Search Results (82)

Background. Physicomechanical properties and clinical service of bulk-fill composites depend on their adequate polymerization and depth of cure. Some manufacturers claim that these composites can be adequately cured when used in bulks exceeding 4 mm. Objective. The aim of this study was to compare Vickers microhardness (VMH) and depth of cure (DOC) of six contemporary bulk-fill resin composites at depths of 4 mm and 6 mm. Material and methods. Six bulk-fill composites were evaluated in this study: 1. Tetric EvoCeram Bulk (Ivoclar Vivadent, Schaan, Liechtenstein), (TEC); 2. Filtek Bulk Fill Posterior (3M ESPE Dental Products Division, St. Paul, MN, USA), (FBF); 3. Filtek One Bulk Fill (3M ESPE Dental Products Division, St. Paul, MN, USA, (FOB); 4. SonicFill 2 (Kerr, Orange, CA, USA), (SF2); 5. Admira Fusion X-tra (Voco, GmbH, Cuxhaven, Germany), (AFX); 6. GrandioSO X-tra (Voco, GmbH, Cuxhaven, Germany), (GSX). The 18 specimens (3 of each composite) were prepared in split Teflon moulds of 4 mm diameter and 6 mm thickness. All composites were cured in standard mode for 20 s using LED LCU (D-Light Duo, RF-Pharmaceuticals Sarl, Geneva, Switzerland; 1200–1300 mW/cm). The VMH was measured using a digital Micro Hardness Tester Shimadzu (HMV-2T E, Shimadzu Corporation, Kyoto, Japan). A 50 g (0.5 N) load force was applied for 30 s. Each specimen was measured at five places selected by chance at each level (N = 15). The hardness ratio or DOC was calculated for all samples as the ratio of bottom and surface microhardness at levels of 4 and 6 mm. Data were analysed using one-way ANOVA and Tukey’s post hoc test. Results. Significant reduction in VMH was observed for all tested materials when comparing top surface and bottom (p < 0.01). The highest VMH was obtained for GSX and AFX, and the lowest for TEC. The results show that the degree of polymerization was adequate for all tested materials at a depth of 6 mm, since the hardness ratio exceeded 0.80 in all cases. The hardness ratio at 4 mm was high for all tested composites ranging from 0.91 for TEC to 0.98 for GSX. All composites showed adequate DOC at the bottom of the 6 mm bulk samples. However, the hardness ratio was the highest for Admira Fusion X-tra (0.96) and GrandioSO X-tra (0.97). Conclusions. All tested materials showed a significant decrease in microhardness from the top surface to the bottom. The DOC was adequate for all bulk-fill composites at a depth of 6 mm cured under standard mode for 20 s. All bulk-fill resin composites evaluated in this study can be used in bulk, up to 6 mm. Full article

Accurate diagnosis of gastrointestinal (GI) diseases typically requires invasive procedures or imaging studies that pose the risk of various post-procedural complications or involve radiation exposure. Bowel sounds (BSs), though typically described during a GI-focused physical exam, are highly inaccurate and variable, with low clinical value in diagnosis. Interpretation of the acoustic characteristics of BSs, i.e., using a phonoenterogram (PEG), may aid in diagnosing various GI conditions non-invasively. Use of artificial intelligence (AI) and improvements in computational analysis can enhance the use of PEGs in different GI diseases and lead to a non-invasive, cost-effective diagnostic modality that has not been explored before. The purpose of this work was to develop an automated AI model, You Only Listen Once (YOLO), to detect prominent bowel sounds that can enable real-time analysis for future GI disease detection and diagnosis. A total of 110 2-minute PEGs sampled at 44.1 kHz were recorded using the Eko DUO^® stethoscope from eight healthy volunteers at two locations, namely, left upper quadrant (LUQ) and right lower quadrant (RLQ) after IRB approval. The datasets were annotated by trained physicians, categorizing BSs as prominent or obscure using version 1.7 of Label Studio Software^®. Each BS recording was split up into 375 ms segments with 200 ms overlap for real-time BS detection. Each segment was binned based on whether it contained a prominent BS, resulting in a dataset of 36,149 non-prominent segments and 6435 prominent segments. Our dataset was divided into training, validation, and test sets (60/20/20% split). A 1D-CNN augmented transformer was trained to classify these segments via the input of Mel-frequency cepstral coefficients. The developed AI model achieved area under the receiver operating curve (ROC) of 0.92, accuracy of 86.6%, precision of 86.85%, and recall of 86.08%. This shows that the 1D-CNN augmented transformer with Mel-frequency cepstral coefficients achieved creditable performance metrics, signifying the YOLO model’s capability to classify prominent bowel sounds that can be further analyzed for various GI diseases. This proof-of-concept study in healthy volunteers demonstrates that automated BS detection can pave the way for developing more intuitive and efficient AI-PEG devices that can be trained and utilized to diagnose various GI conditions. To ensure the robustness and generalizability of these findings, further investigations encompassing a broader cohort, inclusive of both healthy and disease states are needed. Full article

Acoustic tomography is a non-destructive technique used in the internal assessment of standing trees. Various researchers have focused on developing analytical tools using this technique, demonstrating that they can detect internal biodeterioration in cross-sections with good accuracy. This study evaluates the use of two ultrasonic wave devices with different frequencies (USLab and Sylvatest Duo) and a stress wave device (Microsecond Timer) to generate acoustic tomography using ImageWood VC1 software. The tests were carried out on 12 cross-sections of urban trees in the city of Madrid of the species Robinia pseudoacacia L., Platanus × hybrida Brot., Ulmus pumila L., and Populus alba L. Velocity measurements were made, forming a diffraction mesh in both standing trees and logs after cutting them down. An inspection was carried out with a perforation resistance drill (IML RESI F-400S) in the radial direction in each section, which allowed for more precise identification of defects and differentiating between holes and cracks. The various defects were determined with greater accuracy in the tomographic images taken with the higher-frequency equipment (45 kHz), and the combination of ultrasonic tomography and the use of the inspection drill can provide a more accurate representation of the defects. Full article

This study investigates how moisture preconditioning and thermal parameters affect the stretchability of paper in 3D forming, with the goal of extending geometric forming limits and enhancing process stability. Multidimensional tensile tests were performed on FibreForm Duo (310 g/m²) using a hemispherical punch. Key variables included water bath dwell time, punch temperature, and contact time, simulating industrial conditions in high-speed packaging. A short duration of water bath immersion (1–3 s) led to rapid moisture uptake (−20%), resulting in significantly improved formability. Compared to unconditioned samples, the maximum stretch increased by up to 3.5 percentage points. The process window identified (3.03 s dwell time; 70 °C punch temperature; 1.08 s contact time to punch) yielded a predicted stretch of 16.5%, representing a notable expansion of the material’s geometric forming capacity. Regression analysis (R² = 0.8946) confirmed the strong statistical significance of all parameters. Full article

Technological advancements have led to the development of various devices designed to monitor training loads and athletic performance. Power meters, particularly in cycling, allow for the precise quantification of power output, which is crucial for managing training loads and evaluating performance improvements. This study evaluates the validity of the Quarq D-Zero power meter for measuring cycling power output by comparing it with two previously validated devices—the Favero Assioma Duo (FAD) and the Hammer Saris H3 (H3)—noting that, although it shares the same measurement location as the SRM (the gold standard), it has not been directly validated against it. Thirty-one trained male cyclists participated in this study, undergoing tests across various power outputs (100–500 W) and three 10-s sprint efforts. The protocol incorporated different cadences (70, 85, and 100 revolutions per minute), randomized in order, and two cycling positions (seated and standing). Significant differences (p < 0.05) in power readings were observed among the three power meters, except during sprint efforts. However, pairwise comparisons revealed no significant differences (p > 0.05) between the FAD and Quarq power meters, except for the 500 W block. Strong to very strong correlations were observed between the FAD and Quarq power meters (r > 0.883, ICC > 0.879). The coefficient of variation (CV) between the FAD and Quarq devices ranged from 0.62% to 4.89%, and from 0.39% to 6.59% between the H3 and Quarq power meters. In conclusion, the Quarq power meter, integrated into the spider of the bicycle’s bottom bracket, provides valid power output measurements in cycling. Full article

The article presents the results of experimental studies on the symmetrical and asymmetrical rolling process of composite laminate sheets consisting of difficult-to-deform Ti and Ni materials. Composite sheets joined by explosive welding were used for the tests. The aim of the research was to determine the impact of plastic shaping conditions in the rolling process on the quality and selected functional properties of the materials constituting the layered composite. The rolling process was carried out cold on a duo laboratory rolling mill with a roll diameter of 300 mm. During the rolling process, the influence of the rolling process conditions on the distribution of metal pressure forces on the rolls was determined, as well as the shear strength and microstructural studies of the joint area of the layered composites. As part of the conducted considerations, residual stress tests were carried out using the Barkhausen noise method. The scientific aim of the presented work was to determine the optimal conditions for the plastic processing of multi-layer Ti-Ni sheets. The results presented in the work allowed for determining the most favorable conditions for the rolling process. Full article

The United States is facing outbreaks of highly pathogenic avian influenza H5N1 in birds and dairy cattle, along with threats of African swine fever, classical swine fever, and foot-and-mouth disease. While the National Animal Health Laboratory Network (NAHLN) depends on high-throughput testing, the KingFisher Duo Prime, IndiMag 48s, and IndiMag 2 are viable alternatives to aid in outbreak assessments. This study evaluates extraction platforms and the IndiMag Pathogen Kit for detecting the previous listed pathogens. Samples and reference materials were extracted using the MagMAX Viral RNA Isolation Kit, MagMAX CORE Nucleic Acid Purification Kit, and IndiMag Pathogen Kit. Real-time RT-PCR was performed following NAHLN protocols to assess analytical and diagnostic performance. Comparable limits of detection across extraction chemistries, instrumentation, and pathogens were demonstrated, with PCR efficiency ranging between 82.5% and 107.6%. The precision variability was low, with the coefficient of variation ranging from 0.16% to 1.76%. Diagnostic sensitivity and specificity were 100%, with a kappa coefficient of 1.0, indicating strong agreement between methods. These findings support the KingFisher Duo Prime, IndiMag 48s, IndiMag 2, and IndiMag Pathogen Kits as reliable options for NAHLN-approved testing, increasing equipment and reagent alternatives to enhance diagnostic resilience and improve response capabilities to emerging animal health threats. Full article

Objective: The purpose of this investigation was to assess and compare the internal adaptation of different distinct CAD (Computer-aided design)/CAM (Computer-aided manufacturing) endocrown materials: feldspathic porcelain, indirect composite, hybrid ceramic, reinforced lithium disilicate, and lithium disilicate, utilizing microcomputed tomography. Methods: Standardized endocrown restorations were fabricated for mandibular first molar models. A total of seventy-five restorations were evenly allocated into five groups (n = 15 each): Group I (Cerec Blocks), Group II (Lava Ultimate), Group III (PICN Vita Enamic), Group IV (Celtra Duo), and Group V (Cerec Tessera). The restorations were bonded using PANAVIA V5 adhesive resin cement. To evaluate internal adaptations within the restorations, three distinct locations were selected for the acquisition of high-resolution micro-CT scans: the margin, the axial wall, and the pulpal floor. Data were analyzed using SPSS. To identify statistically significant differences among groups, a two-way ANOVA was conducted, followed by post hoc Tukey tests. Results: The statistical analysis did not reveal significant differences in internal gap measurements across the various material groups (p = 0.055). However, significant variations were observed within individual material groups (p < 0.001) at distinct locations, with the most pronounced discrepancies in thickness evident at the pulpal floor. Conclusion: While no significant differences were observed in internal adaptations among the various endocrown materials, substantial intra-group variability, particularly in terms of pulpal floor thickness, was evident. Since the study maintained a consistent preparation design across all groups, the observed variations in internal adaptation are likely attributed to differences in material behavior rather than changes in preparation geometry. Full article

The widespread implementation of new CAD/CAM materials has led to the necessity of establishing an adequate luting protocol. The aim of this study was to evaluate the microtensile bond strength (μTBS) and the film thickness of different luting methods on CAD/CAM resin blocks. Five Brilliant Crios CAD/CAM blocks (Coltene/Whaledent) were sequentially sectioned into two halves, air abraded with 50 µm aluminum oxide, and luted according to five different cementation protocols: Brilliant EverGlow (BEG), Brilliant EverGlow with ultrasound application (BEG-US), preheated Brilliant EverGlow (BEG-H), Brilliant EverGlow Flow (BEGF), and Duo Cem^® Trans (DC). Subsequently, the blocks were sectioned to obtain rods, which were then submitted to a microtensile bond strength test (n = 20). The surfaces were examined with optical microscopy to determine the failure mode and the bonding interface was assessed with scanning electron microscope (SEM) analysis. Bond strength values were analyzed using one-way ANOVA and Tukey’s post hoc tests (α = 0.05). The bond strength values varied with the different cementation protocols (p < 0.001): BEG (45.48 ± 18.14 MPa), BEG-US (42.15 ± 14.90 MPa), BEG-H (41.23 ± 15.15 MPa), BEGF (58.38 ± 15.65 MPa), and DC (81.07 ± 8.75 MPa). Regarding bond strength, DC presented significantly higher values than all other experimental groups (p < 0.050), whereas all luting methods using BEG presented similar values (p = 0.894). Adhesive failures were the predominant type. On SEM evaluation, all the luting materials presented a tight and homogeneous cement–block interface with variable film thicknesses. In conclusion, among the cementation protocols, the resin cement (DC) rendered the highest bond strength values. SEM analysis revealed that the lowest film thickness was associated with the flowable composite (BEGF). Full article

Heated tobacco products (THPs) are increasingly promoted as potential harm reduction tools, offering an alternative to traditional cigarettes. Despite these claims, understanding of their toxicological impact on respiratory health and associated microbial communities is limited. Comprehensive investigations are needed to elucidate the biological mechanisms and potential health implications associated with their use. Methods: This study evaluated the toxicological effects of aerosols produced by THPs (IQOS 3 Duo with Heets “Sienna Selection”) in comparison to conventional cigarette smoke (1R6F). Antibacterial activity was evaluated using Streptococcus pneumoniae and Klebsiella pneumoniae as representative species of the respiratory microbiota through agar diffusion assays and MIC/MBC determinations. Cytotoxicity was assessed in human lung fibroblast cells (MRC5) through the neutral red uptake (NRU) assay, whereas mutagenicity was investigated using the Ames test. Results: THP aerosols demonstrated the ability to inhibit the growth of both S. pneumoniae and K. pneumoniae, exerting bacteriostatic effects at lower concentrations and bactericidal effects at higher concentrations. While these antibacterial effects might initially seem beneficial against pathogens such as K. pneumoniae, they raise concerns about the potential disruption of the respiratory microbial balance, particularly in relation to S. pneumoniae. Despite these microbiological effects, THP aerosols demonstrated minimal cytotoxicity on human lung fibroblasts and lacked detectable mutagenic activity, contrasting with the significant cytotoxicity and mutagenicity caused by cigarette smoke. Conclusions: THPs present a reduced short-term toxicological profile compared with conventional cigarettes; however, their effects on respiratory microorganisms deserve attention. The observed inhibition of commensal bacteria highlights the need to explore potential changes in the microbial ecosystem that could affect respiratory health. These findings highlight the need for additional studies to evaluate the long-term effect of THP use on respiratory microbiota and the stability of the overall microbial ecosystem. Full article

The replacement of historical load-bearing wooden elements made from not commonly used species such as Populus tremula L. presents significant challenges. As these species are seldomly used in modern construction, a knowledge gap exists regarding their implementation in accordance with current building codes. This study investigates the mechanical properties of European aspen (Populus tremula L.) from central Slovakia as a potential replacement for historical structures. Notably, poplar species, including European aspen, have historically been utilized for construction across various landscapes in Europe. We conducted experimental testing on visually graded aspen timber to determine the dynamic modulus of elasticity (MOE_dyn,ultr), modulus of elasticity (MOE), modulus of rupture (MOR), and density. The results were analyzed and compared to established standards for structural timber. Notably, the 5th percentileof the strength distribution (f_0.05) was determined to be 28.78 MPa, while the characteristic strength (f_k) was 26.23 MPa, and the modulus of elasticity (E_g12) was 13.60 MPa. The correlation between MOR and dynamic MOE facilitated the determination of MOR by non-destructive testing (NDT) using the Sylvatest Duo^®. This simple linear model could grade 49% of boards into the higher strength class C30. The additional parameters and their interactions in multiregresssion models improved the predictability of the bending strength of aspen. The advanced model graded 68% of boards into C30. These characteristics, along with aspen’s growth potential, make it a promising candidate for replacing damaged structural elements in historical constructions. Our findings contribute to the understanding of the potential of European aspen as a structural timber, highlighting its viability as a fast-growing hardwood species. Full article

Feline leukemia and feline immunodeficiency virus infections are two widespread diseases that affect the health of domestic cats all over the world. In Algeria, despite the existence of a large population of cats, there are no published data regarding the epidemiological status of feline retroviruses. Therefore, the objective of the present study was to estimate the seroprevalence of FIV and FeLV infections in cats in Algiers and to assess the main factors associated with the infection. A cross-sectional study was conducted in which 71 cats were sampled from several private veterinary clinics, and their obtained sera were tested using an immunochromatography analysis (SNAP Duo FIV/FeLV Test; Virbac Laboratories, France). The seroprevalence was about 32.39% and 22.53% for FIV and FeLV, respectively. Overall, 11.26% were positive for both infections. The present study showed that FIV seropositivity was associated with a younger age and health status (p < 0.05), while FeLV seropositivity was associated with the sex, reproductive status, housing, age, and health status of the cats. This preliminary study, which utilized rapid tests, provides important initial data revealing a relatively high prevalence of retroviruses in cats in Algeria. The results underscore the urgent need for implementing both preventive and management measures to control the spread of these retrovirus diseases. However, to enhance the reliability of future findings, it is essential to expand the sample size and incorporate reference diagnostic methods. Full article

Drug-coated balloons (DCBs) have emerged as an increasingly valuable option for the treatment of coronary artery disease (CAD). Percutaneous coronary intervention (PCI) with DCBs enables the localized delivery of antiproliferative drugs directly to the target coronary lesion, avoiding the need for permanent scaffold implantation. Historically, paclitaxel-coated balloons (PCBs) have been the most used device in this context. Paclitaxel interferes with intracellular microtubule function, leading to cell cycle arrest. However, its cytotoxicity at a higher dosage and narrow therapeutic range has raised some safety concerns. To address these issues, sirolimus-coated balloons (SCBs) have been introduced as an alternative. Sirolimus acts as a cytostatic agent with potent anti-inflammatory and antiproliferative properties and is characterized by a wider therapeutic range, potentially offering a safer profile. Several experimental and clinical studies comparing the safety and efficacy of PCBs versus SCBs have yielded mixed results. Recently, a novel DCB (SirPlux Duo), which simultaneously releases both paclitaxel and sirolimus, has been tested in a porcine coronary model with promising results. In this review, we will elucidate the mechanisms of action of paclitaxel and sirolimus, examine contemporary preclinical and clinical evidence comparing PCB and SCB angioplasty, and discuss novel devices that may enhance the safety and efficacy of PCI with DCBs. Full article

The aim of this study is to present the characteristics and a comparison of four different commercial materials dedicated to the CAD/CAM technique in dentistry, all of which can be classified as ceramic materials. Its purpose is also to evaluate the impact of surface treatment on the cytotoxicity and microbiological properties of the materials. The CAD/CAM technique has a perpetually growing role in modern reconstructive dentistry. It requires a material’s possession of peculiar characteristics, such as mechanical resistance, durability, functionality (similar to natural tissues), good aesthetics and biocompatibility. To critically evaluate a biomaterial, both manufacturer claims and in vitro tests should be considered. Further steps of evaluation may include animal tests and clinical trials. There are certain attributes of biomaterials that may be modified by surface treatment that can be crucial to the clinical success of the material. The evaluated materials were Vita Suprinity (VITA-Zahnfabrik, Germany), Vita Mark II (VITA-Zahnfabrik, Germany), Celtra Duo (Dentsply Sirona, USA) and Empress Cad (Ivoclar Vivadent, Liechtenstein). They are available in the form of prefabricated blocks of various diameters and are popular among operators performing clinical procedures using CAD/CAM. Standardized blocks of each material were prepared. Half of them had their surface polished. Further, half of all the samples were covered by a nano-copper layer. The samples were evaluated for cytotoxicity, presented on a 0–4 scale, adhesion susceptibility and potential of forming a biofilm on their surface. Physicochemical properties such as the water contact angle (WCA) were evaluated for the tested materials. The influence of copper coating on cytotoxicity cannot be unequivocally stated or denied. Surface polishing did not affect the materials’ cytotoxicity, but it increased the WCA of all materials and, therefore, their hydrophobicity. Different degrees of adhesion ability and biofilm formation were dependent on the species of microorganisms and properties of the dental materials. Full article

The fish detection task is an essential component of marine exploration, which helps scientists monitor fish population numbers and diversity and understand changes in fish behavior and habitat. It also plays a significant role in assessing the health of marine ecosystems, formulating conservation measures, and maintaining biodiversity. However, there are two main issues with current fish detection algorithms. First, the lighting conditions underwater are significantly different from those on land. In addition, light scattering and absorption in water trigger uneven illumination, color distortion, and reduced contrast in images. The accuracy of detection algorithms can be affected by these lighting variations. Second, the wide variation of fish species in shape, color, and size brings about some challenges. As some fish have complex textures or camouflage features, it is difficult to differentiate them using current detection algorithms. To address these issues, we propose a fish detection algorithm—FishDet-YOLO—through improvement in the YOLOv8 algorithm. To tackle the complexities of underwater environments, we design an Underwater Enhancement Module network (UEM) that can be jointly trained with YOLO. The UEM enhances the details of underwater images via end-to-end training with YOLO. To address the diversity of fish species, we leverage the Mamba model’s capability for long-distance dependencies without increasing computational complexity and integrate it with the C2f from YOLOv8 to create the Mamba-C2f. Through this design, the adaptability in handling complex fish detection tasks is improved. In addition, the RUOD and DUO public datasets are used to train and evaluate FishDet-YOLO. FishDet-YOLO achieves mAP scores of 89.5% and 88.8% on the test sets of RUOD and DUO, respectively, marking an improvement of 8% and 8.2% over YOLOv8. It also surpasses recent state-of-the-art general object detection and underwater fish detection algorithms. Full article