Search Results (3,696)

The overhead ground wire (OGW) may fracture at the suspension clamp under short-circuit faults, posing a serious threat to the safe operation of transmission lines. However, the dominant damage mechanism—whether Joule heating or arc discharge—remains unclear. This study investigates a 110 kV OGW breakage accident through combined experimental and numerical approaches. Fracture analysis using scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) revealed composite damage featuring both melting and tensile necking, with no fatigue characteristics. A real-scale short-circuit test platform was constructed, which, for the first time, directly captured intense arc discharge phenomena inside the suspension clamp during current flow. A multi-physics finite element model was then developed to decouple and quantify the thermal contributions of Joule heating and arc heating. Results show that Joule heating alone raises the local temperature to only 49.27 °C—far below the melting points of aluminum (660 °C) and steel (1450 °C). In contrast, arc heating elevates the temperature to over 26,000 °C locally, causing rapid melting of aluminum strands and heating of the steel core above 1450 °C within milliseconds. This extreme heat reduces the effective load-bearing cross-section and tensile strength, ultimately leading to fracture under normal operating tension. The findings demonstrate that arc discharge, rather than Joule heating, is the decisive factor in such failures. This study provides a quantitative theoretical basis for fault protection and hardware design optimization of overhead transmission lines. Full article

Environmental issues such as climate change and cumulative emissions have intensified debate on the effectiveness of public environmental protection expenditure. Traditional Pigouvian taxes and subsidies mainly target instantaneous flow externalities. However, it is difficult to resolve dynamic stock externalities that accumulate over many years, such as climate change and cumulative greenhouse gas emissions, through taxation policies alone. This situation requires the government to make direct environmental protection expenditure to support the ecosystem’s natural assimilation capacity and reduce the rate at which pollution accumulates. This study specifically examines the relationship between stock externalities and environmental protection expenditure within the context of the Turkish economy, which is highly industrialised and under pressure to comply with international environmental commitments such as the European Green Deal and the Paris Climate Agreement. In the study’s empirical analysis phase, long-term relationships between macroeconomic variables and pollution stocks were tested using Fourier cointegration methods and econometric time series analyses. The analysis revealed a long-term co-movement (cointegration) relationship between the series, indicating that public environmental protection expenditures and industrial emissions move in the same direction over the long term. FMOLS and DOLS estimates indicate that environmental protection expenditures are positively associated with industrial emissions in the long run (FMOLS coefficient = 2.1125; DOLS coefficient = 2.0375), whereas renewable energy consumption exerts a negative effect on emissions (FMOLS coefficient = −1.4391; DOLS coefficient = −1.4967). These results suggest that environmental protection expenditure in Türkiye is not independent of current production and industrialisation dynamics, and that its emission-reducing effects are influenced by technological transformation processes. Full article

The vitamin D receptor (VDR) exerts pleiotropic effects essential for human health and modulates the transcription of nuclear factor erythroid 2-related factor 2 (Nrf2), a key regulator of the cellular antioxidant defense system. Polymorphisms represent a major source of interindividual variability and may influence susceptibility to oxidative stress. The VDR polymorphisms ApaI (A > C) and TaqI (T > C) have been associated with disease susceptibility; however, their role in oxidative stress responses during aging remains poorly understood. This study evaluated the association between ApaI and TaqI polymorphisms and susceptibility to oxidative stress-induced cell death, as well as the expression of genes within the VDR–Nrf2 signaling axis, in peripheral blood mononuclear cells (PBMCs) from cognitively healthy Chilean older adults. VDR genotyping was performed using real-time PCR (TaqMan SNP Genotyping Assay), PBMC viability following H₂O₂ exposure was assessed by flow cytometry, and gene expression levels were determined by quantitative PCR (qPCR). For ApaI, homozygous carriers of the A allele showed greater PBMC viability following H₂O₂ exposure (p < 0.0068) and higher mRNA expression levels of Nrf2 (p = 0.0176) and its downstream genes HMOX1 (p = 0.0070) and GST (p = 0.0047) compared with carriers of the C allele (AC or CC). For TaqI, homozygous carriers of the protective C allele exhibited greater PBMC viability (p < 0.0465) and higher Nrf2 (p = 0.0324), HMOX1 (p = 0.0206), and GST (p = 0.0029) expression compared with carriers of the risk T allele (TC or TT). These findings provide novel evidence that VDR polymorphisms may modulate antioxidant responses through regulation of Nrf2-dependent gene expression, suggesting a genetic determinant of oxidative stress resilience in cognitively healthy older adults. Full article

Continuous sap-flow monitoring is a key approach for understanding water-use strategies of shelterbelt species in semi-arid sandy lands. This study investigated two tree species (Populus alba var. pyramidalis Bge. and Pinus sylvestris var. mongholica Litv.) and two shrub species (Salix psammophila C. Wang & C. Y. Yang and Atraphaxis bracteata Losinsk.) in the Zhanggutai region, southern Horqin Sandy Land. Sap flow, environmental variables, and precipitation were continuously measured during the 2019–2020 growing seasons. Stomatal conductance (g_s) and its sensitivity to vapor pressure deficit (VPD) were evaluated. Precipitation dropped from 302.3 mm in 2019 to 106.3 mm in 2020. Daily sap flow peaked mid-season and declined by 21.9%–29.2% during 2020. VPD and solar radiation were primary drivers with narrow response lags. Trees exhibited higher g_s and stronger stomatal sensitivity than shrubs, showing steeper declines as VPD rose, which indicates key drought adaptation and protective mechanisms. Conversely, shrubs maintained a moderate and more stable g_s profile throughout the growing season. In 2020, soil water deficits may force stomatal closure, causing a pronounced drop in baseline g_s and a subsequent decline in sensitivity across all species. This widespread environmental decoupling indicates a critical shift from an atmospheric demand-limited regime during the wet year to a supply-limited regime during the drought year. Overall, trees demonstrated more pronounced stand-scale hydroclimatic sensitivity than shrubs. Given the persistent water consumption by shrubs, our results suggest tree species may offer advantages in later forest restoration stages. Nevertheless, further studies integrating biomass growth and ecosystem water balance are needed to optimize sustainable shelterbelt management. Full article

Olive leaves, a major byproduct of olive processing, are generated in large quantities annually yet suffer from inefficient utilization and low added value. In this study, response surface methodology (RSM) was employed to optimize the extraction conditions of oleuropein from olive leaves. Additionally, the antioxidant activity of purified oleuropein and its protective effect against tret-butyl hydroperoxide (TBHP)-induced oxidative damage in the human embryonic kidney 293 (HEK-293) cell line were investigated. The optimal extraction conditions for oleuropein were determined as follows: extraction temperature of 71 °C, extraction time of 72 min, ethanol concentration of 58%, and solid–liquid ratio of 1:27 (mg/mL), yielding an oleuropein recovery of 44.5%. The extract was purified and identified as oleuropein via Fourier transform infrared spectroscopy (FTIR) and high-performance liquid chromatography (HPLC). Oleuropein exhibited remarkable antioxidant activity and mitigated TBHP-induced oxidative damage in HEK-293 cells by inhibiting apoptosis. TBHP treatment reduced cell viability by approximately 70%, while treatment with 100 and 200 μg/mL oleuropein restored the decreased cell viability to 100%. Morphological observations and 4′,6-diamidino-2-phenylindole (DAPI) staining revealed that TBHP induced apoptotic cell death characterized by nuclear condensation and fragmentation, and this effect was reversed by oleuropein treatment. Flow cytometry analysis showed that TBHP caused approximately 90% cell death, whereas co-treatment with oleuropein reduced cell death to only about 10%. TBHP downregulated the expression of p53, and oleuropein reactivated its expression, highlighting the role of oleuropein in the recovery of the cellular antioxidant system. This study possibly indicated the protective mechanism of oleuropein against oxidative damage-related diseases and provides a theoretical basis for the development of olive leaves as a potential ingredient in functional foods. Full article

To understand the adaptive evolution of endangered plateau freshwater fishes to environmental stress and to better explore the underlying mechanisms in Aspiorhynchus laticeps—a critically endangered fish endemic to the Tarim Basin, Xinjiang, China—a combination of ecological experiments and transcriptome sequencing (RNA-seq) technology was used to study the differences in gene expression patterns among individuals under different salinities and flow conditions. This experiment included four treatment groups (CON, H-SA-S, L-SA, L-SA-S). A. laticeps specimens with an average weight of 2.92 ± 0.62 g and a body length of 58.22 ± 5.10 mm were selected, with three biological replicates for a 96 h combined stress treatment. Moreover, the relationships between these differences and the aquatic environment were analyzed. A total of 1847 differentially expressed genes (DEGs), including 935 upregulated genes and 912 downregulated genes, were identified under different aquatic environment stress modes. GO and KEGG enrichment analyses revealed that TNF signal transduction, the NF-κB pathway, and metabolic regulation were significantly enriched among the DEGs (p < 0.05). High salinity–alkali stress significantly activates the TNF/NF-κB pathway, regulates MST1, LOC107702867, LOC113110979 and other genes to enhance the body’s resistance; water flow changes mainly regulate energy metabolism through genes such as NEHOM01_1600 and gptl. These findings provide an important scientific basis for the ecological adaptability, protection, and proliferation of endemic and endangered fish in China, as well as for germplasm innovation to address ecological deterioration in plateau fishes in alpine and arid areas. This study provides a molecular-level theoretical foundation for artificial habitat regulation and the conservation of endangered Aspiorhynchus laticeps populations in the Tarim River. Full article

Zearalenone is a common mycotoxin that impairs reproductive function, particularly by damaging ovarian granulosa cells. This study investigated the protective effect and underlying mechanism of scutellarin against zearalenone-induced injury in porcine ovarian granulosa cells. Cells were isolated and identified by follicle-stimulating hormone receptor immunofluorescence. Cell viability, cell-cycle distribution, and related molecular changes were evaluated using the MTT assay, flow cytometry, qRT-PCR, and Western blot. Scutellarin showed no obvious cytotoxicity within the tested range and attenuated the zearalenone-induced reduction in cell viability. Flow cytometry analysis demonstrated that scutellarin alleviated zearalenone-induced cell-cycle disturbance. At the molecular level, scutellarin upregulated the expression of cell-cycle-related factors, including CDK1, CDK2, CDK4, and PCNA, and increased the expression of Wnt/β-catenin signaling-related proteins, including WNT5A, β-catenin, c-MYC, and CCND1. WNT5A knockdown further indicated that scutellarin-mediated regulation of PCNA, CDK1, and CDK4 is WNT5A-dependent, whereas its effect on CDK2 may involve a WNT5A-independent mechanism. These findings indicate that scutellarin alleviates zearalenone-induced granulosa cell injury partly through WNT5A-associated modulation of cell-cycle-related proteins, providing mechanistic insights for its protective effects. Full article

Ensuring the sustainability of deep coal mining requires a comprehensive understanding of hydrogeological risks, particularly fault-induced water inrush, which threatens human safety, depletes freshwater resources, and causes irreversible ecological damage. This study addresses the sustainability gap in managing heterogeneous fault fracture zones by conducting coupled loading–seepage experiments on representative limestone, sandstone, coal, and coal–rock mixtures from the Zhaogu No. 2 Mine. Results demonstrate that seepage behavior follows the Forchheimer non-linear regime (E = 0.2–0.95), deviating significantly from Darcy’s law. We quantified that effective stress induces particle crushing and rearrangement, leading to a drastic porosity reduction (up to 97.52% in coal). Crucially, lithology dictates permeability evolution: coal and mixtures exhibit exponential decay, whereas sandstone and limestone follow quadratic functions. The fractal dimension of particles correlates negatively with permeability (R² > 0.95). These findings provide a quantitative framework for predicting water inrush channels, enabling proactive strategies to prevent catastrophic groundwater loss and ensure the long-term viability of mining operations. This research supports SDG 6 (Clean Water) and SDG 12 (Responsible Consumption and Production) by offering scientific guidance for balancing resource extraction with hydrogeological integrity. Full article

Understanding the upstream-attempt behavior of fish in high-flow environments is important for refining behavioral simulations, optimizing fish-passage design, and protecting aquatic ecosystems. This study investigates Schizothorax oconnori, an endemic fish in the Yarlung Tsangpo River on the Qinghai–Tibet Plateau, using a multi-model analytical framework integrating a generalized linear mixed-effects model, Random Forest, SHapley Additive exPlanations, and GeoDetector. Results showed that remaining endurance and nominal flow velocity were positively associated with fish upstream-attempt initiation. Attempt termination reflected endurance depletion, initial endurance, and hydraulic variability. Model-predicted termination probability increased markedly when (i) cumulative endurance consumption during the current attempt exceeded ~11% or (ii) fish began an attempt with an initial endurance status below ~95%. These model-derived change points represent within-attempt endurance depletion and reduced endurance available at attempt initiation, respectively. Across attempt sequences, the dominant explanatory factors showed an apparent shift from physiological condition during the first attempt to hydraulic variability during subsequent attempts. This sequence-related pattern is consistent with behavioral adjustment based on repeated experience in the flow environment, although cumulative fatigue, stress, individual differences, and experimental procedures may also contribute. Hydraulic-variability metrics along the trajectory showed greater explanatory importance than several instantaneous hydraulic variables, and physiological condition and hydraulic variability together enhanced explanatory power. This study provides a quantitative multi-model framework for analyzing upstream-attempt behavior and offers a scientific basis for refining behavioral simulations and optimizing fish-passage facilities. Full article

To reveal the impacts of long-term coal mining on groundwater flow fields and the environment, the Jinjitan Coal Mine in Shaanxi Province, China, was selected as the study area. A systematic investigation on the evolution of flow fields and migration of pollutants under long-term coal mining impact was conducted using methods including Self-Organizing Map (SOM) clustering analysis, water isotope analysis, and numerical simulation. The results show that groundwater in the study area is mainly derived from atmospheric precipitation, and the mine water is a mixture of 55% coal seam water and 45% Quaternary groundwater; long-term coal mining has led to two types of Quaternary groundwater level changes (stable and continuously declining); The groundwater level of the Jurassic aquifer shows an overall decline. However, where the aquifer is locally recharged by the Quaternary groundwater, the groundwater level shows a decline-then-rise variation. The overall groundwater flow field maintains the pattern of runoff from northeast to southwest and discharge into the Yuxi River, with no local or regional groundwater depression cones observed; numerical simulation results indicate an average groundwater level drop of 1.36 m over an 10-year period, with a maximum decrease of 4.89 m; the migration scope of oxygen demand and petroleum pollutants caused by domestic sewage pond leakage is limited, their maximum long-term (3650 d) migration distances are 253.47 m and 254.27 m, respectively, and their concentrations are far below the limit of the Class III groundwater quality standard. The research findings provide a scientific basis for the environmental protection, rational development, and utilization of groundwater in the Jinjitan Coal Mine area. Full article

Ochratoxin A (OTA) is a widespread nephrotoxic mycotoxin that contaminates cereal grains and feed, posing serious threats to animal health and food safety. Although curcumin has been reported to exert protective biological activities, it remains unclear whether its protection against OTA-induced renal epithelial injury is mediated by broad transcriptomic reversal or by selective regulation of key survival pathways. This study investigated the protective effect of curcumin against OTA-induced apoptosis in porcine renal epithelial (PK-15) cells and explored the underlying molecular mechanism using transcriptome sequencing combined with molecular validation. PK-15 cells were treated with 8 μg/mL OTA (approximately 19.8 μmol/L), 10 μmol/L curcumin, or their combination. Cell viability, LDH release, apoptotic morphology, mitochondrial membrane potential (ΔΨm), and apoptosis rate were assessed by CCK-8, LDH assay, Hoechst 33342 staining, JC-1 staining, and flow cytometry. Transcriptome sequencing was performed to identify global gene expression changes and key signaling pathways, followed by qRT-PCR and Western blot validation of apoptosis-related factors and the PI3K/AKT/mTOR pathway. OTA markedly reduced cell viability, increased LDH release, induced nuclear condensation and apoptotic body formation, and decreased ΔΨm. Transcriptome analysis revealed that OTA caused extensive transcriptional dysregulation (11,707 differentially expressed genes), whereas curcumin selectively modulated 498 genes, of which 380 overlapped with OTA-responsive genes. KEGG enrichment identified the PI3K-Akt signaling pathway as a key regulatory target. At the mRNA level, OTA upregulated Bax and Caspase-3 and downregulated Bcl-2; corresponding changes were observed at the protein level, and curcumin reversed these effects. Furthermore, OTA reduced the mRNA levels of PI3K, AKT, and mTOR and the protein abundance of PI3K, p-AKT, and mTOR, whereas curcumin partially restored these changes. In conclusion, curcumin alleviates OTA-induced mitochondrial apoptosis in PK-15 cells mainly by restoring PI3K/AKT/mTOR-associated survival signaling and Bcl-2/Bax/Caspase-3 balance rather than by broadly reversing the entire transcriptomic disturbance. These findings provide mechanistic insight into curcumin-mediated protection against OTA-induced renal epithelial toxicity. Full article

Background/Objectives: Alzheimer’s Disease (AD) and vascular dementia contribute up to ~75% of dementia cases, as determined via autopsy. AD arises in part due to the buildup of aberrant proteins (amyloid beta (Aβ) and Tau); vascular dementia is caused by reduced cerebral blood flow. Each dementia mechanisms damages brain. Bobola et al. found that their low-intensity focused ultrasound (FUS) protocol applied to the brains of the 5XFAD mouse model of AD reduced Aβ by 50% through activation of microglia. Eguchi et al. found that their own FUS protocol applied to the brains of the same mouse model reduced Aβ by 15% and increased cerebral blood flow by 50% through an increase in endothelial nitric oxide synthase (eNOS). Here, we sought to test a combined version of those two FUS protocols, expecting both a decrease in Aβ burden and an increase in eNOS. Methods: Using a diagnostic ultrasound probe, we applied our combined FUS protocol primarily to the left hippocampus of anesthetized 5XFAD mice, for an hour a day, for three days for younger mice and for five days for older mice. On day three or five, respectively, we harvested their brains and performed histological analysis to assess Aβ burden, microglial activation and their co-localization with Aβ, as well as the burden of eNOS within neuronal nuclei (here called intra-neuronal eNOS) and outside of neurons. Results: Relative to untreated mice, the treated younger mice had more activated microglia co-localized with Aβ and reduced Aβ burden for large plaques, as well as no change in each measure of eNOS. In contrast, the treated older AD mice had no change in activated microglia co-localized with Aβ, and no change in Aβ burden. However, relative to untreated older AD mice, FUS decreased total and extra-neuronal eNOS and increased intra-neuronal eNOS. Conclusions: The ability of our FUS protocol to reduce Aβ burden and alter the eNOS distribution depends critically upon the age of the AD mice (more Aβ plaques for a comparable number of microglia for older mice relative to younger mice) and duration of the treatment. The observed decrease in extra-neuronal eNOS distribution in older AD mice caused by FUS raises the concern that our protocol may increase ischemia, while the increase in intra-neuronal eNOS may counteract that effect via protection of synaptic function. These findings also identify two candidate therapeutic windows for our FUS treatment protocol, each requiring more research before translation to humans. One window is early intervention to maximize Aβ plaque removal via activation of microglia. The second is later intervention to protect synaptic function if it is possible to mitigate the potential ischemic risk caused by the differential effects of FUS on eNOS. Full article

The topical application of ferulic acid (FA) is limited by its low solubility and high susceptibility to oxidation. To overcome these limitations, the multicomponent system Cicloferulic^® (CF) was developed by mixing FA, hydroxypropyl β-cyclodextrin (HPβ-CD), and polyvinylpyrrolidone K30 (PVP K30), which demonstrated greater safety and antioxidant efficacy than FA alone. The physicochemical characterization of FA, CF, and their components showed greater thermal stability and reduced crystallinity of CF, indicating the formation of the system. In cytotoxicity assays on HaCaT cells, FA maintained cell viability only up to 500 µg/mL, while CF maintained viability even at 10.000 µg/mL, demonstrating 20 times greater safety than FA. In cellular antioxidant activity assays, FA and CF showed similar effects at low concentrations. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method, CF and FA reduced more than 70% of DPPH; however, CF contains only 12% FA, indicating an eightfold greater efficiency than FA. Formulations containing FA and CF increased the Sun Protection Factor (SPF) in vitro, even with a 50% reduction in UV filters. However, they did not stabilize formulations with intrinsically photolabile UV filters. In release studies, FA exhibited rapid flow, while CF promoted a modified release profile. Thus, CF stands out as an innovative, multifunctional system that can improve the stability, safety, and efficacy of FA for topical applications. Full article

Against the dual backdrop of the global green transition and China’s construction of a unified national market, the impact of environmental policies on the spatial allocation of capital has emerged as a core concern for academic researchers and policymakers alike. China’s implementation of the Environmental Protection Tax Law in 2018 completed the historic transition from the long-standing pollution discharge fee system to a formal environmental tax regime. While differentiated interprovincial tax rates under the new regime have the potential to reshape cross-regional capital flow patterns, existing literature lacks systematic micro-level empirical evidence regarding how environmental tax reform affects firms’ cross-regional investment and the underlying mechanisms driving such effects. This study constructs a sample of Chinese A-share-listed firms covering the period 2012 to 2024 and applies the difference-in-differences (DID) method to systematically examine the causal impact, transmission channels, and heterogeneous boundary conditions of environmental tax reform on firms’ cross-regional investment. The baseline estimation results confirm that environmental tax reform significantly stimulates cross-regional investment activities among firms located in provinces that raised environmental tax rates after the reform. This core conclusion remains robust across a series of validity checks, including parallel trend assumption tests, placebo tests, propensity score matching combined with difference-in-differences (PSM-DID) estimation, and the exclusion of confounding effects from contemporaneous policy interventions. Mechanism analysis identifies two core transmission channels through which the reform exerts its effects: rising pollution abatement costs and alleviation of corporate financing constraints. Further heterogeneity tests reveal that the promoting effect of the reform on cross-regional investment is more prominent for capital-intensive firms and firms located in regions with lower fiscal pressure and firms operating in regions with stricter environmental law enforcement. This study provides new micro-level empirical evidence supporting the applicability of both the pollution haven hypothesis and the Porter hypothesis in the Chinese institutional context and offers actionable policy insights for optimizing the design of the environmental tax system, guiding corporate green transformation, and facilitating coordinated regional development. Full article

Active area protection against unauthorized UAV swarms requires coordinated target assignment strategies that account for both low-level physical capabilities and the stochastic, consumptive nature of physical interceptions. This paper presents a decentralized target assignment framework based on probabilistic flow optimization. By utilizing an aerodynamics-aware flight model, we derive a probabilistic prior to capture the geometric dependency of terminal interception success under high-velocity maneuvers. Modeling the defense process as a probabilistic consumption flow couples initial tactical assignments with conditional transition flows, allowing surviving defensive assets to be proactively redistributed to secondary unauthorized intrusions. To resolve this problem under practical communication and sensing constraints, we develop the Distributed Flow-regularized Market-based Consensus (DFMC) algorithm. The proposed algorithm decomposes the global optimization into localized subproblems and employs a water-filling projection to plan secondary paths. Simulation results demonstrate that the proposed framework yields improved interception rates and better spatial resource dispersion compared to conventional auction-based baselines, while maintaining stable scalability in dense interception scenarios. Full article