56 resultados para Conservation Strategies

em Helda - Digital Repository of University of Helsinki


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The area of intensively managed forests, in which required conditions for several liverwort species are seldom found, has expanded over the forest landscape during the last century. Liverworts are very sensitive to habitat changes, because they demand continuously moist microclimate. Consequently, about third of the forest liverworts have been classified as threatened or near threatened in Finland. The general objective of this thesis is to increase knowledge of the reproductive and dispersal strategies of the substrate-specific forest bryophytes. A further aim was to develop recommendations for conservation measures for species inhabiting unstable and stable habitats in forest landscape. Both population ecological and genetic methods have been applied in the research. Anastrophyllum hellerianum inhabits spatially and temporally limited substrate patches, decaying logs, which can be considered as unstable habitats. The results show that asexual reproduction by gemmae is the dominant mode of reproduction, whereas sexual reproduction is considerably infrequent. Unlike previously assumed, not only spores but also the asexual propagules may contribute to long-distance dispersal. The combination of occasional spore production and practically continuous, massive gemma production facilitates dispersal both on a local scale and over long distances, and it compensates for the great propagule losses that take place preceding successful establishment at suitable sites. However, establishment probability of spores may be restricted because of environmental and biological limitations linked to the low success of sexual reproduction. Long-lasting dry seasons are likely to result in a low success of sexual reproduction and decreased release rate of gemmae from the shoots, and consequent fluctuations in population sizes. In the long term, the substratum limitation is likely to restrict population sizes and cause local extinctions, especially in small-sized remnant populations. Contrastingly, larger forest fragments with more natural disturbance dynamics, to which the species is adapted, are pivotal to species survival. Trichocolea tomentella occupies stable spring and mesic habitats in woodland. The relatively small populations are increasingly fragmented with a high risk for extinction for extrinsic reasons. The results show that T. tomentella mainly invests in population persistence by effective clonal growth via forming independent ramets and in competitive ability, and considerably less in sexuality and dispersal potential. The populations possess relatively high levels of genetic diversity regardless of population size and of degree of isolation. Thus, the small-sized populations inhabiting stable habitats should not be neglected when establishing conservation strategies for the species and when considering the habitat protection of small spring sites. Restricted dispersal capacity, also on a relatively small spatial scale, is likely to prevent successful (re-)colonization in the potential habitat patches of recovering forest landscapes. By contrast, random short-range dispersal of detached vegetative fragments within populations at suitable habitat seems to be frequent. Thus, the restoration actions of spring and streamside habitats close to the populations of T. tomentella may contribute to population expansion. That, in turn, decreases the harmful effects of environmental stochasticity.

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Elucidating the mechanisms responsible for the patterns of species abundance, diversity, and distribution within and across ecological systems is a fundamental research focus in ecology. Species abundance patterns are shaped in a convoluted way by interplays between inter-/intra-specific interactions, environmental forcing, demographic stochasticity, and dispersal. Comprehensive models and suitable inferential and computational tools for teasing out these different factors are quite limited, even though such tools are critically needed to guide the implementation of management and conservation strategies, the efficacy of which rests on a realistic evaluation of the underlying mechanisms. This is even more so in the prevailing context of concerns over climate change progress and its potential impacts on ecosystems. This thesis utilized the flexible hierarchical Bayesian modelling framework in combination with the computer intensive methods known as Markov chain Monte Carlo, to develop methodologies for identifying and evaluating the factors that control the structure and dynamics of ecological communities. These methodologies were used to analyze data from a range of taxa: macro-moths (Lepidoptera), fish, crustaceans, birds, and rodents. Environmental stochasticity emerged as the most important driver of community dynamics, followed by density dependent regulation; the influence of inter-specific interactions on community-level variances was broadly minor. This thesis contributes to the understanding of the mechanisms underlying the structure and dynamics of ecological communities, by showing directly that environmental fluctuations rather than inter-specific competition dominate the dynamics of several systems. This finding emphasizes the need to better understand how species are affected by the environment and acknowledge species differences in their responses to environmental heterogeneity, if we are to effectively model and predict their dynamics (e.g. for management and conservation purposes). The thesis also proposes a model-based approach to integrating the niche and neutral perspectives on community structure and dynamics, making it possible for the relative importance of each category of factors to be evaluated in light of field data.

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Mutation and recombination are the fundamental processes leading to genetic variation in natural populations. This variation forms the raw material for evolution through natural selection and drift. Therefore, studying mutation rates may reveal information about evolutionary histories as well as phylogenetic interrelationships of organisms. In this thesis two molecular tools, DNA barcoding and the molecular clock were examined. In the first part, the efficiency of mutations to delineate closely related species was tested and the implications for conservation practices were assessed. The second part investigated the proposition that a constant mutation rate exists within invertebrates, in form of a metabolic-rate dependent molecular clock, which can be applied to accurately date speciation events. DNA barcoding aspires to be an efficient technique to not only distinguish between species but also reveal population-level variation solely relying on mutations found on a short stretch of a single gene. In this thesis barcoding was applied to discriminate between Hylochares populations from Russian Karelia and new Hylochares findings from the greater Helsinki region in Finland. Although barcoding failed to delineate the two reproductively isolated groups, their distinct morphological features and differing life-history traits led to their classification as two closely related, although separate species. The lack of genetic differentiation appears to be due to a recent divergence event not yet reflected in the beetles molecular make-up. Thus, the Russian Hylochares was described as a new species. The Finnish species, previously considered as locally extinct, was recognized as endangered. Even if, due to their identical genetic make-up, the populations had been regarded as conspecific, conservation strategies based on prior knowledge from Russia would not have guaranteed the survival of the Finnish beetle. Therefore, new conservation actions based on detailed studies of the biology and life-history of the Finnish Hylochares were conducted to protect this endemic rarity in Finland. The idea behind the strict molecular clock is that mutation rates are constant over evolutionary time and may thus be used to infer species divergence dates. However, one of the most recent theories argues that a strict clock does not tick per unit of time but that it has a constant substitution rate per unit of mass-specific metabolic energy. Therefore, according to this hypothesis, molecular clocks have to be recalibrated taking body size and temperature into account. This thesis tested the temperature effect on mutation rates in equally sized invertebrates. For the first dataset (family Eucnemidae, Coleoptera) the phylogenetic interrelationships and evolutionary history of the genus Arrhipis had to be inferred before the influence of temperature on substitution rates could be studied. Further, a second, larger invertebrate dataset (family Syrphidae, Diptera) was employed. Several methodological approaches, a number of genes and multiple molecular clock models revealed that there was no consistent relationship between temperature and mutation rate for the taxa under study. Thus, the body size effect, observed in vertebrates but controversial for invertebrates, rather than temperature may be the underlying driving force behind the metabolic-rate dependent molecular clock. Therefore, the metabolic-rate dependent molecular clock does not hold for the here studied invertebrate groups. This thesis emphasizes that molecular techniques relying on mutation rates have to be applied with caution. Whereas they may work satisfactorily under certain conditions for specific taxa, they may fail for others. The molecular clock as well as DNA barcoding should incorporate all the information and data available to obtain comprehensive estimations of the existing biodiversity and its evolutionary history.

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This Ph.D. thesis Participation or Further Exclusion? Contestations over Forest Conservation and Control in the East Usambara Mountains, Tanzania describes and analyses the shift in the prevailing discourse of forest and biodiversity conservation policies and strategies towards more participatory approaches in Tanzania, and the changes in the practises of resource control. I explore the scope for and limits to the different actors and groups who are considered to form the community, to participate in resource control, in a specific historical and socio-economic context. I analyse whether, how and to which extent the targets of such participatory conservation interventions have been able to affect the formal rules and practices of resource control, and explore their different responses and discursive and other strategies in relation to conservation efforts. I approach the problematic through exploring certain participatory conservation interventions and related negotiations between the local farmers, government officials and the external actors in the case of two protected forest reserves in the southern part of the East Usambaras, Tanzania. The study area belongs to the Eastern Arc Mountains that are valued globally and nationally for their high level of biodiversity and number of endemic and near endemic species. The theoretical approach draws from theorising on power, participation and conservation in anthropology of development and post-structuralist political ecology. The material was collected in three stages between 2003 and 2008 by using an ethnographic approach. I interviewed and observed the actors and their resource use and control practices at the local level, including the representatives of the villagers living close to the protected forests and the conservation agency, but also followed the selected processes and engaged with the non-local agencies involved in the conservation efforts in the East Usambaras. In addition, the more recent processes of change and the actors strategies in resource control were contextualised against the social and environmental history of the study area and the evolvement of institutions of natural resource control. My findings indicate that the discourse of participation that has emerged in global conservation policy debate within the past three decades, and is being institutionalised in the national policies in many countries, including Tanzania, has shaped the practices of forest conservation in the East Usambaras, although in a fragmented and uneven way. Instrumental interpretation of participation, in which it is to serve the goals of improving the control of the forest and making it more acceptable and efficient, has prevailed among the governmental actors and conservation organisations. Yet, there is variation between the different projects and actors promoting participatory conservation regarding the goals and means of participation, e.g. to which extent the local people are to be involved in decision-making. The actors representing communities also have their diverse agendas, understandings and experiences regarding the rationality, outcomes and benefits of being involved in forest control, making the practices of control fluid. The elements of the exclusive conservation thinking and practices co-exist with the more recent participatory processes, and continue to shape the understandings and strategies of the actors involved in resource control. The ideas and narratives of the different discourses are reproduced and selectively used by the parties involved. The idea of forest conservation is not resisted as such by most of the actors at local level, quite the opposite. However, the strict regulations and rules governing access to resources, such as valuable timber species, continue to be disputed by many. Furthermore, the history of control, such as past injustices related to conservation and unfulfilled promises, undermines the participation of certain social groups in resource control and benefit sharing. This also creates controversies in the practices of conservation, and fuels conflicts regarding the establishment of new protected areas. In spite of this, the fact that the representatives of the communities have been invited to the arenas where information is shared, and principles and conditions of forest control and benefit sharing are discussed and partly decided upon, has created expectations among the participants, and opened up opportunities for some of the local actors to enhance their own, and sometimes wider interests in relation to resource control and the related benefits. The local actors experiences of the previous government and other interventions strongly affect how they position themselves in relation to conservation interventions, and their responses and strategies. However, my findings also suggest, in a similar way to research conducted in some other protected areas, that the benefits of participation in conservation and resource control tend to accrue unevenly between different groups of local people, e.g. due to unequal access to information and differences in their initial resources and social position.

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One major reason for the global decline of biodiversity is habitat loss and fragmentation. Conservation areas can be designed to reduce biodiversity loss, but as resources are limited, conservation efforts need to be prioritized in order to achieve best possible outcomes. The field of systematic conservation planning developed as a response to opportunistic approaches to conservation that often resulted in biased representation of biological diversity. The last two decades have seen the development of increasingly sophisticated methods that account for information about biodiversity conservation goals (benefits), economical considerations (costs) and socio-political constraints. In this thesis I focus on two general topics related to systematic conservation planning. First, I address two aspects of the question about how biodiversity features should be valued. (i) I investigate the extremely important but often neglected issue of differential prioritization of species for conservation. Species prioritization can be based on various criteria, and is always goal-dependent, but can also be implemented in a scientifically more rigorous way than what is the usual practice. (ii) I introduce a novel framework for conservation prioritization, which is based on continuous benefit functions that convert increasing levels of biodiversity feature representation to increasing conservation value using the principle that more is better. Traditional target-based systematic conservation planning is a special case of this approach, in which a step function is used for the benefit function. We have further expanded the benefit function framework for area prioritization to address issues such as protected area size and habitat vulnerability. In the second part of the thesis I address the application of community level modelling strategies to conservation prioritization. One of the most serious issues in systematic conservation planning currently is not the deficiency of methodology for selection and design, but simply the lack of data. Community level modelling offers a surrogate strategy that makes conservation planning more feasible in data poor regions. We have reviewed the available community-level approaches to conservation planning. These range from simplistic classification techniques to sophisticated modelling and selection strategies. We have also developed a general and novel community level approach to conservation prioritization that significantly improves on methods that were available before. This thesis introduces further degrees of realism into conservation planning methodology. The benefit function -based conservation prioritization framework largely circumvents the problematic phase of target setting, and allowing for trade-offs between species representation provides a more flexible and hopefully more attractive approach to conservation practitioners. The community-level approach seems highly promising and should prove valuable for conservation planning especially in data poor regions. Future work should focus on integrating prioritization methods to deal with multiple aspects in combination influencing the prioritization process, and further testing and refining the community level strategies using real, large datasets.

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Tutkielman tavoitteena on tutkia, millaisia käännösstrategioita DVD-tekstittämisessä suositaan reaalioita eli kulttuurisidonnaisia käsitteitä käännettäessä. Lähtökohtana on, että osaa strategioista voidaan käyttää reaalioiden kulttuurisen erilaisuuden korostamiseen, osaa taas tämän erilaisuuden häivyttämiseen. Nämä kaksi kategoriaa eivät kuitenkaan kata kaikkia mahdollisia strategioita, minkä vuoksi myös neutraalit strategiat otetaan tutkielmassa huomioon. Tutkielman aineisto koostuu Suomessa nimillä Ruuvit löysällä ja Pikku-Britannia tunnettujen brittiläisten sketsisarjojen DVD-julkaisuista. Molemmat tutkituista julkaisuista käsittävät yhden tuotantokauden. Formaatiltaan sketsisarjat perustuvat lukuisiin lyhyisiin kohtauksiin, joissa käsitellään useita eri aihealueita. Tämän vuoksi ne soveltuvat erinomaisesti reaalioiden tutkimukseen. Tutkittava kääntämisen laji on DVD-kääntäminen, koska sen merkityksen voidaan katsoa kasvaneen DVD:n lisääntyneen suosion myötä. Tutkielman teoriatausta muodostuu reaalioiden, käännösstrategioiden ja tekstityksen teoriasta. Näistä osa-alueista ensimmäisessä korostuu kulttuurin vaikutus kieleen ja siten myös kääntämiseen, kun taas toinen pohjautuu sekä tekstitason kotouttavista ja vieraannuttavista käännösstrategioista että sanatason lokaaleista strategioista esitettyyn teoriaan, ja kolmannessa nousevat esille sanan ja kuvan yhteistyö sekä muut tekstittämiseen vaikuttavat tekijät, kuten rajallinen käytettävissä oleva tila ja aika. Yhdessä teorian eri osa-alueet mahdollistavat tutkimuksen, jossa voidaan tarkastella kulttuuristen, kielellisten ja audiovisuaalisten piirteiden vaikutusta reaalioiden kääntämiseen. Tutkielmassa käytetään kvalitatiivista ja kvantitatiivista tutkimusmenetelmää. Kvalitatiivinen menetelmä perustuu käännösstrategioiden käyttötapojen kuvaamiseen tutkimalla tutkimusaineistosta transkriboituja reaalioiden käännöksiä yksittäisissä tapauksissa. Analyysissa otetaan huomioon ensisijaisesti reaalioiden tekstuaalinen ja audiovisuaalinen konteksti sekä niiden oletettu tunnistettavuus käännösten kohdekulttuurissa. Tätä analyysia täydennetään kaikkien havaittujen reaalioiden kääntämistä kuvaavalla kvantitatiivisella menetelmällä. Tutkielman tulokset viittaavat siihen, että erilaisten käännösstrategioiden välillä on huomattavia eroja siinä, millä tavoin ja miten usein niitä käytetään. Lisäksi tulokset osoittavat odotetusti sen, että kotouttavat ja vieraannuttavat strategiat eivät sulje toisiaan pois, vaan niitä molempia voidaan käyttää saman käännöksen sisällä. Kokonaisuutena tutkielmassa tuodaan ilmi monia aihealueen tutkimiseen liittyviä haasteita aina kulttuurin määrittelystä audiovisuaalisen aineiston analysoimiseen asti. Avainsanat: Kulttuurisidonnaiset käsitteet, käännösstrategia, tekstittäminen, kotouttaminen, vieraannuttaminen

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Pro gradu –tutkielman aiheena on kulttuurin ominaispiirteiden kääntäminen. Teksteissä kulttuurin jälki voi näkyä monin eri tavoin. Tutkielman kohteena ovat erityisesti käännösstrategiat, joita kääntäjät käyttävät kohdatessaan kulttuurisidonnaisia viittauksia. Tutkielma nostaa esiin myös niitä tekijöitä, jotka vaikuttavat siihen, minkälaisia käännösstrategioita kääntäjät valitsevat. Näistä tekijöistä tutkielma keskittyy kääntämisen normeihin. Tutkielma pureutuu kulttuurisidonnaisten viitteiden kääntämiseen tarkastelemalla kahta suomalaista kaunokirjallista teosta ja niiden käännöksiä. Tutkielman aineistona ovat Matti Yrjänä Joensuun kaksi rikosromaania ja näiden käännökset. Teoksista toinen on vuonna 1983 suomeksi julkaistu Harjunpää ja poliisin poika, jonka englanninkielinen käännös Harjunpaa the stone murders julkaistiin vuonna 1986. Toinen teos on vuonna 2003 julkaistu Harjunpää ja pahan pappi ja sen käännös The Priest of Evil vuodelta 2006. Tutkielman tavoitteena on selvittää, minkälaisia kulttuurisidonnaisia viittauksia romaanit sisälsivät, minkälaisia käännösstrategioita kääntäjät käyttivät kääntäessään näitä viittauksia ja mikä voisi selittää heidän strategisia valintojaan. Tutkielma pyrkii vastaamaan kysymykseen siitä, voisiko jonkin kääntämistä koskevan normin olemassa olo selittää kääntäjien strategisia valintoja. Tutkielman tavoitteena on myös selvittää, suositaanko kääntämisessä englannin kieleen niin kutsuttuja kotouttavia käännösstrategioita ja ovatko käännösstrategiat ja kääntämistä koskevat normit muuttuneet kahdenkymmenen vuoden aikana. Näihin kysymyksiin vastaamiseksi suomenkielisistä teksteistä on etsitty kaikki kulttuurisidonnaisia viittauksia sisältävät tekstinkohdat. Näitä vastaavat kohdat on sitten etsitty käännöksistä ja suomen- ja englanninkielisiä kohtia on vertailtu keskenään. Molemmat suomenkieliset romaanit sisältävät runsaasti kulttuurisidonnaisia viittauksia. Suurimman kulttuurisidonnaisten viittausten ryhmän muodostivat molemissa romaaneissa henkilöiden nimet. Romaanin sisälsivät myös runsaasti viittauksia maantieteeseen, erityisesti kulttuurimaantieteeseen, ja yhteiskuntaan. Sitä vastoin viittaukset suomalaiseen kulttuuriin ja historiaan olivat vähäisempiä. Tutkielma osoittaa, että kääntäessään suomesta englannin kielelle suomalaisen rikoskirjallisuuden kääntäjät saattavat käyttää enemmän vieraannuttavia strategioita kuin kotouttavia strategioita ja että he suosivat vieraannuttavia strategioita kasvavassa määrin. Harjunpään ja pahan papin kääntäjä käytti enemmän vieraannuttavia strategioita kuin Harjunpään ja poliisin pojan kääntäjä kaksikymmentä vuotta aikaisemmin. Tutkielman tulokset eivät tue väitettä siitä, että käännettäessä englannin kielelle suosittaisiin kotouttavia strategioita. Näyttää siltä, että vieraannuttavia strategioita on käytetty enemmän ja käytetään yhä enenevässä määrin. Lisääntyvän vieraannuttamisen taustalla voi olla useita syitä, kuten suomalaisen kulttuurin lisääntynyt tunnettuus maailmalla, rikosromaanin genren vaatimukset tai muutokset kääntäjäyhteisön arvoissa. Tutkielman tulosten perusteella näyttää siltä, että ainakin muutoksia normeissa ja arvoissa on tapahtunut. Lisätutkimuksen avulla voitaisiin selvittää, pätevätkö tutkielman tulokset muihin romaaneihin ja niiden käännöksiin tai muihin genreihin käännettäessä suomesta englantiin. Lisätutkimus voisi nojautua laajempaan ja erilaisia tekstejä kattavaan aineistoon. Jatkotutkimus voisi myös sisältää kääntäjien haastatteluita tai kyselyitä kääntäjille. Näiden avulla voitaisiin saada lisäselvyyttä syistä heidän strategisille valinnoilleen. Asiasanat: Käännöskirjallisuus – kaunokirjallisuus Kääntäminen – suomen kieli – englannin kieli Kääntäminen – strategia Kääntäminen - normi

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Suomen koulutuspolitiikasta vastaavat viranomaiset ovat reagoineet kansainvälisten kommunikaatiotarpeiden asettamiin haasteisiin ja muuttaneet yhden lukion A-tasoisen vieraan kielen kurssin sisällön vastaamaan suullisen viestinnän tarpeita. Tutkimuksessa selvitetään, miten englannin puhestrategioita voi opettaa suomalaisille lukiolaisille ja mitä metodeja on käytettävissä puhestrategioiden oppimisen arvioimiseksi. Vastaan asettamiini kysymyksiin aikaisemman tutkimuskirjallisuuden ja englannin kielen lukio-opetuksesta keräämäni aineiston avulla. Keskeisiä elementtejä tutkielmassa ovat erityisesti pragmaattinen kompetenssi ja kolme yleisen tason puhestrategiaa (keskustelun aloittaminen, oman puheenvuoron säilyttäminen sekä keskustelun ylläpitäminen). Aineistossa on mukana 65 ensimmäisen vuosiluokan lukiolaista (luokka A ja B) Helsingistä ja Espoosta. Opetusmateriaalina on käytetty SCOTS korpusta; tarkemmin määriteltynä puhetiedosto nimeltä Conversation 20: Four secondary school girls in the North East. Tiedostossa esille tulleet, kolmeen puhestrategiaan liittyvät fraasit, sanat ja rakenteet havainnollistettiin opiskelijoille mm. AntConc - konkordanssiohjelman avulla. Opiskelijat tekivät myös kirjallisia ja suullisia harjoituksia, jotka liittyivät puhestrategioihin. Neljälle vapaaehtoiselle opiskelijalle suunnattu toinen suullinen tehtävätyyppi vapaamuotoisine keskusteluineen äänitettiin, transkriboitiin ja tuloksia arvioitiin mm. eurooppalaisen viitekehyksen avulla. Lisäksi B - luokka vastasi kyselylomakkeeseen, jossa kysyttiin heidän mielipiteitään esim. hyödyllisimmästä testioppitunnista sekä heidän osallistumishalukkuudestaan uudelle pitkän englannin kahdeksannelle syventävälle kurssille. Tutkimustulokset ovat kannustavia ja osoittavat, että puhestrategioita on mahdollista opettaa jo lukiotasolla. Vaikka tutkimuksessa käytetty lähestymistapa oli opiskelijoille osittain uusi, valtaosa heistä myönsi oppineensa uutta englannin kielen keskustelurakenteista. Lisäksi vapaaehtoisten opiskelijoiden äänitetyt ja transkriboidut keskustelut tarjoavat hyvän lähtökohdan mahdolliselle jatkotutkimukselle.

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These longitudinal studies focused on investigating young adults during transition into a new educational environment. The aims were to examine: (1) what kinds of achievement and social strategies young adults deploy, (2) whether the deployment of these strategies predicts people's success in their studies, their life events, their peer relationships, and their well-being, (3) whether young adults' success in dealing with educational transition (e.g. success in studies, life events, peer relationships and well-being) predict changes in their strategies and well-being, and (4) the associations between young adults' social strategies, interpersonal behaviour, person perception, and their peer relationships and satisfaction with them. The participants were students from Helsinki university and from two vocational institutes (the numbers ranging between 92 and 303). The results revealed that achievement and social strategies contributed to individuals' success in dealing with both the academic and interpersonal challenges of a new environment. Social strategies were also associated with online interpersonal behaviour and person perception, which mediated their impact on peer relationships. Achievement and social strategies changed as a result of environmental feedback. However, they also showed high stability, forming reciprocal and cumulative associations with the feedback the individuals received about their success in dealing with educational transition: the use of functional strategies, such as optimistic, defensive-pessimistic and planning-oriented strategies, increased their success, which in turn enhanced their well-being and further deployment of functional strategies. The opposite was true in the case of dysfunctional strategies, such as self-handicapping and avoidance. Key words : Achievement strategies, social strategies, transition, young adults, life events, sociometric status, social behaviour, person perception, well-being.

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Celiac disease, or gluten intolerance, is triggered by dietary glutens in genetically susceptible individuals and it affects approximately 1% of the Caucasian population. The best known genetic risk factors for celiac disease are HLA DQ2 and DQ8 heterodimers, which are necessary for the development of the disease. However, they alone are not sufficient for disease induction, other risk factors are required. This thesis investigated genetic factors for celiac disease, concentrating on susceptibility loci on chromosomes 5q31-q33, 19p13 and 2q12 previously reported in genome-wide linkage and association studies. In addition, a novel genotyping method for the detection of HLA DQ2 and DQ8 coding haplotypes was validated. This study was conducted using Finnish and Hungarian family materials, and Finnish, Hungarian and Italian case-control materials. Genetic linkage and association were analysed in these materials using candidate gene and fine-mapping approaches. The results confirmed linkage to celiac disease on the chromosomal regions 5q31-q33 and 19p13. Fine-mapping on chromosome 5q31-q33 revealed several modest associations in the region, and highlighted the need for further investigations to locate the causal risk variants. The MYO9B gene on chromosome 19p13 showed evidence for linkage and association particularly with dermatitis herpetiformis, the skin manifestation of celiac disease. This implies a potential difference in the genetic background of the intestinal and skin forms of the disease, although studies on larger samplesets are required. The IL18RAP locus on chromosome 2q12, shown to be associated with celiac disease in a previous genome-wide association study and a subsequent follow-up, showed association in the Hungarian population in this study. The expression of IL18RAP was further investigated in small intestinal tissue and in peripheral blood mononuclear cells. The results showed that IL18RAP is expressed in the relevant tissues. Two putative isoforms of IL18RAP were detected by Western blot analysis, and the results suggested that the ratios and total levels of these isoforms may contribute to the aetiology of celiac disease. A novel genotyping method for celiac disease-associated HLA haplotypes was also validated in this thesis. The method utilises single-nucleotide polymorphisms tagging these HLA haplotypes with high sensitivity and specificity. Our results suggest that this method is transferable between populations, and it is suitable for large-scale analysis. In conclusion, this doctorate study provides an insight into the roles of the 5q31-q33, MYO9B, IL18RAP and HLA loci in the susceptibility to celiac disease in the Finnish, Hungarian and Italian populations, highlighting the need for further studies at these genetic loci and examination of the function of the candidate genes.

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Vascular intimal hyperplasia is a major complication following angioplasty. The hallmark feature of this disorder is accumulation of dedifferentiated smooth muscle cells (SMCs) to the luminal side of the injured artery, cellular proliferation, migration, and synthesis of extracellular matrix. This finally results in intimal hyperplasia, which is currently considered an untreatable condition. According to current knowledge, a major part of neointimal cells derive from circulating precursor cells. This has outdated the traditional in vitro cell culture methods of studying neointimal cell migration and proliferation using cultured medial SMCs. Somatostatin and some of its analogs with different selectivity for the five somatostatin receptors (sst1 through sst5) have been shown to have vasculoprotective properties in animal studies. However, clinical trials using analogs selective for sst2/sst3/sst5 to prevent restenosis after percutaneous transluminal coronary angioplasty (PTCA) have failed to show any major benefits. Sirolimus is a cell cycle inhibitor that has been suggested to act synergistically with the protein-tyrosine kinase inhibitor imatinib to inhibit intimal hyperplasia in rat already at well-tolerated submaximal oral doses. The mechanisms behind this synergy and its long-term efficacy are not known. The aim of this study was to set up an ex vivo vascular explant culture model to measure neointimal cell activity without excluding the participation of circulating progenitor cells. Furthermore, two novel potential vasculoprotective treatment strategies were evaluated in detail in rat models of intimal hyperplasia and in the ex vivo explant model: sst1/sst4-selective somatostatin receptor analogs and combination treatment with sirolimus and imatinib. This study shows how whole vessel explants can be used to study the kinetics of neointimal cells and their progenitors, and to evaluate the anti-migratory and anti-proliferative properties of potential vasculoprotective compounds. It also shows how the influx of neointimal progenitor cells occurs already during the first days after vascular injury, how the contribution of cell migration is more important in the injury response than cell proliferation, and how the adventitia actively contribute in vascular repair. The vasculoprotective effect of somatostatin is mediated preferentially through sst4, and through inhibition of cell migration rather than of proliferation, which may explain why sst2/sst3/sst5-selective analogs have failed in clinical trials. Furthermore, a brief early oral treatment with the combination of sirolimus and imatinib at submaximal doses results in long-term synergistic suppression of intimal hyperplasia. The synergy is a result of inhibition of post-operative thrombocytosis and leukocytosis, inhibition of neointimal cell migration to the injury-site, and maintenance of cell integrity by inhibition of apoptosis and SMC dedifferentiation. In conclusion, the influx of progenitor cells already during the first days after injury and the high neointimal cell migratory activity underlines the importance of early therapeutic intervention with anti-migratory compounds to prevent neointimal hyperplasia. Sst4-selective analogs and the combination therapy with sirolimus and imatinib represent potential targets for the development of such vasculoprotective therapies.

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Conservation and sustainable management of tropical forests needs a holistic approach: in addition to ecological concerns, socio-economic issues including cultural aspects must be taken into consideration. An ability to adapt practices is a key to successful collaborative natural resource management. Achieving this requires local participation and understanding of local conceptions of the environment. This study examined these issues in the context of northern Thailand. Northern uplands are the home of much of the remaining natural forest in Thailand and several ethnic minority groups commonly referred to as hill tribes. The overall purpose of this study was to grasp a regional view of an ethnically diverse forested area and to elicit prospects to develop community forestry for conservation purposes and for securing people s livelihood. Conservation was a central goal of management as the forests in the area were largely designated as protected. The aim was to study local perceptions, objectives, values and practices of forest management, under the umbrella of the concept environmental literacy, as well as the effects of forest policy on community management goals and activities. Environmental literacy refers to holistic understanding of the environment. It was used as a tool to examine people s views, interests, knowledge and motivation associated to forests. The material for this study was gathered in six villages in Chiang Mai Province. Three minority groups were included in the study, the Karen, Hmong and Lawa, and also the Thai. Household and focus group interviews were conducted in the villages. In addition, officials at district, regional and national levels, workers of non-governmental organisations, and academics were interviewed, and some data were gathered from the students of a local school. The results showed that motivation for protecting the forests existed among each ethnic group studied. This was a result of culture and traditions evolved in the forest environment but also of a need to adapt to a changed situation and environment and to outside pressures. The consequences of deforestation were widely agreed on in the villages, and the impact of socio-economic changes on the forests and livelihood was also recognised. The forest was regarded as a source of livelihood providing land, products and services essential to the people inhabiting rural uplands. Traditions, fire control, cooperation, reforestation, separation of protected and utilisable areas, and rules were viewed as central for conservation. For the villagers, however, conservation meant sustainable use, whereas the government has tended to prefer strict restrictions on forest resource use. Thus, conflicts had arisen. Between communities, cooperation was more dominant than conflict. The results indicated that the heterogeneity of forest dwellers, although it has to be recognised, should not be overemphasised: ethnic diversity can be considered as no major obstacle for successful community forestry. Collaborative management is particularly important in protected areas in order to meet the conservation goals while providing opportunities for livelihood. Forest management needs more positive incentives and increased dialogue.