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The search for new and better antimicrobial therapy is a continuous effort. Quercetin is a polyphenol with promising antimicrobial properties. However, the understanding of its antimicrobial mechanism is limited. In this study, we investigated the biochemical mechanistic action of quercetin as an antibacterial compound. Isolates of Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia, and Staphylococcus aureus were initially exposed to quercetin for antibacterial evaluation. Subsequently, S. aureus (Gram-positive) and E. coli (Gram-negative) cells were exposed to quercetin with or without ascorbic acid, and cells were harvested for selected biochemical assays. These assays included redox homeostasis (lipid peroxidation, total thiol, total antioxidant capacity), nitric oxide, and kynurenine concentration as well as DNA fragmentation. The results revealed that quercetin caused lipid peroxidation in the bacterial isolates. Lipid peroxidation may indicate ensuing oxidative stress resulting from quercetin treatment. Furthermore, tryptophan degradation to kynurenine was activated by quercetin in S. aureus but not in E. coli, suggesting that local L-tryptophan concentration might become limiting for bacterial growth. These findings, considered together, may indicate that quercetin restricts bacterial growth by promoting oxidative cellular stress, as well as by reducing the local L-tryptophan availability by activating the kynurenine pathway, thus contributing to our understanding of the molecular mechanism of the antimicrobial action of quercetin.Recent progress in the development of artificial intelligence technologies, aided by deep learning algorithms, has led to an unprecedented revolution in neuromorphic circuits, bringing us ever closer to brain-like computers. However, the vast majority of advanced algorithms still have to run on conventional computers. Thus, their capacities are limited by what is known as the von-Neumann bottleneck, where the central processing unit for data computation and the main memory for data storage are separated. Emerging forms of non-volatile random access memory, such as ferroelectric random access memory, phase-change random access memory, magnetic random access memory, and resistive random access memory, are widely considered to offer the best prospect of circumventing the von-Neumann bottleneck. This is due to their ability to merge storage and computational operations, such as Boolean logic. This paper reviews the most common kinds of non-volatile random access memory and their physical principles, together with their relative pros and cons when compared with conventional CMOS-based circuits (Complementary Metal Oxide Semiconductor). Their potential application to Boolean logic computation is then considered in terms of their working mechanism, circuit design and performance metrics. The paper concludes by envisaging the prospects offered by non-volatile devices for future brain-inspired and neuromorphic computation.Biopolymer-based superabsorbent polymers (SAPs) are being synthesized and investigated as a biodegradable alternative for an entirely synthetic SAPs, particularly those based on acrylic acid and its derivatives. This article focuses on the chemical modification of starch (S), and synthesis of new potentially biodegradable polymers using acrylic acid (AA) as side chain monomer and crosslinking mediator together with N,N’-methylenebisacrylamide (MBA). The graft co-polymerization was initiated by ceric ammonium nitrate (CAN) or potassium persulfate (KPS), leading to different reaction mechanisms. For each of the initiators, three different synthetic routes were applied. The structures of new bio-based SAPs were characterized by means of IR spectroscopy. Thermogravimetric measurements were made to test the thermal stability, and morphology of the samples were examined using scanning electron microscopy (SEM). Physico-chemical measurements were performed to characterize properties of new materials such as swelling characteristics. The water absorption capacity of resulting hydrogels was measured in distilled water and 0.9% NaCl solution.Calcium levels have a huge impact on the physiology of the female reproductive system, in particular, of the ovaries. Cytosolic calcium levels are influenced by regulatory proteins (i.e., ion channels and pumps) localized in the plasmalemma and/or in the endomembranes of membrane-bound organelles. Vismodegib research buy Imbalances between plasma membrane and organelle-based mechanisms for calcium regulation in different ovarian cell subtypes are contributing to ovarian pathologies, including ovarian cancer. In this review, we focused our attention on altered calcium transport and its role as a contributor to tumor progression in ovarian cancer. The most important proteins described as contributing to ovarian cancer progression are inositol trisphosphate receptors, ryanodine receptors, transient receptor potential channels, calcium ATPases, hormone receptors, G-protein-coupled receptors, and/or mitochondrial calcium uniporters. The involvement of mitochondrial and/or endoplasmic reticulum calcium imbalance in the development of resistance to chemotherapeutic drugs in ovarian cancer is also discussed, since Ca2+ channels and/or pumps are nowadays regarded as potential therapeutic targets and are even correlated with prognosis.In this study, a solution-processable compact vanadium oxide (V2O5) film with a globular nanoparticulate structure is introduced to the hole transport layer (HTL) of polymer bulk-heterojunction based solar cells comprised of PTB7PC70BM by using a facile metal-organic decomposition method to replace the conventionally utilized poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOTPSS). For this, a biocompatible structure-determining agent, polyethylene glycol (PEG, Mn 300), is used as an additive in the precursor to form the nanoparticulate compact V2O5 (hereafter referred to as NP-V2O5) film, which possesses an outstandingly smooth surface morphology. The introduction of NP-V2O5 HTL via the solution process with a neutral pH condition successfully improved the stability by preventing the decomposition of indium tin oxide (ITO) glass and the penetration of heavy-metal components and moisture, which are considered as the crucial drawbacks of using PEDOTPSS. Over 1440 h (60 days) of the stability test, an organic solar cell (OSC) with NP-V2O5 showed a significant durability, maintaining 82% of its initial power conversion efficiency (PCE), whereas an OSC with PEDOTPSS maintained 51% of its initial PCE.