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124 Uppsatser om Selective predation pigmentation - Sida 6 av 9

Avgasrening för framtida miljökrav

SammanfattningI dagens miljöfokuserade samhälle ställs det allt högre krav på den tunga fordonsindustrin varvid den gällande miljölagstiftningen skärpts i flera steg de senaste åren. Scania tillverkar tyngre fordon och motorer som alla måste följa de kommande utsläppskraven. Detta innebär att motorernas utsläpp måste reduceras varför avancerade efterbehandlingssystem har införts i ljuddämparen. En metod för att rena avgaserna från kväveoxider är SCR-teknologi (Selective Catalytic Reduction). Denna teknik bygger på att en urealösning sprutas in i avgasflödet.

Skillnader i migrationsframgång mellan vild och odlad laxsmolt (Salmo salar L.)

Laxen är en anadrom fiskart som reproducerar sig i sötvatten men lever huvuddelen av sitt vuxna liv i saltvatten. På grund av vattenkraftens dammbyggen hindras laxen att göra dessa habitatbyten och reproduktionen drabbas. För att kompensera för minskade laxstammar sätter vattenkraftbolagen varje år ut miljontals odlad laxsmolt i vattendrag som mynnar ut i östersjön. I Umeälven släpps 80000 laxsmolt ut årligen. Tidigare rapporter visar att överlevnaden hos dessa är lägre än hos vild smolt.

Den svenska lapphunden - en ras i behov av förändring?

Many pedigree dogs are suffering from inherited diseases or personality disorders caused by selective breeding. The Swedish lapphund is a breed that has been suffering from some loss of genetic variation due to the heavy use of only a few males. Concerns have arisen and crossbreeding has been discussed as a way to manage gene loss. Four breeds has been taken into consideration for this purpose; schipperke, finish lapphund, Norwegian buhund and Norwegian elkhound, black. These breeds has been tested theoretical by a comparison of mentality and health.

Effekt av habitat på täthetsdynamik mellan stensimpa och ung öring i svenska vattendrag

Öring (Salmo trutta) och stensimpa (Cottus gobio) är två vanligt förekommande arter i Sverige. En fråga som lyfts allt mer frekvent i olika artiklar och publikationer är hur dessa två arter påverkar varandra och vilka faktorer som påverkar denna interaktion. (Gabler & Amundsen 1999, Holmen et al. 2003, Elliot 2006, Hesthagen et al. 2010).

Rondellen och dess växtmaterial

Common species of freshwater mussels may, like the freshwater pearl mussel (Margaritifera margaritifera) have a drastic decline in number and there is several reasons, like sedimentation, a decline of host fishes, introduction of alien species, nutrition leakages from agriculture and pollutants of medic drugs and poison. Ann Gustavsson made in the year of 2007 a study over rejuventation of freshwater great mussels in nine watersystems and considered that the rejuventation within the populations were all along the line poor. This study orients from her work and points to determine if there is a connection between the poor juventation and pollution of nitrogen and phosphorous from industries and private sanitations. The study was performed with the software program ArcGIS9.2 to take out drainage areas for the concerned habitats and contact was made with the concerned authoritys. When it comes to supervision of private sanitations is it the countys and for industries is it the county administrative board.

Större och mindre växtätares samexistens : Möjlig interaktion och effekt på lokal biodiversitet

The purpose of this report was to investigate to which extent local presence of large herbivore mammals (Alces alces, Cervus elaphus, Capreolus capreolus, Dama dama and Sus scrofa) covaries with small rodents (Myodes glaerolus, Apodemus flavicollis and Apodemus sylvaticus? The hypothesis was that high abundance of wild ungulates would inhibit the density of small forest rodents. The data was collected during field work within FoMA (Environmental Monitoring Assessment)/SLU (Swedish University of Agricultural Science). The Ungulate dropping inventory and rodent trappings, which is the base in this report, where performed 2012 ? 2014 in Gnesta/Nyköping municipalities (G/N) with a relatively high density of wild ungulates and Vetlanda/Växjö municipalities (V/V) with relatively lower wild ungulate density.

Påverkar kallt och blött väder vid kläckning överlevnaden hos tjäderkycklingarna (Tetrao urogallus L.) i Sverige?

Tjäderpopulationen Tetrao urogallus L. har under det senaste årtiondet minskat i täthet i stora delar av sitt utbredningsområde. Det är därför viktigt att undersöka faktorerna som kan påverka tjäderns fortplantning och överlevnad. Det råder delade meningar kring den främsta orsaken till nedgången. De flesta är eniga om att klimatet har en påverkan, men samspel mellan olika faktorer och lokala förhållanden är oftast avgörande för hur stor denna påverkan blir.

Optimization and validation of a triplex real-time PCR assay for thermotolerant Campylobacter species associated with foodborne disease

The genus Campylobacter is globally recognised as the leading bacterial cause of human foodborne gastroenteritis. Every year around 8000 Swedes are infected by Campylobacter. Most people are infected by thermotolerant Campylobacter species, commonly C. jejuni and C. coli.

Migration losses of Atlantic salmon (Salmo salar L.) smolts at a hydropower station area in River Åbyälven, Northern Sweden : passage fates at a reservoir, a power house and a bypass structure

A large number of rivers in northern Sweden have hydropower developments that cause negative effects on both up- and downstream migrations of anadromous species like Atlantic salmon. So far, most attention has focused on the hindrances of adult fish during their upstream spawning migration. However, since turbines in power stations cause losses on downstream passing fish, the focus on negative effects on smolts has increased. The aim of this study was to compare three different causes of losses of salmon smolts passing downstream through a power station area in the flow-controlled River Åbyälven in northern Sweden.A total of 61 wild salmon smolts were caught and radio-tagged in the River Åbyälven during their downstream migration in June 2009. The salmon smolts were released at three locations, 1.1 km upstream from the power station, in the turbine intake and in the upper part of a fishway, acting both for up- and downstream fish passage.

PR i det dolda : en studie om Redaktionell PR

The fashion industry is a line of business which is characterised by tough competition. Often the consumer target groups exposed to advertisements identify them as attempts by the fashion industry to persuade them. When this happens, the consumer disregards the information due to selective attention. Faced with these conditions, companies need to find new, creative ways to market their product lines. This essay is about Public Relations, in particular Public Relations that appear in editorial spaces.

Finns det något samband mellan stormusslors (unionoida) föryngring och utsläpp i närheten av dess levnadsmiljö? : en jämförelse mellan vattendrag i Västra Götaland

Common species of freshwater mussels may, like the freshwater pearl mussel (Margaritifera margaritifera) have a drastic decline in number and there is several reasons, like sedimentation, a decline of host fishes, introduction of alien species, nutrition leakages from agriculture and pollutants of medic drugs and poison. Ann Gustavsson made in the year of 2007 a study over rejuventation of freshwater great mussels in nine watersystems and considered that the rejuventation within the populations were all along the line poor. This study orients from her work and points to determine if there is a connection between the poor juventation and pollution of nitrogen and phosphorous from industries and private sanitations. The study was performed with the software program ArcGIS9.2 to take out drainage areas for the concerned habitats and contact was made with the concerned authoritys. When it comes to supervision of private sanitations is it the countys and for industries is it the county administrative board.

Validation of Steins/Arla Foods method for lactate fermenting clostridia in milk

One of the most serious and economically important defects caused by clostridia in milk products is the late blowing of semi-hard cheeses.Clostridia occur naturally in soil and can contaminate milk through crops contaminated by dung and soil followed by a less successful silage process, that give them opportunity to grow unaerobically. When anaerobic conditions occur, such as storage of semi-hard cheese, they ferment lactic acid to butyric acid and the gases CO2 and H2.At the fusion of Arla and MD Foods, a series of changes were conducted on the MPN method for lactic acid fermentation for clostridia in milk. These changes resulted in an increased accuracy due to an increased number of test tubes and the change of media from MRCM to BBB, Bryant & Burkey Broth, that was thought to be more selective for Cl. tyrobutyricum, the organism mostly found in hard cheese. When the number of dairy farmers that were given quality reduction fines increased, the new method was suspected and a validation was conducted.The validation included inoculation of different clostridia and bacillus strains into BBB substrate and enzymatic testing of positive samples with Rapid ID 32A.

Synchronizing migration with birth: an exploration of migratory tactics in female moose

Migration and giving birth are crucial decisions for animals during their life cycle, which may have lasting consequences on their population demography and fitness. Migration can entail a variety of possible effects for an individual, such as access to high quality food and reduced risk for predation. The moose (Alces alces) in northern Sweden is partially migratory and moose females are known to give birth to one or two calves. The synchrony between time of calving and timing of migration has not been compared before, especially in terms of energy maximizing and time minimizing perspectives, which may provide vital cues for fitness benefits of migration. I investigated effect of timing of birth and individual life history on distance, timing, stopovers and duration of 190 individually marked female moose that have been tracked for multiple years in ten different areas in northern Sweden.

Bestämning av syntetiska cannabinoider med gaskromatografi-masspektrometri

This thesis has been performed at Clinical Chemistry at Sahlgrenska University Hospital in Gothenburg. The purpose of the project was to investigate new and alternative ways to determinate synthetic cannabinoids by gas chromatography-mass spectrometry. Currently, the possibilities to quantify synthetic cannabinoids are very limited. This can lead to an increased use of synthetic cannabinoids as the risk of detection is low, which may be known by drug users. The synthetic cannabinoids are sold mixed with different herbs and have varying names like Spice Gold, Spice Silver, K2, Smoke and Pot-pourri.The synthetic cannabinoids analyzed were JWH-018 and JWH-073, which are commonly found in seized Spice material.

Optimering av SNCR-system i en biobränsleeldad panna : möjligheter till minskade NOx-utsläpp för ENA Energi

Emission of nitrogen oxides as well as carbon monoxides is an inevitable result of combustion. A Swedish law "Law of environmental fee for emissions of nitrogen oxides as a result of energy production" (lagen om miljöavgift på utsläpp av kväveoxider vid energiproduktion (SFS 1990:613)) controls the emission of NOx from energy production by a system of fees. The system has resulted in a strong approach toward less emissions of NOx among the energy production plants. High emission levels, today exceeding 52 mg/MJsupplied fuel, leads to costs for energy production companies. This paper examines possibilities to reduce the emissions of NOx by optimization of the SNCR-technique in a biofuel fired heat and power plant.

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