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  • Juslin, Niklas (Helsingin yliopisto, 2009)
    Fusion power is an appealing source of clean and abundant energy. The radiation resistance of reactor materials is one of the greatest obstacles on the path towards commercial fusion power. These materials are subject to a harsh radiation environment, and cannot fail mechanically or contaminate the fusion plasma. Moreover, for a power plant to be economically viable, the reactor materials must withstand long operation times, with little maintenance. The fusion reactor materials will contain hydrogen and helium, due to deposition from the plasma and nuclear reactions because of energetic neutron irradiation. The first wall divertor materials, carbon and tungsten in existing and planned test reactors, will be subject to intense bombardment of low energy deuterium and helium, which erodes and modifies the surface. All reactor materials, including the structural steel, will suffer irradiation of high energy neutrons, causing displacement cascade damage. Molecular dynamics simulation is a valuable tool for studying irradiation phenomena, such as surface bombardment and the onset of primary damage due to displacement cascades. The governing mechanisms are on the atomic level, and hence not easily studied experimentally. In order to model materials, interatomic potentials are needed to describe the interaction between the atoms. In this thesis, new interatomic potentials were developed for the tungsten-carbon-hydrogen system and for iron-helium and chromium-helium. Thus, the study of previously inaccessible systems was made possible, in particular the effect of H and He on radiation damage. The potentials were based on experimental and ab initio data from the literature, as well as density-functional theory calculations performed in this work. As a model for ferritic steel, iron-chromium with 10% Cr was studied. The difference between Fe and FeCr was shown to be negligible for threshold displacement energies. The properties of small He and He-vacancy clusters in Fe and FeCr were also investigated. The clusters were found to be more mobile and dissociate more rapidly than previously assumed, and the effect of Cr was small. The primary damage formed by displacement cascades was found to be heavily influenced by the presence of He, both in FeCr and W. Many important issues with fusion reactor materials remain poorly understood, and will require a huge effort by the international community. The development of potential models for new materials and the simulations performed in this thesis reveal many interesting features, but also serve as a platform for further studies.
  • Vörtler, Katharina (Helsingin yliopisto, 2011)
    Thermonuclear fusion is a sustainable energy solution, in which energy is produced using similar processes as in the sun. In this technology hydrogen isotopes are fused to gain energy and consequently to produce electricity. In a fusion reactor hydrogen isotopes are confined by magnetic fields as ionized gas, the plasma. Since the core plasma is millions of degrees hot, there are special needs for the plasma-facing materials. Moreover, in the plasma the fusion of hydrogen isotopes leads to the production of high energetic neutrons which sets demanding abilities for the structural materials of the reactor. This thesis investigates the irradiation response of materials to be used in future fusion reactors. Interactions of the plasma with the reactor wall leads to the removal of surface atoms, migration of them, and formation of co-deposited layers such as tungsten carbide. Sputtering of tungsten carbide and deuterium trapping in tungsten carbide was investigated in this thesis. As the second topic the primary interaction of the neutrons in the structural material steel was examined. As model materials for steel iron chromium and iron nickel were used. This study was performed theoretically by the means of computer simulations on the atomic level. In contrast to previous studies in the field, in which simulations were limited to pure elements, in this work more complex materials were used, i.e. they were multi-elemental including two or more atom species. The results of this thesis are in the microscale. One of the results is a catalogue of atom species, which were removed from tungsten carbide by the plasma. Another result is e.g. the atomic distributions of defects in iron chromium caused by the energetic neutrons. These microscopic results are used in data bases for multiscale modelling of fusion reactor materials, which has the aim to explain the macroscopic degradation in the materials. This thesis is therefore a relevant contribution to investigate the connection of microscopic and macroscopic radiation effects, which is one objective in fusion reactor materials research.
  • Mononen, Tommi (Helsingin yliopisto, 2009)
    Minimum Description Length (MDL) is an information-theoretic principle that can be used for model selection and other statistical inference tasks. There are various ways to use the principle in practice. One theoretically valid way is to use the normalized maximum likelihood (NML) criterion. Due to computational difficulties, this approach has not been used very often. This thesis presents efficient floating-point algorithms that make it possible to compute the NML for multinomial, Naive Bayes and Bayesian forest models. None of the presented algorithms rely on asymptotic analysis and with the first two model classes we also discuss how to compute exact rational number solutions.
  • Björkroth, Johanna (1990)
    Työn tarkoituksena oli selvittää concanavalin A -pikatestin(Ani Biotech) soveltuvuutta koiran akuutin tulehdusvasteen mittaamiseen. Tutkimuksessa testattiin kahdessa osassa yhteensä sadan neljän koiran seeruminäytteet, joista kolmekymmentäviisi näytettä oli terveistä yksilöistä. Pitämällä neutrofiliaa akuutin tulehdusvasteen ilmaisijana saatiin testin sensitiivisyydeksi 94,4 % ja spesifisyydeksi 83,7 %. Akuutin tulehdusvasteen ilmaisijana testi vaikuttaa toimivan hyvin. Käytännössä olisi ehkä mahdollista soveltaa tätä pyometran diagnosoinnissa ja erityisesti pyometran ja endometriitin erottelussa.
  • Huuskonen, Arto (MTT, 2009)
    The first aim of this thesis was to produce data for evaluating, developing and recommending biologically and economically efficient energy and protein feeding strategies for growing and finishing dairy bulls offered grass silage-based diets. The second aim was to calculate the energy and protein supplies of the dairy bulls fed different grass silage-cereal-based diets and, based on this, to estimate the possible need to revise the current Finnish energy and protein recommendations for growing dairy bulls. The third aim was to demonstrate the phosphorus supply of dairy bulls fed grass silage-cereal-based diets with or without protein supplementation in relation to current feeding recommendations for phosphorus. The results indicate that protein supplement is not needed for finishing dairy bulls (live weight more than 250 kg) when they are fed good-quality grass silage (digestible organic matter more than 650 g/kg dry matter, restricted fermentation with low concentrations of fermentation acids and ammonia N) and grain-based concentrate with a moderate (300-700 g/kg dry matter) concentrate level. The results also suggest that with total mixed ration feeding it is possible to use rather high concentrate proportions (700 g/kg dry matter) in feeding dairy bulls. According to this study, barley fibre is a suitable energy supplement with good-quality silage for growing dairy bulls. The results suggest that 50% of barley grain can be replaced with barley fibre without affecting growth. Also oats is a suitable energy supplement for dairy bulls. However, as a consequence of decreased energy intake, the gain and feed conversion of the bulls were slightly reduced in this study when barley grain was replaced by oats in the diet. Ultimately, the rationality of the use of barley fibre and oats in the future will depend on the price in relation to other concentrates. During the feeding experiments the calculated supply of energy was 10% higher than in the Finnish feeding recommendations for the present growth rate. This indicates that there is a need to update the Finnish feeding recommendations for dairy-breed growing bulls, and further calculations are needed for the energy supply of growing dairy bulls. The calculated supply of AAT (amino acids absorbed from the small intestine) was 38% higher than in the Finnish feeding recommendations for the present growth. Possibly, the present AAT-PBV system is not an optimal protein evaluation system for growing dairy bulls more than 250 kg live weight. The calculations based on the feeding experiments and the Finnish feeding recommendations indicate that in most cases the dairy bulls (live weight more than 250 kg) received enough P from the basic grass silage cereal-based diets without additional mineral feeds. Therefore there is no need to add P in the form of mineral mixtures.
  • Pokharel, Pramod (2014)
    An aerosol is a colloid of fine solid particles or liquid droplet, in air or another gas (Hinds, 1999).The total carbon (TC) in carbonaceous aerosols can be divided into Inorganic Carbon (IC), Organic Carbon (OC) and Elemental Carbon (EC).We measured carbonaceous aerosols at theSMEAR II (Station for measuring ecosystem atmosphere relations) in southern Finland based on division of Atmospheric Sciences of University of Helsinki. The measurements were carried out continuously from 2005 using different instruments. We used a thermal-optical method to analyze carbonaceous aerosols at Hyytiälä and examineddiurnal and seasonal variation in EC, OC, TC, OC/EC ratio, black carbon (BC) and organics. We found the mean concentrations of EC and OC estimated using Sunset Lab. OCEC analyzer and BC measured using Magee scientific Aethalometer were 0.22±0.19 µgC/m3, 1.53±0.92µgC/m3 and 0.35±0.30 µg/m3 respectively. Whereas the average concentration of BC measured using MAAP was 0.2±0.2 µg/m3. We also found concentrations of EC and BC to be low in summer and high in winter, whereas, the opposite was true for OC. EC, OC and BC showed no significant diurnal cycle, but clear seasonal cycle in all carbonaceous aerosols was evident. The aerosols mass measured by aerosolmass spectrometer (AMS) showed 58% organics, 28% sulfates, 5% nitrates, 9% ammonium and less than 1% chlorides at Hyytiälä.The primary organic carbon (POC) and secondary organic carbon (SOC) estimated by EC-tracer method contributed 5% and 95% respectively to the OC concentrations at Hyytiälä. The relations between different measurement instruments showed a good agreement.
  • Pesonen, Petteri (Helsingin yliopisto, 2002)
    Tutkielma käsittelee nykyisiä kognitiotieteen teorioita käsitteistä ja niiden mallintamista oliokeskeisillä tietämyksen esittämisen menetelmillä. Käsiteteorioista käsitellään klassinen, määritelmäteoria, prototyyppiteoria, duaaliteoriat, uusklassinen teoria, teoria-teoria ja atomistinen teoria. Oliokeskeiset menetelmät ovat viime aikoina jakautuneet kahden tyyppisiin kieliin: oliopohjaisiin ja luokkapohjaisiin. Uudet olio-pohjaiset olio-ohjelmointikielet antavat käsitteiden representointiin mahdollisuuksia, jotka puuttuvat aikaisemmista luokka-pohjaisista kielistä ja myös kehysmenetelmistä. Tutkielma osoittaa, että oliopohjaisten kielten uudet piirteet tarjoavat keinoja, joilla käsitteitä voidaan esittää symbolisessa muodossa paremmin kuin perinteisillä menetelmillä. Niillä pystytään simuloimaan kaikkea mitä luokkapohjaisilla kielillä voidaan, mutta ne pystyvät lisäksi simuloimaan perheyhtäläisyyskäsitteitä ja mahdollistavat olioiden dynaamisen muuttamisen ilman, että siinä rikotaan psykologisen essentialismin periaatetta. Tutkielma osoittaa lisäksi vakavia puutteitta, jotka koskevat koko oliokeskeistä menetelmää. Avainsanat: käsitteet, käsiteteoriat, tekoäly, komputationaalinen psykologia, olio-ohjelmointi, tiedon esittäminen
  • Stodolsky, Venla (2008)
    The master’s research presented here is an empirical study based on qualitative methods. The purpose of this thesis is to produce a deeper understanding of the concepts of democracy as viewed by the student elites in Shanghai, China and St.Petersburg, Russia. The thesis is a comparative study, i.e. it scrutinizes the western democracy theories and compares them to the Russian and Chinese student’s ideas on the concepts of democracy. The idea is to find out what the future leaders, who at the moment are university students, concepts of democracy are. The thesis is based on two sets of interviews of university students in China and Russia. The thesis aims to answer to a question whether the concepts of democracy viewed by the Chinese and Russian students are the same as the western concepts of democracy. The hypothesis is that there are signs of “western democracy” in China and in Russia. The main theoretical framework for this study is the four different democratic theorists’, i.e. Robert Dahl’s, David Held’s, Seymour Lipset’s and Heikki Patomäki’s theories on democracy. Their democracy concepts are examined and compared to the findings arising out of the interviewed Chinese and Russian students’ democracy concepts. The main qualitative methods used in this study are based on Eeva Pyörälä’s six factors as outlined in her article “Kvalitatiivisen tutkimuksen metodologiaa” in Laadullisen tutkimuksen risteysasemalla. The thesis has been divided into seven parts. After the introduction in chapter one, the theoretical framework, research strategy, methodology and sources are examined in the second chapter. In the third chapter the four different democracy theorist’s concepts of democracy are explained and set against the results of the interviews. The chapter four briefly introduces the histories, cultures and traditions connected to democracy in China and Russia. The fifth and sixth chapters are devoted to the analyzing of the interviews related to the four theories of this study. Chapter five also introduces the questionnaire design, selection of interviewees and explanations on the field work and peculiarities of the interviews. The sixth chapter binds the empirical material into the theoretical conceptions. The Atlas software programme tool utilized to analyze the interviews is described and the actual interviews are analyzed. The conclusion in the seventh chapter summarizes the conceptual understanding of the interviewees and comparison to western theories. The findings of this study suggest that the western theories as such do not correspond to the Chinese or Russian students’ views on the concepts of democracy.
  • Lindén, Andreas (Helsingin yliopisto, 2010)
    Population dynamics are generally viewed as the result of intrinsic (purely density dependent) and extrinsic (environmental) processes. Both components, and potential interactions between those two, have to be modelled in order to understand and predict dynamics of natural populations; a topic that is of great importance in population management and conservation. This thesis focuses on modelling environmental effects in population dynamics and how effects of potentially relevant environmental variables can be statistically identified and quantified from time series data. Chapter I presents some useful models of multiplicative environmental effects for unstructured density dependent populations. The presented models can be written as standard multiple regression models that are easy to fit to data. Chapters II IV constitute empirical studies that statistically model environmental effects on population dynamics of several migratory bird species with different life history characteristics and migration strategies. In Chapter II, spruce cone crops are found to have a strong positive effect on the population growth of the great spotted woodpecker (Dendrocopos major), while cone crops of pine another important food resource for the species do not effectively explain population growth. The study compares rate- and ratio-dependent effects of cone availability, using state-space models that distinguish between process and observation error in the time series data. Chapter III shows how drought, in combination with settling behaviour during migration, produces asymmetric spatially synchronous patterns of population dynamics in North American ducks (genus Anas). Chapter IV investigates the dynamics of a Finnish population of skylark (Alauda arvensis), and point out effects of rainfall and habitat quality on population growth. Because the skylark time series and some of the environmental variables included show strong positive autocorrelation, the statistical significances are calculated using a Monte Carlo method, where random autocorrelated time series are generated. Chapter V is a simulation-based study, showing that ignoring observation error in analyses of population time series data can bias the estimated effects and measures of uncertainty, if the environmental variables are autocorrelated. It is concluded that the use of state-space models is an effective way to reach more accurate results. In summary, there are several biological assumptions and methodological issues that can affect the inferential outcome when estimating environmental effects from time series data, and that therefore need special attention. The functional form of the environmental effects and potential interactions between environment and population density are important to deal with. Other issues that should be considered are assumptions about density dependent regulation, modelling potential observation error, and when needed, accounting for spatial and/or temporal autocorrelation.
  • Gorchakova, Nadezda (2012)
    The purpose of this thesis is to explore the economic dimension of transnational engagement of the Somali diaspora living in Finland. It is suggested that the social aspect of transnational economic engagement constitutes a major force in creating and reproducing remittance practices as well as the internal diaspora structures. Another objective of this study was to show how the theory of social capital can be effectively utilized in the studies of transnational economic activities. Accordingly, the view of remittances as an act of investment in social networks, which, as a value-laden action, facilitates the perpetual process of social capital (re)production is proposed. It is further argued that social class should be considered in conjunction with gender and ethnicity as factors that lie at the centre of the cycle of capital reproduction. The empirical data was collected by means of semi-structured interviews. The target group can be described as educated and well integrated into the Finnish labour market Somalis that are living in Helsinki and its surrounding areas. With the purpose of enhancing the empirical analysis, two expert interviews were conducted. Both information in printed and online media and the snowballing method were used in order to draw the participants for this study. The research findings revealed how transnational diaspora ties are articulated and enacted in the view of social capital (re)production and remittance practices. The politicized issue of transnational diasporic activities constitute one of the dimensions that shape the way how the subjects in this research relate to diasporic social networks. The perceived dominant role of Somali women in managing transnational support systems called attention to the gendered aspect of social capital. Interestingly, the widespread perception of the scale of women’s participation in remittance practices runs contrary to the existing statistics. Another crucial observation was that not all social ties are ‘mobilisable’, or can be draw upon at any time. In conclusion, it is advocated that more in-depth research on the gender aspect of remittance practices as well as on the nature of the differences between refugee and labour remittances, particularly in terms of social relations that determine them, could significantly enhance the understanding of the topic in question.
  • Kaatrakoski, Heli (Helsingin yliopisto, 2016)
    In the public sector, an emphasis on a customer approach has spread to a number of fields of work in Finland. This thesis investigates the conveyance and development of the concept of customer in four Finnish public organisations. The point of departure for the study is the marketisation of the public sector and the New Public Management (NPM) ideology, which emphasise the benefits of business models in public sector practices. The introduction of the concept of customer is an example of such benefits, and the development of the concept is examined in this particular cultural and historical context. Previous international studies have raised challenges related to customer thinking in the public sector and concerns over official discourses that seem to simplify the fundamental societal implications produced by the customer approach. The theoretical framework of my study is cultural-historical activity theory. The data comprises interviews (53) and documents (42) from each organisation. The studied organisations represent fields of elderly care, children s day care, road management, and academic library work. The findings in the document analysis suggest that in all the studied organisations, the use of the concept of customer has increased along with the introduction of the NPM doctrine. One interesting finding is the variety of conflicting situations which the interviewees experienced regularly in their service encounters. These conflicting situations are related to dominating old organisational structures and practices, which have not developed sufficiently with regard to customer thinking. In addition to these conflicting situations, another interesting finding was shared discourses which were related to the customer approach. My interpretation in this study is that at the core of the concept of the public sector customer are the opposing forces of the private sector s understanding of human beings as responsible individuals with free choice and the public sector s emphasis on collective citizenship and the public good. The opposing forces produce not only a variety of conflicting situations, but also possibilities for the development of the concept. This thesis theoretically opens up the background ideology behind the concept of customer in the public sector and thus increases the understanding of larger ongoing societal changes. The study provides new openings in regard to empirical studies on customer thinking from the perspective of employees. Such research objectives have been limited in number in the Finnish context. One important contribution of this study in regard to studies of working life is its explanation of the origin of conflicting situations from systemic tensions instead of trying to trace their origins to the behaviour of individuals.
  • Huttula, Samuli (Helsingfors universitet, 2015)
    Lainsäädäntötoimenpiteet sosiaalisten perusoikeuksien kuten lakko-oikeuden ja järjestäytymisoikeuden osalta eivät lähtökohtaisesti kuulu EU:n toimivaltaan. Siitä huolimatta Euroopan unionin tuomioistuimen viimeaikaiset ratkaisut asioissa Viking, Laval ja Rüffert ovat luoneet oman haasteensa sosiaalisten perusoikeuksien ja markkinavapauksien tasapainottamiselle. Näissä tapauksissa EUT tulkitsi sosiaalisten perusoikeuksien rajoittavan perusvapauksia, jota ei voitu pitää EU-oikeuden kannalta hyväksyttävänä vaikka esimerkiksi lakko-oikeudesta säätäminen kuuluu jäsenvaltioiden yksinomaiseen toimivaltaan. Tutkielma pyrkii vastaamaan siihen, kuinka lakko-oikeus osana järjestäytymisoikeutta tulisi ymmärtää ja määritellä oikeudellisena käsitteenä Eurooppalaisessa kontekstissa. Tarkoituksena on käsitteellistää lakko-oikeuteen liittyvää problematiikkaa sekä kansallisesta että EU-tason näkökulmasta ja peilata sitä EUT:n tulkintakäytäntöön ja jäsenvaltioiden kansainvälisiin velvoitteisiin. Arvion kohteena on myös se, kuinka EU-oikeuden lainvalintasäännöt vaikuttavat lakko-oikeuden harjoittamiseen unionin alueella. Tässä suhteessa perehdytään erityisesti Rooma II asetuksen 9 artiklaan. Tutkimuksen metodi on lainopillinen eli tutkimus tulkitsee ja systematisoi tietyn oikeudellisen käsitteen muodostamista. Tätä tavoitetta täydennetään hyödyntäen oikeusvertailevaa pohdintaa erityisesti jäsenvaltioiden työmarkkinajärjestelmien osalta. Lisäksi tutkimuksen viitekehyksessä pyritään tunnistamaan EU:lle ominaiseen hajautuneeseen kansainvälisyksityisoikeudelleen sääntelyyn liittyviä ongelmia metodologisesta näkökulmasta ja esittämään perustuslaillisen ulottuvuuden omaaville normikonflikteille ns. lävistävä (diagonal) käsitteellistämistapa. Keskeisimpänä tuloksena tutkielmassa esitetään jäsenvaltioiden suhtautumisen järjestäytymisvapauteen ja lakko-oikeuteen olevan hyvin monimuotoista. Lainvalintanormeilla voi olla rajoittavaa vaikutusta lakko-oikeuden harjoittamiseen rajat ylittävissä työtaistelutoimenpiteissä. EUT:n tulkintakäytännöllä on hyvin erilaisia vaikutuksia eri jäsenvaltioissa riippuen siitä, miten työmarkkinat on järjestetty. Kokoavasti voidaan kuitenkin todeta, että tietyissä maissa vaikutukset ovat hyvin perustavanlaatuisia ja usein ristiriidassa jäsenvaltioiden kansainvälisten velvoitteiden kanssa. Tähän liittyen huomioidaan myös se, että EUT ei ole luonteeltaan ylikansallinen perustuslakituomioistuin, minkä vuoksi viimeaikainen kehitys ja sen tarkoituksenmukaisuus voidaan kyseenalaistaa.
  • Rantanen, Mika (Helsingin yliopisto, 2010)
    Concordia-lehti alkaessaan ilmestyä 1994 herätti ristiriitaisia reaktioita esimerkiksi SLEY:n henkilöstön keskuudessa. Alusta alkaen avainhenkilöitä ovat olleet Hannu Lehtonen, Hannu Halonen, Simo Kiviranta ja Sakari Korpinen. Ekumeniaan Concordia on suhtautunut kriittisesti arvioidessaan Porvoon sopimusta ja Yhteistä julistusta vanhurskauttamisesta. Keskeisiä teemoja tässä lehdessä ovat olleet tutkittavana aikana yleinen ja uskon kautta tapahtuva vanhurskauttaminen, Raamatun arvovallan korostaminen, sakramenttien merkityksen esillä pitäminen ja tietyt moraaliset ja eettiset periaatteet ja näkökulmat. Concordiassa on esiintynyt runsaasti sitaatteja Martti Lutherin teoksista, melko paljon myös luterilaisen ortodoksian edustajilta, kuten Martin Chemnitziltä ja Johann Gerhardilta. Ylivoimaisesti eniten artikkeleja kymmenen vuoden aikana on tehnyt päätoimittaja, pastori Hannu Lehtonen. Kirjoittajien joukossa maallikkojen osuus on ollut huomattava. Karismaattisia ilmiöitä arvioitaessa nähtiin osan armolahjoista kuuluneen ennen kaikkea alkukirkon aikaan, vaikka samalla todettiin ihmeitä voivan tapahtua nykyaikanakin. Concordian kirjoittajat eivät hyväksyneet läheskään kaikkia Suomen evankelis-luterilaisessa kirkossa tapahtuneita päätöksiä, asioita ja ilmiöitä. Voimakkaasti todettiin, että kirkossa ei tulisi samanaikaisesti sallia sekä totuutta että erilaisia harhaoppeja. Myös evankelisen liikkeen tai muiden herätysliikkeiden toimintaa ei aina pidetty tarpeeksi rohkeana, vaan katsottiin niiden mukautuneen liikaa yhteiskuntaan ja yleiseen ja valtaa pitävään kirkollisuuteen. Esimerkiksi Helsingin yliopistossa käytettyä historiallis-kriittistä metodia parempana metodina pidettiin historiallis-dogmaattista. Opetusta maailman syntymisestä pitkän evoluutio-prosessin seurauksena ei Concordiassa hyväksytty, vaan opetettiin Jumalan luoneen maailman kuudessa päivässä. Concordiassa kirjoittajina on esiintynyt myös useita tunnustuksellisen luterilaisuuden edustajia lähinnä Yhdysvalloista ja Pohjoismaista. Tutkitun lehden merkitys kirkollisessa kentässä ei ole tilaajamäärän pienuuden vuoksi kovin merkittävä, mutta eräänlaisena taustalla vaikuttajana ja keskustelun herättäjänä vaikutus on ollut suurempi. Concordian näkemyksen mukaan suuri enemmistö ei läheskään aina ole ollut oikeassa hengellisissä kysymyksissä. Evankeliseen liikkeeseen Concordian kirjoittajilla on ollut tietynlainen viha-rakkaussuhde, vaikka se on ollut monen kirjoittajan hengellinen koti. Lehdessä esiintynyttä pietismin arviointia tutkimus ei ole kovin paljon käsitellyt, koska se ei olisi kovin hyvin sopinut eri lukujen otsi- koiden alle. Helluntailaisuuden eri opinkäsityksiä Concordia on myös pyrkinyt kumoamaan. Lehti on halunnut koko ajan perustella opetuksensa selkeillä raamatunkohdilla ja edistää näin luterilaisen uskon ja opin tuntemusta. Tässä tutkimuksessa on ollut tietoinen valinta käyttää samoja raamatunkohtia lähteenä, joita Concordian kirjoittajat ovat itse käyttäneet. Kirkkohistoriaan kuuluvassa opinnäytteessä ei ole yleensä tyypillistä käyttää näin paljon viittauksia Raamattuun, mutta tällainen dogmatiikan mukaan ottaminen on perusteltua, koska se on niin olennainen osa Concordia-lehden teologiaa ja tapaa tuoda esille asioita. Tiivistetysti todeten ihmisten ainoa vapahtaja ja pelastaja on ollut tutkitun lehden mukaan ja on edelleen Jeesus Kristus.
  • Haavisto, Camilla (Helsingin yliopisto, 2011)
    This study deals with how ethnic minorities and immigrants are portrayed in the Finnish print media. The study also asks how media users of various ethnocultural backgrounds make sense of these mediated stories. A more general objective is to elucidate negotiations of belonging and positioning practices in an increasingly complex society. The empirical part of the study is based on content analysis and qualitative close reading of 1,782 articles in five newspapers (Hufvudstadsbladet, Vasabladet, Helsingin Sanomat, Iltalehti and Ilta-Sanomat) during various research periods between 1999 and 2007. Four case studies on print media content are followed up by a focus group study involving 33 newspaper readers of Bosnian, Somalian, Russian, and 'native' Finnish backgrounds. The study draws from different academic and intellectual traditions; mainly media and communication studies, sociology and social psychology. The main theoretical framework employed is positioning theory, as developed by Rom Harré and others. Building on this perspective, situational self-positioning, positioning by others, and media positioning are seen as central practices in the negotiation of belonging. In support of contemporary developments in social sciences, some of these negotiations are seen as occurring in a network type of communicative space. In this space, the media form one of the most powerful institutions in constructing, distributing and legitimising values and ideas of who belongs to 'us', and who does not. The notion of positioning always involves an exclusionary potential. This thesis joins scholars who assert that in order to understand inclusionary and exclusionary mechanisms, the theoretical starting point must be a recognition of a decent and non-humiliating society. When key insights are distilled from the five empirical cases and related to the main theories, one of the major arguments put forward is that the media were first and foremost concerned with a minority actor's rightful or unlawful belonging to the Finnish welfare system. However, in some cases persistent stereotypes concerning some immigrant groups' motivation to work, pay taxes and therefore contribute are so strong that a general idea of individualism is forgotten in favour of racialised and stagnated views. Discussants of immigrant background also claim that the positions provided for minority actors in the media are not easy to identify with; categories are too narrow, journalists are biased, the reporting is simplifying and carries labelling potential. Hence, although the will for the communicative space to be more diverse and inclusive exists — and has also in many cases been articulated in charters, acts and codes — the positioning of ethnic minorities and immigrants differs significantly from the ideal.
  • Siukosaari, Päivi (Helsingin yliopisto, 2013)
    This study is part of the longitudinal population based Helsinki Aging Study (HAS). The study population consisted of a random sample of subjects born in 1904, 1909 and 1914 and living in Helsinki, Finland in 1990. Clinical oral and radiographical status along with an interview on background factors, oral health behavior and self-perceived need of treatment were obtained from 364 elderly aged 76, 81 and 86 years at the baseline in 1990-91. Of these 196 were dentate and the 171 dentate who had information on their education formed the baseline study group. Prior to oral examination the participants underwent comprehensive medical examination. Five years later 113 dentate elderly participated in the follow-up examinations. Background information for the non-participation analysis was obtained from the medical HAS records. To assess any possible non-response bias we evaluated the background factors of the participants and non-participants. The multicausal analysis revealed that the strongest factors explaining non-participation were old age (OR=3.6), being edentulous (OR=2.5), having clinically diagnosed signs of dementia (OR=4.1) and a deteriorated ability to move easily (OR=5.3). Caries was common among the participants. At baseline 71% of men and 48% of women had decayed teeth. Subjects DMFT (Decayed Missing Filled Teeth) index increased during the follow-up mostly as a result of tooth extractions. Although the number of teeth and root surfaces (p PIENEMPI 0.05) at risk were higher in the high education groups, no significant differences were found in number of DRS (Decayed Root Surfaces) (0.6 ± 1.3) and RCI (Root Caries Index) (0.13 ± 0.18) in the different education groups. The only factor, which could explain the increment in root caries, was high salivary microbial counts. However, none of the salivary factors examined were directly associated with the level of education. Many of these participants were also in need of periodontal treatment. The results of the study indicated that there are oral health disparities among this elderly population. The fact that the elderly with higher level of education had more remaining teeth than the elderly with lower level of education explained the finding that better educated elderly also had a greater need for periodontal treatment. During the five year follow-up only slight deteriorating in periodontal health was found, while the differences between education groups remained, indicating that good periodontal health is possible to maintain even with advancing age. The major chronic oral diseases, caries and periodontal disease, share many common risk factors. While there is much evidence on the prevention of these diseases, the implementation of this knowledge into successful programs for specific groups and populations has been modest. This was also seen in the present study population with high prevalence of caries and periodontal diseases. There is an urgent need for preventive programs against caries and periodontal disease both in the community and individual level because a growing proportion of older adults retain their teeth into old age and the proportion of the older adults in the population is estimated to continue to grow.
  • Konttinen, Anu (Helsingin yliopisto, 2008)
    Anu Konttinen: Conducting Gestures Institutional and Educational Construction of Conductorship in Finland, 1973-1993. This doctoral thesis concentrates on those Finnish conductors who have participated in Professor Jorma Panula s conducting class at the Sibelius Academy during the years 1973 1993. The starting point was conducting as a myth, and the goal has been to find its practical opposite the practical core of the profession. What has been studied is whether one can theorise and analyse this core, and how. The theoretical goal has been to find out what kind of social construction conductorship is as a historical, sociological and practical phenomenon. In practical terms, this means taking the historical and social concept of a great conductor apart to look for the practical core gestural communication. The most important theoretical tool is the concept of gesture. The idea has been to sketch a theoretical model based on gestural communication between a conductor and an orchestra, and to give one example of the many possible ways of studying the gestures of a conductor.
  • Suomalainen, Anni (Helsingin yliopisto, 2010)
    In dentistry, basic imaging techniques such as intraoral and panoramic radiography are in most cases the only imaging techniques required for the detection of pathology. Conventional intraoral radiographs provide images with sufficient information for most dental radiographic needs. Panoramic radiography produces a single image of both jaws, giving an excellent overview of oral hard tissues. Regardless of the technique, plain radiography has only a limited capability in the evaluation of three-dimensional (3D) relationships. Technological advances in radiological imaging have moved from two-dimensional (2D) projection radiography towards digital, 3D and interactive imaging applications. This has been achieved first by the use of conventional computed tomography (CT) and more recently by cone beam CT (CBCT). CBCT is a radiographic imaging method that allows accurate 3D imaging of hard tissues. CBCT has been used for dental and maxillofacial imaging for more than ten years and its availability and use are increasing continuously. However, at present, only best practice guidelines are available for its use, and the need for evidence-based guidelines on the use of CBCT in dentistry is widely recognized. We evaluated (i) retrospectively the use of CBCT in a dental practice, (ii) the accuracy and reproducibility of pre-implant linear measurements in CBCT and multislice CT (MSCT) in a cadaver study, (iii) prospectively the clinical reliability of CBCT as a preoperative imaging method for complicated impacted lower third molars, and (iv) the tissue and effective radiation doses and image quality of dental CBCT scanners in comparison with MSCT scanners in a phantom study. Using CBCT, subjective identification of anatomy and pathology relevant in dental practice can be readily achieved, but dental restorations may cause disturbing artefacts. CBCT examination offered additional radiographic information when compared with intraoral and panoramic radiographs. In terms of the accuracy and reliability of linear measurements in the posterior mandible, CBCT is comparable to MSCT. CBCT is a reliable means of determining the location of the inferior alveolar canal and its relationship to the roots of the lower third molar. CBCT scanners provided adequate image quality for dental and maxillofacial imaging while delivering considerably smaller effective doses to the patient than MSCT. The observed variations in patient dose and image quality emphasize the importance of optimizing the imaging parameters in both CBCT and MSCT.
  • Kinnunen, Hanna (1930)