Sökning: "Biologi"

Visar resultat 11 - 15 av 6266 avhandlingar innehållade ordet Biologi.

  1. 11. Biodiversity and Species Extinctions in Model Food Webs

    Författare :Charlotte Borrvall; Bo Ebenman; Owen Petchey; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; biodiversity; food webs; redundancy; relaxation time; stability; stochasticity; species deletion; species extinction; Biology; Biologi;

    Sammanfattning : Many of the earth’s ecosystems are experiencing large species losses due to human impacts such as habitat destruction and fragmentation, climate change, species invasions, pollution, and overfishing. Due to the complex interactions between species in food webs the extinction of one species could lead to a cascade of further extinctions and hence cause dramatic changes in species composition and ecosystem processes. LÄS MER

  2. 12. Comparative Seed Morphology and Phylogenetics : Case Studies in Basal Angiosperms (ANITA) and Asterids (Lysimachia, Ericales)

    Författare :Il-Chan Oh; Mats Thulin; Arne A. Anderberg; Bertil Ståhl; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biology; Biologi; systematisk botanik; Systematic Botany;

    Sammanfattning : The first half of the thesis deals with the seed morphology of members of the ANITA grade at the base of the angiosperm phylogeny (Amborella, Nymphaeales, Illiciales, Trimeniaceae, and Austrobaileyaceae), especially Illiciaceae and Schisandraceae. Seed characters support a major division between the New World and Old World species of Illicium. LÄS MER

  3. 13. Spatial Modelling of Coastal Fish – Methods and Applications

    Författare :Göran Sundblad; Ulf Bergström; Alfred Sandström; Peter Eklöv; Christian Möllmann; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; habitat; niche; species distribution modelling; juvenile; fish; larvae; spawning; Marine ecology; Marin ekologi; NATURAL SCIENCES; NATURVETENSKAP; Freshwater ecology; Limnisk ekologi; Biology; Biologi; Biology with specialization in Limnology; Biologi med inriktning mot limnologi; Biologi med inriktning mot zooekologi; Biology with specialization in Animal Ecology; Limnologi; Limnology;

    Sammanfattning : Environmental factors influence species and habitats on multiple scales creating a mosaic of distribution patterns. Studying factors shaping these patterns are central to our understanding of population dynamics and ultimately ecosystem functioning. LÄS MER

  4. 14. Cyanobacterial Hydrogen Metabolism : Regulation and Maturation of Hydrogenases

    Författare :Ellenor Devine; Peter Lindblad; Karin Stensjö; Laurent Cournac; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; cyanobacteria; hydrogenase; hydrogenase specific protease; maturation; regulation; transcriptional studies; hupW; hoxW; hyp; NtcA; CalA; Biology; Biologi; Molecular biology; Molekylärbiologi; Microbiology; Mikrobiologi; Chemistry with specialization in Microbial Chemistry; Kemi med inriktning mot mikrobiell kemi;

    Sammanfattning : In times with elevated CO2 levels and global warming there is a need of finding alternatives to carbon based energy carriers. One such environmental friendly solution could be H2 produced by living organisms. LÄS MER

  5. 15. Domestication Effects on the Stress Response in Chickens : Genetics, Physiology, and Behaviour

    Författare :Amir Fallahshahroudi; Per Jensen; Frank Albert; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Animal domestication; stress response; gene expression; QTL; eQTL;

    Sammanfattning : Animal domestication, the process where animals become adapted to living in proximity to humans, is associated with the alteration of multiple traits, including decreased fearfulness and stress response. With an estimated population of 50 billion, the domesticated chicken is the most populous avian species in the world. LÄS MER