the metabolism of healthy tissues elsewhere in the body. The research from Washington University in St. Louis suggests that these other tissues could potentially be targeted to help treat cancer.

Tumors rely on a constant supply of nutrients to grow. Instead of competing with tumors for nutrients, other tissues can reprogram their metabolism to be complementary. In some instances, this may even allow healthy tissues to feed the tumour. 

The scientists examined tissues in the liver, intestine, fin, muscle, brain, blood, and eye of the zebrafish that has melanoma.. They observed metabolic dysregulation across most of the tissues—indicating that melanoma broadly impacts whole-body metabolism.

Patti, Gary J. et al.: "Isotope tracing in adult zebrafish reveals alanine cycling between melanoma and liver" Cell Metabolism (2021). DOI: 10.1016/j.cmet.2021.04.014 , www.cell.com/cell-metabolism/f … 1550-4131(21)00180-7

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Cancer consumes tremendous amounts of glucose, a key source of energy for cells in the body. Glucose, or blood sugar, is derived from food and transported around the body through the bloodstream after eating. Tumors actively soak up glucose as a fuel to support their rapid growth.

This trait is so well known that physicians regularly use it as a diagnostic test for cancer, where patients are administered a specific form of glucose that can be monitored with a PET scan. What is less clear is how a tumor's penchant for glucose affects other tissues.

"Glucose levels are tightly regulated," Patti said. "When glucose levels get too low, it's dangerous. We wanted to know whether a tumor with a high avidity for glucose might influence glucose levels in the blood."

Even when healthy people go a long period of time without eating, blood glucose levels are kept relatively constant. That is because glucose can be made by the liver when it cannot be obtained directly from food.

As it turns out, the liver counters the impact of the tumor by synthesizing glucose. It's very similar to what occurs during a fast.

 the scientists observed that melanoma tissues in the body consume about 15 times more glucose than the other tissues they measured. Despite this burden, the zebrafish were able to maintain circulating glucose levels, apparently by making glucose in the liver through a process that is ordinarily triggered when we go without eating.

https://medicalxpress.com/news/2021-05-cancer-ripple-effect-distant...

Comment by Dr. Krishna Kumari Challa on May 14, 2021 at 9:55am

Food dyes may cause disease when the immune system is dysregulated, researchers report

Artificial food colorants can cause disease when the immune system has become dysregulated, researchers report. The study, published in Cell Metabolism in May, was the first to show this phenomenon.

The study, conducted in mice, found that the mice developed colitis when they consumed food with the artificial food colorants FD&C Red 40 and Yellow 6 when a specific component of their immune system, known as cytokine IL-23, was dysregulated. While it remains unclear whether food colorants have similar effects in humans, researchers plan to investigate exactly how cytokine IL-23 promotes the development of colitis after food colorant exposure.

Colitis is a form of inflammatory bowel disease (IBD), and cytokine IL-23 dysregulation is known to be a factor in the development of IBD in humans. Medicines that block its function are now successfully used in patients. Food colorants such as Red 40 and Yellow 6 are widely used in food, drink, and medicine. These two food colorants are the most commonly used in the world.

Both genetic predisposition and environmental factors appear to play a role in whether a person develops IBD, a condition that affects millions of people worldwide, but the exact environmental factors have remained elusive.

For the study, the researchers created mouse models that had a dysregulated expression of cytokine IL-23. To their surprise, the mice with the dysregulated immune response did not develop inflammatory bowel disease spontaneously even though dysregulated IL-23 is a factor in people with the disease.

When given a diet with the food dyes Red 40 or Yellow 6, the altered mice developed colitis. However, mice that had the dye-infused diet but had a normal immune system did not develop IBD. To prove that the food colorant was indeed responsible, the researchers fed the altered mice diets without the food colorant and water containing it; in both cases, the disease developed when the mice consumed the colorant, but not otherwise. They repeated this finding for several diets and several food colorants.

The dramatic changes in the concentration of air and water pollutants and the increased use of processed foods and food additives in the human diet in the last century correlate with an increase in the incidence of inflammatory and autoimmune diseases

https://medicalxpress.com/news/2021-05-food-dyes-disease-immune-dys...

https://www.eurekalert.org/pub_releases/2021-05/tmsh-fdm050621.php#...(May%2013,first%20to%20show%20this%20phenomenon.

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Comment by Dr. Krishna Kumari Challa on May 13, 2021 at 12:39pm

Tides Under Ocean’s Surface

Comment by Dr. Krishna Kumari Challa on May 13, 2021 at 11:41am

Study of ancient corals in Indonesia reveals slowest earthquake eve...

A slow-motion earthquake lasting 32 years—the slowest ever recorded—eventually led to the catastrophic 1861 Sumatra earthquake, researchers at the Nanyang Technological University, Singapore (NTU Singapore) have found.

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Study finds 'ghost forests' contribute to greenhouse gas emissions

A new study from North Carolina State University finds that greenhouse gas (GHG) emissions from standing dead trees in coastal wetland forests—colloquially called "tree farts"—need to be accounted for when assessing the environmental impact of so-called "ghost forests."

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Mechanism deciphered: How organic acids are formed in the atmosphere

The acidity of the atmosphere is increasingly determined by carbon dioxide and organic acids such as formic acid. The second of these contribute to the formation of aerosol particles as a precursor of raindrops and therefore impact the growth of clouds and pH of rainwater. In previous atmospheric chemistry models of acid formation, formic acid tended to play a small role. The chemical processes behind its formation were not well understood. An international team of researchers under the aegis of Forschungszentrum Jülich has now succeeded in filling this gap and deciphering the dominant mechanism in the formation of formic acid. This makes it possible to further refine atmosphere and climate models. The results of the study have now been published in the peer-reviewed journal Nature.

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A low-cost solution to remove arsenic from drinking water

High levels of a naturally occurring chemical called arsenic have been a source of contamination of ground-based drinking water, such as well-water, for people in many countries around the world, including parts of the United States. Consuming arsenic-contaminated water is a serious public health issue, leading to severe health complications including skin, lung, bladder, kidney and liver cancers, according to the National Institute of Environmental Health Sciences.

Comment by Dr. Krishna Kumari Challa on May 13, 2021 at 11:38am

Higher antibiotic doses may make bacteria 'fitter': study

Using higher doses of antibiotics in a bid to tackle the growing problem of drug resistance may end up strengthening certain bacteria, according to research released recently that highlights a previously unthought-of risk.

Previous research has shown that inflicting higher antibiotic doses on bacteria can slow its ability to develop resistance, yet little attention has been paid to how those higher doses impact the overall health of microbes.

A team of Britain- and Europe-based researchers looked at how populations of E. coli reacted to varying concentrations of three common antibiotics.

They found that while higher antibiotic doses slowed the rate at which the bacteria developed resistance, they also gave rise to bacteria with "higher overall fitness"—meaning it had a higher rate of reproduction.

"We consider growth rate as a proxy for fitness, under the assumption that a strain that grows faster is more likely to take over the population and become dominant.

This 

showed how higher antibiotic doses presented a "dilemma" and could result in ultimately more-resistant bacteria.

Considering the fitness of the evolved strains adds another dimension to the problem of optimal antibiotic dosing.

Mato Lagator et al. Adaptation at different points along antibiotic concentration gradients, Biology Letters (2021). DOI: 10.1098/rsbl.2020.0913

https://phys.org/news/2021-05-higher-antibiotic-doses-bacteria-fitt...

Comment by Dr. Krishna Kumari Challa on May 13, 2021 at 11:28am

Brand new physics of superconducting metals refuted by Lancaster physicists

Lancaster scientists have demonstrated that other physicists' recent "discovery" of the field effect in superconductors is nothing but hot electrons after all.

A team of scientists in the Lancaster Physics Department have found new and compelling evidence that the observation of the field effect in superconducting metals by another group can be explained by a simple mechanism involving the injection of the electrons, without the need for novel physics.

Dr. Sergey Kafanov, who initiated this experiment, said: "Our results unambiguously refute the claim of the electrostatic field effect claimed by the other group. This gets us back on the ground and helps maintain the health of the discipline."

The experimental team also includes Ilia Golokolenov, Andrew Guthrie, Yuri Pashkin and Viktor Tsepelin.

Their work is published in the latest issue of Nature Communications.

When certain metals are cooled to a few degrees above absolute zero, their electrical resistance vanishes—a striking physical phenomenon known as superconductivity. Many metals, including vanadium, which was used in the experiment, are known to exhibit superconductivity at sufficiently low temperatures.

For decades it was thought that the exceptionally low electrical resistance of superconductors should make them practically impervious to static electric fields, owing to the way the charge carriers can easily arrange themselves to compensate for any external field.

It therefore came as a shock to the physics community when a number of recent publications claimed that sufficiently strong electrostatic fields could affect superconductors in nanoscale structures—and attempted to explain this new effect with corresponding new physics. A related effect is well known in semiconductors and underpins the entire semiconductor industry.

The Lancaster team embedded a similar nanoscale device into a microwave cavity, allowing them to study the alleged electrostatic phenomenon at much shorter timescales than previously investigated. At short timescales, the team could see a clear increase in the noise and energy loss in the cavity—the properties strongly associated with the device temperature. They propose that at intense electric fields, high-energy electrons can "jump" into the superconductor, raising the temperature and therefore increasing the dissipation.

This simple phenomenon can concisely explain the origin of the "electrostatic field effect" in nanoscale structures, without any new physics.

Nature Communications (2021). DOI: 10.1038/s41467-021-22998-0

https://phys.org/news/2021-05-brand-physics-superconducting-metals-...

Comment by Dr. Krishna Kumari Challa on May 13, 2021 at 11:15am

How fasting diets could harm future generations

Fasting diets could impact the health of future generations according to new research .

Fasting diets have risen in popularity in recent years, however little is known about the long-term impact of these diets, particularly for future generations.

New research, published today in the journal Proceedings of the Royal Society B, reveals that reduced food intake in roundworms (Caenorhabditis elegans) has a detrimental effect on three generations of offspring—particularly when those descendants have access to unlimited food.

We know that reduced food intake increases the lifespan in many animals and can potentially improve health in humans. However, little is known about the long-term effects of reduced food intake, including time-limited fasting, on distant descendants.

The team investigated the effect of time-limited fasting on lifespan and reproduction in roundworms and across three generations of their descendants.

They studied more than 2,500 worms split across four generations. The first generation of worms were placed in one of four environments, including being able to eat as much as they liked, and being on a fasting diet.

Four generations of offspring from these parents were then placed onto either full-feeding or fasting diets.

The team then assessed the effects of different scenarios on the reproduction and longevity of future generations. These included what happens when great grandparents fast, but future generations are able to eat as much as they like, and cumulative fasting for four generations.

fasting did indeed increase their lifespan and it also improved offspring performance in terms of reproduction, when offspring themselves were fasting.

"However, we were surprised to find that fasting reduced offspring performance when the offspring had access to unlimited food.

"And this detrimental effect was evident in grand-offspring and great-grand-offspring.

This shows that fasting can be costly for descendants and this effect may last for generations.

"There has been a lot of interest in the potential benefits of fasting in promoting healthy aging in humans.

"A lot of the molecular pathways involved in the fasting response are evolutionarily conserved, which means the same pathways exist across a multitude of species including humans.

This study strongly prompts us to consider multigenerational effects of fasting in different organisms, including humans.

Edward R. Ivimey-Cook et al. Transgenerational fitness effects of lifespan extension by dietary restriction in Caenorhabditis elegans, Proceedings of the Royal Society B (2020). DOI: 10.1101/2020.06.24.168922

https://medicalxpress.com/news/2021-05-fasting-diets-future.html?ut...

Comment by Dr. Krishna Kumari Challa on May 13, 2021 at 10:08am

How to thermally cloak an object

Do you feel the heat? To a thermal camera, which measures infrared radiation, the heat that we can feel is visible, like the heat of a traveler in an airport with a fever or the cold of a leaky window or door in the winter.

Researchers now report a theoretical way of mimicking thermal objects or making objects invisible to thermal measurements. 

The method allows for fine-tuning of heat transfer even in situations where the temperature changes in time, the researchers say. One application could be to isolate a part that generates heat in a circuit (say, a power supply) to keep it from interfering with heat sensitive parts (say, a thermal camera). Another application could be in industrial processes that require accurate temperature control in both time and space, for example controlling the cooling of a material so that it crystallizes in a particular manner.

Just as our eyes see objects if they emit or reflect light, a thermal camera can see an object if it emits or reflects infrared radiation. In mathematical terms, an object could become invisible to a thermal camera if heat sources placed around it could mimic heat transfer as if the object wasn't there.

The novelty in the team's approach is that they use heat pumps rather than specially crafted materials to hide the objects. A simple household example of a heat pump is a refrigerator: to cool groceries it pumps heat from the interior to the exterior. Using heat pumps is much more flexible than using carefully crafted materials. So at least from the perspective of thermal measurements they can make an apple appear as an orange.

The researchers carried out the mathematical work needed to show that, with a ring of heat pumps around an object, it's possible to thermally hide an object or mimic the heat signature of a different object.

The work remains theoretical

Active Thermal Cloaking and Mimicking, Proceedings of the Royal Society A (2021). royalsocietypublishing.org/doi … .1098/rspa.2020.0941

https://phys.org/news/2021-05-thermally-cloak.html?utm_source=nwlet...

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