Dissertations and theses


Digital dissertations and theses from the University of Helsinki. Contains both open access theses as well as metadata records.

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  • Rytteri, Susu (Helsingin yliopisto, 2021)
    Weather conditions are changing due to climate change. Average and extreme temperatures are warming and the variability of weather conditions is increasing. Warming winters shorten snow cover duration. Climate change together with other anthropogenic stressors, such as habitat loss and fragmentation, potentially have drastic ecological consequences. Insects as small, short-lived ectotherms are strongly affected by changing weather. Their complex life cycles make them particularly sensitive to the seasonal changes of weather. In this thesis, I utilised long-term data from two butterfly systems to study the ecological effects of changing weather and their implications for insect conservation. Firstly, metapopulation survey data from 1993-2019 on the Glanville fritillary (Melitaea cinxia) complemented with detailed field monitoring data and experimental data allowed the study on larval biology (chapters I, II). Secondly, mark-recapture data from 2000-2016 on a translocated population of the Clouded Apollo (Parnassius mnemosyne) enabled me to study the effects of weather on dispersal and colonisation in a novel landscape (chapters III, IV). Larval overwintering survival was enhanced by snow cover and late spring onset in an experiment (I). The detrimental effect of snowless overwintering conditions on individual level were not reflected by metapopulation growth in the wild. Instead, metapopulation growth was enhanced by increasing growing season precipitation, which largely determines the larval food availability. Microclimatic variation buffered populations against phenological asynchrony between post-diapause larvae and their host plants in a spring when larvae activated far prior to the onset of host plant growth (II). Larval growth was accelerated by warm microclimatic conditions, but survival was highest in cool microclimates. Flight season weather importantly altered annual dispersal rates of butterflies. Increasing solar radiation and proportion of exceptionally warm days increased emigration rates and shortened residence times in a natal patch (III). I simulated the spatial expansion of a translocated butterfly population in the novel release landscape based on prior estimates of habitat-specific dispersal rates in the source population. Dispersal rates were obtained from a model parameterised in a warm flight season, and consequently the simulated colonisation rates were overestimated in cold flight seasons. Warming flight season weather may enhance insect dispersal and colonisation on high-latitude and –altitude range margins with a potential to accelerate range expansions. On the other hand, increasing annual variation in weather may cause range retractions during years of unfavourable weather. Furthermore, increasingly variable weather makes insect conservation more difficult.
  • Pohjola, Anni (Helsingin yliopisto, 2021)
    Brain arteriovenous malformations (AVM) are rare vascular anomalies in which the cerebral arteries and veins are connected without the normal intervening capillary bed. Most often, in roughly half of the cases, the event leading to diagnosis is intracranial hemorrhage. The second most common symptom is a focal epileptic seizure, leading to diagnosis in one-third of the cases. AVM incidence in the general population is approximately 1/100,000 person-years. The average age for AVM diagnosis is slightly over 30 years, meaning that the disease often affects working-age people. It is also a significant cause of intracranial hemorrhage in children and young adults. The AVM hemorrhage is lethal in, on average, 5–25% of patients. In this thesis we have studied patients in the Helsinki AVM database using the 15D health-related quality of life (HRQoL) instrument and questionnaire data about lifestyle. Our database consists of 805 AVM patients treated in the Helsinki University Hospital Department of Neurosurgery between 1942 and 2014. Of them, 325 patients answered the mailed questionnaire sent in 2016 and comprise the study cohort of this thesis. Our research revealed that after a mean 17.6 years (SD ±12.0 yr) of follow-up the HRQoL of treated AVM patients in general was, when considering the difficulty of the disease, only modestly decreased. Also, most of the patients had been able to return to work. In the multivariate model, the decreased HRQoL of AVM patients was explained by older age, sex (being female), difficult refractory epilepsy, difficult location or structure of the AVM, and more than one hemorrhagic episode. Our results support active AVM treatment in those cases which the procedure can be done safely and the treatment-related risks do not exceed the estimated cumulative rupture risk. Another novel finding from our study cohort was that the prevalence of smokers was significantly higher in AVM patients when compared to a matched general population. The high prevalence, especially during the diagnosis, inspires more vigorous investigation of the role of cigarette smoking in the currently unknown etiology of AVMs. With our final article, we participated in the on-going discussion in the scientific community about the statistical handling of the commonly used functional outcome instrument, the modified Rankin Scale. We showed, using our AVM patient cohort, that the popular dichotomous approach in outcome assessment could significantly bias research results.
  • Sallasmaa, Christa (Helsingin yliopisto, 2021)
    The topic of this thesis is participatory budgeting and its connection to the discussion between neoliberalism and participatory governance in the context of city development. Helsinki started its own model of participatory budgeting in 2018 and has pledged to continue the concept in the future. I examine whether Helsinki’s participatory budgeting has the potential to support the ideologies of neoliberalism or participatory governance. In practice, I am exploring the views from the city government and active members of Helsinki’s neighborhood associations. Neighborhood associations had a significant role in the original participatory budgeting of Porto Alegre. I used interview and qualitative survey to collect my data. Neoliberalism has influenced the inequality between regions and the so-called crisis of democracy. Direct involvement of citizens is seen as a solution to these problems. Neoliberalism and participation have a paradoxical relationship: they have received similar criticism. In participatory governance participation means deliberative decision-making based on exchange of knowledge, but in neoliberalism participation can be a rhetoric tool to cover up actual decision-making or a city branding technique. Porto Alegre’s original model of participatory budgeting is seen as a part of participatory governance, but many of the international models seem to be more compatible with neoliberal ideology. The city government has not reserved enough resources to the participatory budgeting. The execution was rushed and showed signs of rationalization. According to the interview and the qualitative survey, inequality between regions might be the downfall of Helsinki’s participatory model. The active members of neighborhood associations see the benefits of participation budgeting but only from the perspective of certain regions. Currently, Helsinki’s participatory budgeting works better as a branding technique than as a method of decision-making. It seems to be more compatible with neoliberalism than participatory governance.
  • Vilén, Katja-Maaria (Helsingin yliopisto, 2011)
    Tarkastelen 1973-luvulla syntynyttä juutalaislähetystä tekevää Jews for Jesus-liikettä ja sen vastareaktiona 1985-luvulla syntynyttä vastalähetystyötä tekevää Jews for Judaismjärjestöä. Analysoin tutkimuskohdetta modernia amerikanjuutalaisuutta, messiaanisen juutalaisuuden kehitystä sekä toisen maailmansodan jälkeistä juutalaiskristillistä dialogia vasten. Jews for Jesus on Moishe Rosenin perustama messiaaninen juutalainen järjestö, jonka tavoitteena on pelastaa juutalaiset julistamalla heille kristillinen evankeliumi. Jews for Judaism taas on ortodoksijuutalaisen rabbi Bentzion Kravitzin perustama vastalähetystyötä tekevä järjestö, joka on syntynyt vastarintaliikkeeksi juutalaisiin kohdistuvaa lähetystyötä tekeville tahoille. Tutkin järjestöjen välistä konfliktia. Tuon esiin konfliktin taustalla olevat erimielisyydet ja sen, millä tavalla taistelua on käyty. Lisäksi kysyn kuinka kummatkin tahot määrittelevät itsensä ja oman missionsa, ja kuinka kilpakumppanit näkevät toistensa edesottamukset ja motiivit. Rajaan tutkimuksen kohdistumaan yksinomaan Yhdysvaltojen tilanteeseen, mikä on luontevaa, sillä sekä Jews for Jesus että Jews for Judaism aloittivat toimintansa siellä. Keskeisimpiä lähteitäni ovat organisaatioiden omat WWW-sivut sekä Moishe Rosenin juutalaislähetyksen opaskirja ”Witnessing to Jews” ja Bentzion Kravitzin vastalähetystyön käsikirja ”The Jewish Response to Missionaries: Counter Missioanry Handbook”. Monet erimielisyydet koskivat samoja aiheita, joita juutalaiskristillisessä dialogissa on käyty läpi toisen maailmansodan jälkeen. Kysymys, millä tavoin näiden kahden organisaation näkemysten vastakkainasettelu suhteutuu aiemmin käytyyn juutalaiskristilliseen dialogiin, on tutkimuksessani sivukysymyksenä. Käsittelen sivukysymyksenä myös sitä, kuinka tavoin Jews for Jesus suhtautuu kristilliseen sionismiin. Selvittääkseni, miten kampanjaa on käyty käytännön tasolla, olen tutkinut Jews for Jesusin Behold Your God- evankeliointikampanjaa koskenutta uutisointia pohjois-amerikkalaisissa sanomalehdissä vuosina 2001–2006. Tulkitsen suurimpien erimielisyyden aiheiden olleen Jews for Jesusin näkemyksen, että Jeesus oli messias, Jumalan poika ja ihmisten ja Jumalan välinen välittäjä. Myöskään Uudesta testamentista noussut ajatus, että Jeesuksen tuoma uuden liiton täyttymys korvaisi vanhatestamentillisen juutalaisten liiton, ei sopinut juutalaiseen ajatusmaailmaan. Jews for Judaism ei nähnyt syytä, miksi ensimmäinen liitto ei enää olisi voimassa Keskeisimpiä konfliktin syitä oli myös Jews for Jesusin näkemys itsestään juutalaisina ja kristittyinä yhtä aikaa. Jews for Judaismin ehdoton kanta oli, ettei uskontoja voinut yhdistää. Jews for Jesus sai osakseen ankaraa kritiikkiä Jews for Judaismin ja juutalaisyhteisöjen taholta. Heitä syytettiin valheellisen sanoman levittämisestä. Jews for Jesus uskoi, että näillä syytöksillä pyrittiin vain kääntämään ihmisten huomio pois heidän julistamastaan sanomasta. Jews for Jesus syytti Jews for Judaismia siitä, että nämä loivat pelon ilmapiiriä propagandallaan ja saivat sitä kautta rahaa toimintaansa juutalaisilta tahoilta. Tulkitsen, että kumpikin taho halusi pelastaa juutalaiset ja oli valmis taistelemaan heidän puolestaan. Panoksena oli Jews for Judaismilla juutalaisuuden säilyminen ja Jews for Jesusilla juutalaisten kuolemanjälkeinen pelastuminen. Vastapuoli oli lähes demonisoitu suureksi valehtelijaksi. Näistä lähtökohdista käsin yhteentörmäys oli väistämätön ja yhteisymmärrys vaikutti mahdottomalta saavuttaa.
  • Masalin, Senja (Helsingin yliopisto, 2021)
    Gestational diabetes mellitus (GDM) is a common metabolic pregnancy disorder, affecting 1 in 7 pregnancies on a global level. In Finland, the prevalence of GDM has increased rapidly in the recent decades and was 21% in 2018. GDM is a major public health concern, with adverse short- and long-term health implications for the woman and her offspring. Traditional risk factors for GDM include advanced maternal age, overweight and obesity, a family history of diabetes and an ethnicity with a high prevalence of diabetes. There are, however, other risk factors, referred to as non-traditional, that have been shown to increase the risk for type 2 diabetes but have been studied less or with conflicting results with regard to GDM. The aim of this thesis was to evaluate the impact of several non-traditional maternal risk factors (height, body size at birth, smoking status and socioeconomic status) on the risk for GDM. The thesis is part of the register-based follow-up Vantaa Birth Cohort study 2009–2015. Data has been collected from the Finnish Medical Birth Register, the Finnish Social Insurance Institution, the Finnish Tax Administration, and Statistics Finland. In Study I, encompassing 4,111 Finnish primiparous women and their singleton offspring, maternal height was inversely associated with the development of GDM, after adjustments for age and educational attainment (p = 0.018 for linearity). Independently, both maternal height and GDM were positively associated with the birthweight of the offspring (calculated as Z-score according to sex and gestational age; p < 0.001 for both). However, the interaction between maternal height and GDM was significant and an increase in birthweight was noted only in women within extreme height categories, group I ≤ 158 cm (p = 0.011), group IV 168–172 cm (p = 0.010) and group V ≥ 173 cm (p < 0.001). In Study II, encompassing 1,548 Finnish primiparous women, there was a positive correlation between maternal body size at birth (assessed as body surface area [BSA]) and adult anthropometry. The association between maternal BSA at birth and GDM was inverse (p = 0.015 for linearity), after adjustments for age, educational attainment, pre-pregnancy body mass index (BMI) and smoking. In Study III, encompassing 4,111 Finnish primiparous women and their singleton offspring, a positive relationship between smoking during pregnancy and GDM was observed. The prevalence of GDM was highest in the group of smokers who continued smoking after the first trimester, compared with those who quit, and non-smokers (p = 0.004 for differences between groups). In women without GDM, birthweight was lowest in newborns of smokers who continued smoking after the first trimester (p = 0.004 for differences between groups, adjusted for age and pre-pregnancy BMI). In women with GDM, offspring birthweight was not related to maternal smoking. In Study IV, encompassing 5,962 Finnish primiparous women, there was an inverse association between increasing maternal income level and the development of GDM, after adjustments for age, cohabiting status, pre-pregnancy BMI and smoking (p < 0.001 for linearity). Educational attainment also showed an inverse relationship with the development of GDM. In conclusion, maternal current height, BSA at birth, and socioecomonic status (assessed as both income and educational attainment) were all inversely associated with the risk for development of GDM. Further, maternal smoking during pregnancy increased the risk for GDM. Birthweight was lowest in newborns of women without GDM who continued smoking after the first trimester. However, among newborns of women with GDM, birthweight was not related to maternal smoking. Recognizing specific maternal risk factors is important in lifestyle conseling and targeted prevention of GDM. Hence, findings on the non-traditional risk factors evaluated in this thesis indicate they are of importance both from a clinical and public health perspective. However, future studies are needed to confirm the associations, taking possible additional confounding factors into account, as well as to verify the mechanisms behind these associations.
  • Young Kyu, Shin (Helsingin yliopisto, 2021)
    This dissertation examines insecure workers’ union memberships and attitudes towards new welfare programmes. To compare union memberships and policy preferences among different types of insecure workers, this research classifies these individuals into four different groups: part-time employees, temporary workers, low-skilled workers in the service sector, and solo self-employed workers. The first sub-study explores the unionisation of insecure workers by European industrial relations regime by estimating multilevel binary logistic models with the data from the European Social Survey Round 5 (2010). The second one investigates insecure workers’ choices regarding unemployment insurance and union membership after the reform of the Finnish Ghent system in 1992 by analysing the pooled Finnish Income Distribution Survey data from 2000 to 2012. On the other hand, the third and fourth sub-studies to examine insecure workers’ preferences for new social policy ideas concentrate on universal basic income and social investment policy for unemployment, respectively. To address these topics, both sub-studies estimate binary logistic regression models with clustered standard errors and country dummies by using the data from the European Social Survey Round 8 (2016) The first sub-study reveals that insecure workers’ inclination to join a union varies according to their form of employment and the industrial relations regime to which they belong. The second sub-study illustrates that in the transformed Finnish Ghent system, both part-time and temporary employees are inclined to have no union membership, whereas low-skilled service workers do not make significantly different choices from other employees. In addition, the third sub-study shows that only temporary employees tend to have more favourable attitudes among different groups of insecure workers. The fourth sub-study demonstrates that in a budgetary trade-off scenario between social protection and social investment, part-time permanent employees are inclined to be more supportive of social investment policy, whereas part-time temporary workers are less likely to support it. On the other hand, full-time temporary employees and solo self-employed workers do not exhibit significantly different preferences from standard employees.
  • Wang, Ziyu (Helsingin yliopisto, 2021)
    This doctoral thesis examines how young Chinese people experience being and becoming in their education and how their child-parent relationships relationally influence these experiences. Two groups of concepts frame the analysis: first, being and becoming (including temporality, well-being, learner identity and orientations towards future) and, second, the child-parent relationship (including parental involvement, agency and relational influences). This study employs both quantitative and qualitative methods. The data was gathered through a China Family Panel Studies survey (N=1306), individual interviews (N=25) and an open-ended survey (N=479). These data were analysed by various methods, including statistical analysis, qualitative content analysis and thematic analysis. These young Chinese people have experienced multiple ways of being and becoming. The majority juggle being and becoming in a future-oriented way to achieve educational success, while a significant minority focus on the present and on happiness, entertainment and socialising. The findings point to a mix of abundant parental social support (particularly emotional support) and distant, conflictual child-parent interactions in young people’s negotiations of being and becoming. Young people’s agency has diverse forms embedded in their past, present and future family episodes, and they exercise their agency to mediate their parents’ educational involvement. The thesis suggests that the concept being and becoming heightens the entanglement between the present and the future and the intersection of the temporal and the social, which is increasingly recognised when studying youth. This study also demonstrates that a relational perspective is valuable in uncovering the dynamics, nuances and interactions in young people’s living and growing up. These rich descriptions enable further re-envisioning young Chinese people by questioning their traditionally submissive archetype. Such an inquiry into young people’s individual experiences and their interactions with their social context pinpoints ‘the social’ in social work studies at large. This study also draws out implications for educational and career support for young people and relational social work in practice.
  • Penttinen, Jussi (Helsingin yliopisto, 2021)
    HMC is a computational method build to efficiently sample from a high dimensional distribution. Sampling from a distribution is typically a statistical problem and hence a lot of works concerning Hamiltonian Monte Carlo are written in the mathematical language of probability theory, which perhaps is not ideally suited for HMC, since HMC is at its core differential geometry. The purpose of this text is to present the differential geometric tool's needed in HMC and then methodically build the algorithm itself. Since there is a great introductory book to smooth manifolds by Lee and not wanting to completely copy Lee's work from his book, some basic knowledge of differential geometry is left for the reader. Similarly, the author being more comfortable with notions of differential geometry, and to cut down the length of this text, most theorems connected to measure and probability theory are omitted from this work. The first chapter is an introductory chapter that goes through the bare minimum of measure theory needed to motivate Hamiltonian Monte Carlo. Bulk of this text is in the second and third chapter. The second chapter presents the concepts of differential geometry needed to understand the abstract build of Hamiltonian Monte Carlo. Those familiar with differential geometry can possibly skip the second chapter, even though it might be worth while to at least flip through it to fill in on the notations used in this text. The third chapter is the core of this text. There the algorithm is methodically built using the groundwork laid in previous chapters. The most important part and the theoretical heart of the algorithm is presented here in the sections discussing the lift of the target measure. The fourth chapter provides brief practical insight to implementing HMC and also discusses quickly how HMC is currently being improved.
  • Suominen, Henri (Helsingin yliopisto, 2021)
    Online hypothesis testing occurs in many branches of science. Most notably it is of use when there are too many hypotheses to test with traditional multiple hypothesis testing or when the hypotheses are created one-by-one. When testing multiple hypotheses one-by-one, the order in which the hypotheses are tested often has great influence to the power of the procedure. In this thesis we investigate the applicability of reinforcement learning tools to solve the exploration – exploitation problem that often arises in online hypothesis testing. We show that a common reinforcement learning tool, Thompson sampling, can be used to gain a modest amount of power using a method for online hypothesis testing called alpha-investing. Finally we examine the size of this effect using both synthetic data and a practical case involving simulated data studying urban pollution. We found that, by choosing the order of tested hypothesis with Thompson sampling, the power of alpha investing is improved. The level of improvement depends on the assumptions that the experimenter is willing to make and their validity. In a practical situation the presented procedure rejected up to 6.8 percentage points more hypotheses than testing the hypotheses in a random order.
  • Hyvönen, Henri (Helsingin yliopisto, 2021)
    Discussions on care of the self have intensified in Finland over the last thirty years. Self-care discourses are produced, for example, in public discussions in which individuals are motivated to become more responsible for themselves under the assumption that the weakening welfare society is no longer able to support each and every individual through difficult times. Concurrently, ideas about caring for and nurturing the self have increased in commercial value. Employers and numerous commercial actors have started to define the proper way to care for the self and to offer individuals means of self-care. For instance, the promotion of mindfulness exercises to deal with work-related stress, various diets as enhancers of physical activity, and the shaping of personal attitudes in response to increased insecurity in the labor market are ways in which individuals are being challenged to shift their gaze to their bodies and behaviors, and shape them to fit the new demands set by working life. Thus, self-care is not a single, undivided social movement, but the site of a struggle wherein disagreements are constituted between interest groups representing different conceptualizations of the proper care of the self. This dissertation focuses on how men think and talk about their practices of work-related self-care, and the norms and expectations placed on men’s work-related self-care. The first empirical dataset of my study consists of interviews with men regarding their conceptualizations, perceptions, and memories of work-related self-care. The second dataset consists of media data from texts addressing men’s work-related self-care. The context of the present study is post-industrialized working life in Finland, where men’s job opportunities lie increasingly in the knowledge-intensive sector, social services and healthcare, and service-based jobs. The changes in the labor market and the ethical deliberation on self-care in both public discussions and workplaces problematizes those masculinities that have traditionally been idealized in the Finnish socio-cultural context. Many men no longer identify with, and are not expected to identify with, the way of being a man characterized by an ethos of surviving alone, a suspiciousness towards authorities, and a reluctance to monitor one’s own health status and emotions. In line with recent theoretical discussions in critical studies on men and masculinities, my study adopts the concept of hybrid masculinity to depict men’s incorporation of performances and identity elements previously associated with various femininities. By adopting Michel Foucault’s concept of care of the self, the study addresses self-care as a practice that is enabled and constrained by institutions and norms. Theoretically and methodologically, the dissertation draws from poststructuralist theorizations. The results indicate that contemporary men identify with masculinities that include performances and behaviors previously associated with femininities. The participants in my study conceptualized their bodily and mental health as partly imperfect and malleable material, which they wanted to and were able to shape and refine. They associated their way of participating in working life with genderless worker citizenship, in which self-reflexivity, adaptability, and responsibility for the productivity of one’s work are the guiding principles in life. Concurrently, the men in the study aimed to maintain their personal health and wellbeing as well as a balance between work and non-work. As a part of their self-care, they expressed a desire to heal from traditional masculinity. This means an intention to abandon the positive male identity achieved through success at work and sacrificing oneself for work. The media addresses work-related self-care in a way that reproduces persistent discursive interrelations between men and paid work. Media texts present self-care aimed at maintaining or increasing work performance in a favorable light. Personal wellbeing is subordinated to workplace productivity in media texts. The masculinities present in the speech of the participants and the idealized masculinities produced by the media have been hybridized, albeit based on different aspirations and problematizations. The participants prioritized their personal wellbeing and the meaningfulness of their lives in ways that escaped the external pressures placed on them. In contrast, the concerns and aspirations voiced in the media highlighted the idea that men should focus purely on their abilities to work effectively, avoid illness, and aim to prolong their careers. My study reveals tensions in the contemporary developments of masculinities in relation to both men’s health behavior and their ways of participating in working life.  
  • Karimaa, Anna-Elina (Helsingin yliopisto, 2021)
    Pollinator abundance and diversity are declining at an alarming rate around the world, which poses a threat to ecosystem stability and human wellbeing. There are signs that growing pollination deficits are limiting agricultural yields in Finland and globally. More information is urgently needed on how changes in pollinator communities affect crop yields and how adequate pollination services could be achieved across a range of crops and locations. This study explores the effects of pollinator abundance and diversity on caraway (Carum carvi L.) pollination and yield. Caraway is partly wind-pollinated, but insect pollination has been shown to increase its yield. Flower visits of pollinating insects were monitored on 30 caraway fields in southern Finland in summer 2019. Yield samples were collected from open-pollinated plants and from control plants excluded from pollinators. Pollinator exclusion reduced caraway fruit set by 13.2% and seed yield by 39.6%. Fruit set, 100-seed weight and seed yield increased with increasing flower visitation. Pollinator species richness and Shannon index had no significant effect on the yield components, but evenness of the pollinator community had a negative effect on seed yield and the numbers of umbels and umbellets in the caraway plants. The most abundant pollinators visiting caraway were syrphid flies, non-syrphid Diptera and honeybees. Visits by syrphid flies and honeybees increased seed yield, while visits by non-syrphid Diptera, solitary bees and Lepidoptera had no significant effect on the yield components. Flower visits by beetles reduced 100-seed weight. The results show that syrphid flies provide an important pollinator service for caraway cultivation. It would be beneficial to study which syrphid fly species are the most effective pollinators for caraway and how to manage fields and farmland landscapes to increase their numbers. Relying only on managed honeybees to enhance caraway pollination may not be advisable due to their potential negative effects on wild pollinators. While increased pollinator diversity did not improve caraway pollination or yield in this one-season study, it may be important for the stability of pollinator services in long term.
  • Jakkli, Meera (Helsingin yliopisto, 2020)
    Neural Oscillations at large-scale local and global neural synchrony levels can be detected at the scalp using electroencephalography. This neural activity presents itself in a varied range of frequencies referred to as ‘Brain Waves’. These frequency bands have cognitive significance and have been implicated in several neural functions due to its important role in communicating with functionally-similar but spatially-distinct brain regions. Frontal Asymmetry is the difference in activity between the right and left hemispheres in frontal areas of the brain recorded via EEG and is seen to be a strong indicator of emotional states. Specifically, approach and withdrawal motivation which have been associated with positive and negative emotions respectively. Using a combination of behavioural and physiological methods in measuring preference and responses gives us an accurate representation of the participant responses. In this study, three tests were conducted during a continuous EEG recording. Test 1: The implication of inducing a positive mood before the onset of stimulus line-up and the extent of its effect on emotions and alpha asymmetry is not extensively studied. In this test, we employed the use of an instrumental soundscape for one experimental group before beginning the stimulus presentation to test this effect against a ‘silent’ control group. Test 2: This test aims to compare the participants’ physiological measures (EEG) and behavioural self-reports to audio advertisement stimuli consisting of different categories of music: ‘Brand music’ vs. ‘Campaign’ music or ‘No music’ Controls. Test 3: There is ambiguity in research regarding how frontal alpha asymmetry as measured by EEG and self-report preferences might change with changing the format of the advertisement to: only Audio, Audiovisual and Silent videos. There has been contradictory evidence regarding the impact of music on an individual’s emotions and consequent memory and decision-making. This thesis delves into these questions through the post-study behavioural test and simple binary choice paradigm that measure the above-mentioned in relation with the stimuli presented to participants. Our results did not show a significant difference in frontal asymmetry in the stimulus presentation across the three tests conducted during EEG recording. The behavioural data however indicated significant preference in behavioural self-report ratings for Brand Music- associated stimuli in Test 2 and for Audiovisual advertisement stimuli in Test 3. Results also revealed a significant correlation between ratings given to a stimulus and post-study memorability. The final binary choice paradigm test indicated higher preference to products related to stimulus presentation (‘advertised’ brand) vs similar products not related to the presented stimulus (‘non-advertised’ brand). We anticipate that these results will further help us understand and predict general preferences that can help companies, government policy-makers and the general public be more aware and better equipped to manage their valuable resources of money, time, attention and memory.
  • Ruippo, Lotta (Helsingin yliopisto, 2020)
    Innovation in food packaging interlinks many sustainability challenges ranging from food loss and waste through the value chains, to resource extraction and growing amounts of plastic waste globally. Food packaging innovations arising from regulation often focus on material waste and ignore other facets of sustainability such as food loss and waste. Simultaneously, conventional notions of innovations are focused on firm growth and competitiveness. This study investigates the perceptions of sustainability in food packaging among expert actors in Finland. Moreover, it examines how notions of Responsible Research and Innovation (RRI) are reflected in the research and development processes in the field. Here, RRI is understood as a framework for examining the role of socio-ethical considerations in research and development. The study aimed to find out which packaging attributes are considered sustainable, what motivations actors in the field have, what type of obstacles exist to innovation in the field, and which actor groups are perceived to be responsible for accelerating the food packaging transition towards sustainability. Semi-structured expert interviews were conducted with 14 participants, and the interview data were analyzed using qualitative content analysis (QCA). The results show that perceptions of sustainability in food packaging vary across the field. However, reducing food waste and loss was considered the most important facet of sustainability in food packaging. Actors in the field are motivated by personal reasons and the anticipated profitability of sustainable innovations. However, innovations in the field are slowed down because of regulatory issues, food safety requirements, unpredictable future changes, and technological lock-ins. Finally, the results of this study indicate that actors in the sector believe the Finnish government and brand owners in the food and beverage industries should be responsible for driving innovation towards improved sustainability. However, the qualitative approach taken here limits the generalizability of the results. The results suggest an ongoing narrative shift in innovation towards greater inclusion of social and ethical considerations in the research and development process.
  • Riihimäki, Katariina (Helsingin yliopisto, 2021)
    Mafis-ultramafinen Kevitsan intruusio, joka sijaitsee Keski-Lapin vihreäkivivyöhykkeessä Pohjois-Suomessa, sisältää pirotteisen Ni-Cu-PGE-esiintymän. Kairareikä KVX018 lävistää intruusion ja sen pohjakontaktin, ja kairareiästä on havaittu suhteellisen matalan resistiivisyyden vyöhyke intruusion syvimmissä osissa. KVX018 on syvin Kevitsan intruusioon kairattu tutkimusreikä ja havaittu vyöhyke on ainutlaatuinen tutkimusalueella. Aiemmat tutkimukset osoittavat intruusion pohjakontaktin erottuvan seismisissä heijastusluotauksissa ja sisältävän mahdollisesti mineralisaation. Tässä työssä tutkitaan Kevitsan intruusion pohjakontaktin erityispiirteitä KVX018 kairasydämestä, ja tulkitaan matalan resistiivisyyden alkuperää ja sen yhteyttä mineralogiaan. Geokemiallisten ja petrografisten piirteiden perusteella tutkitussa kairareiän osassa (1551-1878 m) havaitaan neljä toisistaan poikkeavaa yksikköä: jalkapuoli (sivukivet), kontaktivyöhyke, alemmat kumulaatit ja ylemmät kumulaatit. Alempien kumulaattien havaittiin olevan voimakkaasti kontaminoituneita hydrotermisiin liuoksiin peruskalliosta liuenneista alkuaineista. Kontaminaatio havaittiin 125 metriä pohjakontaktista ylöspäin kohonneina litiumin, lantaanin, rubidiumin ja kaliumin pitoisuuksina, sekä näiden alkuaineiden ehtymisenä kontaktin lähellä jalkapuolen kivissä. Kontaktivyöhyke on voimakkaasti silisifikoitunut ja albiittiutunut. Hydrotermisten liuosten aktiivisuus pohjakontaktin läheisyydessä havaitaan myös plagioklaasin muuttumisena epidootiksi. Kontaktivyöhykkeessä on kapea mineralisaatio, joka tulkittiin ”false ore”-tyypin malmiksi ja sen sulfidien nikkelipitoisuudeksi laskettiin 2,28 %. Kontaktivyöhykkeestä ylöspäin mineralisaation todettiin ensin olevan heikkolaatuista Ni-PGE malmia ja sen yläpuolella ”normal ore”-tyypin malmia. Ultramafisten intrusiivisten kivien havaittiin olevan muuttuneita amfiboli-muuttumisen tuloksena paikallisesti niin voimakkaasti, että alkuperäistä mineralogiaa ja tekstuureja ei pystytty määrittämään. Muuttumisen intensiteetti voimistuu intruusion pohjaosissa syvemmälle mentäessä. Suolamineraaleja todettiin silmämääräisesti joidenkin näytteiden pinnalla ja röntgendiffraktio-menetelmällä (XRD) yhdessä näytteessä. XRD tulokset osoittivat tutkitun näytteen sisältävän nitratiinia ja sylviittia, jotka ovat evaporiiteissa tyypillisesti esiintyviä suolamineraaleja, ja joiden esiintyminen saattaa viitata evaporiittisten sedimenttien osallistuneen malminmuodostukseen. Kivien resistiivisyyteen vaikuttavat mm. kiven sulfidipitoisuus, suolapitoisuus, huokoisuus ja muuttuminen. Resistiivisyyden ja varautuvuuden havaittiin korreloivan, joka viittaa resistiivisyyden korreloivan myös sulfidimineraalien esiintymisen kanssa. Kuitenkin 680 metrin syvyyden jälkeen resistiivisyys pienenee ilman vastaavaa muutosta muissa petrofysikaalisissa ominaisuuksissa. Tämän tutkimuksen perusteella matala resistiivisyys johtuu suola- ja sulfidimineraaleista, sekä intruusion kivien voimakkaasta muuttumisesta.
  • Imlimthan, Surachet (Helsingin yliopisto, 2021)
    Cancer is a critical health concern worldwide. Although significant progress in cancer diagnosis and therapy has been made to date, the lack of efficient delivery of active compounds to the target site and adverse systemic effects remain a major challenge in cancer treatment. For those reasons, different therapeutic strategies have been developed to improve the target specificity and reduce side effects in conventional therapy. Nanomedicines are innovative nanoparticulate drug delivery systems constructed from biocompatible, biodegradable, and nontoxic materials. Nanoparticles can transport diagnostic and therapeutic agents with increased bioavailability, reduced dosing frequency, and less off-target side effects. Recently, cellulose nanocrystals (CNC NPs) and lignin nanoparticles (LNPs) have attracted attention as abundant natural nanomaterials that can be derived from various bioresources, especially plant-based lignocellulosic biomass. CNC NPs and LNPs have been intensively explored as material scaffolds in numerous biomedical applications due to their unique physicochemical and biological properties. Nuclear molecular imaging techniques, including single-photon emission computed tomography (SPECT) and positron emission tomography (PET) are non-invasive and sensitive imaging technologies that allow the tracking of a tracer dose of radiopharmaceuticals in vivo to determine their target occupancy, circulation, biodistribution profiles, and elimination kinetics. Nanomaterials tagged with a radioactive label can be traced after systemic administration through the detection of gamma photons emitted by the radioactive isotopes outside the body (single γ photon for SPECT and annihilation of two anti-parallel 511 keV photons for PET). Moreover, several radioisotopes can concomitantly release diagnostic γ radiation and ionizing particles (α or β-) during their decay, enabling the consolidation of diagnostic imaging and radiotherapy. The combination of imaging labels and therapeutic agents into a single nanoparticle platform creates a theranostic nanosystem, which can be used for simultaneous imaging and therapy of cancer. This thesis aimed to develop theranostic nanoparticle drug delivery systems based on CNC NPs and LNPs. The project comprised of several studies: 1) radiolabeling chemistry development, 2) in vitro cytotoxicity and cellular uptake investigation, 3) in vivo biodistribution and imaging studies in tumor-bearing animal models with the developed tracers, and 4) a theranostic nanosystem development and biological evaluation based on the observations from 1–3. Firstly, CNC- and LNP-based imaging probes for nuclear and optical imaging were developed for the in vitro and in vivo investigation using two modification strategies: site-specific hydrazone linkage to the terminal aldehyde of the CNC and non-site-specific conjugation using CDI activation. Both multimodal CNC NPs and LNPs demonstrated low cytotoxicity and favorable interactions with macrophage and cancer cell lines. Following extensive validation in material characterization and in vitro cell models, radiometal chelator DOTA-modified CNC NPs from both synthetic pathways were selected to further explore the in vivo behavior through the labeling with diagnostic radionuclide 111In in both healthy and 4T1 breast tumor-bearing mouse models. The ex vivo biodistribution and SPECT/CT imaging revealed comparable pharmacokinetic profiles where the accumulation of all developed 111In-labeled CNC NPs was primary in the lung, liver, and spleen, which are the clearance organs of nontargeted nanoparticles. Due to high retention of the CNC in the lung capillaries, theranostic CNC NPs were further developed for co-delivery of radiotherapeutic 177Lu and chemotherapeutic vemurafenib to target YUMM1.G1 metastatic melanoma in the lung through vascular trapping. The theranostic CNC NPs exhibited excellent radiolabel stability and sustained drug release profiles in vitro. The therapeutic studies also showed that the lifespan of tumor-bearing animals treated with theranostic CNC NPs was increased about twice from the median survival time of animals receiving only the vehicle or CNC NPs carrying only a single component of the theranostic system. In conclusion, the work presented in this thesis demonstrates the successful development of novel CNC- and LNP-based molecular imaging nanoprobes and the theranostic CNC NPs for the delivery of radio- and chemotherapeutic agents with enhanced therapeutic efficacy compared to the conventional chemotherapy in metastatic melanoma. The studies provide a breakthrough on the development of systemically administered CNC drug delivery systems and warrant further investigation on the potential of CNC NPs as a renewable scaffold for theranostic drug delivery systems.
  • Halonen, Roope (Helsingin yliopisto, 2021)
    Nucleation of liquid, or solid, clusters in the gas phase is ubiquitous in nature. It plays a major role in various fields of studies, and especially those dealing with the atmosphere and climate change. A significant portion of atmospheric particles is formed through nucleation, and these small particles can affect the climate by either absorbing or scattering sunlight, or acting as seeds for cloud formation. On the other hand, nucleation can also be used in technologies aiming at climate change mitigation: e.g., a novel nucleation-based approach using supersonic separators for CO2 capture provides an environmentally friendly alternative to traditional approaches involving toxic compounds. Despite the fact that nucleation has been studied for over a century, the theoretical picture remains incomplete. In the context of this thesis, nucleation is determined by kinetics and thermodynamics as special attention needs to be paid to the phase and energy of the nucleating clusters. These basic aspects of nucleation are not resolved in most of the measurement methods as the early stages of nucleation involve sub-nanometer clusters evolving very rapidly in time. Classical nucleation theories are usually based on simple models and properties of bulk materials, neglecting atomistic details. Atomistic simulations and numerical modelling, as employed in this work, can provide valuable insight into the nanoscale details of nucleation. In this thesis, our investigations are limited to homogeneous nucleation, and the studied systems vary from simple Lennard-Jonesium to fully atomistic models of complex molecular clusters. We have used various state-of-the-art equilibrium and non-equilibrium computational methods to shed light on the most important nucleation mechanisms in different conditions. Atomistic interactions were described by empirical force fields or quantum chemistry methods, as required by the system. The simulation results, reviewed in the context of both classical and non-classical nucleation theory, enabled us to uncover the nucleation pathways, cluster thermodynamics and structural (and energetic) evolution of the nucleating clusters. Based on the results presented in this thesis, molecular-level modelling is necessary to capture the microscopic effects related to the formation of the clusters. In addition, predicting nucleation rates of strongly bound atmospheric clusters requires non-classical treatment of both nucleation pathways and collision rates, as cluster-cluster collisions (not only monomer-cluster collisions) need to be accounted for, and the collision rate coefficients are affected by attractive long-range interactions. For loosely bound clusters, however, we have demonstrated that these phenomena can be ignored and thus the underlying framework of classical nucleation theory is working relatively well. We have further analysed the structural and energetic details of strongly undercooled clusters during the nucleation stage, and after equilibration.
  • Eskola, Ksenia (Helsingin yliopisto, 2021)
    This study examines the encounter between Finnish and Russian naming cultures (anthroponymy, naming systems and naming practices) in Finland and Russia from 2000 to 2018. It specifically focuses on the criteria for selecting names in Finnish–Russian families, name selections for native-speaking Russian children, official surname changes in Finland for Finnish and Russian name bearers and the use of Finnish given names in Russia. Socio-onomastics and name typology (structure) make up the theoretical and methodological framework of the study. In a broader context, the contact between the two languages is also part of the research. The materials comprise questionnaires and interviews involving criteria for name selection, documents on surname changes from the Names Committee of the Finnish Ministry of Justice, interviews and questionnaires on the use of Finnish given names in Russia and the given names of Russian children born in Finland. This doctoral study is composed of four articles as well as a summary which details the content of the articles and their findings. Articles I, II and III discuss given names and article IV covers surnames. Article I examines given names in bilingual Finnish–Russian families and discusses the criteria for selecting a name and the actual selections. It focuses on the main criteria for name selection in bilingual families: practicality and cultural ties. Article II continues with the investigation of given names, creating an overall picture of names given to native Russian-speaking children born in Finland. Article III covers Russia regionally and looks at the use and adaptation of Finnish given names in a Russian-language environment. The focus of article IV is on official surname changes made in Finland, changes in which the name bearer wishes to Fennicise a Russian surname and vice versa. I also discuss cases where an erroneous Finnish surname is corrected back to its original spelling in Russian. The summary provides a uniform overview of the study, along with its starting points, and pulls the findings of all the articles together. On a more general level, it considers what happens when Finnish and Russian naming cultures encounter one another in terms of naming systems as well as from the perspective of linguistic minorities. The study shows that along with the encounter between naming cultures, Finnish anthroponymy is becoming diverse in that Russian given names and surnames are entering its official nomenclature. In addition, Russian patronyms are being entered in the Finnish population register. These names, which are not found in the native Finnish-speaking population, are being counted as second or third given names as part of official Finnish nomenclature. Moreover, Russian unofficial names, those based on given names, an intrinsic part of Russian naming practice, can also be found in Finnish naming culture. As for Finnish given names, these are enriching the anthroponymy found in Russia, as Russian derivational suffixes are being used to form unofficial names under Russian naming practices.
  • Meriläinen, Pauliina (Helsingin yliopisto, 2020)
    Background: The purpose of this study is to bring understanding of what elements enable experts' knowledge sharing in digital service organizations. In digital service organizations the organizational structure is often project-based. Customer projects start and end throughout the calendar year, and the employees working within them may change along with the new projects. In addition, digital service companies have been actively hiring new employees. Rapidly grown number of new employees and the fact that the closest co-workers change throughout the year may cause challenges to the employees’ knowledge sharing within projects and beyond them to the wider organization. The elements which interrelation with employees’ knowledge sharing is examined in this study are self-determination theory’s three basic psycholog-ical needs, empowering leadership, and psychological safety. The theoretical framework is based on the concepts of knowledge and expertise, and on the previous research about the basic psychological needs and autonomous motivation, empowering leadership, and psychological safety at work. Problem: The aim of this research is to gain more understanding of what elements enable employees’ knowledge sharing in digital service organizations. The viewpoint is in the conditions where the employees operate at work. Methods: The nature of the research is qualitative interview study. The research material was collected by interviewing eight employees in one digital service company in spring 2020. Empirical data was analysed by theory- and data-driven content analysis. Results: The results of this study imply that the informants’ views on knowledge sharing at work were in line with the previous studies. All the elements examined interrelated with employees’ knowledge sharing as enabling it. Significance: The results bring understanding of what elements in organizations can enable employees’ motivation, ability, and opportunity to share their knowledge at work.
  • Eklund, Mia (Helsingin yliopisto, 2021)
    In this doctoral thesis I examine the prerequisites under which employers in Finland may process personal data of their employees (employee data) in connection with or as a part of various monitoring methods while, at the same time, taking into account the employees’ right to privacy. The purpose of this doctoral thesis is to illustrate the tensions that exist between, on the one hand, the Finnish legislation on employee privacy, which in Finland falls under the scope of labor law, and, one the other hand, i) other Finnish individual and collective labor law, ii) the EU’s general data protection regulation 2016/679 (“GDPR”) and iii) the compliance requirements applicable to employers (companies). This is done by examining and describing the applicable rules (and rules that should be applied) on employee privacy and on the processing of employee data in connection with monitoring of employees carried out by the employer (employee monitoring). This doctoral thesis consists of a summarizing part, which contains three chapters, and four previously published articles, one of which has been published in two separate parts. In the first chapter, I describe my research, including the research questions and the purpose of the research as well as my method. The first chapter also encompasses a brief description on all the articles forming part of the thesis. The second chapter contains a summary of all the articles and the conclusions which I have drawn based on the articles. The summary encompasses a presentation of both the themes and the purpose of the articles. In addition, the summary contains a review of the developments of relevant topics and legislation which I have covered in the articles and which relate mainly to the time after the publication of the articles. In the third chapter, I summarize my conclusions as a part of my concluding remarks. I also present certain reflections on topics which could be subject to future academic research. The main conclusions of my research for this doctoral thesis can be summarized as follows: i) The Finnish legislation on employee privacy appears non-compliant with the GDPR. The Finnish legislation, which under certain circumstances requires the employee’s consent, either as a basis for processing employee data or as an additional requirement for processing such data, to enable the employer to process employee data in connection with employee monitoring appears non-compliant with the rules of the GDPR and incompatible with the national room to maneuver provided for in the GDPR with regard to the processing of employee data. Also, the necessity requirement set forth in the Finnish Act on the Protection of Privacy in Working Life (759/2004) appears non-compliant with the GDPR. ii) There is an inherent tension between the Finnish legislation on employee privacy and the remainder of Finnish individual and collective labor law. More specifically, there is a conflict between the employers’ right to direct and supervise the work of its employees and the statutory requirements to obtain the employee’s consent in order for the employer to process employee data in connection with employee monitoring. On the one hand, the employer has a statutory right to direct and supervise the work carried out by its employees and, on the other hand, the processing of employee data in connection with certain types of monitoring require the employee’s consent. Employee monitoring, the purpose of which is to protect the employer’s property or to ensure compliance with applicable rules, usually concern the employees as a collective. From a systemic labor law perspective, matters that concern employees as a collective are, as a starting point, dealt with either as matters to be handled in cooperation negotiations in accordance with the cooperation legislation or in collective bargaining agreements. In this regard, requirements to obtain the individual employee’s consent constitute a clear and, from a practical perspective, problematic deviation from the labor law system, as a matter of collective nature is handled on an individual level. This deviation can partly be explained by the individual nature of the right to privacy as well as by the importance and meaning of the individual’s self-determination in the Finnish legal tradition. Also, the circumstances under which the legislation was enacted have had an impact. Agreeing on arrangements for control and monitoring measures, which affect all employees or groups of employees on a collective level, would from a labor law system perspective most naturally be handled in cooperation negotiations or in collective bargaining agreements. The Act on Co-operation within Undertakings as well as the Act on the Protection of Privacy in Working Life currently require that processing employee data in connection with, inter alia, employee monitoring shall be handled in cooperation negotiations. The GDPR’s form requirements for a valid consent and the information that is to be provided to the employee before obtaining his/her consent encompasses the same elements as the “agenda” of co-operation negotiations. Obtaining consent and arranging co-operation negotiations appear, at least partly, to fulfill the same purpose – ensuring transparency – and thus overlap. This should be taken into account in the ongoing revision of the Act on Co-operation within Undertakings. iii) There is a tension between the Finnish legislation on employee privacy and the increasing compliance requirements which companies are required and expected to take into account when doing business. In order to ensure compliance and prevent misconduct and to be able, if necessary, to investigate (potential) violations, employers (companies) are required to take active measures. In practice, compliance requires a structured and comprehensive system that covers, inter alia, appropriate monitoring mechanisms. However, consent as a processing basis or as an additional requirement for processing is problematic, as the employee may, by not giving his/her consent or by withdrawing his/her consent, prevent the employer from introducing or using monitoring mechanisms for purposes which may be deemed appropriate and necessary – both from the employer’s perspective as well as from the perspective of society more generally – to ensure compliance and prevent misconduct.
  • Eymann, Julia (Helsingin yliopisto, 2021)
    Vision is an important sensory modality for most vertebrates. The eye is a highly complex optical system at the center of which the neural retina acts as a sensory array. A stem cell population residing at the peripheral margin of the retina and Müller glia cells in the central retina mediate lifelong retinal growth and regeneration in fish and amphibians. The capacity for such retinal neurogenesis is reduced in birds and yet more limited in mammals. However, little is known about retinal development, postnatal growth and regeneration in squamate reptiles (lizards and snakes). Squamates occupy a central phylogenetic position among amniotes and display considerable morphological as well as functional diversity of the eye. This thesis explores various aspects of the squamate retina, particularly the neurogenic potential from embryonic development to postnatal growth and regeneration. First, the thesis elucidates the embryonic origins of the retinociliary junction (RCJ), a newly identified active stem/progenitor niche maintained in the postnatal retinal margin of squamates. The thesis then demonstrates a diverse spectrum of differing activity levels in the squamate RCJ. These variations in proliferative activity correlate with the diverse eye sizes, which is partly derived from differing ocular growth rates linked to RCJ activity. Next, although acute retinal damage does not stimulate a regenerative RCJ response, the thesis still highlights Müller glia cells as a potential source for regeneration in the squamate central retina. Finally, in the context of previously described vertebrate species, the thesis concludes that the squamate retina offers a new, more nuanced view on the field of vertebrate retinal growth and regeneration.

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