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关键词： CAD/CAM provisional materials   in vitro wear tests   wear parameters   surface topography   clinical performance  

摘要： In order to provide clinically significant evidence on the long-term functional performance of CAD/CAM provisional materials, especially 3D-printed and milled resins, accurate tribologically in vitro wear tests that integrate wear parameters and surface topography analysis are necessary. The goal of the study was to assess the wear resistance of several CAM-obtained dental crown materials and the relationship between wear and the manufacturing process, distinctive postprocessing, microhardness, microroughness, and surface topography. A standardized ball-on-flat tribological protocol was applied to (n = 70) CAD/CAM-fabricated PMMA specimens (four 3D-printed groups with distinct post-processing protocols (Optiprint) and three milled materials (TelioCAD, Shaded PMMA, Copra Temp Symphony)) to quantify wear parameters micro- and nanoroughness (Ra, Rz, Sa, Sy), and Vickers microhardness, followed by comprehensive statistical analysis (t-tests, Pearson correlations) to elucidate material- and process-dependent differences in wear behaviour. Nanoroughness was carried using atomic force microscopy evaluation. Wear testing showed that most materials, particularly the 3D-printed groups, developed limited wear, whereas the milled materials evolved toward groove-dominated wear topographies. Wear statistics showed that the printed resins consistently had an advantage, meaning that the degree and rate of wear are significantly influenced by the manufacturing process. Hardness has a central role in governing the wear performance of interim resin materials, while nanoroughness acts as a secondary factor. Optimised post-processing of printed materials, particularly a prolonged post-curing period, yields a beneficial combination of low wear and specific topography, thereby providing a significant clinical advantage.

关键词： Dental materials   Three-Dimensional printing   Ceramics   Biocompatibility   LC-MS/MS  

摘要： Objective This study aimed to compare surface properties, degree of conversion (DC), short-term eluate levels, and biocom-patibility between high-filler three-dimensional (3D) printed dental resins, low-filler 3D printed dental resins, and milled ceramic materials.
Materials and methods Two commercial high-filler 3D printed resins (containing zirconia and silica), one commercial low-filler 3D printed resin, one hybrid milled ceramic, and one zirconia milled ceramic were tested. The surface properties evalu-ated were degree of conversion (DC) (n = 10), contact angle and surface free energy (SFE) (n = 10), surface roughness using contact-type profiler (n = 10) and Atomic Force Microscopy (AFM, n = 1) and surface morphology using Scanning Electronic Microscopy (SEM, n = 1). Biocompatibility was assessed by measuring the viability (n = 10), proliferation (n = 3), and migra-tion (n = 6) of human gingival fibroblasts after exposure to material eluates. Eluates were analyzed subjectively using liquid chromatography-tandem mass spectrometry (n = 1). Data were analyzed statistically using one-way ANOVA with Tukey's HSD test (alpha = 0.05).
Results High-filler resins showed significantly higher DC than the low-filler resin (p < 0.05). Postcuring increased DC in the low-filler resin but not in high-filler resins. High-filler resins and the hybrid ceramic exhibited higher surface energy and lower contact angles than zirconia and the low-filler resin, while surface roughness was highest in the hybrid ceramic and lowest in the low-filler resin (p < 0.05). Eluates had no effect on viability or proliferation but significantly reduced fibroblast migration for the high-filler resins and hybrid ceramic (p < 0.05).
Conclusions High-filler 3D printed resins demonstrated higher DC and surface energy but released more residual monomers than the low-filler resin and ceramics. While eluates did not impair cell viability or proliferation, they reduced fibroblast migration,

关键词： resistance training   variable-cam   torque   moment arm   strength curves  

摘要： Resistance training machines are designed to provide either constant or variable resistance, with the latter intended to generate a machine resistive torque (MRT) that mirrors the natural fluctuations in human torque capability (HTC) across joint angles. Yet, achieving a precise match between MRT and HTC remains a persistent challenge. This study aimed to validate a novel variable-cam resistance system, the Variable Moment Arm Cam (R) (VMAC (R)), by examining torque output and muscle activation during leg extension across the full range of motion (100-0 degrees), using repeated testing and direct comparison with an isokinetic dynamometer. Twenty-two young men completed four randomized sessions, two on the variable-cam system and two on the dynamometer, each separated by 72-96 h. Torque and muscle activity were recorded during six isometric contractions at 100 degrees, 80 degrees, 60 degrees, 40 degrees, 20 degrees, and 0 degrees. The variable-cam system produced torque and activation patterns broadly comparable to the dynamometer, with acceptable agreement across angles. Validity was highest at 60 degrees, aligning with the region of peak torque, whereas greater variability emerged at the extremes of flexion and extension. Muscle activation profiles were similar between devices, though more variable than torque, underscoring the inherent complexity of neuromuscular assessment.

关键词： Orthodontic retainers   Lingual retention   Computer-aided design   Transfer accuracy   Nickel-titanium   Cobalt-chromium  

摘要： Objectives This study aimed to evaluate the immediate three-dimensional (3D) transfer accuracy of three virtually designed CAD/CAM lingual retainers fabricated from nickel-titanium (NiTi), titanium grade 5 (Ti5), and cobalt-chromium (CoCr). The investigation represents the baseline (T = 0) phase of a registered randomized clinical trial (DRKS00028974). Materials and methods Sixty patients (32 females, 28 males;mean age 19.2 +/- 6.9 years) were randomly allocated to receive one of the three CAD/CAM retainers. Immediately after bonding (T0-T1), intraoral scans were superimposed with the digital design to determine deviations at predefined interproximal contact points. Non-parametric Kruskal-Wallis tests with Dunn's post-hoc comparisons were applied (p <= 0.05). Results All 60 patients completed the baseline assessment. Transfer deviations were lowest in the NiTi group (0.17 mm, IQR 0.16-0.21), followed by Ti5 (0.37 mm, IQR 0.32-0.41) and CoCr (0.35 mm, IQR 0.30-0.40). NiTi showed significantly higher transfer accuracy compared with Ti5 (p < 0.001) and CoCr (p < 0.001). No significant difference was observed between Ti5 and CoCr (p > 0.999). No adverse events occurred. Conclusions Laser-cut NiTi CAD/CAM retainers demonstrated significantly higher immediate transfer precision than milled Ti5 and CoCr retainers. These findings represent the baseline phase of the ongoing randomized clinical trial;subsequent analyses will determine whether such accuracy differences translate into clinically relevant stability outcomes. Clinical relevance Accurate passive fit of CAD/CAM retainers is essential to prevent unwanted forces on teeth. Understanding material-dependent transfer deviations may improve digital bonding workflows and guide material selection in clinical orthodontics.

关键词： air permeability   woven fabric   filament assembly model   CAD   CFD   textile simulation  

摘要： This study presents the development of a three-dimensional (3D) filament assembly model for predicting the air permeability of woven fabrics composed of spun yarns. To address the limitations of conventional single-line yarn models, the proposed framework incorporates fiber-level geometric representations using non-uniform rational B-splines (NURBS) and simulates multiple weave patterns-including plain, basket, twill, and rib-under various set density configurations. Each yarn was modeled with accurate filament distribution and cross-sectional layering, enabling the construction of realistic unit-cell-based CAD geometries. Computational fluid dynamics (CFD) simulations were performed using the k-epsilon turbulence model in SolidWorks Flow Simulation and validated against experimental measurements conducted under ISO 9237:1995 conditions. The filament assembly model achieved high predictive accuracy, exhibiting a lower of percentage prediction errors than the single-line yarn path model, thereby more effectively capturing airflow behavior through inter-yarn and intra-yarn pores. These findings highlight the capability of integrated CAD/CFD methodologies for virtual prototyping of breathable textiles and provide a robust foundation for high-precision performance prediction in functional and technical fabric design.

关键词： breast neoplasms   computer-assisted   mammography   mass screening   reproducibility of results  

摘要： Background Full-field digital mammography (FFDM) is the standard for breast cancer screening. Digital breast tomosynthesis (DBT), compared to FFDM, enhances cancer detection and reduces unnecessary biopsies. Despite DBT's adoption, critical questions remain-higher radiation, time, cost, and clinical benefits, particularly for systematic breast screening. In the era of AI computer-aided detection/diagnosis (CAD) for breast screening, one unresolved question is the role of bimodal algorithms in predicting cancer and offering guidance when opinions differ, and we aim to understand *** We retrospectively assembled an enriched screening cohort of 1,816 women who underwent both FFDM and DBT at two Hologic sites. Analyses requiring paired CAD scores were performed on a lesion-level subset for which both FFDM and DBT CAD scores were available (low suspicion = 1;high suspicion = 10) and reference standard outcomes were known, comprising 1,071 lesions from 657 examinations. From the joint distribution, we defined areas of "perpendicular scoring" (PS) as the areas of highly discordant scoring. We estimated the inter-modality agreement using the three classes (low, indeterminate, and high suspicious) with Cohen's kappa index. We evaluated the potential of systematic, lossless, and AI-powered reclassifications of PS both for tumoral masses and calcifications and in considering breast density as a risk factor for *** We observed a moderate inter-modality agreement, indicated by a kappa of 0.49 (95% CI: 0.46-0.52). PS scoring was present in 32.7% (95% CI: 29.7-35.8) of tumoral masses (soft tissue lesion) cases and 38.6% (95% CI: 30.1-47.6) of calcification cases. Breast density was a risk factor of PS for masses (odd, 0.66 [95% CI: 0.48-0.91]). AI-powered and lossless models were found effective for reclassifying 82.2% and 67.3% of PS of masses and calcification, *** When processed by CAD, FFDM and DBT provided complementary information at the

关键词： adhesion-clutch   cell motility   glioblastoma   haptotaxis   L1CAM  

摘要： L1CAM is a member of the immunoglobulin superfamily involved in cell adhesion, migration, and neural development. While several studies have shown an association between L1CAM and glioblastoma (GBM) cell motility, its mechanobiological function in patient-derived primary cultured GBM cells remains insufficiently understood. This study focuses on L1CAM-dependent motility mechanisms in patient-derived GBM cells at the single-cell level. Patient-derived GBM cells were established from GBM tissues using the neurosphere method. L1CAM expression was evaluated by qPCR, western blotting, flow cytometry, and immunocytochemistry. Cell motility was assessed by single-cell tracking. Functional assays included forced expression and antibody-mediated inhibition of L1CAM. Adhesion-clutch behavior and retrograde F-actin flow were analyzed. For in vivo assessment, doxycycline-inducible L1CAM-overexpressing GBM cells were transplanted into mouse brains. L1CAM-high GBM cells showed increased motility on laminin compared to L1CAM-low cells. Anti-L1CAM antibody suppressed migration of L1CAM-high GBM cells, whereas ectopic expression enhanced migration in L1CAM-low GBM cells. L1CAM-positive GBM cells preferentially migrated on laminin rather than fibronectin, while L1CAM-low cells showed no such difference, indicating L1CAM-dependent haptotaxis. Forced L1CAM expression reduced retrograde actin flow velocity and promoted adhesion-clutch formation. In vivo, GBM cells with L1CAM overexpression displayed greater infiltrative capacity 12 weeks posttransplantation. L1CAM expression on GBM cells' surface regulates cell motility through adhesion-clutch mechanisms and substrate sensing. These mechanobiological features suggest that targeting L1CAM may serve as a promising strategy to suppress GBM cells infiltration and improve GBM treatment outcomes.

关键词： Sarcoma   Chick embryo chorioallantoic membrane (CAM) model   Tumor cell-conditioned medium (TCM)   Bio-imaging   Angiogenesis   VEGFA  

摘要： We developed a sensitive bioimaging system for sarcoma by creating a cell line that stably expresses both Katushka2S fluorophore and NanoLuc luciferase, enabling robust dual tracking of tumor growth and metastasis in the chick chorioallantoic membrane (CAM) model. NanoLuc luciferase was notably more effective than Katushka2S for identifying tumor cell metastases in embryo tissues. Pretreating CAM with tumor cell-conditioned medium (TCM) significantly increased neovascularization, Ki67 expression, tumor volumes, and metastasis of the most difficult-to-establish low-tumorigenic and low-metastatic U2OS cells, indicating that tumor cell secretome actively alter the CAM vascular environment to aid tumor progression. The bead-based multiplex profiling of the TCM demonstrated a notable increase in pro-angiogenic factors. Neutralizing VEGFA, the most abundant factor in the TCM, effectively counteracted vascular and pro-metastatic effects of TCM. In contrast, elevating VEGFA levels brought back the pro-tumorigenic effects of TCM. This study reveals the importance of tumor cell secretomes in creating the vascular niche in CAM and points to VEGFA as a target to prevent secretome-induced angiogenesis and sarcoma development. Furthermore, our optimized CAM model permits continuous tumor growth and metastasis monitoring in embryonic development, providing a reliable platform for prognostic studies of sarcoma treatments in ongoing anti-angiogenic and multikinase inhibitors trials.

关键词： 3DGS   novel view synthesis   scene reconstruction   dash cam video  

摘要： Recent advancements in 3D Gaussian Splatting (3DGS) have made significant improvements in real-time novel view synthesis and 3D reconstruction. 3DGS has seen significant development in driving scenarios, but existing methods are mainly designed for videos captured by autonomous vehicles. It is not suitable for the complexity and dynamic lighting challenges present in dash cam videos. Despite the progress made by previous work in dealing with reflections and occlusions, the distribution of 3D Gaussian points remains inaccurate due to the inherent complexity of dash cam scenes, causing geometric distortions in the rendered output. Additionally, uncontrolled dynamic illumination exacerbates Gaussian point density anomalies and local geometric distortions. These challenges significantly hinder the development of scene reconstruction techniques based on dash cam videos. To address these challenges, we present RDC-GS, an innovative method featuring a point correction mechanism to eliminate distribution errors of Gaussian points during training, and a brightness-aware illumination technique to enhance detailed representation under dynamic lighting conditions. This approach yields more robust scene reconstruction. Experiments conducted on real dash cam videos demonstrate that our method achieves a 1.5-dB PSNR improvement over current state-of-the-art techniques. Comprehensive experiments validate the efficacy of our approach across challenging scenarios.