Search Results (1,986)

Natural rubber biosynthesis is catalyzed by a unilamella membrane-bound heterologous complex with multiple different subunits (rubber transferase, RTase). Two substrates and divalent metal cation activators are required, and their concentrations affect biosynthetic rate and polymer molecular weight. Rate, molecular weight, and complex stability are highly sensitive to Mg²⁺ and Mn²⁺ concentration, but studies are challenging because methods to control ion concentration may dislodge the elongating rubber polymers from the RTase complexes, halting synthesis and producing low-molecular-weight polymer. Here, programmable chemical actuators (PCAs) are used to electrochemically control rubber biosynthetic rate and subsequent molecular weight in enzymatically active rubber particles purified from Ficus elastica (Indian rubber tree). RTase activity was assayed using ³H-FPP (initiator) and ¹⁴C-IPP (monomer). Since only one FPP molecular is needed to initiate a new rubber polymer, the ratio of incorporated ³H-FPP to ¹⁴C-IPP was used to calculate the mean molecular weight of newly synthesized polymers. PCAs exchange ions in solution through REDOX reactions which we show control cation concentration without dislodging the elongating rubber polymers from the RTase. PCAs demonstrated highly tunable control over monomer incorporation and molecular weight in both Mg²⁺ and Mn²⁺ cations. REDOX cycling PCAs did not irreversibly inhibit the rubber transferase complex, and no indication of enzymatic damage was observed. Precise PCA control of RTase activity may pave the way for rubber eventually to be produced in bioreactors. Full article

Between 2022 and 2024, a severe branch dieback disease was observed affecting over 6% of sweet cherry trees of the ‘Tieton’ cultivar in commercial greenhouses in southern Liaoning Province, China. Symptoms primarily occurred at the top of young branches. At the early stage of disease onset, the lesions appeared as dark brown, irregularly shaped areas with a moist surface; as the disease progressed, these lesions turned dry and rotten, leading to tree decline symptoms in sweet cherry trees. Disease diagnosis was carried out in sweet cherry greenhouses across Liaoning Province, where 24 diseased samples were collected and 14 fungal isolates were obtained therefrom. Based on morphological traits, cultural characteristics, and multi-locus phylogenetic analyses of the internal transcribed spacer (ITS) region, beta-tubulin (TUB2) gene, and translation elongation factor 1-α (TEF1) gene, these isolates were identified as Botryosphaeria dothidea. Two representative isolates, namely zdcy-1 and zdcy-2, were selected for pathogenicity assays. Both mycelial plug and spore suspension inoculation methods confirmed the pathogenicity of the pathogen. The biological characteristic assays revealed that the optimal temperature range for the pathogen’s mycelial growth on PDA medium was 25–28 °C, and the optimal pH range was 6.0–8.0. This study improves the understanding of branch dieback disease in sweet cherry orchards in China, enriches the knowledge regarding the geographical distribution, host range, and infection sites of the pathogen, and provides novel insights for the management of sweet cherry diseases. Full article

Through the mechanical analysis of AlCoCrFeNi thin-walled high-entropy alloy materials fabricated by plasma arc additive manufacturing, this study examines the practical application prospects of plasma arc manufacturing technology for thin-walled high-entropy alloys and explores its future development directions. Using a plasma arc oscillation process, a 50-layer fine additive experiment was conducted on AlCoCrFeNi high-entropy alloy materials employing both reciprocating and layer-by-layer accumulation methods. The samples were analyzed for overall appearance, microstructure, hardness, and tensile properties. The results indicate that the proportions of columnar and intergranular dendrites in the thin-walled high-entropy alloy specimens are similar, and the columnar dendrites exhibit a uniformly sized cross shape. The variation in Vickers microhardness along the horizontal direction shows lower strength at the edge positions, gradually increasing with horizontal distance. A comparison of the alloy’s transverse and longitudinal tensile specimens revealed that samples parallel to the deposition direction exhibit more regular structural arrangements, while specimens perpendicular to the deposition direction show unavoidable stress concentration at the deposition sites during tensile testing. With the increase in the height of the longitudinal specimens, the FCC structures in the alloy are significantly refined, the organizational arrangement becomes more regular, and the elongation increases. This study elucidates the plasma arc preparation technique for thin-walled high-entropy alloy materials, which is expected to achieve precise control over material composition, accurate observation of grain refinement, and uniform distribution of Vickers hardness, thereby enhancing the mechanical properties and thermal stability of the materials, with promising applications in aerospace, energy, and industrial fields. Full article

Quantitative real-time PCR (qPCR) remains a cornerstone method for analyzing gene expression due to its high sensitivity, specificity, and reproducibility. However, for reliable results in relative quantification studies, the choice of an appropriate reference gene is critical to ensure accurate normalization. The expression of commonly used reference genes can vary depending on developmental stage and experimental conditions, making their validation essential. To date, no validated reference genes have been reported for Agrostemma githago L. (corn cockle, Caryophyllaceae). To facilitate research on genes involved in natural product biosynthesis and specialized metabolism regulation, we aimed to identify the most stable reference genes across various plant organs and cultivation conditions of this species. Drawing on previous literature, we have selected seven housekeeping genes widely used for evaluation: actin, β-tubulin, elongation factor 1α, glyceraldehyde-3-phosphate dehydrogenase, histone H3, translation elongation factor 1, and eukaryotic translation initiation factor 5A1 (for which two primer sets were tested). The nucleotide sequences of these potential reference genes were identified from the A. githago transcriptome. Using qRT-PCR, transcript levels of seven potential reference genes were estimated in 40 different A. githago samples, including 25 in vitro samples under various treatment conditions and 15 soil-grown samples representing A. githago organs in different developmental stages. Expression stability of candidate reference genes was assessed using the RefFinder platform, which combines four commonly applied statistical algorithms: geNorm, NormFinder, BestKeeper, and the comparative Δ-Ct method. The results revealed that the selection of optimal reference genes varied based on the particular organ, developmental stage and condition being examined. TIF5A1-2 (one of the two primer pairs tested) and GAPHD consistently exhibited the most stable expression under various conditions in vitro. EF1α and H3 exhibited superior performance across different organs of soil-grown plants. Moreover, our integrated analysis enabled the identification of the two most stable, universal reference genes suitable for normalization in A. githago under all tested conditions—H3 and TIF5A1-2. Our work provides a robust foundation for future transcriptomic and functional studies of the specialized metabolism of A. githago and other related species. Full article

Accurate segmentation of marine oil spills in synthetic aperture radar (SAR) images is crucial for emergency response and environmental remediation. However, current deep learning methods are still limited by two long-standing bottlenecks: first, multiplicative speckle noise and complex background clutter make it difficult to accurately delineate actual oil spills; and second, limited receptive fields often lead to the geometric fragmentation of elongated, irregular oil films. To surmount these challenges, this paper proposes a novel framework termed the Frequency-Spatial Coordinate and Strip-Augmented Network (FCS-Net). First, we leverage the ConvNeXt-Small backbone to extract robust hierarchical features, utilizing its large kernel design to capture broad contextual information. Second, a Frequency-Spatial Coordinate Attention (FS-CA) module is proposed to integrate spatial coordinate encoding with global frequency-domain information. Third, to maintain the morphological integrity of elongated targets, we introduce a Strip-Augmented Pyramid Pooling (SAPP) module which employs anisotropic strip pooling to model long-range dependencies. Extensive experiments on the multi-source SOS dataset demonstrate the effectiveness of FCS-Net. The proposed method achieves state-of-the-art performance, reaching an mIoU of 87.78% in the Gulf of Mexico and 89.62% in the challenging Persian Gulf, outperforming strong baselines and demonstrating superior robustness in complex ocean scenarios. Full article

Epoxy resins often require toughening to broaden their engineering applications, such as in durable concrete repair. This study addresses this need by developing high-performance polyurethane/epoxy (PU/EP) interpenetrating polymer networks (IPNs). The composites were synthesized via prepolymer and stepwise methods using polyether polyol (PPG-1000), isocyanate (MDI-50), and E51 epoxy. At an optimal PU prepolymer content of 15 wt%, the polyether-based IPNs achieved a balanced mechanical profile (tensile strength: 59.90 MPa; elongation at break: 6.46%; compressive strength: 69.99 MPa). Further tuning of the soft segment by introducing polyester polyol (PS-2412) yielded superior performance at a PS-2412/PPG-1000 ratio of 30/70. This formulation increased tensile and compressive strengths by 11.4% and 6.07% (to 66.74 MPa and 74.24 MPa), and dry and wet bond strengths by 12.1% and 36.3% (to 5.68 MPa and 4.62 MPa), respectively. The enhancement is attributed to the increased crosslinking density and more uniform network structure imparted by PS-2412, which improves stress distribution and interfacial adhesion. This work provides an effective soft-segment design strategy for fabricating toughened epoxy composites with robust mechanical and adhesive properties. Full article

Objectives: Myopia of prematurity (MOP) is a refractive error occurring in individuals born prematurely and is considered a distinct entity from pathologic and school-age myopia. Children affected by MOP are at risk of developing high myopia, with an increased lifelong cumulative risk of related complications. The aim of this study was to evaluate the progression of MOP in children previously affected by retinopathy of prematurity (ROP) who wore spectacles with Highly Aspherical Lenslet Target (HALT) technology compared to conventional single-vision lenses during childhood. Methods: Enrolled subjects were divided into two groups: subjects who used HALT lenses for at least 12 months and children who used standard single-vision lenses for the same period. The temporal evolution of spherical equivalent (SE) and axial length (AL) was evaluated in both groups. Results: Of the 252 preterm children screened, 58 were included in the study: 38 subjects (66%) in the standard lenses group and 20 subjects (34%) in the HALT lenses group. At 12 months SE progression and AL elongation in the HALT group (−0.32 ± 0.20 D and 0.12 ± 0.05 mm) were lower compared to the standard group (−0.93 ± 0.34 D and 0.46 ± 0.09 mm, p < 0.0001). Conclusions: The progression of MOP appears to be reduced in subjects corrected with HALT lenses compared to those wearing conventional lenses. These results suggest further investigation of HALT technology in selected subgroups of patients at high-risk of severe myopia to reduce its progression and the related lifelong cumulative risk of visual impairment. Full article

This study presents an analytical methodology for evaluating the influence of hull design parameters on the controllability and manoeuvrability of ships equipped with integrated electric propulsion systems. Unlike traditional approaches that examine the hull and propulsion plant independently, the proposed method employs a generalized model of transient modes within the propulsion complex, enabling the coupled interaction among the hull, propulsion units, electric motors, and the electrical power system to be captured during manoeuvring. Active experimental design and regression modelling are applied to construct controllability diagrams, identify the most influential dimensionless parameters, and reduce computational effort. The methodology is used to assess the effect of hull elongation (0.08–0.16 L) with curvature variation limited to 6%. The results show that this degree of elongation has minimal impact on turning performance and course-keeping stability, confirming the feasibility of such design modifications. The proposed approach provides an effective tool for early-stage design and modernization of electric ships and supports decision-making in ship behaviour prediction and traffic management. Full article

In this study, hydroxyapatite was synthesized using a microwave-assisted hydrothermal method. Calcium nitrate tetrahydrate (Ca(NO₃)₂·4H₂O) and ammonium phosphate ((NH₄)₂HPO₄) served as precursors in a pH 10 ammonium hydroxide (NH₄OH) solution. Polyvinylpyrrolidone (PVP) was employed as a surfactant at varying concentrations of 0 (M0), 0.1% (M1), 0.2% (M2), and 0.3%wt (M3) to control particle size and morphology. The synthesized samples were characterized using Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The addition of PVP during synthesis resulted in Ca/P ratios ranging from 0.93 to 1.37, and promoted predominantly rod-like morphologies. Samples M1 and M3 exhibited average diameters of 11.23–104.24 nm and lengths of 47.21–222.32 nm. XRD analysis confirmed the presence of both hexagonal and monoclinic phases, with crystallite sizes varying from 18.66 to 22.49 nm. FTIR spectra of sample M1 revealed an elongation at 3432 cm⁻¹ corresponding to OH⁻ groups, indicative of water absorption within the material structure. Vibrational bands at 2950–2300, 1090, and 975 cm⁻¹, attributed to C–H bonds in PVP were also identified. These findings highlight the influence of PVP concentration on the structural and morphological properties of hydroxyapatite, providing insights into its potential applications in various fields. Full article

Amid the intensifying global mandate for sustainable aquafeed strategies, this study investigates the functional efficacy and biochemical implications of black soldier fly larvae oil (BLO), extracted via recently approved patent method depending on cold-aqueous process, as a substitute for conventional fish oil (FO) in zebrafish (Danio rerio) diets. The refined extraction technique, representing an advancement over traditional aqueous methodologies, was engineered to selectively preserve bioactive lipid fractions while minimizing environmental footprint and processing residues. Over a 28-day feeding period, adult zebrafish were allocated into triplicate groups and fed diets comprising 0%, 50%, and 100% substitution of FO with BLO and growth, lipid composition, and dietary fatty acid profiles of both diets and flesh were rigorously evaluated. Zebrafish fed the BLO₁₀₀ diet exhibited the most pronounced somatic growth (2.47 ± 0.01 g), significantly elevated specific growth rates (3.88 ± 0.82% day⁻¹), and the most efficient feed conversion, without compromising survival. Flesh lipid analysis revealed a substantial enrichment in saturated fatty acids—most notably lauric acid (C12:0)—corresponding to increasing dietary BLO levels. Although dietary EPA and DHA levels were reduced, DHA concentrations in fish tissues remained comparable to those of the control group, indicating a compensatory capacity mediated by endogenous elongation and desaturation pathways. These findings substantiate the dual potential of BLO as both a nutritionally viable lipid source and a vector for enhancing aquafeed sustainability. The cold-aqueous extraction method demonstrated here underscores a pivotal advancement in green lipid processing, aligning oil quality with ecological stewardship. This integrative approach not only reinforces BLO’s candidacy as a strategic fish oil substitute but also delineates a pathway toward scalable, species-adapted feed innovation. Future investigations should prioritize the modulation of fatty acid profiles through dietary and extraction optimization to fully realize the translational potential of insect-derived lipids in aquaculture. Full article

Various methods for classifying and evaluating the shape, size, and surface texture of sand particles are examined, highlighting their impact on concrete mixture properties. This study emphasizes the role of particle morphology in determining concrete workability and segregation, particularly in glass-fiber-reinforced (GRC) thin-layer concrete for building facade panels. The effects of different aggregate types on concrete workability and segregation are analyzed, showing that aggregates with spherical particles and a lower elongation index improve mixture consistency and reduce segregation. Three types of fine aggregates were used (instead of quartz sand in the mixtures, natural sand and granite screenings were chosen, which would be a sustainable alternative to quartz sand), and thin-layer glass-fiber-reinforced concrete using aggregates of different shapes was characterized by layering the mixture. The workability and segregation of fine-grained fiberglass-reinforced concrete mixtures depend on the aggregate particles’ shape. Up to 50% of quartz sand can be replaced with granite siftings or natural sand, as measured by the segregation index, as calculated according to the method proposed in this paper. Increasing the amount of natural sand from 10% to 50% also increases the segregation index from 1.9 to 2.6, and when using granite sifting aggregates, it rises from 2.6 to 3.5. Aggregates with spherical particles are more suitable for this thin-layer GRC concrete, if we examine the consistency parameters of fresh concrete and the possibilities of working with it in real production conditions. Full article

Nickel–Aluminum–Bronze (NAB) has gained significant attention in marine applications due to its excellent corrosion resistance and has shown growing potential for laser powder bed fusion (L-PBF) additive manufacturing. However, research on the fabrication of NAB alloys using L-PBF remains relatively limited. In this study, fully dense NAB samples were successfully fabricated through L-PBF process parameter optimization. The microstructural evolution and mechanical properties of both as-built and annealed L-PBF samples were systematically investigated and compared with those of traditionally cast NAB. The results reveal that the as-built L-PBF specimens primarily consist of columnar β′ grains, with the α phase distributed along the grain boundaries and a small amount of κ phase precipitated within the β′ matrix, distinctly different from the cast microstructure characterized by a columnar α-phase matrix with precipitated β′ and κ phases. After annealing at 675 °C for 6 h, the β′ phase in both methods decomposed into α + κ phases, and the original columnar structure in the L-PBF specimens transformed into a dendritic morphology. Compared to the cast samples, the L-PBF-produced NAB alloy exhibited significantly enhanced yield strength, tensile strength, and microhardness, attributable to rapid solidification during the L-PBF process. Following annealing, the yield strength and elongation increased by 12.8% and 184.4%, respectively, compared to the as-built condition, resulting from the decomposition of the martensitic phase into α + κ phases and further grain refinement. Full article

Titanium alloys and copper have broad applications in aerospace, defense, and industry, but their dissimilar welding faces challenges from significant physicochemical differences and easy formation of brittle Ti-Cu intermetallic compounds, while existing methods like laser welding or friction stir welding have limitations, such as low strength or inability to weld ultra-thin plates. This study adopted cold welding to join Ti-6.5Al-1Mo-1V-2Zr alloy and 99.90% pure copper. The mechanical properties of the joint were tested, the microstructure and fracture of the weld were observed, and the phase composition of the weld was analyzed. The results show that the weld fusion zone mainly consists of Cu-based solid solution and Cu₃Ti. Low cold welding heat input reduces the Cu₃Ti content, so the joint mechanical properties do not decrease significantly. The tensile strength of the joint reaches 284 MPa, which is 83% of that of copper-based metals, and the elongation rate reaches 6.25%. Diffusion kinetics and solidification thermodynamics analyses confirm that Cu₃Ti intermetallic compounds are preferentially generated in the weld seam. Full article

Fusarium head blight (FHB), caused mainly by the Fusarium graminearum species complex, is a devastating cereal disease associated with yield losses and mycotoxin contamination. Early infection is closely linked to spore germination and germ tube elongation, yet conventional monitoring methods are labor-intensive and poorly suited for dynamic phenotypic quantification. We present EffiFormer-CGS, a three-module deep learning framework integrating object detection, key point localization, and phenotypic quantification for microscopic images of FHB spores. A dataset of 2381 images was generated from systematic experiments with triazole fungicides (Prochloraz, Prothioconazole, and Tebuconazole) across multiple concentrations and time points. Spores were annotated with bounding boxes and fine-grained geometric key points, enabling calculation of germination degree as the ratio of germ tube length to body length. EffiFormer-CGS achieved 90.8% mAP@0.5:0.95 in object detection and 91.4% mAP@0.5 in key point localization. All fungicides significantly inhibited germination, with Prochloraz showing the strongest effect. Predictions closely matched manual counts, with germination rate errors ≤ 5.18%. EffiFormer-CGS provides an efficient, automated, and high-precision approach for spore germination analysis, supporting high-throughput fungicide screening, resistance monitoring, and sustainable FHB management. Full article

Populus euphratica is a key constructive species in desert ecosystems and plays a vital role in maintaining their stability. However, effective automated methods for accurately delineating its distribution outlines are currently lacking. This study used the mainstream area of the Tarim River as a case study and proposed a technical solution for identifying the distribution outline of Populus euphratica using multi-source thematic classification data. First, cropland thematic data were used to optimize the accuracy of the Populus euphratica classification raster data. Discrete points were removed based on density to reduce their impact on boundary identification. Then, a hierarchical identification scheme was constructed using the alpha-shape algorithm to identify the boundaries of high- and low-density Populus euphratica distribution areas separately. Finally, the outlines of the Populus euphratica distribution polygons were smoothed, and the final distribution outline data were obtained after spatial merging. The results showed the following: (1) Applying a closing operation to the cropland thematic classification data to obtain the distribution range of shelterbelts effectively eliminated misclassified pixels. Using the kd-tree algorithm to remove sparse discrete points based on density, with a removal ratio of 5%, helped suppress the interference of outlier point sets on the Populus euphratica outline identification. (2) Constructing a hierarchical identification scheme based on differences in Populus euphratica density is critical for accurately delineating its distribution contours. Using the alpha-shape algorithm with parameters set to α = 0.02 and α = 0.006, the reconstructed geometries effectively covered both densely and sparsely distributed Populus euphratica areas. (3) In the morphological processing stage, a combination of three methods—Gaussian filtering, equidistant expansion, and gap filling—effectively ensured the accuracy of the Populus euphratica outline. Among the various smoothing algorithms, Gaussian filtering yielded the best results. The equidistant expansion method reduced the impact of elongated cavities, thereby contributing to boundary accuracy. This study enhances the automation of Populus euphratica vector data mapping and holds significant value for the scientific management and research of desert vegetation. Full article