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关键词： automated integration framework   CAD-CAE integration   feature recognition   small language model   prompt engineering  

摘要： Automated CAD-CAE integration, which links computer-aided design (CAD) and computer-aided engineering (CAE), is one of the key strategies for reducing repetitive tasks in the design process. However, setting analysis parameters and assigning boundary conditions for variously designed shapes require expert knowledge and precise recognition of topological elements, remaining a major challenge to full automation. To address these issues, this study proposes an automated integration framework. The framework utilizes a small language model (SLM) and prompt engineering to extract analysis and validation parameters from unstructured documents. Additionally, boundary faces are selected through design feature recognition. The parameter extraction performance was evaluated using four language models developed by different providers and trained at different scales. The evaluation showed consistent extraction accuracy across all models. Boundary condition assignment was verified using CAD models including cup-anemometer and snap-fit hook features, achieving 100% accuracy in all experiments. The effectiveness of automation was assessed by comparing the number of manual inputs and the total analysis time. The experimental results showed reductions of 97.06% in manual inputs and 63.92% in analysis time per CAD model. These experimental results demonstrate the effectiveness of a framework that enables the entire analysis process to be executed without human intervention. The study provides a practical solution to the challenges of parameter setting and boundary condition assignment. Furthermore, the proposed method presents an innovative approach that can be generally applied to performance analysis of complex and diverse CAD models and experimentally verifies the benefits achievable through full automation.

关键词： 3D printing   CBCT   CAD   Alveolar bone regeneration   Patient-specific scaffolds   Biodegradable materials   Bone tissue engineering  

摘要： Background:Alveolar bone loss following trauma, periodontal disease, congenital anomalies, or tooth extraction poses a major challenge for oral rehabilitation, especially in implant dentistry. Traditional grafting techniques using autografts, allografts, or xenografts provide limited predictability due to issues of resorption, donor morbidity, and immune incompatibility. Advances in three-dimensional (3D) printing now enable preparation of patient-specific biodegradable scaffolds designed using 3D imaging, like cone beam computed tomography (CBCT) and computer-aided design (CAD), allowing precise replication of defect geometry and tailored biological ***:This review article summarizes the most recent preclinical and clinical studies investigating biodegradable 3D printed scaffolds for alveolar bone regeneration. Studies were searched in the PubMed database, Scopus, and Google Scholar with the most relevant keywords related to 3D printed scaffolds focusing on alveolar bone ***:Polymers such as PLA, PCL, and PLGA offer mechanical stability and printability but require bioactive modification. Ceramics, including hydroxyapatite and tricalcium phosphate, provide osteoconductivity yet are brittle. Hydrogels such as gelatin and alginate support cellular viability but lack structural strength. Composite scaffolds integrating polymers with ceramics or bioactive agents demonstrated superior osteogenic potential. Clinical applications included alveolar ridge preservation, guided bone regeneration, cleft repair, and implant site reconstruction. Emerging strategies utilizing bioinks with stem cells and growth factors further enhanced the biological properties of patient-specific 3D printed scaffolds for clinical ***:3D printed patient-specific biodegradable scaffolds represent a promising alternative to conventional grafting, offering precise defect reconstruction, improved biological integration, and translational potential in ma

关键词： CAD models   mesh generation   self-intersection   watertightness  

摘要： The tessellation of Computer-Aided Design (CAD) models into high-quality triangular meshes is a fundamental preprocessing step for downstream applications in visualization, numerical simulation, and digital manufacturing. While modern boundary representation models are typically geometrically valid and free of self-intersections, their tessellation frequently introduces artificial geometric artifacts-including self-intersections and gaps-particularly in regions containing narrow features or high-curvature surfaces. This paper presents a robust, general framework for watertight B-rep tessellation with three key contributions. First, we introduce mathematically rigorous definitions of critical points and critical regions that characterize local geometric behavior;our analysis proves that sampling constrained to these regions guarantees intersection-free refinement under arbitrary resolution. Second, we develop an accelerated spatial indexing structure using a novel parallel hexahedron bounding volume hierarchy, which dynamically adapts to geometric complexity while minimizing the number of required critical regions. Third, we propose an improved constrained Delaunay triangulation algorithm that, when guided by critical regions, simultaneously enforces watertightness and optimal element quality across surface patch boundaries. Comprehensive experimental evaluations against state-of-the-art geometric kernels (NetGen, Gmsh, and Open CASCADE) demonstrate our method's superior performance in generating intersection-free meshes with enhanced geometric fidelity and computational efficiency.

关键词： abrasion   CAD-CAM ceramic   color stability   erosion   glaze firing  

摘要： Purpose: To evaluate the effect of erosive-abrasive challenge on the optical properties, microhardness, and surface morphology of CAD-CAM ceramics with different surface finishing protocols. Methods: CAD- CAM ceramics used were: IPS *** CAD (DIS), IPS Empress CAD (LEU), Cerec Blocs (FEL), and Celtra Duo (CEL). Specimens were divided into five groups (n = 10): Polishing (P), Conventional Glaze (CG-control), Conventional Glaze with 2 firings (CG(2)), Extended Glaze firing (EG), and Extended Glaze with 2 firings (EG(2)). An erosive-abrasive challenge was performed with citric acid and simulated toothbrushing. Color change (Delta E-00), translucency, contrast ratio, gloss, Vickers microhardness, and surface morphology were evaluated. The evaluations were performed before and after the erosive-abrasive challenge. Delta E-00 was analyzed with one-way ANOVA with Welch correction and Games-Howell, while the other data were evaluated with two-way repeated measures ANOVA and Bonferroni post-test (alpha = 0.05%). Results: After the challenge, CG groups showed clinically unacceptable color changes. Translucency decreased in LEU-P, FEL-P, FEL-EG, and CEL-EG groups, but increased in DIS-CG(2), DIS-EG(2), and CEL-EG groups. The contrast ratio was close to 1. No gloss reduction was observed in CG groups. Microhardness decreased in DIS-EG, DIS-EG(2), LEU, FEL, and CEL groups, but remained unchanged in LEU- CG, FEL-CG(2), and CEL-EG(2) groups. Conclusion: Erosive-abrasive challenge affected the properties of CAD-CAM ceramics with different behaviors depending on the surface finishing protocol used. Clinical Significance: The optical properties and microhardness of CAD-CAM ceramics are negatively affected by erosive-abrasive conditions. Manual polishing showed similar performance in maintaining these properties and may represent a viable and effective alternative to glaze application.

关键词： Additive manufacturing   Pediatric partial denture   Subtractive manufacturing   CAD-CAM  

摘要： Background: The complete digitalization of pediatric partial denture (PPD) is progressing rapidly and holds promise for pediatric dentistry. However, the machining accuracy of subtractive manufacturing (SM) and additive manufacturing (AM) produced by computer-aided design-computer aided manufacturing (CAD-CAM) systems has not been clarified. Therefore, we aimed to evaluate the machining accuracy of PPD manufactured by SM and AM. Methods: The machining accuracy was evaluated based on the accuracy of mucosal surface fitting of the three types of PPDs (control-PPD, SM-PPD, and AM-PPD) and the accuracy of the design data for SM-PPD (n = 6) and AM-PPD (n = 6). Standard Tessellation Language (STL) data of the digital design, the mucosa surface of the jaw model, and the polished surface of each PPD (control, SM, AM), as well as the scanned STL data of each PPD produced by CAD-CAM were superimposed using Artec Studio 12 Professional software (Luxembourg). The data were superimposed and displayed in a color map. The mean root mean square (RMS) values standard deviation (SD) (mm) of the fit between the mucosal surface fitting of the control-PPD and the PPD fabricated using the CAD-CAM system and the jaw model were statistically compared using the Kruskal-Wallis test (alpha = 0.05). The average RMS values of the two design data accuracies were statistically compared using the Mann-Whitney U test (alpha = 0.01). Results: No significant difference was observed in the accuracy of mucosal surface fitting in the control-PPD, AM-PPD and SM-PPD. The mean RMS values (SD) (mm), which indicate the precision of design data, were 0.09840 (0.00315) and 0.06389 (0.00371) for the AM-PPDs and SM-PPDs, respectively. SM-PPDs showed significantly higher accuracy than the AM-PPDs (p = 0.002). Conclusions: Both methods achieved acceptable mucosal surface fitting;however, SM-PPDs showed higher machining accuracy than AM-PPDs. These findings support the integration of SM-based CAD-CAM systems in ped

关键词： Early delirium   acute ischemic stroke   screening tools   sensitivity   specificity  

摘要： Background and Objectives:Early post-stroke delirium (PSD) is difficult to diagnose and complicates recovery. We aimed to evaluate two validated delirium screening tools, focusing on patients with stroke-related higher-order cognitive deficits (HOCDs).Methods:We prospectively analyzed the delirium features and compared the diagnostic accuracy of the Confusion Assessment Method for ICU (CAM-ICU) and the Intensive Care Delirium Screening Checklist (ICDSC) with Diagnostic and Statistical Manual -5 (DSM-5) criteria in 164 patients with acute ischemic stroke. Early PSD was defined as delirium occurring within 72 h of ***:Early PSD occurred in 32.3% patients, two-thirds of whom had HOCDs such as aphasia or neglect. Individual delirium features were frequent in nondelirious patients with HOCDs, inattention (Area under curve [AUC] .98, odds ratio [OR] 28.88), psychomotor changes (AUC.95, OR 10.60), and impaired arousal (AUC.95, OR 8.57) had maximum discriminating value on logistic regression analysis. When compared with DSM-5, CAM-ICU (sensitivity 81%, specificity 84%, AUC.97) had better accuracy than ICDSC (sensitivity 70%, specificity 86%, AUC.96);however, both were noninferior. In patients with HOCDs, both had markedly reduced specificities. Adding psychomotor changes to patients who were CAM-ICU positive (CAM-ICU Plus) improved its specificity. CAM-ICU Plus (sensitivity 79%, specificity 92%, AUC.98) had the best accuracy among all the ***:Early PSD is common after ischemic stroke. Available screening tools have lower specificity in patients with post-stroke cognitive deficits. CAM-ICU performed better than ICDSC. CAM ICU Plus improves the specificity of CAM ICU, which needs to be confirmed by further multicenter studies. Stroke-specific delirium screening tools are required for improving outcomes.

关键词： Carnivorous plants   crassulacean acid metabolism   facultative CAM   heterophylly   Pinguicula   titratable acidity  

摘要： Crassulacean acid metabolism (CAM) is a photosynthetic adaptation enabling higher CO2 concentration close to Rubisco and increased water use efficiency. It evolved in at least 38 plant families, none reported to be carnivorous. Here, we investigate CAM activity in the carnivorous genus Pinguicula, so far reported as C3, with succulent leaves and distributed mainly in Central America. Eight species of Pinguicula, most with seasonal heterophylly, were cultivated under controlled conditions and monitored for changes in diel acidification (Delta H+) when grown with abundant or limited water availability. Additionally, leaf anatomy and gas exchange were studied in representative species. In the winter trial, five species had positive and significant Delta H+ 1 week after withholding water (P. agnata, P. esseriana, P. gigantea, P. laxifolia and P. moranensis). Delta H+ levels were in the range previously reported in weak, facultative CAM plants (15-30 mu mol H+ g-1 FW). The summer trial revealed positive Delta H+ for most species tested, regardless of water availability. Three of the homophyllous species had an unclear pattern of CAM induction (P. emarginata, P. martinezii) or no CAM induction (P. grandiflora). Gas exchange in P. agnata found no dark CO2 assimilation, suggesting CAM cycling. We present the first report of CAM in a carnivorous plant, reinforcing the need to search for CAM in other families. Future work should assess reversibility of the C3-CAM transition, explore the interplay between nutrient and carbon balance, and the contribution of weak CAM to plant fitness.

关键词： CAM   COVID-19   mucormycosis   stroke  

摘要： Background:Stroke is a very rare complication of rhino-orbital mucormycosis. Here we report a series of 24 patients with stroke due to mucormycosis, of whom 20 had recent or concurrent ***:This was a prospective observational study done in a tertiary care center in southern India conducted during August-October ***:This study included 24 patients (recent COVID-19 infection in 10, concurrent COVID-19 in 10, and COVID-19-negative in 4). Poorly controlled diabetes was present in 22 patients. Altered sensorium was the most common presentation. Anterior circulation was involved in all patients, and watershed infarction was the most common pattern. Despite aggressive management, 22 patients ***:Stroke due to mucormycosis has a very poor prognosis, especially with concurrent or recent COVID-19 infection.