10 research outputs found

    Free convection heat transfer and entropy generation in an odd-shaped cavity filled with a Cu-Al2O3 hybrid nanofluid

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    The present paper aims to analyze the thermal convective heat transport and generated irreversibility of water-Cu-Al2O3 hybrid nanosuspension in an odd-shaped cavity. The side walls are adiabatic, and the internal and external borders of the enclosure are isothermally kept at high and low temperatures of Thand Tc, respectively. The control equations based on conservation laws are formulated in dimensionless form and worked out employing the Galerkin finite element technique. The outcomes are demonstrated using streamlines, isothermal lines, heatlines, isolines of Bejan number, as well as the rate of generated entropy and the Nusselt number. Impacts of the Rayleigh number, the hybrid nanoparticles concentration (ϕhnf), the volume fraction of the Cu nanoparticles to ϕhnf ratio (ϕr), width ratio (WR) have been surveyed and discussed. The results show that, for all magnitudes of Rayleigh numbers, increasing nanoparticles concentration intensifies the rate of entropy generation. Moreover, for high Rayleigh numbers, increasing WR enhances the rate of heat transport

    Therapeutic Effects of Laser on Partial Osteotomy in the Rat Model of Hypothyroidism

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    Introduction: Several experimental studies have displayed positive result for laser radiation on stimulating bone regeneration in recent years. The purpose of this experimental study was to determine low-level laser (LLL) effects on partial bone defects in hypothyroidism male rat.Methods: Forty male Wistar rats were randomly distributed as below groups: hypothyroidism + laser (Hypo + laser), hypothyroidism (Hypo), and control. Four weeks after surgery, the tibia bone was removed. Biomechanical and histological examinations were performed immediately.Results: Our results showed significant reduction in the absorption of energy, resistance in bending deformation (bending stiffness), maximum force, high stress load, trabecular bone volume, and number of osteocytes, osteoblasts and osteoclasts in the osteotomy site in hypothyroidism rats compared to hypothyroidism + laser group (P < 0.05).Conclusion: The results indicated that using laser may improve fracture regeneration and it may accelerate bone healing in hypothyroidism rat

    Kawasaki disease in children: a retrospective cross-sectional study

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    Introduction Kawasaki disease (KD) is a systemic vasculitis, seen mostly in children. Epidemiology of KD is dependent on geographical location and seasonality. Although many years have passed since the first report of KD, multiple related factors are still unknown. Material and methods We investigated the clinical, paraclinical, and therapeutic aspects of KD in Kerman, Iran by performing a retrospective, descriptive, cross-sectional study on all children hospitalized due to KD between 2007 and 2020. Results A total of 340 patients with mean ±SD age of 29.83 ±22.55 months participated in the study. Most of our patients were two to five years old. The male : female ratio was ~ 1.4 : 1. A few of our patients had a family history of KD or vasculitis (0.3%, 1.7%). Typical KD was more common by a large margin (316 patients with typical KD). More than half of our patients had a duration of hospitalization of under ten days. All of our patients were febrile. Hand/foot and lip/mouth changes were the second and third most common clinical findings in more than 60% of our patients. Other manifestations were conjunctivitis in 40%, skin rashes in 34.8%, gastrointestinal manifestations in 33.9%, and lymphadenopathy in 25.3%. Echocardiography revealed abnormalities in 78.6% of the participants; coronary artery aneurysm (CAA) was the most frequent (22.5%) and follow-up echocardiography revealed that all of them regressed within 6 months after treatment. The two laboratory tests with the highest ratio of abnormality were erythrocyte sedimentation rate (95%) and hemoglobin (83.3%). C-reactive protein and liver function tests were also abnormal in most patients. All of our patients received intravenous immunoglobulin and acetylsalicylic acid. Conclusions Kawasaki disease must be considered in every febrile child, especially those with risk factors, because timely diagnosis and treatment are essential to prevent complications. Health policies should focus on appropriate diagnosis and treatment to prevent the occurrence of sequelae

    External validation and recalibration of an incidental meningioma prognostic model - IMPACT: protocol for an international multicentre retrospective cohort study

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    Introduction: Due to the increased use of CT and MRI, the prevalence of incidental findings on brain scans is increasing. Meningioma, the most common primary brain tumour, is a frequently encountered incidental finding, with an estimated prevalence of 3/1000. The management of incidental meningioma varies widely with active clinical-radiological monitoring being the most accepted method by clinicians. Duration of monitoring and time intervals for assessment, however, are not well defined. To this end, we have recently developed a statistical model of progression risk based on single-centre retrospective data. The model Incidental Meningioma: Prognostic Analysis Using Patient Comorbidity and MRI Tests (IMPACT) employs baseline clinical and imaging features to categorise the patient with an incidental meningioma into one of three risk groups: low, medium and high risk with a proposed active monitoring strategy based on the risk and temporal trajectory of progression, accounting for actuarial life expectancy. The primary aim of this study is to assess the external validity of this model. Methods and analysis: IMPACT is a retrospective multicentre study which will aim to include 1500 patients with an incidental intracranial meningioma, powered to detect a 10% progression risk. Adult patients ≥16 years diagnosed with an incidental meningioma between 1 January 2009 and 31 December 2010 will be included. Clinical and radiological data will be collected longitudinally until the patient reaches one of the study endpoints: intervention (surgery, stereotactic radiosurgery or fractionated radiotherapy), mortality or last date of follow-up. Data will be uploaded to an online Research Electronic Data Capture database with no unique identifiers. External validity of IMPACT will be tested using established statistical methods. Ethics and dissemination: Local institutional approval at each participating centre will be required. Results of the study will be reported through peer-reviewed articles and conferences and disseminated to participating centres, patients and the public using social media
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