1000 resultados para Åbo Akademi
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Predation is an important selective force that has led to the evolution of a variety of fascinating anti-predator adaptations, such as many types of protective coloration and prey behaviours. Because the evolution of life has begun in the aquatic environment and many anti-predator adaptations are found already in relative primitive taxa, it is likely that many of these adaptations evolved initially in the aquatic environment. Yet, there has been surprisingly little research on the mechanisms and function of antipredator adaptations in aquatic systems. To understand the function of anti-predator adaptations and natural selection imposed on prey appearance and behaviour, I have investigated how protective coloration can be used, either as such or together with behavioural adaptations, to manipulate predator behaviour and decrease predation risk. To this end I conducted a series of behaviour ecological laboratory experiments in which I manipulated the visual appearance of artificial backgrounds and prey items. In paper I of this thesis, I investigated background choice as an anti-predator strategy, by observing the habitat choice of the least killifish (Heterandria formosa) between pairs of artificial backgrounds, both in the presence and absence of predation threat. It has been suggested that prey could decrease their risk of being detected by predators either by preferring backgrounds into which they blend or by preferring visually complex backgrounds. The least killifish preferred a background that matched their patterning to a background that mismatched it, showing that they are able to respond to cues of visual similarity between their colour pattern and the surrounding environment. Interestingly however, in female least killifish visual complexity of the background was a more important cue for habitat safety and may override or act together with background matching when searching for a safe habitat. It is possible that in females, preference for visually complex backgrounds is associated with lower opportunity costs than preference for matching backgrounds would be. Generally, the least killifish showed stronger preference while under predation threat, indicating that their background choice behaviour is an antipredator adaptation. Many aquatic prey species have eyespots, which are colour patterns that consist of roughly concentric rings and have received their name because they for humans often resemble the vertebrate eye. I investigated the anti-predator function of eyespots against predation by fish in papers II, III and IV. Some eyespots have been suggested to benefit prey by diverting the strikes of predators away from vital parts of the prey body or towards a direction that facilitates prey escape. Although proposed over a century ago, the divertive effect of eyespots has proven to be difficult to show experimentally. In papers II and III, I tested for divertive effect of eyespots towards attacking fish by presenting artificial prey with eyespots to laboratory reared three-spined sticklebacks (Gasterosteus aculeatus). I found that eyespots strongly influenced the behaviour of attacking sticklebacks and effectively drew their strikes towards the eyespots. To further investigate this divertive effect and whether the specific shape of eyespots is important for it, I tested in paper III the response of fish also to other markings than eyespots. I found that eyespots were generally more effective in diverting the first strikes of attacking fish compared to other prey markings. My findings suggest that the common occurrence of eyespots in aquatic prey species can at least partly be explained by the divertive effect of the eyespot shape, possibly together with the relative simple developmental mechanisms underlying circular colour patterns. An eyebar is a stripe that runs through the eye, and this pattern has been suggested to obscure the real eyes of the prey by visually blending parts of the eyes and head of the prey and by creating false edges. In paper III, I show that an eyebar effectively disrupts an eyelike shape. This suggests that eyebars provide an effective way to conceal the eyes and consequently obstruct detection and recognition of prey. This experiment also demonstrates that through concealment of the eyes, eyebars could be used to enhance the divertive effect of eyespots, which can explain the common occurrence of eyebars in many species of fish that have eyespots. Larger eyespots have been shown to intimidate some terrestrial predators, such as passerine birds, either because they resemble the eyes of the predator’s own enemy or because highly salient features may have an intimidating effect. In papers II and IV, I investigated whether the occurrence of eyespots in some aquatic prey could be explained by their intimidating effect predatory fish. In paper IV, I also investigated the reason for the intimidating effect of eyelike prey marks. In paper II, I found no clear intimidating effect of eyespots, whereas in paper IV, using a different approach, I found that sticklebacks hesitated to attack towards eyelike but not towards non-eyelike marks. Importantly, paper IV therefore presents the first rigorous evidence for the idea that eye mimicry, and not merely conspicuousness, underlies the intimidating effect. It also showed that the hesitation shown by fish towards eyelike marks is partly an innate response that is reinforced by encounters with predators. Collectively, this thesis shows that prey colour pattern and the visual appearance of the habitat influence the behaviour of fish. The results demonstrate that protective coloration provides numerous distinctive ways for aquatic prey to escape predation. Thus, visual perception and behaviour of fish are important factors shaping the appearance and behaviours of aquatic prey.
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Den här avhandlingen är en del av projektet Skolan i rörelse, vars mål är att kartlägga ungas fysiska aktivitet och öka ungas fysiska aktivitet under skoldagen. Syftet med den här avhandlingen är att undersöka motiv till fysiska aktivitet och inaktivitet bland elever i årskurs 7 till 9. I alla forskningsfrågor undersöks skillnader mellan könen och i forskningsfråga två och fyra undersöks skillnader över tid. För att bättre synliggöra våra resultat har vi valt att använda oss av motivfaktorer. En motivfaktor är i vårt fall en gruppering av enskilda motiv som mäter samma dimension.
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Tankyrases belong to the Diphtheria toxin-like ADP-ribosyltransferase (ARTD) enzyme superfamily, also known as poly(ADP-ribose) polymerases (PARPs). They catalyze a covalent post-translational modification reaction where they transfer ADP-ribose units from NAD+ to target proteins. Tankyrases are involved in many cellular processes and their roles in telomere homeostasis, Wnt signaling and in several diseases including cancers have made them interesting drug targets. In this thesis project, selective inhibition of human tankyrases was studied. A homogeneous fluorescence-based assay was developed to screen the compound libraries. The assay is inexpensive, operationally easy, and performs well according to the statistical analysis. Assay suitability was confirmed by screening a natural product library. Flavone was identified as the most potent inhibitor in the library and this motivated us to screen a larger flavonoid library. Results showed that flavones were indeed the best inhibitor of tankyrases among flavonoids. To further study the structure-activity relationship, a small library of flavones containing single substitution was screened and potency measurements allowed us to generate structure-activity relationship. Compounds containing substitutions at 4´-position were more potent in comparison to other substitutions, and importantly, hydrophobic groups improved isoenzyme selectivity as well as the potency. A flavone derivative containing a hydrophobic isopropyl group (compound 22), displayed 6 nM potency against TNKS1, excellent isoenzyme selectivity and Wnt signaling inhibition. Protein interactions with compounds were studied by solving complex crystal structures of the compounds with TNKS2 catalytic domain. A novel tankyrase inhibitor (IWR-1) was also crystallized in complex with TNKS2 catalytic domain. The crystal structure of TNKS2 in complex with IWR-1 showed that the compound binds to adenosine site and it was the first known ARTD inhibitor of this kind. To date, there is no structural information available about the substrate binding with any of the ARTD family members; therefore NAD+ was soaked with TNKS2 catalytic domain crystals. However, analysis of crystal structure showed that NAD+ was hydrolyzed to nicotinamide. Also, a co-crystal structure of NAD+ mimic compound, EB-47, was solved which was used to deduce some insights about the substrate interactions with the enzyme. Like EB-47, other ARTD1 inhibitors were also shown to inhibit tankyrases. It indicated that selectivity of the ARTD1 inhibitors should be considered as some of the effects in cells could come from tankyrase inhibition. In conclusion, the study provides novel information on tankyrase inhibition and presents new insight into the selectivity and potency of compounds.
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The iron and steelmaking industry is among the major contributors to the anthropogenic emissions of carbon dioxide in the world. The rising levels of CO2 in the atmosphere and the global concern about the greenhouse effect and climate change have brought about considerable investigations on how to reduce the energy intensity and CO2 emissions of this industrial sector. In this thesis the problem is tackled by mathematical modeling and optimization using three different approaches. The possibility to use biomass in the integrated steel plant, particularly as an auxiliary reductant in the blast furnace, is investigated. By pre-processing the biomass its heating value and carbon content can be increased at the same time as the oxygen content is decreased. As the compression strength of the preprocessed biomass is lower than that of coke, it is not suitable for replacing a major part of the coke in the blast furnace burden. Therefore the biomass is assumed to be injected at the tuyere level of the blast furnace. Carbon capture and storage is, nowadays, mostly associated with power plants but it can also be used to reduce the CO2 emissions of an integrated steel plant. In the case of a blast furnace, the effect of CCS can be further increased by recycling the carbon dioxide stripped top gas back into the process. However, this affects the economy of the integrated steel plant, as the amount of top gases available, e.g., for power and heat production is decreased. High quality raw materials are a prerequisite for smooth blast furnace operation. High quality coal is especially needed to produce coke with sufficient properties to ensure proper gas permeability and smooth burden descent. Lower quality coals as well as natural gas, which some countries have in great volumes, can be utilized with various direct and smelting reduction processes. The DRI produced with a direct reduction process can be utilized as a feed material for blast furnace, basic oxygen furnace or electric arc furnace. The liquid hot metal from a smelting reduction process can in turn be used in basic oxygen furnace or electric arc furnace. The unit sizes and investment costs of an alternative ironmaking process are also lower than those of a blast furnace. In this study, the economy of an integrated steel plant is investigated by simulation and optimization. The studied system consists of linearly described unit processes from coke plant to steel making units, with a more detailed thermodynamical model of the blast furnace. The results from the blast furnace operation with biomass injection revealed the importance of proper pre-processing of the raw biomass as the composition of the biomass as well as the heating value and the yield are all affected by the pyrolysis temperature. As for recycling of CO2 stripped blast furnace top gas, substantial reductions in the emission rates are achieved if the stripped CO2 can be stored. However, the optimal recycling degree together with other operation conditions is heavily dependent on the cost structure of CO2 emissions and stripping/storage. The economical feasibility related to the use of DRI in the blast furnace depends on the price ratio between the DRI pellets and the BF pellets. The high amount of energy needed in the rotary hearth furnace to reduce the iron ore leads to increased CO2 emissions.
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Många kvantitativa problem från vitt skilda områden kan beskrivas som optimeringsproblem. Ett mått på lösningens kvalitet bör optimeras samtidigt som vissa villkor på lösningen uppfylls. Kvalitetsmåttet kallas vanligen objektfunktion och kan beskriva kostnader (exempelvis produktion, logistik), potentialenergi (molekylmodellering, proteinveckning), risk (finans, försäkring) eller något annat relevant mått. I min doktorsavhandling diskuteras speciellt icke-linjär programmering, NLP, i ändliga dimensioner. Problem med enkel struktur, till exempel någon form av konvexitet, kan lösas effektivt. Tyvärr kan inte alla kvantitativa samband modelleras på ett konvext vis. Icke-konvexa problem kan angripas med heuristiska metoder, algoritmer som söker lösningar med hjälp av deterministiska eller stokastiska tumregler. Ibland fungerar det här väl, men heuristikerna kan sällan garantera kvaliteten på lösningen eller ens att en lösning påträffas. För vissa tillämpningar är det här oacceptabelt. Istället kan man tillämpa så kallad global optimering. Genom att successivt dela variabeldomänen i mindre delar och beräkna starkare gränser på det optimala värdet hittas en lösning inom feltoleransen. Den här metoden kallas branch-and-bound, ungefär dela-och-begränsa. För att ge undre gränser (vid minimering) approximeras problemet med enklare problem, till exempel konvexa, som kan lösas effektivt. I avhandlingen studeras tillvägagångssätt för att approximera differentierbara funktioner med konvexa underskattningar, speciellt den så kallade alphaBB-metoden. Denna metod adderar störningar av en viss form och garanterar konvexitet genom att sätta villkor på den perturberade Hessematrisen. Min forskning har lyft fram en naturlig utvidgning av de perturbationer som används i alphaBB. Nya metoder för att bestämma underskattningsparametrar har beskrivits och jämförts. I sammanfattningsdelen diskuteras global optimering ur bredare perspektiv på optimering och beräkningsalgoritmer.
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Resultaten påvisade små, men mätbara försämringar i minnes- och verbal förmåga hos personer som haft Parkinsons sjukdom under tre år. Jämfört med en kontrollgrupp uppvisade Parkinsonpatienter avvikande responser i hjärnans elektriska aktivitet under en korttidsminnesuppgift, och de presterade även sämre i olika typer av andra minnesuppgifter. Försämring i en specifik typ av minnesuppgift korrelerade med förminskad volym i höger hjärnhalva. Samband hittades också mellan sämre verbal förmåga och förminskad volym i djupa hjärnstrukturer. Förminskad hjärnvolym har tidigare påvisats hos dementa patienter i senare sjukdomsstadier. Forskningsresultaten bidrar med ny kunskap om kognitiva symptom och deras neurala bakgrund vid Parkinsons sjukdom. De tyder också på att tidig kognitiv funktionsnedsättning kan identifieras, vilket kan bidra till utvecklingen av sjukdomens behandling. Parkinsons sjukdom är den näst vanligaste neurogeriatriska sjukdomen efter Alzheimers sjukdom. Symptomen uppstår som följd av förminskad produktion av hjärnans transmittorämne dopamin. Parkinsons sjukdom har traditionellt betraktats som en progressiv motorisk sjukdom. Ny forskning tyder på att multipla hjärnsystem skadas, vilket resulterar i att även tankeprocesser påverkas. 75-80% uppskattas insjukna i demens 10-15 år efter diagnos, men det kognitiva sjukdomsförloppet och orsaken till demenssymptomen är tillsvidare okänd. I Finland uppskattas ca 10-12 000 personer ha Parkinsons sjukdom, varav ca 3 000 uppskattas ha demens. ----------------------------------------------------------------------------------------------------------------------------------------------------- Tutkimuksessa todettiin lieviä muutoksia muisti- ja kielellisissä toiminnoissa alle kolme vuotta sairastaneilla Parkinson-potilailla. Potilailla havaittiin poikkeavia aivosähkötoiminnan vasteita lyhytkestoista muistia mittaavan tehtävän aikana. Potilaat suoriutuivat myös verrokkiryhmää heikommin useissa muistitehtävissä. Heikentynyt tahaton muisti liittyi pienempään aivokuoren harmaan aineen paikalliseen tilavuuteen. Heikompi kielellinen suoriutuminen liittyi pienempään harmaan aineen tilavuuteen aivojen syvissä rakenteissa. Pienentyneitä aivorakenteiden tilavuuksia on aiemmin todettu dementoituneilla Parkinson-potilailla sairauden myöhemmissä vaiheissa. Tutkimustulokset tuovat uutta tietoa Parkinsonin taudin kognitiivisista oireista ja niiden aivoperäisestä taustasta. Tulosten perusteella on mahdollista tunnistaa jo varhaisia kognitiivisia muutoksia, mikä voi mahdollistaa tehokkaamman hoidon kohdentamisen. Parkinsonin tauti on Alzheimerin taudin jälkeen toiseksi yleisin neurogeriatrinen sairaus. Oirekuva liittyy aivojen dopaminergisen järjestelmän rappeutumiseen. Perinteisesti liikehäiriösairaudeksi luokiteltu sairaus vaurioittaa lukuisia muita aivojärjestelmiä aiheuttaen muutoksia myös mm. ajattelutoiminnoissa. Pitkään sairastaneista 75–80 prosentilla esiintyy dementiaoireita, mutta oireiden syy ja kehityskaari tunnetaan toistaiseksi huonosti. Suomessa on arviolta 10–12 000 Parkinson-potilasta, joista noin 3 000 arvioidaan kärsivän dementiaoireista.
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Bestraffning av internationella brott vid internationella och hybrida straffrättsliga domstolar har traditionellt och huvudsakligen grundat sig på principen om retributiv (vedergällande) rättvisa och ackusatorisk process snarare än återuppbyggande rättvisa och en inkvisitorisk modell. Därav har brottsoffrens ställning vid dessa straffrättsliga domstolar begränsat sig till den som innehas av vittnen vid Tribunalen som behandlar brott som begåtts i det forna Jugoslavien (ICTY), Internationella krigsförbrytartribunalen för Rwanda (ICTR) och Specialdomstolen för Sierra Leone (SCSL). Internationella brottmålsdomstolen (ICC), å sin sida, har medfört en viktig förändring gällande brottsoffrens ställning i internationella straffrättsliga fora, vilket innebär att de från att ha betraktats endast i egenskap av vittnen nu även har en rätt att delta och lämna sina synpunkter (i egenskap av brottsofferdeltagare) samt kräva gottgörelse. Denna trend har fortsatt inom området för internationell straffrätt, vilket manifesterats vid hybridtribunaler som tillsatts efter ICC såsom Kambodjadomstolen (ECCC) vid vilken brottsoffer kan agera civilrättsliga parter och Specialdomstolen för Libanon (STL) där brottsoffer kan inneha en deltagande roll. Den föreliggande studien behandlar två huvudsakliga frågeställningar, av vilka den första lyder: Vilken ställning tillskrivs brottsoffren vid internationella domstolar och hybridtribunaler? I detta hänseende argumenterar författaren, sammanfattningsvis, för att brottsoffrens ställning vid internationella straffrättsliga domstolar och hybridtribunaler huvudsakligen tar sig uttryck på tre sätt, d.v.s. som brottsoffer i egenskap av vittnen, som brottsoffer i egenskap av deltagande brottsoffer/civilrättsliga parter samt som brottsoffer som kräver gottgörelse. Den andra frågeställningen för denna studie lyder: På vilket sätt fungerar brottsoffrens ställning som vittnen, brottsofferdeltagande/civilrättsliga parter och gottgörelsekrävande vid internationella och hybrida straffrättsliga domstolar? -------------------------------------------------------------------------------------------------------------------------------------------------- Kansainvälisten rikosten rankaiseminen kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa on perinteisesti enimmäkseen perustunut retributiivisen oikeuden ja akkusatorisen menetelmän soveltamiseen pikemmin kuin restoratiivisen oikeuden ja inkvisitorisen menetelmän soveltamiseen. Niinpä uhrien asema kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa on rajoittunut todistajan asemaan entisen Jugoslavian kansainvälisessä sotarikostuomioistuimessa (ICTY), Ruandan kansainvälisessä sotarikostuomioistuimessa (ICTR) ja Sierra Leonen erikoistuomioistuimessa (SCSL). Kansainvälisen rikostuomioistuimen (ICC) perustaminen on kuitenkin merkinnyt tärkeää muutosta uhrien asemaan kansainvälisen rikosoikeuden alalla siten, että kun uhrit aiemmin nähtiin vain todistajina, heillä on nyt myös mahdollisuus tuoda esiin omat näkökantansa (osallistumisoikeus) ja vaatia hyvitystä. Tämä suuntaus on jatkunut kansainvälisen rikosoikeuden alalla ICC:n jälkeen perustetuissa hybridituomioistuimissa, kuten Kambodzhan erityistuomioistuimessa (ECCC), missä uhrit voivat olla asianosaisen asemassa, sekä Libanonin erityistuomioistuimessa (STL), missä uhrit voivat osallistua prosessiin. Tämä tutkimus käsittelee kahta keskeistä kysymystä. Ensinnäkin: Mikä on rikoksen uhrien asema kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa? Tutkimuksessa päädytään mm. siihen, että uhrien asema kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa voi koostua pääosin kolmesta ulottuvuudesta eli uhrit todistajina, uhrit prosessiin osallistujina/asianosaisina ja uhrit hyvityksen hakijoina. Tutkimuksen toinen keskeinen kysymys on: Miten uhrien asema todistajina, prosessiin osallistujina/ asianosaisina ja hyvityksen hakijoina toimii kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa?
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Den evolutionära förklaringen till den allmänt utbredda incestaversionen, dvs. motviljan för sex med nära släktingar, försöker besvara såväl frågan om varför incestaversionen gynnats i det naturliga urvalet som frågan om hur denna aversion regleras på individuell nivå. Eftersom inavlade barn har en försämrad biologisk duglighet än andra barn, medför kostnaderna av denna icke-optimala reproduktion ett selektionstryck mot inavel. I en serie studier visade vi att eftersom kvinnor i allmänhet satsar mer biologiska resurser på sina barn än vad män gör, känner kvinnor starkare incestaversion än män och eftersom det endast är fertila kvinnor som riskerar satsa resurser i en inavlad avkomma har även fertila kvinnor högre incestaversion än icke-fertila kvinnor. Vi visade också att de biologiska kostnaderna av inavel inte begränsas till enbart de individer som har incest. Eftersom alla våra biologiska släktingar sannolikt delar våra alleler speglar incestaversionen även de biologiska kostnader som incest mellan våra släktingar medför åt oss. Den psykologiska mekanism med vilken incestsituationer bedöms har hittills varit okänd. I våra studier testades teorin om självreflekterande empati. Enligt den teorin bedöms sådana situationer emotionellt genom att man själv föreställer sig ha sex med motsvarande släkting och känslan som väcks i denna process ger därefter emotionell information till bedömningen av andras incest. I tre delstudier fann vi att självreflektion var positivt associerat med styrkan av aversion gentemot andras incest, vilket stöder teorin om självreflekterande empati.
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The main objective of this doctoral dissertation is to reach a holistic and indepth understanding of the intercultural interaction within dyadic business relationships through the perspective of individual managers. The empirical setting is dyadic business relationships between Russian and Finnish firms in construction and engineering industries. The motivation for the study mainly arose from: 1) the lack of business marketing literature considering cultural and individual perspectives; 2) the need to find ways to study intercultural issues in business relationships, other than through the application of models derived from the work of Hofstede (1980). The study consists of two parts, an introductory essay containing the research objectives, theoretical foundations, methodological choices, limitations and contributions, and original research articles. The four articles each address a sub-objective: 1) to develop an understanding of intercultural business relationships development, cultural adaptation, and its role in the development of trust (Article 1); 2) to develop an appropriate methodological framework for studying business interaction from a cultural and individual perspective (Article 2); 3) to develop an understanding of the role of culture in individual manager’s sensemaking of interaction events in business relationships (Article 3); and 4) to develop an appropriate theoretical framework for studying interactive intercultural business relationships in international industrial markets (Article 4). The ontological and epistemological foundations are built on the interpretivist/ social constructivist view of reality. Interaction, in this study, is seen as being conducted between individuals, who are the key representative actors of their firms. In turn, culture is regarded both as an independent context existing prior to the individuals’ participation in it, and as knowledge incorporated by the individuals, who use it in sensemaking and interaction across cultures. The methods applied in the articles are: an interpretive qualitative study (Article 1), a literature review and conceptual analysis (Article 2), a structural analysis of the narratives and a metaphor analysis (Article 3), and a literature review and conceptual analysis (Article 4). The main contributions are the following. First, it contributes to business marketing literature by developing the theoretical, conceptual, and methodological underpinning of IMP theories in relation to culture. Second, the thesis contributes to the growing literature on managerial sensemaking in industrial markets by looking at it from a cultural perspective, as well as emphasizing the importance of figurative language in cultural sensemaking.
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The tourism industry is growing rapidly, and thus there is an urgent need to developing sustainable tourism. The research objective of the thesis is to explore and discuss the concept of sustainability within the tourism industry from a marketing point of view, focusing on the perspective of tourist producers’. The thesis consists of four studies, each of which contains different perspectives to support this overall objective. The first study deals with how a hotel can achieve economic sustainability by creating a high level of customer service delivery using a refined GAP-model. The second study examines how tourist producers at mass tourism destinations work with sustainable tourism as a strategic marketing tool in their tourism product development. The third study addresses economic sustainability at the macro level by estimating the tourism demand for Sweden and Norway in five different countries. In the fourth study, the concept of sustainable mass tourism is developed and analyzed from a conceptual standpoint. Study 1 and study 3 concentrate on economic sustainability from a micro and national perspective. The main contribution of Study 1 is the refined GAP-model, which can be seen as a theoretical contribution to the service marketing research. Study 3 shows that exchange rate trends strongly affect tourists’ choice of destination. Study 2 examines sustainable mass tourism as a strategic marketing tool at the destination level. The conclusions of Study 2 contribute to the findings of Study 4 and consider the tourist producers approach to sustainable tourism. One of the contributions of Study 4 is that the concept of sustainable tourism should be divided into three separate parts; economic sustainability, social sustainability and environmental sustainability.
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My dissertation is an interdisciplinary study of the relationship between the Swiss peasants and nobles in Friedrich Schiller’s play Wilhelm Tell (1804). Changes to this relationship are of particular interest. Communication in the play is examined via a micro-analysis based on Penelope Brown’s and Stephen C. Levinson’s theoretical framework Politeness: Some universals in language usage. (1978, 1987). Brown and Levinson distinguish between positivepoliteness and negative-politeness strategies and their distinction is useful for my argument, since they claim that the use of positive-politeness strategies reflects the speaker’s intention to minimize the distance between the interlocutors (Brown and Levinson 1987: 103). Negative-politeness strategies, by contrast, result in social distancing (Brown and Levinson 1987: 130). In accordance with Brown’s and Levinson’s theory, it can be argued that the distribution of positive-politeness and negative-politeness strategies reflects changes in the distance between the fictional interlocutors as representatives of their social classes in Wilhelm Tell. The analysis of the communication in the play highlights that existing conflicts within the social groups are resolved and replaced with solidarity (cf. ‘Claim ’common ground’ and ‘Claim in-group membership with H’) before the peasants and noblemen appear on stage simultaneously in III, 3. In the scene in question, Geßler forces Tell to shoot the apple off his son’s head. Although both nobles and peasants are present, they do not communicate with each other. Thus, communication between the social classes occurs for the first time in IV, 2. This scene is crucial with regard to the changes in the relationship between the social classes in the play. The younger generation, with Rudenz as a representative of the nobility and Melchthal as a representative of the peasants, break with the prevailing conventions and initiate a new type of cooperation based on mutual helping and equality in the right and the duty to protect the country from the violent oppressors representing Habsburg (cf. ‘Convey that S and H are cooperators’, ‘Claim reflexivity’ and ‘Claim reciprocity’). The linguistic analysis reveals the crucial role of the Swiss nobility in the development of the social utopia, as well as the non-contribution of Wilhelm Tell. In fact, Tell never communicates with the Swiss noblemen. The role of the nobility and the role of Wilhelm Tell are further investigated in a comparison between Schiller’s Wilhelm Tell and four of Schiller’s historical sources. These sources, which contain earlier, non-dramatic versions of the establishment of the Swiss Confederation, are the following: Kronica von der loblichen Eydtgnoschaft compiled by Petermann Etterlin (1507), Gemeiner loblicher Eydgnoschafft Stetten Landen vnd Völckeren Chronik wirdiger thaaten beschreybung (1548) written by Johann Stumpf, Chronicon Helveticum of Aegidius Tschudi (the publication of Iselin from 1734 and 1736) and Johannes von Müller’s Geschichten schweizerischer Eidgenossenschaft (1786). Thecomparison sheds light on the fact that both Tschudi and von Müller emphasize unity among the Swiss and cooperation in their attempt to defeat the enemy. However, Schiller has reinforced the role of the nobility in the cooperation. In addition, the comparison between Schiller’s play and the historical sources reveals profound differences with regard to the role of Wilhelm Tell. In all of Schiller’s sources, Tell is present at Rütli, whereas he is absent from Rütli in Schiller’s play. In the play in general, Tell is conspicuously separated from the other peasants. Explanations of my linguistic results, which correspond to the above mentioned differences between the roles of the figures in Wilhelm Tell and the depictions in Schiller’s sources, are found by comparing the path of Schiller’s Swiss towards an egalitarian perspective with the kind of social evolution depicted by the German philosopher Johann Benjamin Erhard in his essay Über das Recht des Volks zu einer Revolution (1795). Aiming at considering Schiller’s social utopia within the larger cultural framework of the German response to the French Revolution, the comparison suggests that both authors depict the need for social change in terms of a change in social hierarchies (Erhard 1970: 95-96, cf. Foi 2005: 225). Erhard’s essay thus helps explain the political intention of Schiller’s play to keep the ideals of the French Revolution as crucial aims but profoundly change the means towards freedom and equality. In his attempt to claim the political resistance of the nobles and peasants as just, however, Schiller sacrificed the figure of Wilhelm Tell. Guilty of the murder of Geßler, Tell was no longer suitable for the righteous revolution imagined by Schiller (cf. Bloch 2008: 215 and Schulz 2005: 228). This explains Tell’s absence in the Rütli scene, his isolation in the plot, as well as his non-contribution to the social utopia. Together, the linguistic analysis and contextualisation of Schiller’s play support my hypothesis that Wilhelm Tell describes a process of change in the relationship between peasants and nobles. The interdisciplinary approach to the topic proved to be fruitful for all areas of the research involved.
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Inorganic-organic sol-gel hybrid coatings can be used for improving and modifying properties of wood-based materials. By selecting a proper precursor, wood can be made water repellent, decay-, moisture- or UV-resistant. However, to control the barrier properties of sol-gel coatings on wood substrates against moisture uptake and weathering, an understanding of the surface morphology and chemistry of the deposited sol-gel coatings on wood substrates is needed. Mechanical pulp is used in production of wood-containing printing papers. The physical and chemical fiber surface characteristics, as created in the chosen mechanical pulp manufacturing process, play a key role in controlling the properties of the end-use product. A detailed understanding of how process parameters influence fiber surfaces can help improving cost-effectiveness of pulp and paper production. The current work focuses on physico-chemical characterization of modified wood-based materials with surface sensitive analytical tools. The overall objectives were, through advanced microscopy and chemical analysis techniques, (i) to collect versatile information about the surface structures of Norway spruce thermomechanical pulp fiber walls and understand how they are influenced by the selected chemical treatments, and (ii) to clarify the effect of various sol-gel coatings on surface structural and chemical properties of wood-based substrates. A special emphasis was on understanding the effect of sol-gel coatings on the water repellency of modified wood and paper surfaces. In the first part of the work, effects of chemical treatment on micro- and nano-scale surface structure of 1st stage TMP latewood fibers from Norway spruce were investigated. The chemicals applied were buffered sodium oxalate and hydrochloric acid. The outer and the inner fiber wall layers of the untreated and chemically treated fibers were separately analyzed by light microscopy, atomic force microscopy and field-emission scanning electron microscopy. The selected characterization methods enabled the demonstration of the effect of different treatments on the fiber surface structure, both visually and quantitatively. The outer fiber wall areas appeared as intact bands surrounding the fiber and they were clearly rougher than areas of exposed inner fiber wall. The roughness of the outer fiber wall areas increased most in the sodium oxalate treatment. The results indicated formation of more surface pores on the exposed inner fiber wall areas than on the corresponding outer fiber wall areas as a result of the chemical treatments. The hydrochloric acid treatment seemed to increase the surface porosity of the inner wall areas. In the second part of the work, three silane-based sol-gel hybrid coatings were selected in order to improve moisture resistance of wood and paper substrates. The coatings differed from each other in terms of having different alkyl (CH3–, CH3-(CH2)7–) and fluorocarbon (CF3–) chains attached to the trialkoxysilane sol-gel precursor. The sol-gel coatings were deposited by a wet coating method, i.e. spraying or spreading by brush. The effect of solgel coatings on surface structural and chemical properties of wood-based substrates was studied by using advanced surface analyzing tools: atomic force microscopy, X-ray photoelectron spectroscopy and time-of-flight secondary ion spectroscopy. The results show that the applied sol-gel coatings, deposited as thin films or particulate coatings, have different effects on surface characteristics of wood and wood-based materials. The coating which has a long hydrocarbon chain (CH3-(CH2)7–) attached to the silane backbone (octyltriethoxysilane) produced the highest hydrophobicity for wood and wood-based materials.
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The main topic of the thesis is optimal stopping. This is treated in two research articles. In the first article we introduce a new approach to optimal stopping of general strong Markov processes. The approach is based on the representation of excessive functions as expected suprema. We present a variety of examples, in particular, the Novikov-Shiryaev problem for Lévy processes. In the second article on optimal stopping we focus on differentiability of excessive functions of diffusions and apply these results to study the validity of the principle of smooth fit. As an example we discuss optimal stopping of sticky Brownian motion. The third research article offers a survey like discussion on Appell polynomials. The crucial role of Appell polynomials in optimal stopping of Lévy processes was noticed by Novikov and Shiryaev. They described the optimal rule in a large class of problems via these polynomials. We exploit the probabilistic approach to Appell polynomials and show that many classical results are obtained with ease in this framework. In the fourth article we derive a new relationship between the generalized Bernoulli polynomials and the generalized Euler polynomials.