Search Results (875)

Salmonella is a major foodborne pathogen that poses an increasing threat due to the emergence of mcr-1-mediated colistin resistance. However, data on mcr-1-positive Salmonella in pork products are limited. In this study, 457 samples collected in 2023 from pig slaughterhouses in Guangdong province were investigated to determine the prevalence and genomic characteristics of mcr-1-positive Salmonella isolates. We found that 92 Salmonella isolates (20.1%, 92/457) were recovered, representing six serotypes, including Salmonella Typhimurium (n = 29) and Salmonella Rissen (n = 29). High resistance to tetracycline (90.2%, 83/92) and multidrug resistance (58.7%, 54/92) were observed. Critically, two colistin-resistant Salmonella Kentucky ST198 isolates (2.2%) harboring mcr-1 on transferable IncI2 plasmids were identified. Genomic analysis revealed a novel multidrug resistance region (MRR, ~57 kb) inserted into the bcfH locus (containing floR, qnrS1, bla_CTX-M-55, and aph (3’)-Ia) and a variant Salmonella Genomic Island 1 (SGI1-KI, containing tet (A), sul1, qacEΔ1 and aadA7) in these isolates. The MRR and SGI1-KI may enhance bacterial survival under antibiotic selection pressure. Phylogenetic analysis showed close relatedness to human clinical strains, suggesting food chain transmission. The findings highlight a high antimicrobial resistance burden, the emergence of transferable last-resort colistin resistance (mcr-1), and acquisition of complex resistance determinants (MRR, SGI1-KI), underscoring an urgent need for enhanced “One Health” surveillance. Full article

Landsat time series data, which have become freely available in recent years, are commonly used to detect changes in land cover and monitor ecosystem disturbances. Thyme habitats are areas under protection due to their high ecological value. However, human activity leading to land use competition, mainly from overgrazing, poses an increased threat to these habitats. The impact of these disturbances is underreported, and their detection remains essential for thyme conservation. The island of Lemnos was chosen as the study area, because of the significant areas of thyme habitats, which are currently under pressure due to rural abandonment, desertification, overgrazing, and systematic fires in recent decades. A long-term Landsat time series was generated, and the Normalized Difference Vegetation Index (NDVI) was calculated. The change detection algorithm (BFAST) was used to detect and characterize significant changes (breakpoints) within the time series and compare them to local fire events. The analysis showed that Lemnos thyme habitats have been significantly reduced in size due to fires and their conversion to new grazing areas for livestock production. Measures should be taken to conserve thyme habitats with the participation of local stakeholders, including livestock farmers and beekeepers. Satellite monitoring techniques are important tools that could facilitate this conservation process. Full article

In petroleum production processes, the water used to maintain formation pressure often plays a key role and is pumped into injection wells to compensate for the pressure drop in the formation after oil extraction and displacement of the remaining petroleum products to the development well. The source of such water may be produced by waters extracted together with oil and previously purified from mechanical impurities and hydrocarbons. However, a significant disadvantage of using such water is the presence of pollutants such as sulphur-reducing bacteria (SRB) and a high content of hydrogen sulfide. Traditional purification methods against them show low efficiency. Hydrogen sulfide and SRB are not only a threat of environmental pollution, but they also pose a high risk to pipelines in the petroleum industry due to an increase in the rate of metal corrosion. In this paper, formation water was treated with a field deployment flow-mode plasma discharge unit. A significant decrease in the growth rate of SRB in treated water was achieved. Bacterial growth was suppressed for up to 14 days after three treatment cycles of treatment. The hydrogen sulfide content was reduced by 33% after one cycle of plasma discharge water treatment. Full article

Background. Antimicrobial resistance (AMR) poses a significant global health threat, necessitating a deeper understanding of bacterial adaptation mechanisms. Introduction. This study investigates the genotypic and phenotypic evolutionary trajectories of Escherichia coli under meropenem and gentamicin selection, and it benchmarks these findings against florfenicol-evolved strains. Methodology. Utilizing a downsized, three-layer acrylic modified “Microbial Evolution and Growth Arena (MEGA-plate) system”—scaled to 40 × 50 cm for sterile handling and uniform 37 °C incubation—we tracked adaptation over 9–13 days, enabling real-time visualization of movement across antibiotic gradients. Results. Meropenem exposure elicited pronounced genetic heterogeneity and morphological remodeling (filamentous and circular forms), characteristic of SOS-mediated division arrest and DNA-damage response. In contrast, gentamicin exposure produced a uniform resistance gene profile and minimal shape changes, suggesting reliance on conserved defenses without major morphological adaptation. Comprehensive genomic analysis revealed a core resistome of 22 chromosomal loci shared across all three antibiotics, highlighting potential cross-resistance and the central roles of baeR, gadX, and marA in coordinating adaptive responses. Gene ontology enrichment underscored the positive regulation of gene expression and intracellular signaling as key themes in resistance evolution. Discussion. Our findings illustrate the multifaceted strategies E. coli employs—combining metabolic flexibility with sophisticated regulatory networks—to withstand diverse antibiotic pressures. This study underscores the utility of the MEGA-plate system in dissecting spatiotemporal AMR dynamics in a controlled yet ecologically relevant context. Conclusions. The divergent responses to meropenem and gentamicin highlight the complexity of resistance development and reinforce the need for integrated, One Health strategies. Targeting shared regulatory hubs may open new avenues for antimicrobial intervention and help preserve the efficacy of existing drugs. Full article

The agricultural sector plays a vital role in achieving the second Sustainable Development Goal: “Zero Hunger”. To ensure food security, agriculture must remain resilient and productive. In Indonesia, a major rice-producing country, the conversion of agricultural land for non-agricultural uses poses a serious threat to food availability. Accurate and timely mapping of paddy rice is therefore crucial. This study proposes a phenology-based mapping approach using a Convolutional Neural Network-Random Forest (CNN-RF) Hybrid model with multi-temporal Sentinel-2 and Landsat-8 imagery. Image processing and analysis were conducted using the Google Earth Engine platform. Raw spectral bands and four vegetation indices—NDVI, EVI, LSWI, and RGVI—were extracted as input features for classification. The CNN-RF Hybrid classifier demonstrated strong performance, achieving an overall accuracy of 0.950 and a Cohen’s Kappa coefficient of 0.893. These results confirm the effectiveness of the proposed method for mapping paddy rice in Indramayu Regency, West Java, using medium-resolution optical remote sensing data. The integration of phenological characteristics and deep learning significantly enhances classification accuracy. This research supports efforts to monitor and preserve paddy rice cultivation areas amid increasing land use pressures, contributing to national food security and sustainable agricultural practices. Full article

Under the dual pressures of climate change and anthropogenic activities, the sustainability of the fragile ecosystem on the Qingzang Plateau has garnered considerable attention. This study, taking the Yarlung Tsangpo River, Lhasa River, and Nianchu River Basin (YNL) of Xizang as a case study, systematically assesses the spatiotemporal evolution of its ecosystem services from 2000 to 2020. It reveals a critical dynamic: while regional ecosystem services have shown an overall improving trend over the past two decades, driven jointly by a warmer and wetter climate and ecological engineering projects, the adverse impacts of human activities have intensified significantly, posing an emerging and growing threat to regional ecological security. Based on the InVEST model, this research quantifies four key services and constructs a Comprehensive Ecosystem Service (CES) index to evaluate the overall ecosystem function. Subsequently, an integrated Principal Component Analysis and Partial Least Squares Structural Equation Modeling (PCA-PLS-SEM) analytical framework is employed to decouple the complex pathways driving CES successfully. The results confirm that climate and topography are the fundamental natural drivers determining the spatial pattern of ecosystem services, which is characterized as being high in the east and low in the west. The core contribution of this study lies in its quantitative identification of the coexisting reality of “ecological improvement” and “development pressure” in the region. It emphasizes that future management strategies must urgently shift from a static conservation approach to an integrated paradigm capable of proactively addressing human–land contradictions. This provides a critical scientific basis for safeguarding China’s national ecological security barrier. Full article

This study addresses the effects of climate variability and land-use change on groundwater recharge in Major Groundwater Reservoir 406 (MGR 406) in southeastern Poland, a key strategic water resource. It focuses on how regional shifts in precipitation patterns and spatial development influence the volume and distribution of renewable groundwater resources. The analysis integrates meteorological data (1951–2024), groundwater modeling outputs, groundwater-use data, and land cover changes from CORINE datasets (1990–2018). A spatial assessment of hydrogeological conditions was performed using the Groundwater Resources Assessment Index (GRAI), combining drought frequency, recharge conditions, land-use classes, and groundwater extraction levels. Results indicate a long-term increase in annual precipitation alongside more frequent but shorter drought episodes. Urban expansion and land sealing were found to reduce infiltration efficiency, particularly in and around the city of Lublin, where the highest extraction rates were recorded. The assessment identified several zones of high threat to groundwater resources, which have no sufficient legal protection. These findings highlight the need to integrate groundwater management into local spatial planning and land management strategies. The study concludes that balancing water use and recharge potential under evolving climate and land-use pressures are essential to ensuring the sustainability of groundwater resources in MGR 406. Full article

The perforating–fracturing–testing combined technology has emerged as a crucial well completion technique to enhance production efficiency. However, the shock loads generated during perforation in the packed section of an oil and gas well significantly affect the stability of the perforating tubing string system, potentially leading to deformation or even fracture. During the perforating operation, a large amount of blast products is generated, and as these products escape the perforating gun and interact with the perforating fluid, the fluid pressure pulsates. These pressure fluctuations are the primary cause of the dynamic response of the perforating tubing string. The greatest threat to tubing string integrity occurs when pulsating pressure reaches its peak amplitude, potentially leading to tubing failure. To address this, this study employs underwater explosion theory to analyze the pressure variations during the generation and propagation of shock waves in perforation operations. Additionally, quantitative numerical simulation analysis reveals key relationships governing peak perforating fluid pressure: peak pressure remains remarkably stable at 370–371 MPa despite variations in perforating fluid viscosity (0–110 cP) or tubing Young’s modulus (100–260 GPa). However, it responds significantly to other parameters: fluid density (1–3 g/cm³) causes a linear increase from 335 MPa to 598 MPa; total charge mass drives a proportional rise from 162 MPa to 388 MPa; detonation interval (0–50 μs) elevates pressure from 268 MPa to 378 MPa; and formation pressure (0–100 MPa) increases it from 315 MPa to 372 MPa. Crucially, peak pressure decreases from 376 MPa to 243 MPa as the explosion space expands (0–5 m³). Furthermore, a nonlinear regression model is developed to predict peak perforating shock loads. The results indicate that residual perforation energy critically impacts tubing string safety. Validated against two field cases, the model achieves nearly 10% error compared to predictions from Pulsfrac (industry-standard perforating shock software), meeting field requirements while providing actionable insights for wellbore integrity and perforating tubing string stability. Full article

The Yarlung Zangbo River (With a total length of 2057 km, the river forms part of the Ganges–Brahmaputra River system), located in the core region of the Tibetan Plateau, hosts a unique yet fragile aquatic ecosystem. Fish populations inhabiting this ecosystem have been significantly impacted by external factors, leading to declining resources. This decline is particularly evident in local tributaries, including the DuoXiong Zangbo River—a main tributary where scientific research remains scarce due to its geographic remoteness. Consequently, the status of schizothoracinae in this river remains poorly understood, necessitating research on their population structure, growth characteristics, and resource dynamics, as well as the extent of external disturbances. During the 2023–2024 season, fishery surveys were conducted during two sampling periods: summer (June–July) and autumn (September–October). This study focuses on the Duoxiong Zangbo River, a tributary of the Yarlung Zangbo River, targeting three schizothoracinae fish species: Schizothorax o’connori, Oxygymnocypris stewartii, and Ptychobarbus dipogon. The results show that their body lengths ranged from 23.02 to 440.00 mm, 23.02 to 460.00 mm, and 45.18 to 418.00 mm, with body weights ranging from 0.30 to 1394.30 g, 0.20 to 1013.00 g, and 1.20 to 814.30 g. Age distributions spanned 0–14, 0–16, and 0–13 years, respectively, indicating a trend toward younger and smaller individuals. Von Bertalanffy growth modeling revealed asymptotic body lengths (L_∞) of 591.233 mm, 507.557 mm, and 515.292 mm, with growth coefficients (k) of 0.098, 0.122, and 0.118, respectively. These parameters suggest that the populations are exhibiting accelerated growth strategies in response to fishing pressure. Using FiSAT II, exploitation rates (E) were calculated as 0.547, 0.758, and 0.711 for the three species, with predicted maximum sustainable exploitation rates of 0.579, 0.882, and 0.884, respectively. These findings indicate that the three schizothoracinae species have approached the threshold of overexploitation and are facing threats of overexploitation. In summary, this study demonstrates that schizothoracinae in the DuoXiong Zangbo River are experiencing adverse effects from external pressures, with populations at risk of decline. These results underscore the urgent need for targeted conservation and management strategies. Full article

The current global energy crisis is one of the most pressing challenges of the 21st century, it highlights the fragility of an old power system based on fossil fuels, geopolitical dependencies and often the precariousness and age of equipment and installations, affecting the economy, security and social stability on a national, regional and world scale. The risk of blackout thus becomes not only a technological threat, but a symbol of the need for a paradigm shift. The energy future must be sustainable, collaborative and adaptable—to guarantee not only the continuity of services with electricity, but also the stability of modern society. This paper provides an intrinsic interdisciplinary analysis on the causes, implications and possible solutions related to major imbalances in contemporary power systems, emphasizing the growing risk of blackout (large power outages). The main causes of crises are analyzed interdisciplinary, such as: insecurity in the functioning of the National Power System, terrorist attack on the National Power System, extreme weather condition, natural calamity, energy insecurity and political/military insecurity. The paper highlights the interdependence between energy infrastructure and energy security, as well as the vulnerability of power grids to cyberattacks, natural disasters and consumer pressures. In addition, socio-economic, technological and political issues are addressed, providing an integrated view of the phenomenon. Finally, national, regional and bilateral mitigation, limitation and restoration (resilience) procedures and measures are proposed in the event of an electricity crisis—blackout. Full article

Avalanches occur frequently in mountainous areas and pose significant threats to roads and infrastructure. Clarifying how terrain conditions influence avalanche initiation and movement is critical to improving hazard assessment and response strategies. This study focused on a wet-snow slab avalanche that occurred on 26 March 2024, in the Simutas region of the northern Tianshan Mountains, Xinjiang, China. The authors combined remote sensing imagery, high-resolution meteorological station observations, field investigations, and numerical simulations (RAMMS::Avalanche) to analyze the avalanche initiation mechanism, dynamic behavior, and path recurrence characteristics. Results indicated that persistent heavy snowfall, rapid warming, and substantial daily temperature fluctuations triggered this avalanche. The predominant southeasterly (SE) winds and the northwest-facing (NW) shaded slopes created favorable leeward snow deposition conditions, increasing snowpack instability. High-resolution meteorological observations provided detailed wind, temperature, and precipitation data near the avalanche release zone, clearly capturing snowpack evolution and meteorological conditions before avalanche initiation. Numerical simulations showed a maximum avalanche flow velocity of 19.22 m/s, maximum flow depth of 12.42 m, and peak dynamic pressure of 129.3 kPa. The simulated avalanche deposition area and depth closely matched field observations. Multi-temporal remote sensing images indicated that avalanche paths in this area remained spatially consistent over time, with recurrence intervals of approximately 2–3 years. The findings highlight the combined role of local meteorological processes and terrain factors in controlling avalanche initiation and dynamics. This research confirmed the effectiveness of integrating remote sensing data, high-resolution meteorological observations, and dynamic modeling, providing scientific evidence for avalanche risk assessment and disaster mitigation in mountain regions. Full article

Due to global warming, extreme temperature events have become increasingly prevalent, posing significant threats to both socioeconomic development and human safety. While previous studies have extensively examined the influence of individual climatic circulation systems on extreme temperature, the combined effects of multiple concurrent circulation patterns remain poorly understood. Using daily temperature data from 29 meteorological stations in Chongqing (1960–2019), this study employs linear trend analysis, correlation analysis, and random forest (RF) models to analyze spatiotemporal variations in the intensity and frequency of extreme temperature. We selected 21 climate indicators from three categories—atmospheric circulation, sea surface temperature (SST), and sea-level pressure (SLP)—to identify the primary drivers of extreme temperatures and quantify their respective contributions. The key findings are as follows: (1) All extreme intensity indices exhibited an increasing trend, with the TXx (annual maximum daily maximum temperature) showing the higher trend (0.03 °C/year). The northeastern region experienced the most pronounced increases. (2) Frequency indices also displayed an upward trend. This was particularly evident for the TD35 (number of days with maximum temperature ≥35 °C), which increased at an average rate of 0.16 days/year, most notably in the northeast. (3) The Western Pacific Subtropical High Ridge Position Index (GX) and Asia Polar Vortex Area Index (APV) were the dominant climate factors driving intensity indices, with cumulative contributions of 26.0% to 33.4%, while the Western Pacific Warm Pool Strength Index (WPWPS), Asia Polar Vortex Area Index (APV), North Atlantic Subtropical High Intensity Index (NASH), and Indian Ocean Warm Pool Strength Index (IOWP) were the dominant climate factors influencing frequency indices, with cumulative contributions of 46.4 to 49.5%. The explanatory power of these indices varies spatially across stations, and the RF model effectively identifies key circulation factors at each station. In the future, more attention should be paid to urban planning adaptations, particularly green infrastructure and land use optimization, along with targeted heat mitigation strategies, such as early warning systems and public health interventions, to strengthen urban resilience against escalating extreme temperatures. Full article

The scope and scale of commercial captive lion breeding (CLB) in South Africa have rapidly increased since the 1990s. We conducted a qualitative systematic review using the PRISMA protocol to determine whether CLB provides a sustainable supply side intervention to reduce pressure on wild lion populations. A search was performed using three academic databases for sources published between 2008 and 2023. We collated and reviewed the data using an evaluation framework to determine the potential benefits and threats of CLB in the context of conservation. Among the 126 peer-reviewed and 37 grey literature articles identified, we found evidence suggesting that the framework’s criteria were not fully met, raising concerns that CLB may facilitate the demand for lions, their parts, and derivatives. Our findings further indicate a reasonable cause to doubt that the CLB provides a sustainable supply side intervention to meet the commercial demand for lions, their parts, and derivatives. This could adversely impact conservation of wild lion populations. We conclude that further research is required to effectively evaluate the purported conservation benefits of CLB. These insights may also have implications for the policy and governance of commercial predator breeding operations in South Africa and globally. Full article

Pseudomonas aeruginosa poses significant health threats due to its multidrug-resistant profile, particularly affecting immunocompromised individuals. The pathogen’s ability to produce virulence factors and antibiotic-resistant biofilms, orchestrated through quorum-sensing (QS) mechanisms, complicates conventional therapeutic interventions. This review aims to critically assess the potential of anti-QS strategies as alternatives to antibiotics against P. aeruginosa infections. Comprehensive literature searches were conducted using databases such as PubMed, Scopus, and Web of Science, focusing on studies addressing QS inhibition strategies published recently. Anti-QS strategies significantly attenuate bacterial virulence by disrupting QS-regulated genes involved in biofilm formation, motility, toxin secretion, and immune evasion. These interventions reduce the selective pressure for resistance and enhance antibiotic efficacy when used in combination therapies. Despite promising outcomes, practical application faces challenges, including specificity of inhibitors, pharmacokinetic limitations, potential cytotoxicity, and bacterial adaptability leading to resistance. Future perspectives should focus on multi-target QS inhibitors, advanced delivery systems, rigorous preclinical validations, and clinical translation frameworks. Addressing current limitations through multidisciplinary research can lead to clinically viable QS-targeted therapies, offering sustainable alternatives to traditional antibiotics and effectively managing antibiotic resistance. Full article

The Tibetan-Himalayan region, recognized as a global biodiversity hotspot, is increasingly threatened by the dual pressures of climate change and human activities. Understanding the vulnerability of plant species to these forces is crucial for effective ecological conservation in this region. This study employed an improved Climate Niche Factor Analysis (CNFA) framework to assess the vulnerability of six representative alpine endemic herbaceous plants in this ecologically sensitive region under future climate changes. Our results show distinct spatial vulnerability patterns for the six species, with higher vulnerability in the western regions of the Tibetan-Himalayan region and lower vulnerability in the eastern areas. Particularly under high-emission scenarios (SSP5-8.5), climate change is projected to substantially intensify threats to these plant species, reinforcing the imperative for targeted conservation strategies. Additionally, we found that the current coverage of protected areas (PAs) within the species’ habitats was severely insufficient, with less than 25% coverage overall, and it was even lower (<7%) in highly vulnerable regions. Human activity hotspots, such as the regions around Lhasa and Chengdu, further exacerbate species vulnerability. Notably, some species currently classified as least concern (e.g., Stipa purpurea (S. purpurea)) according to the IUCN Red List exhibit higher vulnerability than species listed as near threatened (e.g., Cyananthus microphyllus (C. microphylla)) under future climate change. These findings suggest that existing biodiversity assessments, such as the IUCN Red List, may not adequately account for future climate risks, highlighting the importance of incorporating climate change projections into conservation planning. Our study calls for expanding and optimizing PAs, improving management, and enhancing climate resilience to mitigate biodiversity loss in the face of climate change and human pressures. Full article