Search Results (19,542)

AlCrFeNi-based high-entropy alloys (HEAs) have attracted considerable interest owing to their adjustable phase constitution and attractive mechanical performance. In this study, AlCr_1.6Fe_xNi_(3.2−x)Si_0.2 HEAs (x = 1.0–2.0) were fabricated by vacuum arc melting to systematically evaluate the influence of the Fe/Ni ratio on phase evolution, microstructural characteristics, and mechanical behavior. The results indicate that, with increasing Fe content, the phase constitution gradually changes from BCC+B2+σ to BCC+B2. Correspondingly, the microstructure evolves from floral and cellular eutectic morphologies to branch-like BCC-rich regions with inter-branch/intercellular eutectic constituents. At the same time, the Vickers hardness decreases from 584.1 HV to 365.7 HV as the Fe content increases. Compression results show a gradual reduction in alloy strength, whereas the deformation ability is noticeably improved. Fracture surface analysis further reveals that the alloys with x ≤ 1.4 exhibit typical brittle fracture features, while those with x ≥ 1.6 display incomplete fracture and enhanced plastic deformation. These results clarify the relationship among Fe/Ni ratio, phase constitution, microstructural evolution, and mechanical properties in AlCrFeNiSi-based HEAs. Full article

Introduction: A genetic algorithm (GA)-based approach was designed to predict drug–drug interactions (DDIs) triggered by cytochrome P450 3A (CYP3A) inhibition or induction in horses. Methods: Area under the concentration-time curve ratios (AUCRs), obtained from published in vivo DDI studies in horses, were used to compute the following parameters: (1) the contribution ratio (CR), i.e., the fraction of the substrate dose metabolized via the CYP3A pathway, and (2) the interacting drug’s inhibitory potency or inducing efficacy (IR or IC, respectively). Results: AUCRs for 9 substrates, 12 inhibitors, and 1 inducer of equine CYP3A were predicted and validated with the developed method. More than 96% of predictions fell within the commonly accepted range of 50–200% of observed values. Conclusions: The proposed GA-based method may be a useful tool to estimate possible clinically relevant DDIs when co-administration of a CYP3A substrate and a CYP3A-interacting drug is anticipated. Full article

CRS type 1 (CRS-1) is defined as acute kidney injury (AKI) caused by acute decompensated heart failure (ADHF). HF is divided into three subtypes according to the value of ejection fraction (EF). HF with preserved ejection fraction (HFpEF) is an increasingly prevalent subtype of heart failure. A significant number of patients with HFpEF during episodes of acute decompensation (ADHFpEF) develop CRS-1. The objective of this narrative review is to summarize the data about the epidemiology, pathophysiological mechanisms, therapy, and prognostic impact of CRS-1 in patients with ADHFpEF. The most important pathophysiological mechanisms leading to the development of CRS-1 in these patients are hemodynamic disturbances and inflammation. Loop diuretics alone or in combination with other diuretics are the mainstay therapeutic option for treating congestion in patients with CRS-1. Introducing SGLT-2 inhibitors as soon as clinically possible has a positive impact on prognosis. CRS-1 is an independent predictor of a worse outcome in patients with ADHF, although this impact appears to be less associated in patients with HFpEF, than in patients with ADHF with reduced EF. Further studies are needed to better clarify pathophysiological mechanisms and develop treatments that improve cardiorenal outcomes in these patients. Full article

This research investigates the formation and behavior of sustainable crumb rubber-modified gypsum–cement–pozzolan (GCP) composites, with a view to their use in a broad concept for construction. GCP binders are gaining attention as a low-carbon replacement for Portland cement, and the addition of recycled rubber helps the achievement of circular economy goals and potentially increases durability. The present research evaluates the impact of crumb rubber (CR) on the mechanical strength, water absorption, dimensional stability, and freeze–thaw resistance of 3D-printed GCP-rubber composites. Composite blends of variable proportions of crumb rubber were prepared at constant binder ratios. Mechanical properties were defined by prism specimens (40 × 40 × 160 mm) by the flexural and compressive strengths, and deformation was determined by micrometers to measure longitudinal strain as a function of curing. Water absorption was determined prior to freeze–thaw cycling to define pore saturation. Durability was investigated using two approaches: (1) controlled freeze–thaw experiments on cube specimens, with XF1 grade performance achieved, and (2) ultrasonic pulse velocity (UPV) testing of specimens 3D-printed for assessing internal structural change after long-term frost exposure. Results showed that compressive strength decreased moderately (10–20%) with increasing rubber content from 17% up to 50%, while flexural strength improved up to 15%, showing the elastomeric action of CR. Water absorption was reduced by 5–8% in the rubber-modified blends due to the hydrophobic character of rubber. Deformation tests also confirmed minimum length variation (<0.02%) during curing. Freeze–thaw durability was enormously improved, and test specimens retained more than 95% of initial strength. UPV measurements detected only a relatively modest velocity drop (~50 m/s) after 36 days cycling with subsequent stabilization up to 200 days, demonstrating long-term internal structure with minimal progressive damage. In summary, the findings demonstrate that GCP composites with crumb rubber incorporated are printable, dimensionally stable, and capable of freeze–thaw degradation resistance. Despite a moderate loss of compressive strength, the balance of introduced durability and sustainability suggests their competence as viable materials for additive manufacturing in construction. Full article

The main aim of this study is to investigate the microstructure and microhardness of Wire Arc Additive Manufactured (WAAM) samples produced under different layer deposition strategies and corresponding interlayer temperature conditions. Experimental samples were produced using the WAAM process with X45CrSi9-3 steel. During the experiments, both the number of layers and the thermal conditions (heating and cooling) were systematically varied. This was achieved by fabricating samples consisting of five layers with three beads per layer. The layer deposition procedure was implemented in two different ways: (i) with a waiting period after each layer to allow cooling to room temperature, and (ii) without such a waiting period. Thermal cycles at selected locations within the samples were calculated using simulation modeling. By combining these thermal cycles with the continuous cooling transformation (CCT) diagram, the expected microstructures in the vicinity of these locations were determined. These predictions were supplemented by microstructural analysis and hardness measurements. Particular emphasis was placed on the influence of interlayer temperature and repeated heating and cooling cycles. The analyses enabled the identification of process parameters that facilitate control over microstructure, microhardness, and property gradients. It can be concluded that the interlayer holding time provides an effective means of controlling the microstructure of the workpiece, ranging from predominantly austenitic to predominantly martensitic. Depending on the thermal cycles, the measured microhardness varied within the range of 360–900 HV. Metallographic examination revealed a wide spectrum of non-equilibrium microstructures, including martensite with varying degrees of tempering, retained austenite, pearlite, and bainite. The application of a thermal model to the conducted experiments, combined with the CCT diagram, indicated that the expected microstructures consist predominantly of martensite with varying degrees of tempering, retained austenite, carbides, and, in some cases, up to 5% pearlite. Full article

Air quality in the San Joaquin Valley (SJV) ranks among the worst in the US. Exposures to traffic-related air pollutants have been associated with pediatric health complications, and few studies have investigated respiratory complications in relation to short-term exposures to PM less than 2.5 microns in diameter (PM_2.5) in the SJV. We used Bayesian Poisson spatiotemporal conditional autoregressive models to analyze the association between PM_2.5 and pediatric respiratory emergency department (ED) visits in Fresno County, California. Additional analyses stratified respiratory outcomes by sex and age group. Weekly ambient PM_2.5 levels were estimated for each zip code using community science and regulatory air monitors. Weekly residential zip code counts of respiratory ED visits were provided by Fresno County Department of Public Health and Valley Children’s Hospital from 2 April 2022 to 31 December 2024. A ten-fold increase in PM_2.5 was associated with increased asthma ED visits among females (Relative Risk (RR):1.15; 95% Credible Interval (CrI):1.01, 1.32) and children aged 0 to 4 (RR:1.18; 95% CrI:1.03, 1.34) and other chronic respiratory conditions among males (RR:1.93; 95% CrI:1.19, 3.16) and ages 10 to 14 (RR:2.90; 95% CrI:1.32, 6.30). Findings suggest that efforts to better assess and reduce pollution exposures will improve public health in the SJV. Full article

This article presents results on four-dimensional CR submanifolds of the homogeneous nearly Kähler product manifold ${\mathbb{S}}^3\times {\mathbb{S}}^3$. In the research of CR submanifolds of ${\mathbb{S}}^3\times {\mathbb{S}}^3$, the most important role in the classification is played by the action of the almost product structure P. Here, the investigation of the action of the almost product structure on the tangent bundle of four-dimensional CR submanifolds of ${\mathbb{S}}^3\times {\mathbb{S}}^3$ is extended. Classifications are obtained for certain types of submanifolds whose almost complex distribution is almost product invariant, such as the class characterized by a special type of angle functions, as well as those whose tangent bundle is almost product invariant. The previously mentioned classes of four-dimensional CR submanifolds lead to the classification of those submanifolds that are locally usual product manifolds of Lagrangian submanifolds of ${\mathbb{S}}^3\times {\mathbb{S}}^3$ and curves. Full article

The industrial extraction of chitin from shrimp shell waste conventionally employs corrosive chemical treatments, which pose significant environmental hazards and compromise polymer integrity. This study introduces a sustainable and highly efficient microbial biorefining strategy for the recovery of α-chitin from Litopenaeus vannamei shells, utilizing a sequential fermentation framework. Two potent strains—Bacillus haynesii MGPUMGRI, known for its proteolytic capabilities, and Lactobacillus delbrueckii MGPUMGRI, which produces lactic acid—were isolated and optimized. A notable technical achievement was the purification of an approximately 40 kDa extracellular alkaline protease from B. haynesii, which demonstrated optimal activity at pH 9.0 and 37 °C. Under optimized conditions, the sequential process—emphasizing enzymatic deproteinization (72.30 ± 1.56%) followed by lactic acid-mediated demineralization (84.98 ± 1.96%)—achieved a high-purity chitin recovery of 61.33 ± 1.06%. Comprehensive characterization using SEM-EDX, FTIR, and XRD confirmed the successful preservation of the α-chitin polymorphic structure, which exhibited a fragmented fibrillar morphology and a crystallinity index (CrI) of 60.51%. These findings indicate that this dual-strain bioprocess offers a scalable and environmentally friendly alternative for the valorization of seafood waste into high-quality biogenic polymers, while minimizing the ecological impact of chitin production. Full article

CrN/DLC composited coatings were deposited on 431 stainless steel, and their structure was analyzed, with particular emphasis on the influence of CrN content on the coating properties. X-ray photoelectron spectroscopy (XPS), nanoindentation testing, scratch testing, and reciprocating tribometry were employed to characterize the chemical composition, mechanical properties, adhesion strength, and tribological performance of the coatings, respectively. Structural analysis indicates that when the ratio of CrN/Cr₂N is relatively low (<1), a high content of chromium dinitride (Cr₂N) is formed in the interlayers, resulting in a porous and loose coating structure. When the ratio achieves 1:1, an optimal balance, with the CrN content reaching a maximum of 21.04% and the Cr₂N content decreasing to a minimum of 20.68%, the densification degree of the coatings is increased, the coating adhesion strength is improved to 11.87 N. Meanwhile, the enhanced formation of the CrN phase improves the hardness to 12.27 GPa. Tribological test results demonstrate that when the ratio is approximately 1:1, the coating exhibits the lowest friction coefficients under dry sliding, deionized water, and artificial seawater conditions (0.0932, 0.1409, and 0.1021, respectively), as well as the minimum wear rates. With the decrease in CrN content of the coatings, the interfacial mismatch degree of the coatings is aggravated, which leads to not only more interfacial defects but also a relatively loose structure, as well as a decrease in the bonding strength (6.81 N), hardness (5.22 GPa), and deformation resistance. Therefore, an excessive Cr₂N phase may degrade the hardness-to-elastic modulus ratio (H/E) of the coatings by increasing interfacial mismatch and reducing structural compactness. Full article

The Shymkent–Saryagash–Abay (A-15) international highway is a major Kazakhstan–Uzbekistan freight corridor that runs through the irrigated horticultural belt of the Turkestan Region in South Kazakhstan, where adjacent fields supply vegetables and cucurbits to the regional market. Composite soil samples (n = 18) were taken at six distances (2–300 m) from the road edge across three locations during 2022–2023, along with edible fruits of tomato, cucumber, watermelon, and melon (n = 12) from the adjoining fields. Pb, Zn, and Cd were measured via flame atomic absorption spectrometry after HNO₃/H₂O₂ digestion. Soil concentrations decreased sharply with distance (Pb: 26.3 → 5.98 mg kg⁻¹; Zn: 21.29 → 4.16; Cd: 0.47 → 0.01 mg kg⁻¹), exceeding the national soil MPCs by 1.5–3 times within 2–10 m. Pb and Zn exceeded the Kazakhstani food-safety MPCs in all four crops, and Cd in three of four (tomato, cucumber, and melon). Transfer factors followed the order of Cd (2.90–4.40) > Zn (1.99–3.00) > Pb (0.16–0.30), and the Cd geo-accumulation index ranged from 1.05 to 1.65 at 2–5 m. Adult dietary risk was acceptable (HI = 0.029–0.052; CR < 1.7 × 10⁻⁶), yet food-safety exceedances support a precautionary sanitary buffer and combined soil-and-crop monitoring along the corridor. Full article

Caloric restriction (CR) is known to activate a broad spectrum of cytoprotective signaling pathways and enhance tissue tolerance to various stressors, including those associated with the cytotoxic effects of pharmaceutical agents. Nephrotoxic drugs, such as aminoglycoside antibiotics, remain a major clinical concern due to their frequent use and potential to cause acute kidney injury (AKI), for which effective preventive strategies are still limited. In this study, we investigated whether CR applied for 5 weeks (4-week pretreatment + 1-week concurrent with AKI induction) can alleviate AKI triggered by the antibiotic gentamicin, with a focus on evaluating changes in antioxidant-related parameters and autophagy-associated signaling during CR-mediated nephroprotection. CR’s nephroprotective effects were evaluated using diagnostic assays, Western blotting, and histological analysis. Additionally, oxidative stress markers and mitochondrial integrity were assessed to analyze the impact of CR on antioxidant-related pathways. CR significantly improved renal function and structure, with reduced kidney injury markers (KIM-1, NGAL) and alleviated histological damage. Critically, CR mitigated oxidative stress, evidenced by decreased thiobarbituric acid reactive substances (TBARS) and protein carbonylation, as well as increased levels of the reduced form of glutathione and activity of glutathione peroxidase (GPx). A lowered Bcl-X_L/X_S ratio was consistent with reduced apoptotic signaling, while reduced leukocyte infiltration reflected attenuated renal inflammation. Additionally, a reduction in mitochondrial DNA (mtDNA) lesions suggested that CR was associated with modulation of mitochondrial and metabolism-related pathways, with concurrent improvements in mitochondrial stability. Our findings demonstrate that CR attenuated gentamicin-induced AKI and was associated with changes in antioxidant-related parameters, reduced mtDNA damage, a decrease in inflammatory cell infiltration, and modulation of autophagy-related signaling. Full article

Tetrastigma hemsleyanum Diels et Gilg is a high-value edible and medicinal homologous plant, routinely grown under conventional field or greenhouse production systems across Asia. However, mislabeling of conventional products as the rarer (and more expensive) wild version may occur for financial gain. In this study, stable isotopes (δ¹³C, δ¹⁵N, δ²H, and δ¹⁸O) and metal contents (Cr, Cu, Ni, As, Cd, Pb) were used to characterize plant tissues (tuber root, stem, leaf) and corresponding soils originating from simulated-wild-cultivated (WC) and greenhouse-cultivated (GC) pot trials using the same soil. Carbon and nitrogen isotopes served as key indicators for distinguishing GC and WC products. Specifically, δ¹³C values of GC plant tissues were 1.4 to 2.4‰ more positive than those of WC plant tissues (p < 0.05), and δ¹⁵N values in GC tissues were 2.7 to 4.6‰ more positive than δ¹⁵N in WC tissues (p < 0.01). Lower δ¹⁵N values observed in WC products indicate slower nitrogen turnover compared with GC products. Soil metal concentrations had significant differences between the two cultivation systems, but only limited effects on metal bioconcentration factors (BCFs) and translocation factors (TFs) in T. hemsleyanum tissues. Pb and Cd concentrations in root tissues had large differences between cultivation systems, and carbon dynamics in GC plants were more negatively affected by Pb levels in soils. These findings provide the first investigation of T. hemsleyanum grown under different cultivation practices and establish a scientific basis for distinguishing other wild or simulated-wild labeled food and medicinal plant products from conventionally grown products in future studies. Full article

The modernization of global energy infrastructure within the Industry 5.0 framework requires the use of high-strength steels and reliable joining technologies to ensure safe, sustainable pipeline transport. This study focuses on the analysis of heterogeneous welded joints formed between high-strength alloy steel (34KhN2MA/EN 34CrNiMo6) and an austenitic welded seam (ER 307). While austenitic welds mitigate the risk of cold cracking, they introduce significant structural and mechanical heterogeneity. To address this, the research proposes and validates a material homogeneity criterion (MHC) derived from the LM-hardness methodology. By analyzing the statistical dispersion of macrohardness (HRC) through indicators such as the Weibull homogeneity coefficient (m) and the coefficient of variation (ν), the study establishes a quantitative approach to assess material degradation and structural uniformity across key weld zones. Results demonstrate that macrohardness profiling effectively distinguishes between structurally heterogeneous regions near the weld axis characterized by low homogeneity coefficients (m = 4.04 < 10, A_m = 0.742 < 0.878), elevated variability (ν = 29.68% > 11.6%), and high technological damageability (D = 0.92 > 0.81, j_D = 11.87 > 4.38) with pronounced step-like variation in macrohardness (HRC ∈ [12.6; 47]), on the one hand, and stabilized homogeneous zones in the base material, where m = 24.89 > 10, A_m = 0.947 > 0.878, ν = 4.39% < 11.6%, D = 0.52 ⟶ 0, j_D = 1.09 ⟶ 0, and characteristic range of HRC = 47–55, on the other hand. This methodology provides a robust, quasi-non-destructive tool for enhancing predictive maintenance, digital twins, and the overall integrity management of “smart” pipeline systems. Full article

Coral reefs are among the most important and vulnerable marine ecosystems worldwide. AI-powered underwater visual monitoring has become essential for effective reef conservation, yet current methods still face severe limitations: spectral ambiguity caused by underwater turbidity, fine-grained confusion in early coral health assessment, and discrete forecasting models that cannot represent continuous ecological degradation dynamics. To address these issues, we propose Spectral-YOLOv13, a dual-domain vision-Mamba sensing framework for high-precision coral health evaluation and continuous ecological forecasting. The framework incorporates three novel components: a Wavelet-Integrated Omni-Neck (WIO-Neck) to perform multi-scale spectral filtering and suppress turbidity-induced noise; a Contrastive Prototype Head (CP-Head) to enhance discriminability between visually similar health states; and a Bio-Mamba Predictor based on state-space models to capture long-term continuous health trajectories. Extensive experiments on the CR-Mix++ dataset demonstrate that Spectral-YOLOv13 achieves 53.8% mAP with strong robustness in turbid underwater environments. It reduces four-week forecasting error by 26.8% and maintains real-time inference speed at 112 FPS. This work provides a reliable and high-performance vision framework for practical underwater coral reef monitoring and proactive conservation management. Full article

Tribocorrosion is one of the main degradation mechanisms affecting metallic components exposed simultaneously to mechanical wear and electrochemical corrosion. In this work, the influence of the Nb/Ti ratio on the tribocorrosion behavior of Fe–Cr–Mo–Nb–Ti multicomponent alloys produced by vacuum arc melting was investigated. The alloys were designed through systematic variations in the relative contents of niobium and titanium to assess their effect on electrochemical stability, wear resistance, and surface degradation. Electrochemical behavior was evaluated by potentiodynamic polarization in a 3.5 wt.% NaCl solution, while tribological and tribocorrosion tests were conducted using a ball-on-disk configuration under controlled conditions. Post-test surface analysis was performed using stereomicroscopy combined with digital image processing, enabling three-dimensional topographical reconstruction of the wear tracks and extraction of quantitative parameters including groove depth, pile-up height, wear track width, and surface roughness. The results demonstrate that the Nb/Ti ratio significantly influences both electrochemical and tribological responses. The alloy with the highest Nb/Ti ratio exhibited the best overall performance, showing the lowest corrosion current density (5.37 × 10⁻⁸ A/cm²) under static conditions and the lowest wear rate (1.32 mm³/mm²·year), together with the least severe surface degradation, characterized by a groove depth of approximately 7.8 µm and minimal pile-up formation. A progressive deterioration in performance was observed as the Nb/Ti ratio decreased, with the lowest-ratio compositions presenting higher wear severity and surface instability. The AISI 316L reference material exhibited intermediate performance across all evaluated parameters. Overall, increasing the Nb/Ti ratio enhances passive film stability, reduces plastic deformation, and mitigates material removal under tribocorrosion conditions. The incorporation of three-dimensional surface analysis provides a more robust evaluation of wear mechanisms, supporting the design of multicomponent alloys with improved resistance to combined mechanical and electrochemical degradation in aggressive environments. Full article