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Popular Abstract in Swedish Kärnkraftverk släpper under drift ut små mängder av många olika radioaktiva ämnen. De flesta av dessa ämnen når aldrig människan. Detta beror vanligen på att de hunnit sönderfalla på vägen eller att det saknas upptagsvägar vilket betyder att de är otillgängliga för människan. Ett av undantagen är kol-14 (14C). Detta radioaktiva ämne produceras både naturligt och genom mThis thesis presents the results from studies on carbon-14 produced by nuclear power reactors. Radioactive 14C enters the carbon cycle and can be taken up by humans, where it will constitute a potential health hazard. Therefore, the main focus of this thesis was to provide new data and knowledge necessary for the implementation of appropriate nuclear waste management strategies. Such data have pre

Dual process models of recognition memory assume that memory retrieval can be based on two distinct processes: an assessment of a context-free feeling of familiarity or on the reinstatement of specific context attributes that have been bound together to form a representation of the study episode during encoding (recollection). Recent neurophysiological evidence suggests that familiarity and recoll

In metabolically engineered Saccharomyces cerevisiae expressing Pichia stipitis XYL1 and XYL2 genes, encoding xylose reductase (XR) and xylitol dehydrogenase (XDH), respectively, xylitol is excreted as the major product during anaerobic xylose fermentation and only low yields of ethanol are produced. This has been interpreted as a result of the dual cofactor dependence of XR and the exclusive use

The finite element method has been used to analyze three topologies of iron-powder electrically magnetized synchronous machines. The first topology has the field winding placed in magnetically conducting end-plates, eliminating the need of slip-rings. In the second topology this is achieved by placing the winding above the outer rotor, and the third topology corresponds to the more conventional de

This is the first record of a representative of the organic-walled dinoflagellate cyst genus Palynodinium from the New Zealand region. Previously, Palynodinium grallator has been reported from two sites in offshore Tasmania during Ocean Drilling Program, Leg 189. The new species Palynodinium minus is found consistently in latest Maastrichtian? and earliest Danian strata (latest Haumurianeearliest

Effective requirements engineering (RE) can support efficient development of successful products. However, assessing and improving how RE supports its context, i.e. the development life cycle, is non-trivial since many different roles and factors are involved over a long period of time. Project retrospectives may support project teams in reflecting on how requirements are agreed upon and communica

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Trains of ultrashort laser pulses have been used to generate and to coherently control acoustic phonons in bulk InSb. The coherent acoustic phonons have been probed via time-resolved x-ray diffraction. The authors show that phonons of a particular frequency can either be enhanced or canceled. They have carried out simulations to understand the size of the effects and the levels of cancellation. (c