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In 1994 and 1995, we investigated the relationship between stream morphology and water chemistry and levels of organochlorines (HCB, PCB, and DDT) in young-of-the-year brown trout (Salmo trutta) from 25 streams in southern Sweden. Contrary to earlier findings for lakes, we found a positive relationship between trophic status (total phosphorus) and uptake of persistent pollutants in stream biota (t

Generalist predators contribute to pest suppression in agroecosystems. Spider communities, which form a substantial fraction of the generalist predator fauna in arable land, are characterized by two functional groups: web-building and cursorial (non-web-building) species. We investigated the relative impact of these two functional groups on a common pest (Sitobion avenae, Aphididae) in wheat by co

Vascular smooth muscle contractile responses to neuropeptide Y, alpha,beta-methyleneATP and noradrenaline were studied in circular segments of isolated vessels with intact endothelium in vitro from 12 patients with diabetes mellitus type 2 (NIDDM) and 12 control subjects. The dilatory effect of acetylcholine was used to test the function of the endothelium. Subcutaneous arteries and veins (diamete

1. In models of size-structured predator-prey systems, the effects are evaluated of gape-size limited predation on prey population growth and density when predators are non-interacting, cannibalistic, interfering, and cannibalistic and interfering. 2. Predation from non-interacting predators markedly reduces prey density, compared with prey densities in the absence of predation. When density-depen

We here use knockin mutagenesis in the mouse to model the spectrum of acquired CEBPA mutations in human acute myeloid leukemia. We find that C-terminal C/EBP alpha mutations increase the proliferation of long-term hematopoietic stem cells (LT-HSCs) in a cell-intrinsic manner and override normal HSC homeostasis, leading to expansion of premalignant HSCs. However, such mutations impair myeloid progr

Possible causes of deaths of Oreochromis niloticus in Lake Chivero were examined in relation to changes in limnological conditions monitored over a 25-month period. The fish deaths coincided with the collapse of an algal bloom that had developed and builtup in the lake for 8 months. Chlorophyll a and dissolved oxygen increased to average concentrations of 42.4 mu g l(-1) and 10.9 mg l(-1) respecti

The increasing demand for detecting and quantifying the negative effects on natural habitats caused by anthropogenic activity has led to the development of impact assessment tools. Here, we propose a monitoring method based on the concept of developmental instability (DI) estimated from fluctuating asymmetry (FA) in bilateral morphological traits in a monoclonal strain. The use of monoclonal popul

Simulated and measured correlation and diversity performance for a couple of two-antenna concepts are presented. The results indicate that the three-dimensional isotropic incident field is a good reference case to evaluate diversity performance in a multi-antenna application.

The sexes' share in parental care and the social mating system in a marked population of the single-brooded Lesser Spotted Woodpecker Dendrocopos minor were studied in 17 woodpecker territories in southern Sweden during 10 years. The birds showed a very strong mate fidelity between years; the divorce rate was 3.4%. In monogamous pairs, the male provided more parental care than the female. The male

Pollution-induced community tolerance (PICT) was used to study effects of phenol on soil bacteria. Phenol was added to an agricultural soil in a microcosm experiment. The effects were studied for up to four months. Bacterial growth rates were estimated with the leucine incorporation technique. This technique was also used as detection method for PICT. Changes in community structure were studied us

N,N-Dimethylacrylamide is polymerized in the lyotropic surfactant system containing Aerosol-OT (AOT) and water. The polymerization is thermally initiated with AIBN, which allows a homogeneous initiation in this very viscous mixture. The starting mixture contains a lamellar liquid crystalline phase and an isotropic phase in equilibrium. After the polymerization, new phases develop which appear to h

For decades, accessibility to the physical housing environment for people with functional limitations has been of interest politically, professionally and for the users Guidelines and norms on accessible housing design have gradually been developed, however the built environment shows serious deficits when it comes to accessibility This study addresses development of a content valid cross Nordic v

As part of research into small group homes run by local authorities for those with severe mental illness the characteristics of the social environment was investigated. The ideal and real versions of the Community Oriented Program Environmental Scale (COPES) were administered to residents and staff of small group homes in a county in southern Sweden. Both these groups were also interviewed on thei

Data on exposure variability is an important remedy for designing and interpreting studies of occupational ergonomics. The present study aimed at retrieving the within- and between-subjects variance of several mechanical exposure parameters in a repeated, short-cycle task. Seven experienced operators repeatedly secured joints using two types of hand-held nutrunners. The joints were placed in three

Barley is an abundant crop in Europe, which makes its straw residues an interesting cellulose source for ethanol production. Steam pretreatment of the straw followed by enzymatic hydrolysis converts the cellulose to fermentable sugars. Prior to pretreatment the material is impregnated with a catalyst, for example, H2SO4, to enhance enzymatic digestibility of the pretreated straw. Different impregn

The multicopper oxidases (MCOs) couple the four-electron reduction of dioxygen to water with four one-electron oxidations of various substrates. Extensive spectroscopic studies have identified several intermediates in the MCO catalytic cycle, but they have not been able to settle the structures of three of the intermediates, viz. the native intermediate (NI), the peroxy intermediate (PI), and the

Commitment of hematopoietic progenitor cells to B-lymphoid cell fate has been suggested to coincide with the development of PAX5-expressing B220(+)CD19(+) pro-B cells. We have used a transgenic reporter mouse, expressing human CD25 under the control of the B-lineage-restricted Igll1 (lambda 5) promoter to investigate the lineage potential of early progenitor cells in the bone marrow. This strategy