Väitöskirjat

Recent Submissions

  • Salo, Emma (Helsingin yliopisto, 2017)
    This thesis investigated brain activity with functional magnetic resonance imaging (fMRI) during selective and divided attention. Selective attention refers to the ability to selectively attend and process certain stimuli while ignoring others. Divided attention is needed, when two or more tasks requiring selective attention are performed in parallel. However, attention is easily caught by sudden changes in the environment. Brain activity and task performance during distracted and undistracted attention was also compared. The results showed that selective attention to auditory or visual modality enhanced activity in the auditory and visual cortices, respectively. However, the results also implied that the effects of selective attention may be influenced by task-irrelevant variation of the stimuli. The present thesis also showed that during divided attention, when two cognitively demanding tasks are performed in parallel, brain activity is enhanced in cortical areas in relation to the two tasks performed one at a time. Such activity enhancements specifically associated with divided attention were found in left middle frontal cortex during several different divided attention tasks. This suggests that division of attention requires specific, higher-level cognitive processes not needed in other attention-engaging tasks. However, not all dual tasks were associated with frontal activity enhancements. Complex selective attention tasks performed in parallel with another selective attention task may influence the higher-level cognitive processes or integration of two tasks needed during dual tasking.
  • Ren, Wei (Helsingin yliopisto, 2017)
    Nanowires (NWs) and nanotubes (NTs) are considered to be of great importance for future nanotechnology applications, due to the roles of dimensionality and small system size. Potential applications of NWs and NTs range from field-effect transistors to biological applications. However, the one-dimensional (1D) nanostructures and most of their applications are still in an early stage of technical development. There are several issues that need to be addressed before they are ripe for industrial applications. Irradiation has been widely used in semiconductor industry to modify the properties of materials since the 1950s. Irradiation in 1D nanomaterials has been studied to tailor the mechanical, electronic, optical and even magnetic properties in a controlled manner, to improve the functionality of the devices based on the 1D nanomaterials. This thesis focuses on the structural and mechanical modifications of the 1D nanomaterials under energetic ion irradiation, as well as the formation mechanisms of the composites of the functional one-dimensional nanomaterials to improve their usage. In the first part, we studied the defect production of GaN NWs under Ar irradiation. The difference of defect production between NWs and the bulk counterpart was studied. The effect of the large surface-area-to-volume ratio was found to play an importance role in defect production in NWs. The irradiation energy of the maximum damage production in the NWs has been obtained. In the second part of the thesis, we studied the formation of the composite nanomaterials of diamond-like-carbon (DLC) and carbon nanotubes (CNTs). We used the classical MD method to simulate the deposition process of carbon atoms on the CNT systems to provide the atomic insights into structural changes. The results show that high-sp$^3$-content DLC can be formed provided the deposition conditions allow for sidewards pressure to form from a substrate close beneath the CNTs.
  • Bukonte, Laura (Helsingin yliopisto, 2017)
    Defects always exists in a crystal lattice at temperatures above absolute zero. Our knowledge of defect concentration and mobility is crucial, due to their profound influence on the material properties. It has been shown that the presence of light impurities may enhance vacancy formation in many metals and metal alloys. The main reason for this phenomenon, often referred to as the superabundant vacancy formation, is the lowering of the vacancy formation energy due to the impurity trapping. In this thesis a theoretical thermodynamics model has been developed to study the equilibrium vacancy concentrations as a function of impurity concentration and temperature. The diffusion of monovacancies and hydrogen in tungsten is studied due to its relevance to fusion research. The molecular dynamics method has been used to simulate the diffusion of hydrogen and monovacancies in tungsten. The commonly accepted and so far used H diffusion migration barrier is revised and a new analysis method to determine diffusion coefficients that accounts for the random oscillation of atoms around the equilibrium position is presented. The results show the presence of multiple nearest neighbour jumps of monovacancy above 2/3 of the melting temperature of tungsten, that partly explains the upward curvature of Arrhenius diagram of self-diffusion experiments in tungsten. For the first time, the W monovacancy diffusion prefactor is calculated, and found to be unexpectedly high, resulting in a monovacancy diffusion attempt frequency of about 2-3 orders of magnitude higher than the values commonly used. A comparative study between the molecular dynamics and a Monte Carlo method – binary collision approximation has been carried out by simulating the single ion impacts on silicon and tungsten surfaces. The results from both methods are compared and found to be in a good agreement for crystalline structures. However, large discrepancies between the two methods arise for materials that are amorphous or become amorphized during ion irradiation.
  • Tenca, Andrea (Helsingin yliopisto, 2017)
    BACKGROUND AND AIM This thesis includes two studies conducted in a paediatric and two studies conducted in an adult primary sclerosing cholangitis (PSC) population. The common denominator was endoscopic retrograde cholangiography (ERC) with brush cytology that was performed in all patients. The aims were to: i) identify the possible environmental risk factors (Study I) and report the long-term outcome (Study II) of paediatric-onset PSC, ii) compare ERC and magnetic resonance imaging with cholangiopancreatography (MRI-MRCP) in the evaluation of disease activity and severity of patients with PSC (Study III) and evaluate the role of ERC with brush cytology as screening for cholangiocarcinoma (CC) in patients with PSC (Study IV). MATERIAL AND METHODS PSC was diagnosed, followed-up (or both) in Helsinki University Hospital (HUH). Study I: 71 patients with a new diagnosis of paediatric-onset (age < 16 years) PSC, autoimmune hepatitis (AIH) or PSC-AIH (togheter autoimmune liver diseases or AILD) between 1985-2011. Two control groups were used: 1) 91 IBD patients matched for gender and age, collected from the IBD Population Registry at HUH and 2) 716 healthy subjects matched for gender, age and also place of birth at the time of AILD diagnosis, collected from the Population Registry Centre. A questionnaire of 22 items was administered. Study II: 41 patients with a new diagnosis of paediatric-onset PSC between 1993-2011. Study III: 48 patients with PSC who underwent ERC and MRI-MRCP within + 3 months for the diagnosis or the follow-up of the disease. Study IV: 261 patients with a new diagnosis of PSC (age > 18 years) between 1 January 2006 and 31 October 2011. All cholangiographic images were scored according to the modified Amsterdam PSC score. RESULTS Study I: In multivariate analysis, children ‘living with a cat in a block of flats’ had a higher risk (OR 3.6; 95% CI: 1.2-10.8) of having AILD than healthy controls, but not IBD controls. Study II: At the end of follow-up (9 years, range 2-20 years) all children were alive and no malignancy occurred. 29/33 (88%) were not transplanted; 26/29 (78%) were not cirrhotic and 3/29 (10%) were cirrhotic. 4/33 (12%) were transplanted after a median of 7.5 years; no PSC recurrence in the graft occurred. Study III: MRCP and ERC scores for IHBD were associated with alkaline phosphatase (p = 0.016 and p = 0.018, respectively) and CA19-9 level (p < 0.001 and p = 0.030, respectively); MRCP score for EHBD was also associated with CA19-9 level (p = 0.021). Finally, peribiliary enhancement detected on MRI correlated with cytology findings for both IHBD (Spearman’s rho = 0.322, SE: 0.095, p = 0.022) and EHBD (Spearman’s rho = 0.319, SE: 0.113, p = 0.025, respectively). Study IV: Most of the patients were asymptomatic (211/261; 80.8%) and had only mild changes on cholangiography (149/261; 57.1%) at time of first ERC. Follow-up was completed in 249/261 (95%). CC developed in 7 patients and biliary dysplasia in 8 patients; brush cytology was suspicious or malignant in 8 patients at time of PSC diagnosis. Advanced EHBD cholangiographic changes (HR: 1.7; 95% CI: 1.2-2.3) and alanine aminotransferase (HR: 14.2; 95% CI: 1.9-106.4) were associated with increased risk of biliary neoplasia. CONCLUSIONS An unidentified environmental risk factor (i.e., microbial) especially associated with cats may increase the risk of PSC in children. The clinical course and outcome of paediatric-onset PSC seems to be good until adulthood with a high survival rate, with no occurrence of malignancy and LT required in only a minority of patients. MRI-MRCP use in PSC follow-up seems to be low. In this respect, ERC with brush cytology is a good screening tool for detection of biliary dysplasia or neoplasia (or both) in patients with PSC. Advanced extrahepatic disease and alanine aminotransferase elevation may predict the occurrence of CC.
  • Känsäkoski, Johanna (Helsingin yliopisto, 2017)
    Sexual differentiation and pubertal development are complex processes whose disruption leads to the abnormal development of primary and/or secondary sexual characteristics. Although mutations in several genes have been implicated in these disorders, the majority of the patients still lack a molecular genetic diagnosis. The aim of this thesis work was to identify genetic defects underlying complete androgen insensitivity syndrome (CAIS), congenital hypogonadotropic hypogonadism (CHH) and gonadotropin-dependent precocious puberty (GDPP), in Finnish and Danish patients. The genetic cause of CAIS was investigated in two siblings without identified mutations in the androgen receptor gene (AR). Whole-genome sequencing and AR cDNA analysis revealed a deep intronic mutation that led to abnormal splicing of AR mRNA and undetectable amount of AR protein in patient fibroblasts. The genetic causes of both extremes of pubertal variation, GDPP and CHH, were investigated in Danish patients. Twenty-nine Danish girls with GDPP were screened for mutations in MKRN3, which was recently identified as a regulator of pubertal onset, and one girl was found to have a mutation in this gene. Forty-one Danish CHH patients were screened for mutations in the CHH genes ANOS1, FGFR1, FGF8, PROK2, PROKR2, GNRHR, TAC3, TACR3, and KISS1R. Additionally, CHD7 was screened in two patients with hearing loss. Twelve patients were found to have a conclusive mutation; either in FGFR1 (5), ANOS1 (4), GNRHR (1), or CHD7 (2). SEMA3A and SEMA7A, two candidate genes of CHH, were screened in fifty Finnish CHH patients. Three SEMA3A variants and two SEMA7A variants were identified in the patients, but the identified variants do not seem to be sufficient to cause CHH alone. In conclusion, the intronic AR mutation is the first reported case of pseudoexon activation leading to CAIS demonstrating the importance of AR cDNA analysis in AIS patients without a molecular genetic diagnosis. Mutations in MKRN3 underlie GDPP in Denmark, although they are not very common in sporadic cases. FGFR1, ANOS1, GNRHR, and CHD7 mutations were found to underlie CHH in the Danish patients, but the majority still remain without a molecular genetic diagnosis. Finally, mutations in SEMA3A and SEMA7A do not seem to contribute significantly to CHH, and it remains to be seen whether mutations in these genes cause CHH in humans.
  • Mäkinen, Hanna (Helsingin yliopisto, 2017)
    Climate change is characterized by uncertainty in climate and increasing variability in weather. In addition to traditional ‘predict and adapt’ approaches of preparing for projected average long-term change in climate, approaches addressing adaptive capacity and system resilience are required. Diversity is associated with enhanced stability and resilience in the face of climate change. However, any kind of diversity does not necessarily enhance resilience, but the diversity of responses is critical to resilience. Such response diversity means that the ability to react to changes and variability differs within a functional group. In this thesis, response diversity was empirically assessed using forage crops, a response diversity index (RD-index) was constructed and the practical significance of the RD-index was demonstrated. Forage crops were chosen for the studies because they are a cornerstone of Finnish dairy and beef farming. The following species and their cultivars were included: timothy (Phleum pratense L.), meadow fescue (Festuca pratensis Huds.), tall fescue (Festuca arundinacea Schreb. syn. Lolium arundinaceum Schreb.), festulolium (Festulolium pabulare), Italian ryegrass (Lolium multiflorum L.) and red clover (Trifolium pratense L.). The analyses started with testing the effect of the hypothetically critical agro-climatic variables on forage crop yield performance using plant data from the Official Variety Trials of Natural Resources Institute Finland (126 cultivars) and the weather data of the Finnish Meteorological Institute from 1979 to 2012 that was matched to the phenology of the crops. A linear mixed model was used to determine the effect of the site, year and weather on crop yields (I, II). In the second round of analyses, the three-way interaction of cultivars, soil types and weather were analysed using mixed models (III). Within-species diversity of responses to individual weather variables was firstly investigated for the modern set of forage crop cultivars. The results revealed that in these, within-species diversity in response to weather was generally low, particularly within the modern set of timothy and meadow fescue cultivars. On the other hand, the set of modern festulolium cultivars showed higher levels of differences in responses, which indicates their greater capacity to cope with climate change (II). Principal component analysis was used to determine common weather patterns, and forage crops and their cultivars were clustered based on the scores of the principal component analysis (I, III). Response diversity to the critical weather patterns within the set of forage crop species and cultivars was found. The value of the RD-index, measured as numbers of identifiable functional groups of species and cultivars with similar yield responses, was 10 across the soil types. An increase in RD-index decreased the yield response variation. The practical significance of complementarity of yield 10 responses of forage crops and their cultivars represents an option for the enhancement of climate resilience of feed production. The RD-index of forage crops and their cultivars varied from one climate–soil type pattern to another, with the following RD-index values: coarse mineral soils = 4, clay = 9, organic soils = 8 (III). Due to the demonstrated dependency of crop responses to climate change on soil type, attention should be given to the plausible shifts in soil–climate combinations when planning adaptation.
  • Suomi, Irene (Helsingin yliopisto, 2017)
    Wind gusts, which are short duration (typically 3 s) wind speed maxima, are representative of the extreme wind conditions. They are very important for human activity, because the strongest gusts associated with storms are the most significant single cause of natural hazards. The impact of wind gusts on different structures depends on the characteristics of each structure. For example for wind energy, it is important to know both the probability of extreme maximum gusts in time scales of decades for the design of power plants and in the shorter term to support wind turbine operations. For wind gust forecasting it is essential to have reliable wind gust observations. Traditionally, observations have only been available from weather stations where the wind is usually measured at a reference height of 10 m. For wind energy, information is needed at greater heights, as the hub heights of the largest turbines extend even above 150 m. The main aim of this work has been to investigate wind gusts across the entire atmospheric boundary layer based on observations from tall meteorological masts as well as applying new measurement methods developed in this dissertation. The novel methods are based on turbulence measurements taken on board a research aircraft and by a Doppler lidar. The research aircraft can fly long distances in a short time, so the measured wind speeds do not represent wind speed variation in time but they are a function of flight distance. The new method developed in this dissertation to compare temporal and spatial scales allows the measurement of wind gusts from a research aircraft. Then, observations can be obtained from places where traditional weather stations or meteorological masts cannot be deployed. Applying the new method, the observed wind gusts from the marine Arctic matched well with those observed at a meteorological mast in the Baltic Sea, although also differences were observed between these environments. Doppler lidar provides radial wind speed measurements along a laser beam transmitted by the instrument. When data from at least three lines of sight are combined, the three-dimensional wind vector can be derived. However, the measurements from multiple lines of sight take several seconds, and the different beams represent different measurement volumes. For these reasons, the measured wind speed maxima from the Doppler lidar used in this work were higher than the corresponding wind gusts from the nearby meteorological mast. In this dissertation, we developed a new theoretical method that significantly reduced this positive bias. Wind gust measurements are usually prone to measurement errors, called outliers. The use of a spike removal algorithm typically applied in traditional turbulence measurements, resulted in significantly improved Doppler lidar data quality. The method performed even better than the traditional data quality assurance methods based on carrier-to-noise ratio, by removing the unrealistic outliers present in the time series. Based on the above wind gust measurements, it was found that in the lowest part of the atmospheric boundary layer the ratio of the wind gust speed and the mean wind speed, called the gust factor, decreases strongly with measurement height. The higher the aerodynamic roughness of the surface, the greater is the change. Moreover, the static stability of the atmosphere affects the gust factor: the decrease of the gust factor with height is clearly smaller in unstable than in stable conditions. The gust parameterizations used in numerical weather prediction models were originally designed for the reference measurement height of 10 m. A new parameterization was developed that takes into account not only the effects of surface roughness and atmospheric stability but also the height above the surface. Based on meteorological mast and research aircraft measurements, the new parametrization yielded better results than previous methods.
  • Ponto, Heli (Helsingin yliopisto, 2017)
    This study, positioned in the fields of humanistic geography and young people’s geographies, deals with young people’s place experiences in the city. I consider such experiences subjective, and study place from the perspective of personal relations and experienced insideness and outsideness. I also understand place as an intersubjective experience comprising social encounters. My research contributes to the literature on mobility, specifically in examining place from the perspective of daily mobility and personal networks. The participants were young people in upper-secondary education in the Helsinki metropolitan area, Finland. The research material consists of go-along interviews, photographs, GPS recordings and independent assignments, gathered in accordance with participatory methods. Earlier research findings indicate that adults define and restrict young people’s places in urban space, and that their experiences of insideness and outsideness are strongly elated to other meaningful social encounters. Daily mobility also tends to be perceived as a bodily and routine practice, whereas mobility opportunities are connected to young people’s experienced independence. According to the participants, socio-spatial tensions that typically arise between adults and young people no longer influenced the construction of their place experiences. The meanings of familiar childhood places, used for activities such as hanging out, changed as these young people were more commonly encountered as ‘almost adults’ in different places. Childhood places still evoked strong memories, but were no longer at the centre of daily life. They still had a significant bridge-building role in reconciling memories of familiar childhood places with contradictory experiences of new adulthood places. Thus, I claim that young people are experientially living between their childhood and adulthood places, actively constructing new personal places in their everyday environments in the process of growing up. The young people emphasised the importance of friends in fostering feelings of insideness with place. Groups of friends had their private ‘our’ places, but also more open places in which ‘they’ were welcome. Meetings with ‘them’ were easier if friends were present. Social encounters sometimes evoked strong feelings of outsideness despite the presence of friends, however, especially if such feelings were shared. Nevertheless, those who had the skills and resources to handle experiences related to encounters with different people in their daily places seemed to retain their feelings of insideness. My findings reveal that the construction of (inter)subjective meanings of places is tightly intertwined with daily mobility. The young people described how daily moving structured the experiential and bodily connections between them and their places, supporting their way of living and being in the city and enabling them to practise new adulthood. They had plenty of freedom related to daily, bodily mobility, and were restricted by a poor public-transport network, and the lack of a driving licence and vehicle, rather than parental strictures. Daily places form webs of meaningful places and experienced (dis)connections between places and people, in which (inter)subjective meaning-making is intermingled with daily mobilities. Given that experienced disconnections appear to arouse feelings of outsideness, young people should learn to recognize their experiential ties with places and handle the breakages. To do this they need places that support their everyday agency in terms of actively influencing their personal connections with places and promoting feelings of insideness. Keywords: young people, place experiences, place, everyday life, urban space
  • Sagalajev, Boriss (Helsingin yliopisto, 2017)
    Despite extensive research on the mechanisms of nociceptive pain, little is known about the processes that lead to neuropathic pain development. As one of the most severe and drug-resistant forms of chronic pain, neuropathic pain represents a major burden for patients, their families, and society. Therefore, new insights into the pathophysiology of neuropathic pain are needed. The amygdala represents a complex of brain nuclei responsible for mediating negative emotions, such as fear. Moreover, maladaptive changes in the amygdala contribute to the development of chronic pain and its comorbidities, such as anxiety and depression. However, little is known about the mechanisms for amygdala-mediated pain hypersensitivity in neuropathy. We therefore investigated descending pathways engaged by the amygdala for modulation of spinal nociception in neuropathic rats. In particular, we investigated the contribution of oxidative stress in the amygdala on the development of neuropathic pain. Oxidative stress is characterized by overproduction and poor detoxification of reactive oxygen species (ROS). ROS act as endogenous agonists of transient receptor potential (TRP) channels, which account for transduction of noxious stimulation to a nociceptive signal in peripheral nerves and for nociceptive transmission in the spinal cord. We therefore assessed how blocking TRP channels and detoxification of ROS with antioxidants in the amygdala influence pain hypersensitivity and pain affect in neuropathic rats. Furthermore, we investigated whether electrical cortical stimulation can reverse changes associated with pronociceptive activity of the amygdala. In particular, we examined descending pathways recruited by stimulation of the secondary somatosensory cortex (S2), which has proven to be an efficacious site for attenuation of drug-resistant neuropathic pain by transcranial magnetic stimulation (TMS) in patients. In the present series of studies, we demonstrate that N-methyl-D-aspartate (NMDA), TPRPA1, and TRPC4/5 channels in the amygdala contribute to the development of neuropathic pain and that amygdaloid treatment with antioxidants can attenuate this pain. Furthermore, we provide evidence that S2 stimulation suppresses spinal nociception in neuropathic animals with hypersensitivity, but not in animals without hypersensitivity or in control animals. Medullospinal serotonergic pathways acting on the spinal 5-HT1A receptor underlie the descending pain inhibition in neuropathic animals both following treatment of the amygdala with antioxidants or TRPA1 antagonists and following S2 cortex stimulation.
  • Gluschkoff, Kia (Helsingin yliopisto, 2017)
    Occupational stress in teaching concerns not only teachers; it also impacts on wider social contexts. It may negatively affect teachers’ health, but also indirectly influence students’ health and their academic achievements. Yet, despite the challenges teacher stress and health problems pose for society, little research has examined and compared the relevance of different psychosocial work characteristics in predicting poor teacher health, or explored mechanisms that explain or moderate these associations in the teaching profession. This thesis examined the associations between different psychosocial work characteristics and health-related outcomes among Finnish teachers, as well as the potential explanatory (i.e., mediating) and moderating mechanisms for these associations. The data were gathered via self-report questionnaires and included a cross-sectional sample of primary school teachers from the Helsinki metropolitan area of Finland and a longitudinal sample of teachers in primary or secondary education from the prospective Finnish Public Sector study. Psychosocial work characteristics involved job strain, effort-reward imbalance, organizational injustice, and teacher-targeted violence. The health-related outcomes potentially associated with psychosocial work characteristics included depressive symptoms, burnout, and sleep problems. In addition, the extent to which different aspects of recovery explained the associations and the moderating role of organizational justice were examined. Psychosocial work characteristics in terms of effort-reward imbalance and, to a lesser extent, with regard to job strain, were found to be relevant predictors of poor health in teaching. Effort-reward imbalance was associated with higher levels of burnout and, compared with job strain and organizational injustice, this was the most important predictor of depressive symptoms. Job strain was associated particularly with impaired sleep. Although organizational injustice did not seem to be a major predictor of poor health, high organizational justice represented a valuable resource in the teachers’ psychosocial work environment. Encountering violence at work had the most pronounced effect on sleep among teachers working in relatively unjust conditions, whereas the sleep of those perceiving high organizational justice was not affected by violence. Some of the effects of psychosocial work characteristics on health were mediated through aspects of recovery; namely, through sleep and recovery experiences during leisure time. Non-restorative sleep partially explained both the association of job strain with depressive symptoms and the association of effort-reward imbalance with depressive symptoms and overall burnout score. Furthermore, the association between effort-reward imbalance and burnout was partially mediated through poor relaxation during leisure time. The indirect effects were relatively weak, suggesting that although poor recovery may partly mediate the association between psychosocial work characteristics and health-related outcomes in teaching, it does not play a major role in the process. For teachers in basic education, reducing the demanding aspects of the psychosocial work environment and increasing the rewarding elements, such as the respect and support they receive, may be important in occupational stress prevention. Furthermore, although preventive measures against teacher-targeted violence should be prioritized, resources aimed at promoting organizational justice in schools may also mitigate the adverse consequences of teacher victimization. Although improving teachers’ psychosocial work environment is probably the most important means of supporting their health, interventions that help teachers unwind after working hours and reduce sleep problems may further complement workplace development programs.
  • Korhonen, Minna (Helsingin yliopisto, 2017)
    This dissertation is a mixed methods study of the alleged Americanisation of Australian English as it is perceived by the speakers and evinced in their language use. The study is based on sociolinguistic interview material collected in the small country town of Blayney in New South Wales, with participants from three age groups (adolescent, middle-aged and older speakers). Alongside speaker perceptions of the alleged American influence, this apparent time study investigates the variable pronunciations of a set of lexemes by the interview participants together with morphosyntactic features (subject-verb agreement with there-existentials and stative possessive have (got)) and discourse quotatives. The findings of the perceptual part of the study confirm that the speakers of all ages feel that Australian English is being influenced by American English. While the interview participants across generations confirm the existence of such influence, different language features are regarded as comprising Americanisms by different age groups. Thus, while the young speakers mainly see vocabulary as being Americanised, the older interviewees are more inclined to also include examples of spelling and pronunciation in their accounts. In terms of their actual language use, the investigation of the speakers’ pronunciation reveals that while some of the words are indeed increasingly pronounced in the perceived American style, others show hardly any variation across generations. The distributional analysis of the morphosyntactic features and discourse quotatives, on the other hand, shows generational patterning across all the variables. The findings provide support for the assumption that the younger speakers are more likely to use the more American style variants. Although these changes in the usage patterns cannot be attributed directly to American influence, the possibility of them being perceived as such by the speakers may strengthen their views of Americanisation. By taking into consideration both speakers’ perceptions and their language use the findings presented in this thesis offer significant insights into the alleged American English influence in the Australian English context.
  • Hakoköngäs, Eemeli (Helsingin yliopisto, 2017)
    Collective memory refers to a practice in which social conceptions about a common past are used to build and maintain togetherness and group identity in the present and for the future. Social representations of history describe the contents of collective memory. The present dissertation focuses on social representations of history and collective memory from the perspective of their visual forms. Visual images are important modes for communicating and creating conceptions of the past. Previous research has suggested that visual images have a strong mnemonic capacity due to their specific characteristics, including persuasion through realistic semblance, evoking emotions, creating a sense of identification, and their ability to tell narratives in a compact form. The dissertation consists of four original studies that examine visual collective memory. The material, Finnish history textbooks and advertisements, illustrates two different contexts of collective memory construction: institutional (textbooks) and informal (advertisements). Visual semiotics, as a methodological approach, is used to explain how the visual meaning system is constructed and maintained in social interactions. In this dissertation visual images are seen as giving social representations of history concrete and visible form and as activating culturally- and socially-bound meanings. The dissertation argues for the importance of analysing naturalized representations – social knowledge that has become taken for granted. The analysis of visual images of Finnish national history in textbooks shows that politics, war, and historic figures important to Finns – President Urho Kekkonen, Carl Gustaf Mannerheim and the mythical sorcerer Väinämöinen – are characteristic themes of Finnish visual collective memory. The images create a homogeneous picture of Finnishness as ethnic and religious minority groups are almost completely missing. Also, the country outside the urban areas is marginalized. The color blue, which objectifies the Finnish flag and anchors it to the idea of Finnishness, is the most widely shared element in the visualizations. Frequent yet subtle use of the color demonstrates the process of naturalization by which social knowledge acquires a firm position in the minds of group members. The analysis of Finnish advertisements shows how individual and group-level nostalgia intertwine whenever references to common conceptions invite an audience to reflect on their personal memories. The study suggests that it is possible to approach nostalgia as socially constructed and shared meaning that reflects present values, needs and desires. Advertisements construct everyday myths that serve the ideological function of representing the past as an object of desire. In the context of marketing, nostalgia is motivated by a shared concern that life today has lost some of the positive elements it once had. A combination of visual rhetoric and social representations theory help to demonstrate how commercials are used to affect not only consumer behaviour, but also broader everyday conceptions, such as the value of domestic production. In the campaigns analysed here, social representation anchored to the idea of tradition and emphasis on connections between generations serve to project a sense of continuity between the past, present and future. The results show how processes of anchoring, objectification and naturalization serve as tools of visual collective memory. The studies develop the use of visual semiotic analysis in social representations research for different types of visual material. Finally, the present dissertation suggests that analysing visual images complements our understanding of the characteristics of collective memory, and more generally, of the nature and processes of socially-constructed everyday knowledge.
  • Nieminen, Kati (Helsingin yliopisto, 2017)
    This dissertation consists of five previously published articles and an introduction, which introduces the theoretical framework, methodology, main arguments and the common themes of the articles. The overall contribution of the research is that it shows how, on one hand, the legal practices reproduce the unified citizen subject, and how the human subject is fragmented in legal practices on the other hand. In other words, this dissertation focuses in producing ‘us’ and ‘the other’ in law. The first two articles discuss the ways in which ‘us’, the citizen subject, is produced in law by observing how the European Court of Human Rights deflects disobedience and political protests. In the first article, Disobedient Subjects, I argue that in the so called headscarf cases, the logic of the legal argumentation can be traced back to the subjectivation of the citizen, as the Court reproduces the way in which the relationship between religion and the state is entangled with the citizen subjectivity. Moreover, my analysis shows that the Court’s approach to religion depends on whether religion is conceptualized as a personal belief system, cultural tradition, or as political. The second article, Rebels without a Cause? analyses the Court’s approach to disobedience. I argue that the political challenge the conscientious objector poses to their society is in legal proceedings transformed into a question of the personal right to freedom of religion and belief. Interestingly, the Court’s argumentation strategy is completely opposite regarding the Islamic headscarf cases on one hand, and conscientious objection to military service on the other hand. In the headscarf cases the Court chooses to emphasize the headscarf as a political symbol, whereas conscientious objection it treats as a manifestation of personal belief. These approaches could easily be reversed. In the third article, Who Belongs? I continue to discuss the construction of the modern Turkish citizen subjectivity. A Muslim woman wearing a headscarf, the conscientious objector, the Kurds struggling to be recognized as an ethnic minority, and the Gezi park protestors all pose the same question for the law, as they challenge the prevailing notion of possible identities and aspire to shift the limits of ‘us’ in order to include the excluded, or to question the dynamics of inclusion and exclusion more profoundly. In the third article my analysis shifts from the European Court of Human Rights to the ways in which the Turkish citizen subjectivity is challenged in the domestic courts, in the cabinets of power, and in the streets of Istanbul. The fourth and the fifth article move on to discuss othering in law. In The Detainee, the Prisoner, and the Refugee, I analyse the dynamics of subject production at the Guantanamo bay detention center, the maximum security prisons in the US, and the European refugee camps in order to explore the ways in which reduced legal subjectivities vulnerable to violence and exploitation, are produced and resisted in these sites, and how resistance, such as hunger striking, exposes the law’s violence. The fifth and final article, Forever Again, addresses the way in which responsibility for torture is deflected in two official documents, namely in the executive summary of the report on the CIA’s use of the so called enhanced interrogation techniques, and in CIA’s response to its claims. My analysis explains the discursive strategies that allow torture to be simultaneously absolutely prohibited and yet legally practiced. The themes of subjectivity, disobedience, and the law connect the five articles. In the introductory part I develop these themes further, and observe the fragmentation of the legal subject, the ways in which the theories of civil disobedience might contribute to totalizing the citizen subjectivity, and promote the idea of law as a discourse rather than a doctrine, institution, or system.
  • Holstila, Ansku (Helsingin yliopisto, 2017)
    Physical inactivity is a significant risk factor for non-communicable diseases. It has also been associated with a decline in functioning and a higher risk of work disability. However, there is limited evidence concerning the causes and consequences of changes in physical activity. Most Finnish adults of working age do not meet the recommendations for health-enhancing physical activity, and people tend to become less physically active as they age. Increasing activity levels among older age groups could enhance functioning and work ability among the ageing population. The aim of this thesis was, first, to examine how changes in physical activity are associated with subsequent health functioning, sickness absence and disability retirement. The physical and mental health functioning and sickness absence attributable to musculoskeletal and mental causes were examined separately. Second, the intention was to investigate how physical activity changes after the transition to statutory retirement and during post-retirement years. The research was part of the Helsinki Health Study being carried out at the Department of Public Health, University of Helsinki. The baseline surveys were conducted in 2000-2002 (N=8,960, response rate 67%) among employees of the City of Helsinki aged 40-60. The employees who responded to the baseline survey were followed up in two later surveys, meanwhile the cohort aged and some of the employees retired. The phase-2 follow-up survey was conducted in 2007 (N=7,332, response rate 83%) and phase 3 in 2012 (N=6,814, response rate 79%). The survey data were linked with register data on sickness absence from the Social Insurance Institution of Finland, and on disability retirement from the Finnish Centre for Pensions among those who consented to the register linkage (N=6,606). The register data on sickness absence and disability retirement includes medically confirmed diagnoses. Sickness absence periods were followed up from phase 2 until 2009, and disability retirement from phase 2 until 2013. Increased physical activity was associated with better physical health functioning and decreased activity with worse physical health functioning. There were fewer associations between changes in physical activity and mental health functioning. Increases in physical activity were associated with a lower risk of sickness absence. Vigorous physical activity was especially beneficial for physical health functioning and contributed to a lower risk of sickness absence attributable to musculoskeletal diseases. In contrast, a higher intensity of physical activity had less of an effect on mental functioning and sickness absence attributable to mental causes. In some cases, moderate-intensity physical activity was more beneficial to mental health functioning than higher-intensity activity. In addition, adopting vigorous physical activity was associated with a lower risk of disability retirement, and decreasing the intensity from vigorous to moderate or low was associated with a higher risk. Physical activity increased after the transition to statutory retirement, but declined a few years after retirement. Given the results of this study, ageing employees and retirees engaging in a low level of physical activity should be encouraged to increase the level. Vigorous activity could also be promoted, at least among healthy individuals. The transition to statutory retirement is a good opportunity to promote physical activity and thereby facilitate a change for the better. It is also important to support the maintenance of physical activity in the years following the transition to retirement.  
  • Benjamin, Saija (Helsingin yliopisto, 2017)
    This qualitative PhD study examines the lived experiences of eight young individuals who moved from one country to another several times during their childhood because of their parents’ profession, hence the term hypermobility in the title. As international, work-based mobility is increasing, it is of critical importance to observe how it affects childhood in general and how the children experience it in particular. The various socio-emotional aspects related to children’s hypermobility – often overlooked in discourses surrounding internationalization – are examined. This interdisciplinary study is situated in the field of intercultural education and guided by the following research question: How do children relocating with their families experience hypermobility? The data were gathered in Prague in 2013 with one-to-one semi-structured interviews that were conducted in English with eight youths (13 to 17 years old) who had moved internationally several times during their childhood and who had a “mixed” parental heritage. The interviews were complemented with self-chosen photographs and a life-grid. Interpretative Phenomenological Analysis (IPA, Smith, Flowers & Larkin 2009) was used as the methodological and analytical framework for the study. Four master themes emerged from the analysis as the predominant topics regarding the informants’ experiences of hypermobility. The themes disclose 1) the pervasive feelings of ephemerality and uncertainty outlining the youths’ everyday lives and relationships, 2) the different strategies the youths’ deploy to cope with the psychological strain related to the major life changes, 3) the ways the youths resort to multivoiced biographical narratives as a way to understand and describe the self, and 4) the feelings of connectedness that are grounded in self-created imageries, personal memories and (trans-generational) family narratives. In addition to the master themes, the role of international schools is discussed as significant in the youths’ identity and worldview development and as an environment where the youths’ complex life trajectories are normalized and validated. The rising calls for closed borders and nationalism necessitate increasing awareness of the diverse ways of being and belonging in societies and communities. Although based on a small sample of informants, this study opens a window for examining one way of inhabiting this world through the experiences of young mobile individuals. The findings enhance the current understanding of what it is like to grow up in the midst of international relocations in a world predominantly defined by sedentary norms and majority. The study’s conclusions should also prove to be particularly valuable to parents who consider or pursue an international career and for educators who work in schools with a high student turnover. Keywords: youth, third culture kids, international mobility, expatriates, international education