BACKGROUND The decision to start long-term tube-feeding in elderly people is complex. The process by which such decisions are made is not well understood. The authors examined the factors involved in the decision to start long-term tube-feeding in cognitively impaired older people from the perspective of the substitute decision-maker. METHODS A telephone survey was administered to the substit...

In a companion paper, we showed that weak and strong notions of substitutes in economies with discrete goods have different implications for auction theory and equilibrium theory. In contrast, for the divisible goods case with concave valuations, natural extensions of these concepts coincide. Concave substitute valuations are characterized by submodularity of the dual profit function over nonli...

aims: intensification of current environmental legislation leads to an increase wastewater treatment sludge volume. so reducing the sludge volume is considered as a strategy to improve and solve the problems of secondary pollution of sludge. dissolved air flotation (daf) as a substitute clarifier is used for separation of activated sludge liquid-solid phases. the aim of this study was to estima...