Directory of Open Access Journals

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    The Subtle evolution of pulmonary parenchymal changes: A case of lady windermere syndrome emerging from chronic MAC infection in an immunocompetent patient with scoliosis

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    Mycobacterium avium complex, a commonly seen infection in individuals with a compromised immune system, can also affect people who are immunocompetent. One particularly important manifestation is in elderly females with a competent immune system, involving the middle lobe and lingula lobe of the lung. This is known as Lady Windermere syndrome (LWS). An 84-year-old female patient with certain nonpulmonary comorbidities initially got a diagnosis of MAC infection but refused to undergo any medication therapy, she presents after 5 years for a follow up visit and is found to have significant changes in her pulmonary parenchyma on investigation findings, concerning for this syndrome. LWS is a rather uncommon condition, rarely presents in clinical settings and described very less often in the literature. This report is aimed at increasing awareness of LWS as a possible diagnosis that should be considered in patients with a chronic MAC infection and a specific pattern of parenchymal changes discussed in this report in detail

    Associations of polycyclic aromatic hydrocarbons exposure with mortality and effect modification by folate biomarkers in a prospective population

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    The associations of folate biomarkers and polycyclic aromatic hydrocarbons (PAHs) in the general population remain unclear. Therefore, this study aimed to examine whether folate biomarkers are associated with PAHs, and whether folate biomarkers can mitigate adverse health outcome caused by PAHs. This prospective cohort study included 11,246 participants from the National Health and Nutrition Examination Survey (NHANES), which documented 1,303 deaths over a mean follow-up of 9.1 years. Multivariable linear regression models were used to examine the relationship between urinary individual PAHs and folate biomarkers. Multivariable Cox proportional hazards regression models were used to calculate hazard ratios and 95 % CIs for the associations of PAHs and folate biomarkers with CVDs mortality and all-cause mortality. We found negative associations between folate in red blood cells (RBC) and urinary 1-Hydroxyphenanthrene (percentage change for a 2·7 fold-increase in folate −4.19 %, 95 % CI -5.80 % to −2.56 %CI), 2-Hydroxyfluorene (−6.66 %, −7.84 % to −5.49 %), 3-Hydroxyfluorene (−5.78 %, −6.77 % to −4.78 %)) and 1-Hydroxynapthalene (−2.75 %, −3.48 % to −2.01 %). The associations between serum folate and PAHs were consistent with those observed for RBC folate, and negative associations were also found between serum folate and 2-Hydroxynapthalene (−4.10 %, −5.26 % to −2.94 %). Within the lowest quartile of folate levels in RBC, there are strong associations of 2-Hydroxyfluorene, 3-Hydroxyfluorene, 1-Hydroxynapthalene, and 2-Hydroxynapthalene with elevated risk of CVDs mortality [HRs (95 % CI) >1]. As folate levels in RBC increase to the third and fourth quartiles, these associations no longer exist [HRs (95 % CI) <1, P-interaction<0.05]. The positive associations between urinary PAHs and CVDs mortality are also eliminated as serum folate levels rise [HRs (95 % CI) <1, P-interaction<0.05]. Furthermore, we also found higher levels of folate in both RBC and serum can greatly reduce the adverse impact of 1-Hydroxynapthalene on all-cause mortality. Consistent results were also validated in daily dietary folate and the folic acid supplement intake. Our study highlighted a robust negative relationship between urinary PAHs and folate. Additionally, folate was found to effectively mitigate mortality caused by PAHs, although we did not observe a direct reduction in mortality attributable to folate

    Surface texture effects on mechanical properties of additively manufactured polylactic acid

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    Additive manufacturing is favored for its capacity to create intricate geometries and enhance component functionality more efficiently than traditional methods. Applying texture to materials is one of the processes used to add functionality to products, wherein it can improve adhesion and tribological behavior in biomedical applications while also controlling mechanical properties and providing perceptual and aesthetic improvements. In this study, custom black-white images containing vertical lines were prepared and added as textures to the design of tensile test specimens during slicing. Custom textured and untextured tensile test specimens were fabricated using the Fused Deposition Method with polylactic Acid filament to evaluate the effect of texture parameters, such as protrusion offset (0.25, 0.50, 0.75 mm), number of protrusions (3, 6) and infill pattern (rectilinear, line, concentric), on the tensile strength of the specimens. Through the analysis of tensile test results and examination of microscopic and slicing software images, it was found that texturing resulted in a reduction in ultimate tensile strength due to nozzle trajectory deviations and stress concentration. The least detrimental texturing parameters observed in this study were 0.5 mm protrusion offset and 3 protrusions with concentric and line infill patterns, resulting in a reduction in tensile strength of 2.36 and 5.79%, respectively when compared to untextured specimens

    Finite Element Analysis of Mechanical Ocular Sequelae from Badminton Shuttlecock Projectile Impact

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    Purpose: With the growing popularity of badminton worldwide, the incidence of badminton-related ocular injuries is expected to rise. The high velocity of shuttlecocks renders ocular traumas particularly devastating, especially with the possibility of permanent vision loss. This study investigated the mechanism behind ocular complications through simulation analyses of mechanical stresses and pressures upon shuttlecock impact. Design: Computational simulation study. Participants: None. Methods: A 3-dimensional human eye model was reconstructed based on the physiological and biomechanical properties of various ocular tissues. Finite element analysis simulations involved a frontal collision with a shuttlecock projectile at 128.7 km/hour (80 mph). Intraocular pressure (IOP) changes and tissue stress were mapped and quantified in the following ocular structures: the limbus, ciliary body, zonular fibers, ora serrata, retina, and optic nerve head. Main Outcome Measures: Intraocular pressure and tissue stress. Results: Upon shuttlecock impact, compressive force was transferred to the anterior pole of the cornea, propagating posteriorly to the optic nerve head. Deflection of forces anteriorly contributed to refractory oscillations of compressive and tensile stress of ocular tissue. Initial impact led to a momentary (<1 ms) spike in IOP 5.66 MPa (42.5 × 103 mmHg) that radially distributed for a very brief instance (<1 ms) of pressure at the trabecular meshwork of the iridocorneal angle of 1.25 MPa (9.4 × 103 mmHg). The lens had a maximal posterior displacement of 1.5 mm with peak zonular fiber tensile strain of 52%. The limbus, ciliary body, and ora serrata had a peak tensile stress of 5.16 MPa, 1.90 MPa, and 0.62 MPa, respectively. Compressive force from the sclera concentrated at the optic nerve head for a peak stress of 5.97 MPa while peak pressure from vitreous humor was 7.99 MPa. Conclusions: Shuttlecock impact led to a very brief, substantial rise in pressure and stress significant for tissue damage and subsequent complications, such as secondary glaucoma, angle recession, lens subluxation, hyphema, or retinal dialysis. Our findings offer valuable mechanistic insights into how ocular structures are affected by shuttlecock projectile impact to inform clinical assessments and treatment strategies, while highlighting the importance of protective eyewear in racket sports. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article

    Does peers' credit behavior affect smallholder farmers’ credit and savings decisions? Evidence from the northern region of Ghana

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    Access to credit remains a major challenge in developing countries, leading to increased poverty levels and low savings. Despite the importance of social networks and social support systems, the literature has not considered the link between peer credit on one hand and own credit and savings on the other. This paper examines the effect of peer credit on farmers (own) credit and savings using cross-sectional data from 400 farm households in northern Ghana. The study employed a spatial Durbin model (SDM) and the control function approach to identify the network effects. The results show that an increase in the share of farmers’ peers with credit, increases own credit access but leads to a decline in savings. This implies the presence of endogenous effects on credit, but no evidence of contextual effects was found. The results further show some heterogeneities in the effect of peer credit but with diminishing marginal returns to own credit. The study recommends that to promote credit access, financial institutions must focus on farmers with high-network credit. They should also ensure the sustainability of credit among farmers to improve savings. The study underscores the importance of cohesive networks in promoting credit access among farmers, therefore key stakeholders such as the government, religious and traditional authorities as well as political and civil society organizations must collaborate in their efforts to promote social cohesion by minimizing civil disputes and conflicts. This will ensure that farm households in developing communities continue to benefit from social network support

    A new probabilistic model with properties and Monte Carlo simulation: Its explorations in dance education and music engineering

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    In the examination of real-life situations, the application of probability distributions is often crucial for statistical analysis of the real-life scenarios. Many models based on probability have been utilized in disciplines such as music education, music engineering, and other music-related areas. Hence, acknowledging the significance of probability-based approaches, this article introduces an innovative probability model known as a new generalized Rayleigh distribution. The suggested model is established on merging the generalized Rayleigh distribution with a prominent weighted probabilistic method. The mathematical properties, specifically the quartile-based features of the novel generalized Rayleigh distribution, are investigated. Moreover, we outline the derivation of the point estimators for the unknown parameters of the new model. A thorough simulation study is also conducted to examine the performances of these point estimators. Within the music industry, specifically in music education and music engineering, we examine the practical implications of the new generalized Rayleigh distribution. We observe that it offers a superior fit when contrasted with other distributions. Our findings demonstrate that the new distribution is a inclusion to the group of probability distributions that can be applied in music engineering and other closely connected engineering fields for the statistical analysis of real-life events

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