A major goal for ecology and evolution is to understand how abiotic and biotic factors shape patterns of biological diversity. Here, we show that variation in establishment success of nonnative frogs and toads is primarily explained by variation in introduction pathways and climatic similarity between the native range and introduction locality, with minor contributions from phylogeny, species ecol

In this thesis, liquid-membrane-based methods for the analysis of trace metal species in samples of environmental and biological origin were developed. By incorporating extracting reagents in the membrane liquid, trace metal ions were selectively separated from humic-rich natural waters and urine samples, prior to their determination using various instrumental techniques. The extractions were perf

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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