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The dorsal root ganglion T-junction:a critical node in somatosensory processing and pain pathogenesis 被引量:1
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作者 ZHANG Zhi-He FU Yun-Jie WANG Yun 《生理学报》 北大核心 2026年第1期5-15,共11页
Pseudounipolar neurons in the dorsal root ganglia(DRG),as the central nodes of primary sensory afferents,possess a distinctive T-junction that is not merely a morphological peculiarity but also performs complex roles ... Pseudounipolar neurons in the dorsal root ganglia(DRG),as the central nodes of primary sensory afferents,possess a distinctive T-junction that is not merely a morphological peculiarity but also performs complex roles in rapid,multiplexed shunting and regulation of sensory signals.This specialized geometry enables separation,filtering,and feedback regulation of neuronal signals,thereby coordinating peripheral and central responses at multiple levels.Recent advances,including spatial transcriptomics,single-cell sequencing,super-resolution microscopy,organoid models,and novel electrophysiological methods,have permitted more precise dissection of the T-junction's molecular composition,ion-channel distribution,and electrophysiological properties.Here,we review current knowledge of the T-junction's developmental regulation and multilayered molecular networks,and we detail its functional alterations in both physiological signaling and pathological pain states,with particular emphasis on ion-channel modulation,signal attenuation,and selective transmission mechanisms.Finally,we discuss contemporary pain-intervention approaches and prospects for precision-targeted therapies,aiming to provide a theoretical foundation for future studies in pain physiology and clinical translation. 展开更多
关键词 dorsal root ganglia pseudounipolar neuron T-JUNCTION sensory signaling PAIN
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体外环境下C-Root BP材料根尖封闭性及抗力强度
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作者 周丽静 王双 +2 位作者 向谨姣 王会超 柴雪姣 《中国组织工程研究》 北大核心 2026年第26期6868-6872,共5页
背景:近年来,生物陶瓷材料因具有良好的生物相容性和封闭性能逐渐成为根尖倒充填的首选材料,其中生物陶瓷材料C-Root BP、iRoot BP Plus均具有良好的生物相容性和封闭性能。目的:对比体外环境下C-Root BP与iRoot BP Plus材料的根尖封闭... 背景:近年来,生物陶瓷材料因具有良好的生物相容性和封闭性能逐渐成为根尖倒充填的首选材料,其中生物陶瓷材料C-Root BP、iRoot BP Plus均具有良好的生物相容性和封闭性能。目的:对比体外环境下C-Root BP与iRoot BP Plus材料的根尖封闭性能及抗力强度。方法:于2022年6月至2024年6月期间,收集石家庄市第二医院口腔科因正畸或牙周病新鲜拔除的单根离体牙56颗,随机分4组处理:iRoot BP Plus组(n=16)、C-Root BP组(n=16)根管预备和消毒后分别采用iRoot BP Plus、C-Root BP材料进行根尖倒充填,阳性对照组(n=16)根管预备和消毒后使用蒸馏水进行根尖倒充填,阴性对照组(n=8)仅行根管预备和消毒(不进行根尖倒充填处理),采用染料渗透法检测根尖封闭性;制作根管细菌渗漏体外模型,评价细菌微渗漏发生情况;采用薄片推出实验检测填充材料与牙本质之间的粘连强度,并在显微镜下观察断裂形式。结果与结论:(1)染料染色7 d后,阳性对照组染料渗透长度大于iRoot BP Plus组、C-Root BP组(P<0.05),iRoot BP Plus组和C-Root BP组染料渗透长度比较差异无显著性意义(P>0.05);(2)经过90 d培养,阳性对照组细菌微渗漏发生率高于iRoot BP Plus组、C-Root BP组(P<0.05),iRoot BPPlus组和C-Root BP组细菌微渗漏发生率比较差异无显著性意义(P>0.05);(3)C-Root BP组填充材料与牙本质之间的粘连强度大于iRootBP Plus组(P<0.05),两组断裂面断裂形式比较差异无显著性意义(P>0.05);(4)结果表明,采用C-Root BP和iRoot BP Plus材料进行根尖倒充填可产生相似的根尖封闭效果,并且断裂形式也基本一致,但C-Root BP材料具有良好的粘连强度。 展开更多
关键词 C-root BP iroot BP Plus 根尖倒充填 根尖封闭性 抗力强度 细菌 根管治疗 生物材料
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Process fault root cause diagnosis through state evolution mapping based on temporal unit shapelets
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作者 Zhenhua Yu Guan Wang +1 位作者 Qingchao Jiang Xuefeng Yan 《Chinese Journal of Chemical Engineering》 2025年第8期96-106,共11页
Accurate fault root cause diagnosis is essential for ensuring stable industrial production. Traditional methods, which typically rely on the entire time series and overlook critical local features, can lead to biased ... Accurate fault root cause diagnosis is essential for ensuring stable industrial production. Traditional methods, which typically rely on the entire time series and overlook critical local features, can lead to biased inferences about causal relationships, thus hindering the accurate identification of root cause variables. This study proposed a shapelet-based state evolution graph for fault root cause diagnosis (SEG-RCD), which enables causal inference through the analysis of the important local features. First, the regularized autoencoder and fault contribution plot are used to identify the fault onset time and candidate root cause variables, respectively. Then, the most representative shapelets were extracted to construct a state evolution graph. Finally, the propagation path was extracted based on fault unit shapelets to pinpoint the fault root cause variable. The SEG-RCD can reduce the interference of noncausal information, enhancing the accuracy and interpretability of fault root cause diagnosis. The superiority of the proposed SEG-RCD was verified through experiments on a simulated penicillin fermentation process and an actual one. 展开更多
关键词 root cause diagnosis Neural networks shapelet FERMENTATION BIOPROCESS
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Sensing the dry:Redox-regulated auxin repression shapes root plasticity
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作者 Ali Shahzad Hameed Gul 《Advanced Agrochem》 2025年第4期313-315,共3页
Root architecture is crucial for plant survival under drought,yet how water stress signals shape root development has remained unclear.Recently,Roy et al.(Science)revealed that drought-induced accumulation of reactive... Root architecture is crucial for plant survival under drought,yet how water stress signals shape root development has remained unclear.Recently,Roy et al.(Science)revealed that drought-induced accumulation of reactive oxygen species(ROS)in root nuclei triggers the auxin repressor IAA3 to form complexes(multimerization)that enable the recruitment of the co-repressor TOPLESS(TPL),thereby suppressing auxin signaling and blocking lateral root initiation.ROS signaling acts rapidly,within minutes of water deprivation,compared to slower ABA responses,allowing plants to quickly adjust lateral root growth.This discovery reveals a new redoxhormone regulatory mechanism that enables plants to fine-tune root branching during transient drought.Beyond advancing our understanding of adaptive root responses,these insights highlight potential molecular targets for developing crops with improved resilience under water limitation. 展开更多
关键词 Transient drought Redox regulation root adaptation
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Synchronized capture of 3D shape and color texture based on phase-shifting profilometry
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作者 WANG Su-zhen WU Wei +2 位作者 JI Yi-xin ZHANG Long-xiang WANG Jian-hua 《中国光学(中英文)》 北大核心 2026年第1期228-238,共11页
In recent years,the demand for synchronous acquisition of three-dimensional(3D)shape and col-or texture has surged in fields such as cultural heritage preservation and healthcare.Addressing this need,this paper propos... In recent years,the demand for synchronous acquisition of three-dimensional(3D)shape and col-or texture has surged in fields such as cultural heritage preservation and healthcare.Addressing this need,this paper proposes a novel method for simultaneous 3D shape and color texture capture.First,a linear model correlating camera exposure time with grayscale values is established.Through exposure time calibration,the projected red,green and blue(RGB)light and white-light grayscale values captured by a monochrome cam-era are aligned.Then,three sets of color fringes are projected onto the object to identify optimal pixels for 3D reconstruction.And,three pure-color patterns are projected to synthesize the color texture.Experimental res-ults show that this method effectively achieves synchronous 3D shape and color texture acquisition,offering high speed and precision,and avoids color crosstalk interference common in 3D reconstruction of colored ob-jects using a monochrome camera. 展开更多
关键词 three-dimensional shape monochrome camera RGB light projection
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Root structural remodeling under soil compaction for herbaceous plants
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作者 Qinwen Han Qingpei Yang +14 位作者 Binglin Guo Tino Colombi Junjian Wang Huifang Wu Zhipei Feng Zhi Zheng Zhenjiang Li Yue Zhang Meixu Han Qiang Li Junxiang Ding Xitian Yang Hannah M.Schneider Ying Zhao Deliang Kong 《Plant Diversity》 2026年第1期128-139,共12页
Soil compaction often imposes stress on root development and plant survival.However,root anatomical responses that enable persistent root growth and functioning under soil compaction remain unclear.We grew 10 herbaceo... Soil compaction often imposes stress on root development and plant survival.However,root anatomical responses that enable persistent root growth and functioning under soil compaction remain unclear.We grew 10 herbaceous species differing substantially in lateral root diameter,in soils with low(1.0 g cm^(-3))and high(1.4 g cm^(-3))bulk density,and assessed root traits including root biomass,anatomical structures,and respiration rates.Greater root thickening upon soil compaction was found in species with thicker first-order lateral roots,mainly due to larger cortical cell size.Both xylem vessel diameter and wall thickness increased more in compacted soils in these species.Despite these anatomical shifts,root respiration rate responded little to soil compaction across most species,likely due to the opposite investment in cortical cells and xylem vessels.Notably,root biomass,independent of root respiration rate and anatomical structures,determined whole-plant growth under soil compaction.Our study reveals two independent strategies of root response to soil compaction:anatomical remodeling for mechanical and metabolic maintenance,and root biomass investment for resource acquisition.These findings offer new insights for breeding and selecting species tolerant to soil compaction and highlight multidimensional strategies of plant adaptation to physical stress. 展开更多
关键词 root anatomy root respiration rate Soil compaction CORTEX Xylem vessel root biomass
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Novel Statistical Shape Relation and Prediction of Personalized Female Pelvis,Pelvic Floor,and Perineal Muscle Shapes
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作者 Tan-Nhu Nguyen Trong-Pham Nguyen-Huu Tien-Tuan Dao 《Computer Modeling in Engineering & Sciences》 2026年第2期1-47,共47页
Vaginal delivery is a fascinating physiological process,but also a high-risk process.Up to 85%–90%of vaginal deliveries lead to perineal trauma,with nearly 11%of severe perineal tearing.It is a common occurrence,espe... Vaginal delivery is a fascinating physiological process,but also a high-risk process.Up to 85%–90%of vaginal deliveries lead to perineal trauma,with nearly 11%of severe perineal tearing.It is a common occurrence,especially for first-time mothers.Computational childbirth plays an essential role in the prediction and prevention of these traumas,but fast personalization of the pelvis and floor muscles is challenging due to their anatomical complexity.This study introduces a novel shape-prediction-based personalization of the pelvis and floor muscles for perineal tearing management and childbirth simulation.300 subjects were selected from public Computed Tomography(CT)databases.The pelvic bone nmjmeshes were generated using a coarse-to-fine non-rigid mesh alignment procedure.The floor muscle meshes were personalized using the bone mesh deformation information.A feature-to-pelvic structure reconstruction pipeline was proposed,incorporating various strategies.Ten-fold cross-validation helped determine the optimal reconstruction strategy,regression method,and feature sizes.The mesh-to-mesh distance metric was employed for evaluating.The statistical shape relation-based strategy,coupled with multi-output ridge regression,was the optimal approach for pelvic structure reconstruction.With a feature set ranging from 3 to 38,the mean errors were 2.672 to 1.613 mm,and 3.237 to 1.415 mm in muscle attachment regions.The best-and worst-case predictions had errors of 1.227±0.959 mm and 2.900±2.309 mm,respectively.This study provides a novel approach to achieving fast personalized childbirth modeling and simulation for perineal tearing management. 展开更多
关键词 Personalized statistical shape relation shape prediction female pelvis shape pelvic floor and perineal tissue shape
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Mechanism of Pleiotropic Gene OsSP3 Regulating Root Development in Rice
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作者 YE Jing LIANG Chuyan +3 位作者 ZHAI Rongrong WU Mingming ZHANG Xiaoming YE Shenghai 《Rice science》 2026年第1期1-4,I0001-I0007,共11页
The shift from seedling transplanting to direct-seeding cultivation in rice demands robust root systems for early seedling establishment and yield stability.While the pleiotropic gene OsSP3(also designated TAC4 or SG2... The shift from seedling transplanting to direct-seeding cultivation in rice demands robust root systems for early seedling establishment and yield stability.While the pleiotropic gene OsSP3(also designated TAC4 or SG2)is known to regulate aboveground traits,including tiller angle,grain size,and panicle development,its function in root morphogenesis remains uncharacterized. 展开更多
关键词 pleiotropic gene seedling transplanting OSSP root development direct seeding cultivation root morphogenesis pleiotropic gene ossp also robust root systems
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Maize-green manure intercropping improves maize yield and P uptake by shaping the responses of roots and soil
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作者 Xin Zhao Hai Liang +4 位作者 Danna Chang Jiudong Zhang Xingguo Bao Heng Cui Weidong Cao 《Journal of Integrative Agriculture》 2026年第1期313-325,共13页
Green manuring is essential for improving soil quality and nutrient uptake.With the gradual depletion of phosphorus(P)resources,more attention is being paid to the role of green manures in cultivation systems,such as ... Green manuring is essential for improving soil quality and nutrient uptake.With the gradual depletion of phosphorus(P)resources,more attention is being paid to the role of green manures in cultivation systems,such as maize-green manure intercropping,to find possible pathways for enhancing soil P utilization.A maize-green manure intercropping experiment was started in 2009 to investigate the effects and mechanisms for enhancing P uptake and yield in maize.Three species of green manures(hairy vetch(HV),needle leaf pea(NP),sweet pea(SP))and a sole maize treatment(CK)were used,resulting in four treatments(CK,HVT,NPT,and SPT)in the experiment.During 2020-2023,the intercropping treatments enhanced maize yields in 2020 and 2021,particularly in HVT with increases of 13.7%(1.96 t ha^(-1))and 13.0%(2.13 t ha^(-1))compared with CK,respectively.Grain P accumulation of maize was significantly higher in the intercropping treatments than CK in 2020,2021,and 2023,and with an average increase of 10.6%over the four years(5.2% for NPT,10.8% for SPT and 15.9% for HVT)compared with CK.Intercropping promoted maize growth with a greater root length density and a higher organic acid release rate.HVT changed the soil properties more dramatically than the other treatments,with increases in the acid phosphatase and alkaline phosphatase activities of 29.8 and 38.5%,respectively,in the topsoil(0-15 cm),while the soil p H was reduced by 0.37 units compared to CK(p H=8.44).Intercropping treatments facilitated the conversion of non-labile P to mod-labile P and stimulated the growth of soil bacteria in the topsoil.Compared with CK,the relative abundance of Gemmatimonadota,known for accumulating polyphosphate,and Actinobacteriota,a prominent source of bioactive compounds,increased significantly in the intercropping treatments,especially in HVT and SPT.A PLS-PM analysis showed that intercropping promoted soil P mobilization and the enrichment of beneficial bacteria by regulating maize root morphology and physiology.Our results highlight that maize-green manure intercropping optimizes root traits,soil properties and bacterial composition,which contribute to greater maize P uptake and yield,providing an effective strategy for sustainable crop production. 展开更多
关键词 green manure root morphology root exudate soil P fractions soil phosphatases INTERCROPPING
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Prediction of Root Zone Temperature Dynamics at Effective Depth on Lettuce Production in Greenhouse Using Sensitivity and Feature Importance Analysis with XGBoost
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作者 Hasan Kaan Kucukerdem 《Phyton-International Journal of Experimental Botany》 2026年第1期265-289,共25页
Root-zone temperature(RZT)strongly affects plant growth,nutrient uptake and tolerance to environmental stress,making its regulation a key challenge in greenhouse cultivation in cold climates.This study aimed to assess... Root-zone temperature(RZT)strongly affects plant growth,nutrient uptake and tolerance to environmental stress,making its regulation a key challenge in greenhouse cultivation in cold climates.This study aimed to assess the potential of passive techniques,namely black polyethylene mulch and row covers,for modifying RZT dynamics in lettuce(Lactuca sativa L.)production and to evaluate the predictive performance of the eXtreme Gradient Boosting(XGBoost)algorithm.Experiments were conducted in Iğdır,Türkiye,over a 61-day period,with soil temperature continuously monitored at depths of 1-30 cm under mulched and non-mulched conditions,alongside measurements of greenhouse air temperature both with and without row covers.The application of row covers increased internal air temperature by 5.8℃,while mulching raised RZT by 0.6-1.3℃,with effects diminishing at deeper layers.XGBoost modeling achieved high predictive accuracy,with RMSE values of 0.150-0.189◦C and R^(2)values above 0.99,and feature-importance analysis indicated that neighboring soil depths were the strongest predictors of RZT.These findings show that integrating row covers and mulching can stabilize the root-zone microclimate without active heating.The XGBoost model provides a robust tool for forecasting soil temperature and supports sustainable greenhouse production in cold regions. 展开更多
关键词 GREENHOUSE machine learning MULCH root zone temperature row cover
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Rock-breaking experiments and simulations of shaped cutters in hard rock formations
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作者 Yang Guan Qingyou Liu +1 位作者 Tao Huang Zhengtong Mou 《Natural Gas Industry B》 2026年第1期93-110,共18页
To address the challenges of rapid bit failure and high drilling costs associated with hard limestone in Sichuan Basin of China,we conducted rock-breaking experiments and simulations of shaped(cylindrical,ridge,and ch... To address the challenges of rapid bit failure and high drilling costs associated with hard limestone in Sichuan Basin of China,we conducted rock-breaking experiments and simulations of shaped(cylindrical,ridge,and chopper)cutters.Rock mechanics,drillability,and acoustic emission indentation tests revealed the drilling resistance characteristics of the limestone:average uniaxial compressive strength of 202.472 MPa,tensile strength of 7.092 MPa,and drillability of 7.866.We evaluated the performance differences between the shaped cutters before introducing an efficient and innovative finite-discrete-infinite element method(FDIEM)to establish an interaction model between the shaped cutters and limestone.The simulation results indicated the following:(1)The shaped cutters demonstrated superior rock-breaking performance compared to the traditional cylindrical cutter.(2)Compared with the cylindrical cutter,the ridge cutter yielded the lowest peak indentation force and mechanical specific energy,with reductions of 8.71%and 33.83%,respectively.This confirmed that the ridge cutter had the optimal tooth profile for the target formation.Its rock-breaking mechanism relied on the convex edges to induce localized high stress in the rock,which enabled efficient rock fragmentation via a plowing mode while mitigating frictional resistance from cuttings.(3)The novel chopper cutter with its secondary step surface exerted a buffering effect on the cuttings,thereby achieving high cutting stability.This study provides theoretical and technical support for the design of personalized drill bits and the acceleration of the rate of penetration(ROP)in deep hard rock formations. 展开更多
关键词 Hard limestone shaped cutter FDIEM Rock-breaking mechanism ROP acceleration
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Polar-localized EXO70G1 regulates root development in Arabidopsis thaliana
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作者 Juan Li Zhendong Liu +9 位作者 Lixue Gong Shuju Zhao Qing Lu Shan Gao Su Jiang Xiaonan Liu Long Ma Guangyou Duan Dayong Cui Shipeng Li 《Journal of Integrative Plant Biology》 2026年第1期96-112,共17页
Cellular asymmetry,which represents a fundamental characteristic of cell polarity,is prominently illustrated by the apical-basal localization of PINFORMED(PIN)auxin efflux carriers in Arabidopsis thaliana.Although the... Cellular asymmetry,which represents a fundamental characteristic of cell polarity,is prominently illustrated by the apical-basal localization of PINFORMED(PIN)auxin efflux carriers in Arabidopsis thaliana.Although the maintenance of PIN polarity at the plasma membrane(PM)relies on endomembrane trafficking,the pivotal factors responsible for recruiting PIN proteins to the PM remain largely unknown.In this study,we discover that EXO70G1displays a polarized distribution at the PM in root cells.Acting as a putative subunit of the exocyst complex,which mediates the tethering of exocytic vesicles to the PM,EXO70G1 exhibits continuous recycling foci at the PM,and its dynamic behavior is akin to that of SEC6 and SEC8.Disruption of EXO70G1 and its homolog EXO70G2 in Arabidopsis reduces auxin accumulation and primary root length.Importantly,the recycling of PIN2 from the brefeldin A(BFA)compartment to the PM is compromised,and the abundance of PIN2 at the PM is reduced in the exo70G1 exo70G2 backgrounds.Interestingly,live-cell imaging reveals that the polarity of EXO70G1 is established during cytokinesis,prior to that of PIN2,and is maintained throughout the subsequent phases of cell elongation and differentiation.When the lipid raft was disturbed,the accumulation of EXO70G1 at the PM decreased.Our findings highlight the crucial role of EXO70G1 in root development by providing positional cues that facilitate the recycling efficiency of PIN2 to the PM. 展开更多
关键词 endomembrane trafficking EXO70 PIN polar localization root development
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SNMR with short pulses:Optimizing the kernel calculation by considering the influence of pulse shape and phase
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作者 Tobias Splith Thomas Hiller +1 位作者 Stephan Costabel Mike Müller-Petke 《Magnetic Resonance Letters》 2026年第1期43-52,共10页
In the past few years,efforts have been made to extend the sensitivity of surface nuclear magnetic resonance(SNMR)to short relaxation times,typical for strongly bound water,which,for example,occurs in partially satura... In the past few years,efforts have been made to extend the sensitivity of surface nuclear magnetic resonance(SNMR)to short relaxation times,typical for strongly bound water,which,for example,occurs in partially saturated soils.The two limiting factors for the sensitivity are the dead time after the excitation pulse and the duration of the pulse itself.To enable short pulses,while also achieving proper depths of investigation,high pulse amplitudes are needed.This makes it necessary to consider the Bloch-Siegert effect,i.e.the counter-rotating component and the parallel component of the excitation field have significant influence on the excitation.If an untuned transmitter circuit is used,the pulse shape will also be non-sinusoidal.In this paper,we demonstrate that this influences SNMR measurements with short pulses in two ways:On one hand,the pulse shape influences the phase of the fundamental frequency oscillation.On the other,at very high pulse amplitudes,other frequency components of the excitation field start to influence the excitation.The behavior of the macroscopic magnetizations in the subsurface during the pulse is simulated by solving the Bloch equations,using the pulse shape as an input.Since these calculations are computational expensive,we propose a lookup scheme that allows a time efficient modeling of the obtained SNMR data. 展开更多
关键词 Surface NMR Pulse shape Numerical modeling Bloch-Siegert effect
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ES-YOLO:Edge and Shape Fusion-Based YOLO for Tra.c Sign Detection
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作者 Weiguo Pan Songjie Du +2 位作者 Bingxin Xu Bin Zhang Hongzhe Liu 《Computers, Materials & Continua》 2026年第4期2127-2145,共19页
Traffic sign detection is a critical component of driving systems.Single-stage network-based traffic sign detection algorithms,renowned for their fast detection speeds and high accuracy,have become the dominant approa... Traffic sign detection is a critical component of driving systems.Single-stage network-based traffic sign detection algorithms,renowned for their fast detection speeds and high accuracy,have become the dominant approach in current practices.However,in complex and dynamic traffic scenes,particularly with smaller traffic sign objects,challenges such as missed and false detections can lead to reduced overall detection accuracy.To address this issue,this paper proposes a detection algorithm that integrates edge and shape information.Recognizing that traffic signs have specific shapes and distinct edge contours,this paper introduces an edge feature extraction branch within the backbone network,enabling adaptive fusion with features of the same hierarchical level.Additionally,a shape prior convolution module is designed to replaces the first two convolutional modules of the backbone network,aimed at enhancing the model's perception ability for specific shape objects and reducing its sensitivity to background noise.The algorithm was evaluated on the CCTSDB and TT100k datasets,and compared to YOLOv8s,the mAP50 values increased by 3.0%and 10.4%,respectively,demonstrating the effectiveness of the proposed method in improving the accuracy of traffic sign detection. 展开更多
关键词 Traffic sign edge information shape prior feature fusion object detection
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The effects of compressibility and target strength on shaped charge jet penetration
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作者 Qiangqiang Xiao Zhengxiang Huang +2 位作者 Xudong Zu Xin Jia Bin Ma 《Defence Technology(防务技术)》 2026年第2期244-253,共10页
The penetration of shaped charge jets into targets at high velocities is significantly influenced by the compressibility effect,while at low velocities,the strength effect becomes predominant.In the latter regime,mate... The penetration of shaped charge jets into targets at high velocities is significantly influenced by the compressibility effect,while at low velocities,the strength effect becomes predominant.In the latter regime,material strength dictates the resistance to plastic deformation and flow,a contrast to the shockwave-dominated interactions where compressibility is key.This paper presents a self-consistent compressible penetration theory that considers both the axial penetration and radial crater growth of shaped charge jets into targets.An integrated approach where the axial and radial dynamics are coupled has been proposed,influencing each other through shared physical principles rather than being treated as separate,empirically linked phenomena.The presented theory is rooted in the compressible Bernoulli equation and the linear Rankine-Hugoniot relation.These foundational equations are employed to accurately model the high-pressure shock state and subsequent material flow at the jet-target interface,providing a robust physical basis for the penetration model.Notably,it considers the target material's compressibility,which elevates the pressure at the jet-target interface beyond that observed with incompressible materials.This pressure increase is directly proportional to the target's degree of compressibility.As such,this model of compressible penetration reorients the analytical approach:rather than merely estimating penetration resistance,it determines this value from the target material's specific compressibility and yield strength.This shift from empirical correlations to a physics-based derivation of penetration resistance enhances the model's predictive power,particularly for novel target materials or engagement conditions outside established experimental datasets.This investigation establishes a quantitative link between the material's yield strength and its penetration resistance.The accuracy of this penetration resistance value is paramount,as it significantly influences the predicted crater diameter;indeed,the crater diameter's sensitivity to this resistance underscores the necessity for its precise determination.Ultimately,by integrating the yield strength of the target material,this framework enables the prediction of both the penetration depth and the resultant crater diameter from a shaped charge jet.The theory's validation involved two experimental sets:the first focused on shaped charge jet penetration into 45#steel at varied stand-offs,while the second utilized targets of high-to ultrahigh-strength steel-fiber reactive powder concrete(RPC)with differing strength characteristics.These experimental campaigns were specifically chosen to test the theory against both ductile metallic alloys,where plastic flow is significant,and advanced quasi-brittle cementitious composites,presenting a broad spectrum of material responses and penetration challenges.Resulting hole profiles derived from theoretical calculations demonstrated a strong correspondence with empirical measurements for both material types. 展开更多
关键词 shaped charge jet Penetration efficiency Compressibility influence Strength impact
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Synergistic action of the Daphnes Cortex and Liquorice Root herb pair in rheumatoid arthritis treatment:A network pharmacology strategy
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作者 Wanying Ma Yuanqing Li +1 位作者 Simeng Ding Guodong Yao 《Asian Journal of Traditional Medicines》 2026年第1期1-14,共14页
The combination of Daphnes Cortex(DC)and Liquorice Root(LR),two traditional Chinese medicinal herbs,has shown significant therapeutic effects on rheumatoid arthritis(RA),but its synergistic mechanism of action remains... The combination of Daphnes Cortex(DC)and Liquorice Root(LR),two traditional Chinese medicinal herbs,has shown significant therapeutic effects on rheumatoid arthritis(RA),but its synergistic mechanism of action remains to be elucidated.Employing a network pharmacology and molecular docking approach,this study systematically investigated the synergistic mechanism of the herb pair DC and LR in RA treatment.Active components and their corresponding targets were retrieved from the TCMSP database and relevant literature,and RA-related targets were collected from established disease databases.A total of 73 overlapping targets between DC-LR and RA were identified,among which core targets such as AKT1,TNF,and CASP3 were highlighted.GO and KEGG enrichment analyses revealed that these targets are involved in biological processes such as oxidative stress response and cell migration,and are significantly enriched in key pathways including HIF-1,TNF,and PI3K-Akt signaling pathways.Compatibility analysis further revealed that the combination of DC and LR may enhance therapeutic effects through synergistic regulation of shared targets and complementary modulation of upstream and downstream pathway components.Molecular docking confirmed strong binding affinities between core active components and key targets.This study provides a multi-dimensional“component-target-pathway”perspective on the potential synergistic anti-RA mechanism of the DC-LR herb pair,offering a theoretical basis for further experimental validation and clinical application. 展开更多
关键词 Daphnes Cortex Liquorice root rheumatoid arthritis synergistic action network pharmacology
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Influence of interface shape on microstructure and mechanical properties of Mg/Al composite plates fabricated by hot-pressing
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作者 Shi-jun TAN Bo SONG +6 位作者 Hao-hua XU Ting-ting LIU Jia SHE Sheng-feng GUO Xian-hua CHEN Kai-hong ZHENG Fu-sheng PAN 《Transactions of Nonferrous Metals Society of China》 2026年第1期124-143,共20页
A new method was proposed for preparing AZ31/1060 composite plates with a corrugated interface,which involved cold-pressing a corrugated surface on the Al plate and then hot-pressing the assembled Mg/Al plate.The resu... A new method was proposed for preparing AZ31/1060 composite plates with a corrugated interface,which involved cold-pressing a corrugated surface on the Al plate and then hot-pressing the assembled Mg/Al plate.The results show that cold-pressing produces intense plastic deformation near the corrugated surface of the Al plate,which promotes dynamic recrystallization of the Al substrate near the interface during the subsequent hot-pressing.In addition,the initial corrugation on the surface of the Al plate also changes the local stress state near the interface during hot pressing,which has a large effect on the texture components of the substrates near the corrugated interface.The construction of the corrugated interface can greatly enhance the shear strength by 2−4 times due to the increased contact area and the strong“mechanical gearing”effect.Moreover,the mechanical properties are largely depended on the orientation relationship between corrugated direction and loading direction. 展开更多
关键词 Mg/Al composite plate interface shape MICROSTRUCTURE mechanical properties TEXTURE
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Grain shape-equivalence method for compliant mechanics modeling and grinding force prediction in robotic belt grinding
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作者 Yao CHU Sijie YAN +5 位作者 Zeyuan YANG Quan ZHENG Xiaohu XU Jingyun WANG Xiangye ZHU Han DING 《Science China(Technological Sciences)》 2026年第3期146-164,共19页
Accurate mechanical modeling is essential for robotic belt grinding(RBG), a process characterized by compliant contact mechanisms that make force prediction particularly challenging. However, existing mechanical model... Accurate mechanical modeling is essential for robotic belt grinding(RBG), a process characterized by compliant contact mechanisms that make force prediction particularly challenging. However, existing mechanical models predominantly focus on macroscale compliance while neglecting grain-scale compliant motion. Moreover, abrasive grains are typically idealized as regular shapes, overlooking the inherent stochasticity of real grain geometries. This study proposes a shapeequivalence method for modeling stochastic abrasive grains and develops a multiscale compliant force model for RBG. Specifically, an individual grain is represented as a polygonal pyramid with stochastic edges that is mathematically equivalent to a cone;this method unifies the treatment of grain geometries and streamlines the modeling process. The mathematical equivalence relationship for random grain shapes is further derived based on a grain-compliant contact model. By integrating grain geometric characteristics and progressive grain wear, an analytical mechanical model that captures both the static contact force and dynamic grinding force is established, thereby describing the transition from grain-workpiece compliant interaction to belt-workpiece elastic contact. Grinding experiments were conducted using abrasive belts with different grain shape distributions to validate the model. The results demonstrated reliable predictions of the tangential grinding force and its component characteristics. Additional analyses were performed to reveal how the tangential grinding force varies with wear time and grinding parameters. 展开更多
关键词 stochastic grain shapes compliant grinding mechanism force modeling robotic belt grinding
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Isolation,identification and pathogenicity of two root rot pathogens Fusarium solani in citrus
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作者 Tao Zhu Xuzhao Luo +5 位作者 Chenxing Hao Zhimei Zhu Lian Liu Ziniu Deng Yunlin Cao Xianfeng Ma 《Horticultural Plant Journal》 2026年第1期127-135,共9页
Root rot is a prevalent soil-borne fungal disease in citrus.Citron C-05(Citrus medica)stands out as a germplasm within Citrus spp.due to its complete resistance to citrus canker and favorable characteristics such as s... Root rot is a prevalent soil-borne fungal disease in citrus.Citron C-05(Citrus medica)stands out as a germplasm within Citrus spp.due to its complete resistance to citrus canker and favorable characteristics such as single embryo and easy rooting.However,Citron C-05 was found to be highly susceptible to root rot during cultivation,with the specific pathogens previously unknown.In this study,four candidate fungal species were isolated from Citron C-05 roots.Sequence analysis of ITS,EF-1a,RPB1,and RPB2 identified two Fusarium solani strains,Rr-2 and Rr-4,as the candidates causing root rot in Citron C-05.Resistance tests showed these two pathogens increased root damage rate from 10.30%to 35.69%in Citron C-05,sour orange(Citrus aurantium),sweet orange(Citrus sinensis)and pummelo(Citrus grandis).F.solani exhibited the weak pathogenicity towards trifoliate orange(Poncirus trifoliata).DAB staining revealed none of reddish-brown precipitation in the four susceptible citrus germplasm after infection with F.solani,while trifoliate orange exhibited significant H2O2 accumulation.Trypan blue staining indicated increased cell death in the four susceptible citrus germplasm following infection with these two pathogens but not in trifoliate orange.These findings provide a comprehensive understanding of citrus root rot and support future research on the mechanisms of root rot resistance in citrus. 展开更多
关键词 Citron C-05 root rot Fusarium solani Fungal pathogen identification Multiple sequence alignment PATHOGENICITY
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Erratum:Bone Regeneration Eff cacy and Applicability of Defect-Fitting 4D Scaffolds Based on Shape Conformity in Three-dimensional Curved Bone Defects
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作者 Min-Soo Ghim Se-Jin Jang +3 位作者 Eun-Yong Choi Meiling Quan Young-Yul Kim Young-Sam Cho 《Journal of Bionic Engineering》 2026年第1期550-550,共1页
The original online version of this article was revised:The layout update for Article 758 has impacted the page range in the published issue,but did not affect the scholarly content.To ensure consistency with the orig... The original online version of this article was revised:The layout update for Article 758 has impacted the page range in the published issue,but did not affect the scholarly content.To ensure consistency with the originally assigned pages(2595-2614),we will need to publish an erratum to correct the article and restore the original page range.The original article has been corrected. 展开更多
关键词 defect fitting D scaffolds layout update shape conformity three dimensional curved bone defects bone regeneration
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