Search Results (217)

Ultra-deep lattice-like fractured carbonate reservoirs, formed by multi-period tectonic movements, feature strong heterogeneity, multi-scale fracture nesting, and anisotropic in situ stress. However, hydraulic fracture (HF) propagation behaviors within these complex formations remain poorly understood. In this study, using an unstructured fracture network approach, we simulated HF propagation in two typical fault-controlled lattice-like structures: compressive-torsion and pull-apart overlap zones. The performance of commingled, staged, and temporary plugging fracturing was evaluated, alongside sensitivity analyses of wellbore orientation, plugging timing, pump rate, and fluid viscosity. Results indicate that HFs in compressive-torsion zones exhibit long, straight geometries with local tensile activation points. Conversely, pull-apart overlap zones promote step-shaped, multi-branched fractures with superior lateral connectivity. The optimal timing for temporary plugging exhibits a delayed trend with increasing natural fracture density, ranging from 50% to 70% of the fracturing process in compressive-torsion zones, whereas an earlier implementation is preferred in pull-apart overlap zones, occurring at 33–65% of the fracturing process. Furthermore, HFs in compressive-torsion zones are less sensitive to viscosity and pump rate. To optimize stimulated volume, a moderate viscosity of 50–60 mPa·s is universally recommended. Regarding pump rates, 8–10 m³/min is ideal for balanced connectivity in pull-apart overlap zones, whereas >12 m³/min is required for compressive-torsion zones. These findings provide critical theoretical and engineering guidelines for differentiated fracturing strategies in ultra-deep reservoirs. Full article

Benefiting from outstanding thermal durability at elevated temperatures and eco-friendly characteristics, oxide-based thermoelectric substances exhibit great application potential in residual heat recycling and intelligent textile defect inspection. Zinc oxide (ZnO) exhibits excellent thermal stability but suffers from high lattice thermal conductivity and low carrier concentration. Herein, we systematically investigate Ni-doped ZnO ceramics. XRD(X-ray diffraction) confirms homogeneous wurtzite solid solutions with lattice contraction following Vegard’s law. Ni doping enhances electrical conductivity from 45.45 to 145.80 S·cm⁻¹ by promoting oxygen vacancy formation, while first-principles calculations reveal a narrowed bandgap. For specimens with x ranging from 0.0040 to 0.0044, the power factor attains approximately 8.0 μW·cm⁻¹·K⁻² at 873 K, representing a 41% enhancement. Meanwhile, intensified phonon scattering leads to an evident suppression of lattice thermal conductivity, which lowers the overall thermal conductivity down to 2.38 W·m⁻¹·K⁻¹ under 873 K. Benefiting from the above optimizations, the sample delivers a peak thermoelectric figure of merit (ZT) value of 0.27 at this temperature, which is 170% greater than that of undoped ZnO. In addition, the Vickers hardness rises from 242.70 HV to 281.45 HV. Such observations verify that nickel doping can successfully decouple charge and heat transport behaviors. This approach provides a feasible route toward developing oxide thermoelectric systems with upgraded thermoelectric performance. Full article

Conventional polydimethylsiloxane (PDMS)-based antifouling coatings, despite their inherent fouling-release capability, exhibit critically insufficient antifouling performance under static seawater conditions. Inspired by the synergistic physical–chemical defense strategy of sessile marine organisms, specifically sea anemones, which combine a physical mucus barrier with antimicrobial peptide secretion, the present work develops a multi-mechanism hybrid coating—designated as sea anemone-inspired fluorosilicone polyurethane—that integrates low-surface-energy physical antifouling and cationic antibacterial chemical antifouling. This coating system is constructed from silicone polyurethane (PDMS-PU), a cationic antibacterial moiety (PDMS-N⁺), and fluorinated functional monomers. Through systematic compositional optimization, an optimal formulation (P-4) is identified, which achieves a fracture elongation of 78.19%, a normal adhesion strength of approximately 2.5 MPa, a water contact angle of 120°, and a surface energy of 12.86 mN/m. Notably, its antibacterial rates against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) exceed 95%. The resultant coating uniquely synergizes low surface energy, potent antibacterial activity, excellent mechanical properties, and thermal stability, thereby enabling long-term and stable antifouling performance in static seawater environments. This work provides a crucial technological foundation for the engineering application and industrialization of green, durable marine antifouling coatings. Full article

Clostridium perfringens type A causes neonatal clostridial enteritis, hemorrhagic enteritis, and sudden death syndrome in cattle. This study examined a fatal outbreak at a fattening farm housing 58 adult yaks in Southwest China, with an incidence of 22.41% (13/58) and a 100% case fatality rate. Histopathology of deceased yaks showed widespread multi-organ hemorrhage and severe hemorrhagic enteritis. A specific PCR assay amplified the alpha-toxin gene of Clostridium perfringens, while no other pathogens were detected. Clostridium perfringens was isolated from small intestinal contents using TSC agar, designated strain CQ1, and identified as type A through toxinotyping. Whole-genome sequencing revealed that strain CQ1 carries the core alpha-toxin gene along with key accessory virulence determinants (pfoA, colA, and cloSI). Phylogenomic analysis based on core single-nucleotide polymorphisms revealed that strain CQ1 is clustered into a distinct, independent evolutionary lineage with an existing historical yak isolate and a canine-origin isolate. Intraperitoneal challenge in mice confirmed its extreme lethality, causing 100% mortality within 36 h with severe intestinal necrosis. These findings provide fundamental genetic resources for understanding the virulence mechanisms and genetic background of this pathogen and offer critical insights for preventing and controlling clostridial diseases in high-altitude yak farming. Full article

Aim: To establish and validate a quantitative transporter-mediated imaging framework based on gadoxetic acid-enhanced T1 mapping for assessing liver functional reserve (LFR) and to investigate the physiological significance of the relative change in longitudinal relaxation rate (ΔR1%) as a quantitative imaging biomarker. Methods: Female C57BL/6J mice (6–8 weeks old) representing five experimental liver conditions (control, transporter-deficient Slco1b2/Slco1a5 double-knockout, carbon tetrachloride-induced fibrosis, methionine–choline-deficient diet-induced steatohepatitis, and alcohol-associated fatty liver disease; n = 6 per group) underwent serial Gd-EOB-DTPA-enhanced T1 mapping. Quantitative ΔR1% was calculated to characterize hepatobiliary enhancement kinetics. Liver functional reserve was independently evaluated using multispectral optoacoustic tomography of indocyanine green (ICG) pharmacokinetics and serum ICG retention assays, with histopathological and hepatocellular transporter analyses performed for mechanistic validation. Longitudinal data were analyzed using restricted maximum likelihood (REML)-based mixed-effects models. Intergroup comparisons were performed using one-way ANOVA or Kruskal–Wallis tests with appropriate post hoc analyses, and associations between imaging and functional parameters were evaluated using Spearman rank correlation analysis. A two-sided p < 0.05 was considered statistically significant. Results: Five experimental liver models exhibited distinct transporter-dependent hepatobiliary enhancement patterns. The transporter-deficient knockout mice showed minimal enhancement, whereas fibrosis and steatotic liver injury models demonstrated intermediate but clearly distinguishable functional profiles. Longitudinal mixed-effects analysis identified significant effects of time, experimental group, and time-by-group interaction on ΔR1% dynamics (all p < 0.0001). Although MRI-derived ΔR1% parameters were not significantly correlated with regional optoacoustic ICG kinetics, ΔR1% area under the curve showed a strong inverse correlation with serum ICG retention at 600 s (r = −0.729, p < 0.0001), indicating that MRI-derived ΔR1% and ICG-based measurements provide complementary rather than interchangeable assessments of liver function. Histological and molecular analyses further demonstrated marked heterogeneity in fibrosis, steatosis, and hepatobiliary transporter expression across models, whereas transporter abundance alone did not consistently predict imaging-derived functional performance. Conclusions: Quantitative Gd-EOB-DTPA-enhanced T1 mapping provides a transporter-mediated imaging framework for evaluating hepatic functional reserve across mechanistically distinct liver injury models. As a normalized quantitative imaging biomarker, ΔR1% captures the integrated functional consequences of hepatobiliary transport dysfunction and complements established liver function tests. These findings support the translational potential of quantitative T1 mapping as a standardized, noninvasive approach for assessing liver functional reserve. Full article

Phosphorus (Pi) deficiency limits plant productivity. Light quality modulates growth and stress responses, but its interaction with Pi starvation in banana is unclear. We investigated physiological, transcriptomic, and metabolomic responses of banana seedlings to low Pi under white (WL), red (R), far-red (FR), blue (B), and ultraviolet (UV-A) light. FR light promoted shoot elongation and increased phosphorus, iron, and calcium accumulation, whereas B and UV-A exacerbated growth inhibition and oxidative stress (higher H₂O₂, MDA, and proline). Transcriptomics revealed that B and UV-A enriched cell cycle and stress pathways, while FR enriched photosynthesis and cell wall biogenesis. Expression of phosphate transporters and starvation-responsive genes was spectrum-specific. Metabolomics showed B and UV-A triggered massive accumulation of ABA, flavonoids, and secondary metabolites, indicating strong stress defense. Antioxidant enzyme activities were differentially activated: B upregulated SOD, CAT, and POD; UV specifically enhanced GSH-Px. Integrated correlation networks revealed distinct regulatory hubs: blue light centered on ROS scavenging, red light on phosphate transport. Our findings demonstrate that FR light acts as a positive regulator, while B and UV-A act as additional stressors under Pi deficiency, providing a mechanistic framework for using light spectra to improve crop resilience in Pi-limited conditions. Full article

Tea breeding increasingly requires a continuous evidence chain from germplasm identity to molecular variation and progeny performance, but cultivar passports, genome resources, transcriptome profiles, metabolite data and breeding records are often managed separately. Here, we present Ningbo TeaBase (NB-TeaBase), an open, cultivar-centered database for robust-bud tea (Camellia sinensis) breeding. The platform uses named cultivars as the organizing unit and integrates germplasm passport information for eight elite cultivars with 23 chromosome-level genomes, whole-genome resequencing variants, RNA-seq expression profiles, untargeted LC-MS/MS metabolite features, annotations and downloadable records. Shared cultivar, gene, variant, pathway and metabolite identifiers allow users to characterize a cultivar across genomic, transcriptomic and metabolic layers and to connect these profiles with breeding records. A parental-prediction module incorporates genome-wide markers and phenotypes from 122 progeny assigned to seven observed parental combinations; it reports genomic estimated breeding values (GEBVs) for candidate crosses and observed-family general and specific combining-ability summaries for seven traits. By combining germplasm documentation, multi-omics evidence and progeny-informed cross ranking, NB-TeaBase supports cultivar evaluation, parent selection, cross prioritization and breeding strategy formulation. Current prediction outputs remain exploratory because the phenotypic training data cover only seven parental combinations and require broader validation. Full article

This paper presents a comprehensive numerical investigation into the transient thermo-structural response of axial bellows during start-up and shutdown cycles in long-distance heating pipelines. Using ANSYS-based transient thermal–structural coupling finite element analysis under the pure linear elasticity and constant internal pressure, the spatio-temporal evolution mechanisms of temperature fields, axial deformation, and equivalent stress are systematically analyzed. The results demonstrate the highly synchronized evolution between temperature and deformation fields, with maximum axial deformation and equivalent stress consistently concentrated at the convolution root and transition arcs. Under steady-state high-temperature conditions (130 °C), the maximum equivalent stress reaches 332.78 MPa. However, after complete cooling and unloading, minimal residual deformation (≤0.001 mm) and residual stress (8.86 MPa) are observed, satisfying the pressure vessel shakedown criteria and confirming the inherent self-limiting nature of thermal secondary stresses. A specific decoupling phenomenon is revealed during the high-temperature steady-state holding period, where the deformation stabilizes while the stress undergoes secondary redistribution. The comparative analysis of different temperature change rates indicates that the fast start-up/shutdown (0.55 °C/s) induces severe transient temperature gradients, causing a nearly 50% increase in the maximum equivalent stress compared to the slow start-up/shutdown (0.275 °C/s). This study provides theoretical foundations for the service safety assessment of axial bellows and recommends gradual heating/cooling operation strategies (≤0.3 °C/s) to mitigate structural thermal shock risks. Full article

The goaf backfilling with the coal gangue is an effective strategy for mitigating the mining-induced surface subsidence and reducing the solid waste accumulation. However, the conventional backfilling methods often suffer from limited transport efficiency, poor material distribution, and high operational cost. The present paper proposes a novel technique using an inclined spiral propeller to propel the gangue particles into the goaf, aiming to improve both the backfill rate and spatial uniformity. A three-dimensional parametric model of the inclined screw conveyor is developed, and the discrete element method (DEM) is employed to simulate the dynamic transport and placement of the gangue particles. An L9 ($3^3$) orthogonal experimental design is implemented to systematically evaluate the effects of the rotational speed (240, 300, 360 r/min), inclination angle ($30°$, $45°$, $60°$), and screw pitch (180, 240, 300 mm) on the two critical performance indicators, namely, filling mass and spreading coverage area. The range analysis and matrix analysis are performed to determine the primary influencing factors and to identify the optimal parameter combination for the multi-objective performance. The results show that the inclination angle is the dominant factor for the filling mass, with a $60°$ angle yielding the highest throughput (38.60 kg). In contrast, the rotational speed is the dominant factor for the spreading coverage area, where an increase from 240 to 360 r/min nearly triples the covered area. The optimal compromise for the comprehensive backfilling performance is the rotational speed 360 r/min, inclination angle $60°$, and screw pitch 300 mm, which simultaneously achieves the high transport capacity (36.65 kg) and the largest spreading area (2.87 ${\mathrm{m}}^2$). The present study provides a theoretical and methodological foundation for the engineering design of efficient, low-cost goaf backfilling systems. Full article

This meta-analysis combined the results of 61 independent studies published in 2005–2025 to examine polyamine-mediated responses to aluminum, cadmium, lead, chromium, copper, manganese, and selenium stress in plants. The logarithm ratio of responses (lnRR) under the random-effects model was used to calculate the effect sizes. Polyamine application significantly (p < 0.001) enhanced plant growth, with strong increases in root elongation (lnRR = 0.490, 95% CI: 0.362–0.618), fresh weight (lnRR = 0.413, 95% CI: 0.347–0.480), and dry weight (lnRR = 0.475, 95% CI: 0.409–0.541). Oxidative stress was markedly reduced, as reflected by decreases in reactive oxygen species accumulation (lnRR = −0.585, 95% CI −0.682 to −0.487, p < 0.001), hydrogen peroxide content (lnRR = 0.005, 95% CI −0.244 to 0.254, p = 0.968), and lipid peroxidation (lnRR = −0.487, 95% CI −0.578 to −0.397, p < 0.001). The antioxidant defenses were strengthened, and the levels of superoxide dismutase (lnRR = 0.468, p < 0.001) and catalase activity (lnRR = 0.373, p < 0.001) increased significantly. Metal accumulation was consistently reduced in polyamine-treated plants (lnRR = −0.392, 95% CI −0.460 to −0.324, p < 0.001). Supplementary genetic-level data indicated that metal stress triggers polyamines to regulate metal transporters, polyamine biosynthesis genes, antioxidant-related genes, and hormone-signaling pathways. Collectively, these data points make polyamines a key controller of plant metal stress tolerance and offer a quantitative and mechanistic system to apply them to metal-impacted agroecosystems. Full article

This paper introduces a weak-magnetic-field measurement system characterized by a large-scale uniform magnetic field and a low magnetic limit of detection (LOD). The system employs a four-ring coil assembly housed within a multi-layer magnetic shielding cavity, generating a uniform magnetic field region of 120 mm while achieving a minimum LOD of less than 10 pT. The performance of the weak-magnetic-field measurement system is appropriately validated using a bulk magnetic–electric (ME) sensor. The experimental results confirm the system’s dual functionalities in both magnetic sensor calibration and the measurement of weak magnetic parameters. Notably, this methodology is readily applicable to various forms of weak-magnetic-field measurement. Full article

Mountainous cultural landscapes, characterized by fragmented heritage sites, present significant challenges for integrated conservation and regional planning. Taking the Mount Song Culture Circle in Dengfeng City, China—a World Heritage site embodying the core of Chinese ritual civilization—as a case study, this study proposes an adaptive minimum cumulative resistance (MCR) gravity model to optimize heritage corridor resilience against spatial fragmentation and development imbalances. Based on a spatial database of 294 cultural relic units, the adaptive model introduces a dynamic cultural value weight (CVIndex = 0.82) and a time decay function (λ = 0.05) to capture the interplay between cultural significance and ecological constraints—features absent in traditional static approaches. The model identifies three optimized heritage corridor networks—”Seeking Wisdom in the Mountains”, “Searching for Culture in the Landscape”, and “Exploring the City Along the River.” Compared with a traditional static MCR model (αindex = 0.42; core area node density = 0.74 nodes/km²), the adaptive approach improves network connectivity by 37% (α-index = 0.58, p < 0.01) and increases core area heritage node density to 1.12/km². Space syntax analysis further confirms that optimized network integration values strongly correlate with cultural dissemination efficiency (R² = 0.78, p < 0.01, n = 48). This research offers a methodological innovation for resilient conservation of complex cultural landscapes in World Heritage contexts. Full article

Accurate bearing fault diagnosis in electric drive systems is crucial for ensuring the safety and reliability of new energy vehicles. Aiming at the problem of inaccurate bearing fault diagnosis caused by the failure to fully utilize the time-frequency feature information of bearing faults and the lack of an adaptive selection mechanism for features, an intelligent bearing fault diagnosis method based on wavelet packet decomposition (WPD) time-frequency feature enhancement is proposed in this paper. First, the collected vibration signals are enhanced using WPD to obtain the full-frequency-band time-frequency information, which provides input for the bearing fault diagnosis model. Second, a hybrid neural network CNN-BiLSTM-AM for bearing fault diagnosis is constructed. On the basis of using the convolutional neural network (CNN) improved with cross-convolutional layers to extract multiscale spatial features of the input data and the bidirectional long short-term memory network (BiLSTM) to capture the bidirectional temporal dependence between features, the attention mechanism (AM) is introduced to adaptively weight and enhance key global features. Finally, a fully connected layer is employed to achieve intelligent classification of bearing fault states. Validation on a laboratory test dataset shows that the proposed method achieves an average diagnostic accuracy of 98.67%, outperforming existing benchmark models and exhibiting strong generalization ability. This study provides an effective and practical intelligent fault diagnosis scheme for bearings in electric drive systems. Full article

The present study aimed to compare the composition structure, interfacial, and antioxidant activities of flaxseed protein isolates (FPIs) in different flaxseed varieties. The results showed that apparently intact protein bodies (PBs) were manifested as densely staining cytoplasmic inclusions with distinct boundaries and varying diameter ranges among different flaxseed varieties. Through alkali extraction with isoelectric precipitation, FPIs exhibited a relatively small and irregular lamellar strip structure with varying sizes and shapes packed with spherical particles in studied flaxseed varieties. The different composition structures of FPIs among studied flaxseed varieties were also obtained, involving the protein subunits’ intrinsic fluorescence properties, secondary structures, and amino acid profiles. These structural differences also led to differential purities, aqueous solubility, dispersion properties, and surface charges. Moreover, the varying emulsifying and foaming properties of FPIs from different flaxseed varieties were also observed due to the formation of coarse lipid droplets (5~40 μm) and foams (20~100 μm) with the specific structure of the oil/gas–water interface and bulk aqueous phase. The retention of phenolic compounds into FPIs still displayed evident variety specificity from 323 to 478 mg/100 g and 210 to 347 mg/100 g, which definitely led to escalated antioxidant activities. Thus, FPIs from Longya 13# and Neiya 9# flaxseed varieties were screened for favorable emulsifying and foaming properties due to the balanced molecular rigidity/unfolding and interfacial adsorption/stabilization behavior. Full article

Background: Pyrroloquinoline quinone (PQQ), a naturally occurring redox cofactor with potent antioxidant and anti-inflammatory properties, has been shown to protect against cardiac injury. However, its therapeutic potential in diabetic cardiomyopathy (DCM) induced by Type 2 diabetes mellitus (T2DM) and the underlying mechanisms remain poorly understood. Methods: A T2DM mouse model was established via a high-fat diet and low-dose STZ. We investigated the cardioprotective effects of 12-week oral PQQ administration, assessing fasting blood glucose, oral glucose tolerance, cardiac function, myocardial histopathology, blood biochemistry, mitophagy, and NLRP3 inflammasome activation. In vitro experiments using AC16 cardiomyocytes exposed to palmitic acid and high glucose were also conducted. Results: Results showed PQQ significantly improved cardiac function, attenuated remodeling, and reduced proinflammatory cytokines in mice with T2DM, regulated key mitophagy-related proteins (Parkin, Beclin-1, LC3B-II, p62), and downregulated NLRP3 inflammasome pathway components (Caspase-1, NLRP3, IL-1β, IL-18). In vitro experiments demonstrated that PQQ reduced reactive oxygen species (ROS) production, improved mitochondrial membrane potential, promoted mitophagy, and inhibited NLRP3 inflammasome-mediated pyroptosis. Conclusions: PQQ alleviates DCM in mice with T2DM by improving mitochondrial quality control, promoting mitophagy, and subsequently inhibiting NLRP3 inflammasome-mediated pyroptosis, highlighting its potential as a promising therapeutic agent for T2DM-associated cardiomyopathy. Full article