this study was undertaken in order to ascertain the carrier rate of group a hemolytic streptococci in the throats of pupils in selected schools of tehran, and to evaluate the role of socio-economical factors on carrier state. during the period of six months, 7020 children and adolescents, aged 10 to 17, were studied. these pupils were visited at their schools and their socio-economical level wa...

undoubtedly, attempt to self-inflicted burning needs special conditions for special individuals. self-inflicted burn is highly depended on individual and social factors. this study is aimed at evaluating the burning percent, age, economical conditions, educational levels, occupation, and marital status of the self-inflicted burn females of taleghani hospital. this is a descriptive- sectional st...

Today, transportation is one of the substructure parts of society that not only affects the economical growth process, but also is changed in development. The transportation substructure is one of the substructure parts of services has an important position in the economical development of countries. An efficient and appropriate transportation network causes goods transportation and services co...

A number n is said to be economical if the prime power factori-sation of n can be written with no more digits than n itself. We show that under a plausible hypothesis, related to the twin prime conjecture, there are arbitrarily long sequences of consecutive economial numbers, and exhibit such a sequence of length 9.