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Volume 0, Issue 0 (Articles accepted at the time of publication 2024)
Abstract
The present study aimed to evaluate pragmatic skill of adult right and left hemispheres damaged Persian speaking patients using the Persian version of the Montreal Protocol for the Evaluation of Communication (M.E.C.). The statistical populations of the study were 10 adults, right and left hemispheres damaged Persian speaking patients due to cerebrovascular accident (CVA). Two sets of tests were used in the present study. The first ones were screening tests included Lateral Preference Inventory (Corn test), Mini Mental State Examination (MMSE) and Persian Diagnostic Aphasia Battery (EQ1). The Performance of patients in protocol subtests were evaluated and compared with each other individually, intragroup and intergroup. Data were analyzed using inferential statistical methods and no meaningful relations were found between them. These findings indicated that damage to the right and left hemispheres of the brain leads to pragmatic impairments. However, damages to the right hemisphere increases the severity of pragmatic impairments more than damages to the left hemisphere.
Volume 0, Issue 0 (Articles accepted at the time of publication 2024)
Abstract
The present research investigates the conceptualization of the metaphors of “fear” in the Quran. Conceptual metaphors are an important discourse in cognitive linguistics. In this approach, metaphors are believed to be a cognitive phenomenon which manifests in language. This research aims to identify the initial spheres based on which fear has been conceptualized in the Quran and endeavors to attain the stance of the Quran on this emotion. To this end, a body of 607 verses containing the concept of fear was collected. In the next stage, 18 concepts were identified using cognitive analysis. The two schemas of force and movement as the initial spheres play a major role in the conceptualization of “fear” in the Quran. In conceptualization based on movement, behavioral and physiological actions of people facing external forces indicate their lack of control and defeat by external forces, with a virtual basis in most cases. In return, in conceptualizing fear based on the schema of force, the presence of a range of forces such as pressure, blocking, and redirection in facing external forces express the voluntary reaction of people in overcoming the external forces. Hence, in line with its guiding purposes, the Quran has missioned the prophets, in many cases as a divine command, to ask His audience to confront the non-divine external forces with the force arising from – the fear – of divine majesty.
Volume 0, Issue 0 (Articles accepted at the time of publication 2024)
Abstract
In this article, “reduplication” is studied in Hawrami language. The data of the research is obtained in a fieldwork and in conversation with the speakers of a variety of Hawrami called "Hawrami-e Takht" (Hawrami of Takht), which is spoken in a number of villages in Sarvabad county of Kurdistan province in Iran. The main goal of the research is understanding functions of reduplication in Hawrami, and also to know the differences of functions of this phenomenon in that language in comparison to other Iranian languages, namely Persian. The analyses and studies of the research indicate that “complete” and “incomplete” reduplication in Hawrami have various manifestations, but complete reduplication of verbs seems special to Hawrami, and no parallel can be found for it in Persian. In addition, examination of some constructions resulting from incomplete reduplication in Hawrami, shows that inflectional sign of grammatical gender, which in its absolute form, appears in feminine gender, is lost or appears in a different way in the construction resulting from reduplication. Regarding some parts of the data and analyses of the research, it is possible to say that this research also confirms that reduplication has similar functions and mechanisms in human languages.
Volume 0, Issue 0 (Articles accepted at the time of publication 2024)
Abstract
This research examines the lexical processing of head-first endocentric compounds in Persian based on semantic transparency. This study shows whether the processing is related to the morpheme-based, whole-word, or dual-root models. Moreover, this research concludes whether the processing is associated with sublexical or supralexical models. Two separate masked priming tasks are conducted. In the first experiment, the compound word is the primed word and the modifier is the target. In the second experiment, the prime is the compound word and the target is the head. Three conditions are considered: transparent, opaque, and orthographic-overlap. In order to analyze the result, mixed models are used. The results show significant priming effects for transparent and opaque conditions. While no priming effect is shown for the orthographic-overlap condition. It can be concluded that the lexical processing of head-first endocentric compounds is independent of semantic transparency. The processing is morpheme-based and it is on the basis of the sublexical model. Furthermore, the semantic processing of these words is supralexical. Moreover, the lack of priming effect for the orthographic conditions is seemingly associated with orthographic complexity in the Persian writing system.
Volume 0, Issue 0 (Articles accepted at the time of publication 2024)
Abstract
The intricate connection between teacher support, academic burnout, grit, and psychological wellbeing is a compelling area of research that has recently garnered second language (L2) education researchers' attention. This study aims to investigate such complex relationships with undergraduate English-major students in Iran. To this end, a sample of 318 undergraduate English-major students from various universities in Iran was selected through convenience sampling. The data were analyzed using IBM SPSS version 26 for descriptive statistics and correlation analysis, while LISREL software was employed for Confirmatory Factor Analysis (CFA) to validate the measurement models. The findings revealed that teacher support showed a positive and significant correlation with students' L2 grit and L2 psychological wellbeing while demonstrating a negative and significant correlation with students' L2 academic burnout. Furthermore, the simple linear regression analysis indicated that teacher support significantly predicted a 13% increase in students' grit and psychological wellbeing and a 0.03% in academic burnout. This suggests that measures to reduce the academic burnout of students in higher education should be prioritized in second language education through positive teacher support and positive psychology. The study provides valuable insights and recommendations for English language teachers, students, and policymakers and outlines future research directions.
Volume 0, Issue 0 (Articles accepted at the time of publication 2024)
Abstract
This article explores the effect of iconicity and textual cohesion on processing causal relations in Persian discourse using an experimental method. A reading-time task with a within-subject design was set up. Twelve 3-sentence experimental scenarios and 12 filler scenarios were constructed. Iconicity and cohesion were the independent variables and participants’ reaction time (RT) was the dependent variable. The cohesion variable manipulated the degree of cohesion between the first and second sentences of scenarios. The iconicity variable manipulated the order of the second and third (cause and effect) sentences of scenarios. Forty-eight participants read the scenarios and verified if the target sentence, which asserted the implicit causal relation between the second and third sentences of scenarios, was correct. The RTs of the participants were collected using DMDX program. The data were then submitted to a mixed-model analysis in R. The main effect of iconicity and cohesion on participants’ RTs was found. There was no interaction effect between iconicity and cohesion. The target sentence had the shortest RT in the condition with iconic and high-cohesion scenarios. Also, the target sentence in the condition with iconic but low-cohesion scenarios was processed as fast as the target sentence in the condition with non-iconic but high-cohesion scenarios. The findings confirm the facilitatory effect of iconicity on understanding causal sequences. The results also show that if, for discourse reasons, information is provided non-iconically, the existence of highly cohesive relations between the causal sequences and the previous context can compensate the non-facilitatory effect of non-iconic sequences.
Volume 0, Issue 0 (Articles accepted at the time of publication 2024)
Abstract
Cet article examine l'approche de la mise en œuvre des compétences de compréhension de l'écrit dans les cours de langue française en Iran. Les données étudiées dans cette recherche ont été recueillies par le biais de questionnaires, d'entretiens et d'observations en classe. Les objectifs de cette étude sont de comprendre les perspectives et les opinions des apprenants et des enseignants concernant les compétences de compréhension de l'écrit, d'examiner les approches pédagogiques utilisées et d'identifier les obstacles existants dans ce domaine. En conséquence, des suggestions spécifiques pour améliorer l'approche pédagogique de la compréhension de l'écrit sont fournies. Les résultats de cette étude indiquent que les apprenants ont des compréhensions différentes de divers éléments liés à la compréhension de l'écrit, y compris la nécessité de lire rapidement pour accomplir les exercices, de passer du temps pour une compréhension approfondie des textes, etc. De plus, les réponses des enseignants soulignent l'importance de la flexibilité, de l'utilisation de ressources diversifiées et de l'implication active des apprenants. Les résultats obtenus de ces conclusions sont discutés pour l'enseignement de la langue française, mettant en évidence la nécessité de sensibiliser les apprenants et les enseignants à l'importance de la mise en œuvre de stratégies efficaces de compréhension de l'écrit.
Volume 0, Issue 0 (ARTICLES IN PRESS 2024)
Abstract
Volume 0, Issue 0 (ARTICLES IN PRESS 2024)
Abstract
The consumption of fresh fruit and vegetable is low and remains below recommended intake in Iran. The purpose of this study was to determine the predictors of consumers’ intention to consume fresh fruit and vegetable. This study investigated the relationship among attitude, subjective norm, perceived behavioral control, health involvement, subjective health, and Iranian consumption intention by using the Theory of Planned Behavior. The Partial Least Square-Structural Equation Modeling was applied to estimate the model. The results revealed that subjective health (β = 0.463; p < 0.001) as a self-rating of overall health was an important predictor of Iranian consumers’ intention to eat fresh fruit and vegetable. Consumers’ health involvement (β = 0.198; p < 0.001) that shows importance of health issues for individuals, had significant effect on consumption intention. Other variables such as subjective norms (β = 0.175; p < 0.001), positive attitude towards fresh fruit and vegetable consumption (β = 0.125; p < 0.01), and perceived behavioral control (β = 0.110; p < 0.001) were significant predictors of consumption intention, respectively. The results provide useful and important information about main determinants of consumption intention for policy-makers to create effective and well-functioning public health policies aimed at increasing the consumption of fresh fruit and vegetable. Providing useful information regarding the freshness, quality, and safety of fresh fruit and vegetable by awareness campaigns can positively influence the behavioral intention of Iranian consumers.
Volume 0, Issue 0 (in press 2024)
Abstract
Concrete slabs subjected to near-field explosion loading often fail in a brittle manner. Common failure types include spalling and scabbing. Brittle failure leads to an inflexible and brittle structural response, producing small and large fragments that can be extremely dangerous due to their high velocities. Therefore, designing concrete slabs for explosive loading requires methods that either prevent or mitigate brittle failures or transform them into ductile failures. This study validates numerical models using LS-DYNA finite element software and compares them with reputable research. Simulations of concrete slabs were conducted using conventional methods, reinforced concrete slabs with steel plates, reinforced concrete slabs with wire mesh, and ultra-high-performance concrete (UHPC) slabs. The analysis of five slab types under similar explosion loading reveals that UHPC slabs exhibit less deflection and damage compared to other types, while conventional concrete slabs experience greater deflection and damage. The optimal reduction in damage for reinforced concrete slabs occurs when a steel plate measuring 2 by 4.2 meters and 0.5 centimeters thick is applied to the backside. Additionally, using wire mesh dimensions 25% larger than the initial slab damage yields the best performance. A comparative analysis of explosion-induced damage across different slab types indicates that reinforced concrete slabs with a 0.5-centimeter thick steel plate exhibit the largest damage area (8m2); whereas UHPC slabs show no damage, resulting in the smallest damage area. Further investigations into the dynamic response of these slabs demonstrate that advanced materials and reinforcement techniques significantly enhance their resilience against explosive forces. This study emphasizes the importance of innovative design strategies in civil engineering, highlighting that the adoption of UHPC slab minimizes structural damage and improves safety in high-risk environments. These findings underscore the necessity of incorporating modern materials and methodologies in protective structure design, ensuring better performance and longevity under extreme loading conditions. A comparative analysis of various methods for strengthening concrete slabs using identical materials shows that UHPC slabs outperform others in reducing deflection and failure. This illustrates their exceptional ability to withstand explosive dynamic loads. However, the primary limitation of UHPC slabs is their high cost and complexity of implementation. Reinforcement with steel sheets has proven more effective than wire mesh in minimizing deflection. In models reinforced with 0.5 cm steel sheets, deflection was reduced by 50% compared to conventional concrete slabs. The slabs reinforced with wire mesh demonstrated a significant decrease in failure rates compared to conventional slabs, with reductions ranging from 75% to 80% across various reinforcement methods using the same materials. Conversely, some models reinforced with steel sheets exhibited increased failure rates. The findings indicate that, in most cases, slabs with greater flexibility, such as those reinforced with wire mesh, sustained less damage. This can be attributed to the enhanced flexibility and ductility of wire mesh-reinforced slabs compared to those reinforced with steel sheets.
Concrete slabs subjected to near-field explosion loading often fail in a brittle manner. Common failure types include spalling and scabbing. Brittle failure leads to an inflexible and brittle structural response, producing small and large fragments that can be extremely dangerous due to their high velocities. Therefore, designing concrete slabs for explosive loading requires methods that either prevent or mitigate brittle failures or transform them into ductile failures. This study validates numerical models using LS-DYNA finite element software and compares them with reputable research. Simulations of concrete slabs were conducted using conventional methods, reinforced concrete slabs with steel plates, reinforced concrete slabs with wire mesh, and ultra-high-performance concrete (UHPC) slabs. The analysis of five slab types under similar explosion loading reveals that UHPC slabs exhibit less deflection and damage compared to other types, while conventional concrete slabs experience greater deflection and damage. The optimal reduction in damage for reinforced concrete slabs occurs when a steel plate measuring 2 by 4.2 meters and 0.5 centimeters thick is applied to the backside. Additionally, using wire mesh dimensions 25% larger than the initial slab damage yields the best performance. A comparative analysis of explosion-induced damage across different slab types indicates that reinforced concrete slabs with a 0.5-centimeter thick steel plate exhibit the largest damage area (8m2); whereas UHPC slabs show no damage, resulting in the smallest damage area. Further investigations into the dynamic response of these slabs demonstrate that advanced materials and reinforcement techniques significantly enhance their resilience against explosive forces. This study emphasizes the importance of innovative design strategies in civil engineering, highlighting that the adoption of UHPC slab minimizes structural damage and improves safety in high-risk environments. These findings underscore the necessity of incorporating modern materials and methodologies in protective structure design, ensuring better performance and longevity under extreme loading conditions. A comparative analysis of various methods for strengthening concrete slabs using identical materials shows that UHPC slabs outperform others in reducing deflection and failure. This illustrates their exceptional ability to withstand explosive dynamic loads. However, the primary limitation of UHPC slabs is their high cost and complexity of implementation. Reinforcement with steel sheets has proven more effective than wire mesh in minimizing deflection. In models reinforced with 0.5 cm steel sheets, deflection was reduced by 50% compared to conventional concrete slabs. The slabs reinforced with wire mesh demonstrated a significant decrease in failure rates compared to conventional slabs, with reductions ranging from 75% to 80% across various reinforcement methods using the same materials. Conversely, some models reinforced with steel sheets exhibited increased failure rates. The findings indicate that, in most cases, slabs with greater flexibility, such as those reinforced with wire mesh, sustained less damage. This can be attributed to the enhanced flexibility and ductility of wire mesh-reinforced slabs compared to those reinforced with steel sheets.
Volume 0, Issue 0 (Articles accepted for Publication 2024)
Abstract
Aim and Introduction
Achieving sustained and long-term economic growth necessitates the optimal allocation and utilization of resources at the national level. This goal relies heavily on the existence of efficient financial markets, particularly well-functioning and extensive capital markets. Numerous macroeconomic variables can influence the level of risk associated with shareholder rights, corporate cash flows, and adjusted discount rates. Additionally, changes in economic conditions can alter both the quantity and nature of investment opportunities.
However, establishing a fixed and consistent relationship between macroeconomic variables and stock price indices remains challenging. The complex and dynamic nature of financial markets makes it difficult to identify a method that accurately reflects economic conditions and captures the most critical influencing variables. Therefore, this study employs machine learning models to identify the key macroeconomic factors affecting stock price indices.
Methodology
Feature selection is one of the most common and crucial techniques in data preprocessing and serves as an essential component of machine learning. This study employs feature selection models to identify the most relevant predictors of the stock price index. The models utilized include the random forest method and regularized linear regression. To examine the nature of the relationships between variables, the jointness method was applied. Additionally, the mutual information analysis was conducted to assess the influence of key variables over different decades, enabling a deeper understanding of how the impact of macroeconomic factors on stock prices has evolved over time.
Findings
The study analyzed the impact of selected macroeconomic variables on stock price indices, focusing on the Tehran Stock Exchange. The findings from the Random Forest (RF) and Regularized Linear Regression (RLR) models indicate that exchange rates, financial development, inflation, economic growth, trade openness, and global uncertainty significantly influence Iran’s stock price index. The results demonstrate that global uncertainty, interest rates, and trade openness exert negative effects on stock prices, whereas the other variables positively influence stock prices.
The jointness method was employed to analyze the relationships between these variables, further confirming their significance. Moreover, the Mutual Information method was used to examine how the influence of these key variables varied across different decades.
Discussion and Conclusion
Among the variables examined, exchange rates, financial development, inflation, economic growth, trade openness, and global uncertainty emerged as the most significant factors influencing Iran’s stock price index. This finding is not surprising, given Iran’s historical experience with significant exchange rate fluctuations and persistent inflationary pressures. Global uncertainty has consistently influenced domestic markets in Iran due to political and economic instability. Previous research has highlighted the complex relationship between exchange rate fluctuations and stock price indices (Ratanapakorn & Sharma, 2007). Scholars have argued that the relationship between stock prices and exchange rates can significantly affect monetary and fiscal policy, as a recessionary stock market can reduce overall demand and impact broader economic performance.
Extensive research has also investigated the relationship between inflation and stock prices, identifying inflation as a significant factor affecting stock indices
(Boudoukh & Richardson, 1993; Fama & Schwert, 1977; Jaffe & Mandelker, 1976) . While some studies have reported a positive correlation between inflation and stock prices, others have found a negative relationship.
Moreover, trade openness has been recognized as a key factor influencing stock market fluctuations. Open economies are more vulnerable to external shocks due to increased global risk-sharing among markets. Although some studies have not found conclusive evidence of a direct effect between trade openness and stock prices, trade openness remains one of the influential factors (Nickmansh, 2016).
Stock prices reflect the present value of future cash flows, which are subject to two main effects: cash flow changes driven by increased production and interest rates, which serve as a discount factor. Stock prices tend to decline when expected cash flows decrease or interest rates rise. The level of actual economic activity directly influences cash flows, as higher economic activity generally leads to increased cash flow. Among the various indicators used to predict commodity markets, real Gross Domestic Product (GDP) is considered the most comprehensive measure of economic activity (Yuhasin, 2011; Christopher et al., 2006).
mouseout="msoCommentHide('_com_1')" onmouseover="msoCommentShow('_anchor_1','_com_1')">Finally, global uncertainty plays a significant role in shaping the internal economic environment of countries, making it an important global macroeconomic variable that influences the performance of publicly traded companies on the stock exchange.
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Volume 1, Issue 1 (3-2012)
Abstract
Reproductive performance and life expectancy of the two-spotted spider mite (TSSM), Tetranychus urticae Koch were determined on seven eggplant cultivars (Isfahan, Dezful, Shend-Abad, Neishabour, Bandar-Abbas, Jahrom and Borazjan) at 25 ± 1°C, 60 ± 5% R.H. and a photoperiod of 16:8 (L:D) hours. The results revealed that the TSSM gross hatch rate varied from 59% on Bandar-Abbas to 83% on Dezful. The gross fecundity rate was 59.726, 31.430, 31.443, 14.461, 19.328, 16.035 and 20.560 eggs/female and the net fecundity rate was 25.804, 17.496, 15.139, 7.620, 5.931, 7.526 and 11.947 eggs/female on the above-mentioned cultivars, respectively. The highest and lowest value of the net fertility rate was 20.735 eggs/female on Isfahan and 3.495 eggs/female on Bandar-Abbas, respectively. Also, the gross fertility rate was the highest on Isfahan (47.994 eggs/female) and the lowest on Bandar-Abbas (11.390 eggs/female). The values of the mean eggs per day varied from 2.040 to 6.560 eggs/female, which was minimum on Neishabour and maximum on Isfahan. The life expectancy of one-day-old adults of the TSSM was estimated to be 7.550, 8.380, 5.820, 4.850, 5.440, 5.330 and 3.950 days on the above-mentioned cultivars, respectively. Comparison of the reproductive parameters of the TSSM on the examined cultivars revealed that Isfahan was the most susceptible cultivar and Neishabour was the most resistant cultivar to this pest. Using resistant host plants is one of the most important components of an integrated pest management program.
Volume 1, Issue 1 (3-2012)
Abstract
The cotton bollworm, Helicoverpa armigera (Hübner), which is known as one of the most important economic pests, can cause severe damage to different crops in Iran and many countries of the world. The effect of five maize hybrids: SC260, SC500, SC700, SC704 and DC370 on lysozyme activity in the hemolymph of sixth instar of H. armigera using lytic zone assay and its association with some fitness parameters of this pest was studied in growth chamber (25 ± 1˚C, 65 ± 5% RH and a photoperiod of 16:8 (L : D) h). Our results indicated that except on SC260, the frequency of high immune-activated larvae on the other maize hybrids was lower than that of low immune-activated larvae. The mean lysozyme concentration in H. armigera larval hemolymph was the highest on SC260 (0.096 ± 0.01 mg/ml) and lowest on DC370 (0.060 ± 0.007 mg/ml). The longest pupal period was on SC500 (12.00 ± 0.49 days) and the shortest was on SC700 (10.37 ± 0.19 days). Daily and total fecundities of H. armigera were the highest on DC370 (61.68 ± 9.85 and 196.89 ± 49.30 eggs, respectively) and lowest on SC260 (20.60 ± 5.88 and 52.71 ± 18.80, respectively). The results of this study can provide fundamental information for management of H. armigera on maize hybrids.
Volume 1, Issue 1 (3-2013)
Abstract
Aims: Drug users form the main HIV-affected group in Iran. About two-third of all the individuals affected by HIV in Iran are those who use drug through injection. The aim of this study is to determine the effect of health belief model (HBM) on prevention of HIV transmission among the opiate-dependent population in Zarandieh. Methods and Materials: This is a quasi-experimental intervention study carried out on 49 addicted men in Zarandieh. was collected using a questionnaire, based on HBM and the group completed the questionnaire. According to the pre-test, the educational intervention was designed and implemented. Three months after the intervention, the post-test was performed and analyzed using the primary questionnaire and χ2, T-test. Findings: The findings indicated that the mean scores of HBM Model constructs (self-efficacy, susceptibility, severity and benefit) increased significantly after intervention and the perceived barriers decreased (p< 0.001). Also, the history of HIV testing reported 8%before intervention, while the rate increased to 48.6% after intervention. Conclusions: This finding provides initial support for designing and implementation of health education program, based on the HBM on Preventing HIV transmission among Opiate-dependent population.
Volume 1, Issue 1 (3-2013)
Abstract
Aims: Most of the world population who is at work and production age does not have appropriate and regular physical activity for various reasons. Accordingly, the researchers tried to evaluate the effect of physical activity predictors of employees through the path analysis based on the Pender's Health Promotion Model (HPM). Methods and Materials: We conducted this study on 359 employees of the milk and milk powder production factories in Mashhad. A questionnaire consisted of items related to the structure of the Pender's Health Promotion Model (Perceived Benefits, Perceived Barriers, Prior Related Behavior, Perceived Self-Efficacy, Activity Related Affect, Personal Factors, Interpersonal Influences and Situational Influences) and the IPAQ standard questionnaire related to the physical activity were designed and applied in interviews as data collection instruments. Findings: One fourth of the employees had proper physical activity. Generally, structures of the Pender's Health Promotion Model predicted 34.8 % of the physical activity behavior variance. Regression analysis has shown that the predictability of Prior Related Behavior, Perceived Self-Efficacy, Personal Factors, Activity Related Affect and Interpersonal Influences are significant and Situational Influences are nearly significant. Prior Related Behavior (β = 0.45, P < 0.000) and Self-Efficacy (β = 0.17, PConclusions: The findings of the study revealed that HPM is efficient in identifying and predicting the physical activity behavior. This pattern can be used as a framework for planning and implementing educational interventions in order to improve the physical activity of the adult employees.
Volume 1, Issue 1 (3-2013)
Abstract
Prangos ferulacea (L.) Lindl. (Umbelliferae family) is a dominant species in the some partial of habitats in Zagros Mountains. According to ethno-botanical studies, this plant is one of the best range plants of Iran. Local ranchers collect green Prangos while it is toxic. They then dry the plant and use it to feed their livestock, especially in winter season. This research done to analyse the changes in the chemical composition of Pr. ferulacea with the effects of time, location and type of secondary metabolisms. Therefore, the ingredients and amounts of the essential oils of Prangos were studied during the growing and flowering stages (in both green/fresh and dried forms) to track such changes. The results showed that the amounts of terpinolene, β-phellandrene and bornyl acetate were decreased in the dried form, and some of the harmful components, such as α-pinene, β-pinene, myrcen and delta-3-carene, were absent, rendering the plant non-toxic. These results confirm the opinion of the ranchers. In the growing stage, the amount of coumarin was significantly less than in the flowering stage, which also supports the conduct of the local ranchers who gather the plants at the most appropriate time.
Volume 1, Issue 1 (12-2010)
Abstract
Multiple sclerosis (MS) is commonest demyelinating disease among young adults. It demonstrates neurological dysfunctions in females more than males. Gonadal hormones have essential roles in maturation and differentiation of neurons and glial cells in both genders. The role of some gonadal female hormones such as progesterone has been well characterized on demyelination and remyelination in animal models. The role of androgens on neural system development and myelin maturation were identified. We previously observed that castration decreases the brain resistance against demyelinating insults and also reduces the subsequent repair. As the optic nerves and chiasm demyelination shows the hallmark characteristic in MS, inducing demyelination in optic apparatus, we have tried to find whether the effects of elimination of male gonadal hormones using gonadectomy could show the same, more or less changes in patterns of demyelination and repair comparing demyelinated females? Thus, to evaluate these alternations castrated male and female rats were compared by using visual evoked potentials and histological assessments on 2,7,14, and 28 days post lysolecithine (LPC) injection. Interestingly, we observed demyelination was started 2 day post lesion (dpl), reached to a maximum level at 7 and 14 dpl and then it partially but significantly reversed on 28 dpl. Demyelination and subsequent repair processes in both gonadectomized and female groups were shown almost the same patterns temporarily and in quality. Elimination of gonadal androgens could cause the male animals to undergone the same shape of de/remyelination compared female ones. In conclusion, differences between male and female demyelination and remyelination are substantially depending on male gonadal androgens. This work could be useful for understanding of the effects of sex hormones on demyelinating diseases and could offer fundamental information for repairing therapies in Multiple Sclerosis.
Volume 1, Issue 1 (11-2009)
Abstract
This article, using a sociological perspective, attempts to understand the application of empirical methods in the Iranian-Islamic golden age, especially during 130-500 Hegri. It distinguishes different approaches to rational knowledge and laying emphasis on empirical science in the mentioned period. The theoretical framework of the present paper is the sociology of science, especially the interpretative sociology of science in the Weberian and Mertonian traditions. This framework provides the possibility of studying internal cultural factors, beyond cultural exchange and external transfer of scientific knowledge. The author, through studying the history of natural sciences and humanities at the Iranian-Islamic golden age, shows how applying empirical methodology of science to, for example, historical, geographical, and anthropological knowledge, have been influenced by the social interpretation of prophetic religion. In particular, it is indicated that the cultural elements of social belonging, equality and mutual understanding of Shoobieh ethics influenced the above mentioned areas of scientific endeavor.
Volume 1, Issue 1 (4-2014)
Abstract
Background and aims: The E2F family of transcription factors is encoded by at least eight genes, E2F1-8. These proteins are important targets of the retinoblastoma protein (RB) contributed in regulation of transcription, cell cycle and apoptosis. The aim of this study was to investigate the expression levels of E2F protein family including E2F1, E2F2, E2F7, E2F8 and RB1 in the lineage negative (Lin-) hematopoietic stem cells (HSCs) of young and aged black mice using Real Time RT-PCR and western blot techniques. Methods: Lin- HSCs of 4 young (7-10 weeks old) and 3 aged (76 weeks old ) mice have been isolated from their bone marrow cells using MACS column and after RNA extraction of culturing cells and cDNA preparation, samples were then analyzed by Real Time RT- PCR and western blot techniques. Results: The E2F7 and E2F8 expression levels of the Lin- HSCs of old mice were only the transcriptional factors significantly decreased when compared with young mice. In conclusion: It seems the functional roles of important E2F7 and E2F8 transcription factors in moderating potentially destructive activity of E2F1 and regulation of cell cycle have been diminished in Lin- HSCs of aged mice. Hence, the apoptotic activity of the E2F1 would affect to the most HSCs, reinforcing bone marrow to proliferate the HSCs in old mice. However, Real Time RT-PCR data showed that the expression level of the E2F1 in those cells was not increased significantly as expected. This is the first report in this regard and further investigation with more samples need to reconfirm these data.