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  • Karhula, Kati (Helsingin yliopisto, 2015)
    Health care personnel often have irregular working hours and stressful work characteristics, which may challenge employees possibilities to sleep and recover sufficiently. The aim of this study was to examine the association of stressful work characteristics, measured as job strain, with sleep and psychophysiological recovery in shift working health care professionals. As part of the Finnish Public Sector Study, 95 participants were recruited from hospital wards that belonged to the top (high job strain, HJS, n=42) or bottom quartiles on job strain (low job strain, LJS, n=53) as determined by the average job strain score among the employees of the ward. These participants experienced job strain at least as high (HJS group) or as low (LJS group) as the average on their ward. Measurements included a Trier Social Stress Test (TSST), and 3-week field measures of sleep-wake rhythm with sleep diary and actigraphy. The 3-week rosters included three pre-selected, circadian rhythm and recovery controlled measurement days, one morning shift, one night shift and a day off, and the following measurements: ratings of sleepiness (Karolinska Sleepiness Scale), Psychomotor Vigilance Test (PVT), 24h heart rate variability (HRV) measurements and saliva samples of stress biomarkers (cortisol and alpha-amylase). The rosters of the HJS group included more single days off and quick returns than the rosters of the LJS group. Severe sleepiness (KSS score of ≥7) was more common in the HJS group in quick returns. The HJS group reported poorer recovery from all work shifts and after morning shifts than the LJS group. High job strain was not associated with extended working hours. The HJS group had more difficulties in initiating sleep after evening shifts, more often reduced sleep efficiency before morning shifts, and took fewer and shorter naps before the first night shift than the LJS group. Additionally, the HJS group had more often lapses in the PVT during night shifts. Insufficient sleep (31%) and sleep complaints (often 68%) were common in shift workers regardless of the job strain group. The TSST resulted in, on average, a 2.27-fold increase in cortisol concentration in the HJS group and a 1.48-fold increase in the LJS group (non-significant group difference). The HJS group also had higher salivary alpha-amylase levels 30 minutes after awakening in the morning shift. Apart from that, the salivary cortisol and alpha-amylase levels, profiles and total secretion showed no statistically significant stress group differences. Heart rate and HRV, before and during sleep, were similar in both job strain groups. Shift work contributed to impaired sleep in both the high and low job strain groups, although the sleep impairments were more pronounced in the HJS group. Associations between job strain and psychophysiological stress-related reactions and recovery were modest. Intervention studies are needed to determine whether increasing recovery time by reducing the number of quick returns and single days off would also reduce job strain and improve sleep quality among shift workers. Emphasising the importance of sufficient sleep might promote shift workers´ recovery and well-being.
  • Lawson, Tom (2000)
    Body weight is closely related to several known cardiovascular risk factors and may also have an independent effect on the risk of coronary heart disease (CHD). The cardiovascular risk factor levels of the Finnish population have been assessed in Finland since 1972, though in the beginning the surveys were done to evaluate the North Karelia Project, which was a community-based preventive program and a National cardiovascular risk factors monitoring system was developed to assess the effectiveness of the national strategy. The purpose of this report was to examine cross-sectional data to assess the independent contribution of Body mass index (BMI) and Waist-hip-ratio (WHR) to the risk of Cardiovascular disease (CVD) and to find out the importance of WHR for the incidence of chronic diseases in 4110 Finnish men and 4084 Finnish women between the ages 25-74 years old who were participants in the 1997 examinations of FINMONICA-Project and were not treated for with cardiovascular medication. BMI was used as a measure of obesity and WHR as fat distribution measurements and both were adjusted for age, on cholesterols, and blood pressures in separate models for men and women in the data. Obesity were estimated from body weight, height and the body fat from skinfold-thickness measurements. The analysis is confined to the relationships between the risk factors and this risk factors was divided into two groups, the first consisting of the operational measures of cholesterols level and blood pressures respectively High density lipoprotein cholesterol (HDL), Non high density lipoprotein cholesterol (NHDL), Ratio of HDL and NHDL (HNR), Systollinen blood pressure (SYS1) and Diastollinen blood pressure (DIAS1), while the second consist of obesity (BMI) and body fat (WHR). The analysis was done to study the interaction effect of obesity and body fat on cholesterols level and blood pressures. BMI and WHR interaction effect was only significant in NHDL (P > 0.0071) and almost significant in HNR (P > 0.0789) in men and no significant interaction in women. This gender difference could easily have been overlooked if gender had been included in the analyses of variance as an explanatory factor.
  • Komulainen, Kaisla (Helsingin yliopisto, 2015)
    Adolescent delinquency is a prevalent concern, which carries with psychological and societal costs. Deviant peer affiliation and criminogenic attitudes, as well as personality traits are known to be associated with delinquency, but their interlinked effects are less studied. The present study examines the role of personality in a deviant socialization context. Specifically, I examine whether peer deviance and criminogenic attitudes (1) mediate and/or (2) moderate the associations of the Five-Factor Model personality traits with delinquency. The data included respondents (n=4855) to the cross-sectional Finnish Self-Report Delinquency Study 2012, aged 14-17 years. Delinquency was assessed on the basis of 17 different deviant behaviors; the reported frequencies of engaging in each of them were scaled using a graded response model. Peer deviance and criminogenic attitudes were assessed via respondents’ selfreports; two distinct attitudinal indicators (deviant and neutralizing attitudes) were included. Personality was assessed with a 15-item BFI-S questionnaire. A structural equation model was conducted to examine the mediation pathways. The moderation effects were examined with linear regression analysis. Delinquency was associated with higher extraversion, lower agreeableness, lower conscientiousness, and lower neuroticism. Peer deviance and criminogenic attitudes partially mediated the associations of extraversion, agreeableness, and conscientiousness with delinquency. The association between neuroticism and delinquency was fully mediated via criminogenic attitudes. Peer deviance strengthened the associations of low neuroticism, low agreeableness, and low conscientiousness with delinquency. Deviant and neutralizing attitudes strengthened the associations of high extraversion and low agreeableness with delinquent conduct. The findings suggest that personality may provide novel insights into the etiology of delinquency in a context of deviant socialization. Implications of the personality-based approach and directions for further research are discussed.
  • Laaksonen , Matti (Helsingin yliopisto, 2010)
    The Enamel matrix derivative Emdogain® (EMD) is a commercially available tissue extract preparation of porcine enamel origin. Studies have shown EMD to be clinically useful in promoting periodontal regeneration. EMD has been widely used in periodontal therapy for over ten years, but the mechanism of its action and the exact composition are not completely clear. EMD is predominantly amelogenin (>90%). However, unlike amelogenin, EMD has a number of growth factor-like effects and it has been shown to enhance the proliferation, migration and other cellular functions of periodontal ligament fibroblasts and osteoblasts. In contrast, the effects of EMD on epithelial cell lines and in particular on oral malignant cells have not been adequately studied. In addition, EMD has effects on the production of cytokines by several oral cell lines and the product is in constant interaction with different oral enzymes. Regardless of the various unknown properties of EMD, it is said to be clinically safe in regenerative procedures, also in medically compromised patients. The aim of the study was to examine whether gingival crevicular fluid (GCF), which contains several different proteolysis enzymes, could degrade EMD and alter its biological functions. In addition, the objective was to study the effects of EMD on carcinogenesis-related factors, in particular MMPs, using in vitro and in vivo models. This study also aimed to contribute to the understanding of the composition of EMD. GCF was capable of degrading EMD, depending on the periodontal status, with markedly more degradation in all states of periodontal disease compared to healthy controls. EMD was observed to stimulate the migration of periodontal ligament fibroblasts (PLF), whereas EMD together with GCF could not stimulate this proliferation. In addition, recombinant amelogenin, the main component of EMD, decreased the migration of PLFs. A comparison of changes induced by EMD and TGF-β1 in the gene profiles of carcinoma cells showed TGF-β1 to regulate a greater number of genes than EMD. However, both of the study reagents enhanced the expression of MMP-10 and MMP-9. Furthermore, EMD was found to induce several factors closely related to carcinogenesis on gene, protein, cell and in vivo levels. EMD enhanced the production of MMP-2, MMP-9 and MMP-10 proteins by cultured carcinoma cells. In addition, EMD stimulated the migration and in vitro wound closure of carcinoma cells. EMD was also capable of promoting metastasis formation in mice. In conclusion, the diseased GCF, containing various proteases, causes degradation of EMD and decreased proliferation of PLFs. Thus, this in vitro study suggests that the regenerative effect of EMD may decrease due to proteases present in periodontal tissues during the inflammation and healing of the tissues in vivo. Furthermore, EMD was observed to enhance several carcinoma-related factors and in particular the production of MMPs by benign and malignant cell lines. These findings suggest that the clinical safety of EMD with regard to dysplastic mucosal lesions should be further investigated.
  • Lallukka, Tea (Helsingin yliopisto, 2008)
    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.
  • Martikainen, Silja (Helsingin yliopisto, 2010)
    This thesis examines the associations between personality traits and sleep quantity and quality in young adults. Additionally the possible effects of birth status on these associations are examined. The data used in this thesis is part of a birth cohort study (Helsinki Study of Very Low Birth Weight Adults). The personality traits are based on the five-factor model of personality. The sleep quantity and quality are based on actigraphy assessments. Four hypothesis were made about the personality and sleep associations: (1) neuroticism is related to a lesser quality of sleep, (2) there will be more significant associations between personality traits and sleep quality than between personality traits and sleep quantity, (3) the Very Low Birth Weight (VLBW) as well as, (4) the Small for Gestational Age (SGA) status will affect the associations. Linear regressions were used to study the associations between personality traits and sleep quality and quantity. Whenever an association was significant, it was tested whether this association was moderated first, by the VLBW and second, by the SGA status of the participant. The results were mostly in line with previous research especially demonstrating the negative association between neuroticism and the quality of sleep and suggesting that vulnerability to stress decreases sleep quality. Also it was found that agreeableness and conscientiousness were associated with better sleep quality and extraversion was associated with lower sleep quantity. In addition SGA status moderated the personality and sleep associations. It is proposed that there are two factors behind the interaction. First, prenatally developing mechanisms have an effect on the development of sleep as well as personality. Second, differences in the postnatal environment, for instance the parenting practices, can account for this finding. Future research could focus especially on what kind of prenatal disturbances SGA infants have in the development of mechanisms related to sleep and personality. Also focusing on the differences in parental interaction might shed more light on the results.
  • Laaksonen, Marika (Helsingin yliopisto, 2008)
    Heredity explains a major part of the variation in calcium homeostasis and bone strength, and the susceptibility to osteoporosis is polygenetically regulated. Bone phenotype results from the interplay between lifestyle and genes, and several nutritional factors modulate bone health throughout life. Thus, nutrigenetics examining the genetic variation in nutrient intake and homeostatic control is an important research area in the etiology of osteoporosis. Despite continuing progress in the search for candidate genes for osteoporosis, the results thus far have been inconclusive. The main objective of this thesis was to investigate the associations of lactase, vitamin D receptor (VDR), calcium sensing receptor (CaSR) and parathyroid hormone (PTH) gene polymorphisms and lifestyle factors and their interactions with bone health in Finns at varying stages of the skeletal life span. Markers of calcium homeostasis and bone remodelling were measured from blood and urine samples. Bone strength was measured at peripheral and central bone sites. Lifestyle factors were assessed with questionnaires and interviews. Genetic lactase non-persistence (the C/C-13910 genotype) was associated with lower consumption of milk from childhood, predisposing females in particular to inadequate calcium intake. Consumption of low-lactose milk and milk products was shown to decrease the risk for inadequate calcium intake. In young adulthood, bone loss was more common in males than in females. Males with the lactase C/C-13910 genotype may be more susceptible to bone loss than males with the other lactase genotypes, although calcium intake predicts changes in bone mass more than the lactase genotype. The BsmI and FokI polymorphisms of the VDR gene were associated with bone mass in growing adolescents, but the associations weakened with age. In young adults, the A986S polymorphism of the calcium sensing receptor gene was associated with serum ionized calcium concentrations, and the BstBI polymorphism of the parathyroid gene was related to bone strength. The FokI polymorphism and sodium intake showed an interaction effect on urinary calcium excretion. A novel gene-gene interaction between the VDR FokI and PTH BstBI gene polymorphisms was found in the regulation of PTH secretion and urinary calcium excretion. Further research should be carried out with more number of Finns at varying stages of the skeletal life span and more detailed measurements of bone strength. Research should concern mechanisms by which genetic variants affect calcium homeostasis and bone strength, and the role of diet-gene and gene-gene interactions in the pathogenesis of osteoporosis.
  • Luotola, Kari (Helsingin yliopisto, 2011)
    The upstream proinflammatory interleukin-1 (IL-1) cytokines, together with a naturally occurring IL-1 receptor antagonist (IL-1Ra), play a significant role in several diseases and physiologic conditions. The IL-1 proteins affect glucose homeostasis at multiple levels contributing to vascular injuries and metabolic dysregulations that precede diabetes. An association between IL-1 gene variations and IL-1Ra levels has been suggested, and genetic studies have reported associations with metabolic dysregulation and altered inflammatory responses. The principal aims of this study were to: 1) examine the associations of IL-1 gene variation and IL-1Ra expression in the development and persistence of thyroid antibodies in subacute thyroiditis; 2) investigate the associations of common variants in the IL-1 gene family with plasma glucose and insulin concentrations, glucose homeostasis measures and prevalent diabetes in a representative population sample; 3) investigate genetic and non-genetic determinants of IL-1Ra phenotypes in a cross-sectional setting in three independent study populations; 4) investigate in a prospective setting (a) whether variants of the IL-1 gene family are predictors for clinically incident diabetes in two population-based observational cohort studies; and (b) whether the IL-1Ra levels predict the progression of metabolic syndrome to overt diabetes during the median follow-up of 10.8 and 7.1 years. Results from on patients with subacte thyroiditis showed that the systemic IL-1Ra levels are elevated during a specific proinflammatory response and they correlated with C-reactive protein (CRP) levels. Genetic variation in the IL-1 family seemed to have an association with the appearance of thyroid peroxidase antibodies and persisting local autoimmune responses during the follow-up. Analysis of patients suffering from diabetes and metabolic traits suggested that genetic IL-1 variation and IL-1Ra play a role in glucose homeostasis and in the development of type 2 diabetes. The coding IL-1 beta SNP rs1143634 was associated with traits related to insulin resistance in cross-sectional analyses. Two haplotype variants of the IL-1 beta gene were associated with prevalent diabetes or incident diabetes in a prospective setting and both of these haplotypes were tagged by rs1143634. Three variants of the IL-1Ra gene and one of the IL-1 beta gene were consistently identified as significant, independent determinants of the IL-1Ra phenotype in two or three populations. The proportion of the phenotypic variation explained by the genetic factors was modest however, while obesity and other metabolic traits explained a larger part. Body mass index was the strongest predictor of systemic IL-1Ra concentration overall. Furthermore, the age-adjusted IL-1Ra concentrations were elevated in individuals with metabolic syndrome or diabetes when compared to those free of metabolic dysregulation. In prospective analyses the systemic IL-1Ra levels were found as independent predictors for the development of diabetes in people with metabolic syndrome even after adjustment for multiple other factors, including plasma glucose and CRP levels. The predictive power of IL-1Ra was better than that of CRP. The prospective results also provided some evidence for a role of common IL-1 alpha promoter SNP rs1800587 in the development of type 2 diabetes among men and suggested that the role may be gender specific. Likewise, common variations in the IL-1 beta coding region may have a gender specific association with diabetes development. Further research on the potential benefits of IL-1Ra measurements in identifying individuals at high risk for diabetes, who then could be targeted for specific treatment interventions, is warranted. It has been reported in the recent literature that IL-1Ra secreted from adipose tissue has beneficial effects on glucose homeostasis. Furthermore, treatment with recombinant human IL-1Ra has been shown to have a substantial therapeutic potential. The genetic results from the prospective analyses performed in this study remain inconclusive, but together with the cross-sectional analyses they suggest gender-specific effects of the IL-1 variants on the risk of diabetes. Larger studies with more extensive genotyping and resequencing may help to pinpoint the exact variants responsible and to further elucidate the biological mechanisms for the observed associations. This would improve our understanding of the pathways linking inflammation and obesity with glucose and insulin metabolism.
  • Keinänen, Juho (Helsingfors universitet, 2014)
    Työntekijöiden vapaalla liikkuvuudella on Euroopan unionin yhtenä sisämarkkinavapautena vakiintunut asema eurooppaoikeudessa. Jäsenvaltioiden kansalaisten subjektiivinen oikeus etsiä ja tehdä työtä toisen jäsenvaltion alueella ja nauttia yhdenvertaisesta kohtelusta vastaanottavan jäsenvaltion omien kansalaisten kanssa on turvattu perussopimuksissa, johdetussa oikeudessa ja EU-tuomioistuimen oikeuskäytännössä. Vapaaseen liikkuuvuuteen liittyviin oikeuksiin vetoaminen edellyttää kuitenkin jäsenvaltion kansalaisuutta. Mikäli jäsenvaltion alueella työskentelevä kolmannen valtion kansalainen ei ole liikkumisvapauttaan käyttäneen EU-kansalaisen perheenjäsen, kolmannen valtion kansalainen voi kuitenkin vedota EU:n oikeusjärjestykseen kuuluviin kansainvälisiin sopimuksiin ja unionin työperäistä maahanmuuttoa koskevaan sekundaarilainsäädäntöön. Tutkielmassa tarkastellaan kolmansien valtioiden kansalaisten asemaa unionin solmimien ulkosopimusten ja yhteistä maahanmuuttopolitiikkaa toteuttavan sekundaarilainsäädännön perusteella sekä näiden oikeuslähteiden välisiä suhteita. Assosiaatiosopimuksilla on perustettu etuoikeutettuja yhteyksiä EU:n ja sen jäsenvaltioiden sekä kolmansien valtioiden välille. Sopimuksissa on voitu määrätä muun muassa sopimuspuolten kansalaisten työskentely- ja oleskeluoikeudesta jäsenvaltioissa sekä oikeudesta yhdenvertaiseen kohteluun vastaanottavan jäsenvaltion omien kansalaisten kanssa. Sopimuksissa turvattujen oikeuksien laajuus kuitenkin vaihtelee, siten kolmansien valtioiden kansalaiset ovat kansalaisuutensa perusteella eriarvoisessa asemassa. EU-tuomioistuimen oikeuskäytännön mukaan työntekijöiden asemaa koskevat sopimusmääräykset ovat välittömästi vaikuttavia kansallisissa oikeusjärjestyksissä mikäli ne asettavat selkeitä, ehdottomia ja tulevista täytäntöönpanotoimista riippumattomia velvoitteita, eikä välittömän vaikutuksen myöntäminen ole sopimuksen tavoitteiden tai luonteen vastaista. EU-tuomioistuin on myöntänyt tavoitteiltaan hyvin erilaisiin sopimuksiin sisältyville määräyksille välittömän vaikutuksen. Tuomioistuin on korostanut ulkosopimuksia koskevassa oikeuskäytännössä erityisesti sopimusmääräysten tehokkaan toteutumisen merkitystä. Tämän lisäksi tuomioistuin on tulkinnut määräysten jäsenvaltioille asettamien velvollisuuksien ulottuvuutta analogisesti työntekijöiden vapaata liikkuvuutta koskevan SEUT 45 artiklan kanssa riippumatta siitä, minkälaiseen sopimuskokonaisuuteen tulkittava sopimusmääräys liittyy. EU:n yhteistyö oikeus- ja sisäasioissa tähtää vapauden, turvallisuuden ja oikeuden alueen perustamiseen. Tämän osana unionin tehtäväksi on SEUT 79 artiklassa asetettu yhteisen maahanmuuttopolitiikan kehittäminen. Työperäistä maahanmuuttoa kolmansista maista säännellään sektorikohtaisen lainsäädännön takia usealla säädöksellä työntekijäryhmäkohtaisesti. Tutkielmassa käydään läpi direktiivien sisältöä sekä arvioidaan sitä, miten hyvin säädöksillä on ratkaistu ne ongelmat, joihin niillä on pyritty vaikuttamaan. Koska työperäistä maahanmuuttoa koskeva sekundaarinormisto on uutta, säädöksiä koskevaa oikeuskäytäntöä ei vielä ole kertynyt. Tutkielmassa käsitellään tämän vuoksi perheenyhdistämisdirektiiviä ja pitkään oleskelleiden kolmansien valtioiden kansalaisten asemasta annettua direktiiviä koskevaa oikeuskäytäntöä. Laillista maahanmuuttoa koskevassa oikeuskäytännössä on assosiaatiosopimuksia koskevan oikeuskäytännön tavoin korostettu säädösten tavoitteiden tehokkaan toteutumisen merkitystä ja rajoitettu jäsenvaltioiden harkintavaltaa. Lisäksi EU-tuomioistuin on oikeuskäytännössä luonut yhteyksiä EU-kansalaisten liikkumisvapauteen liittyvien oikeuksien ja sekundaarioikeudessa turvattujen kolmansien valtioiden kansalaisten oikeuksien välillä. Tutkielmassa pohditaan EU-tuomioistuimen ratkaisujen taustalla vaikuttavia syitä ja tavoitteita sekä sitä, voidaanko oikeuskäytännön perusteella ennakoida työperäistä maahanmuuttoa koskevien direktiivien vaikutuksia niiden soveltamisalaan kuuluvien kolmansien valtioiden kansalaisten oikeusasemaan ja jäsenvaltioiden velvollisuuksiin. Maahanmuuttoa koskeva sekundaarinormisto on kansainvälisiin sopimuksiin nähden toissijaista sääntelyä, sillä direktiivit eivät estä kansainvälisistä sopimuksista johtuvien suotuisampien säännösten soveltamista. Johdetun oikeuden tulkinnan tulee olla sopusoinnussa unionia ja jäsenvaltioita sitovien kansainvälisten velvoitteiden kanssa. Tutkielman lopuksi käydään läpi esimerkkejä kansainvälisten sopimusten etusijan vaikutuksista työperäistä maahanmuuttoa koskevan sekundaarinormiston tulkintaan.
  • Nikkonen, Henri (Helsingfors universitet, 2014)
    The aim of this study is to observe what kind of environmental impacts are caused by agriculture and what kind of factors causes them. The study is part of ENREFOOD – project, which views the environmental responsibility of food chain. The data was collected from scientific literature and a group interview, where participants were representing experts from different areas of primary production. The experts were shown a draft of the main environmental impacts and their causes basing on life cycle assessment (LCA) impact classes. The chosen main environmental impacts were focusing on climate change, acidification, eutrophication, biodiversity, toxicity and eco-toxicity and natural resources. The experts were supposed to modify this draft in order to achieve their collective perspective. The results were presented as comparing the draft based on scientific literature and perspectives obtained from the experts. Moreover, the terms used when discussing about the causes of the environmental impacts were analysed applying environmental protection process (EPP) framework, which can be used to illustrate how an environmental change is formed. The perspective of experts did not differ much from the scientific literature based on the draft. The names of the main environmental impact classes were slightly modified and one new class was formed. The new class was called landscape change and recreational factors. The terms relating to the causes used by experts were representing different components in the EPP framework. A Part of the terms were more abstract background factors whereas some related direct on farm level action and its emissions. The amount of the environmental impacts of primary production is huge. By more precisely scoping of the chosen environmental themes can result more manageable overall view. For example, as a good starting point the protection areas applied in the end point modelling of the LCA can be recommended. These areas of protection can be, e.g., human health, biodiversity, natural resources and natural environments. Focusing on these areas of protection separately can reduce the causality problem, which makes environmental impact observation challenging.
  • Holmqvist, Mats (2010)
    This thesis studies the political process in Pakistan between 1988 and 1999. The aim of the study is to explain why the transition to democracy failed during this period. Three major problems have been singled out for this purpose: the ethnic structure, the political structure and the role of the military. The thesis also shows how similar problems have appeared throughout Pakistan’s history and for this reason the obstacles to democracy are described as long-term, structural problems. Pakistan’s role as a frontline state in global anti-terrorist efforts has prompted a need for fresh perspectives on the country’s political development. Previous research on Pakistan is characterized as lacking historical understanding. Therefore this thesis attempts to provide a historical dimension by tracing the roots of Pakistan’s political problems. The primary sources for the thesis consist of autobiographical material, speeches, interviews and party manifestos, but the argumentation relies heavily on secondary sources. The theoretical sections of the thesis consult e.g. Dahl, Linz and Stepan for definitions of democracy and democratic transitions, Huntington for the concept of political institutionalisation and Koonings & Kruijt for approaches to political armies. The main result of the thesis is that although Pakistan began a democratic transition in 1988, it was never completed and the political process was rather more like a “nontransition”. Above all, the transition was severely constrained from the outset. The greatest obstacle to democratization was arguably the Pakistani military’s consistent interference in politics through a constitutional amendment enacted during military rule in 1985. Moreover, the lack of commitment to democratic values among the political elite puts into question whether there was a movement towards democracy at all during this period. The inability or unwillingness of successive governments to address the ethnic and regional cleavages in Pakistani society as political issues rather than law and order issues also served to undermine the legitimacy of the entire political system. The thesis concludes that the same problems seem to have halted democratic initiatives in Pakistan since the country became independent in 1947; it therefore seems likely that they will also persist unless the underlying issues are specifically addressed.
  • Christersson, Jenni (Helsingin yliopisto, 2015)
    This case study sheds new light on rural water use and related social, aconomic and environmental dimensions and proposes government intervention in order to ensure water rights and protect public value of fairness. The aim is to highlight farmers’ perspectives on irrigation water use and related obstacles, and specifically distinguish if views are connected to farmers’ underlying socioeconomic or agro-ecologic factors. For further considerations adaptive capacity of community for irrigation water fees is explored. The research material consists of semi-structured interviews for farmers (n=63), government organizations (n=3) and agricultural enterprises (n=2). Economic groups were formed via analysis of asset-based economic status. Grouping based on agricultural water use was conducted through categorization. Costs and lack of knowledge were identified as the main barriers for adopting advanced irrigation technology. The study showed prevailing allocation system is in need of reformation. When designing rural policy, farmers’ perceptions should be respected. Water allocation is considered unfair community-wide and social conflicts are largely faced. Those who do not suffer from conflicts are most commonly rich. Technology transfer offer potential benefits, but community needs to be mobilized. Grouping based on irrigation water usage may be used for targeting policies. Economic grouping may be used for distinguishing farmers’ behavior when designing change in economic conditions or conflict resolution strategy. The complementary role of this study is to bring out special focus on development for institutional capacity-building; strengthening the forcing nature of laws and user rights. This may reduce the attractiveness for corruption in the process. Under these conditions, the greatest benefits may be obtained by giving top priority instead of irrigation improvement, but conflict mediation and establishment of water markets.
  • Oszkiewicz, Dagmara (2012)
    Planetary Science belongs to the so-called fundamental sciences, which do not have to have immediate practical applications or implications. The recent decades have however shown that the study of asteroids may have direct implications on our life. Studies of asteroid dynamics have shown that some of those objects can collide with the Earth. Studies of asteroid mineralogy suggest that some of them contain minerals and elements important for industry. For both of those topics, determining physical and dynamical properties is crucial. Markov-chain Monte Carlo methods and algorithms such as the Metropolis-Hastings algorithm are growing in popularity and becoming important tools in deriving model parameters in many branches of science today. In this thesis, Bayesian statistics along with the above-mentioned numerical methods have been used to infer dynamical and physical properties of asteroids. First, a new Markov-chain Monte Carlo ranging method is developed for computing asteroid orbits. The method is applicable for asteroids with short observational time intervals and/or small number of observations. The method is particularly useful in deriving orbits for new asteroid discoveries and computing collision probabilities for such objects. The Markov-chain Monte Carlo ranging method is applied to a number of asteroids including a recent Earth impactor - asteroid 2008 TC3. Markov-chain Monte Carlo ranging is available through the open-source orbit-computation package called OpenOrb and is implemented into the Gaia satellite data processing pipeline, where it will be heavily used in the daily data processing. Second, Markov-chain Monte Carlo and Monte Carlo methods are used to assess phase curve photometric parameters and their uncertainties. Absolute magnitudes and photometric parameters are derived for half a million asteroids by fitting phase curves to the Lowell Observatory photometric database. Asteroid phase curves depend on physical properties of regolith and absolute magnitudes are useful in computing sizes and albedos. Fitting the phase functions to a large number of asteroid families suggests homogeneity of photometric parameters in asteroid families. The derived photometric parameters are also found to correspond to asteroid taxonomic complexes and colors.
  • Granvik, Mikael (Helsingin yliopisto, 2003)
  • Granvik, Mikael (Helsingin yliopisto, 2007)
    An efficient and statistically robust solution for the identification of asteroids among numerous sets of astrometry is presented. In particular, numerical methods have been developed for the short-term identification of asteroids at discovery, and for the long-term identification of scarcely observed asteroids over apparitions, a task which has been lacking a robust method until now. The methods are based on the solid foundation of statistical orbital inversion properly taking into account the observational uncertainties, which allows for the detection of practically all correct identifications. Through the use of dimensionality-reduction techniques and efficient data structures, the exact methods have a loglinear, that is, O(nlog(n)), computational complexity, where n is the number of included observation sets. The methods developed are thus suitable for future large-scale surveys which anticipate a substantial increase in the astrometric data rate. Due to the discontinuous nature of asteroid astrometry, separate sets of astrometry must be linked to a common asteroid from the very first discovery detections onwards. The reason for the discontinuity in the observed positions is the rotation of the observer with the Earth as well as the motion of the asteroid and the observer about the Sun. Therefore, the aim of identification is to find a set of orbital elements that reproduce the observed positions with residuals similar to the inevitable observational uncertainty. Unless the astrometric observation sets are linked, the corresponding asteroid is eventually lost as the uncertainty of the predicted positions grows too large to allow successful follow-up. Whereas the presented identification theory and the numerical comparison algorithm are generally applicable, that is, also in fields other than astronomy (e.g., in the identification of space debris), the numerical methods developed for asteroid identification can immediately be applied to all objects on heliocentric orbits with negligible effects due to non-gravitational forces in the time frame of the analysis. The methods developed have been successfully applied to various identification problems. Simulations have shown that the methods developed are able to find virtually all correct linkages despite challenges such as numerous scarce observation sets, astrometric uncertainty, numerous objects confined to a limited region on the celestial sphere, long linking intervals, and substantial parallaxes. Tens of previously unknown main-belt asteroids have been identified with the short-term method in a preliminary study to locate asteroids among numerous unidentified sets of single-night astrometry of moving objects, and scarce astrometry obtained nearly simultaneously with Earth-based and space-based telescopes has been successfully linked despite a substantial parallax. Using the long-term method, thousands of realistic 3-linkages typically spanning several apparitions have so far been found among designated observation sets each spanning less than 48 hours.
  • Penttilä, Antti (2009)
    Työssä tutkitaan asteroidien ja komeettojen polarisaatiota ja eteenkin polarisaatiohavainnoille sovitettavia malleja. Työn tarkoituksena on vertailla olemassa olevia polarisaatiomalleja ja niiden ominaisuuksia. Vertailun perusteella voidaan suositella jotain tiettyä mallia sekä sovitustekniikkaa erityyppisille polarisaatiohavaintoaineistoille ja tutkimusasetelmille. Polarisaatiolla tarkoitetaan tässä nimenomaan lineaarista polarisaatiosuhdetta. Aurinko lähettää kohteeseen, tässä työssä joko asteroidiin tai komeettaan, valoa tai yleisemmin sähkömagneettista säteilyä jossa kaikki lineaariset polarisaatiotasot ovat tasaisesti edustettuna, ns. polarisoitumatonta valoa. Kohteen pinta voi kuitenkin sirottaa eri polarisaatiotasoissa olevaa säteilyä eri voimakkuuksilla, jolloin sironnut säteily on polarisoitunutta. Sironneen säteilyn vaaka- ja pystypolarisoitujen komponenttien erotuksen ja summan suhdetta kutsutaan lineaariseksi polarisaatiosuhteeksi. Polarisaatiosuhde voi paljastaa tutkijalle jotain kohteen pinnan ominaisuuksista, kuten pinnan materiaalikoostumuksesta, pakkaustiheydestä ja karheudesta. Lineaariselle polarisaatiosuhteelle on kehitetty joitain malleja joita voidaan sovittaa vaihekulman funktiona havaitulle polarisaatiolle. Nämä mallit ovat perustaltaan kokeellisia eivätkä perustu varsinaisen fysiikan mallintamiseen polarisaatiotapahtumassa. Mallien sovitteet ovat kuitenkin hyödyllisiä kun halutaan verrata eri kohteiden polarisaatio-ominaisuuksia usein varsin harvan ja rajoittuneen havaintoaineiston pohjalta. Mallien sovituksessa käytetään epälineaarista regressioanalyysia sekä bayesilaista epälineaarista regressiota. Bayesin menetelmässä voidaan hyödyntää etukäteistietoa polarisaatiokäyrän käyttäytymisestä jotta sovituksesta saataisiin vakaa myös tapauksissa joissa havaintojen lukumäärä on pieni tai aineisto on muuten puutteellinen. Polarisaatiota tarkastellaan työssä myös valon aallonpituuden funktiona jolloin kiinnostuksen kohteena on aallonpituuden vaikutus polarisaation ominaisuuksiin. Näiden vaikutusten mallintaminen luotettavalla tavalla vaatii mallin ja sovitusmenetelmän huolellista valintaa. Tässä yhteydessä käsitellään mahdollisuutta käyttää usean vasteen regressioanalyysia sekä hierarkkista bayesilaista regressioanalyysia mallin sovituksessa. Työssä esitellään ja vertaillaan malleja ja sovitusmenetelmiä polarisaatiohavaintojen tutkimiseen sekä johdetaan joitain tuloksia aallonpituuden vaikutuksesta polarisaatioon.