Search Results (1,964)

This study develops a ship propeller diagnostic system to address the issue of insufficient ship maintenance capacity and enhance operational efficiency. It uses the Remaining Useful Life (RUL) prediction technology to establish a sensing platform for ship propellers to capture vibration signals during ship operations. The Diagnosis and RUL Prediction Model is designed to assess bearing aging status and the RUL of the propeller. The synchronized signal reshaping technology is employed in the Diagnosis and RUL Prediction Model to process the original vibration signals as input to the model. The vibration signals obtained are used to analyze the temporal and spectral energy of propeller bearings. Exponential functions are used to generate the health index as model outputs. Model inputs and outputs are simultaneously input into a Long Short-Term Memory (LSTM) model for training, culminating as the Diagnosis and RUL Prediction Model. Compared to Recurrent Neural Network and Support Vector Regression models used in previous studies, the Diagnosis and RUL Prediction Model developed in this study achieves a Mean Squared Error (MSE) of 0.018 and a Mean Absolute Error (MAE) of 0.039, demonstrating outstanding performance in prediction results and computational efficiency. This study integrates the Diagnosis and RUL Prediction Model, bearing aging experimental data, and real-world vibration measurements to develop the diagnosis and RUL prediction system for ship propellers. Experiments with ship propellers show that when the bearing of the propeller enters the worn stage, this diagnostic system for ship propellers can accurately determine the current status of the bearing and its remaining useful life. This study offers a practical solution to insufficient ship maintenance capacity and contributes to improving the operational efficiency of ships. Full article

In modern industry, the spring full-lift safety valve is a key device for safe pressure relief of pressure-bearing systems. Its valve seat sealing surface is easily damaged after long-term use, causing internal leakage, resulting in safety hazards and economic losses. Therefore, it is of great significance to quickly and accurately diagnose its internal leakage state. Among the current methods for identifying fluid machinery faults, model-based methods have difficulties in parameter determination. Although the data-driven convolutional neural network (CNN) has great potential in the field of fault diagnosis, it has problems such as hyperparameter selection relying on experience, insufficient capture of time series and multi-scale features, and lack of research on valve internal leakage type identification. To this end, this study proposes a safety valve internal leakage identification method based on high-frequency FPGA data acquisition and improved CNN. The acoustic emission signals of different internal leakage states are obtained through the high-frequency FPGA acquisition system, and the two-dimensional time–frequency diagram is obtained by short-time Fourier transform and input into the improved model. The model uses the leaky rectified linear unit (LReLU) activation function to enhance nonlinear expression, introduces random pooling to prevent overfitting, optimizes hyperparameters with the help of horned lizard optimization algorithm (HLOA), and integrates the bidirectional gated recurrent unit (BiGRU) and selective kernel attention module (SKAM) to enhance temporal feature extraction and multi-scale feature capture. Experiments show that the average recognition accuracy of the model for the internal leakage state of the safety valve is 99.7%, which is better than the comparison model such as ResNet-18. This method provides an effective solution for the diagnosis of internal leakage of safety valves, and the signal conversion method can be extended to the fault diagnosis of other mechanical equipment. In the future, we will explore the fusion of lightweight networks and multi-source data to improve real-time and robustness. Full article

Background: Osteosarcoma (OS) is the most commonly occurring type of bone cancer in both humans and canines. The survival outcomes for OS patients have not improved significantly in decades. A novel and innovative treatment option that is currently under investigation for OS in the veterinary field is the focused ultrasound ablation modality, histotripsy. Histotripsy is a non-thermal, non-invasive, non-ionizing ablation modality that destroys tissue through generation of acoustic cavitation. Objective: In the current study, we sought to investigate the utility of an orthotropic OS xenograft murine model for characterization of chronic ablative and clinical outcomes post-histotripsy ablation. Method: Given the high comparative relevance of canine to human OS, histotripsy was delivered to orthotopic OS tumors in both human and canine xenograft murine models. Results: Histotripsy improved limb function in tumor-bearing mice compared to untreated tumor bearing mice. The results of this study demonstrated the utility of the orthotopic OS xenograft murine model for histotripsy-based preclinical studies. Conclusions: The current study is the first published investigation for the use of an orthotopic xenograft murine model for the development of histotripsy ablation for OS. The developmental process of the model, technical limitations, and future directions are discussed. Full article

Hepatocellular carcinoma (HCC) is a leading cause of global cancer-related mortality worldwide. Increasing evidence indicates that epigenetic mechanisms, which are potentially reversible and modifiable by environmental and nutritional factors, play a key role in hepatocarcinogenesis. Histone deacetylases (HDACs) are fundamental epigenetic modulators that regulate chromatin dynamics and ultimately gene transcription with important pathophysiological implications and promising therapeutic perspectives. The role of HDACs is gaining interest for the understanding of HCC development mechanisms and for the potential therapeutic implications of their natural and synthetic inhibitors. This review provides an overview on HDACs classification and their peculiar expression patterns in HCC, with a focus on zinc-dependent histone deacetylases (HDACs). HDAC inhibitors (HDACis), both synthetic and natural-derived compounds, are also discussed for their emerging effects in optimizing the anticancer efficacy of the current therapeutic strategies. Novel dietary-derived and bioactive compounds-based interventions are discussed in the context of HCC management as promising nutri-epigenetic avenues. Targeting HDACs bears a significant therapeutic potential for HCC management while further confirmatory clinical investigation is warranted. Full article

The rapid development of transportation infrastructure in mountainous terrains, soft-soil foundations, and high-fill embankments poses stability challenges for conventional embankments, driving the application of advanced three-dimensional reinforced soil technologies. Geogrid with Strengthened Nodes (GSN) is one such innovation, forming a three-dimensional structure by placing block-shaped nodes at geogrid rib intersections. Current research on GSN focuses mainly on pullout tests and numerical simulations, while model-scale studies of its load-bearing deformation behavior and soil pressure distribution remain scarce. This study presents laboratory model tests to assess the reinforcement performance of GSN-reinforced embankments under static and dynamic strip loads. Under static loading, the ultimate bearing capacity of GSN-reinforced embankments increased by 74.58% compared with unreinforced cases and by 26.2% compared with conventional geogrids. Under dynamic loading, cumulative settlement decreased by 32.82%, and lateral displacement at the slope crest was reduced by 64.34%. The strengthened node design improved soil shear strength and controlled lateral deformation via enhanced lateral resistance, creating a more stable “reinforced zone” that alleviated local stress concentrations. Overall, GSN significantly enhanced embankment bearing capacity and stability, outperforming traditional geogrid reinforcement under both static and dynamic conditions, and providing a promising solution for challenging geotechnical environments. Full article

In view of the adverse effect of the failure mode of the “strong beam and weak column” at the top-layer joint of subway stations on structural seismic performance under high axial compression ratio, a novel assembled steel–concrete composite (ASCC) beam–column joint for the top-layer is proposed in this paper, and its seismic performance is studied through cyclic loading tests and finite element analysis. The findings indicate that, in comparison to the reinforced concrete joint, the yield bearing capacity, ultimate bearing capacity, and ductility of the ASCC joint exhibit increases of approximately 46%, 13% and 40%, respectively, demonstrating superior seismic performance and a “strong column and weak beam” failure mode of the ASCC joint. The impact of parameters including the steel tube thickness, length of the lower steel tube, high axial compression ratio, and bolt quantity on the seismic performance of ASCC joints was further examined using a validated finite element model. Parametric investigations reveal that the ASCC joints with greater steel tube thickness, longer length of lower steel tube, and more bolts demonstrate significant improvements in load-bearing capacity, lateral displacement resistance, and energy dissipation capacity. A value of 0.80 can be recommended as the new high axial compression ratio upper limit of the current code. It is suggested that under the proposed new high axial compression ratio upper limit, the steel tube thickness should be 1–2% of the column diameter, while the length of the lower steel tube should be 1/3 of the length of the lower column, with more bolts restricting the deformation of the extended plates as the design and construction of joints better suit practical engineering applications. Full article

The Huangliu Formation, Section I, Gas Group II, at the eastern X gas field of the Yinggehai Basin, hosts thick, irregularly deposited sandstone bodies. The genesis of these sedimentary sand bodies has remained unclear. Utilizing drilling logs, core samples, and 3D seismic data from this field, this study integrates seismic geomorphology analysis, paleo-hydrodynamic reconstruction, and sedimentary numerical simulation to investigate the spatiotemporal evolution of the depositional system under micro-paleotopographic conditions during Gas Zone II sedimentation. Key conclusions include the development of seven morphologically diverse isolated sand bodies in the Lower II Gas Zone, covering areas of 1.4–13.4 km² with thicknesses ranging from 8.0 to 42.0 m. These sand bodies consist predominantly of massive fine-grained sandstone, characterized by box-shaped gamma-ray (GR) log responses and U- or V-shaped seismic reflection configurations. Reconstruction of paleo-turbidity current hydrodynamics for the Lower II depositional period was achieved through analysis of topographic slope gradients and the dimensional constraints (width/depth) of confined channels. Critically, slope gradients within the intraslope basin prompted a transition from supercritical to subcritical flow states within turbidity currents. This hydraulic transformation drove alternating erosion and deposition along the seafloor topography, ultimately generating the observed irregular, isolated turbidite sand bodies. Full article

Traditional support methods, such as full-frame scaffolding, often pose significant safety risks during the replacement of defective concrete. In contrast, the application of programmable logic controller (PLC) synchronous jacking technology combined with an encircling beam is an innovative approach to concrete replacement. However, there is currently a lack of effective theoretical guidance for determining its design parameters, and there are also few measured data available to verify its effectiveness. To address this issue, this study investigates a concrete structure in which it was discovered, during the topping-out phase, that the compressive strength of several load-bearing columns did not meet the design specifications. Through structural analysis and load calculations, a reinforcement scheme utilizing the synchronous jacking system in conjunction with an encircling beam was proposed to replace the defective concrete. The monitoring of the settlement and deformation during the replacement process revealed a minimal settlement of 0.45 mm, which is approximately 23% of the predefined warning threshold. The results demonstrate that the integration of the synchronous jacking system with an encircling beam offers a safe and reliable solution, thus providing an effective approach to addressing similar challenges in concrete structural reinforcement. Full article

The present study offers a systematic review of the current state of research on lattice structures manufactured by additive technologies for biomedical applications, with the aim of identifying common patterns, such as the use of triply periodic minimal surfaces (TPMS) for bone scaffolds, as well as technological gaps and future research opportunities. Employing the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology, the review process ensures methodological rigor and replicability across the identification, screening, eligibility, and inclusion phases. Additionally, PRISMA was tailored by prioritizing technical databases and engineering-specific inclusion criteria, thereby aligning the methodology with the scope of this field. In recent years, a substantial surge in interdisciplinary research has underscored the promise of architected porous structures in enhancing mechanical compatibility, fostering osseointegration, and facilitating personalized medicine. A growing body of literature has emerged that explores the optimization of geometric features to replicate the behavior of biological tissues, particularly bone. Additive manufacturing (AM) has played a pivotal role in enabling the fabrication of complex geometries that are otherwise unachievable by conventional methods. The applications of lattice structures range from permanent load-bearing implants, commonly manufactured through selective laser melting (SLM), to temporary scaffolds for tissue regeneration, often produced with extrusion-based processes such as fused filament fabrication (FFF) or direct ink writing (DIW). Notwithstanding these advances, challenges persist in areas such as long-term in vivo validation, standardization of mechanical and biological testing, such as ISO standards for fatigue testing, and integration into clinical workflows. Full article

The negative Poisson’s ratio structure has special deformation behavior and energy absorption characteristics and is a new structure with broad application prospects. However, most of the current research is still at the theoretical level, while research on its practical performance is sparse. Therefore, this paper proposes an elliptical negative Poisson’s ratio structural isolation bearing (NRB) for application in the field of seismic isolation engineering. The finite element simulation method is used to conduct a mechanical comparison with the traditional high damping isolation bearing (HDR), highlighting the advantages of the NRB in isolation and energy absorption. At the same time, parameter analysis is used to study the influence of the number and angle of structural holes on the stress of the NRB structure, which is 80% higher than that of the traditional isolation bearing, and incremental dynamic analysis (IDA) is also used. The overall average damage rate decreased by 70.3%, showing significant advantages in seismic energy dissipation, control of component damage, and other aspects, providing a strong data basis for the application of seismic isolation technology in practical engineering. Full article

In the digital environment, grooming—classified as a communication-based risk—has shown a steadily increasing frequency in recent years. In Hungary, increasing attention has been directed to the protection of children’s rights in the digital space in alignment with ensuring their online safety, with both parents and the state playing crucial roles in ensuring a safe digital presence. Within this context, the state bears a particular responsibility to educate not only children but also parents. This study explores how public policies and institutional programs in Hungary address the prevention of grooming and the reactive management of this harm through parental awareness. It examines existing measures aimed at expanding knowledge related to prevention and response, based on a qualitative analysis of the normative foundations of the state’s educational obligations and the relevant academic literature. The study relies on questionnaire data collected from parents of children aged 7 to 18 to examine the effectiveness of state measures and parents’ perceptions of them. The findings of the empirical research may support the development of state-led parental education programs and identify current gaps. As such, it can play a guiding role in shaping the direction of a future, large-scale investigation. Full article

Background: Mandibular defects caused by trauma or tumor resection pose significant challenges in both functional and aesthetic reconstruction. Additive manufacturing (AM) technologies offer promising solutions for surgical planning and personalized treatment. Objectives: This review aims to evaluate current trends in the application of AM technologies for mandibular resection and reconstruction, with a particular focus on material selection, clinical integration, and technology-specific advantages. Methods: A structured literature review was performed using PubMed, Scopus, Web of Science, and Google Scholar. Studies published between January 2020 and May 2025 were screened using the following inclusion criteria: original peer-reviewed English-language research involving AM in mandibular surgery. The exclusion criteria included review articles, non-English sources, and non-mandibular studies. A total of 77 studies met the inclusion criteria and were analyzed in this review. Results: Based on the literature review conducted from 2020 to 2025, the most common restorative methods for the mandible using additively manufactured models include reconstruction with a titanium surgical plate bent to the curvature of the edges and angle of the mandible or a personalized titanium or PEEK surgical plate made directly based on the patient’s diagnosis. Implants made of Ti-6AL-4V ELI and bioceramic scaffolds are also used in the reconstruction process. They are developed based on patient diagnostic data and effectively replace the loss of mandibular bone structure. In addition, based on models and surgical guides created using additive manufacturing techniques, the performance of autogenous grafts from the fibula or iliac crest has improved significantly when used with a titanium implant plate. Conclusions: Additive manufacturing supports highly personalized and accurate mandibular reconstruction. The advantages of these methods include a reduced overall duration of procedures, a lower health risk for patients due to less reliance on general anesthesia, a near perfect match between the implant and the remaining hard tissues, and satisfactory aesthetic outcomes. However, success depends on the appropriate selection AM technology and material, particularly in load-bearing applications. Full article

Background: Despite significant advancements in HIV prevention, Africa continues to bear a disproportionately high burden of new infections. Pre-exposure prophylaxis (PrEP) has demonstrated over 90% efficacy in preventing HIV acquisition when taken consistently; however, its implementation and uptake across African countries remain suboptimal. Objective: This scoping review aims to systematically map existing literature on PrEP uptake and implementation in Africa, identify key barriers and facilitators influencing access and adherence, examine targeted population groups, and explore policy and programmatic approaches to PrEP delivery across diverse African contexts. Methods: The review will follow the methodological framework proposed by Arksey and O’Malley, refined by Levac et al., and will include comprehensive searches of electronic databases, grey literature, and official reports. Data will be thematically synthesized to identify research trends, gaps, and contextual variations. Expected Outcomes: The findings will provide a comprehensive overview of the current landscape of PrEP implementation in Africa, highlighting research trends, contextual variations across countries, and gaps in service delivery and policy frameworks. This will inform future implementation strategies, guide evidence-based approaches to enhance PrEP uptake, and support policymaking to scale up effective interventions across diverse African settings, ultimately contributing to HIV prevention efforts on the continent. Full article

Hemophilias and hemoglobinopathies—including hemophilias A and B, sickle cell disease (SCD), and β-thalassemia—are debilitating genetic disorders associated with significant global health burdens. While traditional management has centered on factor replacement and transfusions, these approaches remain palliative, with limited access and durability in many regions. Recent advances in immune-based therapeutics (e.g., emicizumab, concizumab, crizanlizumab), viral vector-mediated gene addition (e.g., Roctavian, Hemgenix), and gene-modified autologous stem cell therapies (e.g., Zynteglo, Casgevy) have ushered in a new era of disease-modifying and potentially curative interventions. These therapies offer durable efficacy and improved quality of life, particularly in adult populations. However, implementation remains uneven across global health systems due to high costs, limited infrastructure, and regulatory heterogeneity. Additionally, ethical considerations such as long-term surveillance, informed consent in vulnerable populations, and social perceptions of genetic modification present ongoing challenges. Innovations such as multiplex genome editing, immune-evasive donor platforms, synthetic biology, and AI-driven treatment modeling are poised to expand therapeutic horizons. Equitable access, particularly in regions bearing the highest disease burden, will require collaborative funding strategies, regional capacity building, and inclusive regulatory frameworks. This review summarizes the current landscape of curative therapy, outlines implementation barriers, and calls for coordinated international action to ensure that transformative care reaches all affected individuals worldwide. Full article

The axle-box bearing is a critical load-bearing component in high-speed trains and is prone to failure under long-term heavy-duty operation, affecting both operational efficiency and safety. Current deep-learning-based fault diagnosis methods face two key challenges: difficulty in capturing temporal features across multiple scales simultaneously, and limited capability in modeling local sequential patterns. To address these issues, we propose P2IFormer, a fault diagnosis model based on multi-granularity patch-to-image embedding. The raw vibration sequence is divided into equal-length patch sequences under multiple granularities, each defined by a fixed window size. Each patch is then transformed into a Gramian Angular Field (GAF) image to extract spatial features and generate granularity-specific embedding. A multi-granularity self-attention mechanism is used to model both intra- and inter-granularity dependencies. The resulting multi-granularity features are fused and fed into a softmax classifier for final fault prediction. Experiments conducted under four constant-speed conditions and one variable-speed condition demonstrate that P2IFormer achieves over 99.5% accuracy across all scenarios, significantly outperforming existing CNN- and Transformer-based methods. Full article