Search Results (2,471)

Objective: To assess the anatomical and clinical outcomes of a novel, mesh-free cerclage pectopexy technique that uses the round ligament for apical support following total laparoscopic hysterectomy in women with stage II uterine prolapse. Methods: This retrospective observational study included 120 women with stage II uterine prolapse who underwent total laparoscopic hysterectomy followed by laparoscopic non-mesh pectopexy between October 2023 and August 2024. In this procedure, the distal portion of each round ligament was fixed to the pectineal ligament using Ethibond sutures. Multiple plicating stitches were then placed to reinforce the ligament’s tensile strength, creating a biological suspension bridge between the pectineal ligament and the vaginal cuff. All patients were examined preoperatively and at 1, 3, 6, and 12 months postoperatively using the POP-Q system. Anatomical success was defined as an apical stage ≤ I at 12 months. Results: At the twelve-month follow-up, anatomical success was achieved in 95 percent of patients, with six cases of apical recurrence. POP-Q measurements showed significant improvement from baseline, and total vaginal length was preserved. Functional outcomes, including postoperative pain and dyspareunia, were favorable. Early complications were uncommon, and no intraoperative or mesh-related complications occurred. Conclusion: Round-ligament-based non-mesh cerclage pectopexy provides reliable apical support with minimal surgical morbidity following total laparoscopic hysterectomy. This technique appears to provide effective apical support with low surgical morbidity while avoiding synthetic mesh. Preservation of vaginal length and favorable short-term clinical outcomes were observed; however, longer-term comparative studies are required. Future prospective studies combining this procedure with other minimally invasive suspension techniques, such as McCall culdoplasty or uterosacral plication, may broaden its applicability to more advanced prolapse cases. Full article

Three-dimensional UAV operations require path planning methods that can jointly maintain route efficiency, threat avoidance, and trajectory smoothness under spatially distributed and time-varying constraints. To address this problem, this paper develops an integrated Dual-Layer Adaptive T-perturbation and Opposition-based Multi-Objective Particle Swarm Optimization framework, termed DATO-MOPSO, for 3D UAV path planning in complex threat environments. The method integrates a dual-layer adaptive inertia-weight and velocity-regulation mechanism with symmetric T-perturbation, an elite quasi-opposition-based learning strategy for diversity recovery and feasible local exploitation, and an archive-driven simulated annealing rule for stagnation-aware personal-best updating. A three-objective model minimizing path length, threat exposure, and path smoothness is established, and comparative experiments against MOPSO, ZAMOPSO, NSGA-II, and SPEA2 are conducted in both static and dynamic environments, together with statistical and ablation analyses. In the static scenario, DATO-MOPSO achieved the highest mean HV and stable repeated-run performance, but its IGD was comparable to ZAMOPSO with higher computational cost. In the dynamic scenario, DATO-MOPSO showed its main advantage, achieving the highest mean HV and the lowest mean IGD with statistically significant HV and IGD improvements over all baselines. Overall, DATO-MOPSO is most advantageous in time-varying complex threat environments, whereas its static-scenario advantages are accompanied by higher computational cost. Full article

Water Distribution System (WDS) pipe failures are one of the most critical issues in WDS management. In order to identify them, a machine learning approach was applied to eight years of geolocated data on pipe failures to establish priorities for WDS rehabilitation. District-level characteristics, such as network length, pressures, materials, population density, and temperature, were combined with a specific failure rate to account for differences in network size. A cost-sensitive classification approach minimized false negatives, ensuring that high-risk areas were correctly flagged. Among all models analyzed the best performance was achieved by Naive Bayes, which reliably predicted priority districts for proactive maintenance, supporting pipeline renewal strategies. Full article

This paper presents the results of apatite fission-track (AFT) and zircon fission-track (ZFT) analysis (dating) on samples collected from the surface exposures of six Precambrian intrusions in the southeastern Fennoscandian Shield: the Avdeevo and Shala dykes, the Valaam sill, the Salmi and Wiborg batholiths, and the Kuznechenskii massif. The short mean track lengths in apatite (10.7–13.5 μm) indicate that the studied rocks resided for a prolonged period within the apatite partial annealing zone (APAZ, 60–120 °C). We suggest that the AFT ages obtained from two of the granitic intrusions—the Salmi batholith and the Kuznechenskii massif—are apparent due to α-radiation-enhanced annealing (REA), as evidenced by an inverse correlation between single-grain AFT age and effective uranium (eU) concentration, and high dispersion and a negative chi-square test. An attempt to minimize the contribution of the REA effect to the AFT data for the Salmi batholith allowed its AFT age to be estimated as 1251 ± 125 (2σ) Ma, but the same approach was unsuccessful for the Kuznechenskii massif. In contrast, the mafic intrusions show no such correlation and yield reliable AFT ages: the Avdeevo dyke, 1040 ± 104 Ma; the Shala dyke, 1145 ± 89 Ma; and the Valaam sill, 1184 ± 78 Ma. The AFT data from the Wiborg batholith can be regarded as preliminary only. The most reliable AFT ages and thermal evolution models for the studied intrusions are similar and indicate prolonged exhumation of the intrusions to the surface over more than 1 billion years, with a marked increase in cooling rates around 300 Ma, which possibly has far-field causes, such as mantle dynamics related to the initial fragmentation of Pangea. Our data, as a first approximation, suggest a similar tectono–thermal evolution for intrusions located both within the northeastern margin of the Svecofennian orogen and on the Archean Karelian craton. Full article

Background and Objectives: Assessing knee extensor (KE) strength is important for detecting muscle weakness in older adults, yet dynamometry is often impractical in community settings. This study examined whether smartphone-derived kinematics during the Five Times Sit-to-Stand Test (FTSST) could predict seated isometric KE strength. Materials and Methods: A cross-sectional study included 105 community-dwelling older adults (68.19 ± 5.85 years). A smartphone application extracted rising time, vertical velocity, and smartphone-estimated relative vertical power during the FTSST. KE strength was measured as maximum voluntary isometric contraction (MVIC) using fixed-frame dynamometry with a Lafayette dynamometer head. Bioelectrical impedance-derived body composition variables were reported descriptively but excluded from the primary prediction models to maintain a transparent movement-based model independent of device-specific body-composition estimates. Hierarchical regression models used smartphone-derived variables and transparent non-BIA covariates. Agreement was examined using Bland–Altman analysis. Results: Smartphone-estimated relative vertical power showed the strongest correlation with MVIC (r = 0.787, p < 0.001). The combined model including sex, age, femur length, and smartphone-estimated relative vertical power explained 71.6% of MVIC variance (adjusted R² = 0.716, SEE = 3.276 kg), outperforming vertical velocity, rising time, and total FTSST time models. Internal validation using repeated 10-fold cross-validation showed CV-R² = 0.701, CV-adjusted R² = 0.689, CV-RMSE = 3.343 kg, and CV-MAE = 2.739 kg. Bland–Altman analysis showed minimal mean bias (0.00 kg), 95% limits of agreement from −6.296 to 6.296 kg, and significant proportional bias (slope = −0.172, p = 0.002), indicating overestimation in weaker individuals and underestimation in stronger individuals. Conclusions: Consistent with our hypothesis, smartphone-estimated relative vertical power was the strongest kinematic predictor of seated isometric KE strength among the evaluated FTSST-derived variables. This approach may support community screening and monitoring, but it should not replace standardized dynamometry for precise individual-level strength quantification. Full article

This study presents a combined numerical–statistical framework based on the Extended Finite Element Method (XFEM) and the Taguchi optimization method to assess the fracture behavior of pressurized pipelines containing external longitudinal cracks. XFEM is employed to evaluate the local fracture response without remeshing, while the Taguchi method is used to quantify the influence of key parameters and identify an optimal configuration with a limited number of simulations. The control parameters considered are internal pressure, initial crack length, and wall thickness, and the evaluated mechanical responses include circumferential stress, the J-integral, and the stress intensity factor. The optimization follows the “smaller-the-better” criterion to minimize stress concentration, fracture-driving forces, and the risk of structural failure. Results indicate that internal pressure predominantly affects circumferential stress and the stress intensity factor, whereas wall thickness has the greatest influence on the J-integral. The optimal parameter combination is determined through signal-to-noise ratio analysis and validated using the delta method, confirming the robustness of the selected configuration. A confirmation simulation performed with XFEM demonstrates a consistent reduction in all fracture-related mechanical responses, highlighting the effectiveness of the proposed approach. It should be noted that the present study is limited to the static fracture assessment of external cracks and does not address fatigue crack growth or fatigue life prediction. Overall, the proposed methodology provides a decision-support tool for pipeline integrity management by integrating numerical fracture mechanics analysis with robust design optimization, thereby contributing to safer operation and improved structural reliability. Full article

Background: Endometrial cancer is the most common gynecologic malignancy in North America, with over 8000 new diagnoses in 2022 alone. Surgical management is the mainstay of treatment, with a shift towards the use of minimally invasive surgery, including laparoscopic and robotic techniques. Therefore, our study aims to compare the surgical and oncologic outcomes of hysterectomy approaches for patients with endometrial cancer. Methods: We have used a retrospective design to review all the endometrial cancer cases from Kingston Health Sciences Centre between January 2017 and November 2022. Variables were collected and categorized. Surgical outcomes were compared based on the route of surgery. Kaplan–Meier and Cox proportional hazard models were used to compare recurrence-free and overall survival. Results: A total of 341 cases were included in this review. One-hundred-fifty-two (44.6%) of these cases were minimally invasive surgeries (total laparoscopic, laparoscopic-assisted vaginal and robotic-assisted hysterectomies) and 189 (55.4%) were open hysterectomies. The early complication rates (p < 0.001) and length of stay (p < 0.001) were lower in the laparoscopic group. Despite the abdominal group including more advanced cases, there were no differences in recurrence-free and overall survival between the groups (p = 0.39; p = 0.85). Conclusions: Minimally invasive hysterectomy approaches result in improved surgical outcomes, while oncologic outcomes remain similar across techniques. Full article

Background/Objectives: textbook outcome (TO) is an established surgical quality measure, but failure is recognized only after postoperative events. We evaluated whether intraoperative stress burden (blood loss, fluid administration, and transfusion) is associated with adapted TO attainment and overall survival (OS) after curative-intent gastrectomy. Methods: in 2352 patients with gastric adenocarcinoma (2010–2020), an intraoperative stress burden score summed three binary components (blood loss > 200 mL, fluid > 68 mL/kg, and any transfusion) and was categorized as low, intermediate, or high. Adapted TO required R0 resection, ≥15 retrieved nodes, no Clavien–Dindo ≥ III complication, no unplanned reoperation, no 30-day mortality, and length of stay ≤ 12 days. Multivariable logistic and Cox models, overlap weighting, and sensitivity analyses were applied. Results: the median age was 60 years; 66.9% were male, 67.7% had pT3–4 and 42.0% pN2–3 disease, and 30.1% underwent minimally invasive surgery. TO attainment declined with increasing burden (78.0%, 70.5%, and 65.2%; p < 0.001). Intermediate and high burden were associated with TO failure (adjusted odds ratios 1.50 and 1.68), though the high-burden association was attenuated after adjusting for operative time. High burden was associated with worse OS (adjusted hazard ratio 1.36; 95% CI 1.15–1.62; 1.44 after overlap weighting). Risk was time-varying—strongest in the first postoperative year (HR 2.03), persisting at 12–60 months (HR 1.54), and absent beyond 60 months. Conclusions: higher intraoperative stress burden identified patients with lower adapted TO attainment and increased early mortality after gastrectomy. External validation is needed. Full article

In this paper, an Adaptive Improved Cuckoo-Catfish Optimizer (AICCO) is proposed for smooth and collision-free mobile robot path planning in static and dynamic environments. The proposed AICCO enhances the original Cuckoo-Catfish Optimizer (CCO) by integrating chaotic opposition-based initialization, nonlinear adaptive control, elite-guided search, strong elite preservation, memetic local refinement, and stagnation-based opposition repair. A weighted-sum scalarized fitness function is formulated to minimize path length and turning-angle variation while maximizing obstacle clearance. The proposed method is evaluated using 23 benchmark functions and further validated in static, dynamic, and nonlinear/reactive obstacle navigation scenarios. The benchmark results show that AICCO achieves the best overall rank among the optimizers compared. In the static planning scenario, the method achieves zero collision penalty and a minimum clearance of 0.785565. In the dynamic online replanning scenario, it achieves zero collisions with a minimum clearance of 1.514250. An additional nonlinear/reactive dynamic scenario further demonstrates that the proposed method can maintain collision-free navigation under more complex obstacle motion. Full article

The role of mangrove root exudates in mediating the nitrogen cycle, particularly under high dissolved inorganic nitrogen (DIN) input, in coastal ecosystems remains unclear. This research investigated variation in the root exudates, and nitrogen transformation and output, in constructed mangrove wetlands planted with Kandelia obovata under high, moderate, and low nitrogen-input levels (PCWs-H, PCWs-M, and PCWs-L, respectively). PCWs-H promoted increased root density and biomass accumulation, enhancing soil nitrogen sequestration, whereas PCWs-L induced greater specific root length, specific root surface area, and number of root tips. These changes directly influenced denitrification efficiency. Hydroxymethoxyphenylcarboxylic acid-O-sulfate and Arg-Ser released in root exudates under PCWs-H might act as potential denitrification inhibitors, thereby suppressing denitrifiers and impairing dissolved nitrogen purification. Elevated nitrogen loading predominantly limited denitrification, resulting in relative NO₃⁻-N removal rates of PCWs-H < PCWs-M < PCWs-L (p < 0.05). Compared with PCWs-H and PCWs-L, the enhanced soil organic nitrogen storage under PCWs-M was associated with flavonoids in root exudates. Metagenomic analysis showed that denitrification was the dominant nitrogen removal pathway. Nitrogen loading influenced the effects of root exudates on the microbial community. Under PCWs-H, triterpenoids promoted norBC and nirK/S abundance but depressed amoABC abundance. Sterols and flavonoids in exudates under PCWs-L depressed nosZ abundance, instead activating dissimilatory nitrate reduction to ammonium. Compared with PCWs-H and PCWs-L, N₂O emissions were minimal under PCWs-M. This study revealed that mangrove root exudates mediate the nitrogen cycle in mangrove wetlands, providing a theoretical basis for local authorities to manage DIN inputs and mitigate N₂O emissions. Full article

This study develops novel mathematical models to capture the complexities of international land logistics by extending the classical Traveling Salesman Problem (TSP) within a symmetry-aware optimization framework. A focused review of literature provides the theoretical basis for model formulation and highlights the limitations of conventional distance-only approaches. In international transport, shorter routes are often assumed to reduce energy use; however, this assumption overlooks the decisive influence of travel time and traffic variability. In this context, symmetry offers a useful analytical lens, as balanced relationships among distance, time, and fuel consumption can reveal more efficient logistics structures. Accordingly, two models are proposed: the Traditional Traveling Salesman Problem in terms of Distance Concentration (TTSPD), which minimizes route length, and the Extended Traveling Salesman Problem in terms of Distance and Time Concentration (ETSPDT), which jointly considers distance, travel time, and fuel consumption. Furthermore, TTSPD was employed to validate ETSPDT, since it is based on the traditional TSP. Both models are solved exactly using the Solver Add-in in Microsoft Excel 2024 with data derived from Google Maps. The results show that ETSPDT achieves superior energy efficiency and average speed, demonstrating the practical value of multidimensional, symmetry-informed optimization for sustainable supply chain and logistics management. Full article

The experimental determination of the relationships between the stress distribution zone in the soil layer and the parameters of tillage working bodies is a labor-intensive process. Therefore, preliminary mathematical modeling of this process is recommended to minimize the total number of experiments. The research was conducted using the principles of classical mechanics and soil mechanics. Using an equation proposed by J. Boussinesq, a graphical–analytical method was developed to evaluate the stress state in the soil layer induced by a dihedral wedge. This method incorporates both the geometric parameters of the dihedral wedge and the physico-mechanical properties of the soil. A direct proportional relationship was established between the length of the dihedral wedge and the total area of the deformed soil mass. Specifically, increasing the length of the dihedral wedge by 83% (from 0.05 to 0.30 m) resulted in an 80% increase in the area of the deformed soil mass (from 0.02 to 0.10 m²). The proposed graphical–analytical method can be employed in the design of tillage implements. The results we obtained are consistent with the patterns previously reported by other researchers. The findings were used in the development of various types of flat-cutting working tools for shallow and deep tillage. Full article

Background/Objectives: Perioperative chemo-immunotherapy (CHT-IO) has emerged as a standard treatment strategy for resectable stage II–IIIB NSCLC. However, data regarding surgical feasibility, mini-invasive surgery rates, perioperative outcomes, and postoperative complications in real-world single-center experiences remain limited. Methods: A retrospective single-center analysis was performed including consecutive patients with locally advanced NSCLC treated with perioperative chemo-immunotherapy between March 2024 and March 2026. Patients received platinum-based chemotherapy combined with pembrolizumab or durvalumab, followed by surgical resection with curative intent. Surgical, pathological, and postoperative outcomes were analyzed. Results: Thirty patients received neoadjuvant CHT-IO, of which 25 (83.3%) underwent surgical resection. Reasons for failure to proceed to surgery included treatment-related toxicity or deterioration in performance status (n = 3), disease progression (n = 1), and patient refusal (n = 1). Lobectomy was the most performed procedure (64%), while a minimally invasive approach (uniportal VATS) was adopted in 44% of cases. Moderate-to-severe pleural adhesions (64%) and hilar fibrosis (60%) were observed intraoperatively. Despite these technical challenges, conversion to thoracotomy was required in only one case (4%), no intraoperative complications occurred, and complete (R0) resection was achieved in 96% of patients. Pathological complete response and major pathological response were observed in 36% and 52% of cases, respectively. Postoperative complications occurred in 56% of patients, although most were Clavien–Dindo grade I–II. The presence of comorbidities was the only factor associated with an increased risk of postoperative complications (OR 10.00, 95% CI 0.99–100.46; p = 0.05). Median length of hospital stay was 5.65 ± 2.04 days. One postoperative death due to septic complications was recorded. Conclusions: In this real-world monocentric experience, the combination of perioperative CH-ICIs and surgical resection (including mini-invasive approach) was safe and feasible in patients with locally advanced NSCLC. High rates of complete (R0) resection and encouraging pathological responses were observed, consistent with outcomes reported in randomized trials. Although surgery was overall frequently technically demanding, these changes did not appear to compromise perioperative safety or oncological radicality, even when minimally invasive approaches were adopted. Larger studies with longer follow-up are needed to better define long-term oncological outcomes. Full article

Most UAV missions currently require visiting multiple checkpoints to perform field tasks in environments with varying levels of obstacle complexity. These missions become more challenging because UAVs have limited onboard resources, particularly in terms of energy, making it necessary to determine a safe and efficient path that enables all required visits to be completed while minimizing both travel distance and energy consumption. To address these challenges, this study proposes a hybrid fuzzy metaheuristic approach that integrates Cuckoo Search and Tabu Search for multi-objective UAV path planning. The proposed approach generates collision-free paths in environments with static obstacles and employs fuzzy logic to construct a unified evaluation function, in which distance and energy values are mapped to membership functions and combined into a single fitness score to guide the optimization process. Cuckoo Search drives global exploration of the solution space, while Tabu Search refines solutions locally. Together, they improve path quality and avoid premature convergence. Experimental results across two scenarios with varying obstacle densities and checkpoint counts demonstrate the efficacy of the proposed hybrid approach. Compared with two baseline algorithms, the hybrid approach achieves reductions in path length ranging from 0.01% to 42.11% and in energy consumption ranging from 0.08% to 27.91%, depending on scenario complexity. Moreover, it maintains a high success rate of 96–100% as both checkpoint counts and obstacle density increase, whereas the baseline algorithms drop to 3–13% in more complex environments. These results highlight the effectiveness and scalability of the approach for multi-checkpoint UAV path planning in obstacle-rich environments. Full article

Historically, in the initial stages of solid rocket motor (SRM) development, performance parameters, such as specific impulse, total impulse, mass, and thrust, have been prioritized, with cost considerations often treated as secondary. Consequently, SRM performance optimization under cost constraints has emerged as a central objective in aerospace propulsion. To address this gap, this study establishes a cost–performance evaluation model for SRMs. A Kriging surrogate model, the Non-dominated Sorting Genetic Algorithm II (NSGA-II), and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) are leveraged to minimize the manufacturing cost and maximize the terminal velocity of SRM engines, subject to constraints associated with the maximum operating pressure of the combustion chamber and burn time. First, a cost–performance calculation model for an SRM is developed and validated. Subsequently, Pearson correlation analysis and Sobol-based global sensitivity analysis are combined to reduce the dimensionality of the design parameters, and optimal Latin hypercube sampling is used to generate the training samples. Building on this foundation, a Kriging surrogate model is constructed. The cost–performance model of the SRM is subjected to multi-objective optimization using NSGA-II and TOPSIS to support decision-making. The results indicate that the proposed cost–performance calculation model achieves an error below 5%, demonstrating high accuracy. Among the design parameters, the combustion chamber length, nozzle outlet area, and expansion ratio significantly influence the cost and performance of SRMs. The surrogate models exhibit strong predictive accuracy, with coefficients of determination exceeding 0.9. The optimized TOPSIS scheme yields a performance improvement of 10.94% with a cost increase of 4.15% compared with the reference scheme. In summary, the cost–performance evaluation and optimization framework established in this work provides quantitative decision support for SRM design under cost constraints, and the integrated methodology can be extended to other aerospace propulsion systems or complex engineering equipment. This contributes to achieving synergistic optimization of performance and cost under resource limitations, and offers practical guidance for advancing affordability-driven design in propulsion engineering. Full article