Fakultet for biovitenskap, fiskeri og økonomi

"Bioactivity profile of barettin - With special focus on anti-inflammatory, antioxidant and anticoagulant activities"

Fri, 17 Apr 2015 00:00:00 GMT

Lind, Karianne Fredenfeldt
The diversity of the marine species inhabiting the oceans makes them highly interesting as potential sources of bioactive molecules for various applications. The extreme environment in the Barents Sea, in terms of temperature and light availability, have forced its organisms to adapt to their surroundings by developing unique biomolecules, and Arctic marine organisms are therefore an excellent starting point when searching for compounds with novel bioactivities. In this thesis, the focus has been on revealing potential antioxidant and anti-inflammatory effects of barettin, a compound originally isolated and described from the marine sponge Geodia barretti in 1986. Several papers have previously highlighted the strong anti-fouling properties of the molecule. In paper I, we presented novel antioxidant and anti-inflammatory properties of barettin. We found that barettin had strong dose-dependent antioxidant effect in both biochemical and cellular assays and follow-up experiments in an inflammatory cell model showed that barettin inhibited LPS-induced production of IL-1β and TNFα in a dose-dependent manner. The combination of the antioxidant and anti-inflammatory effects led us to explore barettin as a potent inhibitor of atherosclerosis development. In paper II, barettin was found to also inhibit LPS-induced production of MCP-1 in THP-1 cells, a chemokine strongly linked to monocyte recruitment and atherosclerosis. When THP-1 cells were co-stimulated with LPS and IL-4, IL-4 being a cytokine with pleiotropic effects, barettin increased the anti-inflammatory effect of IL-4. In paper II, we also presented a biochemical kinase inhibitory profile of barettin, showing inhibitory effect of three kinases, namely salt-inducible kinase 2 (SIK2), calcium/calmodulin-dependent kinase 1α (CAMK1α) and receptor-interacting protein kinase 2 (RIPK2), the two latter being involved in inflammatory processes. The inhibition observed on IL-1β production could be explained by the ability of barettin to inhibit RIPK2, as this kinase have a role in NF-κB activation and possibly also IL-1β maturation. The inhibitory effect of barettin on CAMK1α, which is involved in IL-10 regulation, probably result in an observed reduction of the anti-inflammatory cytokine IL-10 in THP-1 cells. In an ex vivo whole blood model stimulated with LPS, the effect of barettin on tissue factor (TF), TNFα, MCP-1, IL-10, TxB2, LTB4 and HMGB1 was evaluated (paper III). Barettin reduced TF, TNFα, TxB2, LTB4, MCP-1 and IL-10, whereas the effect on HMGB1 was modest. In summary, the overall results show that barettin affects several cellular processes and the effect of barettin should be further evaluated both in vitro and in vivo to find the true potential of the molecule.

Harbour seal Phoca vitulina movement patterns in the high-Arctic archipelago of Svalbard, Norway

Wed, 03 Sep 2014 00:00:00 GMT

Blanchet, Marie-Anne Ermeline; Lydersen, Christian; Ims, Rolf Anker; Lowther, Andrew D.; Kovacs, Kit
Harbour seals Phoca vitulina are mainly considered a temperate species, but the world’s northernmost population resides year-round in the high-Arctic archipelago of Svalbard. In this study we document post-moulting at-sea movements of 30 individuals from this population using satellite relay data loggers deployed in the autumns of 2009 and 2010. All of the seals showed a strong preference for the west side of the archipelago, staying mainly in coastal areas (<50 km over the continental shelf), but seldom entering the fjord systems. Distance swam per day, individual home range size, and trip duration increased throughout the winter to a peak that was reached when drifting sea ice in the region was at a maximum. No effect of age was observed, but sex differences were significant; males occupied larger areas than females. Habitat selection was quantified by modelling time spent in area (TSA) as a function of environmental parameters using Cox proportional hazard models (CPH). The harbour seals avoided heavy ice concentrations (>50%) but did occupy areas with substantial amounts of drifting ice (5 to 25%). Shallow water (<100 m) and steep bathymetric slopes were preferred to deep water or flat-bottom areas. Harbour seal distribution in Svalbard is largely restricted to coastal areas that are heavily influenced by Atlantic water brought northward in the West Spitsbergen Current; both the temperature and influx of this water type are predicted to increase in the future. It is thus likely that environmental conditions in Svalbard in the future will become more favourable for harbour seals.

Results based management in fisheries: Delegating responsibility to resource users

Fri, 31 Oct 2014 00:00:00 GMT

Nielsen, Kåre Nolde; Holm, Petter; Aschan, Michaela
While the notion of results based management has been devoted recent attention in the context of reforming European fisheries management, it remains unclear what it entails. A conceptual model of results based management in fisheries is proposed as a way for public authorities to delegate specific management and documentation responsibilities to resource users. The model comprises three defining features: (1) That authorities define measurable objectives for the utilization of fisheries resources; (2) that resource users are made responsible for achieving these objectives and for (3) providing documentation that allows for an audit of the extent to which they are met. Selected cases are used to illustrate these features. Rationales and prospects of introducing results based management as an alternative in a European fisheries management context are discussed, giving consideration to how it may be pursued under the reformed common fisheries policy.

Response of Methanogens in Arctic Sediments to Temperature and Methanogenic Substrate Availability

Wed, 17 Jun 2015 00:00:00 GMT

Blake, Lynsay; Tveit, Alexander Tøsdal; Øvreås, Lise; Head, Ian M.; Gray, Neil
Although cold environments are major contributors to global biogeochemical cycles, comparatively little is known about their microbial community function, structure, and limits of activity. In this study a microcosm based approach was used to investigate the effects of temperature, and methanogenic substrate amendment, (acetate, methanol and H2/CO2) on methanogen activity and methanogen community structure in high Arctic wetlands (Solvatnet and Stuphallet, Svalbard). Methane production was not detected in Stuphallet sediment microcosms (over a 150 day period) and occurred within Solvatnet sediments microcosms (within 24 hours) at temperatures from 5 to 40°C, the maximum temperature being at far higher than in situ maximum temperatures (which range from air temperatures of -1.4 to 14.1°C during summer months). Distinct responses were observed in the Solvatnet methanogen community under different short term incubation conditions. Specifically, different communities were selected at higher and lower temperatures. At lower temperatures (5°C) addition of exogenous substrates (acetate, methanol or H2/CO2) had no stimulatory effect on the rate of methanogenesis or on methanogen community structure. The community in these incubations was dominated by members of the Methanoregulaceae/WCHA2-08 family-level group, which were most similar to the psychrotolerant hydrogenotrophic methanogen Methanosphaerula palustris strain E1-9c. In contrast, at higher temperatures, substrate amendment enhanced methane production in H2/CO2 amended microcosms, and played a clear role in structuring methanogen communities. Specifically, at 30°C members of the Methanoregulaceae/WCHA2-08 predominated following incubation with H2/CO2, and Methanosarcinaceaeand Methanosaetaceae were enriched in response to acetate addition. These results may indicate that in transiently cold environments, methanogen communities can rapidly respond to moderate short term increases in temperature, but not necessarily to the seasonal release of previously frozen organic carbon from thawing permafrost soils. However, as temperatures increase such inputs of carbon will likely have a greater influence on methane production and methanogen community structure. Understanding the action and limitations of anaerobic microorganisms within cold environments may provide information which can be used in defining region-specific differences in the microbial processes; which ultimately control methane flux to the atmosphere.

A deliberative approach to valuation and precautionary management of cold water corals in Norway

Wed, 17 Jun 2015 00:00:00 GMT

Falk-Andersson, Jannike; Foley, Naomi; Armstrong, Claire W.; van den Hove, Sybille; van Rensburg, Thomas; Tinch, Rob
This paper explores management challenges in relation to human impacts on cold water corals (CWC) in Norway. CWC are a slow growing organism about which there is uncertainty regarding distribution and values. We discuss area closures to protect this environmental public good against destructive fishing practices. Focus groups were combined with questionnaires to inform precautionary management measures that can be used to protect known CWC as well as areas where CWC are thought to exist. The research finds that respondents believe CWC are valuable and should be protected, but that this requires information on their presence and importance. Furthermore, priorities for protecting CWC differed between group discussions and the questionnaire responses. Use-values, particularly habitat supporting fish production, dominated the focus group discussions, while non-use and intrinsic values were emphasised in the questionnaire responses. Respondents rejected the use of the precautionary measure of temporary closures to gain information on CWC presence. Reasons were costs to fishers, and the rejection of the premise that precautionary closures would prevent further damage. This study shows that both use- and non-use values are effective arguments motivating people to support policies for nature protection. However, they are not sufficient to motivate support for precautionary measures that would provide significant but uncertain benefits for known costs. To motivate support for precautionary policies, there is a need to communicate better the types of organisms, services and values that may be lost without protection.

Nest predation in birds of conservation concern. Case studies of monitoring and management.

Fri, 12 Jun 2015 00:00:00 GMT

Stien, Jennifer
In this thesis I have used a variety of study methods at different spatial and temporal scales to explore population processes and management of 2 bird species of conservation concern, common eider and Slavonian grebe, focusing particularly on the role of nest predation in declining populations. I have demonstrated the role of proximate and ultimate causes of nest loss in eider at 2 declining colonies and highlighted the negative effects of human disturbance on nesting success and the potential role of disturbance in decline at one of the colonies. Furthermore, using the stepwise approach of elucidating proximate and ultimate factors has indicated management actions that are highly likely to improve nesting success and may also play a significant role in halting the decline of the eider colonies. I have demonstrated the usefulness of combining investigation of focal species of conservation, Slavonian grebe and targeted invasive alien predator species, American mink in order to optimise management decisions when knowledge of both species is poor. I have further demonstrated the regional decline of Slavonian grebe at the northern range of its distribution. Finally, by investigating the level of mink hunting in Norway I have demonstrated that collaborative control programs that include volunteer mink hunters are best focused on hotspots of conservation concern. I view this thesis as an example of adaptive protocols for learning by doing. In contrast to common (mis)conceptions, I have demonstrated that this approach can be undertaken with relatively little funding and resource use and is simple in its design. Thus, conservation management in general, and game management particularly in Norway should be more willing to tackle management challenges using this adaptive protocol approach.

Replacement of fishmeal with alternative proteins in diets for Atlantic salmon (Salmo salar L.): A study on the microbiota, morphology and function of the intestine

Tue, 16 Jun 2015 00:00:00 GMT

Hartviksen, Mali Anja Bjerkhaug
The research presented in this thesis aims to gain knowledge on the impact of a variety of alternative feed ingredients for which there is an increasing use for in Atlantic salmon feed. In focus were effects on the community population and metabolism of intestinal microbiota, its ability to compete with pathogens, gut physiology and health as well as fish performance and feed utilization. The results of the study revealed that the autochthonous microbiota was dominated by Corynebacteriaceae and the allochthonous microbiota was dominated by Lactobacillaceae regardless of diet, indicating a more stable intestinal microbiota than previously reported. Furthermore, results indicate that Atlantic salmon has the ability to compensate for low digestible feed ingredients by increasing the specific activity of leucine aminopeptidase and as such provide growth following feeding with feather meal close to that of fishmeal. By using ex vivo exposure of the intestine to pathogen bacteria, the effect of alternative feed ingredients was also investigated for their potential to make the host more susceptible to disease through intestinal invasion. The result from this trial revealed that use of alternative feed ingredients may intensify the damage resulting from the exposure of pathogen bacteria, but also that these damages can be alleviated by pre-exposing the intestine to probiotic bacteria. In conclusion pea protein concentrate and poultry by-product are highly useful for use as fishmeal replacements, soy protein concentrate and extracted sunflower should be used with caution due to potentially negative effects on the digestive physiology and feather meal merits further study due to its potential to modulate the digestive enzyme activity.
Papers number I and II in this thesis are not available in Munin:
I: M. Hartviksen, J.L.G. Vecino, E. Ringø, A.-M. Bakke, S. Wadsworth, Å. Krogdahl, K. Ruohonen, A. Kettunen: 'Alternative dietary protein sources for Atlantic salmon (Salmo salar L.) effect on intestinal microbiota, intestinal and liver histology and growth', available in Aquaculture Nutrition, 20, 381-398
II: Mali Hartviksen, Anne Marie Bakke, José G. Vecino, Einar Ringø, Åshild Krogdahl: 'Evaluation of the effect of commercially available plant and animal protein sources in diets for Atlantic salmon (Salmo salar L.): Digestive and metabolic investigations', available in Fish Physiology and Biochemistry, 40, 1621-1637

Antecedents and consequences of word of mouth - Consumer evaluation context, individualism, personality and defense of companies

Wed, 03 Jun 2015 00:00:00 GMT

Wien, Anders Hauge
People often share word of mouth (WOM) with their friends, family, and colleagues, and they increasingly also share WOM with strangers through various Internet channels. Since WOM has been found to have an important impact on consumer behavior, businesses worldwide are eager to understand the intricacies of the phenomenon. In particular, businesses are interested in understanding how positive WOM can be stimulated and how negative WOM can be stopped. This dissertation presents four papers that extend the current knowledge on these two issues. The first paper tests the effects of perceived quality and satisfaction on positive WOM intentions in both transaction-specific and cumulative evaluative contexts. Results reveal that different factors drive positive WOM intentions, depending on the context of the study. When consumers’ evaluations are related to a specific transaction, perceived quality is the dominating predictor of positive WOM intentions. When the evaluations are cumulative, satisfaction is the dominating predictor of positive WOM intentions. The second paper examines the relationship between individualism and WOM and factors moderating this relationship. The results reveal that high-individualism consumers are more willing than low-individualism consumers to transmit WOM in relation to satisfactory (versus unsatisfactory) consumption experiences, when WOM is unsolicited (versus solicited) and when the context involves high perceived social risk (versus low perceived social risk). These moderating effects may indicate that self-enhancement is the underlying motive in the relationship between individualism and WOM. The third paper tests a model of personality trait predictors of WOM tendency. The model includes two situational personality traits: social and personal consumer confidence, and two fundamental personality traits: extraversion and neuroticism. The results show that higher levels of extraversion result in greater social consumer confidence, which again has a positive effect on WOM tendency. Moreover, higher levels of neuroticism result in lower personal consumer confidence, which again has a negative effect on the tendency to engage in WOM. The results also show that social consumer confidence partially mediates the relationship between extraversion and WOM, whereas personal consumer confidence fully mediates the relationship between neuroticism and WOM. The fourth paper explores consumer responses to negative WOM on the Internet. The objective was to test an a priori belief that many consumers defend companies in response to an initial negative WOM utterance. Results of a netnographic study confirm that the online defense phenomenon does exist. A typology of six defensive styles (advocating, justifying, vouching, stalling, trivializing, and doubting) was developed and the characteristics of each defense described. Furthermore, factors influencing consumers’ choices of defense styles were identified. The study also highlights the different outcomes of the various defense styles and illustrates that this consumer phenomenon can be effective in preventing the spread of negative WOM or in mitigating its impact.
The papers of this thesis are not available in Munin:
1: Wien, A.H. and Olsen, S.O: 'Evaluation context’s role in driving positive word-of-mouth intentions', available in Journal of Consumer Behaviour, Vol. 11 No. 6, pp. 504–511
2: Wien, A.H. and Olsen, S.O: 'Understanding the relationship between individualism and word of mouth: A self-enhancement explanation', available in Psychology & Marketing, Vol. 31 No. 6, pp. 416–425
3: Wien, A.H. and Olsen, S.O: 'Personality and word of mouth: The mediating role of consumer self-confidence'. Submitted to the Journal of Consumer Marketing, not yet published.
4: Colliander, J. and Wien, A.H: 'Trash talk rebuffed: consumers’ defense of companies criticized in online communities', available in European Journal of Marketing, Vol. 47 No. 10, pp. 1733–1757

Årsregnskapets informasjonskvalitet i små aksjeselskaper: gjør ekstern kompetanse og kontroll en forskjell?

Sun, 31 May 2015 00:00:00 GMT

Olsen, Hanne Sofie Seljebu; Larsen, Silje Anett
I Norge kan en person alene eie og lede et aksjeselskap, ved at han eller hun utgjør hele generalforsamlingen, styret og daglig leder (heretter kalt enpersonsselskap). Formålet med oppgaven er å finne ut hvorvidt eksterne personer i forhold til en slik eneeier og -leder vil kunne bidra med kompetanse og kontroll slik at årsregnskapets informasjonskvalitet blir bedre. Disse eksterne personene kan være revisor, ekstern regnskapsfører eller eksterne personer innad i foretakets ledelse. Oppgavens problemstilling er: ”Hvilken betydning har bruk av ekstern kompetanse og kontroll for årsregnskapets informasjonskvalitet i små aksjeselskaper?” Oppgaven definerer årsregnskapets informasjonskvalitet som ”i hvilken grad en samling av iboende egenskaper oppfyller informasjonskravene til årsregnskapet som er gitt i regnskapsloven.” For å undersøke nivå av informasjonskvalitet ble det utarbeidet et måleinstrument bestående av 25 sjekkpunkter med tilhørende poengskala på 0- 0,5 – 1 poeng for hvert punkt. Undersøkelsen ble gjennomført ved å måle årsregnskapets informasjonskvalitet til 80 små nyetablerte aksjeselskaper i Troms for regnskapsåret 2013. Deretter ble det utført sammenligninger for å finne ut om ekstern kompetanse og kontroll bidro til bedre informasjonskvalitet. Først sammenlignet vi informasjonskvaliteten til foretak med og uten regnskapsfører og/eller revisor. Vi sammenlignet deretter informasjonskvalitet for å finne ut hvilken type hjelp som er best; revisor, regnskapsfører eller begge deler? Til slutt gjorde vi en rekke sammenligner med hensyn på foretakenes ledelsesmessige karakteristikker for å finne ut om eksterne personer innad i foretakets ledelse førte til bedre informasjonskvalitet. Vi testet om gjennomsnittene av informasjonskvalitet er statistisk forskjellige ved hjelp av t-test i Microsoft Excel. Resultatene fra undersøkelsen indikerer at bruk av regnskapsfører og/eller revisor bidrar til bedre informasjonskvalitet. Revisor bidrar tilsynelatende til best kvalitet på årsberetningen. For øvrig kan vi ikke dra konklusjoner om hvilken type hjelp som er best. Funnene fra undersøkelsen gir ikke klare indikasjoner på hvorvidt eksterne i foretakets ledelse fører til bedre eller verre informasjonskvalitet. Foretakene som hadde andre medlemmer i styret enn aksjeeiere fikk noe høyere informasjonskvalitet, men en t-test påviste at forskjellen ikke var statistisk signifikant. Samtidig hadde selskap med flere styremedlemmer, der styreleder og daglig leder ikke var samme person og som ikke var enpersonsselskap lavere informasjonskvalitet, noe som var i strid med våre forventninger. Også her var forskjellene så små at de heller ikke var statistisk signifikant. Derfor kan vi ikke kan dra sikre konklusjoner om eksterne i ledelsen øker eller svekker informasjonskvalitet. Resultatene gir dermed delvis klare og uklare svar på problemstillingen. Det som kommer tydeligst frem er at ekstern kompetanse og kontroll i form av revisor og/eller regnskapsfører bidrar til høyere informasjonskvalitet. Svaret er ikke like åpenbart når det kommer til ekstern kompetanse og kontroll i selskapets ledelse. Vår undersøkelse kan indikere at eksterne i ledelsen ikke har tilført selskapene bedre informasjonskvalitet i årsregnskapet. Nøkkelord: Årsregnskap, informasjonskvalitet, informasjonskrav, rapportering, årsberetning, noter, små foretak, revisor, ekstern regnskapsfører, aksjeselskaper.

Egne merkevarer og makt i dagligvarebransjen. Kjedenes bruk av egne merkevarer for å styrke egen maktposisjon

Fri, 29 May 2015 00:00:00 GMT

Løvland, Anne
Den norske dagligvarebransjen er et maktspill med mye makt på få hender, der en opplever at konkurransen mellom paraplykjedene i større grad handler om å kontrollere kostnadsstrukturen og profittfordeling mellom de ulike leddene i verdikjeden. Et av de viktigste utviklingstrekkene i den norske dagligvarebransjen er kjedenes introduksjon av egne merkevarer, og det kan tenkes at det er en sammenheng mellom kjedenes bruk av egne merkevarer og maktfordelingen i næringen. Denne oppgaven har som hensikt å se på den vertikale konkurransesituasjonen i den norske verdikjeden for mat. Tema for oppgaven vil derfor være å undersøke hvordan kjeder bruker egne merkevarer som et forhandlingsverktøy i forhandlinger med merkevareleverandører for å øke innflytelsen på innkjøpspriser. Det vil bli gjort en teoretisk tilnærming til problemstillingen, der det hovedsakelig vil bli benyttet teori basert på enkle forhandlinger mellom aktører. I analysen skal vi blant annet se at størrelsen på butikkjedenes prissensitive kundemasse er avgjørende for hvor stor trussel kjedenes egne merkevarer er mot kjente merkevarer. Kvalitetsforbedringer gjennom bruk av premium EMV er også av betydning for konkurransen med leverandører da denne varegruppen er et fullverdig supplement og er i direkte konkurranse med merkevarer, der kjedenes EMV tar markedsandeler fra den lojale kundebasen til kjente merkevarer. Utbredelsen av premium EMV er også gjennom kjedenes portvaktmakt videre med på å troverdiggjøre trusler om utestengelse av merkevareleverandører. Vi skal også se at kjeder utnytter markedsspesifikke karakteristikker, der de bruker antall innkjøpspunkt og konkurransen om hylleplass for å sette leverandører opp mot hverandre slik at de kan påvirke den relative forhandlingsmakten mellom aktørene. På bakgrunn av funn gjort i denne utredningen bør handelsnæringen etterspørre en lovfestet handelsskikk for å fjerne urimelig forretningspraksis, der en tar hensyn til forbrukernes interesser på sikt med tanke på pris, vareutvalg og kvalitet.