Effect of Central Bank Independence on Political Business Cycles in Iran: An Application of Smooth Transition Autoregressive Regression

The main purpose of this article is to investigate the effect of central bank independence on the establishment of Political Business Cycles (PBC) in Iran. For this purpose, the modified model of Shi and Svensson (2006) in the framework of the Smooth Transition Autoregressive Regression (STAR) during the period of 1978-2018 has been used. The results, in addition to confirming the linear relationship between the variables, showed that in the election period, for the values ​​of PBC (ratio of budget deficit to GDP) above the threshold, central bank independence, a positive and significant effect, and for values ​​below threshold has had a significant negative effect on PBC. Another finding of this paper is that the sum of the coefficients of central bank independence in the two regimes indicates the negative effect of increasing central bank independence on PBC. Therefore, it is suggested that, in addition to restricting the use of oil revenues, increasing the central bank's independence in the true sense of the word should be considered in order to gradually reduce PBC

An Investigation of the Effective Factors on Foreign Direct Investment with Emphasis on the Optimal Tax Rate in Selected Countries (Spatial Durbin Model for Panel Data)

Foreign investment is the function of globalization in the economies. There are so important factors for absorbing it . Cheap and skilled labor, the degree of openness of the economy and policies, activities and actions that attract this type of capitals are most important factors. To achieve this goal, governments enter a competitive game and try to attract these investments with their policies. In this study, first using a dynamic optimization control model and developing a Ramsey model to determine the optimal taxation on foreign direct investment in a small open economy for Iran and selected countries and then investigate the effective factors on Foreign direct investment with emphasis on the role of taxes through spatial econometric method (spatial Durbin model) for panel data during the years 2000 to 2017. The results show that the optimal tax rate for attracting foreign investment for the countries under study is close to zero. The results of spatial estimation by Dhaver sine and Euclidean methods also confirm the spatial dependence of the variables affecting foreign direct investment

The Effect of Urbanization on Energy Consumption in Iranian Provinces: Spatial Panel Data Approach

Energy is one of the essential inputs in production that due to inefficient and inappropriate use of its resources, its consumption has increased significantly. In this regard, the identification of factors affecting energy consumption in the provinces is important. This study aims to investigate the effect of urbanization on energy consumption in Iranian provinces. To do so, we used the STIRPAT model to design the econometric model. The spatial error econometric model in panel data was used to estimate the effect of urbanization on energy consumption in 28 Iranian provinces from 2002 to 2015. The results show that the relationship between urbanization and energy consumption is inverted U-shaped. This finding indicates that an increase in urbanization first causes to increase and then decreases energy consumption

Investigating the Impact of International Sanctions on Performance Indicators of Tehran Stock Exchange with Industries Divided From 2010 to 2020

In this research, the impact of the impact of the international sanctions index on the performance indices of the Tehran Stock Exchange by industries, including mass production indices, banks, insurance, automobiles, investments, basic metals, rubber, cement, chemical, industry, petroleum products, pharmaceuticals, transportation, sugar And thanks, we have checked for the time period from 2010 to 2020. For this purpose, we have used the weekly data of the above variables and using the Multivariate Generalized Autoregressive Conditional Heteroskedasticity (MGARCH),   Dynamic Conditional Correlation Generalized Autoregressive Conditional Heteroskedasticity (DCC-GARCH) model. Based on the results of the research, the influence of the sanctions index with different intervals (1 to 29) on the performance indicators of Tehran Stock Exchange with different ARCH and GARCH intervals (1 to 20) was proved by obtaining significant coefficients of -0.098417 to 0.137398

A Pictorial Key for Culex pipiens Complex (Diptera: Culicidae) In Iran

Background: The aim of this study was to design pictorial key and taxonomic literature of Culex pipiens complex in Iran. Methods: Larvae were collected using standard dipping methods in 13 randomly selected areas of Bushehr, Hame­dan, Kerman, Khorasan-e-Razavi, Khuzistan, Mazandaran, Tehran, Sistan and Baluchistan and Yazd Provinces from April 2009 to October 2010. The data were analyzed using SPSS Ver. 11.5. Results: Culex pipiens larvae were identified based on the Seta 1 of the abdominal segments III–IV in north and central parts of Iran. This diagnostic character had some variation among the Cx. quinquefasciatus collected from south of the country. The identification value of intersection of costa, subcosta and bifurcation of R2+3 of female veins, was calculated as 90–100 % for Cx. pipiens. This diagnostic character was varied among the Cx. quinquefas­ciatus specimens. The male genitalia found as the main characters to distinguish of Cx. quinquefasciatus from Cx. pipiens. Conclusion: It is necessary more studies on the behavior and genetic variations of Cx. pipiens complex in Iran

Antioxidant activity and protecting health effects of common medicinal plants

Medicinal plants are traditionally used in folk medicine as natural healing remedies with therapeutic effects such as prevention of cardiovascular diseases, inflammation disorders, or reducing the risk of cancer. In addition, pharmacological industry utilizes medicinal plants due to the presence of active chemical substances as agents for drug synthesis. They are valuable also for food and cosmetic industry as additives, due to their preservative effects because of the presence of antioxidants and antimicrobial constituents. To commonly used medicinal plants with antioxidant activity known worldwide belong plants from several families, especially Lamiaceae (rosemary, sage, oregano, marjoram, basil, thyme, mints, balm), Apiaceae (cumin, fennel, caraway), and Zingiberaceae (turmeric, ginger). The antioxidant properties of medicinal plants depend on the plant, its variety, environmental conditions, climatic and seasonal variations, geographical regions of growth, degree of ripeness, growing practices, and many other factors such as postharvest treatment and processing. In addition, composition and concentration of present antioxidants, such as phenolic compounds, are related to antioxidant effect. For appropriate determination of antioxidant capacity, the extraction technique, its conditions, solvent used, and particular assay methodology are important