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190 Uppsatser om Seed ageing - Sida 2 av 13

Faderskapsanalys av tallfrö från Västerhus fröplantage : Skillnad i pollenkontaminering mellan öppen pollinering och pollinering inom ett avgränsat system

In this study, pollen contamination (measured by the number of seeds pollinated by pollen not belonging to any of the clones on the seed orchard) is compared between open pollination and isolated pollination environments in a Scots pine (Pinus sylvestris) seed orchard called Västerhus, located outside Önsköldsvik. In this seed orchard a tent experiment is taking place. Skogforsk has built six large tents covering 12-14 trees with each tent. Fertilization patterns were compared between one tree in a tent with a supplementation of pollen from five clones not represented in the tent and another tree of the same clone subject to open pollination outside the tents. By using DNA markers the paternity was determined for 48 seeds from each tree.

Skogssådd med tall och gran : effekter av fröegenskaper och skärm/hygge på plantbildning, överlevnad och tillväxt de två första åren efter sådd

Over the past few years the Swedish forestry industry has become increasing interested in direct seeding. Although, in practice, this interest has been restricted to pine seed, the knowledge and techniques that have been developed for pine seeding can readily be transferred to spruce. Direct seeding is a method that is of interest to the forestry industry since it can lead to lower regeneration costs, denser stands and better root development than the more conventional planting method. This study evaluated experiments that focused on direct seeding of spruce in the northern Sweden. Skogforsk set-up the experiments in Gideå and Sävar in 2003.

Den åldrande befolkningens hot mot välfärden - En politisk myt i väst

The purpose of this thesis is to expose the political myth in the West about the ageing population seen as a threat against the welfare society. To do so I have described what a political myth is, and showed how it is presented in the most influential newspapers and organisations in the West. I have also presented alternative perspectives to the dominating view on the ageing population and it's impacts on welfare. In this way I have tried to point out that the subject has a political dimension. In the thesis last section I compare the message presented in the newspapers and the organisations with the characteristics of a political myth.

Internetbokhandelns rekommendationssystem : en undersökning av Amazon.coms Similar Items.

The aim of this thesis is to examine one part of Amazon.coms recommender systems: Similar Items. The purpose is also to show the difficulties with subject access, i. e. to find a similar book to the one you just read; problems with traditional systems versus the usefulness with recommender systems like Amazon.coms Similar Items. Similar Items presents a set, a cluster of related items to a given item based on customers co-purchase.

Alternativ för värme- och kylaförsörjning i planerade kontorsbyggnader på Arlanda

This thesis consider alternatives for heating and cooling planned office buildings at Arlanda airport. The thesis is divided into three parts where the third part is a shorter synthesis of the two first. In the first part the energy demands of the buildings are modelled in a computer program. Two different building models are created, one more conventional and one with good energy properties. The results shows that with proper construction and ventilation systems etc.

Syntes och karakterisering av katalytiska zeolitfilmer på inerta packningsmaterial.

Detta projektet syftar till att studera om syntes av katalytisk zeolitfilm på inerta packningsmaterial är möjlig. De packningsmaterial som har studerats sfärer med diametern 6 mm och porösa kroppar, båda dessa packningsmaterial innehåller huvudsakligen Al2O3. De zeoliter som har använts är ZSM-5 och Silkalit-1. Den metod som används för syntes av zeolitfilmen är "the Seed Film Method", för att kunna använda metoden har vissa modifieringar av den skett. Proven har karakteriserats med svepelektronmikroskopi, gasadsorption, röntgendiffraktion, dynamisk ljusspridning och termisk analys.

Effects of genotype, age and feed on the fat components of egg yolk

The aim of this study was to investigate if the hen?s genotype, age and diet affect fat components in egg yolk. The fat components measured were total fat content, phospholipids, cholesterol and the fatty acid profile. This trial involved 12 groups of laying hens housed in 8-hen cages enriched with perches, dust baths and nests. The genotype Lohmann Selected Leghorn (LSL) and the genotype Lohmann Brown (LB)was used.

Lärarstudenters erfarenheter av förhållandet mellan modersmål, identitet och inlärning

ABSTRACT Our main objective with this essay is to provide a description of old people?s stories about aging. The essay is based on the empirical source of four qualitative interviews with older people over the age of eighty years young. The main goal is to inquire answers about; their time in the workforce; retirements; healthissues; media/advertisements; adolescence/youthfulness and attitudes. The following main questions have been dealt with: What do the elderly emphasize when they describe ageing? Are healthissues the prime subjects the elderly talk about? Do the elderly experience positive or negative attitudes towards ageing? What is their point of view of younger generations? In what way do they describe their years as workers? In what way do they describe aspects about their retirement? We reserved to consider the opinion of their own, to be the most valuable source in our study.

Svampar associerade med raps : betydelse för uppkomst och grödetablering

Oilseed rape is an important crop in Sweden and is grown on about 90000 ha today. The interest in oil seed pro-duction is increasing because of growing demand and high prices for oil seed both in Sweden and Europe. However, an increased intensity in the oil seed production can bring higher risk of yield losses due to fungal diseases. The purpose of this study was to investigate what different fungi are associated with oilseed rape under field conditions and if their incidence is correlated to crop establishment problems. This study was carried out in three parts: 1) investigations on fungal community structure in roots and rhizosphere soils from young spring- and winter rape plants sampled in failed respectively good establishment patches in four fields, 2) investigations on the pathogenicity of fungi isolated from oilseed rape in controlled environment and 3) investigations on the effect of different fungicide seed treatments on germination and early plant development in a field soil naturally infested with damping off- and Verticillium wilt pathogens. The studies on community structure using a combined approach of standard fungal isolation techniques and DNA based methods revealed a high fungal diversity in three out of four studied fields of spring rape and winter rape. For some unknown reason, very few fungal species were identified from the fourth field.

Fröplacering vid hög såhastighet - Väderstad Rapid jämfört med Amazone Cirrus

In today's agriculture efficiency and the capacity of tools and machinery are crucial. In this work we investigate whether it is possible to enhance the capacity of sowing by increasing the work speed of seeders, how seed technology affects seed placement, and if there is any difference between two different brands of seeders and their sow techniques. The seeders we have chosen to compare are Väderstad Rapid drill and Amazon Cirrus drill. The tillage capacity of the seeders and their traction power needs were examined as well.Väderstad Rapid and Amazon Cirrus were tested in a randomized block design with four replicates at three different speeds, 8 km/h, 12 km/h and 15 km/h. The seed placement at the different speeds was examined by dividing the seedbed into four different zones from its surface to its bottom.

Skaftslamkrypa (Elatine hexandra) i Bolmen, utbredning, tillväxt, reproduktion och styrande faktorer

The plants in the genus Elatine are characteristic for oligo and mesotrophic lakes. This study focuses on Elatine hexandra one of the four species in Sweden. It is stated as vulnerable by the National Environment Agency and a conservation plan with guidelines to preserve the plant in Sweden is under preparation. There have been a few previous studies investigating this plant in other countries but this is the first one for Sweden. The aim of this study was to investigate the distribution, growth and reproduction of E.

Dynamisk kunskapsorganisation: teoretisk ansats och implementering

Knowledge organization is perceived as a central, constituting activity defining the notion of libraries. Critique calling for a new theoretical foundation voiced by active researchers within library and information science concerning the current knowledge organization has been utilized as a point of departure. Specifications concerning a new theoretical foundation implied by these critiques are considered within this thesis and theory found in The Order of Things by Michel Foucault proposed as an alternative theory for understanding knowledge organization as a human science where meaning, value and representation, by which the ordering of things is possible, is acknowledged as a result of human activity and history. Thus meaning, value and representation must be perceived as dynamic. An example of implementation of the proposed theory has been achieved by the use of bibliometrics.

Uppfångning och kvarhållning av 134Cs och 85Sr i olika växtutvecklingsstadier

Emissions of radionuclides to the atmosphere can lead to wet deposition on plants in the event of rainfall. An increased level of radioactivity in the plants may occur due to interception and retention of the radionuclides. If the content of the plants is above the threshold limit value, entire yields may have to be destroyed. In order to prevent contamination or decrease the content countermeasures can be taken. The impact of the biomass, leaf area index (LAI) and growth stage of the plant on the interception and retention is important to know in order to decide which countermeasures to use. Weather may also be an important factor. In this work the interception and retention of 134Cs and 85Sr by spring wheat, ley and spring oil-seed rape was studied.

Val av tidpunkt för markberedning vid naturlig föryngring under skärm av Pinus sylvestris i Svealand : Timing of scarification when using natural regeneration in seed tree stands of Pinus sylvestris in Central Sweden

This thesis is built on a field study that was carried out in two seed-tree stands near by Götbrunna in Uppland, Sweden. The aim was to examine if scarification carried out in spring time could generate a more dense seedling establishment when using natural generation, than scarification carried out in autumn. It was also investigated whether there were differences in mortality the first season between the two plot-types. Plots were established block-wise with 50 blocks (pairs) on each site. The spring scarification was made with a hoe during 22-23 of April.

Aquazol - ett åldringsbeständigt ämne?

Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Konservatorprogrammet15 hpInstitutionen för kulturvårdGöteborgs universitet2013:15.

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