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Study air infiltration into the building in several ways such as energy, air quality, thermal comfort and pollution entering in the building is very important. In this context, many studies have been conducted in different countries. In our country due to the use of steel doors and windows, do independent research on the gap size and air infiltration is necessary .In this study, by practical view and in order to localize results, based on a field study, the actual dimensions of the gaps around conventional doors and windows in Iran is measured. The results of these measurements are used to simulate gaps, then with experimental study, air infiltration rate of this gaps is calculated at different pressures. In present study, after investigating the effect of different aspects of gaps on air infiltration rate, two common equations, power law and quadratic equation, in order to fitting data were compared. Results show that power law equation can adapt better to the experimental data. Coefficients of the power law equation to estimate the air infiltration rate through the gaps was presented. By analysis of the results, due to the proximity factor of the pressure difference to the number 0.5 in most of the results, it was concluded that the Bernoulli equation can be used to predict the air infiltration rate through the gaps. This equation is better compliance with laws and physical principles. Discharge coefficient of the Bernoulli equation for gaps with different dimensions are calculated.

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Nowadays, modern windows with standard caulking used in most buildings. Study of air infiltration and caulking this windows in several ways such as energy, indoor air quality, thermal comfort and pollution entering in the building is important. In this study consists of two parts, first experimentally investigated the airtight performance of various window gaskets. For this purpose, using 8 different types of gaskets and simulate modern window gap, air infiltration rates measured at different pressure differences. The results show that the airtight performance of various gaskets are different. Also fitted the experimental results by power low equation, and relations and coefficients for calculate air infiltration rate of modern windows (sealed windows), respectively. In the second section due to the very low air infiltration rate of the experimental results, indoor air quality assessed by numerical modeling methods. In the sample model, air infiltration of modern windows as ventilation and human breathing as a source of CO2 simulated. Indoor air quality is weighed by the CO2 concentration in the interior space. The results show that the air infiltration of window gaps to ensure air quality during the 8 hours is not enough. Then, assuming uniform distribution of CO2 in the sample space, and solve the transfer species equation for the problem situation, analytical equation for evaluating indoor air quality were achieved. Analytical results matches on numerical simulation results exactly. The results of this study can be very useful for HVAC engineers.

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Objective: Pathological changes to endothelial cells of the vessel wall may lead to vascular stenosis. In this study, we investigate damages that appear following radiotherapy in two states, single fraction and fractionation irradiation, as an effective sign of cytoskeletal and nuclei structure of vascular wall endothelial cells.
Methods: We irradiated human vein endothelial cells (HUVECs) with a Cobalt-60 therapy machine at radiation doses of 0, 2, 4, and 8 Gy. We stained the skeletal structure of the membrane and nuclei within 24 h after irradiation. This cell line received fractionation radiation therapy at doses from 0 to 8 Gy, in sub-fractions of 2 Gy, after which we stained the cytoskeleton. Morphological parameters such as area and perimeter of the cells and nuclei were determined, and we evaluated the cell shape index (CSI) for cells from each group.
Results:  Increasing the irradiation dose from 0 to 8 Gy led to a significant decrease of CSI (approximately 56%) and a significant increase of nuclei shape index (approximately 85%; p<0.05). The cells’ areas and nuclei doubled (p<0.05). CSI parameter significantly decreased approximately 23% (4.5 times lower) during the radiotherapy fraction after application of the 8 Gy compared with control group cells.
Conclusion: After irradiation, we observed broken the membrane filaments that resulted in a new configuration, which led to increased cell and nuclei sizes along with alterations in the cell shape. Radiation therapy led to dose-dependent changes in morphological behavior response of the endothelial cells. Hence, it would be considered as a prognostic factor for behavior of healthy vascular cells in the process of radiotherapy.