abstract the present study deals with a comparison between reactive and pre-emptive focus-on-form in terms of application and efficiency. it was conducted in an intermediate english class in shahroud. 15 male learners participated in this research and their age ranged from 18 to 25. a course book, new interchange 3, and a complementary book were used. every session the learners gave lectures o...

this is an original study on the effect of a polyisobutylene – polydimethylsiloxane (pibpdms) block copolymer modifier used as an interfacial active agent on the dynamics behaviour of single newtonian drops suspended in a polyisobutylene (pib) newtonian matrix. the results were divided in two sections. the first part included the experiments carried out on the non-modified and 2% block cop...

for a given riemannian manifold (m,g),it is an interesting question to study the existence of a conformal diffemorphism (also called as a conformal transformation) f : m ! m such that the metric g? = fg has one of the following properties: (i)(m; g?) has constant scalar curvature. (ii)(m; g?) is an einstein manifold.

vocabulary as a major component of language learning has been the object of numerous studies each of which has its own contribution to the field. finding the best way of learning the words deeply and extensively is the common objective of most of those studies. however, one effective way for achieving this goal is somehow neglected in the field. using a variety of activities such as games can r...

Salinity is one of the factors limiting the growth and development of the plants that has a negative effect on morphological and physiological processes in plants and in order to reduce these adverse effects used to from growth regulators. In this study, the effect of hormone Salicylic acid (SA) at 3 levels (0, 1 and 2 mM) to relieve stress (NaCl Soluble at concentrations of 0, 50, 100 and 200 ...

Three different concentrations (10, 20 and 30 ppm) of the dry propolis and pollen extracts were applied in double distilled water. Biochemical and hematological parameters in blood of rainbow trout (Oncorhynchus mykiss) treated to various propolis and pollen concentrations (10, 20 and 30 ppm) for 96 h were determined.  Fish treated to 20 and 30 ppm of propolis extract presented significant incr...