in the first chapter we study the necessary background of structure of commutators of operators and show what the commutator of two operators on a separable hilbert space looks like. in the second chapter we study basic property of jb and jb-algebras, jc and jc-algebras. the purpose of this chapter is to describe derivations of reversible jc-algebras in term of derivations of b (h) which are we...

abstract the present study was conducted to examine the effect of proficiency on students interaction while carrying out the grammar-based task(s) in collaboration. in particular, the study examines whether the level of proficiency affects the learners’ focus of attention to grammatical and lexical features. the study takes a further step and examines whether there is any difference in the use...

saluk mount is selected for devonian biostratigraphy. this area located at southwest of bojnurd. in this study three sections are selected and two sections, chahar-borj and tabar sections with a thickness of 650 m, which consist mainly of calcareous sediments was studied in detailed but third section, qelli section, with a thickness of about 450m which consist mainly of sandstone and evaporates...

for any educational program to be successful, many factors work hand in hand. based on pervious efl studies, teachers and learners are the keys to gain achievement. granted the fact that explicit and implicit practice plays a key role in education, knowledge of it can help teachers facilitate students’ vocabulary learning. this study investigated to determine the contribution of explicit and i...

the present research study attempted to find out the extent to which two pre-task activities of “glossary of unknown vocabulary items” and “content related support” assisted efl language learners with their performance on listening comprehension questions across two different proficiency levels (low and high). data for this study were obtained from a total of 120 language learners, female and m...

abstract the purpose of this study was to find out the effect of applying the principles of group-dynamic assessment (g-da) on learning of conditional structures in english by iranian efl learners at the intermediate level, which according to the formal educational system in iran, includes students who are in their second year of studying in high schools of koohdasht city. this study was a qua...

this study was intended to analyze the listening tapescripts of the elementary and pre-intermediate levels of total english textbooks from the pragmatic dimension of language functions and speech acts in order to see whether the listening tasks are pragmatically informative or not. for this purpose, 8 conversations from the two books were selected randomly, and then, the two pragmatic models of...

1. to determine whether difference in birth body mass influenced growth performance in pipistrellus kuhlii we studied a total of 12 captive-born neonates. bats were assigned to two body mass groups: light birth body mass (lbw: 0.89 ± 0.05, n=8) and heavy birth body mass (hbw: 1.35 ± 0.08, n=4). heavier body mass at birth was associated with rapid postnatal growth (body mass and forearm length) ...

this thesis seeks to present a critical reading of virginia woolf’s mrs. dalloway and michael cunningham’s the hours in terms of an intertextual approach, concentrating on dialogic imagination, negativity, transposition and allusion. this study attempts to evaluate cunninghams perception of woolfs life and work by adopting kristevas conception of intertextuality and her consideration of the hou...

esl/efl books play a crucial role in shaping language learners worldview of gender roles in society. the present study investigated the status of sexism in two sets of efl textbooks, one developed by non-native iranian authors (ili series) and the other by native authors (top notch series). first, two books from each series was selected randomly. then, a quantitative analysis was carried out wi...