Search Results (8,179)

Compounds containing electron-withdrawing dicyanopyrazine and 1,2,5-chalcogenadiazole fragments are promising for the design of magnetic and optoelectronic materials. In this paper, bis([1,2,5]thiadiazolo)[3,4-f:3′,4′-h]quinoxaline-8,9-dicarbonitrile was prepared via Körner–Hinsberg condensation of benzo[1,2-c:3,4-c′]bis([1,2,5]thiadiazole)-4,5-dione with 2,3-diaminomaleonitrile in the presence of catalytic amounts of TsOH in refluxing ethanol. The structure of the newly synthesized compound was established via elemental analysis, mass spectrometry, ¹³C NMR, and IR spectroscopy. Full article

Quality management in mega construction projects is increasingly supported by digital technologies, yet quality information often remains fragmented across inspection systems, reality-capture platforms, Building Information Modelling (BIM) environments and enterprise systems. This fragmentation limits traceability, delays corrective actions and weakens the connection between quality performance, contractual obligations and financial accountability. This study develops a closed-loop digital QA/QC framework that integrates BIM, mobile field inspection, reality capture, artificial intelligence (AI) augmentation and enterprise resource planning (ERP) within a unified governance architecture. Following a Design Science Research approach, the study proposes a seven-layer framework linking quality events to procurement, financial control, and project-management processes while supporting role-based decision-making through data democratisation mechanisms. The framework extends conventional ERP-enabled quality management by explicitly incorporating procurement (MM) and financial-control (FI/CO) functions, including supplier-quality management, cost-of-poor-quality tracking and quality-linked payment governance. An illustrative project scenario and sensitivity analysis are used to demonstrate the application of the proposed KPI and evaluation structure. By treating integration as the primary design objective, the framework provides a foundation for enterprise-wide digital quality management, lifecycle information continuity and digital-twin readiness in mega construction projects. The contribution itself is evaluated through an illustrative Design Science Research demonstration and an assumption-bounded sensitivity analysis rather than through field data, with future empirical validation specified through a controlled before-and-after case-study protocol. Full article

The influence of hydrogenation, mechanical milling, and dehydrogenation parameters on the structure and properties of titanium powders produced from titanium sponge via the hydride–dehydride (HDH) process was investigated. The aim of the study was to compare representative HDH processing routes and identify the processing route that provided the most favorable structural characteristics for subsequent mechanical alloying and powder metallurgy applications. Commercially pure Grade 0 titanium sponge was used as the starting material and was subjected to hydrogenation at temperatures ranging from 350 to 650 °C, short-duration mechanical milling in an argon atmosphere, and vacuum dehydrogenation at temperatures between 750 and 950 °C. The resulting powders were characterized using laser particle size analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). The results showed that increasing the hydrogenation temperature promoted the formation of the TiH₂ hydride phase and enhanced powder fragmentation during subsequent mechanical milling. XRD analysis demonstrated effective dehydrogenation, as evidenced by the disappearance of detectable TiH₂ reflections and the restoration of the α-titanium phase within the detection limits of the technique. Qualitative SEM observations indicated that the investigated HDH processing routes influenced particle morphology and agglomeration behavior, whereas EDS analysis demonstrated a relatively uniform distribution of the detected elements without revealing detectable contamination within the analyzed regions. Mechanical alloying of the selected powders with aluminum and vanadium showed that, among the investigated processing routes, the H2–M2–D2 condition provided the most favorable combination of particle size distribution, phase composition, morphology, and elemental distribution for the production of a mechanically alloyed Ti–Al–V powder mixture. Full article

The Texas tortoise (Gopherus berlandieri) has a small geographic range in the USA and faces threats from habitat loss and alteration. Despite being a Texas state threatened reptile, it is surprisingly understudied. We conducted extensive road cruising surveys focused on the eastern part of the Texas tortoise range, but only seven Texas tortoises were observed. Limitations to our study included inaccessible large private landholdings with potential tortoise habitat. Georeferenced tortoise locations, along with museum records, were compiled from online databases and used to model habitat suitability with Maxent. The model predicted relatively small patches of suitable habitat in the eastern region, while the largest extent of suitable habitat was detected in the western region and far south Texas, as well as some patches outside the historical range. This spatial analysis redirects conservation efforts toward highly suitable habitat patches at risk of fragmentation and alteration in Texas. Future monitoring will improve our understanding of ongoing and increasing disturbances in the region and aid in the protection of this imperiled species in the US. Full article

The ballistic performance of a non-commercial aramid/epoxy composite laminate subjected to Fragment Simulating Projectile (FSP) impact was investigated through combined experimental testing and numerical simulation. Ballistic tests were performed in accordance with STANAG 2920 to determine the ballistic limit velocity (V₅₀). Complete and partial penetration responses were identified, with the ballistic transition region occurring between 412 and 452 m/s. The experimental ballistic limit was V₅₀ = 440.57 m/s. A three-dimensional finite element model was developed in ANSYS^® AUTODYN 2026 R1 using a Lagrangian formulation and an orthotropic constitutive model incorporating elastic behavior, stress/strain-based failure criteria, post-failure response, and geometric strain erosion. The numerical simulations predicted a ballistic limit of V₅₀ = 440.65 m/s, corresponding to a relative difference of less than 0.03% with respect to the experimental result. The numerical model successfully reproduced the ballistic transition, damage evolution, projectile velocity history, and energy transfer during impact, providing good agreement with the experimentally observed penetration responses. These results demonstrate that the proposed methodology provides a reliable and validated framework for predicting the ballistic response of aramid/epoxy composite laminates under standardized FSP impact conditions and supports the design and evaluation of lightweight composite armor systems. Full article

Agricultural productive services (APS) play an important role in improving agricultural efficiency and ensuring food security. Existing studies have widely recognized that labor scarcity induced by rural labor transfer stimulates farmers’ demand for APS and promotes the expansion of agricultural service markets. Yet non-farm employment in developing countries is often characterized by instability, temporariness, and informality, which may generate volatile service demand and undermine the sustainable provision of APS. Based on survey data from 684 maize-producing households in China, this study constructs a multidimensional index of non-farm employment quality and investigates how it influences APS adoption intensity and transaction stability. Our results confirm that improvements in non-farm employment quality significantly increase APS adoption intensity, and the findings remain stable under alternative measurements and estimation methods. Mechanism analysis reveals that higher employment quality promotes APS adoption intensity by reducing farmers’ risk perception, while this effect is moderated by social capital. Heterogeneity analysis shows that the positive effect of non-farm employment quality is concentrated among growth-stage households, lower-land-fragmentation households, small-scale households, and single-type employment households. Further analysis indicates that higher employment quality contributes to more stable and long-term contractual relationships between farmers and service providers. By highlighting the importance of non-farm employment quality in stabilizing agricultural service demand and fostering stable transaction relationships, this study contributes to ongoing discussions on rural labor transformation and the sustainable development of APS markets under smallholder farming systems in developing countries. Full article

A novel spiro[indoline-3,2′-thiazolidine]-2,4′-dione derivative incorporating 3-chloro-4-fluorophenyl and 6-methoxypyridin-3-yl fragments was synthesized and characterized. The synthetic route involved a two-step procedure, including the preparation of the spirocyclic scaffold via cyclocondensation of 5-fluoroisatin with 3-chloro-4-fluoroaniline in the presence of mercaptoacetic acid, followed by Knoevenagel condensation with 6-methoxypyridine-3-carbaldehyde. The reactions were carried out under reflux conditions and afforded the desired product in a satisfactory yield after purification by recrystallization. The structure of the synthesized compound was confirmed by ¹H and ¹³C NMR spectroscopy, LC–MS analysis, FT-IR and elemental analysis, all of which were consistent with the proposed molecular structure. The presence of multiple pharmacologically relevant heterocyclic motifs within a single framework suggests that this compound may serve as a useful scaffold for further biological evaluation. Full article

Background/Objectives: Clariid catfishes are a cornerstone of Southeast Asian aquaculture, where intensive breeding and interspecific hybridization have significantly decreased genetic diversity. To address the limited understanding of growth-governing molecular determinants, we characterized the genomic architecture and evolutionary dynamics of the myogenic factor 5 (Myf5) gene, a master regulator of myogenesis, in 511 individuals from 17 catfish populations in Thailand. Methods: A total of 511 individuals representing 17 catfish populations were analyzed. A 334-bp fragment of exon 1 of the Myf5 gene was sequenced using Illumina short-read technology. Genetic diversity indices were calculated to evaluate sequence variation, population structure, and selective constraints acting on the locus. Results: Sequence analysis of a 334-bp segment of exon 1 using Illumina short-read technology identified 17 haplotypes and 92 variable sites, which revealed moderate allelic richness despite low overall nucleotide diversity (π ≈ 0.008). Evolutionary analyses indicated that the Myf5 locus is governed by stringent purifying selection (ω = 0.063), wherein site-specific constraints preserve the stability of the α-helix folding architecture, which is essential for myogenic regulation. Population genetic analyses revealed substantial differentiation among taxa (56% among-population variation), while Bayesian clustering successfully resolved a hierarchical structure (K = 2) that distinguished Clarias gariepinus, Clarias macrocephalus, and Clarias batrachus. These findings demonstrate that species-specific Myf5 haplotypes serve as diagnostic markers for identifying parental species and assisting in the identification of F₁ hybrid stocks. Conclusions: Overall, this study provides the molecular markers for species identification, broodstock authentication, hybrid detection, and sustainable genetic management of Thai Clariid resources, which are critical for balancing production efficiency with the conservation of native biodiversity in Southeast Asia. Full article

Capillary electrophoresis (CE) is widely used for DNA fragment analysis, but its separation performance depends strongly on the composition of the polymer sieving matrix, especially in multicapillary systems where matrix operability and reproducibility are critical. Herein, a laboratory-built multicapillary electrophoresis system was used to optimize the sieving matrix for high-throughput DNA fragment separation. The system integrated twelve fused-silica capillaries, high-voltage electrokinetic injection, fluorescence detection, and digital electropherogram acquisition. Using a 100 bp DNA ladder as the model sample, the effects of poly(ethylene oxide) (PEO), Tween 20, and glycerol on electropherogram quality were systematically investigated. PEO concentration was the dominant factor controlling the dynamic sieving network: 0.1% PEO provided insufficient separation, whereas 0.8–1.0% PEO produced clearly resolved DNA peaks. Tween 20 improved peak regularity and electropherogram quality under the tested conditions, with 0.05% providing sufficient improvement without prolonging migration time. Glycerol affected peak distribution by increasing apparent migration resistance in the polymer matrix; however, excessive glycerol slowed DNA migration and markedly extended the separation window. Considering separation quality, matrix operability, and analytical efficiency, 1.0% PEO, 0.05% Tween 20, 2.5% glycerol, 1× SYBR Gold, and 0.5× TBE were selected as the optimized sieving matrix. Under the optimized matrix, inter-capillary migration-time alignment improved the consistency of parallel capillary outputs, with corrected migration-time RSD values generally below 0.5%. The optimized formulation provides a practical basis for high-throughput CE-based DNA fragment analysis. Full article

Plant mitochondrial genomes are important for respiration, organelle evolution, and phylogenetic inference, yet remain poorly characterized in Clausena lansium, an economically important Rutaceae fruit tree. Here, we generated the complete mitogenome of C. lansium cultivar ‘Ji Xin’ by integrating Oxford Nanopore and Illumina sequencing data, followed by comparative analyses of repeats, plastid-derived mitochondrial sequences, collinearity, RNA editing, and phylogenetic placement. The mitogenome consisted of two circular molecules totaling 499,621 bp, and encoded 56 genes, including 33 protein-coding genes, 20 tRNA genes, and three rRNA genes. Repeat analysis identified 206 SSRs, 21 tandem repeats, and 35 dispersed repeats, with dispersed repeats strongly enriched on mtChr1. We detected 21 plastid-derived mitochondrial fragments totaling approximately 9.23 kb, indicating limited but detectable plastid-to-mitochondrion DNA transfer. Comparative analyses revealed fragmented synteny between C. lansium and related Sapindales mitogenomes, suggesting lineage-specific structural rearrangement. Based on leaf rRNA-depleted lncRNA sequencing data, 402 candidate C-to-U RNA editing sites were detected in 31 mitochondrial PCGs, most of which were nonsynonymous. Phylogenetic reconstruction placed C. lansium within Rutaceae, close to Limonia and Citrus. These results provide a mitochondrial genomic resource for C. lansium and contribute to understanding mitogenome evolution in Rutaceae. Full article

As a vital component of cultural heritage, historic buildings carry multiple values, including historical continuity, construction techniques, and social memory. Their conservation and utilization are of significant importance for cultural transmission and economic development. However, existing research findings have long been dispersed across different themes, disciplines, and linguistic contexts, lacking a systematic integration and interpretive framework that links the entire conservation–utilization process, thereby constraining a comprehensive understanding of the field. Against this background, following the PRISMA guidelines, this study retrieved and screened 474 core journal articles published between 2005 and 2025 from the CNKI and the WOSCC. Using bibliometric and visualization analysis methods, and employing tools including CiteSpace, VOSviewer, Pajek, and Scimago Graphica, we analyzed publication trends, collaboration networks, disciplinary distributions, and knowledge structures, and conducted thematic mapping and cross-database comparison in conjunction with the management cycle articulated in international heritage conservation theory. The results show that publication volume in this field has generally exhibited a growth trend, and the research evolution has roughly undergone four stages: basic problem focus, emergence of digital technologies, digital transformation, and data-intensified assessment and intelligent applications. The research network presents a multi-centric pattern characterized by “fragmented distribution with localized clustering.” Cross-database comparison reveals that CNKI and WOS share common concerns in conservation, utilization, technology empowerment, and governance issues, but differ in thematic emphasis and methodological pathways. Based on the international heritage management cycle, this study maps out a systematic framework of “value recognition–risk assessment–conservation intervention–adaptive reuse–sustainable governance,” revealing the similarities and differences between the WOS and CNKI databases in thematic presentation and knowledge production pathways, and further identifies key issues including the insufficient independence of value research, inadequate methodological integration, weak post-utilization feedback, and the lack of a closed governance loop, thereby proposing future research directions. This study may serve as a reference for systematically understanding the overall knowledge and practical development in the field of historic building conservation and utilization. Full article

Understanding the environmental fate of microplastics (MPs) in agricultural soils remains a major challenge, particularly under field conditions where soil structure and hydraulic processes jointly regulate particle transport and retention. This study investigated whether hydro-physical soil functioning can explain the distribution and accumulation of MPs in pistachio orchard soils from a semi-arid region of southeastern Türkiye. A total of 42 soil samples were analyzed for MP abundance, size distribution, and morphology, together with key hydro-physical properties including texture, porosity, bulk density, aggregate stability, organic matter content, and soil water retention characteristics. To identify the dominant controls on MP occurrence, explainable machine learning approaches combining Random Forest (RF), Gradient Boosting Decision Trees (GBDT), and SHAP (SHapley Additive exPlanations) analysis were employed. Microplastic abundance differed among management systems. Former landfill or construction sites represented the largest proportion of the total recorded microplastic abundance (40.9%), followed by conventionally managed (25.2%), manure-amended (24.5%), and sewage-sludge-amended orchards (9.4%). Median microplastic abundances were 1433, 667, 4633, and 633 particles kg⁻¹ soil, respectively. Fine-sized MPs constituted the dominant particle fraction and exhibited strong associations with pore-system characteristics, indicating that pore-size compatibility governs their retention and mobility within the soil matrix. Morphology-specific analyses further revealed contrasting relationships between soil hydro-physical properties and individual MP forms, suggesting distinct retention pathways for granules, films, fragments, and fibers. Explainable AI analysis identified organic matter, silt content, bulk density, and water retention characteristics as the most influential predictors of MP occurrence. Among the tested models, RF demonstrated superior predictive robustness and generalization capacity. The findings demonstrate that hydro-physical soil functioning plays a central role in determining microplastic fate in agricultural soils and highlight the value of interpretable machine learning frameworks for uncovering the mechanisms underlying contaminant retention and redistribution. Integrating soil structural indicators with explainable artificial intelligence offers a promising pathway for improving microplastic risk assessment in agroecosystems. Full article

Gifted Education remains a contested and unevenly integrated domain within Initial Teacher Education (ITE). Its position is further complicated by conceptual instability surrounding identification, classification, and educational equity. Despite substantial contributions across psychology, neuroscience, and education, its translation into practice is constrained by conceptual instability, fragmented disciplinary accounts, and institutional pressures toward standardisation. This paper argues that the marginalisation of diverse Highly Able learners is not primarily due to insufficient knowledge, but to a structural failure to integrate existing knowledge into a coherent account of challenge. Drawing on policy analysis and interdisciplinary synthesis, the paper shows how psychological accounts of motivation and engagement, neuroscientific evidence on experience-dependent plasticity, and educational frameworks prioritising scalable pedagogy operate in parallel rather than in synthesis. Within ITE, this fragmentation contributes to a diminished understanding of high-level challenges; currently the challenge is often reduced to a simple notion of ‘stretch’ embedded within generic differentiation or adaptive teaching. To address this, the paper elaborates on Equality of Challenge as a normative and integrative principle, with a focus on low-threshold high-ceiling approaches. It reframes challenge as a matter of distributive justice and educational entitlement, positioning appropriately demanding educational experiences as a core entitlement for all learners rather than a targeted provision. It connects disciplinary insights into a shared account of how challenge should be designed and enacted within ITE and classroom practice. Full article

Background: Provincial pooling of the Urban–Rural Resident Basic Medical Insurance (URRBMI) fund has been promoted in China to reduce fragmentation and improve system performance, yet its impact on the efficiency of medical resource allocation remains unclear. Objective: To evaluate the impact of provincial pooling on medical resource allocation efficiency and to examine its heterogeneity across regions and institutional arrangements. Methods: Using provincial panel data from 2010 to 2022, this study measures efficiency with a super-efficiency slack-based measure (SBM) model and applies a staggered difference-in-differences (DID) design to estimate policy effects. Results: Provincial pooling is associated with a statistically significant reduction in medical resource allocation efficiency among adopting provinces. In baseline specifications, the estimated effect ranges from −0.021 to −0.024 (p < 0.01), corresponding to a decline of 0.021–0.024 points in the efficiency score, equivalent to about 2.4–2.7% of the sample mean efficiency level. Heterogeneity analysis suggests that the negative effect is concentrated in western provinces, whereas no statistically significant effect is observed in eastern provinces. No treatment effect is estimated for central provinces because none implemented provincial pooling during the study period. Institutional heterogeneity analysis shows negative estimates across pooling and management models, but the revenue–expenditure pooling estimate is not statistically significant. These results are robust across alternative specifications and sensitivity analyses. Conclusions: These findings suggest that, among adopting provinces, provincial pooling may involve substantial transitional adjustment costs, implying that efficiency gains should not be expected automatically in the short to medium term. Instead, outcomes depend on institutional conditions and the alignment of complementary governance mechanisms. Policymakers should adopt regionally differentiated and phased strategies and strengthen incentive-compatible design to improve reform effectiveness. Full article

Soil erosion on sloping cropland is a major threat to agricultural sustainability and ecological security in mountainous regions, yet its spatial distribution and landscape-level structural characteristics remain insufficiently quantified. Taking Zhaotong in northeastern Yunnan, China, as a typical mountainous agricultural region in the upper Yangtze River Basin, this study integrated Sentinel-2 imagery, high-resolution reference data, field survey information, the Google Earth Engine platform, a random forest classifier, the Chinese Soil Loss Equation, and landscape pattern metrics to assess soil erosion on sloping cropland. The land use classification achieved an overall accuracy of 90.70% and a Kappa coefficient of 0.88, providing a reliable basis for sloping cropland extraction. Sloping cropland covered 4218.77 km², accounting for 84.64% of total cropland area, but contributed 1.84 × 10⁷ t·yr⁻¹ of annual soil loss, equivalent to 97.51% of total cropland erosion. The mean erosion rate of sloping cropland reached 4260.50 t·km⁻²·yr⁻¹, and 95.84% of sloping cropland exceeded the soil loss tolerance threshold. County-level analysis revealed strong spatial heterogeneity, with high erosion risks concentrated in northern and eastern mountainous counties. Intensive, Severe, and Extreme erosion occupied only 26.14% of the sloping cropland area but contributed 62.21% of total soil loss. Landscape metrics further showed that Moderate erosion had the highest patch density and edge density, indicating a critical fragmentation stage in erosion development. These findings support a tiered conservation strategy in which high-intensity patches are prioritized for immediate sediment reduction, while fragmented Moderate-erosion (2500–5000 t·km⁻²·yr⁻¹) areas receive preventive management. The proposed framework provides a useful approach for identifying erosion hotspots and supporting targeted soil and water conservation in mountainous agricultural landscapes. Full article