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关键词： Flexural properties   Surface hardness   Milled CAD/CAM   Denture base resin  

摘要： Objective The objective of this study is to evaluate the flexural strength and surface hardness of denture base resins that have been milled using computer-aided design and computer-aided manufacturing milling (CAD/CAM) and conventional heat-polymerized denture base resins (HP). Methods Eighty samples were made using CAD/CAM resin material (Polident CAD/CAM and Interdent CC discs) and conventional heat-polymerised acrylic resin (HP) (IvoBase CAD and PMMA). Based on the denture base material, the samples were categorised into eight groups: each group (n = 10), flexural strength (n = 40), surface hardness (n = 40). Both the surface hardness and flexural strength were evaluated using the Vickers hardness test and the three-point flexure test, respectively. A statistical analysis with a significance level of alpha = 0.05 was used to analyze the data. Results Compared with HP resins, milled CAD/CAM resins demonstrated significantly higher flexural strength and surface hardness (p < 0.001). The flexural strength of MHC 72.72 +/- 5.95 is significantly lower than that of IHC 78.96 +/- 3.36, PCC 108.59 +/- 6.51, and VCC 99.88 +/- 6.05 MPa. Surface hardness is significantly lower in MHC (18.40 +/- 2.28 VHN) than in the other groups: IHC (21.30 +/- 2.40 VHN), PCC (31.07 +/- 2.07 VHN), and VCC (27.09 +/- 1.55 VHN). Conclusion Compared with heat-polymerized acrylic resin, milled CAD/CAM resins performed exceptionally well in terms of flexural and surface mechanical properties.

关键词： color stability   surface roughness   CAD/CAM restorative materials   resin nanoceramic   hybrid ceramic   coffee staining  

摘要： The long-term esthetic performance of indirect restorations is closely related to the color stability and surface integrity of the restorative materials used. With the increasing use of CAD/CAM technologies, a wide range of ceramic- and resin-based materials have been developed for indirect restorative applications. These include feldspathic ceramics (VITA Mark II, VITA Zahnfabrik), hybrid ceramics (VITA Enamic, VITA Zahnfabrik), resin nanoceramic CAD/CAM blocks (Lava Ultimate, 3M), and indirect microhybrid resin composites (GC Posterior, GC Corporation). However, these materials are continuously exposed to chemical and mechanical challenges in the oral environment, such as staining from beverages and daily toothbrushing, which may compromise their optical and surface properties over time. The purpose of this in vitro study was to evaluate and compare the color change (Delta E) and surface roughness (Ra) of these materials after repeated coffee immersion and simulated toothbrushing. A total of 240 disk-shaped specimens were fabricated and subjected to three aging cycles consisting of storage in coffee or distilled water, followed by simulated toothbrushing with or without toothpaste. The color parameters were measured using a spectrophotometer according to the CIE Lab* system, surface roughness was assessed using a contact profilometer, and surface topography was qualitatively analyzed by atomic force microscopy. The results demonstrated that coffee immersion significantly increased both color change and surface roughness for all tested materials, with more pronounced effects observed in resin-based materials. Ceramic-based CAD/CAM materials (VITA Mark II and VITA Enamic) showed greater resistance to discoloration and surface degradation, whereas the resin nanoceramic material (Lava Ultimate) and the microhybrid resin composite (GC Posterior) exhibited clinically perceptible color changes and higher roughness values, particularly after toothbrushing with toothpaste.

关键词： Scapula free flap   CAD/CAM   Mandibular reconstruction   Patient-specific implant   Free flaps   Accuracy   Microvascular transplant   Free bone transplant  

摘要： Purpose For the first time, this study explores the transfer precision of computer aided design and computer aided manufacturing (CAD/CAM) in mandibular reconstruction with scapula free flaps (SFF). Methods Patients undergoing mandibular reconstruction with SFF and patient-specific 3D-printed titanium plates were retrospectively analyzed. To assess planning accuracy, pre-and postoperative datasets were overlaid using 3D Slicer software. Specific measurements included the fit at the mandibular resection site, intersegmental gap width between scapula and mandible, scapular segment positioning, and condylar alignment. Osseous union was evaluated via postoperative computed tomography (CT) or cone beam CT, and plate-related complications were recorded clinically. Results In total 15 patients (mean age 65.7 +/- 10.0 years) were included. Postoperative scapular segment positioning showed deviations in the posterior region (basal: 6.78 +/- 3.34 mm;crestal: 7.61 +/- 3.40 mm) and anterior region (basal: 3.54 +/- 1.52 mm;crestal: 4.49 +/- 2.51 mm). Mean deviation in segmental gap width at the anterior and posterior sites ranged from 0.55 to 1.72 mm and was statistically significant at all four measurements. Mean contralateral condyle position differed significantly from the initial position (8.56 +/- 4.31 mm). Intraoral plate exposure occurred in three patients without adjuvant radiotherapy;no extraoral exposure, fractures, or loosening were observed. Non-union between the mandible and SFF was found in three patients. Conclusion As with other CAD/CAM-assisted mandibular reconstructions, SFF exhibit discrepancies between virtual planning and the postoperative outcome. The surrounding soft tissue bulk of the scapula can hinder the precise fit of cutting guides, potentially compromising reconstruction accuracy and contributing to increased deviations. Despite these challenges, CAD/CAM-assisted SFF demonstrates acceptable surgical predictability.

关键词： Radiomics   Pericoronary adipose tissue   CT-FFR   T2DM with CAD   Machine learning   SHAP  

摘要： This study aims to integrate lesion-specific pericoronary adipose tissue (PCAT) radiomics analysis with existing clinical and imaging methods under the guidance of CT-derived fractional flow reserve (CT-FFR), to develop and validate an interpretable machine learning (ML) prediction model for patients with type 2 diabetes complicated by coronary artery disease (CAD). The performance of ML algorithms across different predictive models was compared using the area under the receiver operating characteristic curve (AUC). In the validation cohort, the XGBoost algorithm within the combined model achieved an AUC value of 0.908, outperforming the best algorithm in the traditional model (AUC = 0.834) and radiomics model (AUC = 0.840). Meanwhile, the Shapley algorithm highlights the additional incremental value of radiomic features. Our model enhances the predictive ability and provides clinicians with a comprehensive tool, facilitating early intervention for high-risk individuals and proactive secondary prevention strategies, which may potentially improve clinical outcomes.

关键词： Alternative medicine   CAM   Debunking intervention   Health misinformation   Empathetic-refutational interview  

摘要： Debunking interventions to tackle misconceptions related to scientific issues have gained momentum, especially in the context of health care. In this randomized controlled experiment, we assessed the effectiveness of tailored (i.e., contrarian information addressing participants' specific motives with an affirmation of their psychological profile) and non-tailored (i.e., general contrarian information regardless of participants' psychological profile) debunking interventions in a sample of 167 Peruvian participants with positive attitudes toward egg cleanse, a popular local alternative medicine treatment. Our debunking interventions did not significantly correct attitudinal variables related to egg cleanse, such as belief in effectiveness, future use, and preference over conventional medicine. However, exploratory analyses showed significant reductions in endorsement of usage reasons within both the tailored debunk (d = 0.50) and non-tailored debunk (d = 0.62) groups. Moreover, a comparison between the two debunking groups indicated that participants who received a tailored debunk were more satisfied with the interaction with the physician than those who received a non-tailored debunk (d = 0.73). These results suggest that debunking interventions on misinformed health beliefs could have an impact also in the Peruvian cultural context and for alternative medicine, even though more direct attitudinal variables are particularly resistant to change. Strengths and weaknesses of tailored and non-tailored approaches to health misinformation, as well as future research pathways to shed light on the impact and pitfalls of debunking interventions, are discussed.

关键词： Herbal medicine   peptic ulcer   Complementary medicine   Probiotics   Liquorice   Pharmacognosy  

摘要： Peptic ulcer disease (PUD) is still a global health problem, and Helicobacter pylori infection is identified as the principal causative factor. While these are effective, the conventional pharmacological treatments are usually accompanied by side effects, the development of antibiotic resistance, and limited access in some cases. As a result, Complementary and Alternative Medicine (CAM) has become a promising complementary or alternative intervention for PUD. The objective of this systematic review was to assess the therapeutic value, safety, and constraints of CAM interventions for peptic ulcer disease. An extensive systematic review was performed using the PICO format and reported following guidelines, including Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Literature searches were conducted in multiple databases, including the Cochrane Library, Embase, MEDLINE, and the Complementary Medicine Database and included papers from 2000 to 2024. Herbal treatment, complementary medicine, and alternative medicine were the search terms. Available full-text studies had a focus primarily on CAM interventions for PUD. Data were tabulated and synthesized to summarize therapeutic mechanisms, safety profiles, and limitations of the studies. A total of 134 studies met the inclusion criteria, including randomized controlled trials (n approximate to 45), observational studies (n approximate to 30), systematic reviews and meta-analyses (n approximate to 20), and preclinical experimental studies (n approximate to 39). Herbal medicine was studied the most in CAM. There were agents such as Nigella sativa, licorice, turmeric, Aloe vera, and ginger, with gastroprotective, Antioxidant, and anti-H. Pylori effects. Probiotics and acupuncture were supportive, too. Compared to conventional therapies, CAM therapy caused fewer adverse effects. Some drawbacks included heterogeneity in herbal preparations, no standardized dosing, small patient populations, and limit

关键词： B-spline hyperpatch   human knee joint   heterogeneous material modelling   isotropic mesh modelling   reverse engineering  

摘要： Current knee joint reconstruction and visualization are done with the help of CAD modelling software. In this present article, the hyperpatch-based heterogeneous CAD modelling approach has been used to study the knee joint. The peculiarity of this proposed approach is that while constructing the unevaluated model, the B-spline tensor product-based methodology within the control-point-based framework is employed for the heterogeneous CAD model creation. The modelling methodology utilizes the coding and data-extraction tools for reverse engineering and obtaining the necessary data set for reconstructing the heterogeneous material model. Along with the heterogeneous hyperpatch CAD model of the knee joint, the mesh models are generated by utilizing the curves forming the hyperpatch. The obtained mesh models can be used for finite element analysis purposes. The relationship between the number of nodes and material properties was also investigated.

关键词： Drive mechanism   Pressure plate   Flat die-cutting press   Deformation   Hardness   Cam   Law of periodic motion  

摘要： A diagram is proposed, and the principle of operation of the drive mechanism of the pressure plate of a flat die-cutting press is described. The deformations and the required hardness of the working contact surfaces of the executive elements (cams and rollers) of the structure are analytically investigated. The coefficients, which relate the required hardness of the working contact surfaces of parts and material strength, are calculated. Six laws of periodic motion of the corresponding executive link are used in the research, in particular, the smallest values of deformations (triangle = 6.13x10-6 m) and hardness (HB = 1582.1 MPa) of the cams and rollers are established according to the law of periodic motion "Sinusoidal acceleration (symmetrical tachogram)".

关键词： CAD/CAM   fracture resistance   hybrid resin composites   luting   occlusal overlays  

摘要： Objective To assess the influence of various bonding protocols on the fracture resistance and failure mode of CAD/CAM-milled hybrid resin composite occlusal *** and Methods Fifty sound human premolars (n = 50) were sectioned to expose superficial dentin surrounded by enamel. Each specimen was digitally scanned and restored with a CAD/CAM-milled hybrid resin composite overlay designed in Exocad DentalCAD. The restorations were assigned to five groups (n = 10) based on the luting protocol: Group I, Calibra Ceram;Group II, SDR Flow;Group III, heated Grandio;Group IV, Panavia F2 (self-etch), and Group V, Calibra Universal (self-adhesive). All specimens underwent thermomechanical aging simulating 1 year of clinical service, followed by compressive load testing at 1 mm/min until fracture. Failure modes were examined under magnification. Statistical significance was set at p < *** Group III (heated Grandio) exhibited the highest mean fracture load (1728.28 +/- 156.64 N), whereas Group II (SDR Flow) showed the lowest (835.49 +/- 151.69 N). Groups I, IV, and V demonstrated intermediate, statistically comparable values (p > 0.05). Tukey's HSD confirmed significant differences between Groups II and all others (p < 0.001) and between Group III and Groups IV-V (p < 0.001).Conclusions Bonding strategy significantly affects the mechanical performance of hybrid resin composite overlays. All tested protocols achieved clinically acceptable strength based on ISO DIS 6872, confirming milled hybrid resin overlays as a conservative and durable restorative *** Significance Selecting an optimal bonding strategy, particularly using heated resin composites, can enhance the durability and fracture resistance of conservative CAD/CAM hybrid resin overlays, offering a viable minimally invasive alternative to full-coverage crowns.

摘要： The Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) is a deep wide-field multiband imaging survey consisting of three layers (Wide, Deep, and UltraDeep), with the Wide layer covering similar to 1470 deg2 to a depth of i similar to 26 mag. We present the QHSC catalog, a machine learning-selected sample of quasar candidates with photometric redshifts in the Wide layer of the HSC-SSP survey (Public Data Release 3). The full QHSC catalog contains four distinct samples: a Master Sample with HSC-only photometry, an HSC+WISE sample, and two samples including near-infrared data from UKIDSS and VISTA surveys, denoted as GoldenU and GoldenV. For each sample, an XGBoost classifier is trained and evaluated using independent spectroscopic test sets from HETDEX, VVDS, and zCOSMOS-bright. The numbers of quasar candidates in the QHSC catalog are 1,184,574 (Master), 371,777 (HSC+WISE), 87,460 (GoldenU), and 120,572 (GoldenV), with respective completeness values of 85.3%, 92.7%, 89.8%, and 91.3%. We develop ensemble photometric redshift estimators based on bootstrap aggregating (bagging) of multiple XGBoost regressors, achieving outlier fractions of 21.7%, 13.1%, 9.5%, and 10.7% for these samples. The catalog provides quasar classification probabilities (pQSO), enabling construction of purer subsamples via thresholding. This work offers a valuable resource for studies of quasars and cosmology, and highlights the effectiveness of machine learning for quasar selection in future wide and deep imaging surveys. The catalog is publicly available at doi:10.5281/zenodo.17515028.