Sökning: "Tree reconstruction"

Visar resultat 1 - 5 av 39 avhandlingar innehållade orden Tree reconstruction.

  1. 1. Computational problems in evolution : Multiple alignment, genome rearrangements, and tree reconstruction

    Författare :Isaac Elias; Jens Lagergren; Lior Pachter; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Distance Methods; Tree reconstruction; Sorting by Transpositions; multiple alignment; ancestral sequences; Computer science; Datavetenskap;

    Sammanfattning : Reconstructing the evolutionary history of a set of species is a fundamental problem in biology. This thesis concerns computational problems that arise in different settings and stages of phylogenetic tree reconstruction, but also in other contexts. LÄS MER

  2. 2. Late Holocene spatiotemporal hydroclimatic variability over Fennoscandia inferred from tree-rings

    Författare :Kristina Seftigen; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Tree-rings; Fennoscandia; hydroclimate; SPEI; SPI; ring-width; maximum latewood density; stable isotopes; field reconstruction; point-by-point regression;

    Sammanfattning : There is a broad scientific consensus that the global climate is changing, and that human activity is a significant factor contributing to the change. The response of the hydrological cycle to the warming is far reaching, including increases in the intensification and frequency of extreme hydroclimatological events. LÄS MER

  3. 3. Expanding the Chlamydiae tree : Insights into genome diversity and evolution

    Författare :Jennah E. Dharamshi; Thijs J. G. Ettema; Alexander Probst; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; PVC superphylum; Chlamydiae; chlamydia; intracellular; symbiosis; endosymbiont; pathogen; marine sediment; sponge microbiome; metagenomics; uncultured microbial diversity; phylogenomics; microbial evolution; eukaryote evolution; Biologi med inriktning mot molekylär evolution; Biology with specialization in Molecular Evolution;

    Sammanfattning : Chlamydiae is a phylum of obligate intracellular bacteria. They have a conserved lifecycle and infect eukaryotic hosts, ranging from animals to amoeba. Chlamydiae includes pathogens, and is well-studied from a medical perspective. LÄS MER

  4. 4. Interactions between climate, natural disturbances, and regeneration in boreal and hemi-boreal forests

    Författare :Igor Drobyshev; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; conservation strategies; Plant ecology; Växtekologi; taiga; seasonal climate; shoot increment; larch; reconstruction; human; canopy gap; fire history; boreal; natural disturbances; dendrochronology;

    Sammanfattning : Natural disturbance is an important driving force of community dynamics in many forest types around the globe. Understanding spatial and temporal properties of disturbance events in the present and in the past is important in formulating the nature conservation strategies as well as for the modeling of climate and human impacts on forest vegetation. LÄS MER

  5. 5. Intramolecular isotope analysis reveals plant ecophysiological signals covering multiple timescales

    Författare :Thomas Wieloch; Jürgen Schleucher; Mats Nilsson; Gerd Gleixner; Lisa Wingate; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NMR spectroscopy; tree ring; isotope ratio; isotope effect; intramolecular 13C 12C signal; carbon allocation; acclimation; plant performance; climate reconstruction; plant ecophysiology;

    Sammanfattning : Our societies' wellbeing relies on stable and healthy environments. However, our current lifestyles, growth-oriented economic policies and the population explosion are leading to potentially catastrophic degradation of ecosystems and progressive disruption of food chains. LÄS MER