Chelyshkov Collocation Method for Solving Three-Dimensional linear Fredholm Integral Equations

The main purpose of this work is to use the Chelyshkov-collocation method for the solution of three- dimensional Fredholm integral equations. The method is based on the approximate solution in terms of Chelyshkov polynomials with unknown coefficients. This method transforms the integral equation to a system of linear algebraic equations by means of collocation points. Finally, numerical results are included to show the validity and applicability of the method and comparisons are made with existing results

Application of Lerch Polynomials to Approximate Solution of Singular Fredholm Integral Equations with Cauchy KernelApplication of Lerch Polynomials to Approximate Solution of Singular Fredholm Integral Equations with Cauchy Kernel

In this paper, we develop an effective method based on Lerch polynomials to provide an approximate solution of various cases of Cauchy type singular integral equations. The method reduces the solution of given singular integral equation to the solution of a matrix equation corresponding to linear system of algebraic equations with unknown Lerch coefficients. Error estimation of the presented method is mentioned. Finally, several examples show the reliability and efficiently of the proposed method

The influence of leptin on Th1/Th2 balance in obese children with asthma

OBJECTIVE: In individuals with asthma, obesity induces the production of leptin and is associated with disease severity. Our objective was to evaluate the levels of serum leptin and their effect on Th1/Th2 balance in obese and non-obese children with asthma, as well as to investigate the association between serum leptin levels and clinical outcomes. METHODS: We evaluated 50 atopic children with physician-diagnosed moderate-to-severe persistent asthma and 20 controls. The children with asthma were divided into two groups, by body mass index percentile: obese (n = 25) and non-obese (n = 25). From all subjects, we collected peripheral blood samples in order to determine the levels of leptin, IFN-γ, and IL-4. Asthma severity was assessed by an asthma symptom score, and the results were correlated with the parameters studied. RESULTS: Serum leptin levels were significantly higher in the obese asthma group than in the non-obese asthma group, as well as being significantly higher in the children with asthma than in the controls, whereas IFN-γ levels were significantly higher and IL-4 levels were significantly lower in the obese asthma group than in the non-obese asthma group. In addition, the obese asthma group showed higher asthma symptom scores and significantly lower FEV1 (% of predicted) than did the non-obese asthma group. There was a significant positive correlation between leptin and IFN-γ levels only in the obese asthma group. CONCLUSIONS: Although leptin is involved in the pathogenesis of asthma in obese and non-obese children, its effect is more pronounced in the former. In the presence of high leptin levels, only obese children with asthma exhibited Th1 polarization, with higher IFN-γ levels and greater asthma severity

Potential Effect of Biochar on Soil Properties, Microbial Activity and <i>Vicia faba</i> Properties Affected by Microplastics Contamination

Microplastics (MPs) contamination is an emerging issue globally; however, adverse impacts of MPs on soil, plants and microbial activity have not been intensively studied. In this study, the potential effect of different levels of MPs (1.5, 7.5, 15%) has been investigated on soil properties, plant properties (Vicia Faba) and microbial activities through a pot experiment. The effect of biochar (BC: 2%) to mitigate the adverse effects of MP has also been examined. Soil properties (pH, EC, OM, CaCO3 and some elements) have significantly differed due to contamination of soil by MPs as well as by adding BC to the soil. The pH and CaCO3 were significantly increased more than in the control, while EC, TDS, available P, Mn and Fe were significantly decreased lower than the control, which implies adsorption on microplastic. Plant properties, such as enzymes, chlorophyll and fresh and dry weight in roots, were adversely affected by MPs contamination; however, BC mitigated this effect, especially with low contamination levels of MPs. The fresh and dry weight of the shoot was not significantly affected by MPs. The cytogenetic analysis showed that the mitotic index was significantly reduced compared to the control (9.39%), while BC increased the mitotic index at 1.5% MPs (7.11%) although it was less than the control. The percentage of abnormalities of V. faba root tip cells under different levels of MPs was significantly increased more than the control; however, BC mitigated this effect, especially at 7.5% MPs. The total count of bacteria and fungi even in soil or in the rhizosphere area did not follow a clear trend; however, the effect of BC was clear in increasing their activities. Microbial biomass carbon and nitrogen were also significantly affected by MPs and BC. In this study, the BC level was low, however, it mitigated some adverse effects of MPs, especially at 1.5 and 7.5% of MPs. Thus, the BC could be promising in mitigating the negative impacts of MPs when applied with suitable levels that need more future studies