Aim: The aim of this study was to compare the effects of Ethylen glycol tetra acetic acid (EGTA) and EDTA for their smear layer removal capability using scanning electron microscopy technique.Material and Methods: A group of 28 single rooted teeth were instrumented to size 60 master file. Four teeth were also kept as control while the remaining teeth were divided into two groups. Group A: in which 12teeth were irrigated with 10 ml of 17% EGTA for 2 minutes? Group B: consisted of 12teeth irrigated with 10 ml of 17% EDTA for 2 minutes. Both groups were then irrigated with 10 ml of 5% Naocl. the control group were just irrigated with 10 ml of 5 % Naocl. All teeth in then the control group were only irrigated with 10 ml of 5% Nacl. Specimeus were then sectioned longitudinally. A scanning electrone microscope was wsed to in vetig ate the intenal surfaces of the canal.Results: EGTA chelated dentin surface more conservatively than EDTA without causing erosion.Conclusion: It seems that EGTA can be used safely to remove smear layer from the canal surfaces.

The sensitivity of lead dioxide coating properties to the deposition conditions and electrolyte composition has allowed the preparation of coatings with different properties for different applications. In this study, the effects of electrolyte additives on the electrodeposition process were investigated using electrochemical measurements such as cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy. The results showed that the presence of fluoride ions significantly reduce the possibility of TiO2 formation. The addition of copper ions not only prevents lead loss at the cathode, but also leads to the formation of copper oxide on the surface at initial stages, which hinders nucleation of PbO2. The presence of sodium dodecyl sulfate (SDS) also interferes with the nucleation process as it occupies active nucleation sites. The α-PbO2 interlayer prevents copper oxidation and solves the problem of lead dioxide nucleation. Finally, it was found that the simultaneous use of all additives together with the α-PbO2 interlayer has a positive effect on the coating process.

Environment and its conservation is one of the present issues in risky modern life. Although, the present world has been improving during last years, it hasn’t been able to solve environmental problems and it has caused its deterioration. Littering in jungle, seashore, public places and passages is one of the significant environmental issues in society of Iran. The Purpose of the present study is investigation of the reasons of littering formation by the approach of Causal Layered Analyses (CLA) and planning scenario. The present study analyzed the layers forming the present social issue and searched the origin of it. In order to accomplish this study, 15 experts in environment and society were interviewed by Qualitative and exploring method and applying deep interview technique. Then, after exploiting the contents and content analysis of interviews, their opinions presented in 4 forms as litany, systematic, discourse analysis and metaphor. By applying the present discourses, the gap between state-people and people-people were recognized as important variables and were applied in presenting scenario. Finally 4 scenarios presented in a diagram which can help strategists and officials of the society.

Medicinal plants contain active ingredients in one or some of their organs. Squalene is one of the active ingredients that prevent heart attacks and cardiovascular diseases and protect the body from some cancers. The aim of the present study was to investigate the presence of squalene in a number of medicinal plants. In this experiment, the plant oils were extracted and measured using Bligh & Dyer with minor changes. TLC (thin layer chromatography) was used to identify squalene. Comparison of TLC of standard squalene with TLC of the investigated medicinal plant samples showed that Caryophillium aromaticus, Descurainia sophia, Portulaca Oleracea, Papaver somniferum and Nigella Sativa contained squalene. Although the percentage of Papaver somniferum and Nigella Sativa seed oil was higher than other medicinal plants, the squalane spot of clove plant had a higher intensity of color and this indicates a higher concentration of squalene in this plant.