93 resultados para second central moment


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Maurice Blanchot (1907-2003), the French writer and novelist, is one of the most important figures in post-war French literature and philosophy. The main intention of this study is to figure out his position and originality in the field of phenomenology. Since this thesis concentrates on the notion of vision in Blanchot s work, its primary context is the post-war discussion of the relation between seeing and thinking in France, and particularly the discussion of the conditions of non-violent vision and language. The focus will be on the philosophical conversation between Blanchot and his contemporary philosophers. The central premise is the following: Blanchot relates the criticism of vision to the criticism of the representative model of language. In this thesis, Blanchot s definition of literary language as the refusal to reveal anything is read as a reference pointing in two directions. First, to Hegel s idea of naming as negativity which reveals Being incrementally to man, and second, to Heidegger s idea of poetry as the simultaneity of revealing and withdrawal; the aim is to prove that eventually Blanchot opposes both Hegel s idea of naming as a gradual revelation of the totality of being and Heidegger s conception of poetry as a way of revealing the truth of Being. My other central hypothesis is that for Blanchot, the criticism of the privilege of vision is always related to the problematic of the exteriority. The principal intention is to trace how Blanchot s idea of language as infinity and exteriority challenges both the Hegelian idea of naming as conceptualizing things and Heidegger s concept of language as a way to truth (as aletheia). The intention is to show how Blanchot, with his concepts of fascination, resemblance and image, both affirms and challenges the central points of Heidegger s thinking on language. Blanchot s originality in, and contribution to, the discussion about the violence of vision and language is found in his answer to the question of how to approach the other by avoiding the worst violence . I claim that by criticizing the idea of language as naming both in Hegel and Heidegger, Blanchot generates an account of language which, since it neither negates nor creates Being, is beyond the metaphysical opposition between Being and non-Being.

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The thesis is about Finnish freestyle-rap, a modern form of oral poetry producing improvised rap lyrics at the moment of performance. The research material consists of interviews with seven freestyle experts and a DVD from Finnish Rap Championships 2005 containing freestyle-rap. The thesis has three goals: describing the different variations or subgenres of freestyle, outlining the esthetics and register of freestyle, and examining the composition of freestyle. The research material acts a central role in the thesis but the theoretical framework is also wide: cornerstones are John Miles Foley's register analysis, oral formulaic theory and William Levelt's psycholinguistic theory on planning of speech. Freestyle is divided into three partially overlapping genres with slight variation in conventions. The genres are freestyle battle, cypher, and live freestyle. Freestyle's esthetics are composed of certain qualities and preferences: the rhyme is a syllabically repeating vocal rhyme. The rapping must be synchronised with the background rhythm and the rhyme comes in the end of the line. The lyrics must be somehow anchored to the surroundings and the moment of performance. The style of rapping, ie. flow, has to be personal one way or the other. Individual formulas are used to some extent in freestyle compostition. When planning the lines, all other content is subordinate to the rhyme, whose phonetic processing is the primary act in the planning of freestyle. This discovery sets Levelt's theory open to doubt.

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This thesis is an empirical study of how two words in Icelandic, "nú" and "núna", are used in contemporary Icelandic conversation. My aims in this study are, first, to explain the differences between the temporal functions of "nú" and "núna", and, second, to describe the non-temporal functions of "nú". In the analysis, a focus is placed on comparing the sequential placement of the two words, on their syntactical distribution, and on their prosodic realization. The empirical data comprise 14 hours and 11 minutes of naturally occurring conversation recorded between 1996 and 2003. The selected conversations represent a wide range of interactional contexts including informal dinner parties, institutional and non-institutional telephone conversations, radio programs for teenagers, phone-in programs, and, finally, a political debate on television. The theoretical and methodological framework is interactional linguistics, which can be described as linguistically oriented conversation analysis (CA). A comparison of "nú" and "núna" shows that the two words have different syntactic distributions. "Nú" has a clear tendency to occur in the front field, before the finite verb, while "núna" typically occurs in the end field, after the object. It is argued that this syntactic difference reflects a functional difference between "nú" and "núna". A sequential analysis of "núna" shows that the word refers to an unspecified period of time which includes the utterance time as well as some time in the past and in the future. This temporal relation is referred to as reference time. "Nú", by contrast, is mainly used in three different environments: a) in temporal comparisons, 2) in transitions, and 3) when the speaker is taking an affective stance. The non-temporal functions of "nú" are divided into three categories: a) "nú" as a tone particle, 2) "nú" as an utterance particle, and 3) "nú" as a dialogue particle. "Nú" as a tone particle is syntactically integrated and can occur in two syntactic positions: pre-verbally and post-verbally. I argue that these instances are employed in utterances in which a speaker is foregrounding information or marking it as particularly important. The study shows that, although these instances are typically prosodically non-prominent and unstressed, they are in some cases delivered with stress and with a higher pitch than the surrounding talk. "Nú" as an utterance particle occurs turn-initially and is syntactically non-integrated. By using "nú", speakers show continuity between turns and link new turns to prior ones. These instances initiate either continuations by the same speaker or new turns after speaker shifts. "Nú" as a dialogue particle occurs as a turn of its own. The study shows that these instances register informings in prior turns as unexpected or as a departure from the normal state of affairs. "Nú" as a dialogue particle is often delivered with a prolonged vowel and a recognizable intonation contour. A comparative sequential and prosodic analysis shows that in these cases there is a correlation between the function of "nú" and the intonation contour by which it is delivered. Finally, I argue that despite the many functions of "nú", all the instances can be said to have a common denominator, which is to display attention towards the present moment and the utterances which are produced prior or after the production of "nú". Instead of anchoring the utterances in external time or reference time, these instances position the utterance in discourse internal time, or discourse time.

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The study describes the use and meaning of the Finnish demonstrative pronouns, focus being on the pronoun "tämä" (roughly 'this'). The Finnish demonstrative system is a three way one, the other two demonstratives are "tuo" ('that') and "se" ('it'). The data consisted of 12 half hours of video- and tape-recorded face-to-face and telephone conversations. The method for the study was ethnomethodological conversation analysis (CA); in addition to CA, the theoretical framework consisted of functional linguistics and linguistic anthropology. First, the study dealt with the syntactic distribution of the three demonstratives. The pronouns were analysed according to whether they are before or after the verb, and whether they compose an NP on their own or are determinants of a lexical NP. The study suggested that the form and the placement of the NP presents the referent as continuous/discontinuous or given/new. Givenness of a referent was defined as "identified adequately for the purposes of the on-going action". The so-called dislocated utterances were considered separately. It was found that left-dislocations are used for inserting referents in a particular relation to the on-going activity. Right-dislocations offer a solution for the sometimes competing motivations of newness and continuity: they are used for securing the identifiability of a referent that is implied to be continuous. Second, the study focussed on analysing the meaning of the pronouns according to three dimensions of reference: referential, indexical and relational. It was found that the demonstratives can organize interactional or spatial context. When organizing interactional context, the demonstrative pronouns express the role of identifying the referent in relation to the on-going activity. The pronoun "tämä" expresses that the referent is referentially open and the characterization of the referent is given in the on-going turn. Furthermore, it expresses asymmetry of the indexical ground: it expresses that the participants of a conversation do not share a mutual understanding of the activity at that particular time. In addition, the referent of the pronoun "tämä" is central for understanding the on-going action. Centrality could be understood as the relational feature of the pronoun. However, it is a consequence of the referential and indexical features of "tämä". The pronoun "tuo" also expresses referential openness, but it implies indexical symmetry. The pronoun "se" implies that the referent is known enough, and implies indexical symmetry. When used spatially, the pronouns may refer to a physical space or to a situation. They express or imply that the speaker is inside or outside the referent. The pronoun "tämä" implies inclusion, and the pronoun "tuo" expresses exclusion.

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The Struggle for Eros: On Love and Gender in the Pahlen Series The present dissertation examines how gender, sexuality and motherhood are constructed in the novel series Fröknarna von Pahlen (The Misses von Pahlen, I VII, 1930 1935) by the Swedish author Agnes von Krusenstjerna. The aim of the study is to analyze how the Pahlen series relates to the discourses on gender and sexuality circulating in the 1930s, and how the series opens a dialogue with the feminist thinking of the time especially with the book Lifslinjer I (Love and Marriage, 1903) by the Swedish author Ellen Key. Fröknarna von Pahlen holds a central position in the research on Agnes von Krusenstjerna partly due to the literary debate that the novel series triggered. The debate was connected to the development taking place in the Swedish society in the beginning of the 1930s, in the so-called second phase of the Modern Breakthrough. Sweden was at that time characterized by struggle over the definitions of gender, sexuality and parenthood, and this struggle is also visible in the Pahlen series. The literary debate took place in 1934 1935 and it began after an article by the modernist writer Karin Boye was published in Social-Demokraten on 28 January 1934. In her polemic article, Boye saw the Pahlen series as a sign that the family institution is on the verge of a breakdown and with it the whole moral system that has come to existence through it . Boye went on to state that Krusenstjerna only sees and describes and that she explores neither new literary forms nor new values. Boye wrote the article before the last two parts of the novel series were published, so obviously she could not discuss the utopian vision characterizing those parts. This study, however, strives to demonstrate that Krusenstjerna not only sees and describes, but that she like many of her contemporary female colleagues appears to take the request of Friedrich Nietzsche to revaluate all values seriously. Like the works of her contemporaries, Krusenstjerna s Pahlen series is marked by a double vision on the one hand a critique of the prevailing social order, and on the other hand a dream of a new world and a new human being. In this research the vision of the Pahlen series is characterized as queer in order to emphasize that the series not only criticizes the prevailing gender order and its morals, but is also open for new ways of doing gender, parenthood, and family.

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The historical development of Finnish nursing textbooks from the late 1880s to 1967: the training of nurses in the Foucauldian perspective. This study aims, first, to analyse the historical development of Finnish nursing textbooks in the training of nurses and in nursing education: what Foucauldian power processes operate in the writing and publishing processes? What picture of nursing did early nursing books portray and who were the decision makers? Second, this study also aims to analyse the processes of power in nurse training processes. The time frame extends from the early stages of nurse training in the late 1880s to 1967. This present study is a part of textbook research and of the history of professional education in Finland. This study seeks to explain how, who or what contributed the power processes involved in the writing of nursing textbooks and through textbooks. Did someone use these books as a tool to influence nursing education? The third aim of this study is to define and analyse the purpose of nurse training. Michel Foucault´s concept of power served as an explanatory framework for this study. A very central part of power is the assembling of data, the supplying of information and messages, and the creation of discourses. When applied to the training of nurses, power dictates what information is taught in the training and contained in the books. Thus, the textbook holds an influential position as a power user in these processes. Other processes in which such power is exercised include school discipline and all other normalizing processes. One of most powerful ways of adapting is the hall of residence, where nursing pupils were required to live. Trained nurses desired to separate themselves from their untrained predecessors and from those with less training by wearing different uniforms and living in separate housing units. The state supported the registration of trained nurses by legislation. With this decision the state made it illegal to work as a nurse without an authorised education, and use these regulations to limit and confirm the professional knowledge and power of nurses. Nurses, physicians and government authorities used textbooks in nursing education as tools to achieve their own purposes and principles. With these books all three groups attempted to confirm their own professional power and knowledge while at the same time limit the power and expertise of others. Public authorities sought to unify the training of nurses and the basis of knowledge in all nursing schools in Finland with similar and obligatory textbooks. This standardisation started 20 years before the government unified nursing training in 1930. The textbooks also served as data assemblers in unifying nursing practices in Finnish hospitals, because the Medical Board required all training hospitals to attach the textbooks to units with nursing pupils. For the nurses, and especially for the associations of Finnish nurses, making and publishing their own textbooks for the training of nurses was a part of their professional projects. With these textbooks, the nursing elite and the teachers tended to prepare nursing pupils’ identities for nursing’s very special mission. From the 1960s, nursing was no longer understood as a mission, but as a normal vocation. Nurses and doctors disputed this view throughout the period studied, which was the optimal relationship between theory and practice in nursing textbooks and in nurse education. The discussion of medical knowledge in nursing textbooks took place in the 1930s and 1940s. Nurses were very confused about their own professional knowledge and expertise, which explains why they could not create a new nursing textbook despite the urgency. A brand new nursing textbook was published in 1967, about 30 years after the predecessor. Keyword: nurse, nurse training, nursing education, power, textbook, Michel Foucault

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This dissertation investigates changes in bank work and the experience of impossibility attached to these by workers at the local level from the viewpoint of work-related well-being and collective learning. A special challenge in my work is to conceptualize the experience of impossibility as related to change, and as a starting point and tool for development work. The subject of the dissertation, solving the impossible as a collective learning process, came up as a central theme in an earlier project: Work Units between the Old and the New (1997 – 1999). Its aim was to investigate how change is constructed as a long-term process, starting from the planning of the change until its final realization in everyday banking work. I studied changes taking place in the former Postipankki (Postal Bank), later called Leonia. The three-year study involved the Branch Office of Martinlaakso, and was conducted from the perspective of well-being in a change process. The sense of impossibility involved in changes turned out to be one of the most crucial factors impairing the sense of well-being. The work community that was the target of my study did not have the available tools to construct the change locally, or to deal with the change-related impossibility by solving it through a mutual process among themselves. During the last year of the project, I carried out an intervention for development in the Branch Office, as collaboration between the researchers and the workers. The purpose of the intervention was to resolve such perceived change-related impossibility as experienced repeatedly and considered by the work community as relevant to work-related well-being. The documentation of the intervention – audio records from development sessions, written assignments by workers and assessment or evaluation interviews – constitute the essential data for my dissertation. The earlier data, collected and analysed during the first two years, provides a historical perspective on the process, all the way from construction of the impossibility towards resolving and transcending it. The aim of my dissertation is to understand the progress of developmental intervention as a shared, possibly expansive learning process within a work community and thus to provide tools for perceiving and constructing local change. I chose the change-related impossibility as a starting point for development work in the work community and as a target of conceptualization. This, I feel, is the most important contribution of my dissertation. While the intervention was in progress, the concept of impossibility started emerging as a stimulating tool for development work. An understanding of such a process can be applied to development work outside banking work as well. According to my results, it is pivotal that a concept stimulating development is strongly connected with everyday experiences of and speech about changes in work activity, as well as with the theoretical framework of work development. During this process, development work on a local level became of utmost interest as a case study for managing change. Theoretically, this was conceptualized as so-called second-order work and this concept accompanies us all the way through the research process. Learning second-order work and constructing tools based on this work have proved crucial for promoting well-being in the change circumstances in a local work unit. The lack of second-order work has led to non-well-being and inability to transcend the change-related sense of impossibility in the work community. Solving the impossible, either individually or situationally, did not orient the workers towards solving problems of impossibility together as a work community. Because the experience of the impossibility and coming to terms with transcending it are the starting point and the target of conceptualization in this dissertation, the research provides a fresh viewpoint on the theoretical framework of change and developmental work. My dissertation can facilitate construction of local changes necessitated by the recent financial crisis, and thus promote fluency and well-being in work units. It can also support change-related well-being in other areas of working life.

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This thesis studies the experiences of women who have lived in a youth home as girls. There are two main themes: 1) experiences of living in a youth home, and 2) experiences of coping as an adult. Data on the first theme is purely subjective; it derives from personal, recalled experiences. Data on the second theme is partly based on experiences and partly on facts about the current life situation of the research participants. A third theme of the thesis is concerned with the question of how the research participants’ placement in a youth home influenced their later life. The thesis contributes valuable knowledge concerning the experiences of young people who have been raised in substitute care, a topic that is rare in the literature. The empirical data of the study consists of responses to an initial inquiry and subsequent interviews. The inquiry was sent to 116 former inhabitants of a youth home. 62 altogether returned the inquiry, and 34 participated in the interview. The purpose of the inquiry was to produce an overview of the life situations of the research participants and to invite them to participate in the interview. In addition, the inquiry sought to produce an overview of how the participants enjoyed living in a youth home and how they saw its significance in terms of their later lives. The interviews concentrated on the research participants’ experiences concerning the processes of getting into a youth home, living there, and coping independently in life afterwards. The most central result relating to the first main theme was that the experiences were both shared and non-shared. Living in a youth home was characterized by six general sentiments: “wonderful, real home”, “new world!”, “safe haven”, “place to live”, “penal institution”, and “nightmare”. These sentiments seemed to be related first and foremost to whether one’s own, individual needs and expectations had been met in the youth home. The strongest and most common needs, as experienced, were the needs for safety, belongingness and respect. On the basis of the experiences, meeting these needs can be considered as the most important task of a youth home. The results relating to the second main theme of the study were examined in two different ways. Comparisons with the general female population (education, situation in working life and financial circumstances) showed that research participants had coped less well. Differences were also found to exist in family structures: nuclear families and single mother families were more unusual among research participants, and stepfamilies more common, than in the general population. More of the participants’ children than of the general population’s lived with somebody other than their parent. However, the experience of coping well was common among research participants, although the beginning of independent living had been generally experienced as difficult: feelings of loneliness, insecurity and restlessness were dominant. Later, a sense of life control developed and strengthened through joining with others (family, work, friends), through accepting one’s own life history and through creating one’s own model of living. As the most significant explanation of their coping, the research participants identified their own (innate) strength and will to cope. The majority of the research participants felt that the youth home had a positive influence on their later lives. Positive influences can be grouped in three “levels”: I) getting out of the home, II) having good experiences and learning useful things, and III) the essential effect on one’s own way of thinking and living. The second level’s influence includes strengthened self-esteem, increased social understanding and new knowledge and skills. Some research participants did not think the youth home had any significance in terms of their later lives, and some thought it had negative significance.

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The earliest stages of human cortical visual processing can be conceived as extraction of local stimulus features. However, more complex visual functions, such as object recognition, require integration of multiple features. Recently, neural processes underlying feature integration in the visual system have been under intensive study. A specialized mid-level stage preceding the object recognition stage has been proposed to account for the processing of contours, surfaces and shapes as well as configuration. This thesis consists of four experimental, psychophysical studies on human visual feature integration. In two studies, classification image a recently developed psychophysical reverse correlation method was used. In this method visual noise is added to near-threshold stimuli. By investigating the relationship between random features in the noise and observer s perceptual decision in each trial, it is possible to estimate what features of the stimuli are critical for the task. The method allows visualizing the critical features that are used in a psychophysical task directly as a spatial correlation map, yielding an effective "behavioral receptive field". Visual context is known to modulate the perception of stimulus features. Some of these interactions are quite complex, and it is not known whether they reflect early or late stages of perceptual processing. The first study investigated the mechanisms of collinear facilitation, where nearby collinear Gabor flankers increase the detectability of a central Gabor. The behavioral receptive field of the mechanism mediating the detection of the central Gabor stimulus was measured by the classification image method. The results show that collinear flankers increase the extent of the behavioral receptive field for the central Gabor, in the direction of the flankers. The increased sensitivity at the ends of the receptive field suggests a low-level explanation for the facilitation. The second study investigated how visual features are integrated into percepts of surface brightness. A novel variant of the classification image method with brightness matching task was used. Many theories assume that perceived brightness is based on the analysis of luminance border features. Here, for the first time this assumption was directly tested. The classification images show that the perceived brightness of both an illusory Craik-O Brien-Cornsweet stimulus and a real uniform step stimulus depends solely on the border. Moreover, the spatial tuning of the features remains almost constant when the stimulus size is changed, suggesting that brightness perception is based on the output of a single spatial frequency channel. The third and fourth studies investigated global form integration in random-dot Glass patterns. In these patterns, a global form can be immediately perceived, if even a small proportion of random dots are paired to dipoles according to a geometrical rule. In the third study the discrimination of orientation structure in highly coherent concentric and Cartesian (straight) Glass patterns was measured. The results showed that the global form was more efficiently discriminated in concentric patterns. The fourth study investigated how form detectability depends on the global regularity of the Glass pattern. The local structure was either Cartesian or curved. It was shown that randomizing the local orientation deteriorated the performance only with the curved pattern. The results give support for the idea that curved and Cartesian patterns are processed in at least partially separate neural systems.

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This study examines supervisors' emerging new role in a technical customer service and home customers division of a large Finnish telecommunications corporation. Data of the study comes from a second-generation knowledge management project, an intervention research, which was conducted for supervisors of the division. The study exemplifies how supervision work is transforming in high technology organization characterized with high speed of change in technologies, products, and in grass root work practices. The intervention research was conducted in the division during spring 2000. Primary analyzed data consists of six two-hour videorecorded intervention sessions. Unit of analysis has been collective learningactions. Researcher has first written conversation transcripts out of the video-recorded meetings and then analyzed this qualitative data using analytical schema based on collective learning actions. Supervisors' role is conceptualized as an actor of a collective and dynamic activity system, based on the ideas from cultural historical activity theory. On knowledge management researcher has takena second-generation knowledge management viewpoint, following ideas fromcultural historical activity theory and developmental work research. Second-generation knowledge management considers knowledge embedded and constructed in collective practices, such as innovation networks or communities of practice (supervisors' work community), which have the capacity to create new knowledge. Analysis and illustration of supervisors' emerging new role is conceptualized in this framework using methodological ideas derived from activity theory and developmental work research. Major findings of the study show that supervisors' emerging new role in a high technology telecommunication organization characterized with high speed of discontinuous change in technologies, products, and in grass-root practices cannot be defined or characterized using a normative management role/model. Their role is expanding two-dimensionally, (1) socially and (2) in new knowledge, and work practices. The expansion in organization and inter-organizational network (social expansion) causes pressures to manage a network of co-operation partners and subordinates. On the other hand, the faster speed of change in technological solutions, new products, and novel customer wants (expansion in knowledge) causes pressures for supervisors to innovate quickly new work practices to manage this change. Keywords: Activity theory, knowledge management, developmental work research, supervisors, high technology organizations, telecommunication organizations, second-generation knowledge management, competence laboratory, intervention research, learning actions.

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The present study addressed the epistemology of teachers’ practical knowledge. Drawing from the literature, teachers’ practical knowledge is defined as all teachers’ cognitions (e.g., beliefs, values, motives, procedural knowing, and declarative knowledge) that guide their practice of teaching. The teachers’ reasoning that lies behind their practical knowledge is addressed to gain insight into its epistemic nature. I studied six class teachers’ practical knowledge; they teach in the metropolitan region of Helsinki. Relying on the assumptions of the phenomenographic inquiry, I collected and analyzed the data. I analyzed the data in two stages where the first stage involved an abductive procedure, and the second stage an inductive procedure for interpretation, and thus developed the system of categories. In the end, a quantitative analysis nested into the qualitative findings to study the patterns of the teachers’’ reasoning. The results indicated that teachers justified their practical knowledge based on morality and efficiency of action; efficiency of action was found to be presented in two different ways: authentic efficiency and naïve efficiency. The epistemic weight of morality was embedded in what I call “moral care”. The core intention of teachers in the moral care was the commitment that they felt about the “whole character” of students. From this perspective the “dignity” and the moral character of the students should not replaced for any other “instrumental price”. “Caring pedagogy” was the epistemic value of teachers’ reasoning in the authentic efficiency. The central idea in the caring pedagogy was teachers’ intentions to improve the “intellectual properties” of “all or most” of the students using “flexible” and “diverse” pedagogies. However, “regulating pedagogy” was the epistemic condition of practice in the cases corresponding to naïve efficiency. Teachers argued that an effective practical knowledge should regulate and manage the classroom activities, but the targets of the practical knowledge were mainly other “issues “or a certain percentage of the students. In these cases, the teachers’ arguments were mainly based on the notion of “what worked” regardless of reflecting on “what did not work”. Drawing from the theoretical background and the data, teachers’ practical knowledge calls for “praxial knowledge” when they used the epistemic conditions of “caring pedagogy” and “moral care”. It however calls for “practicable” epistemic status when teachers use the epistemic condition of regulating pedagogy. As such, praxial knowledge with the dimensions of caring pedagogy and moral care represents the “normative” perspective on teachers’ practical knowledge, and thus reflects a higher epistemic status in comparison to “practicable” knowledge, which represents a “descriptive” perception toward teachers’ practical knowledge and teaching.

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Catechol-O-methyltransferase (COMT) metabolizes catecholamines such as dopamine (DA), noradrenaline (NA) and adrenaline, which are vital neurotransmitters and hormones that play important roles in the regulation of physiological processes. COMT enzyme has a functional Val158Met polymorphism in humans, which affects the subjects COMT activity. Increasing evidence suggests that this functional polymorphism may play a role in the etiology of various diseases from schizophrenia to cancers. The aim of this project was to provide novel biochemical information on the physiological and especially pathophysiological roles of COMT enzyme as well as the effects of COMT inhibition in the brain and in the cardiovascular and renal system. To assess the roles of COMT and COMT inhibition in pathophysiology, we used four different study designs. The possible beneficial effects of COMT inhibition were studied in double-transgenic rats (dTGRs) harbouring human angiotensinogen and renin genes. Due to angiotensin II (Ang II) overexpression, these animals exhibit severe hypetension, cardiovascular and renal end-organ damage and mortality of approximately 25-40% at the age of 7-weeks. The dTGRs and their Sprague-Dawley controls tissue samples were assessed with light microscopy, immunohistochemistry, reverse transcriptase-polymerase chain reaction (RT-PCR) and high-pressure liquid chromatography (HPLC) to evaluate the tissue damages and the possible protective effects pharmacological intervention with COMT inhibitors. In a second study, the consequence of genetic and pharmacological COMT blockade in blood pressure regulation during normal and high-sodium was elucidated using COMT-deficient mice. The blood pressure and the heart rate were measured using direct radiotelemetric blood pressure surveillance. In a third study, the effects of acute and subchronic COMT inhibition during combined levodopa (L-DOPA) + dopa decarboxylase inhibitor treatment in homocysteine formation was evaluated. Finally, we assessed the COMT enzyme expression, activity and cellular localization in the CNS during inflammation-induced neurodegeneration using Western blotting, HPLC and various enzymatic assays. The effects of pharmacological COMT inhibition on neurodegeneration were also studied. The COMT inhibitor entacapone protected against the Ang II-induced perivascular inflammation, renal damage and cardiovascular mortality in dTGRs. COMT inhibitors reduced the albuminuria by 85% and prevented the cardiovascular mortality completely. Entacapone treatment was shown to ameliorate oxidative stress and inflammation. Furthermore, we established that the genetic and pharmacological COMT enzyme blockade protects against the blood pressure-elevating effects of high sodium intake in mice. These effects were mediated via enhanced renal dopaminergic tone and suggest an important role of COMT enzyme, especially in salt-sensitive hypertension. Entacapone also ameliorated the L-DOPA-induced hyperhomocysteinemia in rats. This is important, since decreased homocysteine levels may decrease the risk of cardiovascular diseases in Parkinson´s disease (PD) patients using L-DOPA. The Lipopolysaccharide (LPS)-induced inflammation and subsequent delayed dopaminergic neurodegeneration were accompanied by up-regulation of COMT expression and activity in microglial cells as well as in perivascular cells. Interestingly, similar perivascular up-regulation of COMT expression in inflamed renal tissue was previously noted in dTGRs. These results suggest that inflammation reactions may up-regulate COMT expression. Furthermore, this increased glial and perivascular COMT activity in the central nervous system (CNS) may decrease the bioavailability of L-DOPA and be related to the motor fluctuation noted during L-DOPA therapy in PD patients.

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The central nervous system (CNS) is the most cholesterol-rich organ in the body. Cholesterol is essential to CNS functions such as synaptogenesis and formation of myelin. Significant differences exist in cholesterol metabolism between the CNS and the peripheral organs. However, the regulation of cholesterol metabolism in the CNS is poorly understood compared to our knowledge of the regulation of cholesterol homeostasis in organs reached by cholesterol-carrying lipoprotein particles in the circulation. Defects in CNS cholesterol homeostasis have been linked to a variety of neurodegenerative diseases, including common diseases with complex pathogenetic mechanisms such as Alzheimer s disease. In spite of intense effort, the mechanisms which link disturbed cholesterol homeostasis to these diseases remain elusive. We used three inherited recessive neurodegenerative disorders as models in the studies included in this thesis: Niemann-Pick type C (NPC), infantile neuronal ceroid lipofuscinosis and cathepsin D deficiency. Of these three, NPC has previously been linked to disturbed intracellular cholesterol metabolism. Elucidating the mechanisms with which disturbances of cholesterol homeostasis link to neurodegeneration in recessive inherited disorders with known genetic lesions should shed light on how cholesterol is handled in the healthy CNS and help to understand how these and more complex diseases develop. In the first study we analyzed the synthesis of sterols and the assembly and secretion of lipoprotein particles in Npc1 deficient primary astrocytes. We found that both wild type and Npc1 deficient astrocytes retain significant amounts of desmosterol and other cholesterol precursor sterols as membrane constituents. No difference was observed in the synthesis of sterols and the secretion of newly synthesized sterols between Npc1 wild type, heterozygote or knockout astrocytes. We found that the incorporation of newly synthesized sterols into secreted lipoprotein particles was not inhibited by Npc1 mutation, and the lipoprotein particles were similar to those excreted by wild type astrocytes in shape and size. The bulk of cholesterol was found to be secreted independently of secreted NPC2. These observations demonstrate the ability of Npc1 deficient astrocytes to handle de novo sterols, and highlight the unique sterol composition in the developing brain. Infantile neuronal ceroid lipofuscinosis is caused by the deficiency of a functional Ppt1 enzyme in the cells. In the second study, global gene expression studies of approximately 14000 mouse genes showed significant changes in the expression of 135 genes in Ppt1 deficient neurons compared to wild type. Several genes encoding for enzymes of the mevalonate pathway of cholesterol biosynthesis showed increased expression. As predicted by the expression data, sterol biosynthesis was found to be upregulated in the knockout neurons. These data link Ppt1 deficiency to disturbed cholesterol metabolism in CNS neurons. In the third study we investigated the effect of cathepsin D deficiency on the structure of myelin and lipid homeostasis in the brain. Our proteomics data, immunohistochemistry and western blotting data showed altered levels of the myelin protein components myelin basic protein, proteolipid protein and 2 , 3 -cyclic nucleotide 3 phosphodiesterase in the brains of cathepsin D deficient mice. Electron microscopy revealed altered myelin structure in cathepsin D deficient brains. Additionally, plasmalogen-derived alkenyl chains and 20- and 24-carbon saturated and monounsaturated fatty acids typical for glycosphingolipids were found to be significantly reduced, but polyunsaturated species were significantly increased in the knockout brains, pointing to a decrease in white matter. The levels of ApoE and ABCA1 proteins linked to cholesterol efflux in the CNS were found to be altered in the brains of cathepsin D deficient mice, along with an accumulation of cholesteryl esters and a decrease in triglycerols. Together these data demonstrate altered myelin architecture in cathepsin D deficient mice and link cathepsin D deficiency to aberrant cholesterol metabolism and trafficking. Basic research into rare monogenic diseases sheds light on the underlying biological processes which are perturbed in these conditions and contributes to our understanding of the physiological function of healthy cells. Eventually, understanding gained from the study of disease models may contribute towards establishing treatment for these disorders and further our understanding of the pathogenesis of other, more complex and common diseases.

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Microarrays have a wide range of applications in the biomedical field. From the beginning, arrays have mostly been utilized in cancer research, including classification of tumors into different subgroups and identification of clinical associations. In the microarray format, a collection of small features, such as different oligonucleotides, is attached to a solid support. The advantage of microarray technology is the ability to simultaneously measure changes in the levels of multiple biomolecules. Because many diseases, including cancer, are complex, involving an interplay between various genes and environmental factors, the detection of only a single marker molecule is usually insufficient for determining disease status. Thus, a technique that simultaneously collects information on multiple molecules allows better insights into a complex disease. Since microarrays can be custom-manufactured or obtained from a number of commercial providers, understanding data quality and comparability between different platforms is important to enable the use of the technology to areas beyond basic research. When standardized, integrated array data could ultimately help to offer a complete profile of the disease, illuminating mechanisms and genes behind disorders as well as facilitating disease diagnostics. In the first part of this work, we aimed to elucidate the comparability of gene expression measurements from different oligonucleotide and cDNA microarray platforms. We compared three different gene expression microarrays; one was a commercial oligonucleotide microarray and the others commercial and custom-made cDNA microarrays. The filtered gene expression data from the commercial platforms correlated better across experiments (r=0.78-0.86) than the expression data between the custom-made and either of the two commercial platforms (r=0.62-0.76). Although the results from different platforms correlated reasonably well, combining and comparing the measurements were not straightforward. The clone errors on the custom-made array and annotation and technical differences between the platforms introduced variability in the data. In conclusion, the different gene expression microarray platforms provided results sufficiently concordant for the research setting, but the variability represents a challenge for developing diagnostic applications for the microarrays. In the second part of the work, we performed an integrated high-resolution microarray analysis of gene copy number and expression in 38 laryngeal and oral tongue squamous cell carcinoma cell lines and primary tumors. Our aim was to pinpoint genes for which expression was impacted by changes in copy number. The data revealed that especially amplifications had a clear impact on gene expression. Across the genome, 14-32% of genes in the highly amplified regions (copy number ratio >2.5) had associated overexpression. The impact of decreased copy number on gene underexpression was less clear. Using statistical analysis across the samples, we systematically identified hundreds of genes for which an increased copy number was associated with increased expression. For example, our data implied that FADD and PPFIA1 were frequently overexpressed at the 11q13 amplicon in HNSCC. The 11q13 amplicon, including known oncogenes such as CCND1 and CTTN, is well-characterized in different type of cancers, but the roles of FADD and PPFIA1 remain obscure. Taken together, the integrated microarray analysis revealed a number of known as well as novel target genes in altered regions in HNSCC. The identified genes provide a basis for functional validation and may eventually lead to the identification of novel candidates for targeted therapy in HNSCC.