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摘要： Cantilevered complete arch implant-supported prostheses are commonly fabricated from zirconia and more recently from strength gradient zirconia. Different polymer-based materials indicated for definitive fixed prostheses that could be used with additive or subtractive manufacturing have also been marketed recently. However, knowledge on the long-term fatigue behavior of cantilevered implant-supported prostheses made from these polymer-based materials and strength gradient zirconia is lacking.

关键词： 新工科   CAD   任务驱动   教学改革  

摘要： 结合国家“新工科”建设对高校教学质量与学生实践创新能力的要求,文章以电气工程及其自动化专业“电气工程CAD”课程教学为例,分析了课程特点与教学目标,教学过程中存在的问题。在此基础之上,提出了基于工程应用的任务驱动式“电气工程CAD”教学改革模式,详述了课程教学实施流程,并针对教学环节进行了详细的设计与说明,对课程考核方式进行了探讨,以期为“新工科”建设背景下工科类课程改革提供思路与借鉴。

关键词： QOD   Quality Outcomes Database   VAS   Visual Analogue Scale   ODI   Oswestry Disability Index   CAD   coronary artery disease   PVD   peripheral vascular disease   PRO   patient-reported outcome   MCID   minimally clinically important difference   MME   morphine milliequivalent   lumbar spine surgery   opioid use   patient reported outcomes   patient satisfaction   morphine milliequivalent  

摘要： Pain management surrounding lumbar spine surgery is a complex topic. Though some authors suggest that preoperative opioid use is a negative prognostic factor, its association with patient-reported outcomes and satisfaction after surgery remains controversial. We aimed to uncover the effect of preoperative opioid use on long-term outcomes using a national sample.

关键词： 电子纺织品   无线通信技术   智能穿戴   数据安全  

摘要： 在科技迅猛发展的当下,电子纺织品这一新兴智能材料横空出世,将纺织工艺与电子科技的长处进行了融合。文章针对电子纺织品中无线通信技术的运用展开深入探究,细致剖析了其运作机制、核心技术、遭遇的困境和在诸多领域的应用案例。借由对这些层面的研究,期望能为电子纺织品无线通信技术的后续发展给予理论依托与实践参照,助力其于智能穿戴、医疗保健、智能家居等方面达成广泛运用,带动多学科交融领域的革新与提升。

关键词： 冠状动脉磁共振成像   冠状动脉狭窄   诊断性能  

摘要： 目的:对比评估mDixon水脂分离序列与全心梯度回波序列(WHCA TFE)使用SPIR压脂技术3.0T非对比增强冠状动脉磁共振成像在可疑冠心病患者中的诊断性能。方法:前瞻性研究纳入烟台毓璜顶医院自2022年9月至2023年12月45名拟行冠状动脉造影术(CAG)的患者进行非对比增强冠状动脉磁共振成像检查(NCE-CMRA)。受试者分别接受mDixon序列与3D全心TFE序列使用SPIR技术的NCE-CMRA。两位放射科医生根据主观图像质量(评分1~5,5分代表最高图像质量评分)、血管可见长度、直径以及是否存在显著狭窄来独立评估冠状动脉;以CAG结果作为参考标准。使用配对t检验比较序列间血管长度、直径的差异,Wilcoxon检验比较各节段序列间主观图像质量评分的差异,McNemar检验对比序列间敏感性、准确性、特异性的差异,联合假设检验比较阳性预测值、阴性预测值的差异。结果:在45例可疑冠心病患者中,有40例(88.9%)成功采集了全心CMRA图像并被纳入分析,3.0T mDixon序列的总体图像质量评分为(3.9±0.9),3.0T WHCA TFE序列使用SPIR技术的总体平均图像质量评分为(3.7±0.9)。相比于WHCA TFE序列使用SPIR技术,mDixon序列在基于节段水平显示出更高的敏感度(78.5%比66.1%)、特异度(96.5%比93.8%)、准确性(91.7%比86.6%)、阳性预测值(88.6%比78.9%)以及阴性预测值(93.4%比88.7%),在基于血管水平显示出更高的敏感度(89.4%比81.6%)和准确性(89.1%比83.3%)。结论:相较于3.0T WHCA TFE序列使用SPIR技术,mDixon序列NCE-CMRA具有更可靠的诊断效能。

关键词： 机织物   过滤   拉伸性能   透气性   孔径分布  

摘要： 为进一步探究不同组织结构对机织过滤布过滤性能的影响,对纱线原料相同、总紧度相近的平纹和破斜纹织物的拉伸、透气、孔径分布等性能进行测试分析。结果表明:紧度相近的平纹和破斜纹组织织物,平纹织物相对密度高,织造难度较大;破斜纹织物断裂强力优于平纹织物,可应用于较高压力的过滤场景;平纹织物透气性和孔径较小,适用于高精度过滤场合。

关键词： 自动炮   凸轮   优化设计   简谐运动   摆线运动  

摘要： 针对某外能源驱动自动炮在推弹动作到位时会偶发弹药轴向解体而造成故障的问题,通过对实现推弹动作的推弹凸轮曲线进行分析,确定了运用摆线运动代替简谐运动的曲线优化思路。建立了摆线过渡段曲线通用方程并由自动炮循环图作为结构参数边界条件,经结构参数寻优获得凸轮曲线方程。经仿真对比,优化后较优化前的凸轮机构从动件运动加速度值整体有明显下降;完成了实物试验对比验证,将优化前后的凸轮实物分别装机进行模拟射击试验测试,测试结果与优化结果相符;后再经初步的实弹射击试验,弹药轴向解体现象暂未再次出现。优化结果证明了采用摆线运动曲线作为凸轮曲线过渡段可以有效地降低被凸轮从动部件驱动的弹药的受力状态。

关键词： 气体氮碳共渗   保护气氛   淬火   复合处理  

摘要： 对GCr15钢凸轮分别进行气体氮碳共渗、保护气氛炉中油淬、气体氮碳共渗+保护气氛炉中油淬的复合处理,然后检测凸轮表层的氮碳含量、显微组织、表面硬度及硬化层深度。结果表明:经580℃气体氮碳共渗6h的凸轮表层形成了约20μm厚的化合物层,其含氮量约为0.2%,扩散层深约650μm;经复合处理的凸轮表层氮化合物完全分解,扩散层深约750μm,氮的固溶强化使扩散层硬度比淬火态硬度约高30HV0.3,但产生的孔隙及表面氧化和脱碳导致表面硬度下降。

关键词： CAD CAM   Endocrowns   Failure mode   Fracture resistance   Monolith Zirconia   Pulpal extension depth  

摘要： BackgroundPulpal extension depth (PED) is critical for endocrowns restored teeth stability and longevity. There is a conflicting result regarding the minimum PED needed for the success of endocrowns. The aim of the current study was to compare Fracture resistance, failure mode, and restorability of CAD-CAM zirconia endocrowns with different pulpal extension depths bonded to maxillary molars.Materials and methodsForty maxillary 1st molars were selected, decoronated, and randomly divided into 4 main groups (n = 10) according to the PED measured from the pulpal floor to the occlusal end of the wall height into;group D2, PED was 2 mm, group D3, PED was 3 mm, group D4, PED was 4 mm, group D5 PED was 5 mm. Teeth were prepared and secured in resin dies with pseudo periodontal ligament. Specimens from all groups were individually scanned using an intra oral digital scanner. Monolithic zirconia endocrowns were constructed and bonded to their corresponding. Following thermal cycling, each specimen was axially loaded in a universal testing machine at a 0.5 mm/min crosshead speed. Failure modes were inspected, and restorability of specimens was recorded. Data was collected, tabulated, and statistically analyzed.ResultsDescriptive statistics displayed higher mean value of the D2 group (3657 1673.8 N) followed by the D3 group (3009.3 853.5 N then the D4 group (2087.3 413.9 N) and finally the D5 group (1972.7 +/- 330.4 N). At a 95% confidence level, one-way analysis of variance (ANOVA) revealed significant differences between tested groups. (P = 0.014). Regarding failure mode, D2 recorded 100% restorable failures, followed by D3 (90%) and D4 (60% while the least was D5 (50%).ConclusionsEndocrowns with 2 mm PED recorded the highest fracture resistance and the highest restorable failure modes. Endocrowns with 5 mm PED recorded the lowest fracture resistance and the lowest restorable failure modes. Tall walls should be shortened during the preparation of endocrowns in maxillary molar

关键词： 研发型企业   晓梦   家纺产品   融合技术   纺织品   睡眠   发展历程  

摘要： 2024年,市场浪潮起伏,对于以开发草本系列家纺产品为主的研发型企业—成都晓梦纺织品有限公司而言,这一年的发展历程充满了挑战与突破,也为未来的前行积累了宝贵经验。2025年,晓梦将如何以智能化新品在睡眠市场勇立潮头?破局2024:困境中谋变,突破中前行成都晓梦多年来始终保持着良性增长的态势,在草本产品领域默默耕耘,首创草本香疗家纺系列,首创阶段理疗枕系列;拥有独家研发的草本填材全物理灭虫杀菌系统和独家研发的草本香疗融合技术,致力于将传统草本智慧与现代科技相融合,为消费者打造高品质的产品,是国内以苦荞草本枕为核心的大健康家纺家居引领者。