Search Results (791)

This review highlights the growing relevance of ion-exchange nanofibrous membranes (IEX-NFMs) in membrane chromatography (MC) for protein purification, emphasising their structural advantages such as high porosity, tunable surface functionality, and low-pressure drops. While the adsorption of IEX-NFMs in MC is expanding due to their potential for high throughput and rapid mass transfer, a critical limitation remains: the precise binding capacity of these membranes is not well understood. Traditional experimental methods to evaluate protein–membrane interactions and optimise binding capacities are labour-intensive, time-consuming, and costly. Therefore, this review underscores the importance of computational modelling as a viable predictive approach to guide membrane design and performance prediction. Yet major obstacles persist, including the challenge of accurate representation of the complex and often irregular pore structures, as well as limited and/or oversimplified adsorption models. Along with molecular-scale simulations such as molecular dynamics (MD) simulations and quantum simulations, meso-scale simulations can provide insight into protein–fibre and protein–protein interactions under varying physicochemical conditions for larger time scales and lower computational burden. These tools can help identify key parameters such as binding accessibility, ionic strength effects, and surface charge density, which are essential for the rational design and performance prediction of IEX-NFMs. Moreover, integrating simulations with experimental validation can accelerate optimisation process while reducing cost. This technical review sets the foundation for a computationally driven design framework for multifunctional IEX-NFMs, supporting their use in next-generation chromatographic separations and broadening their applications in bioprocessing and analytical biotechnology. Full article

Background: Postoperative abdominal adhesions are a common and serious complication following abdominal surgery, often leading to chronic pain, bowel obstruction, or infertility. This study aimed to evaluate the efficacy of the new starch-based absorbable hemostatic agent and dressing, BioSight, in comparison with a predicate device (4DryField^® PH) for the prevention of abdominal adhesions in a rat model. Methods: A total of 90 Sprague–Dawley rats were used to establish an intra-abdominal adhesion model and assigned to the BioSight, 4DryField^® PH, or control group. Standardized injuries were created on the cecum and parietal peritoneum, followed by application of the designated materials. Animals were sacrificed at 2, 4, and 12 weeks for macroscopic adhesion scoring and histopathological evaluation. Adhesion area, adhesion strength, and tissue thickness were assessed using established scoring systems, and local healing was examined by H&E staining. All quantitative data were analyzed using one-way ANOVA. Conclusions: In a rat peritoneal adhesion model, BioSight exhibited pronounced anti-adhesion efficacy comparable to 4DryField^® PH. Macroscopic evaluation showed consistently low adhesion scores (≤0.4) across all time points up to 12 weeks, while histological analysis confirmed reduced adhesion thickness, with BioSight displaying numerically lower values, particularly at early stages (251.3 ± 137.4 µm vs. 323.2 ± 174.6 µm at Week 2). This performance is attributed to rapid in situ hydrogel formation that provides effective temporary tissue separation, limits early fibrin deposition and inflammatory cell infiltration, and supports hemostasis. Importantly, the starch-based hydrogel exhibits a balanced biodegradation profile—persisting long enough to protect injured tissues during the critical inflammatory and fibroproliferative phases, yet undergoing complete enzymatic resorption thereafter without adverse tissue reactions. Collectively, these results highlight the anti-adhesion functionality of BioSight and support the clinical potential of plant-derived starch-based bioresorbable surgical adjuncts. Full article

River-training structures such as spur dikes are frequently used in the field of river engineering, which play a critical role in flow regulation and stabilization of the riverbank. However, previous studies lack a precise prediction of factors inducing scour and turbulence phenomena, such as tip velocity, for optimal design of the spur dikes. This study addresses a key gap in previous research by predicting tip velocity around spur dikes using advanced and interpretable machine learning models while simultaneously evaluating the influence of key geometric and hydraulic parameters. For this purpose, the current study utilized advanced artificial intelligence (AI) techniques like Gaussian Process Regression (GPR), Categorical Boosting (CatBoost), Random Forest (RF), and Extreme Gradient Boosting (XGBoost), optimized with Particle Swarm Optimization (PSO), to predict tip velocity in the vicinity of the spur dike. In this paper, a small dataset of 69 laboratory-scale experimental trials was collected; therefore, the chosen AI models were selected for their ability to handle such limited data points. In this study, the input parameters included Froude number (Fr), separation length to spur dike length ratio (L/l), and incidence angle (β), while the output parameter was tip velocity. The selected four AI models were trained on 70%, 15%, and 15% of the data for the training, testing, and validation phases, respectively. SHapley Additive exPlanations (SHAP) analysis was used to observe the influence of the critical parameters on the tip velocity. The results demonstrated the superior performance of GPR, followed by the CatBoost model, compared to other models. GPR and CatBoost show greater values of coefficient of determination (R²) (GPR R² = 0.972 and CatBoost R² = 0.970) and lower values of root mean square error (RMSE) (GPR RMSE = 0.0107 and CatBoost RMSE = 0.0236). The result of the heatmap and SHAP analysis indicated a greater influence of Fr and L/l and a lower impact of β on the tip velocity. The results of this study recommend the utilization of GPR and CatBoost for precise and robust performance of the hydrodynamic phenomenon around the spur dikes, supporting scour mitigation strategies in river engineering. Full article

Background/Objectives: Oropharyngeal squamous cell carcinoma (OPSCC) management has shifted following recognition of HPV-driven disease. Neoadjuvant chemotherapy (NAC) has historically failed to improve overall survival (OS) in mixed head and neck cohorts, although contemporary HPV-stratified series suggest NAC may enable treatment de-escalation. We aimed to narratively synthesize OPSCC-specific evidence on NAC focusing on primary and nodal response, pathologic complete response (pCR), survival, and functional outcomes. Methods: We conducted a narrative review of PubMed, selecting primary studies in which OPSCC outcomes were reported separately (surgery- or chemoradiotherapy [CRT]-based strategies; HPV status when available). We extracted study design, treatment regimens, response outcomes, survival, and toxicity data. Results: Pre-HPV studies showed variable responses and no consistent OS advantage over locoregional therapy. In the HPV era, non-comparative cohorts of NAC followed by transoral surgery reported substantial downstaging and high pCR rates at both the primary site and regional nodes, with 3–5-year OS frequently ≥80%. NAC+CRT paradigms demonstrated high clinical CR rates and OS exceeding 80–90%, and lower feeding-tube dependence and reduced swallowing morbidity in de-escalated regimens. Comparative retrospective series suggest NAC + surgery may be associated with lower rates of distant metastases and feeding-tube use compared with CRT or upfront surgery, although interpretation is limited by selection bias, regimen heterogeneity, and small sample sizes. Conclusions: While randomized trials have not established an OS advantage for NAC over standard CRT in head and neck cancer overall, HPV-positive OPSCC shows emerging evidence that systemic intensification with NAC may enable surgical and/or radiation de-escalation with promising oncologic and functional outcomes. Full article

End-of-life wind turbine blade accumulation is a growing global materials management problem and current industrial recycling routes for glass fiber-reinforced polymer composites remain limited in material recovery value. There is limited understanding on how to recover clean glass fibers while keeping thermal exposure and energy input low, and existing studies have not quantified whether very short isothermal thermal residence can still result in complete matrix removal. The hypothesis of this study is that a mild two-step thermochemical sequence can recover clean glass fibers at lower temperature and near zero isothermal dwell if pyrolysis and oxidation are separated. We used wind-blade epoxy-based GFRP in a step-batch reactor and combined TGA-based thermodynamic mapping, short pyrolysis at 425 °C, and mild oxidation at 475 °C with controlled dwell from zero to thirty minutes. We applied model-free kinetics and machine learning methods to quantify activation energy trends as a function of conversion. The thermal treatment of 425 °C for zero minutes in nitrogen, followed by 475 °C for fifteen minutes in air, resulted in mechanically sound, visually clean white fibers. These fibers retained 76% of the original tensile strength and 88% of the Young’s modulus, which indicates the potential for energy-efficient GFRP recycling. The activation energy was found to be approximately 120 to 180 kJ mol⁻¹. These findings demonstrate energy lean recycling potential for GFRP and can inform future industrial scale thermochemical designs. Full article

Microalgae have been characterized as an effective raw material for obtaining bioproducts from a biorefinery approach. However, production costs limit the large-scale production of microalgae, which makes these processes uncompetitive in the market. Therefore, in the present work, different agricultural fertilizers were evaluated as low-cost culture media for microalgae growth and the use of the biomass for biocrude production. The tests were carried out in three phases: phase I, Laboratory scale 1 L Erlenmeyer (Boeco, Hamburg, Germany) and phase II–III Pilot scale with cylindrical photobioreactors (PBRs) (Atb services S.A.S, Medellin, Colombia) with a capacity of 20 L. In phase I, four commercial fertilizers Crecilizer^® (C), Florilizer^® (F) (Fertilizer, Bogota, Colombia), AcuaLeaf Macros^® (Ma), and AcuaLeaf Micros^® (Mi) (Deacua, Medellin, Colombia) were tested separately and in combination (C + Ma, F + M, and Ma + Mi). The most effective treatments (C and F) in phase I were chosen for scale-up during phase II. In phase III, the concentration of the best treatment from phase II was increased. The biomass obtained from the best phase III treatment showed a cultivation medium cost 50% lower than the biomass obtained using Bold’s Basal Medium (BBM). Following each treatment, the harvested biomass was processed via hydrothermal liquefaction (HTL) to yield biocrude. The reduction in culture medium cost contributed to an estimated 40% decrease in the relative biocrude yield cost. Full article

Biogas upgrading and bottling represent essential processes in transforming raw biogas produced via the anaerobic digestion of organic waste into high-purity biomethane (≥95% CH₄), a renewable energy source suitable for applications in cooking, transportation, and electricity generation. Upgrading technologies, such as membrane separation, pressure swing adsorption (PSA), water and chemical scrubbing, and emerging methods, like cryogenic distillation and supersonic separation, play a pivotal role in removing impurities like CO₂, H₂S, and moisture. Membrane and hybrid systems demonstrate high methane recovery (>99.5%) with low energy consumption, whereas chemical scrubbing offers superior gas purity but is limited by high operational complexity and cost. Challenges persist around material selection, safety standards, infrastructure limitations, and environmental impacts, particularly in rural and off-grid contexts. Bottled biogas, also known as bio-compressed natural gas (CNG), presents a clean, portable alternative to fossil fuels, contributing to energy equity, greenhouse gases (GHG) reduction, and rural development. The primary aim of this research is to critically analyze and review the current state of biogas upgrading and bottling systems, assess their technological maturity, identify performance optimization challenges, and evaluate their economic and environmental viability. The research gap identified in this study demonstrates that there is no comprehensive comparison of biogas upgrading technologies in terms of energy efficiency, price, scalability, and environmental impact. Few studies directly compare these technologies across various operational contexts (e.g., rural vs. urban, small vs. large scale). Additionally, the review outlines insights into how biogas can replace fossil fuels in transport, cooking, and electricity generation, contributing to decarbonization goals. Solutions should be promoted that reduce methane emissions, lower operational costs, and optimize resource use, aligning with climate targets. This synthesis highlights the technological diversity, critical barriers to scalability, and the need for robust policy mechanisms to accelerate the deployment of biogas upgrading solutions as a central component of a low-carbon, decentralized energy future. Full article

Background/Objectives: Cranioplasty (CP) is associated with high complication rates (20–50%), and the optimal choice between patient-specific implants (PSIs) and hand-molded (HM) alternatives remains debated. This systematic review and meta-analysis aims to compare surgical and postoperative outcomes between PSIs and HM implants. Methods: A systematic search was performed in three databases to identify studies reporting surgical site infection (SSI), implant removal, reoperation, operative time or cosmetic outcome for PSIs and/or HM implants. Two-arm studies of the same material were analyzed separately from pooled single- and two-arm studies. Results: 125 observational studies involving 10,034 patients were included. In two-arm comparisons, PSIs reduced implant removal for titanium (OR 0.34, p = 0.053) and PMMA (OR 0.56, p = 0.188), while SSI rates showed no meaningful difference between groups. In one-arm analyses, PSIs demonstrated lower explantation probabilities (titanium 6.1%, PMMA 7.9%) compared with HM alternatives (titanium 9.9%, PMMA 14.2%), alongside shorter operation times and fewer reoperations. Cosmetic outcomes consistently favored PSIs. Conclusions: PSIs demonstrate advantages in efficiency, durability, and esthetics compared with HM implants, supporting their preferential use where resources allow. HM implants remain a cost-effective option in resource-limited settings. Due to the observational nature of the included studies and differences in study populations across arms, the findings should be interpreted with caution. Full article

In this paper, the conceptual hydrogeological circulation model of natural mineral waters from Ribeirinho and Fazenda do Arco hydromineral concession (Castelo de Vide) is updated. These waters are exploited by the Super Bock Group, as bottled waters, and are commercially labeled as Água Vitalis. The physico-chemical data (2004–2024) of these waters were processed regarding their joint interpretation with recent isotopic (δ²H and δ¹⁸O) data. The study region is dominated by the Castelo de Vide syncline, which develops along the southern limit of the Central Iberian Zone. These natural mineral waters have low electrical conductivity (EC) mean values (42.80 < EC_mean < 54.45 μS/cm) and a slightly acidic pH (5.14 < pH_mean < 5.46), making them hyposaline waters. The recharge area of this aquifer system coincides fundamentally with the outcrops of Lower Ordovician quartzites. The updated conceptual circulation model presented in this work is essentially developed on the basis of the chloride–sodium signatures of these waters, explained by the preferential recharge of meteoric waters (δ²H and δ¹⁸O) and low water–rock interaction temperature. Such isotopic results seem to indicate the non-existence of a flow continuity between the two blocks (NW and SE) of the quartzite ridges, separated by a fault with a local orientation approximately N-S, as indicated by the most enriched isotopic values of the waters from borehole AC22 (δ¹⁸O = −5.90‰ vs. V-SMOW) located in the SE block, compared to the average isotopic value of the waters from the other boreholes (Vitalis I, II, III, IV, V and VI) located in the NW block (δ¹⁸O_mean = −6.30‰ vs. V-SMOW). This study enhances the understanding of the hydrogeological and geochemical processes controlling low-mineralized (hyposaline) natural mineral waters, widely used for therapeutic and commercial purposes. Despite their global importance, detailed hydrogeological and isotopic studies of such systems are still scarce, making this conceptual model a valuable reference for their sustainable management. Full article

Background: Screw loosening is considered a leading mechanical complication in implant-supported restorations. Hybrid abutments, combining a titanium base with a ceramic mesostructured, were proposed to enhance stability and esthetics. Objective: We aimed to evaluate screw-loosening behavior in implant-supported zirconia restorations fabricated with various abutment designs. Methods: Thirty-six implant analogs were divided into three groups: (A) a one-piece hybrid abutment crown, (B) a two-piece hybrid zirconia abutment with a separated crown, (C) and a stock abutment with zirconia crown. Restorations were fabricated with CAD/CAM, bonded using a dual cure resin cement, and torqued to 35 Ncm to the analogs. The initial removal torque (RTV1) was measured, followed by thermal cycling and mechanical loading (500 cycles, 120,000 load cycles). The post-aging removal torque (RTV2) was measured and the torque loss percentage was calculated. Paired t-tests, ANOVA, and Tukey’s test were used (p < 0.05). Results: All groups demonstrated significant torque loss following aging (p < 0.001). Group A showed the highest torque loss (12.0%), while Groups B and C exhibited lower loss (7.6% and 7.9%, respectively). The between-group difference was statistically significant (p < 0.001), except for between Groups B and C (p = 0.53). Conclusions: Within the limitations of this in vitro study, the abutment configuration affected screw preload stability. The one-piece hybrid abutment crown showed greater torque loss after aging, while the two-piece and stock abutment designs maintained comparatively better stability. Further clinical studies are required to confirm these findings. Full article

The flow mechanism around a yawed cylinder is highly complex. While previous research has confirmed the limitation of the Independence Principle at high yaw angles, the specific flow phenomena beyond 20° yaw remain poorly understood, particularly concerning the spanwise development of the critical regime and the mechanism behind asymmetric surface pressure. Most studies have focused on spatially averaged forces or specific angles, lacking a systematic investigation of the inherent flow characteristics in the intermediate region of finite-length cylinders. To bridge this gap, the present study conducts a detailed wind tunnel test on a yawed cylinder across a wide range of yaw angles (0–60°). By analyzing the pressure distribution and aerodynamic forces in the mid-span region, this study yields the following core findings of universal significance: (1) As the yaw angle increases, the critical flow regime in the intermediate section occurs prematurely. This leads to a decrease in the Reynolds number at which the critical region begins, resulting in the formation of separation bubbles and consequent localized negative-pressure zones on either the upper or lower windward surface of the cylinder. (2) When the yaw angle β ≤ 17.4°, the mean drag and lift in the middle region resemble those of a straight cylinder. However, as the yaw angle increases further, the drag coefficient decreases beyond a certain critical Reynolds number, which itself decreases with increasing yaw angle. (3) At β = 0°, the circumferential mean pressure distribution is symmetric about the cross-sectional axis and remains largely uniform along the span. High yaw angles disrupt this symmetry and uniformity, leading to complex three-dimensional flow structures. These findings have critical implications for the design of structures like inclined bridge towers and cables under oblique winds. Full article

Background and Objectives: Parental fears and misconceptions about topical corticosteroids (TCS), known as TCS phobia, can hinder adherence and lead to poor eczema control in children. Despite its clinical relevance, few instruments capture this phenomenon using modern psychometric principles. This study aimed to develop and validate the Parental Topical Corticosteroid Phobia Scale (PTCPS), a brief tool grounded in Rasch measurement theory. Methods: A cross-sectional survey was conducted among 678 parents of children with eczema in Saudi Arabia. The five-item PTCPS was designed to reflect cognitive, emotional, and behavioral components of corticosteroid phobia. Rasch analysis using WINSTEPS assessed item fit, person and item separation and reliability, unidimensionality, and category functioning. Exploratory factor analysis (EFA) and principal component analysis (PCA) of residuals further evaluated structural validity. Results: All five items fit the Rasch model well (infit/outfit MnSq: 0.8–1.2), with strong item reliability (0.96) and clear item separation (4.67), indicating a well-defined item hierarchy. Person reliability was lower (0.40), suggesting limited precision in distinguishing between respondent levels. The scale showed functioning dichotomous response categories with no disordered thresholds. The eigenvalue of the first residual contrast (1.78) supported unidimensionality. Exploratory factor analysis confirmed a single-factor solution accounting for 53.0% of total variance, with substantial factor loadings (0.68–0.76) across all items, supporting structural coherence of the scale. Conclusions: The PTCPS is a psychometrically robust, unidimensional instrument for assessing TCS phobia in parents. Future research should validate its use across cultures, explore longitudinal stability, and assess its predictive value for treatment adherence. Full article

A rapid ultra-high-performance liquid chromatography method with diode-array (DAD) and tandem mass spectrometric (MS/MS) detection was developed and, for the first time, applied for the determination of potassium iodide in ophthalmic formulations. The approach is based on an indirect derivatization reaction in which iodide is oxidized by hydrogen peroxide to electrophilic iodine species that react with 4-hydroxybenzoic acid, forming 3-iodo-4-hydroxybenzoic acid as a stable and quantifiable product. Key reaction parameters, including oxidant concentration, temperature, and incubation time, were optimized to ensure selective mono-iodination and consistent analytical response. Chromatographic separation was performed on a C18-DE RP column using gradient elution with aqueous ammonium acetate and acetonitrile, while MS/MS detection was carried out in MRM mode under ESI(−) conditions. Both UHPLC–DAD and UHPLC–MS/MS methods were validated according to ICH Q2(R2), demonstrating linearity with r² ≥ 0.998, recovery values of 97.5–107.1%, and intraday/interday RSD values up to 3.7%. UHPLC–MS/MS provided higher sensitivity (LOD 37.7 ng/mL; LOQ 114 ng/mL), whereas UHPLC–DAD reached LOD and LOQ values of 24.9 and 75.4 µg/mL. Comparative analysis showed that DAD is suitable for routine quantification, while MS/MS allows lower detection limits and improved selectivity. The developed method offers a practical and reliable tool for the quality control of potassium iodide in ophthalmic formulations. Full article

The proliferation of power converters in modern energy production systems has led to increased harmonic content due to the commutation of active switching devices. This increase in harmonics contributes to lower system efficiency, reduced power factor, and consequently, a higher reactive power requirement. To address these issues, this paper presents both simulation and experimental results of various control strategies implemented on Parallel Voltage Source Inverters (PVSI) for harmonic mitigation. The proposed control strategies are categorized into direct and indirect control methods. The direct control techniques implemented include the instantaneous power method (PQ), the synchronous algorithm (DQ), the maximum principle method (MAX), the algorithm based on synchronization of current with the voltage positive-sequence component (SEC-POZ), and two methods employing the separating polluting components approach using a band-stop filter and a low-pass filter. The main innovation in these active power filter (APF) control strategies, compared to traditional or existing technologies, is the real-time digital implementation on high-speed platforms, specifically FPGAs. Unlike slower microcontroller-based systems with limited processing capabilities, FPGA-based implementations allow parallel processing and high-speed computation, enabling the execution of complex control algorithms with minimal latency. Additionally, the enhanced reference current generation achieved through the seven applied methods provides precise harmonic compensation under highly distorted and nonlinear load conditions. Another key advancement is the integration with Smart Grid functionalities, allowing IoT connectivity and remote diagnostics, which enhances system monitoring and operational flexibility. Following validation on an experimental test bench, these algorithms were implemented and tested on industrial APF prototypes powered by a standardized three-phase network supply. All control strategies demonstrated an effective reduction in total harmonic distortion (THD) and improvement in power factor. Experimental findings were used to provide recommendations for choosing the most effective control solution, focusing on minimizing THD and enhancing system performance. Full article

Deploying deep reinforcement learning (DRL) in safety-critical nuclear control is limited less by raw performance than by the absence of licensable, audit-ready evidence. We introduce a Deterministic Assurance Framework (DTAF) that converts controller behavior into licensing-grade proof by combining the following: (i) deterministic licensing gates tied to formal safety and performance limits (e.g., Total Time Unsafe (TTU) = 0; bounded Transient Severity Score (TSS); and minimum Grid Load-Following Index (GLFI)); (ii) a portfolio of adversarial stress tests representative of off-nominal operation; and (iii) a traceability and explainability package that renders every evaluated action auditable. The DTAF is demonstrated on a high-fidelity pressurized-water-reactor (PWR) simulation model used as a software-in-the-loop testbed. Three governor architectures are evaluated under identical, fixed scenarios: a curriculum-trained Soft Actor–Critic (SAC) agent, and Differential-Evolution-optimized Proportional–Integral–Derivative (PID-DE) and Fuzzy-Logic (FLC-DE) Controllers. Performance is assessed deterministically via gate-aligned metrics—TTU, TSS, GLFI, cumulative control effort (CE_sum), valve-reversal count (V_rev), and speed overshoot (OS_ω). Across the adversarial portfolio, the SAC controller meets the predeclared licensing gates in single-run evaluations, whereas the strong conventional baselines violate gates in specific high-severity cases; where all methods remain within the safe envelope, the SAC delivers a higher GLFI and lower CE_sum, with fewer reversals and reduced overshoot. All licensing conclusions derive from deterministic single-run tests; a small, fixed-seed check (three seeds with descriptive intervals) is reported separately as non-licensing supplementary analysis. By producing transparent, reproducible artifacts, the DTAF offers a regulator-oriented pathway for qualifying DRL controllers in grid-interactive nuclear operations. Full article