Search Results (7,031)

Selective depression of serpentine remains a major challenge in the flotation of low-grade nickel sulphide ores because serpentine slimes impair concentrate grade and recovery. In this study, four structurally related micromolecular depressants bearing amino and phosphonic functionalities were designed, synthesized and systematically evaluated. Micro-flotation screening (depressant range: 0–20 mg·L⁻¹) and bench-scale tests identified an operational optimum near pH 9 and a reagent dosage of ≈18 mg·L⁻¹; potassium butyl xanthate (PBX) was used as a collector and methyl isobutyl carbinol (MIBC) as a frother. Phosphonate-containing molecules (PMIDA and GLY) delivered the largest gains in pentlandite recovery and concentrate selectivity compared with carboxylate analogues and a benchmark depressant. Mechanistic studies (zeta potential, adsorption isotherms, FT-IR, and XPS) indicated that selective adsorption of amino and phosphonate groups on serpentine occurs via coordination with surface Mg sites and by altering the electrical double layer. The DLVO modelling showed that these reagents generate an increased repulsive barrier, mitigating slime coating and entrainment. Contact-angle measurements confirmed selective hydrophilization of serpentine while pentlandite remained hydrophobic. These findings demonstrate that incorporating targeted phosphonate chelation into small-molecule depressants is an effective strategy to control serpentine interference and to enhance flotation performance. Full article

Glaucoma is a major ocular neurodegenerative disease and a leading cause of irreversible blindness worldwide, with prevalence projected to exceed 110 million by 2040. Although lowering intraocular pressure (IOP) remains the only proven treatment, glaucoma arises from a complex interplay of genetic, local, and systemic factors—including oxidative stress, vascular dysregulation, mitochondrial dysfunction, and neuroinflammation. Emerging evidence suggests that modifiable lifestyle factors may influence these pathogenic pathways. In this review, higher dietary nitrate from leafy greens is consistently associated with lower primary open-angle glaucoma risk, aligning with nitric-oxide-mediated endothelial support and more stable ocular perfusion pressure. Flavonoids (anthocyanins and flavanols), carotenoids (lutein/zeaxanthin), and B vitamins have strong biological rationale for glaucoma prevention but have limited support from long-term, large population-based studies. The effect of polyunsaturated fats on glaucoma remains inconsistent and warrants source-(plant vs. animal) and substitution-based analyses. Consistent protective effects of aerobic exercise and high-quality sleep may be associated with favorable metabolic profiles and ocular perfusion, potentially mitigating retinal ganglion cell loss. Conversely, smoking and alcohol use are frequently coupled with poorer diet quality (e.g., lower vegetable intake) and heightened oxidative stress, which may exacerbate glaucomatous neurodegeneration. However, much of the current literature is constrained by cross-sectional designs, reliance on self-reported food frequency questionnaires, and insufficient use of structural endpoints such as retinal nerve fiber layer imaging. This review focuses on the potential of lifestyle modification and future directions in prevention and treatment strategies for glaucoma, highlighting the need for large-scale, multi-ethnic, genotype-stratified longitudinal studies and randomized controlled trials to establish causality and define optimal intervention strategies. Full article

The increasing penetration of renewable energy, such as photovoltaic generation, makes it essential to enhance power system dynamic performance through improved grid-forming control strategies. In the grid-forming control system, the virtual synchronous generator control (VSG) is currently widely used. However, the inertia (J) and damping (D) in the traditional VSG are fixed values, which can result in large overshoots and long adjustment times when dealing with disturbances such as load switching. To address these issues, this paper proposes an adaptive virtual synchronous generator (VSG) control strategy for grid-side inverters, which is accomplished by adaptively adjusting the VSG’s inertia and damping. Firstly, we established a photovoltaic-storage VSG grid-forming system; here, the photovoltaic power is boosted through a DC-DC converter, and the energy storage is connected to the common DC bus through a bidirectional DC-DC converter. We analyzed how J and D shape the system’s output characteristics. Based on the power-angle characteristic curve, the tanh function was introduced to design the control function, and a JD collaborative adaptive control (ACL) strategy was proposed. Finally, simulation experiments were conducted under common working conditions, such as load switching and grid-side voltage disturbance, to verify the results. From the results shown, the proposed strategy can effectively improve the response speed of the system, suppress system overshoot and oscillation, and, to a certain extent, improve the dynamic performance of the system. Full article

Background/Objectives: To determine the clinical features of different types of intermittent exotropia according to the distance and near angles of exodeviation. Methods: This study included 5331 patients with intermittent exotropia. The patients were divided into three groups according to the near-distance differences in their exodeviations: (1) Basic-type: difference between distant and near angles of the exodeviation < 10 prism diopters (PD); (2) Convergence insufficiency (CI)-type: near-distance angle ≥ 10 PD; (3) Divergence excess (DE)-type: distance-near angle ≥ 10 PD. The main outcome measures were demographics, clinical characteristics of exotropia, subjective symptoms, medical history, and family history. Results: Overall, 4599 (86.2%) patients had basic-type exotropia, 500 (9.4%) had CI-type, and 232 (4.4%) had DE-type exotropia. Older age and greater magnitude of myopia were associated with CI-type exotropia. A-pattern exotropia, superior oblique (SO) overaction, good fusional control, good stereoacuity, and diplopia were most common in CI-type exotropia. SO underaction and photophobia were most frequently observed in DE-type exotropia compared to the other types. Conclusions: The clinical characteristics varied among the different types of intermittent exotropia. CI-type exotropia was most frequently associated with older age and greater myopia. DE-type exotropia was associated with frequent photophobia. Full article

A numerical method to estimate the plasma characteristics with the variation in control parameters is suggested with an artificial intelligence model using limited finite datasets. A transformer-based regression method was applied to estimate the spatial profiles of plasma characteristics in a DC magnetron sputtering system from limited data obtained by a two-dimensional particle-in-cell simulation under varying pressure. Based on the obtained simulation data, an artificial intelligence method successfully predicts the energy and angular distribution of ions incident on the target. This approach enables the quantitative estimation of the impact of various system parameter changes on plasma characteristics using only a limited number of simulation results. It is beneficial for practical applications, such as process optimization, because the ion energy and angle distributions can be estimated very fast without simulating all the cases. Full article

The study investigates the impact of motions of floating offshore wind turbine platforms on wake evolution and overall wind farm performance, employing large-eddy simulation (LES) and dynamic wake modeling method. First, the differences between wakes of floating and bottom-fixed wind turbines under forced motion are examined. Subsequently, a systematic comparative analysis is performed for four representative floating platform configurations—Spar, Semi-submersible, Tension-Leg Platform (TLP), and Monopile (Mnpl)—to assess wake dynamics and downstream turbine responses within tandem-arranged arrays. Results indicate that platform pitch motion, by inducing periodic variations in the rotor’s relative inflow angle, significantly enhances wake unsteadiness, accelerates kinetic energy recovery, and promotes vortex breakdown. Tandem-arrange turbines simulations further reveal that platform-dependent motion characteristics substantially influence wake center displacement, velocity deficit, downstream turbine thrust, and overall power fluctuations at the wind farm scale. Among the examined configurations, the Spar platform exhibits the most pronounced wake disturbance and the largest downstream load and power oscillations, with rotor torque and thrust increasing by 10.2% and 10.6%, respectively, compared to other designs. This study elucidates the coupled mechanisms among 6-DOFs (Six Degrees Of Freedom) motions, wake evolution, and power performance, providing critical insights for optimizing floating wind farm platform design and developing advanced cooperative control strategies. Full article

Edible coatings are widely used to modulate oil uptake and moisture in fried foods. In this study, we evaluated a microfluid-assisted flow-blurring spray against conventional application by dipping/spraying, focusing on the coating efficiency and preliminary implications for sustainable process. This study combines benchtop experiments with a near-nozzle numerical analysis where the gas–liquid interface and primary breakup are modeled using the Volume of Fluid (VOF) approach implemented in OpenFOAM, configured for a flow-blurring geometry to generate whey protein isolate (WPI) coatings. Viscosity, density, solid content, and contact angle were validated experimentally and used in the simulation setup. An image-based droplet pipeline quantified spray characteristics, yielding a volumetric median diameter D₅₀ = 83.69 µm and confirming process uniformity. Contact angles showed marked substrate dependence: hydrophilic surfaces, 68°–85°; hydrophobic surfaces, 95°–110°. For turkey sausages, sessile-drop contact angles were not determinable (N.D.) due to wicking/roughness; wettability was therefore assessed on smooth surrogates and via performance metrics. Fit-for-purpose simulation procedures are outlined. Microfluidic application (WPI-McF) lowered oil uptake versus uncoated controls. Together, robust modeling, targeted image analytics, and high-precision microfluidics enable rational tuning of coating microstructure and barrier performance, offering a scalable pathway to reduce lipid content and enhance fried food quality. Full article

Model-based maximum torque per ampere (MTPA) control methods of interior permanent magnet synchronous motors (IPMSM) often suffer from poor robustness. To address this issue, a new MTPA control method based on current angle searching with sliding-mode extremum seeking is proposed. Based on Lyapunov’s criterion, the stability of the proposed MTPA method is proven. By analyzing the formation and switching process of a sliding-mode surface, the convergence speed and control accuracy of the proposed MTPA are derived. Compared with the conventional MTPA method, based on the sinusoidal excitation extremum search algorithm, the proposed method does not require either a sinusoidal excitation signal or high-pass and low-pass filters. The effectiveness of the proposed method is verified by experiment. Full article

Patients on hemodialysis (HD) often experience changes in body composition due to metabolic disorders. Phase angle (PhA) is a marker of tissue integrity and may reflect overall functional condition. This study evaluated body composition and its relationship with PhA in 53 HD patients (27 women, 26 men) over 40 years old, compared with 106 age- and sex-matched healthy controls. Body composition was assessed using bioelectrical impedance analysis (BIA), measuring skeletal muscle mass (SMM), fat tissue, total bone mass (BM), and PhA. HD patients had significantly lower fat mass and PhA than controls (p < 0.001). The prevalence of low SMM and BM was higher in patients, though not statistically significant. Sex differences were generally not significant, except for a higher prevalence of low BM in female controls (p < 0.001). After adjusting for age and sex, PhA was positively associated with SMM% (p = 0.021) and BM (p = 0.035) in HD patients only. These results indicate that PhA–body composition relationships differ between HD patients and healthy individuals, highlighting PhA as a potential marker of body composition disturbances in HD. Full article

The southwestern region of China is highly susceptible to landslides due to steep terrain, fractured geology, and intense rainfall. This study focuses on the Xiluodu Reservoir area in Yunnan Province and applies Geographic Information System (GIS) techniques together with ten key spatial factors—such as slope, lithology, elevation, and distance to rivers—to perform a quantitative landslide risk assessment. In addition to the individual Certainty Factor (CF) and Logistic Regression (LR) models, we developed an integrated CF–LR coupled model to overcome their respective limitations: the CF model’s sensitivity to specific factor attributes but neglect of factor interactions, and the LR model’s robust weight estimation but weak representation of attribute heterogeneity. By combining these strengths, the CF–LR model achieved superior predictive performance (AUC = 0.804), successfully capturing 92.5% of historical landslide events within moderate-to-high risk zones. The results show that lithology, slope angle, and proximity to rivers and roads are dominant controls on susceptibility, with landslides concentrated on soft rock slopes of 30–40° and within 600–900 m of rivers. Compared with previous coupled approaches in similar mountainous reservoir settings, our CF–LR model provides a more balanced and interpretable framework, enhancing both classification accuracy and practical applicability. These findings demonstrate that GIS-based CF–LR integration is a novel and reliable tool for landslide susceptibility mapping, offering important technical support for disaster prevention and risk management in large reservoir regions. Full article

Background/Objectives: The purpose of the study is to determine and compare the accuracy and efficiency of two dynamic navigation systems (DNS)—Navident (ClaroNav, Canada) and X-Guide (Nobel Biocare, Switzerland)—vs. a free-hand (FH) approach in performing endodontic microsurgery (EMS) on human cadavers. Methods: a total of 119 roots of six cadavers were randomly divided into three groups (Navident/X-Guide/FH). The cadavers’ jaws were scanned pre-operatively with computed tomography. The DICOM data were uploaded and digitally managed with software interfaces for registration, calibration, and virtual planning of EMS. Osteotomy was performed under DNS control and using a dental operating microscope (FH control group). Post-operative scans were taken with same settings as preoperative. Accuracy was then determined by comparing pre- and post-scans of coronal and apical linear, angular deviation, angle, length, and depth of apical resection. Efficiency was determined by measuring the procedural time of osteotomy, apicectomy, retro-cavity preparation, the volume of substance, and cortical bone loss, as well as iatrogenic complications. Outcomes were also evaluated in relation to different operators’ skill levels. Descriptive statistics and inferential analyses were conducted using R software (4.2.1). Results: DNS demonstrated better efficiency in osteotomy and apicectomy, second only to FH in substance and cortical bone loss. Both DNS approaches had similar accuracy. Experts were faster and more accurate than non-experts in FH, apart from resection angle, length and depth, and retro-cavity preparation time, for which comparison was not statistically significant. The Navident and X-guide groups had similar trends in increasing efficiency and accuracy of EMS. All complications in the FH group were performed by non-experts. The X-guide group demonstrated fewer complications than the Navident group. Conclusions: Both DNS appear beneficial for EMS in terms of accuracy and efficacy in comparison with FH, also demonstrating the decreasing gap of skill expertise between experts and novice operators. Through convenient use X-guide diminishes the level of iatrogenic complications compared to Navident. Full article

The purpose of this study was to characterize the inter-segmental coordination of hip, knee, and ankle movement of the kicking leg during instep kicking for experienced athletes and novices, using vector coding as a non-linear technique. Motion capture and electromyographic data were collected for 14 soccer-majored college students and 32 novices performing the instep kicking task. The percentage of time spent on the coordination patterns, defined based on hip–knee and knee–ankle coupling angles, was calculated and compared. The agonist–antagonist activity ratio was calculated and compared. The time percentages of the knee–ankle shank dominance of the experienced athletes during the whole kicking movement were significantly greater than those of the novices (p < 0.050). Athletes achieving greater maximum ball speed had more knee flexion dominant coordination patterns in the back swing and leg-cocking, and knee extension dominant coordination patterns in the leg acceleration phase. The lower activity ratio of the tibialis anterior and gastrocnemius muscles contributed significantly to increasing kicking accuracy. These results underscore the value of vector coding in identifying key inter-segmental coordination features and directly support targeted soccer kick training. The dynamic stability exercises involving knee flexion and extension to optimize power transfer for speed, as well as activation and relaxation control exercises of the lower leg muscles to improve the kicking accuracy, may be effective ways to enhance instep kicking motor control ability and performance for soccer athletes. Full article

Tight gas reservoirs are characterized by low porosity, low permeability, and strong heterogeneity. CO₂ flooding, as an important approach for enhancing gas recovery while achieving carbon sequestration, is often restricted by gas channeling. Based on the sandstone reservoir parameters of the Shihezi Formation in the Ordos Basin, a two-dimensional fracture–matrix coupled numerical model was developed to systematically investigate the effects of fracture number, fracture inclination, fracture width, injection pressure, and permeability contrast on gas breakthrough time and sweep efficiency. A second-order regression model was further established using response surface methodology (RSM). The results show that a moderate fracture density can extend breakthrough time and improve sweep efficiency, while permeability contrast is the fundamental factor controlling gas channeling risk. When the contrast increases from 0.7 to 9.9, the breakthrough efficiency decreases from 88.5% to 68.9%. The response surface analysis reveals significant nonlinear interactions, including the coupled effects of fracture number with fracture width, injection pressure, and inclination angle. Under the optimized conditions, the breakthrough time can be extended to 46,984 h, with a corresponding sweep efficiency of 87.7%. These findings provide a quantitative evaluation method and engineering optimization guidance for controlling CO₂ channeling in tight gas reservoirs. Full article

To investigate characteristic stress and energy evolution law of carbonaceous shale under dry–wet cycles and fissure angle, several samples with prefabricated fissure angles were prepared and subjected to the coupled influence of dry–wet cycles and loading. The results show that the closure stress, initiation stress, damage stress, and peak stress gradually increase with the increase in confining pressure, effectively suppressing the initiation and propagation of the crack. At the same time, the total energy, elastic energy, and dissipated energy at the crack characteristic stress are enhanced by a linear function relationship, significantly improving the bearing capacity and energy storage capacity of carbonaceous shale. The dry–wet cycle is regarded as the driving force of damage, reducing the crack characteristic stress and the total energy, elastic energy, and dissipated energy of crack characteristic stress. This results in a weakened capacity of the rock samples to store elastic strain energy, ultimately contributing to the damage degradation of carbonaceous shale. The anisotropic damage of rock is controlled by fissure angle. The crack characteristic stress and the total energy, elastic energy, and dissipated energy of crack characteristic stress with a 45° fissure angle is the smallest. Finally, the energy storage level at the damage stress (Kcd) can be used as an early warning indicator for rock failure. Full article

Mixed structures with lightweight steel added stories are particularly vulnerable to damage and failure at the joints during seismic events. To evaluate the secondary seismic behavior of the joints in lightweight steel added stories after seismic damage repair, a low-cycle load test was conducted in this study. Following the initial damage, carbon fiber-reinforced polymer (CFRP) was applied for reinforcement, along with epoxy resin for the repair of concrete cracks. The experimental analysis focused on the structural deformation, failure characteristics, and energy dissipation capacity in both the original and repaired joint states. On the basis of the experimental findings, finite element analysis was carried out to examine the influence of varying CFRP layer configurations on the seismic performance of the repaired joints. The results revealed a significant change in the damage pattern of the repaired specimen, shifting from secondary surface damage to significant concrete deterioration localized at the bottom of the column. The failure mechanism was characterized by the CFRP-induced tensile forces acting on the concrete at the column base, following considerable deformation at the beam’s end. When compared to the original joint, the repaired joints exhibited markedly improved performance, with a 33% increase in horizontal ultimate strength and an 85% increase in energy dissipation capacity at failure. Additionally, the rotation angle between the beams and columns was effectively controlled. Joints repaired with two layers of CFRP demonstrated superior performance in contrast to those with a single layer. However, once the repaired joints met the required strength, further increasing the number of CFRP layers had a minimal influence on the mechanical properties of the joints. The proposed CFRP-based seismic retrofit method, which accounts for the strength degradation of concrete in damaged joints due to earthquake-induced damage, has proven to be both feasible and straightforward, offering an easily implementable solution to improve the seismic behavior of structures. Full article