Search Results (457)

The structural design of rail vehicle bodies significantly influences rail vehicle performance, passenger comfort, and operational efficiency. This study presents a comparative analysis of three key concepts of a rail vehicle body, namely a differential, an integral, and a hybrid structure, with a focus on their structural principles, material utilization, and implications for manufacturability and maintenance. Three rail vehicle body variants were developed, each incorporating a low-floor configuration to enhance accessibility and interior layout flexibility. The research explores the suitable placement of technical components such as a power unit and an air-conditioning system, and it evaluates interior layouts aimed at maximizing both passenger capacity and their travelling comfort. Key features, including door and window technologies, thermal comfort solutions, and seating arrangements, are also analyzed. The study emphasizes the importance of compromises between structural stiffness, reparability, production complexity, and passenger-oriented design considerations. A part of the research includes a proposal of three variants of a rail vehicle body frame, together with their strength analysis by means of the finite element method. These analyses identified that the maximal permissible stresses for the individual versions of the frame were not exceeded. Findings contribute to the development of more efficient, accessible, and sustainable regional passenger rail vehicles. Full article

Background/Objectives: Urinary incontinence (UI), defined as the involuntary loss of urine, is common among female athletes. As more women engage in competitive sports, numerous studies have explored UI in young, nulliparous, and physically active women. The objectives of this study were (i) to analyze the prevalence, severity, and characteristics of UI in professional nulliparous female soccer players and (ii) to compare the status of the pelvic floor muscles (PFMs) between professional soccer players and physically active young women. Methods: This descriptive cross-sectional study included professional soccer players (n = 18) and physically active women (n = 14). UI was assessed using the ICIQ-SF questionnaire, and PFM function was evaluated through intracavitary examination using the PERFECT method. Additional data were collected on body composition and on urinary, bowel, and sexual health. Results: UI affected 35.7% of physically active women and 50% of professional soccer players. Stress urinary incontinence (SUI) was the most common type, present in 100% of affected soccer players and 60% of affected active women. The severity of UI was mostly mild, with no significant differences between groups. PFM assessment revealed deficiencies in control, relaxation, endurance, and rapid contractions, as well as difficulties performing an effective perineal locking (PL) maneuver during increased intra-abdominal pressure. Conclusions: These findings highlight the need for targeted programs focused on strengthening and educating athletes about their PFMs, aiming to prevent UI and improve both performance and quality of life. The study reinforces the importance of preventive strategies for pelvic floor health in sports. Full article

This study defines evidence-based minimum internal floor areas required to support long-term residential use across different household types. It addresses the following question: what is the smallest viable floor area that supports sustained occupancy without persistent stress, conflict, or turnover? An integrative review method was employed, drawing from behavioural studies in environmental psychology, international regulatory standards, and real-world market data. The analysis focuses on essential domestic functions including sleep, hygiene, food preparation, storage, social interaction, and work. Quantitative findings from tenancy surveys, post-occupancy research, and market performance data indicate that residential units below 30 square metres for single occupants and 45 square metres for couples are consistently associated with reduced satisfaction and shorter tenancies. Regulatory minimums across diverse jurisdictions tend to converge near these same thresholds. The study proposes technical minimums of 30, 45, and 60 square metres for one-, two-, and three-person households, respectively. These values reflect functional lower bounds rather than ideal or aspirational sizes and are intended to inform performance-based housing standards. Full article

Addressing the stability control challenges of roadways with composite roofs in the No. 34 coal seam of Donghai Mine under high-strength mining conditions, this study employed integrated methodologies including laboratory experiments, numerical modeling, and field trials. It investigated the mechanical response characteristics of the composite roof and developed a synergistic control system, validated through industrial application. Key findings indicate significant differences in mechanical behavior and failure mechanisms between individual rock specimens and composite rock masses. A theoretical “elastic-plastic-fractured” zoning model for the composite roof was established based on the theory of surrounding rock deterioration, elucidating the mechanical mechanism where the cohesive strength of hard rock governs the load-bearing capacity of the outer shell, while the cohesive strength of soft rock controls plastic flow. The influence of in situ stress and support resistance on the evolution of the surrounding rock zone radii was quantitatively determined. The FLAC^3D strain-softening model accurately simulated the post-peak behavior of the surrounding rock. Analysis demonstrated specific inherent patterns in the magnitude, ratio, and orientation of principal stresses within the composite roof under mining influence. A high differential stress zone (σ₁/σ₃ = 6–7) formed within 20 m of the working face, accompanied by a deflection of the maximum principal stress direction by 53, triggering the expansion of a butterfly-shaped plastic zone. Based on these insights, we proposed and implemented a synergistic control system integrating high-pressure grouting, pre-stressed cables, and energy-absorbing bolts. Field tests demonstrated significant improvements: roof-to-floor convergence reduced by 48.4%, rib-to-rib convergence decreased by 39.3%, microseismic events declined by 61%, and the self-stabilization period of the surrounding rock shortened by 11%. Consequently, this research establishes a holistic “theoretical modeling-evolution diagnosis-synergistic control” solution chain, providing a validated theoretical foundation and engineering paradigm for composite roof support design. Full article

This paper introduces a new conceptual framework for interpreting urethral retro-resistance pressure (URP) as a dynamic, intra-procedural tool—ΔURP—for evaluating external urethral sphincter (EUS) engagement during injection therapy. With renewed interest in therapies that directly target the EUS, there is a critical need for real-time functional feedback at the site of action. This conceptual review re-examines URP in the context of emerging EUS-targeted treatments—such as bulking agents, regenerative injections, and neuromodulatory interventions—and proposes a dynamic model (ΔURP) to measure changes in sphincteric resistance as a functional biomarker during intervention. We review the anatomical, neurophysiological, and histological features of the EUS complex; trace the clinical rise and decline of URP; and compare its utility to conventional diagnostic tools. ΔURP, defined as the change in URP from baseline, is explored as an objective measure of EUS function. We outline its potential applications in guiding therapy, evaluating response, and standardizing outcomes across treatments. Conventional urodynamic measures fail to isolate distal sphincter function. In contrast, URP directly challenges the EUS and, when combined with imaging or procedural tools, may provide real-time feedback on sphincter engagement. When reframed as a dynamic, motion-based readout, URP may fill a critical gap in procedural urology—offering a physiologic signal of therapeutic engagement during EUS-targeted interventions. ΔURP has the potential to revive and repurpose a once-abandoned method into a clinically actionable biomarker for next-generation continence care. Full article

Urinary incontinence is characterized by the involuntary leakage of urine. The primary cause of stress urinary incontinence in women is the weakening of the pelvic floor muscles. Stress urinary incontinence (SUI) is a significant global health problem that impacts mainly middle-aged women, with a severe impact on their quality of life. Traditional diagnostic methods and treatments often fail, although technological innovations have improved diagnostic accuracy, such as specific questionnaires or transperineal ultrasound. While medical therapies and surgical procedures are continuously being developed, controversies about the correct choices regarding diagnostic and treatment methods continue to exist. The aim of our review was to identify the innovative diagnostic tools and effective treatment procedures for SUI. A narrative review was conducted due to the heterogeneity of the studies. New methods for diagnosis and treatment have gained ground, and we have covered them in our review; however, the field continues to expand. A personalized approach to diagnosis is also a requirement because of the limitations of conventional urodynamic studies, and we emphasize the importance of such personalization in enhancing clinical decision making. Future medical strategies that combine both preventive and therapeutic care are desirable. Newer technologies were brought to light in this review, including stem cell therapy and laser therapy. Full article

In the Karaganda coal basin, deteriorating geomechanical conditions have been observed, including seam disturbances, diminished strength of argillite–aleurolite strata, water ingress, and pronounced floor heave, all of which markedly increase the labor intensity of maintaining developmental headings. The maintenance and operation of these entries for a reference coal yield of 1000 t necessitate 72–75 man-shifts, of which 90–95% are expended on mitigating ground pressure effects and restoring support integrity. Conventional heave control measures—such as relief drifts, slotting, drainage, secondary blasting, and the application of concrete or rock–bolt systems—deliver either transient efficacy or incur prohibitive labor and material expenditures while lacking unified methodologies for predictive forecasting and support parameter design. This study therefore advocates for an integrated framework that synergizes geomechanical characterization, deformation prognosis, and the tailored selection of reinforcement schemes (incorporating both sidewall and floor-anchoring systems with directed preloading), calibrated to seam depth, geometry, and lithological properties. Employing deformation state assessments to optimize reinforcement layouts for floor stabilization in coal mine workings is projected to curtail repair volumes by 30–40% whilst significantly enhancing operational safety, efficiency, and the punctuality of face preparation. Full article

To elucidate evolutionary characteristics of the surrounding rock failure mechanism in a double-roadway layout, this work is grounded on in the research context of the Jinjitan Coal Mine, focusing on the deformation and failure mechanisms of double roadways. This paper addresses the issue of resource wastage resulting from the excessive dimensions of coal pillars in prior periods by employing a research methodology that integrates theoretical analysis, numerical simulation, and field monitoring to systematically examine the movement characteristics of overlying rock in the working face. On that basis, the size of coal pillar is optimized. The advance’s stress transfer law and deformation distribution characteristics of the return air roadway and transport roadway are studied. The cause of the asymmetric deformation of roadway retention is explained. A differentiated design is conducted on the support parameters of double-roadway bolts and cables under strong dynamic pressure conditions. The study indicates that a 16 m coal pillar results in an 8 m elastic zone at its center, balancing stability with optimal resource extraction. In the basic top-sloping double-block conjugate masonry beam structure, the differing stress levels between the top working face’s transport roadway and the lower working face’s return air roadway are primarily due to the varied placements of key blocks. In the return air roadway, floor heave deformation is managed using locking anchor rods, while roof subsidence is controlled with a constant group of large deformation anchor cables. The displacement of surrounding rock increases under the influence of both leading and lagging pressures from the previous working face, although the change is minimal. There is a significant correlation between roadway deformation and support parameters and coal pillar size. With a 16 m coal pillar, differential support of the double roadway lowers the return air roadway deformation by 30%, which improves the mining rate and effectively controls the deformation of the roadway. Full article

Background: Stress urinary incontinence (SUI) is frequently underrecognized in late pregnancy, with limited tools for effective risk assessment. This study aimed to evaluate the predictive value of clinical and pelvic floor ultrasound parameters for SUI and construct a validated risk model. Methods: Clinical, obstetric, and pelvic floor ultrasound findings were collected from a total of 521 women in late pregnancy who were enrolled in the study. Based on follow-up results, participants were categorized into SUI and non-SUI groups. Logistic regression analyses were used to identify independent risk factors for SUI, which were incorporated into a nomogram. Results: Four independent predictors were identified: vaginal delivery history (odds ratio [OR] = 2.320), bladder neck funneling (OR = 2.349), bladder neck descent (OR = 1.891), and pubococcygeus muscle contraction strain rate (OR < 0.001). The nomogram achieved an AUC of 0.817 (95% CI: 0.770–0.863) in the training set and 0.761 (95% CI: 0.677–0.845) in the test set. Conclusions: The nomogram based on clinical and pelvic floor ultrasound parameters accurately predicts the risk of SUI during late pregnancy, offering a useful tool for early identification and personalized management. Full article

A narrow coal pillar in double-roadway excavation can solve the problem of working face connection and improve the resource recovery rate, but narrow coal pillars are affected by the full mining stress. Taking the 2109 double-roadway excavation of Qingwa Coal Mine as the engineering background, the roof mechanical structure model of a narrow coal pillar in a double-roadway excavation layout was established, and the bearing characteristics of different coal pillar widths under the influence of full dynamic pressure were studied. The narrow coal pillar retention width was obtained and tested through field industrial experiments. The main research results were as follows: (1) The relationship between the coal pillar bearing load and the immediate roof length was deduced, and the bearing stress of the coal pillar was divided into the steep decline stage, the transition stage, and the stabilization stage. The coal pillar within the width of the stabilization stage has a certain strength surplus capacity. (2) Under the influence of full dynamic pressure, the 5~7 m coal pillar yielded to failure, and the coal pillar of 8 m and above had a certain residual bearing capacity, compared with the first mining. After the second mining, the elastic zone in the coal pillar of each width was significantly reduced; there was no elastic grid in the coal pillar of 5 m and 6 m in width, and the grid area and proportion of the elastic zone of the coal pillars with widths of 7 m and above were very low. The optimal retention width of the narrow coal pillar was determined to be 8 m. (3) Under the influence of repeated mining, the impact of first mining on the roadway displacement of the roof and floor plate was greater, followed by the solid coal side, which had less impact on the coal pillar side. The secondary mining had a greater impact on the floor, followed by the coal pillar side and the solid coal side, which had little impact on the roadway roof. This paper also provides a significant reference for the retention of narrow coal pillars in double-roadway excavation. Full article

When deep-buried tunnels are excavated using the drill-and-blast method, the surrounding rock is subjected to combined cyclic blasting loads and excavation-induced stress unloading. Understanding the distribution characteristics of rock damage zones under these conditions is crucial for the design and safety of building-integrated underground structures. This study investigates the relationship between surrounding rock damage and in situ stress conditions through numerical simulation methods. A constitutive model suitable for simulating rock mass damage was developed and implemented in the LS-DYNA (version R12) code via a user-defined material model, with parameters determined using the Hoek–Brown failure criterion. A finite element model was established to analyze surrounding rock damage under cyclic blasting loads, and the model was validated using field data. Simulations were then carried out to explore the evolution of the damage zone under various stress conditions. The results show that with increasing hydrostatic pressure, the extent of the damage zone first decreases and then increases, with blasting-induced damage dominating under lower pressure and unloading-induced shear failure prevailing at higher pressure. When the hydrostatic pressure is less than 20 MPa, the surrounding rock stabilizes at a distance greater than 12.6 m from the tunnel face, whereas at hydrostatic pressures of 30 MPa and 40 MPa, this distance increases to 29.4 m. When the lateral pressure coefficient is low, tensile failure occurs mainly at the vault and floor, while shear failure dominates at the arch waist. As the lateral pressure coefficient increases, the failure mode at the vault shifts from tensile to shear. Additionally, when the horizontal stress perpendicular to the tunnel axis (σ_H) is less than the vertical stress (σ_v), variations in the axial horizontal stress (σ_h) have a significant effect on shear failure. Conversely, when σ_H exceeds σ_v, changes in σ_h have little impact on the extent of rock damage. Full article

Phase-separated membraneless biomolecular condensates in the cytoplasm and nucleus are now recognized to play a major role in modulating diverse functions in mammalian cells, and contribute to cancer pathogenesis through dysregulated function of condensates of transcription factors such as STAT3 and fusion oncoproteins. Oral cancer, the sixth most prevalent malignancy worldwide, in the absence of overt causes such as tobacco or alcohol, most frequently occurs in a U-shaped zone (floor of mouth, side of tongue, anterior fauces and retromolar region) reflecting the path of liquid transit through the mouth. The cellular basis for this “high-risk” zone and the biochemical mechanisms used by oral cells to combat repetitive tonicity and temperature stresses are incompletely understood. We had previously observed that at 37 °C, in OECM1 oral carcinoma cells, cytoplasmic condensates of antiviral human GFP-MxA GTPase disassembled within 1–2 min of exposure of cells to saliva-like one-third hypotonicity, and underwent “spontaneous” reassembly in the next 5–7 min. Moreover, hypotonic beverages (water, tea, coffee), investigated at 37 °C, triggered this condensate cycling. In the present studies we investigated whether this process was temperature sensitive, representative of cold vs. warm drinks. We observed a slowing of this cycle at 5 °C, and speeding up at 50 °C. The involvement in this disassembly/reassembly process of WNK-SPAK/OSR1 serine-threonine kinase pathway, best studied for regulation of water and Na, K and Cl influx and efflux in kidney tubule cells, was evaluated by us in oral cells using pathway inhibitors WNK463, WNK-IN-11 and closantel. The pan-WNK inhibitor WNK463 inhibited hypotonicity-driven condensate disassembly, while the SPAK/OSR1 inhibitor closantel markedly slowed reassembly. Unexpectedly, the WNK1-selective inhibitor (WNK-IN-11), triggered a dramatic and rapid (within 1 h) spheroid to fibril transition of GFP-MxA condensates in live cells, but without affecting MxA antiviral function. The new data suggest a novel hypothesis for the anatomic localization of oral cancer in the U-shaped “high-risk” zone in the mouth: dysfunction of biomolecular condensates in oral cells along the beverage transit pathway through the mouth due to repetitive tonicity and temperature stresses that might underlie a prooncogenic progression. Full article

This study focuses on how rocks respond mechanically and how to keep them stable when soft rock roadways are under deep tectonic stress. It does this through a combination of theoretical analysis, numerical simulations, and field applications. We created a mechanical model of roof strata to calculate how much they would bend under both horizontal tectonic stress and their weight. This modeling helped us determine the critical yield limits. A systematic study of the angle θ between the direction of tectonic stress and the axis of the roadway showed that the concentration of horizontal stress on the roof gets stronger as θ increases, while the vertical stress on the sidewalls slowly gets weaker. The main sign of surrounding rock failure is shear damage that is most severe at the roof, floor, and shoulder angles. The maximum plastic zone depth occurs at θ = 90°. Studies that looked at both gob-side and along-roadway stages found that the two types of failure were very different, characterized by severe roof damage during roadway advancement and pronounced coal pillar instability in gob-side conditions. Based on these results, targeted support strategies were successfully used in field engineering to control deformations and provide both theoretical foundations and practical solutions for stabilizing deep soft rock roadways under tectonic stress. Full article

Bacterial chondronecrosis with osteomyelitis (BCO) is a major cause of lameness in broiler chickens. This condition arises when bacteria from the gastrointestinal or aerosol tract migrate to infect bone microfractures, often exacerbated by rapid growth, reduced blood flow, and mechanical stress. As concerns about antibiotic resistance grow, probiotics have gained attention for their potential to improve gut health and reduce systemic bacterial load. This study evaluated the efficacy of a probiotic program comprising an Enterococcus faecium-based spray (2 × 10⁹ CFU/bird at hatch) and a triple-strain Bacillus-based feed additive (B. subtilis 597, B. subtilis 600, and B. amyloliquefaciens 516 at 500 g/t feed from day 1 to 56), applied individually or in combination. A wire-flooring challenge model was used to simulate BCO transmission. A total of 1560 Cobb 500 broilers were randomly assigned to five groups: T1 (positive control), T2 (negative control), T3 (E. faecium spray only), T4 (Bacillus feed supplement only), and T5 (combined treatment). Lameness was evaluated daily from day 21 to 56 through clinical observation and necropsy. The challenge model was validated with >70% lameness in T1. All probiotic treatments significantly reduced lameness compared to T2 (p < 0.05): 35.4% in T3, 36.7% in T4, and 47.6% in T5. The combined treatment resulted in the statistically highest reduction in lameness incidence, indicating a synergistic rather than merely additive effect compared to individual treatments. These findings support the use of targeted probiotic strategies to reduce BCO lameness and enhance skeletal health and welfare in broilers. Full article

The number of people suffering from urinary incontinence increases every year. Along this trend, the knowledge of society increases regarding the various methods available for treating this ailment. Both patients and researchers are constantly looking for new treatments for urinary incontinence. One of the new solutions is sonofeedback of the pelvic floor muscles, which may help to strengthen them and thus reduce the problem. The aim of this study was to evaluate the effectiveness of sonofeedback and transvaginal electrostimulation in increasing the bioelectrical activity of pelvic floor muscles in postmenopausal women with stress urinary incontinence. Sixty women with stress urinary incontinence were enrolled in the study. The patients were divided into two groups: A, where sonofeedback was used, and B, where electrostimulation of the pelvic floor muscles was performed with biofeedback training. In patients, the resting bioelectrical activity of the pelvic floor muscles was assessed using an electromyograph. The assessment of the resting bioelectrical activity of the pelvic floor muscles was performed before the therapy, after the 5th training, and after the therapy. It was observed that after the end of the therapy, the average bioelectrical potential increased by 1.1 µV compared with the baseline in group A. It can be suggested that the sonofeedback method is comparatively effective in reducing symptoms that are associated with urinary incontinence as an electrostimulation method with biofeedback training. Full article