مهراب نصیری

One of the main concerns of investors is the Stock price crash risk in the market and research in this field may be so important for the Capital. Increasing stock price crash risk makes investors pessimistic about investing in the securities exchange and this may cause them to go out of the capital market. This research studied the effect of the firm’s operation and the future risk of price fall of the equities in the firms accepted by the securities exchange of Tehran between 2012-2016. The sample includes 500 observation. The independent variables consist of rate of the return of the assets, ratio of market value to office value of the firm and Toobin’s Q index and the profit of each equity and the depended value is the future stock price crash risk. The findings suggested that there is negative significant relation between the firm’s operation (the rate of return of the assets, the ratio of the market value to office value of the firm, the Toobin’s Q index and the profit of each equity) and future stock price crash risk in the firms accepted by the securities exchange of Tehran. In other words we can anticipate the future mutation or stock price crash risk with looking at the firm’s operation and take action to buy or sell that firm’s equities.

The goal of this research is for the role of adjusting the corporate governance and connection between the absence of the earnings management and dividend policy in accepted policies Tehran stock market .because of this, the information of 100 accepted companies in the following organization and Tehran stock market between 1391 and 1395 has been studied. To do this dividend policy has been used as dependent indignant absence of earnings management as independent indignant, and corporate governance as modulatory indignant; this index consists of three criteria of independence of the board of directors, auditor independence and institutional ownership. moreover, usual squares have been used to know the answers of inquiries. The results show that there are of the board has a negative and significant effect and the independence of the auditor has a positive and significant impact on the relationship between dividend policy and earnings management. But institutional ownership has no significant effect on the relationship between dividend policy and profit management.

The main purpose of this study, is surveying the factors that affect Price Impact of block Trades in the stock market. For this reason, the sample consisted of 525 block trades have been selected randomly of accepted companies in Tehran Stock Exchange, that have block trade during the period 1390 to 1392. In this paper, total, temporary and permanent price impact is used as dependent variables, and the size of block trade, stock price volatility, trading turnover, market return, momentum and Bid-Ask Spread are used as explanatory variables. The results show that the relationship between turn over, Market return and Bid-Ask Spread with three dependent variable (total, temporary and permanent price impact) are significant. Also the relationship between size of block trade with total, permanent price impact, the relationship between Volatility of stock price with total, temporary price impact and, the relationship between momentum with temporary price impact are significant.

The main purpose of this study, is surveying the asymmetry of price impact of block trades in buying and selling. For this reason, the sample consisted of 525 block trades (310 block in buying and 215 block in selling)have been selected randomly of companies that have block trade during the period 1390 to 1392. This trades have attracted the attention of shareholders because of low limits, high volume and price effects. Shareholders do block trades to identify, assess and improve liquidity and market capacity. In this study, first block trades divided into two group’s in buying and selling with using the midpoint method, then the hypotheses are tested. According to previous studies, cross-sectional regression results indicate that there is asymmetry between price impact of block trades in buying and selling.

The relationship between earning management and bid-ask spread of stock, and also the relationship of trading volume in corporations with noninstitutional ownership during the years 2008 to 2012 were studied in this paper. The research samples include 48 corporations, in which the noninstitutional ownership stand at a high level. Unlike the recent researches, the new indicator for measuring the earning management has been used in this study. This study was descriptive and correlation and assumptions of multiple regression panel data were analyzed. The results show that there is a positive and significant relationship between earning management and bid-ask spread of stock. The bid-ask spread of stock is considered as liquidity criterion of stock and there is an inverse relationship between this criterion and the liquidity of stock. Thus, there is a negative and significant relationship between earning management and stock liquidity. Besides, the results indicate that there is also a negative and significant relationship between earning management and trading volume. Generally, there is an inverse relationship between stock market liquidity and the earning management of the corporations with high non-institutional ownership.

Introduction &

Visceral Leishmaniasis (kala-azar) is the most important endemic disease in Northwestern Iran, particularly in Ardabil province. This study aimed to review the seroepidemiological studies which have been performed in Ardabil province during 1986-2009.

In this descriptive analytical study, studies which have been carried out from 1986 through 2009 in Northwestern Iran about clinical, diagnostic and epidemiological features of Kala azar, using DAT, were reviewed. Collected data were analyzed using the SPSS software.

in total, 2703 of human visceral leishmaniasis were detected by direct agglutination test (DAT) in Ardabil province, 1787 (66.1%) of them were from Meshkin-shahr district, 837 (31%) cases were from Moghan district, and 79 (2.9%) cases were from Ardabil district. Ninety eight percent of the cases were under 10 years old while only 0.5% of the VL cases were ≥20 years old and 17% of them were under 1 year of age.

Currently Kala-Azar is the most important endemic disease in Northwestern Iran, particularly in Ardabil province. Anti-Leishmania antibodies at the titers of ≥1:3200 using DAT along with clinical signs including fever, anemia and hepatosplenomegaly are considered as active visceral leishmaniasis. DAT antibody titer of 1/800 and lower and absent of clinical signs is considered as negative VL.