Search Results (411)

Context: Prosthetic rehabilitation of acquired maxillary defects with Maxillary Resection Prostheses (MRPs) remains biomechanically challenging, particularly in partially edentulous patients, where conventional clasp-retained designs often yield suboptimal retention, stability, and functional outcomes. Research Gap: The integration of telescopic crown systems with semi-precision attachments incorporating a rotational latching mechanism has not been previously described as a unified approach to optimise load distribution and prosthesis stability in maxillary defect rehabilitation. Objective: To describe and clinically evaluate a novel prosthetic design combining telescopic crowns and a semi-precision rotational latching attachment to enhance retention, stability, and functional performance of MRPs. Methodology: A 31-year-old patient with a unilateral maxillary defect following partial maxillectomy presented with an unstable interim prosthesis and impaired speech and mastication. A definitive MRP was designed using telescopic crowns on the remaining dentition to establish a controlled path of insertion and improved axial load transfer. A semi-precision attachment with a key–keyway rotational latching mechanism was incorporated into the secondary framework to engage specific undercuts while minimising lateral forces on abutment teeth. A provisional prosthesis was used for 3 months to evaluate base extension, phonetics, and functional parameters before fabrication of the definitive prosthesis. Results: Serial follow-up at 1, 3, and 6 months demonstrate consistent prosthesis stability, precise seating, and favourable retention. Marked improvements were observed in speech intelligibility, masticatory efficiency, and patient-reported comfort. Conclusions: This combined prosthetic strategy represents a novel and biomechanically optimised approach for the rehabilitation of partially edentulous maxillary defects, with promising clinical and functional outcomes. Full article

The excavation of deep shafts using Vertical Shaft Sinking Machine (VSM) technology in stratified soft soils involves complex soil-structure interaction (SSI) mechanisms that are often oversimplified by conventional numerical approaches. This study develops a robust three-dimensional numerical framework to investigate ground deformation induced by VSM operations, explicitly incorporating the phased construction sequence, segmental lining installation, and site-specific stratigraphy. The model is calibrated and validated against high-resolution field monitoring data, employing a prediction envelope approach and statistical performance metrics (RMSE and $R^2$). The results suggest that ground response during VSM excavation is predominantly stiffness-controlled under the investigated conditions. Mobilized shear stresses remain significantly below the available soil capacity, indicating that deformation under serviceability conditions is driven by progressive strain accumulation. Horizontal displacement profiles suggest a relatively stable depth of influence, indicating that the excavation process amplifies deformations within a pre-established domain without significant deep-seated propagation. Sensitivity analyses indicate soil stiffness modules ($E_{50},E_{oed},E_{ur})$ and the SSI interface factor ($R_{inter}$) as the primary drivers of deformation magnitude. Furthermore, stratigraphic contrasts specifically clay-sand sequences, act as a mechanical filter, concentrating strains in soft layers while limiting vertical propagation through stiffer strata. The proposed framework provides a mechanically coherent basis for serviceability-oriented design, deformation prediction, and risk-mitigation strategies for mechanized shafts in saturated soft ground. Full article

The transition phase often causes athletes to lose the benefits of warm-up, so this study aimed to assess the effects of two re-warm-up protocols and a control condition without re-warm-up on 100 m freestyle performance and the kinematic variables (stroke length (SL), stroke rate (SR), and stroke index (SI)), subjective perception of effort (RPE), and physiological variables (heart rate (HR), temperature (T), and blood lactate concentration (La⁻)). Twenty competitive-level swimmers completed a dryland and water warm-up, followed by a 30 min transition phase and a 100 m freestyle simulation. Over 30 min, each swimmer randomly performed one of three re-warm-up protocols: control (remaining seated), dryland (explosive exercises), and water (race-pace series). The three experimental re-warm-up protocols affected 100 m freestyle performance (p = 0.019; η²p = 0.189). Post hoc comparisons showed that dryland was faster than control (−0.68%, p = 0.009), whereas no significant difference was observed between water and control (−0.52%, p = 0.234). No significant differences were observed between conditions for SR, SL, RPE, or La⁻, whereas peak HR was lower in the control. Although water did not significantly improve performance, swimmers reported more favourable sensations during the trial. In conclusion, the dryland protocol significantly improved 100 m freestyle performance, whereas the water protocol did not produce significant performance benefits under the present conditions. Full article

Falls among older adults are a major public health concern, yet collecting large-scale real fall data for radar-based detection is ethically and practically difficult. This study presents a controlled simulation-to-real feasibility study for trip-fall detection using continuous-wave (CW) Doppler radar. The method couples a physics-informed kinematic trip-fall model with a CW radar observation model to synthesize I/Q signals and Doppler spectrograms, while domain randomization varies body size, fall direction, initial velocity, sensor placement, aspect angle, amplitude, and noise. Synthetic walking and respiration data were also generated for controlled three-class classification among trip fall, walking, and seated quiet breathing. In Experiment I, the simulated spectrograms reproduced the dominant time–frequency characteristics of measured enacted trip-fall signals acquired with a 24 GHz CW radar; quantitative similarity analysis yielded a mean SSIM of 0.782 and a Doppler-ridge MAE of 24.6 Hz across five fall directions. In Experiment II, a ResNet-18 classifier trained only on simulated spectrograms achieved a macro-F1 score of 0.912 [95% CI: 0.883–0.936] on measured data from ten participants, three start locations, and eight directions. Under the present controlled evaluation, this exceeded the available real-data-trained baseline of 0.748 [95% CI: 0.691–0.805] (paired subject-level permutation test, $p=0.006$). These findings suggest that physics-informed simulation with domain randomization can reduce dependence on real trip-fall samples under limited-data conditions. The results do not establish robustness to other fall morphologies, fall-like activities of daily living, different environments, different radar devices, or embedded deployment. Full article

Magnetorheological elastomers (MREs) have recently attracted significant attention for the development of adaptive vibration isolators and absorbers. Their ability to tune mechanical properties in response to external excitations makes them promising candidates for semi-active control applications. In this study, the Generalized Maxwell model with three Maxwell branches is employed to predict variations in storage and loss moduli of isotropic MREs operating in shear mode under varying excitation frequencies and magnetic flux densities. A practical semi-active MRE-based seat vibration isolator is proposed, and a multidisciplinary design optimization problem is subsequently formulated to determine the optimal geometrical parameters of the isolator. The objective is to maximize the frequency bandwidth while satisfying constraints on weight, material magnetic saturation, and total volume. The optimization results demonstrate that the proposed adaptive isolator can achieve a significant relative increase in its natural frequency by adjusting the applied magnetic flux density, while maintaining a practical total mass. A post-optimality analysis is also conducted to investigate the influence of the upper bound on the isolator’s mass. The findings reveal a nonlinear relationship between the optimal frequency ratio and the total mass of the isolator. Finally, closed-loop control strategies based on on–off skyhook and PID control are implemented and compared to evaluate the capability of the proposed adaptive isolator to mitigate vibration and shock under varying disturbances. Full article

Current fuzzing techniques for industrial control protocols (ICPs) encounter notable challenges, including model training instability, limited sample diversity, and the inability to manage complex state dependencies in protocol interactions. To address these issues, this paper presents SD-Fuzz, a state-aware fuzzing framework that integrates a discrete denoising diffusion probabilistic model (DDPM) with an online Hidden Markov Model (HMM). The discrete DDPM is designed to generate syntactically valid and diverse protocol messages using cosine noise scheduling and Denoising Diffusion Implicit Model (DDIM) sampling, while the HMM performs unsupervised learning of state transitions from real traffic to guide the creation of logically consistent multi-step interaction sequences. The framework is evaluated on three representative Modbus/TCP slave implementations. Evaluations based on 5 h benchmark campaigns across multiple independent runs indicate that SD-Fuzz achieves a mean test case recognition rate (TCRR) of 91.3% and an HMM-inferred state transition coverage of 50.1%, exhibiting statistically significant improvements over the evaluated baselines. Furthermore, an extended 8 h vulnerability mining campaign demonstrates its capability to trigger deep-seated exceptions, including buffer overflows and protocol state violations, which are typically challenging to access using traditional stateless approaches. This work illustrates the feasibility of combining diffusion-based generation with lightweight state inference for automated vulnerability discovery in industrial control systems. Directions for future work include validation on physical programmable logic controller (PLC) hardware to acquire internal code coverage feedback. Full article

The Chutuan and Jiashan fluorite deposits are situated in the Donghai–Linshu area within the southwestern segment of the Sulu ultrahigh–pressure metamorphic belt. Both deposits share similar mineralization characteristics, with fluorite veins strictly controlled by fault structures and associated with mineral assemblages comprising fluorite, barite, quartz, and calcite. Two mineralization stages have been identified in both deposits: Stage I (quartz–fluorite–barite stage), representing the main ore–forming event, and Stage II (quartz–barite–calcite stage). This study focuses on integrated geochemical and geochronological analyses of fluorite from Stage I, providing new constraints on the genesis and metallogenic processes of these deposits. Direct Sm–Nd isotopic dating of fluorite yields an isochron age of 104 ± 16 Ma, indicating that mineralization occurred during the late Early Cretaceous. Fluid inclusion and stable isotope studies reveal that the ore–forming fluids constitute a complex hydrothermal system characterized by a wide temperature range (112–324 °C) and variable salinities (0.18–21.87 wt% NaCl eq.). The H–O isotopic compositions exhibit a distinct latitudinal trend, supporting a dominant meteoric water component. However, the presence of high–temperature, high–salinity fluid inclusions, along with a shift in some δD values towards the magmatic water field, suggests episodic mixing between meteoric water and deep–seated magmatic–hydrothermal fluids. Sr–Nd isotopic data (⁸⁷Sr/⁸⁶Sr = 0.711785–0.713424; εNd(t)= −27.7 to −27.5) potentially demonstrate that the ore–forming materials (Ca and REEs) were not derived from coeval magmatic rocks. Instead, they were primarily leached from the Precambrian Donghai Group metamorphic complex through extensive water–rock interaction. Based on these findings, the Chutuan and Jiashan deposits are classified as hydrothermal vein–type systems. Fluorite precipitation was governed by a combination of fluid cooling, water–rock interaction, and fluid mixing. Finally, a metallogenic model is established, offering important insights into the genesis of fluorite mineralization in the Sulu Orogenic Belt and analogous geological settings in eastern China. Full article

The accelerating pace of technological innovation has exacerbated the spatial misalignment between the static, supply-driven provision of educational facilities and the dynamic, demand-driven patterns of contemporary pedagogical activities. Assessing and quantifying spatial demand and the operational consumption of teaching environments pose critical challenges for facility asset management in higher education. Accordingly, rigorous investigation into the determinants of classroom spatial utilization efficiency and the formulation of evidence-based spatial optimization strategies are essential to advancing the sustainable evolution of campus infrastructure. This study takes the Zhengxin Building at Harbin Institute of Technology as a descriptive case, integrating timetable data with spatial syntax at the building scale. The scheduling data for 2943 courses in the Spring semester of 2023 was selected as the research basis. Using architectural spatial analysis tools—including space syntax theory, statistical correlation methods, and in situ observational surveys—this study extracts spatial attribute variables such as classroom area (A), seating capacity (S), floor level (F), integration (I), and space utilization efficiency metrics as primary quantitative measures. The interrelationships among these variables are examined to elucidate the principal drivers of teaching space performance. The empirical results indicate that the Overall Space Utilization Rate (OSUR) of the Zhengxin Building ranged from 20% to 50% during the study. The key findings include the following: (1) spatial utilization efficiency is positively associated with classroom scale but shows no significant relationship with integration (I); (2) after controlling for classroom type (T), per capita area index (PCAI), and integration (I), floor level (F) no longer exerts a statistically significant influence on utilization outcomes; (3) teaching spaces with higher integration and spatial entropy are more adaptable to heterogeneous instructional and extracurricular uses. The classroom type (T) directly mediates occupancy patterns and activity programming. Full article

Previous studies on healthy controls suggest the added value of thigh-based Electrocardiography (ECG), which collects data using sensors embedded in a toilet seat for unobtrusive signal acquisition. However, further evidence regarding its clinical feasibility is needed; with this work, we investigated three complementary aspects: signal quality, morphological correlation with standard ECG leads, and the system’s potential for heart rate variability (HRV) analysis in patients undergoing aortic valve replacement. This work was divided into two main phases. In the first, 32 healthy volunteers underwent simultaneous ECG recordings using both a standard 12-lead ECG system and the thigh-based system. Signal Quality Index (SQI) analysis revealed that 56.25% of the experimental signals were classified as excellent, and over 62.5% of recordings showed a strong correlation with Lead I of the clinical ECG. These findings extend the state of the art by further characterising the quality and relevance of the captured signals. In the second phase, two patients with severe aortic stenosis were monitored before and after surgical valve replacement. HRV metrics derived from the thigh-based ECG captured distinct autonomic responses: one patient showed significant postoperative improvement in global and parasympathetic modulation (increased SDNN, RMSSD, and Sample Entropy), while the other exhibited reduced variability and complexity, potentially indicating impaired autonomic recovery. These results highlight the feasibility of thigh-based ECG data acquisition for passive, longitudinal cardiac health monitoring in everyday environments and its applicability for pre- and postoperative autonomic assessment. Full article

The use of hydrogen direct injection (DI) plays a crucial role in decarbonizing internal combustion engine (ICE) technology. However, a suitable characterization of the injection process is required to control the mixture preparation before combustion, especially in the case of late injection timing. CFD modeling represents a useful tool to support experiments in addressing this goal. This study presents a numerical investigation of hydrogen DI using a swirled-type injector, seated in a constant-volume vessel. First, the selected numerical setup is validated against optical measurements of the jet penetration, demonstrating the reliability of the approach. Then, the analysis compares swirling and non-swirling configurations under different nozzle pressure ratios (nPRs) to evaluate the interaction between swirl-induced mixing and under-expanded jet structures. Results show that at lower nPR, swirl significantly alters the momentum distribution, reducing axial penetration. Instead, at higher nPR, where the H2 jets exhibit strong shock structures, the effects of swirl become negligible, with penetration and plume morphology nearly identical to non-swirling conditions. Analysis of the scalar dissipation rate showed the presence of a redistribution of mixing characteristics at low nPR due to swirl, while shock structures dominate at high nPR. This could have a significant impact on combustion and NO_x emissions in ICE operated with late injection strategies, where lower nPR are found. Full article

Minimally invasive parafascicular surgery (MIPS) represents a paradigm shift in the management of deep-seated brain tumors, enabling function-sparing resections previously limited to biopsy and/or medical therapy. Central to MIPS are structured frameworks guiding preoperative planning and intraoperative execution. The six-pillar concept—comprising imaging, navigation, atraumatic access, optics, resection, and postoperative care—provides a comprehensive approach to integrate advanced neuroimaging, tractography, tubular retractor systems, fluorescence-guided resection, and neuromonitoring to optimize functional outcomes. Five-point target-trajectory complex planning—craniotomy, outer radial corridor, inner radial corridor, target, and resection margins—translates preoperative imaging and functional mapping into a precise surgical trajectory, balancing maximal tumor resection with minimal disruption of eloquent brain structures. Preoperative assessment of tumor characteristics, vascular relationships, and cortical eloquence informs trajectory planning and intraoperative adjustments. A critical determinant of MIPS success is the intraoperative golden hour, referring to the high-risk period surrounding brain cannulation with a tubular retractor. Key principles include (1) precannulation system checks to ensure instrument readiness; (2) access injury prevention through optimized craniotomy sizing and sulcal preparation; (3) tubular-tumor targeting accuracy addressing brain and tubular translation, tumor displacement, and white-matter sleeves; and (4) intracranial pressure control strategies to minimize tissue strain and venous congestion. Overcoming this period enables a controlled resection phase guided by the above-mentioned surgical adjuncts. The six-pillar concept and five-point target-trajectory complex planning are the foundations of MIPS planning, whereas the intraoperative golden hour provides a roadmap for successful intraoperative delivery of the surgical plan. Full article

Deep-seated landslide complexes are widespread in soft-rock hill-country landscapes, yet their regional morphometric organisation and controlling factors remain insufficiently quantified. This study uses high-resolution (1 m) airborne LiDAR-derived terrain data integrated with geological and drainage-network datasets to investigate landslide complexes in the eastern Tararua District, New Zealand. A relative, unit-based morphometric framework is applied to compare terrain derivatives (including slope, aspect, and multi-scale relative relief) between mapped landslides and their host geological units. To isolate intrinsic lithological controls from geomorphic influences, the analysis is restricted to landslides occurring entirely within a single geological unit. The results indicate that lithology exerts first-order control on landslide morphometry, while fluvial incision and valley confinement regulate landslide initiation and persistence. Landslides are preferentially associated with low- to mid-order channels, indicating strong hillslope–channel coupling within a young, actively uplifting landscape. A conceptual threshold framework is proposed, showing that landslides develop where lithological susceptibility and relief amplification jointly exceed stability thresholds. By integrating geological information with LiDAR-based morphometric analysis, this study provides a transferable framework for distinguishing instability regimes and improving understanding of sediment dynamics and landscape evolution in soft-rock terrains. Full article

Land leveling deep-seated landslides for agricultural use alters soil profile integrity and soil functionality. In the mid-20th century, such interventions in the Transylvanian Basin (Romania) involved grading and converting landslide bodies into arable land. This study evaluates the consequences of interventions on soil physicochemical properties and erosion susceptibility in the case of two deep-seated landslides. Soil samples collected from leveled landslide bodies were analyzed for pH, total nitrogen, available phosphorus (P-AL), available potassium (K-AL), calcium carbonates, humus content, and texture. The results, in the case of the two studied deep-seated landslides, indicate contrasts between areas where the Ah horizon is preserved and where leveling exposed the C horizon or parental material at the surface. Exposed zones exhibit reduced nitrogen and humus content, altered textures, and higher carbonate influence, indicating lower fertility potential despite 65 years of pedogenesis. Spatial assessment using Sentinel-2-derived NDMI and USLE-based erosion modelling confirms increased moisture stress and higher erosion susceptibility in areas with exposed substratum. These findings demonstrate that the leveling of the two studied deep-seated landslide bodies, although effective in expanding arable surfaces, leads to persistent soil degradation patterns and reduced agro-ecological resilience. Sustainable cultivation of such terrains requires targeted soil conservation measures, including erosion control and adapted land management practices. The results provide important implications for land-use planning in landslide-prone agricultural landscapes. Full article

Amidst global urbanization and rising psychological stress, urban green spaces are increasingly recognized as critical infrastructure for sustainable urban development and public health. However, the mechanisms by which summer vegetation structure mediates both physiological and psychological restoration, and the interplay between these two dimensions, remain poorly understood. Understanding these mechanisms is essential for designing sustainable, health-promoting urban environments that can support growing urban populations in a warming climate. This study employed a controlled field experiment in Xi’an during summer to examine the effects of five vegetation structure types (Single-Layer Grassland, single-layer woodland, tree–shrub–grass composite woodland, tree–grass composite woodland, and a non-vegetated square) on university students’ physiological (heart rate variability) and psychological (perceived restorativeness and affective states) restoration. Following stress induction, 300 participants engaged with the green spaces through both quiet sitting and walking. The results revealed three key findings: (1) the tree–shrub–grass composite woodland consistently showed the most favorable trends other vegetation types across all psychological restoration dimensions, while also showing favorable trends in physiological recovery, underscoring the importance of structural complexity for restorative quality; (2) walking significantly enhanced physiological recovery compared to seated observation across all settings, confirming the role of physical activity as a critical activator of green space benefits; (3) correlation analysis identified a specific cross-system association: the R-R interval recovery value showed a weak but significant correlation with positive affect (PA) scores, suggesting that physiological calmness and positive emotional experience are linked, yet their weak coupling under short-term exposure indicates they may operate as parallel processes with distinct temporal dynamics. These findings indicate that the restorative potential of summer green spaces emerges from an integrated framework combining vegetation complexity and activity support. We propose that future sustainable landscape design should prioritize multi-layered vegetation structures as nature-based solutions that simultaneously enhance human well-being and urban resilience. These findings provide empirical evidence for integrating health-promoting green infrastructure into sustainable urban planning frameworks, supporting multiple Sustainable Development Goals (SDGs), including SDG 3 (Good Health and Well-being), SDG 11 (Sustainable Cities and Communities), and SDG 13 (Climate Action). Full article

This study examined temporal scalp electroencephalography (EEG) absolute power and brief self-reported psychological state measures before and after participation in a Life Story Program (LSP) in older adults. Five older women participated in the study. For each participant, pre- and post-assessments were scheduled at approximately the same time of day and included a brief four-item questionnaire and biosignal acquisition in a controlled seated environment. EEG was recorded at 500 Hz from T5 and T6 during an eyes-closed resting condition. For EEG analysis, only non-speaking segments were used; the initial 3–5 min stabilization period was excluded, and the subsequent 10 min of data were analyzed. One participant was excluded after outlier screening, resulting in a final EEG sample of four participants. EEG preprocessing included linear detrending, 60 Hz notch filtering, 0.5–50 Hz band-pass filtering, artifact rejection, and Welch-based estimation of absolute power in the delta, theta, alpha, beta, and gamma bands. Given the small sample size, all analyses were treated as exploratory. Questionnaire responses remained generally stable across assessments. No statistically significant pre–post differences were observed after false discovery rate correction, although small reductions, particularly in the gamma band, were observed. These findings should be interpreted as preliminary observations requiring confirmation in larger controlled studies with broader multichannel EEG coverage and more robust recording configurations. Full article