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Dynamic modeling and adaptive variable constraint optimization for integrated energy systems based on double-loop framework
Novel anti-prion compounds screening in prion-infected cell culture model combined with surface plasmon resonance analysis
Mechanistic basis of antimicrobial resistance mediated by the phosphoethanolamine transferase MCR-1
Abstract Polymyxins are used to treat infections caused by multidrug-resistant Gram-negative bacteria. They are cationic peptides that target the negatively charged lipid A component of lipopolysaccharides, disrupting the outer membrane and lysing the cell. Polymyxin resistance is conferred by inner-membrane enzymes, such as phosphoethanolamine transferases, which add positively charged phosphoethanolamine to lipid A. Here, we present the structure of MCR-1, a plasmid-encoded phosphoethanolamine transferase, in its liganded form. The phosphatidylethanolamine donor substrate is bound near the active site in the periplasmic domain, and lipid A is bound over 20 Å away, within the transmembrane region. Integrating structural, biochemical, and drug-resistance data with computational analyses, we propose a two-state model in which the periplasmic domain rotates to bring the active site to lipid A, near the preferential phosphate modification site for MCR-1. This enzymatic mechanism may be generally applicable to other phosphoform transferases with large, globular soluble domains.
Ex vivo evaluation of anti-migration forces of ureteral self-expanding metal stents with different flange designs
Electrical and antimicrobial studies of multifunctional ZrO2 doped borate glasses and glass ceramics
Abstract In this study, borate-based glass and glass–ceramics doped with varying concentrations of ZrO 2 were synthesized, followed by controlled heat treatment for crystallization. X-ray diffraction, density, Fourier-transform infrared spectroscopy, field emission scanning electron microscope, and dielectric relaxation spectroscopy were employed to characterize the prepared samples. XRD analysis confirmed the formation of the nanocrystalline ZrO 2 phase within the glass–ceramic matrix. The average crystallite size, determined by the Scherrer formula, fell within the nanometric range. DRS investigated the dielectric response of all samples over a wide frequency range (0.1 Hz–1 MHz) at 30 °C. It showed enhanced dielectric properties with increasing ZrO 2 content. Significantly increased permittivity while decreased loss tangent for glass and glass ceramics with higher ZrO 2 content. Furthermore, glass ceramic exhibited better dielectric properties than glass samples. For electrical properties, the optimal mol% suggested for Zr 4+ is 2 since it exhibited the highest permittivity (~ 23 at 1 MHz) and lowest loss tangent (~ 0.005) for glass and glass ceramics. The substitution of CaO by ZrO 2 increases both permittivity and AC conductivity while reducing the dielectric losses, confirming the enhancement of dielectric properties. Furthermore, the antimicrobial activity of the prepared samples was tested. The antimicrobial activity of the glass–ceramic results from the presence of ZrO 2 nanocrystals, which act in a similar manner to ZrO 2 nanoparticles. Cytotoxicity and long-term stability assays were carried out. The results display the effect of ZrO 2 on structure, crystallinity, and the noticed electrical and biological responses, making them promising materials for use in applications that require electrical functionality and biocompatibility.
Ultra-slow aging dynamics of glass and its application to geological dating
The use of angiotensin-converting enzyme inhibitors in hospitalized patients with COVID-19 is associated with a lower risk of mortality
CT-based intratumoral heterogeneity quantification fusing deep learning radiomics for predicting lymph node metastasis in early-stage lung adenocarcinoma: a multicenter study
Ultrablack wool textiles inspired by hierarchical avian structure
Abstract Wildlife often uses a combination of colors in their skin, scales, and feathers to both attract mates and avoid predators. Some animals express an extreme level of black color, called “ultrablack” with reflectance <0.5%. The various nano/microstructures that produce ultrablack have been studied and replicated synthetically. These synthetic ultrablack materials, however, use highly advanced and costly techniques, toxic substances, and lack the flexibility and biocompatibility that are often desired in real-world textile applications. Here we show that a conventional natural fabric can be transformed into an ultrablack one with a biocompatible dye and a surface modification to create nanofibrils. The ultrablack wool fabrics we report have an average total reflectance of 0.13% ( λ = 400–700 nm) and represent the darkest fabrics currently reported. Unlike commercially available ultrablack fabrics, the ultrablack wool developed in this study remains breathable and conformable. Furthermore, it exhibits wide-angle ultrablack performance, maintaining a symmetric (angle-independent) optical response across a 120° angular span. Environmental and mechanical tests also prove the material’s resilience, showing the retention of its natural fabric characteristics alongside its ultrablack properties. To demonstrate the manufacturability in the textile industry, we present multiple parameter sets for plasma etching to achieve the ultrablack effect.
Study on the loss of load-carrying capacity of thin-walled composite columns with closed cross-sections
Abstract The subject of the study was thin-walled composite columns with a closed cross-section. The aim of the research was to analyse the failure of compressed thin-walled sections with three cross-section shapes and four composite lay-ups. The study investigated the effects of column cross-section shape and composite lay-up on loss of load-carrying capacity. Experimental studies of the axial compression of thin-walled composite structures were conducted using interdisciplinary research methods, thereby determining, among other things, post-buckling equilibrium paths and modes of structural failure. In numerical simulations, the research was conducted using original finite element method models, including a failure model based on progressive failure analysis. The novelty of the present paper was the evaluation of the load capacity of profiles with closed sections, with particular attention to the influence of cross-section shape and composite-ply arrangement. The experimental and numerical results of the study were in quantitative and qualitative agreement.
Dynamic edge-caching through content popularity and crowd prediction for short video services
A 14-3-3 modulator of seed weight and quality for unlocking the yield potential of soybean
Towards a circular economy with application of salmon silage to a grassland in Chilean Patagonia
Integrating machine-learning and nanotechnology to quantify pH-modulated oxaliplatin release
Abstract The purpose of this work was to formulate and characterize pH-sensitive, surfactant-based nanomicelles for the targeted delivery of Oxaliplatin to breast cancer cells. A secondary aim was to utilize machine learning (ML) models to interpolate and dissect the sophisticated, pH-dependent drug release kinetics. Nanomicelles of Oxaliplatin were prepared by Pluronic F-127 through a thin-film hydration technique. The nanomicelles were characterized for size, morphology, encapsulation efficiency, and drug release profile in physiological (pH 7.4) and acidic, tumor-mimicking (pH 5.4) media. The MTT assay was used to test cytotoxicity against L929 normal fibroblasts and MCF-7 breast cancer cells. ML models (Random Forest, Gradient Boosting, SVR) were trained on experimental release data to anticipate crucial release phase changes using SHAP analysis. Prepared nanomicelles were monodisperse and spherical with hydrodynamic diameter 290.3 nm and encapsulation efficiency 40.2%. They had good pH-responsive release with cumulative release 77.5% and 43.5% at pH 5.4 and 7.4, respectively, in 96 h. Kinetic modeling revealed a shift from Fickian diffusion at pH 7.4 to anomalous transport at pH 5.4. ML models showed great interpolation performance (R² > 0.97), and SHAP analysis showed remarkable release transitions. The cytotoxicity assays were different from free Oxaliplatin with improved activity against MCF-7 cells and lower toxicity against L929 cells. Surfactant-based nanomicelles are an effective delivery platform for pH-directed delivery of Oxaliplatin to enhance its therapeutic index. Nanomedicine formulation design is enabled by ML through comprehensive release kinetics analysis.
Microprotein PLUM encoded by Lin28b uORF is a cytoplasmic determinant of pluripotency and embryonic development
Anatomical complexity in mandibular second molars: prevalence of C-shaped canals, radicular grooves, taurodontism, and radices molarum in Saudi population
Paramylon isolated from Euglena gracilis EOD-1 extends lifespan through activation of DAF-16-mediated antioxidant pathway via clec-196 in Caenorhabditis elegans
Abstract Paramylon (PM), an insoluble β-1,3-glucan produced by Euglena gracilis , reportedly possesses immunomodulatory and metabolic regulatory effects. However, its effect on longevity remains unclear. For this study, using Caenorhabditis elegans as a model, we evaluated lifespan-extending effects of PM and elucidated its underlying molecular mechanisms. Dietary PM supplementation prolonged the C. elegans lifespan significantly without affecting either growth or fertility, indicating the effects as independent of caloric restriction. Findings indicate that PM intake strongly upregulated clec-196 , an ortholog of the β-glucan receptor DECTIN-1. Also, RNA interference of clec-196 eliminated PM-induced lifespan extension, indicating clec-196 as necessary for the physiological response to PM. Moreover, PM supplementation increased expression of jnk-1 and daf-16 , which were suppressed when clec-196 was knocked down, suggesting that clec-196 functions upstream of the JNK-1/DAF-16 pathway. The lifespan-extending effect of PM was completely absent in loss-of-function mutant of daf-16 , underscoring its indispensable role. Furthermore, PM feeding activated the DAF-16-mediated antioxidant pathway, as evidenced by upregulation of antioxidant genes and by suppression of hydrogen peroxide accumulation. These findings suggest that PM might serve as a functional food ingredient exhibiting anti-aging potential.