Search Results (7,998)

Obesity is a systemic metabolic disorder characterized by chronic low-grade inflammation and insulin resistance, with growing evidence indicating that the brain represents a primary and particularly vulnerable target organ. Beyond peripheral metabolic consequences, obesity induces region-specific structural, functional, and biochemical alterations within the central nervous system, contributing to cognitive impairment, dysregulated energy homeostasis, and increased susceptibility to neurodegenerative diseases. This narrative review examines key neurometabolic and neuroinflammatory mechanisms underlying obesity-related brain vulnerability, including downstream neuroinflammation, impaired insulin signaling, mitochondrial dysfunction, oxidative stress, blood–brain barrier disruption, and impaired brain clearance mechanisms. These processes preferentially affect frontal and limbic networks involved in executive control, reward processing, salience detection, and appetite regulation. Advanced neuroimaging has substantially refined our understanding of these mechanisms. Magnetic resonance spectroscopy provides unique in vivo insight into early neurometabolic alterations that may precede irreversible structural damage and is complemented by diffusion imaging, volumetric MRI, functional MRI, cerebral perfusion imaging, and positron emission tomography. Together, these complementary modalities reveal microstructural, network-level, structural, hemodynamic, and molecular alterations associated with obesity-related brain vulnerability and support the concept that such brain dysfunction is dynamic and potentially modifiable. Integrating neurometabolic and multimodal neuroimaging biomarkers with metabolic and clinical profiling may improve early risk stratification and guide preventive and therapeutic strategies aimed at preserving long-term brain health in obesity. Full article

Flow dynamics in strongly curved channels with submerged vegetation play a crucial role in riverine ecological processes and morphodynamics, yet the combined effects of sharp curvature and rigid submerged vegetation remain inadequately understood. This study presents a comprehensive experimental investigation into the influence of rigid submerged vegetation on the flow characteristics within a 180° strongly curved channel. Laboratory experiments were conducted in a U-shaped flume with varying vegetation configurations (fully vegetated, convex bank only, and concave bank only) and two vegetation heights (5 cm and 10 cm). The density of vegetation ϕ was 2.235%. All experimental configurations exhibited fully turbulent flow conditions (R_e > 60,000) and subcritical flow regimes (F_r < 1), ensuring gravitational dominance and absence of jet flow phenomena. An acoustic Doppler velocimeter (ADV) was employed to capture high-frequency, three-dimensional velocity data across five characteristic cross-sections (0°, 45°, 90°, 135°, 180°). Detailed analyses were performed on the longitudinal and transverse velocity distributions, cross-stream circulation, turbulent kinetic energy (TKE), power spectral density, turbulent bursting, and Reynolds stresses. The results demonstrate that submerged vegetation fundamentally alters the flow structure by increasing flow resistance, modifying the velocity inflection points, and reshaping turbulence characteristics. Vegetation height was found to delay the manifestation of curvature-induced effects, with taller vegetation shifting the maximum longitudinal velocity to the vegetation canopy top further downstream compared to shorter vegetation. The presence and distribution of vegetation significantly impacted secondary flow patterns, altering the direction of cross-stream circulation in fully vegetated regions. TKE peaked near the vegetation canopy, and its vertical distribution was strongly influenced by the bend, causing the maximum TKE to descend to the mid-canopy level. Spectral analysis revealed an altered energy cascade in vegetated regions and interfaces, with a steeper dissipation rate. Turbulent bursting events showed a more balanced contribution among quadrants with higher vegetation density. Furthermore, Reynolds stress analysis highlighted intensified momentum transport at the vegetation–non-vegetation interface, which was further amplified by the channel curvature, particularly when vegetation was located on the concave bank. These findings provide valuable insights into the complex hydrodynamics of vegetated meandering channels, contributing to improved river management, ecological restoration strategies, and predictive modeling. Full article

Antimicrobial resistance represents a critical challenge to global public health, driving the search for bioactive compounds in medicinal plants. The Fabaceae family stands out for its chemical richness and pharmacological properties; however, in the state of Tamaulipas, Mexico—an area of high diversity due to its location between the Nearctic and Neotropical regions—this flora remains largely unexplored. The objective of this review was to analyze the global scientific literature on the Fabaceae of Tamaulipas, integrating floristic records, phytochemistry, and antimicrobial activity. Of the 347 species recorded in the state, only 60 have phytochemical studies, and 43 have documented medicinal uses. The results show that extraction methods predominantly use polar solvents to isolate phenolic compounds, flavonoids, and alkaloids, which show efficacy against pathogens such as Staphylococcus aureus, Escherichia coli, and Candida albicans. Despite limited local ethnobotanical documentation, the potential demonstrated by these species in other regions positions Tamaulipas as a strategic reservoir. This review identifies research gaps and emphasizes the need for systematic studies that validate traditional uses and prioritize bioprospecting of the flora of northeastern Mexico for the development of new therapeutic alternatives. Full article

Loess subgrades are prone to significant strength reduction and deformation under cyclic traffic loads and moisture ingress. Permeable polyurethane polymer grouting has emerged as a promising non-excavation technique for rapid subgrade reinforcement. This study systematically investigated the fatigue behavior of polymer-grouted loess using laboratory fatigue tests and numerical simulations. A series of stress-controlled cyclic tests were conducted on grouted loess specimens under varying moisture contents and stress levels, revealing that fatigue life decreased with increasing moisture and stress levels, with a maximum life of 200,000 cycles achieved under optimal conditions. The failure process was categorized into three distinct stages, culminating in a “multiple-crack” mode, indicating improved stress distribution and ductility. Statistical analysis confirmed that fatigue life followed a two-parameter Weibull distribution, enabling the development of a probabilistic fatigue life prediction model. Furthermore, a 3D finite element model of the road structure was established in Abaqus and integrated with Fe-safe for fatigue life assessment. The results demonstrated that polymer grouting reduced subgrade stress by nearly one order of magnitude and increased fatigue life by approximately tenfold. The consistency between the simulation outcomes and experimentally derived fatigue equations underscores the reliability of the proposed numerical approach. This research provides a theoretical and practical foundation for the fatigue-resistant design and maintenance of loess subgrades reinforced with permeable polyurethane polymer grouting, contributing to the development of sustainable infrastructure in loess-rich regions. Full article

This study aims to investigate the tip resistance mechanism of open-ended steel pipe piles under partially plugged conditions by decomposing the load-sharing contribution of the ring zone and the internal soil core. A virtual static loading test was performed using the two-dimensional discrete element method (2D-DEM). Note that the findings of this study were obtained within the range of the 2D-DEM analysis conditions and do not intend to directly reproduce the three-dimensional arching mechanism or to establish equivalence between 2D and 3D responses. Quasi-static conditions were ensured by identifying loading parameters such that the energy residual remained ≤5% during driving, rest, and static loading phases, and the sensitivity criterion |Δq_b|/q_b ≤ 3% was satisfied when the loading rate was halved or doubled. The primary evaluation range of static loading was set to s/D = 0.1 (10% D), corresponding to the displacement criterion for confirming the tip resistance in the Japanese design specifications for highway bridges. For reference, the post-peak mechanism was additionally tracked up to s/D = 0.2 (20% D). Within a fixed evaluation window located immediately beneath the pile tip, high-contact-force (HCF) points were binarized using the threshold τ = μ + σ, and their occupancy ratio φ and normalized force intensity I* were calculated separately for the ring and core regions. A density-based contribution index (“K_{-density share}”) was defined by combining “strength × area” and normalizing by the geometric width. The results suggest that, for the sand conditions and particle-scale ratios examined (D/d_50 = 25–100), the ring zone tends to carry on the order of 85–90% of the tip resistance within the observed cases up to the ultimate state. Even at high plugging ratios (CRs), the internal soil core gradually increases its occupancy and intensity with settlement; however, high-contact-force struts beneath the ring remain active, and it is suggested that the ring-dominant load-transfer mechanism is generally preserved. In the post-peak plastic regime, the K_{-density share} remains around 60%, indicating that the internal core plays a secondary, confining role rather than becoming dominant. These findings suggest that the conventional plug/unplug classification based on PLR can be supplemented by a combined use of plugging ratio CR (a kinematic indicator) and the ring contribution index (K_{-density share}), potentially enabling a continuous interpretation of plugged and unplugged behaviors and contributing to the establishment of a design backbone for tip resistance evaluation. Calibration of design coefficients, scale regression, and mapping to practical indices such as N-values will be addressed in part II of this study. (Note: “Contribution” in this study refers to the HCF-based density contribution index K_{-density share}, not the reaction–force ratio.) Full article

The ecological network serves as a vital spatial strategy for addressing climate change, biodiversity loss, and habitat fragmentation. Addressing limitations in existing ecological network studies—such as strong subjectivity and insufficient accuracy in structural element identification, cross-regional integration, and resistance surface weighting—this research uses the Zhengzhou–Kaifeng–Luoyang region (ZKLR) as a case study. It introduces the self-organizing map (SOM) model to identify ecological sources and employs the XGBoost-SHAP model to optimize resistance surface weights, thereby reducing subjective weighting biases. Subsequently, the Linkage Mapper tool is utilized to construct the regional ecological network. The superiority of the SOM model for identifying ecological sources was confirmed by comparison with a traditional network based on morphological spatial pattern analysis (MSPA). Further integrating complex network topology theory, nodes attack the simulations-assessed network resilience and proposed optimization strategies. The results indicate the following: (1) The area of ecological sources identified by the SOM model is three times that of the MSPA model; (2) SHAP feature importance analysis revealed that elevation (DEM) exerted the greatest influence on the composite resistance surface, contributing over 40%, followed by land use and slope, with each contributing approximately 15%. High-resistance areas were primarily distributed in western and central mountainous regions and built-up urban areas, while low-resistance areas were concentrated in the central and eastern plains; (3) topological analysis indicates that the integrated ecological network (IEN) exhibits superior robustness compared to the structural ecological network (SEN). The edge-adding strategy generated 22 additional ecological corridors, significantly enhancing the overall resilience of the integrated ecological network; and (4) based on ecological network construction and optimization results, a territorial spatial protection strategy of “one belt, two cores, two zones, and three corridors” is proposed. This study provides a novel methodological framework for ecological network construction, with findings offering reference for ecological conservation and spatial planning in the ZKLR and similar areas. Full article

Aspergillus fumigatus, a saprophytic fungus, causes aspergillosis, primarily affecting the immunocompromised. The efficacy of triazole antifungals is compromised by resistance that has developed both clinically and environmentally. Widespread agricultural use of similar triazole fungicides selects for resistant genotypes, leading to potential food contamination and compromising treatment. This study assessed the presence of azole-resistant A. fumigatus in minimally processed food items commonly consumed in Brazil. A total of 25 commercial samples, including black pepper, yerba mate, and green coffee beans, were collected from different regions. Forty-two A. fumigatus isolates were recovered and screened for susceptibility to agricultural and clinical triazoles by determining EC₅₀ values for tebuconazole (0.04–0.7 µg/mL), itraconazole (0.06–0.5 µg/mL), and voriconazole (0.07–0.15 µg/mL). Sequence analysis of the CYP51A gene revealed the presence of M172V mutation, none of which are associated with resistance. Microsatellite genotyping indicated high genotypic diversity and genetic relatedness among isolates from different food sources. Although no azole-resistant phenotypes were identified, the consistent recovery of A. fumigatus from products not directly exposed to azole fungicides highlights the need for continued surveillance. Agricultural environments remain critical hotspots for the emergence and dissemination of resistance, reinforcing the importance of integrated One Health strategies in antifungal resistance monitoring. Full article

Background: Libya, a conflict-affected North African country, has a fragile health system and poor surveillance, leaving it largely underrepresented in global estimates. Earlier Libyan reviews were descriptive, lacking breakpoint standardization, isolate-level pooling, or AMR-attributable mortality and DALY estimates. To our knowledge, this study represents the first comprehensive report that integrates phenotypic and genotypic data to estimate deaths and DALYs attributable to AMR-induced mortality and morbidity, describe spatiotemporal patterns, and model future trajectories. Methods: We performed a meta-analysis according to the PRISMA 2020 guideline of Libyan studies reporting phenotypic or genotypic resistance among clinical bacterial isolates (1970–2024), combined with microbiology records from hospitals and national surveillance systems (preregistered in PROSPERO ID: CRD420251066018). Susceptibility results were standardized to CLSI/EUCAST and deduplicated using WHO GLASS first-isolate rules. We used random-effects meta-regression to estimate pooled resistance, and the counterfactual approach of Global Burden of Disease (GBD) was applied to estimate AMR-attributable DALYs. Molecular data on resistance genes, sequence types, and tuberculosis mutations were systematically collected. Results: We included 62 eligible studies together with national and facility-level surveillance datasets, providing isolate-level susceptibility data for 31,439 clinical isolates from Libya. In 2024, we estimated 2183 deaths (95% UI 1752–2614) attributable to AMR, representing 9.7% (95% UI 7.8–11.6) of total deaths with a mortality rate of 15.2 per 100,000 (12.2–18.2). DALYs attributable to AMR increased from 14,628 (95% UI 11,702–17,554) in 1970 to 96,715 (95% UI 77,372–116,058). The highest pooled resistance involved carbapenem-resistant/MDR A. baumannii, third-generation cephalosporin- and fluoroquinolone-resistant Enterobacterales, and carbapenem-resistant P. aeruginosa. Molecular data showed widespread ESBLs, OXA-/NDM-type carbapenemases, plasmid-mediated colistin resistance, high-risk E. coli ST131 and K. pneumoniae ST147 lineages, and canonical drug-resistant M. tuberculosis mutations. Conclusions: Combined with global and regional evidence, our findings suggest a high and increasing burden of AMR in Libya. These findings emphasize the need for rapid expansion of data collection systems, GLASS-aligned surveillance, diagnostic capacities, and infection control measures. Full article

Polyester fibers are extensively used in textiles, packaging, and industrial applications due to their durability and excellent mechanical properties. However, high-crystallinity polyester fibers represent a major challenge in plastic waste management due to their resistance to biodegradation. This study evaluated the biodegradation potential of environmental Bacillus isolates, obtained from mold-contaminated black bean plastic bags, toward polyethylene terephthalate (PET) and industrial-grade polyester fibers under mesophilic conditions. Among thirteen isolates, five (Bacillus altitudinis N5, Bacillus subtilis N6, and others) exhibited measurable degradation within 30 days, with mass losses up to 5–6% and corresponding rate constants of 0.04–0.05 day⁻¹. A combination of complementary characterization techniques, including mass loss analysis, scanning electron microscopy (SEM), gel permeation chromatography (GPC), and gas chromatography/mass spectrometry (GC/MS), together with Fourier-transform infrared spectroscopy (FTIR), thermogravimetric/differential scanning calorimetry (TGA/DSC), and water contact angle (WCA) analysis, was employed to evaluate the biodegradation behavior of polyester fibers. Cross-analysis of mass loss, surface morphology, molecular weight reduction, and degradation products suggests a surface erosion-dominated degradation process, accompanied by ester-bond hydrolysis and preferential degradation of amorphous regions. FTIR, TGA/DSC, and WCA analyses further reflected chemical, thermal, and surface property changes induced by biodegradation rather than directly defining the degradation mechanism. The findings highlight the capacity of mesophilic Bacillus species to partially depolymerize polyester fibers under mild environmental conditions, providing strain resources and mechanistic insight for developing low-energy bioprocesses for polyester fiber waste management. Full article

Strengthening their supply chain resilience constitutes a strategic priority for Chinese enterprises to respond to evolving globalization patterns and sustain long-term competitiveness in an increasingly sustainability-oriented market. This research systematically measures enterprise supply chain resilience by analyzing panel data from Chinese listed firms (2010–2022) through the tri-dimensional constructs of resistance capacity, recovery resilience, and adaptive creativity. Regression analyses demonstrate that digital transformation significantly improves enterprise supply chain resilience, exhibiting dual-threshold characteristics in nonlinear relationships. Mediation tests reveal that information sharing and resource integration capabilities serve as the critical transmission channels. Digital transformation demonstrates strong predictive validity for both the resistance capacity and adaptive creativity of supply chains. The seemingly paradoxical findings on enterprise operational efficiency highlight the need for a more layered and dynamic understanding of its underlying mechanisms. The positive impact of digital transformation on supply chain resilience demonstrates heterogeneity across state-owned versus non-state-owned enterprises, regions, and industry types. The findings offer actionable insights for orchestrating digital transformation initiatives and designing tiered supply chain resilience frameworks that support enterprises’ sustainability goals. Full article

Hydrogen permeation parameters of PA12 were obtained through high-pressure hydrogen permeation experiments conducted under various temperature and pressure conditions. The temperature-dependent mechanism governing the hydrogen permeation behavior of PA12 was further examined using dynamic mechanical analysis (DMA). A multi-field coupled numerical model was established and validated against the experimental results. Based on the validated numerical approach, the hydrogen permeation behavior of a type IV hydrogen storage vessel with local reinforcement was investigated. The results show that both temperature and pressure have a significant influence on the hydrogen permeation performance of PA12. When the temperature is below the glass transition temperature ($\mathit{Tg}$) of PA12 (48.34 °C), the diffusion coefficient remains low, whereas temperatures above the $\mathit{Tg}$ led to a marked increase in the diffusion coefficient. In addition, the local reinforcement patch effectively prolongs the time required to reach steady-state permeation, reduces the hydrogen permeation flux before and after steady state, and enhances the overall resistance to hydrogen permeation of the type IV vessel. As the diffusion coefficient of the liner material increases, the hydrogen diffusion rate increases substantially, leading to greater hydrogen accumulation in the dome region and higher permeation levels both before and after steady state. These findings provide theoretical guidance and design references for optimizing the hydrogen-resistant performance of type IV hydrogen storage vessels. Full article

Based on panel data from China’s 31 provinces and municipalities covering 2011–2023, this study constructs a multidimensional evaluation system for digital economic development and agricultural industrial chain resilience within the Technology-Organization-Environment (TOE) framework. It systematically examines the impact of the digital economy on agricultural industrial chain resilience and its sub-dimensions, while introducing green finance as a moderating variable. The findings reveal: First, the development of the digital economy significantly enhances the resilience of the agricultural industrial chain. This conclusion withstands multiple robustness tests, and the impact of the digital economy on the three dimensions of agricultural industrial chain resilience (resistance, recovery, and reconstruction) varies, particularly exhibiting a negative effect on reconstruction. Second, the enabling effect of the digital economy on agricultural industrial chain resilience shows a significant spatial gradient. Regionally, resilience is ranked as “Production-Sales Balance Zones > Main Sales Zones > Main Production Zones” within grain functional zones, and “Northeast > West > East > Central” across China’s four major economic regions. Third, green finance development exerts a negative moderating effect on the pathway through which the digital economy enhances agricultural supply chain resilience, higher green finance levels weaken the marginal improvement effect of the digital economy. This study fills research gaps regarding the multidimensional impact of digital economic development on agricultural industrial chain resilience and empirically supplements the lack of evidence on the negative moderating mechanism of green finance and its sub-dimensions, providing policy tools for agricultural modernization and resilience governance. Full article

To address the freeze-thaw (F-T) durability of concrete structures in severely cold plateau regions, this study investigates recycled coarse aggregate concrete (RCAC) by designing mixtures with varying replacement ratios of recycled brick aggregate (RBA). Rapid freeze-thaw cycling tests are conducted in combination with macro- and microscale analytical techniques to systematically elucidate the frost resistance and damage mechanisms of mixed recycled coarse aggregate concrete. When the RBA content is 50%, the concrete demonstrates relatively better frost resistance within the mixed recycled aggregate system. This is evidenced by the lowest mass loss rate coupled with the highest retention ratios for both the relative dynamic elastic modulus (RDEM) and the compressive strength. Micro-analysis indicates that an appropriate amount of RBA can optimize the pore structure, exerting a “micro air-cushion” buffering effect. Blending RBA with recycled concrete aggregate (RCA) may create functional complementarity between pores and the skeleton, effectively delaying freeze–thaw damage. A GM (1,1) damage prediction model based on gray system theory is established, which demonstrates high accuracy (R² > 0.92). This study provides a reliable theoretical basis and a predictive tool for the durability design and service life assessment of mixed recycled coarse aggregate concrete engineering in severely cold regions. Full article

Unsteady flow-induced pressure fluctuations and the consequent dynamic stresses in pump-turbines are critical determinants of their operational reliability and fatigue resistance. This investigation systematically examines the spatiotemporal propagation of Rotor–Stator Interaction (RSI)-induced pressure pulsations and evaluates the corresponding dynamic stress mechanisms based on a phase-resolved fluid–structure interaction strategy. The results reveal a significant hydrodynamic duality: RSI pressure waves manifest as convective traveling waves on the pressure side but as modal standing waves on the suction side. Crucially, a severe spanwise phase mismatch is identified between the hub and shroud streamlines, which induces a periodic hydrodynamic torsional moment on the blade. Due to the rigid constraint at the blade–crown junction, this torsional tendency is restricted, resulting in high-amplitude constrained tensile stresses at the root. This explains why the stress concentration at the crown inlet is significantly higher than in other regions. Additionally, the stress spectrum shows strong load dependence, characterized by low-frequency modulations on the suction side under high-load conditions. Full article

A knowledge of the process–structure–property correlation and underlying deformation mechanisms of material under a coupled electro-thermal–mechanical field is crucial for developing novel electrically assisted forming techniques. In this work, numerical simulation and experimental analyses were carried out to study the non-uniform deformation behaviors and microstructure evolution of Ti₂AlNb-based alloy stiffened panels in different characteristic deformation regions during electrically assisted press bending (EAPB). The quantitative relationships between electro-thermal–mechanical routes, microstructural features, and mechanical properties of EAPBed stiffened panels were initially established, and the underlying mechanisms of electrically induced phase transformation and morphological transformation were unveiled. Results show that the temperature of the panel first increases then deceases with forming time in most regions, but it increases monotonically and reaches its peak value of 720.1 °C in the web region close to the central transverse rib. The higher accumulated strain and precipitation of the acicular O phase at mild temperature leads to strengthening of the longitudinal ribs at near blank holder regions, resulting in an ideal microstructure of 3~4% blocky α₂ phase + a dual-scale O structure in a B2 matrix with a maximal hardness of 389.4 ± 7.2 HV_0.3. While the dissolution of the α₂ phase and the spheroidization and coarsening of the O phase bring about softening (up to 9.29%) of the lateral ribs and web near the center region, the differentiated evolution of microstructure and the mechanical property in EAPB results in better deformation coordination and resistance to wrinkling and thickness variation in the rib–web structure. The present work will provide valuable references for achieving shape-performance coordinated manufacturing of Ti₂AlNb-based stiffened panels. Full article