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关键词： Cytomegalovirus   Organ transplantation   Cardiovascular events   Meta-analysis   CMV   Cytomegalovirus   OT   Organ Transplantation   CV   Cardiovascular   CVE   Cardiovascular Events   OTR   Organ Transplant Recipients   CAV   Cardiac Allograft Vasculopathy   HR   Hazard Ratios   OR   Odds Ratios   PRISMA   Preferred Reporting Items for Systematic Reviews and Meta-Analyses   RCT   Randomized Controlled Trials   TCIA   T-cell Immunity Assays   KTRs   Kidney Transplant Recipients   CHF   Congestive Heart Failure   PAD   Peripheral Arterial Disease   CVA   Cerebrovascular Accident   PE   Pulmonary Embolism   NSTEMI   Non-ST-Elevation Myocardial Infarction   STEMI   ST-Elevation Myocardial Infarction   MI   Myocardial Infarction   CAD   Coronary Artery Disease  

摘要： AbstractIntroductionDespite advancements in Cytomegalovirus (CMV) management, its impact on graft function, mortality, and cardiovascular (CV) health of organ transplant recipients (OTR) remains a significant concern. We investigated the association between CMV infection and CV events (CVE) in organ (other than heart) transplant recipients. MethodsWe conducted a comprehensive literature search in PubMed and EMBASE, including studies that reported on CMV infection or disease and post-transplantation CVE. Studies of heart transplant recipients were excluded. ResultsWe screened 3875 abstracts and 12 clinical studies were included in the final analysis, mainly in kidney and liver transplant recipients. A significant association was observed between CMV infection and an increased risk of CVE, with a pooled unadjusted hazard ratio (HR) of 1.99 (95% Confidence Intervals [CI] 1.45–2.73) for CMV infection and 1.59 (95% CI 1.21–2.10) for CMV disease. Pooled adjusted HR were 2.17 (95% CI 1.47–3.20) and 1.77 (95% CI 0.83–3.76), respectively. Heterogeneity was low (I 2 = 0%) for CMV infection, suggesting consistent association across studies, and moderate-to-high for CMVdisease (I 2 = 50% for unadjusted, 53% for adjusted HR). DiscussionWe found a significant association between CMV infection and CV risk in abdominal OTR, underscoring the importance of proactive CMV surveillance and early treatment. Future research should aim for more standardized methodologies to fully elucidate the relationship between CMV and CV outcomes, potentially informing novel preventive and therapeutic strategies that could benefit the CV health of OTR.

摘要： (no summary available)

关键词： 冲裁装置   凸轮轴   凸轮曲线   优化  

摘要： 针对DPB280型泡罩包装机冲裁装置凸轮轴易发生断裂的问题,对凸轮进行优化设计,进行了数据分析,构建了组合型加速度运动规律曲线,经试验测试,噪声降低、运动平稳,凸轮轴不再发生断裂,可以应用到更多有特殊要求的机械设备中。

关键词： CAD/CAM技术   汽车模具设计   制造策略  

摘要： 本研究主要关注基于CAD/CAM技术的汽车模具的设计与生产,并深入探索了这一技术在汽车模具产业中的实际应用和它的关键作用。研究突出设计准确性,精度控制,模具结构优化,材料选择,可制造性,经济性,创新性,技术融合,标准化与模块化等重要意义。同时本研究也给出了相应的制造策略,主要有先进制造技术应用,精益和智能制造技术融合,数控编程和加工路径优化,质量监控和管理,多学科协同设计和制造等。

关键词： 美育   CAD/CAE   美的设计   美的鉴赏  

摘要： 针对目前专业教育中美育的缺失,将美育融入课程教学显得尤为重要。本文通过回顾美育在大学教育中的发展历程,并结合《CAD/CAE技术及应用》课程的特点,提出“美的设计”理念。通过美的理念和欣赏,引导学生认识和创造美,将美学中的简洁之美、协调之美、细节之美和创新之美不断融入课程教学,帮助学生体验设计之美与艺术之美。这不仅提升了学生的审美鉴赏能力,还激发了他们的创造力和想象力,增强了他们的批判性思维,塑造了他们的健康的人格,从而培养他们正确的人生观和价值观。

关键词： 纺织品设计   KANO模型   陕西剪纸   抓髻娃娃”剪纸纹样   艺术特征  

摘要： 为探究陕西“抓髻娃娃”剪纸纹样在纺织品设计中的创新应用,提升用户对产品的满意程度,以图文互证的方式对“抓髻娃娃”剪纸纹样艺术特征进行梳理,进而结合当地民俗文化分析纹样内涵;基于KANO模型进行问卷设计,结合访谈所得16项用户需求指标进行问项设定并发放问卷;使用Cronbacha(克隆巴赫)系数对问卷结果进行信度分析,各项α系数皆高于0.8,问卷结果信度高;根据Better-Worse系数与二维象限散点图对需求要素进行优先级排序,获得必备属性(M)4项;期望属性(O)6项;魅力属性(A)4项;无差异属性(I)2项,最后将优化后的需求要素应用于现代纺织品创新设计中,以达到产品设计契合用户需求的目的,实现传统非遗文化的传承发展与创新转化。

关键词： A23187   Endothelium-dependent vasodilation   Microcirculation   Nitric oxide   Reactive oxygen species   HAAs   human adipose arterioles   CAD   coronary artery disease   L-NAME   N(omega)-nitro-l-arginine methyl ester   NO   nitric oxide   PGI 2   prostaglandins   H 2O 2   hydrogen peroxide   EDHF   endothelium-derived hyperpolarizing factor   ACh   acetylcholine   VSMC   vascular smooth muscle cells   ROS   reactive oxygen species   ONOO   peroxynitrite   eNOS   endothelial NO synthase   O 2   superoxide anion   ET-1   endothelin-1   ETC   electron transport chain  

摘要： The Ca²⁺ ionophore A23187 induces endothelium-dependent and non-receptor-mediated vasodilation in human adipose arterioles (HAAs). The purpose of this study was to determine the mechanism of A23187-induced dilation in HAAs from patients with and without coronary artery disease (CAD). HAAs were freshly isolated from adipose tissues obtained from non-CAD (n = 25) and CAD (n = 14) patients, and vascular reactivity was studied by videomicroscopy. No difference in baseline dose response to A23187 was observed between non-CAD and CAD subjects. However, acute (30 min) incubation with N(omega)-nitro-l-arginine methyl ester (L-NAME), NO synthase inhibitor strongly reduced A23187-induced dilation in non-CAD arterioles, while catalase, an H₂O₂ scavenger, largely abolished dilation in CAD. Surprising, prolonged (90 min) incubation with L-NAME restored A23187 response in non-CAD subjects, which was subsequently inhibited by catalase. The action of prolonged L-NAME exposure was not reversible after washing with Krebs while the effect of acute L-NAME exposure was largely reversible. To further determine the role of mitochondria-derived ROS in A23187-induced dilation, arterioles were treated with rotenone, an inhibitor of complex I of the electron transport chain. Rotenone abolished A23187 response in CAD patients and in non-CAD arterioles after prolonged L-NAME, but not in non-CAD controls. These data indicate that NO contributes to A23187-induced dilation in HAAs from non-CAD patients and H₂O₂ contributes to the dilation in CAD patients. Prolonged L-NAME exposure induces a NO-H₂O₂ switch in the mechanism of dilation in non-CAD subjects. Moreover, the effect of prolonged L-NAME exposure is not readily reversible, while the action of acute L-NAME exposure is reversible.

关键词： B++ splines   B-Rep CAD models   Conforming embedded isogeometric method   Isogeometric analysis   Trimmed CAD geometries  

摘要： Strong imposition of Dirichlet boundary conditions for immersed finite element methods or immersed isogeometric methods remains a challenge. To address this issue, this paper presents a 3D conforming embedded isogeometric method for Boundary-Represented (B-Rep) solid CAD models by generalizing our bivariate B++ splines to trivariate B++ Splines. The proposed method can convert a B-Rep model into a trivariate B++ spline solid patch with body-fitted boundary representation while retaining key features of B-rep models, such as sharp points, sharp edges, and holes. The basis functions of the trivariate B++ spline solid patch satisfy the Kronecker delta property, which implies that we can strongly impose Dirichlet boundary conditions on B-Rep models without the necessity of Nitsche's method. The presented method can be viewed as a parameterization method that inherits the advantages of volumetric parameterization methods in that the basis functions of a reconstructed geometry satisfy the Galerkin method. In addition, compared with T-splines, the proposed method does not generate the extraordinary point and can achieve optimal convergence rate. Several numerical examples are used to demonstrate the reliability of the presented method.

关键词： 机械CAD   机械制图   测量技术  

摘要： 本文重点研究机械CAD与机械制图及测量技术的融合运用,从制图设计过程、立体组合视图过程、剖视图设计过程、装配图设计过程四方面分析了机械CAD在机械制图中的应用方式,梳理了机械CAD分别与机械制图、测量技术的融合应用要点,以期为机械制图的转型升级提供有效指导。

关键词： 粉末冶金   双联凸轮   Deform模拟   浸铜   渗碳淬火  

摘要： 双联凸轮作为轻型电动牙钻机的主要传动零件,需具有轻便性及优良的力学性能。本文采用有限元Deform软件对不同模具结构方案下的压坯密度进行模拟分析,并基于Fe-Cr-Mo烧结硬化材料分别对常规烧结工艺、浸铜烧结工艺、常规烧结+渗碳淬火工艺以及浸铜烧结+渗碳淬火工艺四组试验进行研究,从合金成分、密度以及微观组织等角度分析不同工艺对力学性能的影响。最终选取“上二下三”的模具结构方案,采用浸铜烧结+渗碳淬火的组合工艺,成功制备出了高硬度、高耐磨性的双联凸轮。