Search Results (9,765)

For geotechnical structures with a strict control requirement of deformation, the high modulus and non-linear attenuation characteristics of the surrounding soil under small-strain conditions cannot be ignored during performance evaluation; the HSS constitutive model offers significant advantages over conventional approaches (e.g., Mohr–Coulomb) to describe the above soil behaviors. In this study, the theoretical framework of the HSS model, i.e., the yield function, hardening laws, and flow rule, is first elucidated. Subsequently, it is numerically implemented into the finite element software FssiCAS. The reliability of the FssiCAS software (Version 3.5) incorporating the HSS model is validated through a triaxial test and a physical test involving the horizontal loading of the monopile. Finally, taking the four-monopile jacket foundation of an offshore wind turbine (OWT) in Lianjiang County, China, as a representative, the HSS model is adopted to describe the mechanical behaviors of a seabed foundation. The horizontal bearing characteristics of the jacket foundation–seabed system under multi-angle horizontal loading are investigated, and the influence of the horizontal loading angle on the horizontal bearing capacity, jacket displacement, and seabed deformation is quantitatively elucidated. The results indicate that (1) the horizontal bearing capacity of the jacket is minimal when horizontal loading is along the diagonal of the four piles, representing the most severe loading case, and therefore, the horizontal bearing capacity of the jacket foundation–seabed system should be evaluated based on this case; and (2) the FE software FssiCAS has good reliability when dealing with pile–soil interaction problems involving complex geometries and complex mechanical behaviors of seabed soils. This study could provide technical support and an analysis platform for the design of jacket foundations for complex marine structures, such as OWTs. Full article

Populus euphratica (P. euphratica) is a dominant tree species in the arid and semi-arid regions along the main stem of the Tarim River. This study aims to explore the response of microbial communities in the rhizosphere soil of P. euphratica to varying groundwater depths (GWD) and to elucidate the ecological functions of key microbial groups in drought resistance. We established three groundwater depth levels (3.8 m, 5.4 m, and 7.35 m) and employed metagenomic sequencing technology to systematically analyze the topological characteristics of functional microbial community networks, as well as the types and quantities of key microbial groups in the rhizosphere soil of P. euphratica under different GWD conditions. The results indicate that compared to GWDs of 3.8 m and 7.35 m, the average degree and graph density of microbial communities in the rhizosphere soil of P. euphratica at a depth of 5.4 m are the highest. This suggests that at a GWD of 5.4 m, the connectivity and stability of the microbial network structure in the rhizosphere soil of P. euphratica are significantly enhanced. Analysis of the Zi-Pi values within the microbial network structure reveals that, compared to GWDs of 3.8 m and 7.35 m, a depth of 5.4 m supports the greatest variety and quantity of key microbial species in the rhizosphere soil of P. euphratica. The four connecting nodes identified are Actinophytocola, Haladaptatus, Devosia and Pseudonocardia. Spearman correlation analysis demonstrates that the relative abundance of the key bacterial genus Mesorhizobium in the rhizosphere soil of P. euphratica at different GWD is significantly positively correlated with soil catalase (CAT) and urease (UE) activity. Furthermore, the relative abundance of the key bacterial genus Pseudonocardia shows a significant positive correlation with soil total nitrogen (TN) and ammonium nitrogen (NH₄⁺-N) (p < 0.05). The relative abundance of the key bacterial genus Devosia exhibits a highly significant positive correlation with soil water content (SWC) (p < 0.01) and a significant negative correlation with soil NH₄⁺-N (p < 0.05). Additionally, the relative abundance of Devosia is significantly positively correlated with soil CAT (p < 0.05). This study provides a theoretical foundation for the conservation of desert poplar forests in arid regions and for the identification and cultivation of specific key microbial communities in the rhizosphere soil of P. euphratica. Full article

Phytoplankton communities are crucial for sustaining the high biodiversity and productivity of estuarine ecosystems, yet these regions are increasingly impacted by anthropogenic activities. To elucidate the impacts of anthropogenic pressures, this study characterized the seasonal dynamics of the phytoplankton community in the outer Yangtze River Estuary using an environmental DNA (eDNA) metabarcoding approach. We identified 279 and 306 phytoplankton genera in summer and autumn, respectively. Community composition differed more between seasons than within them, with dinoflagellates, chlorophytes, and diatoms dominating both periods. The phytoplankton community structure showed higher richness, diversity, and stability during autumn than in summer. Furthermore, redundancy analysis identified DIN/DIP, temperature, salinity, orthophosphate (PO₄³⁻), ammonia nitrogen (NH₄⁺), and depth as primary drivers, with DIN/DIP being the core factor structuring the phytoplankton assemblage. These results suggest that phosphorus limitation may drive the shift in phytoplankton community structure from diatom to dinoflagellate dominance, due to varying phosphorus utilization strategies among different phytoplankton. These findings provide novel insights into the impacts of anthropogenic activities on estuarine ecosystems and offer science-based guidance for managing nitrogen and phosphorus inputs to support global sustainable development goals. Full article

Urban green space (UGS) constitutes critical ecological infrastructure for climate adaptation and sustainable urban transitions. This review synthesizes the conceptual evolution of UGS, elucidating the coupled dynamics driven by anthropogenic interventions and climatic forces. We highlight that UGS has evolved from spontaneous vegetation to systematically planned infrastructure, serving dual cultural and ecological functions. While human drivers—spanning policy frameworks, species selection, and maintenance regimes—dictate the spatial morphology of UGS, climatic conditions and extreme weather events modulate vegetation resilience and performance, creating distinct bioclimatic patterns, particularly within Chinese cities. Collectively, these forces govern the structural integrity and ecosystem performance of UGS. Methodologically, this study combines a bibliometric analysis of Web of Science publications from 2000 to 2025 with a PRISMA-based systematic literature review and a semi-quantitative synthesis of recent empirical studies. The bibliometric analysis provides a global overview of research hotspots and thematic evolution in UGS research, while the in-depth synthesis and factor prioritization primarily focus on China-based studies published between 2021 and 2025. By integrating evidence on both human activities and climatic factors, this review clarifies the dominant driving mechanisms shaping UGS under rapid urbanization and climate change, while situating China-specific findings within the broader international literature. Although UGS delivers well-documented benefits for microclimate regulation and social well-being, accelerating urbanization and increasing climate complexity pressures indicate that existing management approaches could be further enhanced to meet emerging demands. Consequently, future UGS development should shift from quantitative expansion to qualitative optimization and spatial equity. We propose a research agenda prioritizing cross-climate comparative frameworks, smart maintenance technologies, and inclusive governance to bolster UGS resilience, thereby advancing long-term sustainable development goals. Full article

Exposure to fluoride is strongly associated with impaired intestinal function. Probiotics are widely regarded as an effective strategy to maintain microbial homeostasis and to mitigate the progression of fluoride-induced intestinal injury. This study aimed to evaluate the measurable protective effects of the probiotic strain Bifidobacterium animalis subsp. animalis (B. animalis subsp. animalis) GY007 in reversing high fluoride-induced ileal injury. The results showed that GY007 (1 × 10⁹ CFU/mL, once/daily) attenuated intestinal barrier disruption and alleviated ileal mucosal abnormalities in mice receiving fluoride (24 mg/kg) by gavage for eight consecutive weeks. GY007 attenuated elevated oxidative stress and modulated the inflammatory response associated with the TLR9/NF-κb/IRF7 signaling pathway. Microbiome and metabolomic analyses showed that GY007 reversed the dysregulation of the ileal microbial community structure and metabolite profiles. Spearman’s rank correlation analysis further supported a regulatory role for Bifidobacterium in this protective process and identified three key functional metabolites meriting further investigation: isocytosine (ISO), 7α,24S-dihydroxy-3-oxocholest-4-en-26-oic acid (OIC-7α), and sinapinic acid (SIA). Our findings demonstrate that GY007 protects against fluoride-induced ileal injury and elucidate the associated changes in the intestinal microbial community and metabolite profiles. This study provides new evidence clarifying the restorative effect of the probiotic GY007 on the ileum under environmental fluoride exposure, offering an integrative perspective on the interaction between microorganisms and their host. Full article

To address pipeline blockages and corrosion caused by moss, this study evaluates the effectiveness of two treatments, Isothiazolinone (IS) and layered double hydroxide–sodium pyrithione (LDH-SPT) modified hydrophobic resin membranes, in preventing moss growth. Furthermore, we closely examined how IS works at a molecular level to stop moss growth. The sequencing results revealed that the predominant algae identified in the pipeline moss community was a norank species of Trebouxiophyceae, accounting for 75.79%. Tests show that IS has strong moss inhibition. It works at low doses (0.2%) and becomes even more effective as the concentration increases. Furthermore, IS remains highly effective at inhibiting moss within a modified hydrophobic resin membrane, but its corrosion resistance is poor. The LDH-SPT@IS composite modified hydrophobic resin membrane addresses the corrosion problem of using IS alone and still works very well at inhibiting moss. Finally, the mechanism of IS’s inhibition of moss was elucidated based on experiments and existing literature. It functions by disrupting moss cellular DNA structure and interfering with the mitochondrial electron transport chain. This research provides the basis for developing efficient, durable, and eco-friendly solutions to prevent pipeline corrosion and moss growth, paving the way for new technologies and materials. Full article

Hyaluronic acid–dopamine (HA-Dopa) hydrogels have emerged as promising adhesive biomaterials for biomedical applications. However, the complex dependencies between formulation parameters and hydrogel performance pose challenges for rational material design. In this study, an interpretable machine learning framework was developed to investigate the structure–property relationships of HA-Dopa hydrogels. A dataset comprising 228 data points was collected from 37 peer-reviewed publications, representing heterogeneous experimental conditions across different research groups, and gradient boosting regression models were established to predict adhesion strength and elastic modulus, achieving test R² of 0.99 and 0.94, respectively, with stable performance across cross-validation splits. SHAP analysis revealed that HA molecular weight and dopamine substitution degree are the dominant factors governing adhesion, while mechanical properties exhibit more distributed dependence on multiple formulation parameters. The identified synergistic interactions between key features provide potential guidance for targeted formulation optimization. This work demonstrates the utility of interpretable machine learning in elucidating structure–property relationships and accelerating the development of functional hydrogels for biomedical applications. Full article

In nature, structures such as earwig wings and mimosa leaves exhibit remarkable folding and unfolding capabilities. Inspired by these biological mechanisms, this work investigates soft foldable and torsional actuators based on Kresling crease pattern, fabricated using soft TPE 85A material through 3D printing. These actuators enable both foldable grasping and torsional motions. An analytical geometric model is developed to characterize the relationship between structural parameters and the inscribed circle area of a single-layer soft actuator, thereby elucidating their influence on contraction magnitude and relative deflection angle. Treating the soft actuator as an equivalent spring system, a mechanical model relating vacuum pressure to contraction ratio is further established, revealing an approximately linear relationship. The actuators are subsequently integrated with suction cups to form two end-effectors, a foldable soft gripper and a torsional soft gripper, and mounted onto a UR5 robotic arm via a customized flange. Demonstration experiments show that the foldable gripper achieves gentle, adaptive grasping of diverse objects, while the torsional gripper replicates human-like twisting motion, such as opening a bottle cap. This study highlights the potential of Kresling-based soft grippers for practical deployment in automated production tasks, including precision assembly and fruit harvesting. Full article

Geopolymers, a class of alkali-activated aluminosilicate binders, have emerged as a sustainable alternative for expansive soil stabilization. In this study, the swelling behavior of geopolymer-treated bentonite was systematically investigated using a Taguchi orthogonal design, complemented by XRD, FTIR, and SEM analyses to elucidate the underlying mechanisms. Specimens were compacted to an initial void ratio of e = 1.1, sealed, and cured under controlled conditions (22 ± 2 °C and 70 ± 2% relative humidity) prior to testing. The free swell ratio (FSR) was determined using a standardized free swelling test in accordance with GB/T 50123-2019, which is technically consistent with ISO 17892-13, under zero vertical surcharge. Each orthogonal condition was tested using a single specimen, and the reported values represent individual measurements. The results show that NaOH concentration is the dominant factor controlling swelling response, with a quantified contribution of 55.04%. The swelling behavior exhibits a distinct two-stage trend, characterized by an initial enhancement at low alkali concentrations followed by a significant suppression beyond a critical threshold of approximately 3 mol/dm³. Microstructural analyses reveal that this transition is governed by a progressive interlayer cation exchange, the structural dissolution of clay minerals, and the formation of geopolymer gel, which densifies the soil matrix and restricts interlayer expansion. These findings provide quantitative and mechanistic insight into the role of alkali activation in expansive clay stabilization and establish a practical concentration threshold for optimizing swelling suppression. Full article

Fluoride-induced osteoarthritis (F-OA) is a debilitating manifestation of endemic fluorosis, with limited preventive or therapeutic strategies. Rosa roxburghii juice (RRJ), a traditional medicinal/edible product, has shown protective effects against skeletal fluorosis, yet its active constituents and molecular mechanisms are not fully understood. In this study, an integrated strategy combining bioinformatics analysis, network pharmacology, molecular docking and dynamics simulations, limited proteolysis–mass spectrometry (LiP–MS), and in vitro experiments was employed to systematically elucidate the protective mechanisms of RRJ against F-OA. Forty-four core F-OA-associated genes were identified, with TP53 and the p53 signaling pathway emerging as central regulatory hubs. Quercetin, Epicatechin, Emodin, and Ellagic acid were screened as key bioactive components of RRJ and demonstrated strong binding affinity toward core targets, including TP53. Cellular experiments showed that these compounds significantly attenuated sodium fluoride-induced cellular injury. LiP–MS analysis further revealed widespread protein conformational remodeling following treatment, with TP53 exhibiting pronounced structural sensitivity. Mechanistically, these active compounds mitigated fluoride-induced pathological changes by suppressing p53 mRNA expression and restoring proteasome-mediated p53 degradation. This study provides systematic pharmacological evidence supporting Rosa roxburghii fruit as a promising functional food for the prevention and management of skeletal fluorosis and F-OA. Full article

This study evaluated the effect of freezing and frozen storage at three temperatures (−20, −30, −40 °C) on hop (Humulus lupulus L.) secondary metabolites and antioxidant capacity. These temperatures were selected based on the glass transition temperature (T_g’) of the maximally freeze-concentrated matrix. Cones were analyzed after freezing (t₀) and up to 360 days (t₃₆₀) by high-performance liquid chromatography with ultraviolet diode-array detection (HPLC-UV/DAD) for bitter acids, prenylflavonoids and phenolic acids, and by the Folin–Ciocalteu, ABTS the radical cation scavenging assay (ABTS) and the ferric-reducing antioxidant power assay (FRAP) assays for total phenolic content and antioxidant activity. Confocal laser scanning microscopy (CLSM) at t₃₆₀ was used to relate microstructural damage to metabolite retention. Freezing at −40 °C ensured the highest retention of bitter acids, phenolic acids (gallic, syringic, vanillic, caffeic, chlorogenic), and antioxidant capacity, whereas xanthohumol and 8-prenylnaringenin reached their maximum levels at −30 and −20 °C, respectively. During frozen storage, changes in metabolite profiles were mainly driven by storage time rather than temperature; over 360 days, α-acids, colupulone, xanthohumol and selected phenolic acids increased, while most other compounds declined. Multivariate analysis and CLSM elucidated the relationships between process conditions, tissue structure and metabolite profiles, enabling the selection of freezing and storage temperatures to optimally preserve different targets of hop bioactives and overall indicating −40 °C as the most effective. Full article

The Maoniuping deposit, recognized as the world’s third-largest light rare earth (LREE) deposit, is characterized by exceptional ore-forming conditions and considerable exploration potential. Based on systematic mineralogical investigations of chevkinite, allanite, and bastnäsite, this paper synthesizes the trace elements and rare-earth element (REE) geochemical characteristics of these minerals to elucidate their enrichment mechanisms and metallogenic processes. The results reveal a crystallization sequence of chevkinite → allanite → bastnäsite, accompanied by a progressive decrease in the content of Nb, Ta, Zr, Hf, Sr, and Ba. This trend indicates continuous magmatic–hydrothermal evolution of the ore-forming fluids. REE enrichment exhibits distinct stages: early-stage enrichment of HREE, mid-stage enrichment of Ce, Pr, and Nd, and late-stage dominance of La. For chevkinite (δCe = 0.98–1.11, avg. 1.05; δEu = 0.75–0.87, avg. 0.82) and bastnäsite (δCe = 0.81–1.15, avg. 0.88; δEu = 0.58–0.79, avg. 0.66), the evolution process of the continuous increase in oxygen fugacity within the metallogenic system is recorded. The low-temperature, high-oxygen fugacity environment facilitates the incorporation of LREEs into bastnäsite lattices, enabling the formation of large-scale REE ore bodies at structurally favorable positions. These findings provide direct mineralogical evidence for understanding REE enrichment mechanisms in alkaline magmatic–hydrothermal systems and offer crucial insights for metallogenic process inversion and exploration assessment of analogous REE deposits. Full article

Background: Medicinal plants function as complex holobionts, with their therapeutic potential significantly shaped by the associated microbiome, particularly endophytic fungi. These symbionts engage in a sophisticated “chemical signaling” with their hosts, acting as biotic elicitors that modulate plant secondary metabolism while simultaneously responding to host cues to activate their own cryptic biosynthetic gene clusters (BGCs). This review aims to critically summarize the multi-layered mechanisms driving this metabolic crosstalk and evaluate strategies to harness this symbiotic intelligence for natural product discovery. Methods: A systematic literature survey spanning the last decade was conducted across major databases. The search specifically targeted studies investigating endophytic fungi in medicinal plants, focusing on experimental designs for BGC activation, applications of spatial metabolomics (matrix-assisted laser desorption/ionization mass spectrometry imaging, MALDI-MSI), and the structural elucidation of novel bioactive natural products through co-culture or in planta models. Results: Our analysis reveals that host-derived chemical cues, such as specific root exudates and oxylipins, act as primary triggers to awaken silent fungal BGCs. We collated numerous recently discovered bioactive metabolites—including novel polyketides, highly rearranged terpenoids, and unique alkaloids—demonstrating their potent antimicrobial and cytotoxic properties. Furthermore, a critical evaluation of spatial metabolomics studies demonstrates that metabolic exchange is highly localized at the plant–fungus interface, providing contextual insights that traditional bulk tissue extraction fails to capture. Conclusions: This review bridges the gap between ecological understanding and synthetic biology applications. We conclude that translating the mechanisms of this “chemical signaling” into biotechnological strategies offers a sustainable pathway for the bioproduction of high-value pharmaceuticals, thereby reducing reliance on the wild harvesting of medicinal plants. Full article

To elucidate the stability mechanisms of grid-forming (GFM) inverters governed by dispatchable virtual oscillator control (dVOC), this paper develops a comprehensive sequence-impedance modeling and stability analysis framework for dVOC-based GFM inverters with different inner-loop control structures. Three representative configurations are investigated: open-loop dVOC control, dVOC with dual-loop voltage–current control (DLC), and dVOC with virtual admittance control (VAC). For each configuration, unified positive-sequence impedance models are derived and analytically validated. Based on these models, the stability characteristics are first analyzed in a single-inverter grid-connected system under different grid strengths. The analysis is then extended to a mixed inverter system consisting of grid-forming and grid-following (GFL) inverters. Particular attention is paid to the impedance interaction between GFM impedance shaping and the capacitive negative damping introduced by GFL inverters under weak-grid conditions. Quantitative analyses reveal that the dVOC–DLC configuration significantly enhances oscillation damping in mixed systems. Under benchmark scenarios, stable operation can be ensured with approximately a 25% GFM capacity penetration. In contrast, the open-loop and VAC configurations require around 50% and 75% capacities, respectively, to maintain stability. These findings indicate that the DLC-based inner-loop design offers superior stability margins while substantially reducing the required GFM capacity, thereby improving economic efficiency. This study establishes a quantitative impedance-based criterion for inner-loop control selection and provides practical design guidelines for deploying dVOC-based GFM inverters in future converter-dominated power systems. Full article

Edible mushrooms have long been valued as functional foods and traditional remedies, yet a significant developmental gap hinders their transition from nutraceuticals to standardized pharmaceutical ingredients. This narrative review provides a comprehensive and integrative analysis of edible mushroom-derived bioactive compounds as emerging candidates for pharmaceutical development. It examines major chemical classes, including polysaccharides (e.g., β-glucans), proteins (e.g., lectins, FIPs), triterpenoids (e.g., ganoderic acids), nucleosides (e.g., adenosine and cordycepin), and phenolic compounds, which underpin immunomodulatory, anticancer, antioxidant, anti-inflammatory, and metabolic activities. Beyond bioactivity, the review critically examines the downstream processing pipeline required for translation into pharmaceutical ingredients, encompassing controlled biomass production, pre-extraction processing, extraction technologies, isolation and purification strategies, and structural elucidation techniques. Key bottlenecks are identified, including bioavailability limitations of β-glucans (2–5%), lack of standardization, limited human clinical evidence, and regulatory constraints, explaining why robust preclinical evidence has not consistently translated into clinical success. Emerging solutions are also highlighted, including application of multi-omics tools, nano-encapsulation strategies, and synthetic biology approaches to improve scalability and reproducibility. By synthesizing research on natural product chemistry, biotechnology, and pharmacology, this study maps the journey of edible mushrooms from traditional dietary components to pharmaceutical-grade ingredients, providing a focused resource for researchers and industry stakeholders aiming to navigate mushroom-based drug development. Full article