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乒乓球运动者正手弧圈球不同触地模式的下肢生物力学变化

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中国组织工程研究 2025年第14期29卷 2995-3001页

作者：晋鹏飞任杰上海体育大学中国乒乓球学院上海市200438

背景:探讨基于步法的足部触地模式对乒乓球运动中下肢关节运动特征的影响,可为指导下肢训练提供科学依据。目的:对比乒乓球运动中不同触地模式下的运动学和动力学差异。方法:使用动作捕捉和三维测力台同步采集17名专业乒乓球运动员在正... 详细信息

背景:探讨基于步法的足部触地模式对乒乓球运动中下肢关节运动特征的影响,可为指导下肢训练提供科学依据。目的:对比乒乓球运动中不同触地模式下的运动学和动力学差异。方法:使用动作捕捉和三维测力台同步采集17名专业乒乓球运动员在正常触地和全脚掌触地模式下优势侧下肢的运动学和动力学数据。配对样本t检验用于分析关节角度、地面反作用力、关节反作用力和关节力矩等离散指标的统计学差异;统计参数映射用于分析足底压力中心移动轨迹和膝关节力矩等时间序列数据的统计学差异。结果与结论:①正常触地模式下的膝关节内翻、侧向地面反作用力、膝关节垂直反作用力和伸膝力矩峰值显著高于全脚掌触地模式;②在足底压力中心移动距离中的89%-91%运动阶段,正常触地模式压力中心显著远于全脚掌触地模式;③在X轴力矩曲线中的23%-38%运动阶段,正常触地模式的伸膝力矩显著大于全脚掌触地模式;④在Y轴力矩曲线的8%-18%运动阶段,全脚掌触地模式显著大于正常触地模式。通过对比不同触地模式的下肢生物力学特征值和统计参数映射分析结果,认为全脚掌触地模式可能是影响乒乓球运动表现的重要因素。乒乓球运动中需要针对性地对触地模式进行调整和练习,避免使用全脚掌触地模式,提升乒乓球运动者下肢运动能力。

关键词：触地模式乒乓球运动学动力学运动表现

Floquet analysis of fundamental,subharmonic and detuned secondary instabilities of Grtler vortices

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Science China(Physics,Mechanics & Astronomy) 2014年第3期57卷 555-561页

作者： ren jie FU song School of Aerospace Engineering Tsinghua University

Nonlinear parabolized stability equations are employed in this work to investigate the nonlinear development of the G6rtler insta- bility up to the saturation stage. The perturbed boundary layer is highly inflectional both in the normalwise and spanwise directions and receptive to the secondary instabilities. The Floquet theory is applied to solve the fundamental, subharmonic and detuned secondary instabilities. With the Gortler-vortices-distorted base flow, two classes of secondary disturbances, i.e. odd modes and even modes, are identified according to the eigenfunctions of the disturbances. These modes may result in different patterns in the late stages of the transition process. Li and Malik [ 1 ] have shown the sinuous and varicose types of breakdown originating from the odd and even modes. The current study focuses on the four most amplified modes termed the even modes I ＆ Ⅱ and odd modes I ＆ lI. Odd mode II was missing in the work of Li and Malik [1] probably due to their inviscid simplifeation. The detuned modes are confirmed to be less amplifed than the fundamental （for the odd mode I） and subharmonic modes （for even modes I ＆ II and the odd mode II）.

关键词： Goirtler vortices secondary instability Floquet theory

Competition of the multiple Grtler modes in hypersonic boundary layer flows

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Science China(Physics,Mechanics & Astronomy) 2014年第6期57卷 1178-1193页

作者： ren jie FU song School of Aerospace Engineering Tsinghua University

Competition of multiple Gortler modes in hypersonic boundary layer flows are investigated with the local and marching methods. The wall-layer mode （mode W） and the trapped-layer mode （mode T） both occur in the compressible boundary layer where there exists a temperature adjustment layer near the upper edge. The mode T has the largest growth rate at a lower Gortler number while the mode W dominates at larger G/Srtler numbers. These two modes are both responsible for the flow transition in the hypersonic flows especially when Gortler number is in the high value range in which the crossover of these two modes takes place. Such high Gortler numbers are virtually far beyond the neutral regime. The nonparallel base flows, therefore, cease to influence the stability behavior of the Gortler modes. The effects of the Mach number on the multiple Gortler modes are studied within a chosen Mach number of 0.95, 2, 4 and 6. When the flow Mach number is sufficiently large, e.g., Ma ≥4, the growth rate crossover of the mode T and mode W occurs both in the conventional G-β map as well as on the route downstream for a fixed wavelength disturbance. Four particular regions （Region T, T-W, W-T and W） around the crossover point are highlighted with the marching analysis and the result matches that of the local analysis. The initial disturbance of a normal mode maintains the shape in its corresponding dominating region while a shape-transformation occurs outside this region.

关键词： Gortler vortices linear stability theory multiple modes local analysis marching analysis

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流动注射分析原理及进展

天津化工 2003年第2期17卷 22-25页

作者：任杰宋海华天津大学化工学院天津300072

本文扼要说明了流动注射分析技术 (FIA)的基本原理、仪器组成和特点。对国外流动注射分析系统的发展现状作了简要介绍。

关键词：流动注射分析顺序注射微珠注射阀上实验室

Pulp health and calcific healing of a complicated crown–root fracture with additional root fracture in a maxillary incisor: A case report

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World Journal of Clinical Cases 2025年第3期13卷 42-49页

作者： Na Li Yue-Yue ren Ying Tang Qi Yang Tian-Tian Meng song Li Jing Zhang Stomatological Hospital and College Anhui Medical UniversityHefei 230032Anhui ProvinceChina Department of Endodontics The Affiliated Stomatological Hospital of Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina

BACKGROUND Complicated crown–root fracture (CRF) involves severe injury to the crown, root,and pulp, and may be accompanied by multiple root fractures. The loss of a toothhas lifelong consequences for children and teenagers, but the maintenance of pulphealth and the calcific healing of multiple root fractures are rarely reported in *** SUMMARY This case reports healing of a permanent tooth with complicated crown–root andadditional root fractures, in which pulp health was maintained. A 10-year-old girlfell and fractured the root of her maxillary left central incisor at the cervical *** the coronal fragment was repositioned, the tooth was splinted until thetooth was no longer mobile, 2 years later. Eight years after treatment, the toothhas remained asymptomatic with vital pulp and localized gingival ***-beam computed tomography revealed not only calcified healing of the CRFbut also spontaneous healing in an additional undiagnosed root fracture. Thefracture line on the enamel could not be healed by hard tissue and formed agroove in the cervical crown. It was speculated that the groove was related to thelocalized gingival *** This case provides a clinical perspective of the treatment of a tooth with acomplicated CRF and an additional root fracture.

关键词： Complicated crown-root fracture Multiple root fracture Spontaneous healing Cone-beam computed tomography Long-term follow-up Case report

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崇州苟家特大山体滑坡地面振动特征

四川地震 2002年第2期 28-31页

作者：袁海良任寰宋杰成都市地震局四川成都610041

成都市数字化遥测地震台网比较完整地记录下了 2 0 0 1年 5月 2 7日发生在崇州苟家的特大山体滑坡主体滑动的地面振动过程。其记录波形明显不同于地震及爆破 ,具有一定的特殊性。由记录结果推断出滑坡主体滑动的起始时间是 5月 2 7日 0... 详细信息

成都市数字化遥测地震台网比较完整地记录下了 2 0 0 1年 5月 2 7日发生在崇州苟家的特大山体滑坡主体滑动的地面振动过程。其记录波形明显不同于地震及爆破 ,具有一定的特殊性。由记录结果推断出滑坡主体滑动的起始时间是 5月 2 7日 0时 2 3分。

关键词：地面振动滑坡记录特征起始时间

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生物磁性高分子微球制备研究与应用进展

上海生物医学工程 2003年第2期24卷 42-48页

作者：任杰宋金星同济大学混凝土材料研究国家重点实验室高分子材料科学与工程系200092 同济大学高分子材料科学与工程系 200092

本文综述了磁性高分子微球的研究现状,并总结了目前常用的各种磁牲高分子微球的制备方法及其在生物医学上的应用。最后展望了磁性高分子微球的发展前景。

关键词：生物医学磁性高分子微球制备研究应用物理沉积法

SIRT3/FOXO3通路在肺癌A549细胞放疗抵抗中的作用机制研究

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中国现代医学杂志 2021年第12期31卷 28-34页

作者：方庆亮董昌盛陈荣龚卿陆松宋仁杰顾香莲王蕾顾煜恺上海中医药大学附属龙华医院放疗科上海200032 上海中医药大学附属龙华医院中医肿瘤研究所上海200032

目的探讨沉默信息调节因子3(SIRT3)/叉头转录因子O3(FOXO3)通路在肺癌A549细胞放疗抵抗中的作用。方法体外培养肺癌A549细胞,设置对照组(A549细胞)、放疗组(A549细胞+X射线照射)、SIRT3抑制剂(3-TYP)组(A549细胞+50μmol/L 3-TYP)、X射... 详细信息

目的探讨沉默信息调节因子3(SIRT3)/叉头转录因子O3(FOXO3)通路在肺癌A549细胞放疗抵抗中的作用。方法体外培养肺癌A549细胞,设置对照组(A549细胞)、放疗组(A549细胞+X射线照射)、SIRT3抑制剂(3-TYP)组(A549细胞+50μmol/L 3-TYP)、X射线+3-TYP组(A549细胞+X射线照射+50μmol/L 3-TYP)。采用CCK-8法检测各组A549细胞增殖情况;流式细胞分析仪检测各组A549细胞凋亡情况和细胞周期分布;Western blotting检测A549细胞中SIRT3、FOXO3、Bcl-2、Bax蛋白相对表达量。结果各组A549细胞培养24 h、48 h、72 h的OD值比较,经重复测量设计的方差分析:(1)不同时间点的A549细胞OD值比较,差异有统计学意义(P0.05)。放疗组、X射线+3-TYP组A549细胞凋亡率较对照组升高(P<0.05),3-TYP组较对照组降低(P<0.05),3-TYP组、X射线+3-TYP组较放疗组降低(P<0.05),X射线+3-TYP组较3-TYP组升高(P<0.05)。放疗组、X射线+3-TYP组G0/G1期A549细胞较对照组增加(P<0.05),S、G2/M期A549细胞较对照组减少(P<0.05);3-TYP组G0/G1期A549细胞较对照组降低(P<0.05),S、G2/M期A549细胞较对照组增加(P<0.05);3-TYP组、X射线+3-TYP组G0/G1期A549细胞较放疗组减少(P<0.05),S、G2/M期A549细胞较放疗组增加(P<0.05);X射线+3-TYP组G0/G1期A549细胞较3-TYP组增加(P<0.05),S、G2/M期A549细胞较3-TYP组减少(P<0.05)。放疗组、X射线+3-TYP组A549细胞SIRT3、FOXO3、Bax蛋白相对表达量较对照组升高(P<0.05),Bcl-2蛋白相对表达量较对照组降低(P<0.05);3-TYP组A549细胞SIRT3、FOXO3、Bax蛋白相对表达量较对照组降低(P<0.05),Bcl-2蛋白相对表达量较对照组升高(P<0.05);3-TYP组、X射线+3-TYP组A549细胞SIRT3、FOXO3、Bax蛋白相对表达量较放疗组降低(P<0.05),Bcl-2蛋白相对表达量较放疗组升高(P<0.05);X射线+3-TYP组A549细胞中SIRT3、FOXO3、Bax蛋白相对表达量较3-TYP组升高(P<0.05),Bcl-2蛋白相对表达量较3-TYP组降低(P<0.05)。结论肺癌A549细胞发生放疗抵抗可能与SIRT3/FOXO3通路受抑制有关。

关键词：肺肿瘤放疗抵抗沉默信息调节因子3/基因叉头转录因子3/叉头转录因子类

Drag increment induced by a small-scale forward-facing step in Mach number5 turbulent boundary layer flows

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Chinese Journal of Aeronautics 2020年第10期33卷 2491-2498页

作者： Yifei XUE jie ren Jinling LUO song FU School of Aerospace Engineering Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering University of NottinghamNottingham NG72RDUnited Kingdom Beijing Aerospace Technology Institute Beijing 100074China

Small-scale roughness elements or imperfections are inevitable over the surface of a flight *** aerodynamics of these small-scale structures is difficult to predict but may play an important role in the design of a flight vehicle at high *** forward-facing step is a typical type of roughness *** experiments have been conducted to study the aerodynamics of supersonic forward-facing step,especially with a step height larger than boundary layer ***,few studies focus on small *** improve the understanding of small-scale forwardfacing step flow,we perform a series of simulations to analyze its aerodynamic influence on a Mach number 5 turbulent boundary *** general flow structures are analyzed and *** shock waves can be induced by the step even if the step height is much smaller than the boundary layer *** significant shocks are the separation shock and the reattachment *** influenced area by the step is *** the increase of the step height,the non-dimensional influence area decreases and gradually converges when the step height reaches the boundary layer *** are two normalized distributions of the skin friction coefficient and pressure coefficient associated with step *** using the normalized parameters,a power-law relationship between the step height and the drag increment coefficient is revealed and fits the simulation results *** is further illustrated that this relationship still holds when changing the inlet angle of attack,but needs slight modification with the angle of attack.

关键词： Aerodynamics Drag increment Forward-facing step Hypersonic flow Turbulent boundary layer