23 resultados para Open Space

em Helda - Digital Repository of University of Helsinki


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Earlier work has suggested that large-scale dynamos can reach and maintain equipartition field strengths on a dynamical time scale only if magnetic helicity of the fluctuating field can be shed from the domain through open boundaries. To test this scenario in convection-driven dynamos by comparing results for open and closed boundary conditions. Three-dimensional numerical simulations of turbulent compressible convection with shear and rotation are used to study the effects of boundary conditions on the excitation and saturation level of large-scale dynamos. Open (vertical field) and closed (perfect conductor) boundary conditions are used for the magnetic field. The contours of shear are vertical, crossing the outer surface, and are thus ideally suited for driving a shear-induced magnetic helicity flux. We find that for given shear and rotation rate, the growth rate of the magnetic field is larger if open boundary conditions are used. The growth rate first increases for small magnetic Reynolds number, Rm, but then levels off at an approximately constant value for intermediate values of Rm. For large enough Rm, a small-scale dynamo is excited and the growth rate in this regime increases proportional to Rm^(1/2). In the nonlinear regime, the saturation level of the energy of the mean magnetic field is independent of Rm when open boundaries are used. In the case of perfect conductor boundaries, the saturation level first increases as a function of Rm, but then decreases proportional to Rm^(-1) for Rm > 30, indicative of catastrophic quenching. These results suggest that the shear-induced magnetic helicity flux is efficient in alleviating catastrophic quenching when open boundaries are used. The horizontally averaged mean field is still weakly decreasing as a function of Rm even for open boundaries.

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In this thesis, the possibility of extending the Quantization Condition of Dirac for Magnetic Monopoles to noncommutative space-time is investigated. The three publications that this thesis is based on are all in direct link to this investigation. Noncommutative solitons have been found within certain noncommutative field theories, but it is not known whether they possesses only topological charge or also magnetic charge. This is a consequence of that the noncommutative topological charge need not coincide with the noncommutative magnetic charge, although they are equivalent in the commutative context. The aim of this work is to begin to fill this gap of knowledge. The method of investigation is perturbative and leaves open the question of whether a nonperturbative source for the magnetic monopole can be constructed, although some aspects of such a generalization are indicated. The main result is that while the noncommutative Aharonov-Bohm effect can be formulated in a gauge invariant way, the quantization condition of Dirac is not satisfied in the case of a perturbative source for the point-like magnetic monopole.

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Some texts and a performance story. All motivated by the author’s interest in space, in this that surrounds, and that interest, in turn, originating from the author’s earlier studies in cultural anthropology, in observing and experiencing the surrounding animate and inanimate world. The texts in this thesis are alternating between academic and creative writing. They are texts written on a specific site on Suomenlinna island in Helsinki, Finland, as part of the performance ”Beyond the Wind in Front of Me / A Space Ship Journey” story or prologues to that, and the more academic ones supporting them or growing out of them, being accompanied also by the thoughts and practices of others. The main research questions and themes being How to perceive this that surrounds me? What is space, what does it consist of? Is it something that simply surrounds me? Am I a part of it or is it a part of me? How can a space be researched? How to activate a space? What kind of mental images do spaces/places create/uncover/open up in us? How to animate/make alive those images? Body giving meaning to space via actions created by the body. Physical environment contra emotional, imaginary, visionary one. Presence in a space/place. Physical and mental presence. Presence in memories.

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Fluid bed granulation is a key pharmaceutical process which improves many of the powder properties for tablet compression. Dry mixing, wetting and drying phases are included in the fluid bed granulation process. Granules of high quality can be obtained by understanding and controlling the critical process parameters by timely measurements. Physical process measurements and particle size data of a fluid bed granulator that are analysed in an integrated manner are included in process analytical technologies (PAT). Recent regulatory guidelines strongly encourage the pharmaceutical industry to apply scientific and risk management approaches to the development of a product and its manufacturing process. The aim of this study was to utilise PAT tools to increase the process understanding of fluid bed granulation and drying. Inlet air humidity levels and granulation liquid feed affect powder moisture during fluid bed granulation. Moisture influences on many process, granule and tablet qualities. The approach in this thesis was to identify sources of variation that are mainly related to moisture. The aim was to determine correlations and relationships, and utilise the PAT and design space concepts for the fluid bed granulation and drying. Monitoring the material behaviour in a fluidised bed has traditionally relied on the observational ability and experience of an operator. There has been a lack of good criteria for characterising material behaviour during spraying and drying phases, even though the entire performance of a process and end product quality are dependent on it. The granules were produced in an instrumented bench-scale Glatt WSG5 fluid bed granulator. The effect of inlet air humidity and granulation liquid feed on the temperature measurements at different locations of a fluid bed granulator system were determined. This revealed dynamic changes in the measurements and enabled finding the most optimal sites for process control. The moisture originating from the granulation liquid and inlet air affected the temperature of the mass and pressure difference over granules. Moreover, the effects of inlet air humidity and granulation liquid feed rate on granule size were evaluated and compensatory techniques used to optimize particle size. Various end-point indication techniques of drying were compared. The ∆T method, which is based on thermodynamic principles, eliminated the effects of humidity variations and resulted in the most precise estimation of the drying end-point. The influence of fluidisation behaviour on drying end-point detection was determined. The feasibility of the ∆T method and thus the similarities of end-point moisture contents were found to be dependent on the variation in fluidisation between manufacturing batches. A novel parameter that describes behaviour of material in a fluid bed was developed. Flow rate of the process air and turbine fan speed were used to calculate this parameter and it was compared to the fluidisation behaviour and the particle size results. The design space process trajectories for smooth fluidisation based on the fluidisation parameters were determined. With this design space it is possible to avoid excessive fluidisation and improper fluidisation and bed collapse. Furthermore, various process phenomena and failure modes were observed with the in-line particle size analyser. Both rapid increase and a decrease in granule size could be monitored in a timely manner. The fluidisation parameter and the pressure difference over filters were also discovered to express particle size when the granules had been formed. The various physical parameters evaluated in this thesis give valuable information of fluid bed process performance and increase the process understanding.

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Euphrase Kezilahabi on tansanialainen kirjailija, joka ensimmäisenä julkaisi swahilinkielisen vapaalla mitalla kirjoitetun runokokoelman. Perinteisessä swahilirunoudessa tiukat muotosäännöt ovat tärkeitä, ja teos synnytti kiivasta keskustelua. Runoteokset Kichomi ( Viilto , Kipu , 1974) ja Karibu Ndani ( Tervetuloa sisään , 1988) sekä Kezilahabin muu tuotanto voidaan nähdä uuden sukupolven taiteena. Kezilahabi on arvostettu runoilija, mutta hänen runojaan ei aiemmin ole käännetty englanniksi (yksittäisiä säkeitä lukuunottamatta), eikä juurikaan tutkittu yksityiskohtaisesti. Yleiskuvaan pyrkivissä lausunnoissa Kezilahabin runouden on hyvin usein määritelty olevan poliittista. Monet Kezilahabin runoista ottavatkin kantaa yhteiskunnallisiin kysymyksiin, mutta niiden pohdinta on kuitenkin runoissa vain yksi taso. Sen lisäksi Kezilahabin lyriikassa on paljon muuta ennen kartoittamatonta tämä tutkimus keskittyy veden kuvaan (the image of water). Kezilahabi vietti lapsuutensa saarella Victoria-järven keskellä, ja hänen vesikuvastonsa on rikasta. Tutkimuskysymyksenä on, mitä veden kuva runoteoksissa Kichomi ja Karibu Ndani esittää. Runojen analysoinnissa ja tulkinnassa on tarkasteltu myös sitä, miten äänteellinen taso osallistuu kuvien luomiseen. Tutkimuksen määritelmä kuvasta pohjautuu osittain Hugh Kennerin näkemykseen, jonka mukaan oleellista kuvassa on kirjaimellinen taso. Kennerin lähtökohtaan on yhdistetty John Shoptawin teoriaa, joka korostaa runon äänteellisen puolen tärkeyttä merkityksen muodostumisessa. Foneemien analyysissä vaikutteena on ollut Reuven Tsurin teoria. Analyysiosio osoittaa, että veden kuva edustaa ja käsittelee teoksissa lukuisia teemoja: elämää, kuolemaa, fyysistä vetovoimaa, runoutta, mielikuvitusta ja (ali)tajuntaa sekä moraalia. Veden kuvan tutkimuksen pohjalta on nähtävissä, että Kezilahabin filosofia asettuu elävä/kuollut- ja elämä/kuolema dikotomioiden ulkopuolelle.

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Space in musical semiosis is a study of musical meaning, spatiality and composition. Earlier studies on musical composition have not adequately treated the problems of musical signification. Here, composition is considered an epitomic process of musical signification. Hence the core problems of composition theory are core problems of musical semiotics. The study employs a framework of naturalist pragmatism, based on C. S. Peirce’s philosophy. It operates on concepts such as subject, experience, mind and inquiry, and incorporates relevant ideas of Aristotle, Peirce and John Dewey into a synthetic view of esthetic, practic, and semiotic for the benefit of grasping musical signification process as a case of semiosis in general. Based on expert accounts, music is depicted as real, communicative, representational, useful, embodied and non-arbitrary. These describe how music and the musical composition process are mental processes. Peirce’s theories are combined with current morphological theories of cognition into a view of mind, in which space is central. This requires an analysis of space, and the acceptance of a relativist understanding of spatiality. This approach to signification suggests that mental processes are spatially embodied, by virtue of hard facts of the world, literal representations of objects, as well as primary and complex metaphors each sharing identities of spatial structures. Consequently, music and the musical composition process are spatially embodied. Composing music appears as a process of constructing metaphors—as a praxis of shaping and reshaping features of sound, representable from simple quality dimensions to complex domains. In principle, any conceptual space, metaphorical or literal, may set off and steer elaboration, depending on the practical bearings on the habits of feeling, thinking and action, induced in musical communication. In this sense, it is evident that music helps us to reorganize our habits of feeling, thinking, and action. These habits, in turn, constitute our existence. The combination of Peirce and morphological approaches to cognition serves well for understanding musical and general signification. It appears both possible and worthwhile to address a variety of issues central to musicological inquiry in the framework of naturalist pragmatism. The study may also contribute to the development of Peircean semiotics.

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My thesis concerns the notion of existence as an encounter, as developed in the philosophy of Gilles Deleuze (1925 1995). What this denotes is a critical stance towards a major current in Western philosophical tradition which Deleuze nominates as representational thinking. Such thinking strives to provide a stable ground for identities by appealing to transcendent structures behind the apparent reality and explaining the manifest diversity of the given by such notions as essence, idea, God, or totality of the world. In contrast to this, Deleuze states that abstractions such as these do not explain anything, but rather that they need to be explained. Yet, Deleuze does not appeal merely to the given. He sees that one must posit a genetic element that accounts for experience, and this element must not be naïvely traced from the empirical. Deleuze nominates his philosophy as transcendental empiricism and he seeks to bring together the approaches of both empiricism and transcendental philosophy. In chapter one I look into the motivations of Deleuze s transcendental empiricism and analyse it as an encounter between Deleuze s readings of David Hume and Immanuel Kant. This encounter regards, first of all, the question of subjectivity and results in a conception of identity as non-essential process. A pre-given concept of identity does not explain the nature of things, but the concept itself must be explained. From this point of view, the process of individualisation must become the central concern. In chapter two I discuss Deleuze s concept of the affect as the basis of identity and his affiliation with the theories of Gilbert Simondon and Jakob von Uexküll. From this basis develops a morphogenetic theory of individuation-as-process. In analysing such a process of individuation, the modal category of the virtual becomes of great value, being an open, indeterminate charge of potentiality. As the virtual concerns becoming or the continuous process of actualisation, then time, rather than space, will be the privileged field of consideration. Chapter three is devoted to the discussion of the temporal aspect of the virtual and difference-without-identity. The essentially temporal process of subjectification results in a conception of the subject as composition: an assemblage of heterogeneous elements. Therefore art and aesthetic experience is valued by Deleuze because they disclose the construct-like nature of subjectivity in the sensations they produce. Through the domain of the aesthetic the subject is immersed in the network of affectivity that is the material diversity of the world. Chapter four addresses a phenomenon displaying this diversified indentity: the simulacrum an identity that is not grounded in an essence. Developed on the basis of the simulacrum, a theory of identity as assemblage emerges in chapter five. As the problematic of simulacra concerns perhaps foremost the artistic presentation, I shall look into the identity of a work of art as assemblage. To take an example of a concrete artistic practice and to remain within the problematic of the simulacrum, I shall finally address the question of reproduction particularly in the case recorded music and its identity regarding the work of art. In conclusion, I propose that by overturning its initial representational schema, phonographic music addresses its own medium and turns it into an inscription of difference, exposing the listener to an encounter with the virtual.

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The PhD dissertation "Bucking Glances: On Body, Gender, Sexuality and Visual Culture Research" consists of theoretical introduction and five articles published between 2002-2005. The articles analyze the position of visual representations in the processes of knowledge production on acceptable genders, bodies, and sexualities in contemporary Wes¬tern societies. The research material is heterogeneous, consisting of representations of contemporary art, advertisements, and fashion images. The ideological starting point of the PhD dissertation is the politics of the gaze and the methods used to expose this are the concepts of oppositional gaze, close reading, and resisting reading. The study situates visual representations in dialogue with the concepts of the grotesque and androgyny, as well as with queer-theory and theories of the gaze. The research challenges normative meanings of visual representations and opens up space for more non-conventional readings attached to femininity and masculinity. The visual material is read as troubling the prevailing heteronormative gender system. The dissertation also indicates how visual culture research utilizing the approach of queer theory can be fruitful in opposing and re-visioning changes in the repressive gender system. The article "A Heroic Male and A Beautiful Woman. Teemu Mäki, Orlan and the Ambivalence of the Grotesque Body" problematizes the concept of heroic masculinity through the analysis of the Finnish artist Teemu Mäki's masochistic performance The Good Friday (1989). It also analyzes cosmetic surgery, undertaken by the French artist Orlan, as a cultural tool in constructing and visualizing the contemporary, com¬mercial ideals of female beauty. The article "Boys Will Be Girls Will Be Boys Will Be Girls. The Ambivalence of Androgyny in Calvin Klein' Advertisements" is a close reading of the Calvin Klein perfume advertisement One (1998) in reference to the concept of androgyny. The critical point of the article is that androgynous male bodies allow the extension of the categorical boundaries of masculinity and homosexuality, whereas representations of androgynous women feed into the prevailing stereotypes of femininity, namely the fear of fat. The article "See-through Closet: Female Androgyny in the 1990s Fashion Images, New Woman and Lesbian Chic" analyzes the late 1990s fashion advertisements through the concept of female androgyny. The article argues that the figures of the masculine female androgynes in the late 1990s fashion magazines do not problematize the dichotomous gender binary. The women do not pass as men but produce a variation of heterosexual desirability. At the same time, the representations open up space for lesbian gazing and desiring. The article "Why are there no lesbian advertisements?" addresses the issue of femme gaze and desire in relation to heterosexual fashion advertisements from the British edition of the mainstream fashion magazine Vogue. The article considers possibilities for resistant femme visibility, identification, and desire. The article "Woman, Food, Home. Pirjetta Brander's and Heidi Romo's Works as Bucking Representations of Femininity" analyses the production and queering of heteronormative femininity and family through the analysis of art works. The article discusses how the term queer has been translated into Finnish. The article also introduces a new translation for the term queer: the noun vikuuri, i.e. faulty form and the verb vikuroida, i.e. to buck. In Finnish, the term vikuuri is the vernacular or broken form of the term figure, i.e. figuuri. Vikuuri represents all forms situated outside the norm and the normative.

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Talking about symptoms during medical consultation. A conversation analytical study of doctors questions This linguistically oriented conversation analytic study investigates doctors questions and patients answers during medical consultation. The focus is on 1) the syntactic constructions of the doctors questions concerning the patients symptoms, 2) the function of different types of syntactic constructions, and 3) the sequential placement of the questions. The data used in the study consist of 57 videotaped doctor patient encounters in Finnish primary health care. The study shows that the traditional division between open and closed questions is vague and needs to be examined further. Open wh-questions and closed yes/no questions form heterogeneous classes: some of the closed questions can be treated as open and vice versa. Wh-questions which occur during the physical examination are often constructed to elicit short answers. These questions can consist of one word (e.g. milloin when ) which does not move to a new topic but supports the unfinished activity of palpation. During the verbal examination, wh-questions are formulated to elicit long descriptions as answers. For example, by asking mites + X ( what about + X), the doctor can open up a new topic and simultaneously give the patient the opportunity to discuss the topic from his/her perspective. Almost half of the yes/no questions project longer than just a minimal answer (e.g. a short confirmation or rejection). In these questions, the doctors use verbal elements which show that more than just a minimal answer is required. They can, for example, add an indefinite element (joku some or mitään any ) to a yes/no question, add a conjunctive vai ( or ) to the end of the question and thus open a space for various types of answers, or add a suggested answer to the question. In addition, the results show that declarative questions not only check understanding, but display the doctor s diagnosing process, check whether the doctor can move on to the next topic or action, and display implicitly the doctor s idea of what is connected and what is relevant. One aim of the study is to describe how different syntactic structures work together. A typical question chain consists of two or three questions. The first question is an open wh-question that elicits a new topic and creates different types of presuppositions. Contingent questions are constructed as yes/no questions that seek an affirmative answer or as declarative sentences that seek confirmation. Contingent questions can function as repair initiators and thus support achieving mutual understanding. Therefore, they are tools for the doctor to construct a description of the medical problem collaboratively with the patient. The results add to the results of previous studies on questions in medical consultation, but also suggest some corrections. They provide additional evidence for the idea that different types of syntactic constructions are useful in different types of settings. However, they also show that the variety of questions that doctors use is more manifold and diverse than the variety introduced in earlier studies and textbooks.

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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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This is an ethnographic case study of the creation and emergence of a playworld – a pedagogical approach aimed at promoting children’s development and learning in early education settings through the use of play and drama. The data was collected in a Finnish experimental mixed-age elementary school classroom in the school year 2003-2004. In the playworld students and teachers explore different social and cultural phenomena through taking on the roles of characters from a story or a piece of literature and acting inside the frames of an improvised plot. The thesis takes under scrutiny the notion of agency in education. It produces theoretically grounded empirical knowledge of the ways in which children struggle to become recognized and agentive actors in early education settings and how their agency develops in their interaction with adults. The study builds on the activity theoretical and sociocultural tradition and develops a methodological framework called video-based narrative interaction analysis for studying student agency as developing over time but manifesting through the situational material and discursive local interactions. The research questions are: 1. What are the children’s ways of enacting their agency in the playworld? 2. How do the children’s agentive actions change and develop over the spring? 3. What are the potentials and challenges of the playworld for promoting student agency? 4. How do the teachers and the children deal with the contradiction between control and agency in the playworld? The study consists of a summary part and four empirical articles which each have a particular viewpoint. Articles I and II deal with individual students’ paths to agency. In Article I the focus is on the role of resistance and questioning in enabling important spaces for agency. Article II takes a critical gender perspective and analyzes how two girls struggled towards recognition in the playworld. It also illuminates the role of imagination in developing a sense of agency. Article III examines how the open-ended and improvisational nature of the playworld interaction provided experiences and a sense of ‘shared agency’ for the students and teachers in the class. Article IV turns the focus on the teachers and analyzes how their role actions in the playworld helped the children to enact agency. It also discusses the challenges that the teachers faced in this work and asks what makes the playworld activity sustainable in the class. The summary part provides a critical literature review on the concept of agency and argues that the inherently contradictory nature of the phenomenon of agency has not been sufficiently theorized. The summary part also locates the playworld intervention in a historical frame by discussing the changing conceptions of adulthood and childhood in the West. By focusing on the changing role of play and art in both adults’ and children’s contemporary lives, the thesis opens up an important but often neglected perspective on the problem of promoting student agency in education. The results illustrate how engaging in a collectively imagined and dramatized pretend play space together with the children enabled the teachers to momentarily put aside their “knower” positions in the classroom. The fictive roles and the narrative plot helped them to create a necessary incompleteness and open-endedness in the activity that stimulated the children’s initiatives. This meant that the children too could momentarily step out of their traditional classroom positions as pupils and initiate action to further the collective play. Engaging in this kind of unconventional activity and taking up and enacting agency was, however, very challenging for the participating children and teachers. It often contradicted the need to sustain control and order in the classroom. The study concludes that play- and drama-based pedagogies offer a unique but undeveloped potential for developing educational spaces that help teachers and children deal with the often contradictory requirements of schooling.

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Mitochondria have evolved from endosymbiotic alpha-proteobacteria. During the endosymbiotic process early eukaryotes dumped the major component of the bacterial cell wall, the peptidoglycan layer. Peptidoglycan is synthesized and maintained by active-site serine enzymes belonging to the penicillin-binding protein and the β-lactamase superfamily. Mammals harbor a protein named LACTB that shares sequence similarity with bacterial penicillin-binding proteins and β-lactamases. Since eukaryotes lack the synthesis machinery for peptidoglycan, the physiological role of LACTB is intriguing. Recently, LACTB has been validated in vivo to be causative for obesity, suggesting that LACTB is implicated in metabolic processes. The aim of this study was to investigate the phylogeny, structure, biochemistry and cell biology of LACTB in order to elucidate its physiological function. Phylogenetic analysis revealed that LACTB has evolved from penicillin binding-proteins present in the bacterial periplasmic space. A structural model of LACTB indicates that LACTB shares characteristic features common to all penicillin-binding proteins and β-lactamases. Recombinat LACTB protein expressed in E. coli was recovered in significant quantities. Biochemical and cell biology studies showed that LACTB is a soluble protein localized in the mitochondrial intermembrane space. Further analysis showed that LACTB preprotein underwent proteolytic processing disclosing an N-terminal tetrapeptide motif also found in a set of cell death-inducing proteins. Electron microscopy structural studies revealed that LACTB can polymerize to form stable filaments with lengths ranging from twenty to several hundred nanometers. These data suggest that LACTB filaments define a distinct microdomain in the intermembrane space. A possible role of LACTB filaments is proposed in the intramitochondrial membrane organization and microcompartmentation. The implications of these findings offer novel insight into the evolution of mitochondria. Further studies of the LACTB function might provide a tool to treat mitochondria-related metabolic diseases.

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Glaucoma is the second leading cause of blindness worldwide. It is a group of optic neuropathies, characterized by progressive optic nerve degeneration, excavation of the optic disc due to apoptosis of retinal ganglion cells and corresponding visual field defects. Open angle glaucoma (OAG) is a subtype of glaucoma, classified according to the age of onset into juvenile and adult- forms with a cut-off point of 40 years of age. The prevalence of OAG is 1-2% of the population over 40 years and increases with age. During the last decade several candidate loci and three candidate genes, myocilin (MYOC), optineurin (OPTN) and WD40-repeat 36 (WDR36), for OAG have been identified. Exfoliation syndrome (XFS), age, elevated intraocular pressure and genetic predisposition are known risk factors for OAG. XFS is characterized by accumulation of grayish scales of fibrillogranular extracellular material in the anterior segment of the eye. XFS is overall the most common identifiable cause of glaucoma (exfoliation glaucoma, XFG). In the past year, three single nucleotide polymorphisms (SNPs) on the lysyl oxidase like 1 (LOXL1) gene have been associated with XFS and XFG in several populations. This thesis describes the first molecular genetic studies of OAG and XFS/XFG in the Finnish population. The role of the MYOC and OPTN genes and fourteen candidate loci was investigated in eight Finnish glaucoma families. Both candidate genes and loci were excluded in families, further confirming the heterogeneous nature of OAG. To investigate the genetic basis of glaucoma in a large Finnish family with juvenile and adult onset OAG, we analysed the MYOC gene in family members. Glaucoma associated mutation (Thr377Met) was identified in the MYOC gene segregating with the disease in the family. This finding has great significance for the family and encourages investigating the MYOC gene also in other Finnish OAG families. In order to identify the genetic susceptibility loci for XFS, we carried out a genome-wide scan in the extended Finnish XFS family. This scan produced promising candidate locus on chromosomal region 18q12.1-21.33 and several additional putative susceptibility loci for XFS. This locus on chromosome 18 provides a solid starting point for the fine-scale mapping studies, which are needed to identify variants conferring susceptibility to XFS in the region. A case-control and family-based association study and family-based linkage study was performed to evaluate whether SNPs in the LOXL1 gene contain a risk for XFS, XFG or POAG in the Finnish patients. A significant association between the LOXL1 gene SNPs and XFS and XFG was confirmed in the Finnish population. However, no association was detected with POAG. Probably also other genetic and environmental factors are involved in the pathogenesis of XFS and XFG.

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Being at the crossroads of the Old World continents, Western Asia has a unique position through which the dispersal and migration of mammals and the interaction of faunal bioprovinces occurred. Despite its critical position, the record of Miocene mammals in Western Asia is sporadic and there are large spatial and temporal gaps between the known fossil localities. Although the development of the mammalian faunas in the Miocene of the Old World is well known and there is ample evidence for environmental shifts in this epoch, efforts toward quantification of habitat changes and development of chronofaunas based on faunal compositions were mostly neglected. Advancement of chronological, paleoclimatological, and paleogeographical reconstruction tools and techniques and increased numbers of new discoveries in recent decades have brought the need for updating and modification of our level of understanding. We under took fieldwork and systematic study of mammalian trace and body fossils from the northwestern parts of Iran along with analysis of large mammal data from the NOW database. The data analysis was used to study the provinciality, relative abundance, and distribution history of the closed- and open-adapted taxa and chronofaunas in the Miocene of the Old World and Western Asia. The provinciality analysis was carried out, using locality clustering, and the relative abundance of the closed- and open-adapted taxa was surveyed at the family level. The distribution history of the chronofaunas was studied, using faunal resemblance indices and new mapping techniques, together with humidity analysis based on mean ordinated hypsodonty. Paleoichnological studies revealed the abundance of mammalian footprints in several parts of the basins studied, which are normally not fossiliferous in terms of body fossils. The systematic study and biochronology of the newly discovered mammalian fossils in northwestern Iran indicates their close affinities with middle Turolian faunas. Large cranial remains of hipparionine horses, previously unknown in Iran and Western Asia, are among the material studied. The initiation of a new field project in the famous Maragheh locality also brings new opportunities to address questions regarding the chronology and paleoenvironment of this classical site. Provinciality analysis modified our previous level of understandings, indicating the interaction of four provinces in Western Asia. The development of these provinces was apparently due to the presence of high mountain ranges in the area, which affected the dispersal of mammals and also climatic patterns. Higher temperatures and possibly higher co2 levels in the Middle Miocene Climatic Optimum apparently favored the development of the closed forested environments that supported the dominance of the closed-adapted taxa. The increased seasonality and the progressive cooling and drying of the midlatitudes toward the Late Miocene maintained the dominance of open-adapted faunas. It appears that the late Middle Miocene was the time of transition from a more forested to a less forested world. The distribution history of the closed- and open-adapted chronofaunas shows the presence of cosmopolitan and endemic faunas in Western Asia. The closed-adapted faunas, such as the Arabian chronofauna of the late Early‒early Middle Miocene, demonstrated a rapid buildup and gradual decline. The open-adapted chronofaunas, such as the Late Miocene Maraghean fauna, climaxed gradually by filling the opening environments and moving in response to changes in humidity patterns. They abruptly declined due to demise of their favored environments. The Siwalikan chronofauna of the early Late Miocene remained endemic and restricted through all its history. This study highlights the importance of field investigations and indicates that new surveys in the vast areas of Western Asia, which are poorly sampled in terms of fossil mammal localities, can still be promising. Clustering of the localities supports the consistency of formerly known patterns and augments them. Although the quantitative approach to relative abundance history of the closed- and open-adapted mammals harks back to more than half a century ago, it is a novel technique providing robust results. Tracking the history of the chronofaunas in space and time by means of new computational and illustration methods is also a new practice that can be expanded to new areas and time spans.