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Showing 3 results for Abaszadeh
Prevalence of Campylobacter spp. and their Common Serotypes in 330 Cases of Red-meat, Chicken-meat and Egg-shell in Zanjan City, Iran

Volume 2, Issue 1 (1-2016)
Abstract
Background: Campylobacter spp. are the common pathogens that infect human beings via food. These bacteria are vibrio and have been implicated in abortion. Serotyping is the best way for typing with Penner scheme. C. jejuni and C. coli have 65 serotypes. C. coli is common in birds and dogs. Due to high rate of prevalence of Campylobacter in red-meat, chicken-meat and egg-shell, a suitable method to detect their prevalence, the most common species and serotyping group was necessary. This article describes the prevalence of Campylobacter infection, common serotyping group in 330 samples of red- meat, hen-meat and egg-shell. Materials and Methods: With three methods: enrichment, selective Preston and Skirrow and filtration with membrane filters Campylobacter swere incubated. Bacterial species were identified with physiological and biochemical tests. Penner serotyping was defined with reference antiserum Ag-O and direct agglutination. Results: Prevalence of Campylobacter infection was 21(23%) in red meat, 33(27.5%) in hen meat and 38(31.6%) in eggshell. In egg-shell samples: C. jejuni 20, C. coli 14, C. lari 3 and C. concisus 1 case. In meat common Penner serotyping for C. jejuni O2 had the highest rate. In hen, common Penner serotyping: for C. jejuni O3 and in egg-shell for O1, O2 and O3 had the highest rate. Conclusion: Most infection of campylobacter was found in egg-shell; most common species in these three samples were C. jejuni, then C. coli and C. lari. No C. consicus was found in meat but it was found in hen and egg-shells. In common Penner serotyping for C. jejuni O2 and O3 were the most common and for C. coli in meat O49 and in hen and eggshell O5 were the highest.
Lubrication enhancement in deep drawing process by utilizing nanoparticle additives
Behrooz Zareh-Dsari, Mohammad Abaszadeh, Behnam Davoodi,
Volume 15, Issue 1 (3-2015)
Abstract
Lubrication is an essential factor in sheet metal forming processes such as deep drawing in order to reduce friction at contact surfaces, forming load, tool wear rate and increasing of sheet formability. Various metal oxide nanoparticles can be used as additives to create desirable tribological properties in base lubricants because of their unique properties such as specific surface area. In the present study, the conventional lubricant enhanced by alumina nanoparticles (Al2O3) is utilized in deep drawing process in order to improve frictional conditions. The forming load, surface roughness (Ra) and thickness distribution values of the formed cups were assessed to evaluate the performance of the enhanced conventional lubricant with alumina nanoparticles (Al2O3) in comparison to the conventional lubricant and dry forming condition. The obtained results from experimental tests revealed that adding 0.5 wt.% Al2O3 nanoparticles to the conventional lubricant improves lubrication property significantly and reduces forming load by 16.39% and surface roughness by 19.33% compared to the conventional lubricant. Furthermore, it is observed that using lubricant containing nanoparticle additives results in 23.94% improvement in maximum thickness reduction in critical zone.
A comparative study of the intervention in foreign exchange markets in Iran, Mexico and Türkiye

Volume 24, Issue 1 (spring 2024)
Abstract
The aim of this study is the comparative study of the intervention in foreign exchange markets in Iran, Türkiye and Mexico. Therefore, the goals, methods, and different tactics of the foreign exchange interventions of the central banks are discussed. In addition, in this study, to investigate and compare the behavior of the monetary authorities in the face of increasing exchange rate fluctuations, using the ordinary least squares method, the reaction function of the central bank has been estimated. The results of this research show that the foreign exchange interventions in Iran are different from those of Türkiye and Mexico in terms of the key features investigated. Also, according to the reaction function estimation results, in these countries the increase in the exchange rate leads to more sensitivity of the monetary authorities compared to its decrease.
Introduction
In this research, by examining the features of foreign exchange interventions, the differences and similarities of this foreign exchange policy are evaluated in Iran, Türkiye, and Mexico. Due to features such as the establishment of a floating currency system, the availability of daily intervention data, and the experience of currency crises, two emerging economies, Mexico and Türkiye, have been chosen to match the characteristics of foreign exchange interventions with interventions in Iran.
Methodology
First, we examine the general policies and laws of central banks in relation to foreign exchange policies in Türkiye and Iran. Then we have compared Iran, Mexico, and Türkiye's measures related to foreign exchange interventions. Laws, characteristics, reasons, and laws of foreign exchange interventions in Türkiye, Mexico and Iran are evaluated. The results of this research show how the laws, goals, and implementation methods of different foreign exchange interventions in Türkiye, Mexico, and Iran will reflect different reactions of the monetary authority. In this research, the ordinary least squares method is used to estimate the reaction function of the central banks of Iran, Mexico, and Türkiye. We consider the reaction function of the central bank as follows:
Rt=c+αet~+β(et~)2+vt
In this equation, Rt   is changes in foreign reserves of the central bank and et~  is the nominal exchange rate. Both variables are used with seasonal frequency and also in the form of logarithmic difference.
Findings
The interventions of Mexico and Türkiye are different from the foreign exchange interventions in Iran in terms of the level of transparency, regularity, sterilization, and the tools used. In addition, some goals affecting the interventions were also different in the three countries. This result shows that among the monetary authorities of all three countries, there is a fear of an increase in the exchange rate, and the foreign exchange interventions of the countries are mainly aimed at reducing the exchange rate.
Discussion and Conclusion
The results show that the interventions of Mexico and Türkiye are different from the foreign exchange interventions in Iran in terms of the level of transparency, regularity, sterilization and the tools used. In addition, some goals affecting the interventions were also different in the three countries. Also, the results show that the monetary authorities of all three countries are more sensitive to an increase in the exchange rate than to a decrease in the exchange rate.
 

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