Sökning: "selection"

Visar resultat 11 - 15 av 3292 avhandlingar innehållade ordet selection.

  1. 11. Male and female selective mechanisms, reproductive success and gene flow

    Författare :Samuel Kiboi; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Växtekologi; Plant ecology; Cucumis sativus.; genetic marker; gene flow; reproduction; embryo abortion; resistance; maternal selection; sexual selection; pollen competition; selection;

    Sammanfattning : In this thesis, I have studied male and female selective mechanisms that can affect plant reproductive success and gene flow. I have focussed on sexually selected traits, mainly pollen competition and maternal sorting mechanisms, for example through non-random ovule abortion. LÄS MER

  3. 12. Tracing selection and adaptation along an environmental gradient in Populus tremula

    Författare :David Hall; Pär Ingvarsson; Thomas Bataillon; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Local adaptation; Selection; genetic differentiation; QST; FST; Association study; frequency spectra; recurrent hitchhiking; selective sweep; Tree; Populus; natural selection; quantitative genetics; Terrestrial ecology; Terrestrisk ekologi; Population Biology; populationsbiologi; genetik; Genetics;

    Sammanfattning : The distribution of the expressed genotype is moved around in the population over time byevolution. Natural selection is one of the forces that act on the phenotype to change the patterns ofnucleotide variation underlying those distributions. LÄS MER

  4. 13. Pathogen-mediated selection in the immune system of rodents : Exploring selection targets, functional effects and trade-offs

    Författare :Mridula Nandakumar; Funktionell zoologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; pathogen-mediated selection; bank voles; Myodes glareolus; immune system; balancing selection; immune response; rodents; positive selection; transcriptomics;

    Sammanfattning : Pathogens cause disease and play an important role in shaping evolution of the host immune system. They create pressure on host immunity to evolve in numerous ways, most commonly by increasing divergence between species (positive selection) or increasing polymorphisms within a population (balancing selection). LÄS MER

  5. 14. Model Selection and Sparse Modeling

    Författare :Yngve Selén; Peter Stoica; Jean-Jacques Fuchs; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; model selection; model order selection; model averaging; nested models; sparse models; Bayesian inference; MMSE estimation; MAP estimation; ML estimation; AIC; BIC; GIC; RAKE receivers; pulse compression; radar; linear models; linear regression models; Signal processing; Signalbehandling;

    Sammanfattning : Parametric signal models are used in a multitude of signal processing applications. This thesis deals with signals for which there are many candidate models, and it is not a priori known which model is the most appropriate one. LÄS MER

  7. 15. Metals in Dynamic Chemistry: Selection & Catalysis

    Författare :Brian J.J. Timmer; Olof Ramström; Stéphane Bellemin-Laponnaz; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; constitutional dynamic chemistry; selection; multivalent interactions; carbohydrates; quartz crystal microbalance; catalyst screening; aqueous olefin metathesis; C-H activation; Kemi; Chemistry;

    Sammanfattning : In the adaptation to the oxidative environment on earth, metals played a crucial role for the evolution of life. The presence of metals also allowed access to advanced functions due to their unique coordination sphere and reactivity. LÄS MER