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  • Piltti, Katja (Helsingin yliopisto, 2009)
    Stem cells are responsible for tissue turnover throughout lifespan. Only highly controlled specific environment, the stem cell niche , can sustain undifferentiated stem cell-pool. The balance between maintenance and differentiation is crucial for individual s health: uncontrolled stem cell self-renewal or proliferation can lead to hyperplasia and mutations that further provoke malignant transformation of the cells. On the other hand, uninhibited differentiation may result in diminished stem cell population, which is unable to maintain tissue turnover. The mechanisms that control the switch from maintenance to differentiation in stem cells are not well known. The same mechanisms that direct the self-renewal and proliferation in normal stem cells are likely to be also involved in maintenance of cancer stem cell . Cancer stem cells exhibit stem cell like properties such as self-renewal- and differentiation capacity and they can also regenerate the tumor tissue. In this thesis, I have investigated the effect of classical oncogenes E6/E7 and c-Myc, tumor suppressors p53 and retinoblastoma (pRb) family, and vascular endothelial growth factor (VEGF) subfamily and glial cell line-derived neurothropic factor (GDNF) family ligands on behavior of embryonic neural stem cells (NSCs) and progenitors. The study includes also the characterization of cytoskeletal tumor suppressor neurofibromatosis 2 (NF2) protein merlin and ezrin-radixin-moesin (ERM) protein ezrin expression in neural progenitors cells and their progeny. This study reveals some potential mechanisms regarding to NSCs maintenance. In summary, the studied molecules are able to shift the balance either towards stem cell maintenance or differentiation; tumor suppressor p53 represses whereas E6/E7 oncogenes and c-Myc increase the proportion of self-renewing and proliferating NSCs or progenitors. The data suggests that active MEK-ERK signaling is critical for self-renewal of normal and oncogene expressing NSCs. In addition, the results indicate that expression of cytoskeletal tumor suppressor merlin and ERM protein ezrin in central nervous system (CNS) tissue and progenitors indicates their role in cell differentiation. Furthermore, the data suggests that VEGF-C a factor involved in lymphatic system development, angiogenesis, neovascularization and metastasis but also in maintenance of some neural populations in brain is a novel thropic factor for progenitors in early sympathetic nervous system (SNS). It seems that VEGF-C dose dependently through ERK-pathway supports the proliferation and survival of early sympathetic progenitor cells, and the effect is comparable to that of GDNF family ligands.
  • Isoaho, Eemeli (2016)
    The 2015 World Summit Outcome Document underlined the fundamental role of sovereign states as protectors of their citizens from genocide, war crimes, crimes against humanity, and ethnic cleansing, but it further stressed that should a state fail to protect its citizens from such atrocities, the international community would have a responsibility to intervene. As the first UN document to explicitly declare that states would no longer be safe from foreign interference solely on the principle of sovereignty, the Outcome Document’s formulation of the emerging concept of “responsibility to protect” was unprecedented. In seeking to study the implementation of the responsibility to protect principle in the context of the African Union, this study analyses how the Union has conceptualized sovereignty vis-à-vis humanitarian interventions. The theoretical framework of study is built on two opposing notions of sovereignty a pluralist, state-centered sovereignty akin to traditional Westphalian sovereignty, which considers all states equal in their protection from foreign intervention, and a solidarist notion of sovereignty that prioritizes the protection of civilians against mass atrocities over the protection of states against foreign interference. The discussion of the study’s main findings draws on theories of political realism. The research analyses 346 communiqués issued by the Peace and Security Council of the African Union between 2004 and 2014 to ascertain whether the Union maintains a pluralist or a solidarist understanding of sovereignty. The method of analysis builds on content analysis and combines both quantitative and qualitative analysis. The analysis suggests a twofold argument. On the one hand, the AU PSC maintains a state-centered, pluralist understanding of sovereignty. The Peace and Security council categorically links sovereignty to the territorial integrity of member states, thereby conceptualizing sovereignty in the context of bordered nation-states. It also strongly rejects foreign humanitarian interventions and issues sanctions to primarily to protect states, not civilians. On the other hand, the findings suggest that the African Union is slowly moving towards a more solidarist notion of sovereignty that prioritizes civilian protection. Although most calls for sanctions relate sanctions to the protection of the state, since 2012 the AU PSC has increasingly called for sanctions on humanitarian grounds. The Peace and Security Council has also opened up its traditionally closed deliberations for engagement with civil society actors in open sessions on themes closely related to the protection of civilians. An analysis of the findings suggests that the African Union suffers from severe lack of financial self-sufficiency, which undermines its neutrality but also its ability to react rapidly to emerging crises. Moreover, the notion of subsidiarity and seeking African solutions to African problems are prevalent in the Union’s policy discussions, which contribute to rendering it more likely to oppose non-African interventions in its member states. A theoretical discussion of these findings from the perspective of political realism further points to growing economic interdependence and transnationalization of African crises as factors that might explain the African Union’s shift towards solidarist sovereignty.
  • Ronkainen, Katariina (2014)
    The term 'Third World women' has its connotations back in the history reflecting both the juxtaposition of developed and developing world, and the dichotomy based on sex. It is still a widely used concept in current everyday life. The women of developing countries are portrayed under one category as Third World women in news, journalism and textbooks. As a term Third World women is understood in context of certain geographical locations and stagnant representations of people. In core are also their victim roles in relation for example to religion, culture or men. The aim of this master's thesis is to examine representations of the Third World women in Finnish development journal. Temporal changes in representations are discovered by observing the forty-year long publishing history of Kehitys -journal (former Kehitysyhteistyö). The main premise of this thesis is the idea of social constructionism. In social constructionism actions and thoughts are seen creating the social reality and language used both reflecting and creating it. The thesis questions media's representational power to name, illustrate and portray women in developing countries. This is done by utilizing theories of feminism, postcolonialism and development studies. Caroline Moser's and Janet Momsen's listings about the policy approaches on Third World women can be held as the frame work of this thesis. They have categorized global trends in development discourses relating to women. By comparing these approaches, trends in feminist and development theories, with the Finnish development journals, linkages between context and place specific representations of the Third World were found. Even though Finnish trends in Third World women's representations were less varying, still universal relations were able to be discovered. By conducting critical discourse analysis and content analysis of the women related articles in Kehitysyhteistyö and Kehitys -journals during the publications period from 1969 to 2009, it was possible to find five different kinds of discourses: women in development discourse, welfare discourse, efficiency discourse, misery discourse and life story discourse. Within these discourses main changes were in the ways to write and position women. Changes occurred for example in the themes relating to women and in their subjective narration. During forty years, the representations of the Third World women have changed back and forth, but it seems that the current trend in development journalism in Finland is highlighting the subjectivity and expertise of women. Women's own interests and thoughts are getting more exposure and the representational top-down dictation is decreasing while giving the floor to personal depictions.
  • Pensola, Tiina (2003)
    Social class differences in mortality are larger in middle adulthood than at any other time of life. Circumstances over the lifecourse may contribute to these adult social class differences. However, it is only rarely that the lifecourse approach has been applied to mortality studies among persons in their middle adulthood. The aim of this thesis is to disentangle the effects of the living conditions in the parental home and major transition in youth on social class differences in mortality from various causes of death among women and men aged 31-42 at death, and to evaluate whether the effect of the past circumstances on mortality is through latency, accumulation or pathway mechanisms. This thesis (papers II-V) is based on the 1990 census data for all Finnish persons born in 1956-60 linked with death records (4369 deaths) for 1991-98 and with information on lifecourse circumstances from the 1970, 1975, 1980 and 1985 censuses. These aggregated cross-tables are analysed by means of Poisson regression. Parental home had an association with disease mortality from age 20 onwards, indicating a latency effect. However, the direct effect of the parental home on mortality was minor, and therefore the contribution of latency model to differential mortality remained small. An indication for the accumulative effect of disadvantageous social class was found for cardiovascular diseases and alcohol-related causes. The living conditions in the parental home, i.e. the manual class and one-parent family, had an effect on the transitions a person experienced in youth, and thus contributed to the effect youth paths exerted on adult social class differences in mortality from various causes of death. Youth paths had a substantial effect (about 60-90%) over and above the preceding effect of living conditions in the parental home on mortality. The higher mortality in the lower social classes was mainly attributable to disadvantageous educational path. Moreover, both family formation, particularly early marriage in women and staying single in men, and experience of unemployment in youth, had independent effects on class differences in mortality. These results strongly suggest that youth is a ‘sensitive period’ affecting social class differences in mortality in middle adulthood.
  • Aaltonen, Jaakko (Helsingin yliopisto, 2007)
    Solid materials can exist in different physical structures without a change in chemical composition. This phenomenon, known as polymorphism, has several implications on pharmaceutical development and manufacturing. Various solid forms of a drug can possess different physical and chemical properties, which may affect processing characteristics and stability, as well as the performance of a drug in the human body. Therefore, knowledge and control of the solid forms is fundamental to maintain safety and high quality of pharmaceuticals. During manufacture, harsh conditions can give rise to unexpected solid phase transformations and therefore change the behavior of the drug. Traditionally, pharmaceutical production has relied on time-consuming off-line analysis of production batches and finished products. This has led to poor understanding of processes and drug products. Therefore, new powerful methods that enable real time monitoring of pharmaceuticals during manufacturing processes are greatly needed. The aim of this thesis was to apply spectroscopic techniques to solid phase analysis within different stages of drug development and manufacturing, and thus, provide a molecular level insight into the behavior of active pharmaceutical ingredients (APIs) during processing. Applications to polymorph screening and different unit operations were developed and studied. A new approach to dissolution testing, which involves simultaneous measurement of drug concentration in the dissolution medium and in-situ solid phase analysis of the dissolving sample, was introduced and studied. Solid phase analysis was successfully performed during different stages, enabling a molecular level insight into the occurring phenomena. Near-infrared (NIR) spectroscopy was utilized in screening of polymorphs and processing-induced transformations (PITs). Polymorph screening was also studied with NIR and Raman spectroscopy in tandem. Quantitative solid phase analysis during fluidized bed drying was performed with in-line NIR and Raman spectroscopy and partial least squares (PLS) regression, and different dehydration mechanisms were studied using in-situ spectroscopy and partial least squares discriminant analysis (PLS-DA). In-situ solid phase analysis with Raman spectroscopy during dissolution testing enabled analysis of dissolution as a whole, and provided a scientific explanation for changes in the dissolution rate. It was concluded that the methods applied and studied provide better process understanding and knowledge of the drug products, and therefore, a way to achieve better quality.
  • Lonka, Eila (Helsingin yliopisto, 2014)
    ABSTRACT Individuals with profound deafness have damages in the inner and outer hair cells in the cochlea. For this reason they make only little use of frequency information and thus have minimal capacities to perceive speech sound cues. Accordingly, speech perception without augmentative means is impossible for them. Profoundly deaf children have been deprived of sound from very early stages of their lives, which inevitably has an effect on linguistic development. Cochlear implants (CIs) have proved their advantage in compensating auditory deficiency both in adults and children with profound hearing loss. In Helsinki University Hospital cochlear implantations started in the early 1980s for 10 Finnish adults with profound deafness. Since that time, due to the fast development of speech processing strategies introduced to CIs, high frequencies and temporal features important to the discrimination of consonantal cues and understanding continuous speech are now often available. The up-to-date worldwide estimation of adults using CIs is 200 000, and the respective number of children is 80 000. In Finland the estimated number of children with CIs is approximately 300, and 500 adults, respectively. In Studies I and II we followed the development of MMN responses to vowel and frequency stimuli in postlingually deafened adults. Plasticity of auditory pitch discrimination driven by cochlear implant (CI) use during a 2.5-year follow-up was indicated both by an enhancement of the amplitude of mismatch negativity (MMN) event-related brain potential (ERP) to vowel contrasts as well as to pure tone frequency changes. The MMN was observed in all patients after 2.5 years of CI use. It was first seen for the larger vowel difference /e/-/o/ and later for the smaller one /e/-/ø/. A significant enhancement was observed for the MMN elicited by 3200 Hz deviant tones among 4000 Hz standards. Instead, no observable mean amplitude MMNs were seen in duration stimuli. The MMN results were compared to audiometric speech recognition scores (SRSs) which improved over time. Participants with the highest SRSs had the highest MMN amplitudes. Studies III (n = 92) and IV (n = 164) report auditory and spoken language development as well as educational settings for Finnish children with cochlear implants. The results of the 92 children show that after approximately three years of hearing experience (hearing age = HA) at the mean chronological age of seven years, children are achieving developed forms of spoken language. The favourable age of two to three for early cochlear implantation in respect to good spoken language skills development was observed in 55 children. For Study IV, two questionnaires were employed; the first, concerning day care and educational placement, was filled in by professionals for rehabilitation guidance, and the second, evaluating language development (categories of auditory performance, spoken language skills, and main modes of communication), by speech and language therapists in audiology departments. Categories of auditory performance and spoken language levels were observed to grow in relation to age at cochlear implantation (p less than 0.001) as well as in relation to proportional hearing age (p less than 0.001). The composite scores for language development moved to more diversified ones in relation to increasing age at cochlear implantation and proportional hearing age (p less than 0.001). Furthermore, the results also indicated that nearly half of the children were enrolled in normal kindergartens and 43% of school-aged children in mainstream schools. Children without additional disorders outperformed those with additional disorders. The results of Study IV indicate that the most favourable age for cochlear implantation could be about the age of two. Compared to other children, spoken language evaluation scores of those with additional disabilities were significantly lower; however, these children showed gradual improvements in their auditory perception and language scores. Taken together, the positive effects of cochlear implantation were observed in MMN responses in adults and in behavioral results for children with CIs.
  • savolainen, tarja (2002)
    The subject of the study was Finnish women as film directors before 1962. Women's relation to film-making was approached as a negotiation between the director and film production. The analysis focused on questions involving the general events in society and especially in film production, as well as how women got their chances to direct films and what kind of meanings did women give to these opportunities. The study also explored how their personal resources, i.e. economic, cultural and social capitals, influenced their possibilities for attaining their positions in film production. The research shows that women were already interested and involved in film in many ways during the era of silent film. However, women did not direct before the 1930s and only three women directed a full length feature film. Ten film-makers of short films were found, but only three of them made several short films shown in the theatres. Seven women made 16 millimetre films and only a few 8 millimetre films. The chance for all three feature film directors to direct came suddenly, during a film production boom, when there was a lack of film directors. Regardless of how they became directors, they used their opportunities actively for different purposes. Eva-Lisa Viljanen and Brita Wrede represented film-makers of short films in the study. Viljanen negotiated her position by making travel films and depicting business life as a part of the construction project of the Finnish nation. Wrede negotiated her position as a film-maker of refugee films in Sweden and Finland during the Second World War and soon after that. The personal resources of short film-makers, especially economic capitals, influenced their possibilities for begining film-making. However, the directors of feature films could not attain their positions by means of personal capitals.
  • Eigensperger, Nina Katarina (2001)
    The research object is Swiss public opinion on European integration, which is weighty in Switzerland due to one of the centrepieces of its political system: direct democracy. If the Swiss Federal Government’s wants to adhere to collective security organisations or supranational communities, a mandatory referendum has to be held. The acceptance of such international treaties requires a double majority: a majority of the citizens and of the cantons. Until the 1990s Switzerland’s foreign policy used to be characterised by encapsulation and conscious political abstinence. Therefore the number of foreign policy related plebiscites was nearly non-existent. Yet, since the Swiss Federal Government’s strategic objective regarding its European integration policy became joining the European Union as a full member, public opinion is probably more important than ever before. The main objective of this research is to identify – within the given theoretical framework – the core factors that determine Swiss public opinion on Switzerland’s potential membership in the European Union. The results of previous research have been rather controversial as to the kind of factors that are decisive: certain researchers assert that it is the anticipated economic impact of the market liberalisation on the voters’ personal welfare that account for their voting behaviour, whereas others claim that sociocultural factors (such as identity) determine Swiss citizens’ voting decision. This study is a combination of descriptive and explanatory research. The principal research method is regression analysis as to account for the main objective of identifying the core factors. Cross tabulations were used for descriptive purposes. The results obtained from the empirical data – Swiss Eurobarometer 1999 – indicated that all three hypotheses proved to be robust when tested individually. Yet when all potentially decisive factors were examined simultaneously in one model, only three factors were clearly more important than the rest: federalism as a part of Swiss national identity and party identification with two of the four governmental parties (Social Democratic Party or Swiss People’s Party). Hence, within the given framework, sociocultural factors are considered to be more decisive than economic factors in determining Swiss citizens’ support for membership in the European Union.
  • Eigensperger, Nina Katarina (2001)
    Tämän pro gradu -tutkielman tutkimuskohteena on sveitsiläinen kansalaismielipide Euroopan yhdentymisen suhteen, mikä on hyvin merkityksellinen Sveitsissä johtuen sen poliittisen järjestelmän yhdestä keskeisestä instituutiosta: suorasta demokratiasta. Mikäli Sveitsin liittohallitus haluaa liittyä kollektiivisen turvallisuuden organisaatioon tai ylikansalliseen yhteisöön, kansanäänestys jäseneksi liittymisestä on pakko pitää. Tälläisten kansainvälisten sopimusten hyväksyntä edellyttää kaksinkertaista enemmistöä: sekä kansalaisten että kanttoonien. Ennen 1990-lukua Sveitsin ulkopolitiikkaa luonnehtivat tietoinen poliittinen pidättäväisyys ja itseensä käpertyminen. Näin ollen ulkopolitiikkaan liittyvät kansanäänestykset olivat lähes olemattomia. Siitä lähtien kun Sveitsin liittohallituksen strategiseksi päämääräksi tuli liittyminen täysjäsenenä Euroopan unioniin, niin Euroopan yhdentymiseen kohdistuvasta kansalaismielipiteestä tuli tärkeämpi kuin koskaan ennen. Tutkimuksen päätavoitteena on löytää tämän työn viitekehyksen puitteissa ne päätekijät, jotka määräävät Sveitsin kansalaisten mielipidettä maansa potentiaalisen EU-jäsenyyden suhteen. Aikaisemman tutkimuksen tulokset ovat olleet jokseenkin ristiriitaisia: tiettyjen tutkijoiden mukaan markkinoiden vapautumisen vaikutukset kansalaisten henkilökohtaiseen taloudelliseen hyvinvointiin määräävät äänestäjien äänestyskäyttäytymisen, kun taas toiset tutkijat väittävät sosiokulttuuristen tekijöiden (kuten identiteetin) olevan hallitsevia Sveitsin kansalaisten äänestyspäätöksessä. Tämä tutkimus on yhdistelmä kuvailevaa ja selittävää tutkimusta. Päämenetelmänä on käytetty regressioanalyysiä, jonka avulla on ratkaistu tutkimuksen päätavoite eli löydetty kansalaismielipiteeseen vaikuttavat päätekijät. Ristiintaulukointia on käytetty kuvaileviin tarkoituksiin. Empiirisen aineiston avulla – Sveitsin Eurobarometri 1999 – saavutetut tulokset puoltavat jokaista kolmea hypoteesiä silloin kun niitä testattiin erikseen. Kun kaikkia potentiaalisesti määrääviä tekijöitä tutkittiin samanaikaisesti yhdessä ainoassa mallissa, vain kolme tekijää osoittautui enää selvästi muita tärkeämmäksi: federalismi osana Sveitsin kansallista identiteettiä ja samastuminen kahteen neljästä hallituspuolueesta (Sosiaalidemokraattinen puolue ja Sveitsin kansanpuolue). Näin ollen tämän viitekehyksen puitteissa sosiokulttuuriset tekijät osoittautuivat hallitsevimmiksi kuin taloudelliset tekijät Sveitsin kansalaisten EU-jäsenyyden kannatuksessa.
  • Holopainen, Pirkko (1999)
    The research material was collected earlier in connection with personality tests. In this research the personality items are used as independent variables. The aim of the research was to examine personal and social elements and their relations and changes during a period of 1.5 years. Further aims was to examine the life and development of adolescents at the age of 13.5-15. The emphasis was especially on gender differences, family environment and peer issues. The study was based on the data of risk behavior of adolescents collected by questionnaires in 1985-88. The sample consisted of students from 5th to 9th grades in three schools. The questionnaire consisted of items about success of the students at school, their personality (Eysenck Junior-EPI), self-esteem (Coopersmith), locus of control (Nowicki - Strickland), psychosomatic symptoms and risk behavior. The study was quantitative. The correlative analyses supported the researcher's idea to divide variables into personal and social elements. Factor analysis was used to reveal relevant social and personal dimensions. Using three separate factor analysis, the following factor pairs and one single factor were named: family support and positive self-concept, peer activity and psychological balance, outward-oriented adolescent and popularity among peer. Psychosomatic behavior was examined separately. The reliability (Tarkkonen 1987) was between 0.901 and 0.711. Second order factor analysis was used to examine variables based on factors, their relations to each other and their changes during the 1.5 years. After the second order factor analysis two new factors were named: the personality- and family factor and the social factor. Cross-tabulated data based on personality- and family factor and social factor as axis revealed the structure of personal and social welfare of adolescent, reflecting also self-concepts. Especially social (peer issues) but also personal component of the structure changed during 1.5 years. The family support were salient to girls at the age of 13.5 and to boys at the age of 15. Peer issues were important for both genders. Popularity with peer and risk behavior (smoking and alcohol abuse) were more salient to girls than boys. Positive self-concept of girls was connected to the peer issues and that of boys to the family support. The maturing process takes different paths in timing and in the contents of different development areas. Coopersmith (1967), Eysenck (1967, 1981), Nowicki - Strickland (1972, 1973), Emmerich ym. (1971).
  • Jutila, Eero (Helsingin yliopisto, 2008)
    Long-term monitoring data collected from wild smolts of Atlantic salmon (Salmo salar) in the Simojoki river, northern Finland, were used in studying the relationships between the smolt size and age, smolt and postsmolt migration, environmental conditions and postsmolt survival. The onset of the smolt run was significantly dependent on the rising water temperature and decreasing discharge of the river in the spring. The mean length of smolts migrating early in the season was commonly higher and the mean age always older than among smolts migrating later. Many of the smolts migrating early in the season and almost all smolts migrating later had started their new growth in spring in the river before their sea entry. Among postsmolts, the time required for emigration from the estuary was dependent on the sea surface temperature (SST) off the river, being significantly shorter in years with warm than cold sea temperatures. After leaving the estuary, the postsmolts migrated southwards along the eastern coast of the northern Gulf of Bothnia, the geographical distribution of the tag recoveries coinciding with the warm thermal zone in spring in the coastal area. After arriving in the southern Gulf of Bothnia in late summer the postsmolts mostly migrated near the western coast, reaching the Baltic Main Basin in late autumn. Until the early 1990s there was only a weak positive association between smolt length and postsmolt survival. However, following a subsequent decrease in the mean smolt size, a significant positive dependence was observed between smolt size and the reported recapture rate of tagged salmon. The differences in recapture rates between smolts tagged during the first and second half of the annual migration season were insignificant, indicating that the seasonal variation in smolt size and age seem to be too small to affect survival. Among the climatic factors examined, the summer SST in the Gulf of Bothnia was most clearly related to the survival of the wild postsmolts. Postsmolt survival appeared to be highest in years when the SST in June in the Bothnian Bay varied between 9 and 12 ºC. In addition, the survival of wild postsmolts showed a significant positive dependence on the SST in July in the Bothnian Sea, but not on the abundance of the prey fish (0+ herring, Clupea harengus and sprat, Sprattus sprattus) in the Bothnian Sea and in the Baltic Main Basin. The results suggest, that if the incidence of extreme weather conditions were to increase due to climatic changes, it would probably reduce the postsmolt survival of wild salmon populations. For improving the performance of hatchery-reared smolts, it could be useful to examine opportunities to produce smolts that are in their smolt traits and abilities more similar to the wild smolts described in this thesis.
  • Tonttila, Juha (Helsingin yliopisto, 2015)
    Clouds, aerosols and the interactions between them are some of the most important uncertainties in climate modelling. The scales of spatial variability related to clouds are generally too small to be resolved using a typical climate model grid resolution. This work comprises studies about the small-scale variability of the vertical wind component, which significantly contributes to the process of cloud droplet formation. In addition, more elaborate methods for describing the small-scale variability of cloud properties in climate models are developed. The key questions that are investigated include: 1) What are the statistical properties of the turbulent vertical wind variability in the boundary layer and can they be represented accurately by atmospheric models? 2) How does parameterizing the small-scale variability in cloud microphysical processes affect the simulated cloud properties in climate models? 3) How does accounting for the small-scale variability in cloud properties affect the model-based estimates of the aerosol indirect radiative effects? The most important tool used in this work was the ECHAM5-HAM2 aerosol-climate model. The model simulates not only the atmospheric circulation and thermodynamics, but also the global distribution of aerosols and the physical processes between particles that affect the aerosol particle population. This allows the model to represent the interactions between clouds and aerosols. In addition, parts of this work also make use of measurement data based on remote sensing methods as well as high-resolution output from a numerical weather prediction model. The results show that the small-scale variability of the vertical wind associated with cloud droplet formation must be parameterized even in models with relatively high grid resolution. This highlights especially the importance of such methods for lower-resolution climate models. The variability of vertical wind can be described using a probability density function (PDF), the shape of which may vary significantly depending on the atmospheric conditions. The intricacies of the PDF include many uncertainties which can only be reduced by more extensive observations. With a simplified representation of the vertical velocity PDF, a new version of the climate model is constructed in this work, which can be used to study the climate effects due to the small-scale variability in vertical wind and clouds. It is noted that earlier methods that try to account for the variability in vertical velocity and cloud formation are somewhat insufficient. More attention should be paid on treating the small-scale variability self-consistently for entire chains of processes rather than separately for individual processes. This was accomplished in this work with the newly developed method, comprising the chain of processes from cloud formation to radiative transfer. The new method has a strong impact on the number of cloud droplets and drizzle formation as compared to the default model version, where the small-scale variaiblity of clouds is not as accurately accounted for. Moreover, the response of the model-simulated cloud properties to anthropogenic changes in aerosol emissions is found to be considerably weaker in the new model version than in the default model version. In effect, when compared with the default model version, the aerosol indirect radiative effect estimated with the new model version is closer to the best observation-based estimate. The results of this work contribute to improving our understanding of the aerosol-cloud interactions and to guide the work towards further reducing the uncertainties related to modelling clouds and climate.
  • Viinamäki, Miia (Helsingin yliopisto, 2015)
    Ruisleipä on keskeinen elintarvike suomalaisten ravitsemuksessa. Sen valmistuksessa käytetään yhä perinteistä juuritaikinaa eli raskia, joka sisältää maitohappobakteereja ja mahdollisesti hiivoja. Ruis sisältää runsaasti fruktaaneja ja lisäksi raskin fermentoinnin aikana muodostuu mannitolia. Fruktaani ja mannitoli imeytyvät huonosti ohutsuolesta, mutta suoliston bakteerit fermentoivat ne nopeasti. Nopeasti fermentoituvat substraatit saattavat aiheuttaa vatsaoireita jopa yli 10 % väestöstä. Opinnäytetyössä tutkittiin erään teollisen raskin fruktaani- ja mannitolimetaboliaa, raskimikrobistoa sekä raskimikrobiston fruktaaninhajottamiskykyä. Tutkimuskohteeksi valittiin BF-raski. BF-raskin fruktaanin, mannitolin ja pelkistettyjen sokerien pitoisuutta mitattiin raskituksen edetessä. Mittausten jälkeen käyttövalmiista BF-raskista eristettiin maitohappobakteerit ja niiden fruktaanin hajottamiskykyä testattiin kromogeenisillä maljoilla ja puhdasviljelmistä tehdyillä fermentaatioilla. Lisäksi valmistettiin BF-raskin kaltainen spontaani raski pienessä mittakaavassa ja mitattiin sen fruktaanipitoisuutta. Tutkimuksessa havaittiin, että BF-raskin raskitusprosessin aikana fruktaani ja prosessissa syntynyt mannitoli hävisivät. Yhdellä raskin maitohappobakteereista havaittiin olevan kyky kuluttaa tehokkaasti fruktaania ja geenit, jotka koodaavat solunulkoista fruktaanihydrolaasi-entsyymiä sekä FOS/fruktoosi-kuljetussysteemiä. Lisäksi siltä löytyivät mannitolin käyttöön tarvittavat geenit. BF-raskin kaltainen fruktaania kuluttava raskisysteemi saatiin aikaan myös spontaanisti pienemmässä mittakaavassa. Fruktaanivapaan ruisraskin avulla voidaan valmistaa niukasti fruktaania ja mannitolia sisältävää ruisleipää. Tällainen ’vatsaystävällinen’ ruisleipä voisi sopia perinteisestä ruisleivästä vatsaoireita saaville kuluttajille.
  • Hästö, Mikael (2014)
    Temat i studien är eftervård för klienter som genomgått rehabiliteringsvård för missbrukare i Helsingfors. De centrala forskningsfrågorna är ”hur upprätthålls kontakterna till eftervården under rehabiliteringsperioden?” och ”hurdant stöd erbjuds brukarna efter vårdperioden?”. Genom temaintervjuer med åtta 33-63 år gamla rehabiliteringsklienter som alla genomgått vårdperiod på Helsingfors stads rehabiliteringscenter Tervalampi gård, samt deltagande observation och dokument över från Tervalampi besökta eftervårdsinstanser och fyra slutbedömningar från rehabiliteringsperioden har jag genom innehållsanalys som huvudsaklig analysmetod kommit fram till resultaten i studien. Motivation, ensamhet, sociala nätverk och eftervård är centrala teman som diskuteras i studien. Studien avser måla upp en bild över olika möjliga aktörer hos till vardagen återkomna rehabiliteringsklienter samt ge en inblick i personernas sociala nätverk och vardag. Jag har vid analys av intervjuerna utgått ifrån Thomas J. Scheffs och Howard S. Beckers stämplingsteorier och Ulla-Carin Hedins teori kring uppbrottsprocessen. Dessa har fördjupat förståelsen av materialet i studien. Motivation har en ytterst central roll i studien, eftersom eftervården visar sig hänga på klienternas egen motivation och engagemang. Motivationen styr eftervårdsbanan och därigenom rusmedelsbruket till viss del. Även ett stödjande socialt nätverk visar sig vara av yttersta vikt för att motarbeta ensamheten som framkommit i flera intervjuer. Tervalampi gård visar sig ha en ytterst viktig roll i att tillsammans med klienterna skapa eftervårdsnätverk att stöda klienternas mål att uppnå långvarig nykterhet. Eftervårdsnätverket börjar skapas redan under rehabiliteringsperioden och alla respondenter i studien håller med om att eftervård är en förutsättning för att stöda den egna nykterheten.
  • Beurling, Juha Tuomas (2005)
    Syftet med undersökningen är att undersöka hurdana viktiga och betydande integrationsåtgärder Helsingfors stad har implementerat för invandrare under tidsperioden 1997-2004. Jag undersöker också inverkan av dessa integrationsåtgärder på utvecklingen av arbetslösheten bland invandrare i Helsingfors. Invandrarpolitiken i Helsingfors behandlar jag också i korthet samt olika hinder som invandrare möter på sin väg till integration. Som mått för att mäta utvecklingen av invandrares integration använder jag utvecklingen av arbetslösheten bland invandrare. Som teori använder jag implementeringsteori och jag koncentrerar mig på nätverksimplementeringen. Som ett viktigt antagande har jag att utfallen av olika integrationsåtgärder bevisar om informella nätverken bland invandrare och myndigheter fungerar. Som källor använder jag flera olika forskningar om mätning av integration. Lennart Lundqvists bok Implementation Steering samt Bo Rothsteins bok Politik som organisation är viktiga verk för att bygga den teoretiska referensramen i undersökningen. Helsingfors utlänningspolitik från år 1995 och Helsingfors stads integrationsprogram är också centrala källor i denna undersökning. Arbetslösheten bland invandrare har avsevärt minskat och skillnaden mellan arbetslöshetsprocenten bland invandrare och bland så kallade stamfolket är bara några procent. Detta betyder i alla fall inte att integrationen bland alla nationaliteter skulle ha skett med samma takt eller lika bra. I alla fall på grund av detta faktum drar jag slutsatsen att invandrare har integrerar sig bättre i slutet av forskningsperioden än i början av perioden I Nils Herttings normativa tes om nätverksstyrning ses lokala samverkansnätverk kring avgränsande samhällsproblem som nödvändiga instrument för att säkerställa legitim och effektiv offentlig politik. Alla de nya samarbetsformerna i invandrarärenden i Helsingfors som har kommit fram i denna undersökning hänvisar till att nätverksstyrningens normativa idé gäller i Helsingfors invandrarpolitik. Enligt implementeringsteori som förutsätter att tillämparen skall kunna och vilja implementera beslutet samt förstå beslutet kan man säga att de tillämpande myndigheterna i Helsingfors har uppfyllt dessa kriterier åtminstone delvis. Detta bevisar utfallen av de betydande integrationsåtgärder som jag presenterat i min undersökning.
  • Blomqvist, Johanna (2004)
    I uppsatsen undersöker jag med både kvantitativa och kvalitativa metoder hur användningen av berättartekniker i tre dagstidningars reportagetexter har förändrats under de tre senaste decennierna. Syftet var att ta reda på om det stämmer att reportagen har blivit "tråkigare" och mindre personliga, vilket tycks vara en allmän uppfattning. De undersökta tidningarna är Dagens Nyheter, Hufvudstadsbladet och Västra Nyland, och som material använder jag texter från år 2002, 1987 och 1972. De fyra berättarteknikerna jag undersöker är förekomsten av berättelsestruktur, reporterns egen röst i texten samt miljö- och personbeskrivningar. Min kvantitativa mätning visar att det inte finns någon gemensam trend som gäller alla tidningarna. I DN syns en negativ trend mellan 1972 och 1987, med färre berättelser och mindre personliga texter, men den har svängt i och med de nya specialbilagorna som ofta satsar stort på reportage. Både Hbl och VN har genomgått en positiv förändring under den första 15-årsperioden, då texterna har blivit klart mer varierade och mindre stela. Indelningen i reportage och nyheter är dock klarare i DN än i Hbl och VN, vilket har lett till att reportagen i Hbl och VN under den andra 15-årsperioden också har påverkats mer av nyhetsformatet. Den andra delen av min undersökning är en textanalys av 17 utvalda reportagetexter, där jag mera på djupet diskuterar texternas egenskaper. Resultaten stöder de jag fick i den kvantitativa undersökningen: Referat och framför allt citat utgör den största delen av texten, medan reporterns egen röst hörs mera sällan. Reporterns röst har dessutom ändrat karaktär - han nöjer sig numera med att beskriva, i stället för att tycka och tolka som förr. Min slutsats är att tidningarnas specialbilagor har varit ett lyckat koncept då det gällt att stärka reportagets ställning. Detta syns speciellt i DN men också i Hbl. Därmed ser också dagstidningsreportagets framtid trots allt ganska ljus ut idag.
  • Koivunen, Jenna (2014)
    I denna pro gradu avhandling behandlas socialarbetares samt socialhandledares uppfattningar om hembesök som praktik. De centrala forskningsfrågorna för pro gradu avhandlingen är: 1) Hur beskriver socialarbetare och socialhandledare dessa hembesök inom vuxensocialarbete? 2)Hur förhåller sig socialarbetare och socialhandledare till hemmet som arena för professionellt arbete inom vuxensocialarbete? samt 3) Vilka betydelser läggs i arbetet och hur ser socialarbetare och socialhandledare på sin roll och de utmaningar de idag möter? Syftet med studien är att bidra till en större förståelse för hembesökens betydelse i vuxensocialarbete under ekonomiskt pressade tider då kraven på effektivitet ökar. Avhandlingen är en kvalitativ studie. Fyra socialarbetare samt fyra socialhandledare inom vuxensocialarbete intervjuades om deras uppfattningar av hembesök som praktik. Intervjuerna har analyserats med hjälp av innehållsanalys. Som teoretisk referensram har jag använt mig av Lipskys teori om gräsrotsbyråkrater samt Högströms teori om rum och diskurs. Lipskys (1980) teori om gräsrotsbyråkrater har främst legat till grund för att få en mera övergripande förståelse för hur vuxensocialarbetet organiseras samt hur olika faktorer som exempelvis ekonomiska aspekter, direktiv samt antal klienter påverkar hur socialarbetare diskuterar om sitt handlingsutrymme samt om hembesök som praktik. Med hjälp av Högströms (2012) teori om rumstriangeln visar jag hurudan betydelse hemmet och dess materiella rumsliga aspekter har för hur socialarbetare uppfattar hembesök som praktik samt som professionell arena. Analysen har kodats i tre olika huvudkategorier med vilka jag besvarar mina centrala forskningsfrågor: 1) hembesök som praktik 2) beskrivningar av hemmet, och 3) Spända relationer – intrång i hemmet. Varje huvudkategori är indelad i underteman. Dessa tre kategorier besvarar mina centrala forskningsfrågor. I resultaten framkommer det att hembesökens värde ligger i att de ger en realistisk och omfattande bild av klientens livssituation, som fördjupar kunskapen och bedömningen av klientens situation och kan därmed öka effektiviteten och kvaliteten på vuxensocialarbete. Hembesöken skapar betydelsefulla insikter i klientens vardag. Ett annat centralt resultat i studien är att hembesök betraktas som en intervention i de fall där klienten har mångfacetterade problem som exempelvis fysiska eller psykiska hinder, hyresskulder, vräkning, missbruksproblem, samlarmani och utkomststödsrelaterade frågor. Ett central resultat i studier är att hembesök inverkar positivt och gynnsamt på klientrelationen. Klienterna känner sig mer avslappnad i det egna hemmet och det har en positiv inverkan på mötet, i motsats till om klienten och socialarbetaren träffas på byrån. Studien visar att hemmiljön är ett tryggt ställe för klienten. Hemmet kan ändå upplevas som en begränsande arena för att utöva det professionella arbetet eftersom hembesök kan innebära intrång i klienternas vardagsliv och dess rutiner. Socialarbetarnas arbete styrs av direktiv, som inverkar konfliktfyllt på möjligheterna att göra hembesök. Stränga direktiv och krav på effektivitet leder till att man prioriterar att göra utkomststödsbeslut framför att göra ett hembesök. Studien visar dock att det finns vilja i framtiden att göra betydligt mera hembesök.
  • Söderlund, Ilkka J I (2016)
    I avhandlingen konstrueras de naturliga talen utgående från mängdlärans axiom. Från de naturliga talen och deras egenskaper som bevisas i arbetet fortskrider avhandlingen steg för steg till de hela talen, de rationella talen och de reella talen. Bland de första stegen visar vi att det existerar en induktiv mängd som satisfierar Peanos axiom. Sedan bevisas rekursionsteoremet som används för att bygga upp aritmetiken för de naturliga talen. Genom ekvivalensrelationen $\langle m,n \rangle \sim \langle p,q \rangle \Leftrightarrow m+q=p+n$ konstrueras de hela talen som ekvivalensklasserna $\Z = (\N \times \N)/\sim$. I arbetet bevisas grundläggande aritmetiska regler för de hela talen samt gällande ordningsrelationen. På ett liknande sätt konstrueras mängden av rationella tal från mängden av hela tal med hjälp av ekvivalensrelationen $\langle a,b\rangle \sim \langle c,d\rangle \Leftrightarrow ad=bc$ där $a,b,c,d \in \Z$. I arbetet bevisas att mängden av rationella tal bildar en kropp. Även talföljder och därmed även fundamentalföljder studeras som en förberedelse för konstruktionen av de reella talen. I det sista steget, där vi konstruerar de ekvivalensrelationer som bygger upp de reella talen, så används en annan metod till skillnad från de hittills algebraiska metoderna. Ekvivalensrelationen baserar sig på fundamentalföljder i mängden av rationella tal. Vi definierar en ekvivalensrelation $(x_n)\sim (y_n)$ i mängden av fundamentalföljder $F_\Q$ genom gränsvärdet $L(x_n-y_n)=0$. Förutom att egenskaper för räkneoperationerna och ordningsrelationen bevisas, så visas även att mängden av de reella talen är fullständig. Som avslutning till avhandlingen granskas isomorfier mellan de konstruerade mängderna och icke-numrerbarheten av mängden reella tal.