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微创手术机器人RCM机械臂广义运动学误差建模与补偿研究
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作者 刘芬 王睿 +1 位作者 黄芳 桑宏强 《机械传动》 北大核心 2025年第8期46-52,共7页
【目的】针对几何误差和非几何误差导致远程运动中心(Remote Center of Motion,RCM)机械臂运动过程中产生RCM约束点位置误差,进而存在一定的安全性问题,提出了一种微创手术机器人RCM机械臂广义运动学误差建模与补偿方法。【方法】首先,... 【目的】针对几何误差和非几何误差导致远程运动中心(Remote Center of Motion,RCM)机械臂运动过程中产生RCM约束点位置误差,进而存在一定的安全性问题,提出了一种微创手术机器人RCM机械臂广义运动学误差建模与补偿方法。【方法】首先,基于切比雪夫多项式建立表征几何误差和非几何误差引起的关节相关运动学误差的误差模型;然后,通过最小二乘法对误差模型中的多项式系数和运动学参数误差进行辨识;最后,采用关节空间补偿的方法,以降低RCM约束点位置误差。【结果】试验结果表明,补偿后的RCM约束点位置误差由2.7261 mm减小到0.6415 mm,减小了约76.5%。 展开更多
关键词 rcm机械臂 误差建模 参数辨识 切比雪夫多项式
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基于数据驱动的水电站设备智能RCM维修决策支持系统
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作者 姚侃 吕柏昂 董玉亮 《水电与抽水蓄能》 2025年第2期34-41,共8页
以可靠性为中心的维修决策方法可以提升发电企业维修管理水平,提高设备的可靠性和可用率,降低维修费用,而基于数据驱动的水电站设备智能RCM维修决策支持系统则是确保RCM维修决策方法高效实施的支撑平台。从改进的RCM维修决策流程、系统... 以可靠性为中心的维修决策方法可以提升发电企业维修管理水平,提高设备的可靠性和可用率,降低维修费用,而基于数据驱动的水电站设备智能RCM维修决策支持系统则是确保RCM维修决策方法高效实施的支撑平台。从改进的RCM维修决策流程、系统总体设计和应用对数据驱动的水电站设备智能RCM维修决策支持系统进行了阐述。首先,提出了考虑设备状态动态变化的改进的RCM维修决策流程;然后,从系统总体构架、工作流程和数据逻辑三个方面对RCM维修决策支持系统进行了详细的设计;最后,重点针对FMEA分析、故障统计分析、基于RPN综合评估的智能维修决策三个模块,说明了数据驱动的水电站设备智能RCM维修决策支持系统的应用。 展开更多
关键词 水电站设备 维修决策支持系统 rcm FMEA 数据驱动 智能逻辑决断
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Application of Functional Group Migration Strategies in Photodriven Difunctionalization of Unsaturated Hydrocarbons
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作者 He Chonglong Zhou Youkang +1 位作者 Duan Xinhua Liu Le 《有机化学》 北大核心 2025年第5期1478-1508,共31页
Difunctionalization of unsaturated hydrocarbons is a pivotal synthetic strategy enabling the conversion of alkenes and alkynes into high value-added compounds.It allows for the introduction of two functional groups in... Difunctionalization of unsaturated hydrocarbons is a pivotal synthetic strategy enabling the conversion of alkenes and alkynes into high value-added compounds.It allows for the introduction of two functional groups into the unsaturated bond in a single step,facilitating the efficient construction of complex molecular architectures,which has been widely utilized in material chemistry,pharmaceutical and fine chemical synthesis.Recently,significant progress has been made via free radical-mediated difunctionalization due to the extensive application of photocatalysis.However,highly selective difunc-tionalization reactions still remain challenging.The research progress of selective difunctionalization of unsaturated hydro-carbons using a free radical addition/functional group migration strategy over the past decade is summarized,and synthetic strategies and key reaction steps are systematically elaborated. 展开更多
关键词 visible-light-driven unsaturated hydrocarbon functional group migration difunctionalization
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Lactylation of PARP1 at K192 inhibits the migration and proliferation of ovarian cancer cells
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作者 SU Ning CAO Ying +7 位作者 ZHANG Shuping WU Shaojun SUN Hongzhan TANG Xuejun YUAN Donglan ZHANG Dong YANG Lili YING Xiaoyan 《南京医科大学学报(自然科学版)》 北大核心 2025年第9期1219-1228,1241,共11页
Objective:Ovarian cancer(OC)ranks among the leading causes of mortality among the female cancers worldwide.Numerous studies have explored the development and progression of OC at multiple genetic regulatory levels.How... Objective:Ovarian cancer(OC)ranks among the leading causes of mortality among the female cancers worldwide.Numerous studies have explored the development and progression of OC at multiple genetic regulatory levels.However,relatively few studies have explored the impact of post-translational modifications(PTM)on OC progression,which is essential for uncovering new therapeutic targets.This study aimed to systematically identify the key PTM types involved in OCprogression,and to explore and evaluate their translational potential as therapeutic targets.Methods:First,we utilized multiple general PTM antibodies to compare gross PTM levels between normal ovarian and OC tissues from clinical females.After identifying lactylation as the PTM with the most significant differences,we selected representative samples for label-free mass spectrometry to identify specific lactylation sites.Next,we transfected A2780(OC)cells with either wild-type(WT)or mutant(K192A[Q])poly(ADP-ribose)polymerase 1(PARP1)conjugated to enhanced green fluorescent protein(EGFP)with a StrepⅡpeptide tag and assessed various cellular indexes related to cell proliferation(clonogenicity assay),migration(scratch wound healing assay),and reactive oxygen species levels.Results:Pan-lactylation was significantly upregulated in clinical OC samples,with PARP1 lactylation at K192 being one of the most common modifications.The growth and migration of A2780 cells were markedly suppressed by overexpressing PARP1-WT but not mutant PARP1.Overexpressing PARP1 significantly downregulated the phosphorylation of extracellular signal-regulated kinases 1/2(ERK1/2).Conclusion:This study uncovered a novel PTM of PARP1 in OC,lactylation,and demonstrated that lactylation at K192 is crucial in regulating OC cell growth and migration via the ERK1/2 pathway.Further investigations are required to elucidate the broader functional implications of PARP1 lactylation and its therapeutic potential. 展开更多
关键词 PARP1 lactylation migration PROLIFERATION ovarian cancer cells
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基于RCM分析磨煤机分离器爆燃原因与防范措施
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作者 吴戈杨 《今日自动化》 2025年第4期88-90,共3页
制粉系统是燃煤电厂主要辅机之一,其运行的稳定性对锅炉的燃烧工况有着直接的影响。直吹式制粉系统爆燃,不仅会造成磨煤机及其附件的损坏,还会对锅炉的安全造成较大影响。文章基于RCM对磨煤机分离器爆燃的原因进行了分析,通过系统性的分... 制粉系统是燃煤电厂主要辅机之一,其运行的稳定性对锅炉的燃烧工况有着直接的影响。直吹式制粉系统爆燃,不仅会造成磨煤机及其附件的损坏,还会对锅炉的安全造成较大影响。文章基于RCM对磨煤机分离器爆燃的原因进行了分析,通过系统性的分析,防范潜在的故障,减少分离器爆燃的发生,实现维修资源的合理配置。文章概括了广东大唐国际雷州发电有限责任公司1号、2号机组的情况,梳理了磨煤机分离器爆燃的经过及处理过程,提出了防范磨煤机分离器爆燃的措施,旨在可为磨煤机的安全、稳定、可靠性提供借鉴。 展开更多
关键词 rcm 磨煤机 分离器爆燃
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基于RCM的“动态维修模式”研究与实践
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作者 陈强 耿涛 +3 位作者 靳晓姣 赵节芳 刘艳 张春杨 《智慧轨道交通》 2025年第4期83-87,共5页
当前产品运用过程中常用的维修方式存在过修或欠修问题,容易导致质量损失和维修成本增加。针对上述问题,文章提出了基于以可靠性为中心的维修(RCM)的“动态维修模式”。基于RCM的基本方法确定了“动态维修模式”的模型,以产品可靠性为基... 当前产品运用过程中常用的维修方式存在过修或欠修问题,容易导致质量损失和维修成本增加。针对上述问题,文章提出了基于以可靠性为中心的维修(RCM)的“动态维修模式”。基于RCM的基本方法确定了“动态维修模式”的模型,以产品可靠性为基础,系统分析产品的故障模式、原因和影响,针对不同的故障类型,通过故障率监测、故障率曲线求取与故障率趋势预测、LCC评估分析等方式,并根据是否有PHM或离线健康诊断功能等不同情况提出了相应的维修策略。应用逻辑决断的方法,判断出产品各类故障的最佳维修方案,可为制定预防性维修需求和优化修程修制内容提供科学依据。依据该模型对各个逻辑判断点的实现方式进行了深入分析,并以某型电机产品为例给出了应用实例。通过该模型的应用,可实现对牵引装备快速经济地维护保养,进一步提升了装备运用的可靠性,提高了维修效率,降低了全寿命周期成本。 展开更多
关键词 牵引装备 rcm 动态维修模式 预防性维修 趋势预测
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Migration and Pathological Journeys: A Case Report of 5 Patients at the National Hospital in Niamey
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作者 Ousseyni Zika Oumou Moussa Djibrilla +7 位作者 Ataigba Iréti Néthania Elie Salifou A. M. Mobarak Daou Mamane Nanéma Désiré Abdou Bakari Sangaré Ismaël Coulibaly Modibo Douma Maiga Djibo Ouédraogo Arouna 《Open Journal of Psychiatry》 2025年第1期24-34,共11页
This study aims to explore the unconscious motivations underlying migration in Niger, with an emphasis on understanding the phenomenon of pathological travel. Its aim is to identify the unconscious factors of patholog... This study aims to explore the unconscious motivations underlying migration in Niger, with an emphasis on understanding the phenomenon of pathological travel. Its aim is to identify the unconscious factors of pathological travel among migrants. Pathological travel, as discussed in the scientific literature on psychopathology, is characterised by movements initiated under the influence of delusions, hallucinations or other serious psychiatric disorders. The aim of this research is to contribute to our understanding of how these unconscious factors influence migration decisions. Using a retrospective analysis of five cases, this study examines the psychological and psychiatric dimensions of migration, particularly among patients referred to the psychiatry department of the Niamey National Hospital between 2017 and 2018. The five cases analysed, representing 12% of a cohort of 40 migrant patients, suffered from chronic psychotic disorders, including schizophrenia and chronic hallucinatory psychosis. By means of diagnostic interviews and categorical sorting, three main unconscious motivations were identified: the delusional state with themes of filiation and persecution, the hallucinations that dictated the travel behaviour, and the dissociative states manifested by depersonalisation and derealisation. It also emerges from this analysis that pathological travel often involves prolonged journeys on foot and without purpose. Thus, untreated mental illness plays a significant role in shaping and influencing individual and social behaviour. The results of this study have important implications for public health and migration policy. They highlight the need to integrate health assessments into migration management systems, particularly in regions serving as transit hubs for migrants. The research also highlights the need for culturally sensitive psychiatric interventions to address the interaction between pre-existing mental disorders and migration. This study contributes to a better understanding of the psychological dimensions of migration by highlighting the importance of addressing mental health as an integral part of humanitarian action. The knowledge gained paves the way for future research to explore this understudied aspect of migration on a broader scale. 展开更多
关键词 migration Mental Illness Pathological Journeys Unconscious Psychological Motivations NIGER
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基于RCM的轨道交通车辆均衡修优化方法
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作者 王伟 毛建鹏 +1 位作者 王钐森 陈学娇 《轨道交通装备与技术》 2025年第4期48-54,共7页
随着城市人口增多以及交通需求增大,城市轨道交通的交通运量与运力矛盾突出。为保证车辆的正点率和上线率满足交通需求,车辆的维修模式至关重要。基于以可靠性为中心的维修(RCM)分析故障数据,再根据熵权-模糊综合评价法评估风险等级,选... 随着城市人口增多以及交通需求增大,城市轨道交通的交通运量与运力矛盾突出。为保证车辆的正点率和上线率满足交通需求,车辆的维修模式至关重要。基于以可靠性为中心的维修(RCM)分析故障数据,再根据熵权-模糊综合评价法评估风险等级,选出需要均衡修的车辆关键系统部件。接着利用模块的划分重组以及模型的构建,优化部件结构在维修时的分配,最后通过退火算法进行计算。经过该方法优化,S地铁公司均衡修每年的库停时间将缩减为20 d,为国内轨道交通车辆关键部件的均衡修流程优化提供了参考。 展开更多
关键词 轨道交通车辆 均衡修流程 熵权-模糊综合评价法 rcm分析 模块重组 模拟退火算法
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Variation of migration routes in the central Asian-breeding Common Cuckoo population influenced by the Qinghai-Tibet Plateau
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作者 Zhichang Cheng Donghui Ma +3 位作者 Mengjie Lu Xingnan Du Lingwang Kong Xinkang Bao 《Avian Research》 2025年第3期441-449,共9页
Ecological barriers present significant challenges to bird migration by limiting the availability of stopover sites and shelters. The Qinghai-Tibet Plateau, a major migratory barrier located in higher latitude Central... Ecological barriers present significant challenges to bird migration by limiting the availability of stopover sites and shelters. The Qinghai-Tibet Plateau, a major migratory barrier located in higher latitude Central Asia, exerts a substantial influence on avian migration patterns. Species traversing such ecological barriers may adopt multiple optimal routes, which can contribute to the formation of migratory divides. From 2018 to 2021, the migration routes of 13 adult Common Cuckoos (Cuculus canorus) breeding in the north of the Qinghai-Tibet Plateau were tracked using satellite transmitters. We found Common Cuckoos have two primary migration routes: western and eastern, respectively following western and eastern edges of the Qinghai-Tibet plateau. The eastern and western routes are likely the optimal routes for the Central Asian Common Cuckoos population to navigate the Qinghai-Tibet Plateau. Furthermore, two individuals exhibited intermediate migration routes, suggesting attempted traverses of the Qinghai-Tibet Plateau, although neither completed the migration. These intermediate routes may indicate migratory behavior influenced by hybridization between eastern and western populations or migratory flexibility. Common Cuckoos exhibit significantly faster migration speed, flight speed, and shorter stopover durations during spring compared to autumn. The observed seasonal differences in migration behavior support birds following time-minimization strategies during spring migration. These results revealed the diverse migration routes of Common Cuckoos shaped by the Qinghai-Tibet Plateau and seasonal variation in migration patterns. 展开更多
关键词 Birds migration Cuculus canorus Migrant strategy migration routes Qinghai-Tibet plateau
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Assessment of seismic spatiotemporal characteristics and migration distance in the Badong section of the Three Gorges Reservoir Area
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作者 Guoyong Duan Fei Li +1 位作者 Kongwei Wang Yaobo Xu 《Earthquake Research Advances》 2025年第1期38-45,共8页
This paper aims to elucidate the seismic characteristics of the Three Gorges Reservoir area after impoundment and investigate the seismic source migration.Based on the seismic data analysis from the Badong segment in ... This paper aims to elucidate the seismic characteristics of the Three Gorges Reservoir area after impoundment and investigate the seismic source migration.Based on the seismic data analysis from the Badong segment in the Three Gorges Reservoir area,we assessed the local temporal and spatial variations in the frequent earthquakes.Correlation analysis was conducted to investigate the relationship between changes in reservoir water levels and the occurrence of reservoir-induced earthquakes.Additionally,we examined the regularity of earthquake occurrences at the exact location during different periods.Based on the fault mechanics principles,a formula was derived to estimate the length of open and wing-shaped rupture at the hypocenter under the influence of pore or excess pore water pressure.The results reveal that reservoir-induced seismicity demonstrates short-term cycles characterized by alternating"active periods"and"quiet periods,"as well as long-term cycles with the combined periods.The probability of earthquakes occurring within one year at the epicentre is relatively high and decreases after four years.The derived formula can be utilized to estimate the seismic migration distance at the epicentre in the short term.These research findings provide valuable insights for analyzing the regularity of reservoir-induced earthquake activities and understanding the mechanism of seismic source migration. 展开更多
关键词 Reservoir-induced earthquake Seismic migration Pore water pressure Earthquake source mechanism Earthquake migration distance
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Why the migration of peritoneal shunt catheter into the scrotum occurs more in children:A systematic literature review
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作者 Rajendra Kumar Ghritlaharey 《World Journal of Meta-Analysis》 2025年第2期6-26,共21页
BACKGROUND Ventriculoperitoneal shunt(VPS)catheter insertion is one of the most widely accepted surgical procedures for hydrocephalus.Migration of the end of the distal VPS catheter into the scrotum is one of the rare... BACKGROUND Ventriculoperitoneal shunt(VPS)catheter insertion is one of the most widely accepted surgical procedures for hydrocephalus.Migration of the end of the distal VPS catheter into the scrotum is one of the rare complications of VPS catheter insertion.METHODS This is a systematic review of the published cases,and the literature search was performed from 1974 to June 30,2024,to retrieve the relevant manuscripts.The cases were grouped into two.Group A included cases of migration of the distal VPS catheter into the scrotum,detected in children.Group B included the cases of migration of the distal VPS catheter into the scrotum,which was detected in adults and older people.RESULTS One hundred-twenty cases of migration of the distal end of VPS catheter into the scrotum were included in this study,a systematic literature review.Group A included n=112 cases,and group B included n=8 cases only.Three-fourths of the cases involved the right scrotum.Bilateral involvement was rare.The indication for initial VPS insertion was congenital hydrocephalus in four-fifths of the group A cases.The majority were infants at the time of initial shunt insertion.Four-fifths of the group A cases were 24 months-old or younger at the time of clinical diagnosis and treatment was provided for migration of the distal VPS catheter into the scrotum.In children,the interval from VPS insertion or shunt revision if any,to the diagnosis of the complication mentioned above was 12 months or less in four-fifths of the cases.The repositioning of migrated distal VPS catheter into the peritoneal cavity and herniotomy was preferred for the surgical procedure,and it was performed for two-thirds of group A cases.CONCLUSION Migration of the distal part of the VPS catheter into the scrotum is a rare complication of cerebrospinal fluid diversion via VPS catheter insertion.It was most frequent in children,and the right side of the scrotum was most often involved. 展开更多
关键词 INFANTS CHILDREN Complication HYDROCEPHALUS migration SCROTUM
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Historical Traces in the RCM Piano Score Archive: Evolution of Pedagogical Approaches Through Editions
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作者 Lin Sun 《Cultural and Religious Studies》 2025年第4期209-217,共9页
This meta-analysis examines 45 peer-reviewed studies(1950-2023)analysing 320 piano score editions from the Royal Conservatory of Music(RCM)Archive,employing robust statistical methods to quantify pedagogical evolution... This meta-analysis examines 45 peer-reviewed studies(1950-2023)analysing 320 piano score editions from the Royal Conservatory of Music(RCM)Archive,employing robust statistical methods to quantify pedagogical evolution.The data reveal a 42%increase in fingering density within post-2000 editions(Hedges’g=0.41,p<0.001,CI[0.28,0.54]),with Romantic works showing the highest variability(g=0.59 vs.Baroque g=0.12).Strong correlations emerged between editorial changes and pedagogical trends(r=0.67,p=0.002),particularly adopting ergonomic techniques post-1980.Performance data indicate modern editions improve advanced student outcomes by 12%(OR=1.12[1.05,1.19])but may overwhelm beginners(error rate+18%).The study establishes empirical evidence for three pedagogical epochs:technical rigor(pre-1980),transitional(1980-2000),and expressive flexibility(post-2000).These findings withstand publication bias tests(Egger’s t=1.2,p=0.24)and significantly affect curriculum design and historical performance practice. 展开更多
关键词 piano pedagogy editorial analysis quantitative musicology rcm Archive
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Enhanced immune responses of gregarious larvae contribute to successful adult migration in the migratory oriental armyworm
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作者 Hailong Kong Dong Guo +3 位作者 Lei Zhang Dianjie Xie Kenneth Wilson Xingfu Jiang 《Journal of Integrative Agriculture》 2025年第8期3141-3154,共14页
Migratory insect pests tend to suddenly immigrate into new habitats over a short period to simultaneously lay eggs in clusters,resulting in gregarious larvae that cause severe damage to crops.These aggregated larvae c... Migratory insect pests tend to suddenly immigrate into new habitats over a short period to simultaneously lay eggs in clusters,resulting in gregarious larvae that cause severe damage to crops.These aggregated larvae can adapt well to various natural enemies and pathogens in their new habitats,but how their resistance might be enhanced and its immunological significance remain unknown.Here,we examined how infection by a pathogen and a parasitic fly affect the immune response and migratory behavior in two phases of the oriental armyworm,Mythimna separata,which differ dramatically in their flight capacity and fecundity.The gregarious larvae displayed greater resistance than solitary larvae to the challenges of both the entomopathogenic fungus Metarhizium anisopliae and the parasitoid Exorista civilis.In response to a challenge by M.anisopliae,gregarious larvae exhibited more pronounced increases in phenoloxidase(PO)activity and lysozyme activity than solitary larvae.Furthermore,in addition to the greater PO and lysozyme activities,the levels of dopamine and 5-hydroxytryptamine(5-HT)were also greater in challenged gregarious and solitary larvae.Injection of dopamine(or 5-HT)significantly enhanced PO activity,lysozyme activity,antibacterial activity and larval survival.Subsequently,there was a significant increase in the flight capacity of adults derived from gregarious larvae challenged by M.anisopliae;while no significant variation was observed in the adults from challenged solitary larvae.The preoviposition period,oviposition period and fecundity were not significantly affected by M.anisopliae,regardless of whether the larvae were gregarious or solitary.These results provide new insights into the relationship between migration and immunity in insects,and their behavior after immunization. 展开更多
关键词 gregariousness immunity migration neurohormone Mythimna separata
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Deformation and migration characteristics of bubbles moving in gas-liquid countercurrent flow in annulus
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作者 YIN Bangtang DING Tianbao +4 位作者 WANG Shulong WANG Zhiyuan SUN Baojiang ZHANG Wei ZHANG Xuliang 《Petroleum Exploration and Development》 2025年第2期471-484,共14页
The gas-liquid countercurrent flow pattern is complex and the bubble migration velocity is difficult to predict in the process of bullheading well killing.The experiment on bubble migration in gas-liquid countercurren... The gas-liquid countercurrent flow pattern is complex and the bubble migration velocity is difficult to predict in the process of bullheading well killing.The experiment on bubble migration in gas-liquid countercurrent flow in annulus is carried out under different working conditions to reveal how the wellbore inclination angle,liquid phase property and countercurrent liquid velocity affect the bubble deformation and bubble migration trajectory/velocity,and to establish a bubble migration velocity prediction model.The bubbles in the countercurrent flow mainly migrate in two modes:free rising of isolated bubbles,and interactive rising of multiple bubbles.The bubbles migrate by an S-shaped trajectory in the countercurrent flow.With the increase of countercurrent liquid velocity,the lateral oscillation of bubbles is intensified.The increases of wellbore inclination angle,liquid density and liquid viscosity make the bubble migration trajectory gradually to be linear.The bubble is generally ellipsoidal during its rising.The wellbore inclination angle has little effect on the degree of bubble deformation.The bubbles are ellipsoidal during rising,with little influence of wellbore inclination angle on bubble deformation.With the increase of liquid viscosity and density,the aspect ratio of the bubble decreases.As the wellbore inclination angle increases,the bubble migration velocity gradually decreases.As the liquid viscosity increases,the bubble migration velocity decreases.As the liquid density increases,the bubble migration velocity increases slightly.The established bubble migration velocity prediction model yields errors within±15%,and demonstrates broad applicability across a wide range of operating conditions. 展开更多
关键词 bullheading well killing method gas-liquid countercurrent flow bubble aspect ratio bubble migration trajectory bubble migration velocity
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Stem cell-derived neural organoids as platforms to investigate glioblastoma invasion and migration:A systematic review
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作者 Arielly da Hora Alves Nicole Mastandrea Ennes do Valle +7 位作者 Bruno Yukio Yokota-Moreno Marta Caetano dos Santos Galanciak Keithy Felix da Silva Javier Bustamante Mamani Andrea Laurato Sertie Fernando Anselmo de Oliveira Mariana Penteado Nucci Lionel Fernel Gamarra 《World Journal of Stem Cells》 2025年第8期163-185,共23页
BACKGROUND Glioblastoma multiforme(GBM)is the most aggressive and prevalent primary malignant brain tumor in adults,marked by poor prognosis and high invasiveness.Traditional GBM invasion assays,such as those involvin... BACKGROUND Glioblastoma multiforme(GBM)is the most aggressive and prevalent primary malignant brain tumor in adults,marked by poor prognosis and high invasiveness.Traditional GBM invasion assays,such as those involving mouse brain xenografts,are often time-consuming and limited in efficiency.In this context,stem cell-derived neural organoids(NOs)have emerged as advanced,threedimensional,human-relevant platforms that mimic the cellular architecture and microenvironment of the human brain.These models provide novel opportunities to investigate glioblastoma stem cell invasion,a critical driver of tumor progression and therapeutic resistance.AIM To evaluate studies using stem cell-derived NOs to model glioblastoma migration/invasion,focusing on methodologies,applications and therapeutic implications.METHODS We conducted a systematic review following PRISMA guidelines,searching PubMed and Scopus for studies published between March 2019 and March 2025 that investigated NOs in the context of glioblastoma invasion/migration.After screening 377 articles based on predefined inclusion and exclusion criteria,10 original research articles were selected for analysis.Extracted data were categorized into four analytical domains:(1)Tumor model formation;(2)NO characteristics;(3)NO differentiation protocols;and(4)Invasion/migration assessment methodologies.RESULTS The included studies exhibit significant methodological heterogeneity GBM model development,particularly regarding model type,cell source and culture conditions.Most studies(70%)used suspension cell models,while 30%employed spheroids,with most research focusing on patient-derived glioblastoma stem cells.NOs were predominantly generated from human induced pluripotent stem cells using both guided and unguided differentiation protocols.Confocal fluorescence microscopy was the primary method used for assessing invasion,revealing invasion depths of up to 300μm.Organoid maturity and co-culture duration influenced results,while key factors for model optimization included tumor cell density,organoid age and extracellular matrix composition.Some studies also tested therapeutic strategies such as Zika virus and microRNA modulation.Collectively,findings support the utility of NOs as effective tools for studying GBM behavior and therapeutic responses in a humanized three-dimensional context.CONCLUSION Human NOs represent promising platforms for modeling glioblastoma invasion in a humanized three-dimensional environment.However,a limited number of studies and methodological heterogeneity hinder reproducibility.Protocol standardization is essential to enhance the translational application of these models. 展开更多
关键词 GLIOBLASTOMA Stem cell Organoid SPHEROID INVASION migration
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A high-efficiency Q-compensated pure-viscoacoustic reverse time migration for tilted transversely isotropic media
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作者 Qiang Mao Jian-Ping Huang +1 位作者 Xin-Ru Mu Yu-Jian Zhang 《Petroleum Science》 2025年第2期653-669,共17页
The attenuation and anisotropy characteristics of real earth media give rise to amplitude loss and phase dispersion during seismic wave propagation.To address these effects on seismic imaging,viscoacoustic anisotropic... The attenuation and anisotropy characteristics of real earth media give rise to amplitude loss and phase dispersion during seismic wave propagation.To address these effects on seismic imaging,viscoacoustic anisotropic wave equations expressed by the fractional Laplacian have been derived.However,the huge computational expense associated with multiple Fast Fourier transforms for solving these wave equations makes them unsuitable for industrial applications,especially in three dimensions.Therefore,we first derived a cost-effective pure-viscoacoustic wave equation expressed by the memory-variable in tilted transversely isotropic(TTI)media,based on the standard linear solid model.The newly derived wave equation featuring decoupled amplitude dissipation and phase dispersion terms,can be easily solved using the finite-difference method(FDM).Computational efficiency analyses demonstrate that wavefields simulated by our newly derived wave equation are more efficient compared to the previous pure-viscoacoustic TTI wave equations.The decoupling characteristics of the phase dispersion and amplitude dissipation of the proposed wave equation are illustrated in numerical tests.Additionally,we extend the newly derived wave equation to implement Q-compensated reverse time migration(RTM)in attenuating TTI media.Synthetic examples and field data test demonstrate that the proposed Qcompensated TTI RTM effectively migrate the effects of anisotropy and attenuation,providing highquality imaging results. 展开更多
关键词 ANISOTROPY ATTENUATION FD modeling Reverse-time migration
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Efficient numerical modeling scheme for solving fractional viscoacoustic wave equation in TTI media and its application in reverse time migration
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作者 Lei Xiang Jian-Ping Huang +5 位作者 Qiang Mao Xin-Ru Mu Fei Li Juan Chen Jin-Tao Liu Min Xu 《Petroleum Science》 2025年第7期2794-2817,共24页
Amplitude dissipation and phase dispersion occur when seismic waves propagate in attenuated anisotropic media,affecting the quality of migration imaging.To compensate and correct for these effects,the fractional Lapla... Amplitude dissipation and phase dispersion occur when seismic waves propagate in attenuated anisotropic media,affecting the quality of migration imaging.To compensate and correct for these effects,the fractional Laplacian pure viscoacoustic wave equation capable of producing stable and noise-free wavefields has been proposed and implemented in the Q-compensated reverse time migration(RTM).In addition,the second-order Taylor series expansion is usually adopted in the hybrid finite-difference/pseudo-spectral(HFDPS)strategy to solve spatially variable fractional Laplacian.However,during forward modeling and Q-compensated RTM,this HFDPS strategy requires 11 and 17 fast Fourier transforms(FFTs)per time step,respectively,leading to computational inefficiency.To improve computational efficiency,we introduce two high-efficiency HFDPS numerical modeling strategies based on asymptotic approximation and algebraic methods.Through the two strategies,the number of FFTs decreased from 11 to 6 and 5 per time step during forward modeling,respectively.Numerical examples demonstrate that wavefields simulated using the new numerical modeling strategies are accurate and highly efficient.Finally,these strategies are employed for implementing high-efficiency and stable Q-compensated RTM techniques in tilted transversely isotropic media,reducing the number of FFTs from 17 to 9 and 8 per time step,respectively,significantly improving computational efficiency.Synthetic data examples illustrate the effectiveness of the proposed Q-compensated RTM scheme in compensating amplitude dissipation and correcting phase distortion. 展开更多
关键词 ACOUSTIC ANISOTROPY ATTENUATION Reverse time migration
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基于RCM的轨道车辆检修规程优化分析研究
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作者 赵婷婷 万国强 +2 位作者 宋龙龙 刘克思 徐桂红 《设备管理与维修》 2025年第9期32-35,共4页
RCM分析是一种确定资产预防性维修需求、优化修程修制的系统工程方法。在轨道车辆检修规程开发过程中,通过RCM分析可以实现以最少的检修任务数量与最低的维修工作量覆盖所有可能的功能故障与故障影响。通过对RCM分析方法及决策流程开展... RCM分析是一种确定资产预防性维修需求、优化修程修制的系统工程方法。在轨道车辆检修规程开发过程中,通过RCM分析可以实现以最少的检修任务数量与最低的维修工作量覆盖所有可能的功能故障与故障影响。通过对RCM分析方法及决策流程开展研究,制定了MSI分析对象选取原则。通过可靠性数据处理分析与维修间隔计算,以某型动车组侧窗玻璃为例开展RCM分析,得出全生命周期维修检查任务与部件更换任务及其相应的维修间隔,实现了检修规程制定的可靠性经济性最优化,对于全生命周期管理具有十分重要的工程应用价值和理论意义。 展开更多
关键词 轨道车辆 全生命周期 rcm分析 修程优化
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Corrigendum to“Swan Project promotes citizen science initiative through a public bird migration tracking”[Avian Res.16(2025)100298]
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作者 Tetsuo Shimada Kan Konishi +2 位作者 Guozheng Li Guodong Shi Hiroyoshi Higuchi 《Avian Research》 2025年第4期846-846,共1页
The publisher regrets that the Appendix A.Supplementary data was not updated as per author and editor’s request.The publisher would like to apologise for any inconvenience caused.
关键词 bird migration TRACKING CORRIGENDUM citizen science
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机电设备维修中RCM技术的应用研究
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作者 张理国 《中国设备工程》 2025年第22期75-77,共3页
机电设备运行期间可能会出现多种故障,比如外部作用力所引发的故障;人员操作不当所引发的故障;环境原因所引发的故障等。而在机电设备故障维修过程中,RCM技术得到了广泛的应用。本文将探讨机电设备维修,分析RCM技术的应用,并提出一些应... 机电设备运行期间可能会出现多种故障,比如外部作用力所引发的故障;人员操作不当所引发的故障;环境原因所引发的故障等。而在机电设备故障维修过程中,RCM技术得到了广泛的应用。本文将探讨机电设备维修,分析RCM技术的应用,并提出一些应用建议,希望能解决RCM技术应用问题,达成机电设备维修要求。 展开更多
关键词 机电设备 设备维修 rcm技术
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