The aim of this study is to assess the characteristics of hot and cold IPO markets in Tehran Stock Exchange. To examin the hypotheses, logit regression and multiple linear regression are used. The sample of the study consists of 118 TSE’s listed companies which have been offered initially during 2001-2013. The results reveal that there is no meaningful relation between hot issue and underpricing. The findings indicate a reverse relation between hot issue and market performance before IPO and a direct relation between RISK of IPOs and hot issue. The results exhibit, although the hot issue phenomenon is not related to underpricing, a lead-lag relation between underpricing and hot issue can be understood and it shows a relation between high initial return and the future IPO volume. Additionally, the study concludes that companies which are offered in hot markets, are more RISKy and underperformance. Moreover, the cross sectional variance in long run abnormal returns is lower for firms going public in hot market. Finally, the findings of the study are sensitive toward the definition of hot issue.

Introduction: This article examines the reasons as well as the shift from low RISK drugs to high RISK drugs. Target in this research consist of people who were low RISK consumers in the past but now they are high RISK consumers. The theoretical framework for this research includes: social strain theory, anomie theory, differential association, social control, model adaptation, social conflict, and social capital theory.Method: This study is a questionnaire survey and data was collected by Statistical methods including the multiple regression analysis, chi-square.Finding: Results of present research have shown that we can see the shift from low RISK drugs such as opium and opium juice to high RISK drugs such as Kerak, Heroine, Crystal and the shift of usage toward injection between addicted people (the prison of Bojnord and Samen clinic of Bojnord.Discussion: This study shows the reasons such as social pressure, low correlation; the way of treatment between addicted person and the rest of the family, cultural poverty, polluted social area, lack of pureness of drugs, and weakness in moral beliefs and religious beliefs have a meaningful relation with the amount and the speed of shift of consuming.

Background: Several studies have demonstrated an increased RISK of congenital hypothyroidism (CH) in girls in comparison to boys.Objectives: The aim of this study was to determine the potential interactions that are able to change the effect of gender on congenital hypothyroidism.Patients and Methods: We conducted a matched 1:4 case-control study in Hamadan Province, western of Iran, from 2005 to 2011. Based on screening program data, neonates with TSH≥10 mU/L and T4≤6.4 μg/dL were considered as congenital hypothyroidism (Cases). Cases and controls were matched regarding the year and place of birth. Data was analyzed using two different approaches including propensity score and multiple conditional logistic regression model.Results: A total of 277 cases and 1036 controls were included in the study. Girls accounted for 57.4% of the cases and 51.2% of controls (P=0.065). Based on the multiple conditional logistic regressions, only the interaction of gender (girl) and birth season (summer) increased the likelihood of CH significantly (OR=3.09; 95% CI: 1.09-8.74; P=0.034). On the other hand, the ORs of the interaction of gender and all other factors (except for birth season) were not statistically significant in CH.Conclusions: Birth season might act as an interaction that is able to increase the RISK of CH in girls. Accordingly, awareness of the birth season could help policymakers who plan preventive programs to reduce the false negative results among neonates, especially girls.

Objective: One of the factors affecting production and employment in one economy is investment. In economic literature, capital formation is the driving force of economic activities and economic growth patterns are based on the use of capital and labor. Despite the importance of investment in production and subsequent employment in the economy, unfortunately, in recent years, capital formation and the level of investment in the country have been very low due to several reasons such as economic instability. Therefore, it has created major problems in the field of production and employment in the country and its different regions, and it is necessary to make a codified and coherent planning to increase production and employment in the country. On the other hand, the first step for planning and making policies for the growth of production and employment is to identify the factors affecting them and to examine the effectiveness of each of these factors. The point that exists in relation to investment at the sector level (different economic sectors) is that the potential of creating production and employment (direct and indirect) of different economic sectors is different from each other. For this reason, investment in different economic sectors can have different effects on production and employment at the level of the sector as well as the whole economy. Among the reasons for the difference in the production potential and direct employment generation of the sectors, we can mention the difference in technology used in different sectors. In this way, some economic sectors have a high direct employment generation coefficient and some others have lower direct employment generation. Among the reasons for the difference in production potential and indirect employment generation of the sectors, we can also mention the difference in the communication and links between the sectors of each of the sectors with each other. Sectors that have more links with other sectors have a high potential in production and creating employment due to a certain amount of investment. Therefore, it can be said that in addition to the total amount of investment in the economy, the relative share of the sectors in the total investment, or in other words, the structure and COMPOSITION of the investment is also effective in the production and employment of the entire economy. The purpose of this study is to investigate the effect of investment expenditure change on changes in output and employment in different economic sectors in Iran.Method: In this study, structural deCOMPOSITION Analysis (SDA) in the input-output model between 2011 and 2016 have been used. To do this, first, the investment demand matrix in the economy was divided into two matrices, one is the investment COMPOSITION (structure) matrix and the other is the total investment matrix. The investment COMPOSITION matrix represents the share of each sector in the total investment in the economy and the second matrix represents the total investment in different sectors of the economy. For the calculations of this study, the input-output tables of the years 2011 and 2016 are needed. The statistical table of 2011 and 2016 was obtained from Iran Statistics Center. In the next step, both input-output tables were aggregated based on the availability of employment statistics in 18 sectors. After that, to remove price effects in research calculations, input-output tables should be converted to constant price. In this study, to eliminate the effect of price changes between 2011 and 2016, the table of 2016 was converted to the constant price of 2011 with the double deflation method. For this purpose, the price adjustment index of eighteen sectors has been used. Finally, this adjustment index was used to convert the 2016 table to the 2011 price.Results: The results of this study showed that the increase in the level of investment (with a constant COMPOSITION) has increased the total production of sectors of the economy by 2361599.59 billion rials, but the change in the structure of investment (with a constant volume) has reduced the total production 5224865 billion Rials. CHANGING the COMPOSITION of investment has decreased 509620 people and CHANGING the volume of investment has increased 3021509 people in the total employment of the economy.Conclusion: Considering the negative impact of the change in investment COMPOSITION on production and employment in Iran's economy, it is suggested to prioritize investment in sectors that have higher production and employment coefficients in the economy.

The world is embroiled in a pandemic of a new coronavirus at the end of 2019 and early in 2020, with such a large scale that it has severely involved the political, economic, and social systems in most countries around the world. The scale of the crisis is so widespread that many experts believe that the post-corona world will be substantially different from the pre-corona world. In the face of this massive epidemic, how people perceive RISK and how to RISK is communicated, plays a central role in deciding and choosing people's behavior. Fighting with this emerging phenomenon requires mobilizing all the possibilities of society and helping all people in the field of empathy and altruism. In this article, we briefly review aspects of the important concept of RISK perception and communication in this pervasive crisis.

The aim of this study was to investigate the effect of using portulaca oleracea as a source of plant antioxidants for feeding fattening male lambs, on carcass traits, meat quality, and oxidative stability. Twenty-one male lambs with an average weight of 24±1.5 kg and 150±15 days old were fed with one of the experimental rations included a diet without portulaca oleracea as control, a diet containing 7.5%, and a diet containing 15% portulaca oleracea, for 84 days. The muscle (Longissimus dorsi) samplewas used to determine pH, chemical COMPOSITION, colorimetric properties, and oxidative stability of meat. Meat lipid oxidation was determined after 1, 7, and 30 days of refrigerated storage using thiobarbituric acid (TBARS). The use of portulaca oleracea in diets improved meat color characteristics such as L, chroma, and Hue. The highest ash concentration and the lowest meat moisture were observed in the treatment of 15% portulaca oleracea (P<0.05). Meat pH was the lowest in the first hour after slaughter but did not differ at 24 h. Compared to the control, in both treatment groups feeding the lambs with portulaca significantly reduced the concentration of Malondialdehyde in the meat of the lambs and increased the meat oxidative stability (P<0.05). The results of this experiment showed that feeding portulaca oleracea by improving properties such as color and increasing the meat oxidative stability improves meat quality, which may have lead to an increase in its nutritional value in terms of human health.