Search Results (1,332)

High-viscosity sodium alginate solutions (4.5% by mass, apparent viscosity 1 × 10⁴–2 × 10⁴ cP) are widely used in the preparation of hydrogels, wet spinning, and biomedical materials. Residual bubbles can cause internal voids in hydrogels, mechanical heterogeneity, fiber breakage during spinning, and reduced strength, and can severely affect the cell compatibility and clinical safety of biomaterials. Due to the difficulty of bubble migration, coalescence, and rupture in high-viscosity systems, traditional vacuum-standing degassing takes up to 24 h and is extremely inefficient, severely limiting the quality of subsequent processing. To address this issue, this study proposes a novel vacuum-assisted centrifugal recirculating degassing method for highly viscous sodium alginate solutions and aims to establish a kinetic framework for describing its overall degassing behavior. Using the number density of bubbles larger than 0.5 mm in diameter as an evaluation metric, we conducted vacuum-standing control experiments and univariate experiments with different screen mesh apertures (5, 1.5, 0.3, and 0.07 mm). We experimentally verified a continuous kinetic model of bubble number decay based on vacuum bubble expansion, centrifugally enhanced migration, and removal probability during the cycle. The results indicate that the bubble removal effect of 40 min of vacuum–centrifugal cyclic degassing is equivalent to that of 4 h of vacuum static settling, representing a 450% increase in degassing efficiency. There is an optimal range for a screen aperture, with the best degassing effect observed at 0.3 mm, achieving a bubble removal rate of 83.69%. The established kinetic model exhibits good fitting accuracy (RMSE = 0.17, MAPE = 5.9%) and can accurately predict degassing efficiency under different process conditions. This study provides a quantifiable, modelable, and optimizable process scheme for rapid degassing of high-viscosity sodium alginate solutions, and offers a theoretical reference for the development of degassing technologies for high-viscosity polysaccharide fluids. Full article

This study aimed to develop and validate a Social–Emotional Competence instrument for college students. The questionnaire includes 30 items across five dimensions: self-awareness, self-management, social awareness, interpersonal communication, and sense of responsibility. The items were selected from an initial pool of 42 items generated through a comprehensive literature review, semi-structured interviews, and expert evaluation. A total of 1008 valid responses were collected from undergraduate students. The dataset was randomly divided into two independent samples. Sample 1 (n = 504) was used for item analysis and exploratory factor analysis, while Sample 2 (n = 504) was employed for confirmatory factor analysis (CFA) and assessing the reliability and validity of the questionnaire. Exploratory factor analysis supported a five-factor structure, accounting for 60.619% of the total variance. Confirmatory factor analysis indicated that the model fit the data reasonably well, with CFI = 0.915, TLI = 0.905, RMSEA = 0.063, and SRMR = 0.046. The questionnaire demonstrated excellent internal consistency (α = 0.958) and maintained strong stability over time, as evidenced by a test–retest correlation of r = 0.939. Criterion-related validity was supported by significant positive correlations with interpersonal competence and negative correlations with emotion regulation difficulties and depressive symptoms. Taken together, these results provide preliminary support for the reliability and validity of the instrument, suggesting that it may serve as a practical tool for evaluating social–emotional competence among college students. Full article

Designing low-voltage (LV) power distribution systems for mass-sensitive electric vehicles involves several unresolved technical challenges, including parasitic $I^{2}R$ losses, excessive mass of commercial off-the-shelf distribution units, and difficulties in isolating thermal phenomena during vehicle operation. In dynamic racing conditions, temperature measurements of LV components are strongly influenced by external heat sources such as traction batteries, motors, and inverters, complicating accurate assessment of conductor self-heating and distribution losses. This work presents a load-driven methodology for the specification, implementation, and validation of LV architectures, demonstrated using a Formula Student electric race car. The proposed approach combines harness current mapping, resistive loss modeling, and component-level topology optimization to support the development of lightweight and electrically robust systems. Within this framework, a mass-optimized programmable solid-state power distribution unit (PDU), an auxiliary battery system with a battery management system (BMS), and an optimized LV wiring harness were developed and experimentally validated through controlled subsystem tests and in-vehicle operation. The proposed methodology enabled reduction in PDU mass by 40–80% relative to commercially available solutions while maintaining programmable protection, integrated current sensing, and stable thermal operation under representative racing loads. This reduction was achieved through load-driven conductor sizing, application-specific protection threshold optimization, and elimination of redundant protection and interconnection hardware. The developed PDU achieved a mass of 155 g with measured channel resistances of 40–70 m$\mathsf{\Omega }$. The auxiliary battery pack exhibited an average internal resistance of 64.2 m$\mathsf{\Omega }$ at a total mass of 2190 g, while the optimized harness demonstrated resistivity in the range of 14.72–33.98 m$\mathsf{\Omega }$/m. Experimental validation confirmed stable operation below critical thermal limits under both nominal and off-nominal load conditions. The obtained results demonstrate that the proposed methodology enables measurable reductions in both system mass and resistive power losses through application-specific optimization of the LV architecture. However, the presented approach is primarily suited for motorsport and other highly mass-constrained applications, where reduced packaging volume, efficiency, and weight justify the increased design complexity and lower universality compared to commercial off-the-shelf solutions. Full article

This study examines the psychometric functioning of the Basic Learning Ability Assessment (BLAA), a high-stakes placement assessment used in Taiwan’s Adaptive Guidance Placement System (AGPS) for junior high school students with intellectual disabilities (IDs). The sample comprised 203 ninth-grade students with ID from 47 public junior high schools in Taiwan, all of whom completed three operational multiple-choice forms of the BLAA. Using classical test theory (CTT), we examined item difficulty using proportion-correct indices, item discrimination using upper–lower group discrimination indices, distractor functioning by comparing response patterns between higher- and lower-performing examinees, and internal consistency reliability using the Kuder–Richardson Formula 20 (KR-20). The results show that most items fell within the average-to-easy range and demonstrated acceptable to strong discrimination. Distractor functioning was generally satisfactory, with most items containing no nonfunctioning distractors. KR-20 coefficients ranged from 0.904 to 0.926, indicating high internal consistency within each form. Functional Language and Social Adaptation showed relatively stable psychometric patterns, whereas Mathematical Skills displayed greater variability in item difficulty, discrimination, and distractor functioning. Overall, the findings provide initial CTT-based internal psychometric evidence regarding the item functioning and form-level reliability of the BLAA, while highlighting the need for ongoing item refinement, particularly in the Mathematical Skills domain. Full article

Introduction: The invasive European catfish (Silurus glanis) is actively spreading across Iberian freshwaters, with no effective management measures in place to control its growing abundance or prevent its establishment in new localities. It poses a severe threat to endemic and already endangered species, and is simultaneously a preferred target by few anglers who continuously promote its spread. The LIFE-PREDATOR project aims to stop the spread of European catfish in lentic systems in Portugal and Italy, particularly in protected areas. Objectives: This talk will present the mid-term results of the LIFE-PREDATOR in Portugal, and discuss the difficulties and future challenges to reduce the size of local populations of European catfish. Methodology: The LIFE-PREDATOR team developed several tasks in Portugal: (1) established the reference situation of fish communities in six reservoirs in the Tagus Basin, using scientific fishing, fish telemetry and eDNA-based tools; (2) determined the optimal protocols for sampling catfish; (3) implemented an early detection programme based on warning teams, data-mining and eDNA tools; (4) developed population control actions in four reservoirs; and (5) organised dissemination events for the general public, anglers, and students from kindergarten to university levels. Results: Overall, there is a grim view about recipient communities in the studied lentic systems, which tend to be dominated by invasive fish species, including common carp (Cyprinus carpio), gibel carp (Carassius gibelio), European catfish, pikeperch (Sander lucioperca), European perch (Perca fluviatilis) and largemouth bass (Micropterus nigricans). At least three new localities harbouring catfish were identified from online data-mining and warning teams. A total of 8 tons of catfish were removed by mid-June of 2025, mostly from the Natural Park of International Tagus. Outreach activities were conducted in nearly 60 schools, reaching more than 5000 students. Moreover, 67 general public events have reached more than 4500 people since the project started (September 2023). Conclusions: Despite its positive outcomes, the LIFE-PREDATOR team has encountered challenges in engaging key stakeholders such as anglers, involving local municipalities, and implementing catfish removal actions in remote areas. Difficulties and challenges in catfish management must therefore be debated in order to assure the after-LIFE implementation across Portuguese protected areas. Full article

Background and Objectives: The neurocognitive sequelae of COVID-19 have attracted attention as part of post-COVID condition (PCC), yet standardized tools for screening and quantifying PCC-related cognitive impairment remain scarce. The present study aimed to develop and validate the Screening for Neurocognitive Abilities Post-COVID (SNAP-COVID), a self-report questionnaire designed to capture current symptom burden and perceived changes in cognitive functioning relative to pre-COVID status in a Greek-speaking sample. Materials and Methods: Data collection occurred in three phases between August 2024 and February 2025. Dataset A (N = 27) was used for test–retest reliability. Dataset B (N = 300) was used for exploratory factor analysis (EFA), reliability testing, and convergent validity analyses with the Brain Fog Scale (BFS). Dataset C (N = 317) was used for independent validation through confirmatory factor analysis (CFA). Results: Initial EFA of the 30-item SNAP-COVID scale suggested a four-factor model, yet further item refinement yielded a robust three-factor, 24-item solution: (1) General Cognitive Functions (17 items, α = 0.948), (2) Sensory Hypersensitivity (4 items, α = 0.829), and (3) Language and Communication (3 items, α = 0.950). The total scale demonstrated excellent internal consistency (α = 0.95). Convergent validity was evident by significant correlations between SNAP impact scores and BFS scores (r = −0.442, p < 0.001). CFA confirmed the three-factor structure with acceptable fit indices (χ²(249) = 677.29, p < 0.001; CFI = 0.882; TLI = 0.869; RMSEA = 0.074; SRMR = 0.032). Conclusions: The SNAP-COVID scale is a reliable and valid instrument. Its multidimensional structure captures global and domain-specific difficulties, addressing a critical gap in post-infectious cognitive assessment. Full article

Background: Burn injuries are increasingly being recognized as chronic conditions with long-term physical, emotional, and social consequences. As survival after acute burn trauma improves, greater attention has shifted toward health-related quality of life (QoL) in survivors, particularly in regions where data remain limited. Methods: This study included burn survivors treated between January 2022 and December 2023 in the Department of Plastic Surgery and Reconstructive Microsurgery of the Emergency Clinical Hospital “Bagdasar-Arseni,” Bucharest, Romania. Patients who survived hospitalization and follow-up were invited to complete a Romanian-adapted version of the Burn Specific Health Scale-Brief (BSHS-B). Demographic and clinical data were collected from medical records, including burn type, total body surface area (TBSA), burn depth, burn localization, and access to rehabilitation services. Statistical analysis included descriptive methods, chi-square tests, t-tests, Kendall’s tau-b, Cramer’s V, Cronbach’s alpha, and exploratory factor analysis. Results: Thirty-eight patients were included. Most burns were thermal (94.74%), while burns involving <10% TBSA were most frequent (60.53%). Functional outcomes were generally favorable, with most patients reporting no difficulty in basic daily activities such as bathing, dressing, and writing. However, fine motor activities and return to previous work were more frequently affected. Emotional recovery appeared less complete, with persistent mild-to-moderate loneliness, sadness, and emotional distress reported by many participants. Women reported higher levels of loneliness (p = 0.015), while third-degree burns were associated with more frequent depressive symptoms (p = 0.008). Depressive symptoms were also significantly associated with functional limitations (such as getting dressed, p = 0.002) and work impairment (p < 0.001). The adapted functional and emotional subscales showed excellent internal consistency. Conclusions: Post-burn recovery extends beyond physical healing. Although most patients regained functional independence, emotional distress and occupational difficulties often persisted. These findings support the need for multidisciplinary long-term burn care integrating physical rehabilitation, psychological screening, and psychosocial support. Full article

To address the difficulty of directly measuring the internal conductor temperature and the complex influence of external environmental factors on gas-insulated switchgear (GIS), a three-dimensional thermal–fluid multiphysics coupling model was developed for a 110 kV three-phase common-enclosure GIS disconnect switch. The model incorporates contact resistance heating, natural convection of SF₆ gas, wind speed, and solar radiation. The effects of contact resistance and environmental factors on the temperature field distribution were systematically investigated. The results show that an increase in contact resistance significantly raises the conductor temperature, while higher wind speeds effectively reduce the temperature rise of the equipment. Solar radiation substantially increases the enclosure temperature, whereas ambient temperature has little influence on temperature rise. Based on the enclosure temperature rise, a conductor temperature-rise prediction model and a multi-factor correction model were established. Validation results indicate that all models achieved coefficients of determination greater than 0.98, with prediction errors controlled within ±2 °C. The proposed method enables the accurate prediction of conductor temperature under complex environmental conditions and provides technical support for condition monitoring and overheating fault diagnosis of GIS equipment. Full article

The higher the rotational speed of the telescope dome, the greater the vibration and noise are induced, which results in a more significant impact on telescope imaging performance, while also requiring greater driving power and increasing the control complexity. Therefore, this paper primarily focuses on appropriately reducing the dome speed during high-speed space target tracking without affecting observation effectiveness. First, the initial tolerance of the dome opening in the telescope’s horizontal state is introduced, and the variation pattern of the initial tolerance with the telescope’s elevation angle is derived; then, the angular velocity relationship between the dome and the telescope is established, and the rotational trajectory of the dome is replanned. Taking the International Space Station as an example for simulation, the results show that the maximum velocity of the dome is reduced by 25.4% compared with that of the telescope, with no field-of-view obscuration during the entire observation process. Finally, a multi-motor servo control system for the dome is designed, and practical tests demonstrate that during synchronous tracking with the telescope, the synchronization error PV of all motors is less than 2.5%, the dome tracking accuracy is better than 60″, and the maximum dome speed is reduced by approximately 33.3% compared with the telescope. This research is of great significance for appropriately reducing the dome speed requirement, alleviating high-speed vibration and noise, and simplifying control difficulty in high-speed tracking. Full article

Wearable inertial sensors offer a portable alternative to laboratory-grade force plates for postural stability assessment; however, their validity across progressively challenging balance tasks remains under-explored. This study evaluated the reliability and concurrent validity of inertially sensed metrics compared with force-plate-derived postural sway metrics across a five-level spectrum of unstable surfaces (Floor, Foam Pad, Rotating Disc, Air Disc, Bosu). Twenty-five healthy young women (22.1 ± 3.6 years, 1.64 ± 0.04 m, 58.44 ± 8.21 kg) performed five trials of single-leg standing (40 s each) on each surface. Postural sway was computed from antero-posterior (AP) and medio-lateral (ML) center of pressure (CoP) recordings using a force plate (Kistler, 9286 AA, Winterthur, Switzerland, sampling at 500 Hz) in synchronization with a lateral shank-mounted inertial sensor (Bionomadix BN-ACCL3, Biopac Systems, Inc., Santa Barbara, CA, USA, sampling at 100 Hz). In addition to reliability, a two-tiered analysis evaluated global concordance (unstandardized slopes) and method agreement (standardized z-scores). Intraclass correlation coefficients (ICCs) for the inertial sensor were excellent (range: 0.95–0.96), surpassing the force plate (range: 0.85–0.92) as trials accumulated. Analysis revealed moderate-to-good global concordance in the AP direction (r = 0.60, p = 0.001) and good-to-excellent in the ML one (r = 0.85, p < 0.001), validating the progressive intensifying effect of the surface graduation. Individual ranking agreement—evaluated via standardized z-scores—was also significant in both the AP (r = 0.61, p < 0.001) and the ML (r = 0.85, p < 0.001) directions, indicating a convergence into how the two modalities rank individual performance. Bland–Altman plots confirmed high absolute agreement between standardized scores, though a predictable proportional bias was observed in raw units, where the inertial sensor’s underestimation of sway magnitude increased linearly with task difficulty. The five-level postural challenge graduation is a highly reliable framework for balance assessment. While the shank-mounted sensor exhibits proportional underestimation of sway magnitude compared to the CoP at extreme intensities, its high internal stability and sensitivity to task difficulty make it a valid and robust tool for longitudinal clinical monitoring. Full article

South Korea has been advancing the National Digital Twin Land initiative; however, many existing urban digital twin projects have relied on non-standard, visualization-oriented datasets, thereby encountering persistent difficulties in securing interoperability and reusability. In particular, the lack of a standardized methodology capable of systematically fusing fragmented public administrative data with 3D geospatial information remains a major barrier to the practical use of digital twins in administrative operations. To address this gap, this study proposes a standardized urban digital twin data construction methodology that complies with the international standard while effectively accommodating Korea’s building-related public datasets. Specifically, the OGC CityGML Building module is adopted as the reference model, and an extension is implemented to design a data model that extends and integrates heterogeneous sources—such as building height records, building register attributes, and road-name address data—within a unified standard schema. Furthermore, using Busanjin-gu, Busan Metropolitan City, as a case area, we develop high-precision LoD 1~4 building objects from aerial surveying outputs and empirically validate an end-to-end workflow by loading and visualizing the resulting dataset on a national public platform. By constructing operational digital twin data that tightly couples physical geometry with administrative semantics and verifying its feasibility in an actual platform environment, this study establishes a practical, standards-based foundation for deploying and operating geospatial digital twins in smart city and related urban governance applications. Full article

In recent years, with the continuous development of the global economy, maritime transportation has become an essential mode of transportation for both domestic and international trade, making it an urgent task for countries around the world to improve the intelligence level of maritime traffic management. As a key technology in real-time vessel monitoring, traffic hazard early warning, and traffic flow estimation, vessel trajectory prediction has been widely applied across both civil and commercial sectors. To address the problems with existing trajectory prediction methods, such as difficulty in establishing real-time vessel kinematic models, limited understanding of vessel navigation strategies, and poor adaptability for long-term prediction, this paper proposes a deep reinforcement learning-based vessel trajectory prediction method. Firstly, the trajectory prediction problem is formulated as a Markov Decision Process (MDP), thereby transforming the prediction problem into an optimal policy-solving problem of the MDP. Secondly, given the complexity of the trajectory prediction problem, a convolutional neural network (CNN) is adopted to parameterize the policy network, and a CNN-PPO deep reinforcement learning method is used to learn the target vessel’s navigation strategy from historical trajectories. Comparative experimental results show that the proposed algorithm is not only suitable for predicting the target’s position at a specific future moment but also offers clear advantages in trajectory prediction across multiple future moments. Full article

Methane emission reduction represents a critical pathway for near-term climate mitigation. Super-emitter control is widely recognized as the most cost-effective mitigation strategy; however, the prevalence of these sources varies significantly across countries and sectors, resulting in heterogeneity in abatement difficulty and policy priorities. In this study, we integrate recently emerging satellite-based point-source emission datasets to develop a cross-scale analytical framework that systematically characterizes methane emission rate distributions across countries and sectors. Analysis of the full Carbon Mapper dataset shows that sources exceeding 5000 kg h⁻¹ account for only 3.34% of total point sources, yet contribute more than 25.18% of total equivalent emissions. Gini coefficients range from 0.46 to 0.60 across countries, indicating pronounced inequality in emission distributions and mitigation costs. Integrating these distributional characteristics with economic capacity indicators further shows that countries with highly concentrated, high-intensity point sources—particularly oil- and gas-dominated nations such as Turkmenistan and Uzbekistan—offer the highest cost-effective mitigation potential and should be prioritized as global methane action breakthroughs. Among these, economically advanced countries are positioned to lead by demonstration, while nations with high mitigation potential but limited economic capacity represent optimal targets for international climate finance and technology transfer. These findings provide satellite-derived evidence to inform differentiated, country- and sector-specific mitigation pathways. Full article

Background: The involvement of people living in situations of vulnerability has long been a central ethical issue in research, particularly in contexts marked by power asymmetries, limited access to resources, or restricted decisional autonomy. Although international ethical frameworks offer increasing guidance on protecting vulnerable participants, applying these principles in everyday research practice remains challenging, especially in qualitative and multi-country studies. This communication draws on the experience of the European Protecting You & Others project, an Erasmus+ initiative conducted across five countries. Methods: During the project design and implementation, the research team engaged in ongoing reflexive work to examine the ethical, methodological, and practical challenges encountered when defining vulnerability, involving participants living in situations of vulnerability, and adapting research activities and educational interventions to different specific needs. Reflexive notes and collective team discussions were used to identify recurrent challenges and the strategies adopted to address them. Results: Key challenges included (a) the difficulty of choosing an inclusive yet operational definition of vulnerability; (b) participants’ self-perceptions and tensions between externally assigned vulnerability; (c) risks of stigmatization associated with categorization; the use of respectful and context-appropriate language; and (d) the adoption of a shared international framework adapted to educational content across countries. Overall, vulnerability emerged as a dynamic and context-dependent condition that requires research designs, methodologies and interventions to remain open, flexible, and responsive throughout the study process. Conclusions: Studies involving people living in situations of vulnerability, particularly in international and multi-country contexts, should not rely solely on predefined classifications or standardized safeguards. Instead, adaptive procedures are needed to recognize how needs, barriers, resources, and forms of participation vary across individuals and contexts. Such openness may support more person-centered approaches to engagement, communication, and intervention adaptation, while preserving ethical consistency and methodological rigor across countries. Full article

Adolescent self-harm, particularly non-suicidal self-injury (NSSI), is increasingly understood as a multidetermined behavior shaped by emotional, cognitive, and interpersonal processes. This focused, non-systematic narrative review examines cognitive–affective correlates of adolescent non-suicidal self-injury, while drawing on broader self-harm and suicidality-related evidence only where relevant to the cognitive–affective formulation. Particular attention is given to executive functioning, emotional processing, and social–emotional and interpersonal cognition. The evidence is strongest for emotional processing, especially difficulties in emotion regulation, rumination, cognitive reappraisal, alexithymia, and the identification and modulation of internal states. Executive functioning also appears clinically relevant, but the current findings support a selective rather than global impairment account, with the clearest evidence involving inhibitory control, impulsivity-related regulation, and decision-making under affective pressure. Social–emotional and interpersonal cognition is treated as an emerging and indirectly supported domain; much of the available evidence concerns interpersonal and relational constructs, such as interpersonal sensitivity, relational interpretation, emotional communication, and family–emotional context, rather than direct measures of theory of mind, social inference, or emotion recognition accuracy. Overall, adolescent self-harm is best understood as emerging from the interaction of emotional dysregulation, weakened behavioral control under distress, and difficulties in social–emotional meaning-making during a developmentally sensitive period. A cognitively informed developmental framework may help refine theory, improve clinical formulation, and guide future mechanism-oriented research. Full article