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摘要： Une femme de 58 ans a été adressée pour des douleurs au poignet droit, avec suspicion de fracture de fatigue de la styloïde radiale. Une scintigraphie osseuse au 99mTc-HDP a été réalisée à l’aide de la caméra CZT StarGuide. Les images TEMP/TDM au temps précoce ont mis en évidence une hyperhémie intense le long du premier compartiment extenseur du poignet droit, évoquant une ténosynovite de De Quervain, tandis que les images TEMP/TDM au temps tardif ne montraient qu’une arthrose du pouce droit. L’échographie a mis en évidence un épaississement tendineux œdémateux, une augmentation du liquide péritendineux et une hyperhémie du premier compartiment extenseur du poignet droit, évocateurs d’une ténosynovite de De Quervain. La ténosynovite de De Quervain est une affection douloureuse fréquente liée à des mouvements répétitifs, touchant principalement les femmes, avec une prévalence estimée à 1,3 %. Elle est classiquement décrite comme un épaississement du rétinaculum des extenseurs, liée à une inflammation des tendons de l’extensor pollicis brevis et de l’abductor pollicis longus au niveau du premier compartiment extenseur du poignet. Le diagnostic est généralement clinique, basé sur une douleur localisée associée à un test de Finkelstein positif. Les examens d’imagerie conventionnelle — échographie et IRM — sont couramment utilisés pour confirmer le diagnostic. Bien que la ténosynovite de De Quervain ait déjà été décrite en scintigraphie osseuse planaire, la littérature reste limitée concernant l’intérêt de la TEMP/TDM au temps précoce dans les tendinites du poignet. Une étude de Cuvilliers et al. a montré que l’ajout d’un TEMP/TDM au temps précoce à la scintigraphie osseuse triphasique conventionnelle modifiait la conclusion diagnostique chez un quart des patients présentant des douleurs des membres inférieurs, en révélant significativement plus de tendinites qu’en imagerie planaire. À notre connaissance, aucune étude n’a encore évalué les performances de la TEMP/TDM ut

关键词： artificial intelligence   liver imaging   AI in liver imaging   LI-RADS   2D   two-dimensional   3D   three dimensional   AI   Artificial intelligence   AUROC   area under the receiver operating characteristic curve   AUC   area under the curve   BD-LSTM   bidirectional long short-term memory   CAD   computer-aided detection/diagnosis   C index   concordance index   CEUS   contrast enhanced US   CLAIM   Checklist for Artificial Intelligence in Medical Imaging   CNN   convolutional neural network   CT   computed tomography   DCNN   deep convolutional neural network   DL   deep learning   DSC   dice similarity coefficient   DWT   discrete wavelet transform   EHR   electronic health record   FAD   food and drug administration   FLL   focal liver lesion   GDPR   General Data Protection Regulation   HCC   hepatocellular carcinoma   HIPPA   Health Insurance Portability and Accountability   HRI   hepatorenal index   IT   information technology   LI-RADS   Liver Imaging Reporting and Data System   LSN   liver surface nodularity   LSTM   long short-term memory   MASLD   metabolic dysfunction–associated steatotic liver disease   METAVIR   meta-analysis of histological data in viral hepatitis   MR   magnetic resonance   MRI   magnetic resonance imaging   MRI-PDFF   magnetic resonance imaging proton density fat fraction   ML   machine learning   MVI   microvascular invasion   NLP   natural-language processing   PACS   picture archiving and communication system   RECISR   response evaluation criteria in solid tumors   RF   radiofrequency   RNN   recurrent neural network   SSL   Self-Supervised Learning   SVM   support vector machine   SWE   shear wave elastography   TACE   transarterial chemoembolization   US   ultrasound  

摘要： Artificial intelligence (AI) has emerged as a transformative tool in liver imaging, offering enhanced diagnostic accuracy, efficiency, and reproducibility. The integration of machine learning and deep learning algorithms into radiological workflows has shown significant promise across a wide range of liver diseases. Key applications include automated liver segmentation on computed tomography (CT) and magnetic resonance imaging (MRI), enabling accurate liver volumetry and lesion localization. In metabolic dysfunction–associated steatotic liver disease, AI facilitates the detection and quantification of hepatic steatosis using advanced image analysis on ultrasound, CT, and MRI, providing a non-invasive alternative to biopsy. AI algorithms also demonstrate strong performance in detecting, classifying, and characterizing focal liver lesions such as hemangioma, focal nodular hyperplasia, hepatocellular carcinoma (HCC), and metastases, improving lesion conspicuity, standardizing reporting through LI-RADS, and reducing inter-observer variability. Beyond diagnosis, AI is increasingly applied for risk stratification and prognostication in HCC, integrating imaging, clinical, and laboratory data to predict tumor development, aggressiveness, treatment response, and survival outcomes. Despite these advances, the clinical implementation of AI in liver imaging faces notable challenges such as the need for data harmonization across scanners and institutions, rigorous validation in diverse patient populations, regulatory approval, and ethical considerations surrounding patient privacy, algorithmic bias, and transparency. Addressing these limitations through robust research, multi-center studies, and carefully designed clinical integration strategies is essential to safely and effectively harness AI’s potential. With continued development and validation, AI has the capacity to enhance diagnostic workflows, enable precision medicine, and ultimately improve patient outcomes in hepatolo

关键词： 凸轮挺杆   仿真   表面改性   减摩抗磨   摩擦系数   润滑油添加剂  

摘要： 首先按时间顺序对凸轮挺杆材料的研究与应用进行了梳理,发现不同时期该部件的材料应用侧重点有所不同。其次,简要介绍了仿真模拟技术在凸轮挺杆减摩改性中的应用,并结合仿真结果分析了其减摩机理。此外,复合表面改性能够实现优势互补,从而有效改善摩擦学性能。相比之下,单一表面改性虽能提升减摩性能,但往往存在缺陷。诸如,表面织构在高载荷下易损坏,而部分固体润滑涂层则存在易脱落等问题。若将表面织构与离子注入或涂层技术相结合,则能在提高摩擦学性能的同时,有效减少涂层的脱落。这为延长凸轮挺杆的使用寿命提供了新思路。润滑油添加剂在内燃机中的应用,可改善运动部件的摩擦状况。在合理范围内,较高的润滑油黏度有助于形成更厚的油膜,从而更有效地降低表面摩擦系数。新兴的绿色环保型添加剂则能进一步减少有害气体的排放,这为适应新时代的绿色环保政策提供了解决方案。最后,对未来内燃机凸轮挺杆材料的表面减摩抗磨改性研究,以及润滑油添加剂的发展趋势与挑战进行了展望。

关键词： 轮辐扩展   凸轮机构   参数计算   运动仿真   越障表现  

摘要： 针对轮式移动机器人越障能力与车轮尺寸之间的矛盾属性,设计了一种基于凸轮机构传动的可扩展车轮。首先,在对可扩展车轮运动步态解析的基础上,完成了主要参数和几何尺寸的计算;其次,运用Soildworks建立了可扩展车轮三维实体模型,并基于Adams构建了台阶攀爬运动模型;最后,为验证攀爬运动表现,进行了连续台阶攀爬对比仿真实验。结果表明:轮辐扩展后,机器人攀爬连续台阶的效率比未扩展前高出20%,同时质心加速度幅值变化明显更小,设计的可扩展车轮可以高效稳定地完成越障任务。

关键词： generative design   CAD   design automation   imbalanced data   computer-aided design   machine learning  

摘要： Computer-aided design (CAD) programs, structured as parametric sequences of commands that compile into precise 3D geometries, are fundamental to accurate and efficient engineering design processes. Generating these programs from nonparametric data such as point clouds and meshes remains a crucial yet challenging task, typically requiring extensive manual intervention. Current deep generative models aimed at automating CAD generation are significantly limited by imbalanced and insufficiently large datasets, particularly those lacking representation for complex CAD programs. To address this, we introduce GenCAD-3D, a multimodal generative framework utilizing contrastive learning for aligning latent embeddings between CAD and geometric encoders, combined with latent diffusion models for CAD sequence generation and retrieval. In addition, we present SynthBal, a synthetic data augmentation strategy specifically designed to balance and expand datasets, notably enhancing representation of complex CAD geometries. Our experiments show that SynthBal significantly boosts reconstruction accuracy, reduces the generation of invalid CAD models, and markedly improves performance on high-complexity geometries, surpassing existing benchmarks. These advancements hold substantial implications for streamlining reverse engineering and enhancing automation in engineering design. We will publicly release our datasets and code, including a set of 51 3D-printed and laser-scanned parts on our project site.

关键词： NX   CAM   数控车削加工   刀轨设置   后处理器  

摘要： 计算机辅助制造(CAM)凭借高效、数字化特征,在智能制造领域占据举足轻重的地位。以典型螺纹轴零件为研究对象,通过NX2312软件完成其CAM全流程,对NX数控车削编程模块展开全面深入解析。研究重点涵盖四层级几何体构建、车削刀轨工序设置、程序后处理器优化等关键内容。同时,系统阐述了数控车削加工工艺在NX-CAM中的实现路径,该技术策略可有效提升编程效率。经仿真加工与试制验证,所设计的工艺方案、刀轨工序及优化后的后处理器可加工出合格零件,且各项指标满足机床性能要求,为NX软件在数控车削加工中的工程应用提供了技术支撑。

关键词： 3D-print   CAD/CAM   Color stability   Dental material   Discoloration   Resin composite  

摘要： This study aimed to evaluate the color stability of four three-dimensionally-printed (3D) resin composites, and compare them with nine other commonly used subtractive computer-aided designing/computer-aided manufacturing (CAD/CAM) materials and resin composites for direct restoration.

关键词： BIM   CAD-to-BIM   Dynamo   Precast concrete   Semantic naming convention  

摘要： The manual conversion of 2D CAD drawings to 3D BIM objects for Precast Concrete (PC) components is a time-consuming, error-prone bottleneck that hinders project efficiency. Existing automation studies have struggled with the complex, non-standard geometries typical of PC components. This paper presents a framework that automates BIM generation using a Semantic Naming Convention (SNC) to encode design information into 2D CAD attributes. Developed in the Dynamo visual programming environment, the system automatically creates fabrication-level BIM objects for PC columns, beams, and slabs. The framework's versatility was validated by successfully processing 100% of production drawings from three different manufacturers. A Charrette test showed the automated approach reduced modeling time by an average of 78.9%, improved model accuracy by 12.3, and cut human errors by over 90% compared to manual methods. This framework provides a practical solution to enhance productivity and model quality in the PC construction sector.

关键词： 纺织品   洗涤条件   外观质量  

摘要： 在穿着和使用后,纺织品通常需要通过水洗或干洗来进行清洁。而经过水洗或干洗后,纺织品可能会出现一些外观上的变化,如色变、沾色、印花脱落、接缝开裂、起毛起球、附件破损、填充不均匀等现象。这些变化会影响纺织品的服用外观和使用性能,可能导致消费者投诉。本文主要阐述了纺织品进行外观测试时所需的测试条件、相关的评价要求与评价内容,列举了常见的外观质量问题并进行简要分析。

关键词： cholecystitis   end-stage liver disease   ERCP   gall bladder drainage   AIH   Autoimmune hepatitis   CAD   Coronary artery disease   CC   Complicated cholecystitis   CI   Confidence interval   CTP   Child–Turcotte–Pugh   DCMP   Dilated cardiomyopathy   ERCP   Endoscopic retrograde cholangiopancreatography   ETGS   Endoscopic transpapillary GB stenting   EUS   Endoscopic ultrasound   GB   gall bladder   HR   Hazard ratio   HVOTO   Hepatic venous outflow tract obstruction   MASLD   Metabolic dysfunction-associated steatotic liver disease   MELD   Model for end-stage liver disease   PCLD   Polycystic liver disease   PSC   Primary sclerosing cholangitis  

摘要： Patients with cholecystitis and underlying cirrhosis represent a high-risk group for surgical intervention. In patients otherwise meriting an endoscopic retrograde cholangiopancreatography (ERCP), endoscopic transpapillary gallbladder stenting (ETGS) can serve as a bridge to cholecystectomy while awaiting liver transplant or provide long-term gallbladder (GB) drainage in those who are not surgical candidates. We evaluated the technical feasibility, clinical outcomes and safety of ETGS for complicated cholecystitis in patients with cirrhosis and high surgical risk.