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基于Player/Stage仿真机器人的绘图系统实现
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作者 郭世龙 李文锋 李波 《微计算机信息》 北大核心 2008年第26期182-184,共3页
本文在Player/Stage仿真平台上仿真了在无线传感网络环境下的进行环境位置信息采集的机器人。利用Java客户端与仿真机器人进行Socket连接,实现了C/S工作模式的绘图系统。机器人可以传回采集的环境现场位置坐标数据,客户端实时处理这些... 本文在Player/Stage仿真平台上仿真了在无线传感网络环境下的进行环境位置信息采集的机器人。利用Java客户端与仿真机器人进行Socket连接,实现了C/S工作模式的绘图系统。机器人可以传回采集的环境现场位置坐标数据,客户端实时处理这些位置坐标数据并绘制机器人工作环境的结构地图。本绘图系统的实现有助于多机器人系统利用这些信息行进行机器人的壁障与编队。 展开更多
关键词 player/stage 机器人 绘图 JAVA
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叶尖小翼对Stage 37压气机级稳定裕度的影响
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作者 钟兢军 王缘 +1 位作者 赵傲 吴宛洋 《航空动力学报》 北大核心 2025年第3期369-379,共11页
为了进一步研究叶尖小翼对跨声速压气机级稳定工作裕度的影响,采用数值方法对NASA Stage 37压气机级加装不同叶尖小翼的效果进行了研究。通过对比原型压气机级与加装叶尖小翼压气机级的流场特性,揭示了压力面叶尖小翼的扩稳机理。研究... 为了进一步研究叶尖小翼对跨声速压气机级稳定工作裕度的影响,采用数值方法对NASA Stage 37压气机级加装不同叶尖小翼的效果进行了研究。通过对比原型压气机级与加装叶尖小翼压气机级的流场特性,揭示了压力面叶尖小翼的扩稳机理。研究结果表明:随着压力面小翼宽度增加,压气机级的稳定工作裕度分别提高了7.35%、12.27%、19.49%、12.34%。压力面小翼的扩稳机理在于有效减弱了泄漏涡与激波的干涉程度,改善了转子区域的通流情况,同时减弱了下游静子的吸力面分离,使得静子区域低能流体减少,降低了流动损失。 展开更多
关键词 叶尖小翼 stage 37压气机级 叶顶泄漏 稳定工作裕度 扩稳机理
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基于CrossStage-YOLO的跨阶段作物害虫检测 被引量:1
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作者 贾岚 徐雪环 +4 位作者 罗德弢 胡梦蝶 邓钦文 高文新 蒲海波 《南京农业大学学报》 北大核心 2025年第3期744-754,共11页
[目的]为了克服作物害虫在不同生长阶段的形态差异对模型检测造成的负面影响,本文提出了一种基于改进YOLOv7-tiny的跨阶段作物害虫检测模型CrossStage-YOLO。[方法]在YOLOv7-tiny的主干网络中结合重新构建的ELAN-D模块,实现降低计算内... [目的]为了克服作物害虫在不同生长阶段的形态差异对模型检测造成的负面影响,本文提出了一种基于改进YOLOv7-tiny的跨阶段作物害虫检测模型CrossStage-YOLO。[方法]在YOLOv7-tiny的主干网络中结合重新构建的ELAN-D模块,实现降低计算内存消耗的同时提高特征提取速度;引入感受野增强模块(RFE),提升模型对害虫特征和位置的感知能力;嵌入BiFormer注意力机制,提高模型对害虫头部、触须等细微特征的敏感度。[结果]CrossStage-YOLO的平均精度均值为88.6%,相对于原始模型提高3.0%;对成虫和幼虫检测的平均精度均值分别达到90.8%和81.1%,较原始模型分别提高3.3%和2.0%;并且模型以6.79 M的低参数量实现0.043 s的单张图片检测时间,综合性能优于主流目标检测模型。[结论]CrossStage-YOLO模型能够有效提升作物害虫不同生长阶段的检测准确率,为作物害虫检测的自动化诊断提供了可靠的技术支持。 展开更多
关键词 YOLOv7-tiny 跨阶段害虫检测 绿色农业 深度学习 智慧农业
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A Verification Theorem for Feedback Nash Equilibrium in Multiple-Player Nonzero-Sum Impulse Game 被引量:1
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作者 Ruihai Li Yaoyao Tan +1 位作者 Xiaojie Su Jiangshuai Huang 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期648-650,共3页
Dear Editor,This letter addresses the impulse game problem for a general scope of deterministic,multi-player,nonzero-sum differential games wherein all participants adopt impulse controls.Our objective is to formulate... Dear Editor,This letter addresses the impulse game problem for a general scope of deterministic,multi-player,nonzero-sum differential games wherein all participants adopt impulse controls.Our objective is to formulate this impulse game problem with the modified objective function including interaction costs among the players in a discontinuous fashion,and subsequently,to derive a verification theorem for identifying the feedback Nash equilibrium strategy. 展开更多
关键词 impulse game feedback Nash equilibrium multiple player feedback nash equilibrium strategy impulse game problem nonzero sum modified objective function impulse controlsour
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Mismatch between Reality and the NCFSE 2023:Focusing on the Pedagogical Challenges Faced by the Foundational and Preparatory Stage Teachers
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作者 Prasanna S K Chellamani 《Journal of Contemporary Educational Research》 2025年第5期201-207,共7页
Teacher education at the foundational and preparatory stages plays a crucial role in shaping early childhood learning experiences.The National Curriculum Framework for School Education(NCFSE)2023 provides a structured... Teacher education at the foundational and preparatory stages plays a crucial role in shaping early childhood learning experiences.The National Curriculum Framework for School Education(NCFSE)2023 provides a structured pedagogical approach to address challenges in these stages.However,despite these policy frameworks,teachers in Kendriya Vidyalayas(KVs)continue to face numerous pedagogical challenges.This paper aims to explore and analyze the pedagogical challenges encountered by KV teachers in foundational and preparatory stage classrooms and compare them with the challenges addressed in NCFSE 2023.Using qualitative research methods,data were collected through structured online interviews with 10 KV teachers from different campuses.This paper investigated various challenges,including classroom management,language barriers,a lack of inclusive education strategies,insufficient infrastructure,limited parental involvement,and difficulties in integrating technology into teaching practices.The findings highlight the gap between policy recommendations and ground-level implementation.Based on these insights,the study suggests recommendations such as specialized teacher training,recruitment of special educators,improved infrastructure,enhanced parental engagement,and policy-driven interventions to bridge the gap between policy frameworks and real-world classroom experiences.The study concludes that addressing these challenges through targeted reforms can create a more inclusive and effective learning environment,fostering holistic student development at the foundational and preparatory stages. 展开更多
关键词 Foundational stage teachers NCFSE 2023 NEP 2020 Pedagogical challenges Preparatory stage teachers
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The prognostic value of the 8th American Joint Committee on cancer anatomic and prognostic stage groups for penile cancer:A multicenter collaboration study
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作者 Xueying Li Yepeng Guo +8 位作者 Antonio Augusto Ornellas Jiun-Hung Geng Yonghong Li Wayne Lam Yabing Cao Zhuowei Liu Hui Han Fangjian Zhou Zaishang Li 《Asian Journal of Urology》 2025年第1期100-105,共6页
Objective The aim of this study was to investigate the value of the 8th American Joint Committee on Cancer(AJCC)anatomic and prognostic stage groups for penile cancer patients and explore whether there is room for imp... Objective The aim of this study was to investigate the value of the 8th American Joint Committee on Cancer(AJCC)anatomic and prognostic stage groups for penile cancer patients and explore whether there is room for improvement.Methods The clinical and histopathologic data from 16 centers between January 2000 and December 2021 were assessed according to the 8th AJCC anatomic and prognostic stage groups.Kaplan–Meier plots were used to estimate the disease-specific survival(DSS)of the patients.The accuracy of the staging systems was investigated using the Harrell's concordance index(C-index).Results According to the 8th AJCC anatomic and prognostic stage groups,the 5-year DSS rates for patients with stages 0is/a,I,IIA,IIB,IIIA,IIIB,and IV disease were 100%,99%,86%,81%,66%,34%,and 23%,respectively(p_(0is/a–I)=0.8,p_(I–IIA)<0.001,p_(IIA–IIB)=0.5,p_(IIB–IIIA)<0.001,p_(IIIA–IIIB)<0.001,p_(IIIB–IV)=0.004,and p_(Total)<0.001).According to the modified model 1 system,the 5-year DSS rates without survivorship overlap for patients with stages 0is/a,I,II,IIIA,IIIB,and IV disease were 100%,99%,88%,66%,34%,and 23%,respectively(p_(0is/a–I)=0.8,p_(I–II)<0.001,p_(II–IIIA)=0.002,p_(IIIA–IIIB)<0.001,p_(IIIB–IV)=0.004,and p_(Total)<0.001).Similarly,according to the modified model 2 system,the 5-year DSS rates without survivorship overlap for patients with stages 0is/a,I,II,IIIA,IIIB,and IV disease were 100%,99%,86%,66%,34%,and 23%,respectively(p_(0is/a–I)=0.8,p_(I–II)<0.001,p_(II–IIIA)=0.008,p_(IIIA–IIIB)<0.001,p_(IIIB–IV)=0.004,and p_(Total)<0.001).The C-index scores of the simple modified staging systems were not inferior to those of the AJCC anatomic and prognostic stage groups.These results were confirmed by the bootstrap internal validation.Conclusion There is still room for improvement about the 8th AJCC anatomic and prognostic stage groups.The improved models,which are more concise and convenient,have similar prediction accuracy. 展开更多
关键词 Penile cancer Prognosis Tumor-nodemetastasis Survival stage
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Scientific Protection and Training Strategies for Badminton Players after Anterior Cruciate Ligament Surgery Recovery
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作者 Xuan Zhou 《Journal of Contemporary Educational Research》 2025年第3期155-160,共6页
This study examines on badminton players following anterior cruciate ligament(ACL)surgery.It analyses the risk factors in badminton that may cause re-injury to the knee joint,such as sports postures and exercise inten... This study examines on badminton players following anterior cruciate ligament(ACL)surgery.It analyses the risk factors in badminton that may cause re-injury to the knee joint,such as sports postures and exercise intensity.Scientific and reasonable sports protection measures and training plans are formulated,including correcting sports postures and reasonably controlling exercise intensity and frequency.Rehabilitation training is carried out in stages,and the training intensity and frequency are gradually adjusted according to the recovery situation.Through scientific protection and training,the risk of re-injury to athletes can be reduced,and they can be helped to restore their best sports conditions.At the same time,future research directions are prospected,covering personalized rehabilitation programs,application of new technologies,and research on psychological factors. 展开更多
关键词 ACL surgery Badminton players Sports protection Training plan
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Orthorexia Nervosa Risk,Body Image Perception,and Associated Predictors Among Adolescent Football Players from Poland and Türkiye
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作者 Wiktoria Staśkiewicz-Bartecka Samet Aktaş +2 位作者 Grzegorz Zydek Marek Kardas Oskar Kowalski 《International Journal of Mental Health Promotion》 2025年第5期649-665,共17页
Background In light of growing concern over eating disorders among young athletes amid cultural and social pressures,this study aimed to assess the prevalence of orthorexia nervosa(ON)risk and evaluate body image perc... Background In light of growing concern over eating disorders among young athletes amid cultural and social pressures,this study aimed to assess the prevalence of orthorexia nervosa(ON)risk and evaluate body image perception and its predictive factors among young football players from Poland and Türkiye.Methods The study involved 171 players aged 15–18 years,recruited from football academies in Poland and Türkiye.The Polish and Turkish versions of the Body-Esteem Scale for Adolescents and Adults(BESAA)were administered to assess body image perception,while the Düsseldorf Orthorexia Scale(DOS)was used to measure ON risk.Anthropometric measurements were taken to calculate Body Mass Index(BMI),which was then referenced to centile charts to determine nutritional status.Results Results indicated that 13%of participants exhibited characteristics of ON,with an additional 26%classified as at elevated risk.Comparative analysis revealed no significant differences in ON prevalence between Polish and Turkish players(p=0.938)and no age-related differences(p=0.694).Among Polish players,a significant positive association emerged between BMI(relative to centile charts)and overall appearance evaluation(BE-Appearance)(p=0.008,partialη^(2)=0.10).This relationship was not observed in Turkish players.Moreover,analysis of ON risk predictors—including age,nationality,nutritional status,and body image—did not identify any single variable as a definitive predictor(all p-values>0.05),with a low predictive capacity(McFadden’s R^(2)=0.03).Conclusion The study revealed a significant risk of ON among young footballers with no clear predictors. 展开更多
关键词 Eating disorders football player orthorexia nervosa ATHLETES mental health
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Sexually differentiated decision-making involves faster recruitment in the early stages for the Tibetan antelopes Pantholops hodgsonii
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作者 Qin Zhu Jian Guan +6 位作者 Tianya Lei Kun Xuan Sile Guo Yumeng Zhao Changjian Fu Le Yang Zhongqiu Li 《Current Zoology》 2025年第1期124-135,共12页
Group living is widespread across diverse taxa,and the mechanisms underlying collective decision-making in contexts of variable role division are critical for understanding the dynamics of group stability.While studie... Group living is widespread across diverse taxa,and the mechanisms underlying collective decision-making in contexts of variable role division are critical for understanding the dynamics of group stability.While studies on collective behavior in small animals such as fish and insects are well-established,similar research on large wild animals remains challenging due to the limited availability of sufficient and systematic field data.Here,we aimed to explore the collective decision-making pattern and its sexual difference for the dimorphic Tibetan antelopes Pantholops hodgsonii(chiru)in Xizang Autonomous Region,China,by analyzing individual leadership distribution,as well as the joining process,considering factors such as calving stages and joining ranks.The distinct correlations of decision participants’ratio with group size and decision duration underscore the trade-off between accuracy and speed in decision-making.Male antelopes display a more democratic decision-making pattern,while females exhibit more prompt responses after calving at an early stage.This study uncovers a partially shared decision-making strategy among Tibetan antelopes,suggesting flexible self-organization in group decision processes aligned with animal life cycle progression. 展开更多
关键词 calving stage DECISION-MAKING LEADERSHIP sexual differences Tibetan antelopes
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Application of the modified Byars staged procedure for severe hypospadias repair
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作者 Qi-Gen Xie Ting-Ting Xue +4 位作者 Xu-Ren Chen Zhao-Ying Li Zhe Xu Zuo-Qing Li Peng Luo 《Asian Journal of Andrology》 2025年第1期65-71,共7页
This study aimed to introduce a modified Byars staged procedure and investigate its application value in patients with severe hypospadias.We retrospectively analyzed the clinical data of patients with severe hypospadi... This study aimed to introduce a modified Byars staged procedure and investigate its application value in patients with severe hypospadias.We retrospectively analyzed the clinical data of patients with severe hypospadias admitted to the First Affiliated Hospital of Sun Yat-sen University(Guangzhou,China)between October 2012 and October 2022.In total,31 patients underwent the conventional Byars procedure(conventional group),and 45 patients underwent the modified Byars staged procedure(modified group).Our modified strategy was built upon the standard Byars procedure by incorporating glansplasty during the first stage and employing a Y-shaped flap in conjunction with a glandular tunnel for urethroplasty during the second stage.Notably,there were no statistically significant differences in the preoperative baseline characteristics,duration of surgery,amount of blood loss,or occurrence of postoperative complications,including urethral fistula,stricture and diverticulum,or penile curvature,between the conventional and modified groups.However,there was a significantly lower incidence of coronal sulcus fistula(0 vs 16.1%,P=0.02)and glans dehiscence(0 vs 12.9%,P=0.02)in the surgical group than that in the conventional group.In addition,the modified group exhibited a notably greater rate of normotopic urethral opening(100.0%vs 83.9%,P=0.01)and a higher mean score on the Hypospadias Objective Penile Evaluation(HOPE;mean±standard error of mean:8.6±0.2 vs 7.9±0.3,P=0.02)than did the conventional group.In conclusion,the modified Byars staged procedure significantly reduced the risks of glans dehiscence and coronal sulcus fistula.Consequently,it offers a promising approach for achieving favorable penile esthetics,thereby providing a reliable therapeutic option for severe hypospadias. 展开更多
关键词 byars glans dehiscence severe hypospadias staged procedure TUNNEL URETHROPLASTY
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Research on Risk Management in the Decision- Making Stage of a Project Based on DPSIR
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作者 Yujie Zhang 《Proceedings of Business and Economic Studies》 2025年第1期28-37,共10页
With the growth of the construction industry,risk management in construction projects has garnered significant attention from the academic community.Effective risk management during the decision-making stage can great... With the growth of the construction industry,risk management in construction projects has garnered significant attention from the academic community.Effective risk management during the decision-making stage can greatly enhance project management efficiency.This paper integrates the AHP-entropy value method and constructs a risk management model based on the DPSIR framework for construction projects.The model is applied to evaluate and analyze the risk level of the decision-making stage in a navigation and electricity hub project in Chongqing Municipality.The results demonstrate the scientific validity and effectiveness of the proposed model. 展开更多
关键词 DPSIR Construction projects Decision stage Risk management AHP-entropy method
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Research on the estimation of wheat AGB at the entire growth stage based on improved convolutional features
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作者 Tao Liu Jianliang Wang +7 位作者 Jiayi Wang Yuanyuan Zhao Hui Wang Weijun Zhang Zhaosheng Yao Shengping Liu Xiaochun Zhong Chengming Sun 《Journal of Integrative Agriculture》 2025年第4期1403-1423,共21页
The wheat above-ground biomass(AGB)is an important index that shows the life activity of vegetation,which is of great significance for wheat growth monitoring and yield prediction.Traditional biomass estimation method... The wheat above-ground biomass(AGB)is an important index that shows the life activity of vegetation,which is of great significance for wheat growth monitoring and yield prediction.Traditional biomass estimation methods specifically include sample surveys and harvesting statistics.Although these methods have high estimation accuracy,they are time-consuming,destructive,and difficult to implement to monitor the biomass at a large scale.The main objective of this study is to optimize the traditional remote sensing methods to estimate the wheat AGBbased on improved convolutional features(CFs).Low-cost unmanned aerial vehicles(UAV)were used as the main data acquisition equipment.This study acquired image data acquired by RGB camera(RGB)and multi-spectral(MS)image data of the wheat population canopy for two wheat varieties and five key growth stages.Then,field measurements were conducted to obtain the actual wheat biomass data for validation.Based on the remote sensing indices(RSIs),structural features(SFs),and CFs,this study proposed a new feature named AUR-50(multi-source combination based on convolutional feature optimization)to estimate the wheat AGB.The results show that AUR-50 could estimate the wheat AGB more accurately than RSIs and SFs,and the average R^(2) exceeded 0.77.In the overwintering period,AUR-50_(MS)(multi-source combination with convolutional feature optimization using multispectral imagery)had the highest estimation accuracy(R^(2) of 0.88).In addition,AUR-50 reduced the effect of the vegetation index saturation on the biomass estimation accuracy by adding CFs,where the highest R^(2) was 0.69 at the flowering stage.The results of this study provide an effective method to evaluate the AGB in wheat with high throughput and a research reference for the phenotypic parameters of other crops. 展开更多
关键词 WHEAT above-ground biomass UAV entire growth stage convolutional feature
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Staged dendrite suppression for high safe and stable lithium-sulfur batteries
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作者 Jun Jiang Zhenjie Lu +12 位作者 Yanwen Ding Shujun Liu Zhijie Qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang Pan Xiong Xin Wang Junwu Zhu Yongsheng Fu 《Journal of Energy Chemistry》 2025年第1期674-683,共10页
The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur batteries.Herein,we propose a dual-action strategy to address the lithiu... The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur batteries.Herein,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene (PP) separator.The uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition stage.Most importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance(145.88 MPa) of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium dendrite.The Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm^(-2)with a polarization voltage of only 29.3 mV.Additionally,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity attenuation.The improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect. 展开更多
关键词 Lithium-sulfur batteries staged dendrite suppression Shuttle effect Surface-negatively-charged nanodiamond
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Design of mobile stage location system based on two-dimensional laser radar
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作者 WANG Bo ZHU Ping +1 位作者 ZHENG Qingsong YANG Jiaqi 《High Technology Letters》 2025年第1期20-31,共12页
This paper addresses the design problem of an embedded mobile stage location system based on a two-dimensional laser radar.The mobile stage is a piece of important performance equipment in art performances,and the pos... This paper addresses the design problem of an embedded mobile stage location system based on a two-dimensional laser radar.The mobile stage is a piece of important performance equipment in art performances,and the positioning problem is one of the key issues in the control of the mobile stage.Both hardware and software are developed for the mobile stage.The hardware of the location system consists of a laser radar,an embedded control board,a wireless router,and a motion control unit.The software of the location system includes embedded software and human-machine interface(HMI),and they are designed to achieve the functions of real-time positioning and monitoring.First,a novel landmark identification method is presented based on the landmark reflection intensities and shapes.Then,the initial pose of the mobile stage is calculated by using the triangle matching algorithm and the least squares method.A distributed fusion Kalman filtering algorithm is applied to fuse landmark information and odometer information to achieve real-time positioning of the mobile stage.The designed system has been implemented in a practical mobile stage,and the results demonstrate that the location system can achieve a high positioning precision in both the stationary and moving scenarios. 展开更多
关键词 mobile stage positioning laser radar Kalman filter distributed fusion
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Transcriptomic profiling of cardiac development in Bama Xiang pigs across key developmental stages
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作者 Sheng-Nan Wang Wen-Jie Tian +4 位作者 Deng-Ke Pan Tang Hai Yue-Hui Ma Dan-Dan Wang Lin Jiang 《Zoological Research》 2025年第3期634-646,共13页
Pigs have emerged as valuable large-animal models for cardiac xenotransplantation;however,the temporal dynamics of myocardial development in this species remains insufficiently defined.This study analyzed gene express... Pigs have emerged as valuable large-animal models for cardiac xenotransplantation;however,the temporal dynamics of myocardial development in this species remains insufficiently defined.This study analyzed gene expression patterns across four key developmental stages(neonatal,juvenile,sexual maturity,and adulthood)to delineate the molecular mechanisms driving porcine myocardial development.Increases in heart weight were accompanied by proportional expansion of myocardial fiber area and chamber size,reflecting coordinated structural development.Transcriptomic profiling of myocardial tissue by RNA sequencing(RNA-seq)identified 2189 differentially expressed genes(DEGs)across stage comparisons.Short time-series expression miner(STEM)analysis classified these DEGs into four major expression clusters enriched in pathways associated with myocardial development,immune responses,cell proliferation,and metabolic processes.Among 359 DEGs conserved across all developmental stages,six candidate genes were strongly associated with myocardial development.Reverse transcription-quantitative real-time polymerase chain reaction(RT-qPCR)confirmed a significant correlation between the expression of these candidate genes and myocardial development in porcine tissue.These findings establish a transcriptomic framework for porcine myocardial maturation and provide a molecular basis for advancing cardiac xenotransplantation. 展开更多
关键词 Cardiac tissue Bama Xiang pig Multiple stages Heart development TRANSCRIPTOMICS
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Nonlinear effect analysis and compensation based on improved friction observer for torque rotating stage
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作者 Yingjie Jia Bo Liu +1 位作者 Hui Tang Yuzhang Wei 《Nanotechnology and Precision Engineering》 2025年第3期138-148,共11页
In semiconductor precision packaging and other applications involving alignment of automated equipment,the nonlinear motion caused by structural characteristics and friction effects on torque-type rotating motion stag... In semiconductor precision packaging and other applications involving alignment of automated equipment,the nonlinear motion caused by structural characteristics and friction effects on torque-type rotating motion stages seriously affects output accuracy and stability.To solve this problem,the motion characteristics of a rotating stage and the mechanism by which friction nonlinearity influences accuracy are analyzed in detail.In addition,a compound control strategy based on a kinematic model and the Stribeck friction model is designed.A friction disturbance observer based on output position feedback is improved for simple parameter tuning.Finally,an experimental system is constructed to carry out validation tests,including identification of nonlinear characteristics and performance comparisons.The experimental results show that the linear tracking error of the torque-type rotating stage is less than 1.47µm after adoption of the proposed model-based composite control strategy,and the corresponding rotary angle deviation is less than 0.0153°.The linearity of output motion is increased to 97.59%and the error compensation effect is improved by 51.6%compared with the PID control method.The experimental results confirm that the analysis method adopted here and the proposed compensation strategy can effectively reduce frictional nonlinearity and improve motion accuracy.The proposed method can also be applied to other precision electromechanical systems. 展开更多
关键词 Rotating stage Mechanical analysis Frictional nonlinear effect Disturbance observation
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Effectiveness of nulliparous women’s different childbirth positions during the second stage of labor:A systematic review and network meta-analysis
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作者 Hongyan Liu Lingling Li +5 位作者 Xiaojiao Wang Xinli Zhu Liping Sun Chunxiang Zhu Hui Min Chunyi Gu 《International Journal of Nursing Sciences》 2025年第3期268-275,共8页
Objectives A systematic review and network meta-analysis was conducted to evaluate the effectiveness of different childbirth positions in reducing the duration of the second stage of labor,providing evidence-based ins... Objectives A systematic review and network meta-analysis was conducted to evaluate the effectiveness of different childbirth positions in reducing the duration of the second stage of labor,providing evidence-based insights for obstetric institutions to guide interventions related to childbirth positions.Methods A comprehensive literature search was conducted in databases,including PubMed,Web of Science,the Cochrane Library,Embase,Wanfang Databases,China National Knowledge Infrastructure Databases(CNKI),China Science and Technology Journal Database(CSTJ),and China Biology Medicine disc(CBMdisc)to identify studies on the effectiveness of different childbirth positions in reducing the duration of the second stage of labor.The search included randomized controlled trials published from database inception to September 30,2024.The Cochrane risk-of-bias tool was used to assess the quality of the studies.Two independent reviewers screened the literature,extracted data,and evaluated study quality.Subsequently,a network meta-analysis was performed using STATA software.The study protocol has been registered in PROSPERO(CRD42023428217).Results This study analyzed data from 25 randomized controlled trials involving 9,844 women.The findings indicated that in comparison to lithotomy position,free position(MD=20.53,95%CI[11.38,29.68])and upright position(MD=−24.13,95%CI[−42.94,-5.32])were found to be superior in reducing the duration of the second stage of labor.Free position outperformed kneeling position(MD=21.48,95%CI[4.67,38.28])and squatting position(MD=23.43,95%CI[1.88,44.97]);upright position was superior to kneeling position(MD=−25.08,95%CI[−46.93,−3.22]);semirecumbent position surpassed squatting position(MD=19.71,95%CI[2.05,37.38]);and upright position was also superior to squatting position(MD=−27.03,95%CI[−51.48,−2.57]).According to the surface under the cumulative ranking curve(SUCRA),the upright position emerged as the most effective for reducing the duration of the second stage of labor(87.4%),followed by free position(81.1%),semirecumbent position(70.0%),and lateral position(62.3%).Conclusion These findings offer valuable insights for midwifery practice and help inform future research directions.Considering the limitations of this review,more larger-scale,multicenter randomized controlled trials are warranted to further evaluate the relative effectiveness of different childbirth positions in reducing the duration of the second stage of labor. 展开更多
关键词 CHILDBIRTH POSITION Nulliparous women Network meta-analysis Second stage of labor
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Rhizosphere bacterial communities of Agriophyllum squarrosum(L.)Moq.during different developmental stages
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作者 ZHANG Shengnan GAO Haiyan +7 位作者 YANG Shanshan ZHANG Lei YAN Deren HUANG Haiguang YANG Zhiguo LI Junwen TANG Yuekun XU Hongbin 《Journal of Arid Land》 2025年第9期1282-1296,共15页
The rhizosphere bacteria play crucial roles in plant health and growth as they are involved in assimilating nutrients and resisting adverse conditions such as nutrient stress,drought,and wind erosion.Agriophyllum squa... The rhizosphere bacteria play crucial roles in plant health and growth as they are involved in assimilating nutrients and resisting adverse conditions such as nutrient stress,drought,and wind erosion.Agriophyllum squarrosum(L.)Moq.is a pioneer plant used in sand fixation due to its strong resistance to drought and wind erosion.However,the bacterial community characteristics and ecological function in the rhizosphere of A.squarrosum are poorly understood.In this study,soil samples were collected from different developmental stages(seedling stage,vegetative stage,reproductive stage,and withering stage)of A.squarrosum.Illumina Miseq sequencing was used to detect differences in soil bacterial abundance.The Phylogenetic Investigation of Communities by Reconstruction of Unobserved States(PICRUSt)program was used to predict bacterial functions,and the relationships among bacteria,functional populations,and soil nutrients were examined using a heatmap analysis.The results showed that the Shannon and Sobs indices of rhizosphere bacteria were significantly higher during the reproductive stage than during the other stages.Pantoea sp.(7.03%)was the dominant genus during the seedling stage;Arthrobacter sp.was the dominant genus during the vegetative(13.94%),reproductive(7.57%),and withering(12.30%)stages.The relative abundances of Chloroflexi,Acidobacteria,and Gemmatimonadetes were significantly high during the reproductive stage.According to the PICRUSt analysis,membrane transport,signal transduction,and environmental adaptation of the bacterial functional population occurred during the seedling stage.Carbohydrate metabolism increased during the vegetative stage,while energy metabolism,lipid metabolism,and biosynthesis of other secondary metabolites of the bacterial functional population significantly increased during the reproductive stage.The abundances of bacterial communities,functional genes,and soil nutrients were synergistically altered during various developmental stages.Our findings suggest that the developmental stages of A.squarrosum play a significant role in defining the composition and structure of bacterial communities in the rhizosphere.The results will provide a basis for better prediction and understanding of soil bacterial metabolic potential and functions of A.squarrosum rhizosphere in sandy areas. 展开更多
关键词 bacterial diversity developmental stage DROUGHT functional prediction soil nutrient wind erosion
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Association between lifestyle factors and disease progression in patients with colorectal polyps and early-stage cancer
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作者 Fang-Fang Lin Jun-Ting Ye +2 位作者 Xia-Yan Mao Xue-Juan Mao Hui-Hua Ye 《World Journal of Gastrointestinal Oncology》 2025年第8期277-285,共9页
BACKGROUNDColorectal cancer(CRC)typically progresses from benign colorectal polyps,whichrepresent a precursor to malignancy.Identifying the factors influencing thisprogression is crucial for early intervention and pre... BACKGROUNDColorectal cancer(CRC)typically progresses from benign colorectal polyps,whichrepresent a precursor to malignancy.Identifying the factors influencing thisprogression is crucial for early intervention and prevention.Although genetic andenvironmental factors have been widely studied,the role of lifestyle factors suchas physical activity,diet,smoking,sleep,and stress remains underexplored,especially in patients with early stage CRC or polyps.Recent evidence suggeststhat lifestyle behaviors may influence cancer progression by modulating inflammatorypathways,metabolic health,and immune function.For instance,highlevels of physical activity are linked to a reduced risk of CRC development,whereas poor dietary habits,smoking,and inadequate sleep have all beenimplicated in increased cancer risk and progression.Moreover,early-stage CRCpatients,who are often asymptomatic or have minimal symptoms,may particularlybenefit from lifestyle modifications to slow disease progression andimprove overall prognosis.The gap in understanding the specific influence ofthese lifestyle factors on colorectal polyps and early stage cancer progressionunderscores the need for comprehensive studies.By assessing several modifiablelifestyle factors and their association with disease progression,clinicians canidentify practical intervention points.These interventions could ultimately reducethe need for more aggressive treatments and improve the long-term outcomes inaffected patients.AIMTo investigate the association between lifestyle factors and disease progression inpatients with colorectal polyps and early stage cancer.METHODSIn this observational study conducted from January 2022 to December 2023,werecruited 120 patients with colorectal polyps or early stage cancer from Jiangshan People's Hospital.Lifestyle factors,including physical activity,dietary patterns,smoking status,sleep quality,andstress levels,were assessed using validated questionnaires.Disease progression was evaluated using standardizedfollow-up colonoscopies and pathological examinations.Cox proportional hazards models were used to analyzethe association between lifestyle factors and disease progression after adjusting for potential confounders.RESULTSDuring the median follow-up of 18.4 months,42(35.0%)patients experienced disease progression.High levels ofphysical activity were associated with reduced progression risk[adjusted hazard ratio(HR)0.55,95%confidenceinterval(CI):0.38-0.80,P=0.002]compared to low activity levels.High adherence to a healthy dietary patternshowed similar protective effects(adjusted HR 0.62,95%CI:0.43-0.89,P=0.009).Current smoking(adjusted HR1.92,95%CI:1.35-2.73,P<0.001)and poor sleep quality(adjusted HR 1.38,95%CI:1.05-1.82,P=0.021)wereassociated with increased progression risk.The impact of lifestyle factors was particularly pronounced in patientsyounger than 60 years and those with multiple polyps at baseline.CONCLUSIONThis study demonstrated significant associations between lifestyle factors and disease progression in colorectalpolyps and early stage cancer.Physical activity,dietary patterns,smoking status,and sleep quality have emergedas key modifiable factors influencing disease progression.These findings support the integration of lifestyleassessments and modifications in the clinical management of patients with colorectal neoplasia. 展开更多
关键词 Colorectal polyps Disease progression Lifestyle factors Early stage cancer Health behavior
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Tumor markers and multimodal magnetic resonance imaging in predicting rectal cancer stage and differentiation
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作者 Peng Wang Jun Han +3 位作者 Wen-Na Zhao Fan Wu Sheng-He Zhang Yi-Juan Huang 《World Journal of Gastrointestinal Oncology》 2025年第8期126-135,共10页
BACKGROUND Rectal cancer is one of the common digestive system malignant tumors around the world.Its early diagnosis and staging are crucial for rectal cancer treatment and prognosis.In recent years,tumor markers have... BACKGROUND Rectal cancer is one of the common digestive system malignant tumors around the world.Its early diagnosis and staging are crucial for rectal cancer treatment and prognosis.In recent years,tumor markers have gradually received attention in early screening,treatment monitoring and prognostic evaluation of cancer,but their predictive role in rectal cancer staging and differentiation is still unclear.AIM To assess the prognostic value of tumor markers alpha-fetoprotein(AFP)cancer antigen 72-4(CA72-4),carbohydrate antigen 19-9(CA19-9),and carcinoembryonic antigen(CEA),alongside multimodal magnetic resonance imaging(MRI),for staging and differentiating rectal cancer in patients.METHODS This study retrospectively analyzed 167 patients with rectal cancer who were treated at our institution from January 2020 to December 2024.Each patient underwent serological testing and multimodal MRI for diagnosis.Histopathological examination after surgical resection or imaging based on follow-up was used as the gold standard.According to the T stage and differentiation degree,patients were divided into low stage group(T1-T2)and high stage group(T3-T4).In addition,they were divided into low-differentiation groups and high-differentiation groups according to their differentiation degree.We compared the accuracy,sensitivity and specificity of tumor marker levels and MRI in rectal cancer stage and differentiation.RESULTS The study's findings indicate that in the context of rectal cancer T staging,there is substantial concordance between MRI and clinicopathological assessments,with a Kappa coefficient of 0.789(P<0.001).Similarly,for various degrees of tumor differentiation,MRI and clinicopathological evaluations demonstrated substantial agreement,with a Kappa coefficient of 0.651(P<0.001).Notably,the concentrations of tumor markers CA19-9,CA72-4,CEA,and AFP were significantly elevated in the T3-T4 stage compared to the T1-T2 stage.Furthermore,these markers were significantly higher in the low-differentiation group compared to the high-differentiation group(P<0.05).The combined use of tumor markers and MRI for preoperative T staging of rectal cancer yielded a diagnostic sensitivity of 93.7%and a specificity of 94.6%,as evidenced by the receiver operating characteristic analysis,with an area under the curve of 0.947.For tumor differentiation,the diagnostic sensitivity and specificity were 93.6%and 97.1%,respectively,with an area under the curve of 0.978(95%confidence interval:0.946-1.000),surpassing the accuracy of individual detection methods.CONCLUSION The CA19-9,CA72-4,CEA and AFP tumor markers combined with multimodal MRI have high sensitivity and specificity in diagnosing rectal cancer stage and differentiation.Their diagnostic efficacy is significantly better than that of single tests,which can effectively improve the predictive ability of rectal cancer stage and differentiation,provide a more reliable diagnostic reference for clinical practice,and have important clinical significance. 展开更多
关键词 Multimodal magnetic resonance imaging Rectal cancer T stage Tumor markers DIFFERENTIATION
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