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Approximate solutions of the lane-emden equations by ls-svm method
No full textIn this study, approximate solutions of the Lane-Emden differential equation, which plays an important role in the literature, were obtained using the Least Squares Support Vector Machines (LS-SVM) method for both linear and nonlinear cases. The Collocation method was employed to define the constraints in the solution process. The system of equations obtained in the linear case was solved directly to determine the unknown parameters, while the Newton-Raphson method was used to solve the nonlinear equation system. The approximate solutions obtained in the applications considered in this study were compared with the exact solution for the linear case; with the analytical solution for the nonlinear case; and with the Adomian Decomposition Method (ADM) in the final application where no analytical solution exists. The results show that the numerical solutions obtained using the LS-SVM method are highly accurate and consistent with the reference results
Driving circular economy transitions through technological innovation in the top five waste-generating economies
No full textThe rapid increase in global consumption has led to substantial growth in waste generation, posing a significant challenge to achieving the Sustainable Development Goals (SDGs), particularly SDGs 11 and 12, which emphasize waste reduction. Technological progress in waste management and the ability to adapt these innovations to environmental needs play a crucial role in mitigating waste‑related pressures. This study investigates how economic growth, urbanization, environmental policy stringency (EPS), and innovations in waste management, recycling and reuse, and wastewater treatment affect the load capacity factor (LCF) in the top five waste-generating economies (U.S., Japan, Germany, France, and Türkiye) from 2005 to 2020. Using the Augmented Mean Group (AMG) and Half‑Panel Jackknife (HPJ) estimation approaches, the analysis reveals that economic growth and urbanization reduce LCF, indicating increased environmental degradation. In contrast, patents related to waste management, recycling, and wastewater treatment technologies improve LCF, supporting progress toward SDGs 11 and 12. EPS, however, shows no significant effect, highlighting inconsistencies in policy enforcement across these economies. Overall, the findings underscore the need for stronger regulatory frameworks that tighten environmental policies and incentivize technological innovation to advance circular economy transitions
Aerodynamic and control response of sandwich smart plates in aircraft wings subjected to lightning-induced hybrid electric shock: Advanced modeling and mitigation techniques
No full textThis research, for the first time and as a novel study, presents the aerodynamic and control response of sandwich smart plates embedded in aircraft wings under a combined electrical shock of both direct current (DC) and alternating current (AC) voltage surge, which is similar to a lightning strike. Unlike prior studies focusing solely on DC or AC components, this work establishes a coupled analytical framework for hybrid electrical shock, better representing real lightning physics. The proposed sandwich configuration comprises sensor and actuator face sheets and a hybrid nanocomposite reinforced core to provide multifunctional durability. Halpin–Tsai micromechanical model to estimate effective material properties for the core component. Structural modeling is performed using Carrera unified formulation (CUF) with equivalent single-layer (ESL) models expressed through Taylor series expansion. Refined finite element approximation uses Legendre polynomials and Lagrange-type shape functions, with the geometric relations developed through the mixed interpolation of tensorial components (MITC) method. The use of a single-layer substrate lossless structure and a three-layered lossless electromechanical active sensing and actuating configuration is examined. By embedding the constitutive and geometric relations into a unified modeling framework for the governing equations, the corresponding governing equations requiring consideration of coupled electromechanical–aerodynamic responses were developed. Control strategies are evaluated to mitigate destabilizing effects on the electromechanical boundary value problem caused by hybrid electric shocks, and the time delay feedback (TDF) with derivative action (DA) controller consistently enabled the best reduction in the response's vibration and stabilization. Overall, results can be used for the modeling and mitigation of lightning-induced hybrid electric shocks to aerospace structures while also providing valuable decision support information for the implementation of advanced smart wing technologies in the future
Test characteristics of emergency physician-performed point-of-care ultrasound for the diagnosis of intrauterine pregnancy: a systematic review and meta-analysis
No full textPoint-of-care ultrasound (PoCUS) has emerged as a critical tool for diagnosing intrauterine pregnancy (IUP) in symptomatic first-trimester patients, particularly in emergency settings. This meta-analysis aims to evaluate the test characteristics of PoCUS in diagnosing IUP. As a secondary objective, this study will also examine the accuracy of PoCUS in detecting fetal cardiac activity (FCA). This systematic review and meta-analysis was conducted following the PRISMA-DTA guidelines with the protocol registered in PROSPERO (ID: CRD42024596206). We performed a comprehensive search of PubMed, Scopus, Web of Science, Cochrane Library and Google Scholar up to November 2024, identifying studies that compared PoCUS to reference standards for IUP diagnosis. Seven studies (n = 1716) were included in the meta-analysis. Two independent reviewers performed study selection, data extraction, and quality assessment using the QUADAS-2 tool. A bivariate random-effects model was used to pool the diagnostic accuracy metrics. In this meta-analysis, PoCUS demonstrated a pooled sensitivity of 86.3% (95% CI: 75.6%–92.8%, I2 = 89.8%) and a specificity of 98.2% (95% CI: 86.6%–99.8%, I2 = 72.6%) for the identification of IUP. Sensitivity analysis showed a significant decrease in heterogeneity for specificity (from 72.6% to 0%), along with a slight increase in sensitivity (88.5%). The pooled positive likelihood ratio was 39.01 (95% CI: 16.00–95.1), and the negative likelihood ratio was 0.10 (95% CI: 0.05–0.21). Moreover, subgroup analysis revealed higher sensitivity (92%) in studies using transvaginal ultrasound as the reference standard. In addition, PoCUS demonstrated high specificity (100%) and variable sensitivity (81–96%) for identifying FCA across three studies, but the limited number of studies prevented further meta-analysis. PoCUS is highly effective for diagnosing IUP in symptomatic first-trimester patients, allowing for the ruling out of ectopic pregnancy. However, when PoCUS is negative or indeterminate, follow-up strategies such as serial β-hCG, repeat ultrasound, or clinical reassessment remain essential to ensure diagnostic safety
Intersection of precision nutrition and bladder cancer: a narrative state-of-the-art review of potential applications and challenges
No full textBladder cancer (BC) is a biologically heterogeneous tumor affected by genetic, metabolic, environmental, and lifestyle factors. Recent research indicates that nutrition can change the way urothelial cancer forms by affecting inflammation, oxidative stress, cellular energy, and the epigenome. It can also change the risk of BC and how well treatment works. Simultaneous progress in precision nutrition (PN) and nutriomic profiling—encompassing nutrigenomics, nutrigenetics, nutriepigenetics, metabolomics, and microbiome science—presents novel options to tailor dietary regimens beyond universal guidelines. In this review, we consolidate existing knowledge regarding the nutritional factors influencing BC, outline pertinent principles of PN for BC prevention and survival, and explore how urine proteomics and molecular subtyping facilitate the integration of PN into precision oncology. Our review examines the methodological, bioinformatic, biomarker, and clinical translation challenges that impede the implementation of PN in BC management; these challenges include the need for validated nutritional biomarkers with mechanistic endpoints, interoperable data platforms, and rigorously designed clinical trials. Finally, we emphasize future prospects for PN-guided medical nutrition therapy and dietary models during and after systemic treatment recovery. We propose research priorities that will facilitate the integration of PN-informed individualized dietary plans with medical and surgical approaches in BC treatment, aiming to decrease the costs associated with expensive or excessively aggressive treatment methods, thereby supporting long-term survival care. This review seeks to establish a conceptual framework for the integration of PN into BC management by delineating the opportunities and challenges, hence promoting hypothesis-driven research in a promising yet underexplored domain
Integrative osmotic–antioxidant mechanisms in salinity-stressed Gerbera jamesonii treated with proline–IAA and PGPR
No full textSalinity stress is a major abiotic constraint that adversely affects the productivity and ornamental value of Gerbera jamesonii Bolus ex Hook. f. This study evaluated the physiological and biochemical responses of two cultivars (‘Zingana’ and ‘Sene Vidi’) to NaCl-induced salinity and examined the mitigation potential of microbial and biostimulant applications. Plants were subjected to six treatments under controlled greenhouse conditions: Control, NaCl, NaCl + Bacteria, NaCl + Proline–IAA, Bacteria, and Proline–IAA. Salinity markedly reduced relative water content (RWC), chlorophyll pigments, and leaf area, while increasing lipid peroxidation (MDA), indicating oxidative and osmotic stress. The bacterial and Proline–IAA treatments, applied either alone or under salinity, alleviated these negative effects by maintaining water status, stabilizing pigments, and lowering MDA levels. The Proline–IAA biostimulant, in particular, enhanced osmotic regulation and chlorophyll preservation, while bacterial inoculation improved overall physiological resilience. Principal component and correlation analyses revealed strong positive associations among RWC, chlorophyll content, and leaf area, whereas MDA was negatively correlated with growth parameters. Overall, both microbial and Proline–IAA applications improved the salinity tolerance of G. jamesonii, supporting their use as sustainable tools for maintaining growth performance and ornamental quality under saline conditions
Advances in battery technologies for next-generation energy storage systems
No full textAdvancements in energy storage systems (ESS) are important to attaining a sustainable and resilient energy future. Despite significant advancements in battery technologies, including lithium-ion, sodium-ion, and redox flow batteries, numerous problems remain. These include low energy density, thermal instability, resource scarcity, high lifecycle costs, and ineffective recycling methods. Furthermore, the complexity of connecting battery systems to the grid while maintaining operational safety creates further impediments to implementation. Recent advancements, such as hybrid energy storage systems (HESS), better battery chemistries, and intelligent modeling tools based on MATLAB/Simulink R2025b, have shown promise in terms of performance, cost reduction, and more effective energy management. However, the scalability, recyclability, and real-world applicability of these systems require further exploration. The goal here is to provide a comprehensive overview of current and emerging battery technologies, focusing on technical performance, environmental sustainability, lifecycle cost modeling, and grid compatibility. This comprises a techno-economic study that employs process-based cost modeling (PBCM) and leveled cost of storage (LCOS), a thorough examination of green battery chemistries, and system-level modeling of battery and hybrid configurations. The study seeks to provide academics and stakeholders with a comprehensive framework that considers both the innovations and limitations of current ESS technologies in the context of global decarbonization targets
Experimental investigation and numerical validation of drilling machinability in FDM-printed PLA parts
No full textFused Deposition Modeling (FDM) is a widely used additive manufacturing technique that fabricates components through layer-by-layer deposition of thermoplastic materials. Due to its biodegradability, dimensional stability, and favorable flow behavior, polylactic acid (PLA) has become one of the most commonly employed polymers in extrusion-based printing. This study investigates the influence of extrusion temperature, infill pattern, and infill density on the mechanical performance and drilling machinability of FDM-printed PLA components. Tensile tests and hardness measurements were conducted to evaluate mechanical behavior, while drilling machinability was assessed through thrust force measurements and digital microscopy. In parallel, a three-dimensional finite element model was developed using ABAQUS/Explicit to capture damage initiation and interfacial degradation, providing numerical validation of the experimental results. The findings demonstrate that infill density is the dominant parameter, with higher densities leading to significant improvements in tensile strength, elastic modulus, and surface hardness. The grid infill at full density and elevated extrusion temperature yielded the highest mechanical performance, achieving a tensile strength of 40.3 MPa and a modulus of 3050 MPa. In contrast, the hexagonal infill pattern offered a favorable balance between mechanical strength and drilling performance, exhibiting reduced thrust force and improved damage resistance. Optimal drilling conditions were identified at 3000 rpm and 150 mm/min, minimizing delamination, burr formation, and thermal damage. Overall, this work highlights the strong coupling between process parameters, internal architecture, and numerical modeling in governing the structural integrity and machinability of FDM-fabricated PLA parts
Experimental comparison of heat transfer from a rectangular fin array and a circular tube bundle under free and forced convection
No full textThis study presents an experimental investigation of heat transfer enhancement from different surface configurations under natural and forced convection in a rectangular air duct, with relevance to thermal control approaches in building, landscape and environmental engineering applications. Experiments were conducted using a TecQuipment TD1005 unit to compare the thermal performance of a flat plate, a rectangular fin array, and a cylindrical tube bundle under identical heating and airflow conditions. Surface and base temperatures were measured to determine heat transfer coefficients and Nusselt numbers over a range of airflow velocities and applied heat fluxes. The novelty of this work lies in the direct experimental comparison of finned surfaces with different geometries in a ducted configuration, focusing on the combined effects of surface area modification and airflow under both natural and forced convection. The influence of surface geometry on temperature distribution along the fins was also examined. The results show that finned surfaces significantly outperform the flat plate. Under natural convection, finned configurations enhance heat transfer by approximately 200%, while under forced convection this improvement reaches up to 900%. Results indicate that cylindrical fins provide about 5% higher heat transfer performance than rectangular fins under similar conditions. However, rectangular fins exhibit more uniform temperature distributions and advantages in fabrication and integration. Increasing airflow velocity under forced convection reduces temperature gradients and improves cooling effectiveness. These findings provide quantitative insight into the effects of surface geometry and airflow on convective heat transfer and support the optimization of finned surfaces in thermal management applications
A multimodular ai algorithm for automated assessment of left ventricular function in ischemic heart disease: ejection fraction, wall motion, and regional myocardial segmentation
No full textBackground: Ischemic heart damage reduces the pumping efficiency of the heart by affecting the left ventricular ejection fraction (LVEF) and causing wall motion abnormality (WMA). In daily clinical practice, these parameters are interpreted by physicians using two dimensional transthoracic echocardiography (2D-TTE). Because 2D-TTE reports rely on visual evaluations, they are subject to experience-based limitations and exhibit low reproducibility. Aims: To develop an artificial intelligence algorithm composed of two modules that enable automatic LVEF calculation and WMA detection for analyzing 2D-TTE images. Study Design: Diagnostic accuracy study. Methods: A total of 600 adult patients were retrospectively included. The model combined static frame segmentation with dynamic tracking using a hybrid Simpson’s method applied to apical 2- and 4-chamber views. Model performance was assessed against cardiologist measurements using Bland-Altman analysis. The YOLOv8 and ResNet50 models were employed for the wall motion module. Performance metrics, including accuracy, precision, F1 score, and area under the curve, were evaluated. Results: In the Bland-Altman analysis, the mean bias between the LVEF module and cardiologist measurements was -4, with limits of agreement ranging from -15 to -3. Regression analysis demonstrated a strong correlation between the LVEF module and cardiologist measurements (r = 0.71, p < 0.001). In the wall motion module, the YOLOv8 segmentation model exhibited high accuracy, while ResNet50 achieved superior performance with an accuracy of 95%. The algorithm’s color coding contributed to standardized interpretation among operators, enhancing consistency. Conclusion: This is the first study to integrate automated EF calculation and WMA detection within a single workflow. SafeHeart offers accurate, reproducible, and rapid analysis, with the potential to support routine echocardiography practice. Color-coded region segmentation can facilitate more standardized and reliable results