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Background: Anzali wetland has been subjected to high levels of pollution due to contamination from several industrial sites in addition to agricultural chemicals. Mussels have been widely used for monitoring pollution in aquatic ecosystems, because they, as filter feeders, bioaccumulate pollutants. Therefore we decided to evaluate Anodonta cygnea for its application as a bio-monitor for copp...
Water and sediment samples were collected from six different stations, located along the Nil River between February and June 2015. Concentrations of cadmium, lead, zinc, and copper were determined. The extent of the sediment pollution was assessed, using the multiple pollution indices, namely contamination factor (CF), pollution load index (PLI), and the geoaccumulation index (Igeo). The result...
the present study sought to investigate the role of dynamic assessment (da) in improvement of iranian efl writing performance at different language proficiency levels. to this end, after conducting the quick placement test, 60 iranian efl learners were assigned to two groups with different language proficiency levels. in both groups each participant wrote two compositions, one before and one af...
the present study investigated construct equivalence of multiple choice (mc) and constructed response (cr) item types across stem and content equivalent mc and cr items (item type ‘a’), non-stem-equivalent but content equivalent mc and cr items (item type ‘b’), and non-stem and non-content equivalent mc and cr items (item type ‘c’). one hundred seventy english-major undergraduates completed mc ...
this study investigated the functions, types and frequencies of code switching in the teachers and students discourse in elt classrooms. to this end, the participants of this study including two groups of teachers and students were selected. the first group of participants were two efl teachers teaching general english courses (at two different levels of proficiency) in an institutional program...
recent studies in scientific education as well as foreign and second language instruction suggest that thinking has rarely been an integral part of education and training in classroom. some scholars decried the lack of emphasis on thinking in the institutes and schools. they noted that memorization and drills were rewarded,while inquiry, reflection, and consideration of alternatives were frowne...
abstract: about 60% of total premium of insurance industry is pertained?to life policies in the world; while the life insurance total premium in iran is less than 6% of total premium in insurance industry in 2008 (sigma, no 3/2009). among the reasons that discourage the life insurance industry is the problem of adverse selection. adverse selection theory describes a situation where the inf...
Water and sediment samples were collected from six different stations, located along the Nil River between February and June 2015. Concentrations of cadmium, lead, zinc, and copper were determined. The extent of the sediment pollution was assessed, using the multiple pollution indices, namely contamination factor (CF), pollution load index (PLI), and the geoaccumulation index (Igeo). The result...
abstract the present study investigated the effects of task types and involvement load hypothesis on incidental learning of 10 target words (tws) in junior high schools (jhss) in givi, ardabil. the tasks deployed in this study were two input-based tasks (reading plus dictionary use with an involvement index of 3, and reading plus gap-fill task with an involvement index of 2), and one output-ba...
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...
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