Sökning: "KA"

Visar resultat 21 - 25 av 118 avhandlingar innehållade ordet KA.

  1. 21. Late Quaternary climate and environmental change in the summer rainfall region of South Africa : A study using trees and wetland peat cores as natural archives

    Författare :Elin Norström; Karin Holmgren; Michael Meadows; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; paleoclimate; Late Quaternary; pollen; stable isotopes; diatoms; phytoliths; dendroclimatology; South Africa; Physical geography; Naturgeografi; Physical Geography; naturgeografi;

    Sammanfattning : This thesis contributes with information on past climate and environmental changes in South Africa’s summer rainfall region. The study is based on multi-proxy analyses on wetland peat cores and analyses of stable isotope composition (δ13C, δ18O) and wood anatomy in cross sections from subtropical trees (Breonadia salicina). LÄS MER

  3. 22. A-type Potassium Channels in Dendritic Integration : Role in Epileptogenesis

    Författare :Jenny Tigerholm; Erik Fransén; Fredrik Elinder; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; epileptogenesis; fast ripples; synchronicity; dendritic potentials; transient A–type potassium current; KV 4.2; Computer and systems science; Data- och systemvetenskap;

    Sammanfattning : During cognitive tasks, synchronicity of neural activity varies and is correlated with performance. However, there may be an upper limit to normal synchronised activity – specifically, epileptogenic activity is characterized byexcess spiking at high synchronicity. LÄS MER

  4. 23. Speleothems from Warm Climates : Holocene Records from the Caribbean and Mediterranean Regions

    Författare :Meighan Boyd; Karin Holmgren; Ian J. Fairchild; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Stable isotopes; U-Th dating; trace elements; stalagmite; speleothem; Mid-Holocene; Caribbean; ITCZ; rapid climate change; climate; Eastern Mediterranean; Peloponnese; Santorini; Neolithic; Alepotrypa Cave; Physical Geography; naturgeografi;

    Sammanfattning : This thesis contributes to increased knowledge on Holocene climate and environmental variability from two complex and sparsely studied areas. Using a speleothem from Gasparee Cave, Trinidad, as a paleoclimate archive, the local expression of the 8. LÄS MER

  5. 24. Paleoglaciology of Shaluli Shan, southeastern Tibetan Plateau

    Författare :Ping Fu; Arjen Stroeven; Lewis Owen; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Paleoglaciology; Tibetan Plateau; geomorphological mapping; cosmogenic nuclide; Last Glacial Maximum; glacial erosion; basal thermal regime; paleoglaciologi; Tibetanska platån; geomorfologisk kartering; kosmogena isotoper; senaste glaciala maximat; glacial erosion; subglacial temperatur; Physical Geography; naturgeografi;

    Sammanfattning : Reconstructing the paleoglaciation of the Tibetan Plateau is critical to understanding linkages between regional climate changes and global climate changes. This work focuses on the paleoglaciology of the Shaluli Shan Mountain area in the southeastern Tibetan Plateau. LÄS MER

  7. 25. Role of cytokines in experimental neurodegenerative and neuroinflammatory disorders

    Författare :Xing-Mei Zhang; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :;

    Sammanfattning : Altered expression of cytokines in response to body injury has diverse actions that can exacerbate, mediate, reduce or inhibit neuronal and myelin damage as well as influence the disease development in a variety of nervous system disorders, such as Alzheimer s disease (AD), multiple sclerosis and Guillain-Barré Syndrome (GBS). In these studies, we attempted to explore the possible roles of tumor necrosis factor (TNF)-α and interleukin (IL)-18 in experimental neurodegenerative and neuroinflammatory disorders. LÄS MER