Search Results (8,062)

While increasing planting density is a viable strategy for enhancing maize yield, it concurrently elevates the risks of lodging and accelerated leaf senescence due to intensified inter-plant competition, which can ultimately compromise yield stability. A field experiment was conducted in Heilongjiang Province and the study investigated two maize cultivars, JNK728 (Jingnongke 728) and SD5 (Saide 5), under high-density planting conditions (90,000 plants ha⁻¹). The treatments were arranged in a factorial design, incorporating four nitrogen levels (0, 120, 240, and 360 kg N ha⁻¹) in combination with the presence or absence of a chemical regulator (30% diethyl aminoethyl hexanoate · ethephon), with water serving as the control. Results demonstrated that the integration of 240 kg N ha⁻¹ with chemical regulation significantly enhanced photosynthetic capacity—elevating chlorophyll content (SPAD), net photosynthetic rate (Pn), and activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCase) and phosphoenolpyruvate carboxylase (PEPCase)—while improving canopy structure through increased leaf area index (LAI) and optimized light distribution. This strategy also reinforced lodging resistance by optimizing plant morphology (reducing plant height and center of gravity), strengthening basal internodes (increasing stem diameter, dry weight per unit length, and mechanical strength), and promoting accumulation of stem structural components (cellulose, hemicellulose, lignin). Additionally, it facilitated post-anthesis nitrogen translocation to grains and up-regulated key nitrogen metabolism enzymes (glutamate synthetase-GS, glutamate dehydrogenase-GDH, and glutamate-pyruvate transaminase-GPT), thereby boosting nitrogen use efficiency. In contrast, excessive nitrogen (360 kg N ha⁻¹) suppressed these benefits and increased lodging. Consequently, the combined application of 240 kg N ha⁻¹ with chemical regulation achieved the highest yield, proving an effective approach for synergistically enhancing photosynthesis, lodging resistance, and nitrogen utilization in high-density maize systems. Full article

Deep-sea octopuses of the genus Graneledone currently include ten recognized species, yet their phylogenetic relationships remain insufficiently resolved. Here, we provide molecular phylogenetic analyses for eight species based on three mitochondrial markers (16S, COIII, COI) and formally describe a new species from the southeastern Pacific off south-central Chile. Four specimens previously reported lacked evidence necessary for taxonomic validation; in this study, we examine eight additional individuals collected between 436 and 1482 m depth, generating new mitochondrial sequences and proposing an updated phylogenetic hypothesis for the genus. Species delimitation analyses strongly support the recognition of a new species. The newly described octopus is medium-sized, lacks an ink sac, and bears a single series of suckers on arms of similar length. Key diagnostic traits include 43–45 suckers on the hectocotylized (right third) arm, six to seven gill lamellae per demibranch, a VV-shaped funnel organ, and five to seven transverse folds on the ligula. Among all examined characters, the number of opposite suckers provides the most robust morphological distinction from congeners distributed across the Pacific, Atlantic, and Antarctic oceans. Our results highlight the value of integrative taxonomy in resolving species boundaries within Graneledone and reveal previously undocumented diversity in the deep Southeastern Pacific. Continued sampling and molecular analyses will be essential for identifying additional cryptic lineages and refining evolutionary hypotheses for this poorly explored deep-sea octopod lineage. Full article

C. spectabilis (Crotalaria spectabilis), a large leguminous herb species, is widely distributed in tropical and subtropical regions, and it has important ecological and economic values. However, the ecological adaptation of the major leaf functional traits of the species across different habitats and canopy positions remains poorly understood. To address this gap, we sampled leaves from the upper, middle, and lower canopy positions in two common habitats—forest understory and exposed land—and quantified key leaf traits as well as trait–trait relationships to assess differences. The results showed that irradiance and air temperature were significantly lower in the understory than in exposed land, whereas soil moisture and relative humidity were higher, indicating that habitat exerted a stronger influence on leaf traits than canopy position. Canopy position also significantly affected most traits and showed significant interactions with habitat. In exposed land, middle plants exhibited higher individual leaf dry mass (180.049 ± 68.480 mg), larger vein diameter (1.692 ± 0.288 mm), and longer petioles (5.406 ± 0.940 mm). These traits were accompanied by a higher morphology-based leaf dry matter accumulation rate and greater stability of the leaf-trait network, reflecting an adaptive strategy characterized by increased structural investment. In contrast, understory middle leaves were generally longer (13.361 ± 2.714 cm) and wider (7.005 ± 1.464 cm), along with lower photosynthate accumulation rates and weaker trait-network stability, indicating a strategy that enhances light-use efficiency under low-light conditions. In both habitats, leaves from the middle canopy position generally exhibited the highest values for most measured traits. Overall, leaf traits of C. spectabilis and their interrelationships showed considerable plasticity in response to external environmental pressures, primarily differences in light availability. However, from a practical production perspective, minimizing shading is recommended to maximize its ecological benefits. Full article

Hypo-peritectic steels are susceptible to interfacial cracking during thin-slab continuous casting, in which non-metallic inclusions play a critical role. This study systematically investigates the effects of inclusion type and morphology on interface cracking behavior in the steel matrix, with the aim of improving billet shell quality. Hot tensile experiments were conducted using a Gleeble 3800 thermal simulator, and a finite element–based cohesive zone model was developed to simulate inclusion-induced crack nucleation and propagation. The results demonstrate that inclusions markedly influence interfacial stress distribution and damage evolution. The maximum interfacial stresses associated with MnS, Al₂O₃, and composite inclusions are 20.7, 23.4, and 30.5 MPa, respectively. Owing to severe stress concentration at sharp corners, composite inclusions exhibit the earliest crack nucleation at an applied stress of 11.3 MPa and the highest energy dissipation. In all cases, cracks initially nucleate at the location of maximum tensile stress (α = 90°), propagate along the interface, and subsequently penetrate into the matrix, ultimately leading to failure. The strong agreement between numerical simulations and experimental results confirms that angular inclusions accelerate damage by disrupting matrix continuity. These findings provide theoretical guidance for improving hypo-peritectic steel quality through inclusion morphology control during continuous casting. Full article

Sphingolipids are a class of amphipathic lipids characterized by a sphingoid base backbone, which can be classified into glycosphingolipids and sphingomyelins. They exhibit structural complexity and functional diversity, being widely distributed in eukaryotes and some bacterial species. Sphingolipids are important regulators of signal transduction and cellular homeostasis and are involved in numerous biological processes, including cell polarity establishment, energy metabolism, proliferation, and differentiation. However, research on fungal sphingolipids remains limited. This review provides an overview of sphingolipid species, structural features, and their biosynthesis and degradation in fungi. It also summarizes their essential functions in maintaining cell membrane structure, influencing morphological development, pathogenicity, and homeostasis, and participating in apoptosis. Additionally, the potential of antifungal agents targeting the sphingolipid pathway and their application prospects are discussed. Finally, current challenges and future directions in fungal sphingolipid research are highlighted to support the investigation of their mechanisms and the development of antifungal therapies targeting sphingolipid metabolic pathways. Full article

Despite advances in high-resolution topographic survey technologies, abstracting static 3D data into physically meaningful indicators remains critical for river management. This study introduces a geometric moment technique to reflect river curvature and hydraulic characteristics within an integrated framework. Analysis was conducted on a reach of the Nakdong River using first-, second-, and third-order moments, W/D ratios, asymmetry indicators, and D50 data. Key findings are: First, the moment-based approach precisely quantified asymmetric variations and localized bed changes by utilizing centroid deviation (M1), dispersion (M2), and mass bias (M3), addressing the limitations of traditional average-based indices. This effectively transforms vast 3D datasets into “compressed records” for tracing hydraulic drivers. Second, sinuosity (S) analysis revealed that reaches with higher curvature (S ≥ 1.5) exhibited intensified variability in third-order moments and asymmetry due to imbalanced hydraulic forcing. Specifically, the horizontal misalignment between the velocity core and the thalweg was identified as a key mechanism driving geometric imbalance in curves. Third, a W/D-asymmetry quadrant analysis categorized reach-scale morphological types and identified hydraulically vulnerable zones. By integrating sectional geometry, velocity distribution, and sinuosity into a unified system, this study provides a quantitative framework for scientific river management and decision-making. Full article

To address the inherent defects in the fabrication of AlCrN titanium alloy coatings and enhance interfacial bonding strength as well as tribological performance, an AlCrN coating was employed as an absorption layer and subjected to laser shock processing to form an AlCrN/TC4 transition layer. Subsequently, a secondary AlCrN coating was deposited to construct a gradient coating architecture. The surface and cross-sectional morphologies and elemental distributions under varying laser energies were systematically investigated, and the influence of laser energy on the adhesion and wear resistance of the gradient coatings was analyzed. The results demonstrate that with increasing laser impact energy, the thickness of the AlCrN/TC4 transition layer gradually decreases from 3.75 μm to 1.32 μm, accompanied by significant changes in elemental distribution across the surface and cross-section. The interfacial bonding strength of the gradient coating increases substantially from 13.6 N to 43.3 N, while the average friction coefficient rises from 0.436 to 0.507. Concurrently, the wear track depth is reduced, and the wear rate decreases from 86.46 × 10⁻⁵ mm³/(N·m) to 7.67 × 10⁻⁵ mm³/(N·m). Laser shock peening promotes elemental diffusion, enabling the formation of a diffusion-aided interlayer. The incorporation of this diffused zone facilitates the successful construction of a high-quality TC4 titanium alloy gradient coating, effectively broadening the film–substrate interface, enhancing surface hardness, and significantly improving both interfacial adhesion and wear resistance. Full article

Background: Medicinal plants used in traditional Mexican medicine represent a valuable source of bioactive compounds with potential anticancer activity. Beyond cytotoxic potency, selectivity toward cancer cells over normal cells is a critical toxicological parameter for identifying safer therapeutic candidates. This study aimed to evaluate the selective cytotoxic and antiproliferative effects of extracts from four Mexican medicinal plants across human cancerous and non-cancerous cell lines. Methods: Hexane, acetone, and methanolic extracts from Semialarium mexicanum, Eryngium heterophyllum, Piper auritum, and Cochlospermum vitifolium were evaluated in a panel of human cancer cell lines and non-tumoral models, including primary human uterine fibroblasts (HUFs). Cytotoxicity was assessed after 48 h of treatment using increasing extract concentrations, and selectivity indices were calculated. Cell cycle distribution and nuclear morphology analyses were performed to explore antiproliferative effects. Additionally, GC–MS-based chemical profiling was conducted on selected extracts to obtain a tentative characterization of major bioactive constituents. Results: The extracts exhibited differential cytotoxic profiles depending on plant species and solvent polarity. The hexane extract of Semialarium mexicanum showed the highest cytotoxic potency and selectivity toward cervical cancer cells, with half-maximal inhibitory concentration (IC₅₀); values of 15.9 ± 1.8 µg/mL and 17.2 ± 2.8 µg/mL in HeLa and SiHa cells, respectively, and selectivity index (SI) values > 5 when compared with primary human uterine fibroblasts (HUF). Extracts of Eryngium heterophyllum displayed moderate cytotoxic activity (IC₅₀ = 20–30 µg/mL in HeLa cells) with intermediate selectivity, whereas Cochlospermum vitifolium showed solvent-dependent effects and Piper auritum exhibited limited cytotoxicity. Cell cycle analysis revealed an increased sub-G1 population, and nuclear morphology assays demonstrated chromatin condensation and fragmentation in cancer cells, supporting an antiproliferative mechanism. GC–MS analysis of the hexane extract of Semialarium mexicanum suggested the presence of triterpenoid-related and other lipophilic compounds potentially associated with its selective anticancer activity. Conclusions: These findings provide in vitro evidence of selective anticancer activity of Mexican medicinal plant extracts and establish a basis for future mechanistic studies medicinal plant extracts and lay the groundwork for future mechanistic investigations. Full article

The success of acid stimulation in tight carbonate reservoirs relies on the formation of non-uniform etching on fracture walls. However, existing research on the influence of the fracture surface morphology on non-uniform etching and fracture conductivity predominantly employed non-replicable tensile fracture surfaces. Previous studies were unable to use identical fracture surfaces to conduct single-factor analysis and clarify the impact of roughness. This study utilized digital engraving technology to fabricate multiple artificial carbonate rock samples with a homogeneous lithology and completely consistent fracture surface morphology. Using the Triangular Prism Method (TPM), the initial fracture roughness of the rock samples was decomposed into large-scale waviness and small-scale unevenness. Through controlled injection parameters, single-factor acid etching experiments were conducted. For the first time, the effects of large-scale waviness and small-scale unevenness on acid etching were investigated, along with the influences of the acid injection rate and injection time. The existence of an optimal injection rate and an optimal injection time was clarified. The results demonstrate that the engraved carbonate samples’ surfaces exhibit good consistency with the original natural fracture surfaces. The acid solution acts to shave the “peaks” and deepen the “valleys” of rough fractures. The large-scale waviness characteristics of the initial rough surfaces determine the overall post-etching morphology, leading to poor surface contact within the fracture. This is the primary reason for the high fluid flow capacity of acid-etched fractures under low closure stresses. However, the small-scale unevenness characteristics of the initial rough surfaces determine the formation and the distribution of small protruding support points on the post-etching surface. This is the primary reason for the retention of high conductivity in acid-etched fractures under high closure stresses. An increase in the acid injection rate or acid injection time does not lead to a linear decrease in linear roughness, surface mismatch, or fracture aperture. A critical acid injection rate or critical acid injection time exists. Optimizing the injection rate or time can achieve an ideal etching morphology—the protrusions formed by punctate etching enable the fractures to maintain a certain level of conductivity even under a high closure stress of 55.2 MPa, while channel etching can increase the conductivity under high closure stress by 20–25%, providing a key direction for optimizing acid etching effects. Full article

Type 2 diabetes mellitus (T2DM) is a globally prevalent chronic metabolic disorder that poses severe public health risks. Synthetic hypoglycemic agents are susceptible to inducing adverse reactions, thus driving the development of natural, safe and highly effective plant-derived hypoglycemic active compounds as a research hotspot. Inhibiting the activity of α-glucosidase and α-amylase represents an effective strategy to regulate postprandial blood glucose levels. This study investigated the synergistic hypoglycemic activity of a composite (PS-PP) formed by polysaccharide (PS) and polyphenols (PP) from Ziziphus jujuba Mill. cv. Muzao and elucidated the structural basis underlying this synergistic effect. First, MPS and MPP were isolated and purified, followed by the in vitro assembly to prepare PS-PP. The hypoglycemic activities of MPS, MPP and MPS-PP were evaluated via in vitro enzyme inhibition assays, while structural characterization was conducted using GPC-MALLS, FT-IR and SEM techniques. Results demonstrated that PS-PP exerted the strongest activity under optimal conditions (0.75 mg/mL concentration, pH 4.0, 1:2 mass ratio), with IC₅₀ values of 1.14 μg/mL and 0.82 μg/mL against the two enzymes, which were superior to those of polysaccharides (15.10 and 36.06 μg/mL) and polyphenols (1.18 and 46.24 μg/mL). Structural analysis revealed that the interaction between PS and PP was primarily mediated by hydrogen bonds. PS-PP exhibited significant differences from single-component compounds in molecular weight distribution, functional group binding and surface morphology. These structural alterations were identified as the key factors contributing to its enhanced hypoglycemic efficacy. This study clarifies the synergistic hypoglycemic mechanism of MPP-PS and lays a scientific foundation for the development of natural hypoglycemic preparations and functional foods. Full article

Aging and Alzheimer’s disease (AD) are associated with profound changes in glial cell morphology and signaling. This study investigates the three-dimensional morphology of microglia and the intracellular localization of phosphorylated SMAD proteins as downstream effectors of transforming growth factor β (TGF-β) signaling in the amyloid precursor protein and presenilin-1 (APP/PS1) transgenic mouse model of Alzheimer’s disease. Using confocal microscopy and Simple Neurite Tracer software, we reconstructed and quantitatively analyzed glial cell morphology in aged wild-type and APP/PS1 mice. Immunofluorescence staining revealed altered pSMAD2 distribution in microglia, suggesting impaired canonical TGF-β signaling. Our findings indicate a disturbed glial morphology and dysfunctional TGF-β signaling cascade in the APP/PS1 model, underlining their potential role in Alzheimer’s disease pathogenesis. Full article

This paper proposes a valorization approach for solid lavender residue, a by-product of the essential oil industry. The biomass residue was carbonized at atmospheric pressure and two temperatures (450 °C and 650 °C), followed by solvothermal modification with zinc ions (Zn²⁺, 3 and 5 mmol). The effects of temperature and Zn²⁺ incorporation on the elemental composition and morphology of the resulting biochar were examined using X-ray Fluorescence (XRF), Fourier Transform Infrared (FTIR) spectroscopy, and Scanning Electron Microscopy/Energy-Dispersive X-ray Spectroscopy (SEM/EDS) analyses. The applied Zn²⁺ modification was effective at both concentrations for the biochar obtained at both carbonization temperatures. However, a more uniform metal ion distribution was observed at 3 mmol, while at 5 mmol, a partial particle agglomeration occurred. Progressive degradation of the O–H, C=O, and C–O groups with increasing temperature and the presence of Zn–O-related interactions was observed. The results demonstrated consistent and reproducible trends, suggesting that controlled carbonization combined with Zn²⁺ incorporation can convert lavender residues into modified carbonaceous materials. Full article

As the raw material for tea making, the quality of fresh tea leaves directly affects the quality of finished tea. Traditional manual sorting and machine sorting struggle to meet the requirements for high-quality tea processing. Based on machine vision and deep learning, intelligent grading technology has been applied to the automated sorting of fresh tea leaves. However, when faced with machine-picked tea leaves, the characteristics of complex morphology, small target recognition size, and dense spatial distribution can interfere with accurate category recognition, which in turn limits classification accuracy and consistency. Therefore, we propose an enhanced YOLOv12 detection framework that integrates three key modules—C3k2_EMA, A2C2f_DYT, and RFAConv—to strengthen the model's ability to capture delicate tea bud features, thereby improving detection accuracy and robustness. Experimental results demonstrate that the proposed method achieves precision, recall, and mAP@0.5 of 81.2%, 90.6%, and 92.7% in premium tea recognition, effectively supporting intelligent and efficient tea harvesting and sorting operations. This study addresses the challenges of subtle fine-grained differences, small object sizes, variable morphology, and complex background interference in premium tea bud images. The proposed model not only achieves high accuracy and robustness in fine-grained tea bud detection but also provides technical feasibility for intelligent fresh tea leaves classification and production monitoring. Full article

Fe-rich phases are unavoidable intermetallic compounds in aluminum alloys, particularly in recycled aluminum. Their needle-like morphology not only impairs the mechanical performance of the alloy by disrupting the continuity of the matrix but also significantly reduces the allowable addition of recycled aluminum materials. Based on this, this study focuses on the Al-7Si-0.35Mg-0.35Fe alloy with a high Fe content. The Cr was introduced to modify the characteristics of the Fe-rich phase, and the microstructural evolution and mechanical properties of the aluminum alloy with different Cr content (0–0.25 wt.%) were investigated. Experimental results show that the secondary dendrite arm spacing of the alloy is significantly refined after Cr addition. Meanwhile, the Fe-rich phase gradually transitions from β-Al₅FeSi with needle-like morphology to α-Al₁₅(Fe,Cr)₃Si₂ with short rod-like or blocky morphology as the Cr content increases. Notably, the Fe-rich phase in the 0.20Cr alloy exhibits an approximately 65% increase in sphericity and an 84% reduction in equivalent diameter compared to those in the 0Cr alloy. The morphological blunting and dispersed distribution of Fe-rich phases lead to a broad effective Cr addition range of 0.05–0.20 wt% in the alloy. Among them, the 0.20Cr alloy exhibited the best comprehensive mechanical properties, with its ultimate tensile strength and elongation approximately 19% and 107% higher than those of the 0Cr alloy, respectively. Furthermore, the fracture morphology and the relationship between the Fe-rich phase and microcracks in Al-7Si-0.35Mg-0.35Fe alloys with different Cr contents were also analyzed. Full article

Hydrophobic bioactive compounds such as lutein exhibit poor water solubility and are prone to degradation. Liposomal delivery systems can enhance the solubility and physicochemical stability of lutein (LUT). Liposomes are primarily composed of phospholipids and cholesterol. Since phytosterol ester can reduce cholesterol levels and improve the performance of liposomes, this study used phytosterol oleate ester (POE) as a cholesterol substitute in the preparation of liposomes for delivering LUT (LUT-P-Lip). The physicochemical properties, microstructure, storage stability, antioxidant characteristics, and intermolecular interactions of the liposomes at different LUT concentrations were investigated. The results demonstrated that LUT-P-Lip had a size range of 50–100 nm, with intact morphology and uniform distribution. In vitro studies showed that LUT-P-Lip significantly enhanced the storage stability and antioxidant activity of LUT. The analysis of intermolecular interactions revealed that the enhanced stability was mediated by an increased number of hydrogen bonds and modulation of membrane fluidity. In conclusion, replacing cholesterol with POE during liposome formation enhances both the stability and antioxidant activity of the resulting liposomes. Full article