Showing 16 results for Nayeri
Volume 3, Issue 2 (Summer 2019)
Abstract
is one of the most common improved oil recovery method in the world. High residual oil saturation at the end of this method is due to low macroscopic sweep efficiency and viscous fingering. It can be improved by the mobility control during polymer solution injection. In this study, by of silica/ the effect of it on IFT, viscosity, and was investigated. In addition, the performance of in high salinity water was studied by using nano particles. The zeta potential results show that the stability of polymer solution was enhanced in of nano particles in high salinity water condition. Also, the lowest IFT was obtained for contained 1 percent nano silica (18.34 ), and the most tendency to water wet conditions was provided for this concentration. In addition to, 1 percent nano silica/ has the best performance on formation water viscosity and improved the mobility ratio to 1.07, which it can increase the oil recovery.
Volume 5, Issue 4 (Fall 2020)
Abstract
Aim: Pain is a common phenomenon among emergency patients which may lead to chronic pain conditions and alteration of physiological function. However, it is widely reported that proper pain assessment and management, which is often accomplished by adequately trained nurses, reduce the suffering of patients. Therefore, this study aimed to assess the knowledge and attitude of the nurses towards pain management.
Method and Materials: This study has been performed among 187 nurses who working in emergency wards of hospitals affiliated to Tehran University of Medical Sciences (TUMS). Data has been gathered via the Knowledge and Attitudes Survey Regarding Pain (KASRP) tool. Descriptive and inferential statistics were used to analyze data through SPSS software version 16.
Findings: Totally, 187 emergency nurses including 91 female (48.7%) and 96 male (51.3%) entered into the study and completed the questionnairethe study findings showed that most of the nurses (about 57.2%) had low average knowledge and attitude towards pain management. The relationship between knowledge/attitude of nurses with number of assigned patients (p=0.028) and the gender of nurses (P=0.034) were significant.
Conclusion: The study results demonstrate that nurses have low average knowledge and attitude towards pain management which is one of the most important obstacles for efficient pain management.
Volume 9, Issue 1 (10-2019)
Abstract
Considering the vital role of Environmental factors alongside industries’ efforts on effective and efficient use of resources as well as nowadays’ social issues, lead to serious attention to sustainable development. On the other hand, the intensity and necessity of environmental considerations in the steel industry, which has decades of history in Iran, has always been emphasized. Therefore, this paper aims to elaborate the underlying factors of steel industry sustainable development. To this aim, based on prior studies and interviewing experts, the underlying extracted factors scrutinized through ISM approach in order to develop a coherent structure. In the following, the structured factors clustered by MICMAC analysis. In addition, their mutual affects and importance weights, derived by employing ANP on the ISM developed structure. Findings depict that inventory, occupational accidents, human safety and welfare are the most effecting factors of steel industry sustainable development.
Volume 9, Issue 2 (Spring 2018)
Abstract
Aims: Antioxidants in sesame oil, including tocopherols and sesamin have greatly increased the shelf life of it against heat. Following the increase in the expression of the cytochrome P450 enzyme encoder (CYP81Q1), the content of sesame is increased in different stages of development of sesame seeds. The aim of this study was cloning, sequencing, and bioinformatics study of CYP81Q1 gene of Iranian sesame (Seamum indicum L.) cultivar.
Materials and Methods: In the present experimental research, DNA was extracted from leaves and stems of Karaj1 sesame cultivar and the target gene was amplified by PCR. Gene was cloned in binary vector pBI121 and confirmed by 3 methods, including enzymatic digestion, PCR, and sequencing. Then bioinformatics characterization of this gene was studied and the Ramachandran plot was drawn on the three-dimensional structure of the gene.
Findings: Cloning was confirmed. DNA sequencing results confirmed the cloned segment. Molecular weight and predicted isoelectric point of the protein were 57021.3 Dalton and 8.46, respectively. The three-dimensional structure of the protein had a good stroke chain. The sequencing result of this gene showed a difference in the 23 nucleotides of this gene in sesame seeds of Karaj 1 (access number KP771974.1) with a reported sequence in the NCBI gene bank (access number AB194714.1), which resulted in the sequencing of the CYP81Q1 gene in Iranian sesame (Karaj 1) at this database.
Conclusion: Based on nucleotide sequencing, the target gene has 1521 base pairs, and differs from 23 nucleotides with the sample registered at the NCBI World Bank. This gene encodes a protein length of 506 amino acids. This protein is very similar with the registered protein in NCBI.
Volume 9, Issue 2 (summer 2021)
Abstract
Intertextuality theory is one of the new approaches to reading and criticizing texts. This theory first draws from Ferdinand Saussurechr('39')s semiotics and examines the relationships between the texts. Because in every text there are references to earlier works; In other words, new texts are the product of pre-existing texts. Gérard Genette has consummated the theory of intertextuality. Genette divides intertextuality into three categories, which can be examined in the form of: Explicit and announced presence, hidden, not explicit or implicit presence of one text in another. In this article, the “Mousibat nameh”chr('39')s anecdotes are first classified according to this theory, Then the earlier text of the anecdotes is found in the works of the sixth century, After that, the intertextual reading of anecdotes is presented based on the theory of genetics intertextuality in these three areas, along with examples, practical analysis of similarities and differences in terms of volume, characters, goals of the two authors between the anecdotes. According to this study, ten intertextual “Mousibat nameh”chr('39')s relate to sixth-century works. In these two modules, there are five cases of explicit intertextuality, of which two are “Aqd” and two is “Eqtebās” and one is “Translation”. There were also five cases of intentional-hidden intertextuality
Volume 10, Issue 4 (3-2021)
Abstract
Pricing as a basis of revenue management can ensure the maximum expected profit of any business if managed effectively. In competitive markets of perishable products, the prices are vitally set in a dynamic manner according to the product life cycle by different discounts or price recovery strategies. Consequently this study develops an optimization model on dynamic pricing with the aim of maximizing revenue and diminishing the related costs. Considering the product freshness and its impact on demand, the model determines the pricing policy including the increasing or decreasing rate of the price during the sales horizon consist of several time periods equal to the product life cycle. Moreover, replenishment and inventory costs are incorporated in defining the pricing policy for each period. The proposed model implemented for the OK chain store, which results in a suitable pricing policy (decreasing) in line with the revenue increase for the meat and vegetable products of the whole store.
Volume 12, Issue 2 (9-2022)
Abstract
Considering the development of technology and the increasing importance of online food ordering channels, this study aims to compare the effect of online food ordering channels on customers' purchase intention. This research is descriptive-analytical in nature, practical in terms of purpose, and based on the survey method. In the beginning, by reviewing the subject literature, the conceptual model of the research was obtained and led to model hypotheses that were tested by the structural equation modeling and partial least squares (PLS-SEM) approach in two outsourcing channels including Snapfood and the internal website of well-known chain restaurants in Tehran. Findings prove the positive effect of service quality, service attractiveness, and fair price on the perceived value of the distribution channel, while channel reputation has no significant effect on the perceived value of customers. Moreover, the results depict that the perceived value of distribution channels, customer satisfaction, and word-of-mouth advertising has a significant positive effect on the customer's purchase intention through the online channel, although there is an intensive total effect (indirect and direct) of perceived value on the customer's purchase intention In the outsourcing channel, contrary to the internal website.
Volume 13, Issue 3 (4-2023)
Abstract
Most strategic programs assume the future using various methods, and develop a static program based on trend extrapolation from a single future that provides acceptable results in a small set of possible futures. If the future turns out to be different from the assumed ones, the program may fail. In addition to the high uncertainty in predicting the future, planning conditions also change over time. To address this issue, this study seeks to design a model for developing adaptable strategies that can both provide satisfactory performance in multiple diverse futures (Robustness) and adapt to new conditions. The foundations of this research are interpretive, the approach is qualitative, and it is a developmental-applied study. In this study, the literature on developing strategies under uncertainty is examined using the meta-analysis method. Accordingly, after reviewing the literature, 39 concepts (themes) and 10 elements were extracted. Finally, using the identified elements and concepts and the literature of the study, the final model for developing robust adaptable strategies under uncertainty was designed.
Volume 13, Issue 53 (5-2015)
Abstract
The objective of this experiment was to investigate the antimould effect of 19 Lactobacillus plantarum strains isolated from different production stages of Lighvan cheese (3, 8 and 8 strains from raw milk, curd and fresh cheese stages, respectively) a traditional raw milk cheese, on Penicillium expansum (PTCC 89046) as an indicator in fruit juice spoilage. This antimould spectrum was determined by agar spot and well diffusion method, followed by determination the influence of different technological or physico-chemical factors including temperature (80°C for 1 h, 100°C for 10 min, 100°C for 30 min and 121° C for 15 min) and pH( 2 to 7) and different dilution (Titre test) . Serial twofold dilutions were conducted to the CFE in order to assess of CFE Titre against mould indicator. Findings revealed that Lactobacillus plantarum strain C28 has the highest antimould properties in both antimicrobial methods (Agar Spot and Well Diffussion Assay) and antimould effect showed decreasing trend with pH increasing. In 121 ° C for 15 min, no antimould effect was observed. The Lactobacillus plantarum strain C28 showed the highest titre factor of 160 (AU / ml) . Finally, we can assume that these strains which isolated from different production stages of Lighvan cheese or their Cell Free Extract (CFE) can be used as biopreservative in food systems.
Volume 14, Issue 2 (summer 2024)
Abstract
Purpose: In today's world, many decision-making problems are uncertain. The main source of these conditions is the lack and sometimes the absence of information for decision-making, which makes it one of the most challenging and at the same time the most important issues in supply chain management. Therefore, the present study aims to provide a Bi-objective mathematical model of a sustainable supply chain based on uncertain parameters, with a focus on minimizing costs and environmental pollutants. The proposed model can be an efficient tool for designing a sustainable and flexible supply chain network.
Methodology: This research is descriptive-analytical. Furthermore, in terms of its objectives, it is considered an applied type of research. This study developed the Malvey scenario-based method, focusing on the parameters of the two-objective mathematical model, while considering shipping costs, demand, and capacity reduction due to disruptions as uncertainty parameters. In study utilized software tools GAMS, Excel, and Microsoft Visio for data analysis.
Findings: The results indicate that using the mathematical model based on the Malvey scenario in uncertain conditions in a sustainable supply chain can lead to achieving favorable and fruitful results. The mathematical model was able to effectively address demand uncertainty, shipping costs, and capacity reduction due to disruptions, although its performance decreased in scenarios with larger aggregates.
Volume 14, Issue 4 (2-2025)
Abstract
Objective: In analyzing the value chain at the industry level, it is very important to identify the framework of businesses and supplier/customer relationships. The oil and gas industry is the largest energy supplier and economic sector of the Iran. The value chain in the oil and gas industry includes a wide range of markets and businesses from the exploration to the consumption. In this research, the overview of the value chain of this industry was drawn and the government and private structures as well as policy makers and its stakeholders were determined.
Methodology: With the help of experts and using the Delphi method, the general framework of businesses, the goals and performance indicators of a firm and the factors affecting them were identified. Next, a conceptual model was developed to evaluate field development businesses based on the firm's goals, factors affecting the goals, business graftings, and time periods.
Findings: The finalized framework of field development businesses in the oil and gas value chain was drawn at 4 different levels includes 52 active businesses.
Conclusion: The results showed that in the presented conceptual model, 7 main goals and 11 factors are considered in three general categories, including direct influencing factors, factors caused by the business graftings, and macro factors from the outside of industry for each enterprise present in this sector of the industry.
Volume 17, Issue 3 (5-2017)
Abstract
One of the new lubrication methods in machining processes is Minimum Quantity Lubrication (MQL). In this method, a very small amount of fluid by compressed air creates a spray and is used as lubricant. One of the advantages of this method compared to conventional (wet) lubrication is the reduction of environmental pollution and undesired effects on operator health. In the present study, the effect of minimum quantity lubrication on surface roughness in hard turning of 100Cr6 bearing steel has been investigated and compared with dry and wet machining methods. To perform MQL, some equipment have been added to the lathe machine. The tool used for material removal of 100cr6 steel is Nano-CBN that is a new generation of CBN tools with Nano technology. All experimental tests performed in dry, wet and MQL conditions. For investigation of surface roughness, each of cutting parameters include cutting speed, feed rate and cutting depth were selected in three different levels and all possible combinations of these parameters has been tested. According to experimental results and analysis of variance, feed rate 68%, lubrication method 14%, cutting speed 4% and cutting depth less than 1% affected on the surface roughness. The obtained results showed that the surface roughness in MQL method has been averagely decreased 42% and 30% in comparison with dry and wet machining, respectively.
Volume 18, Issue 71 (7-2021)
Abstract
The present study has formed in order to determine the current errors source of Persian leaners at beginner, intermediate and advanced levels. this survey tries to give answer to this question: From what source do current errors and mistakes of Persian leaners originate at beginner, intermediate and advanced levels? To this end, some compositions were prepared from Saadi Foundation Corpus in this address: http://sfcorpus.ir. These data were recorded by foundation instructors regarding years (2015-16) on website and
they belong to Persian learning courses held for Arab, Chinese, Pakistani, Indian and Turkish language learners at six levels (Basic, pre-intermediate, intermediate, upper-intermediate, advanced and upper- advanced). Given research subject, 210 compositions, belonged to 5 Persian-learners from Saudi Arabia, China, Pakistan, India and Turkey were elected in several subjects where each Persian learner gave 14 sheets with totally 70 sheets at any learning- level (Beginner, intermediate and advanced). Then, data were analyzed by descriptive method based on Error Analysis Scale (Keshavarz, 1994) and the acquired results were presented both qualitatively and quantitatively. The given findings derived from this analysis showed that the current errors of Persian learners originate from extra lingual source at beginner level and learning strategy is the factor for current error for Persian learner at intermediate level. Finally, the current errors of Persian learners are related to learning texture at advanced level. The analytical results can be addressed by instructors, authors and educational planners for non-Persian speakers so that to recognize better weak points of Persian learners to select appropriate teaching technique and provide educational textbooks.
Volume 19, Issue 2 (9-2016)
Abstract
Background: Free-living amoebae, including acanthamoeba constitute a large group, which live in fresh water, salty and bitter, moist soil, carious plants and some on the stool and has been considered as a medical important agent. The aim of the present study was to determine the effects of aqueous and alcoholic extract of Artemisia annua on trophozoites and cysts of Acanthamoeba in vitro.
Materials and Methods: In this experimental research, after genotyping the clinical isolate, the aqueous and alcoholic extracts of Artemisia annua were prepared. Then different concentrations (1.25, 2.5, 5 and 10 mg/ml) of aqueous and alcoholic extract of plant as well as artemisinin were tested in three different times (24, 48 and 72h) on trophozoites and cysts of Acanthamoeba in vitro. The viability of the parasite was evaluated by trypan blue, MTT and flowcytometry methods.
Results: Our result, indicated the anti-acanthamoeba activity of different concentrations of the extract of Artemisia. That, in the presence of 10 mg/ml alcoholic extract in medium culture after 72 hours, 30.51% and 91.40% trophozoite and cyst of Acanthamoeba were found alive. However, in the presence of 10 mg/ml aqueous extract of Artemisia annua, 58.25% and 81.53% trophozoite and cyst respectively were found alive in the in medium culture, after 72 hours.
Conclusion: Aqueous and alcoholic extracts of Artemisia annua showed anti-acanthamoebic activity which is dose and time dependent.
Volume 23, Issue 3 (10-2019)
Abstract
Today, according to the international significance of sustainability, scholars aim to develop sustainability assessment models within the banking industry. Since that, the banks affect the development of sustainability within the countries both directly and indirectly. The purpose of the present study is to provide a comprehensive Assessment Model for the Iranian banking system, which evaluates the bank's sustainability through different aspects. Therefore, as implied research with a descriptive mixed method, the study employed a Meta-synthesis approach in order to obtain codes, themes, and categories of sustainability in the banking industry. In the following, ISM structured a network of relationships between the themes as a model while ANP helped to determine the weights of the themes and categories. Ultimately using the content analysis, the sustainability information of the banks extracted to feed the provided model, which lead to the sustainability computation of 27 governmental and non-governmental Iranian banks. As a result, Pasargad Bank ranked first, while Ayande and Melli Banks ranked second and third respectively. Moreover, it became clear that the average sustainability score of non-governmental was higher than governmental banks, while most of them neglect the environmental issues, which needs to be considered in their strategies
Volume 24, Issue 3 (10-2020)
Abstract
Crises are always the hardest test for every management theory. There are few management theories that work in the face of severe crises. As a result, organizations and managers in practice, during major crises, suspend many of their functions, dimensions and tasks. Meanwhile, the field of decision-making has a special status, because this field can’t be closed at all. Accordingly, practical theories of decision making in crisis are one of the most essential needs of any organization in times of crisis. In this regard, we tried to explain the application of PANDA decision-making strategy in critical situations. To this end, the corona crisis was chosen as the focus area. The Corona crisis, as one of the most important human crises that is currently affecting the whole world, is the best option for this purpose. In order to narrow the scope of the research, the decisions of the National Anti-Corona Headquarters of Iran were selected as our cases. Therefore, multiple case study method was selected as the method of the present study. The results of this study show that the characteristics of consequentialism, multiple feedback, speed of action and systematic attitude are the four main characteristics of Panda method that make this method especially suitable for critical situations.
