Artificial ground freezing as a method to temporarily stabilize and create hydraulic sealing in urban as well as in rural areas has been used in a number of Swedish construction projects, particularly during the last decade. One problem with the freezing of soil and rock is that fine-grained clayey types of soils have showed a tendency to under certain circumstances, during the thawing process, create a pore water overpressure and to consolidate, despite a change in the external loading conditions. In certain cases, this condition can be a desired effect as the soil mass after a freeze- and thaw cycle acquires overconsolidated properties. The main objectives of this study are, to describe and review the knowledge and current state of practice of artificial ground freezing, to increase the understanding about the conceptual behaviour for prognosis of the vertical deformation concerning artificial ground freezing and to compare and discuss results from laboratory and field studies concerning vertical deformation during thawing process for Bothnia soil. The field studies and the laboratory tests in this research study have been performed with soil from the freezing of the Bothnia Line in the vicinity of Stranneberget. The Bothnia Line is the railway link between Nyland, north of Kramfors, and Umeå. This thesis relates to a part of the Bothnia Line. It deals with the behaviour of soil during thawing by means of temporary stabilization and hydraulic sealing of fine-grained soil through artificial freezing using brine as the cooling agent. However, the reason behind the problem consists of the final deformations due to the thawing process. The general conclusions of this study are; the Bothnia soil water content decreased in mean approximately 14 % after a freeze-thaw cycle, which approximately corresponds to; wth = 0.8w – 1.5 the decrease of the water content has no correlation to the depth below ground surface, in contrast, there is a strong correlation between the undisturbed soil water content and the magnitude of the decrease in water content the soil liquid limit decreases after a freeze-thaw cycle, simultaneously as the relative share of clay and fine silt grains decreases while the relative share of more coarse grains increases the coarser and denser soil created after a freeze-thaw cycle obtains an increased preconsolidation pressure and an increased undrained shear strength. / QC 20100721

The brackish Baltic Sea is a marginal environment for both marine and freshwater species. The rate of ecological differentiation is presumably high due to strong selection pressure from a gradient of decreasing salinity that has been present in its current state for only about 3 000 years. Even more recently, increased nutrient loading due to human activities has affected the growth rate of species, with potential effects on their competitive interactions and responses to other regulating factors. I have investigated the potential effects of low salinity and nutrient enrichment on the distributional ranges of two marine macroalgae with a wide distribution in the Baltic Sea, the red alga Ceramium tenuicorne (Kütz.) Wærn and the brown alga Fucus vesiculosus L. A field study in the northern Baltic Sea indicated a strong relationship between the community structure of macroalgae and abiotic factors even on a small, local scale. The abiotic factors are potentially modulated by eutrophication, which may have a strong effect on the depth distribution and abundance of macroalgae. On a regional scale, laboratory experiments suggested that nutrient enrichment is unlikely to affect the distribution of Ceramium and Fucus along the salinity gradient. Growth in Ceramium from the Baltic Proper was enhanced by nitrate and phosphate, but the response did not override growth constraints due to low salinity. Ceramium from the Gulf of Bothnia had an inherently lower growth rate that was not positively affected by nitrate and phosphate increase. In Fucus vesiculosus, reproductive performance was impaired by nitrate and phosphate levels corresponding to ambient levels in eutrophicated areas of the Baltic Sea, when measured by their effect on zygote attachment, germination, and rhizoid development. The wide distribution of Ceramium in the inner Baltic Sea is probably related to local adaptation, rather than a generalized tolerance of different salinity levels. Ecotypic differences were observed when comparing strains from the Baltic Proper (salinity 7 psu) and the Gulf of Bothnia (4 psu). A high rate of vegetative reproduction was evident, although sexual reproduction was occasionally observed in salinity 4. In Fucus vesiculosus, genetic and morphological analyses of sympatric and allopatric populations of the common, vesicular, morphotype and a dwarf morphotype, characteristic for the Gulf of Bothnia, showed that the dwarf morphotype represents a separate evolutionary lineage. Also, vegetative reproduction was observed in Fucus for the first time, as supported by genetic and experimental data. The results show that the biota of the inner Baltic Sea may have unique adaptive and genetic properties, and that it is highly relevant to consider subspecies diversity in Baltic Sea management.

Middle managers have a complex task where it is important to achieve results while at the same time being there for their employees. To succeed in this, a good structure in the work and the right type of support from both management and employees are required. This study aims to investigate how middle managers experience the support that the respective companies provide and how the experiences can be understood based on the JDCS model. Ten semi-structured interviews were conducted with middle managers at two different businesses. The interviews were transcribed orthographically and then analyzed thematically. The results showed that the support function is central when it comes to handling the high demands that are made, as well as how management forums can contribute to increasing community and collegial support among middle managers. The conclusion that could be drawn was that in order to avoid burdensome work and increase satisfaction, a comprehensive support function is required.

Diss. (sammanfattning) Umeå : Umeå universitet, 2009. / Härtill 4 uppsatser. Även tryckt utgåva.

With a foundation in social sustainability, and with the theoretical framework of transport justice and transport poverty, the aim of this thesis is to create a profile picture of the future potential travelers on the North Bothnia Line in Sävar, Robertsfors and Bureå. Both a quantitative and a qualitative analysis are performed. The quantitative analysis describes the population structures concerning age, gender, educational level, employment, household type, income and cars per 1000 inhabitants. The qualitative analysis consists of an interview study, conducted in Robertsfors, with 47 informants. The interview answers are analyzed through content analysis, and presented in personas for each age group. The three areas differ in population structure, which could have different implications on the future travel. In the planning for a socially sustainable travel with the North Bothnia Line, focus needs to be directed to the young travelers, in particular the high school youths. Families with children are facing constraints when trying to manage sustainable travel, therefore, how to create a socially sustainable travel for this group is important to consider in the planning. Young adults, as well as individuals that are unemployed are vulnerable groups, important to consider. The senior travelers have another travel behavior, compared to the population of working age, but still have their needs connected to travel. The informants are positive about the North Bothnia Line, positive about train as travel mode, and intend to use the future train. They expect that the train will lead to easier and faster transportation and work commuting, increased access to schools and jobs, population growth, open up for more opportunities, and that people do not have to own a car. The greatest needs are; a good timetable, with many departures, matching the work schedule. The train has to be on time, and the ticket price not too high. Both the train and the station have to be easily accessible, supplied with good car parking facilities with engine heaters, and the train has to go fast. Both the train and the station have to be clean and controlled, and there has to be clear, and digital information. / Norrbotniabanans noder 2