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Objective: Endothelium is a selective and permeable membrane for transferring nutrients and vital components to arterial wall. Endothelial damage might lead to altered biological function of endothelium and clinical consequences such as atherosclerosis. Blood pressure pulse always exerts circumferential tension to the arterial wall. Hence, such tension together with other loads, play important role in functional properties of endothelial cells. Previous studies verify effects of cyclic loading on adaptation and remodeling of endothelium. This study investigates structural properties of cultured endothelial cells subjected to uni-axial cyclic loading. Materials and Methods: Human umbilical vein endothelial cells, prepared from national cell bank of Iran (NCBI-C554), were cultured on silicon membrane, and then subjected to cyclic tension with 10 % amplitude and 1 Hz frequency, and 2,4,6,8 hour durations utilizing a custom made tensile device. Viscoelastic properties of endothelial cells were examined by micropipette aspiration technique. Results: Results show increase in elastic modulus (E) of cells due to tensile cyclic loading which results in stiffening of cell body. Also results show primary increase then subsequent decrease in viscose modulus. Conclusion: Previous studies verify generation of stress fibers due to accumulation and increase in actin fibers in endothelial cells after tensile cyclic loading. Since mechanical and structural properties of endothelial cells depend on actin fibers, results of this study show tensile cyclic loading causes increase in stiffness of endothelial cells through generation of stress fibers.

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Objective: Premature ovarian failure (POF) is one of the most important reproductive diseases in women under 40 years of age, which affects the quality of life and longevity of these people by causing short-term and long-term complications.
The incidence of POF is a chronic process that takes several years to develop. The patient went through stages such as premature ovarian insufficiency (POI) and decreased ovarian reserve (DOR), in the early stages of the disease decreased ovarian function efficiency (POI) and then with further progression of the disease, the patient decreased ovarian reserve and further reduce their performance. As the disease progresses, the person eventually develops premature and complete ovarian failure, or POF studies have shown that many factors, including surgical trauma, autoimmune diseases, certain drugs, vaccines, and genetic factors, play a role. Genetic studies have shown that several genes are involved in the development of this disease. Part of the regulation of the expression of these genes is the responsibility of small genetic factors called miRNAs.
Materials and Methods: In the present study, bioinformatics information of miRNAs involved in this disease was investigated. For this purpose, genetic databases such as UCSC, NCBI, KEGG, MIRBASE, TARGET SCAN, STRING, etc. were used to access the genes involved in this disease, structural and functional communication, messaging pathways and regulatory miRNA.
Results and Conclusion: The results of this study indicate that three factors, miRNA-187, miRNA-33b and miRNA-33a, are very effective in the development and progression of this disease.

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Objective: Cell vital function has correlation with mechanical loadings that cell experiences. Here, effects of in-vitro combined cyclic-static stretch on proliferation of human mesenchymal stem cell (HMSC) were evaluated. Materials and Methods: HMSCs were cultured on gelatin coated elastic membranes, and exposed to stretch loading. Four different regimes of cyclic, static, combined cyclic-static, and cyclic with a period of unloading were exerted on the elastic membrane. Duration of cyclic loading and static loading was 5 and 12 hours respectively. Results: The results illustrate that 10% cyclic stretch causes cell alignment but there were no significant proliferation differences between control and test group. Combined cyclic-static stretch reduced proliferation significantly while cyclic stretch with an unloading period increased cell proliferation significantly. At last, static stretch did not affect cell proliferation significantly. Conclusion: Cell stretching regimes and post-loading duration are effective factors on cell proliferation.

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The present research was carried out under hydroponic culture to evaluate the interaction between salicylic acid (SA), nickel (Ni) on vegetative and reproductive growth of strawberry plants as a factorial experiment in a completely randomized design. Well-rooted daughter plants of Pajaro cultivar, were potted in 3 L plastic pots and were sprayed with SA at concentrations of 0, 1, 2 and 3 mM and NiSO4 at 0, 150 and 300 mg.L-1, after establishment. Results indicated that SA at 2 mM increased root and shoot fresh weight, number of inflorescences and fruits, fruit nitrogen concentration and yield. The effect of Ni was promoting too, as 150 mg.L-1 of Ni led to significant increments of fruit number, inflorescences, leaf area per plant and yield. However, the best results were found when SA was applied accompanied by Ni.

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Manufacturing in as short time as possible, with highest quality and at minimal cost, is one of the key factors in industry. As a result, researchers are seeking new methods and technologies to meet such requirements. Liquid impact forming is one of such methods which has received wide currency especially in automotive and aerospace industries. In this method, which is considered as one of tubular hydroforming processes, forming is achieved by using liquid pressure. In this paper, liquid impact forming process was investigated experimentally and numerically for a thin-walled aluminium tube. In experimental part, a die was designed and manufactured to transform the cross section of the aluminium tube into a polygon which at the end of the process changes the cylindrical shape of the tube to a profile almost similar to a trapezoid. Results showed that a die in the form of matrix molding is not suitable for this type of geometry in such a process while using another die which consisted of three parts resulted in a satisfactory forming. Simulation of this process was further implemented using finite element method and results relating to Von Mises stress distribution, displacement, strain energy, internal energy, thickness variation and the force required to implement the process were obtained. Displacement distribution in different regions indicated that no wrinkling occurred in the sample. Comparison between simulation and experimental results indicated that they were in good agreement.