Search Results (2,205)

In the context of climate change and increased frequency of droughts, summer supplementation of grazing cattle may improve productivity and resilience of pastoral systems. However, the provision of supplements may increase the risk of heat stress in cattle. This study aimed to evaluate the productive and physiological response of grazing steers supplemented during summer. Three independent studies were conducted over three summers (2020–2023). In each experiment, steers grazing native grasslands with access to shade were allotted to one of two treatments: control (CONT) and supplementation (SUPPL), in a completely randomized block design. SUPPL steers were group-fed in the morning three days per week with an energy–protein ration at a level of 1.98% body weight (BW) on days of feeding. Pasture attributes, animal performance, respiration rate (RR), and body temperature (BT) were analyzed using a mixed model. According to the temperature–humidity index, cattle were exposed to heat stress 32% of the time. Summer supplementation increased average daily gain and final body weight of steers. Although supplementation temporarily increased BT (morning) and RR (afternoon), daily average RR and BT were similar for both treatments. These findings show that summer supplementation improves animal performance of grazing steers without increased risk of severe heat stress. These results are aligned with the concept of sustainable livestock intensification, which aims to enhance animal source foods to feed a growing population without causing collateral animal welfare issues. Full article

We have used long observations of galaxy clusters obtained with the Rossi X-ray Timing Explorer to search for the 3.55 keV line from sterile neutrino decay. If a lepton-number asymmetry exists in one or more types of active neutrinos in the early Universe, sterile neutrinos can be produced via the Shi–Fuller mechanism. The data consist of 11 clusters observed for a total of 3.1 megaseconds using the Proportional Counter Array. A 2.5$\sigma$ excess of emission over a thermal model is found over the energy span of the 3.55 keV line in the combined spectra of the eight clusters that individually have an excess. These residuals are added to increase the signal to noise ratio of the excess, which is then modeled with a Gaussian to simulate the instrumental spectral response. We find a significant correlation (r = 0.76) for a line centered at 3.6 keV with a model flux of 3.07 × 10⁻⁵ ph cm⁻² s⁻¹. Mixing angle for detected clusters ranges from 2.0 to 21.6 × 10⁻¹⁰. The decay rate inferred from the line flux is strongly correlated (r = 0.87) with cluster temperature, which is due to hotter, more massive clusters having a larger amount of dark matter. Approximately half of the total flux comes from the Coma cluster. The mixing angle for Coma is calculated to be 6.2 × 10⁻¹⁰. We fit the Coma cluster spectrum with two different three-component models. The first includes a Gaussian fixed at 3.55 keV to model soft emission. The flux of the Gaussian is 5.6 × 10⁻¹² ph cm⁻² s⁻¹ or 1.3% of the total flux. The second three-component model uses a second thermal component to model soft emission. This model gives a temperature of 0–17 keV for the second thermal component and a lower temperature for the hot component. This indicates that the second thermal component is modeling high-energy residuals rather than low ones, where the Gaussian is. Though our line fluxes exceed most reported detections and upper limits, they do not overproduce the dark matter. We conclude that some fraction of the marginally detected excess could be attributed to the decay line since low-temperature thermal emission and systematics fail to model it completely. Full article

This study assessed the effects of eco-efficient aquafeed formulations on the growth, body composition, nutrient retention, and flesh quality of rainbow trout (Oncorhynchus mykiss). Four extruded diets were tested: a conventional control (Ctrl) and three eco-efficient formulations (No-PAP, PAP, and Mix) combining single-cell ingredients, insect meal, selected plant proteins, and aquaculture by-products, with long-chain omega-3 fatty acids (DHA and EPA) supplied primarily from microalgae. Rather than isolating single-ingredient replacements, the objective was to evaluate the efficacy of complex, industry-feasible formulations designed for practical application. These experimental feeds were administered to 800 trout (initial body weight 63 g), distributed across four replicates per diet. After a 97-day trial, results showed no significant differences in growth performance (final weight, weight gain, and relative growth rate) between diets. Feed conversion ratios (~0.78) were within expected ranges for rainbow trout under these conditions. Fillet texture and composition were similar across all groups; however, trout fed the No-PAP diet developed a significantly more yellow tint in fillet color, likely attributed to xanthophyll pigments from plant- and algae-based ingredients. The environmental impact of the diets was driven by specific ingredient choices, as evidenced by a carbon footprint analysis ranging from 1.39 kg CO₂ eq. (PAP diet) to 2.36 kg CO₂ eq. (Ctrl diet). These findings demonstrate that the three alternative formulations matched the efficacy of conventional feed, offering a sustainable option for trout aquafeed production. Full article

The widespread presence of antibiotic residues in aquatic environments poses severe ecological risks. While photocatalytic oxidation offers a promising, eco-friendly remediation technology, developing stable and high-efficiency photocatalysts remains a significant challenge. This study investigates the synthesis of Bi₂O₃/TiO₂ heterojunction with tailored morphological structures to enhance the degradation of tetracycline (TC). A series of Bi₂O₃/TiO₂ photocatalysts were prepared via a solvothermal method using mixed alcohol solvents (ethylene glycol and ethanol) to regulate morphology. Comprehensive characterization was performed using XRD, BET, TEM, XPS, UV-Vis, and PL spectroscopy. Photocatalytic activity was evaluated by monitoring TC removal efficiency under light irradiation. The optimized catalyst of BT5-EG3 (n(Bi)/n(Ti) = 0.05; V(EG):V(ethanol) = 1:3) achieved the highest TC conversion of 93.9% within 120 min. This superior performance is attributed to a large specific surface area, abundant lattice oxygen, and a narrowed band gap of 2.52 eV, which significantly promoted the spatial separation of photogenerated charge carriers and suppressed their ultrafast recombination. The reaction followed pseudo-first-order kinetics, and the catalyst demonstrated excellent stability, providing a robust strategy for treating antibiotic-polluted water. Full article

Hourly concentrations of PM_2.5-bound elements were continuously monitored in Windsor, Canada, from April 2021 to April 2023. Health risk assessment methods of the USEPA were utilized to quantify lifetime cumulative cancer risks (CRs) using six PM_2.5-bound elements, and chronic non-cancer hazard quotients (HQs) using 11 elements, for each season, each source factor, and each hour of day. The two-year average PM_2.5 mass concentration was 9.2 μg/m³, slightly exceeding Ontario’s Ambient Air Quality Criteria of 8.8 μg/m³. A discernible diurnal concentration pattern was noted for most elements, peaking during morning rush hours and tapering during the daytime, largely attributed to local human activities and changes in atmospheric mixing heights. Despite this, both the total lifetime cumulative CR (4.1 × 10⁻⁵) and non-cancer total HQ (0.82) from exposure to ambient elements remained below the corresponding USEPA-acceptable levels. The seasonal variation in CRs and HQs was minimal. However, the diurnal variation was strong, with higher risks during morning rush hours (6:00–8:00) when traffic volume peaks, and lower risks during the daytime (12:00–20:00) when atmospheric mixing height is enhanced. Metal processing emerged as the most significant contributor to the total CR (52%) and HQ (60%), followed by coal/heavy oil burning (19% and 16%, respectively), and vehicular exhaust (19% and 12%, respectively). The remaining two source factors accounted for 10% of CR and 12% of HQ. Cd (62%) was the largest contributor to CRs, followed by Cr(VI) (25%), Co (6%), As (5%), Ni (2%), and Pb (<0.1%). Similarly, Cd dominated HQs (73%), followed by Mn (11%), Ni (6.3%), with the remaining eight elements collectively contributing 9.7%. Although levels of CRs and HQs are low, efforts to mitigate ambient Cd emissions from metal processing sources will help reduce exposure and protect the environment and human health, given Cd is the primary contributor to the total CR and HQ during the study period. Full article

As widely adopted privacy models in privacy-preserving data publishing (PPDP), k-anonymity and ℓ-diversity have been extensively studied by researchers to enable the release of useful information while preserving data privacy. However, existing methods suffer from several limitations. They often rely on single-dimensional privacy models and lack unified metrics for accurately quantifying privacy leakages. Many approaches overlook the impact of semantic similarity and adversarial prior and posterior beliefs among sensitive attributes and frequently employ suboptimal similarity measures that fail to account for the heterogeneous nature of quasi-identifiers, thereby degrading both privacy protection and data utility. To address these challenges, this paper proposes CAMDP, a unified clustering-based anonymization method for privacy-preserving data publishing with multidimensional privacy quantification. CAMDP constructs equivalence classes that satisfy k-anonymity while simultaneously enhancing sensitive attribute diversity, reducing semantic similarity, and limiting divergence between prior and posterior adversarial beliefs. A unified multidimensional metric is introduced to jointly quantify privacy leakage and information loss, guiding the anonymization process. Additionally, a similarity-aware distance metric tailored to mixed-type quasi-identifiers is employed to reduce information loss. Experimental results on three benchmark datasets, Adult, Careplans, and Airline, demonstrate that CAMDP consistently outperforms state-of-the-art methods. Across all tested configurations, CAMDP achieves the lowest average privacy leakage (0.1235, 0.0795, and 0.1855, respectively), lower average information loss (0.626, 0.636, and 0.60, respectively), and the lowest average intra-cluster dissimilarity (0.586, 0.635, and 0.573, respectively), while maintaining competitive execution time across the three datasets. Full article

The transition from pure to mixed-species forest stands is increasingly promoted to enhance ecosystem stability and multifunctionality. The growth conditions may influence the physical and mechanical properties of wood. This study evaluated wood density in pure and mixed stands of silver birch, Norway spruce, and Scots pine in Lithuania and analyzed its relationships with tree allometric parameters. Nine study plots representing pure (100%) and mixed (70/30%) stands were established under comparable site conditions. Wood density at breast height was assessed using resistance drilling (IML Resi PD500), and the increment core samples were analyzed with the LIGNOSTATION™ system. The mean values of wood density for silver birch differed by 11%, depending on the wood density determination method used. Differences between pure and mixed stands were insignificant and generally did not exceed 6%–10%. No consistent trend that was attributable to species mixing was identified. The combined data from pure and mixed stands indicate that the mean wood density, converted from microdrilling measurements, was highest in silver birch (546 kg m⁻³ ± 1.87 kg m⁻³), followed by Scots pine (476 kg m⁻³ ± 1.85 kg m⁻³) and Norway spruce (437 kg m⁻³ ± 1.66 kg m⁻³). Resistance drilling showed a moderate relationship with the core samples’ wood density (R² = 0.59), supporting its suitability as a semi-nondestructive method. Diameter at breast height was the only tree parameter that was consistently significant across all predictive models. The combined model for all species explained up to 43% of wood density variation, while species-specific models had lower explanatory power. Overall, the results indicate that species mixing has a limited effect on wood density under the studied conditions and is unlikely to substantially alter wood quality in terms of wood density. Full article

Rising temperatures and droughts are triggering forest die-off in climate warming hotspots such as the Mediterranean Basin. UAVs equipped with LiDAR and multispectral sensors offer a powerful tool for surveys of tree vigor at landscape level. We used UAV-acquired LiDAR data and multispectral camera imagery to segment individual tree crowns, classify species, and assess the health status in two drought-affected forests in northeastern Spain: a mixed Pinus pinaster–Quercus ilex forest and a Pinus halepensis forest. Individual trees were segmented and classified using object-based image analysis with the Random Forest algorithm incorporating spectral, structural, and topographic variables. Greenness indices (NDVI and EVI) were analyzed in relation to crown height, topography (slope and elevation) and solar radiation, and their interactions. Analyses showed satisfactory crown segmentation (F-Score = 0.85–0.86) and species classification (Overall accuracy = 0.86–0.99), though distinguishing spectrally similar classes remained challenging. Taller P. pinaster trees exhibited higher NDVI, while taller P. halepensis displayed higher NDVI values in dense neighborhoods and on gentle slopes. These findings highlight the potential of high-resolution UAV-based remote sensing for effective near-real-time detection and attribution of forest die-off. Future research should aim to improve algorithm accuracy and better integrate field-based validation across different forest types. Full article

Friction stir-welding (FSW) is widely recognized as a modern solid-state technology used to join dissimilar materials by solid-state mechanical mixing. Such mechanical mixing can be exploited to fabricate in situ composite structures through solid-state deformation mechanisms. The present investigation highlights the microstructural evolution and mechanical properties of an in situ composite structure fabricated by FSW of aluminum (Al) to titanium (Ti) incorporating a thin Nickel (Ni) interlayer. A 0.1 mm thick Ni foil was placed across the full butt interface between 4 mm thick Al and Ti plates before friction stir-welding. Properties of the composite were investigated in detail, and the results revealed that fragmented Ti and Ni particles of different sizes were consolidated in the weld nugget. Al, on the other hand, exhibited substantial microstructural refinement and developed an equiaxed microstructure with random grain orientation, mixed grain boundaries and low micro-strain accumulation in the weld nugget. At the processing temperature, Al reacted with both Ti and Ni to form multiple intermetallic compounds. Tensile testing indicated that the tensile properties of the weld were close to those of the base aluminum. This retention of mechanical properties in spite of recrystallization is attributed to the following mechanisms: (1) Ti and Ni undergo severe deformation, forming fine particles with varying sizes and shapes; (2) at particle interfaces, diffusion and chemical reactions produce interlayers and intermetallic compounds; (3) these particles are consolidated within dynamically recrystallized Al, imparting composite characteristics to the weld nugget; and (4) the particles containing intermetallic compounds act as dispersoids in the Al matrix. Quantitatively, the weld retained 98% (104.2 ± 3.3 MPa) UTS and 90% (17.1 ± 1.2) ductility of base aluminum, demonstrating the effectiveness of the Ni interlayer approach in controlling brittle intermetallic formation. Full article

Bacteria-based self-healing concrete is extensively shown to improve strength and durability; yet, the mechanistic relationship among microbial activity, damage progression, and transport resistance is still ambiguous. This study examines the interrelated mechanical and transport properties of concrete that incorporates Bacillus subtilis by directly substituting mixing water. Concrete mixtures with 0%, 5%, and 10% bacterial solution were assessed for compressive strength, complete stress–strain response, split tensile strength, flexural toughness, fast chloride ion penetration, and capillary sorptivity. X-ray diffraction was employed for microstructural validation. Results indicate a dose-dependent shift from brittle to quasi-ductile behavior, marked by augmented strain capacity, postponed crack localization, and improved post-cracking energy absorption. The mechanical alterations resulted in substantial decreases in chloride ion penetrability (up to 57%) and capillary sorptivity (up to 60%), signifying a drop in crack-assisted transport. X-ray diffraction verified the production of calcite resulting from microbial-induced calcium carbonate precipitation. The results indicate that the improvement in durability of bacterial concrete is attributable not only to pore filling but also to altered damage mechanisms that diminish the connectedness of transport channels, underscoring the potential of Bacillus subtilis as a bio-admixture for resilient structural concrete. Full article

The endemic Minuartia nifensis, the only known gynodioecious species of its genus, offers a suitable model for understanding the relationships between floral characteristics, pollination, and mating systems in species with narrow distributions and single populations. We analyzed population structure, floral morphology, pollen viability, stigma receptivity, mating system components, and pollinator assemblages using field observations, morphometric measurements, controlled pollination experiments (autogamy, allogamy, apomixis and open pollination), and standardized pollinator surveys. The population exhibited an approximately balanced hermaphrodite–female ratio (0.97:1) and clear sexual dimorphism, with hermaphrodite flowers significantly larger than female flowers. Despite this dimorphism, pollinator visitation was similar between morphs, with 52.54% of visits to hermaphrodite flowers and 47.46% to female flowers. A total of 1734 visits by seven visitor species were recorded, of which approximately 95% of potentially effective pollen transfer was attributable to three bee taxa. Pollen viability, stigma receptivity, and visitation frequency peaked between 12:00 and 14:00, accounting for 58% of total insect visits. Controlled pollination experiments showed highest reproductive success under cross-pollination and limited success under self-pollination, indicating a mixed but predominantly outcrossing mating system. Together, these results suggest that gynodioecy in M. nifensis may be supported by floral differentiation, temporal reproductive traits, and pollinator-mediated pollen transfer. Full article

The strong adhesion between cathode materials and aluminium (Al) foil substrates presents a significant challenge in the recycling of spent lithium-ion batteries (LiBs). Conventionally, high temperatures and high concentrations of costly organic solvents such as N-methyl-2-pyrrolidone (NMP), dimethylacetamide (DMAC), dimethylformamide (DMF), and dimethyl sulfoxide (DMSO) are used to enhance ultrasonication-based delamination. In this study, a novel, eco-efficient approach was demonstrated for delaminating cathode materials from Al foil using a low-concentration organic citric-acid-assisted low-power ultrasonic treatment coupled with a gentle, low-power-per-volume mechanical mixing system at room temperature. The separation mechanism was attributed to the structure disruption, possibly swelling, of the polyvinylidene fluoride (PVDF) binder using low-concentration citric acid and the cavitation effects induced by ultrasound. Key parameters influencing the delamination efficiency included the solvent type, temperature, ultrasonic power, and treatment duration. Under optimised conditions, citric acid was used as the sonication reagent, with a process temperature of 20 °C, 60 W ultrasonic power, and 80 min of ultrasonication; a delamination efficiency of approximately 92% was achieved. The recovered cathode materials exhibited low agglomeration, favouring subsequent leaching processes. This work proposes an environmentally friendly and effective method for cathode and Al foil recovery from spent LiBs, integrating manual dismantling, ultrasonic treatment, and material separation. Full article

Ti₃C₂T_x/Al6061 composites were fabricated via vacuum induction melting, with systematic analysis conducted on their microstructure, mechanical properties, and wear behavior. Findings indicate that Ti₃C₂T_x addition significantly refined the composite grain size. Uniformly dispersed Ti₃C₂T_x particles promoted heterogeneous nucleation, reducing the average grain size by 44.7% compared to the matrix at the optimal 2 wt.% addition. Strong interfacial bonding ensured efficient load transfer, resulting in a 48.4% increase in tensile strength for the 2 wt.% Ti₃C₂T_x/Al6061 composites compared to the matrix alloy, while elongation decreased by 11.7%. Tribological analysis revealed that the wear rate of 2 wt.% Ti₃C₂T_x/Al6061 composites increases with applied load but remained substantially lower than Al6061 under all tested conditions. This excellent wear resistance is attributed to the synergistic effect of the protective mechanically mixed-layers formation and the inherent self-lubrication property of Ti₃C₂T_x during sliding contact. With increasing load, the friction coefficient and tendency for microcracking on the worn surface of the composite increased, and the dominant wear mechanisms transitioned from abrasive and adhesive wear to delamination wear. Full article

High-dimensional mixed data often lack a unified semantic representation for continuous and discrete attributes, which hinders mixed-attribute similarity modeling and can result in unstable reducts and overfitting in existing neighborhood rough set (NRS) methods. To address this issue, we propose IF-EMD-SPA, an attribute reduction method for NRS grounded in Information Flow theory. Unlike conventional NRS methods that rely on discretization or a single reduction criterion, IF-EMD-SPA first establishes a unified representation framework for heterogeneous attributes based on classifications and an Information Channel Core. It then integrates Earth Mover’s Distance (EMD) and Set Pair Analysis (SPA) to define a similarity metric for mixed attributes. In addition, a three-stage greedy reduction strategy is designed under the dual constraints of dependency preservation and structural error, consisting of dependency-driven forward selection, similarity-driven structure completion, and backward redundancy removal. Experiments on five UCI benchmark datasets and two high-dimensional gene expression datasets show that IF-EMD-SPA achieves average accuracies of 93.5% (k-Nearest Neighbors, KNN), 93.9% (Support Vector Machine, SVM), and 90.8% (Classification and Regression Trees, CART), with SVM achieving the best results on all seven datasets. Under CART, it reaches 100% accuracy on Wine and WPBC, improving performance by up to 37.5 percentage points over comparison methods. Full article

The milpa (a traditional Mesoamerican agricultural system) constitutes a dynamic space with a great diversity of agro-food and sociocultural resources. The objective of this study was to evaluate the milpa’s contribution to food self-sufficiency and to document perceptions of its attributes and cultural significance in San Felipe Tejalápam, Oaxaca. Using a mixed-methods design that included food frequency questionnaires, 24 h dietary recalls (n = 50), and semi-structured interviews (n = 12), the percentage of adequacy (PA) and the symbolic perception of the milpa were analyzed. The results indicate that milpa foods are important for local nutrition, providing significantly higher percentages of adequacy (p ≤ 0.05) for carbohydrates (63.72%), fiber (69.72%), and iron (77.22%). However, the system proved insufficient in energy (42.35%), protein (32.38%), vitamin C (2.69%), vitamin E (0.17%), and potassium (11.14%) compared to external food sources. From a cultural perspective, the milpa was identified as a pillar of community identity. Participants highlighted its culinary properties, health benefits, and its role as a driver of economic and food self-sufficiency. It is concluded that the milpa not only satisfies key nutritional needs but also preserves ancestral knowledge and strengthens the social fabric of the population. Full article