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Numerical Simulation of Dam-Break Flows Using Radial Basis Functions: Application to Urban Flood Inundation
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作者 Abdoulhafar Halassi Bacar Said Charriffaini Rawhoudine 《American Journal of Computational Mathematics》 2024年第3期318-332,共15页
Dam-break flows pose significant threats to urban areas due to their potential for causing rapid and extensive flooding. Traditional numerical methods for simulating these events struggle with complex urban landscapes... Dam-break flows pose significant threats to urban areas due to their potential for causing rapid and extensive flooding. Traditional numerical methods for simulating these events struggle with complex urban landscapes. This paper presents an alternative approach using Radial Basis Functions to simulate dam-break flows and their impact on urban flood inundation. The proposed method adapts a new strategy based on Particle Swarm Optimization for variable shape parameter selection on meshfree formulation to enhance the numerical stability and convergence of the simulation. The method’s accuracy and efficiency are demonstrated through numerical experiments, including well-known partial and circular dam-break problems and an idealized city with a single building, highlighting its potential as a valuable tool for urban flood risk management. 展开更多
关键词 Dam-Break flows Numerical Simulation Shallow Water Equations Radial Basis functions Urban Flood Inundation
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The investigation and optimization of drag reduction in turbulent flow of Newtonian fluid passing through horizontal pipelines using functionalized magnetic nanophotocatalysts and lecithin 被引量:4
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作者 Nadia Esfandiari Reza Zareinezhad Zahra Habibi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第1期63-75,共13页
The nanophotocatalysts were synthesized in four stages and evaluated by FTIR, FESEM and VSM analysis. The influence of nanofluids containing functionalized magnetic Ti O2 nanophotocatalyst and dipalmitoylphosphatidylc... The nanophotocatalysts were synthesized in four stages and evaluated by FTIR, FESEM and VSM analysis. The influence of nanofluids containing functionalized magnetic Ti O2 nanophotocatalyst and dipalmitoylphosphatidylcholine lecithin in drag reduction of turbulent flow in four horizontal pipelines was studied. The effective parameters on drag reduction(nanoparticle concentration, surfactant concentration, p H and Re number) were investigated and optimized in each pipeline using response surface method. The drag reduction in 1/2 " galvanized, 3/4" galvanized, 1/2 "five-layer and 1/2" cuprous pipelines was found 99.1%, 92.5%, 87.6% and 85.2%, respectively. The model adequacy was measured using ANOVA. Based on the high determination coefficient, more than 95% of variance of experimental data in all pipelines was described by quadratic model. 展开更多
关键词 Drag reduction LECITHIN functionALIZED MAGNETIC nanophotocatalyst TURBULENT flow Response surface
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RELATIONS OF ENDOTHELIAL FUNCTION AND BLOOD FLOW IN BRACHIAL ARTERY AND CORONARY ARTERY 被引量:1
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作者 孙寅光 沈卫峰 +1 位作者 施仲伟 张大东 《Journal of Shanghai Second Medical University(Foreign Language Edition)》 2003年第1期41-45,57,共6页
Objective:To determine the relations between endothelium-dependent vasodilator function and blood flow in the brachial and coronary arteries in patients with suspected coronary artery disease.Methods:Twenty-eight pati... Objective:To determine the relations between endothelium-dependent vasodilator function and blood flow in the brachial and coronary arteries in patients with suspected coronary artery disease.Methods:Twenty-eight patients with suspected coronary artery disease underwent brachial artery endothelial function test by using high-resolution B-mode ultrasound before coronary angiography(CAG)and coronary flow reserve(CFR)test by using intracoronary Doppler technique.The correlation of coronary artery dilatation induced by an increase in blood flow after intracoronary adenosine infusion and brachial artery flow-mediated dilatation(FMD) following reactive hyperemia was evaluated.The relation between the change of brachial artery blood flow and CFR was also studied.Results:There was a positive correlation between brachial FMD and percent change of coronary diameter after adenosine infusion(12.50%±9.35% vs 11.38%±7.55%,r=0.425,P=0.02).There was also a weak negative relation between brachial flow change following reactive hy-peremia and CFR(r=-0.397,P=0.04).Conclusion:There is a correlation between the coronary endo-thelial function and the CFR by ultrasonic determination of brachial flow changes following reactive hyperemia. 展开更多
关键词 ultrasound reactive hyperemia brachial artery endothelial function coronary flow reserve
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Perfect Combination of Architectural Functions and Flow Lines: Study on Roof Garden of Frank Gehry's Walt Disney Concert Hall
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作者 WANG Haiou 《Journal of Landscape Research》 2016年第2期21-22,26,共3页
By exploring the space and the design techniques of roof garden in Frank Gehry's Walt Disney Concert Hall, this paper made further research on the combination of architectural functions and pedestrian fl ow lines,... By exploring the space and the design techniques of roof garden in Frank Gehry's Walt Disney Concert Hall, this paper made further research on the combination of architectural functions and pedestrian fl ow lines, and attempted to summarize the unique design techniques of Frank Gehry by analyzing his works, improve and develop design theories of roof garden, and attract more attention from the public to roof garden design. 展开更多
关键词 Walt Disney Concert Hall Roof garden Space form function flow lines
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基于4D Flow CMR技术评价心肌纤维化对肥厚型心肌病患者左室舒张功能障碍的影响
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作者 郑琰 马丽荣 +5 位作者 郭家璇 张怀榕 孙潇 孙凯 王一帆 朱力 《磁共振成像》 CAS CSCD 北大核心 2024年第5期119-125,共7页
目的采用四维血流(four-dimensional flow,4D Flow)心脏磁共振成像(cardiac magnetic resonance,CMR)技术对肥厚型心肌病(hypertrophic cardiomyopathy,HCM)患者是否存在左心室舒张功能障碍进行评估,探讨心肌纤维化对HCM患者左心室舒张... 目的采用四维血流(four-dimensional flow,4D Flow)心脏磁共振成像(cardiac magnetic resonance,CMR)技术对肥厚型心肌病(hypertrophic cardiomyopathy,HCM)患者是否存在左心室舒张功能障碍进行评估,探讨心肌纤维化对HCM患者左心室舒张功能的影响。材料与方法前瞻性纳入44例HCM患者,根据患者是否合并晚期钆增强(late gadolinium enhancement,LGE)分为HCM LGE(+)组(25例)和HCM LGE(-)组(19例),同期纳入31例健康对照者。三组人群进行3.0 T磁共振稳态自由进动序列及4D Flow序列扫描。采用CVI42后处理软件进行分析,包括心功能参数、二尖瓣血流速度参数。使用单因素方差分析或Mann-Whitney U检验对三组受试者临床资料及影像学参数进行比较;并对二尖瓣水平舒张早期平均血流速度(E)与舒张期整体室壁峰值厚度(global peak wall thickness,GPWT)、左心室质量(left ventricular mass,LVmass)进行相关性分析。结果HCM患者的LVmass及GPWT均大于健康对照组,且伴有心肌纤维化较不伴有心肌纤维化的HCM患者的GPWT增大更加明显[HCM LGE(+)组vs.HCM LGE(-)组vs.健康对照组];[LVmass:157.34(122.24,194.38)g vs.148.29(131.79,189.83)g vs.85.73(73.00,94.02)g;GPWT:20.04(16.76,24.99)mm vs.17.46(16.19,19.99)mm vs.9.47(8.35,10.92)mm](P<0.001);伴有心肌纤维化的HCM患者舒张早期平均血流速度峰值(E峰)低于不伴有心肌纤维化的HCM患者,且均较健康对照组低[HCM LGE(+)组vs.HCM LGE(-)组vs.健康对照组:(30.03±11.33)cm/s vs.(38.05±12.03)cm/s vs.(47.44±10.82)cm/s](P<0.001);而舒张晚期平均血流速度峰值(A峰)在三组间均无显著性差异;且伴有心肌纤维化的HCM患者较健康对照组的E/A值明显减低(1.10±0.61 vs.1.74±0.85)(P<0.05)。舒张期早期二尖瓣水平的平均血流速度与GPWT和LVmass均呈负相关(r=-0.593/r=-0.371,P<0.001/P=0.001)。结论基于4D Flow CMR不仅可以从三维角度对血流速度进行准确测量,同时能从血流动力学方面定量评估HCM患者的左室舒张功能障碍及心肌纤维化对HCM患者左心室舒张功能的影响。 展开更多
关键词 肥厚型心肌病 心肌纤维化 左室舒张功能 四维血流心脏磁共振 磁共振成像
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Functional connectivity and information flow in cerebral motor regions of healthy people following finger movement training
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作者 Zeqiang Yang Dongmei Hao Ying Li Yanping Bai 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第9期710-714,共5页
BACKGROUND:Neuro-rehabilitative training has been shown to promote motor function recovery in stroke patients,although the underlying mechanisms have not been fully clarified.OBJECTIVE:To investigate the effects of ... BACKGROUND:Neuro-rehabilitative training has been shown to promote motor function recovery in stroke patients,although the underlying mechanisms have not been fully clarified.OBJECTIVE:To investigate the effects of finger movement training on functional connectivity and information flow direction in cerebral motor areas of healthy people using electroencephalogram (EEG).DESIGN,TIME AND SETTING:A self-controlled,observational study was performed at the College of Life Science and Bioengineering,Beijing University of Technology between December 2008 and April 2009.PARTICIPANTS:Nineteen healthy adults,who seldom played musical instruments or keyboards,were included in the present study.METHODS:Specific finger movement training was performed,and all subjects were asked to separately press keys with their left or right hand fingers,according to instructions.The task comprised five sessions of test train test train-test.Thirty-six channel EEG signals were recorded in different test sessions prior to and after training.Data were statistically analyzed using one-way analysis of variance.MAIN OUTCOME MEASURES:The number of effective performances,correct ratio,average response time,average movement time,correlation coefficient between pairs of EEG channels,and information flow direction in motor regions were analyzed and compared between different training sessions.RESULTS:Motor function of all subjects was significantly improved in the third test comparedwith the first test (P〈 0.01).More than 80% of connections were strengthened in the motor-related areas following two training sessions,in particular the primary motor regions under the C4 electrode.Compared to the first test,a greater amount of information flowed from the Cz and Fcz electrodes (corresponding to supplementary motor area) to the C4 electrode in the third test.CONCLUSION:Finger task training increased motor ability in subjects by strengthening connections and changing information flow in the motor areas.These results provided a greater understanding of the mechanisms involved in motor rehabilitation. 展开更多
关键词 motor cortex functional connectivity information flow direction ELECTROENCEPHALOGRAM
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A GENERAL FUNCTIONAL EQUATION GOVERNING THE MOTION OF A FLUID FLOW
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作者 张杰 方国洪 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1995年第2期119-123,共5页
A time-correlated random field bescribing the general flow is defined. A time-correlated functionalequation governing the evolution of its characteristic functional is derived.
关键词 flow RANDOM field CHARACTERISTIC functionAL
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Do Continuous Flow LVADS Improve Diastolic Dysfunction? 被引量:1
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作者 Nandini Nair Sudhir Thotakura Enrique Gongora 《Open Journal of Organ Transplant Surgery》 2014年第3期23-28,共6页
Background: Ventricular assist devices are now used as a bridge to recovery/decision/transplant or as destination therapy in end-stage heart failure. Continued improvements in technology and pump design have made impl... Background: Ventricular assist devices are now used as a bridge to recovery/decision/transplant or as destination therapy in end-stage heart failure. Continued improvements in technology and pump design have made implantation an easier process with reduced operative risks and pump-related adverse events. Considering the beneficial effects of these devices in the clinical setting, it seemed logical to address the long-term effect of the continuous flow pumps on diastolic dysfunction. Methods: This study addresses the effect of HeartMate IITM(HMII) support for 284+/-97 days on echocardiographic parameters of diastolic function. Data from fifteen patients was retrospectively studied status post left ventricular assist device (LVAD) implantation. The data at approximately 1-year post implantation was compared with that obtained prior to implantation. Statistical analyses were performed using the Microsoft Excel Program/MSExcel Stats. Echocardiographic measurements were carried out in accordance with the American Society of Echocardiography guidelines. Results: Of all the echocardiographic parameters assessed only E/Ea and calculated left atrial pressure (LAP) showed a statistically significant decrease. Two parameters that showed a trend towards significance are Ea (septal) and global functional index (p = 0.05). Conclusions: Continuous Flow LVAD support appears to improve diastolic dysfunction. This study has limitations in that we used a single type of continuous flow device (HeartMate IITM) and was conducted as a retrospective analysis. Further studies with larger populations and longer support are required to validate this finding. 展开更多
关键词 CONTINUOUS flow Device DIASTOLIC function HeartMate IITM LEFT VENTRICULAR Assist Devise
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Developing theory of probability density function for stochastic modeling of turbulent gas-particle flows
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作者 Lixing ZHOU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2018年第7期1019-1030,共12页
Turbulent gas-particle flows are studied by a kinetic description using a prob- ability density function (PDF). Unlike other investigators deriving the particle Reynolds stress equations using the PDF equations, the... Turbulent gas-particle flows are studied by a kinetic description using a prob- ability density function (PDF). Unlike other investigators deriving the particle Reynolds stress equations using the PDF equations, the particle PDF transport equations are di- rectly solved either using a finite-difference method for two-dimensional (2D) problems or using a Monte-Carlo (MC) method for three-dimensional (3D) problems. The proposed differential stress model together with the PDF (DSM-PDF) is used to simulate turbulent swirling gas-particle flows. The simulation results are compared with the experimental results and the second-order moment (SOM) two-phase modeling results. All of these simulation results are in agreement with the experimental results, implying that the PDF approach validates the SOM two-phase turbulence modeling. The PDF model with the SOM-MC method is used to simulate evaporating gas-droplet flows, and the simulation results are in good agreement with the experimental results. 展开更多
关键词 probability density function(PDF)modeling turbulent flow gas-particleflow
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Rheological Behaviour for Polymer Melts and Concentrated SolutionsPart Ⅱ: Material Function with Nagai Chain Constraints and Determination of Their Parameters from Flow Curves 被引量:3
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作者 Mingshi SONG Sizhu WU and Xiuyun DU(Research Institute of Polymeric Materials, Beijing University of Chemical Technology, Beijing, 100029, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1995年第2期141-152,共12页
An integral constitutive equation and a set of material functions for describing the strain history of polymer melts were formulated in terms of the Cauchy-Green and Finger tensors. A simple memory function and the de... An integral constitutive equation and a set of material functions for describing the strain history of polymer melts were formulated in terms of the Cauchy-Green and Finger tensors. A simple memory function and the dependence of ηo and τt on M3.4 were derived from the theory of non-linear viscoelasticity with constraints of entanglements for polymer melts and substituted into the Oldroye-Walters-Fredickson constitutive equation. An integral constitutive equation for polymer melts was consequently obtained. Some material functions of the constitutive equation related to certain 'test flow' are examined as follows : (1) simple steady shear flow; (2) steady elongation flow; (3) small-amplitude oscillatory shear flow; (4) stress growth upon the inception of steady shear elongation flow; (5) stress relaxation (modulus and compllance). These theoretical relations for simple steady shear flow were compared with experimental data from our laboratory and references for various polymer melts and concentrated solutions. A good agreement between the theory and experiment was achieved. 展开更多
关键词 LDPE Material function with Nagai Chain Constraints and Determination of Their Parameters from flow Curves Rheological Behaviour for Polymer Melts and Concentrated SolutionsPart flow GR
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Study of Nonlinear Earthquake Flow Functions and Their Application to the Space Increased Probability of Strong Earthquake (SIP)
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作者 Wang Xiaoqing and Huang DeyuCenter for Analysis and Prediction, CSB, Beijing 100036, China 《Earthquake Research in China》 1998年第3期37-47,共11页
The definition and abnormality discriminatory criteria of earthquake flow function are introduced in this paper based on the algorithm of Space Increased Probability (SIP). Nine earthquake flow functions were defined ... The definition and abnormality discriminatory criteria of earthquake flow function are introduced in this paper based on the algorithm of Space Increased Probability (SIP). Nine earthquake flow functions were defined by the method. The retrospect test that applied the SIP algorithm with the nonlinear earthquake flow function to 7 earthquakes, which occurred from 1975 to 1989 in Eastern China, with a magnitude of 6 or greater depicted that 6 of the 7 strong earthquakes (86%) were located in the SIP areas, and the SIP covers about 32% of the total research time-space domain. These suggest that the R-value, an effective scale for earthquake forecast, is 54% and may imply that the nonlinear earthquake flow function introduced in this paper can be applied to the intermediate-term earthquake forecast research. 展开更多
关键词 NONLINEAR EARTHQUAKE flow function SPACE INCREASED PROBABILITY of strong earthquake.
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Flow cytometry for the assessment of animal sperm ntegrity and functionality: state of the art 被引量:1
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作者 Md. Sharoare Hossain Anders Johannisson +3 位作者 Margareta Wallgren Szabolcs Nagy Amanda Pimenta Siqueira Heriberto Rodriguez-Martinez 《Asian Journal of Andrology》 SCIE CAS CSCD 2011年第3期406-419,511,共15页
Flow cytometry is now a recognized methodology within animal spermatology, and has moved from being a research tool to become routine in the assessment of animal semen destined to breeding. The availability of 'bench... Flow cytometry is now a recognized methodology within animal spermatology, and has moved from being a research tool to become routine in the assessment of animal semen destined to breeding. The availability of 'bench-top' flow cytometers and of newer and versatile markers for cell structure and function had allowed the instrumentation to measure more sperm parameters, from viability to reactiveness when exposed to exogenous stimuli, and to increase our capabilities to sort spermatozoa for potential fertilizing capacity, or chromosomal sex. The present review summarizes the state of the art regarding flow cytometry applied to animal andrology, albeit keeping an open comparative intent. It critically evaluates the present and future capabilities of flow cytometry for the diagnostics of potential fertility and for the development of current reproductive technologies such as sperm freezing, sperm selection and sperm sorting. The flow cytometry methods will probably further revolutionize our understanding of the sperm physiology and their functionality, and will undoubtedly extend its application in isolating many uncharacterized features of spermatozoa. However, continuous follow-up of the methods is a necessity owing to technical developments and the complexity of mapping spermatozoa. 展开更多
关键词 ANIMALS FERTILITY flow cytometry semen analysis SPERMATOZOA sperm functionality sperm intactness
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Dissipation function in turbulent plane Poiseuille and Couette flows subject to spanwise rotations
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作者 Zhenhua XIA Yipeng SHI +1 位作者 Qingdong CAI Jie GAI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第2期185-192,共8页
The dissipation function in turbulent plane Poiseuille flows(PPFs) and plane Couette flows(PCFs) subject to spanwise rotations is analyzed. It is found that, in the PCFs without system rotations, the mean part is cons... The dissipation function in turbulent plane Poiseuille flows(PPFs) and plane Couette flows(PCFs) subject to spanwise rotations is analyzed. It is found that, in the PCFs without system rotations, the mean part is constant while the fluctuation part follows a logarithmic law, resulting in a similar logarithmic skin friction law as PPFs.However, if the flow system rotates in the spanwise direction, no obvious dependence on the rotation number can be evaluated. In the PPFs with rotations, the dissipation function shows an increase with the rotation number, while in the PCFs with rotations,when the rotation number increases, the dissipation function first decreases and then increases. 展开更多
关键词 dissipation function spanwise rotation plane Poiseuille flow(PPF) plane Couette flow(PCF)
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站城人一体化发展下铁路枢纽功能与客流需求分析 被引量:1
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作者 吴琼 《城市轨道交通研究》 北大核心 2025年第1期154-158,163,共6页
[目的]在站城人一体化发展下,铁路客运枢纽在承担交通功能与城市开发功能的基础上,升级为提供情感联系与寄托的新型城市空间,枢纽的服务属性和承载的客流群体发生较大变化,需立足需求端的变化研究站城人一体化发展下铁路客运枢纽的功能... [目的]在站城人一体化发展下,铁路客运枢纽在承担交通功能与城市开发功能的基础上,升级为提供情感联系与寄托的新型城市空间,枢纽的服务属性和承载的客流群体发生较大变化,需立足需求端的变化研究站城人一体化发展下铁路客运枢纽的功能特征和客流需求。[方法]基于站城人一体化发展的阶段性特征及其对铁路枢纽承担客流的影响,分析了新型铁路客运枢纽的功能变化及其承担的客流构成,具体包括基于交通服务的趋势客流、城市开发诱增的衍生客流、供给动态调整的韧性客流等几部分,在传统交通预测四阶段法的基础上提出每种情景客流需求的预测思路及方法,并以西安东站为例进行验证分析。[结果及结论]枢纽客流呈现出交通功能客流前期为主、城市功能客流逐步增长、韧性客流短期趋稳的发展态势。综合三部分客流分析,初步预测西安东枢纽远期高峰小时的客流总量约为3.0万~3.2万人次/h。通过细化枢纽各部分客流需求的预测方法,可为新型枢纽的功能配置、设施布局、客运组织等提供科学可靠的依据。 展开更多
关键词 站城人一体化 铁路枢纽 功能特征 客流结构 需求分析
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孕妇血清sFt-1l、FGF19和血管内皮功能改变与PE发病风险的关联
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作者 侯祎 唐建芬 +1 位作者 吴蓓娇 朱燕萍 《中国计划生育学杂志》 2025年第6期1415-1419,共5页
目的:探究子痫前期(PE)孕妇血清可溶性Fms样酪氨酸激酶-1(sFlt-1)、成纤维生长因子19(FGF19)水平及血管内皮功能改变与PE发病风险关系。方法:选取2022年7月13日-2024年5月1日本院就诊的PE孕妇60例为观察组,同期产前检查正常妊娠孕妇60... 目的:探究子痫前期(PE)孕妇血清可溶性Fms样酪氨酸激酶-1(sFlt-1)、成纤维生长因子19(FGF19)水平及血管内皮功能改变与PE发病风险关系。方法:选取2022年7月13日-2024年5月1日本院就诊的PE孕妇60例为观察组,同期产前检查正常妊娠孕妇60例为对照组,分析临床资料,比较血清sFlt-1、FGF1水平及血管内皮功能,记录其右侧肱动脉内皮血管扩张(FMD)值,探讨各指标与PE发病关系。结果:观察组收缩压、舒张压、低蛋白血症发生率均高于对照组,25-羟基维生素D325-(OH)D3水平低于对照组,血清sFlt-1(1215.13±78.16 pg/ml)、FGF19(271.41±19.46 ng/L)水平和FMD值(17.13±2.13)%均高于对照组(268.16±25.45 pg/ml、221.12±16.12 ng/L、12.22%±1.58%)(均P<0.05)。行logistic回归分析,孕妇血清sFlt-1、FGF19水平和FMD值升高是PE发生的独立危险因素,且3指标诊断孕妇PE均有较高价值,其受试者工作特征曲线下面积(AUC)值分别为0.881、0.929、0.859。结论:PE孕妇血清sFlt-1、FGF19水平和FMD值均异常升高,且均为PE发生的独立危险因素,并对PE发生均有较高诊断价值,可为临床早期筛查高危人群和实施预防干预提供参考依据。 展开更多
关键词 子痫前期 可溶性Fms样酪氨酸激酶-1 成纤维生长因子19 血管内皮功能 右侧肱动脉内皮血管扩张值 风险因素 诊断价值
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Functionality Semantics of Predicate Data Flow Diagram
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作者 高晓雷 缪淮扣 刘玲 《Journal of Shanghai University(English Edition)》 CAS 2004年第3期309-316,共8页
SOZL (structured methodology + object-oriented methodology + Z language) is a language that attempts to integrate structured method, object-oriented method and formal method. The core of this language is predicate dat... SOZL (structured methodology + object-oriented methodology + Z language) is a language that attempts to integrate structured method, object-oriented method and formal method. The core of this language is predicate data flow diagram (PDFD). In order to eliminate the ambiguity of predicate data flow diagrams and their associated textual specifications, a formalization of the syntax and semantics of predicate data flow diagrams is necessary. In this paper we use Z notation to define an abstract syntax and the related structural constraints for the PDFD notation, and provide it with an axiomatic semantics based on the concept of data availability and functionality of predicate operation. Finally, an example is given to establish functionality consistent decomposition on hierarchical PDFD (HPDFD). 展开更多
关键词 predicate data flow diagram (PDFD) predicate operation (PO) hierarchical predicate data flow diagram (HPDFD) AVAILABILITY functionality semantics.
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早期量化相关踝泵运动对预防股骨骨折术后患者深静脉血栓形成的影响
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作者 张金姬 邓娟 +1 位作者 朱欢欢 谢丽琼 《中国医学创新》 2025年第17期80-84,共5页
目的:探讨早期量化相关踝泵运动对预防股骨骨折术后患者深静脉血栓形成的效果。方法:选择2023年1月—2024年5月三明市第二医院收治的86例股骨骨折患者。以随机数字表法分为对照组、研究组,各43例。对照组应用常规干预,研究组在对照组基... 目的:探讨早期量化相关踝泵运动对预防股骨骨折术后患者深静脉血栓形成的效果。方法:选择2023年1月—2024年5月三明市第二医院收治的86例股骨骨折患者。以随机数字表法分为对照组、研究组,各43例。对照组应用常规干预,研究组在对照组基础上加用早期量化相关踝泵运动干预。两组均干预7 d。比较两组下肢深静脉血栓发生情况、下肢静脉血流速度及凝血功能。结果:研究组下肢深静脉血栓发生率显著低于对照组,差异有统计学意义(P<0.05)。干预后,两组下肢静脉平均流速、峰值流速均高于干预前,且研究组均高于对照组,差异均有统计学意义(P<0.05)。干预后,两组活化部分凝血活酶时间(APTT)、凝血酶原时间(PT)、凝血酶时间(TT)均长于干预前,纤维蛋白原(FIB)、D-二聚体(D-D)均低于干预前,且研究组PT、APTT、TT均长于对照组,D-D、FIB均低于对照组,差异均有统计学意义(P<0.05)。结论:股骨骨折患者术后应用早期量化相关踝泵运动可有效提升下肢静脉血流速度,预防下肢深静脉血栓形成。 展开更多
关键词 股骨骨折 早期量化相关踝泵运动 深静脉血栓 凝血功能 血流速度
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基于子午流注理论指导雷火灸联合中药贴敷治疗老年功能性消化不良的临床研究 被引量:1
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作者 张娟 邵建国 +4 位作者 李民 达坤林 乔娇娇 蒋文 张玉 《南通大学学报(医学版)》 2025年第3期211-215,共5页
目的:分析子午流注雷火灸(辰时)联合中药贴敷(巳时)对老年功能性消化不良(functional dyspepsia,FD)患者的临床疗效。方法:选取2022年1月—2024年12月在南通市第三人民医院中医科住院的120例老年FD患者,随机平分为对两组,对照组采用口... 目的:分析子午流注雷火灸(辰时)联合中药贴敷(巳时)对老年功能性消化不良(functional dyspepsia,FD)患者的临床疗效。方法:选取2022年1月—2024年12月在南通市第三人民医院中医科住院的120例老年FD患者,随机平分为对两组,对照组采用口服多潘立酮片治疗,观察组在对照组基础上采用子午流注雷火灸(辰时)联合中药贴敷(巳时)治疗,两组患者均治疗2周。比较两组患者的临床疗效,治疗前后的中医证候积分,内脏敏感性指数和健康调查简表(short form 36 health survey,SF-36)评分,血清胃肠激素水平变化以及不良反应情况。结果:观察组的总体临床疗效明显高于对照组(P<0.05);观察组的主、次中医证候积分明显低于对照组(P<0.05);观察组内脏敏感性指数较对照组降低更明显(P<0.05),观察组SF-36评分较对照组提高更明显(P<0.05);观察组血清胃动素、胃泌素水平较对照组显著升高(P<0.05);两组不良反应情况比较差异无统计学意义(P>0.05)。结论:在子午流注理论的指导下,雷火灸与中药贴敷的联合应用能显著改善老年FD患者临床表现,调节胃肠动力,提高老年患者的生活质量。 展开更多
关键词 功能性消化不良 子午流注 雷火灸 中药贴敷 胃肠激素 老年人
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高度近视黄斑裂孔性视网膜脱离术后黄斑微结构变化及其与视功能的相关性 被引量:1
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作者 杨娜 温晓英 张月玲 《国际眼科杂志》 2025年第2期281-285,共5页
目的:观察高度近视黄斑裂孔性视网膜脱离(MHRD)患者术后光学相干断层扫描成像(OCT)及光学相干断层扫描血管成像(OCTA)检查指标的变化特征及其与视功能的相关性。方法:选取2019-01/2023-10于保定市第一中心医院进行治疗的高度近视MHRD患... 目的:观察高度近视黄斑裂孔性视网膜脱离(MHRD)患者术后光学相干断层扫描成像(OCT)及光学相干断层扫描血管成像(OCTA)检查指标的变化特征及其与视功能的相关性。方法:选取2019-01/2023-10于保定市第一中心医院进行治疗的高度近视MHRD患者78例为研究对象,均行玻璃体切除联合内界膜填塞术治疗,观察术后1、3、6 mo时患者最佳矫正视力(BCVA)与OCT、OCTA指标变化特征,包括黄斑中心凹脉络膜毛细血管层血流面积(CBFA)、血流密度与椭圆体带缺损直径(DEZA),并采用Pearson相关分析与多元线性回归分析术后不同时间点BCVA与CBFA、DEZA、血流密度的相关性。结果:术后1、3、6 mo时患者BCVA分别为1.75±0.79、1.49±0.53、1.08±0.44,各时间点比较均有差异(均P<0.05)。术后1、3、6 mo,患者CBFA分别为1.67±0.24、1.82±0.13、1.94±0.15 mm 2,DEZA分别为813.27±453.16、590.89±421.38、427.58±385.34μm,血流密度分别为24.36±7.81、27.74±8.12、31.54±8.59,各项指标各时间点比较均有差异(均P<0.05)。Pearson相关性分析显示,术后1 mo,高度近视MHRD患者的DEZA、血流密度与BCVA无相关性(均P>0.05),CBFA与BCVA(LogMAR)呈负相关(P<0.05);术后3、6 mo时,高度近视MHRD患者的CBFA、血流密度与BCVA(LogMAR)呈负相关,DEZA与BCVA(LogMAR)呈正相关(均P<0.05)。多元线性回归分析显示,术后3、6 mo,CBFA、血流密度及DEZA均为BCVA的重要影响因素(均P<0.05)。结论:高度近视MHRD患者术后视功能逐渐提升,且与术后CBFA、DEZA、血流密度密切相关,建议术后定期监测OCT、OCTA指标变化。 展开更多
关键词 高度近视 黄斑裂孔性视网膜脱离 光学相干断层扫描成像 光学相干断层扫描血管成像 视功能 黄斑中心凹脉络膜毛细血管层血流面积 椭圆体带缺损直径 血流密度
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基于注意力机制和能量函数的动作识别算法
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作者 王丽芳 吴荆双 +1 位作者 尹鹏亮 胡立华 《计算机应用》 北大核心 2025年第1期234-239,共6页
针对零样本动作识别(ZSAR)算法的框架缺乏结构性指导的问题,以基于能量的模型(EBM)指导框架设计,提出基于注意力机制和能量函数的动作识别算法(ARAAE)。首先,为了得到EBM的输入,设计了光流加3D卷积(C3D)架构的组合以提取视觉特征,从而... 针对零样本动作识别(ZSAR)算法的框架缺乏结构性指导的问题,以基于能量的模型(EBM)指导框架设计,提出基于注意力机制和能量函数的动作识别算法(ARAAE)。首先,为了得到EBM的输入,设计了光流加3D卷积(C3D)架构的组合以提取视觉特征,从而达到空间去冗余的效果;其次,将视觉Transformer(ViT)用于视觉特征的提取以减少时间冗余,同时利用ViT配合光流加C3D架构的组合以减少空间冗余,从而获得非冗余视觉空间;最后,为度量视觉空间和语义空间的相关性,实现能量评分评估机制,设计联合损失函数来进行优化实验。采用6个经典ZSAR算法及近年文献里的算法在两个数据集HMDB51和UCF101进行实验的结果表明:相较于CAGE(Coupling Adversarial Graph Embedding)、Bi-dir GAN(Bi-directional Generative Adversarial Network)和ETSAN(Energy-based Temporal Summarized Attentive Network)等算法,在平均分组的HMDB51数据集上,ARAAE平均识别准确率提升至(22.1±1.8)%,均明显优于对比算法;在平均分组的UCF101数据集上,ARAAE的平均识别准确率提升至(22.4±1.6)%,略优于对比算法;在以81/20为分割方式的UCF101数据集上,ARAAE的平均识别准确率提升至(40.2±2.6)%,均大于对比算法。可见,ARAAE在ZSAR中能有效提高识别性能。 展开更多
关键词 零样本动作识别 能量函数 注意力机制 光流法 视觉特征
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