Search Results (1,719)

Monitoring water quality is critical for protecting freshwater ecosystems and supporting sustainable water resource management. Lake Tana, Ethiopia’s largest freshwater lake, faces increasing agricultural and urban pressures, while conventional monitoring remains costly and spatially constrained. This study developed an integrated Sentinel-2 remote sensing and machine learning framework to estimate chlorophyll-a (Chl-a), turbidity (TU), total nitrogen (TN), and total phosphorus (TP) using 858 in situ observations and Google Earth Engine. Random Forest (RF), Extreme Gradient Boosting (XGB), Artificial Neural Networks (ANN), and Support Vector Regression (SVR) were evaluated using spectral bands, band combinations, and indices. RF provided the best predictions for Chl-a (R² = 0.94 ± 0.01; RMSE = 2.11 ± 0.18 µg L⁻¹; MARE = 5%) and TP (R² = 0.91 ± 0.01; RMSE = 0.26 ± 0.01 mg L⁻¹; MARE = 8.7%), whereas XGB performed best for TU (R² = 0.93 ± 0.01; RMSE = 5.17 ± 0.43 NTU; MARE = 7%) and TN (R² = 0.94 ± 0.02; RMSE = 0.18 ± 0.02 mg L⁻¹; MARE = 9.9%). The strong predictive performance of RF and XGB across both optically active and inactive parameters demonstrates the capability of the framework to capture complex spectral water quality relationships and support spatially continuous assessment. Significant seasonal differences (p < 0.001) showed higher dry season Chl-a (137.1%) and higher wet season TP (21.7%), TU (7.5%), and TN (3.9%). Long-term paired observations further indicated increases in Chl-a (73.7%), TN (30%), and TP (14.3%) from December 2016 to December 2025 (p < 0.001). Spatial hotspot analysis revealed strong clustering of TU, TN, and TP, particularly around tributary mouths and nearshore areas, highlighting priority zones for monitoring and intervention. Overall, integrating field observations, Sentinel-2 imagery, and machine learning provides an accurate, scalable, and cost-effective approach for monitoring diverse water quality parameters. The framework offers a transferable solution for strengthening freshwater monitoring in data-scarce regions and supporting sustainable management of lakes under increasing water quality pressures. Full article

High-loading plant-fiber/PLA feedstocks are often reported through final filament properties, leaving the upstream compounding mechanisms that determine pellet feedability in two-stage routes insufficiently resolved. This study developed a compatibilizer- and plasticizer-free single-screw compounding route for micronized soy hull fiber (SHF)/PLA through 42 sequential trials. Stable operation depended directly on continuous solids delivery. Reversible stop–restart observations and repeated defect patterns were consistent with a mechanism in which continuous feeding improves screw filling and solids-bed consolidation while limiting retained-air/gas carry-forward. Three-pass PLA milling reduced premix particle-scale mismatch and visible SHF/PLA agglomeration and enabled collective premix drying. The converged route used a double-mixing-zone screw, 2.75 mm die, 160/195/195/185 °C barrel profile, and 15 rev/min and produced downstream-usable pellets at 30 wt.% SHF, whereas 35 wt.% SHF defined a platform-specific processing boundary. Image analysis of 965 pellets and seven mapped pellet-to-filament lineages identified internal-texture P75 as the strongest route-level morphology marker; higher texture ranked with printing-filament readings above the 1.89 mm jamming threshold (ρ = 0.929, exact p = 0.0067). Compounded-pellet morphology therefore acts as a measurable process output linking upstream compounding history to downstream feed risk. Full article

Black soybean is a high-value alternative crop that can offset declining yellow soybean prices in Thailand. Currently, “Sukhothai3” is the only commercial variety produced through conventional breeding over the past three decades. Its low first-pod height (FPH) limits mechanized harvesting and reduces production efficiency. Recently developed elite RILs have shown improved FPH, grain yield, and protein content (34.88–41.22%), but their yield stability and adaptability across environments remain unevaluated. This information is essential for establishing an effective bi-directional seed rotation system while maintaining seed quality, quantity, and genetic purity. This study evaluated five black soybean RILs across eleven trial environments in the major production zones of Northeast Thailand, where the tropical savanna climate poses significant constraints on crop production. Field experiments used a randomized complete block design with four replications per location. Yield stability and adaptability were assessed using AMMI1 and GGE biplot analyses. BSCM41 emerged as the most stable and widely adaptable genotype, consistently outperforming the commercial check across environments and seasons. It exhibited adequate FPH for mechanized harvesting (>10 cm), rapid vegetative development, and short growth duration (88–91 days), reducing exposure to late-season heat stress and excessive rainfall. Higher seeds per pod, greater 100-seed weight, and a superior harvest index further support yield formation under marginal conditions. BSCM41 maintained high yields in both dry and rainy seasons (1524.73 and 1633.26 kg/ha, respectively), meeting the requirements for an efficient bi-directional seed rotation system. These findings can inform future breeding strategies and production management in comparable tropical environments. Full article

Extreme climatic events can alter temperatures and water availability and thereby suppress vegetation productivity. On the Huang–Huai–Hai (HHH) Plain, China’s key agricultural belt, July 2023 featured widespread heat, spatially heterogeneous drying, and limited spatial co-occurrence of heat and root zone soil drought; however, its productivity response and within-season recovery remain unclear. Here, we combine satellite-derived solar-induced chlorophyll fluorescence (SIF), MODIS gross primary productivity (GPP), environmental variables, and vegetation and elevation stratification and use extreme gradient boosting (XGBoost) with spatial block validation and SHapley Additive exPlanations (SHAP) to quantify July productivity anomalies relative to the same months during 2018–2022, identify affected pixels using a standardized SIF anomaly based on the same reference period (z_i ≤ −1.5), track recovery from August to October, and evaluate environmental associations with SIF. In July 2023, 59.6% of vegetated area exceeded its local July 90th-percentile temperature. Area-weighted anomalies were −0.0129 W m⁻² μm⁻¹ sr⁻¹ for SIF, −0.4853 g C m⁻² d⁻¹ for GPP, and −0.0147 m³ m⁻³ for root zone soil moisture (SMrz). Negative anomalies occurred in 57.3% of vegetated pixels for SIF and 73.4% for GPP. Among deciduous broadleaf forest (DBF), grasslands (GRA), and croplands (CRO), GRA had the largest mean SIF loss, whereas CRO had the smallest despite widespread local declines. Losses above 1000 m exceeded those at 0–500 m. Of 2833 affected pixels, 85.6% returned to non-negative SIF anomalies by October, while recovery above 1000 m was 75.6%. Within the July models, SMrz contained the largest individual predictive contribution across classes, although the combined contribution of air temperature, vapor pressure deficit, and downward shortwave radiation was comparable. In the recovery model, recovery stage, initial July loss, and radiation and atmospheric demand contained substantial predictive information. Together, the results characterize spatially uneven productivity loss and recovery and the environmental conditions associated with these differences. Full article

Extreme climate change and demographic change jointly reshape human exposure in arid and culturally diverse regions. This study examines projected changes in climate extremes and population exposure in Xinjiang, China, during 2021–2100 under the Shared Socioeconomic Pathway 5–8.5 (SSP5-8.5). An ensemble of eight models from the Coupled Model Intercomparison Project Phase 6 (CMIP6) was used to assess very wet-day precipitation (R95p), warm days (TX90p), and consecutive dry days (CDD), while gridded total-population projections were combined with provincial-level age- and education-specific demographic projections. Comparing the late-century period (2081–2100) with the early-century baseline (2021–2040), ensemble-mean R95p increases by approximately 47%, TX90p by 167%, and CDD decreases by about 9.9%. Population remains concentrated in oasis cities and piedmont zones, with urbanization increasing from 49.6% to 77.0%. Demographic restructuring substantially changes the composition of exposure: the elderly share rises from 9.3% to 39.4%, producing the fastest increase in age-specific exposure, while the highly educated population expands from 5.5% to 48.6%. The analysis identifies spatiotemporal concurrence rather than causal effects of climate on migration and should be interpreted as an exposure-oriented assessment rather than a complete vulnerability analysis. The findings demonstrate that climate adaptation in oasis-based drylands must account not only for changing hazards but also for population aging, educational transition, and urban concentration. As a multi-ethnic arid region, Xinjiang also raises policy-relevant hypotheses concerning the potential socio-cultural implications of projected demographic shifts, including for multilingual risk communication and intergenerational continuity; these implications require ethnicity-specific and community-level testing. Full article

Accurate estimation of aboveground biomass (AGB) is essential for sustainable pasture management, but remains challenging in heterogeneous mountain environments. This study evaluated a remote-sensing framework for estimating AGB across five landscape zones of the Aragats Volcanic Massif, Armenia, using PlanetScope imagery, terrain variables and machine learning. Biomass was measured in 30 plots comprising 90 nested quadrats during five field campaigns from April to July 2025. Predictor selection, algorithm comparison, preprocessing and tuning were performed within a fully nested leave-one-plot-out cross-validation framework. The model achieved an out-of-fold R² of 0.596 (RMSE = 54.0 g m⁻²; MAE = 33.1 g m⁻²) at the 20 × 20 m plot level, decreasing to 0.503 when the same predictions were evaluated against individual quadrats, which isolates the effect of field-observation support. Variance partitioning showed that weak zone-level performance arose from two distinct causes: dominant within-plot variability in the Meadow Steppe, and a strong soil background under sparse early-season cover in the Dry Steppe. Fine-resolution UAV imagery, acquired without reflectance calibration, did not improve prediction in a matched cross-sensor comparison. Applied to 18 pastures covering 1822.5 ha, the model yielded an aggregate campaign-date stock of 1651.45 t (95% uncertainty interval 1207.70–2092.80 t). Full article

To investigate the corrosion resistance and service life of water-based epoxy-coated reinforcing bars under severe environmental conditions, HRB400 ribbed reinforcing bars were used as the substrate. Four types of water-based epoxy-coated reinforcing bars were prepared, containing 0.3% graphene–polyaniline (PAG), 0.3% iron oxide, 10% zinc phosphate, and 10% zinc–iron powder, respectively, with a bare reinforcing bar control group also included. In accordance with standards such as the ‘Design Standard for Durability of Concrete Structures’, durability tests were conducted under various conditions, including long-term immersion in marine chloride solutions, wet–dry cycling, de-icing salt freeze–thaw cycles, baking and immersion in saline soil, and concrete mixed with seawater. Corrosion current density (I_corr) was monitored using a three-electrode system and the linear polarisation method, and service life was predicted based on the Wiener process. The results indicate that, under all severe environmental conditions, the corrosion current density of the coated reinforcing bars was significantly lower than that of the bare reinforcing bars (BRBs). After 70 cycles of marine wet–dry cycling, the corrosion current density of the bare reinforcing bars reached 0.4569 μA·cm⁻², whilst that of the 0.3% PAG coating was 0.1103 μA·cm⁻², substantially lower than that of the bare bars (0.4569 μA·cm⁻²); after 110 freeze–thaw cycles in a de-icing salt environment, the corrosion current density of the bare reinforcing bars was 0.4480 μA·cm⁻², whilst that of the PAG-coated bars was 0.1003 μA·cm⁻². After 80 cycles of baking and immersion in a saline soil environment, the corrosion current density of the graphene–polyaniline-coated steel increased from 4.97 × 10⁻³ μA·cm⁻² to 0.1021 μA·cm⁻² (approximately a 20-fold increase), whilst that of the bare steel rose to 0.4489 μA·cm⁻². In concrete mixed with seawater, the corrosion current density of bare reinforcing bars reached as high as 8.60 μA·cm⁻² after 120 days, whereas that of coated reinforcing bars was 0.24 μA·cm⁻², markedly lower than 8.60 μA·cm⁻² for the bare bars. Lifespan predictions indicate that, provided that the specifications for concrete strength and protective layer thickness are met, water-based epoxy coatings have the potential to delay the onset of severe corrosion (I_corr ≥ 1 μA·cm⁻²) beyond the 50-year design threshold in seawater wet–dry cycling zones and saline soil environments, and are projected to meet the 100-year design requirements in de-icing salt environments. It should be noted that these projections are based on accelerated tests and require validation through long-term field performance data. Graphene-containing polyaniline nanocomposite coatings exhibited the best overall protective performance, whilst zinc phosphate coatings demonstrated outstanding stability in high-chloride environments. For the specific formulations tested in this study, the enhanced corrosion resistance is attributed to the synergistic combination of the epoxy matrix, inorganic fillers (TiO₂ and BaSO₄) and functional additives; these components collectively provide physical shielding, chemical passivation and dynamic pore-blocking effects. Within the scope of this study, the nanocomposite coating containing 0.3 per cent PAG exhibited the best overall protective performance. Full article

The economically important species Phyllanthus emblica L. has received increasing attention, yet its climate-driven distributional shifts across China remain unexplored. Using 446 occurrence records and a parameter-optimized MaxEnt model (RM = 0.1, FC = LQ), we forecasted habitat changes under three SSP scenarios (126, 370, 585) across the 2050s, 2070s, and 2090s. Three temperature variables, namely temperature seasonality (Bio4), temperature annual range (Bio7), and mean temperature of the driest quarter (Bio9), collectively contributed 90.2% to the model, confirming that thermal conditions, particularly during dry seasons, dominate habitat suitability. Current suitable habitat covers 86.43 × 10⁴ km², largely confined to South China’s tropical and southern subtropical belts. Future projections indicate non-linear range responses, with a general northwestward centroid shift, although intermediate periods exhibit oscillatory northeastward and southwestward fluctuations. Under the high-emission SSP585 scenario, modest expansion occurs in high-elevation areas of southeastern Tibet, while contraction affects less than 1% of current suitable low-elevation zones. Based on these findings, we recommend designating long-term core conservation areas (southern Yunnan, southern Guangxi, and Hainan), conducting adaptive introduction trials in expansion zones (e.g., Panzhihua, Sichuan), and implementing planting controls in contraction zones (e.g., northern Guizhou). These insights provide a scientific basis for climate-adaptive management of P. emblica in China. Full article

Rising antimicrobial resistance and healthcare-associated infections have intensified the demand for antibacterial medical textiles that avoid metal-based or synthetic biocides. The present study is about an entirely plant-derived antibacterial and antioxidant finish for cotton fabric, using Fagonia arabica extract and clove oil as bioactive agents and tragacanth gum as natural polymeric binder. These bioactive loadings were applied via pad-dry-cure at varying percentages (1–5%). FTIR spectroscopy verified the successful bioactive deposition, while polarized optical microscopy showed that the structure of the fibers changed as a function of the amount of extract used, with Fagonia arabica extract causing swelling of the fibers and clove oil forming a coalescing surface film to provide complete web-like fiber coverage at the highest loading. Essential comfort characteristics were maintained together with functionalization, as all treated samples showed hydrophilic wettability with absorption times ranging from 1.8 to 7.5 s depending on different formulations. The Fagonia arabica–clove oil formulation (5% each) demonstrated the best antibacterial activity (in terms of zone of inhibition) and antioxidant activity radical-scavenging capacity using ABTS radical assay as compared to the clove-oil-only and Fagonia-only formulations. Beyond their antibacterial and antioxidant activities, the formulation of Fagonia arabica–clove oil proved to be effective (more than 69%) in all concentrations in repelling mosquitoes, indicating an additional protective function that is useful in environments where insects transmit infections. These results prove the feasibility of a completely natural bioactive-and-binder strategy that can provide relevant antibacterial, antioxidant, and mosquito repellency activity without sacrificing comfort, providing a scalable and sustainable paradigm for antimicrobial, antioxidant, and mosquito-repellent medical textiles. Full article

Rising global demand for space cooling is driving peak electricity loads, greenhouse gas emissions, and refrigerant pollution from vapor compression air conditioning. Evaporative cooling is a proven, low-electricity alternative using no synthetic refrigerants, but its evidence base is fragmented and its regulation underdeveloped. This review synthesizes sixteen publicly available institutional publications from 2009 to 2024, analyzing performance, barriers, and deployment conditions. Multistage indirect evaporative cooling achieved reported or simulated energy reductions of 57–95% against study-specific vapor compression baselines in hot–dry climates, with Energy Efficiency Ratio values of 63–76 versus a rooftop unit baseline of 12. These figures rest almost entirely on monitoring in one ASHRAE climate zone, with several compared against modeled rather than measured baselines. Two independent reviews published twelve years apart each identify Iran as the only country with mandatory energy performance requirements for evaporative coolers; water use labeling remained similarly underdeveloped. The evidence base is asymmetric: the United States provides the most rigorous monitoring, while India’s larger deployment, exceeding 800 buildings, lacks equivalent verification. Five research gaps are identified, most urgently the absence of integrated water–energy life-cycle accounting. A four-part policy response is proposed: climate suitability mapping, mandatory performance and water use standards, open monitoring for publicly funded pilots, and prioritization of data centers for market development. The regulatory gap identified here also holds in the European Union, where the Ecodesign framework addresses vapor compression air conditioners but does not constitute standalone evaporative air coolers as a regulated product group. Full article

Background/Objectives: The purpose of this study was to evaluate associations between quantitative ellipsoid zone (EZ) integrity metrics derived from spectral-domain OCT (SD-OCT) and visual outcomes, including clinically meaningful visual acuity (VA) loss, in dry age-related macular degeneration (AMD). Methods: This single-center retrospective image-analysis cohort included 351 eyes from 351 patients with intermediate AMD or atrophic changes. Macular SD-OCT scans were analyzed using a certified-reader-validated machine learning-based segmentation platform to delineate the EZ, retinal pigment epithelium (RPE), and Bruch’s membrane (BM). EZ metrics included EZ-RPE thickness (i.e., outer segment thickness) and EZ attenuation, defined as partial attenuation (EZ-RPE thickness of ≤20 µm, abnormal outer segment thinning)) or total attenuation/loss (0 µm). Drusen volume was quantified from the RPE-BM compartment. VA was converted to ETDRS letters. Associations between baseline OCT metrics and baseline VA, Year 2 VA, and ≥15-letter VA loss were assessed using nonparametric testing, linear regression, and ANCOVA. Results: Greater EZ-RPE thickness and lower EZ attenuation were associated with better baseline VA (all p < 0.001), and EZ metrics remained significant in cross-sectional regression models. Among 188 eyes with Year 2 follow-up, 38 (20%) experienced ≥15-letter VA loss. These eyes had significantly lower baseline EZ-RPE thickness (i.e., abnormal outer segment thinning) and greater EZ attenuation than eyes without such loss (all p < 0.001). In ANCOVA models, EZ metrics remained associated with Year 2 VA (all p < 0.001), whereas drusen volume was not. Conclusions: Quantitative EZ integrity metrics were associated with cross-sectional and longitudinal visual outcomes in dry AMD. EZ-RPE thickness and EZ attenuation may serve as clinically relevant OCT biomarkers reflecting photoreceptor integrity and risk of meaningful VA loss. Full article

The development of new principles for controlling the technical systems requires the use of reliable actuators. A sliding steel/steel contact under a high-density electric current could serve as one of their elements. The search for the factors reducing the wear of the contacts is a subject of scientific and commercial interest. One such factor is the melting that occurs within a sliding steel/steel electrical contact space. The overall goal of this study is to describe the characteristics of an M2 steel/steel sliding electrical contact during the formation of a melt-like state in the contact zone. Dry sliding of M2 steel (sample) against C45 steel (counterbody) under an alternating electric current at a density higher than 100 A/cm² is performed as a model experiment using the well-known “pin-on-ring” tribo-loading configuration. The formation of tribolayers on the sample and the counterbody is demonstrated using a scanning electron microscope and a MICRO MEASURE 3D-station non-contact device. According to the EDX analysis, the contact layers predominantly contain oxygen and iron. Two sectors with different morphological features are observed on the M2 steel sliding surface. A melt-like state is visible in one of the sectors. This state is assumed to form within a certain sublayer. A method for calculating this sublayer thickness is proposed. This thickness does not exceed 10 μm. The calculation model has revealed that the thickness of this sublayer depends mainly on the external impact power rather than on the atomic and phase composition of the tribolayer. An increase in the contact current density is consistent with an increase in the calculated thickness of this sublayer, an increase in the electrical conductivity of the contact, and a decrease in the coefficient of friction (COF). The proposed analysis of the obtained results could serve as a basis for broader generalizations. Full article

Forced spray on transmission gears performs the triple functions of lubrication, heat dissipation, and tooth surface cleaning under high-speed and heavy-duty conditions, serving as a key technical means to prevent scuffing, pitting, or even tooth breakage failure and ensure highly reliable operation of the transmission system. This study conducted numerical simulations using CFD to investigate the lubrication performance of high-speed spur gear pairs with respect to nozzle parameters including jet velocity, nozzle position, included angle, length, and number of nozzles. The results show that the medium jet velocity of 40–60 m/s achieves an optimal balance between penetration depth and spray dispersion. The results indicate that a medium jet velocity of 40–60 m/s optimally balances penetration depth and spray dispersion. Dual-nozzle oil injection significantly improves spatial uniformity and establishes a stable circular recirculation structure, increasing the oil volume fraction in the meshing zone by approximately 40% compared to the single-nozzle configuration, and reducing the area of dry patches by over 60%. A nozzle inclination angle of 60–90° combined with a length of 30 mm yields the best combination of oil delivery and coverage. Furthermore, upgrading from a 2 + 1 to a 3 + 1 nozzle layout enhances oil film continuity and suppresses abrupt negative-pressure fluctuations during meshing, thereby stabilizing the hydrodynamic lubrication effect. These findings provide quantitative guidance for optimizing nozzle geometry and layout in high-speed gearbox lubrication systems, contributing to improved reliability and reduced energy loss. Full article

This study proposes a new method for the topological synthesis of principal component projections and hydrogeochemical stoichiometric equality lines on self-organizing map (SOM) component planes to assess groundwater chemistry forming factors and quality in the Pleistocene unconfined aquifer of the Southern Bug and Sinyukha interfluve area, Ukraine. The hydrogeochemical characteristics clustered by the SOM were further examined using the graphical cross-validation method. The groundwater dataset used in the analysis consisted of 10 parameters (i.e., pH, total dissolved solids, $\mathrm{C}{\mathrm{a}}^{2+}$, $\mathrm{M}{\mathrm{g}}^{2+}$, $\mathrm{N}{\mathrm{a}}^{+}$, ${\mathrm{K}}^{+}$, $\mathrm{H}\mathrm{C}{\mathrm{O}}_3^{-}$, $\mathrm{C}{\mathrm{l}}^{-}$, $\mathrm{S}{\mathrm{O}}_4^{2-}$, and $\mathrm{N}{\mathrm{O}}_3^{-}$) from 91 samples collected during the dry season. Subsequently, for SOM construction, we utilized six log-ratio relationships of milliequivalent ion concentrations. Based on the results, the hydrogeochemical groundwater data were classified into three clusters, which revealed three water types and processes controlling their chemistry: salinity driven by sulfate inputs (Cluster 1), highly salinity driven by nitrate-chloride and sulfate pollution (Cluster 2), and relatively fresh water governed by natural carbonate dissolution and silicate weathering (Cluster 3). The salinity types were identifiable in the northern part of the study area, characterized as the primary zone of initial intense pollution. High salinity types were identified in the eastern and southeastern parts of the territory (with delayed water exchange), whereas relatively fresh types were identified in the central part (with active water exchange) as well as in the western and southwestern parts. Modeling confirmed that extensive sulfate, nitrate, and chloride contamination led to anthropogenic degradation of the aquifer system. Full article

Theileria orientalis and Babesia bigemina are hemoprotozoan parasites that adversely affect domestic cattle (Bos taurus) productivity and health worldwide. Rapid climatic changes in different geo-climatic zones observed over the past few years may have altered the distribution and transmission of tick-borne pathogens and vectors. Though these parasites are reported in Sri Lanka in surveillance records, there is a limited understanding of their current distribution pattern. The present study aimed to determine the prevalence and genetic characterization of B. bigemina and T. orientalis in cattle from three geo-climatic zones of Sri Lanka during the period from January 2025 to March 2026. Out of 384 samples collected from animals (wet, n = 124; dry, n = 208; and intermediate, n = 52 zones) in Sri Lanka, the overall prevalence of 60.2% for T. orientalis and 7.6% for B. bigemina was revealed using PCR-based detection methods. The highest prevalence of T. orientalis was observed in the wet zone (86.3%), while the highest prevalence of B. bigemina was 17.3% in the intermediate zone. Co-infections were detected in 5.7% of cattle across all three zones. These results indicate the dominance of T. orientalis compared with B. bigemina in cattle in Sri Lanka. The observation of co-infections highlights the importance of vector control against vector-borne diseases in Sri Lanka. Full article