26 resultados para health theory models

em Helda - Digital Repository of University of Helsinki


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This thesis presents an interdisciplinary analysis of how models and simulations function in the production of scientific knowledge. The work is informed by three scholarly traditions: studies on models and simulations in philosophy of science, so-called micro-sociological laboratory studies within science and technology studies, and cultural-historical activity theory. Methodologically, I adopt a naturalist epistemology and combine philosophical analysis with a qualitative, empirical case study of infectious-disease modelling. This study has a dual perspective throughout the analysis: it specifies the modelling practices and examines the models as objects of research. The research questions addressed in this study are: 1) How are models constructed and what functions do they have in the production of scientific knowledge? 2) What is interdisciplinarity in model construction? 3) How do models become a general research tool and why is this process problematic? The core argument is that the mediating models as investigative instruments (cf. Morgan and Morrison 1999) take questions as a starting point, and hence their construction is intentionally guided. This argument applies the interrogative model of inquiry (e.g., Sintonen 2005; Hintikka 1981), which conceives of all knowledge acquisition as process of seeking answers to questions. The first question addresses simulation models as Artificial Nature, which is manipulated in order to answer questions that initiated the model building. This account develops further the "epistemology of simulation" (cf. Winsberg 2003) by showing the interrelatedness of researchers and their objects in the process of modelling. The second question clarifies why interdisciplinary research collaboration is demanding and difficult to maintain. The nature of the impediments to disciplinary interaction are examined by introducing the idea of object-oriented interdisciplinarity, which provides an analytical framework to study the changes in the degree of interdisciplinarity, the tools and research practices developed to support the collaboration, and the mode of collaboration in relation to the historically mutable object of research. As my interest is in the models as interdisciplinary objects, the third research problem seeks to answer my question of how we might characterise these objects, what is typical for them, and what kind of changes happen in the process of modelling. Here I examine the tension between specified, question-oriented models and more general models, and suggest that the specified models form a group of their own. I call these Tailor-made models, in opposition to the process of building a simulation platform that aims at generalisability and utility for health-policy. This tension also underlines the challenge of applying research results (or methods and tools) to discuss and solve problems in decision-making processes.

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This study examines boundaries in health care organizations. Boundaries are sometimes considered things to be avoided in everyday living. This study suggests that boundaries can be important temporally and spatially emerging locations of development, learning, and change in inter-organizational activity. Boundaries can act as mediators of cultural and social formations and practices. The data of the study was gathered in an intervention project during the years 2000-2002 in Helsinki in which the care of 26 patients with multiple and chronic illnesses was improved. The project used the Change Laboratory method that represents a research assisted method for developing work. The research questions of the study are: (1) What are the boundary dynamics of development, learning, and change in health care for patients with multiple and chronic illnesses? (2) How do individual patients experience boundaries in their health care? (3) How are the boundaries of health care constructed and reconstructed in social interaction? (4) What are the dynamics of boundary crossing in the experimentation with the new tools and new practice? The methodology of the study, the ethnography of the multi-organizational field of activity, draws on cultural-historical activity theory and anthropological methods. The ethnographic fieldwork involves multiple research techniques and a collaborative strategy for raising research data. The data of this study consists of observations, interviews, transcribed intervention sessions, and patients' health documents. According to the findings, the care of patients with multiple and chronic illnesses emerges as fragmented by divisions of a patient and professionals, specialties of medicine and levels of health care organization. These boundaries have a historical origin in the Finnish health care system. As an implication of these boundaries, patients frequently experience uncertainty and neglect in their care. However, the boundaries of a single patient were transformed in the Change Laboratory discussions among patients, professionals and researchers. In these discussions, the questioning of the prevailing boundaries was triggered by the observation of gaps in inter-organizational care. Transformation of the prevailing boundaries was achieved in implementation of the collaborative care agreement tool and the practice of negotiated care. However, the new tool and practice did not expand into general use during the project. The study identifies two complementary models for the development of health care organization in Finland. The 'care package model', which is based on productivity and process models adopted from engineering and the 'model of negotiated care', which is based on co-configuration and the public good.

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M.A. (Educ.) Anu Kajamaa from the University of Helsinki, Center for Research on Activity, Development and Learning (CRADLE), examines change efforts and their consequences in health care in the public sector. The aim of her academic dissertation is, by providing a new conceptual framework, to widen our understanding of organizational change efforts and their consequences and managerial challenges. Despite the multiple change efforts, the results of health care development projects have not been very promising, and many developmental needs and managerial challenges exist. The study challenges the predominant, well-framed health care change paradigm and calls for an expanded view to explore the underlying issues and multiplicities of change efforts and their consequences. The study asks what kind of expanded conceptual framework is needed to better understand organizational change as transcending currently dominant oppositions in management thinking, specifically in the field of health care. The study includes five explorative case studies of health care change efforts and their consequences in Finland. Theory and practice are tightly interconnected in the study. The methodology of the study integrates the ethnography of organizational change, a narrative approach and cultural-historical activity theory. From the stance of activity theory, historicity, contradictions, locality and employee participation play significant roles in developing health care. The empirical data of the study has mainly been collected in two projects, funded by the Finnish Work Environment Fund. The data was collected in public sector health care organizations during the years 2004-2010. By exploring the oppositions between distinct views on organizational change and the multi-site, multi-level and multi-logic of organizational change, the study develops an expanded, multidimensional activity-theoretical framework on organizational change and management thinking. The findings of the study contribute to activity theory and organization studies, and provide information for health care management and practitioners. The study illuminates that continuous development efforts bridged to one another and anchored to collectively created new activity models can lead to significant improvements and organizational learning in health care. The study presents such expansive learning processes. The ways of conducting change efforts in organizations play a critical role in the creation of collective new practices and tools and in establishing ownership over them. Some of the studied change efforts were discontinuous or encapsulated, not benefiting the larger whole. The study shows that the stagnation and unexpected consequences of change efforts relate to the unconnectedness of the different organizational sites, levels and logics. If not dealt with, the unintended consequences such as obstacles, breaks and conflicts may stem promising change and learning processes.

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This thesis explores melodic and harmonic features of heavy metal, and while doing so, explores various methods of music analysis; their applicability and limitations regarding the study of heavy metal music. The study is built on three general hypotheses according to which 1) acoustic characteristics play a significant role for chord constructing in heavy metal, 2) heavy metal has strong ties and similarities with other Western musical styles, and 3) theories and analytical methods of Western art music may be applied to heavy metal. It seems evident that in heavy metal some chord structures appear far more frequently than others. It is suggested here that the fundamental reason for this is the use of guitar distortion effect. Subsequently, theories as to how and under what principles heavy metal is constructed need to be put under discussion; analytical models regarding the classification of consonance and dissonance and chord categorization are here revised to meet the common practices of this music. It is evident that heavy metal is not an isolated style of music; it is seen here as a cultural fusion of various musical styles. Moreover, it is suggested that the theoretical background to the construction of Western music and its analysis can offer invaluable insights to heavy metal. However, the analytical methods need to be reformed to some extent to meet the characteristics of the music. This reformation includes an accommodation of linear and functional theories that has been found rather rarely in music theory and musicology.

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Hypertension, obesity, dyslipidemia and dysglycemia constitute metabolic syndrome, a major public health concern, which is associated with cardiovascular mortality. High dietary salt (NaCl) is the most important dietary risk factor for elevated blood pressure. The kidney has a major role in salt-sensitive hypertension and is vulnerable to harmful effects of increased blood pressure. Elevated serum urate is a common finding in these disorders. While dysregulation of urate excretion is associated with cardiovascular diseases, present studies aimed to clarify the role of xanthine oxidoreductase (XOR), i.e. xanthine dehydrogenase (XDH) and its post-translational isoform xanthine oxidase (XO), in cardiovascular diseases. XOR yields urate from hypoxanthine and xanthine. Low oxygen levels upregulate XOR in addition to other factors. In present studies higher renal XOR activity was found in hypertension-prone rats than in the controls. Furthermore, NaCl intake increased renal XOR dose-dependently. To clarify whether XOR has any causal role in hypertension, rats were kept on NaCl diets for different periods of time, with or without a XOR inhibitor, allopurinol. While allopurinol did not alleviate hypertension, it prevented left ventricular and renal hypertrophy. Nitric oxide synthases (NOS) produce nitric oxide (NO), which mediates vasodilatation. A paucity of NO, produced by NOS inhibition, aggravated hypertension and induced renal XOR, whereas NO generating drug, alleviated salt-induced hypertension without changes in renal XOR. Zucker fa/fa rat is an animal model of metabolic syndrome. These rats developed substantial obesity and modest hypertension and showed increased hepatic and renal XOR activities. XOR was modified by diet and antihypertensive treatment. Cyclosporine (CsA) is a fungal peptide and one of the first-line immunosuppressive drugs used in the management of organ transplantation. Nephrotoxicity ensue high doses resulting in hypertension and limit CsA use. CsA increased renal XO substantially in salt-sensitive rats on a high NaCl diet, indicating a possible role for this reactive oxygen species generating isoform in CsA nephrotoxicity. Renal hypoxia, common to these rodent models of hypertension and obesity, is one of the plausible XOR inducing factors. Although XOR inhibition did not prevent hypertension, present experimental data indicate that XOR plays a role in the pathology of salt-induced cardiac and renal hypertrophy.

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Early-onset psychiatric illnesses effects scatter to academic achievements as well as functioning in familial and social environments. From a public health point of view, depressive disorders are the most significant mental health disorders that begin in adolescence. Using prospective and longitudinal design, this study aimed to increase the understanding of early-onset depressive disorders, related mental health disorders and developing substance use in a large population-derived sample of adolescent Finnish twins. The participants of this study, FinnTwin12, an ongoing longitudinal population-based study, came from Finnish families with twins born in 1983-87 (exhaustive of five birth cohorts, identified from Finland s Central Population Register). With follow-up ongoing at age 20-24, this thesis assessed adolescent mental health in the first three waves, starting from baseline age 11-12 to follow-ups at age 14 and 17½. Some 5600 twins participated in questionnaire assessments of a wide range of health related behaviors. Mental health was further assessed among an intensively studied subsample of 1852 adolescents, who completed also professionally administered interviews at age 14, which provided data for full DSM-IV/III-R (Diagnostic and Statistical Manual for Mental Health disorders, 4th and 3rd editions) diagnoses. The participation rates of the study were 87-92%. The results of the study suggest, that the diagnostic criteria for major depressive disorder (MDD) may not capture youth with clinically significant early-onset depressive conditions outside clinical settings. Milder cases of depression, namely adolescents fulfilling the diagnostic criteria for minor depressive disorder, a qualitatively similar condition to MDD with fewer symptoms are also associated with marked suicidal thoughts, plans and attempts, recurrences and a high degree of comorbidity. Prospectively and longitudinally, early-onset depressive disorders were of substantial importance in the context of other mental health disorders and substance use behaviors: These data from a large population-derived sample established a substantial overlap between early-onset depressive disorders and attention deficit hyperactivity disorder in adolescent females, both of them significantly predictive for development of substance use among girls. Only in females baseline DSM-IV ADHD symptoms were strong predictors of alcohol abuse and dependence and illicit drug use at age 14 and frequent alcohol use and illicit drug use at age 17.½ when conduct disorder and previous substance use were controlled for. Early-onset depressive disorders were also prospectively and longitudinally associated to daily smoking behavior, smokeless tobacco use, frequent alcohol use and illicit drug use and eating disorders. Analysis of discordant twins suggested that these predictive associations were independent of familial confounds, such as family income, structure and parental models. In sum, early-onset depressive disorders predict subsequent involvement of substance use and psychiatric morbidity. A heightened risk for substance use is substantial also among those depressed below categorical diagnosis of MDD. Whether early recognition and interventions among these young people hold potential for substance use prevention further in their lives has potential public health significance and calls for more research. Data from this population-derived sample with balanced representation of boys and girls, suggested that boys and girls with ADHD behaviors may differ from each other in their vulnerability to substance use and depressive disorders: the data suggest more adverse substance use outcome for girls that was not attenuated by conduct disorder or previous substance use. Further, the prospective associations of early-onset depressive disorders and future elevated levels of addictive substance use is not explained by familial factors supporting future substance use, which could have important implications for substance use prevention.

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In line with major demographic changes in other Northern European and North American countries and Australia, being nonmarried is becoming increasingly common in Finland, and the proportion of cohabiters and of persons living alone has grown in recent decades. Official marital status no longer reflects an individual s living arrangement, as single, divorced and widowed persons may live alone, with a partner, with children, with parents, with siblings, or with unrelated persons. Thus, more than official marital status, living arrangements may be a stronger discriminator of one s social bonds and health. The general purpose of this study was to deepen our current understanding of the magnitude, trends, and determinants of ill health by living arrangements in the Finnish working-age population. Distinct measures of different dimensions of poor health, as well as an array of associated factors, provided a comprehensive picture of health differences by living arrangements and helped to assess the role of other factors in the interpretation of these differences . Mortality analyses were based on Finnish census records at the end of 1995 linked with cause-of-death registers for 1996 2000. The data included all persons aged 30 and over. Morbidity analyses were based on two comparable cross-sectional studies conducted twenty years apart (the Mini-Finland Survey in 1978 80 and the Health 2000 Survey in 2000 01). Both surveys were based on nationally representative samples of Finns aged 30 and over, and benefited from high participation rates. With the exception of mortality analyses, this study focused on health differences among the working-age population (mortality in age groups 30-64 and 65 and over, self-rated health and mental health in the age group 30-64, and unhealthy alcohol use in the age group 30-54). Compared with all nonmarried groups, married men and women exhibited the best health in terms of mortality, self-rated health, mental health and unhealthy alcohol use. Cohabiters did not differ from married persons in terms of self-rated health or mental health, but did exhibit excess unhealthy alcohol use and high mortality, particularly from alcohol-related causes. Compared with the married, persons living alone or with someone other than a partner exhibited elevated mortality as well as excess poor mental health and unhealthy alcohol use. By all measures of health, men and women living alone tended to be in the worst position. Over the past twenty years, SRH had improved least among single men and women and widowed women, and most among cohabiting women. The association between living arrangements and health has many possible explanations. The health-related selection theory suggests that healthy people are more likely to enter and maintain a marriage or a consensual union than those who are unhealthy (direct selection) or that a variety of health-damaging behavioural and social factors increase the likelihood of ill health and the probability of remaining without a partner or becoming separated from one s partner (indirect selection). According to the social causation theory, marriage or cohabitation has a health-promoting effect, whereas living alone or with others than a partner has a detrimental effect on health. In this study, the role of other factors that are mainly assumed to reflect selection, appeared to be rather modest. Social support, which reflects social causation, contributed only modestly to differences in unhealthy alcohol use by living arrangements, but had a larger effect on differences in poor mental health. Socioeconomic factors and health-related behaviour, which reflect both selection and causation, appeared to play a more important role in the excess poor health of cohabiters and of persons living alone or with someone other than a partner, than of married persons. Living arrangements were strongly connected to various dimensions of ill health. In particular, alcohol consumption appeared to be of great importance in the association between living arrangements and health. To the extent that the proportion of nonmarried persons continues to grow and their health does not improve at the same rate as that of married persons, the challenges that currently nonmarried persons pose to public health will likely increase.

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Theory of developmental origins of adult health and disease proposes that experiences during critical periods of early development may have consequences on health throughout a lifespan. Thesis studies aimed to characterize associations between early growth and some components of the metabolic syndrome cluster. Participants belong to two epidemiological cohorts with data on birth measurements and, for the younger cohort, on serial recordings of weight and height during childhood. They were born as singletons between 1924-33 and 1934-44 in the Helsinki University Central Hospital, and 500 and 2003 of them, respectively, attended clinical studies at the age of 65-75 and 56-70 years, respectively. In the 65-75 year old men and women, the well-known inverse relationship between birth weight and systolic blood pressure (SBP) was confined to people who had established hypertension. Among them a 1-kg increase in birth weight was associated with a 6.4-mmHg (95% CI: 1.0 to 11.9) decrease in SBP. This relationship was further confined to people with the prevailing Pro12Pro polymorphism of the peroxisome proliferator-activated receptor-γ2 (PPARγ2) gene. People with low birth weight were more likely to receive angiotensin-converting enzyme inhibitors/angiotensin-receptor blockers (ACEI/ARB, p=0.03), and, again, this relationship was confined to the carriers of the Pro12Pro (p=0.01 for interaction). These results suggest that the inverse association between birth weight and systolic BP becomes focused in hypertensive people because pathological features of BP regulation, associated with slow fetal growth, become self-perpetuating in adult life. Insulin resistance of the Pro12Pro carriers with low birth weight may interact with the renin-angiotensin system leading to raised BP levels. Habitual physical activity protected men and women who were small at birth, and thus at increased risk for the development of type 2 diabetes, against glucose intolerance more strongly. Among subjects with birth weight ≤3000 g, the odds ratio (OR) for glucose intolerance was 5.2 (95% CI: 2.1 to 13) in those who exercised less than 3 times per week compared to regular exercisers; in those who scored their exercise light compared with moderate exercisers (defined as comparable to brisk walking) the OR was 3.5 (1.5 to 8.2). In the 56-70 year old men a 1 kg increase in birth weight corresponded to a 4.1 kg (95% CI: 3.1 to 5.1) and in women to a 2.9 kg (2.1 to 3.6) increase in adult lean mass. Rapid gain in body mass index (BMI), i.e. crossing from an original BMI percentile to a higher one, before the age of 2 years increased adult lean mass index (LMI, lean mass/height squared) without excess fat accumulation whereas rapid gain in BMI during later childhood, despite the concurrent rise in LMI, resulted in a relatively higher increase in adult body fat mass. These findings illustrate how genes, the environment and their interactions, early growth patterns, and adult lifestyle modify adult health risks which originate from early life.

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Adverse health behaviors as well as obesity are key risk factors for chronic diseases. Working conditions also contribute to health outcomes. It is possible that the effects of psychosocially strenuous working conditions and other work-related factors on health are, to some extent, explained by adverse behaviors. Previous studies about the associations between several working conditions and behavioral outcomes are, however, inconclusive. Moreover, the results are derived mostly from male populations, one national setting only, and with limited information about working conditions and behavioral risk factors. Thus, with an interest in employee health, this study was set to focus on behavioral risk factors among middle-aged employees. More specifically, the main aim was to shed light on the associations of various working conditions with health behaviors, weight gain, obesity, and symptoms of angina pectoris. In addition to national focus, international comparisons were included to test the associations across countries thereby aiming to produce a more comprehensive picture. Furthermore, a special emphasis was on gaining new evidence in these areas among women. The data derived from the Helsinki Health Study, and from collaborative partners at the Whitehall II Study, University College London, UK, and the Toyama University, Japan. In Helsinki, the postal questionnaires were mailed in 2000-2002 to employees of the City of Helsinki, aged 40 60 years (n=8960). The questionnaire data covered e.g., socio-economic indicators and working conditions such as Karasek s job demands and job control, work fatigue, working overtime, work-home interface, and social support. The outcome measures consisted of smoking, drinking, physical activity, food habits, weight gain, obesity, and symptoms of angina pectoris. The international cohorts included comparable data. Logistic regression analysis was used. The models were adjusted for potential confounders such as age, education, occupational class, and marital status subject to specific aims. The results showed that working conditions were mostly unassociated with health behaviors, albeit some associations were found. Low job strain was associated with healthy food habits and non-smoking among women in Helsinki. Work fatigue, in turn, was related to drinking among men and physical inactivity among women. Work fatigue and working overtime were associated with weight gain in Helsinki among both women and men. Finally, work fatigue, low job control, working overtime, and physically strenuous work were associated with symptoms of angina pectoris among women in Helsinki. Cross-country comparisons confirmed mostly non-existent associations. High job strain was associated with physical inactivity and smoking, and passive work with physical inactivity and less drinking. Working overtime, in turn, related to non-smoking and obesity. All these associations were, however, inconsistent between cohorts and genders. In conclusion, the associations of the studied working conditions with the behavioral risk factors lacked general patters, and were, overall, weak considering the prevalence of psychosocially strenuous work and overtime hours. Thus, based on this study, the health effects of working conditions are likely to be mediated by adverse behaviors only to a minor extent. The associations of work fatigue and working overtime with weight gain and symptoms of angina pectoris are, however, of potential importance to the subsequent health and work ability of employees.

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Nephrin is a transmembrane protein belonging to the immunoglobulin superfamily and is expressed primarily in the podocytes, which are highly differentiated epithelial cells needed for primary urine formation in the kidney. Mutations leading to nephrin loss abrogate podocyte morphology, and result in massive protein loss into urine and consequent early death in humans carrying specific mutations in this gene. The disease phenotype is closely replicated in respective mouse models. The purpose of this thesis was to generate novel inducible mouse-lines, which allow targeted gene deletion in a time and tissue-specific manner. A proof of principle model for succesful gene therapy for this disease was generated, which allowed podocyte specific transgene replacement to rescue gene deficient mice from perinatal lethality. Furthermore, the phenotypic consequences of nephrin restoration in the kidney and nephrin deficiency in the testis, brain and pancreas in rescued mice were investigated. A novel podocyte-specific construct was achieved by using standard cloning techniques to provide an inducible tool for in vitro and in vivo gene targeting. Using modified constructs and microinjection procedures two novel transgenic mouse-lines were generated. First, a mouse-line with doxycycline inducible expression of Cre recombinase that allows podocyte-specific gene deletion was generated. Second, a mouse-line with doxycycline inducible expression of rat nephrin, which allows podocyte-specific nephrin over-expression was made. Furthermore, it was possible to rescue nephrin deficient mice from perinatal lethality by cross-breeding them with a mouse-line with inducible rat nephrin expression that restored the missing endogenous nephrin only in the kidney after doxycycline treatment. The rescued mice were smaller, infertile, showed genital malformations and developed distinct histological abnormalities in the kidney with an altered molecular composition of the podocytes. Histological changes were also found in the testis, cerebellum and pancreas. The expression of another molecule with limited tissue expression, densin, was localized to the plasma membranes of Sertoli cells in the testis by immunofluorescence staining. Densin may be an essential adherens junction protein between Sertoli cells and developing germ cells and these junctions share similar protein assembly with kidney podocytes. This single, binary conditional construct serves as a cost- and time-efficient tool to increase the understanding of podocyte-specific key proteins in health and disease. The results verified a tightly controlled inducible podocyte-specific transgene expression in vitro and in vivo as expected. These novel mouse-lines with doxycycline inducible Cre recombinase and with rat nephrin expression will be useful for conditional gene targeting of essential podocyte proteins and to study in detail their functions in the adult mice. This is important for future diagnostic and pharmacologic development platforms.

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Whether a statistician wants to complement a probability model for observed data with a prior distribution and carry out fully probabilistic inference, or base the inference only on the likelihood function, may be a fundamental question in theory, but in practice it may well be of less importance if the likelihood contains much more information than the prior. Maximum likelihood inference can be justified as a Gaussian approximation at the posterior mode, using flat priors. However, in situations where parametric assumptions in standard statistical models would be too rigid, more flexible model formulation, combined with fully probabilistic inference, can be achieved using hierarchical Bayesian parametrization. This work includes five articles, all of which apply probability modeling under various problems involving incomplete observation. Three of the papers apply maximum likelihood estimation and two of them hierarchical Bayesian modeling. Because maximum likelihood may be presented as a special case of Bayesian inference, but not the other way round, in the introductory part of this work we present a framework for probability-based inference using only Bayesian concepts. We also re-derive some results presented in the original articles using the toolbox equipped herein, to show that they are also justifiable under this more general framework. Here the assumption of exchangeability and de Finetti's representation theorem are applied repeatedly for justifying the use of standard parametric probability models with conditionally independent likelihood contributions. It is argued that this same reasoning can be applied also under sampling from a finite population. The main emphasis here is in probability-based inference under incomplete observation due to study design. This is illustrated using a generic two-phase cohort sampling design as an example. The alternative approaches presented for analysis of such a design are full likelihood, which utilizes all observed information, and conditional likelihood, which is restricted to a completely observed set, conditioning on the rule that generated that set. Conditional likelihood inference is also applied for a joint analysis of prevalence and incidence data, a situation subject to both left censoring and left truncation. Other topics covered are model uncertainty and causal inference using posterior predictive distributions. We formulate a non-parametric monotonic regression model for one or more covariates and a Bayesian estimation procedure, and apply the model in the context of optimal sequential treatment regimes, demonstrating that inference based on posterior predictive distributions is feasible also in this case.

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This thesis consists of an introduction, four research articles and an appendix. The thesis studies relations between two different approaches to continuum limit of models of two dimensional statistical mechanics at criticality. The approach of conformal field theory (CFT) could be thought of as the algebraic classification of some basic objects in these models. It has been succesfully used by physicists since 1980's. The other approach, Schramm-Loewner evolutions (SLEs), is a recently introduced set of mathematical methods to study random curves or interfaces occurring in the continuum limit of the models. The first and second included articles argue on basis of statistical mechanics what would be a plausible relation between SLEs and conformal field theory. The first article studies multiple SLEs, several random curves simultaneously in a domain. The proposed definition is compatible with a natural commutation requirement suggested by Dubédat. The curves of multiple SLE may form different topological configurations, ``pure geometries''. We conjecture a relation between the topological configurations and CFT concepts of conformal blocks and operator product expansions. Example applications of multiple SLEs include crossing probabilities for percolation and Ising model. The second article studies SLE variants that represent models with boundary conditions implemented by primary fields. The most well known of these, SLE(kappa, rho), is shown to be simple in terms of the Coulomb gas formalism of CFT. In the third article the space of local martingales for variants of SLE is shown to carry a representation of Virasoro algebra. Finding this structure is guided by the relation of SLEs and CFTs in general, but the result is established in a straightforward fashion. This article, too, emphasizes multiple SLEs and proposes a possible way of treating pure geometries in terms of Coulomb gas. The fourth article states results of applications of the Virasoro structure to the open questions of SLE reversibility and duality. Proofs of the stated results are provided in the appendix. The objective is an indirect computation of certain polynomial expected values. Provided that these expected values exist, in generic cases they are shown to possess the desired properties, thus giving support for both reversibility and duality.

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The focus of this study is on statistical analysis of categorical responses, where the response values are dependent of each other. The most typical example of this kind of dependence is when repeated responses have been obtained from the same study unit. For example, in Paper I, the response of interest is the pneumococcal nasopharengyal carriage (yes/no) on 329 children. For each child, the carriage is measured nine times during the first 18 months of life, and thus repeated respones on each child cannot be assumed independent of each other. In the case of the above example, the interest typically lies in the carriage prevalence, and whether different risk factors affect the prevalence. Regression analysis is the established method for studying the effects of risk factors. In order to make correct inferences from the regression model, the associations between repeated responses need to be taken into account. The analysis of repeated categorical responses typically focus on regression modelling. However, further insights can also be gained by investigating the structure of the association. The central theme in this study is on the development of joint regression and association models. The analysis of repeated, or otherwise clustered, categorical responses is computationally difficult. Likelihood-based inference is often feasible only when the number of repeated responses for each study unit is small. In Paper IV, an algorithm is presented, which substantially facilitates maximum likelihood fitting, especially when the number of repeated responses increase. In addition, a notable result arising from this work is the freely available software for likelihood-based estimation of clustered categorical responses.

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This thesis studies homogeneous classes of complete metric spaces. Over the past few decades model theory has been extended to cover a variety of nonelementary frameworks. Shelah introduced the abstact elementary classes (AEC) in the 1980s as a common framework for the study of nonelementary classes. Another direction of extension has been the development of model theory for metric structures. This thesis takes a step in the direction of combining these two by introducing an AEC-like setting for studying metric structures. To find balance between generality and the possibility to develop stability theoretic tools, we work in a homogeneous context, thus extending the usual compact approach. The homogeneous context enables the application of stability theoretic tools developed in discrete homogeneous model theory. Using these we prove categoricity transfer theorems for homogeneous metric structures with respect to isometric isomorphisms. We also show how generalized isomorphisms can be added to the class, giving a model theoretic approach to, e.g., Banach space isomorphisms or operator approximations. The novelty is the built-in treatment of these generalized isomorphisms making, e.g., stability up to perturbation the natural stability notion. With respect to these generalized isomorphisms we develop a notion of independence. It behaves well already for structures which are omega-stable up to perturbation and coincides with the one from classical homogeneous model theory over saturated enough models. We also introduce a notion of isolation and prove dominance for it.

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Although shame is a universal human emotion and is one of the most difficult emotions to overcome, its origins and nature as well as its effects on psychosocial functioning are not well understood or defined. While psychological and spiritual counselors are aware of the effects and consequences of shame for an individual s internal well-being and social life, shame is often still considered a taboo topic and is not given adequate attention. This study aims to explain the developmental process and effects of shame and shame-proneness for individuals and provide tools for practitioners to work more effectively with their clients who struggle with shame. This study presents the empirical foundation for a grounded theory that describes and explains the nature, origins, and consequences of shame-proneness. The study focused on Finnish participants childhood, adolescence and adulthood experiences and why they developed shame-proneness, what it meant for them as children and adolescents and what it meant for them as adults. The data collection phase of this study began in 2000. The participants were recruited through advertisements in local and country-wide newspapers and magazines. Altogether 325 people responded to the advertisements by sending an essay concerning their shame and guilt experiences. For the present study, 135 essays were selected and from those who sent an essay 19 were selected for in-depth interviews. In addition to essays and interviews, participants personal notebooks and childhood hospital and medical reports as well as their scores on the Internalized Shame Scale were analyzed. The development of shame-proneness and significant experiences and events during childhood and adolescence (e.g., health, parenting and parents behavior, humiliation, bullying, neglect, maltreatment and abuse) are discussed and the connections of shame-proneness to psychological concepts such as self-esteem, attachment, perfectionism, narcissism, submissiveness, pleasing others, heightened interpersonal subjectivity, and codependence are explained. Relationships and effects of shame-proneness on guilt, spirituality, temperament, coping strategies, defenses, personality formation and psychological health are also explicated. In addition, shame expressions and the development of shame triggers as well as internalized and externalized shame are clarified. These connections and developments are represented by the core category lack of gaining love, validation and protection as the authentic self. The conclusions drawn from the study include a categorization of shame-prone Finnish people according to their childhood and adolescent experiences and the characteristics of their shame-proneness and personality. Implications for psychological and spiritual counseling are also discussed. Key words: shame, internalized shame, external shame, shame development, shame triggers, guilt, self-esteem, attachment, narcissism, perfectionism, submissiveness, codependence, childhood neglect, childhood abuse, childhood maltreatment, emotional abuse, sexual abuse, spiritual abuse, psychological well-being