Kato's theory on the construction of strongly continuous evolution systems associated with hyperbolic equations is applied to linear equation describing an age-structured population that subject time-dependent diffusion. The system used provide conditions for well-posedness corresponding quasilinear equation.

In this study, the effects of particle size distribution improvement and dense packing techniques on the 28- and 90-day compressive strengths of class G oil well cement have been investigated. It was observed that limited improvements in the particle size distribution of cement (regarding industrial possibilities) cannot result in a significant increase in 28- and 90-day compressive strengths. ...

background :impact of substance abuse on outcome of hospitalized patients with acute myocardial infarction (mi) is a frequent question. available studies show disagreements over its impact, thus we performed this study to find a clear answer.   methods : in a cross sectional study, 304 patients (include 152 consecutive opium dependents and equal number of independents) with acute mi admitted to...