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Hybridisation in bluebells (Hyacinthoides spec.) using next-generation sequencing to reconstruct a natural hybrid zone in SpainMarquardt, Jeannine January 2017 (has links)
Hybridisation is a common evolutionary process that can arise in primary or secondary contact. Gene ow and/or reproductive isolation between hybridising taxa can be explored in hybrid zones. Therefore, a (homoploid) hybrid zone in north-west Spain between Hyacinthoides non-scripta and H. hispanica was studied. The centre occurs west to east across the Galicio-Duero Mountains with H. non-scripta distributed north, and H. hispanica south of the centre. The hybrids' genome sizes and phenotypes represented a range of intermediate states between their parents. Crossing and seed germination experiments revealed a low inter-speci c barrier, and the hybrids showed similarly good tness. Genome wide markers for large genome species were designed from transcriptomes. Diagnostic SNPs between H. non-scripta and H. hispanica were targeted and re-sequenced with multiplexing PCR. Coalescence analyses suggested a Pleistocene origin of parapatric speciation between H. non-scripta and H. hispanica. These results are supported by shared inter-speci c polymorphisms, the lack of recent hybrid generations and of parental individuals in sympatry. Di erential introgression patterns between the organellar and nuclear genomes revealed that formerly H. hispanica ranged further north but was swamped by H. non-scripta alleles. Asymmetric hybridisation was reasoned by absence of backcrosses between northern hybrids to H. non-scripta, but presence between southern hybrids and H. hispanica. Combining these results, a southwards movement of the hybrid zone centre caused by climate change (and adaptive introgression), or inter-speci c di erences in owering time was suggested. Cline patterns revealed cyto-nuclear incompatibilities, which could evolve through divergent adaptation of the organelle to climate and a delayed selection on nuclear inter-acting loci. Both species are in secondary contact in the UK due to recent introduction(s) of H. hispanica and garden variants, which is considered to cause genetic pollution of native H. non-scripta. Therefore, a conservation study is in progress, in which this diagnostic marker system for bluebells is applied.
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Barn i den digitala världenSvensson, Jesper January 2017 (has links)
Detta kandidatarbete handlar om hur skolan arbetar med digitaliseringen och hur de använder de digitala verktyg som finns. Det kommer handla om de övergångar digitaliseringen innebär för skolan och vad som kan vara hinder för skolan att digitaliseras. Kandidatarbetet kommer också ta upp vikten av vuxnas närvaro för de barnen som använder internet och blivit upprörda/besvärade av något som det sätt på internet. Den gestaltande delen av kandidatarbetet kommer att handla om barn som ännu inte börjat skolan. Barnen kommer att hjälpa till för att skapa sig en egen design på en applikation som de sedan skulle vilja använda. Barns vetskap om hur tekniken används är begränsad på ett positivt sätt som gör att de kan öppna upp för nya sätt att se tekniken. Barnen är villiga att använda tekniken och det spelar ingen roll om det skulle vara på ett papper eller digitalt. De gillar allra bäst närheten till vuxna när de får interagera med det som är framför dem. / This Bachelor Thesis is about how the school works with digitalization and how they use the digital tools that are available. It is about the transitions that digitalization faces that could prevent the school from becoming more digitized. The work will also address the importance of adult’s presence for the children's use of the internet and support them if they had a bad experienced on the internet. The output of the Bachelor Thesis will be about children who have not yet started school. The children will help to create their own design on an application that they would like to play with. Children's knowledge of how technology is used is limited in a positive way, that enables them to open up new ways to see the technology. Children are willing to use the technology and it doesn't matter if it is paper or digital. They enjoy the company of grownups when they interact with what's in front of them.
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An ecological life history of tall bluebell in UtahMatthews, Verl B. 01 May 1971 (has links)
The ecological life history of tall bluebell, Mertensia arizonica Green var. leonardi (Rydb.) Johnston (M. leonardi Rydb.), was investigated during 1963 and 1964. Summer field studies were conducted on the Mud Creek Sleep Allotment of the Uinta National Forest, Wasatch County, Utah. Laboratory and herbarium studies were carried out at Brigham Young University. Specific objectives were to investigate seed germination, seedling development, root system, phenology, palatability, and describe the physical site factors where bluebell occurred. A study of this species was necessary because much of the herbage produced in certain areas of aspen range is not utilized. This condition occurs when mature stems become infected with powdery mildew during mid-July, collapse onto the ground, and dry up. This plant also becomes the dominant forb under certain grazing conditions, and appears to crowd out other desireable forage species. This tall bluebell species occurs throughout the length of central to northern Utah and into southwestern Wyoming and southeastern Idaho, constituting up to 37.1 percent of the understory ground cover. The seed have impermeable seed coats with scarification resulting in a germination percentage of 0.0 to 26.0. Emergence percentages of 21.0 to 53.0 were obtained from field plantings. The period of greatest seedling mortality coincided with the development of permanent wilting conditions at the 6 and 12 inch soil depths during both summers of field study. Studies of transplanted seedlings show that 1 to 2 years of developmental growth are required prior to developing the first single flowering shoot. Mature root systems consist of a semi-fleshy "caudex" from which several main roots extend to a depth of 3 to 4 feet and terminate in fine roots extending beyond to a depth of about 7 feet. Numerous fine roots are concentrated in the upper 1 to 3 feet of soil. Variations in soil texture, structure, pH, total soluble salts, and percent organic matter were not found to alter the basic pattern of root development and distribution. Once plants are established, active growth of stems commences at time of snow melt, and continues 6 to 7 weeks when an average height of 19.5 to 31.0 inches has been reached. Stems elongate as much as 1.4 inches per day with a peak occurring midway in the growing period. Flowering begins about 4 weeks after snow melt and lasts 2 to 4 weeks. Mature seed are shed 18 to 28 days after flowers open. Temperature appears to constitute a significant factor of initial growth and flowering rates. Lodging of bluebell stems occurs with wilting or fast falling rain. The first severe wilting occurs between July 21 and August 13. This coincides with the occurrence of permanent wilting conditions at the 6 and 12 inch soil depths. Wilting is followed by maturation and drying of stems. The latter event is often associated with mildew infection caused by Erysiphe cichoracearum. The occurrence and rate of increasing infection appears favored by high temperature and low humidity. Sheep utilize bluebell up to 44 percent by mid-July. Cattle utilize bluebell up to 46 percent, while deer were not found to utilize bluebell at all. The pocket gopher, Thomomys talpoides was also observed to utilize bluebell stems and inflict injury to main roots.
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