Clinical practice in physical and manual therapy is experiencing a paradigm shift from an experience- and authority-based model to a more evidence-based model. National Practice Guidelines (NPG) are ...examples of this shift towards research-based knowledge. This article discusses the five steps in the development of NPGs. These steps are illustrated by a discussion of development and content of two NPGs produced recently in the Netherlands for the treatment of patients with non-specific low back pain.
Towards cleaner solar PV de Wild-Scholten, Mariska; Alsema, Erik
Refocus (Oxford),
9/2004, Letnik:
5, Številka:
5
Journal Article
Recent studies give the impression of photovoltaics having considerable environmental impact. Looking closer at the data however, it is clear that these studies are based on photovoltaic systems of ...the late eighties, with only minor recalculations. Since the photovoltaic market has increased rapidly, a lot of progress has been made regarding the environmental profile of photovoltaics. In this article Mariska de Wild-Scholten and Erik Alsema report on the improvements already achieved, those expected in the near future and the issues that need to be tackled for the development of crystalline silicon photovoltaics. They focus the discussion on multicrystalline silicon solar cells, the technology with the largest market share at present.
A small, personal monitoring study was performed in a subpopulation (14 families) of a case-control study on the relationship between indoor nitrogen-dioxide exposure and respiratory diseases of ...schoolchildren. Mothers, schoolchildren and pre-schoolchildren were asked to carry duplicate Palmes diffusion tubes during one week. Simultaneously nitrogen-dioxide concentrations were measured in the kitchen, living room, bedroom, outdoors and--for a few participants--at school and at work. Information on time activity patterns was gathered by means of a self administered diary. Several models for estimating exposure were constructed and tested against measured exposure. The personal exposure of the participants could well be explained by models containing indoor concentrations. Models with time-weighted average concentrations did not explain personal exposure better than models containing indoor concentrations. A calculated time-weighted average exposure was found to underestimate measured personal exposure by an average 20%, probably because the average concentration in a location does not necessarily reflect the actual exposure in that location. Personal exposure of mothers and children was very similar and highly correlated, indicating that the personal exposure of the mother might be a reasonable estimate for the exposure of the child.
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