Search Results (9,687)

Composites were obtained by using a commercial bicomponent epoxy resin (containing Al₂O₃ and SiO₂) and cubic BN (cBN) (0–50 wt.%). Two preparation methods were used: (a) the cBN powder was first mixed with the resin base and further with the hardener, and (b) the cBN powder was first mixed with hardener and afterwards with the resin base. Both methods show a similar enhancement trend in the thermal conductivity from 0.77 W/mK in the resin without additive to 1 and 1.5 W/mK in the ones filled with 30 and 50 wt.% cBN, respectively. A reasonable decrease in bending strength from 74 for 0 wt.% cBN to 70 or 64 MPa for 30 wt.% cBN added by method (a) or (b), respectively, occurs. The bending strain at breakage decreased from 5.58% to 2.65 or 3.78%. High sensitivity vs. processing was also found for electrical properties measured for frequencies of 1–10⁷ Hz. An increasing amount of cBN decreased the room temperature conductivity, dielectric constant, and dielectric loss tangent and modified the shape of the curves vs. frequency. However, in samples with 30 wt.% or more of cBN, a partial recovery to a high insulating state was observed. Full article

The Altyn Tagh Fault plays a critical role in understanding the tectonic evolution of the northern margin of the Tibetan Plateau. However, considerable debate persists regarding its activity and deformation history. This study investigates volcanic rocks from the Beidayao-Jianquanzi-Hanxia-Hongliuxia area in the eastern segment of the fault. By employing zircon U-Pb dating, whole-rock geochemistry, and Sr-Nd isotope analysis, we aim to elucidate their petrogenesis and tectonic setting, thereby providing new insights into the crustal evolution of the eastern Altyn Tagh Fault. Zircon U-Pb dating of the Hongliuxia rhyolite yields a weighted mean ²⁰⁶Pb/²³⁸U age of 106.6 ± 0.6 Ma, indicating an Early Cretaceous eruption. Geochemically, the western part of the study area (Beidayao and Jianquanzi) is dominated by basalts that exhibit significant enrichment in large ion lithophile elements and light rare earth elements, together with high Nb concentrations (>20 ppm), as well as high Nb/La (0.64–1.12) and Nb/U (29.8–35.42) ratios, consistent with the characteristics of high-Nb basalt. In contrast, the eastern area (Hanxia and Hongliuxia) is characterized by andesitic rocks that display typical continental arc affinities, marked by enrichment in Th, U, and Pb and depletion in Nb, Ta, and Ti. Isotopically, the basalts show initial ⁸⁷Sr/⁸⁶Sr ratios of 0.706–0.707 and ε_Nd (t) values ranging from −3.2 to 0.8, whereas the andesites possess more radiogenic Sr isotopic compositions, with (⁸⁷Sr/⁸⁶Sr)_i ratios of 0.710–0.717, and more negative ε_Nd (t) values from −11.4 to −1.5, suggesting derivation from an enriched mantle source. Integrating geochemical data with regional geological records, we propose that the eastern part of the Altyn Fault experienced a significant intracontinental extensional setting during the Early Cretaceous, where asthenospheric mantle upwelling played a key role in the generation of the volcanic rocks. This study provides key petrological and geochemical constraints on Early Cretaceous deformation and activity along the Altyn Tagh Fault, and also offers a valuable reference for understanding the evolution of similar fault systems. Full article

Given the increasing demand for water and the need to reduce energy consumption, modern wastewater treatment systems should be characterised by high pollutant removal efficiency while consuming low resources. Hydrophytic wastewater treatment plants with vertical flow through a soil-plant bed (VFCW) are one solution that meets these requirements. The efficiency of these systems largely depends on the biological activity of the bed, of which free-living soil nematodes are an important component. The study presented in this paper aimed to assess the relationship between the quality of domestic wastewater flowing into VFCW beds and the abundance and trophic structure of soil nematode communities. The analysis was carried out on two real-world sites, where VFCW beds were the third stage of the plant bed system. Both treatment plants received only domestic wastewater. Statistical analysis showed no significant differences (p > 0.05) in the physicochemical composition of the wastewater flowing into the two treatment plants, indicating homogeneous system feed conditions. Nevertheless, canonical correspondence analysis (CCA) showed that the relationships between effluent parameters and the abundance of individual nematode trophic groups differed in each bed, suggesting the influence of local environmental and biocenotic conditions. In particular, bacterivorous nematodes—key to bed function—were shown to be sensitive to different sets of variables at the two sites despite similar effluent composition. These results confirm that the rhizosphere—a zone of intense interactions between plant roots, microorganisms, and soil microfauna—plays a critical role in shaping the biological activity of the bed. Nematodes, particularly bacterivorous nematodes, support the mineralisation of organic matter and nutrient cycling, resulting in increased efficiency of treatment processes. The stability of the total nematode abundance, irrespective of inflow conditions, demonstrates the bed biocenosis high ecological resilience to external disturbances. The study’s results highlight the importance of an ecosystem approach in designing and managing nature-based solutions (NBS) treatment plants, which can be a sustainable component of sustainable water and wastewater management. Full article

The emergence of multidrug-resistant microbes presents a serious public health threat that requires new antimicrobial methods. A potential solution to combat resistance involves using metal nanoparticles that possess improved biological characteristics. The researchers have synthesized gold nanoparticles (Au-NPs) using gamma irradiation of Polyacrylamide (PAM) at 5, 10, and 15 kGy doses and through Au/chitosan nanocomposite production methods. They have also assessed the antimicrobial and anticancer functions of the produced nanomaterials by testing them on various microorganisms and cancer cell lines. Gold nanoparticles exhibited strong antibacterial effects against multiple Gram-positive bacterial strains, including Bacillus subtilis, Micrococcus luteus, Staphylococcus epidermidis, Staphylococcus aureus, and Streptococcus mutans, as well as methicillin-resistant Staphylococcus aureus (MRSA). Escherichia coli showed a significant inhibition zone of 23 mm, and Salmonella spp. showed similar inhibition. The inhibition zone for Klebsiella pneumoniae ATCC 13883 revealed resistance. The Au-NPs/chitosan composite showed moderate antifungal effectiveness against Syncephalis racemosum and Aspergillus niger alongside Candida albicans and several other tested fungi. Au-NPs showed cytotoxicity to breast MCF-7 cells, as well as liver HepG-2 cells and colon HCT-116 cells. The combination of Au-NPs with chitosan demonstrated limited effectiveness in countering hepatitis A virus (HAV-10) and herpes simplex virus type 1 (HSV-1). The combination of gamma-irradiated Au-NPs with biopolymers like chitosan demonstrates significant promise in antimicrobial and anticancer biomedical applications. Full article

The primary objective of this research is to simplify and make the industrial manufacturing process of coated maraging steels more economical by combining the advantages of additive manufacturing with simultaneous bulk (aging) and surface (nitriding) treatment in an effective manner. With this aim, preliminary experiments were performed that demonstrated the hardness (and related microstructure) of an as-built MS1 maraging steel, produced by selective laser melting (SLM), is comparable to that of the bulk maraging steel products treated by conventional solution annealing. The direct aging of the solution-annealed and as-built 3D printed maraging steel resulted in similar hardness, indicating that the kinetics of the precipitation hardening process are identical for the steel in both conditions. This assumption was strengthened by a thermodynamic analysis of the kinetics and determination of the activation energy for precipitation hardening using Differential Scanning Calorimetry (DSC) measurements. Industrial target experiments were performed on duplex-coated SLM-printed MS1 steel specimens, which were simultaneously aged and salt-bath nitrided, followed by PVD coating with three different ceramic layers: DLC, CrN, and TiN. For reference, similar duplex-coated samples were used, featuring a bulk Böhler W720 maraging steel substrate that was solution annealed, precipitation hardened, and salt-bath nitrided in separate steps, following conventional procedures. The technological parameters (temperature and time) of the simultaneous nitriding and aging process were optimized by modeling the phase transformations of the entire heat treatment procedure using DSC measurements. A comparison was made based on the in-depth hardness profile estimated by the so-called expanding cavity model (ECM), demonstrating that the hardness of the surface layer of the coated composite material systems is determined solely by the type of the coatings and does not influenced by the type of the applied substrate materials (bulk or 3D printed) or its heat treatment (whether it is a conventional, multi-step treatment or a simultaneous nitriding + aging process). Based on the research work, a proposal is suggested for modernizing and improving the cost-effectiveness of producing aged, duplex-treated, wear-resistant ceramic-coated maraging steel. Full article

Steroidal pharmaceutical wastewater, such as stock liquid and cell lysate, is conventionally treated at a high cost due to its complex composition and high organic content. To treat steroidal pharmaceutical wastewater, make it harmless, and utilize it as a resource, engineering exploration of large-scale biogas engineering was carried out based on its anaerobic digestion characteristics, and the microbial population in the digestion process was analyzed. The results showed that, at a medium temperature of 35 °C and a total solid percentage of 6.5% ± 0.5%, both stock liquid and cell lysate wastewater could be anaerobically fermented normally, with the potential for anaerobic digestion treatment. The cumulative biogas production of lysate gas from the supernatant could reach 758 mL/gVS, which was significantly better than that of traditional raw materials such as straw and feces. The methane content reached 78.9%, and the total VFAs reached 10,204 mg/L on the ninth day. Moreover, we found that co-digestion of steroidal pharmaceutical wastewater with corn straw (CS) significantly enhanced system stability and biogas production efficiency, with synergistic improvement reaching up to 42%. This approach effectively shortened the lag phase observed in the mono-digestion of steroidal pharmaceutical wastewater. Actual treatment in a large-scale biogas project revealed that, after the addition of two kinds of wastewater, the main and auxiliary reactors presented serious acidification problems. Of these, the total volatile fatty acids in the main reactor reached up to 21,000 mg/L, and the methane content in the biogas production decreased to 25%. Additionally, 16S rRNA high-throughput sequencing analysis showed that, after the addition of steroidal pharmaceutical wastewater, the archaea community in the anaerobic reactor changed significantly due to the stress of changes in the fermentation environment. Euryarchaeota became the absolute dominant bacteria, and the methanogenic pathway also changed to the hydrogen trophic methanogenic pathway with Methanothermobacter as the absolute dominant bacterium. This is the first successful industrial-scale application of biogas engineering for treating steroid wastewater, demonstrating its technical feasibility and energy recovery potential. These research outcomes provide critical engineering parameters and practical experience for large-scale resource recovery from similar wastewater streams, offering important reference values for advancing pharmaceutical wastewater treatment from compliance discharge to energy utilization. Full article

In semi-arid regions of Morocco, where the majority of water withdrawals are devoted to irrigation, optimizing irrigation practices in agriculture is a national priority in the face of recurring droughts and growing pressure on groundwater resources. However, the hydrological impacts of different drip-irrigation systems in the soil–plant–atmosphere continuum remain insufficiently understood. We monitored the stable isotope composition (δ²H, δ¹⁸O) across the two agricultural plots in Marrakech (Morocco) with surface drip and subsurface drip irrigation treatments for a complete hydrologic year (June 2022 to June 2023). Weekly to daily samples of rainfall, irrigation water, groundwater, and soil at various depths (5–50 cm) were sampled, and water from branch xylem was extracted using the cryogenic vacuum distillation method. We found that the subsurface irrigation treatment, which delivered water directly to the root zone, maintained narrow isotopic ranges in water of soils beyond 30 cm, as well as in branch xylem and leaf water. By contrast, surface irrigation treatment plots showed pronounced evaporative isotopic enrichment: summer topsoil water δ¹⁸O peaked at −1.1‰ (vs. −8.7‰ in subsurface irrigation treatment), and leaf water reached +13‰ (vs. +8‰ in subsurface). Despite this larger isotopic heterogeneity in surface irrigation site, branch xylem water δ¹⁸O remained within −6 to 2.5‰ across all soil depth, similar to subsurface irrigation treatment, which ranged between −5 and 0‰. This suggests that olive roots accessed soil water uniformly from the upper 50 cm under both irrigation treatments. Seasonal xylem isotopic enrichment in spring and midsummer mirrored shifts towards shallow, evaporatively altered soil water under surface irrigation, but not under the subsurface. The results suggest that subsurface drip irrigation can significantly improve drought resilience and water-use efficiency in the expanding olive sector of the Maghreb, while continuous isotope monitoring serves as a practical approach to enhance sustainable and adaptive water management in water-limited regions. Full article

The construction industry is responsible for a significant amount of greenhouse gas emissions. Therefore, buildings have the potential to play a central role in climate change mitigation. It is also known that building projects are unique and complex, which is why a high degree of process automation is necessary. Two key methods can be employed to calculate the environmental impacts of a construction process: Building Information Modeling (BIM) and Life Cycle Assessment (LCA). Currently, both methods are being considered as a part of advanced building projects. Database (BIM) models can be used as a precise inventory of materials and as an input for LCA. This study aims to (1) review the current status of published BIM-LCA workflows, (2) use a common case study among participants from various countries to compare the individual workflows and the calculated results, (3) identify potential sources of errors in all workflows on the common case study, and (4) provide recommendations and suggestions for developing BIM-LCA models based on the example of the common case study. The outcomes show that the main sources of differences emerge from not including all materials or from the inconsistencies in the exported material lists of the bill of quantities. The reasons for the missing materials stem primarily from the inadequate decomposition of composite materials, oversight of certain materials, and exclusion of thin materials such as foils. Inconsistencies arise from the incorrect handling of composite materials, the grouping of similar materials, and rounding inaccuracies. These issues highlight that errors occur early in the life cycle inventory phase, which forms the foundation of subsequent LCA phases, thereby impacting the final results and potentially leading to inaccurate assessments of environmental impacts. Ensuring accuracy at this stage is therefore critical for supporting reliable sustainability assessments. Consequently, recommendations are proposed to mitigate errors across various stages of the process to enhance the accuracy of LCA outcomes. Full article

Background: Jones fractures of the 5th metatarsal are frequently associated with nonunion due to limited vascularization and repetitive mechanical stress. The aim of the study was to compare the biomechanical performance of T-plate and bicortical screw fixation using standardized 3D models. Methods: Three-dimensional models of the 5th metatarsal were generated from CT images and printed using PolyJet technology (Stratasys J5 DentaJet) using a rigid-elastic composite with properties similar to cortical and cancellous bone. Jones fractures were fixed with either a locked T-plate or a bicortical screw. The samples were tested under axial and oblique static loads (α = 0°, 90°, 180°) and for three values of interfragmentary distance (d = 0.1–1 mm), in a 3 × 2 factorial design. Results: The T-plate fixation recorded a maximum yield force (Fmax) of 149.78 ± 8.53 N (138–161 N), significantly higher compared to the bicortical screw −98.56 ± 2.58 N (96–101 N), (p < 0.05). The ductility index was higher for the plate, indicating a progressive transition to yield. The α and d factors significantly influenced the mechanical behavior, with the polynomial model explaining over 95% of the total variation. Discussion: The plate fixation demonstrated greater strength and superior biomechanical tolerance in imperfect reduction scenarios. The main limitation is the lack of fatigue testing and the inability of 3D models to reproduce the structural heterogeneity of human bone. Conclusions: Implant selection should be individualized based on fracture stability. 3D models provide a reproducible platform for comparative evaluation of osteosynthesis methods, but future studies should include cyclic loading and biological validation. Full article

Objectives: The aim of this study was to assess nutrient intake among individuals adhering to the Christian Orthodox Church (COC) fasting and to investigate potential differences in dietary intake according to Body Mass Index (BMI) classification. Methods: This cross-sectional study enrolled participants through announcements at public universities, churches, and monasteries, targeting both urban and religious adult populations. A total of 228 adults with a BMI exceeding 25 kg/m² were enrolled. Of these, 121 had followed COC fasting practices for at least 10 years or since childhood, while 107 non-fasters were age-matched. Exclusion criteria included age under 18 years, refusal to provide consent, absence from measurements, non-communicable diseases, food allergies, pregnancy, or lactation. Results: Overweight and obesity rates were similar in both groups. Furthermore, there were no statistically significant differences in body composition measurements [body fat %, fat mass (kg), fat free mass (kg), waist circumference]. Diastolic and systolic blood pressure was significantly higher in non-fasters. Non-fasters reported higher intake of sugar, dietary protein, fats (saturated and polyunsaturated), and cholesterol. Fasters consumed lower amounts of vitamin A, vitamins B (B2, B3, B6, B12, folate, pantothenic acid), iron, phosphorus, sodium, zinc, and calcium. Serum folic acid levels were higher, and fasting glucose and phosphorus levels were lower in fasters. Distinct dietary patterns were observed between groups, with fasters consuming more fish and traditional plant-based foods, while non-fasters consumed higher amounts of meat, dairy products, and alcohol. Conclusions: COC fasting is associated with favorable dietary and metabolic profiles, including improved glucose regulation. However, its impact on weight status appears limited. Full article

The Advanced Very High-Resolution Radiometer (AVHRR) onboard NOAA-7 through NOAA-19 satellites has been the primary data source for two Climate Data Records (CDRs) that were developed specifically for Arctic and Antarctic studies: the AVHRR Polar Pathfinder (APP) and Extended AVHRR Polar Pathfinder (APP-x). With the decommissioning of these satellites and the loss of the AVHRR, a method for extending the CDRs with the Visible Infrared Imaging Radiometer Suite (VIIRS) on NOAA’s recent satellites is presented. The goal is to produce long-term, continuous, consistent, and traceable CDRs for polar climate research. As a result, APP and APP-x can now be continued as the VIIRS Polar Pathfinder (VPP) and Extended VIIRS Polar Pathfinder (VPP-x) CDRs. To ensure consistency, a VIIRS Global Area Coverage (VGAC) dataset that is comparable to AVHRR GAC data was used to develop an analogous VIIRS Polar Pathfinder suite. Five VIIRS bands (I1, I2, M12, M15, and M16) were selected to correspond to AVHRR Channels 1, 2, 3b, 4, and 5, respectively. A multivariate regression approach was used to intercalibrate these VIIRS bands to AVHRR channels based on data from overlapping AVHRR and VIIRS observations from 2013 to 2018. The data from 2012 and 2019 were reserved for independent validation. For the Arctic region north of 60°N at 14:00/04:00 Local Solar Time (LST) during 2012–2019, mean biases between APP and VPP composites at a spatial resolution of 5 km are −0.85%/3.03% (Channel 1), −1.22%/3.65% (Channel 2), −0.18 K/0.81 K (Channel 3b), 0.01 K/0.24 K (Channel 4), and 0.07 K/0.19 K (Channel 5). Mean biases between APP-x and VPP-x at a spatial resolution of 25 km for the same region and period are −1.52%/−1.48% for surface broadband albedo, 0.69 K/0.61 K for surface skin temperature, and −0.011 m/−0.017 m for sea ice thickness. Similar results were observed for the Antarctic region south of 60°S at 14:00/02:00 LST, indicating strong agreement between APP and VPP, and between APP-x and VPP-x. Full article

Small areas of flowering plants within urban landscapes can provide much-needed nutrition, shelter, and host plants for pollinating insects and other wildlife. To create such floral displays in gardens, shared spaces, and derelict properties, the use of ‘seed bombs’ (or ‘bee bombs’) is a popular, convenient method for individuals and community groups. Recently, however, the value of seed bombs and wildflower seed mixes has been questioned in terms of seedling establishment, the numbers of species they contain, and whether these species are actually native ‘wildflowers’ as is often claimed. In this study, we obtained 12 brands of seed bombs available in Ireland, with prices ranging from €0.33 to €2.66 per seed bomb. We processed five seed bombs per brand and identified 3083 seeds belonging to 63 species in 22 plant families. The most frequent plant species were Papaver rhoeas L., Phacelia tanacetifolia Benth., and Trifolium alexandrinum L., none of which are native to Ireland. No brands contained only native Irish plants, and one brand obtained from Germany contained no native Irish species. Multivariate analysis identified a cluster of seven brands with similar plant species composition, suggesting they were from the same source or made to the same specifications. Our results suggest that although seed bombs offer a convenient method of producing mixed-flower habitat patches, consumers should be wary that the number of species they contain can be low, they are likely to contain non-native species, and high prices may not reflect the quality of their contents. Full article

Background: Knowledge distillation (KD) compresses deep neural networks by transferring knowledge from a high-capacity teacher model to a lightweight student model. However, conventional evaluation metrics such as accuracy, mAP, IoU, or RMSE focus mainly on task performance and overlook how effectively the student internalizes the teacher’s knowledge. Methods: This study introduces the Knowledge Retention Score (KRS), a composite metric that integrates intermediate feature similarity and output agreement into a single interpretable score to quantify knowledge retention. KRS was primarily validated in computer vision (CV) through 36 experiments covering image classification, object detection, and semantic segmentation using diverse datasets and eight representative KD methods. Supplementary experiments were conducted in natural language processing (NLP) using transformer-based models on SST-2, and in time series regression with convolutional teacher–student pairs. Results: Across all domains, KRS correlated strongly with standard performance metrics while revealing internal retention dynamics that conventional evaluations often overlook. By reporting feature similarity and output agreement separately alongside the composite score, KRS provides transparent and interpretable insights into knowledge transfer. Conclusions: KRS offers a stable diagnostic tool and a complementary evaluation metric for KD research. Its generality across domains demonstrates its potential as a standardized framework for assessing knowledge retention beyond task-specific performance measures. Full article

Hydrogen and oxygen isotopes in atmospheric water vapor (δ_v) and precipitation (δ_p or δ_r) were continuously measured using a laser-based water isotope spectrometer in Guangzhou, southeastern China, from March 2016 to February 2018. The measurements were conducted to investigate the variations in water isotopes in the hydrological cycle under the subtropical monsoon climate. The isotopic composition ranged from −24.4‰ to −11.1‰ for δ¹⁸O in water vapor (δ¹⁸O_v) and from −11.5‰ to 2.3‰ for δ¹⁸O in precipitation (δ¹⁸O_r). The values of δ_v and δ_r were enriched during the dry season and depleted during the wet season, exhibiting systematic seasonal variation. A negative correlation was observed between monthly δ_v and precipitation amount, indicating that the values of δ_v exhibits an ‘amount effect’. However, a corresponding amount effect was not observed in the values of δ_r. The mean difference between δ_v and δ_r was −9.7‰ for δ¹⁸O and −76‰ for δD, suggesting that equilibrium fractionation is the dominant process during precipitation. The local meteoric vapor line (LMVL) for Guangzhou (δD = 6.6δ¹⁸O − 6.4) exhibited a slope similar to that of the equilibrium local meteoric vapor line (ELMVL) but with an intercept difference of 8.6. This difference in intercepts can be attributed to the vertical profile of δ_v. The δD-q (q refers to water vapor concentration) relationship is useful for identifying water vapor sources and tracking isotopic changes during atmospheric transport and precipitation. The local water vapor was found to originate primarily from the mixing of oceanic air masses. Data points falling between the oceanic source mixing line and the Rayleigh curve likely reflect post-condensation processes, such as raindrop re-evaporation or mixing with surrounding ambient vapor. Short periods of heavy precipitation were observed to cause severe depletion in δ_v, resulting in values falling below the Rayleigh curve. Full article

This study evaluated how various types of guar meal in diets of broiler chickens affect their rearing results, carcass composition, and liver histology. The experiment was conducted in one hundred sixty Ross 308 broilers randomly allocated to four groups consisting of the same number of birds (C, GM1, GM2, and GM3). The birds were reared for over 42 days and fed with starter (days 1–21), grower (days 22–35), and finisher (days 36–42) rations. All feed rations were prepared using maize meal, soybean meal, oil, mineral, and feed additives. The experimental factor was guar meal type included in feed rations (starter, grower, and finisher stage) at 6% each: C (control group)—without guar meal, GM1—raw guar meal, GM2—Microlam, and GM3—roasted guar meal. Microlam is a high-protein animal feed produced by laminating and micronizing guar meal for enhanced digestibility and protein content, while roasted guar meal (also called korma) is a more basic protein supplement for livestock and poultry that has undergone roasting to improve its taste and digestibility. It was shown that 6% of raw guar meal in the feed rations affected significantly higher (2646 g) body weight of broilers in comparison to birds fed the same amount of Microlam (2583 g), however feed conversion ratio were similar (1.63–1.65 kg/kg; p > 0.05) in all groups. Thus similar musculature and fatness, broiler chickens from GM1 and GM2 groups obtained higher dressing percentage in compare to group GM3 (p ≤ 0.05). No significant effect of guar meal on the physical characteristics (except pH₁), or the results of the proximate composition of the breast muscles was found. Rations fed to broiler chickens had no effect on the microscopic image of the liver or reaction to the presence of neutral fats. In summary, 6% inclusion of raw guar meal should be recommended in broiler chicken diets as a partial substitute for soybean meal because it contributes to achieving the best growth performance results as well as dressing percentage, without deterioration carcass composition, and liver histology. Full article