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关键词： CAD/CAM materials   finite element analysis (FEA)   flexural strength   inlay restoration   modulus of elasticity   nanoindentation   von Mises stress  

摘要： Background: This study aimed to investigate the biomechanical behavior of conservative inlay restorations fabricated from different CAD/CAM materials by combining experimental flexural strength testing with finite element analysis. Methods: Five CAD/CAM materials were evaluated: feldspathic ceramic (Cerec Blocs), leucite-reinforced ceramic (IPS Empress CAD), resin nano-ceramic (Lava Ultimate), polymer-infiltrated ceramic network (VITA Enamic), and lithium disilicate ceramic (IPS *** CAD). Young's modulus and Poisson's ratio were experimentally determined using three-point bending and nanoindentation tests and used as inputs for 3D FEA. Von Mises (VM) stress distributions within the inlays were analyzed under simulated occlusal loading. Results: Maximum VM stresses showed an inverse relationship with material elasticity. IPS *** CAD exhibited the highest maximum VM stress (45.571 MPa), whereas the resin nano-ceramic showed the lowest (25.419 MPa). Despite higher stress concentrations in high-modulus ceramics, VM values for all materials remained well below their FS limits. Conclusions: All materials demonstrated adequate mechanical stability under physiological loading. Lithium disilicate showed a comparatively larger margin between stress levels and flexural strength, while lower-modulus materials tended to promote greater stress transfer to supporting structures.

关键词： 晋商大院   砖雕艺术   视觉符号   纺织品设计   文化创新  

摘要： 晋商大院砖雕是明清晋商文化的重要物质载体。本研究将砖雕视觉符号视为一个完整的“文化IP”进行解码,通过文献与实地考察,突破传统纹样复制局限,探究砖雕视觉符号在现代纺织品设计中的创新应用路径,以期为增强现代纺织品独特的文化内涵与艺术魅力、推动地域文化的创新性发展提供参考借鉴。

关键词： pulmonary arterial hypertension   scleroderma   AUC   area under the curve   CAD   coronary artery disease   IQR   interquartile range   JHPHP   Johns Hopkins Pulmonary Hypertension Program   JHSC   Johns Hopkins Scleroderma Center   mPAP   mean pulmonary arterial pressure   PA   pulmonary arterial   PAH   pulmonary arterial hypertension   PH   pulmonary hypertension   PVR   pulmonary vascular resistance   RHC   right heart catheterization   ROC   receiver operating characteristic   RV   right ventricular   SSc   systemic sclerosis   SSc-PAH   SSc with pulmonary arterial hypertension   SSc-PH   systemic sclerosis-associated pulmonary hypertension   UA   uric acid   XOR   xanthine oxidoreductase  

摘要： Preclinical studies have demonstrated the importance of xanthine oxidoreductase (XOR) in the pathobiology of pulmonary hypertension (PH) through generation of uric acid, reactive oxygen species, and vascular endothelial dysfunction.

关键词： Computer-aided manufacturing (CAM)   Polygon   Tool path generation   Machinability   Cutting force prediction  

摘要： This study proposes a unified two-dimensional (2D) polygon-based computer-aided manufacturing (CAM) framework that enables tool path generation, machinability evaluation, material removal simulation, and cutting-force prediction within a single computational environment. The proposed method represents three-dimensional geometries as aggregates of orthogonal 2D polygon sets, obtained by slicing the model in the $xy$-, $yz$-, and $zx$-parallel planes and superposing the three polygonal datasets. A novel convolutional offsetting algorithm is developed to perform three-dimensional inflation and shrinkage by incorporating adjacent cross-sectional relationships, thereby achieving accurate 3D offsets independent of the slicing orientation. The inflated 2D polygons are directly utilized to generate contour and scanning tool paths, and sequential inflation–shrinkage analysis enables visualization of unmachinable regions for tool accessibility evaluation. Furthermore, the framework integrates an instantaneous cutting force model that accurately predicts the cutting force waveform by detecting intersections between the cutting edge points and 2D polygon aggregations. The system is experimentally validated via ball-end milling. The results demonstrate that tool paths can be generated in under one minute using only a CPU. Furthermore, the simulated cutting forces closely align with experimental measurements. These findings demonstrate that the proposed 2D polygon-based framework provides an efficient and extensible foundation for integrating mechanical simulation and tool-path generation.

关键词： artificial intelligence   CAD-RADS score   calcium scoring   coronary CTA   prognosis   AI-QCT   artificial intelligence–guided quantitative coronary computed tomography angiography   AUC   area under the curve   CACS   coronary artery calcium score   CAD   coronary artery disease   CT   computed tomography   CTA   computed tomography angiography   LAP   low attenuation plaque   MACE   major adverse cardiac events   MI   myocardial infarction   NCPV   noncalcified plaque volume   NRI   net reclassification index   PAV   percent atheroma volume  

摘要： The severity and extent of whole heart coronary plaque volume and stenosis can be reliably measured by artificial intelligence–guided quantitative coronary computed tomography angiography (AI-QCT). Limited data are available on the potential incremental prognostic value compared with currently recommended qualitative coronary computed tomography angiography (CTA) reads and the coronary artery calcium score (CACS).

关键词： 急性胰腺炎   直方图分析   磁共振成像   大黄素   微循环   大鼠  

摘要： 目的探究基于多参数磁共振成像(magnetic resonance imaging,MRI)构建急性胰腺炎(acute pancreatitis,AP)大鼠微循环障碍及炎症负荷的程度量化评估体系,验证对比增强比(contrast enhancement ratio,CR)及直方图(histogram)参数在大鼠胰腺损伤评价中的价值,并探索大黄素(emodin)在活体状态下的潜在保护作用。材料与方法共纳入45只Sprague-Dawley(SD)大鼠,分为AP组、大黄素干预(emodin treated,ET)组和对照(control,CN)组,每组15只。利用3.0 T MRI获取增强T1WI图像,并测定图像CR、偏度(Skewness)和峰度(Kurtosis)。同时检测血清淀粉酶、脂肪酶及肌酐水平,进行组织学评分(histological score,HS),测定诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)表达。采用Spearman秩相关系数分析影像学参数与病理指标间的相关性,进一步使用多元回归分析构建AP损伤预测模型,通过受试者工作特征(receiver operating characteristic,ROC)曲线评价模型预测效能。结果AP组影像指标明显异常,CR和Skewness升高(P<0.001),Kurtosis降低(P<0.05),差异均有统计学意义;ET组三项影像指标均较AP组改善(P<0.05),差异具有统计学意义,并趋近CN组水平。相关性分析证明,CR与HS及iNOS阳性表达量呈显著中到高度正相关(ρ=0.64~0.85,P<0.001),Kurtosis与HS呈显著负相关(ρ=−0.84,P<0.001)。多元回归分析证明,CR为HS独立预测因子(β=6.69,P<0.05),而Kurtosis与HS呈显著负相关(β=−2.56,P<0.001),Skewness无独立预测价值(P>0.05)。以HS≥12作为重度AP的界值,CR+Kurtosis联合模型预测准确率达89.6%,曲线下面积(area under the curve,AUC)为0.95。结论CR、Skewness和Kurtosis能够从灌注状态与结构异质性两方面无创量化AP损伤。其中CR主要反映微循环灌注变化,Kurtosis与组织结构破坏程度相关性更强。多参数MRI能敏感检测大黄素减轻炎症、改善微循环的保护效应,为AP严重程度分级及治疗疗效动态评估提供可靠的无创影像学方法,具有潜在临床应用价值。

关键词： 教学应用   CAD工程制图   信息化教学   学生理解  

摘要： 引言,信息化技术在当前各个学科的教学中得到了广泛应用,就其在CAD工程制图教学中的应用来说,可以显著增强学生对课程知识的理解,减少其在学习中产生的疑问。本文以信息化教学形式的应用为主,分析其在CAD工程制图教学中的应用现状、作用与优势,探讨教学方法应用要点,致力于营造更加活跃的教学氛围,激发学生在课堂学习中的兴趣,为提高学生的学习水平提供理论与技术保障。

关键词： Content addressable memory (CAM)   High-speed search   Hybrid MLs   Local search   Pre-charge free CAM  

摘要： This high-speed, power-efficient content addressable memory (CAM) uses parallel lookups to match quickly without sacrificing power consumption. It introduces three key contributions: i. Pre-charge free operation, which improves search speed and reduces power requirements by eliminating node charging time, ii. A Hybrid Match Line (HML) structure that strategically balances power and delay, combining the high-speed attributes of NOR with the low-power attributes of NAND, and iii. Local searching technique ascertain further improvement in search time. Performance indicators improve greatly when these methods are seamlessly integrated. Utilizing 45 nm CMOS technology, the design supports diverse process voltages, temperatures, and frequencies for a 64x32 memory array. Monte Carlo simulations verify design stability. The proposed architecture outperforms the leading benchmark in speed and power-delay-product (PDP) by 54.6% and 76.02%, respectively. This novel design can do repeated data searches at frequencies up to 2 GHz after a single write operation, enabling quicker and more energy-efficient data processing that could revolutionize consumer electronics. This development could revolutionize consumer electronics by improving efficiency and speed in high-performance computing, mobile devices, and IoT applications.

摘要： Les caméras CZT offrent une meilleure détection des rayons γ, en particulier une résolution en énergie significativement améliorée qui pourrait être utile pour mieux prendre en compte la contribution du rayonnement diffusé. Ces nouvelles caméras bénéficient également de méthodes de reconstruction itératives avancées. Notamment l’utilisation de l’algorithme BSREM, qui contrôle le bruit au cours du processus. La qualité d’image et les performances de quantification ont été analysées pour deux corrections de diffusion et deux méthodes de régularisation (Median Root Prio et Relative Difference Prior).

关键词： 直肠癌   循环肿瘤细胞   立即早期反应3   免疫组化染色  

摘要： 目的分析直肠癌组织和术前循环肿瘤细胞(CTCs)中立即早期反应3(IER3)的表达情况,并研究其与患者临床病理特征的关联性。方法招募广西壮族自治区人民医院2017年1月至2019年1月收治的直肠癌患者42例,健康体检者42名。患者于术前1 d采集外周血5 m L(健康体检者于体检时采集),通过原位杂交技术检测术前CTCs水平及CTCs中IER3 mRNA的表达情况,并进行CTCs分型。采用实时荧光定量聚合酶链反应(qRT-PCR)检测直肠癌组织及癌旁组织中IER3 mRNA表达水平,采用免疫组化染色检测组织IER3蛋白表达情况。分析直肠癌组织IER3 mRNA表达水平与患者临床病理特征的关联性。分析直肠癌组织IER3的mRNA和蛋白表达与CTCs水平的相关性。分析CTCs水平以及IER3 mRNA阳性表达的CTCs水平与患者临床病理特征的关联性。随访截至2023年12月31日,分析直肠癌组织IER3 mRNA和蛋白表达水平与患者生存预后的关联性。结果直肠癌组织IER3 mRNA表达水平及IER3蛋白阳性表达率显著高于癌旁组织(P<0.05)。健康体检者中均未检测到CTCs。直肠癌患者术前CTCs检出率为92.86%(39/42),其中29例患者CTCs中存在IER3 mRNA表达,表达率为74.36%(29/39)。不同类型CTCs的IER3 mRNA表达情况无显著差异(P>0.05)。Spearman秩相关分析结果显示,直肠癌组织IER3 mRNA表达水平与总CTCs水平呈负相关(r_(s)=-0.317,P=0.041)。直肠癌组织IER3蛋白表达情况与总CTCs、混合型CTCs水平具有显著关联(P<0.05)。CTCs水平与患者临床病理特征无显著关联(P>0.05)。IER3 mRNA阳性表达的间质型CTCs水平与患者N分期、T分期、TNM分期有显著关联(P<0.05)。IER3 mRNA阳性表达的上皮型CTCs、混合型CTCs及总CTCs水平与患者临床病理特征均无显著关联(P>0.05)。直肠癌组织IER3蛋白及mRNA表达情况与患者生存预后无显著关联(P>0.05)。结论IER3在直肠癌组织中呈高表达,且与肿瘤侵袭转移相关病理特征及CTCs的数量、亚型存在关联性。