These are notes from introductory survey lectures given at the Institute for Studies in Theoretical Physics and Mathematics (IPM), Teheran, in 2008 and 2010. We present the definition and the fundamental properties of Fomin-Zelevinsky’s cluster algebras. Then we introduce quiver representations and show how they can be used to construct cluster variables, which are the canonical generators of c...

in order to study the epidemiology of accidents in tehran city, the author has collected and analysed records of more than 25,000 accident cases for the period 1960-61 from all available sources such as newspaper rapportages,nine major hospitals of tehran, forensic medicine department of ministry of justice, vital statistics department of ministry of health, labors' insurance organization, etc....

rapid spread of venereal diseases in advanced countries has prompted the authors to undertake this study on venereal diseases in iran, a fast growing country, with a view to finding ways for dealing with these diseases. data available at the vd centre in teheran, the rapidly developing capital of iran, have been used for this preliminary study. a retrospective analysis of available data for the...

l'eau de pluie et l'eau courante de l'environnement de teheran a ete collecte pendant un an. les echantillions collectes ont ete concentres et seches sur un platean et leur radioactivite totale a ete mesuree par un computer g. m. 620. le stronsium 90 a ete aussi mesure par la separation de 1' y (en equibbre avec sr) utilisant du t. t. a (1'0-thenoyltrifluoroacton) gomne...