Search Results (32,784)

To evaluate the runoff pollution characteristics of roofs in an arid region, this study focused on Yinchuan City, China. It analyzed the runoff properties of various roof materials, including tile, asphalt, and color steel plate. Five rainfall events were monitored during 2024, with samples collected manually at roof pipe outlets and analyzed for suspended solids (SS), chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP), and ammonia nitrogen (NH₃-N). The results indicated that the concentration of pollutants in runoff from these roofs decreased as rainfall duration increased. The event mean concentration (EMC) of TN and COD in runoff from all three roof materials exceeded the Class V surface water quality standards in China. The first flush of pollutants in roof runoff followed a descending order: SS > COD > TP > TN > NH₃-N. Cluster analysis of three rainfall parameters—dry period, precipitation, and rainfall intensity—revealed that dry period exerted the strongest influence on runoff quality, indicating that the overall quality of roof runoff was primarily influenced by the cumulative effects of atmospheric deposition, with rainwater scouring being the secondary factor. These findings provide critical insights for designing stormwater management strategies and rainwater harvesting systems in arid and semi-arid cities, emphasizing the need to prioritize first-flush control and consider local climatic conditions. Full article

Active packaging using edible coating could be an essential and sustainable alternative solution to preserve the properties of fruits and to prevent food loss and food waste. Chitosan, a linear polysaccharide obtained by deacetylation of chitin, has been widely used as an edible coating of fruits. Therefore, this study aimed to develop a chitosan-based edible coating incorporated with Aloe vera and beeswax. Edible coatings were formulated with the following proportions: (% V/W: chitosan: Aloe vera: beeswax) as F1 (chitosan 79.5%: Aloe vera extract 19.5%: beeswax 1%), F2 (chitosan 79.2%: Aloe vera extract 19.2%: beeswax 1.5%), and F3 (chitosan 79%: Aloe vera extract 19%: beeswax 2%). After characterization, films were applied to Musa paradisiaca (banana) and Diospyros kaki (persimmons) varieties: Hychia and Fuyu, respectively, of Khyber Pakhtunkhwa, Pakistan. The film containing a higher concentration of beeswax, F3, attained the lowest moisture content (22.12% ± 0.57). The edible coatings, especially (F3) treated fruits, improved significantly in the quality attributes of banana and persimmon as: % weight loss (95.11 ± 0.023, 158 ± 0.81), pH (5.3 ± 0.005, 5.67 ± 0.005), titratable acidity (0.521% ± 0.05, 0.692% ± 0.002), total antioxidant capacity (34.6%, 49.2%), decay incidence (30%, 45%). Chitosan and Aloe vera extract incorporated with a beeswax edible coating had a significant effect on all the studied characteristics and there was an increased shelf life for both M. paradisiaca and D. kaki. Our findings demonstrated that a coating enriched with Aloe vera extract and beeswax is an efficient bioformulation to improve shelf life, preserve the properties of fruit, and prevent food loss. Full article

Accurate assessment of nitrogen content in maize leaves is crucial for scientific fertilization and environmental protection in agricultural production. Traditional nutrient diagnosis methods are inefficient, costly, and destructive, while machine learning approaches based on handcrafted features rely heavily on manual design, leading to limited generalization ability and suboptimal prediction accuracy. To address these issues, this paper proposes a convolutional neural network model named SCBI-EfficientNetV2, which adopts EfficientNetV2-S as the backbone to overcome the limitations of manual feature engineering through automatic feature extraction. Furthermore, a Spatial and Channel Synergistic Attention (SCSA) module is introduced to enhance the modeling of critical regions and informative channels, and a Bidirectional Feature Pyramid Network (BiFPN) is incorporated to achieve effective multi-scale feature fusion, thereby improving the representation of hierarchical structural features in maize leaves. Experimental results show that SCBI-EfficientNetV2 achieves a coefficient of determination (R²) of 0.9417 on the test set, representing a 5.25% improvement over the baseline model and outperforming five classical deep learning approaches. In addition, the proposed model maintains high prediction accuracy with relatively low computational cost, demonstrating good adaptability for edge deployment. This study provides a feasible solution for non-destructive intelligent diagnosis of maize nutrition and offers technical support for precision fertilization and sustainable agricultural development. Full article

Novel porous geopolymer (IGP&SS), possessing mesoporous structure and a compressive strength of 9.40 MPa, was synthesized through alkali activation of double solid wastes such as iron tailings and steel slag. To overcome the high activation energy barrier of oxidants for refractory pollutant treatment, the IGP&SS was designed to efficiently activate peroxymonosulfate (PMS) under visible-light irradiation, generating reactive radicals for the rapid degradation of methylene blue (MB). The system achieved nearly complete removal within 30 min. To enhance MB removal, the effects of key factors including IGP&SS dosage, PMS dosage, initial MB concentration, temperature, and pH on the degradation process were systematically investigated. Quenching experiments revealed that several reactive oxygen species contributed to MB degradation, with the order of contribution being •OH > ¹O₂ > SO₄•⁻ > •O₂⁻. Mechanistic studies indicated that the efficient MB degradation was primarily attributed to the flexible Fe(II)/Fe(III) redox cycling in IGP&SS, which accelerated PMS activation and radical generation. X-ray photoelectron spectroscopy (XPS) analysis of the post-reaction catalyst confirmed its structural robustness, revealing a characteristic binding energy shift in the O 1s peak to 530.8 eV and a quantitative redistribution of iron species (Fe(III) content increasing from 40.4% to 57.0%). Given its outstanding performance, demonstrated stability, and eco-friendly preparation, IGP&SS holds great promise for PMS-based advanced oxidation processes in dye wastewater treatment, offering a sustainable approach for high-value utilization of iron tailings and steel slag while alleviating resource scarcity. Full article

This study presents a predictive method for the fatigue behavior of Ti-6Al-4V based on a crystal plasticity finite element (CPFE) model. A thermally activated constitutive model is calibrated using experimental cyclic stress–strain data. The calibrated model simulates the macroscopic cyclic response and grain-scale deformation heterogeneity. By analyzing the simulated micromechanical fields, a scalar fatigue indicator parameter (FIP) is defined based on the accumulated inelastic work. The predictive capability of this FIP is validated against experimental data at multiple stress levels, demonstrating its effectiveness for microstructure-sensitive fatigue assessment. Full article

The adsorption and desorption behavior of arsenic (As) in agricultural soils is a critical process controlling its migration, transformation, and bioavailability, with direct implications for food safety and environmental risk. Although black soil regions are major grain-producing areas in China, the roles of different soil microaggregate fractions and their components in As retention remain poorly understood. Therefore, batch equilibrium adsorption experiments were performed to study the adsorption and desorption behaviors of As(V) on the different microaggregates and to explore the effects of soil particle size, organic matter and iron oxide on the adsorption performance of As(V). The results show that as the concentration of As(V) increases, the adsorption capacity gradually reaches equilibrium, and the Freundlich equation fits the results well. The order of the As adsorption capacity of microaggregates of different particle sizes in black soil is as follows: (<0.002 mm) > 0.005–0.05 mm > 0.002–0.005 mm > 0.05–0.25 mm > 0.25–2 mm. The maximum adsorption capacity occurs in the microaggregates of the soil with the smallest particle size. The order of the As desorption capacity of microaggregates of each particle size is opposite to their adsorption capacity and inversely proportional to the content of each component in the soil. Removal of soil organic matter (SOM) and free iron oxide (Fe_d) significantly reduced the specific adsorption and immobilization capacity of black soil for As(V), while enhancing non-specific adsorption. This study elucidates the differential contributions of soil microaggregates and key components to As(V) retention and provides an experimental foundation for further research on the occurrence and migration mechanisms of As in black soil. Full article

Numerous studies have demonstrated that the brain and blood–brain barrier, which are sensitive targets for cell phone and microwave radiation, are damaged after exposure. Additionally, ginseng has been shown to play a role in preserving the integrity of the blood–brain barrier. In this study, we investigated the immunohistochemical, genetic and biochemical effects of electromagnetic field (EMF) on the blood–brain barrier (BBB) and the protective role of ginseng on these effects. The animals were randomly allocated into seven groups (eight in each group): group I: control, group II: sham, group III: ginseng, group IV: 2100 MHz EMF, group V: 2100 MHz EMF + ginseng, group VI: 2450 MHz EMF, group VII: 2450 MHz EMF + ginseng. EMF groups exposed to EMF, 1 h day⁻¹ for 30 days. Ginseng was administered 150 mg/kg/day for 30 days. As a result, it was determined immunohistochemically that EMF caused apoptosis in brain tissue. It was observed that cyclooxygenase-2 (COX-2) gene decreased and B-cell lymphoma/leukemia-2 gene (BCL-2)-associated X (BAX) protein increased in EMF groups, as well as apoptosis formation. On the other hand, it was concluded that ginseng decreased the harmful effects by increasing the expression of the COX-2 gene and decreasing the BAX protein in this process leading to apoptosis. Full article

Polystyrene (PS) is widely used yet highly flammable, and developing halogen-free flame retardants that ensure both high fire safety and mechanical performance remains a challenge. A green intumescent system comprising ammonium dihydrogen phosphate (ADP) and phytic acid–triethylenetetramine (PA–TETA) was incorporated into PS powder via sequential solution grinding and hot pressing. The optimal formulation, PS/10ADP/15PA–TETA, achieved a limiting oxygen index of 28.5% with a UL-94 V-0 rating, and reduced the peak heat release rate and total heat release by 73.8% and 46.2%, respectively, while retaining 78.4% of the tensile strength of neat PS. The ADP/PA–TETA system operates via a cooperative condensed-phase charring and gas-phase dilution mechanism, achieving superior flame retardancy in PS composites. This work provides an effective and eco-friendly strategy for fabricating high-performance PS composites with balanced flame retardancy and mechanical properties. Full article

With the advancement of SiC wafers toward 12 inches and innovations in laser cutting technology, new demands have emerged for SiC grinding techniques—namely, high efficiency, low loss, and low wear ratio. This paper investigates electrochemical-assisted grinding of SiC using a grinding wheel–SiC pair model system, examining the effects of electrolyte type, concentration, voltage, load, and rotational speed on wear behavior. Experimental results reveal that NaCl is the most effective electrolyte among the six candidates tested. In the NaCl system, wear behavior is strongly influenced by the interplay between voltage and rotational speed. At a constant voltage of 3 V, increasing the rotational speed to 600 rpm produces a wear area of 1911.93 μm², while at a higher voltage of 7 V with a lower speed of 200 rpm, the wear area reaches 1301.96 μm², indicating that optimal material removal requires synergistic matching of electrical and mechanical parameters. At 2 wt% NaCl, a sudden change in wear behavior occurs at 6–7 min, indicating a dynamic balance between oxide formation and mechanical removal. Rotational speed shows a turning point at 600 rpm, where the wear mechanism shifts significantly, marking the transition to a synergistically enhanced regime. EDS analysis confirms that Na₂SO₄ increases surface oxygen content by 54.4% compared to deionized water, demonstrating enhanced electrochemical oxidation. The optimal parameter window for synergistic removal is identified as 1–2 wt% NaCl, 5–7 V, 600 rpm, and 100–150 g. This study provides quantitative insights into the synergistic removal mechanism of SiC, offering a theoretical foundation for developing efficient, low-loss electrochemical grinding technologies. Full article

Long COVID is a complex condition characterized by persistent symptoms following SARS-CoV-2 infection. Understanding its biochemical mechanisms is essential for effective management and treatment strategies. Objective: This study investigated biochemical alterations associated with long COVID in unvaccinated individuals presenting symptoms persisting for more than six months, highlighting the prolonged nature of the condition and its systemic and neurological manifestations. A cross-sectional study was conducted with 60 unvaccinated patients at least six months post-COVID-19 infection. Serum biomarkers, including C-reactive protein (CRP), interleukin-6 (IL-6), N-terminal pro-brain natriuretic peptide (NT-proBNP), and irisin, were analyzed. Correlations between these biomarkers and persistent symptoms were assessed using statistical regression models. Elevated CRP levels were significantly associated with persistent respiratory and musculoskeletal symptoms, suggesting ongoing inflammation. Increased IL-6 levels correlated with fatigue and musculoskeletal complaints. NT-proBNP elevations were linked to cardiovascular manifestations, including dyspnea and chest pain. A positive correlation between irisin and persistent sensory impairments, such as anosmia and dysgeusia, indicates potential neuroinflammatory mechanisms. This study highlights that persistent inflammation plays a critical role in long-term (>6 months) post-COVID manifestations. Monitoring biomarkers such as CRP, IL-6, NT-proBNP, and irisin may enhance understanding and management of prolonged post-COVID conditions. Full article

Wellbore instability and sand production pose critical challenges in deep tight sandstone reservoirs, severely impairing wellbore integrity and reducing hydrocarbon recovery. This study introduces, for the first time, the combined finite–discrete element method (FDEM) to numerically simulate sand production under high in situ stress. The FDEM By seamlessly integrates continuum and discontinuum representations within a unified framework, enabling the simulation of the complete failure sequence—from matrix damage and fracture growth to granular flow. High-resolution numerical simulations are conducted to compare intact and naturally fractured formations, with a focus on the governing role of pre-existing geological discontinuities. Results show that in intact sandstone, stress concentration drives helical crack growth leading to a symmetrical V-shaped breakout, with a critical borehole pressure (CBHP) of 60.05 MPa required to prevent instability. In fractured rock, however, pre-existing fractures act as dominant weakness planes that distort the stress field and induce earlier, asymmetric failure, raising the CBHP to 64.05 MPa. A strong negative linear correlation is observed between reservoir pressure depletion and CBHP: a pore-pressure reduction of 23.75 MPa decreases the CBHP by 4.8–5.0 MPa. Notably, natural fractures amplify the destabilizing effect of depletion, raising the required CBHP by 4.0 MPa at initial reservoir pressure (95 MPa) and by 5.0 MPa under full depletion. Consequently, although fractured formations require a higher CBHP (64.05 MPa vs. 60.05 MPa), their safe operating window is effectively narrower. These findings advance the mechanistic understanding of fracture-controlled sand production and provide a validated numerical framework for determining safe production pressures in deep, fractured sandstone reservoirs. Full article

High-strength low-alloy (HSLA) steels in marine environments suffer from microbiologically influenced corrosion (MIC) and hydrogen-assisted degradation. This study investigates the synergistic effects of sulfate-reducing bacterial biofilms, mechanical stress, and seawater chemistry on HSLA AH36 steel using electrochemical, microstructural, and magnetic Barkhausen noise (MBN) monitoring. Under multiparametric exposure (80% yield strength tensile stress, Desulfovibrio vulgaris, 28 days), biotic samples exhibited sustained 1.88× corrosion acceleration despite 86% sulfate depletion. Magnetic Barkhausen noise RMS amplitude (MBN_RMS) peaked at day 7 (612 ± 38 mV/mm) at pit depths of only 20–50 μm, detecting subsurface hydrogen damage before macroscopic failure. Quantitative correlations (R² ≥ 0.99) between MBN_RMS and cumulative mass loss revealed distinctive linear relationships in abiotic conditions and nonlinear cubic polynomials in biotic conditions, providing a non-destructive signature diagnostic of hydrogen-assisted MIC. Directional anisotropy analysis (parallel vs. perpendicular fields) showed that hydrogen-induced damage produces isotropic magnetic signatures (anisotropy ratio: 1.27 → 1.15), enabling discrimination between hydrogen embrittlement and stress-controlled degradation. The integration of portable MBN measurements with electrochemical monitoring establishes a quantitative framework for real-time structural health assessment and predictive maintenance of HSLA steels in maritime applications. Full article

Respiratory viral infections such as influenza and SARS-CoV-2 induce complex immune responses characterized by dysregulated cytokine production, which may influence disease severity and lead to post-infection immunometabolic alterations. However, comparative data on local epithelial and systemic immune responses during acute infection and recovery remain limited. Objective: To evaluate the expression of IFN-γ, TNF-α, and interleukins IL-2, IL-4, IL-6, and IL-10 in nasopharyngeal epithelial cells from patients with influenza and SARS-CoV-2 infection, as well as in peripheral blood mononuclear cells (PBMCs) from individuals who recovered from COVID-19. Methods: A total of 120 participants were distributed into four groups (control, influenza, asymptomatic SARS-CoV-2 infection, and symptomatic COVID-19; n = 30 per group), in addition to 90 individuals who had recovered from COVID-19. COVID-19 and influenza diagnoses were established by the treating physician based on clinical presentation and confirmed by RT–qPCR. Cytokine gene expression was quantified by real-time PCR, and hematological and biochemical parameters were measured using automated analyzers. Results: The asymptomatic SARS-CoV-2 group showed significantly increased expression of IFN-γ (p = 0.0001), TNF-α (p = 0.0007), and IL-4 (p = 0.01). Individuals who recovered from COVID-19 exhibited elevated erythrocyte and leukocyte counts, along with increased glucose, glycated hemoglobin, triglycerides, and very-low-density lipoprotein levels, while no significant alterations in liver function markers were observed. Conclusions:Influenza and SARS-CoV-2 infections are associated with distinct epithelial cytokine expression profiles during acute infection, and COVID-19 recovery is characterized by persistent immunometabolic alterations, suggesting prolonged systemic effects beyond viral clearance. Full article

Background/Objectives: Tuberculosis and COVID-19 are two major infectious diseases with significant inflammatory and immunological impact on infected hosts and both conditions are independently associated with a prothrombotic state. However, evidence regarding their combined effect on in-hospital thrombotic risk remains limited. In this study, we aimed to explore whether patients with tuberculosis and COVID-19 coinfection are at a higher risk of developing thrombotic events during hospitalization than patients diagnosed with tuberculosis alone. Materials and Methods: We performed a retrospective, single-center cohort study, including adults hospitalized at the Pulmonology Clinic, Adult Tuberculosis ward of Mures County Clinical Hospital, between 2021 and 2023. Two groups were analyzed: patients with pulmonary tuberculosis who developed COVID-19 during hospitalization (n = 40) and patients with pulmonary tuberculosis without documented SARS-CoV-2 infection (n = 40). Demographic, clinical, laboratory, and imaging data were extracted from medical records. Padua and IMPROVE-DD scores were calculated retrospectively, a rapid mini-score was evaluated exploratorily. Comparisons between groups were performed using appropriate statistical tests and unadjusted odds ratios (ORs) with 95% confidence intervals (CIs) were reported. Given the limited number of events, an age-adjusted Firth penalized logistic regression model was used for multivariable analysis. Results: Thrombotic events occurred more frequently in the tuberculosis and COVID-19 co-infection group (22.5% vs. 10%), although statistical significance was not reached (p = 0.22; OR = 2.61). Patients with coinfection had significantly higher proportions of elevated Padua scores (55% vs. 20%, p = 0.002; OR = 4.88), while IMPROVE-DD showed values near the conventional threshold for statistical significance (37.5% vs. 17.5%, p = 0.07). D-dimer values did not reach statistical significance (p = 0.07) and platelet counts were significantly higher in patients with tuberculosis only (p = 0.001). Mortality did not differ significantly between groups (15% vs. 10%, p = 0.73). In age-adjusted multivariable analysis, tuberculosis and COVID-19 coinfection remained associated with higher odds of thrombotic events, with wide confidence intervals. Conclusions: Patients with concomitant tuberculosis and COVID-19 showed a higher thrombotic risk profile (Padua score) and numerically higher rates of in-hospital thrombotic events, without reaching statistical significance. Findings should be interpreted as exploratory and hypothesis-generating. Larger prospective studies with systematic imaging and multivariable adjustment are needed. Full article

Heavy metal contamination in coastal and ballast waters motivates the development of low-cost, environmentally compatible filtration media. This study investigates how 6 MeV electron-beam irradiation (0–100 Gy) modifies the surface electronic and chemical properties of quartz-rich Baltic Sea sands collected from four Latvian coastal locations (Riga, Salacgriva, Ventspils, and Liepaja), and how these modifications affect chromium removal from aqueous K₂CrO₄ solutions. Surface electronic behavior was evaluated by near-threshold photoelectron emission spectroscopy (PEES), including electron work function (EWF) and analysis of differentiated spectra, while irradiation-associated changes in near-surface chemistry were assessed by X-ray photoelectron spectroscopy (XPS). Filtration performance was quantified by UV–Vis absorbance of filtrates. Across all sands, EWF values remained within ~4.7–4.9 eV; however, irradiation effects were strongly site-dependent. Liepaja sand exhibited the most pronounced response, including an EWF increase at 40 Gy, a shift in the differentiated PEES peak toward higher photon energies at ≥40 Gy, and the largest integrated photoemission intensity across doses, consistent with an elevated relative photoemission response under identical acquisition and processing conditions. XPS trends for Liepaja were consistent with irradiation-driven modification of the Si–O environment, while other sites showed comparatively minor changes. Filtration results mirrored these observations: Liepaja sand demonstrated the clearest dose-dependent enhancement in chromium removal with a non-monotonic feature at 40 Gy, consistent with competing formation and transformation of oxygen-related surface-reactive centers. Overall, the results show that electron-beam irradiation can modestly enhance Cr(VI) removal by natural quartz sands, with the magnitude governed by site-specific near-surface electronic structure and its dose-dependent evolution. Full article