This article presents a mathematical model designed to simulate the impact of targeted interventions aimed at preventing HIV transmission among female sex workers (FSWs) and their clients, while also analyzing their effects on the health of the general population. The compartmental model distinguishes between high-risk populations (FSWs and their clients) and low-risk populations (sexually active men and women in the general population), and links prevention efforts in high-risk groups to the evolution of the epidemic in the low-risk population. The fundamental properties of the model, such as the positivity of solutions and the boundedness of the system, have been verified, and the basic reproduction number R₀ has been calculated. Finally, the stability of the model was studied using Varga’s theorem and the Lyapunov method. Simulation results show that targeted prevention among FSWs and their clients reduces HIV incidence in the general population. This framework provides a valuable tool for guiding policymakers in the design of effective strategies to combat the epidemic, especially relevant in the context of suspension of USAID funding.

The characterization of rock mass along the tunnel alignment based on physical, geological and geotechnical data of the project area was used in this work. The support systems were recommended for all geotechnical units using RMR and tunneling quality index (Q-system) support chart. The paper also consists in making a two-dimensional numerical study of the stability of the left lateral slope of the Portal of the tunnel with the Slide 6.0 software and inside provisional support with the Phase.2 2D program. The study shows good results of the internal rock mass stability of the tunnel and satisfactory safety factor (FoS) in terms of collapse analyzes of the lateral slope of the tunnel portals.

Three novel coordination polymers {[Cu₂(bitbu-OMe)₄(SO₄)₂]·6MeOH}_n (1), {[Co₂(bitbu-OMe)₄(NCS)₄]_0.5·2DMF}_n (2), {[Co(bitbu-OMe)₂(NCS)₂]·2MeOH}_n (3) (bitbu-OMe = 1,1’-[(5-tert-butyl-2-methoxybenzene-1,3-diyl)dimethanediyl]bis(1H-imidazole)) are synthesized through a slow evaporation method using solvothermal technique of CuSO₄·5H₂O or Co(SCN)₂ with bitbu-OMe. X-ray diffraction analysis results reveal that 1, 2, and 3 have similar two-dimensional layer networks. The study of the effect of the methoxy group in bitbu-OMe towards the stability of ligand conformation in obtained coordination polymers becomes necessary to be conducted in the future to unveil the reason for conformation similarity of ligand in coordination polymers.

Objective: The effects of muscle fatigue appear to elicit a transient means of postural instability; however, the recovery of postural stability after fatiguing exercise has not been extensively studied. This study aimed to determine the immediate effect of local vibration applied to fatigued plantar flexor muscles on postural stability in healthy young adults. Design: True Experimental (pre-test - post test design with a control group). Setting: A tertiary care centre. Participations: 42 healthy young adults. Intervention: Fatigue of plantar flexors muscles was induced by repeated dynamic contractions performed to maximum exhaustion. Experimental group (n= 21) received local vibration to fatigued muscles with a handheld vibrator whereas the control group (n = 21) received no intervention (rest). Postural stability was assessed using one leg stance test (OLST) under three different conditions viz. pre-fatigue, post-fatigue and post rest/vibration. Results: Comparative analysis of postural stability within the group was done pre-fatigue, post-fatigue and post rest/vibration condition using Kruskal-Wallis test. A significant decrease from pre-fatigue to post-fatigue condition (p-value < 0.001); and a significant increase from post-fatigue to post rest/vibration condition (p-value < 0.001) was observed in OLST in both - control group and experimental group. However, further comparison of OLST between the groups (using unpaired t test) showed a significant difference in post-fatigue condition versus post rest/vibration condition in favour of the experimental group. Conclusion: Plantar flexors fatigue significantly affects one leg stance time in healthy young adults. Results of this study show that there is an immediate effect of vibration to fatigued muscles on recovery of postural stability in healthy young adults. Recovery of postural stability achieved quickly with such a simple tool may help increase the degree of participation in sports and other similar activities which can cause muscles to fatigue. However, more studies are required to determine this effect using other clinical measures.

This study proposes an integrated approach combining geographic information systems (GIS) and geotechnical analyses to assess the stability of the Oued Ayda mountain lake dam, located in the Siliana Governorate, northwestern Tunisia. The mechanical properties of the embankment and foundation materials were integrated into a Mohr-Coulomb geomechanical model, while the pore water pressure distribution was simulated for various representative hydromechanical scenarios: end of construction, normal operation, rapid drainage, and short- and long-term empty reservoir conditions. The stability analysis, performed using the Morgenstern-Price method with the SLOPE/W software (GeoStudio), reveals high safety factors on the upstream side (SF > 3 in the short term and SF ≥ 2 in the long term), indicating good resistance of this slope to hydraulic and mechanical stresses. Conversely, the results show that the downstream slope exhibits significantly lower safety factors, ranging from 1.335 to 1.338 under long-term conditions, particularly during normal operating and rapid drainage scenarios. These reduced values indicate a high vulnerability of this slope to persistent saturation and adverse hydraulic gradients. In conclusion, although the dam exhibits satisfactory overall stability, the downstream slope remains the most vulnerable area of the structure. The results underscore the need for rigorous management of water level fluctuations and suggest reinforcing the drainage system or implementing targeted stabilization measures to ensure the long-term safety and durability of the structure.

Background: The sacroiliac joint (SIJ) plays a crucial role in transmitting axial loads and maintaining pelvic stability. Sacroiliac joint arthropathy (SIJA) accounts for 10%–30% of low back pain cases but remains underrecognized due to overlapping pain referral patterns and nonspecific imaging findings. Diagnosis relies primarily on characteristic pain distribution and provocative maneuvers, with image-guided intra-articular block serving as the diagnostic gold standard. This study aimed to characterize the clinical profile of block-confirmed SIJA, emphasizing referral pain distribution, triggering position, and provocative test responses. Methods: A cross-sectional study was conducted on 98 patients with diagnostic block–confirmed SIJA at Siloam Hospital Lippo Village, Indonesia. Demographic data, referral pain sites, sitting duration, and results of FABER, compression, and distraction tests were analyzed descriptively. Results: The mean age was 52.07 ± 14.17 years, with 72.4% females. Referral pain most frequently involved the lower back (28.6%) and thigh (28.6%), with occasional extension to the groin (8.2%) or calf (4.1%). Over half of patients (55.1%) reported sitting more than six hours daily. Pain was predominantly triggered during sit-to-stand transitions (85.7%) and while sitting (74.5%). SIJ tenderness (98.0%) and FABER positivity (75.5%) were most consistent. Conclusion: The dominant referral pain in SIJA involves the lower back and posterior thigh. Sit-to-stand transition is the most frequent triggering position, while FABER testing demonstrates the highest diagnostic yield among provocative maneuvers. These consistent patterns may serve as practical clinical indicators to improve diagnostic accuracy in suspected SIJ-related pain.

In this paper, we will examine a rather complex case of the paradoxical nature of certain conclusions that may arise when studying the numerical convergence of a specific nonlinear recursive sequence, known in the literature as Muller’s sequence. To analyze the peculiar computational behavior of this sequence, it is necessary to employ a powerful mathematical framework in order to understand the nontrivial issues that can arise when the software implementation of this seemingly simple mathematical problem. These challenges often stem from the limitations of numerical methods and the inherent errors in computer arithmetic, which can affect the accuracy and stability of the results, particularly when dealing with iterative methods like Muller's sequence.

This systematic review aimed to evaluate the biomechanical properties, functional performance, and clinical outcomes of different hip prosthesis materials and designs used in total hip arthroplasty (THA). A comprehensive search strategy identified 34 peer-reviewed studies published between 2015 and 2024. The materials investigated included cobalt-chromium-molybdenum (CoCrMo), titanium alloys, PEEK, ceramics, and advanced surface coatings such as polycrystalline diamond (PCD). In addition, dual mobility systems, lattice structures, and additively manufactured and patient-specific implants were assessed. The studies utilized clinical trials, finite element analysis, and biomechanical testing to compare outcomes such as wear resistance, stress distribution, osseointegration, and range of motion. The findings demonstrated that titanium alloys and porous lattice structures reduce stress shielding, while ceramics and CoCrMo provide superior wear resistance. Dual mobility implants improved joint stability and range of motion, particularly in high-risk patients. PEEK and PCD showed promising properties but lacked robust long-term data. The integration of advanced manufacturing technologies and material innovations has led to more personalized and biomechanically efficient solutions for THA. Further longitudinal studies are needed to validate these developments. This review provides a critical synthesis of the biomechanical, functional, and clinical implications of contemporary hip prosthetic systems.

Background: Educational attainment is often regarded as a pathway to economic stability and social mobility. However, the Minorities’ Diminished Returns (MDRs) framework has demonstrated that the effects of educational attainment on various economic, behavioral, and health outcomes are weaker for marginalized populations, including racial/ethnic minorities, immigrants, LGBTQ+ individuals, and those living in disadvantaged areas. While MDRs have been documented for various marginalized demographic groups, the role of trauma in moderating socioeconomic outcomes remains underexplored. Objective: This study examines whether lifetime trauma exposure diminishes the positive association between educational attainment and poverty-to-income ratio (PIR), a key indicator of economic well-being. Methods: Using data from the National Survey of American Life (NSAL), we analyzed a nationally representative sample of 6,008 adults, including Black, White, Latino, and Other racial/ethnic groups. We employed linear regression models to evaluate the association between the independent variable educational attainment and the outcome PIR. We then tested lifetime trauma as a moderator of this association. Models controlled for age, gender, employment, and race/ethnicity. Results: Educational attainment was positively associated with PIR across all groups, but the strength of this association was significantly attenuated for individuals with a history of lifetime trauma. These effects were independent of covariates. Conclusions: These findings extend the MDRs framework by highlighting trauma as a potential contributor to diminished returns of education on socioeconomic wellbeing. Structural inequities that increase trauma exposure in minoritized populations may also limit the economic benefits of education, particularly for groups with multiple trauma exposures. Policies aimed at addressing economic inequality must integrate social policies that reduce trauma and stress.