441 research outputs found

    Analysis of transient radiative heat transfer using high bounded scheme of the FTn finite volume method

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    Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.In this work, the transient behavior of the absorbing, emitting, and isotropically scattering medium in radiative equilibrium is examined, using the FTn Finite Volume Method (FTnFVM), in terms of temporal and spatial evolutions of the incident radiation, radiative heat flux, and temperature of the medium. Commonly used convection schemes in computational fluid dynamics (CFD) such as STEP and CLAM are introduced for spatial discetization of the transient radiative transfer equation (TRTE). Also a non-uniform (FTn) angular scheme is used to capture the physics of the radiative wave propagation. The present approach is then validated by comparing with published data and applied to problems of three-dimensional isotropically participating media. It is shown that the FTn FVM reduces largely the ray effects. Also, the false scattering is largely remedied using the CLAM scheme is applied for the angular discretization. In all computations, the CLAM scheme produces more accurate results (with coarse grid) than the step scheme. Using the same (relatively coarse) spatial grid, the CLAM scheme captures the steep gradients and penetration depths more accurately than the step scheme. Then, effects of the scattering albedo and the optical thickness on the incident radiation distributions are presented and discussed.cf201

    Neonatal adrenal hemorrhage presenting as acute scrotum

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    Neonatal adrenal hemorrhage may rarely present as acute scrotum,  mimicking the conditions that require an immediate operative intervention. The authors report one such case and discuss the importance of clinical examination and ultrasonography to avoid an unnecessary surgical  exploration.Keywords: neonatal acute scrotum, neonatal adrenal hemorrhage, scrotal  hematoma, testicular torsio

    Morphological aspects and pathological impacts of cystic echinococcosis in liver of slaughtered sheep and host-parasite relationship

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    ABSTRACT Cystic echinococcosis (CE) is a parasite-borne disease caused by the larval stage of Echinococcus granulosus belonging to family Taeniidae, is an endemic disease, distributed worldwide as a neglected parasite with socioeconomic repercussions. It causes severe alterations in liver of infected host, and it could be fatal if untreated. The main objective of the present study is to measure and evaluate the condition of hydatidosis in slaughtered sheep in Al Baha region, Saudi Arabia. A total of 601 slaughtered sheep in Al Baha abattoirs were examined for hydatidosis during the year 2020. Various organs were examined for the presence of parasite cysts, and the cyst contents were examined by light microscopy. Also, liver sections infected with cysts were examined for pathological alterations and host-parasite interactions. Forty-two animals were infected (6.09%) with the highest prevalence during summer. During gross examination, it was observed that the sheep liver is the most affected organ by the disease. The liver contained multiple cysts with varying sizes, filled with clear to slightly turbid fluid containing protoscoleces. Detailed sections of the infected liver revealed significant fibrosis around the central vein, portal vein congestion, infiltration of inflammatory cells, and necrosis. Sections through hydatid cysts showed the presence of three surrounding layers with a laminar membrane bordering the cyst lined by a germinal epithelium surrounding several brood capsules with many protoscolesces inside supported by a set of rostellar hooklets. Considerable efforts should be spent to control the transmission of parasitic cysts and inhibit the incorrect disposal of infected meat from slaughterhouses. Also, more focus should be done on epidemiological and control programs of these parasites

    Modelling and experimental results of a biomass pyrolysis pilot plant

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    Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.Fire Dynamics Simulator (FDS) and global modelling are used to solve numerically pyrolysis, combustion and heat recuperation in a pilot plant of biomass pyrolysis using pyrolysis products as fuel. Obtained results are validated with experimental measurements. In the case of FDS modelling three different treatments of radiation are considered: without radiation, with gray gas radiation and with non gray gas radiation. The results of numerical simulations are compared with the global model results and with the experimental results. It was shown that the FDS results are in good qualitative and quantitative agreement with the experimental results. The global model gives qualitative results in agreement with experimental results with less CPU time compared with FDS results. Whereas FDS results are more accurate than those of the global model. At the end of the process FDS results are better than global model results this is due to the fact that global model doesn’t take into account the thermal inertia of the pilot plant. The global model is used to study the racing reaction in the pilot plant and to study the case with and without catalyser. FDS is used to predict CO and CO2 emissions. The effect of the non gray gas behaviour is emphasised and demonstrated to affect pollutant emissions.cf201

    Ameliorating effect of olive oil on fertility of male rats fed on genetically modified soya bean

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    Background: Genetically modified soya bean (GMSB) is a commercialized food. It has been shown to have adverse effects on fertility in animal trials. Extra virgin olive oil (EVOO) has many beneficial effects including anti-oxidant properties. The aim of this study is to elucidate if addition of EVOO ameliorates the adverse effects on reproductive organs of rats fed on GMSB containing diet. Methods: Forty adult male albino rats (150–180 g) of Sprague Dawley strain were separated into four groups of 10 rats each: Group 1 – control group fed on basal ration, Group 2 – fed on basal ration mixed with EVOO (30%), Group 3 – fed on basal ration mixed with GMSB (15%), and Group 4 – fed on basal ration mixed with GMSB (15%) and EVOO (30%). This feeding regimen was administered for 65 days. Blood samples were collected to analyze serum zinc, vitamin E, and testosterone levels. Histopathological and weight changes in sex organs were evaluated. Results: GMSB diet reduced weight of testis (0.66±0.06 vs. 1.7±0.06, p<0.001), epididymis (0.489±0.03 vs. 0.7±0.03, p<0.001), prostate (0.04±0.009 vs. 0.68±0.04, p<0.001), and seminal vesicles (0.057±0.01 vs. 0.8±0.04, p<0.001). GMSB diet adversely affected sperm count (406±7.1 vs. 610±7.8, p<0.001), motility (p<0.001), and abnormality (p<0.001). GMSB diet also reduced serum zinc (p<0.05), vitamin E (p<0.05), and testosterone (p<0.05) concentrations. EVOO diet had no detrimental effect. Addition of EVOO to GMSB diet increased the serum zinc (p<0.05), vitamin E (p<0.05), and testosterone (p<0.05) levels and also restored the weights of testis (1.35±0.16 vs. 0.66±0.06, p<0.01), epididymis (0.614±0.13 vs. 0.489±0.03, p<0.001), prostate (0.291±0.09 vs. 0.04±0.009, p<0.001), seminal vesicle (0.516±0.18 vs. 0.057±0.01, p<0.001) along with sperm count (516±3.1 vs. 406±7.1, p<0.01), motility (p<0.01), and abnormality (p<0.05). Conclusion: EVOO ameliorates the adverse effects of GMSB on reproductive organs in adult male albino rats. This protective action of EVOO justifies its use against the oxidative damage induced by GMSB in reproductive organs

    Characteristics of the fission fragments induced by the 129Xe + natSn reactions at E = 8–15A MeV

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    The study of nuclear multifragmentation is important for understanding the reaction mechanisms in heavy-ion collisions. In the present work, we study the nuclear reaction 129Xe + natSn in the energy range E = 8 to 15 AMeV. This experiment was performed at GANIL with the multidetector INDRA. We study the charge distributions produced in this reaction, which are broad and cover a large atomic number range. By using the data of this experiment, we identify four channels differing by the number of fragments: 1, 2, 3 and 4 fragments. In this contribution we will show a method to reconstruct the average size and excitation energy of the primary fission fragments, before their decay. The method employed is based on the fragment-light charged particles relative velocity correlation functions. Preliminary results will be presented

    Inhaled Nitric Oxide for Clinical Management of COVID-19: A Systematic Review and Meta-Analysis

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    Background: Severe COVID-19 is associated with hypoxemia and acute respiratory distress syndrome (ARDS), which may predispose multiorgan failure and death. Inhaled nitric oxide (iNO) is a clinical vasodilator used in the management of acute respiratory distress syndrome (ARDS). This study evaluated the response rate to iNO in patients with COVID-19-ARDS. Method: We searched Medline and Embase databases in May 2022, and data on the use of iNO in the treatment of ARDS in COVID-19 patients were synthesized from studies that satisfied predefined inclusion criteria. A systematic synthesis of data was performed followed by meta-analysis. We performed the funnel plot and leave-one-out sensitivity test on the included studies to assess publication bias and possible exaggerated effect size. We compared the effect size of the studies from the Unites States with those from other countries and performed meta-regression to assess the effect of age, year of publication, and concomitant vasodilator use on the effect size. Results: A total of 17 studies (including 712 COVID-19 patients) were included in this systematic review of which 8 studies (involving 265 COVID-19 patients) were subjected to meta-analysis. The overall response rate was 66% (95% CI, 47–84%) with significantly high between-studies heterogeneity (I2 = 94%, p < 0.001). The funnel plot showed publication bias, although the sensitivity test using leave-one-out analysis showed that removing any of the study does not remove the significance of the result. The response rate was higher in the Unites States, and meta-regression showed that age, year of publication, and use of concomitant vasodilators did not influence the response rate to iNO. Conclusion: iNO therapy is valuable in the treatment of hypoxemia in COVID-19 patients and may improve systemic oxygenation in patients with COVID-19-ARDS. Future studies should investigate the mechanism of the activity of iNO in COVID-19 patients to provide insight into the unexplored potential of iNO in general ARDS

    Prevalence of overweight and obesity based on the body mass index; a cross-sectional study in Alkharj, Saudi Arabia

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    Background: Obesity and overweight are accompanied with several different chronic diseases. Overweight and obesity can be measured by using body mass index (BMI) and is also used widely as an index of relative adiposity among any population. The aim of the study is to evaluate the prevalence of overweight and obesity among general population in Al-Kharj, Saudi Arabia.Methods: Cross-sectional analysis was undertaken from a representative sample (N = 1019) of the Al Kharj population. Anthropometric measurements including the waist circumference (in centimeters), height (in meters), and weight (in kilograms) of the subjects were undertaken by means of standard apparatus. SPSS 24.0 was utilized for statistical analysis of the data.Results: Majority of respondents in this study were overweight and obese (54.3%) compared with 45.7% being non-obese. A linear positive association of increasing BMI with older age groups was present in males and females. Men had larger waist circumference, weight and height measures as compared with their female counterparts. Regression analysis showed increasing age, being married and high serum cholesterol to be the significant predictors of overweight and obesity while gender, education level, job status, and having diabetes were not.Conclusions: The obesity-overweight prevalence in the Saudi population is high mainly across both genders. However, the associated factors are potentially preventable and modifiable. The regional barriers to lifestyle modifications and interventions to encourage active lifestyles, especially among adolescents to limit the occurrence of obesity and ultimately promote health and wellbeing, are warranted. Furthermore, prospective studies are needed in future to confirm the aetiological nature of such associations

    Prevalence of prediabetes, diabetes and Its predictors among females in alkharj, saudi arabia: A cross-sectional study.

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    BACKGROUND/OBJECTIVE: The prevalence of prediabetes and diabetes is reaching epidemic proportions across the globe. Therefore, this study aims to determine the prevalence of prediabetes and diabetes, together with its accompanying risk factors, among young females. METHODS: An exploratory cross-sectional survey was conducted with 638 Saudi females in Alkharj, Saudi Arabia. Statistical analysis was carried out using STATA version 14. Odds ratios for the risk of diabetes and associated factors were calculated using log-binomial and multinomial logistic regression. Standardized prevalence and strata-specific prevalence of diabetes and prediabetes for different risk factors were also calculated. FINDINGS: The study revealed that nondiabetics and prediabetics were more prevalent between the ages of 18 and 24 years, while diabetic patients were consistently between 25 to 44 years of age. The average value for HbA1c in females was 5.44. Regression analysis shows that being older, married, obese, a smoker or less educated significantly increases the risk for both prediabetes and diabetes. Mutivariable analysis revealed obesity had a significant association with both prediabetes and diabetes. Prediabetics were 2.35 times more likely to be obese as compared to nondiabetics, with 95% CI (1.38-3.99). Similarly, diabetics were 6.67 times more likely to be obese compared to nondiabetics 95% CI (1.68-26.42). CONCLUSION: Our study shows the prevalence of diabetes and prediabetes among females from Al Kharj was 3.8% and 18.8%, respectively. The diabetic and prediabetic female participants had higher mean BMI and waist circumference, were older in age, were married, and smoked as compared to nondiabetics. In the context of the findings of our study, and keeping in view the the burden of this disease globally and in our population, it has now become extremely important to understand these factors and encourage health-promoting behaviors to construct effective interventions
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