987 resultados para TE and TM polarisations


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Myeloproliferative neoplasms (MPN) and myelodysplastic syndromes (MDS) are a heterogeneous group of clonal hematopoietic disorders whose etiology and molecular pathogenesis are poorly understood. During the past decade, enormous developments in microarray technology and bioinformatics methods have made it possible to mine novel molecular alterations in a large number of malignancies, including MPN and MDS, which has facilitated the detection of new prognostic, predictive and therapeutic biomarkers for disease stratification. By applying novel microarray techniques, we profiled copy number alterations and microRNA (miRNA) expression changes in bone marrow aspirate and blood samples. In addition, we set up and validated an miRNA expression test for bone marrow core biopsies in order to utilize the large archive material available in many laboratories. We also tested JAK2 mutation status and compare it with the in vitro growth pattern of hematologic progenitors cells. In the study focusing on 100 MPN cases, we detected a Janus kinase 2 (JAK2) mutation in 71 cases. We observed spontaneous erythroid colony growth in all mutation-positive cases in addition to nine mutation negative cases. Interestingly, seven JAK2V167F negative ET cases showed spontaneous megakaryocyte colony formation, one case of which also harbored a myeloproliferative leukemia virus oncogene (MPL) mutation. We studied copy number alterations in 35 MPN and 37 MDS cases by using oligonucleotide-based array comparative hybridization (array CGH). Only one essential thrombocythemia (ET) case presented copy number alterations in chromosomes 1q and 13q. In contrast, MDS cases were characterized by numerous novel cryptic chromosomal aberrations with the most common copy number losses at 5q21.3q33.1 and 7q22.1q33, while the most common copy number gain was trisomy 8. As for the study of the bone marrow core biopsy samples, we showed that even though these samples were embedded in paraffin and underwent decalcification, they were reliable sources of miRNA and suitable for array expression analysis. Further, when studying the miRNA expression profiles of the 19 MDS cases, we found that, compared to controls, two miRNAs (one human Epstein-Barr virus (miR-BART13) miRNA and one human (has-miR-671-5p) miRNA) were downregulated, whereas two other miRNAs (hsa-miR-720 and hsa-miR-21) were upregulated. However, we could find no correlation between copy number alterations and microRNA expression when integrating these two data. This thesis brings to light new information about genomic changes implicated in the development of MPN and MDS, and also underlines the power of applying genome-wide array screening techniques in neoplasias. Rapid advances in molecular techniques and the integration of different genomic data will enable the discovery of the biological contexts of many complex disorders, including myeloid neoplasias.

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The relationship between the Orthodox Churches and the World Council of Churches (WCC) became a crisis just before the 8th Assembly of the WCC in Harare, Zimbabwe in 1998. The Special Commission on Orthodox Participation in the WCC (SC), inaugurated in Harare, worked during the period 1999 2002 to solve the crisis and to secure the Orthodox participation in the WCC. The purpose of this study is: 1) to clarify the theological motives for the inauguration of the SC and the theological argumentation of the Orthodox criticism; 2) to write a reliable history and analysis of the SC; 3) to outline the theological argumentation, which structures the debate, and 4) to investigate the ecclesiological questions that arise from the SC material. The study spans the years 1998 to 2006, from the WCC Harare Assembly to the Porto Alegre Assembly. Hence, the initiation and immediate reception of the Special Commission are included in the study. The sources of this study are all the material produced by and for the SC. The method employed is systematic analysis. The focus of the study is on theological argumentation; the historical context and political motives that played a part in the Orthodox-WCC relations are not discussed in detail. The study shows how the initial, specific and individual Orthodox concerns developed into a profound ecclesiological discussion and also led to concrete changes in WCC practices, the best known of which is the change to decision-making by consensus. The Final Report of the SC contains five main themes, namely, ecclesiology, decision-making, worship/common prayer, membership and representation, and social and ethical issues. The main achievement of the SC was that it secured the Orthodox membership in the WCC. The ecclesiological conclusions made in the Final Report are twofold. On the one hand, it confirms that the very act of belonging to the WCC means the commitment to discuss the relationship between a church and churches. The SC recommended that baptism should be added as a criterion for membership in the WCC, and the member churches should continue to work towards the mutual recognition of each other s baptism. These elements strengthen the ecclesiological character of the WCC. On the other hand, when the Final Report discusses common prayer, the ecclesiological conclusions are much more cautious, and the ecclesiological neutrality of the WCC is emphasized several times. The SC repeatedly emphasized that the WCC is a fellowship of churches. The concept of koinonia, which has otherwise been important in recent ecclesiological questions, was not much applied by the SC. The comparison of the results of the SC to parallel ecclesiological documents of the WCC (Nature and Mission of the Church, Called to Be the One Church) shows that they all acknowledge the different ecclesiological starting points of the member churches, and, following that, a variety of legitimate views on the relation of the Church to the churches. Despite the change from preserving the koinonia to promises of eschatological koinonia, all the documents affirm that the goal of the ecumenical movement is still full, visible unity.

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This thesis studies the basic income grant proposal in Namibia. The proposal suggests a monthly grant of N$100 (approximately 10€) to all those Namibian citizens who do not receive the state pension. This thesis concentrates on the Basic Income Grant (BIG) Coalition and on its work. The formation and transformation of the coalition during the time period between 2003 and 2009 is analyzed with the help of data collected during two field work periods in 2008 and 2009. The data includes interviews, newspaper articles, observations and other background material. The analysis of this material is mainly conducted from organizational viewpoint. The final part of the thesis applies the results to the theory of Mosse, whose propositions about policy and practice will be discussed in relation to the basic income grant pilot project. The thesis argues that social legitimacy has been a vital resource for the work of the BIG Coalition and it has sought for it in various ways. The concept of social legitimacy originates from the resource dependence perspective of Pfeffer and Salancik, who propose that organizations are dependent on their environments, and on the resources provided by the surrounding environment. This thesis studies the concept of social legitimacy in the context of resource dependence theory. Social legitimacy is analyzed in the relations between the coalition and its environment, in the formation of the coalition, in the responses towards criticism, and finally in relation to the propositions concerning policy and practice. The work of the coalition in the pilot project will be analyzed through the propositions of Mosse concerning policy and practice. The results will describe and analyze key events in the formation of the BIG Coalition from the South African proposal until the end of the basic income pilot project. This BIG pilot project conducted in 2008-2009 is one of the most well-known activities of the coalition. The clashes between the coalition and its environment will be analyzed through four case studies. It will be shown that the project has been conducted in order to gain more legitimacy to the basic income grant proposal. The conclusion questions the legitimacy of the BIG Coalition as a research and development organization, and requests for more transparent research on the basic income proposal in Namibia.

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The tourism development nexus in southern Africa involves highly topical issues related to tourism planning, power relations, community participation, and natural resources. Namibia offers a particularly interesting context for the study of these issues due to its colonial legacy, vast tourism potential, recently adopted tourism policy and community-based approaches to tourism and natural resource management. This study is an interdisciplinary endeavour to analyse the role of tourism in Namibia s post-apartheid transformation process by focusing on Namibian tourism policy and local tourism enterprises' policy knowledge. Major attention is paid to how the tourism policy's national development objectives are understood and conceptualised by the representatives of different tourism enterprises and the ways in which they relate to the practical needs of the enterprises. Through such local policy knowledge the study explores various opportunities, challenges and constraints related to the promotion of tourism as a development strategy. The study utilises a political economy approach to tourism and development through three current and interrelated discourses which are relevant in the Namibian context. These are tourism, power and inequality, tourism and sustainable development, and tourism and poverty reduction. The qualitative research material was gathered in Namibia in 2006-2007 and 2008. This material consists of 34 semi-structured interviews in 16 tourism enterprises, including private trophy hunting farms and private lodges, small tour operators and community-based tourism enterprises. In addition, the research material consists of observations in the enterprises, and 37 informal and 23 expert interviews. The findings indicate that in the light of local tourism enterprises the tourism policy objectives appear more complex and ambiguous. Furthermore, they involve multiple meanings and interpretations which reflect the socio-economic stratification of the informants and Namibian society, together with the professional stratification of the tourism enterprises and restrictions on the capacity of tourism to address the development objectives. In the light of such findings it is obvious that aspects of power and inequality affect the tourism development nexus in Namibia. The study concludes that, as in the case of other southern African countries, in order to promote sustainable development and reduce poverty, Namibia should not only target tourism growth but pay attention to who benefits from that growth and how. From a political economy point of view, it is important that prevailing structural challenges are addressed equally in the planning of tourism, development and natural resource management. Such approach would help the Namibian majority to enjoy the benefits of increasing tourism in the country.

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In meteorology, observations and forecasts of a wide range of phenomena for example, snow, clouds, hail, fog, and tornados can be categorical, that is, they can only have discrete values (e.g., "snow" and "no snow"). Concentrating on satellite-based snow and cloud analyses, this thesis explores methods that have been developed for evaluation of categorical products and analyses. Different algorithms for satellite products generate different results; sometimes the differences are subtle, sometimes all too visible. In addition to differences between algorithms, the satellite products are influenced by physical processes and conditions, such as diurnal and seasonal variation in solar radiation, topography, and land use. The analysis of satellite-based snow cover analyses from NOAA, NASA, and EUMETSAT, and snow analyses for numerical weather prediction models from FMI and ECMWF was complicated by the fact that we did not have the true knowledge of snow extent, and we were forced simply to measure the agreement between different products. The Sammon mapping, a multidimensional scaling method, was then used to visualize the differences between different products. The trustworthiness of the results for cloud analyses [EUMETSAT Meteorological Products Extraction Facility cloud mask (MPEF), together with the Nowcasting Satellite Application Facility (SAFNWC) cloud masks provided by Météo-France (SAFNWC/MSG) and the Swedish Meteorological and Hydrological Institute (SAFNWC/PPS)] compared with ceilometers of the Helsinki Testbed was estimated by constructing confidence intervals (CIs). Bootstrapping, a statistical resampling method, was used to construct CIs, especially in the presence of spatial and temporal correlation. The reference data for validation are constantly in short supply. In general, the needs of a particular project drive the requirements for evaluation, for example, for the accuracy and the timeliness of the particular data and methods. In this vein, we discuss tentatively how data provided by general public, e.g., photos shared on the Internet photo-sharing service Flickr, can be used as a new source for validation. Results show that they are of reasonable quality and their use for case studies can be warmly recommended. Last, the use of cluster analysis on meteorological in-situ measurements was explored. The Autoclass algorithm was used to construct compact representations of synoptic conditions of fog at Finnish airports.

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Tämä työ tarkastelee kansallista ja paikallista omistajuutta Namibian opetussektorin kehittämisohjelmassa. Opetussektorin kehittämisohjelma ETSIP on 15-vuotinen sektoriohjelma vuosille 2005-2015 ja sen tavoitteena on edesauttaa Namibian kehittymistä tietoyhteiskunnaksi. Tutkimuksen tarkoituksena on selvittää miten kansallinen ja paikallinen omistajuus on toteutunut ETSIP prosessin aikana. Erityisesti pyritään selvittämään paikallistason opetussektorin virkamiesten näkemyksiä ETSIP prosessista, heidän roolistaan siinä ja siitä millaisia vaikuttamisen ja hallinnan mahdollisuuksia heillä on ollut prosessin aikana. Tutkimuksen lähtökohta on laadullinen ja lähestymistapa konstruktionistinen: tutkimus tarkastelee todellisuutta ihmisten kokemusten, näkemysten ja toiminnan kautta. Tutkimusaineisto koostuu haastatteluista, epävirallisista keskusteluista, lehtiartikkeleista ja ETSIP dokumenteista. Tutkimus osoittaa että kansallinen omistajuus on epämääräinen käsite sillä kansallisia toimijoita ja näkemyksiä on useita. Tutkimus vahvistaa Castel-Brancon huomion siitä, että omistajuutta on tarkasteltava kontekstissaan: muuttuvana ja kilpailtuna. ETSIPin rinnalle ollaan valmistelemassa uutta strategista ohjelmaa opetusministeriölle mikä saattaa muuttaa omistajuutta ETSIPiin. ETSIP dokumenttien omistajuusretoriikka myötäilee kansainvälisiä sitoumuksia avun vaikuttavuuden parantamiseksi mutta niistä puuttuu syvällisempi analyysi siitä, miten kansallinen ja paikallinen omistajuus toteutuisi käytännössä. Avunantajien näkemys omistajuudesta on suppea: omistajuus nähdään lähinnä sitoutumisena ennalta määrättyyn politiikkaohjelmaan. Haastatteluaineistosta nousee esiin Whitfieldin ja Frazerin jaottelu suppeista ja laajoista omistajuuskäsityksistä. Sitoutumista ETSIP ohjelmaan pidetään tärkeänä mutta riittämättömänä määritteenä omistajuudelle. Paikallisella tasolla sitoutuminen ETSIP ohjelman periaatteisiin ja tavoitteisiin on toteutunut melko hyvin mutta jos omistajuutta tarkastellaan laajemmin vaikutusvallan ja hallinnan käsitteiden kautta voidaan todeta että omistajuus on ollut heikkoa. Paikallisella tasolla ei ole ollut juurikaan vaikutusvaltaa ETSIP ohjelman sisältöön eikä mahdollisuutta hallita ohjelman toteutusta ja päättää siitä mitä hankkeita ohjelman kautta rahoitetaan. Tujanin demokraattisen omistajuuden käsite kuvaa tarvetta muuttaa ja laajentaa omistajuusajattelua huomioiden paikallisen tason paremmin. Tämä tutkimus viittaa siihen että omistajuuden toteutuminen paikallisella tasolla edellyttäisi institutionaalisen kulttuurin muutosta ja institutionaalisen legitimiteetin vahvistamista. Omistajuuden mahdollistamiseksi paikallisella tasolla tarvittaisiin poliittista johtajuutta, luottamusta, vastuullisuuden kulttuurin kehittämistä, tehokkaampaa tiedonjakoa, laajaa osallistumista, vuoropuhelua ja yhteistyötä. Ennen kaikkea tarvittaisiin paikallisen tason vaikutusvaltaa päätöksenteossa ja kontrollia resurssien käytöstä. Tälle muutokselle on selvä tarve ja tilaus.

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The most prominent objective of the thesis is the development of the generalized descriptive set theory, as we call it. There, we study the space of all functions from a fixed uncountable cardinal to itself, or to a finite set of size two. These correspond to generalized notions of the universal Baire space (functions from natural numbers to themselves with the product topology) and the Cantor space (functions from natural numbers to the {0,1}-set) respectively. We generalize the notion of Borel sets in three different ways and study the corresponding Borel structures with the aims of generalizing classical theorems of descriptive set theory or providing counter examples. In particular we are interested in equivalence relations on these spaces and their Borel reducibility to each other. The last chapter shows, using game-theoretic techniques, that the order of Borel equivalence relations under Borel reduciblity has very high complexity. The techniques in the above described set theoretical side of the thesis include forcing, general topological notions such as meager sets and combinatorial games of infinite length. By coding uncountable models to functions, we are able to apply the understanding of the generalized descriptive set theory to the model theory of uncountable models. The links between the theorems of model theory (including Shelah's classification theory) and the theorems in pure set theory are provided using game theoretic techniques from Ehrenfeucht-Fraïssé games in model theory to cub-games in set theory. The bottom line of the research declairs that the descriptive (set theoretic) complexity of an isomorphism relation of a first-order definable model class goes in synch with the stability theoretical complexity of the corresponding first-order theory. The first chapter of the thesis has slightly different focus and is purely concerned with a certain modification of the well known Ehrenfeucht-Fraïssé games. There we (me and my supervisor Tapani Hyttinen) answer some natural questions about that game mainly concerning determinacy and its relation to the standard EF-game

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The human gastrointestinal (GI) microbiota is a complex ecosystem that lives in symbiosis with its host. The growing awareness of the importance of the microbiota to the host as well as the development of culture-free laboratory techniques and computational methods has enormously expanded our knowledge of this microbial community. Irritable bowel syndrome (IBS) is a common functional bowel disorder affecting up to a fifth of the Western population. To date, IBS diagnosis has been based on GI symptoms and the exclusion of organic diseases. The GI microbiota has been found to be altered in this syndrome and probiotics can alleviate the symptoms, although clear links between the symptoms and the microbiota have not been demonstrated. The aim of the present work was to characterise IBS related alterations in the intestinal microbiota, their relation to IBS symptoms and their responsiveness to probiotic theraphy. In this thesis research, the healthy human microbiota was characterised by cloning and sequencing 16S rRNA genes from a faecal microbial community DNA pool that was first profiled and fractionated according to its guanine and cytosine content (%G+C). The most noticeable finding was that the high G+C Gram-positive bacteria (the phylum Actinobacteria) were more abundant compared to a corresponding library constructed from the unfractionated DNA pool sample. Previous molecular analyses of the gut microbiota have also shown comparatively low amounts of high G+C bacteria. Furthermore, the %G+C profiling approach was applied to a sample constructed of faecal DNA from diarrhea-predominant IBS (IBS-D) subjects. The phylogenetic microbial community comparison performed for healthy and IBS-D sequence libraries revealed that the IBS-D sample was rich in representatives of the phyla Firmicutes and Proteobacteria whereas Actinobacteria and Bacteroidetes were abundant in the healthy subjects. The family Lachnospiraceae within the Firmicutes was especially prevalent in the IBS-D sample. Moreover, associations of the GI microbiota with intestinal symptoms and the quality of life (QOL) were investigated, as well as the effect of probiotics on these factors. The microbial targets that were analysed with the quantitative real-time polymerase chain reaction (qPCR) in this study were phylotypes (species definition according to 16S rRNA gene sequence similarity) previously associated with either health or IBS. With a set of samples, the presence or abundance of a phylotype that had 94% 16S rRNA gene sequence similarity to Ruminococcus torques (R. torques 94%) was shown to be associated with the severity of IBS symptoms. The qPCR analyses for selected phylotypes were also applied to samples from a six-month probiotic intervention with a mixture of Lactobacillus rhamnosus GG, L. rhamnosus Lc705, Propionibacterium freudenreichii ssp. shermanii JS and Bifidobacterium breve Bb99. The intervention had been previously reported to alleviate IBS symptoms, but no associations with the analysed microbiota representatives were shown. However, with the phylotype-specific assays applied here, the abundance of the R. torques 94% -phylotype was shown to be lowered in the probiotic-receiving group during the probiotic supplementation, whereas a Clostridium thermosuccinogenes 85% phylotype, previously associated with a healthy microbiota, was found to be increased compared to the placebo group. To conclude, with the combination of methods applied, higher abundance of Actinobacteria was detected in the healthy gut than found in previous studies, and significant phylum-level microbiota alterations could be shown in IBS-D. Thus, the results of this study provide a detailed overview of the human GI microbiota in healthy subjects and in subjects with IBS. Furthermore, the IBS symptoms were linked to a particular clostridial phylotype, and probiotic supplementation was demonstrated to alter the GI microbiota towards a healthier state with regard to this and an additional bacterial phylotype. For the first time, distinct phylotype-level alterations in the microbiota were linked to IBS symptoms and shown to respond to probiotic therapy.

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Tutkimuksessa analysoin neljää Jeff Lindsayn Dexter -dekkaria kahdesta eri näkökulmasta. Ensimmäinen osa keskittyy päähenkilön sosiopaattisen persoonan aiheuttamiin moraalisiin ristiriitoihin, sillä hän on sekä sarjamurhaaja että työskentelee poliisin laboratoriossa silti noudattaen erittäin tiukkaa moraalista ohjenuoraa, joka määrittää kenet hän saa tappaa. Tutkimuksen toinen osa tarkastelee kirjojen naishahmoja ja heidän ongelmiaan. Käsittelen lyhyesti myös kirjasarjan ja niiden pohjalta tehdyn televisiosarjan eroja. Metodeina käytän lähiluentaa, eettistä analyysiä sekä rikoskirjallisuuden alalajien vertailua. Vaikkei rikoskirjallisuudessa olekaan yleistä, että poliisi tai tutkija olisi siviilissä rikollinen, on Dexter hyvin tyypillinen fiktiivinen sosiopaatti ja sarjamurhaaja. Lindsayn kirjojen juonet ja Dexter päähenkilönä noudattavat paikoin lähes kirjaimellisesti Thomas Harrisin Hannibal Lecterille luomaa kaavaa. Kirjojen moraaliset ristiriidat taas aiheutuvat sekä Dexterin roolista lainvartijana ja -rikkojana että hänen noudattamastaan tiukasta moraalisesta ohjenuorasta, joka määrittää kenet saa tappaa. Sosiopaattina hänen pitäisi olla kaikkien yhteiskunnan asettamien lakien ja rajoitusten tavoittamattomissa, mutta silti hänen päätöksentekonsa perustuu täysin kasvatti-isänsä laatimiin ohjeisiin. Tämä on yksi Dexterin hahmon suurimmista ristiriitaisuuksista, joka vahvistaa Heta Pyrhösen esittämän ajatuksen siitä, ettei rikoskirjallisuus tule toimeen ilman vahvaa moraalista selkärankaa. Dexterin tiukka moraalinen ohjenuora ja lukijoiden samaistuminen päähenkilöön ovat kuitenkin todennäköisin syy hänen selviytymiseensä kirjasta toiseen, ja sarjan myötä Dexter muuttuukin inhimillisemmäksi kuin alussa. Toisaalta naishahmojen ongelmien havaitseminen on vaikeaa, sillä ensivaikutelman perusteella voisi kuvitella, että Lindsayn kuvaama yhteiskunta on jo ratkaissut kaikki tasa-arvo-ongelmansa. Sukupuolten ja kansanryhmien välisestä tasa-arvosta ei kirjoissa keskustella, mutta merkittäviä naishahmoja on silti huomattavan vähän, eikä heistäkään ole rakennettu yhtä johdonmukaisia ja mielenkiintoisia kuin päähenkilöstä esimerkiksi. He jäävät pitkälti Dexterin varjoon. Edes Dexterin sisko Deborah ei pysty säilyttämään osaansa kirjojen naispäähenkilönä, sillä hänen ammattitaitoaan poliisina ja olemustaan naisena kuvataan jatkuvan ristiriitaisesti. Kaksi seuraavaksi tärkeintä naishahmoa ovat Dexterin tyttöystävä Rita, joka toimii äitiyden ruumiillistumana, sekä hänen tyttärensä Astor, joka on veljensä ohella samanlainen sosiopaatti kuin Dexter. Naissarjamurhaajien puute ja naishahmojen epäjohdonmukainen kuvaus ovat yksi Lindsayn kirjojen suurimmista ongelmista. Analyysin keskeisimmät johtopäätökset paljastavat, miten omaperäisyydestään huolimatta Dexter muistuttaa huomattavasti muita tunnettuja fiktiivisiä sarjamurhaajia, ja miten Lindsay pohjaa tekstinsä amerikkalaiseen arvomaailmaan ja rikoskirjallisuuden alalajien konventioihin. Vaikka suurin osa lukijoista pystyykin käsittelemään Dexterin tekojen moraalisia ristiriitoja, voi sarjamurhaajan ihannointi aiheuttaa toisille ongelmia. Toisaalta luomalla monipuolisia ja johdonmukaisia naishahmoja, jotka pystyisivät säilyttämään itsenäisyytensä kaikissa tilanteissa, Lindsayn kirjat olisivat sekä ajankohtaisempia että omaperäisempiä kuin nyt.

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In order to evaluate the influence of ambient aerosol particles on cloud formation, climate and human health, detailed information about the concentration and composition of ambient aerosol particles is needed. The dura-tion of aerosol formation, growth and removal processes in the atmosphere range from minutes to hours, which highlights the need for high-time-resolution data in order to understand the underlying processes. This thesis focuses on characterization of ambient levels, size distributions and sources of water-soluble organic carbon (WSOC) in ambient aerosols. The results show that in the location of this study typically 50-60 % of organic carbon in fine particles is water-soluble. The amount of WSOC was observed to increase as aerosols age, likely due to further oxidation of organic compounds. In the boreal region the main sources of WSOC were biomass burning during the winter and secondary aerosol formation during the summer. WSOC was mainly attributed to a fine particle mode between 0.1 - 1 μm, although different size distributions were measured for different sources. The WSOC concentrations and size distributions had a clear seasonal variation. Another main focus of this thesis was to test and further develop the high-time-resolution methods for chemical characterization of ambient aerosol particles. The concentrations of the main chemical components (ions, OC, EC) of ambient aerosol particles were measured online during a year-long intensive measurement campaign conducted on the SMEAR III station in Southern Finland. The results were compared to the results of traditional filter collections in order to study sampling artifacts and limitations related to each method. To achieve better a time resolution for the WSOC and ion measurements, a particle-into-liquid sampler (PILS) was coupled with a total organic carbon analyzer (TOC) and two ion chromatographs (IC). The PILS-TOC-IC provided important data about diurnal variations and short-time plumes, which cannot be resolved from the filter samples. In summary, the measurements made for this thesis provide new information on the concentrations, size distribu-tions and sources of WSOC in ambient aerosol particles in the boreal region. The analytical and collection me-thods needed for the online characterization of aerosol chemical composition were further developed in order to provide more reliable high-time-resolution measurements.

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Hostility is a multidimensional construct having wide effects on society. In its different forms, hostility is related to a large array of social and health problems, such as criminality, substance abuse, depression, and cardiovascular risks. Identifying and tackling early-life factors that contribute to hostility may have public health significance. Although the variance in hostility is estimated to be 18-50 percent heritable, there are significant gaps in knowledge regarding the molecular genetics of hostility. It is known that a cold and unsupportive home atmosphere in childhood predicts a child s later hostility. However, the long-term effects of care-giving quality on hostility in adulthood and the role of genes in this association are unclear. The present dissertation is part of the ongoing population-based prospective Young Finns study, which commenced in 1980 with 3596 3-18-year-old boys and girls who were followed for 27 years. The specific aims of the dissertation were first to study the antecedents of hostility by looking at 1) the genetic background, 2) the early environmental predictors, and 3) the gene environment interplay behind hostility. As a second aim, the thesis endeavored to examine 4) the association between hostility and cardiovascular risks, and 5) the moderating effect of demographic factors, such as gender and socioeconomic status, on this association. The study found potential gene polymorphisms from chromosomes 7, 14, 17, and 22 suggestively associated with hostility. Of early environmental influences, breastfeeding and early care-giving were found to predict hostility in adulthood. In addition, a serotonin receptor 2A polymorphism rs6313 moderated the effect of early care-giving on later hostile attitudes. Furthermore, hostility was shown to predict cardiovascular risks, such as metabolic syndrome and inflammation. Finally, parental socioeconomic status was found to moderate the association between anger and early atherosclerosis. The new genetic and early environmental antecedents of hostility identified in this research may help in understanding the development of hostility and its health risks, and in planning appropriate prevention. The significance of early influences on this development is stressed. Although the markers studied are individual- and family-related factors, these may be influenced at the societal level by giving accurate information to all individuals concerned and by improving the societal circumstances.

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Biological membranes are tightly linked to the evolution of life, because they provide a way to concentrate molecules into partially closed compartments. The dynamic shaping of cellular membranes is essential for many physiological processes, including cell morphogenesis, motility, cytokinesis, endocytosis, and secretion. It is therefore essential to understand the structure of the membrane and recognize the players that directly sculpt the membrane and enable it to adopt different shapes. The actin cytoskeleton provides the force to push eukaryotic plasma membrane in order to form different protrusions or/and invaginations. It has now became evident that actin directly co-operates with many membrane sculptors, including BAR domain proteins, in these important events. However, the molecular mechanisms behind BAR domain function and the differences between the members of this large protein family remain largely unresolved. In this thesis, the structure and functions of the I-BAR domain family members IRSp53 and MIM were thoroughly analyzed. By using several methods such as electron microscopy and systematic mutagenesis, we showed that these I-BAR domain proteins bind to PI(4,5)P2-rich membranes, generate negative membrane curvature and are involved in the formation of plasma membrane protrusions in cells e.g. filopodia. Importantly, we characterized a novel member of the BAR-domain superfamily which we named Pinkbar. We revealed that Pinkbar is specifically expressed in kidney and epithelial cells, and it localizes to Rab13-positive vesicles in intestinal epithelial cells. Remarkably, we learned that the I-BAR domain of Pinkbar does not generate membrane curvature but instead stabilizes planar membranes. Based on structural, mutagenesis and biochemical work we present a model for the mechanism of the novel membrane deforming activity of Pinkbar. Collectively, this work describes the mechanism by which I-BAR domain proteins deform membranes and provides new information about the biological roles of these proteins. Intriguingly, this work also gives evidence that significant functional plasticity exists within the I-BAR domain family. I-BAR proteins can either generate negative membrane curvature or stabilize planar membrane sheets, depending on the specific structural properties of their I-BAR domains. The results presented in this thesis expand our knowledge on membrane sculpting mechanisms and shows for the first time how flat membranes can be generated in cells.

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This thesis is concerned with the area of vector-valued Harmonic Analysis, where the central theme is to determine how results from classical Harmonic Analysis generalize to functions with values in an infinite dimensional Banach space. The work consists of three articles and an introduction. The first article studies the Rademacher maximal function that was originally defined by T. Hytönen, A. McIntosh and P. Portal in 2008 in order to prove a vector-valued version of Carleson's embedding theorem. The boundedness of the corresponding maximal operator on Lebesgue-(Bochner) -spaces defines the RMF-property of the range space. It is shown that the RMF-property is equivalent to a weak type inequality, which does not depend for instance on the integrability exponent, hence providing more flexibility for the RMF-property. The second article, which is written in collaboration with T. Hytönen, studies a vector-valued Carleson's embedding theorem with respect to filtrations. An earlier proof of the dyadic version assumed that the range space satisfies a certain geometric type condition, which this article shows to be also necessary. The third article deals with a vector-valued generalizations of tent spaces, originally defined by R. R. Coifman, Y. Meyer and E. M. Stein in the 80's, and concerns especially the ones related to square functions. A natural assumption on the range space is then the UMD-property. The main result is an atomic decomposition for tent spaces with integrability exponent one. In order to suit the stochastic integrals appearing in the vector-valued formulation, the proof is based on a geometric lemma for cones and differs essentially from the classical proof. Vector-valued tent spaces have also found applications in functional calculi for bisectorial operators. In the introduction these three themes come together when studying paraproduct operators for vector-valued functions. The Rademacher maximal function and Carleson's embedding theorem were applied already by Hytönen, McIntosh and Portal in order to prove boundedness for the dyadic paraproduct operator on Lebesgue-Bochner -spaces assuming that the range space satisfies both UMD- and RMF-properties. Whether UMD implies RMF is thus an interesting question. Tent spaces, on the other hand, provide a method to study continuous time paraproduct operators, although the RMF-property is not yet understood in the framework of tent spaces.

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An inverse problem for the wave equation is a mathematical formulation of the problem to convert measurements of sound waves to information about the wave speed governing the propagation of the waves. This doctoral thesis extends the theory on the inverse problems for the wave equation in cases with partial measurement data and also considers detection of discontinuous interfaces in the wave speed. A possible application of the theory is obstetric sonography in which ultrasound measurements are transformed into an image of the fetus in its mother's uterus. The wave speed inside the body can not be directly observed but sound waves can be produced outside the body and their echoes from the body can be recorded. The present work contains five research articles. In the first and the fifth articles we show that it is possible to determine the wave speed uniquely by using far apart sound sources and receivers. This extends a previously known result which requires the sound waves to be produced and recorded in the same place. Our result is motivated by a possible application to reflection seismology which seeks to create an image of the Earth s crust from recording of echoes stimulated for example by explosions. For this purpose, the receivers can not typically lie near the powerful sound sources. In the second article we present a sound source that allows us to recover many essential features of the wave speed from the echo produced by the source. Moreover, these features are known to determine the wave speed under certain geometric assumptions. Previously known results permitted the same features to be recovered only by sequential measurement of echoes produced by multiple different sources. The reduced number of measurements could increase the number possible applications of acoustic probing. In the third and fourth articles we develop an acoustic probing method to locate discontinuous interfaces in the wave speed. These interfaces typically correspond to interfaces between different materials and their locations are of interest in many applications. There are many previous approaches to this problem but none of them exploits sound sources varying freely in time. Our use of more variable sources could allow more robust implementation of the probing.