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Phosphorus Release by Fish in Relation to External and Internal Load in a Eutrophic Lake

The aim of this study was to compare the rate of phosphorus release from fish with estimates of external and internal load in the eutrophic Finjasjon, Sweden. Phosphorus release from roach and bream, when fed either benthic (Chironomidae) or pelagic (Daphnia) prey, was measured in laboratory tanks. These results were transformed to whole lake conditions by using calculated fish consumption rates o

Bosonic realizations of the colour Heisenberg Lie algebra

We describe realizations of the colour analogue of the Heisenberg Lie algebra by power series in non-commuting indeterminates satisfying Heisenberg's canonical commutation relations of quantum mechanics. The obtained formulas are used to construct new operator representations of the colour Heisenberg Lie algebra. These representations are shown to be closely connected with some combinatorial ident

Digital reglering av klimatprocesser

Behovet av klimatreglering har ökat kraftigt sedan 1960-talet. Ett av skälen till detta är den ändrade byggtekníken, som innebär lättare konstruktioner med större inre värmebelastning från belysning, maskiner, personer och solinstrålning genom stora fönsterytor. De ökade värmebelastningarna kan klaras av med ett flertal olika klimatsystem. Dessa system kräver någon form av reglering. Under 1970-taResults from a research project supported by the Swedish Council for Building Research are reported. The main task was to improve climate control technology. The work was focused on digital control. It was split up into three main tasks: model building, design of regulators, and fullscale experiments. Several rooms, airducts, and heat exchangers were modelled. Simple dynamic models have been deriv

Genuine effects of ventricular fibrillation upon myocardial blood flow, metabolism and catecholamines in patients with aortic stenosis

Objective-Ventricular fibrillation (VF) is life-threatening because of its haemodynamic and metabolic effects. The purpose was to examine if VF also has primary effects per se. We therefore investigated the early effects of VF on myocardial blood flow, metabolic characteristics and catecholamine concentrations in patients undergoing surgery for aortic stenosis. Design-The immediate effects of up t

Xenotransplantation public perceptions: rather cells than organs.

The aim of this study was to describe some of the factors that might play a role in influencing attitude to xenotransplantation: first, the consideration of receiving cells and tissue from xenotransplants in relation to whole xeno-organs; secondly, the fact that there is greater uncertainty regarding the result and risk of infection associated with xenotransplantation than with allotransplantation

Working class culture in a time of change: Reflections on cultural history, the new cultural history and the history beyond the new cultural history in Swedish working class history

Culture has, during the last two decades or so, come to influence historical research in such a way that it is no understatement to speak of "the cultural turn", a change in paradigm fully comparable to "the social turn" in the 1960s. Cultural history, as a concept, has changed over time, from a classic cultural history in the first part of the twentieth century, where culture is seen as "the grea

Staden och resandet : Mötet mellan planering och vardagsliv

Popular Abstract in Swedish Avhandlingen behandlar vardagslivets resor i staden. Utgångspunkten är de negativa konsekvenser som resor, framför allt med bil, har för miljön. Bilismen är ett fenomen som dominerar stora delar av samhället och istället för att minska i omfattning tycks den själv driva fram ett ökat bilberoende genom att avstånden och kraven på snabba transporter ökar. I slutändan handUrban areas are geographically dispersed. There are built-in distances between housing, jobs and services. These distances call for mobility and fast means of conveyance. Society is dominated by and dependent on motoring. Cars have a negative impact on the environment and prognoses indicate an increase in the amount of travelling. The aim of this dissertation is to explain why travel behaviour wit

Tissue reactions evoked by porous and plane surfaces made out of silicon and titanium.

Square-shaped silicon or titanium implants with plane or porous surfaces surrounded by a rim of silicone were implanted in the rat abdominal wall for evaluation of the tissue response after one, six, or 12 weeks. Cell damage was identified as increased membrane permeability using fluorescence microscopy by injection of propidium iodide prior to the killing of the rats. Capsule thickness and immuno

Psychological factors and metabolic control in insulin-dependent diabetes mellitus

This doctoral thesis consists of six studies concerning persons with insulin dependent diabetes mellitus (IDDM). The first two deal with relationships between life events, social support and metabolic control (HbA1C) over a two year period. For the female subjects, results obtained for this period were inconsistent. For the male group, negative life events and poor social support were found to be

Performance of iterative CDMA receiver with channel estimation in multipath environments

Most works published on iterative CDMA receivers assume perfect channel knowledge or very simple channel models like the flat-fading channel. We want to extend the scope to multipath propagation scenarios and suggest an iterative scheme with channel estimation in the uplink of a chip-synchronous CDMA system. Channel estimates rely on pilot symbols and a posteriori probabilities on code bits of a S

The wood-decaying fungus Hygrophoropsis aurantiaca increases P availability in acid forest humus soil, while N addition hampers this effect

We evaluated the influence of the brown rot fungus Hygrophoropsis aurantiaca on P solubility in the humus layer of a podzolic forest soil. This fungus is known to exude large amounts of oxalic acid that may stimulate weathering of minerals and increase dissolution of humus, which in turn may increase P availability in the soil surrounding the fungus. Humus was inoculated using small wooden pieces

Body size and risk of colon and rectal cancer in the European prospective investigation into cancer and nutrition (EPIC)

Background: Body weight and body mass index (BMI) are positively related to risk of colon cancer in men, whereas weak or no associations exist in women. This discrepancy may be related to differences in fat distribution between sexes or to the use of hormone replacement therapy (HRT) in women. Methods: We used multivariable adjusted Cox proportional hazards models to examine the association betwee

A microarray approach for identifying mutated genes

This study was performed to evaluate if microarray technology can identify genes using their transcriptionally defective mutant alleles. Three barley (Hordeum vulgare L.) mutant strains, xantha-h57, xantha-f27 and xantha-g28, with mutations in the genes encoding the three subunits of the chlorophyll biosynthetic enzyme magnesium chelatase, were used in a reconstruction experiment. The mutation xan

Are important patient-rated outcomes in community mental health care explained by only one factor?

Introduction: The study tested whether four commonly used patient-rated outcomes are explained by only one factor, reflecting a general appraisal tendency of patients. Method: Quality of life, needs and symptoms were rated by 92 patients in community mental health care at baseline and after 18 months and 6 years follow-up periods. At follow ups treatment satisfaction was also assessed. Scores and

Evaluation of endometrial receptivity during in-vitro fertilization using three-dimensional power Doppler ultrasound

Objective To compare sonographic endometrial characteristics in in-vitro fertilization (IVF) cycles between women who conceive and those who do not. Methods Thirty-five women undergoing IVF treatment participated in the study. Using three-dimensional (3D) power Doppler ultrasound, we assessed endometrial patterns, volume and vascularization, after follicle stimulating hormone (FSH) stimulation but