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  • Toroi, Paula (Helsingin yliopisto, 2009)
    The methods for estimating patient exposure in x-ray imaging are based on the measurement of radiation incident on the patient. In digital imaging, the useful dose range of the detector is large and excessive doses may remain undetected. Therefore, real-time monitoring of radiation exposure is important. According to international recommendations, the measurement uncertainty should be lower than 7% (confidence level 95%). The kerma-area product (KAP) is a measurement quantity used for monitoring patient exposure to radiation. A field KAP meter is typically attached to an x-ray device, and it is important to recognize the effect of this measurement geometry on the response of the meter. In a tandem calibration method, introduced in this study, a field KAP meter is used in its clinical position and calibration is performed with a reference KAP meter. This method provides a practical way to calibrate field KAP meters. However, the reference KAP meters require comprehensive calibration. In the calibration laboratory it is recommended to use standard radiation qualities. These qualities do not entirely correspond to the large range of clinical radiation qualities. In this work, the energy dependence of the response of different KAP meter types was examined. According to our findings, the recommended accuracy in KAP measurements is difficult to achieve with conventional KAP meters because of their strong energy dependence. The energy dependence of the response of a novel large KAP meter was found out to be much lower than with a conventional KAP meter. The accuracy of the tandem method can be improved by using this meter type as a reference meter. A KAP meter cannot be used to determine the radiation exposure of patients in mammography, in which part of the radiation beam is always aimed directly at the detector without attenuation produced by the tissue. This work assessed whether pixel values from this detector area could be used to monitor the radiation beam incident on the patient. The results were congruent with the tube output calculation, which is the method generally used for this purpose. The recommended accuracy can be achieved with the studied method. New optimization of radiation qualities and dose level is needed when other detector types are introduced. In this work, the optimal selections were examined with one direct digital detector type. For this device, the use of radiation qualities with higher energies was recommended and appropriate image quality was achieved by increasing the low dose level of the system.
  • Hiivala, Nora (Helsingin yliopisto, 2016)
    Until recently research on patient safety (PS) focused on secondary care, and little was known about the risks that patients face in primary care and especially in dental care. Only few studies have hitherto focused on the understanding of either the patients or their families about safety in dentistry. The objectives of this thesis were to identify types of dental patient safety incidents (PSIs), the contributory factors that played a role on the origin, development of PSIs, or identify the factors that increased the risk of PSIs, the mitigating factors against PSI, suggested by dentists and PS practices in use in their clinics. Furthermore, this thesis aimed at exploring whether patients or their families are able to observe PSIs in their own dental care. The study findings were derived from two datasets: 1) The first dataset was obtained from an internet-based questionnaire, sent in 2010 that requested practicing dentists to respond to questions on any PSIs that had occurred during the preceding year and any incident mitigating factors. A total of 1041 dentists responded (response rate 54%) and almost one third reported PSI(s) (n=872). 2) The second dataset was compiled from national data on patients or their family complaints and other notifications made against individual dental practitioners or dental practice units (n=948) for six Regional State Administrative Agencies (AVIs) and also from the National Supervisory Authority for Welfare and Health (Valvira) in Finland from 2000 to 2012 inclusive. The study used quantitative and qualitative research methods. Qualitative analyses (root cause analysis and document analysis) aimed to find emergent themes of dental PSIs and the factors related to them. The quantitative analyses examined several variables related to incident types, which included the contributing factors, the mitigating factors and their associations with dentists characteristics. The detected dental incident types in Finland are in many ways identical to reports from other countries. The two datasets provided somewhat different pictures of PSIs in dentistry. The dentists incident reports mostly captured incidents with relatively low severity, whereas patient complaints and supervisory data of healthcare regulators captured rarer but more serious events. This study showed that PS in dentistry is a complex and multidimensional issue and it relates to all aspects of care; diagnostics, treatment, devices and premises, medications, leadership and management, infection control, teamwork, communication, practitioner characteristics and patient characteristics. All dental PSIs in both datasets had a broad array of contributing factors including both human factors and latent system-factors. Compared to the total number of annual dental visits in Finland, severe dental PSIs are rare. However, less severe PSIs are more common, especially in prosthetics, dental surgery, endodontic and restorative treatments. According to dentist reports no significant difference existed in the incident rate between public and private dental practice. Yet two thirds (68%) of all studied patient complaints and other notifications concerned private professionals, whereas one third concerned public dental providers (32%). Most patients or family lodged complaints were lodged against individual dental professionals and only a minority was issued against dental practices or organizations. Nine out of ten complaints were made against dentists, the majority being general dental practitioners. Most (83%) dental professionals were complained about only once during the study period, however, a small number of dentists were responsible for a notable proportion of complaints from patients or received notifications concerning dentistry. These complaint-prone dentists carried a significantly higher risk for PSIs than did other dentists. The study also showed that patients and their families can be observant and are capable of identifying several incidents and hazardous circumstances in their dental care. Even serious safety risks that were otherwise probably not captured can be detected. The results show a relatively high prevalence of preventable incidents in Finnish dentistry. On the other hand, several mitigating factors had already implemented every day dental practice to safeguard patients in Finland. The problem is that the active use of novel methods varies between individuals and organizations. Patient protection in dentistry can be further enhanced by creating a more open PS culture. Such a culture should include improved incident reporting and should focus on learning from adverse events and also near misses. Anonymous, easy-to-use and blame-free reporting systems tailored for the specific features of dentistry might facilitate reporting. Development of proactive ways to intervene against complaint-prone dentists early and effectively to prevent an escalation of problems is also needed. PS issues should be implemented in undergraduate, post-graduate and continuing professional training. Further research should use different datasets, target groups (health care professionals, patients and their families), several PS research methods and include physical, emotional, social and economic consequences of dental incidents. Keywords: Patient safety, dentistry, incident type, degree of harm, prevention, patient complaints, malpractice
  • Vilo, Jaak (Helsingin yliopisto, 2002)
  • Junttila, Esa (Helsingin yliopisto, 2011)
    Reorganizing a dataset so that its hidden structure can be observed is useful in any data analysis task. For example, detecting a regularity in a dataset helps us to interpret the data, compress the data, and explain the processes behind the data. We study datasets that come in the form of binary matrices (tables with 0s and 1s). Our goal is to develop automatic methods that bring out certain patterns by permuting the rows and columns. We concentrate on the following patterns in binary matrices: consecutive-ones (C1P), simultaneous consecutive-ones (SC1P), nestedness, k-nestedness, and bandedness. These patterns reflect specific types of interplay and variation between the rows and columns, such as continuity and hierarchies. Furthermore, their combinatorial properties are interlinked, which helps us to develop the theory of binary matrices and efficient algorithms. Indeed, we can detect all these patterns in a binary matrix efficiently, that is, in polynomial time in the size of the matrix. Since real-world datasets often contain noise and errors, we rarely witness perfect patterns. Therefore we also need to assess how far an input matrix is from a pattern: we count the number of flips (from 0s to 1s or vice versa) needed to bring out the perfect pattern in the matrix. Unfortunately, for most patterns it is an NP-complete problem to find the minimum distance to a matrix that has the perfect pattern, which means that the existence of a polynomial-time algorithm is unlikely. To find patterns in datasets with noise, we need methods that are noise-tolerant and work in practical time with large datasets. The theory of binary matrices gives rise to robust heuristics that have good performance with synthetic data and discover easily interpretable structures in real-world datasets: dialectical variation in the spoken Finnish language, division of European locations by the hierarchies found in mammal occurrences, and co-occuring groups in network data. In addition to determining the distance from a dataset to a pattern, we need to determine whether the pattern is significant or a mere occurrence of a random chance. To this end, we use significance testing: we deem a dataset significant if it appears exceptional when compared to datasets generated from a certain null hypothesis. After detecting a significant pattern in a dataset, it is up to domain experts to interpret the results in the terms of the application.
  • Ruutu, Hanna (Helsingin yliopisto, 2007)
    This study examines the position and meaning of Classical mythological plots, themes and characters in the oeuvre of the Russian Modernist poet Marina Tsvetaeva (1892-1941). The material consists of lyric poems from the collection Posle Rossii (1928) and two longer lyrical tragedies, Ariadna (1924) and Fedra (1927). These works are examined in the context of Russian Modernism and Tsvetaeva s own poetic development, also taking into account the author s biography, namely, her correspondence with Boris Pasternak. Tsvetaeva s appropriations of the myths enter into a dialogue with the Classical tradition and with the earlier Russian and Western literary manifestations of the source material. Her Classical texts are inextricably linked with her own authorial myth, they are used to project both her ideas about poetry as well as the authored self of her poems. An important context for Tsvetaeva s application of the Classical myths is the concept of the Platonic ladder of Eros. This plot evokes the process of transcendence of the mortal subject into the immaterial realm and is applied by the author as an extended metaphor of the poet s birth. Emphasizing the dialectical movement between the earthly and the divine, Tsvetaeva s Classical personae foreground various positions of the individual between these two realms. By means of kaleidoscopic reformulations of similar metaphors and concepts, Tsvetaeva s mythological poems illustrate the poet s position between the material and the immaterial and the various consequences of this dichotomy on the creative mission. At the heart of Tsvetaeva s appropriation of the Sibyl, Phaedra, Eurydice and Ariadne is the tension between the body and disembodiment. The two lyrical tragedies develop the dichotomous worldview further, nevertheless emphasizing the dual perspective of the divine and the earthly realms: immaterial existence is often evaluated from a material perspective and vice versa. The Platonic subtext is central for Ariadna, focussing on Theseus development from an earthly hero to a spiritual one. Fedra concentrates on Phaedra s divinely induced physical passion, which is nevertheless evoked in a creative light.
  • Kysenius, Kai (Helsingin yliopisto, 2015)
    Aging-related increase of neuronal stress may promote the development of sporadic late-onset Alzheimer s disease (LOAD) and other forms of dementia. LOAD risk is also increased by genetic factors such as ApoE4 and diseases such as type 2 diabetes (T2D). Early LOAD pathology is characterized by alterations in brain lipoprotein receptor expression and neuronal hypometabolism. Multifunctional lipoprotein receptors regulate neuronal plasticity, cholesterol and metabolic homeostasis. Lipoprotein receptors apolipoprotein receptor 2 (ApoER2) and very-low density lipoprotein receptor (VLDLR) bind ApoE, but also interact with proteins centrally involved in LOAD pathogenesis. Proprotein convertase subtilisin/kexin type 9 (PCSK9) and the nutraceutical berberine modulate lipoprotein receptor levels in vivo. PCSK9 inhibitors and berberine have recently surfaced as promising treatment options for hypercholesterolemia and T2D, respectively. Additionally, PCSK9 and berberine are implicated in pathways modulating neuronal viability, suggesting they may hold therapeutic potential against neurodegenerative diseases. However, the effects of PCSK9 and berberine on neuronal cell death and lipoprotein receptors are currently poorly understood. The objective of this study was to elucidate the role of PCSK9 and berberine as modulators of lipoprotein receptors and cell death in neurons. The effects of RNAi-mediated PCSK9 downregulation and berberine on neuronal viability were studied in mouse and rat primary neuron cultures. Mechanistic basis of effects were further studied in combination with lentiviral RNA interference, kinase inhibitors and various inducers of cellular stress and cell death. Cell viabilities were assessed by immunofluorescence, Western blotting, and cell toxicity and mitochondrial assays. The main conclusions of this study are: (1) reducing endogenous PCSK9 levels genetically by lentiviral-mediated RNAi protects neurons against apoptotic cell death in an ApoER2-dependent fashion; (2) a potential PCSK9 inhibitor and a widely used nutraceutical berberine causes mitochondria- and NMDA receptor-dependent neuronal cell death at micromolar concentrations; (3) at subtoxic nanomolar concentrations, berberine sensitizes neurons to rotenone and glutamate toxicity calling for caution in berberine dosing and chronic use; and (4) subtoxic stress, including berberine, increase neuronal VLDLR expression, associated with a biphasic effect on the stabilization of the transcription factors hypoxia-inducible factor 1α and β-catenin. To conclude, ApoER2, VLDLR and their modulators PCSK9 and berberine contribute to the regulation of neuronal cell death via multiple mechanisms, suggesting a potential role in neurodegenerative disease pathogenesis at the interface of metabolism and survival signaling.
  • Uutela, Marko (Helsingin yliopisto, 2004)
  • Sahlstedt, Heli (Helsingin yliopisto, 2015)
    The aim of this study is to introduce how basic education works in Finland with the new comprehensive school form, in which all pupils from grades 1 9 study in the same school building. The school is specially designed and constructed for this purpose. The view point of this research is school pedagogy. This study describes the development of normal institutional school guidance towards the newest school form with a focus on the vertical and coherence development in the Finnish school system. The study examines experiences of unified comprehensive school practice from the view point of teachers, pupils and guardians. It investigates the diverse diversity of opinions between teachers, pupils and guardians and what things should be considered in the future when new schools like this are built. The research involved a case study of a new unified comprehensive school built in a capital region of Finland in 2006. The research data were collected in five different phases between 2005 and 2010. The data consist of answers from 275 guardians, 871 pupils and 64 teachers. The study used mixed methods, and the data were collected with Quest-MM according to closed and open questions. The qualitative data were analysed with the content analysis. The quantitative material was analysed by using the Kruskall-Wallis test and cross tables. According to the results, the teachers, pupils and guardians showed significant statistical differences in their opinions about the school. Altogether 83 % of the guardians and 71 % of pupils were satisfied with the unified comprehensive school. In fact, 70 % of the guardians and 60 % of the pupils wanted to see the construction of more unified comprehensive schools. The guardians focused on the safety of their own child in the school. They appreciated that in the new school form, their child did not have to change schools between grades 6 and 7, a transition that the parents usually found to be undesirable. The students tended to highlight the informal elements, such as friendship, the school environment and school rules; they also showed marked age-related differences in their views. The teens thought that the unified comprehensive school was suited mainly for the younger primary school pupils. The teachers were the most critical of the new school form; 53 % of them were satisfied with it, and only 29 % wanted to see more of them. The teachers considered the matter primarily from the point of view of their own work. They thought the unified comprehensive school was a rich working environment, but disliked it as an organization. According to the teachers, the unified comprehensive schools are built too large to function effectively. The action of a large school organization must be divided, so that the risk of the parts is to divide such action too much. Horizontal coherence did not work. Also, the guardians, like the teachers were skeptical of the number of pupils in the unified comprehensive school. According the guardians, large size of the school units reduced the safety of the pupils. The result show that one can see the need to reduce the size of the unified comprehensive school for the benefit of the pupils and teachers. Additionally, school ergonomics, school culture and pedagogy also deserve careful consideration. The school must to realise that pupils studying between the ages of 6 and 16 have different needs. The unified comprehensive school seems to require more resources or help from outside of the school in establishing their pedagogy and school culture from the beginning. ________________________________________ Keywords: basic education, comprehensive school, unified comprehensive school, school pedagogy
  • Koroknay-Pál, Päivi (Helsingin yliopisto, 2012)
    Objectives. Intracranial aneurysms in children are rare and population-based long-term follow-up studies are limited. In this study, a large clinical and angiographic long-term follow-up was carried out. The special characteristics of the patients and their aneurysms were assessed together with factors affecting early and long-term morbidity and mortality. Materials and Methods. All pediatric (≤18 years) aneurysm patients treated at the Department of Neurosurgery in Helsinki during 1937-2009 were followed from diagnosis until death or the end of the year 2011. Later patient data were gathered from the referring hospitals, and a new follow-up was organized. The long-term excess mortality was calculated by using relative survival ratio. Results. Patients comprised 114 individuals with 130 aneurysms. Most aneurysms were ruptured and of medium size. Internal carotid artery bifurcation was the most common location, and boys were predominantly affected. The majority of the aneurysms were treated surgically. After a mean follow-up time of 25 years, 62% of the patients had a good outcome, 3% were dependent and 35% had died. Of the survivors, 91% lived independently at home and were meaningfully employed. Twenty-eight percent of the survivors were high school graduates. Factors correlating with a favorable long-term outcome were aneurysm location in the anterior circulation, operative treatment, and complete aneurysm closure postoperatively. Fourteen patients (12%) had a family history of aneurysms. Fifty-nine patients had long-term angiographic follow-up data (median follow-up 34 yrs). Of these patients, 41% were diagnosed with a total of 36 new aneurysms. Seven new subarachnoid hemorrhages (SAH) occurred. The annual rate of development of new aneurysm was 1.9% and that of hemorrhage 0.4%. Current or previous smoking (odds ratio 3.39, 95% confidence interval [CI] 1.02-11.29, p=0.047) was the only significant risk factor for new aneurysm formation. No independent risk factors for new SAH emerged. Cumulative risk of new SAH 40 years after the initial diagnosis was 15% (95% CI 5-25%). There was an overall excess mortality of 10% and 19% at 20 and 40 years after the diagnosis among the one-year survivors, respectively. The excess mortality was particularly high in male patients, and was mainly aneurysm-related. Conclusions. Most patients had a good recovery, but almost half of them developed new aneurysms during a follow-up of 34 years, with smoking being a major risk factor. A long-term excess mortality exists in pediatric aneurysm patients, especially males, even decades after successful treatment of a ruptured aneurysm. The excess mortality is mainly aneurysm-related. A life-long angiographic follow-up is mandatory in these patients.
  • Sipilä, Raija (Helsingin yliopisto, 2012)
    Clinical practices are not sufficiently in line with current evidence compiled in evidence based guidelines. Changing practice behaviour is challenging. Therefore active, tailored and often local interventions are needed to lead these changes. ---- The aims of the present study were to describe a local, practical and comprehensive multifaceted guideline implementation intervention, assess the feasibility of the intervention and its effects on care processes. The second aim was to approximate the time resources needed for preventive activities. The third aim was at patient level to evaluate long-term effects of an individualised lifestyle intervention on cardiovascular risk factor levels. ---- The key components of the two-year intervention were internal pair facilitation, education and consensus meetings, local guideline development, audit and feedback, and marketing. The feasibility of the intervention, and structure and process changes were measured with questionnaires and clinical audit recordings during appointments (BP measurements, diabetes and dyslipidaemia patients). National Prescription register data was used to evaluate changes in antihypertensive drug prescribing and chart audits to assess long-term clinical outcomes. ---- For different patient groups changes in the division of tasks had been made at 22 29 of 31 practices, different local guidelines were adopted at 22 31 practices and self-measurement sites were set up for all practices. BP measurements were reduced and targeted at those with poor treatment balance. Using modelling the time allocations by nurses for BP measurements and lifestyle counselling were reduced from 11.9% to 6.3% of their total working time. No statistical changes between intervention and control GPs were detected in time in antihypertensive prescribing. The main advantages of the intervention were mutual clinical practices and clarified professional roles. The main barrier to change was time constrains. ---- In conclusion, internal facilitation is a feasible way of promoting changes in care processes in primary care. However, support and leadership are needed to adopt systematic and sustained quality improvement (QI). Multiprofessionality is important in QI initiatives in primary care, but some practices, such as prescribing, need more individualised interventions.
  • Eränpalo, Tommi (Helsingin yliopisto, 2015)
    Abstract This dissertation deals with young people s civic skills and how these competences can be developed particularly in civics education at school by means of gamification. The dissertation consists of four sub-studies written in article form as well as a summary. The articles examine young people s civic behaviour from the perspective of conceptions of democracy, civic competence and civic identity. The current generation of youth and young adults seems to be shunning the traditional structures of civic participation and political decision making. Young people are re-evaluating their own roles in civic discussion and are often choosing methods that are outside the official channels. To further develop civic activism, this state of affairs should be changed, since our future decision makers will ultimately emerge from this group of people. The role of the school is seen as essential in scientific debate on the subject. The dissertation commences with the question of how deceptive the suggestion is that young people are passive, and how civic education didactics need new ways to recognise students involvement in civic matters. This query is addressed by means of finding new methods for civics education, using, for example, gamification and dialogue education. The intention of the dissertation is to answer the following questions: a) What aspects of young people s civic skills can be detected in the deliberation resulting from game playing? b) How should civics education at school be developed to strengthen young people s inclusion in civic affairs? The Grounded theory method is applied in the study. Each dissertation article introduces a new perspective on the research phenomenon, and the analysis of the research material proceeds in stages revealing new information on young people s civic competence. The theoretical conclusions of the study are presented in the summary. The first article focuses on the public image of young people s civic competence, which has been marked by pessimism in the early 21st century. This negative image has been publicly debated in conjunction with international surveys indicating young people s passive behaviour in civic orientation (CIVED 1999 and ICCS 2009). The article looks for a new perspective by ques-tioning the pessimistic interpretations of these surveys. It also presents new research evidence of a more active youth culture. The second and third articles venture deeper into the world of young people s civic competence. The image of young people being passive is often maintained by the conventional discussion culture in schools, one that avoids open ideological and political debate and does not particularly encourage deliberation on civic matters. The articles raise issues concerning the atmosphere in the classroom as well as the role of the student in education and society as a whole. It also presents the Act now! game, developed by the author and the author s students. The game aims to provide a framework for dealing with civic issues by means of deliberation. The fourth article introduces the concept of dialogue in education, and a comparative Scandinavian example of it. The Act now! game was played in Finland, Sweden and Norway. The article focuses on dialogue education as part of young people s civics education, and examines the features that emerge from analysing civic identity among Scandinavian youth. The summary presents the results in a way that is typical to the Grounded theory method. It then provides a summarizing analysis of them. The results justify claiming that teaching methods involving deliberation in civic education stimulate and strengthen young people s participatory civic orientation as well as their civic competence. The summary also speculates on the possibilities of increasing young people s motivation to participate in civic issues. The competences that arise from young people s deliberation indicate how the young are capable of responding to civic responsibility. The results also high-light the democratic-political need to create a forum in which young people may engage in civic deliberation. The ongoing curricular reform in Finnish primary and secondary schools will emphasise student involvement as well as creating a new and more active role for students. Accordingly, the results of this study can be implemented in civics teaching. They also suggest that deliberation instruments such as the Act Now! game could be used as a solution to didactic needs on a wider scale. A game-like method offers an example of dialogical teaching that enables a path to deliberation. Keywords: Civic competence, deliberation, gamification, inclusion
  • Leinikki, Sikke (Helsingin yliopisto, 2009)
    This study analyzes the forming of the occupational identity of the well-educated fixed-term employees. Fixed-term employment contracts amongst the well-educated labour force are exceptionally common in Finland as compared to other European countries. Two groups of modern fixed-term employees are distinguished. The first comprises well-educated women employed in the public sector whose fixed-term employment often consists of successive periods as temporary substitutes. The other group comprises well-educated, upper white-collar men aged over 40, whose fixed-term employment careers often consist of jobs of project nature or posts that are filled for a fixed period only. Method of the study For the empirical data I interviewed 35 persons (26 women and 9 men) in 33 interviews, one of which was conducted by e-mail and one was a group interview. All the interviews were electronically recorded and coded. All the interviewees have two things in common: fixed-term employment and formal high education. Thirteen (13) of them are researchers, four nurses, four midwives, four journalists, and ten project experts. I used the snowball method to get in touch the interviewees. The first interviewees were those who were recommended by the trade unions and by my personal acquaintances. These interviewees, in turn, recommended other potential interviewees. In addition, announcements on the internet pages of the trade unions were used to reach other interviewees. In analysing process I read the research material several times to find the turning points in the narrative the interviewees told. I also searched for the most meaningful stories told and the meaning the interviewees gave to these stories and to the whole narrative. In addition to that I paid attention to co-production of the narrative with the interviewees and analyzed the narrative as performance to be able to search for the preferred identities the interviewees perform. (Riesman 2001, 698-701). I do not pay much attention to the question of truth of a narrative in the sense of its correspondence with facts; rather I think a working life narrative has two tasks: On the one hand one has to tell the facts and on the other hand, he/she has to describe the meaning of these facts to herself/himself. To emphasize the double nature of the narrative about one’s working life I analyzed the empirical data both by categorizing it according to the cultural models of storytelling (heroic story, comedy, irony and tragedy) and by studying the themes most of the interviewees talked about. Ethics of the study I chose to use narrative within qualitative interviews on the grounds that in my opinion is more ethical and more empowering than the more traditional structured interview methods. During the research process I carefully followed the ethical rules of a qualitative research. The purpose of the interviews and the research was told to the interviewees by giving them a written description of the study. Oral permission to use the interview in this research was obtained from the interviewees. The names and places, which are mentioned in the study, are changed to conceal the actual identity of the interviewees. I shared the analysis with the interviewees by sending each of them the first analysis of their personal interview. This way I asked them to make sure that the identity was hidden well enough and hoped to give interviewees a chance to look at their narratives, to instigate new actions and sustain the present one (Smith 2001, 721). Also I hoped to enjoy a new possibility of joint authorship. Main results As a result of the study I introduce six models of telling a story. The four typical western cultural models that guide the telling are: heroic story, comedy, tragedy and satirical story (Hänninen 1999). In addition to these models I found two ways of telling a career filled with fixed-term employments that differ significantly from traditional career story telling. However, the story models in which the interviewees pour their experience locates the fixed term employers work career in an imagined life trajectory and reveals the meaning they give to it. I analyze the many sided heroic story that Liisa tells as an example of the strength of the fear of failing or losing the job the fixed term employee feels. By this structure it is also possible to show that success is felt to be entirely a matter of chance. Tragedy, the failure in one’s trial to get something, is a model I introduce with the help of Vilppu’s story. This narrative gets its meaning both from the sorrow of the failure in the past and the rise of something new the teller has found. Aino tells her story as a comedy. By introducing her narrative, I suggest that the purpose of the comedy, a stronger social consensus, gets deeper and darker shade by fixed-term employment: one who works as a fixed term employee has to take his/her place in his/her work community by him/herself without the support the community gives to those in permanent position. By studying the satiric model Rauno uses, I argue that using irony both turns the power structures to a carnival and builds free space to the teller of the story and to the listener. Irony also helps in building a consensus, mutual understanding, between the teller and the listener and it shows the distance the teller tells to exist between him and others. Irony, however, demands some kind of success in one’s occupational career but also at least a minor disappointment in the progress of it. Helmi tells her story merely as a detective story. By introducing Helmi’s narrative, I argue that this story model strengthens the trust in fairness of the society the teller and the listener share. The analysis also emphasizes the central position of identity work, which is caused by fixed-term employment. Most of the interviewees talked about getting along in working life. I introduced Sari’s narrative as an example of this. In both of these latter narratives one’s personal character and habits are lifted as permanent parts of the actual professional expertise, which in turn varies according to different situations. By introducing these models, I reveal that the fixed-term employees have different strategies to cope with their job situations and these strategies vary according to their personal motives and situations and the actual purpose of the interview. However, I argue that they feel the space between their hopes and fears narrow and unsecure. In the research report I also introduce pieces of the stories – themes – that the interviewees use to build these survival strategies. They use their personal curriculum vitae or portfolio, their position in work community and their work morals to build their professional identity. Professional identity is flexible and varies in time and place, but even then it offers a tool to fix one’s identity work into something. It offers a viewpoint to society and a tool to measure one’s position in surrounding social nets. As one result of the study I analyze the position the fixed-term employees share on the edge of their job communities. I summarize the hopes and fears the interviewees have concerning employers, trade unions, educational institutions and the whole society. In their opinion, the solidarity between people has been weakened by the short-sighted power of the economy. The impact the fixed-term employment has on one’s professional identity and social capital is a many-sided and versatile process. Fixed-term employment both strengthens and weakens the professional identity, social capital and the building of trust. Fixed-term employment also affects one’s day-to-day life by excluding her/him from the norm and by one’s difficulty in making long-term plans (Jokinen 2005). Regardless of the nature of the job contract, the workers themselves are experts in making the best of their sometimes less than satisfying work life and they also build their professional identity by using creatively their education, work experiences and interpersonal relations. However, a long career of short fixed-term employments may seriously change the perception of employee about his/her role. He/she may start concentrating only in coping in his/her unsatisfactory situation and leaves the active improvement of the lousy working conditions to other people. Keywords: narrative, fixed-tem employment, occupational identity, work, story model, social capital, career  
  • Mikkola, Hannu (Helsingin yliopisto, 2012)
    Energy potential, energy ratios, and the amount of net energy in Finnish field crop production were studied in this thesis. Special attention was paid to indirect energy inputs and how to treat them in energy analysis. Manufacturing of machines and agrochemicals and production of seeds are examples of indirect energy inputs. The bioenergy potential of the Finnish field crop production could be as large as 12 – 22 TWh, or 3 – 5% of the total energy consumption in Finland in 2008. The major part of this energy would originate from straw and biomass like reed canary grass cultivated for energy use. However, only 0.5 TWh of the potential is utilized. The output/input energy ratios of the studied field crops varied from 3 to 18, being highest (18) for reed canary grass and second highest (7) for sugar beet and grass cultivated for silage. The energy ratio of cereals and oil seed crops varied from 3 to 5 if only the yield of seeds was considered. If the yield of straw and stems was also taken into account the energy ratios would have been almost twofold. The energy ratios for Finnish wheat and barley were as high as those gained in Italian and Spanish conditions, respectively. However, the energy ratios of maize, elephant grass and giant reed were even over 50 in Central and Southern Europe. Plants that use the C4 photosynthesis pathway and produce high biomass yields thrive best in warm and sunny climate conditions. They use nitrogen and water more sparingly than C3 plants typically thriving in the cooler part of the temperate zone. When evaluating energy ratios for field crops it should be kept in mind that the maximal energy potential of the energy crop is the heating value of the dry matter at the field gate. Transportation of the crop and production of liquid fuels and electricity from biomass lowers the energy ratio. A comparison of field energy crops to a reforested field suggested that fast growing trees, as hybrid aspen and silver birch, would yield almost as high energy ratio (47 – 53) as obtained from the C4 plants cultivated in warmer regions. The net energy yield of trees would also be competitive with those of the Finnish field energy crops (51 – 85 GJ ha-1). Energy analysis methods for field crops should be unified in order to ease comparison of results. Analyses of energy inputs could be improved by establishing an open, international data base that would contain results from only transparent and well-documented studies. Such a data base would standardize analysis methods but it would also speed up analysing, improve the quality of the results and ease the interpretation.
  • Wrede-Jäntti, Matilda (Helsingin yliopisto, 2010)
    Your money or your life? A qualitative follow-up study of the young unemployed from an actor perspective is a qualitative and longitudinal study following 36 unemployed young people in Helsinki over a span of ten years. The purpose of the study is to shed light on how a few young people view employment/unemployment and their lives and future, how they as unemployed perceive their encounters with society, and how society supports them. Four so-called key informants were followed at a finer level of empirical detail. They were chosen for the thematic interviews because of their different personalities, starting points and preferences. Although some differences were expected, what the results show is quite striking. The individual stories raise a number of questions about differences between young people, about society s view of the young unemployed, and about the principles behind the so-called activation policy and how society s support is distributed. The key informants descriptions underline that the group young unemployed does not consist of individuals who are alike but that life is complex, that paid work and unemployment can be perceived very differently, and that background and unofficial support can have consequences for self-perception and for ways of looking at the future, vocational choices, paid work and activation policy. Margaret S. Archer s theory of Morphogenesis and Barbara Cruikshank s theory of constructing democracies compose the study s theoretical framework. The key informants stories give a picture of a formal support system that, even though it puts part of the responsibility for unemployment on the individuals themselves, in the name of fairness and equality, treats them in an impersonal way, not giving their personal situation and wishes much weight. As a consequence, those who share the dominant values of society do well, while others who do not are faced with difficulties. The bigger the gap between society s and the individual s values, the bigger the risk to be met by little understanding and by penalties. And vice versa: Those who initially have the right values and know how to deal with authorities get heard and their opinions get accepted. The informants ask for a more personal encounter, which could improve both the atmosphere and the clients experiences of being heard. Still the risk of having a more individualistic system should be addressed, as a new system might generate new winners, but just as well give new losers. Finally, we have to ask if the so-called activation policy is looking for answers primarily to a macro-level problem on the micro-level. If it does not produce more jobs, its support for the unemployed will be insignificant. It is not enough to think about what to do at the grassroots level to make the system more functional and support job-seeking. If the current rate of unemployment endures, the quality of life of the unemployed should be addressed. A first step could be taken by placing less guilt on the unemployed. Instead of talking about activating the unemployed, discussion should be targeted at removing structural impediments to employment. If we want to have less polarisation between the those with paid work and those without, who often struggle with low incomes, we need to include the macro-level in the discussion. What does high unemployment mean in a work-based society, where the individual s self-perception and important social forms of support are linked to labour income? And what can be done at the macro-level to change this undesirable condition at the micro-level? Keywords: Unemployment, Youth, Public interventions, Activation policy, Individual actors, Qualitative, Longitudinal, Holistic, Helsinki, Finland
  • Povelainen, Mira (Helsingin yliopisto, 2008)
    The ultimate goal of this study has been to construct metabolically engineered microbial strains capable of fermenting glucose into pentitols D-arabitol and, especially, xylitol. The path that was chosen to achieve this goal required discovery, isolation and sequencing of at least two pentitol phosphate dehydrogenases of different specificity, followed by cloning and expression of their genes and characterization of recombinant arabitol and xylitol phosphate dehydrogenases. An enzyme of a previously unknown specificity, D-arabitol phosphate dehydrogenase (APDH), was discovered in Enterococcus avium. The enzyme was purified to homogenity from E. avium strain ATCC 33665. SDS/PAGE revealed that the enzyme has a molecular mass of 41 ± 2 kDa, whereas a molecular mass of 160 ± 5 kDa was observed under non-denaturing conditions implying that the APDH may exist as a tetramer with identical subunits. Purified APDH was found to have narrow substrate specificity, converting only D-arabitol 1-phosphate and D-arabitol 5-phosphate into D-xylulose 5-phosphate and D-ribulose 5-phosphate, respectively, in the oxidative reaction. Both NAD+ and NADP+ were accepted as co-factors. Based on the partial protein sequences, the gene encoding APDH was cloned. Homology comparisons place APDH within the medium chain dehydrogenase family. Unlike most members of this family, APDH requires Mn2+ but no Zn2+ for enzymatic activity. The DNA sequence surrounding the gene suggests that it belongs to an operon that also contains several components of phosphotransferase system (PTS). The apparent role of the enzyme is to participate in arabitol catabolism via the arabitol phosphate route similar to the ribitol and xylitol catabolic routes described previously. Xylitol phosphate dehydrogenase (XPDH) was isolated from Lactobacillus rhamnosus strain ATCC 15820. The enzyme was partially sequenced. Amino acid sequences were used to isolate the gene encoding the enzyme. The homology comparisons of the deduced amino acid sequence of L. rhamnosus XPDH revealed several similar enzymes in genomes of various species of Gram-positive bacteria. Two enzymes of Clostridium difficile and an enzyme of Bacillus halodurans were cloned and their substrate specificities together with the substrate specificity of L. rhamnosus XPDH were compared. It was found that one of the XPDH enzymes of C. difficile and the XPDH of L. rhamnosus had the highest selectivity towards D-xylulose 5-phosphate. A known transketolase-deficient and D-ribose-producing mutant of Bacillus subtilis (ATCC 31094) was further modified by disrupting its rpi (D-ribose phosphate isomerase) gene to create D-ribulose- and D-xylulose-producing strain. Expression of APDH of E. avium and XPDH of L. rhamnosus and C. difficile in D-ribulose- and D-xylulose-producing strain of B. subtilis resulted in strains capable of converting D-glucose into D-arabitol and xylitol, respectively. The D-arabitol yield on D-glucose was 38 % (w/w). Xylitol production was accompanied by co-production of ribitol limiting xylitol yield to 23 %.
  • Salmela, Viljami (Helsingin yliopisto, 2009)
    The human visual system has adapted to function in different lighting environments and responds to contrast instead of the amount of light as such. On the one hand, this ensures constancy of perception, for example, white paper looks white both in bright sunlight and in dim moonlight, because contrast is invariant to changes in overall light level. On the other hand, the brightness of the surfaces has to be reconstructed from the contrast signal because no signal from surfaces as such is conveyed to the visual cortex. In the visual cortex, the visual image is decomposed to local features by spatial filters that are selective for spatial frequency, orientation, and phase. Currently it is not known, however, how these features are subsequently integrated to form objects and object surfaces. In this thesis the integration mechanisms of achromatic surfaces were studied by psychophysically measuring the spatial frequency and orientation tuning of brightness perception. In addition, the effect of textures on the spread of brightness and the effect of phase of the inducing stimulus on brightness were measured. The novel findings of the thesis are that (1) a narrow spatial frequency band, independent of stimulus size and complexity, mediates brightness information (2) figure-ground brightness illusions are narrowly tuned for orientation (3) texture borders, without any luminance difference, are able to block the spread of brightness, and (4) edges and even- and odd-symmetric Gabors have a similar antagonistic effect on brightness. The narrow spatial frequency tuning suggests that only a subpopulation of neurons in V1 is involved in brightness perception. The independence of stimulus size and complexity indicates that the narrow tuning reflects hard-wired processing in the visual system. Further, it seems that figure-ground segregation and mechanisms integrating contrast polarities are closely related to the low level mechanisms of brightness perception. In conclusion, the results of the thesis suggest that a subpopulation of neurons in visual cortex selectively integrates information from different contrast polarities to reconstruct surface brightness.
  • Meretoja, Atte (Helsingin yliopisto, 2011)
    Stroke is a major cause of death and disability, incurs significant costs to healthcare systems, and inflicts severe burden to the whole society. Stroke care in Finland has been described in several population-based studies between 1967 and 1998, but not since. In the PERFECT Stroke study presented here, a system for monitoring the Performance, Effectiveness, and Costs of Treatment episodes in Stroke was developed in Finland. Existing nationwide administrative registries were linked at individual patient level with personal identification numbers to depict whole episodes of care, from acute stroke, through rehabilitation, until the patients went home, were admitted to permanent institutional care, or died. For comparisons in time and between providers, patient case-mix was adjusted for. The PERFECT Stroke database includes 104 899 first-ever stroke patients over the years 1999 to 2008, of whom 79% had ischemic stroke (IS), 14% intracerebral hemorrhage (ICH), and 7% subarachnoid hemorrhage (SAH). A 18% decrease in the age and sex adjusted incidence of stroke was observed over the study period, 1.8% improvement annually. All-cause 1-year case-fatality rate improved from 28.6% to 24.6%, or 0.5% annually. The expected median lifetime after stroke increased by 2 years for IS patients, to 7 years and 7 months, and by 1 year for ICH patients, to 4 years 5 months. No change could be seen in median SAH patient survival, >10 years. Stroke prevalence was 82 000, 1.5% of total population of Finland, in 2008. Modern stroke center care was shown to be associated with a decrease in both death and risk of institutional care of stroke patients. Number needed to treat to prevent these poor outcomes at one year from stroke was 32 (95% confidence intervals 26 to 42). Despite improvements over the study period, more than a third of Finnish stroke patients did not have access to stroke center care. The mean first-year healthcare cost of a stroke patient was ~20 000 , and among survivors ~10 000 annually thereafter. Only part of this cost was incurred by stroke, as the same patients cost ~5000 over the year prior to stroke. Total lifetime costs after first-ever stroke were ~85 000 . A total of 1.1 Billion , 7% of all healthcare expenditure, is used in the treatment of stroke patients annually. Despite a rapidly aging population, the number of new stroke patients is decreasing, and the patients are more likely to survive. This is explained in part by stroke center care, which is effective, and should be made available for all stroke patients. It is possible, in a suitable setting with high-quality administrative registries and a common identifier, to avoid the huge workload and associated costs of setting up a conventional stroke registry, and still acquire a fairly comprehensive dataset on stroke care and outcome.
  • Virtanen, Tea (Helsingin yliopisto, 2003)
  • Kähkipuro, Pekka (Helsingin yliopisto, 2000)
  • Lyytikäinen, Laura (Helsingin yliopisto, 2014)
    This book examines Russian civil society and democratization from the perspective of the oppositional youth activists in Moscow and St. Petersburg. It takes the Russian youth movement Oborona (Defense) as its case study. Before its dissolution in 2011, the movement was an active participant in the political opposition movement and, thus, it is an interesting case study of the actually existing activist traditions in Russia. The research shows how in Russian political activism, the Soviet continuities and liberal ideas are entangled to create new post-socialist political identities and practices. The study s findings reflect the opportunities and restrictions for activism in Russia in general, and demonstrate the specificities of Russian liberal activism as well as the reasons for the lack of wider oppositional mobilization in the country. The research draws on sociological theories on identities, social performance, and politicization as well as class, gender and generation studies. The data is derived from thematic interviews, informal discussions, participant observations, and selected readings of central Internet and social media sites. The interview data consists of 38 interviews with the activists of youth movements and it was collected in Moscow and in St Petersburg during the period of 2009 2012. In the Oborona movement, the activist identity is constructed in the intersections of the Soviet intelligentsia and dissident traditions, and international influences. On the group level, the activists sense of solidarity relies on friendship and obshchenie (communication and being together) instead of a political connectedness. Also the movement practices tend to emphasize the sense of unity by silencing individual voices and political affiliations. The movement Oborona tries to find its own way between the western imported understanding of democracy and civil society and the dominant symbolic order of sovereign democracy . The book argues that both the state s official view on democracy and Oborona s liberal-democratically oriented interpretation are tied to the political symbols of nationalism and the strong state and its unifying leader, which can be seen as a continuation of the centralized power relationships of the Soviet state. Furthermore, Oborona s repertoire of action brings together the ideals and norms of the activist identity and discursive frameworks of the movement. The book argues that the protest and its actors remain distant from the audiences and this reflects the wider problems of the political opposition and especially the liberals in Russia. The research suggests that the same weakness of collective political identity, lack of common ideological goals, leader-centeredness, and personified power that the case study illustrates are found in the Russian liberal opposition in general. Key words: Russia, political opposition, protest, youth, activism