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摘要： BackgroundThe passive fit of 3-unit implant supported prefabricated metal screw-retained prosthesis before implant placement might be difficult. Hence, we aim to evaluate the passive fit and time efficiency of CAD/CAM 3-unit implant supported fixed prostheses that were constructed based on virtual versus those based on actual implant positions in Kennedy Class I *** sample of 5 Kennedy class I models with thin wiry ridges were restored by 20 frameworks bilaterally, 10 based on actual (group A) and 10 based on virtual (group V) implant positions. The models were imaged using cone beam computed tomography and scanned using an intraoral scanner. The STL (Standard Tessellation Language files) and the DICOM (Digital Imaging and Communications in Medicine) files were registered on a 3D planning software. A CAD/CAM surgical guide was planned, resin printed and used for installing 6 implants bilaterally. In group V, the framework was designed based on the virtual scan bodies and virtual multi-unit abutments, while in group A intra-oral scanning of the model after attaching the scan bodies was necessary. Frameworks of both groups were milled and tested for passive fit using 8 clinical tests. McNemar and Wilcoxon signed rank tests were used to study the effect of the group on passive fit and time efficiency, respectively. The significance level was set at P <= *** statistically significant difference was found between group V and group A frameworks regarding passive fit (p-value = 1, OR = 0.5) and time efficiency (P = 0.179, Effect size = 0.948).ConclusionWithin the limitations of this study, it can be concluded that in free end saddle cases, prefabricated CAD\CAM 3-unit implant-supported cobalt chromium screw retained prostheses can achieve an adequate passive fit. However, their fit might be negatively affected in thin ridges and they might require some adjustments.

关键词： binaries: eclipsing   methods: observational   stars: individual (OP Boo and V0511 Cam)  

摘要： This study presented the first light curve analysis of the OP Boo and V0511 Cam binary stars, which was conducted in the frame of the Binary Systems of South and North (BSN) Project. Photometric ground-based observations were conducted with standard filters at two observatories in the Czech Republic. We computed a new ephemeris for each of the systems using our extracted times of minima, TESS data, and additional literature. Linear fits for O-C diagrams of both systems were considered using the Markov Chain Monte Carlo (MCMC) method. The light curves were analyzed using the Wilson-Devinney (WD) binary code combined with the Monte Carlo (MC) simulation. The light curve solutions of both target systems required a cold starspot. The absolute parameters of the systems were calculated by using a P - M parameter relationship. The positions of the systems were also depicted on the Hertzsprung-Russell (HR), P - L, logM(tot) - logJ(0), and T - M diagrams. The hotter component in both systems is determined to be a more massive star. Therefore, it can be concluded that both systems are W-type contact binary systems.

关键词： assistive robotics   human-machine interaction   balance control   movement recovery   vision-transformer   CLIP   cross-attention  

摘要： Introduction Assistive robots and human-robot interaction have become integral parts of sports training. However, existing methods often fail to provide real-time and accurate feedback, and they often lack integration of comprehensive multi-modal *** To address these issues, we propose a groundbreaking and innovative approach: CAM-Vtrans-Cross-Attention Multi-modal Visual Transformer. By leveraging the strengths of state-of-the-art techniques such as Visual Transformers (ViT) and models like CLIP, along with cross-attention mechanisms, CAM-Vtrans harnesses the power of visual and textual information to provide athletes with highly accurate and timely feedback. Through the utilization of multi-modal robot data, CAM-Vtrans offers valuable assistance, enabling athletes to optimize their performance while minimizing potential injury risks. This novel approach represents a significant advancement in the field, offering an innovative solution to overcome the limitations of existing methods and enhance the precision and efficiency of sports training programs.

关键词： ejection fraction reserve   myocardial perfusion imaging   gated SPECT   prognosis   coronary artery disease  

摘要： Purpose: Left ventricular ejection fraction (LVEF) strongly predicts cardiac events. However, conflicting findings exist regarding the prognostic value of the LVEF reserve (Delta LVEF) when measured by gated single-photon emission computed tomography myocardial perfusion imaging (SPECT G-MPI). In particular, data related to the prognostic value of Delta LVEF when measured by SPECT in patients with reduced LVEF are scarce. In this study, we aimed to evaluate the prognostic value of Delta LVEF when acquired by SPECT G-MPI in patients with coronary artery disease (CAD) and a LVEFStress < 60%. Methods: We retrospectively recruited 260 consecutive patients diagnosed with CAD by coronary angiography (CAG) and a LVEFStress < 60%, as determined by SPECT G-MPI. These patients were followed up for 33.4 +/- 7.6 months. The patients were divided into two groups (Delta LVEF > 0% and Delta LVEF <= 0%), and survival analyses were conducted. The primary endpoints were major adverse cardiac events (MACEs), a composite of all-cause death, nonfatal myocardial infarction, unplanned coronary revascularization, and hospitalization for unstable angina. Results: We observed 69 MACEs (26.5%). The cumulative incidence of MACEs in patients with Delta LVEF <= 0% was significantly higher than in patients with Delta LVEF > 0% (P = 0.042). Multivariate Cox regression further revealed that a Delta LVEF <= 0% represented an independent predictor of MACEs (adjusted hazard ratio [HR]: 1.276;95% confidence interval [CI]: (1.006, 1.618), P = 0.045). Adding a Delta LVEF <= 0% to traditional myocardial perfusion and function variables evaluated by MPI significantly improved the ability to predict MACEs (P = 0.044). Conclusions: Determining Delta LVEF by SPECT G-MPI was associated with MACEs and improved risk stratification compared to prediction models based on traditional perfusion and functional parameters in CAD patients with left ventricular dysfunction, particularly those with no or mild myocardial

关键词： Broad learning system   Ensemble learning   Feature engineering   Imbalanced data   Visualization  

摘要： The Broad Learning System (BLS) employs two successive random feature mappings and incorporates ridge regression to construct an efficient classifier. This system achieves performance comparable to Deep Neural Networks, while reducing computational resources. However, BLS exhibits limitations such as a high risk of overfitting, and inadequate robustness to noisy data, which can be addressed through ensemble learning. Nevertheless, traditional ensemble learning models are limited by the lack of interpretability. Therefore, we propose a novel ensemble learning method for BLS with feature selection via Approximate Shapley Value, named Shapley-Value-Based Ensemble Broad Learning System (SE-BLS). Specifically, by analyzing the validation losses of BLS-based weak classifiers, the Approximate Shapley Value is calculated to determine feature contributions and collaborations, which can guide effective feature selection. Based on the reduced features, a regularized classifier is trained for final voting to achieve superior performance on datasets with limited samples and high noise levels. Additionally, a new data weight updating method is introduced for SE-BLS to improve its stability in dealing with imbalanced data. Notably, for image datasets, our method can provide visual analysis of pixel contribution, pixel collaboration, and Class Activation Mapping to enhance interpretability. To validate the performance of the proposed model, we conduct tests on multiple structured and image datasets to assess its classification performance and visualization capabilities. These results are then compared with those of several advanced models. Furthermore, ablation experiments are performed on various aspects of the model's structure to demonstrate its effectiveness. © 2024

关键词： Resin-matrix ceramic   Masking ability   CAD-CAM   Translucency   Thickness   Cement shade   Background color  

摘要： BackgroundTo evaluate the comprehensive effect of translucency, thickness, cement shades, and background color on the masking ability of resin-matrix ceramic veneer restorations. Methods Resin-matrix ceramic specimens with 2 translucencies (LT, HT) and 3 thicknesses (0.5, 1.0, and 1.5 mm) were made of Upcera Hyramic (A2 shade). Cement specimens were made of Variolink N in 4 shades (yellow, white, transparent, and bleach XL). Five background specimens were made of IPS Natural Die Material in 5 shades (ND1, ND2, ND3, ND4, and ND5). Color coordinates of 120 subgroups (n = 5) of combined specimens composed of different ceramic, cement, and background specimens were obtained using a spectroradiometer. Color difference (Delta E-00) compared with a 4-mm thick specimen of LT and HT ceramics was calculated and four-way ANOVA was used for statistical analysis (alpha = 0.05). Results Translucency, thickness, cement shade, background color, and their interaction had significant effects on Delta E-00 (p < 0.001). Delta E-00 values of HT groups were always higher than that of LT groups and were greater than 1.8 against all background colors. Delta E-00 values of LT groups could be achieved to be less than 1.8 with appropriate thickness and cement shade. Delta E-00 value decreased with increasing ceramic thickness. The effect of cement shade on Delta E-00 had no obvious regularity, but Delta E-00 values of bleach XL cement shade group were always lower than other cement shade groups under ND3 and ND5 background color. Conclusions The masking ability of CAD-CAM resin-matrix ceramics can be simultaneously affected by translucency, thickness, cement shade, and background color. Resin-matrix ceramics with low translucency has a better masking ability than that with high translucency. The masking ability of CAD-CAM resin-matrix ceramics increase with increasing thickness. Cement shade has less impact on the final color of resin-matrix ceramic restorations.

摘要： Objectives Cervical artery dissection (CeAD) accounts for 25% of ischemic strokes in young adults. This study evaluated the benefits and harms of intravenous thrombolysis (IVT) in patients presenting with spontaneous CeAD and acute ischemic stroke symptoms. Methods This analysis used data from the retrospective STOP-CAD study and included patients with spontaneous CeAD who presented within 1 day of acute ischemic stroke symptoms. Patients were dichotomized into those who received IVT and those managed without IVT. We assessed the association between IVT and 90-day functional independence (modified Rankin Scale scores 0-2) and the incidence of symptomatic intracranial hemorrhage (ICH, defined as ICH causing new or worsening neurologic symptoms within 72 hours after CeAD diagnosis). Results This study included 1,653 patients from the original STOP-CAD cohort of 4,023. The median age was 49 years, and 35.1% were women;512 (31.0%) received IVT. IVT was associated with 90-day functional independence (adjusted odds ratio [aOR] = 1.67, 95% CI 1.23-2.28, p = 0.001), but not with symptomatic ICH (aOR = 1.52, 95% CI 0.79-2.92, p = 0.215). Discussion In patients with spontaneous CeAD and suspected ischemic stroke, IVT improved functional outcomes, without increasing symptomatic ICH risk. These findings support current guideline recommendations to consider thrombolysis for otherwise eligible patients with CeAD. Classification of Evidence This study provides Class III evidence that IVT significantly increases the probability of 90-day functional independence in patients with CeAD.

关键词： cardiac magnetic resonance   diagnostic criteria   Lake Louise criteria   myocarditis   ACC   American College of Cardiology   AHA   American Heart Association   AM   acute myocarditis   BSA   body surface area   CAD   coronary artery disease   CM   complicated myocarditis   EDV   end-diastolic volume   ECV   extracellular volume fraction   EMB   endomyocardial biopsy   ESC   European Society of Cardiology   HF   heart failure   LGE   late gadolinium enhancement   LLC   Lake Louise criteria   pAM   probable acute myocarditis   VT   ventricular tachycardia  

摘要： The European Society of Cardiology (ESC), the American College of Cardiology, the American Heart Association, and expert consensus documents provide different diagnostic criteria for myocarditis. Their overlap and prognostic value have never been compared.

关键词： Thick blood smears   Coloration quality   Image processing   Machine learning   Malaria diagnosis  

摘要： BackgroundBattling malaria's morbidity and mortality rates demands innovative methods related to malaria diagnosis. Thick blood smears (TBS) are the gold standard for diagnosing malaria, but their coloration quality is dependent on supplies and adherence to standard protocols. Machine learning has been proposed to automate diagnosis, but the impact of smear coloration on parasite detection has not yet been fully *** develop Coloration Analysis in Malaria (CAM), an image database containing 600 images was created. The database was randomly divided into training (70%), validation (15%), and test (15%) sets. Nineteen feature vectors were studied based on variances, correlation coefficients, and histograms (specific variables from histograms, full histograms, and principal components from the histograms). The Machine Learning Matlab Toolbox was used to select the best candidate feature vectors and machine learning classifiers. The candidate classifiers were then tuned for validation and tested to ultimately select the best *** work introduces CAM, a machine learning system designed for automatic TBS image quality analysis. The results demonstrated that the cubic SVM classifier outperformed others in classifying coloration quality in TBS, achieving a true negative rate of 95% and a true positive rate of 97%.ConclusionsAn image-based approach was developed to automatically evaluate the coloration quality of TBS. This finding highlights the potential of image-based analysis to assess TBS coloration quality. CAM is intended to function as a supportive tool for analyzing the coloration quality of thick blood smears.

关键词： Cad/cam   Post-crown   Endocrown   Fracture strength  

摘要： Background This study evaluates the fracture strength and patterns of feldspathic porcelain restorations made using CAD/CAM technology for lower first molars with extensive crown destruction. The restorations include post-core and full-contour crown, composite resin core and full-contour crown, and endocrown. This research provides insights into effective restorative options to address tooth fracture risk, supporting minimally invasive procedures and CAD/CAM integration in dental practices. Methods This study utilized 80 permanent mandibular first molars, which were divided into four groups: Group I (Post-Core-Full-contour crown), Group II (Core- Full-contour crown), Group III (Endocrown), and Group IV (Control). Root canal treatment was performed on all samples except for the control group. Following access cavity preparation, restorations for each tooth were fabricated using the CAD/CAM system and cemented with resin cement. The specimens were embedded in acrylic blocks. After undergoing thermomechanical aging, the samples were subjected to fracture resistance testing using a universal testing machine, which applied force until fracture occurred. The fracture patterns were subsequently analyzed, and the data were statistically evaluated using the Kruskal-Wallis and Chi-Square tests (p < 0.05). Results A significant difference in fracture values under axial forces was observed (p < 0.05). The control group had the highest fracture strength (1830 +/- 277 N), while the Core- full-contour crown group showed the lowest (1532 +/- 371 N). Failure types varied significantly among the groups (chi 2 = 26.886, df = 9, p = 0.001). The most common failure type was Type-2 (33.75%), characterized by restorable fractures, while Type-3 fractures, unrestorable, were the least common (12.5%). Conclusions The findings underscore the significance of technological advancements in CAD/CAM for effectively restoring endodontically treated teeth with extensive crown damage. This study cont