STEM

[Cadavre Exquis]

COVID-19 Vaccine's mRNA Technology Adapted for First Antibiotic-Resistant Bacteria Vaccine
Posted by EditorDavid on Monday July 14, 2025 @07:34AM from the giving-it-a-shot dept.

Researchers have created the world's first mRNA-based vaccine against a deadly, antibiotic-resistant bacterium — and they did it using the platform developed for COVID-19 vaccines.

Medical Express publishes their announcement:

The vaccine developed by the team from the Institute for Biological Research and Tel Aviv University is an mRNA-based vaccine delivered via lipid nanoparticles, similar to the COVID-19 vaccine. However, mRNA vaccines are typically effective against viruses like COVID-19 — not against bacteria like the plague... In 2023, the researchers developed a unique method for producing the bacterial protein within a human cell in a way that prompts the immune system to recognize it as a genuine bacterial protein and thus learn to defend against it.

The researchers from Tel Aviv University and the Institute for Biological Research proved, for the first time, that it is possible to develop an effective mRNA vaccine against bacteria. They chose Yersinia pestis, the bacterium that causes bubonic plague — a disease responsible for deadly pandemics throughout human history. In animal models, the researchers demonstrated that it is possible to effectively vaccinate against the disease with a single dose.

The team of researchers was led by Professor Dan Peer at Tel Aviv University, a global pioneer in mRNA drug development, who says the success of the current study now "paves the way for a whole world of mRNA-based vaccines against other deadly bacteria."

Saludos.

[Cadavre Exquis]

https://elpais.com/ciencia/2025-08-03/la-odisea-de-tres-mujeres-y-el-bo-112-la-molecula-que-engana-al-cancer.html

Saludos.

[Cadavre Exquis]

Unitree Robotics · 2025.08.05 · Unitree Introducing | Unitree A2 Stellar Explorer

Saludos.

[Cadavre Exquis]

https://elpais.com/salud-y-bienestar/2025-08-07/fat-but-fit-estar-en-forma-podria-ser-un-mejor-predictor-de-longevidad-que-estar-delgado.html

Saludos.

[pollo]

https://yosefk.com/blog/llms-arent-world-models.html

LLMs aren’t world models

August 10th, 2025

I believe that language models aren’t world models. It’s a weak claim — I’m not saying they’re useless, or that we’re done milking them. It’s also a fuzzy-sounding claim — with its trillion weights, who can prove that there’s something an LLM isn't a model of? But I hope to make my claim clear and persuasive enough with some examples.

[...]

[pollo]

https://arstechnica.com/ai/2025/08/researchers-find-llms-are-bad-at-logical-inference-good-at-fluent-nonsense/

LLMs’ “simulated reasoning” abilities are a “brittle mirage,” researchers find

Chain-of-thought AI "degrades significantly" when asked to generalize beyond training.

In recent months, the AI industry has started moving toward so-called simulated reasoning models that use a "chain of thought" process to work through tricky problems in multiple logical steps. At the same time, recent research has cast doubt on whether those models have even a basic understanding of general logical concepts or an accurate grasp of their own "thought process." Similar research shows that these "reasoning" models can often produce incoherent, logically unsound answers when questions include irrelevant clauses or deviate even slightly from common templates found in their training data.

In a recent pre-print paper, researchers from the Arizona State University summarize this existing work as "suggest[ing] that LLMs are not principled reasoners but rather sophisticated simulators of reasoning-like text." To pull on that thread, the researchers created a carefully controlled LLM environment in an attempt to measure just how well chain-of-thought reasoning works when presented with "out of domain" logical problems that don't match the specific logical patterns found in their training data.

[...]

[Cadavre Exquis]

https://elpais.com/tecnologia/2025-08-12/un-tinte-para-crear-cristales-que-imitan-al-iris-facilita-la-conversion-de-rascacielos-e-invernaderos-en-centrales-energeticas.html

Saludos.

[Cadavre Exquis]

Can We Harness Light Like Nature for a New Era of Green Chemistry?
Posted by EditorDavid on Saturday August 16, 2025 @09:35PM from the taking-a-photosynthesis dept.

Sunlight becomes energy when plants convert four photons of light. But unfortunately, most attempts at synthetic light-absorbing chemicals can only absorb one photon at a time, write two researchers from the University of Melbourne. "In the Polyzos research group at the School of Chemistry, we have developed a new class of photocatalysts that, like plants, can absorb energy from multiple photons."

This breakthrough allows us to harness light energy more effectively, driving challenging and energy-demanding chemical reactions.

We have applied this technology to generate carbanions — negatively charged carbon atoms that serve as crucial building blocks in the creation, or synthesis, of carbon- and hydrogen-rich chemicals known as organic chemicals. Carbanions are vital in making drugs, polymers and many other important materials. However, traditional methods to produce carbanions often require lots of energy and dangerous reagents, and generate significant chemical waste, posing environmental and safety challenges... Our new method offers a greener, safer alternative [using visible light and renewable starting materials]...

We've used it to synthesize important drug molecules, including antihistamines, in a single step using simple, cheap and commonly available "commodity chemicals" — amines and alkenes. And importantly, the reaction scales well in commercial-scale continuous flow reactors, highlighting its potential for industrial applications.

"By learning from the subtle mastery of photosynthesis," the researchers write, their group "is forging a new paradigm for chemical manufacturing — one where sunlight powers sustainable and elegant solutions for the molecules that shape our world."

Saludos.

[Cadavre Exquis]

An alternative to LASIK—without the lasers

American Chemical Society edited by Sadie Harley, reviewed by Robert Egan · 2025.08.18

The electromechanical reshaping technique successfully flattened this rabbit cornea, shown in a cross section, from its original shape (white line) to a corrected one (yellow line). Credit: Daniel Kim and Mimi Chen

Millions of Americans have altered vision, ranging from blurriness to blindness. But not everyone wants to wear prescription glasses or contact lenses. Accordingly, hundreds of thousands of people undergo corrective eye surgery each year, including LASIK—a laser-assisted surgery that reshapes the cornea and corrects vision.

The procedure can result in negative side effects, prompting researchers to take the laser out of LASIK by remodeling the cornea, rather than cutting it, in initial animal tissue tests.

Michael Hill, a professor of chemistry at Occidental College, presented his team's results at the fall meeting of the American Chemical Society (ACS Fall 2025) held Aug. 17–21.

Human corneas are dome-shaped, clear structures that sit at the front of the eye, bending light from surroundings and focusing it onto the retina, where it's sent to the brain and interpreted as an image. But if the cornea is misshapen, it doesn't focus light properly, resulting in a blurry image. With LASIK, specialized lasers reshape the cornea by removing precise sections of the tissue.

This common procedure is considered safe, but it has some limitations and risks, and cutting the cornea compromises the structural integrity of the eye. Hill explains that "LASIK is just a fancy way of doing traditional surgery. It's still carving tissue—it's just carving with a laser."

But what if the cornea could be reshaped without the need for any incisions?

This is what Hill and collaborator Brian Wong are exploring through a process known as electromechanical reshaping (EMR). "The whole effect was discovered by accident," explains Wong, a professor and surgeon at the University of California, Irvine. "I was looking at living tissues as moldable materials and discovered this whole process of chemical modification."

American Chemical Society · 2025.08.18 · Surgery without scalpels | Headline Science

In the body, the shapes of many collagen-containing tissues, including corneas, are held in place by attractions of oppositely charged components. These tissues contain a lot of water, so applying an electric potential to them lowers the tissue's pH, making it more acidic. By altering the pH, the rigid attractions within the tissue are loosened and make the shape malleable. When the original pH is restored, the tissue is locked into the new shape.

Previously, the researchers used EMR to reshape cartilage-rich rabbit ears, as well as alter scars and skin in pigs. But one collagen-rich tissue that they were eager to explore was the cornea.

In this work, the team constructed specialized, platinum "contact lenses" that provided a template for the corrected shape of the cornea, then placed each over a rabbit eyeball in a saline solution meant to mimic natural tears. The platinum lens acted as an electrode to generate a precise pH change when the researchers applied a small electric potential to the lens.

After about a minute, the cornea's curvature conformed to the shape of the lens—about the same amount of time LASIK takes, but with fewer steps, less expensive equipment and no incisions.

They repeated this setup on 12 separate rabbit eyeballs, 10 of which were treated as if they had myopia, or nearsightedness. In all the "myopic" eyeballs, the treatment dialed in the targeted focusing power of the eye, which would correspond to improved vision.

The cells in the eyeball survived the treatment, because the researchers carefully controlled the pH gradient. Additionally, in other experiments, the team demonstrated that their technique might be able to reverse some chemical-caused cloudiness to the cornea—a condition that is currently only treatable through a complete corneal transplant.

Though this initial work is promising, the researchers emphasize that it is in its very early stages. Next up is what Wong describes as, "the long march through animal studies that are detailed and precise," including tests on a living rabbit rather than just its eyeball. They also plan to determine the types of vision correction possible with EMR, such as near- and far-sightedness and astigmatism.

Though the next steps are planned, uncertainties in the team's scientific funding have put them on hold. "There's a long road between what we've done and the clinic. But, if we get there, this technique is widely applicable, vastly cheaper and potentially even reversible," concludes Hill.

Saludos.