Search Results (16,123)

Liquid- and solid-state fermentation are both used to produce Eurotium cristatum-fermented Fu tea, but their final soluble products have rarely been compared directly. We compared a liquid-state fermented tea infusion (LFt-D7) with an aqueous extract of solid-state fermented Fu tea (SFt-D7), using an unfermented sterilized tea extract (SHt-D0) as the reference group. LFt-D7 developed a darker reddish-brown appearance and had higher theaflavin and theabrownin contents, lower thearubigin content, and larger Commission Internationale de l’Éclairage L*a*b* (CIELAB) color differences than SHt-D0 and SFt-D7. Liquid chromatography–tandem mass spectrometry (LC–MS/MS) profiling separated the three endpoint groups; 221, 180, and 203 Level 2 annotations met the variable importance in projection (VIP > 1) and nominal p < 0.05 screening criteria in LFt-D7 versus SHt-D0, SFt-D7 versus SHt-D0, and LFt-D7 versus SFt-D7, respectively. Targeted analyses showed substantially lower free amino acid levels in SFt-D7. LFt-D7 retained a larger soluble free-amino-acid pool, had the highest total quantified flavonoid content with a stronger flavanol contribution, and showed higher relative peak-intensity signals for selected alkaloid- and phenolic acid-related metabolites. Mantel analysis showed covariation between metabolite modules and pigment indices, CIELAB parameters, total free amino acid (FAA) content, and total quantified flavonoid content. Together, these results show that the two complete preparation routes produce different soluble chemical profiles. Full article

Polysaccharides are major bioactive constituents and quality-related components of Anoectochilus roxburghii. However, how polysaccharide accumulation varies among cultivars and tissues remains poorly understood. Here, crude polysaccharide content was quantified in leaves and stems of three cultivars, Yuanye (YY), Hongxia (HX), and Jianye (JY), and the underlying molecular basis was investigated using transcriptomics, targeted sugar metabolomics, and integrated transcriptome–metabolome analysis. Stems accumulated significantly higher levels of crude polysaccharides than leaves, whereas cultivar-dependent differences were most pronounced in stems. JY stems showed the highest crude polysaccharide content, reaching 357.81 mg g⁻¹ dry weight. Transcriptomic and metabolomic profiles clearly differentiated the cultivars and tissues. Metabolic differences were concentrated at a limited number of sugar-metabolic nodes, whereas the transcriptome showed extensive transcriptional reprogramming. Integrative analyses consistently implicated starch and sucrose metabolism, precursor-sugar interconversion, nucleotide-sugar biosynthesis, and sugar transport, partitioning, and intracellular allocation in differential polysaccharide accumulation. Glucose and D-fructose emerged as key hub metabolites linking transcriptional variation to sugar-metabolic remodeling. These results suggest that tissue- and cultivar-dependent polysaccharide accumulation is associated with coordinated changes in sucrose turnover, precursor sugar supply, nucleotide-sugar formation, and sugar partitioning, particularly in stems. This study provides molecular evidence for the selection of high-polysaccharide germplasm and quality evaluation of A. roxburghii. Full article

Silage maize is an important forage crop in China and globally. Applied nitrogen (N) is crucial for increasing the harvest yield (aboveground dry matter) of silage maize. However, there is a lack of information on how nitrogen rate affects the harvest yield of silage maize in different planting regions and under different climatic and soil conditions in China. A meta-analysis was conducted to quantify and evaluate the effects of N rate on the harvest yield and N fertilizer contribution rate of silage maize in China and different planting regions in the country based on research published from 2000 to 2025. The effects of mean annual temperature, annual precipitation, soil properties, planting density, and cultivar used on the maize yield response were also investigated via subgroup analysis. The means of the N rate, harvest yield, and N contribution rate for silage maize in China were 211 kg ha⁻¹, 20,117 kg ha⁻¹, and 27%, respectively. In the southwest hilly and mountainous region, silage maize exhibited the highest harvest yield-change rate (55.41%) under a N rate of >0–100 kg ha⁻¹. In Northern China, the Huang-Huai Plain region, and the southern hilly region, the maximum harvest-yield-change rates for silage maize (31.42%, 54.11%, and 42.66%) were observed at a N rate of >200–300 kg ha⁻¹. In northwest inland China, the maximum harvest-yield-change rate (50.76%) of silage maize occurred at a N rate of >300 kg ha⁻¹. Furthermore, the aggregated boosted tree algorithm was adopted to quantify the relative contribution of N rate, annual mean temperature, annual precipitation, soil pH, soil organic matter, soil type and texture, cultivar selected, and planting density to the harvest yield and N contribution rate of silage maize. Soil type made the greatest contribution to the yield of silage maize in China, accounting for 41.36%, followed by cultivar (40.28%) and planting density (5.97%), and the total contribution of the three factors reached 87.61%. Soil type exhibited the highest contribution (26.35%) to the N contribution rate of silage maize in China, followed by cultivar (22.36%) and planting density (15.11%). The combined contribution of the three factors was 63.82%. Based on the dual criteria of maximizing harvest yield and the N contribution rate, the optimal N rates found for silage maize were 173–300, 110–200, 311–395, 168–270, and 92–270 kg ha⁻¹ for Northern China, the Huang-Huai Plain region, northwest inland China, the southern hilly region, and the southwest hilly and mountainous region, respectively. Meanwhile, in Northern China, the Huang-Huai Plain region, northwest inland China, the southern hilly region, and the southwest hilly and mountainous region, the increase in the yield of silage maize at harvest reached its maximum, and the corresponding silage maize cultivars were Yayu 8, Baimaya, Xinyu 9, Aoyu 5102, and Yuqingyu 3, respectively. This study provides reasonable guidance on suitable N rates for improving the yield and N contribution rate of silage maize in China and various other planting regions. Full article

NCED proteins play a critical role in drought, salt, and cold stress responses through ABA biosynthesis in plants. However, little information is currently available regarding the NCED gene family in Brassica species. Twenty-six putative BjNCED genes were identified in the genome of Brassica juncea, and found to be distributed on 15 chromosomes. Phylogenetic analysis suggested that these members could be classified into six subfamilies. The putative cis-elements were identified in the promoter regions of these BjNCED genes, and thought to be related to phytohormones, light, and abiotic stress responses. qRT-PCR analysis of five genes (BjNCED1, BjNCED4, BjNCED7, BjNCED16 and BjNCED18) revealed that, under salt stress, BjNCED16 and BjNCED18 showed transient induction, whereas exogenous ABA produced gene-specific and time-dependent expression patterns, including pronounced induction of BjNCED16 at 24 h. Low-temperature treatment strongly induced four of the five examined genes at 6 h. Analysis of the BjNCED genes in this study provides a valuable foundation for future investigations into the functional roles of the BjNCED family in response to growth, development and stress. Full article

Background: Dangguibuxue decoction (DD), containing Angelica sinensis (Oliv.) Diels (AS) and Astragalus membranaceus (Fisch.) Bge. (AM) (1:5), is a well-known traditional Chinese medicine (TCM) used for strengthening qi and nourishing the blood. DD has shown therapeutic effects in nephropathy patients. However, the underlying mechanisms based on the traditional efficacy are still not fully elucidated. Methods: The chemical constituents in DD were identified using UPLC-MS/MS. Network pharmacology analysis was applied to predict the potential target genes and associated signaling pathways. A renal fibrosis mouse model was induced by the intraperitoneal injection of aristolochic acid I (AA I) at 3.0 mg/kg. Mice were treated with AM, AS, and DD at two dosages by oral gavage for 30 days. Body weights, serum biochemistry, hematology, and histopathology observations were assessed. The key targets predicted were validated using qRT-PCR and Western blotting. The active constituents were screened by molecular docking, and their anti-fibrotic effects were evaluated through in vitro assays. Results: DD effectively improved renal functions and alleviated AA I-induced renal fibrosis. DD alleviated anemia and upregulated the expression of Erythropoietin (EPO). Network pharmacology analysis indicated the involvement of signaling pathways, including the PI3K/Akt, hypoxia-inducible factor-1α (HIF-1α) and transforming growth factor-β (TGF-β) signaling pathways. Experimental validation further demonstrated that DD reduced the protein expression of HIF-1α, collagen I, and TGF-β, and the ratios of phosphorylated Smad2/3 to total Smad2/3. Molecular docking and in vitro assays suggested that rutin may be a potential bioactive compound in DD. Conclusions: This research indicated that DD ameliorated AA I-induced renal fibrosis in mice, which may be associated with the modulation of HIF-1α and TGF-β/Smad signaling pathways. Rutin may be a potential bioactive compound in DD with anti-fibrotic activity, but further studies are still needed to clarify the content of rutin in DD, the amount of its exposure in the body, and its contribution to the effects of DD. Full article

Developing context-specific drought regionalization is crucial for targeted risk management, as drought evolves as a cascading hazard driven by complex land–atmosphere interactions rather than isolated climatic anomalies. However, conventional regionalization frameworks remain largely static and fail to capture the dynamic propagation from meteorological forcing to agricultural impacts. To address this limitation, we developed a framework that links continuous drought dynamics to discrete drought events, enabling identification of propagation patterns and their associated environmental mechanisms across the Loess Plateau, China. By integrating run theory, dimensionality reduction, clustering, and explainable machine learning, we identified three distinct drought propagation regimes: Propagation Blocked, Disaster Amplified, and Response Desensitized zones. At the regional scale, eco-hydrological factors, particularly vegetation productivity and soil moisture dynamics, showed the strongest attribution signals for differentiating drought propagation regimes. However, regime-specific environmental associations differed substantially: (i) propagation blockage was associated with terrain–vegetation interactions; (ii) disaster amplification was associated with low ecological productivity and declining soil moisture; and (iii) response desensitization was associated with intensive agricultural activities and relatively favorable soil moisture conditions, which may partly buffer vegetation responses to thermal and meteorological stress and create apparent resilience that may mask underlying hydrological vulnerability. SHAP analysis further indicated that topography and thermal conditions were strongly associated with broad-scale differentiation, while eco-hydrological conditions showed stronger associations with local regime-specific responses. Anthropogenic activities may also be associated with altered drought propagation pathways and potential risks of unsustainable water use. These findings highlight drought as a dynamic propagation process rather than a static hazard and provide a basis for targeted drought management strategies. Full article

Fragrant pear canker, caused by Cytospora pyri, is a major branch disease that reduces the productivity and longevity of Korla fragrant pear orchards in Xinjiang, China. During infection and lesion expansion in woody tissues, C. pyri must breach the host cell wall barrier, in which pectin degradation plays a central role by weakening intercellular adhesion and disrupting tissue integrity. Members of glycoside hydrolase family 28 (GH28), represented mainly by polygalacturonases and other pectin-degrading enzymes, are closely involved in fungal invasion and colonization. However, the composition and virulence-related functions of this gene family encoding for these enzymes in C. pyri remain unclear. In this study, GH28 genes were systematically identified and comparatively analyzed in C. pyri and closely related Cytospora species. Infection-stage expression profiling and functional validation were then performed to assess their roles in pathogenicity. A total of 73 GH28 genes were identified across five Cytospora species, including 15 in C. pyri. Most C. pyri GH28 proteins were predicted to be acidic, hydrophilic, extracellularly secreted proteins carrying conserved motifs. Phylogenetic analysis showed that C. pyri GH28 members were closely related to homologs from C. mali. Genomic distribution analysis revealed that these genes were dispersed across multiple scaffolds, with no obvious tandem duplication events. RT-qPCR analysis showed that all seven candidate GH28 genes were induced during infection of fragrant pear branches, with VP1G_08835 and VP1G_03209 exhibiting strong expression responses at 6 dpi. Functional validation further showed that deletion of VP1G_08835 impaired vegetative growth and reduced lesion length on detached pear branches by 26.62% compared with the wild type, whereas complementation restored these phenotypes. These findings demonstrate that GH28 genes participate in C. pyri infection and identify VP1G_08835 as an important GH28 member required for normal growth and contributing to virulence. Full article

In order to verify the reliability and engineering applicability of the AE-CMT welding technology for magnesium alloy joining, AE-CMT welding experiments were conducted at welding speeds ranging from 0.5 to 3.0 m/min on 1.5 mm-thick H24-temper AZ31B magnesium alloy sheets using imported 1.2 mm-diameter WE-33M welding wire. Within the welding speed range of 0.5–3.0 m/min, increasing the welding speed progressively reduces heat input, thereby refining grains and homogenizing the microstructure. The welding heat input of the AE-CMT process ranges from 0.47 KJ/mm to 1.07 KJ/mm, and the grain sizes of the weld zone and HAZ are 9.61–14.18 μm and 6.35–12.22 μm, respectively. In the range of 0.5–2.0 m/min welding speed, increasing welding speed progressively enhances the tensile strength of the welded joint. Notably, joints fabricated at a welding speed of 2.0 m/min deliver the maximum tensile strength, equivalent to 98.0% of the base metal. Well-defined dimples are also detected on the corresponding fracture surfaces. A further increase in welding speed leads to a gradual reduction in the tensile strength of the welded joint. It is demonstrated that welding speed acts as a critical process parameter for tailoring the microstructure and mechanical properties of AE-CMT-welded AZ31B magnesium alloy joints. Full article

Multidrug-resistant hypervirulent Klebsiella pneumoniae caused by the improper use of antibiotics has become a major threat to the dairy industry and public health, posing a major challenge to the treatment of bovine mastitis. The resurgence of phage (and its lysozyme therapy) provides a novel strategy to combat such infections. In this study, bovine Klebsiella pneumoniae phage vB_Kpn_B01 nucleic acid was used as a template to successfully achieve the prokaryotic expression of its endolysin. The results of protein gene annotation and prediction showed that Lysin K had the function of lyase, and was designated Lysin K. After optimizing the production conditions, Lysin K could be produced in a soluble form after induction with 0.25 mmol/L IPTG at 37 °C for 16 h, and the concentration was 100 μg/mL after purification. The stability test confirmed that Lysin K can maintain stable antibacterial activity over a wide temperature and pH range. The minimum inhibitory concentration (MIC) of Lysin K was 0.01 μg/mL and remained stable in milk. The Lysin K showed strong lysis activity in vitro and could effectively lyse three types of multidrug-resistant hypervirulent Klebsiella pneumoniae. In the mouse mastitis model induced by Klebsiella pneumoniae KP18 (10⁸ CFU/mL), the intervention of Lysin K can significantly reduce the bacterial load, alleviate the inflammatory response, and restore the normal functional structure of the target mammary gland. In summary, Lysin K has valuable application prospect in the prevention and treatment of bovine mastitis caused by drug-resistant Klebsiella pneumoniae and the development of phage lysin preparations. Full article

Automatic Modulation Classification (AMC) aims to automatically identify modulation types based on the features of received signals, and acts as a vital technique for spectrum sensing, cognitive radio and electronic countermeasures. However, existing methods generally overlook the issue that modulation signals with similar characteristics are prone to confusion. In particular, under strong interference conditions, feature distributions become blurred and class boundaries tend to overlap, further exacerbating misclassification among modulation types with similar characteristics, thereby limiting improvements in classification accuracy and model robustness. To address this challenge, a modulation classification method based on fuzzy sample feature enhancement is proposed. Specifically, a modulation class entropy constraint and a fuzzy sample feature enhancement constraint are introduced to establish a Multi-scale Fuzzy Sample Feature Enhancement Framework (MTFSFEF). Through fuzzy sample selection and feature representation refinement, the proposed framework effectively mitigates feature overlap among fuzzy samples and enhances inter-class separability and discriminability. For $\mathrm{SNR}\ge 0\mathrm{dB}$, MTFSFEF delivers superior average classification accuracies across all three benchmark datasets: $92.82\%$ on RML2016.10a, over $93.43\%$ on RML2016.10b, and exceeding $92.78\%$ on RML2018.01a, outperforming existing methods by up to $2.68\%$, $2.89\%$, and $2.73\%$, respectively. Full article

To address the challenge of balancing food production, groundwater protection, and economic sustainability in agricultural systems, this study developed a novel multi-objective optimization framework integrating an Extreme Learning Machine (ELM)-based surrogate model. An irrigation–fertilization–economy (IFE) model was established to evaluate region-specific agricultural adjustment strategies under four scenarios: baseline adjustment, flexible restructuring, production reduction and profit-oriented expansion scenarios. The optimization results were subsequently used to assess the impacts of agricultural production regulation on groundwater nitrate concentrations in the study area. The results showed that the IFE model consistently favored the conversion from wheat to maize cultivation across all regions, because maize requires less irrigation and fertilizer inputs while maintaining relatively high net profits. However, the optimal strategies varied among regions: Pingdu and Jiaozhou showed greater economic potential for production expansion, whereas regions with lower economic potential were more suitable for reducing high-input crop cultivation. During the 2020–2030 prediction period, nitrate concentrations exhibited substantial interannual variations. Reducing the overall production scale shifted nitrate concentrations approximately 6% closer to the 30–50 mg/L range over the decade, but this limited environmental benefit was accompanied by substantial short-term economic losses. Considering both environmental impacts and economic viability, the optimization results suggest that moderate agricultural expansion could be acceptable provided that environmental burdens are effectively managed. Full article

Vinyl acetate–ethylene copolymer emulsion (VAE) adhesives are widely used in formaldehyde-free wood-based panels and coating systems, but their inherent flammability limits broader application in fire-safety-demanding fields. In this work, fly ash (FA), an industrial solid waste rich in Si- and Al-containing inorganic components, was introduced into a conventional ammonium polyphosphate/melamine/pentaerythritol (APP/MEL/PER) intumescent flame-retardant (IFR) system to prepare flame-retardant VAE emulsion adhesives. The results showed that the incorporation of IFR effectively improved the flame retardancy of VAE, while FA further enhanced the condensed-phase protective effect. The limiting oxygen index (LOI) of VAE/IFR/FA increased to 28.5% from 18.3% for neat VAE, and the sample achieved a UL-94 V-0 rating. Cone calorimetry results showed that the peak heat release rate and total heat release were significantly reduced after flame-retardant modification, accompanied by an increase in residual char. The VAE/IFR/FA sample exhibited the highest char residue and the lowest total smoke production, indicating the positive role of FA in promoting char formation and smoke suppression. The addition of KH403 further regulated the combustion behavior, mainly improving early-stage heat release suppression and fire performance index rather than increasing the final char yield. The KH403-containing formulation also showed improved tensile properties and plywood bonding strength, indicating its potential as a flame-retardant adhesive for wood-based panels. The KH403-containing formulation also showed improved tensile properties and plywood bonding strength, indicating its potential as a flame-retardant adhesive for wood-based panels. SEM-EDS, XPS, Raman, and TG-FTIR analyses confirmed that FA and KH403 contributed to the formation of a phosphorus-rich organic–inorganic hybrid char layer containing Si/Al inorganic structures. This reinforced char layer effectively inhibited heat transfer, oxygen diffusion, and the release of combustible volatiles. This study provides a feasible strategy for developing low-cost flame-retardant VAE adhesives while promoting the high-value utilization of fly ash. Full article

High-pressure ethylene relief is a key safety issue in low-density polyethylene production, where ethylene is typically handled under dense real-fluid conditions. Conventional ideal-gas relief equations may lead to significant errors because thermodynamic properties vary strongly with pressure and temperature. In this study, a real-fluid isentropic relief model was developed using thermodynamic properties obtained from the Reference Fluid Thermodynamic and Transport Properties Database (REFPROP). The critical mass flux was determined by searching for the maximum value along the isentropic expansion path, and the equivalence between the maximum-mass-flux condition and the sonic condition was examined. Four industrial relief cases were compared with proprietary design-calculation outputs. The real-fluid model predicted mass flow rates with deviations of −9.9%, −9.1%, −2.3%, and −1.0%, whereas the ideal-gas model produced larger underpredictions, particularly under ultra-high-pressure conditions. The effects of upstream pressure and temperature on critical mass flux, depressurization paths, speed of sound, and critical pressure ratio were analyzed. A response-surface correlation based on 95 calculated states was developed for preliminary estimation, with all deviations within ±10% over the fitted domain. These results demonstrate the importance of accounting for real-fluid thermodynamics when evaluating high-pressure ethylene relief capacity. Full article

To characterize the cross-scale coupling between macroscopic deformation and microscopic rough-surface contact in metal O-rings, this study proposes a macro–micro contact analysis and leakage flow regime identification method for metal O-ring sealing interfaces. Finite element analysis was employed at the macroscopic scale to obtain the sealing contact width and pressure distribution, while microscopic rough-surface morphology was characterized using fractal theory. Based on asperity contact analysis, the equivalent leakage channel height was determined, and the Knudsen number (Kn) was introduced to identify the fluid flow regime within micro-gaps. The results show that the O-ring cross-section flattens into an elliptical shape under compression, while the contact pressure exhibits a saddle-shaped distribution, and micro-gap leakage channels remain present. As the compression ratio increased from 5% to 25%, the sealing contact width and contact pressure increased, whereas the leakage gap height decreased significantly, resulting in an increase in the Kn values from 0.00176 to 0.045, 0.07, 0.155, and 2.78. Consequently, the flow regime evolved from continuum flow through the transition regime to molecular flow. The findings reveal the cross-scale coupling mechanism between macro–micro contact behavior and leakage flow regime evolution, providing practical guidance for determining the preload level and selecting appropriate leakage models in the engineering design of metal O-ring seals. Full article