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Comment by Dr. Krishna Kumari Challa on September 4, 2024 at 7:05am

Why do typhoons like to cluster? Researchers identify key weather patterns

This August, Japan and South Korea, particularly Japan, have experienced a dramatic surge in typhoon activity. From August 8 to August 13, within just six days, Typhoons Maria, Son-Tinh, Ampil, and Wukong consecutively formed over the waters east of Japan. Among them, Tropical Storm Maria caused record-breaking rainfall in parts of northern Japan, while just a few days later, Typhoon Ampil arrived during Japan's Obon holiday week, causing significant damage in Japan.

This sequence of storms is a striking example of a phenomenon called multiple tropical cyclone (MTC) formation, where several typhoons either occur at the same time or follow one another in quick succession. The region typically sees about five of these clustering events each year, and their combined impact can significantly increase disaster risks and cause extensive damage.

So, why do typhoons seem to group together?

A recent study  by researchers sheds light on this puzzling question. Their research, published in Advances in Atmospheric Sciences, explores the key weather patterns that contribute to this clustering of tropical cyclones.

Part 1

Comment by Dr. Krishna Kumari Challa on September 4, 2024 at 7:01am

Self-healing hydrogel microparticles: A smart solution for advanced wound care

Chronic diabetic wounds are prevalent in patients and are difficult to heal, presenting a significant medical challenge. The development of multifunctional hydrogel dressings with a well-designed morphology and structure can enhance their flexibility and effectiveness in wound management.

Researchers have developed a self-healing hydrogel dressing based on structural color microspheres for wound management. Their research is published in the journal Nano-Micro Letters.

These microspheres are composed of an inverse opal framework with photothermal responsiveness, constructed from methacrylated hyaluronic acid, methacrylated silk fibroin, and black phosphorus quantum dots (BPQDs), and further embedded in dynamic hydrogels.

The dynamic hydrogel filler is formed through the Knoevenagel condensation reaction between cyanoacetate and benzaldehyde-functionalized dextran (DEX-CA and DEX-BA). Notably, the composite microspheres can be freely applied and, by utilizing the BPQD-mediated photothermal effect and the thermoreversible stiffness change of the dynamic hydrogel, can adhere to each other under near-infrared irradiation.

In addition, the microspheres are co-loaded with melittin and vascular endothelial growth factor, with a release behavior that can be regulated through the same mechanism. Additionally, the drug release process can be effectively monitored through visual color changes. This microsphere system demonstrates ideal capabilities in controlled drug release and efficient wound management.

Researchers also  evaluated the in vivo wound healing efficacy of composite microspheres (CMPs) in a full-thickness chronic diabetic wound infection model.

Statistical analysis of wound closure areas and regenerated epithelial thickness revealed that the group treated with the dual-drug-loaded CMPs combined with near-infrared (NIR) irradiation exhibited superior wound healing outcomes, significantly outperforming other groups. These results suggest that the synergistic effects of NIR-controlled irradiation and the intelligent responsiveness of CMPs play a crucial role in enhancing wound healing.

 Li Wang et al, Self-Healing Dynamic Hydrogel Microparticles with Structural Color for Wound Management, Nano-Micro Letters (2024). DOI: 10.1007/s40820-024-01422-4

Comment by Dr. Krishna Kumari Challa on September 4, 2024 at 6:55am

Hydrogel developed for use in slowing or stopping early stages of osteoarthritis

A team of material engineers and orthopedic specialists affiliated with several institutions in China has developed a hydrogel for slowing or stopping the progression of osteoarthritis. Their research is published in the journal Advanced Materials.

Osteoarthritis is a degenerative joint disease—it presents as a breakdown of the cartilage and the cushion-like tissue within the spaces where joints meet. The result is a reduction in lubrication and an increase in friction, preventing easy movement of the joint, and oftentimes, pain. It is due to multiple factors, such as an autoimmune response or poor exercise habits. The WHO has labeled the disease a global health crisis, affecting more than 528 million people in 2019.

Prior research has led to the development of therapies such as saline or corticosteroid injections, but neither fully reduce friction or pain, and the injections must be repeated every few months. In this new effort, the team in China developed a hydrogel that, once injected, performs much better than other treatments, according to the researchers.
The researchers made the hydrogel by mixing hollow spheres with polymer to create a slippery substance—the spheres are a mix of gelatin methacrylate and a poly(sulfobetaine methacrylate). Then, to get the hydrogel to stay in the joint where it is injected, they added a targeted antibody—one that binds to both the microspheres and damaged cartilage.

To test their hydrogel, the research team induced osteoarthritis in rats. They then injected the rats with their hydrogel and put them through exercise routines to measure the impact of the hydrogel on their ability to move normally.

The researchers found that injection of the hydrogel led to an increase in lubrication coinciding with a reduction in friction and reduced symptoms in rats. They also found that while present in the rat joints, the hydrogel prevented new joint damage.

The team also found that the hydrogel outperformed traditional therapies—they suggest it offers a promising approach to treating osteoarthritis during its early stages.

 Xiangming He et al, Precise Lubrication and Protection of Cartilage Damage by Targeting Hydrogel Microsphere, Advanced Materials (2024). DOI: 10.1002/adma.202405943

Comment by Dr. Krishna Kumari Challa on September 3, 2024 at 9:40am

Researchers built an AI scientist
Machine-learning researchers have developed an ‘AI scientist’ that can perform the full cycle of research, from reading the existing literature on a problem and formulating hypotheses, to trying out solutions, writing a paper, and evaluating its own results. The output is not earth-shattering: the system can only do research in the field of machine learning, and it can’t do laboratory work. But the results feed into a debate amongst researchers about how AI fits into their work, says computational social scientist Jevin West. “It does force us to think [about] what is science in the twenty-first century — what it could be, what it is, what it is not.”

https://arxiv.org/abs/2408.06292?utm_source=Live+Audience&utm_c...

https://www.nature.com/articles/d41586-024-02842-3?utm_source=Live+...

Comment by Dr. Krishna Kumari Challa on September 3, 2024 at 9:29am

When the rice fields were flooded, and arsenic was taken up, the researchers noticed methanogenesis happening, which is when organisms in the soil produce the potent greenhouse gas methane and emit it into the atmosphere. Meanwhile, the excess water reduced sulfate in the soil to sulfide, causing cadmium to precipitate out with the sulfide.

When they dried the soil out, the researchers decreased the levels of arsenic and methane. Sulfide in the soil was oxidized and became sulfate, which is no longer a solid phase, allowing cadmium to easily filter through and escape into the plant easily.

By drying out the soil, you can put the brakes on the microorganisms that breathe with iron oxides and with arsenic.

Then we actually increase the amount of cadmium because we oxidize the sulfide to sulfate. When it becomes sulfate, it's no longer a solid phase with the cadmium, and the cadmium can then be free.

Drying the soil out introduced oxygen into the soil pores, which slowed down the microorganisms that dissolve iron oxides and create methane and changed the chemistry.

Once you introduce oxygen, the iron oxides that dissolved are solid again.

What they found—one metal or metalloid increasing with the other decreasing depending on the level of moisture in the soil—presents a bit of a puzzle.

 researchers have also reported, in a review paper they published in the journal GeoHealth, that producers are willing to take any action needed to reduce levels of metals in their crops, but they need incentives, testing and education in order to do so.

Matt A. Limmer et al, Controlling exposure to As and Cd from rice via irrigation management, Environmental Geochemistry and Health (2024). DOI: 10.1007/s10653-024-02116-x

Angelia L. Seyfferth et al, Mitigating Toxic Metal Exposure Through Leafy Greens: A Comprehensive Review Contrasting Cadmium and Lead in Spinach, GeoHealth (2024). DOI: 10.1029/2024GH001081

Part 2

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Comment by Dr. Krishna Kumari Challa on September 3, 2024 at 9:26am

Curbing toxic metals in spinach and rice crops grown for baby food

Rice and spinach are staples for babies' and young children's diets, but toxic metals and metalloids found in those foods can cause severe health impacts.

In particular, heavy metals such as cadmium, lead, mercury, and metalloid arsenic could delay brain development in babies and young children.

In new research published in the academic journal Environmental Geochemistry and Health,  scientists have found that flooded rice fields tend to contain higher amounts of arsenic and lower amounts of cadmium. The drier those rice fields are, the lower the amounts of arsenic and the higher the amounts of cadmium. However, the higher cadmium is lower than the existing threshold for adverse health effects.

The findings could help establish a course of action for decreasing the levels of these contaminants in foods typically eaten by infants and children.

Crops such as corn, soybeans and wheat are grown in soils that are not very wet. So farmers water them to make sure the plants get the nutrients they need to grow, but never enough to fully flood them.

In contrast, rice is often grown in very wet, flooded soils. Oxygen that would normally reside in tiny pores in the soil gets lost very quickly and is replaced by water. The limited oxygen shifts the microorganisms in the soil, and those microorganisms start breathing with iron oxide minerals that give the soil a rusty orange color.

Arsenic likes to stick really tightly onto those iron oxides.

When the iron oxides are used by these organisms to breathe, they go from a solid mineral to a solution phase. You essentially dissolve them, and when you dissolve them, the arsenic that's stuck onto them goes into the water.  Once the arsenic is in the water, it can easily be absorbed by the rice roots and transported into the grain.

Scientists are trying to find an optimal irrigation management that minimized both arsenic and cadmium simultaneously.

Once they harvested the grain  scientists analyzed the amount of arsenic and cadmium in it and they  found that the more flooded the field, the more arsenic and less cadmium accumulated in the rice. By contrast, the drier the field, the more cadmium and less arsenic accumulated.

But, even under those drier conditions when there was more cadmium, the concentrations of cadmium in the grain were not of concern for human health.

Part 1

Comment by Dr. Krishna Kumari Challa on September 3, 2024 at 9:12am

Our latest results show no signs of dark matter. However, they let us rule out a lot of possibilities.

We found no traces of particles with masses above 1.6 × 10–26 kilograms, which is about 10-times as heavy as a proton.

These results are based on 280 days' worth of observations from the detector. Eventually, we aim to collect 1,000 days' worth—which will let us search for even more elusive potential dark matter particles.

If we're lucky, we might find dark matter turns up in the new data. If not, we have already begun to make plans for a next generation dark matter experiment. The XLZD (XENON-LUX-ZEPLIN-DARWIN) consortium is aiming to build a detector almost 10-times bigger that would allow us to trawl through even more of the space where these ubiquitous yet elusive particles may be hiding.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Part 3

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Comment by Dr. Krishna Kumari Challa on September 3, 2024 at 9:12am

The LZ experiment is located in an old goldmine about 1,500 meters below ground in South Dakota in the US. Placing the experiment deep underground helps to cut out as much background radiation as possible.

The experiment consists of a large double-walled tank filled with seven tons of liquid xenon, a noble gas chilled down to a temperature of 175 kelvin (–98°C).

If a dark matter particle smacks into a xenon nucleus, it should give off a tiny flash of light. Our detector has 494 light sensors to detect these flashes.
Of course, dark matter particles aren't the only things that can create these flashes. There is still some background radiation from the surroundings and even the materials of the tank and detectors themselves.

A big part of figuring out whether we are seeing signs of dark matter is disentangling this background radiation from anything more exotic. To do this, we make detailed simulations of the results we would expect to see with and without dark matter.

These simulations have been the focus of much of my part in the experiment, which began when I started my Ph.D. in 2015. I also developed detector monitoring sensors and was responsible for the integration and commissioning of the central detector underground, which began collecting data in 2021.
Part 2

Comment by Dr. Krishna Kumari Challa on September 3, 2024 at 9:11am

85% of the matter in the universe is missing: But scientists are getting closer to finding it

Most of the matter in the universe is missing. Scientists  think around 85% of the matter in the cosmos is made of invisible dark matter, which has only been detected indirectly by its gravitational effects on its surroundings.

A team of some 250 scientists from around the world working on a dark matter experiment called LUX-ZEPLIN (or LZ)—report our latest findings from the long quest to discover exactly what this dark matter is made of.

 They have not yet found the elusive particles we believe dark matter consists of, but they have set the tightest limits yet on their properties. They have also shown our detector is working as expected—and should produce even better results in the future.

When astronomers look at the universe, they see evidence that the visible matter of stars, gas and galaxies is not all there is. Many phenomena, such as how fast galaxies spin and the pattern of the residual glow of the Big Bang, can only be explained by the presence of large amounts of some invisible substance—dark matter.

So what is this dark matter made of? We currently don't know of any kind of particle that could explain these astronomical observations.

There are dozens of theories that aim to explain dark matter observations, ranging from exotic unknown particles to tiny black holes or fundamental changes to our theory of gravity. However, none of them has yet been proven correct.
One of the most popular theories suggests dark matter is made up of so-called "weakly interacting massive particles" (or WIMPs). These relatively heavy particles could cause the observed gravitational effects and also—very rarely—interact with ordinary matter.

How would we know if this theory is correct? Well, we think these particles must be streaming through Earth all the time. For the most part, they will pass through without interacting with anything, but every so often a WIMP might crash directly into the nucleus of an atom—and these collisions are what we are trying to spot.
Part 1

Comment by Dr. Krishna Kumari Challa on September 3, 2024 at 9:06am

In essence, the quartz acts like a natural battery, with gold as the electrode, slowly accumulating more gold with each seismic event.

This process could explain why large gold nuggets are so often associated with quartz veins formed in earthquake-related deposits.

This new understanding of gold nugget formation not only sheds light on a longstanding geological mystery but also highlights the interrelationship between Earth's physical and chemical processes.

Nature Geoscience (2024). www.nature.com/articles/s41561-024-01514-1

Part 2

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