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Netgear has fixed two critical vulnerabilities affecting multiple WiFi router models and urged customers to update their devices to the latest firmware as soon as possible.
The security flaws impact multiple WiFi 6 access points (WAX206, WAX214v2, and WAX220) and Nighthawk Pro Gaming router models (XR1000, XR1000v2, XR500).
Although the American computer networking company did not disclose more details about the two bugs, it did reveal that unauthenticated threat actors can exploit them for remote code execution (tracked internally as PSV-2023–0039) and authentication bypass (PSV-2021–0117) in low-complexity attacks that don’t require user interaction.
Nicotinamide Riboside Supplementation Alleviates Testicular Aging Induced by Disruption of Qprt‐Dependent NAD+ De Novo Synthesis in Mice
Posted in biotech/medical, life extension, sex | Leave a Comment on Nicotinamide Riboside Supplementation Alleviates Testicular Aging Induced by Disruption of Qprt‐Dependent NAD+ De Novo Synthesis in Mice
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.
A darkened patch of endobronchial mucosa was found during bronchoscopy in a 55-year-old man with a history of orthotopic liver transplantation complicated by post-transplantation Kaposi’s sarcoma.
Scientists at Osaka University have designed a nanogate that opens and closes using electrical signals, offering precise control over ions and molecules.
This tiny innovation has the potential to transform sensing technology, chemical reactions, and even computing. By adjusting voltage, researchers can manipulate the gate’s behavior, making it a versatile tool for cutting-edge applications.
Nanogates: control at the macro and nanoscale.
A circuit containing four superconducting devices called Josephson junctions can be finely tuned for various technological applications.
A research team at POSTECH has developed a novel multidimensional sampling theory to overcome the limitations of flat optics. Their study not only identifies the constraints of conventional sampling theories in metasurface design but also presents an innovative anti-aliasing strategy that significantly enhances optical performance. Their findings were published in Nature Communications.
Flat optics is a cutting-edge technology that manipulates light at the nanoscale by patterning ultra-thin surfaces with nanostructures. Unlike traditional optical systems that rely on bulky lenses and mirrors, flat optics enables ultra-compact, high-performance optical devices. This innovation is particularly crucial in miniaturizing smartphone cameras (reducing the “camera bump”) and advancing AR/VR technologies.
Metasurfaces, one of the most promising applications of flat optics, rely on hundreds of millions of nanostructures to precisely sample and control the phase distribution of light. Sampling, in this context, refers to the process of converting analog optical signals into discrete data points—similar to how the human brain processes visual information by rapidly capturing multiple images per second to create continuous motion perception.
A pair of physicists at the University of Crete has found that some types of biological magnetoreceptors used by various creatures to navigate, operate at or near the quantum limit. In their paper published in the journal PRX Life, I. K. Kominis and E. Gkoudinakis describe how they worked the problem of magnetic sensing in tiny animals in reverse by putting bounds on unknown quantum boundaries, and what it showed about the navigation abilities of certain animals.
Prior research has shown that many creatures use the Earth’s magnetic field as a navigation aid. Some sharks, fish and birds, for example, use it to help them traverse long distances. Different animals also have different types of magnetic sensors, including radical-pair, induction and magnetite mechanisms.
Radical-pair works by sensing correlations between unpaired electrons attached to certain molecules. Induction works by turning energy in the magnetic field into electricity and then sensing the electrical charge. And magnetite-based magnetoreception involves sensing the movement or orientation of tiny iron crystals in the body, similar to a human-made compass.
When people think about fiber optic cables, it’s usually about how they’re used for telecommunications and accessing the internet. But fiber optic cables—strands of glass or plastic that allow for the transmission of light—can be used for another purpose: imaging the ground beneath our feet.
MIT Department of Earth, Atmospheric and Planetary Sciences (EAPS) Ph.D. student Hilary Chang recently used the MIT fiber optic cable network to successfully image the ground underneath campus using a method known as distributed acoustic sensing (DAS). By using existing infrastructure, DAS can be an efficient and effective way to understand ground composition, a critical component for assessing the seismic hazard of areas, or how at risk they are from earthquake damage.
“We were able to extract very nice, coherent waves from the surroundings, and then use that to get some information about the subsurface,” says Chang, the lead author of a recent paper describing her work that was co-authored with EAPS Principal Research Scientist Nori Nakata. The study is published in The Leading Edge journal.