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This unique material can behave like a fluid, flowing and deforming with minimal resistance, yet it can also instantly become rigid, acting like a solid. It’s called PAM (or Polycatenated Architected Material). Its unique structure, inspired by chain mail, features interlinked shapes forming intricate three-dimensional networks. Unlike traditional materials, which are either solid with fixed structures or granular with loose, independent particles, PAMs occupy a fascinating middle ground. When subjected to shear stress, for example, the interconnected components can slide past each other, offering little resistance, much like water or honey. However, when compressed, these same components lock together, creating a rigid structure. This transition between fluid and solid-like behavior is what makes PAMs so unique. PAMs represent a new class of matter, defying the traditional classification of materials as either solid or granular. They are a hybrid, bridging the gap between these two extremes. This dynamic behavior is achieved through the intricate design of PAMs. Researchers at Caltech create these materials using 3D printing. They begin by modeling the structures on a computer, mimicking crystal lattices but replacing the fixed particles with interconnected rings or cages. These designs are then brought to life using various materials, from polymers to metals. The resulting PAMs, often small cubes or spheres, undergo rigorous testing to understand their response to different forces. They are compressed, sheared, and twisted, revealing their unusual properties. The potential applications for PAMs are vast and varied. Their ability to absorb energy efficiently makes them ideal candidates for protective gear, such as helmets, potentially offering superior protection compared to current foam-based solutions. This same property could also be utilized in packaging and other applications requiring cushioning or stabilization. Experiments with microscale PAMs have shown that they respond to electrical charges, suggesting possibilities in biomedical devices and soft robotics. Researchers are also exploring the vast design space of PAMs, using advanced techniques like artificial intelligence to discover new configurations and functionalities. While still in its early stages, PAM research promises to revolutionize material science and engineering, opening up new possibilities for a wide range of applications.

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Imagine smartphones that can diagnose diseases, detect counterfeit drugs or warn of spoiled food. Spectral sensing is a powerful technique that identifies materials by analyzing how they interact with light, revealing details far beyond what the human eye can see.

Traditionally, this technology required bulky, expensive systems confined to laboratories and industrial applications. But what if this capability could be miniaturized to fit inside a smartphone or ?

Researchers at Aalto University in Finland have combined miniaturized hardware and intelligent algorithms to create a powerful tool that is compact, cost-effective, and capable of solving real-world problems in areas such as health care, food safety and autonomous driving. The research is published in the journal Science Advances.

Researchers have used quantum physics and machine learning to quickly and accurately understand a mound of data – a technique, they say, could help extract meaning from gargantuan datasets.

Their method works on groundwater monitoring, and they’re trialling it on other fields like traffic management and medical imaging.

“Machine learning and artificial intelligence is a very powerful tool to look at datasets and extract features,” Dr Muhammad Usman, a quantum scientist at CSIRO, tells Cosmos.

In this study, we have demonstrated the crucial role of NAD+ homeostasis, particularly through the de novo synthesis pathway mediated by Qprt, in maintaining spermatogenesis with age. The deletion of Qprt led to progressive declines in NAD+ levels, particularly after 6 months of age, which were associated with significant defects in germ cell survival and mitochondrial function in spermatocytes. These disruptions manifested as impaired progression through meiosis, defective DNA double-strand break repair, and abnormal meiotic sex chromosome inactivation. Our findings also highlight the therapeutic potential of NAD+ precursor supplementation, as nicotinamide riboside effectively rescued the observed spermatogenic abnormalities in Qprt-deficient mice, emphasizing the importance of NAD+ in reproductive health and aging.

NAD+ can be synthesized through three pathways: the Preiss-Handler pathway, the salvage pathway, and the de novo pathway (Liu et al. 2018 ; Harjes 2019). In the de novo pathway, the essential amino acid tryptophan serves as a substrate, with Qprt catalyzing the formation of nicotinic acid mononucleotide, which is subsequently converted into NAD+ via a series of enzymatic reactions in the Preiss-Handler pathway. Coordinated regulation of these three pathways is crucial for maintaining intracellular NAD+ levels, which are essential for cellular function, a decline in NAD+ levels can lead to various pathological and physiological conditions (Minhas et al. 2019 ; Zhang et al. 2019a). In this study, we identified that Qprt, the rate-limiting enzyme in the NAD+ de novo synthesis pathway, is predominantly expressed in spermatocytes within the testes.

Recent advances in the fields of human-infrastructure interaction, electronic engineering, robotics and artificial intelligence (AI) have opened new possibilities for the development of assistive and medical technologies. These include devices that can assist individuals with both physical and cognitive disabilities, supporting them throughout their daily activities.

Researchers at the University of Michigan recently developed CoNav, a smart controlled via a Robot Operating System (ROS) based framework. The new wheelchair, presented in a paper on the arXiv preprint server, could help to improve the quality of life of individuals who are temporarily or permanently unable to walk, allowing them to move in their surroundings more intuitively and autonomously.

“The inspiration for this work stems from a broader challenge in assistive mobility for people with disabilities (PWD),” Vineet Kamat, senior author of the paper, told Tech Xplore.

The Sudan virus, a close relative of Ebola, has a fatality rate of 50% but remains poorly understood in terms of how it infects cells. Currently, no approved treatments exist. To address this critical gap in pandemic preparedness, researchers at the University of Minnesota and the Midwest Antiviral Drug Discovery (AViDD) Center investigated how this deadly virus attaches to human cells.

Like Ebola, the Sudan virus enters cells by binding to NPC1, a protein responsible for cholesterol transport. Using , the researchers mapped how the Sudan virus interacts with the human NPC1 receptor. Their findings revealed that four key amino acid differences in the receptor-binding proteins of Sudan and Ebola viruses enable the Sudan virus to bind to human NPC1 with nine times greater affinity than Ebola, which may contribute to its high fatality rate.

Building on this discovery, the team predicted the receptor-binding affinities of three other filoviruses closely related to Sudan and Ebola. They also examined how the Sudan virus binds to NPC1 receptors in bats, which are believed to be natural hosts of filoviruses. These findings provide crucial insights into the infection mechanisms and evolutionary origins of Sudan virus and related filoviruses, paving the way for potential treatments.

An international team of engineers and physicists have found a way to use quantum light to improve the performance of cutting-edge spectroscopy.

Their new technique enables measurements of infrared electric fields which are twice as sensitive as previous developments in a process called time-domain spectroscopy.

The researchers say their work could help open up new applications in security and medical diagnostics.

Question Were the liberalization of medical cannabis and the legalization of nonmedical cannabis in Canada associated with changes in the population-attributable fraction of cannabis use disorders associated with schizophrenia?

Findings In this population-based cohort study comprising 13 588 681 individuals, the population-attributable fraction of cannabis use disorder associated with schizophrenia increased significantly from 3.7% in the prelegalization period to 10.3% during the postlegalization period.

Meaning These findings suggest that the association between cannabis use disorders and schizophrenia is an important consideration for the legalization of cannabis.