Sökning: "natural selection"

Visar resultat 36 - 40 av 1236 avhandlingar innehållade orden natural selection.

  1. 36. eScience Approaches to Model Selection and Assessment : Applications in Bioinformatics

    Författare :Martin Eklund; Jarl Wikberg; Ron Wehrens; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; bioinformatics; high-throughout biology; eScience; model selection; model assessment; Bioinformatics; Bioinformatik;

    Sammanfattning : High-throughput experimental methods, such as DNA and protein microarrays, have become ubiquitous and indispensable tools in biology and biomedicine, and the number of high-throughput technologies is constantly increasing. They provide the power to measure thousands of properties of a biological system in a single experiment and have the potential to revolutionize our understanding of biology and medicine. LÄS MER

  3. 37. Runge–Kutta Time Step Selection for Flow Problems

    Författare :Karl Hörnell; Per Lötstedt; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Runge-Kutta; stepsize selection; optimization; flow problems; numerical analysis; Numerical Analysis; Numerisk analys;

    Sammanfattning : Optimality is studied for Runge-Kutta iteration for solving steady-state and time dependent flow problems. For the former type an algorithm for determining locally optimal time steps is developed, based on the fact that the squared norm of the residual produced by an m-stage scheme is a 2m-degree polynomial, the coefficients of which can be computed from scalar products of Krylov subspace vectors. LÄS MER

  4. 38. Postmating Sexual Selection and its Role in Population Divergence in Beetles

    Författare :Claudia Fricke; Göran Arnqvist; David Hosken; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biology; Callosobruchus maculatus; postmating sexual selection; speciation; laboratory selection experiment; divergence; Biologi; Biology; Biologi;

    Sammanfattning : Speciation is the process describing the formation of new species and is at the heart of evolutionary biology. According to the biological species concept only reproductively isolated forms are regarded good species. This thesis aims at identifying evolutionary processes that cause population divergence and, ultimately, speciation. LÄS MER

  5. 39. Avian MHC: variation and selection in the wild

    Författare :Helena Westerdahl; MEMEG; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; polymorphism; balancing selection; cDNA; avian malaria; great reed warbler; Djurekologi; bird; Animal ecology; immune defence; MHC class II; Major Histocompatibility Complex; MHC class I;

    Sammanfattning : In vertebrates the Major Histocompatibility Complex (MHC) plays a central role in the specific immune defence against various pathogens. Compared with other coding genes the MHC genes exhibit an extremely high level of polymorphism that is maintained by balancing selection. LÄS MER

  7. 40. Detecting Signatures of Selection within the Dog Genome

    Författare :Abhirami Ratnakumar; Matthew Webster; Kerstin Lindblad-Toh; Greg Barsh; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; dog; evolution; domestication; PRDM9; recombination; positive selection; selective sweep;

    Sammanfattning : Deciphering the genetic basis of phenotypic diversity is one of the central aims of biological research. Domestic animals provide a unique opportunity for making substantial progress towards this goal. LÄS MER