در این تحقیق سیتوکینین¬های مختلف بر سرعت ریزازدیادی اسطوخودوس بررسی شد. جداکشت های دو گره¬ای سترون شده از یک گیاه گلخانه¬ای یکساله در محیط کشت MS دارای هورمون¬های بنزیل آمینو پورین(BAP)،2-¬ ایزوپنتنیل آدنین (2ip) و کینتین (Kin) به تنهائی یا در ترکیب با یکدیگر کشت شد. نتایج حاصل نشان داد سرعت رشد ریز قلمه ها، تعداد گره¬ها و نو ساقه¬های حاصل از هر جدا کشت در محیط کشت به نوع و غلظت هورمون بستگی دا...

this study investigated the potential role of age in inductive and deductive grammar learning among iranian foreign language learners. the experimental population consisted of our randomly selected samples including two groups of children (with age of exposure to english within 8-13), and two groups of adults (with age of exposure to english within 11-13). thus, the comparison was between ch...

abstract since heubners (1985) pioneering study, there have been many studies on (mis) use/ non-use of articles by l2 learners from article-less and article languages. the present study investigated how persian l2 learners of english produce and interpret english definite descriptions and demonstrative descriptions. it was assumed that definite and demonstrative descriptions share the same cen...

the present paper offers a postcolonial reading of two of the best novels by v. s. naipaul – half a life and the mimic men – in five chapters. the focus of this research is on different notions of postcolonial criticism and their application on the two novels as discussed from homi bhabha’s and frantz fanons points of view. having introduced the life and literary career of v. s. naipaul in th...

heteropoly acids (hpa) and their salts have advantages as catalysts which make them both economically and environmentally attractive, strong br?nsted acidity, exhibiting fast reversible multi-electron redox transformations under rather mild conditions, very high solubility in polar solvents, fairly high thermal stability in the solid states, and efficient oxidizing ability, so that they are imp...

the aim of the present study was to investigate the frequency and the type of discourse markers used in the argumentative and expository writings of iranian efl learners and the differences between these text features in the two essay genres. the study also aimed at examining the influence of the use of discourse markers on the participants’ writing quality. to this end the discourse markers us...

abstract the following study, in the first place, attempted to examine the effect of less experienced teachers participation in experienced teachers classes on their own skills and teaching methodology, in the second place, attempted to find out the role of teachers training in students achievements. for this purpose, 21 efl teachers were selected according to available sampling in kish l...

since the 1960s the age effects on learning both first and second language have been explored by many linguists and applied linguists (e.g lennerberg, 1967; schachter, 1996; long, 1990) and the existence of critical period for language acquisition was found to be a common ground of all these studies. in spite of some common findings, some issues about the impacts of age on acquiring a second or...