Sökning: "Negative selection"

Visar resultat 1 - 5 av 306 avhandlingar innehållade orden Negative selection.

  1. 1. Robust inference of gene regulatory networks : System properties, variable selection, subnetworks, and design of experiments

    Författare :Torbjörn E. M. Nordling; Elling W Jacobsen; Rolf Findeisen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; network inference; reverse engineering; variable selection; model selection; feature selection; subset selection; system identification; system theory; network theory; subnetworks; design of experiments; perturbation experiments; gene regulatory networks; biological networks;

    Sammanfattning : In this thesis, inference of biological networks from in vivo data generated by perturbation experiments is considered, i.e. deduction of causal interactions that exist among the observed variables. Knowledge of such regulatory influences is essential in biology. LÄS MER

  2. 2. 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

  3. 3. Evolutionary consequences of sex-specific selection

    Författare :Josefine Stångberg; Elisabeth Bolund; Elina Immonen; Jennifer Perry; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Caenorhabditis remanei; Callosobruchus maculatus; sex-specific selection; sexual selection; experimental evolution; intralocus sexual conflict; life history evolution; sexual dimorphism; trade-offs; Quantitative genetics;

    Sammanfattning : Sex-specific selection is widespread, evident by the evolution of sexual dimorphism in many traits in sexually reproducing taxa. The reason why the sexes may experience selection that differs in direction or magnitude is often linked to the reproductive strategies associated with the sex-specific reproductive physiology. LÄS MER

  4. 4. Population genomic analyses of regulatory variation and selection in Brassicaceae species

    Författare :Robert Horvath; Tanja Slotte; Peter Hambäck; Douglas G. Scofield; Matthew Webster; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Capsella grandiflora; Arabidopsis thaliana; Arabidopsis lyrata; natural selection; gene expression variation; DNA and gene body methylation; transposable elements; DNA accessibility; gene expression noise; epigenetic silencing; linked selection; ekologi och evolution; Ecology and Evolution;

    Sammanfattning : The impact of selection on regulatory variation and the contribution of regulatory changes to phenotypic variation has long been debated in evolutionary genetics. Because cis-regulatory elements such as promoters and enhancers can be difficult to identify, it has been more challenging to quantify the impact of selection on variation in cis-regulatory regions than in protein-coding regions. LÄS MER

  5. 5. Biological and Pharmacological Factor that Influence the Selection of Antibiotic Resistance

    Författare :Ingegerd Gustafsson; Otto Cars; Niels Frimodt-Möller; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Microbiology; Human microflora; antibiotic resistance; selection; mutation frequency; biological fitness; pharmacokinetics; pharmacodynamics; β-lactam antibiotics; suboptimal dosing regimen; Mikrobiologi; Microbiology; Mikrobiologi; Klinisk bakteriologi; Clinical Bacteriology;

    Sammanfattning : Antibiotic treatment causes an ecological disturbance on the human microflora. Four commensal bacteria: E. coli, enterococci, a-streptococci and coagulase-negative staphylococci, from patients with extensive, high antibiotic usage were investigated with regard to resistance pattern and mutation frequency. LÄS MER