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关键词： coronary artery disease   epidemiology   hypertrophy   obesity   sudden death   BMI   body mass index   CAD   coronary artery disease   CPAP   continuous positive airway pressure   ECG   electrocardiography   GLP   glucagon-like peptide   HF   heart failure   ICD   implantable cardioverter-defibrillator   MI   myocardial infarction   OSA   obstructive sleep apnea   SAD   sagittal abdominal diameter   SCA   sudden cardiac arrest   SCD   sudden cardiac death   VA   ventricular arrhythmia   WHR   waist-to-hip ratio  

摘要： In recent decades, the prevalence of obesity has increased significantly, leading to an epidemic at the global level. Obesity is associated with various metabolic alterations and increases the risk of cardiovascular disease. The most devastating manifestation of cardiovascular disease is sudden cardiac death (SCD), leading to substantial years of potential life lost worldwide. Obesity-related SCD is an increasingly important public health problem and warrants a specific investigative focus on improved risk stratification and prevention. In this review, we summarize the current evidence regarding management of SCD in obesity and discuss knowledge gaps as well as future directions in this field.

关键词： acute coronary syndrome   hypertensive disorders of pregnancy   MINOCA   myocardial infarction   nonobstructive coronary artery disease   sex-specific risk factors   ACS   acute coronary syndrome   BMI   body mass index   CABG   coronary artery bypass grafting   CAD   coronary artery disease   CVD   cardiovascular disease   HDP   hypertensive disorders of pregnancy   MI   myocardial infarction   MINOCA   myocardial infarction with nonobstructive coronary arteries   PCI   percutaneous coronary intervention   PE   preeclampsia   REP   Rochester Epidemiology Project  

摘要： Angiographic evidence of the anatomy of coronary arteries and the type of coronary artery lesions in women with a history of hypertensive disorders of pregnancy (HDP) are poorly documented.

关键词： Material extrusion   Dimension accuracy   Model conversion   STL   G-code  

摘要： In this study, an analysis was conducted to quantify errors in the additive manufacturing process, with a focus on comparing data files. The primary objective was to minimise the reliance on physical testing of produced components by favouring verification within a virtual environment. The initial focus was on the conversion from the CAD (Computer-Aided Design) model to the STL (Standard Tessellation Language) file, where discrepancies between the two formats were identified. To achieve optimal meshing, it is crucial to configure conversion parameters effectively, avoiding both detail loss and the handling of excessively large files. Following this, a comparison between STL files and reconstructed G-code files was conducted, uncovering further approximations introduced by the most commonly used slicers. In conclusion, the analysis highlights that both the quality of the mesh and the slicing phase significantly impact the final component. Understanding these factors is essential for achieving an optimal print outcome. © 2024 The Authors

关键词： 甘蓝   裂球性   木质素   肉桂醇脱氢酶(CAD)   基因表达  

摘要： 以易裂球、耐裂球甘蓝为试材,采用间苯三酚染色与转录组学相结合的方法,研究了甘蓝裂球性状与木质素含量之间的关系,以期揭示木质素在甘蓝裂球形成过程中的潜在作用。结果表明:易裂球甘蓝叶柄的木质化程度以及叶片的木质素含量均比耐裂球甘蓝略高;在甘蓝全基因组范围鉴定到10个木质素合成关键基因肉桂醇脱氢酶基因(CAD),分布于甘蓝6条染色体上;甘蓝CAD基因之间外显子-内含子结构差异较大;大部分CAD基因在2种甘蓝叶片中均有表达,其中5个CAD基因(BoCAD4、BoCAD7-LF、BoCAD7-MF2a、BoCAD7-MF2b和BoCAD9-MF2)在易裂球甘蓝中的表达量高于耐裂球甘蓝,与木质素测定结果一致。综上可知,木质素含量与甘蓝裂球性状无显著相关性,木质素并不是影响甘蓝裂球性状的主要因素。

关键词： CAD   CAM   mechanical part design   mechanical part manufacturing  

摘要： This paper comprehensively discusses the core applications and innovation strategies of CAD/CAMtechnology in mechanical parts manufacturing, with a special focus on automatic path planning, CNCprogramming, multi-axis and high-speed machining technology, as well as intelligent upgrading ofquality control and production management. By introducing advanced models such as DeepGraph Neural Reinforcement Learning Path Planner(DGNet-RPP), it demonstrates how to utilize thefusion of Deep Reinforcement Learning and Graph Neural Network to adaptively optimize the toolpath planning of complex parts to ensure machining efficiency and accuracy. Meanwhile, theimportance of optimization and post-processing techniques for NC programming, such as simulatedannealing and ant colony optimization, is emphasized to improve machining efficiency and codeadaptability. The implementation of multi-axis machining and high-speed machining technology hasgreatly promoted the progress of complex parts machining accuracy and surface quality, especially inhigh-end manufacturingfields such as aerospace. In addition, the article also explains the key role ofCAM systems in quality control and production scheduling, how to ensure the quality of parts throughreal-time monitoring and data analysis, as well as through advanced planning and scheduling tooptimize the production process, reduce costs, and improve market responsiveness.

关键词： Accuracy   Intraoral scanner   Edentulous   Implant   Auxiliary devices   IOS   Intraoral scanners   PG   Photogrammetry   RMS   Root Mean Square   PAD   Prefabricated auxiliary devices   STL   Standard Tessellation Language   CAD   Computed Aided Design   DLP   Digital Light Processing  

摘要： This study aimed to evaluate the impact of prefabricated auxiliary devices (PADs) in different optical properties and shapes on the accuracy of digital implant impressions.

关键词： 本构关系   屈服函数   剑桥模型   泰勒级数展开  

摘要： 采用泰勒级数展开的方法由修正剑桥模型屈服函数得到新的P-L屈服函数,用于合理描述不同类型土的屈服面。该屈服函数满足临界状态力学的基本假定,屈服面与临界状态线的交点处的法向量始终垂直于p轴,当采用相关联的流动法则时,土体达到临界状态后不会产生额外的体积变形。修正P-L屈服函数所引入的形状因子α为临界状态有效平均主应力与前期固结应力之间的比值,增大α会导致屈服面沿着临界状态线向外扩张,材料的弹性区间也随之增大。剑桥模型和修正剑桥模型的屈服函数可以视作本文提出的屈服函数的特例,分别对应α为0.368和0.5时的情形,通过对Pancrudo堆石料的屈服面进行拟合,可以看出修正P-L屈服函数能够更好地描述屈服面的真实几何形状。在此基础上,可以采用该屈服函数对修正剑桥模型进行拓展以提升其对不同类型土的适用性。将模型计算结果与正常固结重塑Weald黏土和Kaolin黏土的不排水三轴压缩试验结果进行对比分析,发现适当调整屈服面的几何形状有助于提高模型的计算精度,尤其是对于Kaolin黏土,在不排水剪切条件下可以计算得到更为准确的不排水抗剪强度和有效应力路径。鉴于拓展后的修正剑桥模具有形式简单且计算精度高等优点,其在岩土变形计算领域有着广泛的应用前景。

摘要： Background: The co-existence of lower extremity arterial disease (LEAD) is associated with poor long term cardiovascular outcomes in patients with coronary artery disease (CAD). Most of patients with LEAD are asymptomatic and are often diagnosed c...

关键词： 金工实训   CAD技术   CAM技术   教学改革  

摘要： 针对目前金工实训课程教学中存在的教学内容碎片化、教学方法单一、设备老化落后等问题,将CAD参数化建模与装配仿真、CAM虚拟加工仿真等技术融入教学,进行了教学模式的改革和实践。实践成果表明,该模式的应用显著提升了学生的专业技能水平,有利于其专业知识体系的构建和创新能力的培养,有效解决了传统实训与产业需求脱节的矛盾,为工科专业教育的产教融合改革提供了成功案例。