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Aims: A strong association has been documented between diabetes mellitus (DM) and oral diseases. Since dental clinicians are mainly responsible for the oral health of the general population, this study aimed to assess the knowledge and practice of dental students in Tehran regarding the oral health of diabetic patients.
Instrument & Methods: In this cross-sectional study, a researcher-designed questionnaire with 3 domains and 32 questions (5 demographic, 21 knowledge, and 6 practice questions) was used for data collection. After assessing the validity and reliability of the questionnaire, 130 senior dental students attending Tehran, Shahid Beheshti, Shahed, and Islamic Azad University dental schools were requested to fill it out. Data were analyzed by the linear regression model using SPSS version 20.
Findings: The mean age of the participants was 24.6±2.47 years. The response rate was 94%. Half of the students were females (n=70, 53%). The mean knowledge and practice scores of the students were 15.29±2.32 out of 21, and 4±1.19 out of 6, respectively. The students with a higher grade point average score acquired higher knowledge and attitude scores (p=0.00). A significant inverse correlation was found between the practice and the age of students (p=0.05).
Conclusion: The results indicate the moderate level of knowledge and practice of dental students in Tehran regarding the oral health of diabetic patients. Educational interventions and revision of dental curricula may enhance the knowledge and practice of dental students in this respect.
 

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  In this research, physicochemical properties and oxidative stability of Roghani virgin olive oil grown in two regions of Roodbar and Kazeroon, located in north and south of Iran respectively, with differences in pedoclimatic conditions, altitude and soil were investigated. To determine the physicochemical properties, acidity, peroxide value, spectrophotometric indexes at 232 and 270 nm, smoke point, specific gravity and refractive index as well as the total contents of phenolic compounds, alpha tocopherol, chlorophyll, carotenoid, and fatty acid composition were evaluated. To evaluate the oxidative stability, the effect of heat treatment at 180 °C for 8 hours on indicators such as conjugated diene value, carbonyl value, polar compounds and oxidative stability index were tested. Results indicated the differences in the structural properties and oxidative stability of the oil obtained from two regions. As the oil from Roodbar region with lower altitude, lower average annual temperature, higher average annual rainfall, and specific geographical conditions, contain higher phenolic compounds, alpha tocopherol and oleic acid and also showed higher oxidative stability during heat treatment. But the oil of Kazeroon region with higher altitude, higher average annual temperature, and lower average annual rainfall, had higher linoleic and linolenic acids and exhibited lower oxidative stability during thermal treatment. Therefore the results of this study can be used as a description of physicochemical properties and oxidative stability of Roghani olive oil from two regions of Roodbar and Kazeroon.  

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River bank erosion causes damages to agricultural land, adjacent establishments and widening of river dimensions. Mass failure process of bank erosion is a factor to transport bulk of sediments followed by deposition in downstreams of a river system, which could be an important problem in river management. This research is to investigate internal erosion under different bank and floodplain slopes, By this means, a number of experiments were carried out in a model designed to simulate internal river bank erosion in the laboratory. In these experiments, the scour hole length, resulted from internal erosion and seepage discharge were measured under different hydraulic gradients. Results showed that bank slope plays an effective role in scour hole length and calculated Reynolds number in porous medium. As it was observed that the scour hole length and hydraulic gradient decrease with an increase in the bank slope and porous medium Reynolds number decreases with reduction in the hydraulic gradient.

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One of the most remarkable achievements of finite element method is introducing isoparametric elements. Although these elements are able to use in numerous applications, the lower order isoparametric elements make some difficulties such as shear locking, volumetric locking and hourglass. These issues may improve with an increase in the number of the elements or by increasing the order of the elements, which increases the computational time. Therefore for solving these problems, using the lower order elements with incompatible modes, which enhances accuracy and reduces the computational time, could be considered as an alternative solution option. The aim of this paper is to study the effect of using the incompatible elements on the elastoplastic behavior of isotropic plates and beams under uniform axial and bending loadings. For this purpose, 3D standard elements with eight and twenty nodes and incompatible eight-node elements are used in modeling the 3-D case studies. Besides, the 2D standard elements with four and eight nodes and incompatible ones with four nodes are employed to analyze the 2-D plane stress problems. The obtained results show that using 3D incompatible elements achieves the faster rate of convergence in the solution procedure for obtaining the displacement components and also makes significant run-time reduction. However, there are not any remarkable differences between the obtained plastic Von-Mises stresses using 2D standard and incompatible elements.

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In this study, the buckling and postbuckling behavior of composite laminates with piezoelectric layers subjected to compressive in-plane loading have been investigated. The effects of coupled electro-mechanical field on the postbuckling and bifurcation point in cross-ply and general lay-up sequences have been studied using layerwise theory (LWT). The LWT used in this study for analyzing the piezo-composite laminate is based on the assumptions of the first order shear deformation theory (FSDT). In order to obtain the equilibrium equations, the principle of minimum potential energy has been employed. The obtained nonlinear equilibrium equations have been solved using Newton-Raphson iterative algorithm. Furthermore, the three dimensional finite element analysis has been performed to examine the accuracy of the results obtained using the proposed method. The obtained analytical results are in good agreement with those achieved through the finite element analysis. Obtained results showed that, location of the piezoelectric layers have significant effect on the buckling and postbuckling behavior of the composite plates. Moreover, number of degrees of freedom which is used in proposed method are less than finite element method which, decreased the computational time cost.