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This paper presents a computational fluid dynamics (CFD) simulation to investigate the effects of the obliqueness of cylindrical weirs on the flow velocity distribution, the pressure distribution and the distribution of water depth over the weir crest. Three different cylindrical weirs with diameters of 0.114 m, 0.09 m, and 0.0635 m, with three dissimilar inclination angles of 90°, 135°, and 150° were used. The SSG Reynolds stress turbulence closure model was utilized in the analyses. The results show that the flow patterns are affected by the inclination angle with respect to the flow direction. It was noticed that inclination angle increment increases the velocity of flow at the downstream surface of the weir, thus increases the absolute value of the negative pressure, at the inward-moved end of the weir. The outward-moved end of the weir was observed not to be covered with water and extending with the increase of the inclination angle. Key words: oblique cylindrical weirs, computational fluid dynamics, SSG Reynolds stress model, pressure distribution, CFD. Ce papier presente une simulation de mecanique des fluides numerique MFN pour etudier les effets de l'obliquite des seuils cylindriques sur la repartition de vitesse d'ecoulement, la repartition de la pression et la repartition de la profondeur de l'eau sur la crete du seuil. Trois seuils cylindriques avec des diametres differents de 0.114 m, 0.09 m et 0.0635 m, avec trois angles d'inclinaison differents de 90 °, 135 ° et 150 ° ont ete utilises. La contrainte turbulence aux modeles de fermeture de Reynolds SSG, a ete utilisee. Les resultats montrent que les modeles d'ecoulement sont affectes par l'angle d'inclinaison par rapport a la direction de l'ecoulement. On a remarque que l'augmentation de l'angle d'inclinaison amplifie la vitesse de l'ecoulement a la surface en aval du seuil, donc augmente la valeur absolue de la pression negative, a l'extremite du seuil deplace vers l'interieur. On a observe que l'extremite du seuil deplace vers l'exterieur n'etait pas recouverte d'eau et prolongeait avec l'augmentation de l'angle d'inclinaison. Mots-cles: seuils cylindriques obliques, mecanique des fluides numerique, SSG modele aux contraintes de Reynolds, repartition de la pression, MFN., Introduction A number of theoretical, experimental, and numerical studies have been conducted to describe the flow behavior within and over hydraulic structures in open channels (Velasco et al. 2003; Acharya [...]

Background: Providing an apical stop in open apex roots is one of the endodontic challenges. The aim of present study was to compare the surface hardness of both mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) cement at different setting situations. Materials and Methods: A total of 40 freshly extracted human teeth with a single root and normal apex and no obvious caries or curvatures were selected. The teeth were sectioned horizontally from the cement enamel junction and 2 mm above the apex. Standard technique was administered for cleaning and shaping of the canals. Open apex root canal was prepared by using Peso reamer. The prepared teeth were randomly divided intofour groups in which two groups were filled by MTA and the other groups were filled by CEM. White MTA and CEM cement plugs were prepared and condensed up to the apical end. In two groups, moistened paper point was placed in the canals and in the other group dried paper points was used. Vickers test was done to evaluate the microhardness and the collected data were analyzed by Kruskal- Wallis and three-way ANOVA tests using SPSS software version 18 at a significant level of 0.05. Results: The highest and lowest surface hardness was observed in CEM group at dried condition with 4 mm thickness indentation (145.10 ± 7.60 kg/mm2) and moist MTA group indented at 8 mm thickness (111.25 ± 5.37 kg/mm2). However, no significant difference was noticed (P > 0.05). Conclusion: Humidity condition might not influence the microhardness properties of both MTA and CEM cement apical plugs at different tested indentation thickness. [ABSTRACT FROM AUTHOR]

Objective(s): The aim of this study was to improve flowability and compressibility characteristics of starch to use as a suitable excipient in direct compression tabletting. Quasi-emulsion solvent diffusion was used as a crystal modification method. Materials and Methods: Corn starch was dissolved in hydrochloric acid at 80°C and then ethanol as a non-solvent was added with lowering temperature until the formation of a precipitate of modified starch. Flow parameters, particle size and thermal behavior of the treated powders were compared with the native starch. Finally, the 1:1 mixture of naproxen and each excipient was tabletted, and hardness and friability of different tablets were evaluated. Results: Larger and well shaped agglomerates were formed which showed different thermal behavior. Treated starch exhibited suitable flow properties and tablets made by the treated powder had relatively high hardness. Conclusion: It was found that recrystallization of corn starch by quasi emulsion solvent diffusion method could improve its flowability and compressibility characteristics. [ABSTRACT FROM AUTHOR]

Refrigeration systems needs efficient refrigerant to perform it's determined objective, so, an optimum refrigerant, must have a good and desirable characteristics as compared with other refrigerants as well as a high coefficient of performance for the working cycle, which results for minimizing operating power to attain determined refrigeration capacity. A variety kinds of improved refrigerants had been appeared within the last twenty years, and many countries did large efforts to phaseout some refrigerants, or at least reduce it's usage, that's for it's ozone layer depletion and it's bad influence on environment and climate. This research deals with a comparative study between many Refrigerants on the basis of it's characteristics , COP and compressibility factor in ejector refrigeration system to select the optimum to be used in this system. From this study results , the optimum refrigerant is Butane (R - 600), which have a good characteristics , a relatively high compressibility factor values , and a COP value of (0.615) , which is a good result as compared with other refrigerants included the phaseouted for it's bad influence on environment and climate. [ABSTRACT FROM AUTHOR]

This research deals with making a mathematical model for the design of a dual system for hot water production for industrial purposes as well as cooling using an ejector at a determined operating conditions, by utilizing dissipated thermal energy from a steam boiler and for a cooling capacity of (15) KW. For the system simulation, mathematical relations were presented for each component which were then combined together and programmed using (matlab) version 6.5 to optimize the system performance and design the components at this situation, using refrigerant (R-123) as the working fluid because of it's good characteristics and relatively high efficiency after a comparison study with other suitable refrigerants to be used for this system. Satisfactory results were obtained having good agreement with previous researches and a COP value of (0.667). The results show a suitable size of the designed system such that it can be used in a wide range of cooling and hot water production purposes. Also, the effect of operating conditions variation on the quantity and temperature of hot water and system performance were studied. [ABSTRACT FROM AUTHOR]

Background: Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder in females. Nesfatin-1 is a neuropeptide synthesized in the hypothalamus and other peripheral organs, and there are conflicting opinions about its correlation with PCOS., Objective: This study aims to investigate the correlation between nesfatin-1 and PCOS and evaluates the effectiveness of nesfatin-1 as a biomarker for the detection of PCOS in women., Materials and Methods: A systematic review and meta-analysis were conducted to identify pertinent articles from databases such as PubMed, Web of Science, Cochrane, EMBASE, Scopus, and Google Scholar. The standardized mean difference (SMD) and 95% confidence interval (CI) were calculated using a random effects model to compare group outcomes. Additionally, meta-regression and subgroup analysis were performed to elucidate sources of heterogeneity., Results: The meta-analysis involved 12 studies with 1222 participants, and the findings revealed a significant relationship between PCOS and nesfatin-1 levels. The pooled (SMD = 0.54; 95% CI: 0.00-1.07; p = 0.04) indicated a significant difference between the evaluated groups. Moreover, a subgroup analysis showed that there was a substantial difference in nesfatin-1 levels among women with PCOS and higher homeostatic model assessment for insulin resistance ratio (SMD = 1.46; 95% CI: 0.92-2.00; p < 0.001)., Conclusion: Our meta-analysis indicates an association between high nesfatin-1 levels and PCOS. This suggests a potential role of nesfatin-1 in the development of PCOS and proposes it as a potential diagnostic biomarker for the disease. However, further research is necessary to validate these findings., Competing Interests: The authors declare that there is no conflict of interest., (Copyright © 2023 Bahreiny et al.)

Background: Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder with complex pathogenesis and metabolic complications, such as insulin resistance. Among the new markers, preptin seems to play a significant role in metabolic disorders., Objective: This meta-analysis was conducted to determine the relationship between circulating preptin levels and PCOS., Materials and Methods: A systematic review and meta-analysis was performed to identify relevant articles in electronic databases such as PubMed, Web of Science, Scopus, Cochrane, EMBASE, and the Google Scholar search engine, using a predefined search strategy. A random-effects model was used to combine standard mean difference (SMD) and 95% CI to compare results between groups. Meta-regression and subgroup analysis were also performed to reveal the sources of heterogeneity., Results: The meta-analysis encompassed a total of 8 studies and 582 participants. The results indicate a statistically significant association between PCOS and serum preptin levels, with a pooled standardized mean difference (SMD = 1.35; 95% CI]: 0.63-2.08; p < 0.001). Further analysis suggested a significant difference in serum preptin levels between women with PCOS and higher homeostatic model assessment for insulin resistance ratio (SMD = 2.40; 95% CI: 1.17-3.63; p < 0.001) within the subgroup., Conclusion: Our meta-analysis shows that increased serum preptin levels are associated with PCOS, suggesting that preptin may be related to the pathogenesis of PCOS and may be recognized as a novel diagnostic biomarker for PCOS. However, further studies are needed to confirm our results., Competing Interests: The authors declare no conflict of interest., (Copyright © 2023 Bahreiny et al.)

Due to the budgetary deadlines and time to market constraints, it is essential to prioritize software requirements. The outcome of requirements prioritization is an ordering of requirements which need to be considered first during the software development process. To achieve a high quality software system, both functional and nonfunctional requirements must be taken into consideration during the prioritization process. Although several requirements prioritization methods have been proposed so far, no particular method or approach is presented to consider both functional and nonfunctional requirements during the prioritization stage. In this paper, we propose an approach which aims to integrate the process of prioritizing functional and nonfunctional requirements. The outcome of applying the proposed approach produces two separate prioritized lists of functional and non-functional requirements. The effectiveness of the proposed approach has been evaluated through an empirical experiment aimed at comparing the approach with the two state-of-the-art-based approaches, analytic hierarchy process (AHP) and hybrid assessment method (HAM). Results show that our proposed approach outperforms AHP and HAM in terms of actual time-consumption while preserving the quality of the results obtained by our proposed approach at a high level of agreement in comparison with the results produced by the other two approaches.