Results 31 to 40 of about 17,013 (139)
ABSTRACT Objective To evaluate the impact of low‐dose aspirin (LDA) on placental size and uterine artery pulsatility index (UtA‐PI) by analyzing longitudinal changes between the first and second trimesters in pregnancies at high risk for early‐onset pre‐eclampsia (PE).
C. Trilla +7 more
wiley +1 more source
Analysis and Evaluation of Two-dimensional Hypersonic Inlet System Drag [PDF]
进气道作为超燃冲压发动机的主要部件,其阻力特性对进气道优化选型、气动减阻、一体化设计等方面都具有重要影响。在高超声速试验中,阻力的直接测量相当困难,测量误差可达到50%以上,因此有必要采用间接方法来研究进气道的阻力特性。目前,学者们采用的阻力估算方法或多或少都存在一些缺陷,无法快速应用于高超声速进气道内部阻力的工程估算。 本文提出一种快速估算进气道阻力的方法,从进气道内控制体的动量定理出发,推导出进气道阻力特性的工程估算公式;重点研究了估算公式的数据处理形式,并分别用理论分析 ...
安平
core
Impact of race‐based customization on detection of fetal growth restriction
ABSTRACT Objective Fetal growth standards determine which fetuses are diagnosed with fetal growth restriction (FGR) and become candidates for enhanced fetal monitoring. Given the existence of race‐based differences in fetal and neonatal weights, we sought to determine the impact of race‐based customization of fetal growth curves on the antenatal ...
P. Ramesh, L. Lemon, J. C. Larkin
wiley +1 more source
The physical mechanism of beam formation in dolphin’s biosonar [PDF]
作为群居的海洋哺乳动物,齿鲸类拥有着与众不同且功能强大的生物声呐系统。其生物声呐系统经过自然界的长期演化和优胜劣汰,性能已高度优化。海豚的回声定位声波能够在百米内探测到厘米级大小的物体,并对毫米级厚度的金属目标做出辨别,此外还能在探测移动目标的时候对其波束特性进行调整,其性能远远优于目前世界上任何的人工声呐。其生物声呐系统卓越的性能引起了世界上声学研究者强烈的兴趣,不但使得齿鲸类生物声呐研究成为近年来生物声学界以及国际海洋声学界的焦点,还成为新型海洋技术开发值得关注的高新科技领域 ...
魏翀
core
ABSTRACT Moderating harmful and offensive content on social media is challenging for digital platforms that seek to balance regulation and censorship across a diverse user group. It is further complicated by discrepancies between platform policies, user expectations and user experiences.
Asher Flynn +4 more
wiley +1 more source
The study of one-dimensional flow analysis model of the combustor in supersonic combustion experiments [PDF]
对公开发表的用于超声速燃烧流场分析的几种一维模型进行了研究,指出了其中存在的问题,研究结果表明:基于实验静压数据的一维模型,若不借助必要的流场测量数据或分析结果,或借助于经验性的处理方法,单靠一维假设,无法获得较为完整的一维流场分析结果。改进后的一维模型降低了数据处理过程中的不确定性,提高了对一般情况的适应能力。用编制的计算程序SSC-2对两组典型的超燃燃烧室壁面静压实验数据进行了演算 ...
俞刚, 张鹏
core
Child Rights Impact Assessment: A Policy Tool for a Rights‐Respecting Digital Environment
ABSTRACT Businesses that develop digital products and services often anticipate generic users, paying insufficient attention to the needs and rights of children who may use or be impacted by their practices. This article investigates the potential of child rights impact assessment (CRIA) as a policy tool to protect and respect children's rights in the ...
Sonia Livingstone, Kruakae Pothong
wiley +1 more source
Evaluating left atrial function and predicting the efficacy of radiofrequency catheter ablation with persistent atrial fibrillation by speckle tracking imaging [PDF]
目的:探讨应用斑点追踪技术(STI)评价持续性房颤患者经导管射频消融(RFCA)术前、术后左心房结构功能变化,并预测房颤患者经导管射频消融术后随访至术后6个月维持窦性心律的可能性。方法:对45例经皮导管射频消融术的持续性房颤患者分别于术前1周、术后24小时、术后3个月、术后6个月和25例对照组(健康志愿者)进行左房结构功能及应变率分析,测量和计算左房前后径指数(LADI)、左房面积指数(LAAI)、左房最大容积指数(LAVImax)、左房射血分数(LAEF)、E/E ...
钟小芳
core
目的研究产前三级超声检查在先天性心脏病产前筛查中的应用价值。方法回顾性分析2014年1月-2016年1月间在本院接受常规孕检的5013例孕妇的产前三级超声检查资料,将三级超声检查结果分别与产前胎儿心脏超声诊断结果及金标准:分娩后新生儿心脏超声及终止妊娠胎儿尸检结果进行对比,分析三级超声检查与两者的一致性,以金标准为参照采取ROC曲线分析三级超声的诊断价值并计算各项诊断效能指标。结果本组资料中5013例孕妇,胎儿共计5016例,先心病检出率为:三级超声1.97%、产前胎儿心脏超声1.73 ...
孙东艳 +4 more
doaj
Abstract Objectives Neonates with critical congenital heart disease (CCHD) are at risk for adverse early brain development and long‐term neurodevelopmental sequelae. Insulin‐like growth factor‐1 (IGF‐1) and insulin‐like growth factor binding protein‐3 (IGFBP‐3) are essential contributors to brain growth and maturation.
M. Nijman +33 more
wiley +1 more source

