inverse sampling design is generally considered to be appropriate technique when the population is divided into two subpopulations, one of which contains only few units. in this paper, we derive the horvitz-thompson estimator for the population mean under inverse sampling designs, where subpopulation sizes are known. we then introduce an alternative unbiased estimator, corresponding to post-str...

In order to find the most effective method to overcome seed dormancy in Teucrium chamaedrys  L. medicinal plant species the effect of some chemical and physical breaking methods including: cold stratification (5 °C), scarification with sandpaper, stratification with needle, concentrated sulfuric acid, gibberellic acid and combination of these methods were investigated. Treated seeds along with ...

The addition of storage capacity to district heating systems increases flexibility and expands the range usable heat sources. Despite their apparently simple nature, thermal energy (TES) tanks display a wide performances due different construction operation choices, as proven by numerous literature studies. However, most investigations focus on domestic-size few cubic metres or, other hand, ver...

1. From measurements at several weir pool sites along the turbid and freshwater BarwonDarling River, Australia, the development of persistent stratification (for periods of >5 days) was related to river discharge. For the sites examined, the required discharge to allow the development of persistent stratification was between 100 and 450 ML day during the hotter months. High discharge during the...

Population stratification remains an important issue in case-control studies of disease-marker association, even within populations considered to be genetically homogeneous. Campbell et al. (Nature Genetics 2005;37:868-872) illustrated this by showing that stratification induced a spurious association between the lactase gene (LCT) and tall/short status in a European American sample. Furthermor...

DNA methylation is an important epigenetic mechanism that has been linked to complex diseases and is of great interest to researchers as a potential link between genome, environment, and disease. As the scale of DNA methylation association studies approaches that of genome-wide association studies, issues such as population stratification will need to be addressed. It is well-documented that fa...

Mountain mahogany (Cercocarpus montanus Raf) is a useful reclamation species because it can occupy and improve poor soils. Literature regarding seed propagation of tbis species is var· ied and often contradictory, recommending stratification dura· tions of 14 to 90 days, and sulfuric acid scarification durations of none to 60 minutes. To assess variability in propagation require. ments among se...