Search Results (10,624)

Objectives: This study aims to provide a theoretical basis for a deeper understanding of the transcriptional regulatory network underlying the formation of Primula forbesii floral scent, and also offers important genetic resources for the molecular improvement of floral scent traits in Primula species. Methods: Using the P. forbesii cultivar ‘Pink violet’ as experimental material, we cloned PfbHLH131 and analyzed its expression pattern. We also validated its function via virus-induced gene silencing (VIGS) and used gas chromatography–mass spectrometry (GC-MS) to analyze changes in floral aroma components in silenced plants. Additionally, we detected the expression levels of key structural genes involved in floral aroma biosynthesis in silenced plants via qRT-PCR to elucidate the regulatory role of PfbHLH131 in the biosynthesis of P. forbesii floral aroma. Results: The cloned PfbHLH131 open reading frame is 922 bp in length, encoding a total of 307 amino acids, and contains a bHLH_AtBPE_like domain characteristic of the bHLH gene family. Quantitative real-time PCR (qRT-PCR) revealed that PfbHLH131 is highly expressed in floral organs, peaking during full bloom. Subcellular localization studies indicated that it is localized to the nucleus. VIGS-mediated transient silencing of PfbHLH131 significantly reduced the release of terpenoid and phenylpropanoid floral odor compounds and suppressed the expression of multiple key structural genes in both synthetic pathways. Conclusions: PfbHLH131 is a positive regulator of scent biosynthesis in P. forbesii. Full article

This work describes an efficient and environmentally friendly method for the synthesis of silver-based nanostructures through a green route using Aloe vera extract as a reducing agent, silver nitrate (AgNO₃) as a precursor, and polyvinylpyrrolidone (PVP, 10 kDa molecular weight) as a stabilizing agent. The formation of these structures was supported by UV–Vis spectroscopy, where a surface plasmon resonance (SPR) band was observed between 425 and 460 nm. Scanning electron microscopy revealed predominantly spherical features in the 300–500 nm range; however, the distinction between primary nanoparticles and aggregates cannot be conclusively established from SEM alone. EDX analysis indicated a silver content of 59.96 wt%. Antibacterial assays performed in Z8 medium demonstrated a reduction in cyanobacterial growth with increasing dosage, with complete inhibition observed at ≥20 $\mu$L (nominal MIC = 1.77 mg mL⁻¹, based on precursor estimation). Total dissolved solids and absorbance measurements exhibited a decreasing trend with increasing concentration (effect size = 0.87, $p<0.001$), supporting an inhibitory effect under the tested conditions. These findings suggest potential antibacterial activity. However, this study should be considered exploratory, and further work is required to elucidate the underlying mechanisms. Full article

To explore potential strategies for improving the applicability of cyanidin-3-O-glucoside (C3G) and to avoid the health risks associated with the in vivo accumulation of aluminum by intake of traditional aluminum-based lake pigments, food-grade CaCO₃ was used as a matrix to prepare two types of edible lake pigments, namely C3G-CaCO₃ and MA-CaCO₃, via coprecipitation method using purified cyanidin-3-O-glucoside (C3G) and non-purified mulberry anthocyanins (MA). The effect of pH on adsorption was systematically investigated, and various characterization methods were used to analyze the physicochemical properties and formation mechanism of lake pigments. The results showed that pH 9.5 was the optimal condition for CaCO₃ to adsorb MA. The introduction of C3G altered the particle size, surface charge, and other characteristics of CaCO₃ without changing its calcite crystal form. The adsorption of MA and C3G on the CaCO₃ surface was multilayer physical adsorption, dominated by the Freundlich model. The isothermal adsorption results showed that CaCO₃ exhibited a higher adsorption capacity for C3G than for MA at equivalent equilibrium concentrations, demonstrating C3G’s superior binding affinity. C3G primarily binds to calcium carbonate through surface adsorption, with possible partial diffusion of molecules into the matrix, without forming new chemical bonds, and slightly regulated the thermal stability of CaCO₃. This study successfully constructed a lake pigment system based on CaCO₃, systematically elucidated its adsorption behavior and structural characteristics toward anthocyanins, and provided a material foundation for the further application of this type of carrier in the food sector. Full article

Multi-scale vortex structures constitute the intrinsic skeleton of turbulent flows and govern the energy cascade process in oceanic turbulence. Elucidating their evolutionary dynamics is crucial for understanding turbulent mixing and transport. In this study, we develop an innovative Energy Cascade Multilayer Directed Network (ECMDN) framework grounded in complex network theory to directly characterize nonlinear energy coupling pathways and directional transfers among multi-scale vortices in real marine environments. By integrating multi-parameter fusion node definitions, multi-scale interaction detection, and energy transfer direction identification, the ECMDN reconstructs the nonlinear turbulent system into a topologically interpretable structure. The emergent network properties enable quantitative characterization of intermittency and inhomogeneity in the energy cascade, offering new insights into vortex interactions and cross-scale energy transfer mechanisms. Compared with conventional cascade diagnostics including spectral flux, third-order velocity structure functions, multifractal analysis and shell models that require homogeneity and local equilibrium assumptions and only output global averaged energy flux, the proposed ECMDN multilayer network retains point-wise depth coordinates of each vortex interaction, separates directed forward/inverse energy edges, and quantifies intermittency via topological metrics. Analysis of the single Shenhu thermocline shear segment demonstrates these differentiated analytical capabilities of the proposed framework. Application to shear measurements from the Shenhu Sea reveals the simultaneous occurrence of forward and inverse energy cascades, manifesting a synchronous dual-energy-cascade pattern. This indicates that vortices at a given scale can concurrently transfer energy to larger- or smaller-scale structures and receive energy from larger- or smaller-scale counterparts during the cascade process. Our findings observe a typical synchronous dual-energy-cascade pattern in the strong thermocline of the Shenhu Sea, providing a novel theoretical and methodological framework for investigating the spatiotemporal evolution of stratified ocean turbulent mixing and advancing our understanding of geophysical fluid dynamics. Full article

Medicinal plants are being investigated as a source of compounds with biological activities related to diabetes. The antidiabetic properties of the plant Carica papaya have been reported in experimental models. This study aimed to evaluate the phytochemical composition, antioxidant activity, and inhibitory activity of extracts from C. papaya leaves against α-glucosidase and pancreatic lipase. Plant material was collected in Tabasco, Mexico, and extracted by sequential maceration with solvents of increasing polarity: hexane, dichloromethane, methanol, and methanol:water. The extracts were fractionated by column chromatography, and the most active fractions were selected for further purification. The phytochemical identification of the active compounds was performed, and their structures were elucidated using spectroscopic and spectrometric techniques. The methanolic extract, rich in phenols and flavonoids, showed the highest antioxidant capacity (DPPH: 8.99 mmol TE/g; ABTS: 35.94 mmol RE/g; FRAP: 48.62 mmol Fe²⁺/g). The hydroalcoholic extract exhibited α-glucosidase inhibitory activity (38.44%), and bioassay-guided fractionation led to the identification of clitorin. The dichloromethane extract showed pancreatic lipase inhibition (52.2%), and the most active fraction contained loliolide. These findings demonstrate that C. papaya leaves contain bioactive compounds with antioxidants and digestive enzyme inhibitory activities, suggesting they could be candidates for further research in the management of diabetes. Full article

Perforated vortex generators have been widely investigated as a passive heat transfer enhancement technique due to their ability to modify local flow structures through perforation-induced bleed flows. However, their thermo-hydraulic performance is strongly dependent on geometric and flow conditions, and a consistent enhancement effect has not been universally observed. In this study, the mechanism of heat transfer enhancement as well as flow behaviors associated with perforation-induced bleed flows are elucidated through an analysis of the generation and interference behaviors of mixed coherent structures induced by vortex generators punched with multi-holes (PMHVGs). The results showed that the beveled edges of the PMHVGs are responsible for initiating the formation of mixed coherent structures, while local fluid-pressure gradients are identified as the primary driving factor behind their development. Once formed, the perforation-induced bleed flows exert interference on other coherent structures, thereby reducing both their formation intensity and interaction strength. After their generation, the mixed coherent structures contribute to thermal energy transport within the flow through their near-wall ejection and sweep motions. Full article

Emotional and behavioral problems (EBPs) experienced by children have become an important global health issue requiring immediate attention. Previous studies have shown that parental neuroticism is associated with EBPs in children. However, the mechanisms underlying this association have yet to be fully elucidated. This study examined the relationship between parental neuroticism and preschoolers’ EBPs, focusing on the mediating role of parental emotional distress (e.g., anxiety, depression, and somatization). In addition, to gain a deeper understanding of children’s emotional and behavioral difficulties, this study constructed a comprehensive network of preschoolers’ EBPs to investigate the interconnections among individual symptoms. A total of 1216 Chinese families (M_{children age} = 4.46 years; 47.6% girls) participated in this study, completing the Chinese Big Five Personality Inventory, Brief Symptom Inventory, and Strengths and Difficulties Questionnaire. Data analysis was conducted using structural equation modeling (SEM) and network analysis. The results showed that parental neuroticism was positively associated with children’s EBPs, and this relationship was partially mediated by parental emotional distress. “Constantly fidgeting or squirming”, “stealing from home, kindergarten, or other places”, “often unhappy‚ depressed or tearful”, and “many fears‚ easily scared” emerged as the most central symptoms in the network of EBPs. These findings hold significant implications for enhancing well-being among parents and their preschool children, suggesting that parents should prevent the spread of negative emotions such as anxiety and depression. Timely, targeted interventions focusing on central symptoms of EBPs are essential for promoting children’s mental well-being. Full article

Chalcopyrite and molybdenite exhibit similar surface wettability and high floatability, which has long hindered their efficient and selective separation in mineral processing. In this work, the novel chalcopyrite depressant 2-mercapto-5-benzoimidazole sulfonate dihydrate (2MBI5SA) was investigated for its effect on the flotation behavior of chalcopyrite and molybdenite. Compared with the conventional depressant sodium sulfide (Na₂S), 2MBI5SA exhibited stronger selective depression toward chalcopyrite; under conditions yielding a Mo recovery of 81.46% and a Mo grade of 4.46%, the Cu recovery decreased to 13.03%. To clarify the origin of this selectivity, interfacial properties were systematically characterized using adsorption measurements, contact angle measurements, zeta potential measurements, FTIR, XPS, and SEM-EDS, and the adsorption mechanism was further elucidated using SCC-DFTB calculations. The results demonstrate that 2MBI5SA chemisorbs onto the chalcopyrite surface via bidentate coordination, forming a stable adsorption layer that effectively suppresses chalcopyrite flotation. Moreover, structure−function relationship analysis confirmed that introducing hydrophilic and ionizable functional groups into the collector framework can convert a collector into a selective depressant, thereby providing new insights into the rational design of selective organic depressants with potential environmental advantages over conventional highly toxic inorganic depressants. Full article

White-nose syndrome (WNS), caused by the psychrophilic fungus Pseudogymnoascus destructans, poses a severe threat to wild bat populations. Caves serve as unique microecosystems. Exploring antagonistic microorganisms and their volatile antifungal compounds within these native environments has emerged as a promising ecological control strategy. In this study, we isolated four antagonistic bacterial strains from bat cave soil that completely inhibit P. destructans. Additionally, we identified benzaldehyde (BzH) and 2,5-dimethylpyrazine (2,5-DMP) as their primary antifungal volatile organic compounds (VOCs). Combined physiological, biochemical, and multi-omics analyses revealed that these two VOCs disrupt the structural integrity of the fungal cell wall and membrane. This disruption triggers abnormal energy metabolism and compensatory ATP accumulation, leading to a significant intracellular burst of reactive oxygen species and the impairment of primary antioxidant defenses. This sustained oxidative stress causes irreversible DNA damage, endoplasmic reticulum stress, and basal metabolic dysfunction. Consequently, this cascade induces apoptosis and significantly downregulates the expression of essential virulence genes. In conclusion, this study systematically elucidates the molecular network through which VOCs released by cave soil microorganisms antagonize P. destructans. These findings provide a theoretical foundation and candidate intervention molecules for the contactless biocontrol of WNS. Full article

Slope stability has consistently been a critical concern in mountainous road sections, with precipitation being the most significant factor precipitating slope instability. This study aims to elucidate the mechanism of slope instability under precipitation conditions and the extent of the impact of internal disaster-causing factors. To achieve this objective, a numerical simulation analysis method combining GeoStudio2018R2 and FLAC3D7.0 software was employed to conduct a comprehensive analysis of an unstable slope in Xinjiang. Regarding research methodology, cyclic precipitation and seasonal snowmelt were considered as external influencing factors. Initially, a two-dimensional model was constructed using GeoStudio software to analyze the spatial and temporal variations in pore water pressure and moisture content within the slope, elucidating their dynamic characteristics at different temporal and spatial scales. Subsequently, a three-dimensional numerical model was established using FLAC3D software to conduct a detailed analysis of the stress–strain state of the slope under various conditions, thereby obtaining disaster parameters such as displacement and sliding velocity in different directions. Through further comparison and verification of the overall stability analysis results of the slope obtained from both software packages, it was observed that they exhibited a consistent trend. The research findings indicate that under conditions of high-intensity short-term precipitation, the safety factor of the slope decreases to the lowest level, potentially leading to shallow landslides with smaller displacement but faster sliding velocity. Conversely, seasonal snowmelt and long-term localized precipitation have a more profound impact on the internal structure of the slope, with the sliding zone potentially penetrating into the deep bedrock. Although the occurrence frequency is low, the impact range is extensive. By combining two-dimensional and three-dimensional analyses, a comprehensive assessment of the different disaster-causing factors of the slope was conducted, enhancing the accuracy of the analysis results. The research findings provide a scientific basis and reference value for the formulation of subsequent slope protection and monitoring plans. Full article

In this study, Apocynum venetum was employed as the raw material to optimize protein extraction and enzymatic hydrolysis processes for the preparation of highly active angiotensin-converting enzyme (ACE)-inhibitory peptides, achieving an ACE inhibition rate of 92.34%. Multispectral analyses and microstructural characterization demonstrated that enzymatic hydrolysis induced the unfolding of protein secondary structures, resulting in a looser and more porous morphology enriched with characteristic amino acids. A total of 2567 peptide sequences were identified by LC–MS/MS, among which 18 potential bioactive peptides were screened. Molecular docking analysis revealed that these peptides interact with the active site of ACE primarily through hydrogen bonding and hydrophobic interactions, with WLRDFL exhibiting the strongest binding affinity. This study systematically elucidates the structural characteristics and antihypertensive molecular mechanisms of ACE-inhibitory peptides derived from Apocynum venetum, providing both theoretical insights and experimental support for the development of natural antihypertensive functional foods and the high-value utilization of this plant. Full article

The protective effect of Compound terminalia chebula extract (HL) against colonic injury induced by Porcine epidemic diarrhea virus (PEDV) infection in neonatal piglets remains unclear. This study aimed to evaluate the mitigating effects of HL on PEDV-induced colonic injury and elucidate the underlying mechanisms. Eighteen 7-day-old Duroc × Landrace × Large White piglets (2.58 ± 0.05 kg) were randomly assigned to three groups (n = 6/group): CON (blank control), PEDV (infected), and HL + PEDV (HL-supplemented + infected). The 11-day trial included 3 days of acclimatization (days 0–3) and an 8-day experimental period (days 4–11). HL (10 mg/kg BW) was orally administered daily to the HL + PEDV group. On day 8, PEDV and HL + PEDV groups were challenged with 3 mL PEDV (3 × 10⁶ TCID₅₀/mL), while CON received Dulbecco’s Modified Eagle Medium (DMEM). All piglets were euthanized on day 11 for colonic tissue collection. Results indicated that PEDV infection induced colonic injury, manifested by a significant increase in crypt depth and disruption of intestinal homeostasis. This was evidenced by impaired barrier integrity (upregulation of matrix metalloproteinase-7 gene [MMP7] and matrix metalloproteinase 13 gene [MMP13], mucus disorganization (elevation of mucin 5AC gene [MUC5AC]), oxidative stress (reduced catalase [CAT] activity and increased malondialdehyde [MDA] levels in serum and colon), and inflammation (upregulation of regenerative islet-derived protein 3γ gene [REG3G], S100 calcium-binding protein A8/A9 gene [S100A8/A9], and interleukin-1β gene [IL-1β]). Additionally, PEDV impaired colonic ion transport by downregulating calcium channel genes (Transient Receptor Potential Cation Channel Subfamily V Member 6 gene [TRPV6], Transient Receptor Potential Cation Channel Subfamily M Member 6 gene [TRPM6]). Notably, HL supplementation effectively reversed these adverse effects. HL restored colonic morphology, increased CAT activity, reduced MDA accumulation, and suppressed inflammatory gene expression. Furthermore, HL modulated the expression of genes involved in water and ion transport upregulating Aquaporin 7 gene (AQP7), Chloride Channel Accessory 4 gene (CLCA4), Sodium-Hydrogen Exchanger 3 gene (NHE3), Transient Receptor Potential Vanilloid 6 (TRPV6), and Transient Receptor Potential Melastatin 6 gene (TRPM6) and significantly inhibited PEDV replication, as indicated by the downregulation of the transcription levels of PEDV membranegene (M), nucleocapsid gene (N), and spike gene (S). Taken together, HL alleviates PEDV-triggered colonic tissue damage in suckling piglets via improving colonic antioxidant capacity, mitigating inflammatory response, partially regulating intestinal barrier and ion/water transport-related genes, and downregulating the transcription of PEDV structural genes at molecular and histological levels. Full article

Global atmospheric N₂O concentrations have risen to 335 ppb, with agricultural soils serving as a major emission source and rice paddies accounting for approximately 11% of agricultural N₂O emissions. Rice–crab co-culture has been widely adopted because of its potential to increase and stabilize crop yields; however, the underlying mechanisms of N₂O mitigation and the synergistic effects of crab bioturbation with water and nitrogen management remain unclear. Therefore, in this study, we conducted a two-year field experiment in Zhaodong, Heilongjiang Province, China, to elucidate the N₂O mitigation effects of rice–crab co-culture under water and nitrogen regulation and the associated driving mechanisms. The results showed that rice–crab co-culture significantly reduced N₂O emissions. Specifically, the N₂O flux decreased by 19.9%, while cumulative N₂O emissions decreased by 19.8%. Under the combined regulation of water and nitrogen management, the mitigation effect on N₂O emissions was further enhanced, with a reduction of up to 30.8%. Regarding environmental factors, crab activity combined with shallow wet irrigation reduced soil water content and increased surface temperature. These changes promoted the transformation of nitrogen from inorganic forms to microbially assimilable forms, increasing the microbial nitrogen content by approximately 29.5%. Meanwhile, soil enzyme activities changed significantly: the activities of urease, sucrase, and protease increased, whereas nitrate reductase activity decreased. Structural equation modeling showed that the indirect effect of management practices was much greater than the direct effect, accounting for 63% of the total effect. Nitrogen transformation was the core mitigation pathway, characterized by the conversion of inorganic nitrogen into microbial biomass nitrogen, which reduced substrate availability for nitrification and denitrification. Enzyme activity regulation served as a secondary pathway, mainly through the inhibition of nitrate reductase activity. Overall, the rice–crab system achieved sustained N₂O reduction by improving soil aeration and jointly regulating substrate limitation and weakening nitrogen transformation capacity. Full article

Microalgae-based regulation is increasingly recognized as an eco-friendly strategy for improving water quality and nutrient management in intensive aquaculture systems. Although its effects on bacterial communities have been extensively investigated, its ecological impacts on higher trophic levels—particularly eukaryotic plankton communities across different size fractions—remain poorly understood. In this study, two indigenous microalgae species, Nannochloropsis oculata and Thalassiosira weissflogii, were inoculated into shrimp rearing water to elucidate the dynamics and interactions among microalgae, nutrient factors, and eukaryotic plankton communities across the small-sized (0.22–3 μm) and large-sized (>3 μm) fractions. The results revealed significant differences in the composition and diversity of both plankton size fractions under different microalgae treatments. Partial least squares path modeling indicated that microalgae influenced plankton communities both directly and indirectly through nutrient-mediated pathways. According to the neutral community model, microalgae inoculation was associated with an increased contribution of deterministic processes to community assembly. Variance partitioning further revealed that the large-sized community was primarily governed by microalgae, whereas the small-sized community was mainly shaped by rearing time, indicating size-dependent assembly mechanisms. The average variation degree and coefficient of variation, combined with effect-size analyses, indicated that N. oculata inoculation was associated with higher short-term community stability, an effect most pronounced in the large-sized fraction. Overall, these findings demonstrate that microalgal inoculation modulates the structure, assembly processes, and short-term stability of eukaryotic plankton communities, providing new insights into size-dependent, microalgae-driven assembly mechanisms and their potential to stabilize plankton communities for sustainable aquaculture management. Full article

Background: Bone tissue is a dynamic structure capable of continuous remodeling; however, its regenerative capacity is limited in critical-size defects, often requiring the use of bone grafting procedures. Available grafting materials present inherent limitations, highlighting the need for strategies that can enhance regenerative outcomes. Hyaluronic acid (HA) has been proposed as a promising adjunctive agent because of its biological properties, including anti-inflammatory and pro-angiogenic effects. Objective: To systematically evaluate the available clinical evidence regarding the effects of HA as an adjunct in bone regeneration procedures, including alveolar ridge preservation, ridge augmentation, and maxillary sinus elevation. Materials and Methods: A systematic search was conducted in the PubMed, ScienceDirect, Google Scholar, and Wiley Online Library databases for studies published within the last 10 years. Clinical studies involving adult patients were included if they evaluated the local application of HA, regardless of formulation, and reported quantitative clinical, radiographic, histological, or histomorphometric outcomes related to bone regeneration. Results: Of the 728 records initially identified, 10 studies met the eligibility criteria and were included in the qualitative synthesis. Discussion: Overall, the available evidence suggests that HA may positively influence bone regeneration outcomes. The most consistent benefits were observed in alveolar ridge preservation and ridge augmentation procedures, including increased new bone formation, improved bone density, enhanced bone maturation, and reduced dimensional bone loss. In contrast, findings regarding maxillary sinus augmentation were less consistent. Conclusions: HA appears to be a promising adjunct in bone regeneration procedures. However, the current evidence remains limited and is primarily based on clinical outcomes, providing insufficient mechanistic data to fully elucidate its biological effects. Further well-designed randomized controlled trials with standardized protocols are required before definitive clinical recommendations can be established. Full article