Search Results (6,251)

In the operation mode arrangement of bulk power systems, unreasonable reactive power injection data at nodes tend to result in power flow calculation non-convergence. Owing to the extremely high dimension of the variable space and the heterogeneous impacts of different variables on power flow convergence, it is imperative to accurately identify the key variables inducing non-convergence and provide physical justifications. For this purpose, this paper proposes a data-driven key variable identification and adjustment method: firstly, based on the blocking cut-set theory and the characteristic that the active unbalanced power ΔP of intermediate power flow exhibits opposite signs at the sending and receiving ends of the cut-set, a blocking cut-set identification method leveraging the characteristics of the active unbalanced power of intermediate power flow is developed; secondly, relying on the feature that the reactive unbalanced power ΔQ of intermediate power flow is less than zero, a key variable identification method based on the characteristics of the reactive unbalanced power of intermediate power flow is presented; finally, a key variable adjustment method grounded in the numerical value of ΔQ is proposed. The validity of the proposed approach was validated via simulated computations using both the IEEE 39 bus system and a practical bulk power system. Full article

Background: Intraoral radiography remains highly operator-dependent, with small deviations in beam angulation or receptor placement leading to geometric distortions, diagnostic inaccuracies, and repeated exposures. This pilot study introduces and evaluates a gyroscopic-guided, laser-assisted radiographic device designed to standardize cone positioning and improve the geometric reliability of bisecting-angle intraoral radiographs. Methods: Eighteen dental graduates and practitioners performed periapical radiographs on phantom models using a charge-coupled device (CCD) sensor over six months. Each participant obtained six standardized projections with and without the device, yielding 200 analysable radiographs. Radiographic linear measurements included tooth height (occluso–apical dimension) and tooth width (mesio-distal diameter), which were compared with reference values obtained using the paralleling technique. Radiographic errors—including cone cut, elongation, proximal overlap, sliding occlusal plane deviation, and apical cut—were recorded and compared between groups. Results: Use of the gyroscopic-guided device significantly enhanced geometric accuracy. Height measurements showed a strong correlation with reference values in the device group (r = 0.942; R² = 0.887) compared with the non-device technique (r = 0.767; R² = 0.589; p < 0.0001). Width measurements demonstrated similar improvement (device: r = 0.878; R² = 0.770; non-device: r = 0.748; R² = 0.560; p < 0.0001). Overall, the device reduced technical radiographic errors by approximately 62.5%, with significant reductions in cone cut, elongation, proximal overlap, sliding occlusal plane errors, and tooth-centering deviations. Conclusions: Integrating gyroscopic stabilization with laser trajectory guidance substantially improves the geometric fidelity, reproducibility, and diagnostic quality of intraoral radiographs. By minimizing operator-dependent variability, this innovation has the potential to reduce repeat exposures and enhance clinical diagnostics. Further clinical trials are recommended to validate performance in patient-based settings. Full article

Sustainable diet transitions are required to protect human and planetary health, and consumers are important food systems actors who can foster positive changes. However, little is known about how consumers perceive the concept of sustainable diets. This study explored perceptions of sustainable diets across five high- and middle-income countries: Japan, Indonesia, Italy, Canada, and Mexico. Semi-structured interviews were conducted with 184 young adults (30–45 per country), and transcripts were analyzed using values coding to understand the values, attitudes, and beliefs that shape behaviours related to sustainable diets. Results revealed that defining “sustainable eating” was challenging for participants across all countries. While participants’ values regarding sustainable diets were often context-specific with marked differences across countries, common themes across countries included concern about food waste and packaging and the belief that sustainability should be the responsibility of all actors across the food system, not just the individual. These findings indicate that food policy should address both individual and systemic dimensions of food sustainability, specifically prioritizing strategies for waste and packaging infrastructure. Furthermore, public health strategies must be values-oriented and culturally tailored to ensure they resonate with local consumer priorities. Full article

The news framing of assisted death in Portugal and the United Kingdom from 2016 to 2024 was analyzed across two dimensions. The first examined the overall frames through source positions and occupations. The second observed argumentative structures by coding argument characteristics: manifestation, origin, level, and evaluation. A total of 7464 structures were identified from 1731 published stories in Expresso, Público, The Guardian, and The Telegraph. The research utilized a methodological framework based on framing theory, creating direct connections between frame analysis and argumentative structures to improve the validity of valence and thematic framing mechanisms. The findings indicated significant differences between countries. The Portuguese news media showed a marked inclination to present concentrated opposing arguments with a higher argumentative density. In contrast, British newspapers displayed a greater diversity of arguments in favor of assisted death, along with a more cohesive representation among pro-assisted death sources. Three distinct argumentative profiles were identified, each showing different divisions between Portugal and the UK. These results reveal that argumentative structures in assisted death coverage reflect deeper systemic values and news media structures, positioning these quality newspapers as influential actors in representing arguments about moral legitimacy around bioethical issues. The study makes a valuable contribution by offering a comprehensive understanding of how these four newspapers frame arguments about assisted death while proposing an innovative analytical model applicable to comparative studies of other news media. Full article

This classroom-based case study examines how an AI-mediated Socratic dialogue, implemented through ChatGPT, can support students’ engagement and perceived learning in undergraduate thermodynamics. Conducted in a first-year engineering physics course at a private university in northern Mexico, the activity invited small student groups to interact with structured prompts designed to promote inquiry, collaboration, and reflective reasoning about the adiabatic process. Rather than functioning as a source of answers, ChatGPT was intentionally positioned as a mediating scaffold for Socratic questioning, prompting students to articulate, examine, and refine their reasoning. A mixed-methods approach was employed, combining a 10-item Likert-scale survey with construct-level statistical analysis of two focal dimensions: perception of learning and engagement, including an exploratory comparison by gender. Results indicated consistently high levels of perceived learning and engagement across the cohort, with average scores above 4.5 out of 5. At the construct level, no statistically significant gender differences were observed, although a single item revealed higher perceived learning among female students. Overall, the findings suggest that the educational value of ChatGPT in this context emerged from its integration within a Socratic, inquiry-oriented pedagogical design, rather than from the technology alone. These results contribute to ongoing discussions on the responsible and pedagogically grounded integration of generative AI in physics education and align with Sustainable Development Goal 4 (Quality Education). Full article

Background: Sleep is a key determinant of recovery and performance in elite athletes, yet its optimization extends beyond sleep duration alone and encompasses multiple subjective and physiological dimensions. Environmental factors, including the sleep surface, represent modifiable components of sleep that may influence perceived sleep quality. This study aimed to examine whether an individually adjustable modular sleep system improves subjective sleep quality in elite athletes and whether alterations in objective sleep metrics, circadian timing, or nocturnal autonomic physiology accompany such changes. Methods: Forty-three elite athletes participated in this pre–post-intervention study (without a control group). Subjective sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), while objective sleep and physiological parameters were recorded using a wearable device (Oura Ring, 3rd generation). Outcomes were averaged across three consecutive nights at baseline (T0) and post-intervention (T1). Baseline values were derived from the final three nights of a standardized pre-intervention monitoring period (minimum 7 nights), and post-intervention values from the final three nights following a standardized intervention exposure period (minimum 14 nights). Statistical analyses included paired frequentist tests and complementary Bayesian paired-sample analyses. Results: Subjective sleep quality improved significantly following the intervention, with a mean reduction in PSQI score of 0.67 points (p < 0.001). In contrast, no meaningful changes were observed in total sleep time (p = 0.28), REM duration (p = 0.26), circadian timing (p = 0.47), or nocturnal minimum heart rate (p = 0.42), as supported by the absence of physiological changes in these parameters. Conclusions: It seems that an individually adjustable sleep system can be able to improve perceived sleep quality in elite athletes without disrupting sleep architecture, circadian regulation, or nocturnal autonomic function. In athletes whose sleep duration and physiological sleep metrics are already near optimal, such micro-environmental interventions may offer a feasible, low-risk means of enhancing recovery by targeting subjective sleep quality. This dimension dissociates from objective sleep measures. Optimizing the sleep surface may therefore represent a practical adjunct to existing recovery strategies in high-performance sport. Full article

Rural governance is a key means of promoting sustainable rural development and is gradually evolving toward interdisciplinary research across multiple scales. How should governments at all levels implement precise policy to achieve rural revitalization goals? To reveal the multi-scale characteristics of rural spatial governance, this study proposes theoretical hypotheses and constructs a three-level analytical framework encompassing the municipal, functional area, and township dimensions. Taking Nanning City as a case study, it comprehensively employs global and local spatial autocorrelation methods to quantitatively analyze the spatial differentiation patterns and governance effectiveness across the five dimensions of rural revitalization at different scales. The results indicate that indicators such as ecological livability, industrial prosperity, life affluence, rural civilization, and effective governance all exhibit significant clustering patterns at various scales, with notable differences in the intensity of clustering across these scales. Specifically, the ecological livability indicator exhibits the strongest spatial agglomeration at the municipal level (Moran’s I = 0.578), industrial prosperity and affluent living show the strongest correlations at the functional area level (with average Moran’s I values of 0.281 and 0.414, respectively), while rural civilization and effective governance display the most pronounced clustering at the township level (Moran’s I values of 0.363 and 0.350). The findings provide direct evidence for implementing differentiated and precise rural spatial governance in Nanning City and similar regions, while also contributing to the optimization of cross-level policy resource allocation. Future research should further integrate multidisciplinary perspectives and expand the analysis of multi-stakeholder participation mechanisms. Full article

Empathic behavior is increasingly incorporated into socially assistive robots, yet little is known about how older adults’ personality-based self-regulatory processes shape responses to such designs. The present study examined a recognition-based “mirror effect” framework of narcissistic self-regulation, referring to the ways individuals maintain a valued self-image through social feedback and acknowledgment. We focused on two core dimensions: narcissistic admiration, characterized by self-promotion and the pursuit of affirmation, and narcissistic rivalry, characterized by defensiveness, antagonism, and sensitivity to threat. Community-dwelling older adults (N = 527; M_age = 72.73) were randomly assigned to view a video of a socially assistive robot interacting in either an empathic or a cold manner. Participants reported their perceived recognition by the robot, defined as the subjective experience of feeling seen, acknowledged, and valued, as well as multiple robot evaluations (anthropomorphism, likability, perceived intelligence, safety, and intention to use). At the mean level, empathic robot behavior increased perceived recognition, anthropomorphism, and likability but did not improve perceived intelligence, safety, or intention to use. Conditional process analyses revealed that narcissistic admiration was positively associated with perceived recognition, which in turn predicted more favorable robot evaluations, regardless of robot behavior. In contrast, narcissistic rivalry showed a behavior-dependent pattern: rivalry was associated with reduced perceived recognition and less favorable evaluations primarily in the empathic condition, whereas this association reversed in the cold condition. Importantly, once perceived recognition and narcissistic traits were accounted for, the cold robot was evaluated as more intelligent, safer, and more desirable to use than the empathic robot. Studying these processes in older adults is theoretically and practically significant, as later life is marked by shifts in social roles, autonomy concerns, and sensitivity to interpersonal evaluation, which may alter how empathic technologies are experienced. Together, the findings identify perceived recognition as a central psychological mechanism linking personality and robot design and suggest that greater robotic empathy is not universally beneficial, particularly for users high in rivalry-related threat sensitivity. Full article

The optimization of historic district form, given the coordinated relationship between global urbanization and sustainable development, faces the core contradiction between preservation and development. Taking Shenyang’s Nanshi area as a case study, this study aimed to construct a sustainable urban form evaluation system comprising 7 dimensions and 23 indicators by integrating multi-source geographic Big Data. A combination of a weighting approach in rank-order analysis and the entropy weight method was adopted, followed by spatial quantitative analysis conducted based on ArcGIS. The results showed that the sustainability of the area exhibited significant spatial differentiation: historic blocks became high-value areas due to their “small blocks, dense road network” fabric and high functional mix. However, newly built residential areas were low-value zones, constrained by factors such as fragmented green spaces, single-functional land use, and other limitations. Road network density and functional mixing were identified as the primary driving factors, while green coverage rate served as a secondary factor. Based on these findings, a three-tier “element–structure–system” optimization strategy was proposed, providing quantitative decision support for the low-carbon renewal of high-density historic urban districts. Full article

This paper analyses the role of landscape as a fundamental dimension of post-earthquake recovery in the inland areas of Central Italy, arguing that reconstruction must be understood not only as the repair of damaged buildings but as a broader territorial process affecting identity, spatial organization, and long-term settlement trajectories. In this sense, post-earthquake recovery is also interpreted as a strategic opportunity to reinforce coast–inland relationships, acknowledging the structural interdependence between inland Apennine areas and coastal urban systems. Drawing on insights from applied research conducted in the L’Aquila 2009 crater and on the conceptual framework developed within the PRIN TRIALS project, the paper discusses how seismic events accelerate pre-existing territorial dynamics and produce enduring transformations, particularly in the proximity landscapes surrounding historic centres. Rather than presenting empirical findings, the contribution offers a theoretical and operational framework aimed at integrating landscape considerations into reconstruction processes. It outlines key concepts such as landscape quality, transformative resilience, and permanent temporariness; reviews critical normative aspects linked to emergency procedures; and proposes a set of landscape-oriented guidelines and criteria for the contextual integration of reconstruction projects. These include landscape quality objectives, multiscalar readings of identity values, and operational tools such as visual-impact assessment, Project Reference Context analysis, and principles for managing transformations in peri-urban and historic environments. Overall, the paper argues that adopting a landscape-based perspective can strengthen territorial cohesion, support the sustainable redevelopment of historic centres and their surroundings, and embed post-earthquake reconstruction within broader coast–inland territorial strategies aimed at long-term resilience and balanced regional development in Apennine communities. Full article

Unique fractal characteristics are significantly controlled by shale lithofacies, mineralogical characteristics, and OM features, which in turn determine reservoir properties and gas-bearing capacity. However, a comprehensive understanding of fractal features has remained insufficient. This study presents a systematic investigation into the full-scale pore size distribution for the Wufeng–Longmaxi shales in Sichuan Basin which employed low-pressure CO₂ adsorption (CO₂GA), N₂ adsorption (N₂GA), and mercury injection capillary pressure (MICP), as well as field emission scanning electron microscope (FE-SEM) techniques. The fractal dimensions of pores across different pressure ranges were revealed by different fractal models. The results demonstrate that the shale pores are dominated by micro- to mesopores and partial extremely larger pores, contributed primarily by organic matter (OM) pores and microcracks, respectively. Fractal dimensions follow a consistent increasing order: D_C < D_N1 < D_N2 < D_M or D_C < D_N1 < D_M < D_N2, suggesting that larger pores with diameters lager than 5 nm are more heterogeneous and complex compared to the pores less than 5 nm (smaller pores). This is because smaller pores are predominantly composed of OM pores, while larger pores comprise a mixture of OM pores, mineral-related pores, and microcracks. Different fractal dimensions, in turn, are influenced by distinct factors. The D_C value exhibits a positive correlation with micropore volume. D_N1 and D_N2 values are positively correlated with the content of brittle minerals and TOC, while they show negative correlations with the content of clay minerals. Notably, D_M values do not demonstrate a significant correlation with shale compositions, primarily owing to the development of microcracks. Fractal dimensions, particularly D_N1 and D_N2, are significantly controlled by the lithofacies of shale. The highest D_N1 and D_N2 values occur in the siliceous shale lithofacies, and the mixed shale lithofacies exhibit moderate D_N1 and D_N2 values, whereas the lowest D_N1 and D_N2 values primarily occur in clay-rich shale lithofacies. Different fractal dimensions show various correlations with shale gas content. The Langmuir volume as well as total gas content exhibit significant correlations with D_N1 and D_N2 values, while they exhibit no obvious correlations with D_C and D_M values. This implies that pores with diameters of 1.8–55 nm serve as primary storage sites for both adsorbed and free gas. The findings can significantly improve the cognition of adsorbed gas and free gas behavior in shale reservoirs. Full article

Grasslands represent an essential resource for rural economies and for the provision of ecosystem services, yet they are increasingly affected by anthropogenic pressures, functional land-use changes, and institutional constraints. This study develops a geospatial decision-support framework for assessing grassland suitability in Hunedoara County, Romania, by integrating the Analytic Hierarchy Process (AHP) and Weighted Overlay Analysis (WOA) within a GIS environment. The assessment is based on nine criteria thematically grouped into three dimensions: (A) physical-geographical, including topographic suitability, climatic pressure, and hydrological risk exposure; (B) ecological and conservation-related, reflected by ecological conservation value, ecological carrying capacity, and the anthropic pressure index; and (C) socio-economic and functional, represented by spatial accessibility, recreational value, and policy support mechanisms. Suitability is defined as the integrated capacity of grasslands to sustain productive and multifunctional uses compatible with ecological conservation and the existing policy framework. Results indicate that 0.43% of the grassland area exhibits very high suitability (Class 1), 44.51% high suitability (Class 2), and 54.75% moderate suitability (Class 3), while unfavorable areas account for only 0.31% of the total (Class 4). The proposed methodology is reproducible and transferable, providing support for prioritizing management interventions, agri-environmental payments, and rural planning in mountainous and hilly regions. Full article

Entrepreneurship aims to contribute significantly to economic development, a trend that has been progressively growing over time. Nonetheless, female entrepreneurs continue to face substantial challenges, including limited access to financial resources and sociocultural barriers. The influence of Entrepreneurial Coaching (EC) offers a valuable perspective for analysing entrepreneurial self-efficacy and business growth. Grounded in Systems Theory, the research examines how EC interventions can bolster the confidence of women entrepreneurs and facilitate adaptive responses to business challenges. Utilising a quantitative, explanatory research design, the study employed convenience and snowball sampling to recruit 257 women entrepreneurs who received coaching. The relationships among EC, the six dimensions of entrepreneurial self-efficacy (ESE), and business growth outcomes were analysed utilising Structural Equation Modelling (SEM). Although seven hypotheses were proposed, only four were supported, whereas three were refuted. The findings show a positive correlation between EC and business growth. The supported hypothesis concerning coping with unexpected challenges, investor relations, and core purpose (value proposition) was accepted. Conversely, hypotheses regarding new product and market development, innovative environments, and the development of critical human resources were not supported. This research extends the existing literature on Entrepreneurial Coaching by demonstrating that the capacity to navigate unforeseen challenges, manage investor relations, and adhere to core purposes is correlated with business growth among women entrepreneurs. Thus, the significance of the study lies in the integration of Entrepreneurial Coaching, Entrepreneurial Self-Efficacy, and Business Growth. Full article

This study systematically verified the applicability and accuracy of the Probability Density Evolution Method (PDEM) in the probabilistic modeling of the dynamic response of anchored rock slopes under random seismic action through large-scale shaking table model tests. Across 144 sets of non-stationary random ground motions and 7 sets of white noise excitations, key response data such as acceleration, displacement, and changes in anchor axial force were collected. The PDEM was used to model the instantaneous probability density function (PDF) and cumulative distribution function (CDF), which were then compared with the results of normal distribution, Gumbel distribution, and direct sample statistics from multiple dimensions. The results show that the PDEM does not require a preset distribution form and can accurately reproduce the non-Gaussian, multi-modal, and time evolution characteristics of the response; in the reliability assessment of peak responses, its prediction deviation is much smaller than that of traditional parametric models; the three-dimensional probability density evolution cloud map further reveals the law governing the entire process of the response PDF from “narrow and high” in the early stage of the earthquake, “wide and flat” in the main shock stage, to “re-convergence” after the earthquake. The study confirms that the PDEM has significant advantages and engineering application value in the analysis of random seismic responses and the dynamic reliability assessment of anchored slopes. Full article

Aleppo oak (Quercus infectoria) is among the most industrially and ecologically significant oak species, valued for its medicinal properties and considerable genetic importance. Cytogenetic analysis provides critical insight into evolutionary history, interspecific relationships, and karyotypic differentiation. This study investigated the chromosomal architecture and karyotypic diversity of five natural populations of this species in western Iran (Sardasht, Oramanat, Baneh, Paveh, and Marivan) using actively dividing root meristems and a high-resolution image-based cytogenetic system. All examined cells displayed a basic chromosome number of x = 12 and a diploid condition, and chromosome lengths ranged from 0.90 to 2.12 µm. ANOVA and mean comparisons of five chromosomal parameters (Long Arm, Short Arm and Total Length, Arm Ratio, and Centromeric Index) revealed significant interpopulation differences in chromosome length and arm dimensions. All populations shared the karyotype formula 12 m and were classified into Stebbins’ Category B, indicating a moderately symmetrical, relatively primitive cytogenetic structure. Principal component analysis reduced the dataset to two major axes explaining 99.93% of the total variance, predominantly influenced by SA and TL on PC1 and by LA, AR, and CI on PC2. Hierarchical clustering grouped the populations into three distinct lineages, with Sardasht–Oramanat–Baneh showing the greatest divergence. Biplot vector patterns further clarified trait correlations, highlighting genomic structuring and potential breeding utility. Full article