Recent Submissions

  • Honkonen, Olga (Helsingin yliopisto, 2015)
    Urbanization is progressing worldwide, with approximately 50% of the Earth s population currently living in urban areas, and this number is expected to increase to 60% by 2025. In Finland, as well as anywhere else, the population is gathered in the cities. At the moment, over 80% of Finns are living in urban areas. Urban areas are also known to produce a significant load of various pollutants to the surrounding environment. One of the significant forms of urban-derived pollutants emission to the surrounding environment is surface runoff. Pollution in urban surface runoff often comes from non-point sources, including motor vehicle emissions, coal and wood burning, tire wear, coal tar, creosote and asphalt leaching, oil spills, and runoff from building sites and other surfaces Our research was focused on distribution and toxicity of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and oil hydrocarbons. Previous studies in other countries indicated that above mentioned pollutants are often present in sediments adjacent to urban areas, may be toxic to aquatic life and recognized as priority pollutants for stormwater. In our study, notable amounts of hydrophobic organic compounds were found in the Lake Vesijärvi sediments and water column as well is in stormwater, urban air and runoff sediment from stormwater traps. Contaminant concentrations in the lake tended to decline with the distance from the urban shore. Toxicity of the sediments, determined with luminescent bacteria test was found to be lower in the Lake Vesijärvi than in the stormwater wells, however no clear gradient with the distance from the urban shore was found. In urban area degree of contamination and toxicity of the sediments depended on traffic intensity in the area. Toxicity of the both lake and stormwater well sediments was also found to correlate partly with organic contaminant content of the samples. These findings suggest that runoff from Lahti urban area has a notable impact on the Lake Vesijärvi condition. Comparison with Finnish contaminated soil guideline values displayed that present contaminant concentrations might be harmful for the natural ecosystem. It indicates that hydrophobic organic pollutants are important contributors to the Lake Vesijärvi sediment contamination and their inputs should be regularly monitored in order to avoid possible decline in the lake sediment quality.
  • Savolainen, Mari (Helsingin yliopisto, 2015)
    Parkinson's disease (PD) is characterized by a slow and gradual loss of neurons and subsequent loss of neurotransmitter dopamine in the movement-related nigrostriatal brain tracts. This causes symptoms of PD, which are resting tremor, rigidity and slowness of movement. Genetic and environmental factors are linked to PD, but its etiology is still largely unknown. Current drug therapies can only relieve the symptoms of PD but treatment to stop or delay the disease progression does not exist at the moment. The main findings in neuropathological characterization of the brain regions that are influenced in PD, are abnormal intraneuronal protein inclusions, called Lewy bodies. Insoluble, aggregated α-synuclein (aSyn) protein is the most abundant component of Lewy bodies. Pathological aggregation and accumulation of aSyn is associated with neuronal death in PD. Therefore, approaches to target aSyn as a potential disease-modifying treatment for PD have been under investigation. The aim of this study was to examine the role of prolyl oligopeptidase (PREP) and pharmacological inhibition of its enzymatic activity by KYP-2047 in aSyn aggregation. Using purified proteins and cell culture model, we showed that PREP forms direct protein-protein interaction with aSyn, thus enhancing its aggregation. KYP-2047 reduced the PREP-mediated aSyn aggregation in cell culture. Then the effects of PREP inhibition on aSyn aggregation were examined in vivo. The purpose was to first characterize a genetic mouse model, carrying mouse A30P mutated aSyn, which is linked to early-onset PD in humans, in order to find out if the mutated mouse aSyn is more prone to aggregate; and to cause PD-like phenotype. The effects of KYP-2047 treatments were assessed in the model. The main findings were that the A30P mutation in mouse aSyn protein caused minor hyperactive behaviour but did not change the brain dopamine levels, and A30P aSyn accumulated in the brain more than wildtype aSyn by age. KYP-2047 treatment reduced the amount of A30P aSyn in immunohistochemical analysis, and the reduction was more specific for high-molecular weight aSyn oligomers in Western blot analysis. We also observed increased autophagy markers in brain tissue. Therefore, PREP inhibition was further studied in cell culture, where it was shown to enhance macroautophagic protein clearance pathway, which is an important pathway in the degradation of high-molecular weight aSyn forms. In the last study, the effects of KYP-2047 were examined in a mouse model of PD that was based on lactacystin-induced inhibition of ubiquitin-proteasome protein degradation pathway. Proteasome inhibition was shown to induce rapid PD-like neurodegeneration recapitulating the cardinal features of PD. KYP-2047 treatment partially protected dopaminergic neurons in the brain and had beneficial effect on motor behaviour, but did not have an effect on aSyn amount. Taken together, this study has provided new insights into the role of PREP in aSyn aggregation and suggest that PREP inhibition has beneficial effects on reducing the aggregation process via two mechanisms. PREP inhibition could be promising and further assessed in the treatment of PD, other α-synucleinopathies and possibly other protein accumulation diseases.
  • Juurikkala, Oskari (Helsingin yliopisto, 2015)
    The study investigates the legal and regulatory aspects of credit default swaps (CDSs), a controversial financial transaction that functions as a type of credit risk insurance. Regarding their legal characterization, it is found that CDSs should normally be classified as insurance contracts unless such classification has been specifically excluded by legislation. It is incorrect to treat them as financial securities, because CDSs are strictly bilateral contracts that can be traded in secondary markets only improperly through novations. Despite their name, their classification as swaps does not correspond to the standard financial meaning of swaps. Recent legislation has broadened the category of swaps to include these transactions in some cases, but the outcome is even more confusing in terms of legal doctrine. Regarding regulatory policy, it is found that the problems created by CDSs should be tackled by a combination of regulatory strategies. At present, the principal regulatory framework is the industry self-governance architecture designed and controlled by the International Swaps and Derivatives Association (ISDA); despite its many weaknesses it also has advantages, which might be harnessed through co-regulation. In terms of transparency regulation, the post-crisis regulatory reforms have moderately reduced the opacity of the CDS market, and increased disclosures would probably fail to address the main problems associated with CDSs. Compulsory central counterparty (CCP) clearing has acquired prominence through the post-crisis regulatory reforms; it is however unlikely to work well for CDSs, which are functionally not swaps but credit insurance, so that their risk profile is asymmetric and involves significant fat tails and macroeconomic correlation. In the future, the most promising alternative is to apply the principles of credit insurance regulation in a way that addresses the peculiar concerns raised by CDSs. Targeted protection selling limits might be applied within the post-reform regulatory scheme that covers CCPs and compulsory collateral requirements. Targeted protection buying regulation is also an option, and the recent European short selling regulation provides a useful test case that will be studied empirically in order to evaluate its effectiveness and costs.
  • Avchaciov, Konstantin (2015)
    Rapid technological development motivates the research community to find out new processing technologies for producing materials with unique properties. Production of new materials or improving the existing ones requires development of new methods, which sometimes involves processing under far-from-equilibrium conditions. Usually underlying physical processes, taking place during such processing, are not well known. Understanding them is the key to the enhancement of processing methods. This thesis covers only a tiny part of a huge number of problems existing in the material science. The studies done here could be useful for solving the problem of metallic glass brittleness and for further development of the ion beam technology for controlling magnetic properties of thin films. Discussion on the pathway of the self-propagating high-temperature synthesis in multilayer metallic films was also included in the thesis We studied the effect of ion irradiation on Cu64Zr36 metallic glass by means of molecular dynamics (MD). Low-energy ion irradiation of metallic glass produces damage zones, where the local structure of glass differs from the structure of pristine glass. These changes are independent on ion energy and flux due to the possibility of partial recovery during cascade relaxation. However, the size of the damage zones could be controlled by varying the dose of ions. This makes possible the production of either isolated damaged regions or homogeneously damaged glass. We showed that mechanical properties of the glass strongly depend on the local structure. In damage zones, the specific arrangement of the structural units is destroyed. This promotes the formation of many shear transformation zones in the damaged area, when a mechanical load is applied. It results in enhanced plasticity of the irradiated glass. Our research indicates that ion irradiation could be used for the softening of brittle metallic glasses for preventing formation of cracks in them. Atomistic studies of the reaction pathway in the multilayer Ru/Al films were done to interpret the results from X-ray diffraction measurements. The MD simulations covered the first nanoseconds; at this timescale, no information about the reaction pathway could be obtained from the experimental methods. The MD simulations demonstrated simultaneous Ru dissolution into liquid Al and $B2$ RuAl phase nucleation at the Ru/Al interface. Our results agreed well with experimental observations, and, moreover, helped to refine understanding of the X-Ray diffractograms. We also studied structural modifications of Pt/Co/Pt trilayer films, which could explain appearance of the perpendicular magnetic anisotropy (PMA) after irradiation with Ga+ ions. Molecular dynamics and Monte Carlo (MD-MC) simulations were performed to find changes in the long range order and short range order, associated with ion irradiation. The results of our simulations showed that the separated metal layers containing Pt and Co were intermixed and formed the new solid solution. This solution was chemically disordered at the nanosecond time scale. With combined MD-MC simulations, we showed that the transition between chemically ordered and disordered phases was possible. The fractions of the ordered phases grew monotonously with an ion dose due to the ongoing process of ion-beam mixing. However, assuming the correlation between the magnetic properties of the film and the fraction of the chemically ordered CoPt phase in it, this result cannot explain the disappearance of PMA at the high doses. The strain analysis showed that the Co layer exhibited tensile strain in the lateral direction at the moderate doses, where the PMA was detected. We explained the appearance of strains by changing of the thickness of the hcp-Co layer right inside the trilayer Pt/Co/Pt structure, which was possible due to its partial transformation to the fcc structure. Below the critical size of the hcp layer, the strain inside it appears, which, in our opinion, could cause the appearance of PMA at the moderate doses and the disappearance of PMA at the high doses.
  • Oksanen, Tuomas (Suomen Ensihoidon Tiedotus Oy, 2015)
    Aims of the study Intensive care is usually necessary for the good survival of postresuscitation patients. The use of some intensive care methods can make the survival better. The main focus of this thesis was to analyze implementation of therapeutic hypothermia in Finnish intensive care units (ICU) and its impact on survival, impact of strict glucose control on the survival of postresuscitation patients, incidence of postresuscitation myocardial depression during therapeutic hypothermia and usefulness of serum NSE concentration for prognostication. Patients and methods Implementation of therapeutic hypothermia and survival of postresuscitation patients in ICUs in Finland was analyzed retrospectively using data from the Finnish Intensive Care Consortium quality database. Impact of glucose control on survival of postresuscitation patients was studied in a randomized controlled study of patients treated with therapeutic hypothermia (24 hours at 33°C) in HUCH ICUs (n = 90). The study patients were randomized to strict (4 6 mmol/l) or moderate (6 8 mmol/l) glucose control for the first 48 hours. The incidence of myocardial depression was studied in a retrospective analysis of hemodynamic data from clinical information system database of 120 postresuscitation patients treated with therapeutic hypothermia (24 hours at 33°C) in HUCH ICUs. Usefulness of serum NSE and some other factors as prognostic tools were analyzed retrospectively from laboratory database of 90 postresuscitation patients treated with ­therapeutic hypothermia (24 hours at 33°C) in HUCH ICUs. Results Therapeutic hypothermia was implemented widely in Finnish ICUs in a few years after international guidelines were published in 2003. In the same time, mortality of postresuscitation patients treated in ICUs decreased. Mortality or serum NSE concentration did not differ between patients treated with strict or moderate glucose control. However, strict glucose control increased risk of hypoglycemia. Myocardial depression, manifesting as low cardiac output (CI less than 1.5 l/min/m2), was ­observed during the first 12 hours in two thirds of patients monitored with pulmonary artery catheter. Other hemodynamic parametres did not differ. Serum NSE concentration at 48 hours after cardiac arrest and decreasing concentration at that time point correlated with neurologic outcome, but with 100% specificity, sensitivity was low. Conclusions Therapeutic hypothermia was implemented rapidly in Finnish ICUs, compared with other European countries or USA. This was associated with better outcome, but causality is uncertain. Strict normoglycemia during intensive care of postresuscitation patients is not necessary. The optimal goal for blood glucose level is not known. Myocardial depression manifesting as low cardiac output is common in postresuscitation patients, but difficult to detect without monitoring cardiac output. The impact of ­recognition and treatment of myocardial depression on outcome requires further studies. Serum NSE measured at least 48 hours after resuscitation can be used as a prognostic tool together with other methods.
  • Lahtinen, Susanna (Helsingin yliopisto, 2015)
    The study is concerned with the interaction between Robert Boyle s experimentalism and medicine. Boyle made an attempt to establish his kind of experimental philosophy as the basis of of medicine. At the same time, however, medicine offered him a model of a discipline which, unlike other learned disciplines, embodied several notions of experiment and ways of writing about experiment. Boyle s involvement in medicine was a complicated exchange of ideas and practices. On the one hand, medical literature and the medical notions of experiment had an impact on his experimental philosophy. On the other hand, however, he also applied his own ideas about experiment and its function to his medical work. In this study, Boyle s medical writings of various kinds, such as recipe books, natural historical works and treatises discussing medical practice, theory and medical reform are explored. I examine these works to find out what kind of activities were called experiment on the one hand, and to explicate the functions of experimental texts in Boyle s medical writings, on the other. To do this, I approach Boyle s medical works from several viewpoints. First of all, I examine Boyle s role as a medical author and place his medical writings in the immediate context formed by contemporary medical literature. Secondly, I explore the different kinds of texts Boyle wrote on the basis of medical experiments and the functions these texts have in his published works. Finally, I examine what these texts tell us about the nature of his experimental activities. My dissertation advances an argument about Boyle s experimentalism and method. I seek to show that contrary to what has often been presumed, Boyle applied no single experimental method in his experimental activities but, instead, that his experimentalism embodied experimental methods of various kinds. His writings do not define experimentalism as a method but rather as a particular kind of approach to natural knowledge. Moreover, the manner in which Boyle s medical works describe his experimental activities shows that there hardly was much method in his manner of working. Hence, this study presents his medical experimentalism as a somewhat disorderly effort and suggests that Boyle s experimental philosophy embodied no single and consistent methodological doctrine.
  • Salmi, Emma (Helsingin yliopisto, 2015)
    Corrosion is a major global challenge with both economical and technological impacts. The total world-wide costs of corrosion have been evaluated to rise to over 2 000 000 million euros annually. While several methods exist for corrosion protection, atomic layer deposited (ALD) coatings have an advantage in applications where thin, fully conformal, highly precise and well-defined coatings both in composition and thickness are needed. In this work the corrosion protection properties of ALD Al2O3 and Ta2O5 based coatings on low alloy steel were studied. The aim was to increase the general understanding on factors affecting the protective properties and failure mechanisms of the ALD coatings. The protective performance of ALD coatings on steel was improved by focusing on three topics: substrate pre-treatment, optimisation of the ALD coating architecture, and combination of the optimised ALD coatings with layers deposited by other methods. The substrate surface was found to significantly influence the ALD coating performance. Improved protective properties were found on steel samples that were mechanically polished to a lower surface roughness, and efficiently cleaned with H2-Ar plasma in addition to the traditional degreasing with an organic solvent. The smoother surface finish was concluded to be beneficial due to decreased defect formation after the coating deposition upon detachment of loose particles or mechanically fragile sites. The H2-Ar plasma removed organic residues from the steel surface, therefore improving the quality of the first layers of the ALD coating. The performance of the ALD coatings themselves was found to improve when Al2O3 and Ta2O5 were combined to produce Al2O3-Ta2O5 nanolaminate and AlxTayOz mixture coatings. In these coatings Al2O3 provided sealing properties and Ta2O5 the chemical stability, therefore resulting in coatings with better long-term performance than could be achieved with either material alone. Optimisation of the Al2O3-Ta2O5 nanolaminate and AlxTayOz mixture coating architectures further enhanced the protective properties. To further improve the coating-steel interface and to widen the application areas for the ALD based protective coatings, the optimised ALD coating processes were combined with layers deposited with other methods. Firstly, thin filtered cathodic arc sublayers were used to separate the ALD process from the steel surface. This enabled a more precise control of the coating-steel interface and led to improved durability of the ALD coatings. Secondly, pinhole defects in physical vapour and plasma-enhanced chemical vapour deposited hard coatings were sealed with ALD to afford coatings with both good corrosion protection performance and resistance against mechanical wear.
  • Rajamäki, Kristiina (Helsingin yliopisto, 2015)
    Atherosclerosis is the underlying cause of myocardial infarction and stroke, the leading causes of death worldwide. It is a complex multifactorial disease closely linked with obesity, type II diabetes, and metabolic syndrome and, together, these conditions comprise the global epidemic of metabolic disorders that are becoming more and more prevalent, affecting adults and children alike. Atherosclerosis affects the large arteries that gradully loose their normal structure and function via a degenerative process involving lipid accumulation and chronic inflammation in the arterial wall. The lipid accumulation is driven by high circulating levels of cholesterol-carrying low density lipoproteins that become trapped and modified in the arterial wall. This causes an inflammatory reaction characterized by abundant immune cell infiltrates, mainly monocyte-derived macrophages. The macrophages scavenge large amounts of lipids and become activated to secrete a host of proinflammatory mediators and matrix-degrading enzymes that drive the progression of the disease. These processes result in the focal development of fatty lesions or plaques along the arteries. Over time, more complex lesions develop as a result of inflammatory and fibrotic responses, matrix remodeling, calcification, cholesterol crystallization, neovessel formation, and microhemorrhages. Ultimately, the plaques may rupture, causing thrombosis and acute complications. Although inflammation is recognized as a major driving force in atherosclerotic lesion development, the mechanisms triggering and maintaining the arterial wall inflammation remain incompletely understood. The aim of this thesis was to study the role of a key innate immune signaling pathway, the inflammasome, in atherosclerosis. The inflammasomes are large cytoplasmic signaling complexes that trigger the proteolytic maturation and secretion of two proinflammatory and proatherogenic cytokines, interleukin(IL)-1beta and -18. The inflammasome pathway can be triggered by microbial components or by sterile endogenous danger signals that elicit the activation of cytoplasmic sensor molecules from the NLR (nucleotide-binding domain and leucine-rich repeat containing) or PYHIN (pyrin and HIN domain containing) families. Despite the established roles of IL-1beta and -18 in driving atherosclerotic lesion development, the triggers of inflammasome activation in atherosclerotic plaques remained unknown. Macrophages are the prototypical inflammasome pathway-expressing cells, and thus cultured human macrophages were utilized to identify and characterize atherosclerosis-associated triggers of the inflammasome pathway. Cholesterol crystals and acidic environment were both found to trigger a strong inflammatory response via the activation of NLRP3 inflammasome and secretion of IL-1beta and IL-18. Cholesterol crystals are a hallmark of atherosclerotic lesions, yet they have been considered an inert material that merely acts as a sink for excess free cholesterol in the arterial wall. These new data suggested, however, that cholesterol crystals act as a potent sterile danger signal that may directly link pathological lipid accumulation and inflammation in the lesions. Local extracellular acidosis arises in the growing plaque due to the hindered diffusion of oxygen and the highly active glycolytic metabolism of macrophages. Acidic environment not only triggered the NLRP3 inflammasome, but even a very mild acidification from the physiological pH of 7.4 to 7.0 was sufficient to greatly amplify the IL-1beta response to other NLRP3 activators, including cholesterol crystals. Having showed that the atherosclerotic lesions harbour potent activators of the inflammasome pathway, we further analyzed the expression of this pathway in atherosclerotic human coronary specimens obtained from 10 explanted hearts. For this purpose, we utilized a quantitative PCR array targeting 88 inflammasome pathway-related molecules. Significant upregulation of 12 target genes was found in advanced coronary plaques compared to early lesions from the same coronary trees, including many of the very core components of the inflammasome pathway. Moreover, p38delta mitogen-activated protein kinase (MAPK), a poorly characterized isoform of the stress- and cytokine-activated p38 MAPK family, was consistently upregulated in advanced coronary plaques. Immunohistochemical stainings of human coronary lesions showed strong expression of NLRP3 inflammasome components and p38delta MAPK in macrophages surrounding the cholesterol crystal-rich lipid core. Furthermore, the p38delta MAPK was activated in cultured human macrophages upon NLRP3 inflammasome activation by cholesterol crystals and extracellular ATP, and required for NLRP3-mediated IL-1beta secretion. Taken together, the data presented in this thesis propose novel inflammasome-mediated mechanisms that may trigger sterile inflammation in atherosclerotic lesions and thus drive lesion progression.
  • Kriikku, Pirkko (Helsingin yliopisto, 2015)
    Driving under the influence of drugs (DUID) can adversely affect driving skills in numerous ways and put lives at risk. Legal approaches to DUID vary considerably from country to country, even within Europe, and, in the last decades the emergence of new psychoactive substances (NPS) has further complicated the scene. DUID is an unlawful act if the substance taken is banned or impairs driving. The latter is hard to define and prove, putting pressure on governments to ban NPS as quickly as possible in order to protect the public by facilitating enforcement of DUID laws. However, banning requires knowledge on several aspects of NPS such as prevalence, pharmacology, abuse potential and toxicity. Up-to-date, evidence-based information on NPS is needed by legislators, toxicologists, clinicians, and other health care professionals. Such information would enable potential drug users and the public to be more aware of the risks associated with illicit use of NPS. This study aimed to add to the knowledge of the NPS most relevant in Finland. In this thesis, the prevalence, blood concentrations in drivers and in post-mortem cases, and demographic details of 3,4-methylenedioxypyrovalerone (MDPV) and desoxypipradrol (2-DPMP), were investigated. Changes in prevalence and other characteristics of MDPV were monitored over a time span covering a period before its banning as well as a few years after banning. Phenazepam, a Russian therapeutic benzodiazepine now illegal in Finland, was studied by examining both DUID and post-mortem cases. The use by apprehended drivers of pregabalin, a prescription anticonvulsant with therapeutic indications for neuropathic pain, partial seizures and generalised anxiety disorder, was also studied. The results of this study showed that DUID cases provide a valuable source of information on NPS prevalence and user profiles. However, little specific information could be gained about the impact on driving performance and health risks of NPS mainly due to the fact that NPS were usually used together with a spectrum of other psychoactive substances. It could, however, be concluded that all of the studied NPS were frequently detected in the samples collected from apprehended drivers and, in the case of MDPV, the prevalence changed with time. The number of MDPV-positive cases among apprehended drivers decreased by 51.1% after the drug was banned. The concentrations of NPS found in DUID cases were within the range anticipated to produce significant adverse effects on driving performance, or, in some cases, in the range found in post-mortem cases where the drug may have contributed to the fatality. The presence of the medicinal drug, pregabalin, was found to be connected to abuse rather than appropriate medical use since it was in most cases found in concentrations higher than those recommended for therapeutic use and together with illegal drugs such as amphetamine or cannabis. In post-mortem cases positive for MDPV, the prevalence of suicide was much greater than in fatalities related to other drugs. Three independent registries, namely the DUID toxicology data, the post-mortem toxicology database, and court documents, were examined to gain novel information on the characteristics of NPS use and those abusing them. The large number of cases studied produced information on concentration ranges associated with abuse of the studied substances.
  • Fabritius, Henna (Helsingin yliopisto, 2015)
    A noticeable fraction of the World s species inhabit disturbed or early-succession habitats. In Finland, 23.3 % of the endangered species are species of traditional agricultural biotopes or otherwise human-modified habitats. These habitats are, after forests, the second most important habitat for endangered species in Finland. When conservation plans have to be designed for early-succession habitats and their species, specific complexities emerge due to their transitional nature. Protected areas are vulnerable to discontinuities in maintenance funding, and alternative strategies for site maintenance vary in terms of maintenance type, intensity and frequency. Besides the establishment of protected areas, species persistence may sometimes be better supported by altering the dynamics of transitional habitats or by establishing new habitat sites. My thesis focuses on the challenges of conservation planning that are related to the maintenance of specific successional stages or disturbance frequencies in dynamically changing environments. My study species is an endangered butterfly, the false heath fritillary (Melitaea diamina), an endangered Finnish butterfly. The false heath fritillary has the status of a species of strict protection in Finland due to the rapid shrinkage of its distribution during the past decades. I have used the false heath fritillary and its habitats as a case study to develop methods to estimate habitat destruction rates, habitat maintenance effects and the spatial emergence pattern of dynamic habitats from field data. We use metapopulation models to study how changes in the patterns of patch emergence and destruction affect population viability and how habitat dynamics affect conservation success. Finally, we contrast our results against the institutional constraints in false heath fritillary conservation. Our results show that false heath fritillary habitats, which occur on multiple land use types, have high destruction rates and reach their best quality 2-3 years since maintenance. In simulations, the habitat turnover rate and the spatio-temporal pattern of habitat patch emergence have a significant effect both on population viability and on the effectiveness of conservation actions. The institutional constraints of false heath fritillary conservation have led to unpredictability in habitat maintenance resourcing. Conservation planning for early-successional species requires monitoring of habitat dynamics and prediction of changes in the future availability of habitat. The availability of site maintenance funding should be taken into account already during the conservation planning phase.
  • Ridderstad, Marianna (Helsingin yliopisto, 2015)
    Studies of ancient monuments and buildings have shown that many of them were astronomically oriented. The examination of the orientations of the structures constructed by past cultures can thus reveal previously unknown details of their astronomical knowledge, calendric practices and religious beliefs. In this thesis, the orientations of two types of structures from prehistoric and early historical Finland were investigated: the Giants Churches (GCs), which are large Neolithic (ca. 1800-3000 BCE) stone enclosures situated mainly on the ancient coast of Ostrobothnia, and the medieval stone churches of Finland (ca. 1300-1550 CE). The results of the studies showed that the axes and gates of the GCs pointed towards the directions of certain solar and lunar events, possibly even indicating the existence of a lunar or lunisolar seasonal pointer calendric system of the type that has been previously suggested for European Neolithic monuments. The small GCs were oriented differently from the large ones, and especially the very largest GCs had orientations towards some of the main solar events of the year. The studies also revealed that the GCs were positioned to face open views towards the eastern and south-eastern horizon, and that the cairns around them were often symmetrically placed with respect to each other and the enclosures of the GCs. The orientations of the stone churches were found to have been mainly towards the sunrises of the equinoxes as given by the various possible definitions of the equinox in medieval times. Part of the orientation distribution could also be related to the sunrises of the Easter Day, and some individual churches may have been targeted towards the sunrises of the feast days of their patron saints. Comparison of the monument orientations from the two very different periods of time and cultures, the Neolithic GC culture and the medieval Finland showed that while there were many similarities in the orientations themselves, the interpretations made of the orientations and their possible related belief systems necessarily have differences. Also, the uncertainties in the interpretations of the orientations of a distant illiterate culture, in this case the Neolithic GC culture, persist. The concrete use of pre-Christian myths in rituals at the time when the medieval Christian churches were at use illustrates the complexity of the situation of the vernacular religion in Finland in historical times. This complexity naturally has an effect on the interpretations made on how the medieval Finnish parish members may have interpreted the observed orientations of the stone churches. Thus, also the interpretations made of the meanings of the orientations in a literate culture relatively close in time, where one has written sources preserved, may bear uncertainties due to the complex situation of the vernacular religious practices and beliefs. The complexity of the religious situation and the related interpretations of the church orientations in medieval Finland indicate the existence of limitations on how the orientations of the Neolithic structures, which are much more distant in time and culture, can and should be interpreted.
  • Pöyhönen, Päivi (Helsingin yliopisto, 2015)
    The proportion of the Finnish population approaching old age is increasing rapidly. This challenges Finnish society and increases the need for elderly care services. Individuals responsibility for themselves and their elderly family members is growing, while the welfare society is undergoing reformation. In Finland, elderly care involves both municipal workers and actors such as companies, organisations and religious communities. In Finland, the Evangelical Lutheran Church (ELCF) and its parishes can be positioned between the public and third sectors. The Church organises its elderly care as part of diaconal and common parish work. The ELCF has adjusted this care based on societal change. For example, after the economic recession of the 1990s, the ELCF reallocated its resources from elderly care to financial assistance for people of working age. The ELCF employs a holistic concept of people in its diaconal work: it considers their spiritual or religious needs. Such needs are often accentuated among the elderly. This study explores the role of the ELCF in the field of elderly care in Finland. The dissertation consists of four articles in which the ELCF s role is examined through its history, the views of both church diaconal and municipal social workers, and the expectations of ordinary citizens directed to the ELCF for elderly care. This research is qualitative. The research material consists of the four-year reports the Church produced from 1898 to 2007 and two separate sets of interview data. Twenty-five ordinary Finns were interviewed in 2007 and twenty-two diaconal and social workers in 2009. The data were evaluated by using inductive content or abductive frame analysis, as appropriate. The study shows that the ELCF plays an important but complex role in elderly care. Both citizens and social workers expect the Church to fill a role previously associated with the public sector. In addition to the spiritual or religious needs of the elderly, psychosocial support is also provided by the ELCF. These expectations are motivated by both the neutrality demanded of social workers and various restrictions on their resources and expertise. Diaconal work proved to be employee centred, and in elderly care, strategies often failed in practice. For the ELCF, the most important cooperation is with the public sector. The results, however, show signs of asymmetrical power relations between the social and diaconal workers. This also became clear through contractuality, which will be used more in the future in organising cooperation. The responsibilities and tasks involved in elderly care are being redefined. This not only affects solidarity, the key concept behind the current welfare model, but also changes it. Reaffirming the concept of social solidarity among individuals can be seen as a task more and more appropriate for the ELCF s elderly care efforts. This kind of solidarity is needed to strengthen individual responsibility in caring for the elderly population.
  • Vehkanen, Marjut (Helsingin yliopisto, 2015)
    From grammar to communication: Finnish as a second and foreign language textbooks from 1866 to 1953. Marjut Vehkanen, University of Helsinki, Finland The primary sources of this study include Finnish as a second and foreign language textbooks that were published between 1866 and 1953. The corpus for the study consists of 52 Finnish as a second and foreign language textbooks targeted both at children and adult learners. The analysis focuses on the following domains: the presentation of grammar, text types, content topics and pedagogical methods. Methodologically, this study is based on close reading and content analysis of the chosen textbooks. The research questions of this dissertation are the following: - Who were the authors and the intended audience of the textbooks analysed in this dissertation, and where were these textbooks studied? - What is the role of grammar in the textbooks? How has the presentation of grammatical phenomena changed during the research period? - How are different text types used in the analysed textbooks? - What changes in the world are seen in the textual contents? - How is the development of language teaching methods reflected in the textbooks during the researched period? The study shows that the teaching of grammar occupied a very central position from 1866 to 1953; even most of the practically oriented textbooks included grammar sections. Significant differences emerged when comparing the text types among the adult textbooks. For example, the analysed corpus includes a Finnish phrasebook with phrases intended to be learnt by heart. Whereas some types of text were discontinued after the first part of the period, new types emerged, but some permanent text types were found in the books during the entire period. The study reveals how the books for adult learners offered a diverse and rich range of themes and pedagogical methods and how little the contents of the schoolbooks changed. The results of this study introduce many linguistic and historical themes for further research. For example, one topic for further study is how past authors of textbooks have approached the Finnish cases or the extent to which they have focused on combining the teaching of vocabulary and grammar in their textbooks. In addition, no research has yet been conducted to survey the pedagogical history of Finnish as a second and foreign language textbooks.
  • Laurila (os. Heikkilä), Henna (Helsingin yliopisto, 2015)
    Canine idiopathic pulmonary fibrosis (CIPF) is a chronic interstitial lung disease of unknown origin mainly affecting West Highland white terriers (WHWT). No curative treatment exists. Differentiating CIPF from other chronic respiratory diseases is difficult. Therefore, a measurable biomarker would be helpful. CIPF shares clinical features with human idiopathic pulmonary fibrosis (IPF), but the histopathological resemblance of the two diseases has been unclear. We described the clinicopathological and diagnostic imaging findings in dogs with CIPF and compared them with those of healthy WHWTs. The most typical clinical signs were cough and exercise intolerance. Inspiratory Velcro crackles were characteristic and an abdominal breathing pattern was often present. Many dogs were hypoxemic. Bronchointerstitial opacity was the most common radiographic finding. In high resolution computed tomography, ground glass opacity was a consistent feature, whereas honeycombing and traction bronchiectasis were less common. Bronchoalveolar lavage fluid (BALF) total cell count was elevated in CIPF and bronchial changes were common. We investigated the serum and BALF concentrations of two potential fibrosis biomarkers, endothelin-1 (ET-1) and procollagen type III amino terminal propeptide (PIIINP) in dogs with CIPF, chronic bronchitis (CB), eosinophilic bronchopneumopathy (EBP) and healthy dogs. Serum ET-1 was higher in dogs with CIPF than in other groups. BALF ET-1 was measurable only in dogs with CIPF. BALF PIIINP was higher in dogs with CIPF than in dogs with CB or healthy dogs, but not different from dogs with EBP. Serum PIIINP was not useful. We defined the histopathological lesions and their distribution in WHWTs with CIPF and compared them with those of human usual interstitial pneumonia (UIP), which is the histopathological pattern of human IPF, and human nonspecific interstitial pneumonia (NSIP), which is an important differential diagnosis of human IPF. A diffuse mature interstitial fibrosis of varying severity, resembling human NSIP, was seen in the lungs of all CIPF dogs. The majority of CIPF dogs also had multifocal areas of accentuated subpleural and peribronchiolar fibrosis with occasional honeycombing and profound alveolar epithelial changes, reminiscent of human UIP. Interstitial fibroblastic foci, characteristic of UIP, were not seen in WHWTs. In this thesis we provide a detailed description of the clinicopathologic and diagnostic imaging features of CIPF and present quantitative values for arterial blood gases and BALF cytology. Serum ET-1 and BALF PIIINP are elevated in dogs with CIPF and could differentiate CIPF from CB. Histopathologically, CIPF is characterised by two types of interstitial fibrosis and shares features of both human UIP and NSIP.
  • Llano, Olaya (Helsingin yliopisto, 2015)
    Dendritic spines are the main site of reception of glutamatergic -excitatory- neurotransmission in the central nervous system. According to the current view on neuronal function, dendritic spines play a pivotal role in the formation of synaptic networks for memory storage. Consequently, dendritic spines are crucial for cognitive processes, e.g. learning. Numerous disorders such as intellectual developmental disorders, schizophrenia and cognitive impairment are associated with functional and structural abnormalities of dendritic spines. The main objectives of this project were to identify molecular regulators of the structure and function of dendritic spines and to characterise novel mechanisms leading to dendritic spine development and synapse formation. Actin is the most abundant protein in dendritic spines. Rearrangements of the actin cytoskeleton are responsible for the morphological changes of dendritic spines, making actin a major player in the regulation of glutamatergic synaptogenesis. Increasing evidence shows that dendritic filopodia are crucial in the formation of dendritic spines. Often filopodia act as precursors of mature dendritic spines. While filopodial protrusions in other cell types have been widely studied, the molecular mechanisms regulating the emergence and maintenance of dendritic filopodia are poorly understood. In this thesis work, we show that the polymerizing factor mDia2 promotes initiation and polymerization of actin in the filopodial tip. We also describe a novel observation of filopodial root polymerization. Spine maturation is accompanied by expansion of the spine head. We propose here that the actin polymerizing factor Arp2/3 complex takes active part in the branched actin polymerization during spine head expansion. Spine heads are dynamic structures, with long protrusions often visible on their surface. Our results demonstrate that the actin depolymerizing factor cofilin-1 has a double function in the regulation of dendritic spine actin dynamics. On one hand cofilin-1 replenishes the actin monomer pool, and on the other hand it shapes the spines by severing the actin filaments and therefore controls actin filament length. The maturation of synaptic networks is strictly dependent on the synchronous development of both inhibitory and excitatory transmission. Within this context the formation of and stabilization of dendritic spines is an important step in the maturation of glutamatergic transmission. However, in terms of functional maturation, chloride regulatory proteins, such as the K-Cl cotransporter KCC2, are crucial regulators of GABAergic -inhibitory- transmission. Interestingly, previous studies have identified KCC2 as an important agent required for the maturation of dendritic spines and consequently glutamatergic transmission. The mechanism how KCC2 exerts its chloride-extrusion independent effect on dendritic spines and excitatory synapses remained obscure. In this thesis work we have identified the molecular interaction between the potassium-chloride cotransporter KCC2 and the guanine nucleotide exchange factor βPix. Importantly, KCC2 inhibits the action of βPix towards the GTPase Rac1, a major regulator of the actin cytoskeleton in dendritic spines. The inhibition of βPix by KCC2 leads to decreased cofilin-1 inactivation and subsequent reduction in the fraction of actin that is stable. This novel molecular pathway leads to the regulation of glutamatergic synaptogenesis and spine formation by KCC2 via βPix. Synaptic cell adhesion molecules orchestrate trans-synaptic recognition as well as specification of glutamatergic synapses. Fine-tuning of synaptic networks requires a delicate balance between positive and negative signalling mechanisms that regulate dendritic spine formation. The intercellular adhesion molecule ICAM-5 negatively regulates the maturation of dendritic spines. We have found that ICAM-5 binds to pre-synaptic β1 integrins in filopodia and immature dendritic spines, preventing spine maturation. We have characterized the molecular mechanisms leading to the diminished interaction of ICAM-5 and β1 integrins during spine maturation. Moreover, genetic manipulation of ICAM5 affected the morphology and function of dendritic spines. The results included in this thesis work contribute to the deeper understanding of the molecular mechanisms regulating the development of dendritic spines. We have studied molecules that control all steps of these processes, from filopodia formation to mature spine regulation; encompassing structural and functional synaptogenesis.