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Volume 24, Issue 5 (11-2024)
Abstract
Cyanide is a highly toxic and hazardous pollutant commonly found in the wastewater generated by mining, electroplating, and petrochemical industries. The current research aims to evaluate the efficiency of advanced oxidation techniques such as UV, O3, and UV/O3 combination, to eliminate cyanide from synthetic wastewater. All experiments were conducted in a semi-continuous reactor to investigate the impact of various operating conditions, such as initial cyanide concentration, reaction time, reaction kinetics, and pH. In this study, degradation tests were conducted on cyanide at four different concentrations (50, 100, 200, and 250 mg/L) and two pH levels (10 and 11). The reaction duration ranged from 0 to 90 minutes, with varying lengths. All experiments maintained constant operational parameters for the process, except for the variable being tested. The UV process alone is not very effective in removing cyanide from wastewater. This is because the low absorption coefficient of cyanide in the ultraviolet region limits the performance of UV in cyanide degradation. Additionally, cyanide is a relatively stable compound that requires a high amount of energy to break bonds and destroy them. Therefore, the use of the UV process alone is insufficient for the complete and safe destruction of cyanide from wastewater. It is necessary to combine it with other advanced oxidation processes to effectively remove cyanide from wastewater. According to the results, it was found that the effectiveness of removing cyanide through a single ozonation process was higher at pH 11 as compared to pH 10. The optimal conditions for achieving the highest level of cyanide removal, which is 68%, were found to be a single ozonation process with an initial concentration of 50 mg/L and a reaction time of 80 minutes. The higher efficiency of cyanide degradation at higher pH can be attributed to the greater production of hydroxyl radicals, resulting in an increase in the oxidizing power of the process. The efficiency of cyanide degradation in synthetic wastewater can be greatly improved by using the combined UV/O3 process. In this method, the rate of cyanide degradation is higher when the pH value is lower. This is because the integrated UV/O3 method is strongly dependent on the concentration of hydroxide ions and hydroxyl radicals, which are affected by the pH value. Therefore, the effect of pH value on the efficiency of cyanide degradation by the combined UV/O3 method is significant. When UV and O3 were combined, over 50% degradation occurred in 40 minutes due to increased degradation rate. The highest efficiency for cyanide degradation was achieved at pH 10 and an initial concentration of 50 mg/L using the combined UV/O3 method. The reaction time was 50 minutes and the efficiency was 100%. First and second-order kinetic analyses were conducted for UV, ozone, and combined processes to study their effectiveness in cyanide degradation. The results showed that the combination of UV and ozone was the most effective method for total cyanide degradation from wastewater compared to the other processes studied. Therefore, UV/O3 can be considered as the optimal analytical method for cyanide degradation from wastewater.
Volume 24, Issue 6 (11-2024)
Abstract
Retaining structure or retaining wall is a wall that acts as supporting structure and the stability of another structure. This wall is used for preventing collapse of soil and generally wherever lateral support is needed. The retaining wall can be designed as gravity, cantilever and supported. Considering that the retaining walls are essential in protecting the related structures to them, therefore, studying the dynamic behavior of these structures is very important due to the financial and human damages. Such structures should be stable against the forces acting on the wall. In addition to static loads, which are always an inseparable part of the calculations of such walls, forces such as cyclic forces caused by the movement of machinery and also dynamic forces caused by earthquake occur on the wall during the period of operation. These forces can be effected on retaining walls and should be investigated and evaluated. Trying to investigate and analyze the dynamic behavior of different retaining walls is one of the most challenging for different researchers.
The wavelet theory in the dynamic analysis of the issues related to civil engineering is going to be widespread. This research aims to investigate the effect of using wavelet theory in the dynamic analyses of concrete retaining walls. For this purpose, a soil medium along with concrete retaining walls with different dimensions (heights) are considered. Dynamic analyses are performed based on the finite element method. In the first stage of modeling, the Sarpol-e Zahab earthquake record is filtered during four steps using the discrete wavelet theory. The numerical models are prepared and subjected to the available records. The percentage of the difference in the results of the analyses done with the records obtained from the different steps of filtering record with wavelet compared to the analyses done with the main record, along with the reduction of the time consumption, is evaluated. As expected, the best match of the post-filtering results to the main earthquake results is for the first-step filter. It can be seen that even the first step filter reduces the analysis time by about 60%. Based on the obtained results, the difference between the results obtained with the filtered records becomes less compared to the main earthquake with the increase in the height of the wall. It has also been observed that acceptable results are still obtained, and the analysis time is reduced by almost 80% until the third step filter.
It should be noted that the Mohr-Coulomb behavioral model is used in the conducted analyzes in this research. This behavioral model is not inherently able to model hysteresis damping behavior at low strains. Therefore, this issue can affect the results of deformations and stresses obtained from dynamic analysis. However, the purpose of this research is to evaluate the performance of the wavelet in the dynamic analysis of the retaining wall. Considering that in all the analyses (both the performed analysis with the main earthquake and the performed analyzes with the wavelet filtered records) the same structure and trend are used, it can be concluded that the effect of using the wavelet compared to the main earthquake gives an acceptable overview and quality
Volume 24, Issue 7 (July 2024)
Abstract
The compound droplets resulting from water-in-oil-in-water emulsions have many applications, including in the food, pharmaceutical and cosmetic industries. Investigating the effective parameters in the production of these droplets plays an important role in their controlled production. In this numerical study, the production of compound droplets in a three-phase axisymmetric glass capillary microfluidic device is investigated. The structure of this system consists of two co-flow and one flow-focusing devices. In this study, the volume of fluid (VOF) method is used to solve the governing equations in different phases. 5 dimensionless parameters are selected to check the effect of each component on the diameter, the generation frequency, and the breakup length of the compound droplets. This study has successfully predicted the formation of compound droplets in the droplet regime. The simulation results show that with increasing the ratio of inner nozzle diameter to outer tube diameter, the core diameter enhances and the shell thickness decreases. By decreasing the angle of the inner nozzle tip, the drop regime changes to the jet regime. By increasing the contact angle of the middle phase with respect to the outer phase in the outer tube wall from 90 to 120 degrees, the frequency of droplet generation increases by 22%. The results of this study can be used for applications such as 3D cell culture.
Volume 25, Issue 1 (4-2021)
Abstract
Today, human life has become increasingly like games, not just because games have become a big part of human life, but most of the activities, systems and services are game-based. Therefore, the main challenge for organizations in the current digital age is to use skill-based game systems to enhance employee motivation and learning. The main purpose of this study was to investigate the game-based capabilities of learning management systems (LMS). This research, in terms of purpose, is in the field of applied research and in terms of method, in the form of qualitative-quantitative research. In first, a number of seven capabilities were identified by studying theoretical background and empirical background and obtaining expert opinions. The statistical population of the study includes professors as well as administrators and experts. The number of ten of them were selected as sample members. Data collection tool was a researcher-made questionnaire whose validity was confirmed by content analysis method and its reliability by Kendall's coefficient. To analyze the data was used the CRITIC-COPRAS approach. The results show that among the four types of learning management system studied, iSpring LMS received the highest score. Finally, discussion and conclusions are presented.
Volume 25, Issue 1 (1-2023)
Abstract
Research on natural compounds provides new alternatives for effective and sustainable control of plant viral pathogens. Herein, we prepared and investigated the in vitro antiviral activity of 60 plant species from 22 families. The hydroethanolic extracts of Rhus coriaria, Chenopodium quinoa and Ailanthus altissima have strong inhibitions on Tobacco Mosaic Virus (TMV) infection. Hydroethanolic extract of C. quinoa with half-maximal Effective Concentration (EC50) value of 1.64 mg mL-1 exhibited the highest inhibitory effect against TMV. The extracts of R. coriaria and A. altissima with EC50 values of 2.82 and 4.42 mg mL-1, being compared with C. quinoa, showed an anti-TMV activity at higher concentrations, respectively. The systemic assay indicated that all of the three extracts reduced the symptoms and negative effects of TMV on tobacco plants. The chemical analysis of C. quinoa extract demonstrated a rich profile of saponins and anthocyanins, while A. altissima and R. coriaria extracts were rich in phenolic compounds. These results displayed that C. quinoa, R. coriaria, and A. altissima extracts had significant antiviral activity, and could be used as suitable sources for discovering new antiviral agents.
Volume 25, Issue 1 (1-2023)
Abstract
There is a growing concern in countries around the world, including Iran, about the effects of extreme climate change, diversification, and events on food production, food security, and livelihoods. The link between climate change and food security in the Iranian food system is the subject of this article. This review, based on the available literature, used the food system approach to achieve a broader view on issues related to food security in Iran. To this end, this study investigated climatic challenges facing food security in Iran with a focus on two essential products in Iranians’ food basket, namely, wheat and rice: Decreased agricultural productivity, food losses along production and distribution chains, postharvest loss, low resilience of poor people in rural areas, and the prevalence of malnutrition among children. The results showed that in addition to measures, such as making food production systems resistant to climate change and the necessary changes in existing food systems to adapt to the consequences of climate change, achieving food security requires a long-term vision to transform the Iranian food system. Accordingly, it is necessary to develop a climate-smart agriculture system that encompasses all aspects of food system security. Except for investigating the productivity of some essential components of this food basket, the results showed that there are scant studies on the effects of climate change on the food system of Iran.
Volume 25, Issue 1 (1-2023)
Abstract
Wheat is the main crop in the world. Tan spot caused by Pyrenophora tritici-repentis (Ptr) is a destructive disease in wheat-producing areas. Accumulation of phenolic acids at the onset of the fungal infection induces plant’s resistance to tan spot. This study evaluated the effect of phenolic compound accumulation on the resistance to tan spot in wheat–pathogen interactions. Five different wheat cultivars including Glenlea, Salamouni, Moghan 3, Morvarid, and Bolani were studied at three different time points after inoculation with Ptr. The composition and concentration of phenolic acid including ferulic acid, p-coumaric acids, vanillic acid, chlorogenic acid, and rutin were detected using high-performance liquid chromatography and analyzed according to standard curves. Results showed considerable accumulation of ferulic acid, p-coumaric acids, vanillic acid, chlorogenic acid, and rutin in treatment with Ptr during 7 days post-inoculation in resistant and partially resistant cultivars compared with the susceptible ones. Ferulic acid was the most abundant phenolic compound in Salamouni (16.77±0.16 mg g−1 dw), Moghan 3 (17.76±0.00 mg g−1 dw), and Morvarid (23.11±0.00 mg g−1 dw) at 7 dpi. The obtained data indicated that the identified phenolic acids had enhanced and improved the wheat resistance to the fungal pathogen. Linear Pearson’s coefficient analysis showed a positive correlation between some phenolic acids concentration and also between them and flavonoid rutin in wheat cultivars during infection. These findings highlighted the capacity of phenolic compounds as potential tools for the identification of resistance in wheat–pathogen interactions.
Volume 25, Issue 1 (Winter 2022)
Abstract
Background:
SARS-CoV-2 which first was observed in Wuhan region, China in December 2019 has affected many organs, such as central nervous system. We describe a case of a 57-year-old male patient, in the hospital with the loss of consciousness, in the form of lack of verbal and visual communication. He got a seizure attack for about 3 minutes in the form of generalized tonic-clonic seizure (GTS) and admitted to the neurological department and was intubated. Since, the patient was not aware, awake, did not obey, corneal reflexes test was positive and his pupils were isochoric and reactive therefore, the primary diagnosis was cerebrovascular accident (CVA). On the second day after admission, although the brain computed tomography (CT) did not show brain lesion, but the chest X-ray (CXR) revealed lung involvement. In addition, on third day the RT-PCR test for coronavirus RNA in and the cerebrospinal fluid and nasopharyngeal swap done and the result was positive for both of them. Therefore, treatment for the covid-19 was started.
Results:
Since, the treatment for the covid-19 was started with Atazanavir, Clindamycin and Ceftriaxone. Ten days after hospitalization, the lung involvement and general condition of patient got better and after two weeks he was released from the hospital.
Conclusion:
GTS should be considered as a neurological outcome of COVID-19 and medications against the coronavirus, such as Atazanavir, Clindamycin and ceftriaxone can recover the neurological deficits in these patients.
Volume 25, Issue 1 (3-2026)
Abstract
Abstract
Steel shear walls have been used in various buildings as a system to resist lateral loads. The special advantage of this type of wall is its good malleability, high initial hardness, and high energy consumption power. But due to its special geometry, the steel shear wall undergoes buckling in the elastic range. To prevent steel sheet buckling in steel shear walls, there are two general solutions: using metal stiffeners or using concrete cover that is connected to steel sheet through shears. Based on this research, a solution has been proposed to improve the seismic performance of modern steel-concrete composite shear walls. The composite steel shear wall is a modern lateral bearing system consisting of a steel sheet with a reinforced concrete cover, which is connected to the sheet from one side or both sides by clips. In the composite steel shear wall, the reinforced concrete cover, by restraining the steel sheet and preventing its buckling, increases the shear capacity of the steel shear wall to the point of yielding in shearing inside the plate instead of tension in the direction of the tensile field. The composite steel shear wall, while increasing the shear capacity of the system, increases the resistance of the panel against destructive factors such as corrosion, fire, impact, explosion, and other cases and causes a reduction of more than 25 to 50 percent in the consumption of steel in medium and large buildings. In the new composite steel shear wall system, a distance is created between the concrete cover and the boundary beams and columns. Tests on conventional and modern composite steel shear walls show that the modern system has little damage compared to the conventional system. From nonlinear static analysis using the finite element method and with the help of ABAQUS software, the influence of the geometric characteristics of steel stiffeners on the seismic performance of the modern steel-concrete composite shear wall has been investigated. After modeling the steel-concrete composite shear wall and validating the numerical model with laboratory results, the effect of parameters such as the number of stiffeners, the type of arrangement, including vertical, horizontal, diagonal, and combined, on the maximum bearing capacity of the composite shear wall, ductility coefficient, additional strength, energy consumption, compressive damage of the concrete hardener, and failure modes have been investigated. The results of this research show that the use of T-shaped steel stiffeners and their arrangement have a significant effect on the bearing capacity of steel-concrete composite shear walls and cause the overall buckling of the steel sheet to become local buckling between the stiffeners. The use of diagonal stiffeners increases the capacity of steel shear walls by 25%. The ductility factor and added strength factor of the steel frame with diagonal stiffeners are about 39 and 124% higher than the ductility factor and added strength factor of the base sample without the use of stiffeners, respectively. The use of diagonal stiffeners in composite shear walls compared to composite shear walls without steel stiffeners increases energy consumption by about 18%. The use of T-shaped steel diagonal stiffeners in composite shear walls compared to composite shear walls without steel stiffeners causes a significant reduction in the damage and failure of the concrete stiffener.
Amir Maleki, Alimohammad Javadi, Mohammad Javad Zahedi, Yaughoub Ahmadi,
Volume 25, Issue 2 (3-2018)
Volume 25, Issue 2 (3-2018)
Abstract
This study investigates political culture in the city of Tehran, focusing on three of its domains including typology of political culture, classification and typology of political citizens, as well as examination of some variables affecting political culture in Iran. The applied research method is in the form of a survey and questionnaire-based data. The study sample size includes 612 citizens residing in Tehran in 2018. Findings show that most citizens are tended to a subject- parochial political culture. It is indicated that political variables i.e. the cost of political activity, government officials’ responsiveness, and institutional political trust are effective on political culture. Using cluster method, the citizens were divided into four categories: critical, obedient, unmotivated, and disappointed. Political culture factors are categorized in three groups by analyzing exploratory factors. These are: pluralistic, value, and involvement -behavioral. Findings show that, citizens have been grown higher in pluralistic, and with value aspects, but are in a low level with behavioral aspect, and this factor could be effective on political culture's type.
Volume 25, Issue 2 (7-2019)
Abstract
A novel is an art of narrating incident or story that is considered to be one of the best and beautiful kinds of verse. The text's sociology attempts to make the reading in a profound and fundamental way and is not complete or cannot fulfill its existence until it is read. Sociological criticism is one of the new and effective methods in analyzing literary texts especially novels. Accordingly, this article seeks to use the descriptive-analytical method to read the text of “Al-Audah ela al-Manfa" (Return to the Exile), a novel by Abu al-Maati Abu al-Naja, and shows the social and ideological issues the Egyptian community lived in it. The purpose of selecting this novel was its importance in drawing the Egyptian society and expressing their suffering during the presence of foreigners in the country. The results indicate that the narrator knows middle Egyptian classes well because he spent his life there and describes a certain ideology that can be expressed through the structural unification of the novel. Therefore, there is a strong relationship between the elements of place and time as well as social groups and personality with the issues and problems posed in the novel.
Volume 25, Issue 2 (7-2019)
Abstract
The present study is aimed at determining the role of teachers' emotional intelligence components (composition class) in predicting the aspects of creativity (writing) among students. A descriptive-correlation method is adopted in the course of this study. The sample includes 291 students of the 10th grade as well as 10 composition teachers from the city of Qom in the academic year of 2018-2019. They were selected through multi-stage random cluster sampling and were evaluated by Torrance Test of Creativity and BarOn Emotional Intelligence Questionnaire. The results of correlation analysis and multivariate regression indicated that there is a meaningful relationship between teachers' interpersonal skills and innovation and the elaboration of creativity among students. Also, there is a meaningful relationship between teachers' stress management and flexibility, innovation and elaboration of the students. The results also indicated that teachers' interpersonal skills meaningfully predict innovation and expansion in students; their stress management meaningfully predicts flexibility and innovation in students; and their general mood meaningfully predicts the elaboration of students' creativity. The results of the present study support that the emotional intelligence components of teachers are significant to foster the aspects of students’ creativity. Therefore, holding Teacher Training Emotional Intelligence Course seems to be necessary.
Volume 25, Issue 2 (Summer 2021)
Abstract
Abstract
Introduction
Cities have become central to ensuring a sustainable future. Many Cities employ strategic spatial planning, a transformative and integrative public-sector-led activity, to create a coherent spatial development strategy in order to pursue sustainable development. Due to its encompassing, cross-sectoral qualities, urban planning science is expected to strengthen nature-related aspects of urban planning. This article is focused around a discussion of the nature of strategic spatial planning, as exemplified in the planning literature, and as an example, from Ardakan Municipality.
Method
This paper aims to develop a strategic plan for the Ardakan city and operational plan of the Ardakan Municipality of Fars province. The method of explaining the subject is descriptive-analytic and strategic planning. The analytical unit of Ardakan in Fars province, the statistical population of the study is urban civil engineering experts on the one hand (as a think tank workshop), and citizens of Ardakan city on the other hand. A total of 19 experts were selected by the targeted sampling method and 150 citizens were randomly selected and separate questionnaires were distributed among them. In different stages of strategic planning to operational planning (landscape development and project extraction), comparative analysis methods (analysis and comparison of the city per capita with neighboring cities (, Oregon vision, the formation of panels for extracting strategies and goals, SWOT analysis has been used.
Conclusion
The city's strategic plan includes the development of a 20-years vision based on those four five-year plans. The prospect of goals and the target of the wisdom are tailored to the outlook. Extracting strategies are in six areasof social and cultural, economic, environmental, urban and institutional, physical, spatial and tourism. The operational plan for the years 1402-1398 includes 44 plans corresponding to 10 projects with the proposed amount of 168,800,000,000 Rails.
Introduction
Cities have become central to ensuring a sustainable future. Many Cities employ strategic spatial planning, a transformative and integrative public-sector-led activity, to create a coherent spatial development strategy in order to pursue sustainable development. Due to its encompassing, cross-sectoral qualities, urban planning science is expected to strengthen nature-related aspects of urban planning. This article is focused around a discussion of the nature of strategic spatial planning, as exemplified in the planning literature, and as an example, from Ardakan Municipality.
Method
This paper aims to develop a strategic plan for the Ardakan city and operational plan of the Ardakan Municipality of Fars province. The method of explaining the subject is descriptive-analytic and strategic planning. The analytical unit of Ardakan in Fars province, the statistical population of the study is urban civil engineering experts on the one hand (as a think tank workshop), and citizens of Ardakan city on the other hand. A total of 19 experts were selected by the targeted sampling method and 150 citizens were randomly selected and separate questionnaires were distributed among them. In different stages of strategic planning to operational planning (landscape development and project extraction), comparative analysis methods (analysis and comparison of the city per capita with neighboring cities (, Oregon vision, the formation of panels for extracting strategies and goals, SWOT analysis has been used.
Conclusion
The city's strategic plan includes the development of a 20-years vision based on those four five-year plans. The prospect of goals and the target of the wisdom are tailored to the outlook. Extracting strategies are in six areasof social and cultural, economic, environmental, urban and institutional, physical, spatial and tourism. The operational plan for the years 1402-1398 includes 44 plans corresponding to 10 projects with the proposed amount of 168,800,000,000 Rails.
Volume 25, Issue 2 (2-2023)
Abstract
The rich diversity of Persian carpets is a symbol of different cultures and traditions in this country. To ensure sustainability of the Handmade Carpet Industry Knowledge and Innovation System (HCIKIS), attention should be paid to the transformative approach that pursues holistic transformation in the production and consumption systems. The present study aimed to identify Formal Transformation Institutions (FTIs), classify them into main categories, and analyze them based on the production step, approval date, institution type, and geographical area of approval. Based on the results, there were 316 Formal Institutions (FIs) in the Handmade Carpet Industry (HCI). By open coding, 372 concepts were extracted from 509 concepts derived from different FTIs. Based on the axial coding, the FIs were divided into six initial categories of “carpet authority”, “carpet sales and maintenance inside Iran”, “handmade carpet exports and imports”, “carpet production infrastructure”, “handmade carpet production”, and “sanitary-therapeutic category”. At the next step, the matrix of the main categories based on different production steps was drawn. Among the main categories, the highest frequency was related to the category of “carpet production infrastructure” and the subcategory of “financial supply of carpet”. Although there are many FIs that support production, carpet weavers, as the main people involved in production, have received minimum supports during their working years due to unawareness of supports and loan conditions.
Volume 25, Issue 2 (7-2025)
Abstract
Nanomaterials have been used in the recent years to improve rheological properties of the asphalt binders and increase mechanical properties of the asphalt mixtures. The high cost of producing nanomaterials is one of the major obstacles that has limited their application in road pavements. In this research, two methods of producing nanomaterials have been applied to produce nano hydrated lime (NHL). The first method was a mechanical process of milling hydrated lime with the application of a planetary ball mill. The second method was chemical processing of dissolving certain chemical materials (namely, calcium nitrate Ca(NO3)2, sodium hydroxide NaOH and sodium dodecyl sulfate SDS) into distilled water. The process resulted in the production of NHL solution that after drying in an oven resulted in NHL particles. The sizes of the NHL products were measured using two methods of Field Emission Scanning Electron Microscope (FE-SEM) and Dynamic Light Scattering (DLS). The size analysis was performed on NHL samples that were produced after different milling periods in the physical method; and, variation of the concentration of the solution, mainly calcium nitrate and SDS, in the chemical method. The average particle sizes in the physical method, after 6 hours of milling, were 211 nm, as measures in DLS and 114 nm as measured in FE-SEM. These in the chemical method, at concentration of 3 ml of calcium nitrate solution (Ca(NO3)2), were 379 and 124.615 nm respectively. With the chemical method, the nano particles were formed in the plate form with average thickness of 68.5 nm. In addition, X-ray diffraction (XRD) and X-ray fluorescence (XRF) analysis were performed in order to determine the composition of the produced nano materials. These indicated that with the physical method, a higher lime content material was produced. With the aim of assessing the effectiveness of the produced NHL materials to modify asphalt binders, a 60-70 and an 85-100 penetration grade were used and nano modified binders containing 2, 4 and 6% NHL were prepared and were tested under standard bitumen tests and viscosity determination. The results indicated that with adding NHL to the asphalt binders, penetration was reduced and softening point was increased. In addition, the temperature susceptibility of the modified binders were reduced too. Assessing the change of the viscosity of the NHL modified binders, it resulted that 4% NHL would provide the optimum conditions.
Narges Sardabi, Reza Biria, Ahmad Ameri Golestan,
Volume 25, Issue 3 (6-2018)
Volume 25, Issue 3 (6-2018)
Abstract
Transmission-based teacher education programs have mostly dominated the field of teaching English as a foreign language. Considering the prominent position of critical pedagogical principles in prospective teachers’ perceptions of their professional roles and responsibilities, there is a need for detailed investigations of teacher education programs informed by the tenets of critical pedagogy in prospective teachers’ professional identity. There has been a paucity of research that addresses the impact of such programs on prospective teachers’ professional identity in an EFL context; therefore, this study intends to address the gap. This qualitative study was conducted to examine the role of a critical-informed teacher education program in influencing prospective EFL teachers’ professional identity construction. Participants were 19 prospective teachers whose process of professional identity construction were analysed through reflective journals, class discussions, and semi-structured interviews before and after the program. Results of the study revealed three major shifts in prospective teachers’ professional identity: “from a student’s voice to a teacher’s voice”, “from an uncritical attitude to developing agency”, “from a narrow view of ELT to a broad view”. To foster critical ideas in EFL prospective teachers, the study recommends the use of dialogic discussions and written reflective tasks in teacher education programs.
Volume 25, Issue 3 (Fall 2021)
Abstract
According to the principle of Freedom of contract the parties to the contract can include their preferred condition in the contract. In this way the condition of the best effort to fulfill the obligations is one of the conditions that can be mentioned in the contract, according to which, the obligor will do his best to fulfill the obligation. Such a condition causes the obligor not to think only of relieving himself. Despite the frequent use of such a condition in US contracts, there is no consensus on its validity. In this legal system, Some lawyers do not accept the mentioned condition due to its generality and ambiguity and consider it invalid, and on the other hand, they consider it correct. Recently, in international documents such as Unidroit Principles of International Commercial Contracts and Principle of European Law Service Contract the condition of the best effort has been recognized and declared valid. In Iranian law, this condition is explicitly accepted in some laws, such as insurance laws and medical law. This article, using a descriptive-analytical method, after explaining the concept of the best effort condition, examines the position of this condition in the legal systems of Iran and the United States, as well as some international legal documents.
Volume 25, Issue 3 (5-2023)
Abstract
Asian sea bass (Lates calcarifer) an important marine species of high economic value and excellent meat quality, has suffered great losses due to disease in high-density aquaculture. The macroalgae, Gracilaria pygmaea, which include various bioactive compounds, may serve as an immunostimulant in the aquaculture industry. This study aimed to assess the effect of dietary fish meal replacement with Gracilaria pygmaea meal on immunity, activity of liver antioxidant enzymes, intestinal tissue, lysozyme gene activity, and IGF-I gene activity in Asian sea bass (Lates calcarifer). To this end, 120 individuals of Asian sea bass with an average weight of 28±0.5 g were divided into four treatments and three replicates and kept in 12 tanks (10 fish per 300-liter tank). Blends of soybean meal and fish meal were used as a Control diet (C). Experimental diets were prepared to substitute the fish meal with 3 (GL3), 6 (GL6), and 9% (GL9) of G. pygmaea in the basal diet. Fish were fed three times daily for six weeks. Dietary supplementation of G. pygmaea led to significantly increase in total immunoglobulin level compared to the control. The inclusion of G. pygmaea in the diet did not affect the antioxidant status of the fish. The histological analysis showed that fish of all groups exhibited normal morphology of anterior intestine and pyloric caeca. The obtained results showed that fish of GL9 and the control groups had the highest IGF-1 mRNA transcript abundance in the liver compared to the other groups. The changes of lysozyme expression noticed among the groups were statistically insignificant. Overall, the results obtained in this study indicated that dietary G. pygmaea did not cause adverse effects on immune status, antioxidant status, intestinal morphology, and lysozyme gene activity in Asian sea bass.
Ahmadreza Eghtesadi Roudi, Hengameh Asefi,
Volume 25, Issue 4 (7-2018)
Volume 25, Issue 4 (7-2018)
Abstract
With the shift of research attention from human malfunctioning to human optimal functioning in the workplace, job engagement which is regarded the opposite of job burnout has attracted researchers’ attention in organizational psychology. This exploratory study aimed to investigate the predictive role of emotional intelligence (EI) as a personal resource in determining levels of job engagement among Iranian English language teachers within job demands-resources model (JD-R). To this end, 442 English language teachers who were teaching in both public and private contexts were selected through non-probability convenience sampling and were surveyed regarding their demographic information, the perception of their levels of job engagement and emotional intelligence through a demographic questionnaire, the Utrecht Work Engagement Scale (UWES), and emotional intelligence scale. The results of hierarchical multiple regression analyses revealed that after controlling for the effect of demographic variables, there were significant positive predicting relationships between two emotional intelligence subscales of management of own emotions (MOE) and management of others’ emotions (MTE) and job engagement components of vigor, dedication, and absorption. The results imply that training teachers to improve their emotional intelligence can be a strategy to boost their job engagement.
Volume 25, Issue 4 (5-2023)
Abstract
Tuta absoluta (Meyrick) (Lep.: Gelechiidae) is a major pest of tomato crops that causes high yield losses. Currently, in most countries, T. absoluta management is mainly based on chemical control. Nonetheless, special emphasis is being placed on implementing environmentally safe strategies. Commercial formulations based on Bacillus thuringiensis may be a good alternative, as they have been used to control other insect pests successfully. The laboratory and greenhouse data presented in this work are evidence that B. thuringiensis is highly efficient in controlling T. absoluta. Moreover, the toxicity effect of three pesticides (Biolep, Abamectin, and Indoxacarb) was evaluated against the first and last instar larvae of T. absoluta. Results indicate that the Bt formulation has the highest efficacy compared to the chemical pesticides. Abamectin and Indoxacarb had low mortality effect on the first and last instars of T. absoluta. In conclusion, the Bt formulations are recommended as an effective, environmentally friendly, and safe biopesticide for controlling tomato leafminer.