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Comment by Dr. Krishna Kumari Challa 12 hours ago

How to illuminate the ‘ugly’ side of science
Data repositories, workshops and alternative journals allow scientists to share and discuss negative results, which could help to solve the reproducibility crisis and give machine learning a boost. Publishing negative-result studies is often seen as not worth the time and effort, yet “understanding the reasons for null results can really test and expand our theoretical understanding”, says psychologist Wendy Ross. And highlighting negative results can help students to see that “you are not a bad researcher because you fail”, adds computer scientist Ella Peltonen.

https://www.nature.com/articles/d41586-024-01389-7?utm_source=Live+...

Comment by Dr. Krishna Kumari Challa 13 hours ago

Scientists pinpoint new vaccine adjuvant that promotes potent anti-tumor immunity

Scientists  have made an important breakthrough that offers promise for developing new immune therapies for cancer. They have discovered that a vaccine adjuvant called C100 promotes potent anti-tumor immunity when it is injected directly into tumors in an animal model.

The scientists found that C100, derived from chitin—one of the most common building materials in nature, and which gives strength to the exoskeletons of crustaceans, insects, and the cell walls of fungi—is highly effective at stimulating a key sensing and signaling molecule which regulates anti-tumor immune responses.

Their work has been published in Cell Reports Medicine.

The scientists now know how C100 exclusively activates one arm of a specific signaling pathway (cGAS-STING) without causing inflammatory responses that could interfere with anti-tumor immunity and which may otherwise prevent therapies from achieving clinical success.

Additionally, the research team discovered that injecting C100 led to synergistic therapeutic effects with a "checkpoint blocker," which can release the brakes on the immune response.

 Intratumoural delivery of the chitin-derived C100 adjuvant promotes robust STING, IFNAR and CD8+ T cell dependant anti-tumour immunity, Cell Reports Medicine (2024). DOI: 10.1016/j.xcrm.2024.101560. www.cell.com/cell-reports-medi … 2666-3791(24)00252-0

Comment by Dr. Krishna Kumari Challa 13 hours ago

Researchers estimate vaccines have saved 154 million lives over past half-century

An international team of health and medical researchers including workers at the WHO, working with economists and modeling specialists, has found that the use of vaccines to prevent or treat disease has saved the lives of approximately 154 million people over the past half-century.

In their study, published in The Lancet, the group used mathematical and statistical modeling to develop estimates for lives saved due to vaccines and then added them together to find the total. The goal of the team was to evaluate the degree of success of the Expanded Program on Immunization (EPI) launched by the World Health Organization in 1974. The goal of the EPI has been to vaccinate all the children in the world against the most common deadly diseases. At its onset, the list included seven diseases; it has since been expanded to include 14. As part of that effort, research has been conducted to develop vaccines, test them and then to use them once they have been declared both safe and effective. Since its inception, the EPI program has led to the development of many vaccines and the vaccination of millions of people, preventing suffering and death. In this new effort, the research team sought to find out how successful the program has been. The work involved collecting and analyzing data at the local, regional and global levels. As part of that effort, they created 22 models based on 50 years of vaccination data for people around the world. The team then used the models to estimate lives saved and found the total to be approximately 154 million since 1974. The research team also found that children benefited the most from vaccination—101 million of the lives saved were under the age of 1. They also found evidence that vaccination programs had a major impact on infant mortality rates—over the past half-century, rates have declined globally by 40%. The researchers also found that the measles vaccine made the biggest impact—it was responsible for 60% of the lives saved.

 Andrew J Shattock et al, Contribution of vaccination to improved survival and health: modelling 50 years of the Expanded Programme on Immunization, The Lancet (2024). DOI: 10.1016/S0140-6736(24)00850-X

Comment by Dr. Krishna Kumari Challa 13 hours ago

Study shows that astrocytes integrate information about past events in their soma

Neurons are known to communicate and integrate information they receive from their dendrites, branch-like structures extending from their body. In contrast, the activity in astrocytes, a class of star-shaped glial cells found in the central nervous system (CNS), has so far been assumed to be largely uncoordinated, thus lacking the central integration of information.

Researchers at University of Zurich and ETH Zurich recently gathered evidence suggesting that this widespread description of astrocytes might be false or at least incomplete, as they do in fact integrate information about past events.

Their findings, published in Nature Neuroscience, specifically reveal the conditional integration of calcium signals in processes taking place in the astrocytes' soma (i.e., cell body).

Peter Rupprecht et al, Centripetal integration of past events in hippocampal astrocytes regulated by locus coeruleus, Nature Neuroscience (2024). DOI: 10.1038/s41593-024-01612-8

Comment by Dr. Krishna Kumari Challa yesterday

Computer models suggest modern plate tectonics are due to blobs left behind by cosmic collision

A small team of geologists and seismologists  has found evidence via computer modeling that suggest giant blobs of material near the Earth's core, believed to have been created by a cosmic collision 4.5 billion years ago, may be responsible for modern plate tectonics.

In their study, published in the journal Geophysical Research Letters, the group used existing data on the blobs, known more technically as large, low-velocity provinces (LLVPs), and used it to create computer simulations and models showing their impact on the Earth over long time scales.

In the 1980s, geophysicists discovered what they described as giant blobs of unknown material near Earth's center—one below the Pacific Ocean, the other below parts of Africa. Then, last year,  another team found evidence that the blobs (LLVPs) are remnants of Theia, a planet that struck the Earth 4.5 billion years ago. The rest of the debris from the collision, theory suggests, coalesced in Earth's orbit, forming the moon.

For this new study, the team  used computer models to show what sort of impact the LLVPs may have had on the Earth's crust over the past millions of years, and report evidence that they may be responsible for modern plate tectonics.

Data for the models came from seismic readings that have shown the LLVPs are made up of different material than either the core or mantle. After some tweaking, the models showed that approximately 200 million years after Theia struck the Earth, pressure from the LLVPs led to the creation of hot plumes stretching from near the core to the surface. That caused some sections of the surface to sink, which led to subduction.

Subduction eventually led to the breaks in the surface that today serve as borders for tectonic plates. The researchers suggest their models may explain why some of the oldest minerals on Earth show evidence of subduction.

Qian Yuan et al, A Giant Impact Origin for the First Subduction on Earth, Geophysical Research Letters (2024). DOI: 10.1029/2023GL106723

Comment by Dr. Krishna Kumari Challa on Wednesday

What are nanoplastics? Concern is growing about particles too small to see

It's become common to read/hear that microplastics—little bits of plastic, smaller than a pencil eraser—are turning up everywhere and in everything, including the ocean, farmland, food and human bodies. Now a new term is gaining attention: nanoplastics. These particles are even tinier than microplastics—so small that they're invisible to the naked eye.

Nanoplastics are a type of microplastic, distinguished by their extremely small size. Microplastics are usually less than 5 millimeters across; nanoplastics are between 1 and 1,000 nanometers across. For comparison, an average human hair is roughly 80,000–100,000 nanometers wide.

Nanoplastics are attracting growing concern thanks to recent technological advances that have made researchers more able to detect and analyze them. Their smaller size means that they are more easily transported over long distances and into more diverse environments than microplastics. They can more easily penetrate cells and tissues in living organisms, which could lead to different and more acute toxicological effects.

Studies in the past two years have found nanoplastics in human blood, in liver and lung cells, and in reproductive tissues such as the placenta and the testes. Around the world, nanoplastics have been found in the air, in seawater, in snow and in soil.
We already know that microplastics are present from the heights of Mount Everest to deep ocean trenches. Now there is growing evidence that nanoplastics are more prevalent than larger microplastics in the environment.

Comment by Dr. Krishna Kumari Challa on Wednesday

Researchers show that slow-moving earthquakes are controlled by rock permeability

Earthquakes are the most dramatic and noteworthy results of tectonic plate movement. They are often destructive and deadly, or at the very least physically felt—they're literally groundbreaking geological events. However not all tectonic movement results in effects that humans can perceive.

Slow slip events occur when pent up tectonic forces are released over the course of a few days or months, like an earthquake unfolding in slow motion. The more gradual movement means people won't feel the earth shaking beneath their feet and buildings won't collapse. But the lack of destruction does not make slow slip events less scientifically important. In fact, their role in the earthquake cycle may help lead to a better model to predict when earthquakes happen.

In a paper published recently in Geophysical Research Letters, a Jackson School of Geosciences research group explores how the makeup of rocks, specifically their permeability—or how easily fluids can flow through them—affects the frequency and intensity of slow slip events.

Their tests showed how pores in the rocks could control the regular slow slip events at this subduction zone. Previous studies have suggested that a layer of impermeable rock at the top of the descending tectonic plate serves as a sealed lid, trapping fluid in the pores of underlying rock layers.

As fluid accumulates beneath the seal, the pressure builds, eventually becoming high enough to trigger a slow slip event or earthquake. This event then breaks the impermeable seal, temporarily fracturing the rocks, allowing them to soak up fluids. Within a few months, the rocks heal and return to their initial permeability, and the cycle starts all over again.

In this work,  for the first time, the researchers showed that using rocks that are representative of those at depth, that permeability is controlling slow slip events.

Nicola Tisato et al, Permeability and Elastic Properties of Rocks From the Northern Hikurangi Margin: Implications for Slow‐Slip Events, Geophysical Research Letters (2024). DOI: 10.1029/2023GL103696

Comment by Dr. Krishna Kumari Challa on Wednesday

Research team discovers new property of light

A research team headed by chemists  has discovered a previously unknown way in which light interacts with matter, a finding that could lead to improved solar power systems, light-emitting diodes, semiconductor lasers and other technological advancements.

 In a paper published recently in the journal ACS Nano, the scientists explain how they learned that photons can obtain substantial momentum, similar to that of electrons in solid materials, when confined to nanometer-scale spaces in silicon.

Silicon is Earth's second-most abundant element, and it forms the backbone of modern electronics. However, being an indirect semiconductor, its utilization in optoelectronics has been hindered by poor optical properties.

While silicon does not naturally emit light in its bulk form, porous and nanostructured silicon can produce detectable light after being exposed to visible radiation. Scientists have been aware of this phenomenon for decades, but the precise origins of the illumination have been the subject of debate.

In 1923, Arthur Compton discovered that gamma photons possessed sufficient momentum to strongly interact with free or bound electrons. This helped prove that light had both wave and particle properties, a finding that led to Compton receiving the Nobel Prize in physics in 1927.

In the present  experiments, researchers showed that the momentum of visible light confined to nanoscale silicon crystals produces a similar optical interaction in semiconductors.

This discovery of photon momentum in disordered silicon is due to a form of electronic Raman scattering. But unlike conventional vibrational Raman, electronic Raman involves different initial and final states for the electron, a phenomenon previously only observed in metals.

Sergey S. Kharintsev et al, Photon-Momentum-Enabled Electronic Raman Scattering in Silicon Glass, ACS Nano (2024). DOI: 10.1021/acsnano.3c12666

Comment by Dr. Krishna Kumari Challa on Wednesday

Adoption may be a lot easier to accept than infanticide, but it's actually more difficult to understand because it challenges Darwin's ideas about natural selection. It 's very interesting to see that the reproductive fitness outcomes 're about even between adoption and infanticide and suggests that they have an alternative strategy—adoption may be a non-violent means of getting genes into the next generation.

Steven R. Beissinger et al, Eviction-driven infanticide and sexually selected adoption and infanticide in a neotropical parrot, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2317305121

Part 2

Comment by Dr. Krishna Kumari Challa on Wednesday

Why parrots sometimes adopt—or kill—each other's babies

Infanticide and adoption in the animal kingdom have long puzzled scientists. While both males and females of many species are known to kill the babies of their rivals to secure sexual or social advantage, other animals have been observed caring for the young of dead or missing comrades.

A team of  biologists has discovered that both these extreme behaviours are surprisingly common among green-rumped parrotlets, a small South American parrot. In a new study in the journal Proceedings of the National Academy of Sciences, the researchers present nearly 30 years of observations revealing what drives the parrotlets to either care for—or kill—one another's babies.

In parrotlets, infanticide and adoption revolve around real estate and love, according to this research. Most of the infanticide attacks happened when a breeding pair was attacked by another pair that was trying to take over a coveted nest site. It also occurred when males wanted to breed with a widow who already had offspring—but we were surprised to find that these new males were just as likely to adopt the offspring as attack them."

Among parrotlets, competition over nesting sites appears to be the primary motivation for attacks. Parrotlets killed or wounded nestlings and eggs at 256 of the nests that the biologists monitored. In most cases, the attacks were carried out by a single parrotlet or a breeding pair that later claimed the nesting site for themselves.

These attacks occurred more often when the parrotlet population was high and competition for good nesting sites was fierce.

It's not that everybody's born a killer, but the urge to breed is very strong. When the resources provided by the environment aren't enough for all individuals to breed, they seek out alternative strategies. Unfortunately, that involves killing innocent little offspring.

Infanticide also occurred in nests where one parent had died and the surviving parent had found a new mate. However, these new mates were just as likely to adopt the unrelated offspring as kill them—and choosing to become a stepparent ultimately did not hurt the parrotlet's reproductive success.

part 1

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