Sökning: "Range margins"

Visar resultat 1 - 5 av 30 avhandlingar innehållade orden Range margins.

  1. 1. Microclimate at range margins : Consequences for boreal forest understory species

    Författare :Caroline Greiser; Kristoffer Hylander; Johan Ehrlén; Eric Meineri; Miska Luoto; Alistair Jump; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; NATURAL SCIENCES; microclimate; species distribution; range dynamics; boreal forest; canopy cover; topography; soil moisture; air humidity; bryophytes; lichens; vascular plants; biotic interactions; forest management; biodiversity conservation; ekologi och evolution; Ecology and Evolution;

    Sammanfattning : A warmer climate will shift species distributional range margins poleward, but near-ground microclimates may modify these shifts. Cold-adapted northern species at their rear edge may survive locally in microrefugia with a colder microclimate, and warm-adapted southern species at their leading edge may colonize stepping stone habitats with a warmer microclimate. LÄS MER

  2. 2. Proactive Range Management : A Timber Supplier’s Efforts to Influence the Product Assortment of Builders’ Merchants

    Författare :Daniel Ellström; Jakob Rehme; Tomas Nord; Daniel Nordigården; Daniel Chicksand; Linköpings universitet; []

    Sammanfattning : Different builders’ merchants demand a variety of products, and no effort has yet been made to coordinate these demands. Therefore, suppliers of timber to builders’ merchants are facing a problem in terms of requirements for a product range that is too extensive. LÄS MER

  3. 3. Modelling the Evolution of Species’ Ranges

    Författare :Martin Eriksson; Göteborgs universitet; Göteborgs universitet; Gothenburg University; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Range expansions; Range margins; Population genetics; Evolutionary biology; Local adaptation; Environmental selection; Phenotypic plasticity; Computer simulations;

    Sammanfattning : The fact that species have limited ranges is often due to a limited ability to adapt to the environmental conditions that occur outside their geographic ranges. However, due to ongoing climate change, the environmental conditions within species’ geographic ranges may change in the near-future. LÄS MER

  4. 4. Ensuring the intended volume is given the intended absorbed dose in radiotherapy: Managing geometric variations and treatment hazards

    Författare :Ola Holmberg; Malmö Medicinsk strålningsfysik; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; medical instrumentation; tomography; radiology; Clinical physics; safety; risk; hazard; organ motion; set-up; margins; volume definition; radiotherapy; accuracy; Klinisk fysiologi; radiologi; tomografi; medicinsk instrumentering; Radiopharmaceutical technology; Radiofarmaceutisk teknik;

    Sammanfattning : Methods for ensuring that the intended volume receives the intended absorbed dose in radiotherapy have been investigated. In order to optimise radiation treatment of cancer, geometric variations in the treatment chain need to be controlled. Furthermore, hazards potentially leading to unintended irradiation need to be controlled. LÄS MER

  5. 5. Robust optimization of radiation therapy accounting for geometric uncertainty

    Författare :Albin Fredriksson; Anders Forsgren; Timothy C. Y. Chan; KTH; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; Optimization; intensity-modulated proton therapy; uncertainty; robust planning; setup error; range error; intensity-modulated radiation therapy; multicriteria optimization;

    Sammanfattning : Geometric errors may compromise the quality of radiation therapy treatments. Optimization methods that account for errors can reduce their effects.The first paper of this thesis introduces minimax optimization to account for systematic range and setup errors in intensity-modulated proton therapy. LÄS MER