Search Results (12,579)

Background/Objectives: The objective assessment of natural tooth mobility remains challenging in clinical practice. This pilot study aimed to investigate the feasibility, repeatability, and agreement of a modified implant stability measurement system adapted for natural teeth using a custom-fabricated titanium bracket and a modified SmartPeg. Methods: Sixteen systemically healthy patients (10 males, six females) and 94 single-rooted permanent teeth with varying mobility grades were included. The tooth mobility was assessed using the Miller Mobility Index, Periotest M, and resonance frequency analysis (RFA) with the Osstell Beacon device. For the Osstell measurements, a custom titanium bracket bonded to the buccal tooth surface allowed for the placement of a modified SmartPeg. Each tooth was measured twice under standardized conditions, and mean values were recorded. The statistical analyses included Spearman correlation analysis, Cohen’s kappa for agreement with Miller categories, and intraclass correlation coefficients (ICCs) to assess the measurement repeatability. Results: The mean Periotest value was 12.70 ± 13.69, and the mean ISQ (implant stability quotient) value was 69.45 ± 19.37. The repeated measurements demonstrated excellent intra-examiner repeatability for both devices (ICC > 0.95). The Periotest values showed substantial agreement with the Miller mobility grades (κ = 0.763; p < 0.001), whereas the Osstell values demonstrated weak agreement with these ordinal categories (κ = 0.094; p = 0.048). A strong negative correlation was observed between the Periotest and Osstell measurements irrespective of the scales (r = −0.865; p < 0.001). Conclusions: In natural dentition, the resonance frequency analysis demonstrated reproducible measurements under controlled experimental conditions and showed measurable associations with conventional mobility assessments. However, the method remains investigational. The findings do not establish clinical validity for the routine assessment of natural tooth mobility. Further studies with larger sample sizes and statistical models accounting for patient-level clustering are required before clinical implementation can be considered. This study is registered at ClinicalTrials.gov (NCT07188168). Full article

Wooden, nature-based barrier structures are widely implemented after wildfire in Mediterranean forests to reduce runoff connectivity and trap sediment, yet their ecological footprint on early plant recovery remains poorly quantified in Greece. We assessed two-year vascular plant recovery in forest landscapes burned during the 2021 wildfire season (Parnitha, Attica; Mavrolimni, Corinthia/Peloponnese) using repeated field surveys in 2022 and 2023. Sixteen permanent plots were established within operational rehabilitation works and assigned to the dominant structure types: wattles (brush/branch piles), contour-oriented hillslope log barriers, and channel log dams. In each year, vascular plant composition and recovery endpoints (species richness and diversity indices, density, cover, and aboveground biomass) were quantified using standardized quadrat sampling. Vegetation cover and biomass increased strongly from 2022 to 2023 at both sites, indicating rapid early reassembly. Against this dominant year effect, structure type was associated with pronounced biodiversity and compositional differences, most clearly in Parnitha where log barriers exhibited markedly reduced diversity in 2022 and community turnover patterns differed among structures. Plot-level PERMANOVA on Bray–Curtis dissimilarities calculated from log(x + 1)-transformed abundances did not detect a statistically significant structure type effect in either year (p > 0.05), whereas descriptive Bray–Curtis heatmaps suggested compositional contrasts among structure type × year combinations. Indicator–species analysis further identified a limited set of taxa associated with specific structures, suggesting provisional structure-linked microsite filtering during early assembly. By quantifying community composition and indicator taxa alongside structural recovery, this study provides operational-scale evidence that common wooden post-fire measures may be associated with early biodiversity signals in the first two years after fire, although these patterns should be regarded as provisional given the short monitoring period and limited replication. Incorporating these signals into post-fire land management can improve intervention design and placement, aligning risk reduction with biodiversity recovery in Mediterranean landscapes. Full article

In the aviation sector, there is a growing demand for high-specific-power electrical machines to realize More Electric Aircraft (MEA). The goals for these machines were set by the National Aeronautics and Space Administration (NASA) as 1 $\mathrm{M}$$\mathrm{W}$ power, >13 kW kg⁻¹ of power density, and efficiency >96%. To address these requirements, this paper proposes an electromagnetic design of a high-speed, power-dense, 1 $\mathrm{M}$$\mathrm{W}$ radial-flux Permanent Magnet Synchronous Machine (PMSM) for aerospace propulsion applications that achieves NASA targets. Achieving high-specific-power objectives necessitates geometry optimization that simultaneously minimizes motor mass while maximizing output power. This paper presents a faster optimization algorithm that hybridizes Genetic Algorithm and Artificial Neural Network (ANN)-based surrogate modeling to optimize the motor for multi-objective goals. The proposed framework employs a multi-objective approach targeting maximum torque output and efficiency within a minimum motor mass. This approach, using an ANN-based surrogate, significantly reduces optimization time by saving 95% of the time compared to FEM simulations. The optimized 1 $\mathrm{M}$$\mathrm{W}$ motor attains 98% efficiency and an active power density of 24.87 kW kg⁻¹. The various stages of the optimization are presented in detail and a comparison of the time saving using the proposed algorithm is outlined. To demonstrate the feasibility of design, a detailed electromagnetic analysis, stator thermal analysis with a jet impingement design, and magnet demagnetization risk analysis were also presented. Full article

Permanent magnet synchronous motor (PMSM)-based servo actuators are fundamental to high-performance electromechanical systems. However, in energy-sensitive aerospace applications, the impact of tracking error on system-level efficiency remains insufficiently quantified. This paper establishes an energy-oriented analytical framework linking PMSM tracking accuracy to vehicle-level energy consumption and flight range. By employing a specific mechanical energy formulation, we demonstrate that tracking deviations modify aerodynamic drag and introduce additional dissipative work. Specifically, the accumulated dissipation is shown to admit a lower bound proportional to the integral of the squared tracking error, from which a range degradation bound is derived. These results reveal that “tracking-error energy” imposes a fundamental limit on achievable flight distance. A Lyapunov-based analysis further proves that minimizing this error energy reduces total aerodynamic dissipation without requiring modifications to propulsion scheduling or guidance laws. Numerical simulations comparing a conventional sliding mode controller with an advanced fuzzy-adaptive nonsingular terminal sliding mode controller confirm that enhanced servo precision directly improves velocity retention and range performance. This framework offers practical insights for designing energy-aware PMSM control strategies in energy-constrained aerospace platforms. Full article

High-speed operation is a key pathway to higher power density in modern EV traction systems, and multi-parameter optimization is essential for enhancing its high-speed performance. This study investigates a 20,000 r/min interior double-V permanent-magnet flat-wire motor via finite-element simulations to systematically examine the effects of multiple interacting parameters—including flat-wire layer number, stator slot geometry, magnet grade, and rotor magnetic barrier angle—on the electromagnetic performance under high-speed operating conditions. The results indicate that increasing winding layers significantly reduces high-speed torque; an eight-layer design decreases torque by about 50% compared to a four-layer one, while a six-layer arrangement offers a favorable torque-loss trade-off. Wider slots lower the average torque but reduce torque ripple by approximately 27%, whereas deeper slots increase tooth flux density and reduce efficiency. Higher-grade magnets enhance air-gap flux and torque at elevated cost. Rotor magnet angle optimization reveals a trade-off between peak torque and ripple, with a symmetric 100°/100° design achieving balanced performance. These findings clarify structural–control interactions and support the multi-objective design of high-speed flat-wire permanent-magnet motors. Full article

This work experimentally evaluates the geometry-driven structural efficiency and normative performance of sandwich-type composite roofing tiles composed of a miriti wood core and fiberglass-reinforced polymer faces. Trapezoidal-profile tiles were manufactured by hand lay-up and assessed according to ABNT NBR 16753, including visual inspection, fiber content, water absorption, apparent flexural behavior, deformation resistance, and impact resistance. The miriti core exhibited an extremely low mean density of 0.091 ± 0.008 g/cm³ (CV ≈ 8.8%), enabling lightweight sandwich configurations with an average overall thickness of approximately 8 mm. Fiberglass contents ranged from 27.5% to 32.1% by mass. Sealed sandwich specimens showed median water uptake values of approximately 2.5% after 2 h and 6.0% after 24 h immersion. Deformation resistance tests indicated admissible deflections of 15.0–15.75 mm (L/40), supported by applied masses between 39.6 and 104.3 kg (≈388–1023 N) without rupture or permanent damage. Apparent flexural stresses ranged from 6.7 to 9.3 MPa, with apparent moduli between 0.7 and 1.9 GPa. All tiles achieved 100% approval in deformation, impact (2–8 J), and visual criteria. The results demonstrate that geometric effects dominate structural performance, validating miriti wood as an efficient and sustainable core for normatively compliant composite roofing systems. Full article

Background: Immune checkpoint inhibitors (ICIs) such as nivolumab have transformed the treatment landscape of metastatic non-small cell lung cancer (NSCLC). We aimed to evaluate survival outcomes of patients who developed immune-related adverse events (irAEs) that required permanent treatment discontinuation. Methods: This national, multicenter study included 25 patients with metastatic NSCLC from four tertiary oncology centers in Turkey. All patients received nivolumab monotherapy and discontinued treatment because of irAEs. Long-term survival was analyzed using Kaplan–Meier methods and compared indirectly with historical benchmarks. Results: The median overall survival (OS) was 35.73 months (95% CI: 30.06–41.40). The 2-year and 5-year OS rates were 78.9% and 27.0%, respectively. Median progression-free survival (PFS) was 16.23 months. Pneumonitis was the most frequent irAE (48%). Liver metastases significantly reduced OS (23.93 vs. 38.50 months, p = 0.005). In univariate analysis, ECOG 2 status (HR:22.07), bone metastases (HR:3.52), and subsequent systemic therapy (HR:30.19) weresignificant predictors of progression. Conclusions: Patients with metastatic NSCLC who discontinue nivolumab due to irAEs achieve notable survival outcomes, suggesting that treatment-limiting toxicity may signal a robust and durable antitumor immune response. These findings, though limited by a small cohort, highlight a distinct responder phenotype in real-world clinical practice. Full article

Background: Examining the relationship between burnout and absenteeism is important for understanding how chronic occupational stress translates into economic costs, reduced productivity, and deterioration in the health of nursing staff. The aim of this study was to evaluate absenteeism among nursing staff and its association with burnout from a gender perspective. Methods: A total of 154 nursing professionals with permanent contracts were included. An interview was conducted, which included the collection of sociodemographic data, characteristics related to their employment status, and the Maslach Burnout Inventory questionnaire in its Spanish-validated healthcare personnel version. The absenteeism rate was calculated using information from the hospital’s human resources department. The Mantel–Haenszel test was used to identify the association between burnout and absenteeism from a gender perspective. A p-value < 0.05 was considered statistically significant. Results: The prevalence of burnout was 70.1%; 52.6% reported absenteeism in 2024. The general nursing category was significantly associated with burnout (p = 0.039). Although no association was found between burnout and overall absenteeism, holding multiple jobs was identified as a determinant of partial absenteeism (p < 0.05). The hospital absenteeism rate was 4.8%. No statistically significant difference was found between burnout, gender, and absenteeism, with an adjusted odds ratio of 1.386 (95% CI: 0.75–2.65) after controlling for the effect of gender (χ²_MH = 0.672, df = 1, p = 0.412). Conclusions: Nursing staff present a critical level of burnout. No statistically significant difference was found between burnout, gender, and absenteeism, which could indicate that gender roles in the workforce may be changing in our population. Full article

To address the issues of poor control performance, synchronization defects, and instability in existing multi-pole permanent magnet synchronous motor (PMSM) control systems using PI control, this paper proposes an optimized control strategy combining Linear Active Disturbance Rejection Control (LADRC) with Capuchin Search Algorithm (CapSA). The proposed approach first implements LADRC in the PMSM speed loop, where the CapSA algorithm is applied to tune LADRC parameters, significantly reducing overshoot, enhancing the disturbance rejection capability, and improving the system stability. Secondly, by modifying the traditional deviation coupling structure and introducing an error factor to strengthen dynamic synchronization performance among multiple motors, the system’s control accuracy and robustness are effectively enhanced. Finally, a simulation model is established using MATLAB/Simulink for comparative experiments under various operating conditions. The results demonstrate that the proposed CapSA-LADRC control strategy significantly reduces speed overshoot and synchronization errors while exhibiting superior dynamic response and disturbance rejection capabilities, providing a reliable solution for practical engineering applications. Full article

Long-term safety assessment of deep geological repositories for spent nuclear fuel requires explicit evaluation of thermo-mechanical (TM) processes induced by decay heat and their influence on fractured host rock. A safety-relevant, though low-probability, scenario concerns shear reactivation of fractures intersecting deposition holes, which could compromise canister integrity if displacement exceeds design limits. This study presents a three-dimensional discrete element modelling approach to analyze the thermal evolution of the Forsmark repository (Sweden) and the associated long-term response of a discrete fracture network (DFN) during the post-closure phase. The model explicitly represents repository panel, deterministic deformation zones, and a stochastically generated fracture network embedded in a bonded particle assembly representing the rock for Particle Flow Code (PFC) numerical simulations. Time-dependent heat release from spent nuclear fuel canisters is implemented using a physically based decay power function. A deposition panel-scale heat-loading formulation accounts for deposition-hole and tunnel spacing. Two emplacement scenarios are analyzed: (a) a simultaneous all-panel heating scenario, used as a conservative bounding case, and (b) a sequential panel heating scenario representing staged emplacement and closure. The simulations show that temperature and thermally induced stress evolution are sensitive to the emplacement and closure sequence. Sequential heating produces a more gradual thermal build-up and lower peak temperatures than simultaneous heating, indicating that thermal and stress perturbations in the host rock can be influenced not only through repository design, but also by operational strategy. Thermally induced fracture shear displacement displays a systematic temporal response. Fractures located within the deposition panel footprint develop shear displacement rapidly during the early post-closure period, reaching peak values at approximately 200 years, followed by gradual relaxation as temperatures decline. The average peak shear displacement on fractures is on the order of 2–3 mm, while fractures outside the panel footprint show smaller early-time displacements and a more prolonged long-term response. All simulated shear displacements remain more than one order of magnitude below the commonly cited canister damage threshold for Forsmark of approximately 50 mm, even for the conservative simultaneous heating case. These results indicate that thermally induced fracture shear is unlikely to cause direct mechanical damage to canisters. At the same time, the persistence of residual shear displacement after heating implies permanent fracture dilation, which may influence long-term hydraulic properties and indirectly affect processes such as groundwater flow and canister corrosion. The modelling framework and results presented here were conducted for review purposes independently from the Swedish safety case, and provide a mechanistic basis for evaluating thermally induced fracture deformation in crystalline rock repositories and contribute to bounding the role of thermo-mechanical processes in the safety assessment of spent nuclear fuel disposal at Forsmark. Full article

Background. The Planas Functional Masticatory Angle [PFMA] is a functional parameter describing mandibular trajectory during mastication. Its variation across dentition stages may reflect cross-sectional physiological functional adaptation during growth. Methods. A cross-sectional pilot study recruited 30 patients [10 per group: deciduous, mixed, permanent dentition] from a university dental clinic. PFMA was measured using a standardized intraoral photographic protocol, with intra-examiner reliability assessed [ICC > 0.9]. Molar relationships were classified per Angle’s classification. PFMA differences across dentition stages were analyzed using one-way ANOVA, and molar class distributions were evaluated with chi-square tests [p < 0.05]. Results. PFMA values decreased significantly from deciduous [64.7° ± 6.9] to mixed [55.5° ± 7.8] and permanent dentition [47.2° ± 9.8] [ANOVA, p < 0.001]. Post hoc analysis revealed significant differences between deciduous and permanent stages. No significant right–left PFMA differences were observed. Class I molar relationships predominated [70%], and no significant association was found between PFMA and molar class. Conclusions. This pilot study suggests PFMA decreases with dentition progression, reflecting physiological occlusal adaptation. Class I predominance supports functional symmetry, but PFMA-molar class associations require larger samples. Longitudinal studies are needed to further explore the clinical applicability of PFMA as a functional descriptor of masticatory adaptation. Full article

Axial Flux Permanent Magnet Synchronous Motors (AFPMSMs) are gaining increasing attention for their application in electric vehicle (EV) drive systems. Their high torque density and compact axial geometry make them attractive for high-performance EV drive systems. However, cogging torque remains a major challenge, degrading low-speed drivability, noise performance, and control stability. This article proposes a magnet skew on rotor modulation structure using a genetic algorithm (GA) to reduce cogging torque in AFPMSMs utilizing a 12/15 non-integer pole/slot arrangement. The objective of optimization is to simultaneously reduce cogging torque under identical electromagnetic constraints. A complete three-dimensional finite element model (3D-FEM) incorporating nonlinear magnetic material properties has been developed to evaluate the electromagnetic field distribution and torque components. The results indicate that a 12/15 non-integer pole/slot arrangement improves harmonic distribution and extends the operating range with lower cogging torque compared to integer pole/slot designs. Combined with GA-optimized skew angles, this reduces peak-to-peak cogging torque to less than 50%. This design is ideally suited for the traction requirements of electric vehicles, including premium electric vehicles where smooth operation at low speeds is critical. Full article

The gimbal servo system in a control moment gyroscope (CMG) is critical for high-precision spacecraft attitude control, where comprehensive performance testing and evaluation are essential for ensuring spacecraft reliability and service life. Traditional motor testbenches exhibit limitations, whereas the electric motor emulator (EME) based on power electronic converters is a promising alternative for testing extreme operating conditions, such as ultra-low speed operation and fault scenarios. However, existing EME control methods suffer from limited system bandwidth and insufficient emulation accuracy, which limits their applicability. To address these issues, this paper proposes an improved current control strategy for the ultra-low speed permanent magnet synchronous motor (PMSM) emulator. First, a mathematical model of the EME based on the topology of the voltage source converter is established. Then, based on the deadbeat control concept, a deadbeat predictive current control (DPCC) strategy is developed to enhance the dynamic performance. Furthermore, to suppress the parameter mismatch disturbance, an optimization scheme based on a cascaded extended state observer (CESO) is introduced. The first-stage ESO is applied to estimate and compensate for total disturbances, while the second-stage ESO is a supplement to suppress the remaining disturbances in the EME system, which improves the robustness of the DPCC controller. Finally, the effectiveness of the improved emulation accuracy of the proposed method is verified through experiments. Full article

The integration of vertical greenery systems (VGSs) into existing reinforced concrete (RC) buildings raises questions regarding interface kinematics and the permanent displacement of soil-retaining elements under seismic excitation. This study experimentally investigates the residual displacement of façade-mounted living walls and rooftop planter pods anchored to a deficient RC frame under shake table excitation. A 1:3 scale reinforced concrete frame was tested in two distinct phases: initially as a deficient, unretrofitted structure (Phase A), and subsequently as a retrofitted system integrated with vertical greenery elements (Phase B). High-precision terrestrial laser scanning (TLS) was employed before and after successive seismic excitation stages to generate dense three-dimensional point clouds. Cloud-to-cloud comparison techniques were used to quantify global structural displacement and local kinematic behavior of greenery components, while results were validated against conventional displacement sensors. The RC frame exhibited millimeter-scale permanent displacements consistent with draw-wire measurements. In contrast, planter pods demonstrated configuration-dependent behavior, including up to 8 cm translational sliding and rotational responses reaching 13° under repeated excitation, whereas living wall panels remained stable. Notably, a 95% reduction in point cloud density reproduced global deformation patterns with an RMSE of 3.03 mm and quantified peak displacements with only ~2% deviation from full-resolution results. The findings demonstrate the capability of TLS-based monitoring to detect differential kinematic behavior of integrated VGSs, while highlighting the variability in performance of friction-based rooftop anchorage utilizing different robust planter pod fixing systems. Full article

Asphalt pavements are frequently subjected to fatigue cracking, rutting, and surface wear, which accelerate maintenance needs and shorten service life. This study evaluates the performance enhancement of NHA Class B dense-graded asphalt mixtures (12.5 mm NMAS) prepared with a 60/70 penetration grade binder through carbon fiber (CF) reinforcement. Chopped fibers (~12.7 mm) were incorporated via the dry mixing process at dosages of 0.5%, 1.0%, and 1.5% by binder weight. The results indicate that the 1.0% CF mixture delivered optimal performance, with ITS increasing by 51.9%, Marshall stability improving by 38.4%, resilient modulus rising by 42.6%, and rut depth decreasing by 69.2% compared to the unmodified control. Dynamic stability reached 33,750 passes/mm, demonstrating substantial resistance to permanent deformation. Statistical analysis using one-way ANOVA confirmed that all improvements were significant (p < 0.05). Despite a ~6.7% increase in initial cost, the CF-modified mix exhibited strong economic viability, achieving a benefit–cost ratio of 4.79 and significant life-cycle savings over 20 years. These findings underscore carbon fiber as an effective modifier for developing durable, high-performance asphalt composites with reduced maintenance requirements. This work contributes to the advancement of smart and sustainable pavement technologies for resilient transportation infrastructure. Full article