Sökning: "marginal populations"

Visar resultat 26 - 30 av 38 avhandlingar innehållade orden marginal populations.

  1. 26. Factors regulating lymphocyte development and peripheral activation

    Författare :Anna Makowska; Malmö Institutionen för kliniska vetenskaper; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; transplantation; serology; Immunology; NKT cells; TFG beta; Treg; Immunologi; serologi;

    Sammanfattning : Peripheral tolerance is regulated by different types of regulatory T cells, including CD1-restricted T cells and CD4+CD25+ regulatory T (Treg) cells. This thesis has focused on the interactions between T cells and antigen presenting cells (APCs) and the immunregulatory function of TGF-b as two important factors regulating differentiation and activation of T cells in the periphery. LÄS MER

  3. 27. Macroalgae in the Baltic Sea : responses to low salinity and nutrient enrichment in Ceramium and Fucus

    Författare :Lena Bergström; Lars Ericson; Lena Kautsky; Erik Bonsdorff; Christine A Maggs; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; adaptation; asexual reproduction; Baltic Sea; Gulf of Bothnia; salinity; macroalgae; nutrients; sexual reproduction; stress; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : 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. LÄS MER

  4. 28. Holocene climate change and peatland dynamics in southern Sweden based on tree-ring analysis of subfossil wood from peat deposits

    Författare :Johannes Edvardsson; Kvartärgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; The Holocene.; Peatland development; Scots pine; Palaeoclimatology; Dendrochronology; Subfossil trees; Raised bog; Palaeohydrology;

    Sammanfattning : Dendrochronological analysis was applied to subfossil remains of Scots pine (Pinus sylvestris L.) buried in South Swedish peat deposits. LÄS MER

  5. 29. Age-class interactions in Atlantic salmon and brown trout: Effects on habitat use and performance

    Författare :Rasmus Kaspersson; Göteborgs universitet; []
    Nyckelord :competition; inter-cohort; density-dependence; growth; habitat; Salmo trutta; Salmo salar; salmon; trout;

    Sammanfattning : This thesis investigates the underlying mechanisms and the density-regulatory effects of age-class interactions, using juvenile Atlantic salmon (Salmo salar L.) and brown trout (Salmo trutta L.) as study species. LÄS MER

  7. 30. The effects of temperature on avian physiology, behavior and development

    Författare :Andreas Nord; Evolutionär ekologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; clutch size; Cyanistes caeruleus; ecological immunology; energy expenditure; fever; Ficedula hypoleuca; heterothermy; hypothermia; incubation; life history; metabolic rate; Parus major; RMR; Taeniopygia guttata; temperature; winter;

    Sammanfattning : Temperature is a property of profound matter in all aspects of animal life, affecting both individual energy budgets and the environments in which animals reside. Thus, a proper understanding of the effects of temperature variation is instrumental in understanding not only animal form and function, but also the structure and dynamics of wild populations. LÄS MER