39 resultados para highly siderophile elements

em Helda - Digital Repository of University of Helsinki


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Volatility is central in options pricing and risk management. It reflects the uncertainty of investors and the inherent instability of the economy. Time series methods are among the most widely applied scientific methods to analyze and predict volatility. Very frequently sampled data contain much valuable information about the different elements of volatility and may ultimately reveal the reasons for time varying volatility. The use of such ultra-high-frequency data is common to all three essays of the dissertation. The dissertation belongs to the field of financial econometrics. The first essay uses wavelet methods to study the time-varying behavior of scaling laws and long-memory in the five-minute volatility series of Nokia on the Helsinki Stock Exchange around the burst of the IT-bubble. The essay is motivated by earlier findings which suggest that different scaling laws may apply to intraday time-scales and to larger time-scales, implying that the so-called annualized volatility depends on the data sampling frequency. The empirical results confirm the appearance of time varying long-memory and different scaling laws that, for a significant part, can be attributed to investor irrationality and to an intraday volatility periodicity called the New York effect. The findings have potentially important consequences for options pricing and risk management that commonly assume constant memory and scaling. The second essay investigates modelling the duration between trades in stock markets. Durations convoy information about investor intentions and provide an alternative view at volatility. Generalizations of standard autoregressive conditional duration (ACD) models are developed to meet needs observed in previous applications of the standard models. According to the empirical results based on data of actively traded stocks on the New York Stock Exchange and the Helsinki Stock Exchange the proposed generalization clearly outperforms the standard models and also performs well in comparison to another recently proposed alternative to the standard models. The distribution used to derive the generalization may also prove valuable in other areas of risk management. The third essay studies empirically the effect of decimalization on volatility and market microstructure noise. Decimalization refers to the change from fractional pricing to decimal pricing and it was carried out on the New York Stock Exchange in January, 2001. The methods used here are more accurate than in the earlier studies and put more weight on market microstructure. The main result is that decimalization decreased observed volatility by reducing noise variance especially for the highly active stocks. The results help risk management and market mechanism designing.

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This thesis is a comparative case study in Japanese video game localization for the video games Sairen, Sairen 2 and Sairen Nyûtoransurêshon, and English-language localized versions of the same games as published in Scandinavia and Australia/New Zealand. All games are developed by Sony Computer Entertainment Inc. and published exclusively for Playstation2 and Playstation3 consoles. The fictional world of the Sairen games draws much influence from Japanese history, as well as from popular and contemporary culture, and in doing so caters mainly to a Japanese audience. For localization, i.e. the adaptation of a product to make it accessible to users outside the original market it was intended for in the first place, this is a challenging issue. Video games are media of entertainment, and therefore localization practice must preserve the games’ effects on the players’ emotions. Further, video games are digital products that are comprised of a multitude of distinct elements, some of which are part of the game world, while others regulate the connection between the player as part of the real world and the game as digital medium. As a result, video game localization is also a practice that has to cope with the technical restrictions that are inherent to the medium. The main theory used throughout the thesis is Anthony Pym’s framework for localization studies that considers the user of the localized product as a defining part of the localization process. This concept presupposes that localization is an adaptation that is performed to make a product better suited for use during a specific reception situation. Pym also addresses the factor that certain products may resist distribution into certain reception situations because of their content, and that certain aspects of localization aim to reduce this resistance through significant alterations of the original product. While Pym developed his ideas with mainly regular software in mind, they can also be adapted well to study video games from a localization angle. Since modern video games are highly complex entities that often switch between interactive and non-interactive modes, Pym’s ideas are adapted throughout the thesis to suit the particular elements being studied. Instances analyzed in this thesis include menu screens, video clips, in-game action and websites. The main research questions focus on how the games’ rules influence localization, and how the games’ fictional domain influences localization. Because there are so many peculiarities inherent to the medium of the video game, other theories are introduced as well to complement the research at hand. These include Lawrence Venuti’s discussions of foreiginizing and domesticating translation methods for literary translation, and Jesper Juul’s definition of games. Additionally, knowledge gathered from interviews with video game localization professionals in Japan during September and October 2009 is also utilized for this study. Apart from answering the aforementioned research questions, one of this thesis’ aims is to enrich the still rather small field of game localization studies, and the study of Japanese video games in particular, one of Japan’s most successful cultural exports.

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The subject of my research is the romantic dating culture, the practice of 'going with', among preadolescents ('tweens') in Finland during the 1990s. Preadolescence is a cultural construction of the post-industrial period, experienced by school students between the ages of 7 to 13. Deemed by researchers as a shallow, unchallenging and uninteresting period, it has been shadowed in previous studies by early childhood and puberty. This study combines paradigms of the folkloristic research of children's lore, which began in the 1970s, with those of later, turn-of-the-century girls study. The phenomena of romantic girl culture are studied in several ways, through ample and varied subject materials collected in different places at different times. The research material was collected directly from schoolchildren through interviews, questionnaires and the observations of preadolescents' behavior in discos, among other methods. Part of the material consists of reminiscent thematic writings and parts have been quoted from tween message boards. A general picture of romantic preadolescent dating culture is formed in this study from five previously published articles and a summary. The influence of western culture, with its respect for relationships, is evident in tween dating culture. Seven- to thirteen-year olds use the elements of the society around them to construct an appropriate way for themselves to 'go out' with someone. Many expressions in preadolescent dating culture are contrary to the models of adult relationships. For example, a couple isn't necessarily expected to meet each other even once, or the other party, the boy, doesn't even need to know he's dating someone. Girls organize and experience relationships by playing card fortune-telling, calculating 'Love Percentages', and other methods. Categorizing tween dating culture and its related emotional qualities from an adult point of view as simply a play is one example of the hierarchical system of generations where childhood emotions, actions and conceptions of reality aren't valued as highly as the 'real life' of adults. Lowest on the totem pole are little girls, who in this study get their voices backed up by the researcher's adulthood and research-based sisterhood. Keywords: childhood, children's lore, dating culture, girls and boys, girls study, fortune-telling games, preadolescence/tweens

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This study concentrates on the contested concept of pastiche in literary studies. It offers the first detailed examination of the history of the concept from its origins in the seventeenth century to the present, showing how pastiche emerged as a critical concept in interaction with the emerging conception of authorial originality and the copyright laws protecting it. One of the key results of this investigation is the contextualisation of the postmodern debate on pastiche. Even though postmodern critics often emphasise the radical novelty of pastiche, they in fact resuscitate older positions and arguments without necessarily reflecting on their historical conditions. This historical background is then used to analyse the distinction between the primarily French conception of pastiche as the imitation of style and the postmodern notion of it as the compilation of different elements. The latter s vagueness and inclusiveness detracts from its value as a critical concept. The study thus concentrates on the notion of stylistic pastiche, challenging the widespread prejudice that it is merely an indication of lack of talent. Because it is multiply based on repetition, pastiche is in fact a highly ambiguous or double-edged practice that calls into question the distinction between repetition and original, thereby undermining the received notion of individual unique authorship as a fundamental aesthetic value. Pastiche does not, however, constitute a radical upheaval of the basic assumptions on which the present institution of literature relies, since, in order to mark its difference, pastiche always refers to a source outside itself against which its difference is measured. Finally, the theoretical analysis of pastiche is applied to literary works. The pastiches written by Marcel Proust demonstrate how it can become an integral part of a writer s poetics: imitation of style is shown to provide Proust with a way of exploring the role of style as a connecting point between inner vision and reality. The pastiches of the Sherlock Holmes stories by Michael Dibdin, Nicholas Meyer and the duo Adrian Conan Doyle and John Dickson Carr illustrate the functions of pastiche within a genre detective fiction that is itself fundamentally repetitive. A.S. Byatt s Possession and D.M. Thomas s Charlotte use Victorian pastiches to investigate the conditions of literary creation in the age of postmodern suspicion of creativity and individuality. The study thus argues that the concept of pastiche has valuable insights to offer to literary criticism and theory, and that literary pastiches, though often dismissed in reviews and criticism, are a particularly interesting object of study precisely because of their characteristic ambiguity.

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"Infinitive and its infinity" advocates an approach to infinitives that differs from most previous descriptions in several ways. Infinitives are generally considered to be an illustrative example of an inherently subordinated verb category. This is due to the fact that they are morphologically reduced and are allegedly not able to function as the only predicate of an independent clause. While former descriptions have thus treated infinitives as a linguistic category heavily dependent on the finite verb, my claim is that Finnish A-infinitives (e.g. juosta to run , olla to be ) can be used as independent grammatical units: they need not be either dependent or subordinated, but can have an equal status with finite constructions. In other words, they can be conceptually and interactionally non-dependent. Theoretically, the main objective of the thesis is to discover the nature of non-finite conceptualization and the ways in which it is utilized in everyday interactions. This is accomplished by contrasting finite and non-finite conceptualization with respect to the morphosyntactic marking of person, tense and modality. I argue that the morphologically reduced nature of infinitives can be used as an interactional resource. Independent A-infinitive constructions designate verbal processes that profile no participants, lack any connection with time, and present states of affairs as intensional, structural spaces. Consequently, they provide the interactants with a conceptual alternative in contrast to finite predications that are in Finnish always grammatically anchored to time, modality and person. The deictically unanchored character of A-infinitive constructions makes them highly affective and reflexive in nature. I discuss my findings primarily in the light of Cognitive Grammar. I have drawn insight from various other fields, too: among the theories that are touched upon are interactional linguistics, functional-typological linguistics, and studies on the poetic and metapragmatic use of language. The study is based on empirical data interpreted in qualitative terms. Analyses are based on 980 examples coming mainly from written language. Some 20 examples of spoken data are analyzed as well. In sum, the thesis presents a critical statement towards the finite-verb centred outlook on language and shows that analyzing non-finite elements as such reveals new aspects of grammar and interaction. This is to acknowledge the fact that infinitives, albeit prototypically participating in the coding of dependent events, can also be used outside of the context of the finite verb. Such a view poses several new research questions, as a linguistic category generally seen to code dependent, less prominent states of affairs , now is viewed on as possessing a full cognitive and pragmatic potential.

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The neural basis of visual perception can be understood only when the sequence of cortical activity underlying successful recognition is known. The early steps in this processing chain, from retina to the primary visual cortex, are highly local, and the perception of more complex shapes requires integration of the local information. In Study I of this thesis, the progression from local to global visual analysis was assessed by recording cortical magnetoencephalographic (MEG) responses to arrays of elements that either did or did not form global contours. The results demonstrated two spatially and temporally distinct stages of processing: The first, emerging 70 ms after stimulus onset around the calcarine sulcus, was sensitive to local features only, whereas the second, starting at 130 ms across the occipital and posterior parietal cortices, reflected the global configuration. To explore the links between cortical activity and visual recognition, Studies II III presented subjects with recognition tasks of varying levels of difficulty. The occipito-temporal responses from 150 ms onwards were closely linked to recognition performance, in contrast to the 100-ms mid-occipital responses. The averaged responses increased gradually as a function of recognition performance, and further analysis (Study III) showed the single response strengths to be graded as well. Study IV addressed the attention dependence of the different processing stages: Occipito-temporal responses peaking around 150 ms depended on the content of the visual field (faces vs. houses), whereas the later and more sustained activity was strongly modulated by the observers attention. Hemodynamic responses paralleled the pattern of the more sustained electrophysiological responses. Study V assessed the temporal processing capacity of the human object recognition system. Above sufficient luminance, contrast and size of the object, the processing speed was not limited by such low-level factors. Taken together, these studies demonstrate several distinct stages in the cortical activation sequence underlying the object recognition chain, reflecting the level of feature integration, difficulty of recognition, and direction of attention.

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Failures in industrial organizations dealing with hazardous technologies can have widespread consequences for the safety of the workers and the general population. Psychology can have a major role in contributing to the safe and reliable operation of these technologies. Most current models of safety management in complex sociotechnical systems such as nuclear power plant maintenance are either non-contextual or based on an overly-rational image of an organization. Thus, they fail to grasp either the actual requirements of the work or the socially-constructed nature of the work in question. The general aim of the present study is to develop and test a methodology for contextual assessment of organizational culture in complex sociotechnical systems. This is done by demonstrating the findings that the application of the emerging methodology produces in the domain of maintenance of a nuclear power plant (NPP). The concepts of organizational culture and organizational core task (OCT) are operationalized and tested in the case studies. We argue that when the complexity of the work, technology and social environment is increased, the significance of the most implicit features of organizational culture as a means of coordinating the work and achieving safety and effectiveness of the activities also increases. For this reason a cultural perspective could provide additional insight into the problem of safety management. The present study aims to determine; (1) the elements of the organizational culture in complex sociotechnical systems; (2) the demands the maintenance task sets for the organizational culture; (3) how the current organizational culture at the case organizations supports the perception and fulfilment of the demands of the maintenance work; (4) the similarities and differences between the maintenance cultures at the case organizations, and (5) the necessary assessment of the organizational culture in complex sociotechnical systems. Three in-depth case studies were carried out at the maintenance units of three Nordic NPPs. The case studies employed an iterative and multimethod research strategy. The following methods were used: interviews, CULTURE-survey, seminars, document analysis and group work. Both cultural analysis and task modelling were carried out. The results indicate that organizational culture in complex sociotechnical systems can be characterised according to three qualitatively different elements: structure, internal integration and conceptions. All three of these elements of culture as well as their interrelations have to be considered in organizational assessments or important aspects of the organizational dynamics will be overlooked. On the basis of OCT modelling, the maintenance core task was defined as balancing between three critical demands: anticipating the condition of the plant and conducting preventive maintenance accordingly, reacting to unexpected technical faults and monitoring and reflecting on the effects of maintenance actions and the condition of the plant. The results indicate that safety was highly valued at all three plants, and in that sense they all had strong safety cultures. In other respects the cultural features were quite different, and thus the culturally-accepted means of maintaining high safety also differed. The handicraft nature of maintenance work was emphasised as a source of identity at the NPPs. Overall, the importance of safety was taken for granted, but the cultural norms concerning the appropriate means to guarantee it were little reflected. A sense of control, personal responsibility and organizational changes emerged as challenging issues at all the plants. The study shows that in complex sociotechnical systems it is both necessary and possible to analyse the safety and effectiveness of the organizational culture. Safety in complex sociotechnical systems cannot be understood or managed without understanding the demands of the organizational core task and managing the dynamics between the three elements of the organizational culture.

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The androgen receptor (AR) mediates the effects of the male sex-steroid hormones (androgens), testosterone and 5?-dihydrotestosterone. Androgens are critical in the development and maintenance of male sexual characteristics. AR is a member of the steroid receptor ligand-inducible transcription factor family. The steroid receptor family is a subgroup of the nuclear receptor superfamily that also includes receptors for the active forms of vitamin A, vitamin D3, and thyroid hormones. Like all nuclear receptors, AR has a conserved modular structure consisting of a non-conserved amino-terminal domain (NTD), containing the intrinsic activation function 1, a highly conserved DNA-binding domain, and a conserved ligand-binding domain (LBD) that harbors the activation function 2. Each of these domains plays an important role in receptor function and signaling, either via intra- and inter-receptor interactions, interactions with specific DNA sequences, termed hormone response elements, or via functional interactions with domain-specific proteins, termed coregulators (coactivators and corepressors). Upon binding androgens, AR acquires a new conformational state, translocates to the nucleus, binds to androgen response elements, homodimerizes and recruits sequence-specific coregulatory factors and the basal transcription machinery. This set of events is required to activate gene transcription (expression). Gene transcription is a strictly modulated process that governs cell growth, cell homeostasis, cell function and cell death. Disruptions of AR transcriptional activity caused by receptor mutations and/or altered coregulator interactions are linked to a wide spectrum of androgen insensitivity syndromes, and to the pathogenesis of prostate cancer (CaP). The treatment of CaP usually involves androgen depletion therapy (ADT). ADT achieves significant clinical responses during the early stages of the disease. However, under the selective pressure of androgen withdrawal, androgen-dependent CaP can progress to an androgen-independent CaP. Androgen-independent CaP is invariably a more aggressive and untreatable form of the disease. Advancing our understanding of the molecular mechanisms behind the switch in androgen-dependency would improve our success of treating CaP and other AR related illnesses. This study evaluates how clinically identified AR mutations affect the receptor s transcriptional activity. We reveal that a potential molecular abnormality in androgen insensitivity syndrome and CaP patients is caused by disruptions of the important intra-receptor NTD/LBD interaction. We demonstrate that the same AR LBD mutations can also disrupt the recruitment of the p160 coactivator protein GRIP1. Our investigations reveal that 30% of patients with advanced, untreated local CaP have somatic mutations that may lead to increases in AR activity. We report that somatic mutations that activate AR may lead to early relapse in ADT. Our results demonstrate that the types of ADT a CaP patient receives may cause a clustering of mutations to a particular region of the receptor. Furthermore, the mutations that arise before and during ADT do not always result in a receptor that is more active, indicating that coregulator interactions play a pivotal role in the progression of androgen-independent CaP. To improve CaP therapy, it is necessary to identify critical coregulators of AR. We screened a HeLa cell cDNA library and identified small carboxyl-terminal domain phosphatase 2 (SCP2). SCP2 is a protein phosphatase that directly interacts with the AR NTD and represses AR activity. We demonstrated that reducing the endogenous cellular levels of SCP2 causes more AR to load on to the prostate specific antigen (PSA) gene promoter and enhancer regions. Additionally, under the same conditions, more RNA polymerase II was recruited to the PSA promoter region and overall there was an increase in androgen-dependent transcription of the PSA gene, revealing that SCP2 could play a role in the pathogenesis of CaP.

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Skeletal muscle cells are highly specialised in order to accomplish their function. During development, the fusion of hundreds of immature myoblasts creates large syncytial myofibres with a highly ordered cytoplasm filled with packed myofibrils. The assembly and organisation of contractile myofibrils must be tightly controlled. Indeed, the number of proteins involved in sarcomere building is impressive, and the role of many of them has only recently begun to be elucidated. Myotilin was originally identified as a high affinity a-actinin binding protein in yeast twohybrid screen. It was then found to interact also with filamin C, actin, ZASP and FATZ-1. Human myotilin is mainly expressed in striated muscle and induces efficient actin bundling in vitro and in cells. Moreover, mutations in myotilin cause different forms of muscle disease, now collectively known as myotilinopathies. In this thesis, consisting of three publications, the work on the mouse orthologue is presented. First, the cloning and molecular characterisation of the mouse myotilin gene showed that human and mouse myotilin share high sequence homology and a similar expression pattern and gene regulation. Functional analysis of the mouse promoter revealed the myogenic factor-binding elements that are required for myotilin gene transcription. Secondly, expression of myotilin was studied during mouse embryogenesis. Surprisingly, myotilin was expressed in a wide array of tissues at some stages of development; its expression pattern became more restricted at perinatal stages and in adult life. Immunostaining of human embryos confirmed broader myotilin expression compared to the sarcomeric marker titin. Finally, in the third article, targeted deletion of myotilin gene in mice revealed that it is not essential for muscle development and function. These data altogether indicate that the mouse can be used as a model for human myotilinopathy and that loss of myotilin does not alter significantly muscle structure and function. Therefore, disease-associated mutant myotilin may act as a dominant myopathic factor.

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The basis for this study was in poor attractiveness of the wood products industry among young people as a field to study and work in. The purpose was to produce new information of how to improve the relationship between young people and the wood products industry in order to better attract young people with different relational orientation. A survey was conducted among students of comprehensive schools and students of wood industry at vocational schools selected by systematic cluster sampling. The final sample consisted of 613 students. The study combined the theories and concepts of relationships, communication and trust of several disciplines. In addition, it applied theories of relationship marketing, stakeholders, publics, involvement and concepts of reputation and values. It studied the central relational elements in the form of antecedents, relationship state and its consequences. The study examined, how young people with different background and level of interest perceive wood industry as a field to study and work in from relational point of view, what are the central deficiencies in perceived relational elements and what are the public relations activities enhancing the relationship between wood industry and young people with less and high interest in the sector. The results indicate poor visibility of the wood industry among young people: unfamiliarity with the industry and unawareness of the opportunities to study in the field. It appeared that instead of increasing only information sharing, interactive communication in different forms is needed. The study also suggests that behaviors of the industry sector advancing perceived trustworthiness are of crucial importance. Moreover, the wood industry needs to pay attention to its behaviors and communication also among other stakeholder groups, especially the media, as reputation plays an important role in building up trust and satisfaction between young people and the sector. Finally, the less and highly interested young people were found to assess the relationship partly through different relational elements. In order to develop the relationship with highly interested young people they should be regarded clearly as future employees of the wood industry through activities affirming that they are desired and valued employees in the sector. Further, openness of information disclosure, whether concerning current situation or future prospects, seems to increase credibility and attractiveness of the wood industry. Highly interested young people were also found to appreciate socially responsible activities. The less interested young people seem to be insecure about the reliability of the wood industry as an employer, as well as, its ability and interest to invest in young people s skills. In addition,involvement in issues relevant for young people was found crucial in enhancing the relationship with the less interested young people.The conclusions of the study provide tools for enhancing the attractiveness of the wood industry among young people not only to the industry itself, but also to its advocates, teachers and student counselors of comprehensive and vocational schools, authorities and policy makers.

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In this work, separation methods have been developed for the analysis of anthropogenic transuranium elements plutonium, americium, curium and neptunium from environmental samples contaminated by global nuclear weapons testing and the Chernobyl accident. The analytical methods utilized in this study are based on extraction chromatography. Highly varying atmospheric plutonium isotope concentrations and activity ratios were found at both Kurchatov (Kazakhstan), near the former Semipalatinsk test site, and Sodankylä (Finland). The origin of plutonium is almost impossible to identify at Kurchatov, since hundreds of nuclear tests were performed at the Semipalatinsk test site. In Sodankylä, plutonium in the surface air originated from nuclear weapons testing, conducted mostly by USSR and USA before the sampling year 1963. The variation in americium, curium and neptunium concentrations was great as well in peat samples collected in southern and central Finland in 1986 immediately after the Chernobyl accident. The main source of transuranium contamination in peats was from global nuclear test fallout, although there are wide regional differences in the fraction of Chernobyl-originated activity (of the total activity) for americium, curium and neptunium.

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Recent epidemiological studies have shown a consistent association of the mass concentration of urban air thoracic (PM10) and fine (PM2.5) particles with mortality and morbidity among cardiorespiratory patients. However, the chemical characteristics of different particulate size ranges and the biological mechanisms responsible for these adverse health effects are not well known. The principal aims of this thesis were to validate a high volume cascade impactor (HVCI) for the collection of particulate matter for physicochemical and toxicological studies, and to make an in-depth chemical and source characterisation of samples collected during different pollution situations. The particulate samples were collected with the HVCI, virtual impactors and a Berner low pressure impactor in six European cities: Helsinki, Duisburg, Prague, Amsterdam, Barcelona and Athens. The samples were analysed for particle mass, common ions, total and water-soluble elements as well as elemental and organic carbon. Laboratory calibration and field comparisons indicated that the HVCI can provide a unique large capacity, high efficiency sampling of size-segregated aerosol particles. The cutoff sizes of the recommended HVCI configuration were 2.4, 0.9 and 0.2 μm. The HVCI mass concentrations were in a good agreement with the reference methods, but the chemical composition of especially the fine particulate samples showed some differences. This implies that the chemical characterization of the exposure variable in toxicological studies needs to be done from the same HVCI samples as used in cell and animal studies. The data from parallel, low volume reference samplers provide valuable additional information for chemical mass closure and source assessment. The major components of PM2.5 in the virtual impactor samples were carbonaceous compounds, secondary inorganic ions and sea salt, whereas those of coarse particles (PM2.5-10) were soil-derived compounds, carbonaceous compounds, sea salt and nitrate. The major and minor components together accounted for 77-106% and 77-96% of the gravimetrically-measured masses of fine and coarse particles, respectively. Relatively large differences between sampling campaigns were observed in the organic carbon content of the PM2.5 samples as well as the mineral composition of the PM2.5-10 samples. A source assessment based on chemical tracers suggested clear differences in the dominant sources (e.g. traffic, residential heating with solid fuels, metal industry plants, regional or long-range transport) between the sampling campaigns. In summary, the field campaigns exhibited different profiles with regard to particulate sources, size distribution and chemical composition, thus, providing a highly useful setup for toxicological studies on the size-segregated HVCI samples.

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Photocatalytic TiO2 thin films can be highly useful in many environments and applications. They can be used as self-cleaning coatings on top of glass, tiles and steel to reduce the amount of fouling on these surfaces. Photocatalytic TiO2 surfaces have antimicrobial properties making them potentially useful in hospitals, bathrooms and many other places where microbes may cause problems. TiO2 photocatalysts can also be used to clean contaminated water and air. Photocatalytic oxidation and reduction reactions proceed on TiO2 surfaces under irradiation of UV light meaning that sunlight and even normal indoor lighting can be utilized. In order to improve the photocatalytic properties of TiO2 materials even further, various modification methods have been explored. Doping with elements such as nitrogen, sulfur and fluorine, and preparation of different kinds of composites are typical approaches that have been employed. Photocatalytic TiO2 nanotubes and other nanostructures are gaining interest as well. Atomic Layer Deposition (ALD) is a chemical gas phase thin film deposition method with strong roots in Finland. This unique modification of the common Chemical Vapor Deposition (CVD) method is based on alternate supply of precursor vapors to the substrate which forces the film growth reactions to proceed only on the surface in a highly controlled manner. ALD gives easy and accurate film thickness control, excellent large area uniformity and unparalleled conformality on complex shaped substrates. These characteristics have recently led to several breakthroughs in microelectronics, nanotechnology and many other areas. In this work, the utilization of ALD to prepare photocatalytic TiO2 thin films was studied in detail. Undoped as well as nitrogen, sulfur and fluorine doped TiO2 thin films were prepared and thoroughly characterized. ALD prepared undoped TiO2 films were shown to exhibit good photocatalytic activities. Of the studied dopants, sulfur and fluorine were identified as much better choices than nitrogen. Nanostructured TiO2 photocatalysts were prepared through template directed deposition on various complex shaped substrates by exploiting the good qualities of ALD. A clear enhancement in the photocatalytic activity was achieved with these nanostructures. Several new ALD processes were also developed in this work. TiO2 processes based on two new titanium precursors, Ti(OMe)4 and TiF4, were shown to exhibit saturative ALD-type of growth when water was used as the other precursor. In addition, TiS2 thin films were prepared for the first time by ALD using TiCl4 and H2S as precursors. Ti1-xNbxOy and Ti1-xTaxOy transparent conducting oxide films were prepared successfully by ALD and post-deposition annealing. Highly unusual, explosive crystallization behaviour occurred in these mixed oxides which resulted in anatase crystals with lateral dimensions over 1000 times the film thickness.

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The present study examines how the landscape of the rural immigrant colony of New Finland (Saskatchewan, Canada) has reflected the Finnish origins of the about 350 settlers and their descendants, their changing ideologies, values, sense of collectiveness and the meanings of the Finnish roots. The study also reveals the reasons and power structures behind the ethnic expressions. Researched time period runs from the beginning of the settlement in 1888 to the turn of the millennium. The research concentrates on buildings, cemeteries, personal names and place names which contain strong visual and symbolic messages and are all important constituents of mundane landscapes. For example, the studied personal names are important identity-political indexes telling about the value of the Finnish nationalism, community spirit, dual Finnish-Canadian identities and also the process of assimilation which, for example, had differences between genders. The study is based on empirical field research, and iconographical and textual interpretations supported by classifications and comparative analyses. Several interviews and literature were essential means of understanding the changing political contexts which influenced the Finnish settlement and its multiple landscape representations. Five historical landscape periods were identified in New Finland. During these periods the meanings and representations of Finnish identity changed along with national and international politics and local power structures. For example, during the Second World War Canada discouraged representations of Finnish culture because Finland and Canada were enemies. But Canada s multicultural policy in the 1980s led to several material and symbolic representations indicating the Finnish settlement after a period of assimilation and deinstitutionalization. The study shows how these representations were indications of the politics of a (selective) memory. Especially Finnish language, cultural traditions and the Evangelical-Lutheran values of the pioneers, which have been passed down to new generations, are highly valued part of the Finnish heritage. Also the work of the pioneers and their participation in the building of Saskatchewan is an important collective narrative. The selectiveness of a memory created the landscape of forgetting which includes deliberately forgotten parts of the history. For example, the occasional disputes between the congregations are something that has been ignored. The results show how the different landscape elements can open up a useful perspective to diaspora colonies or other communities also by providing information which otherwise would be indistinguishable. In this case, for example, two cemeteries close together were a sign of religious distributions among the early settlers.