2 - 5,5 cm mosquito fishes (Gambusia affinis) were collected from brooks of Baghdad university . This study aimed to identify the histological structure and embryonic development of the gas bladder . The results revealed that the gas bladder of the adult fish consists of single chamber, paraphysoclistous , and its wall consist of three layers. The primordium of the gas bladder appears in 2,5 mm fish embryo as an evagination from the right side of endoderm of foreguts wall. This primordium consists of two thecae, inner, is simple columnar epithelium and outer originates from undifferentiated mesoderm. Simultaneously with the appearance of gas gland in the ventral side of the sac in 4 mm embryo, morphological and histological changes have taken place for it. However the pneumatic duct protrude Change occurs in the site of pneumatic duct in 5mm embryo from the right side into dorsal right side of the forgut wall. In 7mm embryo , the wall of the gas bladder distinguish in to three layers and the endothelium of it consists of changeful epithelium (in 8<5mm embryo). The gas bladder of 10mm larva is a similar with that of adult fish . The endothelium of it changes to simple squamous epithelium except that of ventral side, and the gas bladder transform to paraphysoclistous
Sustainable human development means meeting the basic needs of society and striving for continuous improvement in quality, as it seeks to increase economic well-being while providing adequate housing and nutrition, as well as providing electricity, water, health and education services . Ten centuries ago, Islam highlighted the importance of the development effort and the necessity of its sustainability before the West took it in the 1970s. There are a number of challenges that greatly affect the reality of achieving and ensuring Millennium Development Goals. The research recommends the importance of fighting administrative and financial corruption, as this is one of the biggest challenges facing the possibility of advancing the economy and
... Show MoreThis study aims to formulate an alternative solution for Formalin for preserving fish as study specimens for long periods. The main reason for finding a solution instead of formalin is to get rid of the negative effects of this solution on those who work with it, as well as to better preserve the bodies of fish. Hence, three new solutions were proposed to replace formalin. Thus, Formalin, in turn, may enter the composition of a small part of these solutions to give better results and for long periods of keeping specimens. All solutions prepared in this study participated in being acidic as in formalin. Two solutions succeeded in compensating for the use of formalin in preserving fish
The bubble columns are widely used as a two or three phase reactor in industrial chemical process such as absorption, biochemical reactions, coal liquefaction, etc. To design such a column, two main parameters should be taken in consideration, the gas hold-up (), and the liquid phase mass transfer coefficient KLa. The study includes the effect of gas velocity and the addition of alcohols on gas hold-up and mass transfer coefficient in bubble column with draught tube when the length of the column is 1.5m and the ratio of the draught tube diameter to the column diameter equals 0.5 and the air dispersion into the base of the draught tube using a multi hole tuyere is equivalent to a diameter of 0.15 mm and
... Show MoreThe rate of gas induction was measured in gas-inducing type mechanically agitated contactors provided with two impellers. A reactor of 0.5 m i.d. was used with a working capacity of 60 liters of liquid. Tap water was used as the liquid phase, and air was used as the gas phase. The bioreactor mixing system consists of two equal diameter stirrers; the top impeller is shrouded-disk/curved-blade turbine with six evacuated bending blades, while the bottom impeller was disk turbine. The impeller speed was varied in the range of 50 to 800 rpm. The ratio of impeller diameter to tank diameter (D/T) and the submergence (S) of upper impeller from the top were varied. The effects of clearance of lower impeller from the tank bottom (C2) an
... Show MoreThe auditor has a role in allocating joint costs in the gas industry, and the auditor's procedures are considered as systematic critical examination, analysis and evaluation of everything related to costs in general and joint costs in the gas industry in particular, with the aim of controlling the joint costs of gas industry products, and knowing the share of the cost of each product from the total industry costs Gas products reflect the reality of the company's performance by discovering weaknesses, defects and any errors, to ensure increased effectiveness and efficiency of the parties concerned with auditing them and imposing control and control over the company's resources, as well as
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