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As near-surface mineral resources are being depleted, mining operations are focused on deepening. Rising environmental concerns prefer underground mining methods because their footprint is less than that of surface mining methods. Among the underground mining methods, block caving is a method with low operating costs and comparable production rate to open-pit mines. Mine design and planning optimization is performed to ensure the optimal use of mineral resources with minimal possible extraction costs. Stope boundary optimization is vital in the underground mining planning process, and numerous algorithms have been proposed in that regard. The floating stope algorithm is the most widely used algorithm which is presented for those mining methods where selective mining is possible. This paper tries to apply the floating stope algorithm for stope boundary optimization in the case of block caving. In that regard, a framework is discussed to determine the input parameters of the floating stope algorithm that are suited for block caving including minimum block size, floating ranges, and cutoff grade. These parameters are defined to customize the floating stope algorithm for the block caving method. Then the customized algorithm is applied to optimize the boundary of the underground block caving stope. Then, the corresponding undercut level is determined using the “effective cross-section” heuristic. The procedure is applied in the Songun copper mine. Based on the results, the minable reserve is 617 million tons with an average copper grade of 0.53%.

The size and the axial and radial velocity distributions of electrically controlled droplets generated from Taylor cone operating in the stable cone-jet regime are simulated by numerical modeling of electrosprays. A model is formulated as function of liquid flow rate, needle-to-counter electrode distance, applied voltage, and electrical conductivity and surface tension of the liquid in a DC electric field is presented with a 2D electrohydrodynamic model. The droplet size reduction can be explained by evaporation and/or Coulomb explosion. Results show that moving downstream, the average velocity of droplets decreases monotonically. This paper reports a numerical study of the effects of an externally applied electric field on the dynamics of drop formation from a vertical metal capillary. The fluid issuing out of the capillary is a viscous liquid, the surrounding ambient fluid is air, and the electric field is generated by establishing a potential difference between the capillary and a horizontal, electrode placed downstream of the capillary outlet. The Primary jet Break-up and droplet transport and evaporation of electrohydrodynamic sprays is investigated by modeling of droplet size and velocity distribution in spray cones and a series of drop migrations under the influence of an electric field were carried out and the results are in good agreement with other theoretical and experimental studies.

Background and Objective:Every educational institution and every learner must adapt to the environment for growth and development and have the necessary skills to meet the changing needs of the society. This has special conditions in higher education and among students and graduates, and they are always expected to adapt to the environmental conditions inside and outside the education system. Using information and communication technologies that are available to them in various forms can be a logical and desirable solution. Purposeful use of these technologies in the field of education is now known as educational technology, which has been expanded on a large scale to increase teaching and learning activities. The student of educational technology is both a producer of information, a consumer, and a link between producer and consumer; and this is where the sense of responsibility comes into play. It is not easy to prepare a curriculum for such students in such a dynamic environment; as it must both meet the needs of students and take into account the changing needs of society and the labor market. At the same time, the mission and nature of the field must be preserved and developed. What is important is that simply issuing the curriculum and implementing it in universities will not be enough. Evaluating and reviewing this program in order to present and suggest a desirable and appropriate curriculum is important and vital. Thus, the aim of this study was to evaluate the curriculum of educational technology from the perspective of graduate students. Methods: Quantitative research was conducted using a survey method. The population, who were senior students of educational technology at senior level in the public universities of Arak, Bu-Ali, Kharazmi and Allameh Tabatabaei in Iran were sampled. Due to limited number of the population, all of them were selected by consensus. Data collection instrument was a questionnaire whose validity was confirmed by 5 experts and with a Cronbach's alpha of .89. The data were analyzed by descriptive and inferential statistics using SPSS. At the descriptive statistics level, the frequency, mean and standard deviation indicators were used and at inferential statistics level t test and Kolmogorov–Smirnov test were utilized. Findings: The results showed that graduate students are not satisfied with master curriculum of educational technology. In other words, final year students who had experienced the curriculum believed that the curriculum was not in line with their needs and expectations. Conclusion: Although the averages were lower than average in all components of the MA curriculum of the major Educational Technology, but there is no reason for the inefficiency of this field and its inappropriate implementation in the country's universities. Part of this dissatisfaction may be due to university management rather than the curriculum. Because universities and departments cannot expect much from professors and students if they cannot provide the necessary facilities and conditions for the implementation of the curriculum. Of course, continuous review and trending of curricula in order to apply this field due to its nature and mission at the national and international levels is an inevitable necessity. ===================================================================================== COPYRIGHTS ©2019 The author(s). This is an open access article distributed under the terms of the Creative Commons Attribution (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, as long as the original authors and source are cited. No permission is required from the authors or the publishers. =====================================================================================

Background: This study aimed to measure the expression levels of peripheral blood miRNAs in brucellosis and their involvement in the different phases of the brucellosis., Methods: The expression levels of miRNAs including miR-210, miR-155, miR-150, miR-146a, miR-139-3p, miR-125a-5p, miR-29 and miR-21 were quantified in 57 brucellosis patients subgrouped into acute, under treatment & relapse phase and 30 healthy controls (HCs) using real-time polymerase chain reaction (RT-PCR). The receiver operating characteristic (ROC) analysis curve analysis was performed to find a biomarker for discrimination of different phases of brucellosis., Results: The expression of miR-155, miR-146a, miR-125a-5p, miR-29, and miR-21 was found to be elevated in the acute brucellosis patients compared to HCs. miR-29 changed in under-treatment patients, while miR-139-3p and miR-125a-5p showed alterations in relapse cases. The ROC curve analysis depicted the potential involvement of miR-21 in the pathogenesis of acute brucellosis., Conclusion: The expression level of miR-21 is significantly augmented in acute brucellosis and has the potential to be a contributing diagnostic factor for acute infection., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Th1 cells play a central role in immunity to brucellosis, while the exact role of Th17 cells has remained unknown. This study aimed to evaluate the peripheral distributions of Th1 and Th17 cells and serum levels of IFN-γ, IL-17A and IL-22 cytokines in brucellosis patients. One hundred patients (36 acute, 41 under-treatment and 23 relapsed) and 30 age- and sex-matched healthy controls were included. The frequencies of Th1 and Th17 cells were determined by flow cytometric analysis. Serum levels of IFN-γ, IL-17A and IL-22 were measured by multi-analyte flow assay. Increased frequencies of Th1 and Th17 cells were observed in acute and relapsed brucellosis versus under-treatment patients and healthy controls (P < 0.05). The mean serum levels of IFN-γ were significantly elevated in acute and relapsed groups compared to under-treatment patients (P = 0.002 and P = 0.01 respectively). Acute patients showed higher levels of IL-22 than under-treatment (P = 0.008). Direct correlations were found between increased frequencies of Th1 and Th17 cells in acute and relapsed patients (P = 0.007 and P = 0.001 respectively) and between IL-17A and IL-22 in both groups of patients. Our findings indicate a cooperative role for Th1 and Th17 cells in immunity to brucellosis which is more evident during acute and relapse phases of brucellosis., (Copyright © 2019. Published by Elsevier Masson SAS.)