Search Results (34,029)

In rural areas affected by Chernobyl, accelerated erosion has become a major source of particulate ¹³⁷Cs in sediment load. The long-term dynamics of the activity concentration in eroded soil material transported from individual slope catchments can be better understood by exploring the ¹³⁷Cs depth distribution in sediments deposited near cultivated fields. This study focuses on three cultivated slope catchments located in the Chernobyl-affected area of Central Russia. A depth incremental campaign was conducted within zones of sediment accumulation in 2022–2025. The behavior of radiocaesium associated with particles after the Chernobyl accident was controlled by the prompt implementation of remediation measures. Shortly after the accident, the values decreased by more than two times. The radionuclide flux then began to depend on soil erosion processes. Gradually, the thickness of the upper soil that had been eroded became large enough to allow soil material from deeper layers to be involved during ordinary plowing and led to a subsequent decrease in the ¹³⁷Cs activity concentration. Given the decreasing snowmelt runoff and lack of increase in high-intensity rainfall in the 21st century, the activity concentration of ¹³⁷Cs in slope runoff has remained quite stable. This phenomenon requires consideration of whether a physically based model for the transport of particulate radionuclides should be developed. Full article

Ice adhesion on exposed structures remains a major operational challenge, motivating the search for passive, material-based anti-icing strategies. Molecular dynamics offers a controlled way to investigate ice–surface interactions beyond the limits of experimental setups. In this work, we develop a simulation framework to model the impact of solid hexagonal ice droplets on metallic substrates. Ice impacts are simulated across a range of velocities (10–120 m/s), temperatures (120–250 K), and face-centred cubic surface materials (gold, copper, silver, aluminum, and nickel). Using LAMMPS, mW water force-field, EAM/Alloy metal potentials, and Lennard-Jones water–surface interactions, we quantify phase evolution through angular order parameter and quasi-liquid layer measurements, complemented by the CHILL+ algorithm in OVITO. By isolating all external factors, we show that melting increases with velocity and temperature and correlates with substrate properties: metals with high thermal diffusivity and low Young’s modulus tend to decrease post-collision ice melting. The ratio of the former to the latter, a derived index of merit Υ, significantly correlates with melting percentage and identifies silver as the most effective anti-ice material examined. Statistical analyses strongly suggest that these surface properties influence interfacial melting, supporting the use of this modelling framework for screening and designing anti-icing materials. Full article

With global warming and accelerated urbanization, building air-conditioning (AC) releases more heat into the environment, exacerbating the urban heat island (UHI) effects and increasing building cooling energy consumption. Existing research has limited quantification of the impact of air-conditioning anthropogenic heat (ACAH) on the cooling energy consumption of different types. This study aims to explore the distribution characteristics of ACAH and its impact on residential building energy consumption. Firstly, typical residential buildings in the Pearl River Delta region were selected as a case study. Field experiments were conducted to measure temperature and humidity at 0.5 m, 1 m, 2 m, and 3 m from the outdoor unit, alongside ambient temperature and wind speed. Three grid densities were applied to verify the CFD model, with a prediction error of less than 0.3 °C at 0.5 m under a medium grid. The simulated temperature at 1 m from the outdoor unit under calm wind conditions was compared with field measurements to reveal the horizontal and vertical distribution characteristics of ACAH. Secondly, the effects of different building shapes, ambient temperatures, and wind speeds on the spatial distribution of ACAH were investigated. Finally, EnergyPlus (V23.1.0) was employed as the building energy simulation software, with its microclimate coupling interface implemented via Python scripts to quantify cooling energy consumption variations across different building floors under ACAH influence. Results indicated that ACAH exhibits significant horizontal non-uniformity, exerting the greatest impact within a 0.5 m radius (affected air temperature 4.3 °C higher than ambient). Vertically, localized heat accumulation occurs in the building’s central area, with air temperature 3.5 °C higher than at the bottom. Furthermore, compared to fixed meteorological conditions, the cooling energy consumption difference across floors considering ACAH reaches approximately 7.8%. This study provides accurate meteorological boundary conditions for building energy assessment and supports microclimate management in residential areas. Full article

Promoting farmers’ adoption of low-carbon technologies constitutes a vital pathway for achieving agricultural sustainability and a key measure for implementing the national dual-carbon strategy. Drawing upon field survey data from 602 wheat farmers in Heze City, Shandong Province, this study employs an ordered probit model to empirically examine the influence mechanism of data capital on farmers’ low-carbon technology adoption behaviour. The results show that (1) data capital significantly promotes farmers’ adoption of low-carbon technologies; (2) ecological cognition plays a significant mediating role, while economic incentives and human capital serve as positive moderators; (3) heterogeneity analysis indicates that the promoting effect of data capital is more pronounced among large-scale farmers. Based on these findings, recommendations are proposed to consolidate rural digital infrastructure, establish agricultural data service platforms, and enhance farmers’ ecological cognition, thereby fully unleashing the potential of data capital in driving agricultural sustainability. Full article

Noble metal nanostructures provide versatile platforms for light manipulation through localized surface plasmon resonances (LSPRs). Among them, triangular silver nanoplates (AgNPTs) exhibit strong field-enhancement and spectral tunability, yet assembling them reproducibly on solids is challenging. We report a two-step functionalization strategy for constructing ordered AgNPT dimers on silica substrates, combining 3-aminopropyltriethoxysilane (APTES) anchoring with 1,4-butanedithiol bridging. AFM reveals face-to-face dimers with well-defined sub-nanometer gaps. Large-area AFM statistics collected over multiple regions (N = 80 nanoplates per condition) confirm reproducible and selective vertical dimerization. Extinction spectroscopy reveals sequential dielectric and coupling effects: thiol adsorption red-shifts the main resonance from 700 to 780 nm because of increased local refractive index and near-field damping, whereas dimerization partially restores it to ≈750 nm, consistent with plasmon hybridization within rigid ∼0.7 nm molecular gaps, where nonclassical moderation may occur but classical hybridization fully explains the observed shifts. Concomitantly, the extinction intensity doubles, following an exponential growth toward saturation during assembly. Surface-enhanced Raman scattering (SERS) measurements using 4-mercaptobenzoic acid (4-MBA) confirm a fourfold increase in the SERS enhancement factor from monolayer to bilayer, consistent with near-field coupling and hotspot formation at interplate junctions. Quantitative plasmon sensitivity analysis yields comparable results between experiments and finite-difference-time-domain simulations, confirming that the observed spectral shifts arise from near-field coupling and dielectric modulation rather than ensemble effects. This reproducible methodology enables precise tuning of NPT orientation, spacing, and optical response, providing a robust platform for enhanced sensing, SERS, and nanophotonic device engineering. Full article

Pinus clausa var. clausa (Chapm. ex Engelm.) Vasey ex Sarg., sand pine, is the dominant tree of biorich but ecologically compromised Southeast Florida scrub. Scrub habitats and P. clausa have dwindled due to habitat reduction and fragmentation, regional development, and fire suppression. The purpose of the present article was to seek correlates of P. clausa establishment under present unnatural development-impacted conditions using 428 field measurements at four sites to determine spatial positioning preferences relative to vegetation edges, then adding 120 measurements at a single site aimed at evaluating several potential predictors of P. clausa establishment. Potential establishment predictors were adjacency to other woody plants, depth to hard sand horizon, seed tree distance and direction, light-intensity, soil-core color, soil pH and soil surface firmness. Comparing frequency distributions of juvenile P. clausa locations with frequency distributions of random spots within the same perimeters, juvenile pines tended toward adjacency to other woody plants (chi² p < 0.0001), toward shallow hard horizons (Kolmogorov–Smirnov p = 0.0006), toward soft soil surfaces (K–S p = 0.007), and toward proximity to seed trees (K–S p = 0.004). Additionally, juvenile P. clausa were often clustered under groves of Quercus geminata Small with comparatively thin canopies. Bayesian logistic regression showed adjacency to woody plants as a strong predictor of P. clausa establishment. When alongside other plants, P. clausa establishment was mostly on the north or east side of neighboring plant edges. Overall conclusions were that juvenile Pinus clausa in SE Florida scrub fragments is sensitive to positioning relative to other woody plants, and is associated with soil surface softness, soil depth to hard horizon, and light levels, except as seedlings. Full article

Purpose: The primary aim of the present study was to examine the extent to which participation in organized youth basketball training contributes to physical activity across intensity zones during training sessions in relation to biological maturation status. Methods: Participants were classified into three maturity groups based on predicted age at peak height velocity (PHV): −2.5 to −1.5, −1.5 to −0.5, and ≥−0.5 to 0.83 years from PHV. Data from two training sessions per participant were averaged to obtain representative individual values. One-way analyses of variance (ANOVAs) were used to examine differences in anthropometric, physical performance, and field performance variables between PHV groups. Physical activity patterns were analyzed using two-way mixed-design ANOVAs with PHV stage as the between-subject factor and intensity zone (MET- and HRR-based) as the within-subject factor. Results: Across all maturity groups, approximately 10–17% of total training time was spent in light-intensity activity, while the majority of time was accumulated in moderate-to-vigorous intensity zones (approximately 35–50%, depending on the classification method). Significant maturity-related differences were observed in anthropometric variables and physical performance measures, with more mature players demonstrating superior sprint performance, jumping ability, and grip strength. Field performance indicators also differed between PHV groups, with more mature athletes exhibiting higher external and internal training loads. In contrast, no significant interactions or main effects of PHV stage were observed for physical activity intensity distribution. Conclusions: Organized basketball training contributes substantially to moderate-to-vigorous physical activity accumulated during training sessions. However, these findings reflect training-specific activity and should not be interpreted as representing total daily physical activity. No differences in activity intensity distribution were observed between maturation groups, although this finding should be interpreted with caution, given methodological limitations. These results highlight the need to consider biological maturation when designing youth training programs. Full article

The measurement of the magnetic field generated by a flowing current constitutes a non-invasive sensing technique for online energy consumption monitoring. In this work, based on the use of low-cost linear Hall effect sensors, a low-form-factor custom contactless ammeter probe is presented. The differential configuration of the sensor module and the subsequent fully digital programmability in range and sensitivity, together with the included self-calibration and compensation circuits for mismatching, managed by a microcontroller, allow for optimum detection for both continuous and mains current with a resolution of 10 mA for input ranges of 2 A. The proposed ammeter power consumption and measurement accuracy in different scenarios are tested, including the power monitoring of an IoT-based device, obtaining results matched to those featured by a commercial oscilloscope current probe, which validates its suitability and reliability as autonomous low-cost probe for portable contactless power monitoring. Full article

This study investigates tension-induced stress in Cross-tensioned Concrete Pavement (CTCP) during sequential tensioning. An integrated approach combining full-scale field testing and finite element analysis was employed. A field test was conducted to capture the stress distribution throughout the complete tensioning process, and a finite element model was subsequently developed and validated against measured strains. The results indicate that the maximum tensile stress (approximately 1.35 MPa) consistently occurs at the corner of the nearest anchorage zone, which can be completely offset by the compressive stress generated from subsequent tensioning operations. The concept of “prestress effect zone” is proposed to characterize the influence region of each tensioning sequence. In CTCP, the extent of this zone is expected to be influenced by the characteristics of the applied prestress force, including tendon angle, spacing, and magnitude. Based on the distinct tension-induced stress distribution characteristics along the slab, three zones are identified: tensile increase region, tensile stability region, and tensile decrease region, enabling clearer investigation of tension-induced stress. The observed superposition of tensile stresses during sequential tensioning operations highlights the importance of analyzing the development of tension-induced stress throughout the tensioning process, providing essential guidance for anchorage zone design and construction procedures. Full article

Reliable last-mile connectivity at the cell edge remains a central challenge for Advanced Metering Infrastructure (AMI) in smart grids. This work addresses how to select between LTE-M and NB-IoT communications under weak-coverage conditions by combining field measurements with distribution-based channel modeling. We analyze multi-month Reference Signal Received Power (RSRP) datasets from three areas of a real AMI deployment (N = 30, 35, and 38 m, respectively) and fit canonical fading surrogates—Rayleigh, Rician, and Nakagami—to the normalized measurements. The principal decision statistic is the probability that RSRP falls below a practical threshold (−105 dBm), obtained from empirical and modeled CDF and translated into the predicted number of meters requiring fallback to NB-IoT. Across areas, Nakagami consistently provides the lowest or near-lowest Root Mean Square Error (RMSE) against empirical CDF and the closest agreement with observed fallback counts at −105 dBm, whereas Rayleigh tends to underestimate deep fade tails and Rician degrades when line-of-sight is weak. A threshold sweep sensitivity study (−110 to −89 dBm) using Area 3 illustrates how the predicted fallback population changes monotonically with the decision threshold and supports policy tuning. Overall, a CDF-anchored, Nakagami-guided rule at −105 dBm aligns technology selection with measured channel statistics, improving the robustness of Cellular IoT (CIoT) last-mile communications. Full article

The synergistic effects of soil acidification and heavy metal pollution present major challenges for global agroecosystems. To systematically trace the evolution of research and identify key topics in this field, this study employed CiteSpace to visualize and analyze 691 records from the China National Knowledge Infrastructure (CNKI) and 6747 highly relevant articles or reviews from the Web of Science (WOS) Core Collection database from 2005 to 2025. The results indicate a steady to rapid rise in global publications, with China contributing the largest share, at 2468 publications. This has produced a research cluster centered around the Chinese Academy of Sciences (CAS); however, the centrality of its international cooperation remains limited. Studies in the CNKI database are driven by agricultural needs, focusing on national food security, rice yield stability, improvement of arable land, and heavy metal passivation and remediation, with a concentration on basic agricultural science. By contrast, research in the WOS database emphasizes fundamental mechanisms and interdisciplinary integration, addressing aluminum toxicity, microbial communities, the nitrogen cycle, and global climate change, intersecting fields such as environmental science, soil science, ecology, and microbiology. The evolution of research hotspots shows a clear trajectory: from acidity regulation and chemical speciation analysis of heavy metals (2005–2013), to heavy metal passivation, remediation, and phytoremediation (2014–2018), and then to biochar materials, microbiome analysis, and the synergistic role of carbon sequestration (2019–2025). This study argues that future research should move beyond single remediation measures and adopt integrated strategic management to jointly improve bioremediation efficiency, promote soil carbon sequestration and soil health, and enhance microbial adaptation to global climate change. Full article

Multi-line-scan camera systems provide high-frequency sampling and wide field-of-view coverage, making them valuable for three-dimensional measurement and dynamic reconstruction. However, their one-dimensional projection property introduces scale ambiguity and strong parameter coupling during calibration, which limits the consistency and stability of local optimization in multi-camera systems. To address this issue, this paper proposes a global calibration method based on physical constraints and hierarchical optimization. A unified imaging and motion model is constructed by incorporating physical scale constraints and structural priors, and geometric scale information is introduced into the joint optimization to reduce scale ambiguity and parameter coupling. Parameter normalization and staged optimization are further adopted to improve numerical stability for variables of different magnitudes and enable consistent estimation of multi-camera parameters within a unified framework. Simulation and experimental results show that the method achieves stable convergence under focal-length initialization perturbation, baseline deviation, and noise interference, with a three-dimensional reconstruction error below 0.67 mm and a convergence probability of at least 99.7%. These results indicate that the proposed method effectively reduces calibration uncertainty in multi-line-scan camera systems and supports high-precision online measurement and dynamic three-dimensional perception. Full article

This paper proposes a numerical method combining a fixed-point harmonic balance finite element method (FEM) with a dynamic hysteresis model to accurately calculate the loss distribution of laminated cores under complex operating conditions. This method primarily employs the frequency-domain FEM to solve the magnetic field distribution of silicon steel laminated cores under various excitations, including power frequency multi-harmonic conditions. The resulting magnetic flux density distribution is substituted into the dynamic hysteresis model, enabling the accurate simulation of the hysteresis loop at any position of the laminated core. Hence, the loss distribution of the laminated core can be obtained. Compared to the modified Steinmetz formula, the proposed method is validated with better performance. The relative error is less than 6% between the measured and the calculated core losses of the proposed method. These results can improve the accuracy and efficiency of transformer iron loss calculation in engineering applications. Full article

Assessing individual animal health is essential for detecting early ecological stress that may scale to population-level impacts. Yet, conventional capture-based methods are invasive and logistically challenging, particularly for large mammals. This study evaluates the accuracy of drone-based morphometric measurements as a non-invasive approach for estimating elephants’ Body Condition Index (BCI). Research was conducted in Way Kambas National Park, Sumatra, using a DJI Matrice 300 RTK equipped with a multisensor camera to acquire aerial imagery, primarily from a top-down perspective. Morphometric parameters were extracted through image preprocessing, segmentation, and edge detection using an OpenCV-based Canny algorithm, followed by coordinate and Euclidean distance analyses. Drone-derived measurements were validated against field-based morphometry in captive Sumatran elephants. Linear regression revealed strong agreement between methods, with R² values ranging from 0.91 to 0.97. Mid-body width showed the highest accuracy (R² = 0.97, MAPE = 2.66%, RMSE = 2.36), while other body dimensions also performed consistently well. BCI-related morphometric ratios exhibited minimal differences between drone and field measurements, confirming methodological reliability. As an exploratory extension, a preliminary allometric scaling framework was applied to estimate body condition proxies in free-ranging wild elephants except for mid-body width; however, these estimates are model-derived from total body length and should be interpreted as indicative rather than as direct morphometric assessments of body condition. These findings demonstrate that drone-based photogrammetry provides a validated, practical, and non-invasive method for morphometric measurement in captive elephants, with promising but as yet incompletely validated potential for application to wild populations. Full article

Postsecondary institutions are seeing an increased prevalence of student mental health concerns and disabilities, highlighting the need for campus-based approaches that support student well-being. While college campuses provide many services to support students, occupational therapists are largely absent from these support systems, despite growing interest in this emerging field of practice. This program description and implementation case study examines preliminary indicators of feasibility for the WILL Thrive program, which delivered occupational therapy (OT) services on a college campus through a Level II fieldwork placement. Feasibility was examined across domains of acceptability, demand and implementation using an integrated approach combining a needs assessment, service development and process evaluation. Data sources included environmental observations, surveys, stakeholder interviews and process evaluation measures, including service delivery tracking, referral patterns, and resource utilization. Referrals and service utilization in this case were most frequently observed among students reporting neurodevelopmental and mental health-related functional challenges, providing preliminary indicators of potential service users, though a small, heterogeneous sample size limits generalizability. Referral patterns and engagement from the wellness center and accessibility staff highlight preliminary strengths of the program, including early indicators of acceptability and demand. In contrast, implementation barriers were also identified, including limited campus-wide understanding of the OT scope and role and constraints in on-campus OT supervision. Findings offer early, exploratory signals of feasibility for integrating OT services through an OT fieldwork II model and suggest that OT may complement existing campus supports by addressing participation-focused, functionally orientated needs. Results should be viewed as preliminary and inform future implementation studies that include systematic outcome measures, comparative analysis with existing services, and broader assessment across diverse higher education contexts. Full article