472 resultados para yliopiston kolmas tehtävä


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Tämän tutkimuksen tarkoituksena on selvittää psykoottisen mielenterveyspotilaan uskonnonvapautta. Tutkimuskysymyksiä on kolme: Millä perusteilla psykoottisen potilaan uskonnonvapaus on turvattu ja millä perusteilla sitä rajoitetaan? Miten psykoottinen ja uskonnollinen todellisuudentulkinta eroavat toisistaan? Vaarantaako psykiatriseen todellisuudentulkintaan perustuva hoito potilaan negatiivisen uskonnonvapauden eli oikeuden elää ilman uskontoa? Tutkimusmetodina on systemaattinen analyysi. Lähteet ovat perustusoikeudet, mielenterveyslaki, potilaslaki, YK:n Principles for the protection of persons with mental illness and the improvement of mental health care, Maailman psykiatriyhdistyksen Madridin julistus ja Suomen mielenterveysseuran Mielenterveyspotilaan oikeudet. Uskonnonvapautta tarkastellaan tässä tutkimuksessa kahden eri vapauskäsityksen näkökulmasta: ulkoisena vapautena, joka edellyttää kompetenssia ja autenttisuutta, sekä ulkoisen ja sisäisen vapauden summana, johon kompetenssi ja autenttisuus sisältyvät. Psykoottisella potilaalla on ihmisyytensä ja kansalaisuutensa perusteella lähtökohtaisesti täysi uskonnonvapaus, mutta sitä voidaan rajoittaa. Jos uskonnonvapaus ymmärretään ulkoiseksi vapaudeksi, rajoittaa psykoottisen potilaan uskonnonvapautta tahdosta riippumattomassa hoidossa hänen terveytensä ja turvallisuutensa suojaaminen. Uskonnonvapauden rajoittaminen voidaan perustella sillä, ettei psykoottinen potilas täytä uskonnonvapauden edellytyksiä eli kompetenssia ja autenttisuutta, sillä, että potilaan terveyteen ja turvallisuuteen liittyvät oikeudet priorisoidaan uskonnonvapauden yläpuolelle sekä sillä, että pyritään terveyshyötyyn. Jos uskonnonvapaus ymmärretään ulkoisen ja sisäisen vapauden summaksi, on psykoosi uskonnonvapautta rajoittava tekijä, koska se tekee yksilöstä epäautenttisen ja puuttuu hänen kompetenssiinsa. Psykoosin (myös tahdosta riippumaton) hoito voidaan ymmärtää tällöin yritykseksi palauttaa uskonnonvapaus. Rajoittamalla ulkoista uskonnonvapautta pyritään maksimoimaan ulkoisen ja sisäisen uskonnonvapauden summa. Vaikka psykoottisella ja uskonnollisella todellisuudentulkinnalla on yhtäläisyyksiä, niiden toisistaan erottaminen on tärkeää, koska yksilöllä, jonka todellisuudentulkinta määritellään psykoottiseksi, on oikeus saada hoitoa, kun taas yksilön uskonnollista todellisuudentulkintaa suojaa uskonnonvapaus eikä sitä saa hoitaa sairautena. Lähteiden mukaan psykoottisen ja uskonnollisen todellisuudentulkinnan toisistaan erottaminen diagnostisten kriteerien ja lääketieteellisen tiedon avulla on lääkärin tehtävä. Tutkimuksessani esitän kaksi periaatetta, joiden avulla todellisuudentulkinnat voidaan erottaa toisistaan. Yksinäinen puu ei pala -periaatteen mukaan yksilön todellisuudentulkinta on uskonnollinen, mikäli se jaetaan jossain yhteisössä. Hedelmistään puu tunnetaan -periaatteen mukaan yksilön todellisuudentulkinta on uskonnollinen, mikäli sen terveydelliset ja sosiaaliset seuraukset ovat hyvät. Antipsykiatrinen kritiikki väittää psykiatrian olevan uskonto. Jos väite on tosi, puututaan tahdosta riippumattomassa hoidossa yksilön oikeuteen elää ilman uskontoa, sillä ko. hoidossa olevan psykoottisen potilaan on pakko suostua siihen, että häntä hoidetaan psykiatrian arvojen ja todellisuudentulkinnan mukaan. Vaikuttaa kuitenkin siltä, että jos psykiatria määritellään uskonnoksi, uskonnon käsite kärsii inflaation. Koska psykoottisen potilaan uskonnonvapaus on pohjimmiltaan eettinen kysymys, on tärkeää myöntää psykiatrian arvosidonnaisuus. Tällöin voidaan tehdä tietoisesti moraalisia päätöksiä ja kantaa moraalinen vastuu esimerkiksi diagnoosin määrittelyssä. Psykiatrian voidaan katsoa perustuvan universaaleihin arvoihin samalla tavalla kuin ihmisoikeuksienkin.

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The aim of this study was to look at the metaphors contemporary merchant seamen use for their ship and for their life at sea. The larger theoretical framework of the study consisted of worldview, which is one of the key concepts of comparative religion. The data for the study consisted of 91 interviews with Finnish professional seafarers that were conducted in 1996, 1999, and 2000, field journals that were written during two periods of fieldwork in 1996 and 1999-2000, and correspondence with some of the Finnish seafarers during 1999-2002. The data was analyzed by using metaphor theory. The study consists of two parts. The first part is ethnography of modern Finnish shipworld. This entails work, organization, hierarchy and gender. The second part discusses the metaphors the seafarers use. The study belongs to the field of anthropology of religions which is part of comparative religion.

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In order to fully understand the process of European integration it is of paramount importance to consider developments at the sub-national and local level. EU integration scholars shifted their attention to the local level only at the beginning of the 1990s with the concept of multi-level governance (MLG). While MLG is the first concept to scrutinise the position of local levels of public administration and other actors within the EU polity, I perceive it as too optimistic in the degree of influence it ascribes to local levels. Thus, learning from and combining MLG with other concepts, such as structural constructivism, helps to reveal some of the hidden aspects of EU integration and paint a more realistic picture of multi-level interaction. This thesis also answers the call for more case studies in order to conceptualise MLG further. After a critical study of theories and concepts of European integration, above all, MLG, I will analyse sub-national and local government in Finland and Germany. I show how the sub-national level and local governments are embedded in the EU s multi-level structure of governance and how, through EU integration, those levels have been empowered but also how their scope of action has partially decreased. After theoretical and institutional contextualisation, I present the results of my empirical study of the EU s Community Initiative LEADER+. LEADER stands for Liaison Entre Actions de Développement de l'Économie Rurale , and aims at improving the economic conditions in Europe s rural areas. I was interested in how different actors construct and shape EU financed rural development, especially in how local actors organised in so-called local action groups (LAGs) cooperate with other administrative units within the LEADER+ administrative chain. I also examined intra-institutional relations within those groups, in order to find out who are the most influential and powerful actors within them. Empirical data on the Finnish and German LAGs was first gathered through a survey, which was then supplemented and completed by interviewing LAG members, LAG-managers, several civil servants from Finnish and German decision-making and managing authorities and a civil servant from the EU Commission. My main argument is that in both Germany and Finland, the Community Initiative LEADER+ offered a space for multi-level interaction and local-level involvement, a space that on the one hand consists of highly motivated people actively contributing to the improvement of the quality of life and economy in Europe s countryside but which is dependent and also restricted by national administrative practices, implementation approaches and cultures on the other. In Finland, the principle of tri-partition (kolmikantaperiaatte) in organising the executive committees of LAGs is very noticeable. In comparison to Germany, for instance, the representation of public administration in those committees is much more limited due to this principle. Furthermore, the mobilisation of local residents and the bringing together of actors from the local area with different social and institutional backgrounds to become an active part of LEADER+ was more successful in Finland than in Germany. Tri-partition as applied in Finland should serve as a model for similar policies in other EU member states. EU integration changed the formal and informal inter-institutional relations linking the different levels of government. The third sector including non-governmental institutions and interest groups gained access to policy-making processes and increasingly interact with government institutions at all levels of public administration. These developments do not necessarily result in the empowering of the local level.

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This dissertation is a study of some aspects of theoretical philosophy of the early modern thinker Thomas Hobbes (1588-1679). The focal point of the work is Hobbes s conception of imagination, which is discussed from both a systematic and a historical point of view, as well as in the light of contemporary scholarship. I argue that though there are significant similarities between the view of Hobbes and that of his predecessors, he gives a novel theory of imagination, which clarifies not only early modern discussions on human nature, knowledge, science, and literary criticism, but above all his own versatile philosophy. The prologue of the dissertation introduces methodological principles and gives critical remarks on the standard view of Hobbes. In Chapter II, I discuss the prominent theories of imagination before Hobbes and link them to his account. I argue that though Hobbes adopted the Aristotelian framework, his view is not reduced to it, as he borrows from various sources, for instance, from the Stoics and from Renaissance thought. Chapters III and IV form the psychological part of the work. In the Chapter III I argue that imagination, not sense, is central in the basic cognitive operations of the mind and that imagination has a decisive role in Hobbes s theory of motivation. The Chapter IV concentrates on various questions of Hobbes s philosophy of language. The chapter ends with a defence of a less naturalistic reading of Hobbes s theory of human nature. Chapters V and VI form the epistemological part of the work. I suggest, contrary to what has been recently claimed, that though Hobbes s ideas of good literary style do have a point of contact with his philosophy (e.g. the psychology of creative process), his ideas in the field are independent of his project of demonstrative political science. Instead I argue that the novelty of his major political work, Leviathan (1651), is based on a new theory of knowledge which he continued to develop in the post-Leviathan works. Chapter VII seeks to connect the more theoretical conclusions of Chapters V and VI to Hobbes's idea(l) of science as well as to his philosophical practice. On the basis of Hobbes s own writings as well as some historical examinations, I argue that method is not an apt way to conceptualise Hobbes s philosophical practice. Contemporary readings of Hobbes s theory of science are critically discussed and the chapter ends with an analysis of Hobbes s actual argumentation. In addition to the concluding remarks, the epilogue suggest three things: first, imagination is central when trying to understand Hobbes s versatile philosophy; second, that it is misleading to depict Hobbes as a simple materialist, mechanist, and empiricist; and, third, that in terms of imagination his influence on early modern thought has not been fully appreciated.

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Functional transition theory: administration, legal order and institutions in Russia This dissertation examines some of the salient characteristics of Russia that are deemed to have impeded the growth of its economy and investments in particular. These characteristics are the volatility of the administrative and legal systems, corruption, and the perceived irrationality and difference in the operating environment in comparison with European conditions. The dissertation is one of the first studies on Russia that approaches the subject from the perspective of comprehensive social scientific theories. The study is based on the structural functionalistic theory, which is widely used in the social sciences. Adopting a sufficiently ambitious theoretical examination will provide a systematic and logical explanation of the characteristics of Russian institutions and ways of operations, such as corruption, that are commonly perceived as inexplicable. The approach adopted in the dissertation sheds light on the history of Russia's development and provides a comparative view of other societies in transition. Furthermore, it suggests recommendations as to how the structures of Russian society could be comprehensively strengthened.

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Knowledge-sharing in a teamwork The study examines the link between knowledge-sharing that takes place in a team and the dimensions and objectives of the team s activities. The question the study poses is: How does knowledge-sharing in a team relate to the team s activities? The exchange of knowledge is examined using knowledge-sharing networks and the conversion model, which describes the process of knowledge formation. The answer to the question is sought through four empirical articles describing the activities of a team from the viewpoint of quality, fairness, power related to knowledge management, and performance. One of the articles used in the study describes the role of networks in work life more generally. It attempts to shed light on the manner in which team-related networks operate as part of a more extensive structure of organizational networks. Finland is one of the most eager users of teamwork, if numbers are used as a yardstick. About half of all Finnish wage earners worked in teams in 2009, and comparisons show that the use of teams in Finland is above the EU average. This study focuses on so-called semi-autonomous teams, which carry out permanent work tasks. In such teams, tasks are interdependent, and teams are jointly responsible for ensuring that the work is done. Team members may also, at least to some extent, agree between themselves on how the tasks are carried out and are able to take part in the decision-making process. Such teamwork makes knowledge-sharing an important element for the team s activities. Knowledge and knowledge-sharing have become a major resource, allowing organizations to operate and even compete in today s increasingly competitive markets. A single team or a single organization cannot, however, possess all the knowledge required for carrying out the tasks assigned to it. Although it is difficult to copy the knowledge generated in an organization, it is important to share the knowledge within and between organizations. External links supply teams and organizations with important knowledge that allows them to keep their operations up-to-date and their structures well-functioning. In fact, knowledge provides teams and organizations with an intangible resource that improves their capacity to interact with their environment and to adjust to it. For this reason, it is important to examine both the internal and external knowledge-sharing taking place in a team. The findings of the study show that in terms of quality, fairness, performance and the knowledge management issues concerning a team, its social network structure is both internally and externally connected with its activities. A team structure that is internally coherent and at the same time open to external contacts, is, with certain restrictions, connected with the quality, fairness, and performance of the team. The restrictions concern differences between procedural and interactional justice, public and private sectors, and the team leaders and ordinary team members. The role of the team leader is closely connected with the management of networks that are considered valuable. The results of the study indicate that teamwork is supervisor-dominated. Thus, teamwork does not substantially strengthen the influence of individual employees as players in knowledge-transfer networks. However, ordinary team members possess important peer contacts inside the organization. Teamwork clearly allows employees to interact in a democratic manner, and here the transfer of tacit knowledge plays an important role. Keywords: teamwork, knowledge-sharing, social networks, organization

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Co-stimulatory signals are essential for the activation of naïve T cells and productive immune response. Naïve T cells receive first, antigen-specific signal through T cell receptor. Co-stimulatory receptors provide the second signal which can be either activating or inhibitory. The balance between signals determines the outcome of an immune response. CD28 is crucial for T cell activation; whereas cytotoxic T lymphocyte associated antigen 4 (CTLA4) mediates critical inhibitory signal. Inducible co-stimulator (ICOS) augments cytokine expression and plays role in immunoglobulin class switching. Programmed cell death 1 (PDCD1) acts as negative regulator of T cell proliferation and cytokine responses. The co-stimulatory receptor pathways are potentially involved in self-tolerance and thus, they provide a promising therapeutic strategy for autoimmune diseases and transplantation. The genes encoding CD28, CTLA4 and ICOS are located adjacently in the chromosome region 2q33. The PDCD1 gene maps further, to the region 2q37. CTLA4 and PDCD1 are associated with the risk of a few autoimmune diseases. There is strong linkage disequilibrium (LD) on the 2q33 region; the whole gene of CD28 exists in its own LD block but CTLA4 and the 5' part of ICOS are within a same LD block. The 3' part of ICOS and PDCD1 are in their own separate LD blocks. Extended haplotypes covering the 2q33 region can be identified. This study focuses on immune related conditions like coeliac disease (CD) which is a chronic inflammatory disease with autoimmune features. Immunoglobulin A deficiency (IgAD) belongs to the group of primary antibody deficiencies characterised by reduced levels of immunoglobulins. IgAD co-occurs often with coeliac disease. Renal transplantation is needed in the end stage kidney diseases. Transplantation causes strong immune response which is tried to suppress with drugs. All these conditions are multifactorial with complex genetic background and multiple environmental factors affecting the outcome. We have screened ICOS for polymorphisms by sequencing the exon regions. We detected 11 new variants and determined their frequencies in Finnish population. We have measured linkage disequilibrium on the 2q33 region in Finnish as well as other European populations and observed conserved haplotypes. We analysed genetic association and linkage of the co-stimulatory receptor gene region aiming to study if it is a common risk locus for immune diseases. The 2q33 region was replicated to be linked to coeliac disease in Finnish population and CTLA4-ICOS haplotypes were found to be associated with CD and IgAD being the first non-HLA risk locus common for CD and immunodeficiencies. We also showed association between ICOS and the outcome of kidney transplantation. Our results suggest new evidence for CTLA4-ICOS gene region to be involved in susceptibility of coeliac disease. The earlier published contradictory association results can be explained by involvement of both CTLA4 and ICOS in disease susceptibility. The pattern of variants acting together rather than a single polymorphism may confer the disease risk. These genes may predispose also to immunodeficiencies as well as decreased graft survival and delayed graft function. Consequently, the present study indicates that like the well established HLA locus, the co-stimulatory receptor genes predispose to variety of immune disorders.

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This thesis focuses on how elevated CO2 and/or O3 affect the below-ground processes in semi-natural vegetation, with an emphasis on greenhouse gases, N cycling and microbial communities. Meadow mesocosms mimicking lowland hay meadows in Jokioinen, SW Finland, were enclosed in open-top chambers and exposed to ambient and elevated levels of O3 (40-50 ppb) and/or CO2 (+100 ppm) for three consecutive growing season, while chamberless plots were used as chamber controls. Chemical and microbiological analyses as well as laboratory incubations of the mesocosm soils under different treatments were used to study the effects of O3 and/or CO2. Artificially constructed mesocosms were also compared with natural meadows with regards to GHG fluxes and soil characteristics. In addition to research conducted at the ecosystem level (i.e. the mesocosm study), soil microbial communities were also examined in a pot experiment with monocultures of individual species. By comparing mesocosms with similar natural plant assemblage, it was possible to demonstrate that artificial mesocosms simulated natural habitats, even though some differences were found in the CH4 oxidation rate, soil mineral N, and total C and N concentrations in the soil. After three growing seasons of fumigations, the fluxes of N2O, CH4, and CO2 were decreased in the NF+O3 treatment, and the soil NH4+-N and mineral N concentrations were lower in the NF+O3 treatment than in the NF control treatment. The mesocosm soil microbial communities were affected negatively by the NF+O3 treatment, as the total, bacterial, actinobacterial, and fungal PLFA biomasses as well as the fungal:bacterial biomass ratio decreased under elevated O3. In the pot survey, O3 decreased the total, bacterial, actinobacterial, and mycorrhizal PLFA biomasses in the bulk soil and affected the microbial community structure in the rhizosphere of L. pratensis, whereas the bulk soil and rhizosphere of the other monoculture, A. capillaris, remained unaffected by O3. Elevated CO2 caused only minor and insignificant changes in the GHG fluxes, N cycling, and the microbial community structure. In the present study, the below-ground processes were modified after three years of moderate O3 enhancement. A tentative conclusion is that a decrease in N availability may have feedback effects on plant growth and competition and affect the N cycling of the whole meadow ecosystem. Ecosystem level changes occur slowly, and multiplication of the responses might be expected in the long run.

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Oxysterol binding protein (OSBP) homologues have been found in eukaryotic organisms ranging from yeast to humans. These evolutionary conserved proteins have in common the presence of an OSBP-related domain (ORD) which contains the fully conserved EQVSHHPP sequence motif. The ORD forms a barrel structure that binds sterols in its interior. Other domains and sequence elements found in OSBP-homologues include pleckstrin homology domains, ankyrin repeats and two phenylalanines in an acidic tract (FFAT) motifs, which target the proteins to distinct subcellular compartments. OSBP homologues have been implicated in a wide range of intracellular processes, including vesicle trafficking, lipid metabolism and cell signaling, but little is known about the functional mechanisms of these proteins. The human family of OSBP homologues consists of twelve OSBP-related proteins (ORP). This thesis work is focused on one of the family members, ORP1, of which two variants were found to be expressed tissue-specifically in humans. The shorter variant, ORP1S contains an ORD only. The N-terminally extended variant, ORP1L, comprises a pleckstrin homology domain and three ankyrin repeats in addition to the ORD. The two ORP1 variants differ in intracellular localization. ORP1S is cytosolic, while the ankyrin repeat region of ORP1L targets the protein to late endosomes/lysosomes. This part of ORP1L also has profound effects on late endosomal morphology, inducing perinuclear clustering of late endosomes. A central aim of this study was to identify molecular interactions of ORP1L on late endosomes. The morphological changes of late endosomes induced by overexpressed ORP1L implies involvement of small Rab GTPases, regulators of organelle motility, tethering, docking and/or fusion, in generation of the phenotype. A direct interaction was demonstrated between ORP1L and active Rab7. ORP1L prolongs the active state of Rab7 by stabilizing its GTP-bound form. The clustering of late endosomes/lysosomes was also shown to be linked to the minus end-directed microtubule-based dynein-dynactin motor complex through the ankyrin repeat region of ORP1L. ORP1L, Rab7 and the Rab7-interacting lysosomal protein (RILP) were found to be part of the same effector complex recruiting the dynein-dynactin complex to late endosomes, thereby promoting minus end-directed movement. The proteins were found to be physically close to each other on late endosomes and RILP was found to stabilize the ORP1L-Rab7 interaction. It is possible that ORP1L and RILP bind to each other through their C-terminal and N-terminal regions, respectively, when they are bridged by Rab7. With the results of this study we have been able to place a member of the uncharacterized OSBP-family, ORP1L, in the endocytic pathway, where it regulates motility and possibly fusion of late endosomes through interaction with the small GTPase Rab7.

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Transposable elements, transposons, are discrete DNA segments that are able to move or copy themselves from one locus to another within or between their host genome(s) without a requirement for DNA homology. They are abundant residents in virtually all the genomes studied, for instance, the genomic portion of TEs is approximately 3% in Saccharomyces cerevisiae, 45% in humans, and apparently more than 70% in some plant genomes such as maize and barley. Transposons plays essential role in genome evolution, in lateral transfer of antibiotic resistance genes among bacteria and in life cycle of certain viruses such as HIV-1 and bacteriophage Mu. Despite the diversity of transposable elements they all use a fundamentally similar mechanism called transpositional DNA recombination (transposition) for the movement within and between the genomes of their host organisms. The DNA breakage and joining reactions that underlie their transposition are chemically similar in virtually all known transposition systems. The similarity of the reactions is also reflected in the structure and function of the catalyzing enzymes, transposases and integrases. The transposition reactions take place within the context of a transposition machinery, which can be particularly complex, as in the case of the VLP (virus like particle) machinery of retroelements, which in vivo contains RNA or cDNA and a number of element encoded structural and catalytic proteins. Yet, the minimal core machinery required for transposition comprises a multimer of transposase or integrase proteins and their binding sites at the element DNA ends only. Although the chemistry of DNA transposition is fairly well characterized, the components and function of the transposition machinery have been investigated in detail for only a small group of elements. This work focuses on the identification, characterization, and functional studies of the molecular components of the transposition machineries of BARE-1, Hin-Mu and Mu. For BARE-1 and Hin-Mu transpositional activity has not been shown previously, whereas bacteriophage Mu is a general model of transposition. For BARE-1, which is a retroelement of barley (Hordeum vulgare), the protein and DNA components of the functional VLP machinery were identified from cell extracts. In the case of Hin-Mu, which is a Mu-like prophage in Haemophilus influenzae Rd genome, the components of the core machinery (transposase and its binding sites) were characterized and their functionality was studied by using an in vitro methodology developed for Mu. The function of Mu core machinery was studied for its ability to use various DNA substrates: Hin-Mu end specific DNA substrates and Mu end specific hairpin substrates. The hairpin processing reaction by MuA was characterized in detail. New information was gained of all three machineries. The components or their activity required for functional BARE-1 VLP machinery and retrotransposon life cycle were present in vivo and VLP-like structures could be detected. The Hin-Mu core machinery components were identified and shown to be functional. The components of the Mu and Hin-Mu core machineries were partially interchangeable, reflecting both evolutionary conservation and flexibility within the core machineries. The Mu core machinery displayed surprising flexibility in substrate usage, as it was able to utilize Hin-Mu end specific DNA substrates and to process Mu end DNA hairpin substrates. This flexibility may be evolutionarily and mechanistically important.

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Cortinarius is the largest genus of Agaricales with a worldwide distribution. So far, over 4000 Cortinarius names and combinations have been published. Cortinarius spp. form ectomycorrhizae with different trees and shrubs. A majority of the Cortinarius species have narrow ecological preferences and many form ectomycorrhiza with only one or few host species. The subgenus Telamonia sensu lato (s. lat.), comprising the greatest number of species, is the most poorly known of the subgenera of Cortinarius. The centre of diversity is in the northern hemisphere, although some species of the group are also recognized in the southern hemisphere. The aim of this thesis was to study the taxonomy of Cortinarius subgenus Telamonia p.p. species based on morphological and molecular data, as well as to study the ecology and distribution of the species in North Europe. The taxonomical problems encountered and the difficulty in finding and studying all the relevant names and types slowed down the study. The diversity of the subgenus Telamonia s. lat. in North Europe (excluding sect. Hydrocybe, Icrustati and Anomali) was found to be far greater than previously thought. Even many of the common species have not yet been described. So far, ca. 200 species have been recognised from the Nordic countries, but the sampling in most groups does not cover the whole diversity and especially the southern deciduous forest species are underrepresented in our study. In most cases phylogenetic (only based on ITS data) and morphological species recognition were in concordance, but in a few cases morphologically delimited species had almost identical ITS sequences, raising the question as to whether ITS is always variable enough for species recognition. The opposite situation, in which a morphologically uniform species included two phylogenetically distinct lineages, however, was also encountered, suggesting the possibility of cryptic species in Cortinarius. In our studies no taxa below species level were recognised and the aforementioned results indicate that presumably they can only be recognised genetically. Based on our preliminary results a revision of the infrageneric classification in Cortinarius subgenus Telamonia s. lat. is needed, and more sections should be established for a meaningful and functional classification. Many groups have turned out to be artificial, and it seems evident that many characteristics have been over- or underemphasised. Many morphological characteristics, however, are useful in the identification of telamonioid species and e.g. some spore characteristics have often been overlooked. Our studies have concentrated on North Europe, but we have found some similarities with North European and North American taxa.

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The circulatory system consists of the blood and lymphatic vessels. While blood vessels transport oxygen, cells, and nutrients to tissues, the lymphatic vessels collect fluid, cells, and plasma proteins from tissues to return back to the blood circulation. Angiogenesis, the growth of new blood vessels from pre-existing ones, is an important process involved in several physiological conditions such as inflammation, wound healing, and embryonic development. Furthermore, angiogenesis is found in many pathological conditions such as atherosclerosis and the growth and differentiation of solid tumors. Many tumor types spread via lymphatic vessels to form lymph node metastasis. The elucidation of the molecular players coordinating development of the vascular system has provided an array of tools for further insight of the circulatory system. The discovery of the Vascular Endothelial Growth Factor (VEGF) family members and their tyrosine kinase receptors (VEGFRs) has facilitated the understanding of the vasculature in different physiological and pathological situations. The VEGFRs are expressed on endothelial cells and mediate the growth and maintenance of both the blood and lymphatic vasculatures. This study was undertaken to address the role of VEGFR-2 specific signaling in maturation of blood vessels during neoangiogenesis and in lymphangiogenesis. We also wanted to differentiate between VEGFR-2 and VEGFR-3 specific signaling in lymphangiogenesis. We found that specific VEGFR-2 stimulation alone by gene therapeutic methods is not sufficient for production of mature blood vessels. However, VEGFR-2 stimulation in combination with expression of platelet-derived growth factor D (PDGF-D), a recently identified member of the PDGF growth factor family, was capable of stabilizing these newly formed vessels. Signaling through VEGFR-3 is crucial during developmental lymphangiogenesis, but we showed that the lymphatic vasculature becomes independent of VEGFR-3 signaling after the postnatal period. We also found that VEGFR-2 specific stimulation cannot rescue the loss of lymphatic vessels when VEGFR-3 signaling is blocked and that VEGFR-2 specific signals promote lymphatic vessel enlargement, but are not involved in vessel sprouting to generate new lymphatic vessels in vivo, in contrast to the VEGFR-2 dependent sprouting observed in blood vessels. In addition, we compared the inhibitory effects of a small molecular tyrosine kinase inhibitor of VEGFR-2 vs. VEGFR-3 specific signaling in vitro and in vivo. Our results showed that the tyrosine kinase inhibitor could equally affect physiological and pathological processes dependent on VEGFR-2 and VEGFR-3 driven angiogenesis or lymphangiogenesis. These results provide new insights into the VEGFR specific pathways required for pre- and postnatal angiogenesis as well as lymphangiogenesis, which could provide important targets and therapies for treatment of diseases characterized by abnormal angiogenesis or lymphangiogenesis.

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Erwinia carotovora subsp. carotovora (Ecc) is a Gram-negative enterobacterium that causes soft-rot in potato and other crops. The main virulence determinants, the extracellular plant cell wall -degrading enzymes (PCWDEs), lead to plant tissue maceration. In order to establish a successful infection the production of PCWDEs are controlled by a complex regulatory network, including both specific and global activators and repressors. One of the most important virulence regulation systems in Ecc is mediated by quorum sensing (QS), which is a population density -dependent cell-to-cell communication mechanism used by many Gram-negative bacteria. In these bacteria N-acylhomoserine lactones (AHSL), act as diffusible signaling molecules enabling communication between bacterial cells. The AHSLs are structurally diverse and differ in their acyl chain length. This gives the bacteria signaling specificity and enables the recognition and communication within its own species. In order to detect and respond to the AHSLs the bacteria use QS regulators, LuxR-type proteins. The aim of this study was to get a deeper understanding of the Ecc QS system. In the first part of the study we showed that even different strains of Ecc use different dialects and of physiological concentrations, only the cognate AHSL with the correct acyl chain is recognized as a signal that can switch on virulence genes. The molecular basis of the substrate specificity of the AHSL synthase ExpI was investigated in order to recognize the acyl chain length specificity determinants of distinct AHSL synthases. Several critical residues that define the size of the substrate-binding pocket were identified. We demonstrated that in the ExpISCC1 mutations M127T and F69L are sufficient to change the N-3-oxohexanoyl-L-homoserine lactone producing ExpISCC1 to an N-3-oxooctanoyl-L-homoserine lactone (3-oxo-C8-HSL) producing enzyme. In the second study the means of sensing specificity and response to the AHSL signaling molecule were investigated. We demonstrated that the AHSL receptor ExpR1 of Ecc strain SCC3193 has strict specificity for the cognate AHSL 3-oxo-C8-HSL. In addition we identified a second AHSL receptor ExpR2 with a novel property to sense AHSLs with different acyl chain lengths. In the absence of AHSLs ExpR1 and ExpR2 were found to act synergistically to repress the virulence gene expression. This repression was shown to be released by addition of AHSLs and appears to be largely mediated by the global negative regulator RsmA. In the third study random transposon mutagenesis was used to widen the knowledge of the Ecc QS regulon. Two new QS-controlled target genes, encoding a DNA-binding regulator Hor and a plant ferredoxin-like protein FerE, were identified. The QS control of the identified genes was executed by the QS regulators ExpR1 and ExpR2 and as expression of PCWDE genes mediated by the RsmA repressor. Hor was shown to contribute to bacterial virulence at least partly through its control of PCWDE production, while FerE was shown to contribute to oxidative stress tolerance and in planta fitness of the bacteria. In addition our results suggest that QS is central to the control of oxidative stress tolerance in Ecc. In conclusion, these results indicate that Ecc strain SCC3193 is able to react and respond both to the cognate AHSL signal and the signals produced by other bacterial species, in order to control a wide variety of functions in the plant pathogen Ecc.

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Trimeric autotransporters are a family of secreted outer membrane proteins in Gram-negative bacteria. These obligate homotrimeric proteins share a conserved C-terminal region, termed the translocation unit. This domain consists of an integral membrane β-barrel anchor and associated α-helices which pass through the pore of the barrel. The α-helices link to the extracellular portion of the protein, the passenger domain. Autotransportation refers to the way in which the passenger domain is secreted into the extracellular space. It appears that the translocation unit mediates the transport of the passenger domain across the outer membrane, and no external factors, such as ATP, ion gradients nor other proteins, are required. The passenger domain of autotransporters contains the specific activities of each protein. These are usually related to virulence. In trimeric autotransporters, the main function of the proteins is to act as adhesins. One such protein is the Yersinia adhesin YadA, found in enteropathogenic species of Yersinia. The main activity of YadA from Y. enterocolitica is to bind collagen, and it also mediates adhesion to other molecules of the extracellular matrix. In addition, YadA is involved in serum resistance, phagocytosis resistance, binding to epithelial cells and autoagglutination. YadA is an essential virulence factor of Y. enterocolitica, and removal of this protein from the bacteria leads to avirulence. In this study, I investigated the YadA-collagen interaction by studying the binding of YadA to collagen-mimicking peptides by several biochemical and biophysical methods. YadA bound as tightly to the triple-helical model peptide (Pro-Hyp-Gly)10 as to native collagen type I. However, YadA failed to bind a similar peptide that does not form a collagenous triple helix. As (Pro-Hyp-Gly)10 does not contain a specific sequence, we concluded that a triple-helical conformation is necessary for YadA binding, but no specific sequence is required. To further investigate binding determinants for YadA in collagens, I examined the binding of YadA to a library of collagen-mimicking peptides that span the entire triple-helical sequences of human collagens type II and type III. YadA bound promiscuously to many but not all peptides, indicating that a triple-helical conformation alone is not sufficient for binding. The high-binding peptides did not share a clear binding motif, but these peptides were rich in hydroxyproline residues and contained a low number of charged residues. YadA thus binds collagens without sequence specificity. This strategy of promiscuous binding may be advantageous for pathogenic bacteria. The Eib proteins from Escherichia coli are immunoglobulin (Ig)-binding homologues of YadA. I showed conclusively that recombinant EibA, EibC, EibD and EibF bind to IgG Fc. I crystallised a fragment of the passenger domain of EibD, which binds IgA in addition to IgG. The structure has a YadA-like head domain and an extended coiled-coil stalk. The top half of the coiled-coil is right-handed with hendecad periodicity, whereas the lower half is a canonical left-handed coiled-coil. At the transition from right- to left-handedness, a small β-sheet protrudes from each monomer. I was able to map the binding regions for IgG and IgA using truncations and site-directed mutagenesis to the coiled-coil stalk and identified residues critical for Ig binding.