The fallout from the Chernobyl nuclear accident resulted in large deposits of caesium, iodineand strontium as well as noble gases in various parts of Sweden. 137Cs has a radioactive halflifeof about 30 years and is therefore one of few radio-fission products remaining inmeasurable quantities in the Swedish soil. Radiocaesium behaves similarly to potassium insoil-plant systems and is easily absorbed by plants. It is important to understand how 137Csbehaves in different ecosystems in order to minimize the risk toward humans.The aim of this study was to determine how potassium fertilization influences radiocaesiumcontent in different forest plants and fungi. Potassium fertilizer was spread once in 1992 withapproximately 200 kg KCl per ha.

Abstract The purpose of this study is to examine how teachers in primary school reason about and problematize the phenomenon of concentration difficulties. I want to know what the teachers think characterizes concentration difficulties, the situations in which difficulties creates the most problems, and whether the teachers think that these difficulties solely depend on external factors. To examine this, I chose to do interviews with three teachers in years four to six. I have completed parts of my work with my colleague Elin Preisz. We have used the same purpose and issues in our studies, although Elin has interviewed teachers in preschool. With this we want to be able to compare the reasoning between teachers at different stages in school. The results of my study shows that the interviewees think that it is hard to describe what characterizes the problems in concentration difficulties because the problems is very individual.

In organic animal production, synthetic amino acids are not allowed. Therefore, a higher level of crude protein is needed in the diet to pigs, which lead to more nitrogen (N) excreted in the faeces and urine. N can be emitted to the air in the form of e.g. ammonia (NH3), which contributes to eutrophication and acidification and as nitrous oxide (N2O), which is a very potent greenhouse gas. The emission of N can be reduced by e.g.

In Sweden there is a long ongoing discussion about computer and cellphone usage during lectures in school. The discussion has mainly covered elementary school up to college students, but this topic is at least as relevant for university students. Today cellphones are so advanced; you can do everything with one that you previously only could do with a computer, the difference is that everyone is carrying one with them all the time. This study shows how concentration during lectures is affected by the cellphone accessibility and usage. With this study we want to find out how university students perceive cellphone usage affects their own concentration during lectures.

Abstract The purpose of this study is to examine how teachers in primary school reason about and problematize the phenomenon of concentration difficulties. I want to know what the teachers think characterizes concentration difficulties, the situations in which difficulties creates the most problems, and whether the teachers think that these difficulties solely depend on external factors. To examine this, I chose to do interviews with three teachers in years four to six. I have completed parts of my work with my colleague Elin Preisz. We have used the same purpose and issues in our studies, although Elin has interviewed teachers in preschool. With this we want to be able to compare the reasoning between teachers at different stages in school. The results of my study shows that the interviewees think that it is hard to describe what characterizes the problems in concentration difficulties because the problems is very individual.

There is a strong debate in the media about the CEO compensation in the listed companies and whether they deserve their high rewards. Many previous studies have shown differences in the reward system depending on the ownership structure, mostly testing for only ownership concentration or ownership category. This study aims to investigate how the influence of the owners affects the CEO reward system, testing for both the level and the structure of the reward. The sample used in the investigation is Swedish listed corporations and consists of 251 observations. A survey was also conducted but due to low response rate and because the answers are not representative for the whole sample the survey will only be used as an illustration.

The study is made on behalf of SCA Skog Jämtlands förvaltning which is one of five administration units that SCA Skog consists of. The purpose of the study is to investigate which reduced expenses there are according to spatial concentration of cutting areas. By increasing the spatial concentration of cutting areas it will reduce the need of movements by trailer, also reduce the number of roads that you use during the activities. To be able to perform the study, access to a annual cuttings in nine years have been made available. From this volume new annual cuttings has been created but more concentrated. The two different results have been compared and the results show that concentration of cutting areas generates reduced need for trailer transports and less km road that has to be maintained. But then, if it´s practical viable can be discussed.

Toxic metals contaminate soil worldwide and thus serve as sever environmental threat. Therefore the purposes of this study were to investigate in which soil fractions that different heavy metals (Fe, As, Cu, Zn and Pb) could be found in contaminated soils and if it is possible to use sieving as a method for decontamination. Soil samples were collected from three different locations, the Nasa silver mine, the Blaiken-mine and Svalget environmental station. The samples were oven dried and later on sieved into six different fractions 8mm, 4 mm, 0.5 mm, 0.250mm, 0.063 mm and <0.063 mm. The fractions 4 mm, 0.5 mm and <0.063 mm from each location were analyzed in an x-ray fluorescence detector.

Nitrogen deposition leads to environmental damage in areas where the nitrogen deposition is high. Southwest Sweden receives an annual nitrogen deposition of up to 20 kg N/ha. Nitrogen that is not assimilated by the vegetation is accumulated in the soil, which may lead to nitrogen saturation and an elevated risk of nitrogen leaching. Nitrogen leaching from forest areas in southern Sweden has proven to be higher than from agricultural areas, which have been thought to be the main contributors to elevated nitrogen levels in rivers and lakes. The amount of nitrogen that leaches depends on the fraction of the total nitrogen in the soil that consists of nitrate, since nitrate is easily transported through the soil.

Active ownership is widely regarded as positive for the development and performance of businesses. In this paper, we investigate the impact of ownership concentration and owner identity on return on equity (ROE) in Swedish companies between 1986 and 2008, and show that active ownership might suffer from opposing effects. We find evidence, albeit weak, that ownership concentration has a positive effect on profitability, but that it levels off at high levels of ownership shares. Furthermore, we propose that family ownership has a negative effect on profitability. Our results are dependent of choice of statistical method, but show nonetheless a need to reevaluate what seems to be a universally positive view of active ownership..

Storm water is defined as runoff from precipitation such as rain or snow. It is collected in sewage disposal systems and since it mainly originates from urban areas it can contain high levels of heavy metals, nutrients and oil etc. Polluted storm water is currently treated by different methods such as wet ponds, constructed wetlands and filter strips. This study investigates these methods, which in earlier studies have shown to give varying results regarding their treatment efficiency.This thesis has been written on commission of SWECO VIAK and was aimed at studying those parameters that may affect the treatment efficiency of nutrients and heavy metals in storm water treatment facilities (STF:s). Through literature studies the dominating treatment processes in ponds and wetlands were examined.

During the past few years a vast amount of research has been done to increase the understanding of the complex ecosystem of the Baltic Sea. Modelling and simulations are important tools to increase knowledge of the system. A suitable model must be simple to use and the parameters and variables needed in the model must be easy to access.In this paper a dynamical mass-balance model, CoastMab, which is validated for smaller coastal areas, has been used to predict concentrations and transports of phosphorus in three large coastal areas - the Gulf of Finland, the Gulf of Gdansk and the Gulf of Riga. CoastMab uses ordinary differential equations to regulate inflow, outflow and internal flows. To reflect seasonal variations in temperature and different types of flows the model has a temporal resolution of a month.

This is an essay concerning the density of the city. An increasing amount of today?s cities have a shortage of space available for the erection of new buildings and settlements, especially in areas close to the city-centre. New buildings and settlements are therefore often found in the outskirts of the city, resulting in long distances between work and living for many people. These long distances are a waste of limited resources and are inconsistent with the vision of the sustainable city.The challenge for the future is to insert new buildings and settlements in the existing city-structure and in this way reduce the distances between different city-functions.The density of the city can be increased in two different ways; by inserting new buildings between existing ones or by extension existing buildings, for example by an additional floor.

A system for sampling of alcohol and aldehyde from diluted exhaust gases from vehicles powered by ethanol has been developed and tested. The major part of the work has been research of earlier work in the field and the construction of the sampling system.The part of the system constructed for the measurement of alcohol has been shown to work, however, more test should be performed. The part of the system constructed for the measurement of aldehyde was tested parallel to a commercially available system, based on the same principle of measurement, and has been shown to work well.Determination of the concentration of gaseous ethanol using a FID has shown the since earlier known fact that a FID is not able to measure a correct concentration of ethanol. Furthermore it has been shown that high concentrations of gaseous ethanol can not be kept in a bag more than a few minutes without a substantial decrease of the measured concentration..

The purpose of this investigation was to investigate how being outdoors and participating in physical activities affect the concentration in a collection situation among children.The methods I chose were observation of two groups of children two times each and interviews with four educators.The results showed that the concentration in the collected situation depends on past activity, where it has taken place and that the environment has an impact. If the previous activity been more active and physical the subsequent collected situation is calmer and the children more concentrate. The facts that the children have been outside in an inspiring environment that encourage playing and movement also have a position impact on the child´s ability to concentrate. The collected situation is an important moment in the preschool day when the kids need to congregate and get a chance for social interaction and a sense of togetherness with all the children and teachers. The conclusion is that there is a relationship between movement, physical activity and an increased concentration.