Showing 10 results for Aliakbari
Volume 0, Issue 0 (Articles accepted at the time of publication 2024)
Abstract
The current study identified EFL teachers' emotional experiences in technology-equipped classes from an appraisal theoretical framework (Frenzel, 2014). It further explored the underlying antecedents of the recognized emotions and sought instructors' suggestions for improving the current unpleasant feelings experienced. To this end, 10 EFL teachers took part in the study. Necessary data were collected through journalkeeping and semi-structured interviews. The obtained data were analyzed using Merriam's (2009) inductive approach. Research findings revealed that teachers enjoyed the class as a result of students' achievement, positive interactions among learners, and pupils' active involvement. Moreover, they felt proud if they received positive feedback from students, observed progress in students' learning, and felt capable of instructing the learners. Furthermore, shame was experienced because of feeling unable to work with technical tools, strong filtration on educational websites, and not having internet-connected systems in class. Anger was also reported to be felt if they had to work with obsolete or impaired devices. Finally, teachers' pity was aroused as they perceived the lack of professional technical tools as detrimental to students' learning. They also mentioned that they felt compassion for learners as they cannot take part in CBTs and have limitations accessing e-sources online. Teachers also argued that unpleasant emotions could be minimized through investing in equipping classes, holding training courses, and establishing a criterion for teaching evaluation. In the end, the implications and limitations of the study are discussed.
Volume 2, Issue 2 (Summer 2018)
Abstract
In this study, three different size (100-300-500 µm) of the rubber powder (waste tire) were used in the formulation of epoxy- phenolic adhesive. Rubber powder was modified with grafting method by acrylamide monomer. In order to prevent any loss in properties such as modulus and strength of the adhesive, which is due to the addition of rubber powder to the adhesive, the micro particles of silica were used in formulation of epoxy- phenolic adhesive. The experiment was designed by Taguchi method, and in the experiment, the effect of the composition of rubber powder, size of rubber powder, composition of silica filler and phenolic resin on mechanical and thermal properties of epoxy adhesives were investigated. To study the mechanical properties of adhesives and adhesion properties, dumbbell-shaped specimens and single edge lap bonds that have been made of metal (stainless steel) to composite (epoxy resin / carbon fiber) were prepared and subjected to tensile test. Thermal stability and interfacial interaction between epoxy and filler in adhesive formulation were explored by thermogravimetric analysis and Fourier transform infrared spectroscopy analyses, respectively. Tensile test results showed that for lap- joint bonding with the addition of each factor in its optimal level into epoxy adhesive, strength, modulus and toughness increase by 7.5%, 27.56% and 114% respectively in comparison with the samples bonded with the neat epoxy adhesive. A significant increase was obtained in thermal stability for formulated adhesive samples compared with neat epoxy adhesive.
Volume 3, Issue 3 (Fall 2019)
Abstract
The aim of this project is the design and optimization of the formulation of epoxy adhesives for bonding metal to composite parts . This joints are most widely used in the aerospace industry to reduce stress concentration at a point. Joints for single edge joining include stainless steel metal with commercial code 316L and composite epoxy resin / carbon fiber. In this study, the effect of three types of additives: filler (alumina micro-particles), nylon 6.6 and phenolic resin (type of resin) on the mechanical and thermal properties of epoxy adhesive have been investigated. Tensile test results showed that increasing alumina fillers increases the tensile strength and overlap shear adhesive samples, respectively, in single lap joint dumbbells and elderly. The test showed that increasing the amount of nylon 6.6 When is slightly higher due to a sharp drop in tensile strength and overlap shear, respectively, in both cases is dog bone and single lap joint adhesives. This limit depends on the capacity epoxy ring to absorb amide hydrogens. The test for thermal properties (TGA) showed that increasing the amount of phenolic thermal stability is improved. High-temperature tensile test of appropriateness is also increasing impact of phenolic resin. Finally, the adhesive properties built with the similar adhesive (UHU) were compared. Results showed superiority in single lap joint metal to composite adhesive is made in the study.
Volume 5, Issue 7 (9-2020)
Abstract
This article according to the American School of Comparative Literature is addressed to the content similarities of the poems of Ali Reza Qazveh (born 1963) and Samih Al-Qasem (1939-2014), two contemporary Iranian and Palestinian poets in three areas of love; protestation and satire. It shows that in spite of the differences in the views of these two poets, due to the experience of similar situations such as the involvement of their homeland in war and some of its sufferings, their view of love, protestation and satire is remarkable and thought-provoking; As this view in love changes to the transformation of the beloved of lyrical poetry to the beloved who is a martyr and a fighter; in protestation, he inclines to his own protestation and fellowmen, and at a higher level, to human rights organizations. And in satire, he uses biting and deep satire on three levels of vocabulary, sentence or clause , and the generality of the poetry.
Volume 12, Issue 2 (Number 2 - 2010)
Abstract
Deoxynivalenol contamination was determined in corn produced in Golestan and Ardabil (Moqan) Provinces, Iran, in 2004-2005. Samples were collected from different stages of production, including before harvest, at harvest, post harvest as well as after drying. Ground sub samples were extracted with water; each extracted sample was cleaned up through an immunoaffinity column. Deoxynivalenol was estimated through reversed-phase High Performance Liquid Chromatography (HPLC). The linearity of standard curve for 50 -10,000 ng ml-1 of standard solutions was proved (R2= 0.9999). Detection limit was 10 ng g-1. Recovery of the method for 1,000 and 500 ng g-1 spiked samples was 73.5% and 93.5% (n= 5). Deoxynivalenol contamination was found in 76.7% of samples in the range of 54.4-518.4 ng g-1. The mean of contamination was 116.25 ng g-1. This is the first report of natural DON contamination of corn from Iran.
Dina Morshedi, Farhang Aliakbari,
Volume 15, Issue 1 (4-2012)
Abstract
Objective: Alpha-synuclein is a major component of protein plaques in synucleinopathies, particularly Parkinson’s disease. The purpose of this study is to assess the inhibitory effects of cuminaldehyde on the fibrillation of alpha-synuclein.
Methods: Alpha-synuclein was expressed in Escherichia coli and subsequently purified. For the process of fibrillation, purified protein was incubated at 37◦C and pH 7.2. Fibrillation was analyzed by the standard fibril methods. The effects of different concentrations of cuminaldehyde (20-500 μM) on alpha-synuclein fibrillation were studied by assessment of the cytotoxic effects of samples on the neuroblastoma cell line, SK-N-MC. To study the protein aggregation forms that were generated in the presence of cuminaldehyde, SDS resistance and induced fibrillation (seeding) methods were employed. For studying its specificity on alpha-synuclein, the effect of cuminaldehyde on lysozyme fibrillation was also examined.
Results: We showed, for the first time, that cuminaldehyde inhibited fibrillation by more than 80%. The highest inhibition was observed at the ratio of 5-15 moles of drug to protein. The viability of the treated cells with inhibited proteins was more than 90%, whereas non-inhibited samples caused a decrease in viability by 50%. Inhibited samples were not resistant to SDS and they were unable to induce fibrillation. Cuminaldehyde did not inhibit lysozyme fibrillation.
Conclusion: Cuminaldehyde inhibited fibrillation of alpha-synuclein which was accompanied by small amorphous aggregated particles of alpha synuclein. The inhibited protein samples did not induce aggregation. Thus, cuminaldehyde can be considered as a candidate to inhibit the formation of alpha-synuclein plaques.
Volume 15, Issue 81 (11-2018)
Abstract
Ketchup is highly consumed productand hydrocolloids are used as stabilizers in its formulation. In this study, native hydrocolloids of tragacanth gum and sage seed gum were used at levels of 0.5, 0.75 and 1% in ketchup formulation. Two ketchup samples without gum and commercial ketchup were considered as controls. The physicochemical, rheological and sensory properties of the samples were evaluated. Based on the results, samples containing tragacanth gum and sage seed gum had less pH and higher brix thancontrol without gum (p<0.05). The dry matter was decreased by increasing gum concentrations of 0.75 to 1 % and syneresis of ketchup samples was also decreased by addition of native gums and increasing their concentrations (p<0.05). Samples containing higher percentages of native gums and also commercial ketchup had higher brightness (p<0.05). Indeed the color quality of most of the samples were close to the commercial ketchup. In flow measurements, all samples showed pseudoplastic behavior and the 1% of sage seed gum created a zero shear viscosity higher than commercial ketchup (p<0.05).The viscoelastic solid behavior was observed in samples in viscoelastic test and most of the samples had appropriaterheological properties. No significant difference was revealed in the sensory characteristics between samples containing native gums and commercial ketchup. (p>0.05). The results of this study showed that ketchup with proper quality can be produced by using tragacanth and sage seed gum that it can be competitive withcommercial ketchup especially at higher concentrations.
Volume 18, Issue 1 (Spring 2018 2018)
Abstract
Inequality is a major problem in the developing countries. It is also an acute and critical subject in Iran compared with other developing economies. Besides the existence of inequality, its social effects have made its explanation crucial. The aim of this research is to measure the multidimensional inequality in urban areas of Iran during three presidential periods: 1989 -1997, 1997-2005 and 2005-2013. Income, health and education are the dimensions under study. This research uses household expenditure-income survey data for the selected periods. Gini coefficient is measured for one-dimensional inequalities in terms of each dimension, generalized entropy is computed for the beginning and ending years of each period, and the multidimensional inequality is measured by using the Bourguignon index. Results indicate that the Gini coefficient decreased in terms of income dimension in all three periods while it increased in terms of health dimension during all periods. In education dimension, Gini index increased in the second period and decreased in other periods. The measured entropy indices are of some fluctuations in all periods for all dimensions. The measured multidimensional inequality index provides a wide range of results for different substitution and inequality aversion parameters. In general, this index indicates worse conditions in the second period compared with other periods.
Volume 22, Issue 10 (October 2022)
Abstract
Parallel robots, which have several advantages over serial robots, have been one of the important industrial developments to increase the efficiency of controllable devices. Parallel structures have more suitable features such as higher rigidity, higher movement speed, non-cumulative errors and flexibility of the end-effecter pose. However, the workspace of parallel robots, compared to serial robots, faces limitations due to the existence of multiple kinematic chains, as well as the complexities related to robot control. Small size of workspace is one of the main challenges of parallel robots. Designing moving platform of a parallel robot is of the factors affecting the workspace of the robot. C4 is a four-dof parallel robot that is developed based on the three-dof Delta robot. In current study, the influence of the moving platform design on the workspace and efficiency of the robot has been investigated. After the initial overall design of the robot, three proposed modes for the moving platform have been investigated by considering the robot's kinematic parameters and robot error analysis. According to the results of the workspace and the robot efficiency analyses, the most efficient design has been selected.
Volume 23, Issue 1 (Spring 2023 2023)
Abstract
Aim and Introduction
The poverty is not affected only by income level. Some variables such as lack of access to welfare and health facilities, deprivation of education, physical weakness and vulnerability to diseases can be influential factors in poverty. Accordingly, indexes such as the poverty line, the percentage of poor people, and the intensity of poverty, which are used to study of the poverty in the society, do not fully represent the situation of poverty dimensions. Therefore, for measuring poverty in different dimensions, Oxford Poverty and Human Development Initiative in collaboration with United Nations Development Programme introduced the Multidimensional Poverty Index in 2010. This index includes deprivations such as low levels of health, lack of education, inadequate living standards, disability, low quality work, threats of violence, and living in areas with hazardous environments that poor people face in their daily lives. Several researches have been conducted on multidimensional poverty at the national and international levels, which have estimated the multidimensional poverty index using the Alkire-Foster methodological framework. At the same time, the multidimensional poverty of children has been neglected at the national level. This paper aims to study of multidimensional poverty among Iranian children based on the Alkire-Foster methodological framework. The multidimensional poverty of under five children using Multiple Indicator Demographic and Health Survey data in four dimensions of "living standards", "health", "support" and "development" has been measured.
Methodology
The Alkire-Foster methodology has been used for measuring the multidimensional poverty index. For measuring the children multidimensional poverty index (MPI) in Iran, data of the Multiple Indicator Demographic and Health Survey has been used. This survey covers the latest available data on various sociodemographic and health subjects of children, women and men. A comprehensive and new framework for measuring child poverty in Iran has been provided using the indicators of child mortality, cooking fuel, drinking water, sanitation discharge and housing from the global framework. The other indicators such as vaccination index and insufficient care has been extracted from other researches.
Findings
The results show that MPI of children in Iran is equal to 0.002. The incidence of multidimensional poverty is 0.5% and the intensity of child poverty is 38.6%. In general, the results show that girls compared to boys experience more multidimensional poverty and as mothers' education levels increase, children experience less multidimensional poverty. Children who live in large households (5 people or more) experience more multidimensional poverty compared to children who live in small households. Children in developed provinces experience multidimensional poverty less than other children and finally, children under five in the first economic quintile (the lowest economic level of the society) have the highest multidimensional poverty among all households in Iran.
Among children under five whose mothers have primary education, "health" dimension plays the most important role in measuring the multidimensional poverty index. In less developed provinces, the most important factor in mesearunig multidimensional poverty among children under five is "child development" dimension. Also, in households that have a low level of economic and social status (based on economic quintile variable), “child development " and "living standards” are important respectively.
Discussion and Conclusion
The purpose of presenting the Child multidimensional poverty index is to provide understandable and important statistics for clarify level and form of multidimensional poverty. The findings of this study, which was conducted for the first time in Iran, show that although value of the child multidimensional poverty index based on "living standards”, "health", "support" and "child development" is not a large number, however children in social and demographic groups have had encounters with different levels of multidimensional poverty. Considering that the growth and development of the children in the appropriate context is the basis for formation of a healthy and stable family and developed society, it is necessary to make policies in order to reduce the multidimensional poverty of children.