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关键词： Resin-based luting agent   CAD-CAM blocks   Wear   Hardness  

摘要： This study aimed to investigate the wear and microhardness of luting agents and computer-aided design-computer-aided manufacturing (CAD-CAM) resin blocks, and to compare the wear characteristics of resin-based luting agents used in bonded specimens of CAD-CAM resin blocks. After three-body wear test, the amount of wear and Vickers hardness were measured and Pearson's correlation coefficient was calculated. The lowest amount of wear and the highest Vickers hardness values were obtained for Estecem II. Filler loss was observed in five composite resin cements. A strong negative correlation was observed in the luting agents between the amount of wear and Vickers hardness value (r=-0.874, p<0.0001). Additionally, a strong positive correlation was observed between the amount of wear of the bonded specimen and amount of luting agent used alone (r=0.943, p<0.0001). To conclude, the wear resistance of the luting agent used in the bonded specimen was significantly influenced by the bonding between the filler and matrix resin.

关键词： Tan Trieu   Duong La Cam pomelo   naringin   antioxidant   antibacterial  

摘要： Objective Naringin was known to be a flavonoid compound with many biological activities and was present in pomelo peel. Duong La Cam pomelo was a speciality grapefruit in Tan Trieu commune, Vinh Cuu district, Dong Nai province. This study evaluated Duong La Cam pomelo extract's naringin content and antioxidant and antibacterial *** Duong La Cam pomelo extract was extracted by ultrasonic method. Naringin content was determined based on the naringin standard curve. Biological activities were evaluated by DPPH, ABTS, Agar disk-diffusion method and The minimum inhibitory concentration (MIC).Results The research results of enriching the Naringin component in the Duong La Cam Pomelo extract were recorded with a content of 114 mg/gDW. Duong La Cam Pomelo extract was extracted by ultrasonic method with solvent and raw material ratio 1 g/10 mL, time 60 min, temperature 70 degrees C and using 80% Ethanol solvent. The results showed antioxidant capacity with IC50 values of 0.127 mg/mL (ABTS);14 511 mg/mL (DPPH). Besides, the antibacterial ability of the sample was also recorded at the minimum inhibitory concentration of Escherichia coli of 2.5 mg/mL and Staphylococcus aureus of 5 mg/*** The study showed that the ultrasonic extraction method saves time but still ensures high naringin content and good activity in extraction. It can be seen that naringin extract from Duong La Cam grapefruit has great potential for application in the medical field.

关键词： Memristors  

摘要： Abstract: This paper uses LTspice, a potent electronic circuit simulation tool, to integrate memristors into circuits for static random access memory (SRAM), presenting a novel technique for building content addressable memory (CAM) cells. Memory devices are essential in developing complex digital logic circuits and integrated circuits. Such memory circuits will be built using static random access memories and content addressable memory cells with the help of memristors. Memristors offer nonvolatile storage capabilities, while CAM cells enable quick retrieval of content-based data. We describe the design approach in detail, emphasizing how LTspice’s simulation and optimization procedures allow seamless Memristor integration. Compared to conventional CAM cell designs, experimental simulations show enhanced performance parameters, including speed, power consumption, and area overhead. This work highlights LTspice’s potential as a valuable instrument for CAM cell technology advancement, boosting effectiveness and dependability in contemporary computing systems. © Pleiades Publishing, Ltd. 2024.

关键词： artificial intelligence   Eigen-CAM   X-ray   analysis   YOLOv8  

摘要： This study is an artificial intelligence (AI)-supported system that aims to help dentists and students by analyzing dental X-rays and detecting certain diseases in teeth. This system aims to help students in the learning process by quickly detecting procedures such as dentin decay, root canal treatment, implants, crowns, fillings in dental X-rays. The datasets obtained through Roboflow were subjected to labeling process. The dataset consists of approximately 2500 dental X-ray images containing dental diseases and procedures performed on teeth, consisting of 5 different classes. The classes identified in these images were labeled. After this labeling process, a deep learning model was developed using YOLOv8 architecture. Eigen-CAM was added to the model and its performance was tested. Eigen-CAM helped to finalize the results of the model by visualizing them. After all these processes, the model was integrated into a web interface and made available for use. The results of this study show that the proposed method is very fast and effective in analyzing dental X-rays. The results of the study have made significant contributions to dentists and dental students in terms of early diagnosis and learning process and have the potential to positively affect clinical decision support processes.

关键词： ginsenoside Re   forced degradation products   charged aerosol detector   LC-HRMS   mass fragmentation pathway   toxicity  

摘要： Ginsenoside Re was the major bioactive component found rich in Panax ginseng C. A. Meyer, which exerted excellent cardiovascular protection, anti-inflammatory, and anti-oxidation effects. The generation of unexpected degradation products (DPs) may influence the therapeutic effect of Re, or even bring toxic effects to patients. However, to date, only a few reports were available about the stability of Re. The present study aims to systematically investigate the degradation behaviors of Re under different stress conditions, including hydrolysis (acidic, basic, and neutral), oxidation, humidity, thermal, and photolytic (ultraviolet and visible light) conditions. A total of thirteen DPs were putatively identified, and among them, nine were discovered for the first time in our study. The results showed that Re was sensitive to exposure to acidic, basic, and oxidation conditions. It underwent a series of chemical degradation reactions, including deglycosylation, dehydration, addition, oxidation at the double bond, and isomerization under various stress conditions. Structural characterization of these DPs was carried out by UHPLC-DAD-CAD and LC-LTQ/Orbitrap. A plausible mechanism of their formation was proposed to support the structures of all DPs of Re. In silico toxicity prediction and metabolism behavior assessment were done by Derek Nexus and Meteor Nexus software. Re and DP-1 to DP-6 were predicted to possess potential skin irritation/corrosion toxicity. DP-11 and DP-12 bear the potential for carcinogenicity, mutagenicity, irritation, hepatotoxicity, and skin sensitization. The observation of these DPs updates our knowledge regarding the stability of Re, which provides valuable information for quality control and to choose suitable storage conditions.

关键词： CAD/CAM   ceramics   crown   marginal fit  

摘要： This study aimed to evaluate the scanning time and marginal fit of CAD/CAM crowns fabricated using different intraoral scanning systems (IOS) (O1-Omnicam 1.0, O2-Omnicam 2.0, PS-Primescan). A standardized, 3D-printed composite resin die with a full-crown tooth preparation was scanned ten times with each IOS, and the scanning time was recorded. Subsequently, lithium disilicate ceramic crowns were designed and milled. The crowns were seated in the die and scanned using micro-computed tomography to assess the marginal fit. Fifty-two measurements were performed for each crown. Data were assessed for homogeneity, and one-way analysis of variance and the Tukey HSD test were performed (alpha = 0.05). For the analysis of vertical fit categories, the chi-square (Fisher's exact) test (alpha = 0.05) was used. The mean vertical fit values were: O1-46.7 +/- 16.4 mu m, O2-33.8 +/- 21.4 mu m (p = 0.041), and PS-12.3 +/- 6.6 mu m (p < 0.001). The vertical fit values were further categorized by percentage and representative specimens were scanned with electron microscopy to evaluate adaptation. The mean scanning times were: O1-37.4 +/- 3.1 s;O2-34.8 +/- 2.7 s;and PS-27.8 +/- 1.9 s. Significant differences were observed in the scanning times and marginal fit values of the CAD/CAM ceramic crowns across the different IOS systems, with PS demonstrating the best results. Improvements in IOS hardware and software significantly influence these outcomes.

关键词： Action recognition   game theory   human skeleto   Monte Carlo sampling   spatial-temporal graph convolution network  

摘要： Graph Convolutional Networks (GCN) have shown outstanding performance in skeleton-based behavior recognition. However, their opacity hampers further development. Researches on the explainability of deep learning have provided solutions to this issue, with Class Activation Map (CAM) algorithms being a class of explainable methods. However, existing CAM algorithms applies to GCN often independently compute the contribution of individual nodes, overlooking the interactions between nodes in the skeleton. Therefore, we propose a game theory based class activation map for GCN (GT-CAM). First, GT-CAM integrates Shapley values with gradient weights to calculate node importance, producing an activation map that highlights the critical role of nodes in decision-making. It also reveals the cooperative dynamics between nodes or local subgraphs for a more comprehensive explanation. Second, to reduce the computational burden of Shapley values, we propose a method for calculating Shapley values of node coalitions. Lastly, to evaluate the rationality of coalition partitioning, we propose a rationality evaluation method based on bipartite game interaction and cooperative game theory. Additionally, we introduce an efficient calculation method for the coalition rationality coefficient based on the Monte Carlo method. Experimental results demonstrate that GT-CAM outperforms other competitive interpretation methods in visualization and quantitative analysis.

关键词： Coronary arteries   Heart   Hemorrhage   Mortality   Percutaneous coronary intervention   Revascularization   Signs and symptoms   Stable coronary artery disease   Stenosis  

摘要： AbstractSource CitationLønborg J, Jabbari R, Sabbah M, et al; NOTION-3 Study Group. PCI in patients undergoing transcatheter aortic-valve implantation. N Engl J Med. 2024 Aug 31. [Epub ahead of print.] https://***/39216095/AbstractClinical Impact RatingsGIM/FP/GP: Cardiology:

关键词： Salidroside   Aglycones   Endothelial cell   Hypoxia/hypothermia   eNOS/NO  

摘要： To investigate vascular endothelium damage in rats exposed to hypoxic and cold and the effect of salidroside in protecting against this damage. A rat isolated aortic ring hypoxia/cold model was established to simulate exposure to hypoxic and cold. The levels of endothelial cell injury markers were measured by ELISA. TEM was performed to observe the ultrastructure of vascular ring endothelial cells. In vitro assays were performed to verify the effect of salidroside on endothelial cells. CCK-8 and flow cytometry were performed to analyze endothelial cell survival and apoptosis, respectively. Ca2+ concentrations were measured by Flow cytometry, and the expressions of NOS/NO pathway-related proteins were measured by WB. Endothelial cell damage, mitochondrial swelling, autophagy, and apoptosis were increased in the hypoxia group and hypoxia/hypothermia group. All of these effects were inhibited by salidroside. Moreover, exposure to cold combined with hypoxia reduced the NO levels, Ca2+ concentrations and NOS/NO pathway-related protein expression in the hypoxia group and hypoxia/hypothermia group. Salidroside treatment reversed these changes. Salidroside protected against endothelial cell injury induced by cold and hypoxia through reduction of Ca2+-CaM-CAMKII-dependent eNOS/NO activation, thereby preventing mitochondrial damage, reducing ROS levels, and inhibiting apoptosis.

关键词： bone biopsies   bone regeneration   CAD/CAM mesh   micro-CT   randomized clinical trial   resorbable membrane  

摘要： Objectives: To date, no studies have exploited micro-CT in humans to evaluate bone morphology and structure after bone augmentation with CAD/CAM-customized titanium mesh, in mandible and maxilla. The aim of this study was to assess the composition and microstructure of bone biopsy through micro-CT analysis. Materials and Methods: Bone augmentation at both maxillary and mandible sites was performed on 30 patients randomly treated with customized mesh, either alone (M-) or covered with resorbable membrane (M+), in both cases filled 50:50 with autogenous bone and xenograft. After 6 months, biopsies were taken and micro-CT was performed on consecutive 1-mm-thick VOIs from coronal to apical side, measuring tissue volumes, trabecular thickness, spacing, and number. Results: In both groups, irrespective of membrane use, bone tissue (M-: 29.76% vs. M+: 30.84%) and residual graft material (M-: 14.87% vs. M+: 13.11%) values were similar. Differences were site-related (maxillary vs. mandibular) with higher percentage of bone tissue and trabecular density of low-mineralized bone and overall bone in the mandible. Conclusions: The composition and structure of bone tissue, as assessed by micro-CT after alveolar ridge augmentation using CAD/CAM-customized titanium meshes, showed similar features regardless of whether a collagen membrane was applied.