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Because of the importance of osmoregulation in success of the juvenile Caspian Roach (Rutilus caspicus) release, maintenance and their restoration, this study was performed with the aim of the evaluation of these fish (average weight of 1.4 g± 0.018 g) to the salinity tolerance of the Caspian Sea by abrupt and gradual transfer methods on two different occasions of short-term (24 hours) and long-term (21 days). For this reason, 360 juvenile roaches were distributed to 9 different experimental treatments (each of them with 3 replicates) with 1) increased abrupt salinity (direct transfer to the Caspian Sea water), 2) increased gradual salinity (3 ppt for every 24 hrs) and 3) the Control group (freshwater). In order to evaluate the ion regulation, osmolality, Na⁺, K⁺ and Cl^- were measured in fish. Some immune responses related to the increased salinity (immunoglobulin and lysozyme) and stress indices (cortisol and glucose) were also measured. Based on the obtained results, the fish in both treatments of increased salinity showed high percentage of survival. All parameters related to ion regulation were decreased after a primary increase. Furthermore, the trend of cortisol and immunoglobulin changes were negatively correlated showing decreased stress response and increased immune system for both salinity transfer methods. Thus, the roach juveniles (1-2 g) are able to be transferred into the Caspian Sea directly.

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Capital structure policy is a mean to tradeoff between risk and return and many factors influencing the optimal capital structure for each company. The aim of this study is to investigate the factors affecting the capital structure of companies listed in Tehran Stock Exchange and some selected stock exchanges in the developed and developing countries, and compare these determinants in a domestic versus international setting. Determinants of capital structure, considered in this research, are in the firm and country levels. In the firm level, profitability distance from bankruptcy, size and the ratio of fixed assets to total assets are used, and in the country level, the role of country’s GDP growth and stock market development is investigated. For international companies, we used Compustat Global Vantage database and World Bank databases and for domestic companies, we used Tadbirpardaz database to collect data. The findings showed the determinants significantly effecting on capital structure in four populations: the whole world, developed countries, developing countries, and Iran. Finally, we found that the developed and developing countries profitability and the size have different effects on capital structure. Alternatively in comparison between Iran and the developed countries, size and the ration of fixed assets have different effects on capital structure.