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ICSS model has been used in various researches in irrigation canals. Due to the new capabilities of recent versions of the HEC-RAS model and its advanced strategies, this model has also been considered. The combination of upstream and downstream control systems of classical controller with nonlinear channel simulation models (HEC-RAS and ICSS), the way of implement, and the results comparison are the main objectives of this research. The utilization of the rules strategy in HEC-RAS and comparison of the model is the novelty of this research. For this purpose, a controller has been developed for each regulating structure and an operational program has been developed for each turnout in advanced boundary conditions in the Eastern Dez Canal. The results showed that the HEC-RAS model performed very well and showed a lower error value in the upstream control system than the downstream control, and the maximum MAE and IAE were equal to 5.3% and 1.8%, respectively. Also, the water flow is stable most of the time and there are no fluctuations in the water depth. In the ICSS model, almost similar results were observed, so that the upstream control performs better than the downstream control, but there are more depth changes and instability, and the maximum MAE and IAE were obtained as 9.9% and 0.3%, respectively. In terms of discharge delivery indicators, HEC-RAS outperformed ICSS. [ABSTRACT FROM AUTHOR]

Background and Aims: Considering importance of recognizing the position of incisive canal before inserting intraosseous implants and bone harvesting from the symphysis and to preventing from adverse effects after these surgeries, using appropriate imaging method is essential and necessary. Due to the high accuracy measurement and high quality of CBCT and also low received dose to patient ̦ the aim of this study was to evaluate and recognize the position of incisive canal using cone beam computed tomography (CBCT). Materials and Methods: In this study, good quality CBCT mandible image of 60 patients including 32 women and 28 men with average ages of 41.3±2.5 were observed for diagnosing and recognizing the position of mandibular incisive canal using three observers separately. Data were statistically analyzed using SPSS software (version 20.0 for Windows, Chicago, IL, USA) and Chi-square and Fisher's exact tests. Results: Horizontal and vertical assessment was independent from the sex of patients. The incisive canal was recognizable in 89.8 percent of specimens. In vertical dimension, in 57.5 percent of specimens the canal was observed in the inferior one third and in 32.25 percent in the medial one third. In horizontal dimension, in 14.75 percent of specimens the canal was observed in the buccal one third, 52.75 percent in the medial one third and 22.25 percent in the lingual one third. Conclusion: The quality of CBCT imaging and its accuracy and resolution can play an important role in the differentiation and determination of the position of incisive canal.

Introduction: Root canal obturation aims at sealing the root canal system to prevent re-contamination of canal and periapical space. Presence of moisture in canal before obturation may posit a negative effect on the quality of canal sealing. Therefore, this study was conducted to investigate the effect of canal contamination with saliva on apical microleakage. Methods: In this laboratory study, 58 human uni-root teeth were cleaned and shaped for obturation with gutta percha and sealer AH26. In the case group, specimens were contaminated with human saliva immediately before obturation, whereas the teeth in the control group were kept dry. All canals were filled by lateral condensation technique. Moreover, the teeth were placed in methylene blue dye for 3 days. Dye penetration was measured using a stereomicrosope. As a matter of fact, the study data were analyzed via utilizing t-test. Results: A significant difference was found between the two groups in regard with the apical leakage(P

Background and Aims: Considering importance of recognizing the position of incisive canal before inserting intraosseous implants and bone harvesting from the symphysis and to preventing from adverse effects after these surgeries, using appropriate imaging method is essential and necessary. Due to the high accuracy measurement and high quality of CBCT and also low received dose to patient ̦ the aim of this study was to evaluate and recognize the position of incisive canal using cone beam computed tomography (CBCT). Materials and Methods: In this study, good quality CBCT mandible image of 60 patients including 32 women and 28 men with average ages of 41.3±2.5 were observed for diagnosing and recognizing the position of mandibular incisive canal using three observers separately. Data were statistically analyzed using SPSS software (version 20.0 for Windows, Chicago, IL, USA) and Chi-square and Fisher's exact tests. Results: Horizontal and vertical assessment was independent from the sex of patients. The incisive canal was recognizable in 89.8 percent of specimens. In vertical dimension, in 57.5 percent of specimens the canal was observed in the inferior one third and in 32.25 percent in the medial one third. In horizontal dimension, in 14.75 percent of specimens the canal was observed in the buccal one third, 52.75 percent in the medial one third and 22.25 percent in the lingual one third. Conclusion: The quality of CBCT imaging and its accuracy and resolution can play an important role in the differentiation and determination of the position of incisive canal. [ABSTRACT FROM AUTHOR]

Water presence has always been one of the significant fac-tors in creating merriness and exhilaration in landscape design. In the past, due to the fundamental role of water in the structure and identity of the city, the presence of water has had a special effect in shaping the urban landscape and would participate at a variety of scales in city. Aque-ducts are technological achievements in history and culture of this land in the arid cities of the plateau of Iran that had supplied the city>s water with the discovery, guidance and extraction of groundwater and has had a ma-jor role in shaping the landscape of the city. Tehran is one of cities that use this method in shaping water networks since it benefits from groundwater surface and a topographic location. Therefore the elements of this water network and streams that were subterranean crossing place of the aque-ducts are always the key elements in shaping the landscape of Tehran. Tehran was provided with s structure based on its designers> thoughts which supplied people's requirements in the city. Following the master and development plans of western approaches, people's requirements and presence of natural elements in the city were eventually ignored. Having destroyed the streams which were responsible for supplying water storages and reservoirs and turned them into dumping places, they were no longer considered as essential elements in city landscape. Aside from losing their functional role and people's conceptual rupture from natural processes, they have lost their reminiscent and mental role. Paying attention to Tehran streams as one of the landscape elements of the city and using this element in urban design and landscape archi-tecture at neighborhood scale can help making proper landscape in the context of neighborhood and provide freshness and vitality. In between at-tention to subterranean aqueducts as one of the main pillars in water sup-plies for non-potable usages, landscape and various facilities in Tehran needs to be studied, identified and organized which can be an effective in strengthening Tehran urban identity. Tehran streams as vital capillaries of city can strengthen the city's identity with changing quality of urban spaces and can have an effective role in citizens' perception of the City rather than offering a destructive role. Natural infrastructures can be an effective matter way in promoting citizens' perception of the city and create a sense and identity of place. Sustainable way of developing nature presence in the city is investing on the potential and internal capabilities of the system. Tehran subterranean aqueducts as available natural vital vessels in the city were one of impor-tant and effective element in shaping the landscape of Tehran. The way of nature presence and influence recovery at least in Tehran city spaces is rehabilitation of the capillary of this natural flow or streams. [ABSTRACT FROM AUTHOR]