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哮喘患者血清lncRNA HOTTIP和RMRP水平表达及与气道重塑的相关性分析
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作者 郁芳芳 谢伟国 许群 《现代检验医学杂志》 2026年第1期70-74,85,共6页
目的探究哮喘患者血清长链非编码RNA(lncRNA)HOXA末端转录本反义RNA(HOTTIP)和线粒体RNA处理核糖核酸内切酶RNA组份(RMRP)表达变化及其与气道重塑的相关性。方法选取2022年1月~2024年6月江苏省江阴市人民医院呼吸与危重症医学科收治的... 目的探究哮喘患者血清长链非编码RNA(lncRNA)HOXA末端转录本反义RNA(HOTTIP)和线粒体RNA处理核糖核酸内切酶RNA组份(RMRP)表达变化及其与气道重塑的相关性。方法选取2022年1月~2024年6月江苏省江阴市人民医院呼吸与危重症医学科收治的急性发作期哮喘患者72例为急性发作期组,同期门诊随访哮喘缓解期患者70例为缓解期组,健康体检者142例为健康对照组。采用实时荧光定量聚合酶链反应(qRT-PCR)检测血清lncRNA HOTTIP和RMRP水平。采用多排螺旋CT测量患者肺内气道的内径(L)、外径(D),计算气道壁厚度与气道外径比值(T/D)和管壁面积占支气道总横截面积百分比(WA%)。采用肺功能检测仪检测第一秒用力呼气量(FEV1)、最高呼吸气流(PEF)水平。Spearman相关性分析哮喘患者血清lncRNA HOTTIP和RMRP水平与哮喘控制测试(ACT)评分的关系。Pearson相关性分析哮喘患者血清lncRNA HOTTIP和RMRP水平以及与肿瘤坏死因子-α(TNF-α)、γ干扰素(IFN-γ)、白细胞介素-18(IL-18)水平、气道重塑以及肺功能指标的关系。结果与健康对照组相比,急性发作期组和缓解期组IFN-γ水平显著降低(t=14.161,8.886),TNF-α、IL-18、lncRNA HOTTIP(1.32±0.15、1.15±0.15 vs 1.01±0.14)和RMRP(1.27±0.14、1.16±0.14 vs 1.02±0.13)水平显著升高(t=9.345~28.361);与缓解期组相比,急性发作期组ACT评分、IFN-γ水平显著降低(t=13.344,4.475),TNF-α、IL-18、lncRNA HOTTIP和RMRP水平显著升高(t=6.861~15.675),差异具有统计学意义(均P<0.05)。与健康对照组相比,急性发作期组和缓解期组FEV1、PEF水平显著降低(t=13.346~55.694),T/D、WA%水平显著升高(t=19.145~33.035);与缓解期组相比,急性发作期组FEV1、PEF水平显著降低(t=21.802、21.446),T/D、WA%水平显著升高(t=9.994、10.082),差异具有统计学意义(均P<0.05)。Spearman相关性分析显示哮喘患者血清lncRNA HOTTIP和RMRP水平与ACT评分呈负相关(r=-0.614、-0.399,均P<0.001)。Pearson相关性分析显示,哮喘患者血清lncRNA HOTTIP和RMRP水平呈正相关(r=0.625,P<0.05)。哮喘患者血清lncRNA HOTTIP和RMRP水平与TNF-α(r=0.658、0.632)、IL-18(r=0.584、0.586)、T/D(r=0.604、0.631)、WA%(r=0.597、0.588)水平呈正相关,与IFN-γ(r=-0.587、-0.517)、FEV1(r=-0.568、-0.577)、PEF(r=-0.634、-0.627)水平呈负相关(均P<0.05)。结论哮喘患者血清lncRNA HOTTIP和RMRP水平均呈高表达,与气道重塑和肺功能指标变化有关。 展开更多
关键词 哮喘 长链非编码核糖核酸HOXA末端转录本反义RNA 线粒体RNA处理核糖核酸内切酶RNA组份 气道重塑
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宫颈癌组织LncRNA HOTTIP表达及其与临床病理特征、生存预后的关系分析
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作者 马晓明 闫谨 马煜磊 《医学理论与实践》 2026年第1期26-30,47,共6页
目的:探讨宫颈癌组织长链非编码核糖核酸(LncRNA)同源异形盒A远端转录本(HOTTIP)表达及其与临床病理特征、生存预后的关系。方法:选取2019年2月—2023年4月我院145例宫颈癌患者为研究对象。收集手术切除的宫颈癌组织及癌旁组织,采用实... 目的:探讨宫颈癌组织长链非编码核糖核酸(LncRNA)同源异形盒A远端转录本(HOTTIP)表达及其与临床病理特征、生存预后的关系。方法:选取2019年2月—2023年4月我院145例宫颈癌患者为研究对象。收集手术切除的宫颈癌组织及癌旁组织,采用实时荧光定量聚合酶链反应(RT-qPCR)法检测LncRNA HOTTIP相对表达量并比较。比较不同临床病理特征患者癌组织LncRNA HOTTIP相对表达量。自出院当天持续随访至2024年4月或死亡,按照生存预后情况分为生存组、死亡组,比较2组临床资料,采用Cox回归法分析生存预后的影响因素,并进行Kaplan-Meier生存分析。结果:共脱落10例,最终纳入135例;宫颈癌组织LncRNA HOTTIP相对表达量高于癌旁组织(P<0.05);相较于病理类型鳞癌、国际妇产科联盟(FIGO)Ⅰ~Ⅱ期、肿瘤中/高分化、无神经侵犯及无脉管癌栓患者,病理类型非鳞癌、FIGOⅢ~Ⅳ期、肿瘤低/未分化、神经侵犯及脉管癌栓患者的癌组织LncRNA HOTTIP相对表达量升高(P<0.05);随访9~58个月,中位数39(20,46)个月,死亡率为38.52%(52/135);FIGOⅢ~Ⅳ期、肿瘤低/未分化、神经侵犯、脉管癌栓及癌组织LncRNA HOTTIP高表达是宫颈癌患者死亡的独立危险因素(P<0.05);Kaplan-Meier生存分析显示,FIGOⅢ~Ⅳ期、肿瘤低/未分化、神经侵犯、脉管癌栓及癌组织LncRNA HOTTIP高表达患者的生存率低于FIGOⅠ~Ⅱ期、肿瘤中/高分化、无神经侵犯、无脉管癌栓及癌组织LncRNA HOTTIP低表达患者(P<0.05)。结论:宫颈癌患者癌组织LncRNA HOTTIP相对表达量升高,癌组织LncRNA HOTTIP相对表达量不仅与病理类型、FIGO分期、肿瘤分化程度、神经侵犯及脉管癌栓密切相关,且为生存预后的影响因素。 展开更多
关键词 宫颈癌 长链非编码核糖核酸 同源异形盒A远端转录本 临床病理特征 生存预后
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基于教、学、评一体化的高中英语读后续写TIPS教学模式的建构与实践
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作者 徐长群 《教学月刊(中学版)(外语教学)》 2026年第1期72-78,共7页
读后续写是一种将阅读与写作紧密结合的考查形式,要求考生对所读材料进行续写,将其发展成一篇与给定材料有所衔接、情节架构自然,而且结构完整的短文。基于教、学、评一体化的高中英语读后续写TIPS教学模式有助于解决当前高中英语读后... 读后续写是一种将阅读与写作紧密结合的考查形式,要求考生对所读材料进行续写,将其发展成一篇与给定材料有所衔接、情节架构自然,而且结构完整的短文。基于教、学、评一体化的高中英语读后续写TIPS教学模式有助于解决当前高中英语读后续写教学存在的应试倾向严重、侧重指导学生堆砌华丽辞藻和套用写作套路、教师的评分较为主观等问题,其教学从量规驱动、情节共创、语言打磨、意义反思四个维度推进续作与阅读语篇的有机协同,有助于学生准确把握写作主题,创作出生动的情节,形成正确的价值观和良好的品格。 展开更多
关键词 读后续写 教、学、评一体化 tipS教学模式 高中英语
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肝硬化门静脉高压并发EVB患者TIPS术后死亡风险预测模型的构建与验证
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作者 杨小东 马志刚 +2 位作者 王旭 刘丽丽 冯鹏丽 《中国现代普通外科进展》 2025年第11期853-858,共6页
目的:探讨肝硬化门静脉高压并发食管胃底静脉曲张破裂出血(EVB)患者经颈静脉肝内门体分流术(TIPS)治疗后死亡的危险因素,并建立预测模型,为临床治疗提供参考依据。方法:回顾性分析2022年3月—2024年3月在保定市第二中心医院接受TIPS治疗... 目的:探讨肝硬化门静脉高压并发食管胃底静脉曲张破裂出血(EVB)患者经颈静脉肝内门体分流术(TIPS)治疗后死亡的危险因素,并建立预测模型,为临床治疗提供参考依据。方法:回顾性分析2022年3月—2024年3月在保定市第二中心医院接受TIPS治疗的80例肝硬化门静脉高压并发EVB患者的临床资料。根据28 d随访结果将患者分为存活组(n=65)和死亡组(n=15)。收集患者的一般资料、实验室检查、影像学特征、并发症情况及手术相关指标等数据。采用单因素分析筛选可能的危险因素,通过多元Logistic回归分析确定独立危险因素并构建预测模型。应用Hosmer-Lemeshow检验评估模型校准度,采用ROC曲线评估模型区分度。结果:单因素分析显示,两组在年龄、治疗时机、Child-pugh评分、MELD评分、血红蛋白、血小板计数、总胆红素、白蛋白、凝血酶原时间、出血量、门静脉血栓、肝性脑病、肝肾综合征等方面差异有统计学意义(P<0.05)。多元Logistic回归分析确定Child-pugh评分(OR=2.653,95%CI:1.672~4.207)、MELD评分(OR=1.924,95%CI:1.298~2.851)、出血量(OR=1.754,95%CI:1.235~2.489)、门静脉血栓(OR=3.247,95%CI:1.569~6.723)、肝性脑病(OR=2.834,95%CI:1.421~5.657)为肝硬化门静脉高压并发EVB患者TIPS治疗后死亡的独立危险因素(P<0.05)。预测模型的HosmerLemeshow检验提示模型具有良好的校准度(χ^(2)=6.234,P=0.621)。ROC曲线分析显示,模型的AUC为0.873(95%CI:0.773~0.939),敏感度为83.3%,特异度为87.7%。结论:Child-pugh评分、MELD评分、出血量、门静脉血栓及肝性脑病是肝硬化门静脉高压并发EVB患者TIPS治疗后死亡的独立危险因素。本研究建立的预测模型具有良好的预测效能,可为临床评估患者预后及制定个体化治疗方案提供参考。 展开更多
关键词 肝硬化 门静脉高压 食管胃底静脉曲张破裂出血 介入治疗 危险因素 预测模型
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美国国家科学基金会科技、创新与伙伴关系部(TIP)的组织角色、核心职能与运行机制 被引量:2
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作者 王正青 张竞文 《科技管理研究》 2025年第3期41-47,共7页
美国国家科学基金会于2022年成立的科技、创新与伙伴关系部(TIP),是以加速关键技术研发、培养创新人才为专职的机构。以TIP成立以来所发布的文献报告和活动资料为依据,分析TIP的组织架构、核心职能与运行机制,为中国构建更有效的科技成... 美国国家科学基金会于2022年成立的科技、创新与伙伴关系部(TIP),是以加速关键技术研发、培养创新人才为专职的机构。以TIP成立以来所发布的文献报告和活动资料为依据,分析TIP的组织架构、核心职能与运行机制,为中国构建更有效的科技成果转化机制提供参考借鉴。总体而言,TIP角色定位基于美国国家科学基金会的使命与战略目标,是对美国《2030年愿景》的落实,以高效联结为核心理念鼓励多样化研究。助力科技创新人才培养、参与科技创新系统建设和搭建科技成果转化平台是其三大核心职能,现已形成涵盖目标引领、主体协同、工作推进、持续发展和评价反馈的闭环式运行机制,助力建设科技转化新生态。TIP通过系列项目资助培养专业化研究人员,并通过发布创新可视化地图等途径,助力美国科技创新人才培养与成果转化。有鉴于此,为进一步完善中国科技成果转化的机制,政府有关部门应加强顶层设计,牵头建立可视化动态监测模型,促进数据和信息的开放获取,推动跨部门、跨专业交流。 展开更多
关键词 科技、创新与伙伴关系部 美国科学基金会 科技成果转化 科技人才培养 技术研发
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Tip-enhanced Raman scattering of glucose molecules 被引量:3
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作者 Zhonglin Xie Chao Meng +3 位作者 Donghua Yue Lei Xu Ting Mei Wending Zhang 《Opto-Electronic Science》 2025年第5期2-9,共8页
Glucose molecules are of great significance being one of the most important molecules in metabolic chain.However,due to the small Raman scattering cross-section and weak/non-adsorption on bare metals,accurately obtain... Glucose molecules are of great significance being one of the most important molecules in metabolic chain.However,due to the small Raman scattering cross-section and weak/non-adsorption on bare metals,accurately obtaining their"fingerprint information"remains a huge obstacle.Herein,we developed a tip-enhanced Raman scattering(TERS)technique to address this challenge.Adopting an optical fiber radial vector mode internally illuminates the plasmonic fiber tip to effectively suppress the background noise while generating a strong electric-field enhanced tip hotspot.Furthermore,the tip hotspot approaching the glucose molecules was manipulated via the shear-force feedback to provide more freedom for selecting substrates.Consequently,our TERS technique achieves the visualization of all Raman modes of glucose molecules within spectral window of 400-3200 cm^(-1),which is not achievable through the far-field/surface-enhanced Raman,or the existing TERS techniques.Our TERS technique offers a powerful tool for accurately identifying Raman scattering of molecules,paving the way for biomolecular analysis. 展开更多
关键词 tip-enhanced Raman scattering scanning near-field optical microscope fiber vector light field tip nanofocusing light source
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Locally Enhanced Flow and Electric Fields Through a Tip Effect for Efficient Flow‑Electrode Capacitive Deionization
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作者 Ziquan Wang Xiangfeng Chen +5 位作者 Yuan Zhang Jie Ma Zhiqun Lin Amor Abdelkader Maria‑Magdalena Titirici Libo Deng 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期1-17,共17页
Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer... Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of waters.However,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current collectors.Herein,a new tip-array current collector(designated as T-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport significantly.The effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal resistance.With the voltage increased from 1.0 to 1.5 and 2.0 V,the T-CC-based FCDI system(T-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current collectors.Meanwhile,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for T-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current collectors.Additionally,a salt removal efficiency of 99.89%was achieved with T-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability. 展开更多
关键词 Flow-electrode Capacitive deionization Current collector tip effect DESALINATION
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核心素养视角下运用数字资源构建TIPS集体备课模式的策略探究
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作者 张栋 梁治华 《求知导刊》 2025年第20期26-28,共3页
以发展学生核心素养为基本目标,着重探讨了TIPS集体备课模式的概念、应用价值和构建策略。教育部门和学校应通力合作,积极整合数字资源,重构备课流程,创新备课方式,推进动态评价,以确保数字化集体备课取得积极成果。
关键词 核心素养 tipS集体备课模式 数字资源 教学能力
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尿道板与龟头直径对TIP术治疗尿道下裂的影响研究
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作者 谢方达 赵野 +2 位作者 王贺 王春欢 林昊 《中文科技期刊数据库(文摘版)医药卫生》 2025年第9期057-060,共4页
为确定尿道板纵切卷管成形术(TIP)术治疗尿道下裂效果的影响因素,深入探究不同尿道板与龟头直径的比值的预后差异。方法 选取尿道下裂患儿40例。根据不同手术方式分为参照组(20例),尿道板/龟头直径比值<0.35;试验组(20例),尿道板/龟... 为确定尿道板纵切卷管成形术(TIP)术治疗尿道下裂效果的影响因素,深入探究不同尿道板与龟头直径的比值的预后差异。方法 选取尿道下裂患儿40例。根据不同手术方式分为参照组(20例),尿道板/龟头直径比值<0.35;试验组(20例),尿道板/龟头直径比值≥0.35。两组均采用TIP手术方法治疗,对患者术后进行随访。比较不同小组的术后并发症发生情况、手术成功率、术后膀胱功能及阴茎外观评分。结果 尿道板/龟头直径≥0.35的情况下,患儿的各项临床指标恢复更为优异,体现在试验组患儿手术相关指标、满意度、术后疼痛程度、膀胱功能、并发症结果均比参照组理想方面,P<0.05。结论 在尿道板/龟头直径≥0.35情况时,予以尿道下裂儿童开展TIP手术干预,可获取更为理想的结果。在该比例之下,患儿手术相关指标更为优异,并且术后疼痛感较轻,发生相关并发症的风险较低。 展开更多
关键词 尿道下裂 尿道板与龟头直径 tip 并发症
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温度对超级奥氏体不锈钢254SMO双面双弧TIPTIG焊接头点蚀行为的影响 被引量:1
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作者 郎泽宇 王璐璐 《电焊机》 2025年第1期9-18,共10页
双面双弧TIPTIG焊是一种可以有效降低焊接热输入的焊接方法,采用双面双弧TIPTIG焊对4 mm厚的254SMO超级奥氏体不锈钢板进行焊接,并系统研究了温度对其点蚀行为的影响。通过动电位极化、循环极化、Mott-Schottky和EIS等电化学测试,并结... 双面双弧TIPTIG焊是一种可以有效降低焊接热输入的焊接方法,采用双面双弧TIPTIG焊对4 mm厚的254SMO超级奥氏体不锈钢板进行焊接,并系统研究了温度对其点蚀行为的影响。通过动电位极化、循环极化、Mott-Schottky和EIS等电化学测试,并结合腐蚀形貌观察,发现254SMO接头的母材区、过渡区和焊缝区均发生了点蚀,其中过渡区点蚀最严重。随着温度的升高,接头的耐蚀性逐渐下降,临界点蚀温度在40~45℃之间。在不同的温度下,接头的耐点蚀性能与母材相近,达到工程中使用标准。接头和母材钝化机制相同,钝化膜均表现出n-p型半导体特征。但当温度高于45℃时,254SMO接头表面膜的稳定性略低于母材。 展开更多
关键词 双面双弧同步tipTIG焊 254SMO超级奥氏体不锈钢 温度 点蚀 钝化膜
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某纯电汽车Tip in抖动分析及优化
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作者 李玉凡 肖雨轩 +2 位作者 王凯新 张桂朋 王刚 《汽车科技》 2025年第4期37-41,共5页
随着电动汽车市场的快速发展,消费者对驾驶体验的要求提高,但起步时的冲击和抖动影响了舒适性和安全性。本文对某车企的二级减速纯电驱动系统,通过实车测试与仿真发现电机穿零冲击控制及传动系统侧隙是抖动主因。全因子分析显示,扭矩斜... 随着电动汽车市场的快速发展,消费者对驾驶体验的要求提高,但起步时的冲击和抖动影响了舒适性和安全性。本文对某车企的二级减速纯电驱动系统,通过实车测试与仿真发现电机穿零冲击控制及传动系统侧隙是抖动主因。全因子分析显示,扭矩斜率对冲击度影响最大。采用遗传算法优化后,延长扭矩变化时间(从0.05秒增至0.199秒),可降低冲击度72.8%。本文提出两种方案:一是调整扭矩变化时间;二是同时优化扭矩斜率时间和侧隙,这些方案在改善起步抖动方面具有重要工程应用价值。 展开更多
关键词 tip in 抖动 扭振 遗传算法
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Nasal Tip-Columella Subunits Infrastructural Reconstruction: 10th Rib Cartilage Graft Operative Technique
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作者 Wenbo Huang Takkun Chow +1 位作者 Sikkuen Chow Yangliu Liao 《International Journal of Otolaryngology and Head & Neck Surgery》 2025年第1期47-56,共10页
Background: Reconstruction of Nasal Tip Columella (NTC) subunits is one of the most challenging aspects in functional aesthetic rhinoplasty. Moreover, racial variation for Asian nose rhinoplasty could even demand soph... Background: Reconstruction of Nasal Tip Columella (NTC) subunits is one of the most challenging aspects in functional aesthetic rhinoplasty. Moreover, racial variation for Asian nose rhinoplasty could even demand sophistication of tip and columella strut graft infrastructure enhancement. Various autogenous graft options such as 6th costal cartilage, septal cartilage and conchal cartilage are very commonly considered whilst the 10th costal cartilage is scarcely reported. Objective and Method: The purpose of this manuscript is to illustrate the detailed operative steps to harvest the 10th costal cartilage for infrastructural grafting at NTC subunits by a case illustration. The pros and cons of different cartilage options will be discussed, particularly its application in cleft nose rhinoplasty in Chinese patient. We have adopted the 10th rib as the key option for NTC reconstruction in 11 cases of Chinese cleft secondary rhinoplasty since 2019 and have achieved good and stable results without complications. Conclusion: The 10th costal cartilage is one of the best options in Nasal Tip Columella subunits reconstruction, particularly in complex cleft nose or failure revision aesthetic rhinoplasty cases, due to its safety of harvesting, and the sufficient quality and quantity of grafting materials it provides for simultaneous adjunctive augmentation purpose. 展开更多
关键词 Nasal tip Columella Rhinoplasty 10th Rib Cartilage CLEFT Chinese
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Climatic and edaphic controls of root-tip production and mortality in five temperate tree species
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作者 Yaoyuan Ma Ni Yang +3 位作者 Siyuan Wang Changfu Huo Lizhong Yu Jiacun Gu 《Journal of Forestry Research》 2025年第1期127-138,共12页
Root tips are the main components of absorptive fine roots,but their seasonal dynamics and relationship to environmental factors remain unclear due to the difficulties in methodology.In this study,we explored the temp... Root tips are the main components of absorptive fine roots,but their seasonal dynamics and relationship to environmental factors remain unclear due to the difficulties in methodology.In this study,we explored the temporal patterns of root-tip production and mortality in monoculture plantations of five temperate tree species at a common site in northeastern China,and identified the general environmental controls on such processes.We made monthly in-situ assessments of root tip length(RTL)production and mortality in two hardwood and three coniferous species with a minirhizotron(MR)method during the growing seasons of 2008 and 2009.Air temperature,rainfall,soil temperature and water content at 10 cm depth were determined concurrently.RTL production in all species exhibited consistent peaks in summer(June–August)in two growing seasons.RTL mortality showed substantial interannual and interspecific variability,with peaks in autumn and winter in 2008,but various patterns in 2009.RTL production positively correlated with monthly soil and air temperature across all species,and with monthly rainfall in three coniferous species.However,there was no significant correlation between RTL production and soil water content.By contrast,RTL mortality was weakly related to environmental factors,showing positive correlations with soil temperature in Korean spruce,and with rainfall in Korean pine and Korean spruce.Our findings suggest that the seasonal patterns of RTL production are convergent across the five temperate tree species due to the overlapped distribution of heat and rainfall,which can conduce roots to maximizing the acquisition of nutrient resources in the soil. 展开更多
关键词 Root tips Seasonal dynamics PRODUCTION MORTALITY MINIRHIZOTRON Temperate forest
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超超临界机组G115耐热钢管TIP TIG接头组织与性能研究
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作者 盛美芳 刘鹏 +1 位作者 郭新芳 杨刘波 《电焊机》 2025年第6期155-162,共8页
采用TIG打底+TIPTIG焊对电站锅炉φ530 mm×115 mm的G115钢管进行连接,并进行770℃高温回火热处理,利用金相、硬度、冲击及电化学腐蚀等试验手段对接头显微组织与力学性能进行分析。研究表明,焊缝区主要由马氏体及少量铁素体组成,... 采用TIG打底+TIPTIG焊对电站锅炉φ530 mm×115 mm的G115钢管进行连接,并进行770℃高温回火热处理,利用金相、硬度、冲击及电化学腐蚀等试验手段对接头显微组织与力学性能进行分析。研究表明,焊缝区主要由马氏体及少量铁素体组成,组织以等轴晶和柱状晶为主;热影响区以板条马氏体及部分原奥氏体组织为主;母材呈现针片状马氏体形态。接头硬度呈现先下降后升高的趋势,母材处最低(210.5 HV0.2),热影响区略高于母材区,熔合区硬度先降低再逐渐升高,焊缝区硬度最高约为281.3 HV0.2。冲击韧性则表现出相反趋势,热影响区冲击吸收功达103.09 J,显著优于焊缝区的59.37 J,但两者均满足工程要求。电化学腐蚀试验揭示母材耐腐蚀性最优,焊缝区因高硬度马氏体组织导致耐蚀性下降。研究表明,TIPTIG焊接工艺可实现G115耐热钢管的高质量连接,但焊缝区高硬度与低韧性特征需通过工艺优化(如热输入调控或合金成分设计)进一步改善,以提升接头综合服役性能。 展开更多
关键词 G115耐热钢管 tipTIG焊 显微组织 力学性能 腐蚀
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Direct Writing Nanostructures on Au Nano-Film by Laser Irradiating Cantilevered Scanning Near-Field Optical Microscope Tip
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作者 Xuewen Wang Xuesong Mei +3 位作者 Hailong Yin Zhijun Wang Xiaoqiao He Jianlei Cui 《Engineering》 2025年第6期104-112,共9页
The fabrication of nanostructures beyond the diffraction limit has been the focus of nanotechnology research.Scanning probe microscopy(SPM)has attracted the attention of researchers for the detection and manufacture o... The fabrication of nanostructures beyond the diffraction limit has been the focus of nanotechnology research.Scanning probe microscopy(SPM)has attracted the attention of researchers for the detection and manufacture of nanostructures.Here,a nanosecond laser irradiated a cantilevered scanning nearfield optical microscopy(SNOM)tip and directly wrote subwavelength nanostructures on Au nano-film,without the assistance of a mask or vacuum atmosphere.This method was stable and reproducible for long-term use.The in situ morphology detection was conducted after the writing process by atomic force microscope(AFM).A feature linewidth of approximately 83.6 nm(<k/6)was confirmed using scanning electron microscopy(SEM).Linewidth of(167.8±6.6)nm was reproduced stably.Theoretical calculations revealed that the elliptical heat distribution under the SNOM tip generated different linewidths when the tip scanned vertically and horizontally.It also interpreted the influential mechanism of single-pulse energy.The simulated linewidths were consistent with the fabricated linewidths.According to the elemental analysis by energy dispersive spectrometer(EDS),the mechanism of this method can be interpreted asmelting of the Au nano-film instead of oxidation.Owing to its high positioning,machining accuracy,and instantaneous energy,this technology is considered convenient and economical for nanostructure fabrication and is proposed to be applied in nanolithography on multiple materials in the future. 展开更多
关键词 Laser direct writing NANOLITHOGRAPHY Cantilevered SNOM tip Near-field manufacturing
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On the subspace selection and frequency identification of rotor blade vibration signal measured by blade tip timing
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作者 Zengkun WANG Zhibo YANG +3 位作者 Baijie QIAO Min YE Hao ZUO Baoqing DING 《Chinese Journal of Aeronautics》 2025年第7期273-284,共12页
Anti-aliasing spectrum analysis is essential for rotor blade condition monitoring based on Blade Tip Timing(BTT).The Multiple Signal Classification(MUSIC)algorithm,which exploits the orthogonality between signal and n... Anti-aliasing spectrum analysis is essential for rotor blade condition monitoring based on Blade Tip Timing(BTT).The Multiple Signal Classification(MUSIC)algorithm,which exploits the orthogonality between signal and noise subspaces,has been successfully applied for this purpose.However,conventional subspace selection methods relying on fixed thresholds are sensitive to variations in large eigenvalues.Furthermore,the complex disturbances during rotor operation and measurement complicate the identification of blade vibration characteristics.To overcome these challenges,this paper proposes Adaptive Subspace Separation(ASS)and Local Spectral Centroid(LSC)methods to improve the adaptability of subspace selection and the stability of frequency identification,respectively.The impacts of overestimating and underestimating the subspace dimensions on MUSIC's performance are derived mathematically.Simulation and experiments demonstrate the effectiveness of proposed approaches:ASS offers more accurate and stable subspace dimension selection and tracking,while LSC reduces the standard deviation of estimated frequencies by 30 percent. 展开更多
关键词 Blade tip timing Rotor blade Signal subspace Spectrum analysis MUSIC
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肝脏“搭桥术”TIPS的前世今生
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作者 张信哲 贺娜 《肝博士》 2025年第3期31-32,共2页
疏浚河道、搭桥通航,自古以来都是疏通水运,繁荣经济的重要举措。门静脉系是人体最大的、收集腹腔内不成对脏器(如脾、胰、肠等)血液回流的主干道,当它的血液回流受阻,如常见的肝硬化导致门脉系血液回流受阻,便会发生类似河道壅塞的情... 疏浚河道、搭桥通航,自古以来都是疏通水运,繁荣经济的重要举措。门静脉系是人体最大的、收集腹腔内不成对脏器(如脾、胰、肠等)血液回流的主干道,当它的血液回流受阻,如常见的肝硬化导致门脉系血液回流受阻,便会发生类似河道壅塞的情况。能否在堵塞的门静脉与体循环系统之间。 展开更多
关键词 肝脏搭桥术 tipS 肝硬化 血液回流 门静脉系
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多模态影像融合技术在TIPS介入治疗中的研究及应用进展
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作者 谭文乐 吴敬玺 +1 位作者 李晓辉 段峰 《手术电子杂志》 2025年第4期1-5,共5页
多模态影像融合技术在介入治疗领域的应用日益受到重视,尤其是在经颈静脉肝内门体分流术(TIPS)中,该技术能够显著提升治疗的安全性和有效性。当前,TIPS介入治疗面临着术前评估不充分、术中导航不精准及术后监测不足等问题,这些问题直接... 多模态影像融合技术在介入治疗领域的应用日益受到重视,尤其是在经颈静脉肝内门体分流术(TIPS)中,该技术能够显著提升治疗的安全性和有效性。当前,TIPS介入治疗面临着术前评估不充分、术中导航不精准及术后监测不足等问题,这些问题直接影响了治疗效果和患者预后。研究表明多模态影像融合技术通过整合不同影像学方法的数据,能够为医师提供更全面的信息,改善术前规划,优化术中操作,增强术后评估的准确性。本文综述了多模态影像融合技术在TIPS介入治疗中的研究进展,重点探讨其在术前评估、术中导航及术后监测中的具体应用,同时分析了不同影像技术的优势与局限性。最后,展望了该领域未来的发展方向,以期推动临床实践的发展和提升患者的治疗效果。 展开更多
关键词 多模态影像融合技术 tipS 介入治疗 影像学 应用进展
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A novel rotor dynamic balancing method based on blade tip clearance measurement without the once per revolution sensor
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作者 Weibo LI Weimin WANG +3 位作者 Shuai ZHANG Jiale WANG Yulong LIN Tianqing LI 《Chinese Journal of Aeronautics》 2025年第2期445-458,共14页
The existence of the aeroengine casing,limited monitoring points,and multi-fault characteristics make obtaining the rotor’s vibration transmission characteristics challenging,resulting in difficulties accurately iden... The existence of the aeroengine casing,limited monitoring points,and multi-fault characteristics make obtaining the rotor’s vibration transmission characteristics challenging,resulting in difficulties accurately identifying the rotor unbalance.This paper utilizes a high-frequency composite sensor to monitor the engine’s blade tip clearance(BTC)and extracts unbalanced information from BTC signals for rotor dynamic balancing,while avoiding the need for the once per revolution(OPR)sensor.First,the vibration characteristics of the rotor-blade system under multi-fault conditions are investigated.Then,based on BTC measurement,a none OPR method and an unbalance identification method are proposed,in which the radial vibration of the blade tip in the BTC signals at different speeds is extracted and operated in the time domain to obtain the rotor unbalanced vibration,the signal is reconstructed,and cross-correlation analysis is used to accurately identify the magnitude and phase of the unbalanced signal.Finally,a rotor test bench is utilized for experimental verification.The results reveal that the dynamic balancing method based on the BTC signal can more precisely identify the rotor unbalance than the traditional rotor dynamic balancing method.The application of this technique will effectively improve engine health management and fault prediction. 展开更多
关键词 AEROENGINE Rotor unbalance Composite sensor None once per revolution Blade tip clearance Dynamic balancing
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Dome vs tapered tip sphincterotomes in endoscopic retrograde cholangiopancreatography:A pilot study on cannulation success and postprocedural pancreatitis
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作者 Jungnam Lee Jin-Seok Park 《World Journal of Gastrointestinal Surgery》 2025年第5期229-238,共10页
BACKGROUND Despite advancements,endoscopic retrograde cholangiopancreatography(ERCP)poses challenges,including the risk of post-ERCP pancreatitis and difficulty of biliary cannulation.AIM To compare dome and tapered t... BACKGROUND Despite advancements,endoscopic retrograde cholangiopancreatography(ERCP)poses challenges,including the risk of post-ERCP pancreatitis and difficulty of biliary cannulation.AIM To compare dome and tapered tip sphincterotomes,focusing on their efficacy in achieving successful biliary cannulation and reducing the incidence of post-ERCP pancreatitis.METHODS In this prospective,single-blind,randomized pilot study conducted at Inha Uni-versity Hospital,85 patients undergoing ERCP were equally divided into dome and tapered tip sphincterotome groups.The co-primary outcomes were the success rate of selective biliary cannulation and incidence of post-ERCP pancre-atitis.The secondary outcomes included biliary cannulation time,number of unintended pancreatic duct access events,and total procedure time.RESULTS The success rates of selective biliary cannulation were 74.4%and 85.7%in the dome and tapered tip groups,respectively,with no significant difference(P=0.20).Similarly,the incidence of post-ERCP pancreatitis did not differ significantly between the groups(5 cases in the tapered tip group vs 6 in the dome tip group,P=0.72).However,difficult cannulation was significantly more common in the dome tip group than in the tapered tip group(P=0.05).Selective biliary cannula-tion time emerged as a significant predictor of post-ERCP pancreatitis(multivariate odds ratio=9.33,95%confi-dence interval:1.31-66.44,P=0.03).CONCLUSION This study indicated that the sphincterotome tip type does not markedly affect biliary cannulation success or post-ERCP pancreatitis rates.However,cannulation duration is a key risk factor for post-ERCP pancreatitis.These findings provide preliminary insights that highlight the importance of refining ERCP practices,including sphinc-terotome selection,while underscoring the need for larger multicenter studies to improve procedure time and patient safety. 展开更多
关键词 Endoscopic retrograde cholangiopancreatography Post-endoscopic retrograde cholangiopancreatography pancrea-titis Selective biliary cannulation Sphincterotome tip configuration PANCREATITIS
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