Search Results (4,469)

Background/Objectives: High-voltage, low-current electric shocks inflict superficial second-degree burns on the skin, accompanied by a vicious cycle of excessive oxidative stress and inflammation. As efficient treatment of such electrical burns remains a clinical challenge, we explored the efficacy of an injectable thermosensitive chitosan hydrogel engineered with an antioxidant agent (astaxanthin) and an anti-inflammatory agent (ibuprofen) for the treatment of high-voltage, low-current electrical burn injuries. Methods: The proposed CS/AST/IBU hydrogel was prepared and its thermosensitivity was characterized. Subsequently, the hydrogel was injected into the wounds of male Sprague–Dawley (SD) rats subjected to electrical burn injury (20 kV, 3 mA). Finally, a series of experiments were performed to elucidate the dynamics of wound healing and the mechanisms by which the hydrogel promotes wound repair. Results: The injectable hydrogel, through its thermally responsive gelation effect at 37 °C, adapts to the complex irregularities of the wound surface. This facilitates the release of astaxanthin and ibuprofen throughout the wound, which collectively diminish the formation of reactive oxygen species and MDA. Furthermore, it enhances the synthesis of endogenous antioxidants such as SOD, CAT, and GSH; encourages collagen deposition; stimulates the development of dermal appendages; and fosters neovascularization. It interrupts the deleterious cycle of oxidative stress and inflammation mediated by the NF-κB signaling pathway, thereby suppressing the expression of pro-inflammatory markers such as TNF-α, CD11b, and IL-1β while upregulating CD163, an anti-inflammatory receptor. Conclusions: The use of this multipronged, contour-adaptive hydrogel represents an effective strategy for complex wound management and demonstrates broad therapeutic potential for superficial second-degree electrical burns caused by high-voltage, low-current discharge. Full article

Shore power (SP) is a critical solution for decarbonizing maritime transport, yet its adoption is hindered by the “high investment, low utilization” paradox, driven by high initial costs and misaligned incentives between ports and ships. While government subsidies are essential, traditional static policy designs often fail to adapt to the complex, non-linear dynamics of technology diffusion. To address this, the study proposes a dynamic evaluation framework combining System Dynamics (SD) with Evolutionary Game Theory (EGT), embedding a Rolling Horizon Optimization algorithm. Using Shanghai Port as a case study, simulation results demonstrate that optimal subsidies are highly state-dependent. Specifically, effective promotion requires prioritizing ship-side incentives during the early start-up phase, followed by facilities subsidies supporting the coordinated evolution of both ships and berths, and finally a market-driven exit. Furthermore, the proposed dynamic strategy demonstrates superior robustness against oil price volatility and demand shocks compared to static policies, while strictly complying with fiscal budget caps. This framework provides a foundation for the adaptive management of green port infrastructure, facilitating the advancement of energy-saving and environmental protection initiatives within the maritime industry. Additionally, it contributes to the forecasting and evaluation of the policy outcomes of green technology adoption. Full article

As climate-related disasters increase globally, research on practical corporate measures to address climate change risks is essential for ensuring business security and long-term economic sustainability. This study investigates the impact of climate risk on firm value with a focus on the moderating role of supply chain strategic choice. Our findings show that firms in cities with greater climate risks are associated with lower firm value. We study influence mechanisms and find that increased operational disruption risk, reputational damage, and strengthened local environmental regulations are significant influence mechanisms. From the perspective of supply chain strategic choice, enhancing geographic diversification and local supplier diversification, increasing supply security reserves, and advancing supply chain digitalization can significantly mitigate the negative impact of climate risk on firm value, possibly suggesting that firms can respond to climate risks by adapting their supply chain strategies. Heterogeneity analysis shows that climate risk has greater effects in regions characterized by weak institutional capacity for climate risk response and high public awareness of climate shocks, as well as among non-state-owned firms. Additional analysis indicates that climate risk accelerates corporate efforts to improve ESG performance, thereby reinforcing their green and sustainable development. Overall, our findings provide an alternative perspective on the risk-management benefits of supply chain strategies, suggesting that supply chain strategies can be regarded as a response to climate change-related risks for corporations. Full article

As a populous country with limited per capita land area, China has implemented the strictest land use regulation to ensure food security. Yet quantitative assessments of how it shapes land use change and the subsequent economic impacts remain insufficient. Land use directly affects land supply for industry and services, thereby impacting local fiscal and tax revenues. Meanwhile, land transfer income serves as a major off-budget revenue source for local governments, with county fiscal capacity laying the foundation for national economic development and public welfare. Therefore, this study integrates county-level statistics with remotely sensed land use data and applies an Intensity Difference-in-Differences (Intensity DID) design to identify policy impacts. Specifically, it examines the effects of land use regulation on county governments’ land transfer activities, land use efficiency, as well as fiscal revenue and public service provision. Empirical results show that tighter land use regulation constrains the new supply of construction land by limiting cultivated land conversion. In response, local governments modify floor area ratios (FARs) and shorten construction cycles, which is conducive to improving land use efficiency. Nevertheless, the policy reduces the land transfer income, tax revenue, and general public budget revenue of county governments, weakening public service provision. Heterogeneity analysis indicates that major grain-producing counties are more severely affected by negative policy shocks than non-major ones. This study provides empirical evidence for optimizing the land use regulation system and offers policy implications for coordinating food security and balanced regional development through horizontal interest compensation in major grain-producing regions. Full article

This paper reviews the enhancement mechanisms of fatigue performance in titanium alloys processed by laser shock peening (LSP). Because of the redistribution of residual stress and micro-crack and pore behavior, micro–nanostructure evolution and surface roughness effect are systematically discussed. LSP induces beneficial compressive residual stresses at the surface, effectively suppressing crack initiation and propagation. Notably, the nanostructures induced by this process—including nanotwins, dislocations, stacking faults, and nanocrystals—collectively enhance the material’s mechanical hardness, strength, and fatigue resistance. Furthermore, LSP reduces porosity, alters pore morphology and alters crack initiation sites, thereby increasing the crack propagation threshold. However, the influence of LSP on material toughness remains a subject of debate. The insights provided herein offer valuable theoretical guidance for the development of high-performance titanium alloys and further optimization of LSP technology. Full article

The assessment of climate variability impacts on crop production and price varies by what factors studies consider, including annuals and perennials. Unlike annual crops, climate impacts on perennial crops like coconuts require a multiple-year assessment. Although previous studies have examined climate effects on coconut production, there is a critical gap in understanding multiple-year impacts of climate variability on coconut production and price. Therefore, this paper aims to fill this gap by assessing the extent to which climate variability affects coconut production and prices in Sri Lanka, the fourth largest coconut producer in the world. For this purpose, we analyzed rainfall, temperature, average drought months, coconut production, coconut cultivation area, and coconut retail price from 2010 to 2022. We then created and administered five regression models to illustrate the impact of climate variables for a single year and multiple years on coconut production, yield, and price. The results indicate that rainfall in the previous year is the most critical determinant for production (p = 0.014) and yield (p = 0.032), while drought intensity and temperature shocks show delayed negative effects on production. Lagged temperature shocks and supply shortages significantly increased nominal coconut retail prices. A temperature increase by 1 °C in the previous year raised prices by approximately LKR 36 per nut. After adjusting for inflation, only temperature (p = 0.002) effects was found significant, indicating that climate-induced supply constraints dominate real price changes. Our three-year analysis showed that drought conditions, together with rainfall and temperature variability, reduced production with a delayed effect (p = 0.026). These findings highlight the importance of incorporating multiple-year climate impacts into adaptation and price stabilization policies for coconut and other perennial crops. Full article

Traveling wave ultrasonic motors (TWUMs) are critical components in precision systems, yet their performance is susceptible to degradation under dynamic disturbances in harsh operating environments. This paper presents a monolithic U-shaped rotor designed to intrinsically achieve quasi-zero stiffness (QZS). Unlike conventional QZS systems that rely on assembling discrete positive and negative stiffness elements, the proposed design generates the target mechanical characteristic through the tailored nonlinear response of a unified U-shaped structure, thereby improving preload stability. Through exploring the critical parameters of the rotor cross-section, the finite element method (FEM) is employed to optimize the geometry configuration and characterize the mechanical performances. The simulation results show the QZS behavior demonstrating a stable force plateau of 320 ± 10 N across a 0.7 mm displacement range. A maximum von Mises stress of 788 MPa is obtained, well within the material’s safety margin, thereby ensuring the structural integrity. Experimental tests validate the effectiveness of the proposed design. This compact, monolithic U-shaped rotor provides a robust and reliable QZS solution, demonstrating significant potential for enhancing the stability of TWUMs in applications prone to harsh environments such as wide-range temperature fluctuations, thermal cycling conditions, and shock environments. Full article

The increasing prevalence of antimicrobial resistance, especially in methicillin-resistant Staphylococcus aureus (MRSA), underscores the need for alternative therapies from natural sources. This study investigated the chemical composition, antibacterial activity, and gene expression modulation of Melaleuca cajuputi essential oils. Gas chromatography–mass spectrometry (GC-MS) identified 91 compounds, with naphthalene (23.90%), guaiol (12.92%), caryophyllene oxide (9.69%), D-limonene 98% (8.59%), and gamma terpinene (7.54%) among the most abundant. In Silico molecular docking against MRSA virulence proteins revealed that alloaromadendrene had the strongest binding to toxic shock syndrome toxin-1 (TSST-1) (−7.948 kcal/mol), suggesting high inhibitory potential, while cyclohexane showed weak binding with staphylococcal enterotoxin A (SEA) (−3.532 kcal/mol). Antibacterial assays demonstrated concentration-dependent inhibition, with the zones ranging from 6.33 ± 0.33 mm to 16.67 ± 0.88 mm. MIC and MBC values ranged from 1.56 to 12.5% and 3.13 to 25%, respectively, with most isolates showing bactericidal effects (MBC/MIC ≤ 2). Gene expression analysis of MRSA isolate 4 indicated that sea was moderately upregulated (FC = 1.44), while sec remained unchanged (FC = 1.02). In contrast, fnbA (FC = 0.72), seb (FC = 0.33), and mecA (FC = 0.23) genes were downregulated, and the tsst-1 gene (FC = 0.05) was nearly silent. These findings highlight M. cajuputi essential oils as a promising candidate with both antibacterial efficacy and regulatory effects on MRSA virulence genes. Full article

Ram semen is highly susceptible to cold shock, which induces irreversible damage to the integrity and fluidity of membranes. Chilled semen is commonly used within 24 h of collection. However, while its storage at 5 °C extends semen lifespan, it is often accompanied by quality deterioration due to accumulation of reactive oxygen species (ROS). This study evaluated the potential of crocin, a carotenoid with antioxidant properties, to improve the quality of chilled ram semen stored at 5 °C for up to three days in a soybean lecithin–based extender supplemented with two crocin concentrations (0.5 and 1 mM). Sperm motility, viability, glutathione levels, the expression of proteins involved in the heat stress response (HSR), and apoptosis were assessed at 24 h intervals. Crocin preserved motility (up to Day 1), viability (up to Day 2,) and kinematic parameters (up to Day 3). In addition, crocin enhanced intracellular glutathione and Hsp70 levels and inhibited apoptotic levels dose-dependently, indicating the antioxidant and cytoprotective role of crocin. Despite 0.5 mM being effective up to Day 1, 1 mM crocin augmented antioxidant capacity, modulated stress response mechanisms, and preserved sperm quality during chilled storage up to Day 3, highlighting its potential as a valuable additive of ram semen extenders. Full article

Ultrasonic Impact Treatment (UIT), a prevalent surface-strengthening technology for welded structures, combines mechanical shock and ultrasonic vibration to induce plastic deformation and beneficial residual compressive stress at weld toes, effectively enhancing welded joint fatigue performance. This study adopts a full-process numerical simulation approach, integrating the finite element software ABAQUS and FE-SAFE fatigue-life prediction platform to investigate QSTE700TM high-strength automotive steel butt joints. Considering welding-induced initial residual stress, ABAQUS simulates the welding and subsequent UIT processes; explicit dynamic analysis reveals residual stress evolution, with pre- and post-UIT stress-distribution comparisons. The post-UIT residual stress field is input into a static tensile model to obtain load-stress distributions, which are then imported into FE-SAFE with S-N curves for fatigue-life prediction. Simulation results align well with experimental data: UIT improves the fatigue limit of welded specimens by 31.3% and unwelded ones by 42.9%. Additionally, optical and scanning electron microscopes observe fatigue fracture morphologies to further clarify UIT’s fatigue-enhancement mechanism. Full article

This study investigates the mechanical performance and blast resistance of high-performance aramid, carbon, and ultra-high molecular weight polyethylene (UHMWPE) fiber fabrics, responding to the need for lightweight and flexible materials in anti-explosion containers for aviation and critical infrastructure. The experimental methodology integrated quasi-static and dynamic tensile tests to characterize the strain-rate effect, followed by near-field air blast tests on both single-material and hybrid multi-ply fabric specimens to analyze their dynamic response, failure modes, and overpressure attenuation. Key findings revealed that carbon fabric exhibited high stiffness but was strain-rate insensitive and susceptible to brittle perforation failure, whereas aramid and UHMWPE fabrics demonstrated strain-rate sensitivity, with UHMWPE showing superior ductility and energy absorption. The hybrid multi-ply configuration (A-C-U sequence) achieved the least amount of failure, effectively utilizing the wave impedance of aramid fabric for initial shock reflection, high stiffness of carbon fabric for stress homogenization, and plasticity of UHMWPE fabric for energy dissipation. Additionally, all fabrics attenuated peak overpressure by over 80%, with enhancement observed for increased thickness. The study concludes that the strategic layering of different fabrics creates a synergistic effect, mitigating the weaknesses of individual fabrics and establishing an effective design paradigm for advanced blast-resistant structures, further enhancing the protective performance. Full article

Background: Posttraumatic stress disorder (PTSD) is a mental illness in which central stress-regulating regions, including locus coeruleus (LC) and paraventricular nucleus of hypothalamus (PVN), play key roles. Clonidine, a central sympatholytic drug, can inhibit LC activity and reduce PTSD-related symptoms, suggesting noradrenergic involvement. Glia-driven immune mechanisms may link LC activity to PVN responses. Since TRPA1 ion channel is implicated in both neuroinflammation and stress adaptation, we aimed to determine whether its presence modulates the function of brain structures contributing to PTSD-related alteration in central stress adaptation. Methods: Foot shock PTSD model was applied to Trpa1 wild-type (WT) and knockout (KO) mice, and outcomes were assessed four weeks later. Immunohistochemistry was used to evaluate tyrosine hydroxylase (TH) levels in the LC and glial activation in the PVN. Behavioral effects of clonidine and circulating corticosterone levels were also examined. Results: Stress increased LC/TH immunoreactivity and PVN glial activation. Trpa1 deletion exaggerated LC/TH responses but reduced PVN astrocyte activation. Clonidine increased freezing and decreased jumping (a hyperarousal marker). KO mice showed enhanced jumping and did not respond to clonidine. Corticosterone levels remained unchanged. Conclusions: TRPA1 may support stress adaptation in PTSD by regulating LC noradrenergic output and PVN neuroinflammation, independently of α₂-adrenergic signaling. Full article

We argue that turbulent irreversibility is best explained as an asymptotic feature of a singular inviscid limit—a reclassification of admissible entities and balances at $\nu \to 0$—rather than as a mere residual effect of molecular viscosity. Tracing a conceptual line from Euler and Kármán–Howarth to Onsager, Duchon–Robert, Kato/Prandtl, and modern convex integration results, we show that the limit theory reclassifies the admissible entities: from smooth Euler fields (energy conserving) to rough weak solutions equipped with a positive defect measure in the energy balance. The constant inter-scale process (energy flux) observed at high-Reynolds number therefore persists at $\nu =0$ as a structural feature of the limit ontology. We articulate three selection principles—the local energy inequality, the exact third-order law, and scale-locality—as ontological constraints that reconcile mathematical non-uniqueness with physical uniqueness. A brief conceptual history clarifies how the arrow of time in turbulence emerged through successive shifts of entities and invariants, and a comparison with other singular limit explanations (Boltzmannian irreversibility, shocks, renormalization) situates the account within general foundations of physics. Methodologically, we recast LES/closures as asymptotic mediators validated by flux plateaus and viscosity-free diagnostics, not microscopic subgrid fidelity. Full article

Assessing urban resilience under compound shocks requires observable and comparable process evidence that can inform resilient land governance and cross-jurisdiction planning. Using China’s Pilot Free Trade Zones (PFTZs) as a staged institutional setting, this research examines whether institutional exposure is associated with deviation–recovery trajectories of urban activity during the 2020 COVID-19 shock and whether these associations propagate through spatial spillovers with an identifiable scale profile. Institutional exposure is operationalized by the prefecture-level cities actually covered by PFTZ functional areas. With harmonized administrative boundaries, we construct an annual city-level VIIRS nighttime light (NTL) series for 2013–2024 and treat NTL as an activity-change signal rather than a direct proxy for output. We trace shock deviation in 2020 and subsequent recovery via staged differencing. Spatial interaction frictions are represented by least-cost path distance (LCPD) derived from a multi-source cost surface, which is used to build a gravity-based spatial weight matrix. Estimation relies on the Spatial Durbin Model (SDM), with LeSage–Pace impact decomposition to distinguish direct and spillover effects, complemented by distance-threshold diagnostics to map attenuation patterns. Results indicate persistent clustering within the PFTZ-related urban system. The shock year is characterized by compressed connectivity and fragmented brightening, whereas recovery proceeds in a layered manner with earlier core repair, partial corridor reconnection, and weaker adjustment at the periphery. Spatial dependence in activity change is statistically significant. Associations linked to institutional exposure are realized primarily locally, while structural and scale conditions more readily operate through spatial externalities. Spillovers are most detectable at meso-scales and attenuate gradually across distance thresholds. Overall, the integrated earth-observation and spatial-econometric framework provides replicable geospatial evidence to support resilient land governance and regional coordination under common shocks. Full article

Against the backdrop of global economic volatility, environmental pressures, and intensifying industry competition, tourism resilience has become a critical indicator for assessing the capacity of tourism systems to withstand external shocks and achieve sustainable development. As an important engine of high-quality economic growth, the digital economy provides new momentum for strengthening tourism economic resilience. Existing literature predominantly focuses on the direct impacts of the digital economy, with insufficient exploration of its mediating pathways and spatial effects. Based on panel data from 11 provinces in China’s Yangtze River Basin from 2011 to 2023, this study constructs comprehensive evaluation index systems for the digital economy and tourism economic resilience. A mediating effect model and a Spatial Durbin Model are employed to systematically examines the impact mechanisms and spatial spillover effects of the digital economy on tourism resilience. The results show that the digital economy significantly enhances tourism economic resilience, primarily by fostering openness and technological innovation. Heterogeneity analysis indicates that this effect is more pronounced in provinces located in the upper and lower reaches of the Yangtze River Basin. Spatial analysis further reveals a significant positive local effect, accompanied by a negative spillover—or ‘siphon’—effect on neighboring provinces. Building upon the verification of the fundamental relationship, this study further extends the theoretical analytical framework of tourism resilience from the dimensions of mechanism decomposition and spatial effects. It thereby offers new empirical evidence and policy insights for fostering regional tourism resilience in the era of the digital economy. Full article