Non-neural cells can mimic memory-like behavior. These cells ‘remember’ chemical patterns over time, showing that memory mechanisms aren’t exclusive to the brain but rely on fundamental cellular processes.
Category: chemistry – Page 32
Donald J. Cram, a Nobel Prize-winning chemist who taught andconducted research at UCLA for more than 50 years and is remembered bythousands of undergraduates for singing and playing guitar in class, died ofcancer June 17 at his home in Palm Desert. He was 82.
A renowned scientist who was as comfortable riding the waveswith friends in the San Onofre Surfing Club as he was in his lab at UCLAconstructing complex molecular models, Cram won the Nobel Prize in 1987 and theNational Medal of Science in 1993 for his work in host-guest chemistry, a fieldhe helped to create. In 1998, he wasranked among the 75 most important chemists of the past 75 years byChemical and Engineering News.
“DonaldCram stands alone in the incredible variety, beauty and depth of hisaccomplishments,” read the citation for Cram’s National Medal of Science. “His investigations have helped give thisscience its form and sophistication. Hetruly brought art to science by making his science an art.”
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Ever since then, researchers have marveled at the bedbug’s resilience. No matter what kind of chemical insecticide we throw at it, they manage to survive. This is due in large part to its development of insecticide resistance. Recent research conducted by Hidemasa Bono at Hiroshima University found that a series of genetic mutations explain the bedbug’s resistance to insecticides.
To figure that out, Bono and his team took a peek at the genome of an insecticide-resistant bedbug. They then compared it to bedbug samples collected in 2010 from a hotel in Hiroshima, along with wild bedbugs dating back to the 1950s. They used a technique called long-read sequencing to create nearly free and nearly error-free genomic maps to compare the various bedbugs across time. This allowed them to see several different mutations across the three types of bedbugs.
They found that the bedbug that came from the hotel had 19,895 times more resistance to one of the most common types of insecticide, pyrethroids, than the nonresistant genome. All told, they identified 729 resistant specific mutations. Some of these mutations are related directly to DNA damage response, cell cycle regulation, and insulin metabolism.
Summary: A new “molecular lantern” technique allows researchers to monitor molecular changes in the brain non-invasively using a thin light-emitting probe. This innovative tool utilizes Raman spectroscopy to detect chemical changes caused by tumors, injuries, or other pathologies without altering the brain beforehand.
Unlike prior methods requiring genetic modifications, this approach analyzes natural brain tissue with high precision, offering significant potential for diagnosing and studying brain diseases. Future developments aim to integrate artificial intelligence to enhance diagnostic accuracy and explore diverse biomedical applications.
At first glance, it might seem obvious that atoms touch each other, especially when you consider the material world around us. From the objects we handle to the materials we utilize, everything indeed appears very solid. However, the question of whether atoms actually “touch” as we understand it on a human level is far more intricate than it might seem. In fact, the answer hinges on how we define “touch,” a concept that shifts significantly at the atomic scale.
At the human scale, “touch” generally refers to the meeting of well-defined surfaces. For instance, when you place a glass on a table, you might say the two objects are touching because their outer surfaces overlap. However, at the atomic scale, this notion of contact becomes much more ambiguous. An atom is neither a solid object nor an entity with a clear boundary. It consists of a central nucleus made up of protons and neutrons, surrounded by a cloud of constantly moving electrons. This unpredictable movement means the electron cloud does not create a fixed and defined surface.
To understand what contact means between atoms, one must look into the internal structure of these particles and the interactions occurring between their electrons. Each atom is made up of a central nucleus surrounded by an electron cloud, which isn’t located at a specific spot but occupies areas known as orbitals. These orbitals are regions of probability where it’s more or less likely to find an electron at any given time. Their shape and organization vary depending on the chemical element of the atom, giving each type of atom unique characteristics.
Decades of research have established that chronic stress—from money worries, job problems, family tensions, or other sources—causes chemical changes in the body. In a new study, researchers have identified biological changes induced by stress that may help explain how it could cause a tumor to spread, or metastasize.
To conduct the study, the researchers used two established methods for modeling stress in mice. One is designed to mimic exposure to constant, low-level, predictable stress. The other simulates intermittent, unpredictable, mild stress.
They used these methods to induce chronic stress in two different mouse models of breast cancer. In both models, when the mice were exposed to stress using either method, they had both larger mammary tumors and more lung metastases than mice not exposed to stress.
But a series of follow-up experiments strongly suggested that this increased tumor growth and metastasis wasn’t being driven by the effects of stress on cancer cells themselves.
Misfolded proteins may preserve postmortem brains well after other tissues have decayed.
By Kermit Pattison edited by Tanya Lewis
No part of our body is as perishable as the brain. Within minutes of losing its supply of blood and oxygen, our delicate neurological machinery begins to suffer irreversible damage. The brain is our most energy-greedy organ, and in the hours after death, its enzymes typically devour it from within. As cellular membranes rupture, the brain liquifies. Within days, microbes may consume the remnants in the stinky process of putrefaction. In a few years, the skull becomes just an empty cavity.
Basic Machine learning and it’s application in solid state physics: An approach to identify the crystalline structure of solids
Posted in chemistry, particle physics, robotics/AI | Leave a Comment on Basic Machine learning and it’s application in solid state physics: An approach to identify the crystalline structure of solids
All solids have a crystal structure that shows the spatial arrangement of atoms, ions or molecules in the lattice. These crystal structures are often determined by a method known as X-ray diffraction technique (XRD).
These crystal structures play an import role in determining many physical properties such as the electronic band structure, cleavage and explains many of their physical and chemical properties.
This article aims to discuss an approach to identify these structures by various machine learning and deep learning methods. It demonstrates how supervised machine learning and deep learning approaches and help in determining various crystal structures of solids.
Princeton engineers have developed a scalable 3D printing technique to produce soft plastics with customizable stretchiness and flexibility, while also being recyclable and cost-effective—qualities rarely combined in commercially available materials.
In a study published in Advanced Functional Materials, a team led by Emily Davidson detailed how they used thermoplastic elastomers—a class of widely available polymers—to create 3D-printed structures with adjustable stiffness. By designing the 3D printer’s print path, the engineers could program the plastic’s physical properties, allowing devices to stretch and flex in one direction while remaining rigid in another.
Davidson, an assistant professor of chemical and biological engineering, highlighted the potential applications of this technique in fields such as soft robotics, medical devices, prosthetics, lightweight helmets, and custom high-performance shoe soles.
Zhao, N., Zhang, CJ., Zhang, X. et al. npj Regen Med 9, 42 (2024). https://doi.org/10.1038/s41536-024-00387-7