to determine breath- holding spells (bhs) prevalence and risk factors in under 6- year- old children, we interviewed mothers of 400 children in a cross- sectional study in 5 health centers at south of tehran in autumn 1999. 33 children (8.25%) had history of bhs (male: 19, female: 14 25 cases were between 2-4 years old (mean: 40±17 months). seventy percent of cases (23) had onset of attacks aft...

Goldman, Joichi, and White proved a beautiful theorem showing that the falling factorial generating function for the rook numbers of a Ferrers board factors over the integers. Briggs and Remmel studied an analogue of rook placements where rows are replaced by sets of m rows called levels. They proved a version of the factorization theorem in that setting, but only for certain Ferrers boards. We...

abstract determining saturated hydraulic conductivity (ks) is one of the important soil characteristics that its estimation is important in soil and water studies. there are several methods for estimating ks in unsaturated conditions. these methods include the inversed-auger-hole method, the double-ring infiltrometer and the single-ring pressure infiltrometer. the measurement of ks by these met...

The water turbine must be specially designed according to the calculation of its energy potential, proportional height falling and discharge. This research is conducted study solution fluid engine that functions as a pico hydro turbine, namely centrifugal blower with simple construction, operating at low head, small discharge, easy installation operation price. used in this test already on mark...

Analytical solutions of the flow equation for infiltration offer an interesting tool for the hydrodynamic characterization of non-saturated soils by optimization of the hydraulic conductivity, Kfs, and the capillary sorptivity, So. However, the experimental conditions have to satisfy the governing assumptions. For falling head infiltration tests the initial water height, Ho, is a third unknown ...