abstract amino acids are building blocks of proteins, and play a vital role in living beings existence and their functionality. the interaction of these compounds with metal ions is of great importance to biochemists, and chemists, because their functions can be utilized as a model in understanding enzymes mechanism for transport of metal ions to tissues. among twenty essential amino acids w...

textbooks play a crucial role in language learning classrooms. the problem is that among the great quantity of available textbooks on the market which one is appropriate for a specific classroom and a group of learners. in order to evaluate elt textbooks, theorists and writers have offered different kinds of evaluative frameworks based on a number of principles and criteria. this study evaluate...

background: organic nitrates relax all kinds of smooth muscle , not only vascular smooth muscle , a fact that has allowed the use of these drugs to treat many different aliments. objective.-the purpuse of this study was to examine prosepectively benefical effects , if any, of sublingual nitroglycerin on the pain of renal colic. design.- prospective , randomised , double blind, placebo- contoled...

the present study sought to investigate the impact of using mind-mapping technique instruction on female elementary efl learners reading comprehension; it also investigated their attitudes towards using mind-mapping technique as a tool to improve their reading comprehension. this study followed a quasi-experimental design with two intact groups as experimental, and control groups. the participa...

the debate whether esp teachers need to have knowledge of the specialized field they are teaching has been an issue in the literature over the last two decades. the aim of conducting this study was to explore iranian learners’ and instructors’ beliefs and attitudes concerning the role of specialized knowledge in teaching esp classes. a seventeen item questionnaire was administered to 400 esp le...

as some definitions show, idioms are expressions whose meanings cannot be obtained from individual words. in every society, people use their own conceptions and feelings through different idioms and expressions. so every culture and society has their own idioms. some scholars proposed methods for translating idioms but baker’s strategies are very important and constructive. this research tried ...

plagiarism in esl/efl learning contexts has been established as a dynamic and multi-layered phenomenon and has become a topic engaging many researchers in a heated debate in recent years. comparisons of student-generated texts with their source texts have shown that students rely on source texts in their writings and copying is a major strategy used by both l1 and l2 writers. in our country a...

any change in the refractive index of a laser active medium can lead to serious degradation of beam quality, laser beam modes, laser performance and variation in the intensity distribution. alteration in the refractive index of laser active medium is especially notable in high power lasers. it is clear that in the laser beam production, the pumping agent induces a great amount of heat which...

until now many studies have been done over recent decades throughout the world to show the right age to start english. in iran, research is still at an early stage in terms of evaluating teachers’ beliefs about teaching children english. the problem of at what age to start teaching english and how to teach english to elementary school children has not been solved neither in this country nor els...

a novel and ultra low cost isfet electrode and measurement system was designed for isfet application and detection of hydronium, hydrazinium and potassium ions. also, a measuring setup containing appropriate circuits, suitable analyzer (advantech board), de noise reduction elements, cooling system and pc was used for controlling the isfet electrode and various characteristic measurements. the t...