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关键词： Percutaneous coronary intervention   Chronic kidney disease   Intravascular imaging   Contrast-induced nephropathy   Coronary artery disease, atherosclerosis   AKI   acute kidney injury   CABG   coronary artery bypass grafting   CAD   coronary artery disease   CFR   coronary flow reserve   CIN   contrast induced nephropathy   CKD   chronic kidney disease   CTA   computed tomography angiography   CVD   cardiovascular disease   ECG   electrocardiogram   ESRD   end stage renal disease   GFR   glomerular filtration rate   LVEDP   left ventricular end-diastolic pressure   MI   myocardial infarction   NSTEMI   non ST elevation myocardial infarction   PCKS9   Proprotein convertase subtilisin/kexin type 9   PET   Positron emission tomography   RRT   renal replacement therapy   SPECT   single-photon emission computed tomography   UCLA   ultra-low contrast angiography  

摘要： Coronary artery disease (CAD) is the leading cause of mortality among patients with chronic kidney disease (CKD), presenting unique challenges in diagnosis and management. Advanced CKD patients often present with atypical symptoms, and conventional diagnostic and interventional approaches carry risks, including contrast-induced nephropathy and the potential need for renal replacement therapy. These risks have led to the phenomenon of “renalism,” where necessary procedures may be deferred due to concerns over renal injury. Emerging techniques, such as ultra-low contrast angiography (ULCA) and zero-contrast percutaneous coronary intervention (PCI), offer promising solutions by minimizing or eliminating contrast exposure. This review discusses the clinical presentation of CAD in CKD patients, limitations of traditional diagnostic approaches, and the challenges in managing these high-risk patients. It also provides an overview of ULCA and zero-contrast PCI techniques, which have shown both safety and feasibility even in complex cases. As these techniques continue to evolve, zero-contrast PCI holds the potential to become an essential component of revascularization strategies for high-risk CKD patients, enhancing procedural safety while maintaining therapeutic efficacy.

关键词： 新工科   课程思政   教学改革   生态纺织品检测技术  

摘要： 立德树人是教育的根本任务,思政教育是立德树人的重要途径和手段,有助于学生成长成才。将课程思政与专业课程融合,是提升教育质量、培养高素质人才的重要路径,探讨新工科背景下课程思政的重要性,梳理“生态纺织品检测技术”课程中的思政元素,分析课程融入思政教育的具体策略。旨在将课程思政与专业课程有机融合,为今后此类课程思政建设提供一定参考。

关键词： CAD/CAM   氧化锆桩核   前牙缺损   咀嚼功能  

摘要： 目的 探究CAD/CAM氧化锆桩核对前牙缺损患者牙齿机械及功能性能的影响.方法 选取2023年1月-2025年1月江门市口腔医院收治的80例前牙缺损患者作为研究对象,按随机数字表法将其分为对照组与观察组,各40例.对照组采用传统金属桩核修复,观察组采用CAD/CAM氧化锆桩核修复,比较两组美学效果、牙齿机械及功能性能及工艺质量.结果 观察组修复后颜色匹配度、形态自然度、边缘适合性及表面光泽度均优于对照组(P＜0.05);观察组修复后抗折强度、咀嚼效率及表面硬度均高于对照组(P＜0.05);观察组修复后加工精度、表面光洁度及烧结尺寸稳定性均优于对照组(P＜0.05).结论 CAD/CAM氧化锆桩核不仅能满足前牙缺损患者对美学效果的高要求,还能有效恢复牙齿机械及功能性能,其数字化制作工艺更确保了修复体的精确性与长期稳定性.

关键词： Coputed tomorgaphy coronary angiography   Calcific coronary artery disease   Chronic coronary syndrome  

摘要： Coronary Artery Disease-Reporting and Data System (CAD-RADS) standardises Computed Tomography Coronary Angiography (CTCA) reporting. Coronary calcification can overestimate stenosis. We hypothesized where CADRADS category is assigned due to predominantly calcified maximal stenosis (Ca+ the CTCA-derived Fractional Flow Reserve (FFRCT) would be lower compared to predominantly non-calcified maximal stenoses (Ca-) of the same CAD-RADS category. Consecutive patients undergoing routine clinical CTCA (September 2018 to May 2020) with >= 1 stenosis >= 25% with FFRCT correlation were included. CTCA's were subdivided into Ca+ and Ca-. FFRCT was measured in the left anterior descending (LAD left circumflex (LCx) and right coronary artery (RCA). Potentially flow-limiting classified as FFRCT <= 0.8. A subset had Invasive Coronary Angiography (ICA). 561 patients screened, 320 included (60% men, 69 +/- 10 years). Ca+ in 51%, 69% and 50% of CAD-RADS 2, 3 and 4 respectively. There was no difference in the prevalence of FFRCT <= 0.8 between Ca+ and Ca- stenoses for each CAD-RADS categories. No difference was demonstrated in the median maximal stenoses FFRCT or end-vessel FFRCT within CAD-RADS 2 and 4. CAD-RADS 3 Ca+ had a lower FFRCT (maximal stenosis p= .02, end-vessel p= .005) vs Ca-. No difference in the prevalence of obstructive disease at ICA between predominantly Ca+ and Ca- for any CAD-RADS category. There was no difference in median FFRCT values or rate of obstructive disease at ICA between Ca+ and Castenosis in both CAD-RADS 2 and 4. Ca+ CAD-RADS 3 was suggestive of an underestimation based on FFRCT but not corroborated at ICA.

摘要： Airway epithelial cells serve critical protective roles as biochemical and physical barriers between the lung and the external environment (1). Environmental factors, such as those linked to climate change, pose a greater threat to epithelial barrier in the lung (2). Epithelial integrity is maintained by tight junctions and adherens junctions (AJs). During the progression of conditions such as chronic obstructive pulmonary disease (COPD) and asthma, these junctions are compromised and epithelial barrier is impaired. In severe asthma, impaired barrier function increases susceptibility to external insults and increased airway infiltration of inflammatory cells. Additionally, impaired barrier integrity is accompanied by compromised biochemical activities of airway epithelial cells, including dysregulated antimicrobial and antiviral activities and increased secretion of inflammatory cytokines (1). AJs are critical for maintaining epithelial integrity and barrier function. They form strong cell adhesions through the transmembrane protein E-cadherin. Its extracellular domain interacts homotypically with E-cadherins on adjacent cells to maintain AJs, whereas the cytoplasmic domain binds to α- and β-catenins, regulating intracellular signals, and F-actin to control cytoskeletal organization and mechanical force generation (3). Therefore, E-cadherin regulates a range of cellular processes, including adhesion, morphogenesis, differentiation, wound healing, and force transmission. Its loss compromises cellular integrity and architecture, increasing epithelial barrier permeability. Traditionally, the loss of E-cadherin is a hallmark of epithelial-to-mesenchymal transition and is considered a result of transcriptional and epigenetic regulation (2). However, recent studies indicate that E-cadherin can be removed from epithelial cells through ectodomain shedding by ADAM proteases (4, 5) and exosome release (6), potentially independent of epithelial-to-mesenchymal transition. Solub

关键词： In-pipe robot   Three-lobed cam   Cam-operated   Dynamic model   Simulation  

摘要： This paper presented a novel mechanism and dynamic model of Cam-operated In-Pipe Robot (CIPR) a proof of concept. The CIPR would be useful for in-pipe inspection for detecting the defects like cracks, surface wear, damage, scaling etc. Based on the dynamic model, a gripping mechanism actuated by three-lobed cam has been developed. A special three-lobed cam provides sufficient frictional force maneuver and stop the robot inside the pipe of diameter 250 mm during inspection and cleaning task. proposed dynamic model determines the frictional force and torque required to move the robot. specially designed three-lobed cam makes the overall mechanism compact as compared to available in pipe robots. A single cam is adequate to exert uniform gripping force between the contact surface of the wheel and the inner surface of the pipe. In the present work, solid model of the CIPR is used to analyze and simulate the dynamics of the CIPR using ADAMS. The model is tested in simulated environment for vertical motion to determine the frictional force and wheel torque characteristics. The simulation results are in line with the analytical results. Further, the prototype is successfully maneuvering inside the pipe for different orientations.

关键词： rib fractures   machine learning   CT images   predictive modeling   Grad-CAM visualization  

摘要： AIM: This study aimed to develop a reliable and efficient system for predicting and locating rib fractures in medical images using an ensemble of convolutional neural networks (CNNs). METHODS: We employed five CNN architectures-Visual Geometry Group Network 16 (VGG16 Densely Connected Convolutional Network 169 (DenseNet169 Inception Version 4 (Inception V4 Efficient Network B7 (EfficientNet-B7 and Residual Network Next 50 layers (ResNeXt-50)-trained on a dataset of 840 grayscale computed tomography (CT) scan images in.jpg format collected from 42 patients at a local hospital. The images were categorized into two groups representing healed and fresh fractures. The ensemble model was designed to improve predictive accuracy and robustness, utilizing techniques like gradient -weighted class activation mapping (Grad -CAM) for visualization of fracture locations. RESULTS: The ensemble model achieved an accuracy of 0.96, area under the curve (AUC) of 0.97, recall of 0.97, and F1 score of 0.96. Grad -CAM visualizations could effectively locate rib fractures, providing crucial assistance in diagnostics. CONCLUSIONS: The ensemble model demonstrates high accuracy and robustness in fracture detection, underscoring its potential for enhancing diagnostic processes in clinical settings. Despite limitations such as the small dataset size and lack of diverse demographic representation, the results are promising for future clinical application.

摘要： Objective: This study aimed to assess the fracture resistance of chairside computer assisted design and computer assisted manufacturing (CAD-CAM) lithium disilicate partial and full-coverage crowns and veneers for maxillary canines. Methods and Materials: Forty-eight restorations for maxillary right canines (12 per group) were designed as follows 1) partial crown with finish line in the upper middle third;(2) partial crown with finish line in the lower middle third;(3) traditional labial veneer;and (4) traditional full- coverage crown. Restorations were fabricated out of lithium disilicate (Amber Mill, Hassbio) using a chairside CAD-CAM system (Cerec Dentsply Sirona). Partial and full crowns and veneers were treated with a primer system (Monobond Plus, Ivoclar Vivadent) and cemented using dual-cure resin cement (Variolink Esthetic, Ivoclar Vivadent) and cemented to printed resin dies. Subsequently, the restorations were subjected to 10,000 thermocycles between 5 degrees C and 55 degrees C with a dwell time of 30 seconds. The restorations were then loaded axially on the incisal edge in compression to fracture with a flat indenter. Results: Full-coverage crowns displayed the highest fracture resistance (809 +/- 28.57 N) followed by partial crowns with finish line in lower third (649 +/- 21.74 N) and crowns with finish line in upper third (421 +/- 17.46 N). Veneers displayed the lowest fracture resistance values (259 +/- 15.69 N). Conclusions: The fracture resistance of partial and full-coverage crowns and veneers was significantly influenced by the design. Full coverage crowns displayed the highest fracture resistance and partial crowns showed higher fracture resistance than traditional veneers.

关键词： Nodule detection   Lung cancer   Deep learning   Neural networks   CAD  

摘要： Lung nodule detection is clinically crucial but challenging and time-consuming. The development of automated segmentation approaches could be helpful. To assess the capability of deep learning methods for lung diagnosis, this paper compares recent deep learning models and evaluates their performance. We implemented several preprocessing steps, including windowing, thresholding, and resizing, to improve the image quality, adjust the image dimension suitable for the network, and focus on specific areas of interest within an image. The evaluation was conducted on the Lung Image Database Consortium (LIDC) dataset using Dice similarity coefficient (DSC) and Hausdorff distance (HD) metrics with model complexity parameters for a multifaceted comparison of the models. The experiments showed that the highest accuracy among the five chosen models (97.80% DSC and 1.29 HD) was reached by the Connected-UNets model, which also has the highest computational complexity. In this paper, we quantitatively evaluated and compared 5 deep learning models namely Salient Attention UNet, Connected-UNets, DDANet, UTNet, and EdgeNeXt. The evidence-based overview of current deep learning achievements for the clinical community investigated in this study can be useful to the research community in developing a new model and, thus, designing computer-aided detection and diagnosis (CAD) systems.

关键词： Non-circular fit   equivalent interference   flexible bearing   cam   sequential assembling and loading simulation   harmonic reducer  

摘要： The flexible bearing is usually connected to the cam with an interference fit in harmonic reducers. Studies show that interference fit can cause changes in the structural parameters of the bearing and lead to changes in the service performance of the bearing and its supporting system. This paper proposes a general simulation method to investigate the influence of interference fit in harmonic reducers with the concept of the equivalent interference for non-circular fit between the flexible bearing and cam. Then, the four steps based on the sequential assembling and loading process are designed to ensure assembly concentricity and simulation convergence. The analysis results indicate that appropriately increasing the equivalent interference can improve the service life of the flexspline without degrading the meshing performance and, at the same time, increase the number of loaded balls to make the operation of the harmonic reducer more stable. Moreover, an optimal equivalent interference can be designed to ensure the harmonic reducer operates at its best, where the number of loaded balls and the maximum Mises stress of the inner ring appear inflection point, and the number of meshing tooth pairs reaches the maximum.