we have two part in this thesis, at first: the interaction of native calf thymus dna (ct-dna) with two anthraquinones including quinizarin (1,4- dihydroxy anthraquinone) and danthron (1,8- dihydroxy anthraquinone) in a mixture of 0.04 m brittone-robinson buffer and 50% of ethanol were studied at physiological ph by uv-vis absorption, florescence, circular dichroism spectroscopic methods, viscos...

current studies in second language (l2) learning have revealed the positive role of corrective feedback (cf) in both oral and written forms in different language features. the present study was an attempt to investigate the effect of both direct and indirect written corrective feedback (wcf) on the use of grammatical collocations in l2 writing. the study also sought to examine whether the effec...

flow in natural river bends is a complex and turbulent phenomenon which affects the scour and sedimentations and causes an irregular bed topography on the bed. for the reason, the flow hydralics and the parameters which affect the flow to be studied and understand. in this study the effect of bed and wall roughness using the software fluent discussed in a sharp 90-degree flume bend with 40.3cm ...

the following question poped up: is there any relationship between iranian high school efl learners reading comprehension and listening comprehension? then the following null hypothesis (ho) was developed to the test the above, mentioned question. "there is no relationship between high school efl learners reading comprehension and listening comprehension. for nearly 16 weeks, the experimental g...

this study aimed at examining the effects of iranian efl learners’ anxiety, ambiguity tolerance, and gender on their preferences for corrective feedback (cf, henceforth). the effects were sought with regard to the necessity, frequency, and timing of cf, types of errors that need to be treated, types of cf, and choice of correctors. seventy-five iranian efl students, twenty-eight males and forty...

abstract this study evaluates the iranian pre-university english textbook in terms of needs, objectives, content, and methodology. the study was designed on the qualitative- quantitative survey basis using interviews and questionnaires, a researcher-made textbook evaluation checklist and a needs analysis questionnaire. the textbook evaluation questionnaire was used in this study to elicit the ...

why some learners are willing to communicate in english, concurrently others are not, has been an intensive investigation in l2 education. willingness to communicate (wtc) proposed as initiating to communicate while given a choice has recently played a crucial role in l2 learning. it was hypothesized that wtc would be associated with language learning orientations (llos) as well as social suppo...

this study aimed to investigate the effects of listening strategy training on iranian efl learners listening comprehension and use of such strategies. this work, employing an experimental methodology, was conducted among 60 adult efl learners from a language institute in isfahan, iran, as participants. the participants, who were selected based on the results of a placement test, were assigned t...

rested on sociocultural theory (sct), this study attempted to examine the effect of written corrective feedback (wcf) followed by producing written languaging on developing writing accuracy over new tasks. to this aim, two intact iranian efl classes at the low-intermediate level were randomly assigned to two experimental groups: direct (n = 25) and indirect (n = 25). both groups wrote on a numb...

the present study was concerned with exploring the frequency and linguistic focus of corrective feedback types given by novice and experienced female teachers working with young learners and compared it with those of elementary classes for adults. moreover, it aimed at measuring learners’ acknowledgement of teachers’ corrective feedback in the form of uptake in relation to linguistic coverage o...