Väitöskirjat: Recent submissions

Now showing items 1-20 of 7857
  • Lahtinen, Joonas (Helsingin yliopisto, 2020)
    This study discusses the transformative potential of contemporary participatory performance practice and the possibilities for locating and interrogating it through performance analysis that pays special attention to the dynamic of human perception. The writer suggests that the crucial ideological assumptions, power relations, as well as the processes of exclusion and inclusion of participatory projects, are not to be seen solely in their “goals” or “themes”, but, even more distinctly, in the modes of bodily participation that they employ. The study consists of a theoretical part and three case study analyses. In the theoretical part, the writer presents a novel analytical framework for addressing the ways in which artistic performances engage and affect their participants, and for understanding the culture-bound dynamic of perception, power, knowledge and the body both in participatory performance situations and in our everyday lives. Drawing especially on the views of human perception, power, and experience of Jacques Rancière, Marcel Mauss, and Michel Foucault, the main concepts of this framework are “sensory fields”, “experience fields” and “body techniques”. As for the verbalization of experiences through performance analysis, the framework draws on Joe Kelleher’s and Alan Read’s notions of “theatre images”. Based on the analytical framework, the writer locates and interrogates “politics of the sensible” i.e. modes of participation; underlying assumptions regarding the participants and the efficacy of the chosen participatory strategy; potential inclusions and exclusions; and horizons of change in Lois Weaver’s "What Tammy Needs to Know" (2006) and "What Tammy Needs to Know about Getting Old and Having Sex" (2008), the Complaints Choirs of Helsinki (2006), Singapore (2008) and Vienna (2010 –) based on the "Complaints Choir" project concept by Tellervo Kalleinen and Oliver Kochta-Kalleinen, and "dominant powers. was also tun?" (2011) by Claudia Bosse and her group, theatercombinat. This study also shows how all of these projects embody features of post-Fordist work and how they relate to the ethos of de-alienation in participatory art practice. Besides locating productive transformatory potential and tendencies in all of these performances, this study brings about critical perspectives and notions that have not been addressed in previous research on Weaver’s, Kalleinens’ and Bosse’s projects. The writer suggests that the analytical framework presented in this study provides new insights into perception, power and the body in performance theory and analysis, and may also offer productive inputs for artist-researchers, curators and art educators in planning and reflecting on their projects, and for scholars in areas such as epistemology, semiotics, and political science.
  • Rankinen, Juho (Helsingin yliopisto, 2020)
    The study concentrates on negligence as a positive fault requirement in the Finnish criminal law. The hermeneutical aspiration of the study is to understand this concept and a form of legally relevant fault – i.e., to understand what is criminal negligence. This requires some kind of understanding what is criminal law, and law in general. Merely the aim to understand the law leads this study into enormous philosophical problems. According to this study, law is something far too complex, ambiguous and even mysterious to be grasped by this study, or the undersigned researcher. And so is also the Finnish criminal law, and eventually negligence. Consequently, the study is plunged into a pluralistic, eclectic and in many ways paradoxical cavalcade of perspectives and points of view. It cannot claim to possess some kind of absolute truth, neither concerning law, nor criminal law, nor negligence. Still, it hopes to advance our understanding concerning these issues. It has to resign itself to better understand negligence. The study is composed of five main sections. The first one frames the methodological and ethical theses for the research. The second one (PART I) examines the tradition of finnish criminal law and different kinds of manners in which criminal negligence has already been researched. The third one (PART II) sketches a basic model in which more specific criminal law doctrines concerning fault and responsibility may be placed, and how criminal negligence may be thought as a coherent whole. The fourth one (PART III) draws conclusions from the basis of this model, trying both to apply it to questions of negligence in practical legal reasoning, and also to justify this model. The final section turns (back) to the eternal questions about legal knowledge, interpretation and belief. This study both assumes and also tries to show and even demonstrate the aporetic nature of law and it’s openness to interpretations. It aims to do this tangibly, rambling around in the mass of various researches, interpretations and perspectives concerning criminal negligence. A couple of pages abstract is probably one of the best ways to misunderstand this kind of enterprise. So, one page as an abstract will do.
  • Pokharel, Kisun (Helsingin yliopisto, 2020)
    The conservation, characterization, and sustainable utilization of farm animal genetic resources have far-reaching socioeconomic effects. Finnsheep, which is native to Finland, is globally known for its exceptional prolificacy and has been exported to several countries to improve the productivity of local breeds. Prolificacy, mainly determined by the ovulation rate and litter size phenotypes, has high economic importance in sheep farming systems. The ovulation rate is associated with the number of ovulatory follicles produced during the follicular growth phase of the estrous cycle, and successful implantation of the conceptus ensures maximum litters. The primary aim of this study was to evaluate the exceptional prolificacy of Finnsheep. Another important and overarching aim was to explore the genetic aspects of two important reproductive events leading to ovulation and successful pregnancy in sheep. To gain an insight into how these two processes are regulated genetically and non-genetically, the whole transcriptomes of selected reproductive tissues relevant to folliculogenesis (first phase, ovary) and early pregnancy prior to implantation (second phase, corpus luteum (CL) and endometrium) were analyzed. In the main experiment, the ovaries of 31 Finnsheep (n = 11) and Texel (n = 11) ewes as well as their F1 crosses (n = 9) collected during surgery were biopsied; other tissues, including the CL and endometrium, were collected at the slaughterhouse. Half of the animals were maintained on a flushing diet during the entire experiment to study the influence of nutrition during early pregnancy. In addition, the transcriptomes of the ovarian and endometrial tissues of Finnsheep ewes were compared to those of European feral mouflons. For transcriptomic analysis, cDNA libraries targeting mRNAs and microRNAs were sequenced using the Illumina HiSeq 2000 system with 100-base pair (bp) paired-end and 50-bp single-end techniques, respectively. Gene expression results from the first phase of the experiment revealed that the flushing diet strongly affected the Texel and, to some extent, the F1-crosses of sheep; however, Finnsheep were not affected by the diet. Likewise, the gene expression profiles of the F1 crosses were more similar to those of Finnsheep than of Texel, possibly because of the parent-of-origin effects, such as genomic imprinting. While no major candidate genes reportedly associated with prolificacy were differentially or highly expressed, FecGF polymorphism (V371M) in GDF9 was present in half of the experimental Finnsheep and F1 crosses but completely absent in the Texel sheep. The second phase of the experiment provided an insight on the cross-talk between the CL and endometrium, as revealed by both the shared and tissue-specific genes. Finnsheep had a higher embryo mortality rate than Texel. The top expressed genes were associated with progesterone formation and events (elongation and attachment), leading to blastocyst implantation. Several endogenous retroviruses (ERVs) were expressed in the endometrium samples. Immune-related genes and pathways appeared to be differentially expressed and/or regulated in the CL of pure-breds. During the preimplantation stage, the immune system of the Finnsheep ewes appeared superior to that of the Texel ewes. Owing to the influence of interferon tau in massive gene expression changes starting around day 13, the gene expression profiles of the endometrium samples in response to elongated embryos were remarkably different from those in response to spherical embryos. Moreover, several interferon-stimulated genes were upregulated in the endometrium samples having elongated embryos. In addition to differentially expressed genes between the reproductive tissues of domestic (Finnsheep) and feral (European mouflon) sheep, we identified novel genes and miRNAs and their regulatory mechanisms associated with reproductive traits. A few novel structural findings were obtained as part of this work. Maternally imprinted miRNA cluster on chromosome 18 (C18MC), which is conserved exclusively among placental mammals, was reported for the first time in sheep. With 46 expressed miRNAs, sheep C18MC may be the largest miRNA cluster among all mammalian species. The miRNAs (>500) quantified in this thesis are valuable, given that only 153 sheep miRNAs have been identified till date. A novel ERV transcript with high similarity to the genomic region within the FecL locus and known to affect prolificacy was identified, indicating that ERV plays an important role in reproduction and may even contribute to litter size differences. Overall, the work presented in this thesis explored two critically important aspects of reproduction, i.e., ovulation and preimplantation, in sheep using state-of-the-art genomics and bioinformatics tools. The resources and findings from this thesis are highly relevant to both breeders and researchers studying sheep. The comprehensive list of genes and miRNAs expressed in the three key reproductive tissues is a useful resource for understanding transcriptional patterns during the follicular growth phase and preimplantation stage leading to pregnancy in sheep. The diet- and F1 cross-related experimental results will be valuable for implementing sheep breeding strategies aimed at achieving an optimum reproductive capacity. Furthermore, these results will provide a foundation for future research, and the data may have additional applications following the advancement of analysis tools and technologies.
  • Abdurakhmanova, Shamsiiat (Helsingin yliopisto, 2020)
    The hypothalamus is one of the oldest brain structures and it is responsible for the regulation of vital homeostatic functions. A small population of the neurons containing neurotransmitters histamine and GABA, reside in the posterior hypothalamus. Activation of these histamine/GABA neurons promotes attentive wakefulness and vigilance state. In addition to its main role in supporting wake state, histamine released from histamine/GABA neurons is involved in controlling appetite, water intake and energy expenditure. Although the role of GABA released from the histamine/GABA neurons has been much less studied, it is suggested to provide tonic inhibition in the cortical and striatal regions. There are three major topics addressed in the current work. First, we aimed to further probe the hypothesis of the dual histamine/GABA neurotransmitter phenotype of the hypothalamic histaminergic neurons. We were especially interested in whether histamine/GABA neurons are able to release GABA into the synapse via the vesicular transport mechanism. Our second aim was to investigate the consequences of global histamine deficiency with a focus on the cortico-striatal system and brain dopamine-histamine interactions. Lastly, we studied the possible role of GABA released from histamine/GABA neurons in tonic extrasynaptic inhibition. It is well established that histaminergic neurons are also GABAergic, based on the presence of GABA producing enzyme - glutamic acid decarboxylase (GAD) and GABA itself in histaminergic neurons, as demonstrated by immunohistochemical methods. Contradictory findings have been reported on the presence of the vesicular GABA transporter (Vgat) in these neurons. We used double fluorescence in situ hybridization (dFISH) to simultaneously detect GABAergic markers (GAD67 or Vgat mRNA) with a marker for histaminergic neurons - histidine decarboxylase (Hdc) mRNA. We confirmed that histamine/GABA neurons express Vgat mRNA and are able to release GABA via a classical Vgat-dependent mechanism. Previous research has shown the interaction of histamine and dopamine systems at the level of the striatum and proposed involvement of these two systems in neuropsychiatric disorders such as Gilles de la Tourette syndrome. Using a mouse line lacking the histamine-synthesizing enzyme (Hdc KO mice), we investigated the role of histamine in the regulation of the striatal system and its interaction with dopamine at the striatal level. We measured striatal dopamine and its metabolites levels with high performance liquid chromatography (HPLC) at the baseline and after treatment with dopamine precursor l-3,4-dihydroxyphenylalanine (L-Dopa). By quantitative polymerase chain reaction (qPCR), we compared the levels of striatal prodynorphin and proenkephalin transcripts in Hdc WT and KO mice. The transcript level of prodynorphin and proenkephalin is tightly regulated by the activity of principal striatal neurons, medium spiny neurons (MSN) and various neurotransmitters such as dopamine and acetylcholine. Furthermore, we performed detailed analyses of exploratory open field behavior of Hdc KO mice and used a stereological approach to assess the morphology and cytoarchitecture of the corticostriatal system in these mice. We found that Hdc KO mice had increased dopamine turnover in the striatum and impaired expression of striatal prodynorphin and proenkephalin transcripts. We hypothesized that global deficiency of histamine leads to upregulation of the dopaminergic system in the striatum, which in turn leads to altered behavioral structure observed in the novel open field test. Impaired dynorphin/κ-opioid receptor inhibitory feedback on the dopaminergic terminals might be responsible for the increased striatal dopamine release. Finally, we provided new evidence suggesting that GABA released from the histamine/GABA neurons acts on the extrasynaptic δ subunit containing GABAA receptors and provides tonic inhibition. Pharmacological activation of the histamine/GABA neurons in the mice lacking GABAA δ subunit (Gabrd KO) led to a hypervigilant phenotype in these mice as was shown by EEG recordings. In conclusion, we showed that histamine together with dopamine regulates striatal circuits and that GABA released from the histamine/GABA neurons regulates brain arousal state at least partially through the extrasynaptic δ subunit containing GABAA receptors.
  • Mertanen, Katariina (Helsingin yliopisto, 2020)
    In this dissertation, I scrutinise how the ‘youth problem’—young people’s unemployment, social exclusion, and marginalisation—is governed in the European Union’s and Finland’s youth policies and youth policy implementation in Finland. The ‘youth problem’ as well as young people ‘at risk’ are constructed as a threat to the unity and prosperity of future life in the workforce and social cohesion. To tackle the ‘youth problem’, both the EU and Finland have launched multiple policy initiatives and implementations such as short-term projects to get young people ‘back’ into the workforce and undertake in education and training. These ranges of implementations include EU-wide policy measures, such as the Youth Guarantee and calls in Finland for centralised services for youth guidance and counselling. In my dissertation, I have analysed both national and EU policy documents along with interviews and observations produced with teachers, other employees, and young people in short-term education programmes in a closed prison, and in two One-stop Guidance Centres for young people. I ask how the ‘youth problem’ is governed in youth policies and their implementations, and what rationalities are involved in the governing of the ‘youth problem’. This dissertation includes three research articles and a summary report. As the methodology of this study I developed a discursive reading of policies and their implementations as problematisations. Reading discourses as problematisation draws inspiration from Carol Bacchi, that policies are simultaneous representations of desired futures from the policy maker’s point of view and representing a ‘problem’ that disrupts this desired future. By applying Michel Foucault’s theorisations about discourses, power, subjectification, and governing I have been able to study youth policies and their implementations as discursive practices. In youth policies, these discursive practices are legitimised in normative discourses based on political rationalities. Similarly, these discursive practices can be found in policy implementations by offering certain types of subjectivities for those young people they are targeting. Furthermore, these discursive practices in policies and their implementations produce several different ‘problems’ of young people that carry inherent assumptions about young people’s situations, properties, and abilities. In my results, I suggest that young people are produced as ‘at risk’ of social exclusion and marginalisation with discourses of employability, precariousness, and therapisation in youth policies and their implementations. The label ‘at risk’ produces a well-intentioned response, in which governing takes shape in skill-based behavioural training derived from employability and therapisation of youth formal and informal education. These skills include emotional and life-management skills. Discourses of employability, precariousness, and therapisation have a common premise: not being excluded or marginalised are synonymous with signs of visible and measurable activities, such as participating in education and training. Discourses in youth policies and their implementations both rely on and produce neoliberal political rationality along with paternalistic rationality, which promotes care and control of young people. Although seemingly contradictory, these rationalities work together in a plethora of ways. The arrangement and governing of youth policies and their implementations are constructed in a way in which vast networks of governmental, private and non-governmental organisations come together in short-term programmes and projects offered to young people, and in which young people are positioned as customers and expected to choose ‘right’ options for their situations. Yet, the ways in which young people are governed in these programmes rely on paternalistic rationality through which young people are seen not to be mature and insightful enough to know what is best for them and their future, and thus need strict discipline and guidance to move ‘forward’ in life. Finally, I conclude in this dissertation, that the whole notion of the ‘youth problem’ is based on the ideal of an economically productive citizen, who through a measurable input during their working life or from education provides continuity for the society as a whole. The notion of young people as a future is not only attached to the future hopes of young people themselves, but rather to the hopes and predictions of a range of governing bodies, such as the European Commission or the Finnish Government. In this way, multiple societal issues including poverty and unemployment are channelled to be young people’s ‘problems’, which can be solved by guiding those young people as individuals. In the governing of the ‘youth problem’ in youth policies and their implementations, young people have mainly instrumental value – their lives and futures are measured in relation to the narrow view of ‘good life’ as productive, obeying, and tax-paying future citizen. ________________________________________ Keywords: youth policy, governing, discourse, ‘youth problem’
  • Ikonen, Essi (Helsingin yliopisto, 2020)
    Authenticity is a pervasive ideal in western societies. Educators, among others, regard authenticity with increased enthusiasm. Authenticity is certainly appealing. Who would not want to be authentic rather than inauthentic? Who would not want to educate one’s children to become authentic? Yet, as attractive as it is, do we truly apprehend the nature of authenticity? How are we to detect an authentic person from an inauthentic one? Who is to decide which instances are authentic and which are not? The literature of authenticity offers us abundance of views and definitions, but no unanimous clarity. The challenges increase when trying to circumscribe educational authenticity. If it is unclear what authenticity is, how are we to understand educational authenticity? What happens if we try to promote authenticity as a curricular subject? Is it possible? This phenomenological investigation grabs ahold of the nature of authenticity and its possibilities and challenges in education. Key questions include, what is authenticity and what makes it unique, what it is related to, and what makes it possible? In relation to learning, to what extent and with what kind of tools can it be promoted in educational institutions? Finally, what are the most promising pathways to investigate authenticity? How can we better understand the human condition through philosophic and human sciences, with authenticity as a metaphor or as a mantra? Here, various methodologies and schools of thought are explored and utilized, including the sociologically based approaches of qualitative research, including autoethnography and post-qualitative methodologies, and philosophic approaches, especially phenomenology. In answering these questions this investigation travels through various fields, methodologies and also, planes in the researcher’s personal life with an aim to establish a personal connection with themes and questions under investigation. The reader is invited to do the same, to connect and disconnect, and to take a stance on what authenticity or doing research means at the moment, but also, what could it mean beyond now. Rather than improving the definitions of authenticity this investigation shows that the beauty and appeal of authenticity lies somewhere else than in its potential for clarifying, measuring or categorizing. Hence, the conclusions for educators do not include programs or steps for authentic education but merely an invitation to employ love and imagination in their own lives and with their students.
  • Allonen, Jaakko (Helsingin yliopisto, 2020)
    Background and aims In recent decades, prognosis amongst acute coronary syndrome (ACS) patients has improved. However, adherence to secondary prevention therapies recommended by guidelines appears insufficient, thereby affecting ACS patients’ survival, particularly in relation to statins. Furthermore, the prognostic benefit of widely used -blockers following ACS, especially amongst low-risk patients, has been disputed. In addition, despite contraindications, ACS patients continue relying upon nonsteroidal antiinflammatory drugs (NSAIDs), which may prove even fatal. Increasingly, guidelines have been unable to establish recommendations for the safe use of red blood cell (RBC) transfusions in an ACS setting. Thus, this study aimed to explore the adherence rates to statins and -blockers as well as the utilisation rate of prescription NSAIDs and their impact on long-term survival amongst ACS patients. Additionally, we sought to determine the effect of RBC transfusion therapy on ACS patients’ long-term morbidity and mortality. Material and methods From 5294 consecutive patients undergoing a coronary angiography (CAG) between 2006 and 2008 in the Genetic Predisposition for Coronary Artery Disease Study (COROGENE), 2090 patients were initially diagnosed with ACS, upon which studies I through IV in this study are based. To assess the utilisation of prescription medications in studies I, III and IV, we obtained data from the Finnish Prescription Register of the Social Insurance Institute (SII) and gathered mortality figures with causes of death from Statistics Finland. In studies II through IV, the Care Register for Health Care (HILMO) from the Finnish Institute for Health and Welfare was used to assess the recurrence of hospitalisations for different reasons. In study II, we merged data on transfusions and haemoglobin (Hb) values from a comprehensive hospital transfusion registry of the Hospital District of Helsinki and Uusimaa (HUS). The primary endpoint in studies I through III was all-cause mortality, whilst in study IV we assessed composite endpoint of recurrent myocardial infarction (MI) and all-cause mortality. Median follow-up was 23 months in study I, 8.6 years in studies II and III and 8.7 years in study IV. Main results In study I when comparing regular statin users (61.7%, n = 1200/1945) to irregular users (33.5%, n = 651/1945) and nonusers (4.8%, n = 94/1945), we observed a stepwise increase in mortality (4.9%, 9.4% and 14.9%, respectively, p < 0.001). The relative risk of mortality was almost threefold higher for nonusers compared to regular users in a multivariable Cox proportional hazards model [hazard ratio (HR) 2.70, (95% confidence interval (CI) 1.49–4.90), p = 0.001]. In study II, we compared RBC transfused patients (4.4%, n = 85/1937) to nontransfused patients (66.0%, n = 1278/1937). RBC transfused patients exhibited a worse long-term prognosis considering both absolute mortality (58.8% vs. 20.3%, p < 0.001) and an adjusted multivariable Cox regression model [HR 1.91 (95%CI 1.39–2.63), p < 0.001]. After matching 65 patients from each group in a 1:1 fashion based on their propensity score, results remained rather consistent [HR 2.70 (95%CI 1.48–4.95), p = 0.001]. The inverse probability treatment weighted (IPTW) model further confirmed our results [HR 2.07 (95%CI 1.38–3.11), p < 0.001]. In study III, we assessed adherence to -blockers separately for each yearly period of follow-up and examined adherence as a time-dependent variable in the Cox proportional hazards model. In a multivariable model adjusted for the concomitant use of other secondary prevention medications, nonadherence to -blockers associated with an increased risk of mortality for both overall survival (OS) [HR 1.84 (95%CI 1.51–2.24), p < 0.001] and on one-year landmark survival (1YLS) [HR 1.74 (95%CI 1.41–2.14), p < 0.001]. The effect on all-cause mortality was also seen within the low-risk patient subgroup [HR 1.60 (95%CI 1.16–2.21), p = 0.004]. As many as 54.3% (n = 1042/1919) of patients filled at least one NSAID prescription during the entire follow-up period in study IV. Yearly use, defined as ≥1 prescription filled per year, decreased slightly from a peak of 22.4% during the second year to 14.5% during the eighth year of follow-up. Current use of NSAID (4.6%, n = 88/1919), defined by the number of days’ supply for the most recent prescription filled lasting up to at least 30 days before the outcome event, was associated with an increased risk of a composite outcome in a mutltivariable adjusted logistic regression model [OR 1.75 (95%CI 1.10–2.78), p = 0.019]. However, we observed no difference in the absolute rates of the composite outcome when comparing current users with nonusers (53.4% vs. 48.5%, p = 0.368). The finding was repeated in the multivariable analyses amongst low-risk patients [OR 2.03 (95%CI 1.19–3.48), p = 0.010]. Conclusions The risk of mortality appears to incrementaly rise with the level of nonadherence to statins amongst ACS patients. Nonadherence to -blockers also associated with an increased risk of death, even beyond the first year following an ACS event. Furthermore, low-risk patients also appear to benefit from continuous -blocker therapy. Alarmingly, despite contraindications many ACS patients continue using prescribed NSAIDs and their use associated with an increased risk of recurrent MI and death. Finally, RBC transfusion associated with a poorer prognosis amongst ACS patients, even during long-term follow-up.
  • Virta, Leena (Helsingin yliopisto, 2020)
    During the ongoing rapid environmental change, different aspects of biodiversity and its effects on ecosystem functioning need to be resolved. A lot has already been learned regarding the value of biodiversity, but due to the complexity of natural environments many aspects are still unresolved, especially about the patterns and effects of microorganismal diversity in marine and brackish environments. This is surprising, given that microorganisms play key roles in many ecosystem functions and the marine microorganisms are estimated to, e.g., provide the majority of Earth’s oxygen. To facilitate better understanding, studies conducted along large gradients and considering the functional diversity of communities can be useful. Large gradients provide insights into the variation of ecological patterns relative to the environment and can indicate the consequences of environmental change on community responses, and the functional diversity may describe the community characteristics and diversity-ecosystem functioning relationships more effectively than taxonomic diversity and allow the generalizations of results between organisms and ecosystems to be made. In this thesis, biodiversity patterns of benthic diatoms, a highly diverse and productive microorganismal group in all aquatic systems, were resolved along different environmental, spatial and temporal gradients in the coastal ecosystems of the Baltic Sea. Being one of the world’s largest brackish water ecosystems with a naturally strong gradient of salinity and climate and with a unique mixture of marine and freshwater species, the Baltic Sea provides an ideal platform for biodiversity research. Biodiversity patterns resolved here included analyzing the effects of benthic diatom diversity on ecosystem productivity, investigating spatial and temporal beta diversity patterns, i.e. the change in community composition between sites or sampling occasions, and examining the effects of environment on the distribution and diversity of diatoms. All studies were conducted as field studies to increase knowledge on real-world processes. The results revealed some significant new insights and showed that the diversity, especially functional diversity, of benthic diatoms may set the lower boundary for ecosystem productivity. Thus, productivity could be high even when the diatom diversity was low, but high diatom diversity seemed to consistently support high productivity. This positive relationship may be due to several reasons, such as more complete resource use or the facilitative effect in diverse communities, or complex ecological interactions. However, the diversity of diatoms varied substantially among different habitats, highlighting the need to consider environmental heterogeneity and large environmental gradients in biodiversity research. Spatial beta diversity studies conducted at different spatial scales indicated a general pattern: across steep environmental gradients, the taxonomic beta diversity was consistently high while the functional beta diversity remained considerably lower. This suggests that the ecosystem requirements for the functional characteristics of microphytobenthic organisms are highly similar in different environments, and that diatoms are able to meet these requirements in variable environments, which may indicate an insurance effect against environmental change. However, simulated species loss of communities significantly increased the functional beta diversity, suggesting that the deterioration of diversity may decrease resilience, and thus emphasizing the importance of biodiversity for the stable functioning of benthic ecosystems. Despite some similarities in the environmental drivers of diatom communities in different environments, environmental variables controlling the communities varied between and within gradients. Thus, the effect of environment on communities seems to be context-dependent and variable between regions, which emphasizes the need for large-gradient studies and the consideration of region-specific differences in, e.g., environmental management and conservation efforts. The seasonal and inter-annual variation in the composition and diversity of communities was investigated along a temporal gradient of two years. The taxonomic and functional composition of communities changed significantly between seasons and years, while diversity remained fairly stable. This refers to either an ample seed bank, i.e. locally occurring resting stages of species, or a large regional species pool and effective dispersal of species, which rescue the populations. However, diversity decreased during an exceptionally warm winter with a short ice-cover duration, which may suggest that climate warming affects the diversity of benthic communities. To conclude, this thesis has increased the knowledge on the diversity and importance of benthic diatoms in complex real-world environments. Some of the diversity patterns were general and non-dependent of spatial scale, whereas others were highly variable between regions and gradients. The results emphasize the need to consider the effect of benthic diatoms when modelling and designing the management of coastal areas, and indicate the usefulness of studies with environmentally and spatially large gradients for the understanding of diversity patterns in natural ecosystems.
  • Yurayong, Chingduang (Helsingin yliopisto, 2020)
    The present study investigates the use and development of demonstratives that follow head word, postposed demonstratives, which are characteristic of eastern Finnic and North Russian dialects. Some previous studies regard these postposed demonstratives as definite articles, while other recent studies identify additional functions related to information structure and discourse. Given that postposed demonstratives are not a feature common to all East Slavic languages, several studies propose that this characteristic feature of North Russian could have resulted from language contact with the Uralic-speaking population who adopted Russian as their second language, particularly Finnic speakers. The main goal of the present study is to answer three research questions: 1) How do postposed demonstratives function as grammatical markers? 2) What does the development of demonstratives tell us about the history of Finnic and Slavic languages? 3) Do postposed demonstratives result from a Finnic substratum in North Russian dialects? For this purpose, the present study examines spoken language data comprising thirteen Finnic and two North Russian varieties which have been in contact during the latest millennium, as well as Novgorod birch bark documents from the 11th–15th centuries. The typological analysis identifies properties and functions of postposed demonstratives from various perspectives: word order, host attachment, syntactic and pragmatic functions. The analysis also combines results with geographical data, which shows the correlation between the speaking areas and linguistic similarities among varieties. The results achieved in the present study justify the following conclusions. First, postposed demonstratives function as grammatical markers with a basic function to organise information structure. At the same time, the properties of information-structural uses as topic and focus markers have secondarily extended to contexts of use in which postposed demonstratives co-occur with definite referents, and are used to code the speaker’s evaluation. The functional extension is particularly common in North Russian dialects and adjacent Finnic varieties in the east. Second, the development of demonstrative systems from Proto-Finnic to modern Finnic languages is influenced by later contacts among Finnic sub-branches that share areal features. Based on these isoglosses, the Finnic demonstrative system can be classified into four groups: 1) western Finnic (Livonian, South Estonian, and North Estonian), 2) central Finnic (Votic and Ingrian), 3) Karelian Finnic (Olonets Karelian and Northern Lude), and 4) eastern Finnic (Southern Lude and Veps). Third, the postposed demonstrative “-to” and its variants in North Russian dialects do not result from the Finnic substratum, but from the adstratum. Through mutual reinforcement with the Veps demonstrative “se”, the indeclinable “-to” inherited from the Central dialect of Middle Russian has developed further properties to inflect and co-occur more often with definite referents. Such a developed pragmatic use later also spread to Lude and Olonets Karelian.
  • Peltomäki, Isto (Helsingin yliopisto, 2020)
    Abstract Suffering is an inescapable part of life. However, how to view and attempt to relieve suffering is an ethically fraught question. The ways to relieve mental suffering are based on conceptions regarding the phenomenon: the origin of suffering, the experience of suffering and the means of relieving or becoming liberated from it. This study attempted to answer three research questions: 1. How is suffering relieved in the church (Evangelical Lutheran Church of Finland) and on what conceptions of suffering is this relief based? 2. What does the church teach about how its Christian members should offer help to their suffering neighbours? 3. How should suffering be relieved morally? I explored the understanding of suffering represented by the church indirectly by studying its practice of pastoral care, which is, by its definition, the practice of relieving suffering. This conceptualisation of pastoral care rests on studies of historical theology that view pastoral care as the Christian tradition of mental help, which connects, in terms of the history of ideas, to the general tradition of mental help and therapy. The aim was not to construct an exhaustive theology of the pastoral care practised by Christians that explains all the religious meanings suffering and its relief could embody. Instead, I focused on the core theology of such pastoral care by conceiving its sufficient and necessary conditions. Thus, I concentrated on exploring and shaping the kind of theology that should be shared within the whole church, and, for this reason, the theology and pastoral care of revivalist movements were excluded from this study. Instead of forging a normative theological scheme of suffering and pastoral care, the study aimed to describe the understanding of suffering that steers the relief of suffering in practice and its possible historical change. Nevertheless, to answer the third research question, by investigating suffering as an ethical question, I proposed a normative conclusion on the kinds of religious or other meanings that should not be attributed to suffering or its relief. The church teaches that pastoral is the task of all Christians. This teaching is founded on Luther’s theology regarding the so-called universal priesthood, which states that conveying and realising the gospel is not only the task of ordinated priests but also the responsibility of all Christians. Based on the idea of a universal priesthood, Christians are called upon to act as providers of pastoral care in their everyday lives and not only within the activities of their particular parish. For both priests and other Christians to act as providers of pastoral care, Luther required that this help concentrate on conveying religious content and meanings. For a Christian, this would mean comprehending the religious meaning of suffering and its relief, which I term Christian subjectivity. Here, the question was whether it is conceivable to expect this kind of Christian subjectivity from members of the church today in order for them to be seen as providers of pastoral care in their everyday lives. I approached this problem by concentrating on the history of the theology of pastoral care through an exploration of the kind of understanding of suffering present in the church today and how it relates to the question of what the church teaches about how parishioners should offer help to their suffering neighbours. In order to achieve the aims of the study, multiple theological and philosophical methods were required. In exploring Luther’s theology, on which the Lutheran interpretation of pastoral care as the common task of all Christians is based, I exploited regressive systematic theological analysis, which aims to provide a conceptual explanation of a particular issue. I also investigated the history of the theology of pastoral care from the Reformation until the present day, concentrating on the theological ideas and conceptions that define the way pastoral care is practised. To explore the change in religiosity revealed by the history of the theology of pastoral care, I utilised studies on the history of ideas, the sociology of religion and the philosophy of religion. In the last part of the study, I concentrated on pastoral care as a philosophical and moral question. Using moral philosophical analysis, I constructed normative arguments on how suffering should be viewed and how it should be relieved. I employed qualitative empirical data to uncover how pastoral care is or could be performed by Christians in their everyday lives. I interviewed six parishioners and three priests. The data was analysed using a three-stage model: a description of the interviews, followed by an inductive and abductive analysis. The interviews offered insight into the help and support offered by parishioners to their relatives, close friends and acquaintances, the kind of values that steer their stance on offering help and support, and the way Christian belief relates to that stance. I explored the pastoral care practised by Christians as religious action and part of their religiosity. When defining religiosity, I exploited the idea of lived religion, which views religiosity as a construct of the conceptions, beliefs and actions represented by Christians themselves. In answer to the first and second research question, the analysis of the history of the theology of pastoral care indicated that Luther’s theology and understanding of suffering cannot be, and, in fact, has not been, adopted by the present-day church. This is because Luther constructed his theology of suffering within a strong climate of religiosity, where the existence of God was considered self-evident. By contrast, contemporary religiosity is characterized by secularisation and so-called disenchantment. Instead of Luther’s theology on suffering and the ways to relieve it, the present-day church has adopted a therapeutic approach to pastoral care. The contemporary pastoral care and relief of suffering shaped by the therapeutic approach appears fundamentally as moral action. This approach to and understanding of suffering are shaped by connections to so-called socially oriented Lutheranism, which characterises the contemporary church as a people’s church. In socially oriented Lutheranism, social action and functions based on loving one’s neighbour are understood to be means of conveying and realising the gospel. The interviews with parishioners revealed a religiosity that lacked the sense of Christian subjectivity that Luther required and held as a principle for Christian life. The historical development of ideas, namely disenchantment and the process of secularisation, explain how contemporary Finnish religiosity is formed. Studies of the Christian beliefs and practices of contemporary Finns indicate that the church cannot adopt the idea of Christian subjectivity to define its theology regarding religiosity and religious action if it wishes to maintain the idea of a people’s church. This idea demands that the theology of Christians and their religiosity must to be formulated to concern and involve all Christians who are members of the church. To answer the third research question, I examined the relief of suffering as a moral action through the concept of love. Further, I studied love as moral action with the concepts of recognition, agency, gift, reciprocity and otherness. I defined love as action based on respecting the agency and otherness of the other, in which relieving suffering is a morally fraught task. Moral action, which is based on respecting agency, requires love offered as a gift that fulfils the condition of reciprocity, where the giver does not regard herself only as a giver and the other only as receiver. This kind of love is based on time-love, not agape, the self-giving mode of love that has traditionally been held as the highest form of love in Christian teaching. To respect the object of love as a moral agent presupposes moral action to be worthy, which is based on the idea that the receiver of gifts could reciprocally give and become a giver. For action and love to be morally successful in terms of relieving suffering, suffering must be taken seriously. No attempt should be made to offer metaphysical explanations for suffering or claim that it fulfils some purpose. All theodicy-explanations should be rejected and, thus, antitheodicy should be adopted as the moral principal for adopting a stance on the suffering of other people. The present therapeutic pastoral care schema follows the antitheodicean approach to suffering. In a contemporary society characterized by disenchantment and secularisation, religious-oriented care, which focuses on explicitly conveying of gospel, is no longer an adequate way to relieve suffering. This is the background and motive for the adoption of the therapeutic approach that I term the therapeutic turn. The therapeutic turn embodies the idea of taking the experience of suffering seriously, and today’s pastoral care practices have been formed on this basis. An antitheodicean stance on suffering does not prohibit processing the meaning of one’s own suffering, but it does deny the moral right to explain the suffering of others by offering reasons for how suffering could in some way be viewed as positive or beneficial. Those who practise pastoral care as employees of the church must commit to promoting the good of a suffering other. Regarding the pastoral care practised by Christians in their everyday life, the normativity of the antiteodicean stance on suffering means that a lack of understanding of the religious significance of their moral action should not be seen as a problem. Instead, the absence of religious meanings can contribute to the kind of practice of relieving suffering that is not based on the compulsion to promote the religious good of the other. Love must be free and target the good of one’s neighbour. The manifold functions of pastoral care are described by two traditional concepts. Cura animarum generalis refers to general pastoral care performed in the pastoral work of church employees. By contrast, cura animarum specialis denotes pastoral care provided for those individuals in special need, such as prisoners and the sick. The idea of the pastoral care practised by all Christians, which is seen as part of general pastoral care, has received little attention. In addition to traditional concepts of pastoral care, we could establish a term for everyday love, caring and the relief of suffering by all Christians: cura animarum mundana. The key consideration that guides the conclusions of this study is the contextual nature of religiosity. The theological conceptions and practices of the church have always been constructed from the prevailing conditions that determine religiosity at a given time. The contextual nature of the principles that define how pastoral care is practised become more obvious and important in the pastoral care practised by Christians. The sufficient and necessary conditions for pastoral care practised by Christians must be formed in accordance with the conditions that determine how members of the church manifest their religiosity. Pastoral care as the practice of relieving suffering is both moral action and also part of lived religion, which is theologically founded on the religious meanings that Christians themselves attribute to suffering and its relief. Key words: Pastoral care, suffering, love, pastoral theology, Lutheran theology, Lutheran ethics, theological ethics.
  • Zhang, Junfeng (Helsingin yliopisto, 2020)
    The mindset has been one of the most debated topics in educational and psychological setting today, but little is known how the cultural differences are associated with the perceptions and how they are related to individuals' behaviours patterns in a cross-cultural context. This dissertation examines mindsets in learning among Chinese and Finnish students and teachers. It comprises four sub-studies. The theoretical study (Study Ⅰ) explores the role of mindset in learning among students and teachers by means of synthesising and compiling previous relevant literature. The three empirical studies II, III and IV, which are based on data collected from teachers and students, focus on how mindsets affect patterns of academic behaviour. Study Ⅱ investigates the ways in which the mindsets of students predict their academic achievement by influencing the factors to which success is attributed. Study Ⅲ examines the giving of peer feedback among adolescents at school, and how the feedback affects students’ mindsets and their academic motivation to learn. Study Ⅳ explores the relations between teachers’ mindsets and their pedagogical strategies. All three empirical studies adopt a comparatively cross-national perspective, namely comparing Chinese and Finnish participants. The literature review is based on twenty-two articles published between 1998 and 2017 focusing on the association between mindset and academic achievement. The three empirical studies that follow are based on data collected from 1,862 students and 127 teachers in two Chinese and two Finnish state schools. More specifically, Study Ⅱ, which is based on Dweck’s mindset inventory and Weiner’s attribution scales, was conducted in one Chinese (N = 705) and two Finnish (N = 495) middle schools. By means of multiple-group structural equation modelling (SEM), Study Ⅲ investigates the influence of peer feedback on mindsets and academic motivation among fourth-to-ninth-grade students. Finally, Study Ⅳ explores the mindsets of selected Chinese and Finnish teachers and their pedagogical strategies from the perspective of praise and goal orientation. It could be inferred from the literature review that students’ mindsets drive, mediate or even generate academic achievement, whereas among teachers the mindset merely drives and mediates. The non-correlation between mindset and academic performance reported in some studies also deserves attention. According to empirical investigations comparing Chinese and Finnish participants, the affecting processes and causal mechanisms indicate both culture-invariant and culture-dependent features. In line with the culture-invariant results: 1) All students have a growth mindset, and attribute their academic achievements to effort and ability, with an emphasis on the former; 2) Person praise given by students to their peers reflects their fixed mindset and negative academic motivation, whereas process-related praise undermines negative academic motivation; 3) All teachers have a growth mindset. With regard to culture-dependent aspects: 1) Chinese students do not differentiate between the concepts of intelligence and giftedness as clearly as Finnish students do, and their emphasis on effort significantly accounts for higher language-related grades, whereas Finnish students with fixed mindsets about giftedness achieve higher grades in mathematics; 2) Chinese students prefer to give process-related and person praise, the former reflecting not only their growth mindset but also their positive academic motivation, whereas Finnish students favour neutral praise and have stronger negative academic motivation; 3) Chinese and Finnish teachers differ in their preferred pedagogical strategies even though they have the same growth mindset, such that Finnish teachers utilise growth-mindset pedagogy whereas Chinese teachers seem to apply mixed strategies reflecting both growth and fixed mindsets. This theoretical review, which is part of the current study, is the first to explore the role of mindsets in learning, thereby enriching the existing research. The empirical studies give constructive suggestions concerning how educators could support the intellectual development and academic growth of learners. Teachers and parents should foster a growth mindset in children and encourage them to value effort and to give process-related feedback to their peers. Thus, it is not enough merely to teach mindset theory at schools. It is equally important to design educational interventions concerning the attribution of performance and giving praise to peers. The need for training in mindset theory and pedagogical intervention also applies to pre-service and in-service teacher education.
  • Assmuth, Aino (Helsingin yliopisto, 2020)
    Forests play a vital role in mitigating climate change, as they sequester and store large quantities of carbon. This dissertation examines how carbon storage may be increased by changing forest management at the stand level. To extend the economics of forest carbon storage beyond single-species even-aged stands, this dissertation develops a bioeconomic model framework that incorporates the size and species structure of the stand, and the optimal choice between continuous cover forestry and forestry based on clearcuts. The studies apply empirically estimated growth models for boreal conifer and broadleaf tree species. The dissertation consists of a summary section and three articles. The first article presents an analytically solvable economic model for timber production and carbon storage with optimized management regime choice between continuous cover and rotation forestry. Continuous-time optimal control theory is utilized to solve the thinning path and the potentially infinite rotation age: if no optimal finite rotation age exists, thinnings are performed indefinitely while maintaining continuous forest cover. The second article extends this model by applying a size-structured growth model for Norway spruce (Picea abies (L.) Karst.), road-side pricing of sawlog and pulpwood, variable and fixed harvesting costs, and several carbon pools. The timing and intensity of thinnings, the rotation age, and the management regime are optimized numerically. In the third article, the optimization approach of the second article is extended to mixed-species size-structured stands. Species mixtures include the commercially valuable Norway spruce and birch (Betula pendula Roth and B. pubescens Ehrh.), and other broadleaves (e.g. Eurasian aspen, Populus tremula L., and maple, Acer sp.) that have no market value. Optimal rotation age is shown to either increase or decrease with carbon price depending on interest rate and the speed of carbon release from harvested wood products. Given empirically realistic assumptions, carbon pricing increases the rotation period and eventually causes a regime shift from rotation management to continuous cover management. Hence, carbon pricing heightens the importance of determining the management regime – continuous cover or rotation forestry – through optimization. Optimal thinnings are invariably targeted to the largest size classes of each tree species. Carbon pricing postpones thinnings and increases the average size of harvested and standing trees, hence increasing mean stand volume. Without carbon pricing, commercially non-valuable other broadleaves are felled during each harvesting operation. When carbon storage is valued, some of the other broadleaves are retained standing until they are large, thus increasing tree species diversity and deadwood quantity. The results suggest that moderate carbon price levels increase timber yields, especially of sawlog that may be used for long-lived products. Increasing carbon storage through changes in forest management is shown to be relatively inexpensive, and the marginal abatement cost is the lower, the higher the number of tree species in the stand.
  • Holkeri, Arttu (Helsingin yliopisto, 2020)
    Sudden cardiac death (SCD) is one of the leading causes of death in the world, accounting for up to 5-20% of all deaths. The vast majority of SCDs are caused by coronary heart disease. However, current clinical risk assessment tools are unable to identify a large portion of subjects at risk for SCDs, as in up to 30–50% of SCD cases, it is the first clinical manifestation of the person’s underlying cardiac disease. The objective of this thesis was to examine the use of electrocardiographic markers in the risk prediction of SCD and other cardiac events in the general population. We used a novel method to digitize and digitally assess the paper electrocardiograms (ECGs) of 7217 Finnish adults participating in a health survey, who were followed for over 30 years. The used paper-to-digital ECG conversion and digital measuring process demonstrated strong agreement with manual ECG assessment in the basic interval and amplitude measurements, although some inter-method differences were noted on QT interval assessment as well. Negative U-waves were present in 3.5% of the general population subjects and independently associated with an increased risk of death. Moreover, among men, negative U-waves predicted also cardiac death and hospitalization due to cardiac causes, whereas among women negative U-waves did not associate with an increased risk of cardiac events. Negative U-waves did not independently associate with an increased SCD risk. Early repolarization (ER) was present in 11.1% of subjects aged <50 years and 12.8% of subjects aged ≥50 years. In subjects <50 years, ER was linked to an increased SCD risk, while among ≥50-year-olds ER did not associate with adverse prognosis. ER in women <50 years associated with a four folds higher SCD risk compared to the absence of ER, while in men <50 years the presence of ER did not demonstrate an increase in SCD risk. Five of the 12 assessed ECG abnormalities independently associated with SCD risk. The cumulative number of these 5 ECG abnormalities, heart rate >80 beats per minute, PR duration >220 ms, QRS duration >110 ms, left ventricular hypertrophy, and T-wave inversion, predicted an increasing SCD risk. The presence of ≥3 of the 5 ECG abnormalities associated with an over 10-folds SCD risk compared to the absence of ECG abnormalities. The use of the cumulative number of ECG abnormalities in risk prediction improved the discrimination of low and high SCD risk subjects. To conclude, electrocardiographic markers provide important information about the prognosis of general population subjects. With better risk prediction, the management of general population subjects could be improved by directing diagnostic assessments and medical therapies to high-risk subjects, to ultimately improve their prognosis.
  • Saarinen, Aino (Helsingin yliopisto, 2020)
    In the recent years, a decline in Finnish students’ learning outcomes has been reported in several investigations, such as in the Programme for International Student Assessment (PISA) and in the Trends in International Mathematics and Science Study (TIMSS). Further, variance in learning outcomes between students coming from different backgrounds has increased in Finland. This dissertation investigated (i) whether self-directed learning practices, use of digital learning materials at school, and participation in early education and care (ECEC) are associated with students’ learning outcomes at 15 years of age and (ii) whether these associations are modified by students’ background factors. The participants (N=5660, 5037, and 4634 in Studies I‒III) came from the Finnish PISA 2012 and 2015 datasets that constitute a representative sample of the Finnish 15-year-old students. Learning outcomes in reading, mathematical, and scientific literacy and collaborative problemsolving were evaluated with a comprehensive set of standardized tests. The frequency of learning practices (student-oriented, inquiry-based, and teacher-directed practices, and use of digital learning materials at school) were evaluated with questionnaires fulfilled by students. Participation in ECEC was evaluated with age at entry into ECEC. Background factors under investigation included gender, repetition of a grade, truancy behavior at school, family wealth, maternal education, single-parent family, and immigrant status. The data were analyzed with structural equation models that were controlled for age, gender, and parents’ socioeconomic status (the index of economic, social, cultural status). Frequent use of self-directed teaching practices or digital learning materials at school were associated with students’ weaker learning outcomes in several knowledge domains. Instead, frequenct teacher-directed practices were related to students’ higher learning outcomes. Moreover, frequent use of self-directed teaching practices or digital learning materials had more negative impact on students’ learning outcomes in students with (vs. without) risky background. Additionally, participation in ECEC before preschool was not associated with learning outcomes at 15 years of age. This association was not significantly moderated by parental socioeconomic status (as measured with the index of ESCS). At a trend level, the impact of participation in ECEC before preschool was slightly more positive for offspring of parents with high (vs. low) socioeconomic status. In conclusion, some pedagogical practices within the school system, such as frequent use of self-directed learning practices or digital learning material, were found to increase variance in learning outcomes between students coming from different backgrounds in Finland. No evidence was found that participation in ECEC would be related to learning outcomes at 15 years of age or would increase equality between students coming from different family backgrounds.
  • Arsenovich, Tatyana (Helsingin yliopisto, 2020)
    The Large Hadron Collider (LHC) accelerator at CERN will be updated into High-Luminosity Large Hadron Collider (HL-LHC) between 2025-2027, and as a result, all of the LHC experiments have to be upgraded to meet the goals set for high-quality physics data taking. Also the Compact Muon Solenoid (CMS) Tracker will undergo several planned upgrades aimed to improve the characteristics of its detectors without negative impact on physics potential. In the HL-LHC, the level of radiation will increase significantly, thus, the radiation hardness of the detectors should be improved while at the same time also improving their capability of handling the higher amounts of data. The candidate materials and technologies for the development of the detectors need to be reviewed taking the requirements of the HL-LHC data taking into account. The quality assurance of these detectors is of utmost importance to identify possible failures as soon as possible in the design phase and later during the production of the devices. The quality assurance methods should be verified to be able to reliably provide the needed characterisation parameters. In this thesis, the processing of the samples and their characterisation are described from the reliability point of view. Descriptions of processing steps, theoretical models and measurements methods are accompanied by the discussion of possible failures and suggestions how to prevent them. Special attention is put on the impact of the so-called human factor and the importance of knowledge transfer. The purpose of this work is to study the long-term stability of silicon detectors with Al2O3 thin films grown with the Atomic Layer Deposition (ALD) method and implemented as an insulation and surface passivation layer. The test samples for these studies were processed during 2011-2015 in the cleanroom facilities of the Micronova centre for Micro and Nanotechnology by Dr. E. Tuovinen. Electrical characterisation and characteristic measurements with source were performed in 2014-2018 in the Detector laboratory and cleanroom facilities of Helsinki Institute of Physics (HIP). In addition, Highly Accelerated Temperature and Humidity Stress Tests (HAST) like those performed in the HIP Detector laboratory facilities is suggested as a new approach for studies of the long-term stability of the detectors. Electrical characterisation demonstrated good long-term stability of capacitance, depletion voltage and leakage current characteristics of the test samples with Al2O3 insulation and surface passivation layer. The result of the characterisation demonstrates that samples with surface passivation are able to withstand higher bias voltage than samples without such passivation. Characteristic measurements with a Cs-137 source confirmed that the surface passivation with Al2O3 does not affect the general detector performance. Characterisation of single pixel sensors coated with the Al2O3 after the flip-chip bonding demonstrated that the additional ALD run is not harmful for the structure of the detector and does not affect its behaviour. Thus, ALD-deposited alumina coating can be recommended as a material for additional protection of silicon detector structures.
  • Vennerström, Pia (Helsingin yliopisto, 2020)
    Viral haemorrhagic septicaemia (VHS) was isolated for the first time in Finland in 2000 from a Finnish brackish water fish farm farming rainbow trout in net pens in the Province of Åland, Baltic Sea. The efforts to eradicate the disease from the Åland islands were not successful. Epidemical factors, needed for VHS management in viral haemorrhagic septicaemia virus (VHSV) positive brackish water fish farms, were studied in a 3-year project, the results of which are presented in this thesis. The study compared the ability of four different surveillance procedures and three diagnostic tests to reveal whether a fish population was infected with VHSV. The programme that was conducted as syndromic surveillance, where the farmers sent in samples for diagnostics if any signs of possible fish disease were noticed, clearly outperformed the other three programmes, which were based on active surveillance. A real-time reverse transcriptase polymerase chain reaction method proved to be at least as sensitive in detecting acute VHSV infections as virus isolation in cell culture, which is considered the gold-standard method for diagnosing VHSV. An ELISA method was used to test fish serums for antibodies against VHSV and was found to be a promising tool in VHSV eradication, particularly for screening populations during the follow-up period, before declaring an area free of infection. During the epidemics it was a common suspicion wild fish being the most likely source of the reinfections of VHSV in infected fish farms in the restriction area. Wild fish of 17 different species from VHS-positive fish farms were screened for VHSV during 2005-2008. In addition, uninfected wild perch, roach and farmed whitefish were introduced to a fish farm with rainbow trout experiencing a clinical outbreak of VHS. The wild fish did not test positive on any occasion, but whitefish were infected and started to replicate VHSV for a short time. The replication of the virus in whitefish was verified using a new qRT-PCR method that tests separately for positive- and negative-sense viral sequences in infected organ samples. The presence of VHSV in the environment on fish farms or processing plants farming or handling VHSV-positive fish was studied by testing samples for VHSV from wild blue mussels (Mytilus edulis) living in infected fish farms. Sea water and sediment from infected fish farms were also tested for VHSV. Wild uninfected blue mussels were also challenged with VHSV in two different challenge tests. Wastewater from a processing plant was tested before and after disinfection treatment. Blue mussels were not found to be carriers of VHSV on any occasion. Sea water tested positive for VHSV RNA more often during the wintertime when water temperature was close to 0°C and sunlight (UV light) sparse. Most wastewater samples collected before the disinfection treatment were positive for VHSV, but samples collected after disinfection were all negative regarding VHSV RNA. Contacts between the processing plants and the fish farms in the restriction area of VHS were very common during this study. Processing plants are usually the place where fish food and farming equipment are stored, including boats that are used for the daily servicing of the farming localities. According to the results of this study, this contact was considered a major risk for disease spread, especially during the cold part of the year when daylight is also short. Altogether, this thesis compiles the results of a series of studies targeting factors that could affect the infection pressure of VHSV.
  • Hiippala, Kaisa (Helsingin yliopisto, 2020)
    The present doctoral thesis examines the epithelial host-microbe interactions of different Gram-negative commensal bacteria in the human gastrointestinal microbiota, which consists of bacteria, viruses and eukaryotic organisms. Under steady-state conditions, commensal gut bacteria are harmless symbionts co-existing with the host as part of the normal, balanced microbiota and supporting intestinal homeostasis. On the contrary, dysbiotic microbiota with reduced species richness and altered composition is associated with many intestinal and systemic diseases. Constant communication between the microbiota and the host is enabled either by direct contact or secreted effector molecules. During the last decades, the beneficial effects of commensal bacteria on intestinal mucosa, as well as the related molecular mechanisms, have been increasingly investigated. Currently, the research focus is shifting from traditional probiotics to so-called “next-generation probiotics” and their potentially health-promoting molecules, “post-biotics”. In addition to the traditional treatment strategies for intestinal diseases, novel bacteriotherapy alternatives could be utilized to increase the presence or activity of commensal species with immunoregulatory capacity and the ability to enhance the barrier function. First, the colonic mucosal microbiota of pediatric ulcerative colitis (UC) patients was compared to non-inflammatory bowel disease (IBD) controls using colonic biopsies and pyrosequencing. Microbiota richness and diversity did not differ significantly between the UC and control subjects. Compositional microbiota changes were observed in the mucosa of UC patients with increased abundance of Firmicutes and Proteobacteria, especially the family Sutterellaceae, and decreased proportion of Bacteroidetes. Furthermore, the expression of selected host genes related to the barrier function was studied in the UC subjects. Most notably, the expressions of inflammatory cytokine interleukin-8 (IL-8), inflammation marker lipocalin-2 and calcium binding proteins, forming the IBD biomarker calprotectin, were elevated supporting previous findings in the literature. Next, the abundance and prevalence of Sutterella spp., belonging to the family Sutterellaceae that displayed increased abundance in the mucosa of UC patients, were studied using biopsies from IBD, celiac disease (CeD) and non-disease controls. In addition, epithelial interactions of the genus Sutterella were assessed in vitro. A decreasing gradient from the duodenum to the rectum was observed in the abundance of Sutterella spp. in non-disease adult subjects. No difference was detected in the prevalence of Sutterella between pediatric CeD or IBD patients and controls. Sutterella wadsworthensis was able to adhere to mucus, while Sutterella parvirubra had a higher adhesion capacity to enterocytes and showed competitiveness in adhesion against S. wadsworthensis. Sutterella spp. harbor a penta-acylated, less toxic lipopolysaccharide (LPS), which caused only a mild release of proinflammatory IL-8 from the HT-29 enterocyte cell line compared to hexa-acylated Escherichia coli. S. wadsworthensis and its LPS induced a higher IL-8 response in the HT-29 enterocytes compared to the other two species, indicating differences in their proinflammatory capacity. Overall, these findings implicated Sutterella spp. as a highly prevalent, benign gut commensal with mild proinflammatory mucosal interactions. A high-throughput screening method was developed to isolate anti-inflammatory strains from a healthy volunteer who had acted as a donor for fecal microbiota transplantation. In the screening, isolates capable of attenuating inflammation in vitro, i.e. decreasing E. coli LPS-induced IL-8 levels in enterocytes as compared to the LPS control, were considered as potentially anti-inflammatory, and identified using 16S rRNA gene sequencing and finally whole genome sequencing. The majority of the isolates eliciting anti-inflammatory activity belonged to the order Bacteroidales. In vitro epithelial interaction assays studying the Bacteroidales strains revealed no correlation between attenuation capacity and adhesion, indicating that the effect was independent of cell-cell-contact. Furthermore, the culture supernatants of attenuating isolates were also effective in decreasing the LPS induced IL-8 response in enterocytes, which supported our hypothesis concerning the presence of effector molecules. Lastly, one of the Bacteroidales strains isolated from the fecal donor was Odoribacter splanchnicus, which is known as an abundant, short-chain fatty acid producing gut commensal. Bacterial-epithelial interactions of this less studied commensal were assessed in vitro. O. splanchnicus did not adhere to enterocytes or enhance epithelial monolayer integrity, yet the bacterium and its cell-free culture supernatant displayed in vitro inflammation attenuation capacity. Furthermore, the spent medium of the O. splanchnicus strain induced a higher anti-inflammatory cytokine interleukin-10 release in relation to tumor necrosis factor alpha in peripheral blood mononuclear cells compared to O. splanchnicus cells or the E. coli control. Outer membrane vesicles (OMVs) were isolated from O. splanchnicus culture medium. The treatment of enterocyte monolayer with O. splanchnicus OMVs prior to LPS stimulation caused a significant decrease in IL-8 levels. The anti-inflammatory effect was more consistent with OMVs than bacterial cells. Taken together, O. splanchnicus seems to primarily exert beneficial interaction with the host. Commensal bacteria and intestinal gut epithelium are engaged in constant cross-talk mediated by direct cell-cell contact and/or secreted bacterial effector molecules. The delicate balance of mucosal microbiota enhancing the barrier function and keeping the intestinal immune cells alerted at an appropriate level is susceptible to disturbances potentially leading to dysbiosis. In this context, the identification of gut homeostasis promoting bacteria and their metabolites, as undertaken in this study, is a vital part of novel, personalized bacteriotherapy using a defined bacterial cocktail to assist in restoring intestinal equilibrium.
  • Tikkanen-Dolenc, Heidi (Helsingin yliopisto, 2020)
    Background: Type 1 diabetes is a chronic condition with risk of severe long-term complications (cardiovascular disease, diabetic nephropathy, neuropathy and retinopathy) that increase the risk of premature mortality, reduce quality of life and cause a huge economic burden to society. The main cause of death and inability in individuals with type 1 diabetes are cardiovascular events, and it has been shown that diabetic nephropathy is the main driver of the increased risk of cardiovascular morbidity and mortality. Diabetic retinopathy is the leading cause of vision loss and blindness in developed countries. Physical activity has been shown to improve the risk profile of individuals with type 1 diabetes. Consequently, previous cross-sectional data show that lower physical activity is associated with a higher degree of diabetic complications, but the causal relationship is unclear. Aim: The aim of this thesis is to assess how the total amount of leisure-time physical activity (LTPA) and its components of intensity, frequency and duration are associated with the development of diabetic nephropathy, cardiovascular outcomes, diabetic retinopathy and mortality in type 1 diabetes. Subjects and methods: The study subjects of this thesis are participants in the ongoing nationwide, multi-centre Finnish Diabetic Nephropathy (FinnDiane) Study. Currently, more than 5000 individuals with type 1 diabetes have been recruited and thoroughly characterized from all over Finland. LTPA was assessed at baseline by a validated self-report questionnaire. The study design is prospective and observational. Results: The intensity of LTPA was associated with the initiation and progression of diabetic nephropathy. Of the other LTPA components, frequency was also associated with the progression of diabetic nephropathy. A larger amount of total LTPA and its components were associated with lower risk of CVD events during follow-up. Only the association between LTPA frequency and incident CVD remained significant after adjustment for potential confounders. LTPA and all its components were associated with lower risk of all-cause mortality after adjusting for several confounders. However, only the LTPA intensity was associated with cardiovascular death after adjusting for covariates. Also, total LTPA and frequency of LTPA were independently associated with lower risk of mortality in individuals with type 1 diabetes and chronic kidney disease. In addition, frequent LTPA was associated with lower risk of severe diabetic retinopathy. Conclusions: Physical activity was associated with reduced risk of diabetic complications and mortality in individuals with type 1 diabetes. In addition, physical activity also seems to benefit those with diabetic complications – notably, diabetic nephropathy – and appears to be safe.
  • Peltonen, Reetta (Helsingin yliopisto, 2020)
    Background and aims Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide. In Finland, 3,538 new cases were diagnosed in 2018. While the incidence of CRC is generally increasing, the mortality rates have been decreasing in many countries due to reduced risk factors, screening, and advances in pathological diagnostics, surgical techniques, and oncological treatments. Approximately half of all CRC patients develop metastatic disease, and up to 75% of the metastases are diagnosed in the liver. Contrary to many other cancers, even metastatic CRC may be treated curatively, if the metastases are limited and can be surgically removed. Currently, approximately 20–30% of the liver metastases can be resected, but over 50% of the patients develop recurrent disease afterwards. Estimating the prognosis after liver resection is of utmost importance, as identifying the patients with a high risk of recurrence enables adjusting the surgical and oncological treatments accordingly, and thus, improving postoperative survival. The aim of this thesis was to evaluate the prognostic significance of 12 biomarkers measured in serum, plasma, and tissue samples of both the primary colorectal tumors and the liver metastases in patients undergoing curative-intent liver resection for colorectal metastases. Materials and methods Altogether 442 patients who underwent liver resection for colorectal metastases at the Helsinki University Hospital between the years 1998 and 2013 were included in this thesis. The four studies are based on the serum samples from all patients (I–III), the plasma samples from a subset of 168 patients (I), and the tumor tissue specimens from a subset of 111 patients who had both primary colorectal tumors and liver metastases operated on at the Helsinki and Uusimaa Hospital District (III and IV). Serum and plasma samples were drawn before liver resection and approximately 3 months afterwards. Tissue specimens included samples of both the primary colorectal tumors and the liver metastases. The concentrations of carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), and C-reactive protein (CRP) were retrieved from clinical records (I and II). Those of human chorionic gonadotropin β (hCGβ) in plasma, tumor-associated trypsin inhibitor (TATI) in plasma, and matrix metalloproteinase-8 (MMP-8) in serum were measured by time-resolved immunofluorometric assay (IFMA) methods (I and III). YKL-40 (chitinase-3-like protein-1, CHI3L1), interleukin-6 (IL-6), matrix metalloproteinase-9 (MMP-9), and myeloperoxidase (MPO) were determined in the serum samples using commercially available enzyme-linked immunosorbent assay (ELISA) kits (II and III). The expressions of matrix metalloproteinase-2 (MMP-2), MMP-8, MMP-9, and transketolase-like protein 1 (TKTL1) were analyzed in the immunohistochemically stained tumor tissue samples. Clinical data were retrieved from patient records, and information about the dates of death was obtained from the Central Statistical Office of Finland. Survival analyses were performed using the Kaplan-Meier method and the Cox proportional hazards model. Results Postoperatively elevated CEA (>5.0 µg/l) was found to predict shorter disease-free/relapse-free survival (DFS/RFS) and overall survival (OS). Preoperatively elevated CEA associated only with shorter OS (I and II). Pre- and postoperatively elevated CA19-9 (>26 or >37 kU/l) indicated shorter DFS/RFS and OS, but the additional value compared to CEA was limited (I and II). Preoperatively elevated TATI (>13 µg/l) associated with poor 3-year DFS after liver resection in the whole patient cohort, and especially in patients with synchronous liver metastases. Postoperatively elevated hCGβ (>1.0 pmol/l) associated with poor 3-year OS in the whole cohort, and it was a sign of impaired prognosis especially among male patients and those with primary rectal tumors (I). A biomarker panel comprising YKL-40, IL-6, CRP, CEA, and CA19-9 was found prognostic, as patients with 2–5 elevated biomarkers pre- or postoperatively were at an increased risk of recurrence and death after liver resection (II). High expression of MMP-9 in primary colorectal tumors and high preoperative MPO in serum indicated improved prognosis after liver resection. Additionally, the prognostic significance of these biomarkers, as well as that of MMP-2 and MMP-8, were found to depend on the clinical characteristics of the patients (III). High TKTL1 expression in the primary colorectal tumors associated with impaired prognosis after liver resection in patients with synchronous liver metastases, but with improved prognosis in those with metachronous metastases. Similar tendencies were observed concerning the expression in the liver metastases (IV). Conclusions In conclusion, CEA is a useful prognostic biomarker for most patients undergoing liver resection for colorectal metastases. However, about half of the patients do not have elevated serum levels of CEA despite of metastatic disease, and those patients may benefit from measuring other biomarkers. A biomarker panel comprising YKL-40, IL-6, CRP, CEA, and CA19-9 could be used to identify patients at a high risk of recurrence after liver resection already before the operation. MMP-9 and TKTL1 in primary colorectal tumors may serve for assessing whether the patients benefit from liver resection or need more aggressive chemotherapy, but the synchronicity of the liver metastases should be taken into consideration. Elevated preoperative serum levels of MPO indicate improved prognosis, and low levels imply a high risk of recurrence. The prognostic value of MMP-2, MMP-8, MMP-9, and MPO varies according to clinical factors, possibly due to immunological or hormonal mechanisms. The investigated biomarkers provide new information about CRC with liver metastases and increase our understanding of the disease. They help us define the prognosis after liver resection and adjust the individual patients’ treatment accordingly. Thus, they contribute to enabling the best possible care.
  • Rai, Neha (Helsingin yliopisto, 2020)
    Solar UV-B radiation (290–315 nm), UV-A radiation (315–400 nm), and blue light (400–500 nm) regulate multiple aspects of plant growth and development, and these are mediated by different photoreceptors. In plants, UVR8 is described as a UV-B photoreceptor, while cryptochromes (CRYs) are described as UV-A/blue photoreceptors, based on their absorption maxima and action spectra. However, these photoreceptors are also sensitive to other wavelengths outside the wavelengths of maximum absorption. Based on this property, their roles could differ in full-spectrum sunlight than those reported from experiments performed in controlled environments. In sunlight, both UV-B and UV-A/blue photoreceptors are simultaneously activated, and there is a possibility that their signaling pathways interact. However, an interaction between UVR8 and CRYs regulating transcriptome-wide responses remained unexplored. Furthermore, persistent high solar irradiance is often followed by drought in the field, and studies have indicated that UV and drought interact to regulate plant physiological responses. However, an interaction for metabolic and transcript abundance responses has not been well-described. These gaps in knowledge are addressed in my thesis through three main aims: (1) to identify the individual roles of UVR8 and CRYs in the perception of solar UV-B, short-wave UV-A (315–350 nm, UV-Asw), long-wave UV-A (350–400 nm, UV-Alw) radiation, and blue light by plants, (2) to test the interaction between UVR8 and CRYs under solar UV radiation, and (3) to determine if pre-exposure to solar UV radiation could provide acclimation to subsequent drought stress in plants. To achieve the first two aims, I used Arabidopsis thaliana wild type and mutants impaired in UVR8 and CRYs photoreceptors and exposed them to different ranges of wavelengths of solar or simulated solar UV radiation and blue light under optical filters. To achieve the third aim, I used two accessions of Medicago truncatula (Jemalong A17 and F83005-5). I exposed them to solar UV radiation using optical filters and subjected them to drought stress by restricting watering in a factorial experiment. The results indicated that UVR8 mediates the perception of both UV-B and UV-Asw radiation. In contrast, CRYs mediate the perception of UV-Alw radiation and blue light. A further novel finding is that UVR8 and CRYs interact antagonistically to regulate transcriptome-wide responses under UV-B and UV-Asw radiation. My thesis also provides evidence that UV-B+UV-Asw radiation and mild drought can interact positively to trigger acclimation through an increase in epidermal UV screening in the drought-intolerant accession, F83005-5, and through an increase in transcript abundance of CHALCONE SYNTHASE in the moderately drought-tolerant accession, Jemalong A17. Furthermore, all three studies showed a distinct response to solar or simulated solar UV-B+UV-Asw and UV-Alw radiation, suggesting a need to split UV-A into short and long wavelengths for future studies on UV-A radiation.