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1. In this study, we examine how a 7-year period of expanding submerged stonewort (Chara spp.) vegetation during a shift from turbid to clear water in a shallow lake influenced individual growth and population size structure of perch (Perca fluviatilis). We expected that a shift from phytoplankton to macrophyte dominance and clear water would improve feeding conditions for perch during a critical

Utförlig beskrivning av hårdvara för datoriserad styrning och övervakning av installationer. Rapporten är av beskrivande karaktär främst för att det är svårt att jämföra olika fabrikats lösningar av samma funktion. Komplettering av R114:1980 med programvara

A method is described which can be used to calculate dynamic gear tooth force and bearing forces. The model includes elastic bearings. The gear mesh stiffness and the path of contact are determined using the deformations of the gears and the bearings. This gives contact outside the plane-of-action and a time-varying working pressure angle. In a numerical example it is found that the only important

We review a neck method to explore the cellular functions in multicellular system by application of the perforated patch-clamp technique to intact pancreatic islet of Langerhans. Using this approach, the integrity of the islet is preserved and intercellular communication via gap junctions and paracrine processes are maintained. 13 using low-resistance patch electrodes, rapid current responses can

Om pappersskulpturer av Hjördis Tegsell och Thomas Pupkiewicz

The MAKEDEP model is designed to produce the time series of atmospheric deposition and nutrient uptake and cycling needed by dynamic soil chemistry models such as SAFE. A range of new features were implemented in the MAKEDEP model including separate treatment of several tree compartments (e.g. root, stem, bark, branch, canopy) and variable nutrient content in the different compartments. The mo

Effects of different bioturbators on recruitment of several nuisance algae, Anaboena spp. (Cyanophyta), Microcystis spp. (Cyanophyta), and Gonvostomum semen (Raphidophyta), from sediment to water were studied in a long-term laboratory experiment. Natural sediment, where macrofauna larger than 1 mm had been removed, was added to 18 aquaria. To each of six aquaria, individuals of Asellus aquaticus (

Iohexol, a newly developed non-ionic contrast agent, has been recently documented as a reliable glomerular filtration marker. This study describes the age dependence of the single injection clearance of iohexol in a sample of healthy male volunteers ranging from 21 to 77 years of age. In parallel, renal plasma flow was studied by measuring the total clearance of p-amino hippuric acid administered

A ferricyanide mediated microbial biosensor for ethanol detection was prepared by surface modification of a glassy carbon electrode. The selectivity of the whole Gluconobacter oxydans cell biosensor for ethanol determination was greatly enhanced by the size exclusion effect of a cellulose acetate (CA) membrane. The use of a CA membrane increased the ethanol to glucose sensitivity ratio by a factor

The male rat urinary bladder belongs to those few structures where both the post- and preganglionic parasympathetic nerves are accessible for severance. In the present study the sensitivity to the parasympathomimetic drug methacholine of muscle strips of either denervated or decentralized bladders was examined in vitro. One week postoperatively denervated and decentralized bladders were sensitized

Weathering rates of base cations are crucial in critical load calculations and assessments of sustainable forestry. The weathering rate on a single site with detailed geological data can be modelled using the PROFILE model. For environmental assessments on a regional scale, the weathering rates for sites are scaled into regional maps. The step from sites to regional level requires focus on the spa

A new class of block codes with low state complexity of their conventional trellis representations called double zero-tail terminated convolutional codes (DZT codes) is introduced. It is shown that there exist DZT-codes meeting the Varshamov-Gilbert bound on the minimum distance and having asymptotically optimal state complexity. Two ways of constructing DZT-codes are considered. Examples of DZT-c

We analysed and compared the functioning of UV-B screening pigments in plants from marine, fresh water and terrestrial ecosystems, along the evolutionary line of cyanobacteria, unicellular algae, primitive multicellular algae, charophycean algae, lichens, mosses and higher plants, including amphibious macrophytes. Lichens were also included in the study. We were interested in the following key asp

In a cross-sectional study of diabetic patients diagnosed at or after 30 years, and with different stages of retinopathy, factors such as duration of diabetes, treatment mode, metabolic control, blood pressure, and clinical signs of nephropathy were examined. The different stages of retinopathy used were absence of retinopathy, simplex, and severe retinopathy. Patients with simplex and severe reti

Lyme borreliosis (LB) is the most common vector-borne disease in the northern hemisphere, and southern Sweden is a highly endemic area. In over 70% of the cases, LB is represented by the non-disseminated cutaneous form erythema migrans (EM). This thesis has its focus on EM from a primary health care perspective in southern Sweden, including aspects on epidemiology, the clinical picture, gender dif