Search Results (1,285)

Background: The purpose of this study was to examine the relationship between qualitative characteristics and quantitative parameters from contrast-enhanced ultrasound (CEUS) and microvessel density (MVD) in hepatoblastoma (HB), as well as to investigate whether CEUS could be utilized as a non-invasive method for predicting HB progression. Methods: This retrospective analysis was carried out in one medical center and included 34 children with histopathologically confirmed HB. Both grayscale ultrasound and CEUS results were reviewed. Lesions were evaluated using time–intensity curve (TIC) analysis software to extract quantitative parameters. Postoperative tissue specimens were stained with CD34 immunohistochemistry, and MVD was quantified as the reference standard. Statistical analyses were conducted to assess the correlation between CEUS findings and MVD. Results: Lesions were separated into high (n = 21, 61.76%; MVD ≥ 41) and low (n = 13, 38.24%; MVD < 41) MVD groups, using the median microvessel density of 41 vessels per high-power field (HPF) as the cutoff. High MVD lesions exhibited a significantly higher incidence of penetrating vessels compared with low MVD lesions (p < 0.05). Elevated MVD levels were significantly associated with increased Adler-grade blood flow (p < 0.05). Both TIC-derived and relative quantitative parameters exhibited significant intergroup differences. Among the relative parameters, the relative wash-out rate (rWoR) was significantly higher in the low MVD group (p < 0.05). Moreover, the Receiver Operating Characteristic (ROC) curve analysis indicated that an rWoR threshold of ≥1.36 could serve as a predictor for low MVD, resulting in 76.9% sensitivity and 81.0% specificity (AUC = 0.802; 95% CI: 0.634–0.970; p = 0.003). Conclusions: CEUS revealed an association with MVD, supporting its potential as a non-invasive tool to characterize tumor vascularity. Full article

Permeability evolution is one of the key parameters influencing the efficient exploitation of deep unconventional energy resources, as it reflects the dynamic development of pore-fracture structures under complex engineering effects. Using fractal geometry to describe the pore-fracture system, rock permeability enhancement can be quantitatively evaluated. In this study, fractured coal specimens were analyzed under simulated mining-induced stress relief and CH₄ release conditions based on fractal geometry theory. The permeability-enhancement rate was derived and verified through CT (Computed Tomography) characterization of the pore-fracture network. The fractal dimension of the fracture aperture distribution and the tortuosity of fracture paths were determined to establish a fractal permeability-enhancement model, and its sensitivity was analyzed. The results indicate that permeability evolution undergoes four distinct stages: a stable stage, a slow-growth stage, a rapid-growth stage, and a stable or declining stage. The mining-induced stress relief and gas desorption effects significantly accelerate permeability enhancement, providing new insights into the mechanisms governing gas flow and pressure relief in deep coal seams. The proposed model, highly sensitive to the fracture aperture ratio (λ_min/λ_max), reveals that a smaller aperture span leads to greater permeability enhancement during the damage and fracture stage. These findings offer practical guidance for predicting permeability evolution, optimizing gas drainage design, and enhancing the safety and efficiency of coal mining and methane extraction operations. Full article

This study aims to develop a non-contact automated impact-acoustic measurement system (AIAMS) for real-time detection of manufacturing defects in automotive brake calipers, a key component of the Electric Parking Brake (EPB) system. Calipers hold brake pads in contact with discs, and defects caused by repeated loads and friction can lead to reduced braking performance and abnormal vibration and noise. To address this issue, an automated impact hammer and a microphone-based measurement system were designed and implemented. Feature extraction was performed using Fast Fourier Transform (FFT) and Principal Component Analysis (PCA), followed by defect classification through machine learning algorithms including Support Vector Machine (SVM), k-Nearest Neighbor (KNN), and Decision Tree (DT). Experiments were conducted on five normal and six defective caliper specimens, each subjected to 200 repeated measurements, yielding a total of 2200 datasets. Twelve statistical and spectral features were extracted, and PCA revealed that Shannon Entropy (SE) was the most discriminative feature. Based on SE-centric feature combinations, the SVM, KNN, and DT models achieved classification accuracies of at least 99.2%/97.5%, 98.8%/98.0%, and 99.2%/96.5% for normal and defective specimens, respectively. Furthermore, GUI-based software (version 1.0.0) was implemented to enable real-time defect identification and visualization. Field tests also demonstrated an average defect classification accuracy of over 95%, demonstrating its applicability as a real-time quality control system. Full article

This study quantifies how pressurized water immersion alters the reciprocating sliding behavior of glass and Kevlar woven fabric-reinforced polymer hybrid composite laminates. Specimens were immersed in deionized water at 10 bar and 25 °C for 0, 7, 14, and 21 days, then tested against a 6 mm 100Cr6 steel ball at 20 N under four regimes that combine 1 or 2 Hz with 10 m or 20 m total sliding. Water uptake rose from 0 to 8.54% by day 21 and followed a short-time Fickian square root of time trend, indicating diffusion-controlled sorption. The coefficient of friction exhibited a robust nonmonotonic response with a pronounced minimum at 14 days that was typically 20 to 40% lower than the unaged reference across frequencies and distances, while 7 days produced a partial decrease and 21 days trended upward. Three-dimensional profilometry showed progressive widening and deepening of wear tracks with immersion, for example, at 1 Hz and 10 m width increased from about 1596 to about 2050 to 2101 μm and depth from about 128 to about 184 to 185 μm, with a transient narrowing at 2 Hz after 7 days. Scanning electron microscopy corroborated a transition from mild plowing to matrix plasticization with fiber–matrix debonding and debris compaction. Beyond geometric wear metrics, this study re-processed the existing profilometry and COF records to derive a moisture-dependent mechanistic approach. Moisture uptake up to 8.54% reorganizes the third body at the interface so that friction drops markedly at 14 days (typically 20–40% below the unaged state), while concurrent matrix plasticization and interface weakening enlarge the wear cross-section extracted from the same 3D maps, decoupling friction from damage width/depth under wet conditioning. Factorial analysis ranked immersion time as the dominant driver of damage for width and depth with frequency as a secondary factor and sliding distance as a minor factor, highlighting immersion-controlled tribological design windows for marine and humid service. Full article

Introduction: Prostate cancer (PC) accounts for around 10% of all cancers worldwide and is the fourth most common neoplasm. Localized PC has high cure rates when diagnosed early, but 35% of patients progress to the metastatic form. The search for new molecular markers, such as microRNAs, is fundamental to improving diagnosis and treatment. The role of miR-10a is controversial between tumor tissues, opening a niche for studies on their role in PC. Objectives: To evaluate the role of miR-10a in metastatic PC cell lines, focusing on the mechanisms of proliferation, migration, and invasion, and to analyze the expression in surgical specimens of localized PC. Methods: Three commercial metastatic PC cell lines were used: LNCaP, DU145 and PC-3. Expression of mimic miR-10a was induced by cell transfection, followed by extraction of miRNA and total RNA. The synthesis of complementary DNA (cDNA) and analysis by real-time PCR enabled the expression of miR-10a and the VEGF, MYC, and HAS3 genes to be assessed. Matrigel, colony formation, invasion, and migration assays were evaluated for the transfected cells. The surgical specimens were used to evaluate the miR-10a expression. Results: Transfected cells with mimic significantly increased the expression of miR-10a in the LNCaP (p = 0.0179), PC-3 (p ≤ 0.001), and DU145 (p ≤ 0.001) cell lines. Transfected cells reduced cell invasion in the PC-3 (p = 0.001) and DU-145 (p = 0.0004) cell lines and decreased cell migration and proliferation. In surgical specimens, miR-10a expression was higher in PC compared to Benign Prostatic Hyperplasia (p = 0.0010). Conclusions: Increased expression of miR-10a affects cell migration, invasion, and proliferation, showing potential as a therapeutic target in treating PC. Full article

This study presents a finite element analysis (FEA)-based numerical homogenization method for evaluating the effective thermo-mechanical properties of a large-area additively manufactured particulate-filled composite using realistic periodic representative volume elements (RVEs) generated from reconstructed X-ray µ-CT image scans of a 3D-printed bead. The numerical results of the predicted effective properties, including the elastic stiffness, coefficient of thermal expansion (CTE) and thermal conductivity, were benchmarked with the Mori–Tanaka–Benveniste analytical estimates, which were found to be comparable. Initial sensitivity analysis using a single region of interest (ROI) extracted from the bead’s volume was performed to determine a suitable RVE size. The impact of inherent micro-porosities on the resulting composite material’s behavior was also quantified in the current investigation and was shown to reduce the composite’s effective properties. Using a suitable RVE size, the effect of anisotropy due to spatial variation in the microstructure across the bead specimen on the computed composite’s effective properties was also assessed. The results show that the regions closer to the exposed surface of the print bead with highly aligned and densely packed fiber particulates have superior properties as compared to inner regions with a more randomly oriented and less densely packed fibrous microstructure. Full article

Background/Objectives: Acute respiratory infections remain a major global public health concern affecting individuals across all ages. Accurate and rapid diagnosis of respiratory pathogens is crucial for effective patient management and infection control. Multiplex real-time polymerase chain reaction (PCR) assays have gained prominence over conventional methods for routine viral detection in clinical laboratories owing to their enhanced sensitivity and specificity; however, comparative performance data for PowerChek™ RVP remain limited. This study aimed to evaluate the diagnostic performance of the PowerChek™ Respiratory Virus Panel 1/2/3/4, which detects 16 respiratory viruses, including SARS-CoV-2, in nasopharyngeal swab (NPS) specimens. Methods: Overall, 336 NPS specimens were analyzed using the PowerChek™ RVP, BioFire^® RP 2.1plus, and Allplex™ RP assays, with nucleic acid extraction performed using the Advansure™ E3 system. The performance metrics were calculated using two-by-two contingency tables. Results: Among 336 NPS specimens (232 positive, 104 negative), PowerChek™ RVP detected 226 positives with minimal discrepancies, showing high concordance with BioFire^® RP 2.1plus (accuracy 94.6%, kappa 0.843–1.000). Fifteen discordant cases were identified in this study. Eleven could not be sequenced because of amplification failure and most had high Ct values (>30). Sequencing of four samples confirmed concordance with BioFire^® RP 2.1plus and PowerChek™ RVP, whereas Allplex™ RP showed false-negative results. Conclusions: The PowerChek™ RVP assay demonstrated a high level of relative sensitivity, specificity, accuracy, diagnostic predictive values and strong concordance with comparable reference assays in identifying its targets. This assay is a reliable and efficient diagnostic tool for clinical laboratories to facilitate the accurate identification of respiratory pathogens. Full article

We propose a novel meta-learning enhanced 3D CNN-LSTM framework for durability prediction. The framework integrates 3D microstructural data from micro-CT scanning with environmental time-series data through a dual-branch architecture: a 3D CNN branch extracts spatial degradation patterns from volumetric data, while an LSTM network processes temporal environmental factors. To address data scarcity, we incorporate a prototypical network-based meta-learning module that learns class prototypes from limited support samples and generalizes predictions to new corrosion scenarios through distance-based probability estimation. Additionally, we develop a dynamic feature fusion mechanism that adaptively combines spatial, environmental, and mechanical features using trainable attention coefficients, enabling context-aware representation learning. Finally, an interface damage visualization component identifies critical degradation zones and propagation trajectories, providing interpretable engineering insights. Experimental validation on laboratory specimens demonstrates superior accuracy (74.6% in 1-shot scenarios) compared to conventional methods, particularly in aggressive corrosion environments where data scarcity typically hinders reliable prediction. The visualization system generates interpretable 3D damage maps with an average Intersection-over-Union of 0.78 compared to ground truth segmentations. This work establishes a unified computational framework bridging microstructure analysis with macroscopic durability assessment, offering practical value for infrastructure maintenance decision-making under uncertainty. The modular design facilitates extension to diverse interface types and environmental conditions. Full article

Identification of the strength characteristics of mortars in brick or stone masonry is crucial in the structural analysis of heritage buildings and selecting materials for their repairs and reconstruction. Non-destructive, minimally destructive, and minor-destructive tests have been developed to establish the strength of mortar in existing masonry. This paper presents strength tests on mortar samples extracted from bed joints of heritage buildings erected in the historic center of Cracow during the 19th and 20th centuries. The mortar samples were tested using the double-punch method, a minor-destructive technique especially useful for heritage structures where cutting out large masonry specimens is not possible due to conservation reasons. The impact of sample thickness and type of capping materials on the test results were analyzed in detail. Practical recommendations are also proposed for the procedure of the double-punch method in relation to historical mortars. Full article

This study investigates the mineralogical and physical properties of serpentinite from the Monteferrato area (Tuscany, Italy) to evaluate its potential use in Tuscany architectural restoration. The research addresses the need to identify replacement materials compatible with historic stones while preserving their original features. Representative specimens from the Bagnolo quarry were analysed through physical testing and a wide range of mineralogical and geochemical techniques, including polarised light microscopy, X-ray diffraction, electron probe micro-analysis, whole-rock chemistry, and fibre quantification. The results show a mineralogical composition dominated by serpentine-group minerals and magnetite, with physical properties generally consistent across samples. Measured capillary water absorption ranges from 3.27 to 5.27 g/m²·s^0.5, open porosity from 5.25% to 8.93%, apparent densities range from 2.49 to 2.56 g/cm³, and imbibition coefficient from 2.16% to 3.71%. Comparative analysis with serpentinite from historic sources (Figline di Prato quarry, Tuscany) and from monuments (Baptistery of San Giovanni, Florence) demonstrates close compositional and textural affinities, supporting the suitability of the rock from the studied quarry for restoration purposes in Tuscany monuments. However, chrysotile concentrations up to 14,153 mg/kg, exceeding Italian regulatory thresholds, represent a critical limitation. This not only requires the implementation of strict safety measures but also raises serious concerns regarding the practical feasibility of using this stone in conservation projects. More broadly, the presence of asbestiform minerals in serpentinites highlights a significant and often underestimated health risk associated with their extraction, processing, and use. Despite its importance, detailed fibre count data are rarely published or made publicly accessible, hindering both transparent risk assessment and informed decision-making. By integrating petrographic, mineralogical, and physical–mechanical characterisation with fibre quantification, this study not only assesses the technical suitability of Monteferrato serpentinites for restoration of Tuscan monuments but also contributes to a more responsible and evidence-based approach to their use, emphasising the urgent need for transparency and health protection in conservation practices. Full article

The fracture behavior of the Al₄Cu₉ intermetallic compound at the interface of impact-welded Cu/Al joints remains insufficiently explored through integrated multiscale modeling and experimental validation. In this study, molecular dynamic (MD) simulations, finite element (FE) analysis implemented in ABAQUS (version 2020) and a cohesive zone model (CZM) were combined with optical microscopy (OM) and scanning electron microscopy (SEM) observations of the interface and crack initiation zones in impact-welded Cu/Al specimens to investigate crack propagation mechanisms under different defect configurations. The experimental specimens consisted of 1060 aluminum (Al) and oxygen-free high-conductivity (OFHC) copper, fabricated via impact welding and subsequently annealed at 250 °C for 100 h. The interfacial morphology and crack initiation features obtained from OM and SEM provided direct validation for the traction–separation (T-S) parameters extracted from MD and mapped into the FE model. The results indicate that composite defects (blunt crack + void) cause a significantly greater reduction in fracture energy and stress intensity factor than single defects and that defect effects outweigh temperature effects within the range of 200–500 K. The experimentally observed crack initiation locations were in strong agreement with simulation predictions. This integrated simulation–experiment approach not only elucidates the multiscale fracture mechanisms of the Al₄Cu₉ interface but also provides a physically validated basis for the reliability assessment and optimization of aerospace Cu/Al welded structures. Full article

Introduction: Charred bodies represents a significant challenge for forensic pathologists due to the destructive effects of fire on human remains. Although most fire-related deaths are accidental, cases of suicide and homicide are not uncommon. Case Report: We report a peculiar case of a severely burned body discovered inside a torched vehicle. Under judicial investigation, a full autopsy was performed, including macroscopic and microscopic examination of key anatomical structures: the inspection of oral cavity revealed no soot deposits; a foreign object (a chestnut) was found anterior to the epiglottis, though not lodged within the glottis; no thermal injuries or soot were observed in the upper or lower airways. Histological analysis excluded thermal damage at the alveolar–capillary interface. Alveolar spaces appeared both hyperinflated and ectatic, likely due to septal rupture, suggestive of acute pulmonary emphysema and multiorgan congestion. Carboxyhemoglobin levels were below 5%, indicating a low level which did not support intravital inhalation of combustion gases. Based on the comprehensive medico-legal findings, the cause of death was attributed to an asphyxial mechanism. It was further demonstrated that the burning of the body occurred post-mortem. DNA extraction from two dental specimens enabled positive identification of the victim. Subsequent investigations confirmed the case to be a femicide. The perpetrator, following a domestic altercation over jealousy, suffocated his young wife and attempted to simulate accidental choking by placing a chestnut in her mouth. He then staged a vehicular fire to mimic a fatal accident. Conclusions: The case underlines that a multidisciplinary forensic approach is essential, and must integrate different methodologies and the analysis of both circumstantial evidence and scene investigation. Full article

Background: Trichomonas vaginalis is the causative agent of human trichomoniasis, the most common non-viral sexually transmitted infection. This disease is associated with an increased susceptibility to HIV and HPV infections. Currently, resistance to metronidazole (MTZ), the main drug used for treatment, has been reported in up to 9.6% of cases; additionally, the compound is also associated with adverse side effects. Therefore, it is urgent to identify new treatment options. Objective: In this study, we investigated for the first time the in vitro and in silico activity against T. vaginalis of betulin and stigmasterol isolated from Tagetes nelsonii Greenm, as well as their hemolytic activity. Methods: Plant specimen was collected in Chiapas, Mexico. Hexane and methanol extracts were prepared through sonication-assisted maceration. The antiprotozoal and hemolytic activities were evaluated in vitro against Trichomonas vaginalis trophozoites and human erythrocytes. The most active extract was fractionated using chromatographic techniques in a bioassay-guided study. The active metabolites were identified by ¹H and ¹³C-NMR spectroscopy, and their biological activity was further assessed in silico against lactate dehydrogenase (LDH), pyruvate ferredoxin oxidoreductase (PFOR) methionine gamma-lyase (MGL) and purine nucleoside phosphorylase (PNP) T. vaginalis enzymes. Results: Both triterpenes showed anti-trichomonal activity and no hemolytic activity at 100 µg/mL. Molecular docking studies predicted promising interactions of triterpenes with T. vaginalis drug target proteins, TvpFOR and TvLDH. Conclusions: Our results revealed that betulin and stigmasterol are potential molecules for the development of new trichomonacidal therapies against T. vaginalis. Full article

Background/Objectives: Screw loosening and vertebral fractures remain common after vertebral body tethering (VBT). Because tightening torque sets screw preload, its biomechanical effect warrants explicit modeling. In this paper, a Finite Element (FE) model, supported by ex vivo porcine vertebral tests, was developed and validated that incorporates torque-induced pre-tension to quantify vertebral stress, aiming toward customizable VBT planning. Methods: An FE model with pre-tension and axial extraction failure was parameterized using ex vivo tests on five porcine vertebrae. A laterally inserted surgical screw in each specimen was tightened to $5.9\pm 0.80$ Nm. Axial extraction produced failure loads of $2.1\pm 0.31$ kN. This is also considered in the FE model to validate the failure scenario. Results: Torque alone generated peak von Mises stresses of $16.1\pm 0.86$ MPa (cortical bone 1) and $2.1\pm 0.13$ MPa (trabecular), lower than prior reports. With added axial load, peaks rose to $141.1\pm 0.70$ MPa and $19.7\pm 0.23$ MPa, exceeding typical ranges. However, predicted failure agreed with experiments, showing $0.58$ mm displacement and a conical displacement distribution around the washer. Conclusions: Modeling torque-induced pre-tension is essential to reproduce realistic stress states and anchor failure in VBT. The framework enables patient-specific assessment (bone geometry/density) to recommend safe tightening torques, potentially reducing screw loosening and early fractures. Full article

Objective: This retrospective study investigated the relationship between the timing of single-tooth implant-supported restorations—including the interval from tooth extraction and socket preservation to implant placement and final prosthetic restoration—and the severity of periapical inflammation, as classified by the Dental Apical Inflammation Score (DAIS). Methods: A total of 87 patients were included (DAIS 1: 8; DAIS 2: 14; DAIS 3: 1; DAIS 4: 64). Procedural intervals (extraction, socket preservation, implant placement, and prosthetic restoration) were analyzed alongside histological assessment of periapical inflammation. Clinical parameters such as tooth location, endodontic treatment status, patient age, and sex were examined using ANOVA, chi-square tests, and Pearson’s correlation analysis. Results: An effective sample size of N = 86 (excluding the single DAIS 3 case) was included in the parametric analysis. No significant differences in procedural timing were found across DAIS groups for the intervals between extraction and implant placement (F(2, 83) = 0.338, p = 0.714) or restoration (F(2, 83) = 1.016, p = 0.367). Tukey’s HSD post hoc analysis showed no pairwise group differences. Histological diagnosis was not significantly associated with DAIS (χ²(6) = 7.00, p = 0.321), though small subgroup sizes warrant interpretive caution. A significant association was identified between DAIS score and tooth location (χ²(3) = 11.79, p = 0.008). Patient age showed a weak but significant positive correlation with DAIS (r = 0.222, p = 0.039). No significant associations were found for endodontic status (χ²(3) = 2.54, p = 0.468) or sex (χ²(3) = 2.63, p = 0.452). Histological assessment revealed that most specimens represented radicular cysts with varying proportions of acute and chronic inflammatory infiltrates, consistent with the DAIS classification. Conclusions: Procedural timing did not significantly differ between DAIS groups. However, the observed associations with tooth location and patient age may warrant further investigation into their potential relevance for treatment planning. These findings suggest that implant timing may not need to be substantially modified according to DAIS severity alone, but that anatomical site and patient age should be considered during clinical decision-making. Full article