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Visar resultat 1 - 5 av 6 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Biodiversity in fragmented boreal forests : assessing the past, the present and the future

    Författare :Håkan Berglund; Bengt Gunnar Jonsson; Jari Kouki; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; bryophytes; CWD; edge effects; fragmentation; fungi; habitat destruction; historical records; indicator; lichens; regression; species-area relationship; value pyramids; woody debris; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : The aims of this thesis are to (1) analyze the predictability (indicators) of plant and fungal species diversity in old-growth forests, and (2) assess the history and biodiversity of woodland key habitats (WKHs) and their potential to maintain species diversity in fragmented boreal forest landscapes. Predictability was explored in Granlandet nature reserve, an unexploited landscape composed of discrete old-growth Picea forest patches of varying size isolated by wetland, reflecting conditions of insular biota at stochastic equilibrium. LÄS MER

  3. 2. Function and dynamics of woody debris in boreal forest streams

    Författare :Niklas Dahlström; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Boreal forest; CPOM; CWD; forest management; geomorphology; LWD; riparian forest; retention; residence time; streams; Sweden; woody debris; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

    Sammanfattning : The work in this thesis deals with (1) the effects of woody debris on stream channel morphology and retention of organic material, and (2) the dynamics of woody debris and its relation to riparian forest history and composition. The studied stream reaches are situated in mature, productive forests in the boreal zone of Sweden. LÄS MER

  4. 3. Cost-effectiveness of measures to improve biodiversity in Swedish forests

    Författare :Hans Ekvall; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : The main objective of this thesis is to analyse the cost-effectiveness of measures, which improve biodiversity among life forms dependent on coarse woody debris (CWD). The amount of CWD in forest land has decreased due to modern forest management. LÄS MER

  5. 4. Characterization of the prion protein in relation to normal cellular function and in disease

    Författare :Lotta Wik; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Transmissible spongiform encephalopathies (TSEs), also known as prion diseases, are a group of rare and fatal neurodegenerative disorders that can affect both human and animals. Evidence indicates that the key event in prion disease pathogenesis is the conformational conversion of the normal cellular prion protein (PrPC) into an aggregated isoform called the scrapie prion protein (PrPSc). LÄS MER

  7. 5. Middle Ear Cholesteatoma : Surgical Treatment, Follow-up and Hearing Restoration

    Författare :Lennart Edfeldt; Helge Rask-Andersen; Juha Silvola; Uppsala universitet; []
    Nyckelord :Oto-Rhino-Laryngology; Oto-rhino-laryngologi;

    Sammanfattning : Although middle-ear cholesteatoma is a major topic in otological research, its etiology and pathogenesis remain unclear. Pediatric cholesteatoma is considered more aggressive than adult cholesteatoma, as it has a higher rate of growth, is more often infected and exhibits wider extension. LÄS MER