Search for dissertations about: "Different sizes"

Showing result 1 - 5 of 738 swedish dissertations containing the words Different sizes.

  2. 1. Inbreeding, Effective Population Sizes and Genetic Differentiation : A Mathematical Analysis of Structured Populations

    Author : Fredrik Olsson; Ola Hössjer; Steinar Engen; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; matematisk statistik; Mathematical Statistics;

    Abstract : This thesis consists of four papers on various aspects of inbreeding, effective population sizes and genetic differentiation in structured populations, that is, populations that consist of a number of subpopulations. Three of the papers concern age structured populations, where in the first paper we concentrate on calculating the variance effective population size (NeV) and how NeV depends on the time between measurements and the weighting scheme of age classes. READ MORE

  4. 2. Food webs and the distribution of body sizes

    Author : Tomas Jonsson; Linköpings universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : Many ecologically relevant life-history traits of organisms, (such as generation time and ingestion rate) are significantly correlated to body size. Since these individual and species characteristics can affect the interactions between the species in a community, it is possible that the distribution of body sizes (in communities) can affect different properties of foodwebs as well. READ MORE

  5. 3. Different paths to explore confined crystallisation of PCL

    Author : Nima Sanandaji; Ulf W. Gedde; Mikael S Hedenqvist; Javier Martinez de Salazar; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; crystallisation; poly-ε-caprolactone; end groups; morphology; nanoconfinement; melting; monodisperse; RESS; injet printing;

    Abstract : In this work, different paths to confined crystallisation of poly(ε-caprolactone) (PCL) havebeen explored. Innate confinement effects due to the presence of bulky end groups wereshown to affect crystalline characteristics for strictly monodisperse ε-caprolactone oligomers. READ MORE

  6. 4. The different roles of crayfish in benthic food webs

    Author : Patrik Stenroth; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Marinbiologi; limnologi; aquatic ecology; marine biology; food chain length; stable isotopes; environmental gradients; diet; crayfish; akvatisk ekologi; limnology; Hydrobiology;

    Abstract : I show that crayfish consume detritus, algae, macrophytes, and an array of invertebrates. Crayfish were found to reduce invertebrate densities. However, prey mobility seemed to be a key factor regulating the strength of interactions between crayfish and prey. READ MORE

  7. 5. Simulations of Cosmic Reionization : Shapes & Sizes of H II regions around Galaxies and Quasars

    Author : Martina M. Friedrich; Garrelt Mellema; Jonathan Pritchard; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Astronomy; astronomi;

    Abstract : After the era of recombination, roughly 360 000 years after the big bang (redshift 1100), the universe was neutral, continued to expand and eventually the first gravitationally collapsed structures capable of forming stars, formed. Observations show that approximately 1 billion years later (redshift 6), the Universe had become highly ionized. READ MORE