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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.

Comment by Dr. Krishna Kumari Challa on April 2, 2024 at 9:47am

Cancer Killers
Scientists have discovered a gene that might turn white blood cells into cancer cell eating machines. When researchers activated a gene called RAC in human macrophages (white blood cells that naturally engulf harmful substances) in the laboratory, the macrophages turned ravenous for human cancer cells.

Why this matters: A new cancer treatment in early-stage human trials reprograms macrophages to go after cancer calls, but the lead researchers were noticing the macrophages only “nibbling” away at the cancer cells. Activating the RAC gene in the macrophages might supercharge the cells’ “cannibalism” on cancer cells. Researchers hope this kind of therapy, called CAR-M, will be able to target solid tumors, such as breast or lung cancers.

macrophages turned ravenous for human cancer cells.

What the experts say: “This is certainly a really exciting translation between an observation of basic biology and applying it to how you could engineer a mammalian immune cell,” says Nathan Singh, an oncologist at Washington University School of Medicine in St. Louis.

Comment by Dr. Krishna Kumari Challa on April 2, 2024 at 9:46am

Strange Metals
Scientists have discovered a new class of materials called “strange metals,” which are characterized by confusing electronic behavior. The class includes a dozen or more materials, such as some copper oxide or iron-based superconductors and twisted bilayer graphene under certain conditions.

How it works: Regular metals are held together by chemical bonds between their atoms. The atoms share negatively charged electrons, and in some cases, the outermost electrons move from one atom to the next, carrying their negative charge with them. But in strange metals, electrons seem to lose their individual identities, acting more like a soup in which all the particles are connected through quantum entanglement.

What the experts say: "Understanding these metals may help us develop superconductors that might operate at or close to room temperature, potentially transforming power grids, quantum computing and medical devices,” writes Douglas Natelson, professor of physics at Rice University.

confusing electronic behavior.

Comment by Dr. Krishna Kumari Challa on April 2, 2024 at 9:13am

Albedo is highest in the frozen areas of the world, and mirror-like clean snow and ice with high levels of albedo reflect up to 90 percent of the sun's energy.

It is one of Earth's major cooling agents, along with lands and oceans that absorb excess heat and planet-warming greenhouse gas emissions.

Many countries have promised to plant billions of trees as a bulwark against global warming but not all efforts deliver for the planet equally, this study showed.

Moist, tropical environments like the Amazon and Congo Basin boasted high carbon storage and low changes in albedo, making them ideal locations for restoring forest cover.

The opposite was true in temperate grasslands and savanna.

Even projects in the best locations were probably delivering 20 percent less cooling than estimated when changes to 'albedo' were taken into account.

Restoring forests delivered undeniable benefits for people and the planet, such as supporting ecosystems and providing clean air and water, among many.

(But) we can't put trees everywhere. We don't have enough money or time or resources or people or seedlings.

And so it's really about making the most of limited investments and getting the greatest climate return per hectare of investment, according to researchers.

  Natalia Hasler et al, Accounting for albedo change to identify climate-positive tree cover restoration, Nature Communications (2024). DOI: 10.1038/s41467-024-46577-1

Part 2

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Comment by Dr. Krishna Kumari Challa on April 2, 2024 at 9:10am

Planting trees in wrong places heats the planet: Study

Planting trees in the wrong places can actually contribute to global warming, scientists said recently, but a new map identifies the best locations to regrow forests and cool the planet.

Trees soak up carbon dioxide and restoring areas of degraded woodlands or planting saplings to boost forest cover is one tool in the fight against climate change.

But in some cases, more trees means less sunlight is reflected back from the earth's surface and more heat is absorbed by the planet, according to a study in the journal Nature Communications.

There are some places where putting trees back leads to net climate negative outcomes. Scientists had already understood that restoring tree cover led to changes in albedo—the amount of solar radiation bounced back off the planet's surface—but didn't have the tools to account for it.

Using new maps, researchers were able to consider, for the first time, the cooling effect from trees and the warming caused by decreased albedo.

They found that projects that didn't factor albedo into the equation overestimated the climate benefit of additional trees by between 20 to 80 percent.

But the maps also provide the tools to help policymakers identify where best to funnel scarce resources for maximum climate impact.

There's also lots of places still where restoring tree cover is a great idea for climate change  Scientists are  just trying to help people find those spots.

Part 1

Comment by Dr. Krishna Kumari Challa on April 1, 2024 at 8:49am

To understand the reasons for different shapes of hyphae, researchers combined theory and experiments to investigate fungi and water molds from across nature. They first employed physics-based models of inflationary tip growth to determine all "possible" shapes of hyphae. Surprisingly, the shapes of "actual" hyphae found in nature assumed only a small subset of the possible shapes.

The researchers hypothesized that the limited shapes observed in nature reflected "survival of the fittest," and that the many possible shapes not observed in real fungi were, for some reason, weaker evolutionary rejects. To explore this idea, they examined the growth rate of hyphae with different shapes to create a fitness landscape for hyphae.

Their eureka moment came when they realized that the shapes of hyphae were intimately connected to their ability to grow fast.

A fitness landscape is like a topographic map that visualizes the evolution of an organism: every species wanders through its fitness landscape by testing whether or not random mutations in its genes increase its growth rate, or fitness. A species only stops its restless wandering when a new mutation decreases its fitness—that is, when it is at a fitness peak.

However, researchers found that fitness landscapes can be much more rich than a system of peaks and valleys. In fact, they found that the fitness landscape for hyphae contained an overhanging cliff, or tipping point, and that this acts as a barrier to evolution, strongly limiting the shapes of fungal hyphae. Accordingly, they predicted that hyphae with shapes near the brink of the tipping point would be particularly vulnerable to small environmental, chemical, or genetic changes.

The researchers tested their prediction by treating fungi near the tipping point with small amounts of chemicals that affected hyphal growth. They used one chemical that reduces pressure within the hyphae and another derived from a sea sponge that blocks the hypha's ability to deliver cellular components to the tip of the cell. Both treatments caused the same dramatic effect: the hyphae elongated much more slowly and with a strange nub shape not found in nature.

These findings explain hyphal shape diversity in an enormous, diverse, and important group of species. More broadly, they also demonstrate an important new evolutionary principle: that fitness landscapes can have instabilities, or tipping points, that impose strict constraints on complex traits, like biological form. 

The researchers think that their results have critical implications for our understanding of many ecological and evolutionary systems. For example, those species whose evolution is subject to a tipping point may be the most vulnerable to the gradual increase in temperature caused by climate change.

Their findings could also aid in the development of new antimicrobials against disease-causing fungi by identifying vulnerabilities in their growth associated with an evolutionary tipping point.

A fitness landscape instability governs the morphological diversity of tip-growing cells, Cell Reports (2024). DOI: 10.1016/j.celrep.2024.113961. www.cell.com/cell-reports/full … 2211-1247(24)00289-4

Part 2

Comment by Dr. Krishna Kumari Challa on April 1, 2024 at 8:43am

Researchers discover evolutionary 'tipping point' in fungi

Scientists have found a "tipping point" in the evolution of fungi that throttles their growth and sculpts their shapes. The findings, published in the journal Cell Reports, demonstrate how small changes in environmental factors can lead to huge changes in evolutionary outcomes.

Fungi are nature's great composters. They wait within the forest floor  to feed on fallen trees and autumn leaves, releasing essential nutrients from these plants back into the Earth.

Although fungi often bring to mind mushroom caps, fungi also have underground "roots" called mycelia. Mycelia are made up of thousands of interconnected, microscopic, finger-like cells called hyphae that grow into vast networks. Hyphae worm their way through the soil by growing from their tips. To do so, they inflate themselves, similar to the long balloons used to make balloon animals.

Their elongated forms allow hyphae to locate and consume nutrients within the soil. But not all hyphae are the same shape: some have rounded tips, while others are pointed. The hyphae of water molds—fungus-like pathogens that cause blight in crops—are particularly pointy.

A major challenge in biology is to identify the specific evolutionary factors that determine the shape—or form—of a given organism.

Part 1

Comment by Dr. Krishna Kumari Challa on March 30, 2024 at 9:34am

People with diabetes, atrial fibrillation (a common type of irregular heart rhythm) and treated high blood pressure were at highest risk of going on to develop heart and circulatory diseases.
Nearly half of those at highest risk smoked or were living with obesity. Modeling showed that if all current smokers living with obesity were supported to lose weight and quit smoking, the mean 10-year risk in this group would fall from nearly 22% to around 16%.

 Kelvin P Jordan et al, Determining cardiovascular risk in patients with unattributed chest pain in UK primary care: an electronic health record study, European Journal of Preventive Cardiology (2023). DOI: 10.1093/eurjpc/zwad055

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