Sigaretter, snus og status: om livstilssforskjeller mellom brukergrupper av ulike tobakksprodukter

Røyking har i løpet av noen tiår gått fra å være en utbredt vane til å bli en avvikerhandling, og dagens tobakkspolitikk preges av løpende denormalisering av alle former for tobakksbruk. Likevel fortsetter mange å bruke tobakk. Artikkelen belyser en mulig kulturell forklaring på dette: Ulike tobakksprodukter og forskjellige bruksmåter inngår i livsstiler med ulik status og prestisje i befolkningen og har derfor ulik legitimitet. Med teoretisk utgangspunkt i Bourdieus kultursosiologi, viser jeg at de empiriske forskjellene i sosiokulturelle praksiser (inkludert tobakksbruk) kommer til uttrykk i et helhetlig og strukturert "rom for livsstiler", som gjennom homologier er koplet til strukturen i det objektive "rommet for sosiale posisjoner". Innholdet i de ulike livsstilene legger grunnlaget for de kulturelle distinksjonsforskjellene som settes i omløp i forbindelse med tobakksbruk

Isolation and Characterization of Novel Planctomycetes from Svarthammarhola Ice Cave with Potential for Production of Bioactive Molecules

Postponed access: the file will be accessible after 2019-06-01Planctomycetes represent a phylum of bacteria that possess peculiar characteristics. These include reproduction by budding, crateriform structures, rosette formation and an intricate cellular plan. They are considered important contributors in the global carbon and nitrogen cycle and have in recent years been proposed to have potential for various biotechnological applications. The Planctomycetes are ubiquitous bacteria, and has been reported in diverse and extreme environments, both terrestrial and aquatic. These extreme environments include cave ecosystems, as well as ice and glacier ecosystems. However, these reports have been based solely on molecular studies, and no Planctomycetes have been described in axenic culture from either cave or frozen environments. In this study the presence of Planctomycetes in perennial ice from the Svarthammarhola ice cave is elucidated. Drilled ice cores from the distinct layered ice mass were collected. Thawed ice was used as inoculum in enrichments for isolation of Planctomycetes strains. Isolated strains were then subjects for characterization, utilizing molecular and cultivation-based techniques. Four Planctomycetes strains were obtained in axenic culture, and all strains showed both morphological and physiological differences. Phylogenetic analyses of the strains’ 16S rRNA gene revealed that 3 of the strains shared phylogenetic similarities of 99 and 98%, and their closest described species was 90% similar. The fourth strain was 88 and 87% similar towards the other strains, and displayed 90% similarity towards its closest described relative, thus the isolated strains represent two novel genera, within the phylum Planctomycetes. To elucidate the strains’ ability to produce bioactive molecules, two of the strains were screened against the two cancerous cell lines Molm13 and PC3, as well as the normal healthy rat kidney cell line, NRK. Aqueous and organic compounds were extracted from cell cultures and used to treat the cell lines for 72 hours. The cell lines were then investigated for apoptosis induced by the extracts. The screening revealed that the strains were able to produce compounds with intermediate cytotoxicity towards the human AML cell line Molm13. Thus, displaying that the strains might be able to produce bioactive molecules that provide advantages towards other organisms competing for resources in their indigenous environment.Masteroppgave i biologiMAMN-BIOBIO39

Seafloor depth estimation by means of interferometric synthetic aperture sonar

The topic of this thesis is relative depth estimation using interferometric sidelooking sonar. We give a thorough description of the geometry of interferometric sonar and of time delay estimation techniques. We present a novel solution for the depth estimate using sidelooking sonar, and review the cross-correlation function, the cross-uncertainty function and the phase-differencing technique. We find an elegant solution to co-registration and unwrapping by interpolating the sonar data in ground-range. Two depth estimation techniques are developed: Cross-correlation based sidescan bathymetry and synthetic aperture sonar (SAS) interferometry. We define flank length as a measure of the horizontal resolution in bathymetric maps and find that both sidescan bathymetry and SAS interferometry achieve theoretical resolutions. The vertical precision of our two methods are close to the performance predicted from the measured coherence. We study absolute phase-difference estimation using bandwidth and find a very simple split-bandwidth approach which outperforms a standard 2D phase unwrapper on complicated objects. We also examine advanced filtering of depth maps. Finally, we present pipeline surveying as an example application of interferometric SAS

Dialogue Café - Bringing up Ideas in Collegial Teams

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Effekten av stressfaktorer i matkjeden på Listeria monocytogenes

The work presented in this thesis was carried out at Section for Food Bacteriology, Unit Food Safety, Antimicrobial Resistance and Zoonoses, Research section for Food Safety and Animal Health at the Veterinary Institute and Department of Paraclinical Sciences at the Faculty of Veterinary Medicine NMBU in Oslo. The work was carried out between 2014 and 2019.Listeria monocytogenes is the causative agent of food-borne listeriosis, a disease often transmitted by contaminated Ready-To-Eat (RTE) food. Immunosuppressed individuals, fetuses, and the elderly are at higher risk of developing a lethal form of listeriosis. Despite preventive actions taken against L. monocytogenes contamination of food, human listeriosis is still a food safety challenge. L. monocytogenes is a robust ubiquitous soil bacterium that is highly resistant to several stressors in the food chain, from farm to the human host. It is therefore difficult to eradicate it from raw food material and food processing environments. However, avoiding contamination and subsequent inhibiting growth of the bacterium in the food are important and highly prioritized preventive measures taken by the food industry. L. monocytogenes’ ability to persist in the food environment and to cause severe disease makes it a costly foodborne pathogen to control both in the food industry and in the society. This PhD project has explored how L. monocytogenes copes with a selected set of stressors present in the food, in the environment and in the human host, focusing on the aim of increasing food safety.L. monocytogenes er årsaken til matbåren listeriose, en sykdom som ofte er forårsaket av spiseklar mat (Ready-To-Eat, RTE) som er forurenset med L. monocytogenes. Individer med nedsatt immunforsvar, fostre og eldre har høyere risiko for å få listeriose med dødelig utfall. Til tross for forebyggende tiltak mot L. monocytogenes i mat, er listeriose hos mennesker fortsatt en utfordring for mattryggheten. L. monocytogenes er en robust bakterie som finnes nesten overalt og som er svært resistent mot mange stressfaktorer i matkjeden. Den er derfor vanskelig å eliminere fra råvarer og fra matproduskjonsmiljøer. Til tross for dette er det høyt prioritert av matindustrien å iverksette forebyggende tiltak for å redusere forurensning med L. monocytogenes og påfølgende vekst av denne bakterien i matproduktene. L. monocytogenes evne til å persistere i miljøet og dens evne til å forårsake alvorlig sykdom gjør at den er en kostbar matbåren bakterie for både matindustrien og for samfunnet. Med mål om å styrke mattryggheten har dette PhD prosjektet undersøkt hvordan L. monocytogenes håndterer ulike stressfaktorer som finnes i mat, i miljøet og i mennesket som vertsorganisme.Veterinærinstitutte

Do actions speak louder than words? - Communication and partner choice in the prisoner's dilemma game

Communication has been shown to enhance cooperation (Dawes, McTavish and Shaklee 1977; Isaac and Walker 1988; Sally 1995; Bochet, Page and Putterman 2006). But do all people benefit equally from communication? This thesis experimentally investigates two main research questions. First, how does chat room communication affect cooperation between two individuals in a social dilemma? Second, are individuals with different cooperative dispositions affected differently by communication? I also explore how potential partners use language to affect each other’s behaviour. I conduct an experiment to answer these questions. The experiment consists of three parts. In the first part, I elicit subjects’ cooperative dispositions. In the second part, I study participants’ cooperative behaviour in a two-person repeated prisoner’s dilemma. All subjects are randomly placed in potential pairs of two. Each subject may choose to form a mutual partnership with the other person before engaging in the prisoner’s dilemma. Half of the pairs may communicate with each other through a chat room prior to the partner choice. In the third and final part of the experiment, I re-elicit subjects’ cooperative dispositions. Results show that communication does not increase the overall probability of successfully forming a mutual partnership or subjects’ overall payoff. However, subjects’ average contributions are higher when they may communicate with their potential partner. More specifically, subjects classified as Cooperators in the first part of the experiment contribute significantly more when able to communicate, compared to Cooperators who cannot. Free Riders who may communicate are more likely to form mutual partnerships and they earn a higher payoff than Free Riders who may not communicate. The experiment is computerized using the experimental program z-Tree 3.6.7 (Fischbacher 2007). Results are analysed using the statistical software STATA/IC 14.2 and Microsoft Excel 16.12.MasteroppgåveECON39

Quantification of fucoidan isolated from Laminaria hyperborea using two different colorimetric assays and qNMR method

In this thesis, a colorimetric heparin assay and quantitative NMR (qNMR) are used for fucoidan quantification and compared against an established colorimetric enzymatic L-fucose assay.Masteroppgave i kjemiKJEM399MAMN-KJE