Search Results (3,125)

Structural variation (SV) serves as a fundamental driver of phenotypic diversity and environmental adaptation in plants and animals, significantly influencing key agronomic traits in crops. Common wheat (Triticum aestivum L.), an allohexaploid species, harbors extensive chromosomal SVs and distant hybridization-induced recombination events that provide critical resources for genetic improvement. This study utilizes non-denaturing fluorescence in situ hybridization (ND-FISH) and oligonucleotide multiplex probe-based FISH (ONPM-FISH) to analyze the karyotypes of 153 BC₁F₄–BC₁F₆ lines derived from the hybrid line Xiaoyan 7430 and common wheat Yannong 1212. The results revealed that Xiaoyan 7430 carries 8 alien chromosome pairs and 20 wheat chromosome pairs (lacking 6B), and Yannong 1212 contains 21 pairs of wheat chromosomes. The parental lines exhibited presence/absence variations (PAVs) on chromosomes 2A, 6A, 5B, 1D, and 2D. Chromosomal variations, including numerical chromosomal variation (NCV), structural chromosomal variation (SCV), and complex chromosomal variation (CCV), were detected in the progeny lines through ONPM-FISH analysis. The tracking of alien chromosomes over three consecutive generations revealed a significant decrease in transmission frequency, declining from 61.82% in BC₁F₄ to 26.83% in BC₁F₆. Telosomes were also lost during transmission, declining from 21.82% in BC₁F₄ to 9.76% in BC₁F₆. Alien chromosome 1J^S, 4J, and 6J exhibited the highest transmission stability and were detected across all three generations. Association analysis showed that YN-PAV.2A significantly affected the length/width ratio (LWR) and grain diameter (GD); YN-PAV.6A, XY-PAV.6A, and PAV.5B increased six grain traits (+2.25%~15.36%); YN-PAV.1D negatively affected grain length (GL) and grain circumference (GC); and XY-PAV.2D exerted positive effects on thousand-grain weight (TGW). Alien chromosomes differentially modulated grain characteristics: 1J^S and 6J both reduced grain length and grain circumference; 1J^S increased LWR; and 4J negatively impacted TGW, grain width (GW), GD, and grain area (GA). Meanwhile, increasing alien chromosome numbers correlated with progressively stronger negative effects on grain traits. These findings elucidate the genetic mechanisms underlying wheat chromosomal variations induced by distant hybridization and their impact on wheat grain traits, and provide critical intermediate materials for genome design breeding and marker-assisted selection in wheat improvement. Full article

Gradient structure provides an effective approach to improve the combination of high strength and toughness compared to a uniform one. The gradient interfaces or boundaries in gradient-structured metallic glass composites play a crucial role in influencing mechanical properties. Our findings indicate the gradient microstructure significantly induces temporal and spatial stress localization, which can modulate the generation and propagation of shear bands. The synergistic gradient effects generated by heterogeneous grain sizes and interface characteristics can enhance both the strength (yield stress and peak stress) and the toughness of gradient network-structured metallic glass composites as the grain size gradient and the boundary width increase. Our work demonstrates the appropriate gradient of grain size, and the boundary structure should potentially lead to enhanced work hardening. Full article

In order to solve the problem encountered by traditional potato–stem separation devices, that is, they cannot meet the requirements when installed in small-scale harvesters, a new type of vertical differential roller potato–stem separation device was developed. The device features a compact structure and simultaneously possesses both separating and conveying functions. Through the analysis of the separation force between potato and stem, the structure and parameters of the separation device were determined. The simulation and the field test of the potato–stem separation process were carried out with the vertical differential roller speed, the vertical differential roller gap width and the conveyor chain speed as the influencing factors. The simulation test analysed the influence law of different working parameters on the performance of potato–stem separation. The field test revealed the order of the effects of various factors on the impurity rate and skin-breaking rate, concluding that the optimal combination of operational parameters was a vertical differential roller rotational speed of 6 s⁻¹, a vertical differential roller gap width of 7 mm, and a conveyor chain speed of 1.4 m·s⁻¹. This experiment fills the research gap in the study of potato–stem separation devices suitable for small-scale potato harvesters and promotes the development of compact potato harvesters. Full article

Melon has great economic importance in Brazil, and flower development is the basis for fruit and seed production. The objective of this study was to elucidate the variability of flowering characteristics and to compare qualitative and quantitative reproductive variations in relation to pollen viability and stigmatic receptivity in 21 genotypes, which includes 15 Brazilian accessions. In addition, we evaluated the influence of time on the growth of the pollen tube and its arrival at the ovule in vivo at different intervals (1 h, 2 h, 3 h) after hand pollination in three commercial varieties, one exotic accession, and two intervarietal hybrids, by epifluorescence technique. Three groups were distributed by the clustering method of Scott–Knott at 5% probability; group III included only commercial varieties for the flower width descriptor. C. melo germplasm presented 81% andromonoecious plants and 19% trimonoecious plants. Through the multivariate strategy, these 21 genotypes were distributed into six groups with distinct reproductive characteristics, and male flowering was accelerated compared to female flowering. Regarding pollen viability, it was greater than 95% according to staining methods. Pollen germination rate in vivo was affected by time, with an almost 12.5% increase between 1 h and 3 h after hand pollination, and the in vivo pollen germination in hybrids was lower than in commercial varieties. Brazilian accessions, despite stability in pollen viability and stigma receptivity, have great differences in reproductive terms, such as variations in the quantitative and qualitative characteristics of floral pieces and flowering. This work contributes to the knowledge on varieties, hybrids, exotic accession, and Brazilian melon germplasm by characterizing some of their main agricultural traits, such as reproduction floral biology, and opens up prospects for yield evaluation in plant breeding programs. Full article

Pulsatile blood flow generates complex wall shear stress (WSS) patterns at the carotid bifurcation, which critically regulate endothelial function and structure. While physiological pulsatile WSS (PWSS) is essential for maintaining vascular health, low oscillatory WSS (OWSS) near the carotid sinus is closely associated with endothelial dysfunction, atherosclerotic plaque formation, and stenosis. Reproducing these hemodynamic conditions in vitro is therefore crucial for investigating endothelial mechanobiology and elucidating the pathogenesis of atherosclerosis. Although microfluidic technologies have emerged as promising platforms for simulating either pulsatile or oscillatory WSS, a system capable of simultaneously replicating both characteristic waveforms—as found in vivo at the carotid bifurcation—remains undeveloped. In this study, we designed a variable cross-section microfluidic channel using Computational Fluid Dynamics (CFD) simulations. Numerical results demonstrate that the optimized channel accurately reproduces low OWSS at a stepped section emulating the carotid sinus, alongside high PWSS in a downstream uniform section. Vortex formation induced by the step structure is identified as key to generating low OWSS, influenced by step height, channel width ratio, and input flow rate. This work provides a novel and robust methodology for designing microfluidic systems that mimic complex hemodynamic microenvironments, facilitating future studies on the interplay between distinct WSS patterns and endothelial dysfunction. Full article

To investigate hydraulic fracture propagation in multi-layered porous media such as sand–coal interbedded formations, we present a new phase-field-based model. In this formulation, a diffuse fracture is activated only when the local element strain exceeds the rock’s critical strain, and the fracture width is represented by orthogonal components in the x and y directions. Unlike common PFM approaches that map the permeability directly from the damage field, our scheme triggers fractures only beyond a critical strain. It then builds anisotropy via a width-to-element-size weighting with parallel mixing along and series mixing across the fracture. At the element scale, the permeability is constructed as a weighted sum of the initial rock permeability and the fracture permeability, with the weighting coefficients defined as functions of the local width and the element size. Using this model, we examined how the in situ stress contrast, interface strength, Young’s modulus, Poisson’s ratio, and injection rate influence the hydraulic fracture growth in sand–coal interbedded formations. The results indicate that a larger stress contrast, stronger interfaces, a greater stiffness, and higher injection rates increase the likelihood that a hydraulic fracture will cross the interface and penetrate the barrier layer. When propagation is constrained to the interface, the width within the interface segment is markedly smaller than that within the coal-seam segment, and interface-guided growth elevates the fluid pressure inside the fracture. Full article

Given the high casualty rate on expressways, this study aimed to accurately predict traffic accident rates and the key factors influencing them. Taking an expressway in Southern China as the research object, we constructed a two-layer stacking model integrating neural networks and tree models, based on accident data, traffic flow data, and road segment characteristic data. Six base models were integrated for prediction, and the Shapley Additive exPlanations (SHAP) method was used to analyze influencing factors. Results showed that the proposed model achieved the best performance, with a root mean square error (RMSE) of 11.05 and a mean absolute error (MAE) of 6.12, and its performance was significantly superior to that of other models (p < 0.05). Results from hyperparameter optimization and 5-fold cross-validation indicated that the proposed model had an RMSE of 8.91 ± 2.03, which was better than that of other models. Among all input factors, the proportion of tunnel length to total length and the variance of bridge width had the most significant impact on the expressway traffic accident rate, while the average width of tunnels had the lowest impact. This study realizes accurate prediction using widely available data and clarifies key factor mechanisms, providing support for expressway safety management and early risk warnings. Full article

Glacial lake outburst floods (GLOFs) represent increasingly common and high-magnitude geohazards across the cryosphere of the Tibetan Plateau, particularly under ongoing climate warming and glacier retreat. This study combines multi-temporal remote sensing imagery and detailed Flo-2D hydrodynamic modeling to investigate the erosive dynamics of the 2020 Jinwuco GLOF in Southeastern Tibetan Plateau. Key conclusions include: (1) The 2.35 km-long flood routing channel exhibits pronounced non-uniformity in horizontal curvature, channel width, and cross-sectional shape, significantly influencing flood propagation; five representative cross-sections divide the channel into six distinct segments. (2) Prominent lateral erosion occurred proximally to the dam, attributable to extreme erosive forces and high sediment transport capacity during peak discharge, with horizontal channel curvature further amplifying local impact and erosion. (3) Erosion rates were highest near the dam and in downstream narrow segments, while mid-reach sections with greater width experienced lower erosion. (4) Maximum flow depths reached 28.12 m in topographically confined reaches, whereas peak velocities occurred in upstream and downstream curved sections. (5) The apparent critical erosive shear stress of bank material is controlled not only by soil strength but also by flood dynamics and pre-existing channel morphology, indicating strong feedback between flow dynamics, channel morphology, and critical erosive shear stress of bank material. This study provides a generalized and transferable framework for analyzing GLOF-related erosion in data-scarce high-altitude regions, offering critical insights for hazard assessment, regional planning, and risk mitigation strategies. Full article

Background: The posterosuperior maxillary region poses a challenge in orthognathic surgery due to its complex three-dimensional anatomy. The pterygomaxillary suture (PMS) is a key landmark for various procedures. Understanding its anatomical relationships is essential to improving surgical precision. Methods: A retrospective analysis of CBCT images from 120 patients aged 18–70 years at Ankara Medipol University was conducted. Patients were categorized into skeletal Classes I, II, and III according to the ANB angle. Linear and angular measurements of the PMS and adjacent structures were performed. The statistical analysis included the Shapiro–Wilk, Independent t-test, Mann–Whitney U test, and regression analysis (p < 0.05). Results: There were clear differences between the skeletal groups. Class II and III patients had a lesser lateral PMS–baseline intersection distance (IV–VI) and Class II had a lesser medial PMS–baseline perpendicular distance (VV′) compared to Class I (p < 0.05). Additionally, the angle V–IV–VI was significantly narrower in Class II and III groups, indicating altered PMS orientation in these skeletal patterns. Conclusions: PMS morphology, including thickness, width, and angulation, is influenced by skeletal pattern. A preoperative CBCT assessment and individualized surgical planning are essential to ensure the safety and accuracy of Le Fort I osteotomies, especially in Class II and III patients. Full article

This paper presents the results of preliminary numerical and experimental studies concerning the sealing performance of static seals (gaskets) with geometrically designed sealing surface microstructures. The concept of the microstructure, inspired by the operating principle of Tesla’s one-way valve, relies on the generation of localized flow circulation within the microchannels formed between the contact surfaces, which increases flow resistance and reduces leakage. CFD simulations were performed to assess the influence of the geometric parameters of the microstructure on the leakage rate. The numerical calculations demonstrated that introducing microstructures into the gap formed between the contact interfaces can significantly reduce leakage, with the most critical geometric parameters being the gap width between the microprotrusions, their packing density, and their height. Experimental studies confirmed the higher sealing performance of structured gaskets compared to quasi-smooth gaskets, particularly at lower contact pressures. An analysis of the effective contact surface revealed that the improvement in tightness is a result of both the local intensification of the contact pressure and the flow effects induced by the microprotrusions. The results obtained confirm that an appropriately designed surface microstructure can substantially enhance the sealing performance of flange-bolted joints, even under relatively low clamping loads. Full article

The post-fracture mechanical performance of laminated glass (LG) members is well-known to be challenging to assess due to the influence of multiple factors. Even more challenging and scarcely explored is the assessment of the behavior of broken LG elements as a function of the degree of damage that affects it. In this paper, the attention is given to the experimental analysis of 2-ply, small-scale, pre-fractured LG elements composed of annealed (AN) glass and characterized by two different types of interlayers, namely the polymeric Ethylene-Vinyl Acetate (EVA) or the ionoplast SentryGlas^® (SG) bonds. The samples—with total size of 200 mm in length by 50 mm in width—are subjected to n = 10 repeated hard-body impact tests, in a three-point-bending (3PB) setup, to simulate and assess a possible increase in the damage severity. To quantify and compare the behavior of the different interlayers in use, experimental modal analyses are performed both at the beginning of the impact tests (n = 0) and after each hard-body impact repetition (n = 1, …, 10), by means of roving hammer tests based on #14 different control points. The comparison of the experimental outcomes—in particular, the fundamental vibration frequency f₁—gives evidence of a markedly different mechanical response from the EVA and SG interlayers. EVA samples exhibited a major reduction in terms of fundamental frequency, indicating significant propagation of damage following impact repetitions. On the other hand, SG samples appear to be less seriously affected by hard-body impacts. Full article

Accurate load forecasting for community-level heating, ventilation, and air conditioning (HVAC) plays an important role in determining an efficient strategy for demand response (DR) and the operation of the power grid. However, community-level HVAC includes various building-level HVACs, whose usage patterns and standard parameters vary, causing the challenge of load forecasting. To this end, a novel deep learning model, multiscale and cross-variable transformer (MSCVFormer), is proposed to achieve accurate community-level HVAC probabilistic load forecasting by capturing the various influences of multivariables on the load pattern, providing effective information for the grid operators to develop DR and operation strategies. This approach is combined with the multiscale attention (MSA) and cross-variable attention (CVA) mechanism, capturing the complex temporal patterns of the aggregated load. Specifically, by embedding the time series decomposition into the self-attention mechanism, MSA enables the model to capture the critical features of time series while considering the correlation between multiscale time series. Then, CVA calculates the correlations between the exogenous variable and aggregated load, explicitly utilizing the exogenous variables to enhance the model’s understanding of the temporal pattern. This differs from the usual methods, which do not fully consider the relationship between the exogenous variable and aggregated load. To test the effectiveness of the proposed method, two datasets from Germany and China are used to conduct the experiment. Compared to the benchmarks, the proposed method achieves outperforming probabilistic load forecasting results, where the prediction interval coverage probability (PICP) deviation with the nominal coverage and prediction interval normalized averaged width (PINAW) are reduced by 46.7% and 5.25%, respectively. Full article

The fabrication of microfluidic components using low-cost Fused Deposition Modeling (FDM) presents an attractive alternative to conventional manufacturing methods, yet achieving microscale dimensional accuracy remains a significant challenge. This study investigates the influence of five key FDM parameters (nozzle temperature, bed temperature, printing speed, flow rate, and infill overlap) on the dimensional accuracy of microchannels printed with PETG and TPU filaments. A Taguchi L27 orthogonal array was employed to systematically evaluate the effects of these parameters on width and depth deviations across sub-millimeter microchannel geometries. Results show that for PETG, optimal dimensional fidelity was achieved at 240 °C nozzle temperature, 70 °C bed temperature, 30 mm/s speed, 100% flow rate, and 15% overlap, enabling reliable channel widths down to 100 µm. TPU exhibited greater variability due to its elasticity, with optimal settings found at 220 °C, 60 °C bed temperature, 30 mm/s, 100% flow rate, and 25% overlap. Signal-to-noise ratio and ANOVA analyses revealed flow rate and printing speed as dominant factors for both materials. The findings provide a reproducible optimization framework for microscale FDM fabrication and highlight material-specific process sensitivities critical to functional microfluidic device performance. Full article

This paper focuses on the scoring-wheel cutting process for circular structures of OLED display panels, conducting in-depth research through an experiment–analysis–optimization system. Based on the Taguchi experimental design, a three-factor, five-level experiment is conducted, with the blade wheel angle (A), cutting speed (B), and pressure (C) set as influencing factors, and the scratch depth (h), width (w), median crack depth (l), and transverse crack width (d) set as evaluation indicators. The experiments are carried out using a self-developed dicing-wheel cutting device, and the morphology, roughness, and hardness of the cutting surface and cross-section are characterized by means of ultra-depth-of-field microscopy, laser confocal microscopy, microhardness tester, and other equipment. The research shows that the order of factors affecting the cutting quality is as follows: A > C > B. Through the analysis of morphology and crack characteristics, it is determined that the optimal parameter combination is a dicing wheel angle of 130°, a cutting speed of 20 mm/s, and a pressure of 11 N. The verification results indicate that this combination can reduce surface roughness, stabilize hardness, and realize efficient and precise processing of special-shaped structures in OLED display panels, providing strong theoretical and technical support for industrial process optimization. Full article

Droplet-based microfluidics has rapidly advanced applications in chemistry, biology, materials science, medicine, food science, and cosmetics. Using this technology, various oils have been employed for fluid encapsulation. This study is the first to investigate the use of an animal-based unsaturated fatty acid oil—emu oil—for microdroplet formation. We characterized droplet generation in the presence and absence of a non-fluorinated surfactant at a defined concentration and examined the influence of geometrical parameters using T-junction microchannels with two different central channel widths. The results were compared with those obtained from a plant-based oil (olive oil) under parallel experimental conditions. Given the growing concerns regarding the environmental and health risks of fluorocarbon oils combined with fluorinated surfactants, which are widely used in microfluidics, emu oil represents a potentially safer alternative for microdroplet-based technologies across multiple fields. Full article