Search Results (2,360)

The diversity of forest tree life strategies is fundamental to species coexistence in mixed stands. Growth rate is one of the most important elements of a species’ life strategy. This aspect has been relatively well recognised in even-aged stands. However, the situation is different in uneven-aged stands, particularly in multi-species stands comprising species with different light demands. In this study, we aimed to compare stem basal area increment (BAI) in regard to five species forming multi-species, uneven-aged deciduous forests in Central Europe as an important element of their growth strategy. Particular attention was paid to the relationship between this feature and tree height and competitive status. These relationships were analysed using a linear mixed model. The BAI was positively correlated with tree height, while a negative correlation was observed between BAI and increasing competitive level. However, the observed variations in the trends of these relationships were not associated with the light demands of the compared species. In general, the majority of the studied species demonstrated similar growth dynamics. This may suggest that the role of this trait in shaping species coexistence is modulated by other life-history strategy components and by specific growth conditions. An exception to this is the most light-demanding species, black alder (Alnus glutinosa (L.) Gaertner), which, contrary to expectations, exhibits a lower basal area increment under uneven-aged conditions. Full article

Advancing toward sustainable higher education requires simultaneously addressing United Nations Sustainability Goals 4 (quality education) and 5 (gender equality). This mixed-methods case study analyzes how cultural stereotypes and gender expectations influence career choices in the field of computer science, which is highly masculinized in Chile. As a contextual and comparative contrast, the feminization of disciplines such as nursing is considered, illustrating the gender polarization across areas of knowledge. This comparison is not random, since in Chile the health sector stands at the opposite end of the spectrum from technology, as demonstrated by the study’s figures. As a theoretical basis, a simple systematic review of the literature published between 2013 and 2024 (in English and Spanish) was carried out, drawing on Scopus, Web of Science, SciELO, and ERIC databases, following some steps of the PRISMA protocol. Thematic analysis allowed mapping research by region, discipline, and type of intervention. The results confirm the persistence of stereotyped beliefs about skills and professional roles, even in contexts with formal equity policies. Strategies that foster empathy, belonging, and intercultural communication, implemented through mentoring, outreach activities, or curriculum redesign, emerge as key catalysts for more inclusive environments. The study presents a practical case applied to first-year computer engineering students at the Universidad de La Frontera (Chile), in which gendered perceptions embedded in vocational choice processes were identified. By situating this study in Chile’s context, we identify how local structures—school sector, regional labor markets, and gender norms—shape women’s participation in computing. Based on this experience, practical recommendations are proposed for integrating a gender perspective into technology education, including pedagogical strategies, gender-sensitive vocational guidance, and the visibility of role models. Full article

Effective control of the rosy apple aphid, Dysaphis plantaginea, is crucial for maintaining apple orchard productivity. Understanding plant-mediated bottom-up and parasitoid-driven top-down interactions is critical for developing optimized pest management strategies. We investigated how host plant diversity and interactions between two parasitoids, Aphidius matricariae and Aphidius ervi, shape aphid suppression across seedlings from ten apple cultivars. Mummy counts, parasitism rate, emergence rate, and sex ratio measurements were used to assess the parasitoid preference and performance. Results revealed significant interactions between host plant identity and parasitoid performance. Mixed parasitoid releases outperformed single-species treatments. Alone, A. ervi achieved significantly higher parasitism rates than A. matricariae. Host plant effects were pronounced; Cripps Pink enhanced A. matricariae performance, while Golden Delicious and Red Delicious improved A. ervi metrics. Emergence rates and sex ratios varied by plant origins, with Elstar enhancing A. ervi and Granny Smith enhancing A. matricariae. Choice tests indicated cultivar-specific parasitoid preferences, and heatmap analysis revealed apparent competition among aphids mediated by parasitoids, with Braeburn and Gala acting as key parasitoid sources. Study findings indicate that managing apple cultivar diversity and exploiting complementary parasitoid interactions can improve D. plantaginea biocontrol in orchards. Full article

Digital twins are emerging as promising yet underexplored tools for addressing overtourism, sustainability, and governance challenges in tourism. This study assessed their acceptance using a mixed-methods design that combined a large-scale survey of tourists (N = 1286) with semi-structured stakeholder interviews across four Spanish destinations (Barcelona, Málaga, Valencia, and Benidorm). Factor analyses validated a six-dimensional acceptance model comprising trust, usefulness, ease of use, perceived risks, sustainability attitudes, and awareness. The quantitative results demonstrated that trust, usefulness, and ease of use strongly predicted adoption intentions, while risk perceptions negatively influenced acceptance. Sustainability orientations and digital familiarity further enhanced support. Qualitative insights revealed that governance capacity, equity concerns, and readiness critically shaped stakeholder evaluations, highlighting that adoption is mediated not only by individual perceptions but also by local infrastructural and institutional contexts. The study advances technology acceptance theory by integrating sustainability and awareness as domain-specific constructs and by showing how governance dynamics condition adoption across destinations. Practically, it underscores the need for institutional trust, transparent risk management, equitable participation, and alignment with sustainability agendas. While limited to Spanish destinations, the findings offer broader lessons for European cities seeking to embed digital twins in tourism governance. Full article

This study was driven by two primary objectives. The first objective focused on exploring the relationship between transformational and transactional leadership practices and teachers’ perceptions of their principals’ effectiveness. The second aimed to evaluate the adequacy of leadership training programs in Cyprus, with particular emphasis on how well these programs foster transformational leadership skills. To effectively address these goals, the research employed an explanatory sequential mixed methods design. For the quantitative phase, the Multifactor Leadership Questionnaire was administered to 630 teachers from 28 schools across all districts. Confirmatory Factor Analyses indicated that the Transformational and Transactional leadership dimensions could be represented by a higher-order factor. Subsequently, Structural Equation Modeling revealed a positive association between Transformational/Transactional leadership and principal effectiveness, whereas Passive-avoidant leadership showed a small negative association. For the qualitative phase, semi-structured interviews were conducted with five principals exhibiting different levels of adoption of transformational practices. Thematic analysis revealed shortcomings in current training programs, including a lack of substantive focus on preparing principals to become transformational school leaders. Overall, the study highlights the importance of transformational school leadership practices in shaping teachers’ perceptions of their principal effectiveness and emphasizes the need to revise principal training programs by incorporating transformational content. Full article

The overconsumption of plastic packaging has alarming repercussions on the environment, notably through waste accumulation in public spaces and clogged drains. This study identifies factors driving plastic proliferation, analyzes their impacts, and proposes strategies for sustainable waste management. A cross-sectional design combined document review, field observations, and interviews with 156 households and 24 informants. Descriptive statistics characterized consumption patterns and service access. Impacts were assessed through litter hotspots, blocked drains, flood-prone points, and reported health risks. Households used five to six plastic bags daily, while collection coverage remained below 50%, sustaining persistent leakage. Findings reveal excessive reliance on plastics, shaped by technical, social, and institutional gaps, including weak segregation and limited pre-collection. Agoè-Nyivé 4, a fast-growing peri-urban commune within Greater Lomé, faces limited services but high consumption, making it a relevant case for rapidly growing municipalities. Yet the population often adopts counterproductive practices, hampering responsible waste management. A policy mix is outlined: expanding pre-collection and door-to-door services, integrating informal collectors, and targeted community sensitization. Without urgent interventions, plastic leakage will intensify environmental degradation, flooding, and health risks. The study recommends integrated policy measures to curb single-use dependence and foster a local circular economy. Full article

Research on coastal recreational activities has grown substantially, yet studies focusing on user perceptions of these spaces—critical for optimizing tourism experiences and management—remain fragmented and underdeveloped. This study addresses this gap by examining tourist sentiment in Xiamen, a renowned coastal city in China, using social media data. Text mining tools were utilized to process the Weibo contents through text segmentation, frequency analysis and cluster analysis. The Two-way Neural Network Fusion Model Based on the BERT (TNNFMB) deep learning approach was employed using transfer learning for sentiment analysis, while the Latent Dirichlet Allocation (LDA) model was used to uncover latent thematic patterns. Sentiment polarity analysis revealed that positive comments constituted 56.47%, negative comments only 16.3%, and neutral comments 27.2%, confirming a generally positive perception of visitors’ coastal experiences. Tourists’ social media posts primarily revolve around five core themes in coastal areas: coastal waters, waterfronts, adjacent environments, culture and creativity, and reputation and expectation. The spatial and temporal changes in sentiment scores were discovered. Areas emphasizing sea–land landscapes, cultural theme reinforcement, and open public activities generally achieved high and stable sentiment scores. Natural and natural–artificial mixed coastlines experienced significant seasonal variations in sentiment. The recommendations of this study, generated from a sentiment perspective, include shaping a harmonious coastal environment by improving coastal management and support services to enhance the comfort of the tourist experience. This study advances understanding of user-centric coastal tourism dynamics, providing evidence-based tools for managers to enhance tourist experiences and spatial quality. Full article

The COVID-19 pandemic altered individuals’ worldviews. This study examined how cultural values shaped the ways students navigated stress and adapted after the COVID-19 pandemic. Drawing on Conservation of Resources (COR) Theory and cultural psychology frameworks of individualism and collectivism, we hypothesized that university students in two culturally distinct contexts—China and Canada—would demonstrate resilience differently. Chinese students would display collectivistic coping strategies (e.g., social responsibility and perspective-taking), while Canadian students would show resilience through individualistic strategies (e.g., personal reflection and self-efficacy). A total of 814 students completed a mixed-methods survey assessing resilience, cognitive reflection, and post-pandemic adaptations. Quantitative data were analyzed using factor analysis and stepwise regression to identify predictors. Qualitative responses were thematically analyzed for context. Results revealed cultural differences in resilience and adaptation, with social responsibility, healthy habits, and third-person perspective-taking predicting the responses of Chinese students, whereas internal emotional processing and personal moral reflection predicting it for Canadian students. This study enhances cross-cultural understanding of resilience and adaptation after collective trauma. Full article

Ship instance segmentation in remote sensing images is essential for maritime applications such as intelligent surveillance and port management. However, this task remains challenging due to dense target distributions, large variations in ship scales and shapes, and limited high-quality datasets. The existing YOLOv8 framework mainly relies on convolutional neural networks and CIoU loss, which are less effective in modeling global–local interactions and producing accurate mask boundaries. To address these issues, we propose CDSANet, a novel one-stage ship instance segmentation network. CDSANet integrates convolutional operations, Vision Transformers, and attention mechanisms within a unified architecture. The backbone adopts a Convolutional Vision Transformer Attention (CVTA) module to enhance both local feature extraction and global context perception. The neck employs dynamic-weighted DOWConv to adaptively handle multi-scale ship instances, while SIoU loss improves localization accuracy and orientation robustness. Additionally, CBAM enhances the network’s focus on salient regions, and a MixUp-based augmentation strategy is used to improve model generalization. Extensive experiments on the proposed VLRSSD dataset demonstrate that CDSANet achieves state-of-the-art performance with a mask AP (50–95) of 75.9%, surpassing the YOLOv8 baseline by 1.8%. Full article

Adjoint-based optimization methods, that were previously in the realm of computational fluid dynamics (CFD) research, are now available in commercial software. This work explores the use of adjoint-based optimization to maximize mixing and combustion efficiencies for a supersonic combustor. To this end, a two-dimensional combustor was considered with parallel hydrogen injection. Simulations were carried out based on the steady Reynolds-Averaged Navier–Stokes equations and optimization was performed using a simplified passive scalar field instead of the full reactive flow problem. The optimization of a triangle-shaped mixing element is considered in addition to a case allowing the entire bottom of the combustor to deform. The relatively small mixing element could not boost efficiency significantly. By comparison, the optimization of the combustor wall resulted in both mixing and combustion efficiency gains accompanied by total pressure loss penalty. The optimization achieved higher efficiency compared to the baseline by extending the total volume of the reaction zone. The presented proof-of-concept results are relevant for the design of hypersonic vehicle propulsion systems, such as scramjets. Full article

This paper assesses the correlates of perceived well-being among young women aged 18 to 30 in five Balkan cities: Athens, Greece; Plovdiv, Bulgaria; Bucharest, Romania; Nis, Serbia; and Shtip, North Macedonia, by integrating urban, travel behavioural, and socio-economic features. A cross-sectional survey was employed using standard questionnaires including the Warwick–Edinburgh Mental Well-being Scale (WEMWBS), the short version of the International Physical Activity Questionnaire (IPAQ), and the adapted ALPHA environmental questionnaire. To answer research questions, linear regression models were developed to analyse predictors of well-being at both regional and national levels. Results show that neighbourhood and mobility features play a significant role in shaping mental well-being. Access to walkable sidewalks, green spaces, mixed land-use structure, and attractive local facilities (e.g., shops, recreational centres in the neighbourhood) were consistently associated with higher levels of well-being. Conversely, perceived insecurity, especially at night or regarding bicycle theft, significantly reduced well-being. Physical activity levels, particularly days of walking and vigorous activity, showed strong positive associations, underscoring the role of active lifestyles in promoting mental health. Socio-economic variables, including financial status, relationship status, and work status, were also found to be linked to perceived well-being. Cycling-related variables may affect Greek well-being up to 16.5 times. Perception of crime during the night may negatively affect both Bulgarian and Serbian well-being (up to 10 times), while Romanian well-being is mostly affected by the existence of shopping facilities. Finally, the most impactful factors for well-being in North Macedonia refer to cycling safety and scooter accessibility. Full article

In Korea, rural regions increasingly function as peri-urban zones integrated into urban systems. To assess vulnerabilities in these transitional areas characterized by mixed land use and uneven access to infrastructure, this study developed a three-tiered peri-urban livability vulnerability framework by integrating the analytic hierarchy process and the entropy weight method. The results indicated that medical facilities, childcare and education centers, and village communities consistently emerged as key indicators, linking peri-urban livability directly to the stability of settlement environments and the quality of life of residents. Contrastingly, expert evaluations and data-driven outcomes related to road networks and agricultural infrastructure displayed substantial discrepancies, revealing gaps between perceived importance and actual provision levels. Such differences highlight the risk of underestimating infrastructure-related vulnerabilities when subjective assessments are employed exclusively. By synthesizing subjective and objective weights, this study advances urban and environmental analysis and supports evidence-based decision-making for policy prioritization. The findings demonstrate that peri-urban vulnerability is shaped less by productive capacity than by social infrastructure and community stability. This conclusion offers crucial insights for enhancing livability and guiding urban planning strategies. Full article

Differing from traditional isobaric combustion, a pulse detonation-based ramjet (PD-Ramjet) was proposed in this study to enhance the efficiency of traditional ramjets. By using a two-dimensional numerical simulation method, the filling process and detonation initiation process of the hydrogen/air stoichiometric mixture in channels equipped with typical flameholders were studied under the inflow condition of a ramjet combustor, and the influences of the typical flameholders on the filling process and detonation initiation process were analyzed. Single cavity, sudden expansion cavity, central cavity, and V-shaped groove were chosen as typical ramjet flameholders. The simulation and analysis results indicated that the flameholders would affect the filling effect, and the blocking ratio had a great influence on the filling process. The hydrogen volume discharged from the outlet of the channel and the time for mixed gas to reach the outlet were related to the blocking ratio and the cavity aft wall inclination angle. The detonation initiation process revealed that the flameholders promoted the generation of detonation waves. Contrastingly, the detonation wave could not be initiated in the channel without flameholders despite the better filling effect. Moreover, different flameholders would change the position of high-pressure point formation and the time for generating the stable detonation wave. On the whole, the sudden expansion cavity had a lower blockage ratio and also gave consideration to the filling effect and detonation initiation characteristic, making it the most suitable flameholder structure for PD-Ramjet in this study. Full article

Stingless bees, particularly Tetragonula pagdeni, are vital for both ecosystems and the economy due to their pollination services and nest products. However, little is known about their nesting habits. This study investigated the nesting ecology of Tetragonula pagdeni in West Bengal, India. The species was found inhabiting a variety of landscapes, including agricultural, forest, rural, semi-urban, and urban areas, with a greater abundance in rural areas featuring mixed vegetation. Colonies, which were eusocial, perennial, and cavity-nesting, occupied diverse substrates, including tree trunks, building walls, rock crevices, electric poles, and field ridges—tree trunks and walls being the most common. Wild nests were located at heights ranging from 0 to 13.46 m, mostly around 2 m. Nest entrances varied in shape (circular, oval, slit-like, or irregular), with a longest opening axis of 10.50 ± 2.94 mm, and were oriented in multiple directions. Internally, nests measured 198.31 ± 86.36 mm in length and 142.73 ± 17.28 mm in width. Nests featured brood zones surrounded by honey and pollen pots, along with structure-supporting elements like the involucra and pillars. Brood cells were light brown and oval; those for workers and drones were similar, while queen cells were larger. Honey pots were light to dark brown, oval, dome-shaped, or irregular. Each involucrum was a thin, flat sheet, and the pillar was short, narrow, thread-like. These findings offer valuable insights into the distribution, nesting behaviour, and nest architecture of Tetragonula pagdeni, supporting its conservation and sustainable management. Full article

This systematic review synthesizes a decade of peer-reviewed research (2015–2025) examining the interplay of filter bubbles, echo chambers, and algorithmic bias in shaping youth engagement within social media. A total of 30 studies were analyzed, using the PRISMA 2020 framework, encompassing computational audits, simulation modeling, surveys, ethnographic accounts, and mixed-methods designs across diverse platforms, including Facebook, YouTube, Twitter/X, Instagram, TikTok, and Weibo. Results reveal three consistent patterns: (i) algorithmic systems structurally amplify ideological homogeneity, reinforcing selective exposure and limiting viewpoint diversity; (ii) youth demonstrate partial awareness and adaptive strategies to navigate algorithmic feeds, though their agency is constrained by opaque recommender systems and uneven digital literacy; and (iii) echo chambers not only foster ideological polarization but also serve as spaces for identity reinforcement and cultural belonging. Despite these insights, the evidence base suffers from geographic bias toward Western contexts, limited longitudinal research, methodological fragmentation, and conceptual ambiguity in key definitions. This review highlights the need for integrative, cross-cultural, and youth-centered approaches that bridge empirical evidence with lived experiences. Full article