Search for dissertations about: "Geographic pattern"

Showing result 1 - 5 of 56 swedish dissertations containing the words Geographic pattern.

2. 1. Morphometric differentiation in Papaver radicatum (Papaveraceae) : Geographic pattern and significance for refugial survival theory

   Author : Eva Selin; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; Capsule morphology; Geographic pattern; Leaf morphology; Morphometric variation; Papaver radicatum; Refugial survival; Seed shape; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Abstract : The morphometric pattern of variation among and within Scandinavian populations of the alpine species Papaver radicatum was studied. Results from analyses (including multivariate techniques) of capsule and leaf traits of wild-collected and cultivated plants as well as wild-collected seeds show correlated patterns of variation in capsule traits and partly corresponding patterns of variation between capsule and seed traits. READ MORE

4. 2. Geographic Distribution of Intra-specific Variation in Widespread Eurasian boreo-nemoral Woodland Herbs

   Author : Torbjörn Tyler; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; kemotaxonomi. Växters fysiologi inte kärlväxter .; Plant genetics; Växtgenetik; morfologi; chemotaxonomy. Physiology of nonvascular plants; Systematisk botanik; taxonomi; phytogeography; morphology; taxonomy; historical biogeography; Systematic botany; allozymes; population differentiation; postglacial migration; genetic variation; geographic variation;

   Abstract : Many woodland plant species have huge distribution areas covering large parts of the Eurasian continent including areas that were glaciated during the last glacial period. In the present thesis, the geographic distribution of variation within such species is investigated and discussed in relation to glacial survival and post-glacial migration, dispersal ability, breeding system and levels of gene-flow between populations and related species, and various methods to measure and analyse genetic variation. READ MORE

5. 3. Geographic differentiation and population history in Silene dioica and S. hifacensis: variation in chloroplast DNA and allozymes

   Author : Ursula Malm; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; morphology; taxonomy; Systematic botany; conservation biology; endemic; chloroplast DNA; allozyme; hybridization; gene flow; geographic variation; postglacial migration; genetic diversity; Silene; phytogeography; chemotaxonomy. Physiology of nonvascular plants; Systematisk botanik; taxonomi; morfologi; kemotaxonomi. Växters fysiologi inte kärlväxter .;

   Abstract : In this thesis I used allozymes and PCR-RFLP analysis of chloroplast DNA (cpDNA) to investigate geographic differentiation within the widespread Silene dioica (L.) Clairv. (Caryophyllaceae) and the narrowly-distributed S. hifacensis Rouy ex Willk. READ MORE

6. 4. Geographic and genetic diversity of hepatitis B

   Author : Erik Alestig; Göteborgs universitet; []
   Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; hepatitis B virus; genotype; phylogeny; molecular epidemiology; sequence analysis; mutation;

   Abstract : Hepatitis B Virus (HBV) infection is a global health problem and may lead to chronic hepatitis, liver cirrhosis and hepatocellular cancer. The ability of HBV to adapt to the host environment by genetic variation has lead to the evolution of 8 established (A-H) and 2 putative genotypes (I-J), each corresponding to a rather well-defined geographical distribution. READ MORE

7. 5. Geographic Routing in Intermittently-connected Mobile Ad Hoc Networks : Algorithms and Performance Models

   Author : Erik Kuiper; Simin Nadjm-Tehrani; Di Yuan; Mats Ekman; Timothy Brown; Linköpings universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : Communication is a key enabler for cooperation. Thus to support efficient communication humanity has continuously strived to improve the communication infrastructure. This infrastructure has evolved from heralds and ridden couriers to a digital telecommunication infrastructures based on electrical wires, optical fibers and radio links. READ MORE