Search Results (1,006)

The development of realistic breast phantoms is critical for the evaluation of imaging systems and quantitative image analysis methods. In this work, breast samples derived from the same digital model were produced using 3D printing technology and evaluated for structural similarity and reproducibility. Four independently manufactured phantoms were imaged using mammography and breast tomosynthesis. Radiomic features were extracted from regions of interest in order to assess inter-phantom variability. The results showed very good agreement between the four printed phantoms. Most first-order and GLCM radiomic features exhibited very low inter-phantom variability, indicating consistent structural and intensity characteristics. Neighborhood-based texture features showed slightly higher variability, reflecting their sensitivity to local structural differences. Fractal and power spectrum analyses also confirmed the high structural similarity of the phantoms. These results indicate that the proposed manufacturing approach can produce reproducible breast imaging phantoms suitable for mammography and tomosynthesis imaging studies, with potential applications in imaging system evaluation and radiomic research. Full article

This study presents experimental modal analysis of an ultra-lightweight composite structure representative of UAV application and to evaluate the suitability of different testing approaches for reliable identification of its dynamics characteristics. The investigated structure is a winglet made of carbon fiber reinforced polymer (CFRP) with a lightweight foam core. The experiment was based on impact hammer excitation combined with triaxial accelerometer measurements. Modal tests were performed under three different boundary conditions: free–free suspension using elastic cords, free–free approximation using compliant foam support, and fixed conditions reflecting the operational mounting of the winglet. The results confirm that boundary conditions constitute the dominant factor governing the dynamic response. Transition from free–free to fixed support shifted the dominant bending modal frequency from 331.5 Hz (single-sided response) and 329.9 Hz (double-sided response) 421.2 Hz in the fixed configuration, demonstrating a frequency increase of nearly 27%. Reciprocity and double-sided measurements revealed measurable frequency deviations (e.g., 116.3 Hz to 117.6 Hz) attributed to accelerometer mass loading and geometric misalignment. The 1 g triaxial accelerometer mass was shown to be non-negligible relative to the modal mass of the structure, producing observable shifts in higher-order modes. Full article

Generative artificial intelligence (AI) is increasingly used in higher education as an interactive tutoring partner rather than a passive information tool. While AI offers opportunities to support learning, concerns remain regarding cognitive offloading, reduced engagement, and unreflective use. Although instructional scaffolding is a well-established design principle for supporting complex learning, its role in shaping cognitive and metacognitive processes in AI-supported settings remains underexplored. This quasi-experimental pre–post study examined how varying levels of scaffolding influence learning outcomes and motivational, cognitive and metacognitive processes during AI-tutored learning. A total of 175 first-semester students from two faculties and diverse academic backgrounds completed the same academic task within a four-hour university session under one of three conditions: (1) full scaffolding, including a structured prompting template based on the Goal–Context–Constraints (GCC) strategy, iterative refinement, and reflective guidance; (2) light scaffolding, including the GCC prompting template; or (3) no scaffolding template as the control condition. Measures included knowledge gain, motivation, cognitive load, critical thinking, and reflective use. Data were analysed using ANOVAs, ANCOVAs, regression models, and PROCESS moderation and mediation analyses. Across the conditions, students showed significant gains in knowledge, critical thinking, and reflective use, while motivation remained stable and intrinsic and extraneous cognitive load decreased; no significant differences between scaffolding conditions were observed. The scaffolding conditions did not produce significant interaction effects, although descriptive trends suggested higher gains in higher-order knowledge under scaffolded conditions. Overall, the findings suggest that short-term learning gains in AI-supported settings may not depend on scaffolding intensity alone, but rather on how learners engage with AI during the learning process. Full article

Against the backdrop of global coral reef degradation, benthic resource structure is shifting from coral dominance to turf algae and detritus-dominated epilithic algal matrix (EAM). As a typical detritivorous reef fish, Ctenochaetus striatus (Quoy & Gaimard, 1825) plays an important ecological role in regulating the functioning of degraded coral reef ecosystems. Using stable isotope analysis (δ¹³C and δ¹⁵N), this study systematically compared the trophic niche characteristics of different size classes of C. striatus across four reef habitats in the Xisha Islands, South China Sea, representing a gradient of disturbance (Qilianyu Island > Lingyang Reef > North Reef > Langhua Reef), in order to elucidate habitat-specific ontogenetic shifts and their adaptive features. The results showed that C. striatus from Qilianyu Island and Lingyang Reef exhibited overall higher δ¹⁵N values, suggesting an overall pattern consistent with stronger nitrogen enrichment at the more disturbed reefs, whereas individuals from Langhua Reef had significantly lower δ¹³C values, indicating a stronger reliance on offshore-derived carbon pathways. Across size classes, the trophic niche area (SEAc) and intraspecific trophic heterogeneity, measured as mean nearest neighbor distance and standard deviation of nearest neighbor distance, of populations from Qilianyu Island, Lingyang Reef, and North Reef generally decreased with increasing body size, revealing a pattern of trophic convergence toward core resources. In contrast, the Langhua Reef population exhibited a distinct expansion–contraction pattern, suggesting flexible resource use across developmental stages under conditions of low human disturbance and high resource heterogeneity. Although smaller size classes generally showed high probabilities of niche overlap among reefs, overlap declined markedly in the largest size class, with most values falling below 50%, indicating that resource assimilation strategies increasingly reflected reef-specific resource backgrounds. These findings demonstrate that ontogenetic trophic niche shifts in C. striatus are not fixed, but are highly dependent on local resource context and habitat conditions. In degraded reefs with simplified resource structure, individuals tend to converge on core resource spectra to maintain survival, whereas in healthier reefs with greater habitat heterogeneity, they tend to show greater variation in major food sources and resource use. This study provides a theoretical basis for coral reef ecological restoration. Full article

The identification of gifted students with learning disabilities (GLD) remains theoretically and methodologically contested. The present study examined cognitive and reading profiles of 150 Greek students in Grades 4–6, classified as gifted with learning disabilities (GLD) (n = 36), gifted (n = 31), or dyslexic of average intellectual ability (n = 83). Gifted classification was based on National Association for Gifted Children guidelines issued in 2018, using reasoning-based WISC-VIndices (FSIQ, GAI, EGAI, NVI, VECI ≥ 120), while learning disability was determined through formal multidisciplinary diagnosis. Cognitive performance was assessed with the WISC-V and reading with the standardized DADA battery (decoding, fluency, and comprehension). One-way ANOVAs and ROC analyses were conducted. GLD students demonstrated reasoning abilities and processing speed abilities comparable to gifted peers, but working memory deficits compared to gifted peers. In reading, GLD students showed decoding deficits like dyslexic peers and fluency impairments indistinguishable from them, yet significantly stronger comprehension. These findings reveal a differentiated literacy profile in which higher-order reasoning appears to support meaning construction despite persistent efficiency-based constraints in decoding and fluency. Overall, the results indicate that twice-exceptionality reflects a structurally uneven cognitive–academic configuration, underscoring the importance of multidimensional assessment approaches that simultaneously evaluate reasoning strengths and reading-specific vulnerabilities. Full article

Addressing climate change requires an understanding not only of science concepts but also the social, economic, and political factors that influence decision making. Thus, this study investigated the development of socio-scientific reasoning related to climate change action. This case study explored the six dimensions of socio-scientific reasoning (complexity, perspective-taking, inquiry, skepticism, affordance of science, and multiple perspective-taking) of twenty undergraduate students as they engaged with decision making about climate action. Data were collected from classroom worksheets reflecting small group decision making and individual student reflections. Data were analyzed using a rubric that categorized the level of students’ socio-scientific reasoning across the six dimensions. These categorizations were further supported by qualitative interpretation of students’ responses. The findings indicate strong performance in complexity and perspective-taking, while inquiry, skepticism, and the affordance of science were less consistently demonstrated. The study contributes to understanding how simulation-based learning can support the development of SSR and highlights the importance of structured pedagogical design in fostering higher order reasoning in climate education. Full article

Contemporary European societies face overlapping societal challenges—ecological degradation, immigration pressures, and widening economic inequality—which generate a pervasive climate of uncertainty affecting citizens’ perceptions of their own life conditions. This study investigates how social pessimism, conceptualised as a multidimensional orientation reflecting perceived threats across environmental, migratory, and distributive domains, relates to subjective financial insecurity at the individual level. Drawing on harmonised cross-national data from the CRONOS-II panel (N = 8993), covering eleven European countries, we construct a composite pessimism index and analyse its association with perceived financial strain using multivariate and multilevel regression models. Results demonstrate that individuals who express greater societal pessimism report significantly higher levels of financial insecurity, even after controlling for income, education, employment status, and country-level heterogeneity. This relationship is moderated by socioeconomic position; specifically, the pessimism–insecurity link is strongest among lower-income and less-educated groups, suggesting that material precarity and anticipatory anxiety compound one another. Cross-national analysis reveals substantial variation in effect magnitude, with the strongest associations observed in Hungary, Portugal, and the Czech Republic, and the weakest in Slovenia and Iceland. These findings contribute to the interdisciplinary understanding of how macro-level societal concerns permeate individual wellbeing, demonstrating that subjective economic vulnerability is shaped not only by objective circumstances but also by the broader socio-political climate in which citizens interpret their life situations. The results underscore the need for policies that address both material conditions and the affective dimensions of societal uncertainty in order to strengthen social cohesion and reduce perceived economic risk. Theoretically, we frame social pessimism as a formative composite capturing perceived threat to societal stability, offering an integrative perspective on how structurally distinct societal concerns converge to shape economic subjectivities. Full article

This study reports the structural, optical, and photocatalytic properties of Nd-doped Al₂O₃ nanoparticles synthesized via a high-temperature solid-state reaction method. The impact of varying Nd concentrations (1%, 2%, and 3%) on the host lattice was investigated through X-ray diffraction (XRD), which confirmed the successful integration of Nd³⁺ ions and revealed a concentration-dependent lattice expansion. Diffuse Reflectance Spectroscopy (DRS) demonstrated characteristic 4f-4f transitions of Nd³⁺, while Tauc plot analysis indicated a systematic blue shift in the optical bandgap from 4.5 eV to 4.63 eV with an increasing dopant content. The photocatalytic efficiency was evaluated through the degradation of Basic Fuchsin (BF) dye under UV irradiation. The Al₂O₃:3% Nd sample exhibited superior performance, achieving an 83% degradation efficiency within 160 min, following pseudo-first-order Langmuir–Hinshelwood kinetics (k_obs = 0.02428 min⁻¹). Photoluminescence (PL) studies further corroborated the structural integrity and defect dynamics, showing a significant enhancement in NIR emission (880–920 nm) at higher doping levels without reaching the concentration-quenching threshold. These results suggest that Nd-doped Al₂O₃ nanoparticles are highly effective for environmental remediation and optoelectronic applications. Full article

Selenium nanoparticles (SeNPs) represent promising bioactive agents due to their reduced toxicity and multifunctional biological properties. In this study, SeNPs were synthesized via an eco-friendly phytosynthesis approach using Curcuma longa extract, yielding curcumin-functionalized selenium nanoparticles (cur–SeNPs). The composites (cur–SeNPs), either in native extract form or isolated, were incorporated into siloxane hybrid matrices prepared by the sol–gel method from tetraethyl orthosilicate: dimethyldimethoxysilane precursors, with polyvinylpyrrolidone (PVP) as a structural modifier. The host matrices were differentiated by the ratios between the precursors of the siloxane network, 3:1 for CS0–CS4, respectively, 1:1 for CS5, modified with PVP in the case of CS2 and CS3. These were loaded with cur–SeNPs–T in the cases of CS1, CS2, CS5 or with cur–SeNPs for CS3 and CS4. FTIR, XRD, SEM, and EDX analyses confirmed the formation of amorphous siloxane networks with well-dispersed SeNPs (up to ~12 wt%). PVP incorporation generated ordered mesoporous structures, increasing total pore volume sixfold and enlarging the average pore diameter to 9.26 nm. Studies about selenium ion release demonstrate that mesoporosity significantly enhances diffusion-controlled release. Antimicrobial assays against Staphylococcus aureus, Escherichia coli, and Candida albicans reveal a synergistic effect between curcuminoids and SeNPs, particularly in matrices with higher nanoparticle loading. The sol–gel technique for obtaining hybrid materials is very versatile regarding the supports on which the resulting materials or the compounds hosted in these host networks can be deposited. The dynamics of the development of hybrid materials is also reflected in the multitude of applications in various fields such as bio-medical, electronics, agriculture or food. Results obtained in this work highlight the potential of the developed systems for antimicrobial coatings on glass substrates and targeted delivery applications. Full article

Background: In this study, type B gelatin was extracted from Oreochromis niloticus scales under hydrothermal conditions at 60 °C to evaluate the effect of ultrasound-assisted pretreatment on its structural, physicochemical, thermal, and functional properties. Methods: Gelatin obtained with and without ultrasound pretreatment was systematically characterized through molecular weight analysis, proteomic profiling, size determination, surface morphology, proximate composition, thermal behavior, and gelation-related functional properties in order to assess the influence of the extraction method on gelation performance. Results: Ultrasound pretreatment slightly increased gelatin yield from 1.46 to 1.70%, indicating enhanced collagen solubilization. Proteomic analysis confirmed the predominance of fibrillar collagen proteins in both samples, although differences in protein distribution were observed. Furthermore, weight-average molecular weight analysis revealed a reduction from 212.3 ± 11.8 to 170.9 ± 13.2 kDa in the ultrasound-treated sample, suggesting partial fragmentation of collagen chains induced by cavitation effects. Structural modifications were also reflected in increased porosity and surface changes, contributing to improved colloidal stability. However, these changes significantly affect the functional behavior of the gelatin. Ultrasound-treated sample exhibited limited gel-forming capacity and failed to form stable gels at the evaluated concentration, despite complete dissolution. In contrast, gelatin extracted without ultrasound treatment retained higher-molecular-weight fractions and formed stable gels at both 5 and 10% (w/w). Thermal and spectroscopic analyses suggested that the fundamental collagen structure was preserved in both samples, although differences were observed in thermal degradation behavior. Conclusions: These results highlight the importance of controlling ultrasound-assisted extraction conditions to balance collagen recovery with the preservation of molecular integrity required for gelation, providing insights for the development of sustainable fish-derived biomaterials for pharmaceuticals and biomedical applications. Full article

Objective: To evaluate the utility of synovial iron quantification using Magnetic resonance imaging (MRI) in assessing structural joint damage in the knee of patients with rheumatoid arthritis (RA). Methods: This cross-sectional study employed a two-stage design. In the initial comparative stage, 6 patients with RA and 5 patients with osteoarthritis (OA) were recruited to compare synovial R2* values, a metric derived from iterative decomposition of water and fat with echo asymmetry and least-squares estimation quantitation (IDEAL-IQ) MRI sequences representing synovial iron content. Following this, the RA cohort was expanded to a total of 51 patients to investigate the association between R2* values and clinical parameters, including disease activity and bone erosion. Synovial fluid iron levels were measured with an Iron Assay Kit and synovial iron deposits were semi-quantified via Prussian blue staining. Associations between R2* and clinical and laboratory parameters, including inflammatory factors and joint damage indices, were analyzed using Spearman’s rank correlation. Univariate and multivariate ordered logistic regression models were employed to identify factors associated with bone erosion severity. An R2*-based nomogram was developed and validated using receiver operating characteristic (ROC) analysis and calibration curves. Results: Synovial R2* values were significantly higher in RA patients than those with osteoarthritis (53.66 S⁻¹ vs. 31.38 S⁻¹, p < 0.05), consistent with Prussian blue staining results. While synovial R2* values showed no significant correlation with systemic iron metabolic markers, inflammatory indicators, or the Disease Activity Score 28, they were positively correlated with bone erosion severity (ρ = 0.500, p < 0.001) and negatively associated with the joint space width (ρ = −0.307, p < 0.05). Multivariate analysis identified R2* as an independent indicator linked to bone erosion extent (OR = 2358.336, p < 0.001). The R2*-based nomogram demonstrated good discriminative performance. (AUC = 0.83). Conclusions: The R2* value derived from IDEAL-IQ MRI is a reliable tool for quantifying synovial iron and may represent a promising non-invasive imaging biomarker reflecting bone erosion in RA patients. Full article

Desertification is one of the main threats to high Andean ecosystems, particularly in arid and semi-arid regions subject to increasing climatic and anthropogenic pressures. This study evaluated the spatial-temporal dynamics of desertification in the province of Candarave (Tacna, Peru) by integrating the Remote Sensing-based Desertification Index (RSDI), constructed from a principal component analysis incorporating four biophysical indicators: vegetation greenness, surface moisture, soil grain size, and fraction of solar radiation reflected (albedo), derived from Landsat 5 and 8 satellite images processed in Google Earth Engine. Temporal trends were analyzed using the Mann–Kendall test, while system stability was evaluated using the coefficient of variation, allowing different degrees of stability and environmental degradation to be characterized during the period 2010–2025. The results show that moderate and severe desertification classes predominate in higher altitude areas, covering approximately 92% of the study area, and are characterized by insignificant to weakly significant negative trends associated with high to relatively high temporal volatility. In contrast, stable areas with no significant changes represent 5.3% of the territory, while restoration processes occupy a small proportion, close to 2.7%. The high variability observed in the high Andean sectors is mainly linked to the interaction between reduced water availability, climate variability, and extreme events, as well as anthropogenic pressures, particularly overgrazing and aquifer exploitation. This multitemporal analysis allows us to anticipate the evolution of desertification and highlights the need to strengthen conservation planning in order to reduce the degradation of strategic high Andean ecosystems in the Tacna region. Full article

The wildfires in the vicinity of the power transmission corridors are famous for their sudden occurrence, rapid growth, and susceptibility to interference from fire-like interferences at night, which can easily lead to line discharge and trip accidents, thus affecting the safe operation of the power system. In order to address the issue of the high false alarm rate and poor generalization performance of wildfire image recognition in complex power transmission corridor environments, a wildfire image recognition method based on an improved AlexNet is proposed in this paper. The proposed method improves the description of flame and smoke properties at different scales by designing a reparameterized multi-scale feature extraction structure, and effectively alleviates the influence of strong light reflection and fire-like interference at night by using lightweight multi-scale attention and hybrid pooling attention mechanisms. A wildfire image dataset is constructed based on 1246 on-site images of the power transmission corridor captured by a visual monitoring device and 600 wildfire images downloaded from the internet, and tested in real-world imbalanced distribution scenarios. The experimental results show that the proposed method can recognize wildfire images with an accuracy of 96.9% and an F1 value of 94.9% on the test dataset, which is much higher than that of the original AlexNet, and has a strong ability to adapt to cross-dataset tests. The research work can provide technical support for online monitoring and operation and maintenance of wildfires in power transmission corridors. Full article

This study investigated the surface characteristics and wettability behaviour of grey poplar (Populus × canescens) compared with spruce (Picea abies) in order to evaluate its potential as an alternative raw material for bonded structural wood products. Surface roughness was analysed on freshly planed radial surfaces using amplitude and functional roughness parameters, complemented by multivariate factor analysis and dynamic contact angle measurements. The results showed that grey poplar sapwood exhibited roughness values comparable to spruce (R_a ≈ 6–7 μm; R_z ≈ 35–40 μm). Grey poplar heartwood showed slightly higher roughness and greater variability, which can be attributed to its heterogeneous anatomical structure characterised by larger vessel elements and higher extractive content. Hybrid roughness parameters indicated favourable bonding-related surface characteristics in sapwood due to lower R_pk values, suggesting fewer protruding fibres, while higher R_vk values reflected the diffuse-porous anatomical structure of poplar. Static contact angle measurements revealed higher initial values for grey poplar (37.9° for heartwood and 41.9° for sapwood) compared with spruce (31.7°), indicating lower initial wettability with polar liquids. However, dynamic measurements demonstrated faster early-stage spreading in grey poplar heartwood (Δθ = 26.1° within the first second) compared with sapwood (16.8°) and spruce (17.5°), suggesting that vessel-driven capillary uptake may facilitate liquid penetration once wetting begins. Overall, the results indicate that grey poplar—particularly its sapwood fraction—exhibits surface characteristics comparable to spruce after planing. Despite slightly lower initial wettability, its spreading behaviour and surface morphology indicate favourable conditions for adhesive interaction. These findings support the potential use of grey poplar as an alternative raw material for laminated structural products such as glulam or bonded panels, provided that adhesive application parameters are properly adjusted. Full article

Background: Trastuzumab is a blockbuster monoclonal antibody that has revolutionized the treatment of HER2-positive breast and gastric cancers. With the increasing availability of biosimilar monoclonal antibodies in clinical practice, independent verification of biosimilarity using products sampled from a real-world supply chain is important to assure clinicians and the patients to use these products confidently. Objective: The aim of this study is to assess the biosimilarity of AryoTrust, a trastuzumab biosimilar, in comparison with the reference product Herceptin. AryoTrust and Herceptin products were randomly withdrawn from Iraqi hospitals to reflect medicines administered in real clinical settings. Methods: AryoTrust and Herceptin were compared using an extensive set of orthogonal analytical techniques which included SDS-PAGE, ion-exchange chromatography, capillary isoelectric focusing, peptide mapping, N-glycan profiling, circular dichroism, differential scanning calorimetry, and surface plasmon resonance. In addition to these teste, functional comparability was also tested using an HER2-dependent cell-based proliferation inhibition bioassay. Results: The results showed that both products have highly comparable profiles in all assessed attributes. The analysis showed similar molecular integrity and purity, identical primary structure, comparable charge heterogeneity, similar isoelectric points (pI) of the main isoform, close glycosylation patterns (mainly, by core-fucosylated complex-type glycans), similar higher-order structural features, and thermal stability. The receptor binding studies exhibited comparable binding affinities with Fcγ receptors and FcRn. Finally, the cell-based bioassay revealed comparable dose–response curves with similar EC₅₀ values and relative potency. Conclusions: The integrated analytical and functional data support the biosimilarity of AryoTrust to the reference product Herceptin, which has been marketed and used in Iraq. This study provides real-world scientific evidence supporting confidence in the quality and comparability of this trastuzumab biosimilar and reduces any doubt in the product and at the same time emphasizes the value of independent post-marketing biosimilarity assessments. Full article