2,435 research outputs found

    Gaussian Free Field in the background of correlated random clusters, formed by metallic nanoparticles

    Full text link
    The effect of metallic nano-particles (MNPs) on the electrostatic potential of a disordered 2D dielectric media is considered. The disorder in the media is assumed to be white-noise Coulomb impurities with normal distribution. To realize the correlations between the MNPs we have used the Ising model with an artificial temperature TT that controls the number of MNPs as well as their correlations. In the T0T\rightarrow 0 limit, one retrieves the Gaussian free field (GFF), and in the finite temperature the problem is equivalent to a GFF in iso-potential islands. The problem is argued to be equivalent to a scale-invariant random surface with some critical exponents which vary with TT and correspondingly are correlation-dependent. Two type of observables have been considered: local and global quantities. We have observed that the MNPs soften the random potential and reduce its statistical fluctuations. This softening is observed in the local as well as the geometrical quantities. The correlation function of the electrostatic and its total variance are observed to be logarithmic just like the GFF, i.e. the roughness exponent remains zero for all temperatures, whereas the proportionality constants scale with TTcT-T_c. The fractal dimension of iso-potential lines (DfD_f), the exponent of the distribution function of the gyration radius (τr\tau_r), and the loop lengths (τl\tau_l), and also the exponent of the loop Green function xlx_l change in terms of TTcT-T_c in a power-law fashion, with some critical exponents reported in the text. Importantly we have observed that Df(T)Df(Tc)1ξ(T)D_f(T)-D_f(T_c)\sim\frac{1}{\sqrt{\xi(T)}}, in which ξ(T)\xi(T) is the spin correlation length in the Ising model

    Improvement of COD and TOC reactive dyes in textile wastewater by coagulation chemical material

    Get PDF
    This study was designed to investigate the removal of reactive dyes, Samofix Red V-RBL and Samofix Green V-G from wastewater using a two step Al (III) coagulation/activated carbon adsorption method.The effects of pH and coagulant dosage as well as the effects of contact time and a powdered activated carbon dosage on dye removal were studied. The process was optimized with reasonable consumption of coagulant and quantity of obtained sludge. Coagulation as a main treatment process followed by adsorption achieved almost total elimination of both dyes from wastewater with significant reduction (90%) of chemical oxygen demand (COD), total organic carbon (TOC) and absorbable organic halide (AOX). Besides high efficiency of dye removal, the combined treatment process offers many advantages for potential application such as coagulant savings, minimal amount of sludge formationand also an economic feasibility since it does not require high costs for chemicals and equipments

    Anthropometric indices in individuals infected with ascaris lumbericoids in Iran

    Get PDF
    Context: Ascaris Lumbericoids infection is more common in children and teenagers and in areas with poor sanitation or crowded living conditions. Largest of all the parasites inhabiting the human intestine it is also the most common of parasitic infections in developing countries. It has been reported to infect about one-fourth of the world population. Chronic ascariasis has been reported to adversely effect the growth rate and anthropometric indices in infected individuals of growing age. Aims: The goal of this research was to evaluate the anthropometric indices in individuals infected with Ascaris in Hamedan province of Iran. Settings and Design: This was a descriptive cross sectional study. Methods and Material: Six hundred fourteen randomly selected individuals who were inhabitants of Hamedan province of Iran were chosen for this study. Stool samples of these individuals were collected and then experimented with Formel-Ether method to determine Ascaris Lumbericoids infection. Height and weight of these individuals were measured and compared with the indices related to NCHS. Demographic information of these individuals was entered into questionnaires and ultimately was analyzed with SPSS software. Results: Out of the total study population, 16.5% of individuals were found to be infected with Ascaris. Out of the individuals infected with Ascaris, 1% were underweight. In the age groups of 6-10, 11-15, 16-20 years, 3.5%, 5.1% and 3.5% were found to be suffering from malnutrition, respectively. Conclusion: Malabsorption in children might result in malnutrition. In this study, few individuals infected with Ascaris had malnutrition, thus Ascaris infection may not be an important cause of malnutrition among children in our area

    Cost effectiveness analysis of Avonex and CinnoVex in Relapsing Remitting MS

    Get PDF
    INTRODUCTION: Multiple sclerosis is a chronic and degenerative neurological disease characterized by loss of myelin sheath of some neurons in brain and spinal cord. It is associated with high economic burden due to premature deaths and high occurrence of disabilities. The aim of the current study was to determine cost effectiveness of two major products of interferon 1a in patients with relapsing-remitting multiple sclerosis. METHOD AND MATERIALS: Altogether, 140 patients who have consumed Avonex and CinnoVex in Relapsing Remitting MS for at least two years were randomly selected (70 patients in each group). Health-related quality of life (HRQoL) was assessed using the adopted MSQoL-54 instrument. Costs were measured and valued from Ministry of Health and Medical Education (MOHME) perspective. Two-way sensitivity analysis was used to check robustness of the results. RESULTS: Patients in CinnoVex group reported significantly higher scores in both physical (69.5 vs. 50.9, P<0.001) and mental (63.3 vs. 56.6, P=0.03) aspects of HRQoL than Avonex group. On the other hand, annual cost of CinnoVex and Avonex were 2410 US and 4515US per patient, respectively (P<0.001). CONCLUSIONS: The results showed that CinnoVex was dominant option over the study period. It is suggested that results of the current study should be considered in allocating resources to MS treatments in Iran. Of course, our findings should be interpreted with caution duo to short term horizon and lack of HRQoL scores at baseline (before the intervention)
    corecore