Search Results (163,104)

This paper investigates the impact of green credit policy (GCP) on the green technological innovation capacity of heavily polluting enterprises (HPEs) from the perspectives of external financing and internal concerns. Using data from companies in China’s A-share market from 2008 to 2021, we study the shocks of Green Credit Guidelines to the green technological innovation in HPEs based on the difference-in-differences (DID) model. The baseline regression result reveals that the GCP significantly motivates HPEs to engage in green technological innovation. Moreover, the efficiency of capital utilization has an adverse moderating effect on the impact of GCP, while commercial credit financing has a positive moderating effect. Mechanism analysis shows that the GCP stimulates green technological innovation in HPEs by reinforcing short-term loan dependence and strengthening executive green awareness. In a further study, the policy effects are heterogeneous for enterprises with different characteristics. Regionally, green credit policy affects enterprises in China’s eastern region more strongly. The effect is also more pronounced for Chinese domestic enterprises and those with low financial background heterogeneity within top management teams. Overall, the findings in this study have important implications for policymakers in implementing green finance policies. Full article

To promote the sustainable application of self-compacting lightweight aggregate concrete (SCLC) in cold regions and mitigate river sand shortages by substitution, this study investigates the impact of manufactured sand (MS) content on its freeze–thaw resistance. However, the micro-damage mechanism and a reliable damage model for MS-SCLC under freeze–thaw conditions remain lacking. Five groups of SCLC with varied manufactured sand content (0%, 30%, 60%, 80%, and 100%) were prepared. This study examined the behavior of SCLC under freeze–thaw conditions, with a focus on its frost durability and microstructural evolution. Furthermore, an SCLC freeze–thaw damage model for the manufactured sand content was established based on the Weibull distribution. Increasing the manufactured sand content conferred benefits on the compressive strength loss rate and relative dynamic elastic modulus; however, it had adverse consequences for the apparent morphology and mass loss rate. In conclusion, the SCLC mixture containing 60% manufactured sand displayed superior frost resistance, demonstrating a mass loss rate of 4.79%, a relative dynamic elastic modulus of 0.624, and a compressive strength loss rate of 38.46% after 200 freeze–thaw cycles. The identified optimal MS content (60%) and the established Weibull-based damage model provide crucial quantitative guidance for designing durable MS-SCLC structures in freeze–thaw environments. Full article

With the rapid proliferation of digital multimedia in resource-constrained Internet of Things (IoT) environments, there is growing demand for efficient image compression combined with secure data embedding. Existing Vector Quantization (VQ)-based Reversible Data Hiding (RDH) methods prioritize embedding capacity while neglecting reconstruction fidelity, often introducing noticeable quality degradation in edge regions—unacceptable for high-fidelity applications such as medical imaging and forensic analysis. This paper proposes a lightweight RDH framework with a once-offline trained VQ codebook that simultaneously performs secure data embedding and visual quality enhancement for VQ-compressed images. Quality Improvement Codes (QIC) are generated from pixel-wise residuals between original and VQ-decompressed images and embedded into the VQ index table using a novel Recoding Index Value (RIV) mechanism without additional transmission overhead. Sobel edge detection identifies perceptually sensitive blocks for targeted enhancement. Comprehensive experiments on ten standard test images across multiple resolutions (256 × 256, 512 × 512) and codebook sizes (64–1024) demonstrate Peak Signal-to-Noise Ratio (PSNR) gains of +4 to +5.39 dB and Structural Similarity Index Measure (SSIM) improvements of +4.12% to +9.86%, with embedding capacities approaching 100 Kbits. The proposed approach consistently outperforms existing methods in both image quality and payload capacity while eliminating computational overhead of deep learning models, making it highly suitable for resource-constrained edge devices and real-time multimedia security applications. Full article

Open burning of crop residue is a major source of air pollutants in China. While a nationwide straw burning ban implemented in 2016 has proven effective in reducing primary emissions, its impact on ozone (O₃), a key pollutant detrimental to human health, remain poorly quantified. This study aims to assess the impact of straw burning on downwind urban O₃ pollution and to investigate the complex mechanisms governing O₃ changes resulting from transported agricultural fire plumes. Here, using multi-satellite data and ground observations from 2013 to 2020, this study developed a method to identify smoke-affected days and estimate plume transport time over northern China. The results show that the straw burning ban effectively reduced peak concentrations of particulate matter (PM_2.5) during harvest seasons. However, O₃ responses on smoke-affected days were heterogeneous, showing both increases and decreases. The random forest model revealed the meteorological and chemical drivers of O₃ variability. Elevated formaldehyde (HCHO) and temperatures promote O₃ production, while higher NO₂ and relative humidity enhance its titration. Trajectory analysis further decoupled the mechanisms that O₃ and HCHO enhancements were primarily driven by local photochemistry, whereas NO₂ increases were attributable to regional transport and mixing with anthropogenic pollution. This study underscores the necessity for integrated air quality management strategies that account for the complex trade-offs between PM_2.5 and O₃ to fully realize the public health benefits of emission control policies. Full article

Concealed conductive connections between a transmission tower’s grounding grid and its foundation can cause a portion of the lightning strike current to enter the foundation and concentrate at the concealed conduction locations, thereby increasing the risk of foundation deterioration. To investigate the impact characteristics of such currents on the foundation under this operating condition, this study first establishes an electro-thermal-mechanical coupled finite-element model of the tower foundation that incorporates a subsurface concealed conductive loop, and compares the foundation’s temperature rise and mechanical characteristics under lightning currents and under power-frequency follow currents. The results indicate that power-frequency follow current poses a substantially greater hazard to the foundation than lightning current. Based on similarity theory, scaling laws for the foundation subjected to the impacts of power-frequency follow current are then derived. Considering that the intrinsic electro-thermal properties of the foundation cannot be altered in the scaled model, a parameter correction method is proposed according to quasi-similarity criteria. The corrected scaled-model results are compared with those of the prototype in simulation, and principal indicators exhibit deviations within 3%. A physical scaled model was subsequently designed and fabricated for impact testing, and ultrasonic inspection was used to assess potential damage in the concealed conduction region. The results show that under the action of power-frequency follow currents, the maximum temperature at the concealed conductive region reaches 124 °C, with deviations of 2.83% from the prototype simulation and 3.58% from the scaled-model simulation. The tower foundation was subjected to 20 power-frequency follow current impacts. After each impact and subsequent cooling, ultrasonic measurements of wave propagation velocity at the concealed conduction center decreased from 3.797 km/s to 3.571 km/s. The observed reduction in wave speed indicates a loss of local concrete structural integrity and suggests the risk of performance degradation and initiation of microcracks. These findings provide a reference basis for assessing the safety of tower foundations under concealed conduction conditions. Full article

This study presents a comprehensive techno-economic assessment of offshore wind projects in the Colombian Caribbean, emphasizing the impact of site-specific parameters on development costs and performance. Wind resource conditions were evaluated in four coastal regions (La Guajira, Magdalena, Atlántico, and Bolívar) using hourly meteorological data from 2015 to 2024, adjusted to 100 m above ground level through logarithmic and power law wind profile models. The analysis included wind speed, bathymetry, distance to shore, distance to substation, foundation type, wind power density (WPD), and capacity factor (C_f). Based on these parameters, annual energy generation was estimated, and both capital expenditures (CAPEX) and operational expenditures (OPEX) were calculated, considering the technical and cost differences between fixed and floating foundations. Results show that La Guajira combines excellent wind conditions (WPD of 796 W/m² and C_f of 61.5%) with favorable construction feasibility (bathymetry of −32 m), resulting in the lowest CAPEX among the studied regions. In contrast, Magdalena and Atlántico, with bathymetries exceeding 200 m, require floating foundations that more than double the investment costs. Bolívar presents an intermediate profile, offering solid wind potential and fixed foundation feasibility at a moderate cost. The findings confirm that offshore wind project viability depends not only on wind resource quality but also on physical site constraints, which directly influence the cost structure and energy yield. This integrated approach supports more accurate project prioritization and contributes to strategic planning for the sustainable deployment of offshore wind energy in Colombia. Full article

The increasing occurrence of extreme rainfall events often leads to flash floods, infrastructure damage, loss of human life, and significant economic impacts. There is a pressing need for data-driven assessments and the application of robust analytical approaches to better understand these changes. Analyzing ground-level daily rainfall data from 1985 to 2023 from 26 monitoring stations, this study first employs the Mann–Kendall test using robust statistics including minimum, median, various quartiles, and maximum rainfall values for detecting long-term trends across Saudi Arabia. Next, the k-means clustering technique is applied to characterize the annual rainfall cycles across different regions of the country. Finally, the Peaks Over Threshold (POT) approach within Extreme Value Theory (EVT) is employed to identify site-specific thresholds for extreme rainfall using the Generalized Pareto Distribution (GPD). This automated, data-driven method offers a more objective alternative to the commonly used ad hoc percentile-based threshold selection, thereby enhancing the rigour and reproducibility of extreme rainfall analysis. Local specific thresholds were computed ranging from about 16 to 47 mm from Arar and Jazan, respectively. These thresholds were then used to calculate the frequency and intensity of extreme rainfall events. The fitted GPD parameters were further used to estimate return levels (RLs) for different return periods (2-, 5-, 10-, 20-, 50-, and 100-year) into the future. The results underscore considerable spatial variability in extreme rainfall behaviour across Saudi Arabia, with a higher likelihood of intense and infrequent precipitation events in the coming decades. Full article

In this paper, a strategy is proposed based on the microstructuring of GaAs substrates by photolithography combined with nanostructuring by electrochemical etching for the purposes of obtaining GaAs nanowire domains in selected regions of the substrate. The micropatterning is based on previously obtained knowledge about the mechanisms of pore growth in GaAs substrates during anodization. According to previous findings, crystallographically oriented pores, or “crysto pores,” grow along specific crystallographic directions within the GaAs substrates, with preferential propagation along the <111>B direction. Taking advantage of this feature, it is proposed to pattern the (111)B surface by photolithography and to, subsequently, apply anodization in an HNO₃ electrolyte. It is shown that the areas of the GaAs substrate under the photoresist mask are protected against porosification due to the growth of pores perpendicular to the surface of the substrates in such a configuration. Pores overlapping under adjusted electrochemical etching conditions results in the formation of GaAs nanowire arrays in the substrate regions not covered by photoresist. Thermal annealing conditions in an argon atmosphere with a low oxygen concentration were developed for the selective oxidation of GaAs nanowires, thus producing a wide-bandgap Ga₂O₃ nanowire pattern on the GaAs substrate. It is shown that the morphology of nanowires can be controlled by adjusting the electrochemical parameters. Smooth-walled nanowire arrays were obtained under specific conditions, while perforated and wall-modulated nanowires were formed when crystallographic pores intersected at a higher applied anodizing potential. Full article

Objectives: The emergence of SARS-CoV-2 variants with enhanced immune evasion capabilities poses ongoing challenges for maintaining population-level immunity. This study aim to evaluate neutralizing antibody responses to the wild-type (WT) strain and the Omicron sublineage XBB.1.9 in the Israeli population using serum samples collected between August 2022 and January 2023, prior to widespread circulation of XBB.1.9. Methods: Pseudovirus-based microneutralization assays incorporating variant-specific spike proteins were employed to measure neutralizing geometric mean titers (GMTs) across subgroups categorized by age, gender, socioeconomic status, and geographic region. Results: Neutralizing titers against XBB.1.9 were significantly lower than those against WT across all demographic groups, with a 29-fold reduction in neutralization activity against XBB.1.9, underscoring the immune escape potential of XBB.1.9. For WT, older adults (≥65 years) exhibited higher titers than younger individuals (p < 0.01), whereas no significant age-related differences were observed for XBB.1.9 (p > 0.05). Regional disparities in WT immunity were identified, with higher titers in Northern Israel compared to Jerusalem and Southern regions. By contrast, XBB.1.9 neutralization showed no significant regional variation. Conclusions: These findings demonstrate substantially reduced neutralization of XBB.1.9 compared to WT and reveal disparities in WT immunity by age and region. The results emphasize the need for updated vaccines targeting immune-evasive variants and for tailored vaccination strategies to address regional and demographic gaps in protection. Full article

Portugal contributed to the global diffusion of sweetpotato (Ipomoea batatas L. Lam.). Although it is of minor importance on the Portuguese mainland, it is one of the most common crops in the Azores and Madeira archipelagos and is highly relevant in the Portuguese ex-colonies Mozambique and Timor-Leste. We analyzed the genetic diversity and population structure of sweetpotato from these five geographic provenances using twelve nuclear simple sequence repeat (SSR) markers. We studied 45 accessions, 15 of which were collected from farmers’ fields in these five regions and 30 of which are held at “Banco de Germoplasma de Moçambique”. The SSR markers showed a high level of polymorphism and a high number of alleles per locus. Population structure analyses using Bayesian clustering (STRUCTURE) grouped accessions from farmers’ fields into two groups and divided samples of “Banco de Germoplasma de Moçambique” into three groups. A principal coordinate analysis (PCoA), based on the Bruvo distance, supported the population structure analysis. Concerning the genebank accessions, the two analyses indicated three clusters, all of them containing Mozambican landraces. From our results, it may be concluded that sweetpotato populations from the three countries do not share a common genetic background, despite the shared history of the countries. Full article

Mine water injection and storage (MWIS) represent a crucial method for the management of unconventional water resource in the mining regions of China. The flow fields and patterns within heterogeneity porous media during the MWIS process are complex and significantly influenced by well configurations. This study aims to offer a numerical perspective for the evaluation of MWIS flow fields and patterns associated with diverse well configurations in different heterogeneous aquifers. The simulation results of various well configuration scenarios, including vertical, slanted and horizontal wells, demonstrate that well configuration exerts a profound influence on the flow fields and patterns of MWIS. The injected mine water primarily spreads radially and groundwater level gradually diminishes as the distance from the wellbore increases in the vertical well. Conversely, horizontal wells can notably augment the contact area between the injected mine water and the aquifer, leading to a more uniform distribution of the flow field and higher injection efficiency. Slanted wells exhibit a combination of vertical and horizontal flow characteristics, which can be adjusted in accordance with specific geological conditions to optimize the MWIS effect. Overall, both horizontal and slanted wells exhibit water storage capacities that are approximately 1.77 to 2.65 times greater than that of vertical wells. Effective mine water capacity accumulates primarily during the initial phase, followed by a rapid decline in subsequent reserves. The results suggest that appropriate arrangement of well configurations and injection pressure can effectively enhance the MWIS efficiency. Hydraulic fracturing is the fundamental approach to sustaining MWIS capacity. This research provides a theoretical foundation and practical guidance for the design and optimization of MWIS, which is of great significance for the sustainable development of coal mines in the Ordos Basin, China. Full article

This study evaluates the impact of applying biochar alongside nitrogen fertilizer on soil aggregates and aggregate-associated carbon through a two-year experiment under irrigated conditions in North Xinjiang. In 2021, a randomized block design established 36 experimental plots. The experiment employed a factorial design with three levels of nitrogen fertilizer and four levels of biochar. Measurements of soil aggregates and aggregate-associated organic carbon were taken in 2022. This study’s objectives were to quantify biochar’s effect on soil aggregation and stability and to determine the distribution of SOC across different aggregate sizes. The results indicated that macroaggregates (> 2 mm and 0.25–2 mm) were most common (N2B1, N2B2, and N2B3), making up 75.57–78.46% of all aggregates. In treatments with reduced nitrogen and biochar (N2B1, N2B2, and N2B3), soil aggregate refractory organic carbon content was significantly higher compared to other treatments. Generally, applying reduced nitrogen with moderate biochar (N2B2) significantly increased soil organic carbon and refractory organic carbon levels, aiding carbon fixation and improving soil carbon storage. Thus, biochar application effectively enhances carbon storage in agricultural soils, offering valuable insights for improving soil fertility in irrigated regions of northern Xinjiang. Full article

Sustainable landslide risk management is critical for achieving resilient communities and supporting the United Nations Sustainable Development Goals, particularly in vulnerable mountainous regions of developing countries. This study presents experimental evidence supporting dimensionless analysis approaches for characterizing granular flow behavior, contributing to cost-effective landslide hazard assessment frameworks. We designed a 4 m experimental flume to investigate the influence of particle characteristics on flow velocity and runout distance, using two materials with contrasting shapes but similar density (~460 kg/m³) and nominal size (~5 mm): uniform crystal beads (φ = 25.2°) and non-uniform crushed granite particles (φ = 36.9°). High-resolution imaging (30 fps, 2336 × 1752 pixels) captured 30 flow experiments from initiation to deposition. Results demonstrate significant differences in flow behavior: crystal beads achieved 50% longer runout distances and 46% higher maximum velocities (380 cm/s vs. 260 cm/s) compared to granite particles. The Savage number ($N_{sav}$) effectively captured fundamental flow-regime differences, with granite particles exhibiting values seven times lower than crystal beads (3.69 vs. 23.91, p < 0.001), indicating greater frictional energy dissipation relative to collisional energy transfer. The Bagnold number confirmed inertially dominated regimes ($N_{Bag}$ > 10⁶) with negligible viscous effects in both materials. These findings demonstrate that accessible material characterization using standard triaxial testing and dimensionless analysis can significantly improve landslide runout prediction accuracy, supporting evidence-based decision-making for sustainable territorial planning and community protection. This research supports the development of practical risk assessment methodologies implementable in resource-limited settings, promoting sustainable development through improved natural hazard management. Full article

Background: Developing reliable and cost-effective decellularization methods is critical for advancing tissue engineering and regenerative medicine, particularly in regions with limited access to specialized perfusion systems. Methods: This study standardized a gravity-assisted perfusion protocol for rat liver decellularization, designed to operate without pumps or pressurized equipment. Adult Wistar rat livers were processed through a gravity-driven vascular flushing method and compared with a conventional immersion-based protocol. The resulting scaffolds were evaluated by macroscopic inspection, histological staining (Masson’s trichrome), and residual DNA quantification. Results: The gravity-assisted perfusion method achieved more efficient cellular removal and superior preservation of extracellular matrix (ECM) integrity compared with immersion. Residual DNA levels were 3.7 ng/mg in perfused samples, 209.47 ng/mg in immersed samples, and 331.97 ng/mg in controls, confirming a statistically significant reduction (p < 0.05). Only the perfused group met the accepted threshold for effective decellularization (<50 ng/mg dry tissue). Histological analysis corroborated these findings, showing the absence of nuclei and the preservation of collagen architecture characteristic of a structurally intact ECM. Conclusions: This low-cost, reproducible, and technically simple system enables the generation of high-quality acellular hepatic scaffolds without mechanical pumps. Its accessibility and scalability make it suitable for laboratories with limited infrastructure and educational settings. Moreover, this gravity-assisted approach provides a foundation for future recellularization and preclinical studies aimed at developing bioengineered liver constructs for regenerative and transplant applications. Full article

Bacillus safensis strains have emerged as versatile microbial platforms for bioproduction, combining the benefits of probiotic utility and biocontrol. In this study, we describe the isolation and in-depth characterization of a previously unreported B. safensis strain, LG01. The genome of this strain comprises a circular chromosome encoding 13 secondary metabolite biosynthetic gene clusters, 144 carbohydrate-active enzymes, 2 antibiotic resistance loci, and 1 prophage region, indicative of strong antimicrobial and metabolic capacity. Its protein secretion systems support nutrient acquisition, colonization, quorum sensing, and antibiotic synthesis. Our phenotypic assays confirmed the antifungal and antibacterial activity, proteolytic and cellulolytic functions, and robust biofilm formation of the strain. By performing a comparative genomic analysis, we identified 78 strain-specific genes enriched in the bacteriocin immunity and sporulation pathways. Signals of positive selection in the membrane and transcriptional regulator genes further reflect the adaptive evolution underlying the strain’s ecological fitness. Together, these findings advance our understanding of the genomic features of B. safensis LG01 and highlight its promise as a candidate for biocontrol and probiotic applications. Full article