Search Results (15,110)

In a high-mountain gorge region, landslide hazards pose a serious threat to the upper Minjiang River, located at the eastern edge of the Tibetan Plateau. To map susceptibility in the upper Minjiang River basin, this study used a Random Forest model in conjunction with slope unit subdivisions. First, a landslide inventory containing 3785 landslides was established using human–machine interactive interpretation techniques. After a multicollinearity analysis, 11 key conditioning factors were selected to construct a spatial database, including elevation, slope, aspect, curvature, topographic wetness index, stream power index, distance to fault, peak ground acceleration, distance to road, vegetation index, and rainfall. The r.slopeunits algorithm was implemented to partition the study area into discrete slope units. The ideal parameter combination for slope units was determined through integrating the normalized slope aspect standard deviation and Moran’s I using an equal-weight scheme. Ultimately, 30,513 slope units were delineated in the upper Minjiang River. The random forest model trained on these ideal slope units was validated using a 70/30 split of landslide and non-landslide samples. In receiver operating characteristic (ROC) curve analysis, the model demonstrated excellent performance, with an area under the curve (AUC) of 0.852. The results indicate that small-scale landslides dominate the inventory in terms of frequency. Despite accounting for only 30% of the study area, the Very High and High susceptibility zones exhibit considerable degree of spatial overlap with current landslide clusters. Furthermore, shapley additive explanations (SHAP) explanatory metrics indicate that the random forest model’s predictive behavior is primarily influenced by terrain elevation, precipitation patterns, and proximity to transportation networks. Full article

This in vitro study evaluated the effect of irrigation on different polishing protocols and their influence on the surface roughness, microhardness, and mass of resin composites. Three resin composites (Admira^® Fusion, Filtek Supreme™ XTE, and Ceram.X Spectra™ STHV) were polished using four systems (Sof-Lex™, DIATECH^® ShapeGuard, Astropol^®, and Enhance™/PoGo™) under wet and dry conditions. Eight test groups were established for each resin composite (n = 10 per group). Vickers microhardness, surface roughness (R_a), and specimen mass were measured before and after polishing with one of the four systems, applied either with or without irrigation. For Admira^® Fusion polished with Sof-Lex^™, R_a values were lower without irrigation (p = 0.048), whereas Filtek Supreme^™ XTE and Ceram.X Spectra^™ STHV polished with the Enhance^™/PoGo^™ system showed lower R_a values when irrigation was used (p = 0.010 and p = 0.004, respectively). Sof-Lex^™ and DIATECH^® ShapeGuard produced the highest microhardness values for both Admira^® Fusion and Filtek Supreme^™ XTE. Moreover, specimens of Admira^® Fusion and Ceram.X Spectra^™ STHV polished with DIATECH^® ShapeGuard exhibited higher microhardness under irrigation (p = 0.048 and p = 0.027, respectively). Overall, polishing resulted in measurable material removal, reflected by a reduction in specimen mass, and in an increase in microhardness. Wet polishing generally increased microhardness, although the effect varied depending on the polishing system and resin composite. Clinicians should therefore consider both the resin composite and the polishing system when deciding whether to use irrigation, as appropriate irrigation control may help optimize the surface smoothness and microhardness of resin composite restorations. Conference Presentation: Preliminary data from this study were previously presented as an oral communication at the 32nd Portuguese Dental Association Annual Meeting. This manuscript represents a substantially expanded and revised version, developed as a full research article. Full article

Dopamine (DA) is a crucial catecholamine neurotransmitter, and its abnormal levels are closely associated with neurological disorders such as Parkinson’s disease. Electrochemical sensing technology offers a rapid and cost-effective platform for DA detection; however, it often suffers from interference from coexisting biomolecules such as ascorbic acid (AA) and uric acid (UA). In this study, we report a novel electrochemical biosensor based on PdMo bimetallene, a nanomaterial synthesized via a facile wet-chemical approach, aiming to enhance the detection performance and selectivity for DA. PdMo bimetallene is a highly curved, atomically thin two-dimensional nanosheet featuring abundant strained sites and a high density of active centers, enabling the selective and sensitive detection of DA. The results demonstrate that the as-prepared PdMo bimetallene-modified glassy carbon electrode (GCE) exhibits excellent electrocatalytic activity toward the oxidation of DA. The sensor displays a good linear response over the concentration range from 10 nM to 200 µM, with an ultrahigh sensitivity of 80 µA·µM⁻¹ cm⁻² and a low detection limit of 0.14 µM (S/N = 3). Owing to the synergistic electronic effect between Pd and Mo, the high density of exposed active sites, and the unique strained lattice structure of the bimetallene, the sensor enables accurate determination of DA concentrations even in the presence of interfering species such as AA and UA. In summary, the successfully fabricated PdMo bimetallene-based sensor offers the advantages of low cost, facile synthesis, a wide linear range, and high sensitivity, positioning it as a promising candidate for neurotransmitter detection applications. Full article

Dust concentration control in coal-fired power plants is challenged by large time delays and various disturbances, particularly in dry electrostatic precipitator-wet flue gas desulfurization (DESP-WFGD) processes, where the inner-loop dynamics are slower than those of the outer loop, limiting the effectiveness of conventional cascade tuning methods. This paper proposes a compensation-based simultaneous tuning method for cascade proportional-integral-derivative (PID)-PID control systems. The cascade structure is transformed into an equivalent single-loop system, allowing the outer-loop controller to reshape the equivalent plant dynamics. An equivalent controller is then designed using the simple internal model control method, from which the inner-loop controller is derived. Controller parameters are iteratively refined based on maximum sensitivity, overshoot, and integral absolute error. A feedforward controller is further introduced to reject measurable outer-loop disturbances. Simulation results under nominal, uncertain, and noisy conditions show that the proposed method achieves zero overshoot, improved robustness, and smoother control action compared with conventional separate tuning and Lee’s simultaneous tuning method. The proposed approach provides an effective and practical solution for dust concentration control in DESP-WFGD processes, and is extendable to industrial cascade systems with similar dynamic characteristics. Full article

The characteristics of two-phase flow in heterogeneous shale porous structures are of critical importance for oil and gas extraction and for evaluating the efficiency of underground resource recovery and carbon sequestration. However, although non-isothermal two-phase flow has been investigated in previous studies, systematic research on non-isothermal CO₂–crude oil displacement in heterogeneous shale porous structures remains relatively scarce. In this study, a multi-phase simulator was employed to simulate non-isothermal CO₂–crude oil displacement in heterogeneous porous structures, and the effects of injection rate, injection temperature, and wettability on two-phase flow characteristics in heterogeneous porous media were systematically analyzed. The results indicate that changes in the viscosity ratio between the displacing and displaced phases—induced by heat transfer—may be a key factor governing immiscible two-phase interfacial dynamics and flow behavior in heterogeneous porous structures. Injection temperature exerts a significant influence on both the main flow channels and local flow pathways within the porous structure; increasing the injection temperature of the displacing phase can effectively enhance displacement efficiency, with the steady-state CO₂ saturation increasing from 43.15% to 50.62% as the injection temperature increased from 293.15 K to 363.15 K. In addition, increasing the injection rate improves CO₂ sweep efficiency, with the steady-state CO₂ saturation increasing from 45.35% to 55.98% as the injection rate increased from 50 to 250 μm/s; however, excessively high injection rates lead to non-piston-like displacement and premature fluid breakthrough, and the CO₂ saturation decreased to 49.81% at 350 μm/s. Under strongly water-wet conditions, the CO₂ saturation after displacement stabilization is higher. Full article

The corrosion behavior of high-entropy alloys under cyclic wet–dry conditions simulating the salt-lake atmosphere was investigated. The composition, morphology, and electrochemical properties of the corrosion products formed on the alloy surface after corrosion were systematically analyzed. The results show that in a chloride-containing environment with alternating temperature and humidity, the Cr-containing oxide passive film formed on the alloy surface effectively inhibits the corrosion process in the early stages. In addition, electrochemical results show that the charge transfer resistance in the MgCl₂ system reaches 4.96 × 10⁵ Ω·cm² at prolonged exposure, which is significantly higher than that in the NaCl system, indicating a lower corrosion rate. However, over time, the passive film undergoes localized rupture due to chloride ion attack and stress, leading to pitting corrosion and expansion toward the substrate. This study reveals the corrosion mechanism of high-entropy alloys in high-altitude salt-lake atmospheric environments and provides crucial insights for material design and performance optimization for their engineering applications in salt-lake scenarios. Full article

Despite its significant water-saving potential, the adoption of alternate wetting and drying (AWD) irrigation remains limited due to infrastructure constraints and intensive manual monitoring requirements. An automated precision irrigation system was developed and tested at the Bangladesh Rice Research Institute research farm in Gazipur, Bangladesh. The system combined ultrasonic water-level sensors, capacitive soil moisture sensors, an Arduino-based microcontroller, a GSM communication module, and solar-powered automatic control gates. Field performance was evaluated following a Randomized Complete Block Design (RCBD) under four irrigation treatments: IRRISAT, IRRI35, IRRI25, and continuous flooding (CF). The first three irrigation treatments were operated using scheduled daily decision windows, in which irrigation actions were automatically triggered based on predefined schedules and sensor threshold values. In IRRISAT, irrigation started when soil moisture dropped slightly below saturation and stopped at a ponding depth of 5 cm, while IRRI35 and IRRI25 were triggered at volumetric soil water contents of 35% and 25%, respectively, with the same upper cutoff of 5 cm ponding depth; CF served as the control. The IRRI35 treatment achieved a high grain yield (7.76 t ha⁻¹) while reducing water use by 28% and energy consumption by 37% compared to CF. Water use efficiency was considerably higher under IRRI35 (9.4 kg ha⁻¹ mm⁻¹) than under CF (6.7 kg ha⁻¹ mm⁻¹). The automated system proved to be reliable and precise in scheduled irrigation control, significantly reducing water use and labor requirements. The findings suggest that large-scale adoption of the system under real-world cultivation conditions could reduce irrigation energy needs and contribute to sustainable water governance in rice production. Full article

An experimental investigation was conducted to examine the resistance to sulfate attack and chloride ion diffusion of concrete incorporating multiple industrial wastes (MIWC), including limestone powder (LP), tailings sand, and silica fume (SF). The degradation mechanisms of the MIWC under coupled sulfate wet‒dry cycles and chloride ion penetration are systematically revealed. Nine concrete mixtures were designed with variable water-to-binder (w/b) ratios, LP contents, SF dosages, and tailings sand/machine-made sand ratios. The results indicate that reducing the w/b ratio significantly enhances resistance to sulfate attack and chloride penetration. A moderate LP dosage optimizes pore structure and improves long-term sulfate resistance, whereas SF effectively refines the pore matrix and reduces the chloride diffusion coefficient. The coupled action of chloride and sulfate accelerates early-stage pore filling by corrosion products but promotes later-stage cracking because of expansive erosion products. A modified sulfate damage model and a multifactor coupled chloride diffusion model are established, which consider damage evolution, chloride binding, and time-dependent diffusivity. The predicted service life of the MIWC under marine exposure is in reasonable agreement with the experimental trends. This work provides a theoretical basis for durable design and industrial waste utilization in marine concrete structures. Full article

Quantifying glacier contributions to river discharge is challenging because many land surface models (LSMs) lack glacier processes, whereas standalone glacier models are often disconnected from catchment hydrology. Here we develop the Conjunctive Surface–Subsurface Process model version 2-glacier coupled model (CSSPv2-GLC), and evaluate it over the Three-River Headwaters Region (TRHR) at 3 km during 1979–2017. The glacier coupling raises Nash–Sutcliffe Efficiency for monthly streamflow simulation at Tuotuohe station from 0.63 to 0.79 during calibration and from 0.61 to 0.76 during validation. CSSPv2-GLC reduces glacier surface temperature error to 1.85 K, compared with 3.09 K for the CSSPv2. Glacier meltwater contributions to total discharge reached 11.5% in July and 10.8% in August in the Yangtze headwaters. In contrast, the Lancang and Yellow headwaters contributed up to 4.5% and 1.8% in August. Dry-year contributions are 2–3 times higher than wet-year values, indicating a transient drought-buffering effect. These results demonstrate the value of integrating physically explicit glacier processes into land surface modeling frameworks for water resource assessment in glacierized headwater regions, and highlight the necessity of accounting for non-stationary glacier contributions to streamflow. Full article

The Aedes aegypti mosquito exhibits a critical behavioral adaptation through its oviposition strategy, laying eggs in dry and wet environments just above the water level, allowing eggs to resist desiccation and hatch only when submerged by rain. To investigate this mechanism, we developed a nonlinear dynamic model incorporating climate-driven parameters affecting egg hatching and adult emergence. Theoretical analysis revealed an imperfect pitchfork bifurcation giving rise to a phenomenon we term basin-mediated hysteresis. Unlike classical hysteresis, which relies on coexisting stable states, this mechanism results from the progressive collapse of the extinction basin boundary. As the control parameter approaches its critical value, the basin of attraction of the trivial equilibrium shrinks. Once the population establishes itself above the threshold, returning the parameter below unity does not restore extinction, leading to an irreversible transition governing population persistence. The model was validated using field data from mosquito traps in a Brazilian city, showing strong agreement with observed seasonal patterns of female captures. Parameters were optimized using the Differential Evolution algorithm, yielding high correlation between model and field data. The results demonstrate that the dual oviposition strategy underlies population persistence and seasonal peaks, providing information for planning interventions amid global arbovirus expansion. Full article

Coastal ecosystems, particularly semi-enclosed gulfs, are increasing anthropogenic pressures from urbanization and industrialization with profound impacts on biodiversity maintenance, energy transfer, and biogeochemical cycling. However, how metazoan communities—key components of marine food webs—respond to spatiotemporal variability and human disturbance remains insufficiently understood. This study applied eDNA metabarcoding targeting the mitochondrial COI gene to investigate metazoan communities across 68 stations in the Beibu Gulf, spanning bay, coastal, and island regions, during wet and dry seasons. In total, 878 metazoan ASVs from 13 phyla were detected. Arthropoda dominated both seasons (wet: 85%; dry: 55%), whereas Chordata increased during the dry season (wet: 0.16%; dry: 37%). At the α-diversity level, diversity peaked in the bay region during the dry season and shifted toward the coastal region during the wet season. At the β-diversity level, community composition differed significantly between seasons and spatial regions, with seasonal variation exerting a stronger influence than spatial differentiation. Co-occurrence networks revealed higher complexity during the dry season. β-diversity was overwhelmingly driven by species turnover (94.4%). The island region exhibited the highest community uniqueness, while the human-impacted bay region showed reduced distinctiveness. Redundancy analysis further identified anthropogenically influenced inorganic nitrogen, together with water temperature, transparency, and salinity, as key environmental drivers shaping community structure. βNTI analysis indicated that community assembly was governed by the combined effects of deterministic and stochastic processes. Overall, this study highlights how environmental gradients and human pressures jointly regulate metazoan dynamics, providing insights for biodiversity conservation in human-impacted coastal seas. Full article

Minimal access cardiac surgery (MACS) can mitigate the increasing risk profile of cardiac surgery patients and is associated with improved postoperative outcomes. One of the ways to manage the steep learning curve of MACS is the use of surgical simulation training. We conducted a narrative review to identify the relevant literature discussing MACS simulation training. We identified 20 studies using our search strategy. Various platforms were represented: high-fidelity (n = 8), low-fidelity (n = 6), and animal studies (n = 6). Virtual reality (VR) appeared in two wet-lab studies as an adjunct. The surgical approach was video-assisted thoracoscopic surgery (VATS) in 11 and robotic-assisted thoracoscopic surgery (RATS) in nine. The most simulated procedure was minimal access mitral valve (MV) repair (n = 16). Most studies (n = 16) evaluated the impact of simulation training on the surgical skill of participants with varying baseline MACS experience. A small proportion of included studies (n = 4) carried out only fidelity testing. While some standardised assessment tools were used, there was considerable variation in how surgical skill and fidelity were assessed. There are an increasing number of publications on MACS simulation training, with equal focus on bench and animal models. MV procedures were the most simulated, suggesting a drive towards increasing the scope of minimal access MV training. Full article

Background and Objectives: Age-related macular degeneration (AMD) is a multifactorial retinal disease in which inflammation and blood-retinal barrier dysfunction may contribute to disease pathogenesis. Claudin-5 is a key tight-junction protein involved in endothelial barrier integrity. Hemogram-derived indices such as the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), and pan-immune-inflammation value (PIV) reflect systemic inflammatory status. This study aimed to evaluate circulating claudin-5 levels and systemic inflammatory indices in patients with wet and dry AMD and to investigate their associations with visual function. Materials and Methods: This prospective case–control study included 90 participants: 30 patients with wet AMD, 30 patients with dry AMD, and 30 healthy controls. All participants underwent detailed ophthalmologic examination, including best-corrected visual acuity (BCVA) assessment and optical coherence tomography. Serum claudin-5 levels were analyzed by enzyme-linked immunosorbent assay, and NLR, PLR, MLR, and PIV were calculated from complete blood count parameters. Group comparisons, correlation analyses, and age-adjusted analyses were performed using appropriate statistical methods. Results: Age differed significantly among the groups (p = 0.032), with the highest median age in the dry AMD group. BCVA (logMAR) also differed significantly (p < 0.001), and both AMD groups had worse visual acuity than controls. Median serum claudin-5 levels were 2.42 in controls, 3.28 in the wet AMD group, and 3.10 in the dry AMD group, with no significant between-group difference (p = 0.280). NLR, MLR, and PIV were also comparable among the groups (p = 0.310, p = 0.410, and p = 0.752, respectively). PLR differed among the groups (p = 0.019), and post hoc analysis showed higher PLR values in the dry AMD group than in the wet AMD group (p = 0.013). However, this difference was no longer statistically significant after adjustment for age (adjusted p = 0.098). Serum claudin-5 was not significantly correlated with age, BCVA, NLR, PLR, MLR, or PIV. Conclusions: Circulating claudin-5 did not differ significantly across AMD phenotypes and was not associated with age, visual function, or systemic inflammatory indices. Although PLR differed between wet and dry AMD before adjustment for age, the overall findings suggest that single-point peripheral serum measurements of claudin-5 may have limited utility in reflecting local retinal barrier-related changes in AMD. Larger longitudinal studies are needed to clarify its potential biomarker role. Full article

Tunnels excavated in non-coal oil- and gas-bearing strata may experience the seepage and intermittent ingress of an oil–gas–water mixture during construction, creating aggressive corrosive conditions that can compromise the integrity of primary support and the safety margin of the final lining. However, the coupled degradation mechanism of primary support and its cascading effect on lining safety under such conditions remain poorly understood. Based on the Huaying Mountain Tunnel project, this study investigates the corrosion-driven damage evolution of primary support and its implications for the structural safety of the secondary lining under wet–dry cycling exposure. Accelerated wet–dry cycling tests were performed on concrete specimens using an on-site crude-oil–formation-water mixture collected during tunnelling, with exposure levels ranging from 0 to 120 cycles. Laboratory observations were then combined with inverse identification of degradation-dependent material parameters to establish a corrosion-informed mechanical description, which was implemented in numerical simulations for structural response assessment. Results show a staged evolution of mechanical properties, with an initial increase followed by progressive deterioration. After 120 cycles, compressive strength, tensile strength, and elastic modulus decreased by approximately 18.9%, 23.1%, and 17.4%, respectively. Degradation is more pronounced in the corroded zone, with tensile capacity and stiffness deteriorating earlier than compressive resistance. Numerical results indicate that corrosion leads to significant stress redistribution and damage development. The sidewall tensile stress reaches 2.80 MPa after 120 cycles, exceeding the post-corrosion capacity, while the safety factor drops below the code threshold at 90 cycles. The overall safety probability decreases from 1.0 to 0.4, accompanied by a degradation in safety grade from Level I to Level IV. These findings provide a quantitative basis for deterioration assessment, safety verification, and maintenance planning for tunnels subjected to oil–gas corrosive environments. Full article

Tidal flats are ecologically important coastal ecosystems with significant carbon stocks; however, although taxon-specific carbon assessments have been conducted in other coastal systems, such data remain scarce for Korean tidal flats, where bivalve aquaculture is actively practiced. This study examined the macrobenthic community structure and carbon stock contributions in two tidal flats on the west coast of South Korea (Seosan and Seocheon) through field surveys conducted in May and August 2023. A total of 110 invertebrate species from five phyla were identified. Annelida showed the highest species richness at both sites (47.4–62.3% of total species), whereas Mollusca dominated biomass and carbon stocks. Two-way PERMANOVA confirmed significant differences in community structure between sites (Pseudo-F = 15.376, p < 0.001) and months (Pseudo-F = 9.489, p = 0.001), and a significant site × month interaction (Pseudo-F = 4.800, p = 0.028). Nonparametric ANCOVA revealed that Mollusca exhibited a significantly higher carbon mass conversion rate relative to wet weight than all the other taxa (p < 0.001). Rank abundance curves and principal coordinate analyses indicated that Ruditapes philippinarum accounted for 86.9% of total carbon mass in Seosan, whereas R. philippinarum and Mactra veneriformis together accounted for 73.5% in Seocheon, despite Annelida comprising the majority of species richness. These results indicate that the macrobenthic carbon stocks of Korean tidal flats are disproportionately concentrated in a few dominant calcifying Bivalvia species rather than across the overall community diversity, with implications for coastal ecosystem management. Full article