Search Results (13,708)

Objectives: We aimed to develop and validate a per-cycle prediction model for in vitro fertilization (IVF) success using only preprocedural clinical variables available at the first consultation. Methods: We retrospectively analysed 1243 IVF/ICSI cycles (University of Szeged, 21 January 2022–12 December 2023). An Extreme Gradient Boosting (XGBoost version 1.7.7.1) classifier was trained on 14 baseline predictors (e.g., female age, AMH, BMI, FSH, LH, sperm concentration/motility, and infertility duration). A parsimonious 9-variable model was derived by feature importance. Model performance was assessed on the untouched test set and, as a final step, on an independent same-centre external validation cohort (n = 92) without re-fitting or recalibration. Results: The 9-variable model achieved an AUC of 0.876 on the internal test set, with an accuracy of 81.70% (95% CI 76.30–86.30%), sensitivity of 75.60%, specificity of 84.40%, PPV of 68.60%, and NPV of 88.50%. In external validation, the model maintained strong performance with an accuracy of 78.30%, confirming consistent discrimination on an independent same-centre cohort. Female age was the dominant high-impact feature, while AMH and BMI acted as “workhorse” predictors, and male factors added incremental value. Conclusions: IVF outcome can be predicted at the first visit using routinely collected preprocedural data. The model showed consistent discrimination internally and in external validation, supporting its potential utility for early, individualized counselling and treatment planning. Full article

Due to their compact dimensions, high torque density, high efficiency, and superior flux-weakening capabilities, permanent magnet synchronous machines with tooth-coil winding (TC-PMSMs) are highly suitable for low-power electric transportation applications. This study incorporates the actual duty cycle of an electric motorcycle in the optimization of the slot number for the drive machine. The proposed methodology addresses the shortcomings of conventional design strategies, which typically consider only a limited set of operating points, leading to suboptimal round-trip efficiency under real driving conditions. Firstly, the influence of slot number on torque output, electromagnetic losses, and flux-weakening performance is examined for 10-pole TC-PMSMs using finite element analysis. Subsequently, the optimal slot number is identified by integrating the real duty cycle of the drive motor into the evaluation. To verify the accuracy and effectiveness of the analytical results and design approach, prototypes of stator assemblies with varying slot numbers were fabricated and experimentally tested. Full article

The Tibetan Plateau is a globally critical climate-sensitive and ecologically fragile region. Vegetation phenology serves as a key indicator of ecosystem responses to climate change and simultaneously influences regional carbon cycling, water regulation, and ecological security. However, systematic quantitative assessments of phenological responses under the combined effects of multiple climate factors remain limited. This study integrates multi-source remote sensing data (MODIS MCD12Q2) and ERA5-Land meteorological data from 2001 to 2023, leveraging the Google Earth Engine (GEE) cloud platform to extract key phenological metrics, including the start (SOS) and end (EOS) of the growing season, and growing season length (GSL). Sen’s slope estimation, Mann–Kendall trend tests, and partial correlation analyses were applied to quantify the independent effects and spatial heterogeneity of temperature, precipitation, solar radiation, and evapotranspiration (ET) on GSL. Results indicate that: (1) GSL on the Tibetan Plateau has significantly increased, averaging 0.24 days per year (Sen’s slope +0.183 days/yr, Z = 3.21, p < 0.001; linear regression +0.253 days/yr, decadal trend 2.53 days, p = 0.0007), primarily driven by earlier spring onset (SOS: Sen’s slope −0.183 days/yr, Z = −3.85, p < 0.001), while autumn dormancy (EOS) showed limited delay (Sen’s slope +0.051 days/yr, Z = 0.78, p = 0.435). (2) GSL changes exhibit pronounced spatial heterogeneity and ecosystem-specific responses: southeastern warm–wet regions display the strongest responses, with temperature as the dominant driver (mean partial correlation coefficient 0.62); in high–cold arid regions, warming substantially extends GSL (Z = 3.8, p < 0.001), whereas in warm–wet regions, growth may be constrained by water stress (Z = −2.3, p < 0.05). Grasslands (Z = 3.6, p < 0.001) and urban areas (Z = 3.2, p < 0.01) show the largest GSL extension, while evergreen forests and wetlands remain relatively stable, reflecting both the “climate sentinel” role of sensitive ecosystems and the carbon sequestration value of stable ecosystems. (3) Multi-factor interactions are complex and nonlinear; temperature, precipitation, radiation, and ET interact significantly, and extreme climate events may induce lagged effects, with clear thresholds and spatial dependence. (4) The use of GEE enables large-scale, multi-year, pixel-level GSL analysis, providing high-precision evidence for phenological quantification and critical parameters for carbon cycle modeling, ecosystem service assessment, and adaptive management. Overall, this study systematically reveals the lengthening and asymmetric patterns of GSL on the Tibetan Plateau, elucidates diverse land cover and climate responses, advances understanding of high-altitude ecosystem adaptability and climate resilience, and provides scientific guidance for regional ecological protection, sustainable management, and future phenology prediction. Full article

Optimal mechanical parameters for successful bone-healing remain unclear despite their critical influence on fracture outcomes, and the timing of post-surgery mobilization is still controversial despite many clinical observations and pre-clinical studies. In this bioreactor in vitro work, we investigate the effect of fundamental parameters such as timing, duration, and frequency of mechanical stimulation on the endochondral bone-healing paths, specifically on the hypertrophic chondrocyte differentiation of naïve human mesenchymal stromal cells (hMSCs). Human MSCs encapsulated in Gelatin-Methacryloyl hydrogels (GelMa) were subjected to three different 10% strain protocols: P1 (168 long-break cycles spread over 14 days), P2ce (cycle equivalent: 168 short-break cycles condensed in 42-min stimulation followed by 14 days free swelling), and P2te (time equivalent—14 days continuous stimulation, 80′640 short-break cycles). In the free-swelling control group, samples were cultured for 14 days without any mechanical stimulation. Our results confirmed that 10% strain induces a robust hypertrophic chondrocyte differentiation of naïve MSCs in all three tested protocols, as demonstrated by enlarged cell size, rounded morphology, robust upregulation of hypertrophic markers (COL10A1, MMP13, RUNX2, ALP), and reduced glycosaminoglycan production. Of particular interest, we show that P2ce (early short stimulation) was as effective as the two extended stimulation protocols, suggesting that initial mechanical signals are sufficient to trigger cell differentiation toward a hypertrophic chondrocyte phenotype that continues even after stimulation ceases. These in vitro findings provide crucial insights into the cellular basis of endochondral ossification during the early phase of loading and show a beneficial long-term effect of early mechanical stimulation. By demonstrating that the cellular mechanobiology of hypertrophic differentiation responds to brief early stimulation, our findings provide a scientific foundation to guide future in vivo investigations on how rehabilitation protocols could influence fracture healing. Full article

Tannin foams are polymeric, porous materials produced from plant tannins, with good thermal insulation and fire-retardant properties. Although research has mainly concentrated on usage of condensed tannins (CTs), interest in a second group, hydrolyzable tannins (HTs), is growing. This study evaluated the usability of glyoxal as a single crosslinker for condensed and hydrolyzable tannins in foams created through mechanical agitation, using various ratios of chestnut (HT) and quebracho (CT) tannins. Glyoxal could react with chestnut tannin, but foams with only chestnut collapsed before hardening due to its slow reactivity, with 70% chestnut as the maximum viable content. Increasing the chestnut tannin amount reduced the foamability and compression strength, resulting in higher density and increased pore size. At a similar density (~210 kg m⁻³), the 70%-HT foam reached only one-third the compressive strength of the pure CT foam (0.22 vs. 0.61 MPa), while the pure CT foam showed a smaller mean pore size (189 vs. 365 µm) despite its lower mean density (208 vs. 241 kg m⁻³). The fire resistance and thermal conductivity appeared unaffected by the tannin type and instead depended on the foam density, with thermal conductivities ranging from 56 to 71 mW/(m·K). Leaching tests showed a slight increase in leaching for formulations with higher chestnut tannin contents, with 15% to 24% of acid recovered after the leaching cycle. The ¹³C-NMR analysis revealed the glyoxal crosslinks at the free position of the A-ring in CTs and at the free ortho ones of the gallic/ellagic moieties in HTs. Overall, this study demonstrated that tannin foams can be produced using glyoxal as a single crosslinker, allowing for up to 70% substitution of the condensed tannin component in the formulation. Full article

Objective: Evaluating the in vitro marginal adaptation of conventional, flowable and restorative bulk-fill resin composites placed in large class II cavities with supra- and sub-gingival margins, using a bulk-fill or layering approach, before and after thermo-mechanical loading (TML) simulating parafunctional forces. A total of 40 prepared teeth were divided and assigned to each of the five experimental groups. In group 1, restorations were made of layered high-viscosity conventional composite (Tetric EvoCeram); in groups 2 and 3 restorations were made of a high-viscosity bulk-fill composite (Tetric Powerfill) applied in one (group 2) or three layers (group 3); in groups 4 and 5 restorations were made of a flowable bulk-fill composite (SDRflow) applied in one (group 4) or two layers (group 5), underneath a layer of high-viscosity composite (Ceram-X Spectra ST). The same adhesive (OptiBond FL) was used in all groups. All specimens were submitted to a TML comprising a loading phase of 250,000 cycles at 100 N combined to 1675 thermal cycles (5 to 55 °C). The proximal tooth-restoration interfaces were analyzed quantitatively by SEM, prior and after TML. Results: Repeated measures ANOVA followed by Fisher’s LSD (Least Significant Difference) post hoc tests served for comparing inter-group marginal adaptation percentages between the pre- (T0) and post- (T1) loading conditions and intra-group marginal adaptation percentages. The lowest pre-loading values were for the cervical dentin adaptation ranging from 94.79% (SDRflow layered) to 66.06% (Tetric Powerfill layered) while the post-loading values of continuous cervical dentin adaptation varied from 61.20% (SDRflow layered) to 33.36% (SDRflow Monolayer). TML with higher axial forces led to a marked reduction in continuous adaptation at enamel or dentin margins in all groups. Overall, the low-viscosity bulk-fill SDRflow layers showed the best behavior while other products showed varying levels of degradation. Conclusions–Clinical significance: Simulated bruxism loading conditions induced severe marginal adaptions of class II composite restorations, which could potentially impact their lifespan. Full article

Ultra-high-performance concrete (UHPC) has been widely utilised in strengthening and rehabilitating conventional normal concrete (NC) structures due to its exceptional mechanical properties and durability. However, in cold climates, the interfacial bond between UHPC and NC is susceptible to degradation under freeze–thaw cycles, potentially compromising the composite action and long-term performance of strengthened structures. This study systematically investigated the shear behaviour of a UHPC-NC interface with planted reinforcement subjected to various freeze–thaw conditions. The experiments were conducted considering different numbers of freeze–thaw cycles (0, 20, 40, 60, 80, and 100) and salt solution concentrations (0%, 3.5%, and 5%). Direct shear tests were performed to evaluate interfacial failure modes, mass loss, and shear strength degradation. Results identified three characteristic failure modes: adhesive debonding at the interface, mixed failure involving both the interface and the NC substrate, and crushing failure within the NC substrate. Specimens exposed to 3.5% salt solution experienced the most significant deterioration, exhibiting a 35% reduction in shear strength after 100 freeze–thaw cycles. Normally, lower salt concentrations were found to induce greater interfacial damage compared to higher concentrations. The study underscores the importance of increasing the embedment depth of the planted reinforcement to alleviate stress concentration and enhance interfacial durability in freeze–thaw environments. Full article

Air cycle systems, once largely replaced by vapour-compression technologies due to efficiency concerns, are now re-emerging as a viable and sustainable alternative for highly dynamic thermal applications and excel in ultra-low temperature. By using air as the working fluid, these systems eliminate the need for synthetic refrigerants and comply naturally with evolving environmental regulations. This study presents the conceptual design and simulation-based analysis of a novel air cycle machine developed for advanced automotive testing environments. The system is intended to replicate a wide range of climatic conditions—from deep winter to peak summer—through the use of fast-responding turbomachinery and a flexible control strategy. A central focus is placed on the radial turbine, which is designed and evaluated using a modular, open source framework that integrates geometry generation, off-design CFD simulation, and performance mapping. The study outlines a potential operating strategy based on these simulations and discusses a control architecture combining lookup tables with zone-specific PID tuning. While the results are theoretical, they demonstrate the feasibility and flexibility of the proposed approach, particularly the turbine’s role within the system. Full article

Chlorobenzoic acids (CBAs) are a group of chlorinated persistent environmental pollutants with hard biodegradability, high water solubility, and well-documented carcinogenic and endocrine-disrupting properties. Electrocatalytic hydrodechlorination (ECH) is a highly efficient method under mild conditions without harmful by-products, but the ECH process commonly requires adding precious metal catalysts such as palladium (Pd). To address the economic constraints and more effective utilization of Pd, a palladium/manganese dioxide (Pd/MnO₂) composite catalyst was developed in this study by chemical deposition. This method utilized the excellent electrochemical activity of MnO₂ as a carrier as well as the hydrogen storage and activation capacity of Pd. The test showed the optimal Pd loading was 7.5%, and the removal percent of 2,4-dichlorobenzoic acid (2,4-DCBA), a typical CBA, reached 97.3% using 0.5 g/L of Pd/MnO₂ after 120 min of electrochemical reaction. Under these conditions, the dechlorination percent can also be as high as 89.6%. A higher current density enhanced the dechlorination efficiency but showed the lower current utilization efficiency. In practical applications, current density should be minimized on the premise of compliance with the water treatment requirement. Mechanistic studies showed that MnO₂ synergistically promoted hydrolysis dissociation and hydrogen spillover and facilitated Pd-mediated adsorption of atomic hydrogen (H*) for dehydrogenation of 2,4-DCBA. The presence of MnO₂ can effectively disperse the loaded Pd and reduce the amount of Pd via the above process. The catalyst exhibited excellent stability over multiple cycles, and the 2,4-DCBA removal could still reach more than 80% after the five cycles. This work establishes electrocatalytic strategies for effectively reducing Pd usage and maintaining high removal of typical CBAs to support CBA-related water treatment. Full article

Background/Objectives: Maintaining independent mobility among older adults requires complex cognitive and physical health and is influenced by various health-related factors. This study sought to examine the relationship between health-related factors and driving among community-dwelling older adults by comparing the health status of currently driving individuals and those who have ceased driving. Methods: A secondary data analysis was conducted using the 2023 Korean Elderly Survey, collected between 4 September and 12 November 2023. A total of 4114 individuals aged 65 years or older were included. Statistical analyses were performed using chi-square tests, independent t-tests, and weighted binary logistic regressions via IBM SPSS for Windows. Results: Significant health-related factors for driving cessation included having ≥2 chronic diseases (OR = 1.22, p = 0.041), diagnosed depression (OR = 3.64, p = 0.030), Instrumental Activities of Daily Living dependency (OR = 1.67, p = 0.001), visual discomfort (OR = 1.18, p = 0.048), depression risk (OR = 1.34, p = 0.015), suspected cognitive impairment (OR = 1.73, p < 0.001), and poor self-rated health (OR = 1.21, p = 0.029). None of the participants with Parkinson’s were currently driving, whereas polypharmacy (≥5 medications) was not statistically significant (OR = 0.77, p = 0.222). Chronic diseases that may affect driving were also not statistically significant. Conclusions: This study highlights the fact that older drivers may have difficulty recognizing health-related risks that affect driving. To support safe mobility, it is essential to implement a health-centered assessment of driving fitness, including an appropriate evaluation cycle, and promote continuous education to raise awareness among older adults. Full article

Modular shipbuilding, as a cutting-edge ship construction paradigm, enables parallel manufacturing across workshops and stages—a core advantage that significantly shortens the total shipbuilding cycle, making it pivotal for modern shipyards to enhance productivity. However, this mode decomposes the integrated shipbuilding project into a large number of interdependent sub-activities spanning three key stages (fabrication, logistics, and assembly). Further, the duration of these sub-activities is inherently uncertain, primarily due to the extensive manual operations, variable on-site conditions, and supply chain fluctuations inherent in shipbuilding. These characteristics collectively pose a formidable challenge to project planning that pursues both high efficiency and low cost. To address this challenge, this paper proposes a Strategy-Group Evolution algorithm. First, the modular shipbuilding process scheduling problem is mathematically formulated as a resource-constrained three-stage multi-objective optimization model, where triangular fuzzy numbers are employed to characterize the uncertain sub-activity durations. Second, a two-layered Strategy-Group Evolution algorithm is designed for solving this model: the inner layer comprises 12 practical priority rules tailored to modular shipbuilding’s multi-stage features, while the outer layer adopts a genetic algorithm-based evolution policy to schedule and optimize the assignment of inner-layer rules to activity groups. The core of the Strategy-Group Evolution algorithm lies in dynamically assigning suitable strategies to different activity groups and evolving these assignments toward optimality—this avoids the limitation of a single priority rule for all stages, thereby facilitating the search for global optimal solutions. Finally, validation tests on real cruise ship construction projects and benchmark datasets demonstrate the efficacy and superiority of the proposed Strategy-Group Evolution algorithm. Full article

Background: Colorectal cancer (CRC) is the second leading cause of cancer-related mortality worldwide. The search for effective, new antineoplastic drugs with fewer side effects for the treatment of CRC continues, with marine-derived compounds emerging as promising candidates. Objectives: This study investigates the anticancer potential of Frondanol, a nutraceutical derived from the Atlantic Sea cucumber Cucumaria frondosa, known for its potent anti-inflammatory properties. Methods: Two human CRC cell lines, Caco-2 and HT-29, were used to test the effects of Frondanol using various in vitro approaches. Results: Frondanol significantly inhibited cell viability in a dose- and time-dependent manner. At a 1:10,000 dilution, viability decreased to around 30% in Caco-2 and 20% in HT-29 after 24 h, dropping to nearly 5% at 48 h. Furthermore, a clonogenic assay showed around 50% reduction in colony formation in both cell lines. Flow cytometry-based Annexin V staining revealed that Frondanol increased early apoptosis to ~5.2% in Caco-2 and ~9.4% in HT-29 cells, while cell cycle analysis showed accumulation of the sub G0 (apoptotic) phase increasing from 1.5% to 14.7% (Caco-2) and from 1.9% to 23.8% (HT-29). At the molecular level, Frondanol treatment significantly decreased anti-apoptotic protein B-cell lymphoma (Bcl)-2 expression while increasing the expression of the proapoptotic protein Bcl-2-associated X-protein. Additionally, Frondanol markedly induced cytochrome c release from the mitochondria and activated caspase-9, caspase-7, and caspase-3 after treatment, alongside cleavage of the caspase-3 substrate poly (ADP-ribose) polymerase. Frondanol inhibited 5-lipoxygenase activity, further contributing to its anticancer effects. Conclusions: In conclusion, Frondanol inhibits CRC cell proliferation and induces apoptosis through the mitochondrial pathway in vitro, suggesting that it is a potential nutraceutical for the prevention of human colorectal cancer or a valuable source of anticancer compounds. Full article

This study investigates the mechanical behavior and fatigue performance of orthotropic steel bridge decks, with a focus on rib-to-deck welded connections and the impact of geometric symmetry on stress distribution. Two full-scale models with full-penetration butt welds were tested under static compression loads, yielding failure forces of 27 kN (experimental) and 26 kN (analytical), with only a 3% difference. Finite element simulations using ANSYS 16.1 validated these results and enabled parametric studies. Rib plate thicknesses ranging from 5 mm to 9 mm were analyzed to assess their influence on stress distribution and deformation. The geometric ratio h′/tr, which reflects the symmetry of the trapezoidal rib web, was found to be a critical factor in stress behavior. At h′/tr = 38 (tr = 7 mm), compressive and tensile stresses are balanced, demonstrating a symmetric stress field; at h′/tr = 33 (tr = 8 mm), and fatigue performance at the RDW root drops by 47%. Increasing h′/tr improves fatigue life by increasing the number of load cycles to failure. Stress contours revealed that compressive stress concentrates in the rib plate above the weld toes, while tensile stress localizes at the RDW root. The study highlights how symmetric geometric configurations contribute to balanced stress fields and improved fatigue resistance. Multiple linear regression analysis (SPSS-25) produced predictive equations linking stress values to applied load and geometry, offering a reliable tool for estimating stress without full-scale simulations. These findings underscore the importance of optimizing h′/tr and leveraging structural symmetry to enhance resilience and fatigue resistance in welded joints. This research provides practical guidance for improving the design of orthotropic steel bridge decks and contributes to safer, longer-lasting infrastructure. Full article

Fatigue damage is critical for 0Cr17Ni4Cu4Nb stainless-steel components that may operate near yield under stress-controlled cycles and occasional peak holds. This work investigates the cyclic response of 0Cr17Ni4Cu4Nb stainless-steel under near-yield-stress-controlled (NYSC) loading and proposes a unified damage framework that bridges monotonic ductile fracture, near-yield stress-controlled fatigue. Building on the Enhanced Lou-Yoon model, an elastic-damage term is introduced and embedded within a continuum damage mechanics framework, allowing elastic (sub-yield) and plastic (post-yield, Ultra-Low-Cycle-Fatigue/Low-Cycle-Fatigue (ULCF/LCF)) damage to be treated in a unified, path-averaged stress-state description defined by stress triaxiality and the Lode parameter. Five stress-controlled test groups are examined, with applied load amplitudes from 20.6 to 25.1 kN (equivalent stress amplitudes 858~1044 MPa) yielding fatigue lives ranging from 32 to 13,570 cycles. The extended model captures the evolution of damage origin mechanisms from elasticity-dominated to plasticity-dominated as loading severity increases, demonstrating a unified elastic-plastic damage modeling approach. As a result, it accurately predicts fatigue lives spanning two orders of magnitude with an average absolute percentage error of approximately 14.5% across all conditions. Full article

Multiaxial low-cycle fatigue (MLCF) behavior of laser powder bed fused (L-PBF) Ti-6Al-4V was systematically investigated with four building direction (BD) in this paper. Proportional and non-proportional strain-controlled MLCF tests characterized cyclic softening and fracture mechanisms. L-PBF Ti-6Al-4V exhibits three-stage cyclic softening with occasional initial hardening, while non-proportional softening predominates, contrasting with conventional titanium alloys. Macro-micro characterization reveals that defect density and cleavage morphology strongly influence fatigue performance across BD. Fatigue life was predicted using analytical models (FS and KBMP) and a hybrid physics- and data-driven VAE-ANN model. While the KBMP model improves predictions over FS, both fail to fully account for BD effects. Incorporating macro-micro features, the VAE-ANN model achieves highly accurate MLCF life predictions within 10% error. These results highlight the critical roles of BD and microstructural characteristics in governing the MLCF behavior of L-PBF Ti-6Al-4V. Full article