Search Results (268)

Hydraulic fracturing is a core stimulation technology for enhancing hydrocarbon production. However, it faces significant technical bottlenecks in unconventional reservoirs. These bottlenecks include poor adaptability to high-temperature and high-salinity environments, water-sensitive formation damage, and insufficient long-term fracture conductivity. Nanotechnology leverages unique properties of nanomaterials, such as surface effects, quantum size effects, and designability. Nanotechnology offers systematic solutions for optimizing fracturing fluids, enhancing proppant performance, and innovating waterless fracturing techniques. This review outlines the current status of fracturing technology, exploring the role of nanoparticles in improving fluid rheology, proppant strength, and interface regulation, and discusses future challenges. Studies show that nanomodified fracturing fluids can increase high-temperature viscosity retention by over 300%. Meanwhile, waterless fracturing reduces water consumption by 80%. Despite challenges in particle agglomeration and cost, nanotechnology demonstrates significant potential in boosting recovery and reducing environmental impact. Nanotechnology is positioned as a transformative technology for future unconventional resource development. Full article

Despite the widespread use of dithiocarbamate fungicides such as maneb, mancozeb, metiram, propineb, thiram, and ziram detected, according to EU legislation, via common degradation product carbon disulfide (CS₂), recent and comprehensive reviews on analytical methods for their determination in plant-based foods are lacking. Given the well-documented toxicity shown by the experimental model for these pesticides, including neurotoxicity and endocrine disruption, harmonized and reliable analytical protocols are crucial for food safety monitoring and regulatory compliance. Dithiocarbamates, beyond CS₂ release, have been associated with immunotoxicity, thyroid dysfunction, and potential carcinogenicity, raising further concern regarding chronic dietary exposure. Their metabolites may disrupt enzymatic activity and oxidative balance, enhancing systemic toxicity. Early methods, had limited sensitivity, poor reproducibility, and relied on hazardous solvents, reducing practical value. Although later advancements improved detection limits, modern procedures, including those proposed by the European Union Reference Laboratory (EURL), still show limitations. The EURL-recommended protocol involves acid hydrolysis using concentrated HCl, extraction with isooctane, heating to 85 °C, and rapid ice-bath cooling, which poses environmental concerns. Recovery efficiency remains inconsistent in some cases, and reproducibility within commodity groups is poor. This review discusses the status of methods for determining dithiocarbamates as individual compounds and via CS₂ moiety. Full article

Agri-food supply chains have experienced notable changes in recent decades, with tomatoes (Solanum lycopersicum) maintaining their status as a key global crop in terms of both production and consumption. These supply chains comprise a complex network of stakeholders—including producers, processors, distributors, and retailers—who collectively ensure the delivery of tomatoes from farms to consumers. This study develops mathematical models of agri-food tomato supply chains (AFTSCs) and examines their behavior through stability analysis and dynamic simulations based on a compartmental approach. Furthermore, the environmental impact is evaluated using a sustainability index, to which the waste diversion rate is introduced. This metric is defined as the proportion of diverted waste (i.e., materials recycled, reused, or composted) relative to the total waste generated, thereby enabling the quantification of sustainability performance within the system. Finally, a sensitivity analysis is conducted on the proposed dynamical models to validate and reinforce the findings. Full article

Background: Cognitive difficulties involving memory and concentration significantly affect individuals’ daily functioning and quality of life, influenced by demographic, clinical, and socio-environmental factors. This study aimed to examine the national prevalence and distribution of cognitive difficulties in Saudi Arabia, explore regional and gender disparities, and identify demographic and clinical predictors. Methods: Data were obtained from the 2017 Saudi National Disability Survey, a population-based, cross-sectional study involving 20.4 million Saudi citizens. Twelve indicators related to cognitive difficulty—covering severity, educational and marital status, consanguinity, duration, causes, and regional distribution—were analyzed, integrating baseline population data from three national surveys. Results: Results indicated that 1.1% (224,408 individuals) reported cognitive difficulties, predominantly alongside other disabilities (1.0%), while only 0.2% reported it exclusively. Cognitive difficulties were significantly higher in Al-Riyadh and Makkah Al-Mokarramah, with residents of Aseer and Hail facing doubled odds compared to Najran. Gender disparities were evident; males predominated in extreme severity and congenital or accident-related cases, whereas females showed higher proportions of disease-related causes, mild severity, and prolonged disability (≥25 years). Independent predictors included severe and extreme severity, disease-related causes, consanguinity, and long duration. Conclusions: These findings highlight critical regional and gender-based inequities and underscore the need for targeted policies emphasizing early detection, gender-sensitive interventions, and region-specific resource allocation to meet Saudi Arabia’s Vision 2030 objectives for inclusive health and social services. Full article

The safety of composite insulators in high-voltage transmission lines is directly related to the stable operation of the power system, which is a fundamental condition for the normal functioning of people’s lives and industrial production. Composite insulators are exposed to outdoor conditions for extended periods of time, and with the increase in service life, they are subjected to aging due to external environmental factors and electrical stresses. This aging leads to a decline in their electrical insulation, mechanical properties, and other performance, which, in severe cases, may result in power system failures. Therefore, accurate assessment and detection of the aging status of composite insulators are particularly important. Traditional detection methods such as visual inspection, hardness testing, and hydrophobicity testing have limitations, including single functionality and susceptibility to environmental interference, which cannot comprehensively and accurately reflect the aging condition of the insulators. In recent years, spectroscopy-based detection technologies have been increasingly applied for the rapid detection of composite insulators due to their advantages, such as high sensitivity, non-contact measurement, and multi-dimensional information extraction. Common spectroscopic detection methods include Ultraviolet Discharge (UV Discharge), Fourier Transform Infrared (FTIR) Spectroscopy, Raman Spectroscopy (RS), Hyperspectral Imaging (HSI), Laser-Induced Breakdown Spectroscopy (LIBS), and Terahertz (THz) Spectroscopy. These methods offer non-contact, remote, and rapid capabilities, enabling detailed analysis of the insulator’s surface microstructure, chemical composition, and aging characteristics. This paper introduces = spectroscopy-based methods for detecting the aging status of composite insulators, analyzing the advantages and limitations of these methods, and discussing the challenges of their industrial application. Furthermore, the paper reviews the research progress and practical applications of spectroscopic techniques in the evaluation of insulator aging status, systematically summarizing important achievements in the field and providing an outlook for future developments. Full article

Background/Objectives: Multiple chemical sensitivity (MCS) is a complex environmental illness characterized by intolerance to various environmental chemicals, affecting multiple organ systems. Despite its prevalence, MCS remains poorly understood, with limited recognition by the World Health Organisation amid challenges in diagnosis due to symptom heterogeneity. This study aimed to investigate the oxidative stress status in patients diagnosed with MCS compared to healthy controls, focusing on plasma and erythrocyte markers. Methods: Blood samples from 40 MCS patients and 40 controls were analyzed for lipid peroxidation (LPO), total antioxidant activity (TAA), adenosine triphosphate (ATP), and antioxidant enzyme activities, alongside glutathione cycle components. Results: Results revealed no significant differences in plasma LPO or TAA between groups, with a reduction in 61% ATP levels in MCS subjects. However, erythrocyte analysis showed reduced levels of glutathione (GSH) and total glutathione in MCS patients. Glutathione peroxidase (GPx) activity also decreased by 15% in erythrocytes of MCS patients, suggesting increased hydrogen peroxide detoxification at the expense of oxidation of GSH to glutathione disulfide (GSSG). Because glutathione reductase activity (GRd) did not change, this GSSG could not be reduced, the GSSG/GSH ratio increased by 46%, indicating heightened intracellular oxidative stress. Catalase (CAT) activity also remained unchanged (reduced by 9%, non-significant). Conclusions: These findings highlight the role of oxidative stress in MCS pathophysiology, particularly the disruption of the glutathione cycle within erythrocytes. The study underscores the need for further research into the molecular mechanisms underlying MCS to improve diagnostic criteria and therapeutic strategies. Understanding intracellular oxidative imbalances may provide insights into the systemic dysfunction observed in MCS patients. Full article

Background: Breast cancer is the most common malignancy affecting women worldwide and continues to pose significant challenges despite progress in early detection and personalized therapies. While its pathogenesis has traditionally been associated with genetic, hormonal, and environmental factors, recent studies have highlighted the potential role of dysbiosis—an imbalance in gut and systemic microbiota—in breast cancer development and progression. This article aims to examine the mechanisms through which systemic dysbiosis may contribute to breast cancer risk and explore its therapeutic implications. Methods: This study seeks to analyze and compare the fecal microbiota profiles of breast cancer patients and healthy individuals from a single center in Craiova, Romania, in order to identify microbial signatures linked to breast cancer and BRCA mutation status. Special attention is given to the gut–liver axis and its influence on estrogen circulation, a key factor in hormone-sensitive breast cancers. Results: Evidence suggests that dysbiosis can influence breast cancer progression by promoting chronic inflammation, impairing immune regulation, and altering estrogen metabolism through the gut–liver axis. These effects may contribute to tumor development, immune evasion, and therapeutic resistance. Interventions aimed at restoring microbial balance show promise in preclinical studies for mitigating these effects. Conclusions: Systemic dysbiosis represents a potentially modifiable risk factor in breast cancer. Microbiota profiling may serve as a useful biomarker for risk stratification and therapeutic response. Future research into microbiome-based interventions could offer novel approaches for prevention and treatment in breast cancer care. Full article

Exhaled breath analysis (EBA) is an advanced, non-invasive diagnostic technique that utilizes volatile organic compounds (VOCs) to detect and monitor various diseases. This review examines EBA’s historical development and current status as a promising diagnostic tool. It highlights the significant contributions of modern methods such as gas chromatography–mass spectrometry (GC-MS), ion mobility spectrometry (IMS), and electronic noses in enhancing the sensitivity and specificity of EBA. Furthermore, it emphasizes the transformative role of nanotechnology and machine learning in improving the diagnostic accuracy of EBA. Despite challenges such as standardization and environmental factors, which must be addressed for the widespread adoption of this technique, EBA shows excellent potential for early disease detection and personalized medicine. The review also highlights the potential of photonic crystal fiber (PCF) sensors, known for their superior sensitivity, in the field of EBA. Full article

Municipal sewage sludge is a potential soil amendment rich in organic matter and nutrients, yet its reuse is often constrained by heavy metal contamination. This study evaluated six heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) in sludge collected from seven centralized wastewater treatment plants in Bangkok, Thailand, by analyzing physicochemical properties, total metal concentrations, and chemical speciation. Three ecological risk indices, the geo-accumulation index (I_geo), risk assessment code (RAC), and potential ecological risk index (PERI), were applied to assess contamination status, mobility, and ecological threat. The sludge exhibited high levels of organic matter and essential nutrients, indicating potential for agricultural reuse; however, elevated electrical conductivity at some sites may pose salinity risks if unmanaged. Speciation analysis revealed that Cd and Zn were largely present in mobile and redox-sensitive fractions, Cr and Pb were primarily in stable residual forms, and Cu and Ni occurred in moderately mobile forms influenced by environmental conditions. Across all indices, Cd consistently posed the highest ecological risk, followed by Zn, in a site-dependent manner, while Cr and Pb represented low risk. These findings provide a clearer understanding of metal behavior in sewage sludge and underscore the importance of integrating chemical speciation with multi-index risk assessment in sludge management. Incorporating such approaches into national guidelines, particularly in countries lacking established heavy metal limits, can strengthen monitoring frameworks, guide safe and sustainable reuse, and support regulatory development in contexts with limited monitoring data. Full article

Ionizing radiation is a well-known environmental stressor capable of generating excessive reactive oxygen species (ROS), leading to oxidative damage in sensitive tissues, including the reproductive system. While oxidative stress is increasingly implicated in male reproductive dysfunction, the long-term effects of low-dose-rate (LDR) radiation on testicular structure and oxidative status remain underexplored. In this study, mice were exposed to continuous LDR radiation (0.39, 1.29, and 3.46 mGy/h) for 21 days to assess testicular histopathology and oxidative status. Although testis weight did not significantly differ among groups, histological analysis revealed basal membrane disruption and reduced spermatogenic cell populations in irradiated groups. Masson’s Trichrome and Sirius Red staining demonstrated dose-dependent collagen deposition, indicating progressive testicular fibrosis. TUNEL assays confirmed increased germ cell apoptosis in the mid- and high-dose-rate groups. ROS levels were significantly elevated only in the highest-dose group, suggesting a threshold-dependent oxidative stress response. These findings indicate that chronic LDR radiation induces testicular damage primarily through apoptosis and fibrosis, with oxidative stress potentially contributing at higher exposure levels. Full article

Monitoring water quality in narrow tributary bays of large river-type reservoirs is hindered by sparse sampling and cloud-limited imagery. This study develops a Trophic State Index (TSI) inversion for Xiangxi Bay, a major tributary bay of the Three Gorges Reservoir, using Landsat data and a backpropagation (BP) neural network, with hyperparameters tuned via a grid search algorithm (GSA). Environmental drivers such as water temperature, solar radiation, and photosynthetically active radiation were combined with Landsat spectral bands. Eleven sites measured monthly in 2009 yielded 98 samples after preprocessing, and training achieved R² = 0.94. Predictions for 2009 show clear spatiotemporal heterogeneity: those for April and September (TSI = 48–59) exceeded those for July and October (46–56), with mid–lower reaches (52–59) being higher than mid–upper reaches (47–54). Out-of-period predictions for April/June 2019 and August/November 2020 were consistent with seasonal expectations, with higher spring–summer TSIs (2019: 50–57; 2020 August: 45–55) than in November 2020 (37–47). Key limitations include the small sample size, cloud-related data gaps, and sensitivity to evolving reservoir operations. This framework demonstrates a practical route to the satellite-based monitoring and mapping of trophic status in narrow reservoir tributaries. Full article

PM_2.5 is an air pollutant that has a direct link to increased cardiovascular and respiratory morbidity and mortality, which has been demonstrated in numerous studies. Existing research highlights species-specific variations in the capacity of trees to capture and retain particulate matter (PM). However, a critical gap remains regarding sensitivity analyses of i-Tree Eco model assumptions. Such analyses are crucial for validating the model’s PM deposition estimates against empirically derived efficiencies, a deficiency that the present study addresses. The study consisted of two steps: a tree inventory was carried out at three selected sites, based on which, an ecosystem service analysis was performed using i-Tree Eco, and samples were taken from the leaves of trees at the analysed sites, which were the basis for comparing the data from the i-Tree Eco method and laboratory methods. The study focused on comparing PM_2.5 and PM₁₀ removal estimates derived from both the model and laboratory measurements. The results revealed significant discrepancies between the modelled and laboratory values. A comparison of the average annual PM₁₀ accumulation measured using laboratory methods for individual tree species showed that Tilia sp. achieved 24%, Fraxinus sp. 47.6%, Aesculus sp. 50.77%, and Quercus robur 23.4% of the PM₁₀ uptake efficiency estimated by the i-Tree Eco model. For PM_2.5 uptake, the values obtained through both methods were more consistent. Furthermore, trees growing under more challenging environmental conditions exhibited smaller diameter at breast height (DBH) and lower PM₁₀ and PM_2.5 removal efficiency according to both methods. While I-Tree Eco incorporates tree biophysical characteristics and health status, its methodology currently lacks the resolution to reflect site-specific environmental conditions and local pollutant concentrations at the individual tree level. Therefore, laboratory methods are indispensable for calibrating, validating, and supplementing i-Tree Eco estimates, especially when applied to diverse urban environments. Only the combined application of empirical and model-based methods provides a comprehensive understanding of the potential of urban greenery to improve air quality. Full article

Both behavioral intentions and structural constraints shape household waste disposal in low-resource settings. This study integrates the Theory of Planned Behavior (TPB) with Environmental Justice (EJ) to examine informal waste disposal in Vhembe District, South Africa, a region marked by infrastructural deficits and uneven municipal services. A cross-sectional survey of 399 households across four municipalities assessed five disposal behaviors, including river dumping and domestic burial. Only 8% of households used formal bins, while over 50% engaged in open or roadside dumping. Although education and income were inversely associated with harmful practices, inadequate service access was the most significant constraint on formal disposal. Logistic regression revealed that rural residents and households in underserved municipalities were significantly more likely to engage in hazardous methods, regardless of socioeconomic status. These findings extend TPB by showing that perceived behavioral control reflects not only psychological agency but also material and institutional limitations. By reframing informal disposal as a structurally conditioned response rather than a behavioral deficit, the study advances EJ theory and provides a transferable TPB–EJ framework for decentralized, justice-oriented waste governance. The results underscore the need for Sustainable Development Goal (SDG)-aligned interventions that integrate equitable infrastructure with context-sensitive behavioral strategies. Full article

Evaluating the response of maize crops to different nitrogen fertilization rates is essential to ensure their agronomic, environmental, and economic efficiency. In this study, the spectral information of maize plants subjected to five distinct nitrogen fertilization strategies was analyzed. The fertilization strategies were based on the practices commonly used in maize fields in the study area, with the aim of ensuring the research findings’ applicability. The spectral reflectance was measured using a spectroradiometer covering the 350–2500 nm range, and the results enabled the identification of optimal spectral regions for monitoring plants’ nitrogen status, particularly in the visible and infrared ranges. A Principal Component Analysis (PCA) of the reflectance data revealed the key wavelengths most sensitive to the nitrogen availability: 555 nm and 720 nm during the vegetative stage and 680 nm during the reproductive stage. This information will support the development of drone-mounted multispectral sensor systems for large-scale monitoring, as well as the design of low-cost sensors for early nitrogen deficiency detection. Furthermore, the study demonstrated the feasibility of estimating the cornstalk nitrate content based on direct reflectance measurements of maize stems. The prediction model showed satisfactory performance, with a coefficient of determination (R²) of 0.845 and a root mean square error of prediction (RMSECV) of 2035.3 ppm, indicating its strong potential for predicting the NO₃-N concentrations in maize stems. Full article

Temperature fluctuations caused by climate change and global warming pose a threat to fish. The burbot (lota lota) population is particularly sensitive to increased water temperature, but the systematic impacts of high-temperature exposure on their liver and intestinal health remain unclear. In January of 2025, we collected wild adult burbot individuals from the Ussuri River (water temperature: about 2 °C), China. The burbot were exposed to 2 °C, 7 °C, 12 °C, 17 °C, and 22 °C environments for 96 h; then, the liver and intestinal contents were subsequently collected for histopathology observation, immunohistochemistry, biochemical index assessment, and transcriptome/16S rDNA sequencing analysis. There was obvious liver damage including hepatocyte necrosis, fat vacuoles, and cellular peripheral nuclei. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities were elevated and subsequently decreased. Additionally, the malondialdehyde (MDA) level significantly increased with increasing temperature. These results indicate that 7 °C (heat stress temperature), 12 °C (tipping point for normal physiological metabolism status), 17 °C (tipping point for individual deaths), and 22 °C (thermal limit) are critical temperatures in terms of the physiological response of burbot during their breeding period. In the hepatic transcriptome profiling, 6538 differentially expressed genes (DEGs) were identified, while KEGG enrichment analysis showed that high-temperature stress could affect normal liver function by regulating energy metabolism, immune, and apoptosis-related pathways. Microbiomics also revealed that acute heat stress could change the intestinal microbe community structure. Additionally, correlation analysis suggested potential regulatory relationships between intestinal microbe taxa and immune/apoptosis-related DEGs in the liver. This study revealed the potential impact of environmental water temperature changes in cold habitats in winter on the physiological adaptability of burbot during the breeding period and provides new insights for the ecological protection of burbot in the context of global climate change and habitat warming. Full article