51 resultados para forced migrants

em Helda - Digital Repository of University of Helsinki


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Activation of midbrain dopamine systems is thought to be critically involved in the addictive properties of abused substances. Drugs of abuse increase dopamine release in the nucleus accumbens and dorsal striatum, which are the target areas of mesolimbic and nigrostriatal dopamine pathways, respectively. Dopamine release in the nucleus accumbens is thought to mediate the attribution of incentive salience to rewards, and dorsal striatal dopamine release is involved in habit formation. In addition, changes in the function of prefrontal cortex (PFC), the target area of mesocortical dopamine pathway, may skew information processing and memory formation such that the addict pays an abnormal amount of attention to drug-related cues. In this study, we wanted to explore how long-term forced oral nicotine exposure or the lack of catechol-O-methyltransferase (COMT), one of the dopamine metabolizing enzymes, would affect the functioning of these pathways. We also wanted to find out how the forced nicotine exposure or the lack of COMT would affect the consumption of nicotine, alcohol, or cocaine. First, we studied the effect of forced chronic nicotine exposure on the sensitivity of dopamine D2-like autoreceptors in microdialysis and locomotor activity experiments. We found that the sensitivity of these receptors was unchanged after forced oral nicotine exposure, although an increase in the sensitivity was observed in mice treated with intermittent nicotine injections twice daily for 10 days. Thus, the effect of nicotine treatment on dopamine autoreceptor sensitivity depends on the route, frequency, and time course of drug administration. Second, we investigated whether the forced oral nicotine exposure would affect the reinforcing properties of nicotine injections. The chronic nicotine exposure did not significantly affect the development of conditioned place preference to nicotine. In the intravenous self-administration paradigm, however, the nicotine-exposed animals self-administered nicotine at a lower unit dose than the control animals, indicating that their sensitivity to the reinforcing effects of nicotine was enhanced. Next, we wanted to study whether the Comt gene knock-out animals would be a suitable model to study alcohol and cocaine consumption or addiction. Although previous work had shown male Comt knock-out mice to be less sensitive to the locomotor-activating effects of cocaine, the present study found that the lack of COMT did not affect the consumption of cocaine solutions or the development of cocaine-induced place preference. However, the present work did find that male Comt knock-out mice, but not female knock-out mice, consumed ethanol more avidly than their wild-type littermates. This finding suggests that COMT may be one of the factors, albeit not a primary one, contributing to the risk of alcoholism. Last, we explored the effect of COMT deficiency on dorsal striatal, accumbal, and prefrontal cortical dopamine metabolism under no-net-flux conditions and under levodopa load in freely-moving mice. The lack of COMT did not affect the extracellular dopamine concentrations under baseline conditions in any of the brain areas studied. In the prefrontal cortex, the dopamine levels remained high for a prolonged time after levodopa treatment in male, but not female, Comt knock-out mice. COMT deficiency induced accumulation of 3,4-dihydroxyphenylacetic acid, which increased further under levodopa load. Homovanillic acid was not detectable in Comt knock-out animals either under baseline conditions or after levodopa treatment. Taken together, the present results show that although forced chronic oral nicotine exposure affects the reinforcing properties of self-administered nicotine, it is not an addiction model itself. COMT seems to play a minor role in dopamine metabolism and in the development of addiction under baseline conditions, indicating that dopamine function in the brain is well-protected from perturbation. However, the role of COMT becomes more important when the dopaminergic system is challenged, such as by pharmacological manipulation.

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Regional autonomy in Indonesia was initially introduced as a means of pacifying regional disappointment at the central government. Not only did the Regional Autonomy Law of 1999 give the Balinese a chance to express grievance regarding the centralist policies of the Jakarta government but also provided an opportunity to return to the regional, exclusive, traditional village governance (desa adat). As a result, the problems faced by the island, particularly ethnic conflicts, are increasingly handled by the mechanism of this traditional type of governance. Traditional village governance with regard to ethnic conflicts (occurring) between Balinese and migrants has never been systematically analyzed. Existing analyses emphasized only the social context, but do not explain either the cause of conflicts and the ensuing problems entails or the virtues of traditional village governance mechanisms for mediating in the conflict. While some accounts provide snapshots, they lack both theoretical and conflict study perspective. The primary aim of this dissertation is to explore the expression and the causes of conflict between the Balinese and migrants and to advance the potential of traditional village governance as a means of conflict resolution with particular reference to the municipality of Denpasar. One conclusion of the study is that the conflict between the Balinese and migrants has been expressed on the level of situation/contradiction, attitudes, and behavior. Yet the driving forces behind the conflict itself consist of the following factors: absence of cooperation; incompatible position and perception; inability to communicate effectively; and problem of inequality and injustice, which comes to the surface as a social, cultural, and economic problem. This complex of factors fuels collective fear for the future of both groups. The study concludes that traditional village governance mechanisms as a means of conflict resolution have not yet been able to provide an enduring resolution for the conflict. Analysis shows that the practice of traditional village governance is unable to provide satisfactory mechanisms for the conflict as prescribed by conflict resolution theory. Traditional village governance, which is derived from the exclusive Hindu-Balinese culture, is accepted as more legitimate among the Balinese than the official governance policies. However, it is not generally accepted by most of the Muslim migrants. In addition, traditional village governance lacks access to economic instruments, which weakens its capacity to tackle the economic roots of the conflict. Thus the traditional mechanisms of migrant ordinance , as practiced by the traditional village governance have not yet been successful in penetrating all aspects of the conflict. Finally, one of the main challenges for traditional village governance s legal development is the creation of a regional legal system capable of accommodating rapid changes in line with the national and international legal practices. The framing of the new laws should be responsive to the aspirations of a changing society. It should not only protect the various Balinese communities interests, but also that of other ethnic groups, especially those of the minority. In other words, the main challenge to traditional village governance is its ability to develop flexibility and inclusiveness.

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Spirometry is the most widely used lung function test in the world. It is fundamental in diagnostic and functional evaluation of various pulmonary diseases. In the studies described in this thesis, the spirometric assessment of reversibility of bronchial obstruction, its determinants, and variation features are described in a general population sample from Helsinki, Finland. This study is a part of the FinEsS study, which is a collaborative study of clinical epidemiology of respiratory health between Finland (Fin), Estonia (Es), and Sweden (S). Asthma and chronic obstructive pulmonary disease (COPD) constitute the two major obstructive airways diseases. The prevalence of asthma has increased, with around 6% of the population in Helsinki reporting physician-diagnosed asthma. The main cause of COPD is smoking with changes in smoking habits in the population affecting its prevalence with a delay. Whereas airway obstruction in asthma is by definition reversible, COPD is characterized by fixed obstruction. Cough and sputum production, the first symptoms of COPD, are often misinterpreted for smokers cough and not recognized as first signs of a chronic illness. Therefore COPD is widely underdiagnosed. More extensive use of spirometry in primary care is advocated to focus smoking cessation interventions on populations at risk. The use of forced expiratory volume in six seconds (FEV6) instead of forced vital capacity (FVC) has been suggested to enable office spirometry to be used in earlier detection of airflow limitation. Despite being a widely accepted standard method of assessment of lung function, the methodology and interpretation of spirometry are constantly developing. In 2005, the ATS/ERS Task Force issued a joint statement which endorsed the 12% and 200 ml thresholds for significant change in forced expiratory volume in one second (FEV1) or FVC during bronchodilation testing, but included the notion that in cases where only FVC improves it should be verified that this is not caused by a longer exhalation time in post-bronchodilator spirometry. This elicited new interest in the assessment of forced expiratory time (FET), a spirometric variable not usually reported or used in assessment. In this population sample, we examined FET and found it to be on average 10.7 (SD 4.3) s and to increase with ageing and airflow limitation in spirometry. The intrasession repeatability of FET was the poorest of the spirometric variables assessed. Based on the intrasession repeatability, a limit for significant change of 3 s was suggested for FET during bronchodilation testing. FEV6 was found to perform equally well as FVC in the population and in a subgroup of subjects with airways obstruction. In the bronchodilation test, decreases were frequently observed in FEV1 and particularly in FVC. The limit of significant increase based on the 95th percentile of the population sample was 9% for FEV1 and 6% for FEV6 and FVC; these are slightly lower than the current limits for single bronchodilation tests (ATS/ERS guidelines). FEV6 was proven as a valid alternative to FVC also in the bronchodilation test and would remove the need to control duration of exhalation during the spirometric bronchodilation test.

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The aim of this thesis is to examine the skilled migrants’ satisfaction with the Helsinki Metropolitan Area. The examination is executed on three scales: housing, neighbourhoods and the city region. Specific focus is on the built environment and how it meets the needs of the migrants. The empirical data is formed of 25 semi-structured interviews with skilled migrants and additionally 5 expert interviews. Skilled and educated workforce is an increasingly important resource in the new economy, and cities are competing globally for talented workers. With aging population and a need to develop its innovational structure, the Helsinki Metropolitan Area needs migrant workforce. It has been stated that quality of place is a central factor for skilled migrants when choosing where to settle, and from this perspective their satisfaction with the region is significant. In housing, the skilled migrants found the price-quality ratio and the general sizes of apartments inadequate. The housing market is difficult for the migrants to approach, since they often do not speak Finnish and there are prejudices towards foreigners. The general quality of housing was rated well. On the neighbourhood level, the skilled migrants had settled in residential areas which are also preferred by the Finnish skilled workers. While the migrants showed suburban orientation in their settlement patterns, they were not concentrated in the suburban areas which host large shares of traditional immigrant groups. Migrants were usually satisfied with their neighbourhoods; however, part of the suburban dwellers were unsatisfied with the services and social life in their neighbourhoods. Considering the level of the city region, the most challenging feature for the skilled migrants was the social life. The migrants felt that the social environment is homogeneous and difficult to approach. The physical environment was generally rated well, the most appreciated features being public transportation, human scale of the Metropolitan Helsinki, cleanliness, and the urban nature. Urban culture and services were seen good for the city region’s size, but lacking in international comparison.

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"We have neither Eternal Friends nor Eternal Enemies. We have only Eternal Interests .Finland's Relations with China 1949-1989 The study focuses on the relations between Finland and the People s Republic of China from 1949-1989 and examines how a small country became embroiled in international politics, and how, at the same time, international politics affected Finnish-Chinese relations and Finland s China policy formulation. The study can be divided into three sections: relations during the early years, 1949-1960, before the Chinese and Soviet rift became public; the relations during the passive period during the 1960s and 1970s; and the impact of China s Open Door policy on Finland s China policy from 1978-1989. The diplomatically challenging events around Tiananmen Square and the reactions which followed in Finland bring the study to a close. Finland was among the first Western countries to recognise the People s Republic and to establish diplomatic relations with her, thereby giving Finland an excellent position from which to further develop good relations. Finland was also the first Western country to sign a trade agreement with China. These two factors meant that Finland was able to enjoy a special status with China during the 1950s. The special status was further strengthened by the systematic support of the government of Finland for China's UN membership. The solid reputation earned in the 1950s had to carry Finland all the way through to the 1980s. For the two decades in between, during the passive policy period of the 1960s and 1970s, relations between Finland and the Soviet Union also determined the state of foreign relations with China. Interestingly, however, it appeared that President Urho Kekkonen was encouraged by Ambassador Joel Toivola to envisage a more proactive policy towards China, but the Cultural Revolution cut short any such plan for nearly twenty years. Because of the Soviet Union, Finland held on to her passive China policy, even though no such message was ever received from the Soviet Union. In fact, closer relationships between Finland and China were encouraged through diplomatic channels. It was not until the presidency of Mauno Koivisto that the first high-level ministerial visit was made to China when, in 1984, Foreign Minister Paavo Väyrynen visited the People s Republic. Finnish-Chinese relations were lifted to a new level. Foreign Minister Väyrynen, however, was forced to remove the prejudices of the Chinese. In 1985, when the Speaker of the Finnish Parliament, Erkki Pystynen visited China he also discovered that Finland s passive China policy had caused misunderstandings amongst the Chinese politicians. The number of exchanges escalated in the wake of the ground-breaking visit by Foreign Minister Väyrynen: Prime Minister Kalevi Sorsa visited China in 1986 and President Koivisto did so in 1988. President Koivisto stuck to practical, China-friendly policies: his correspondence with Li Peng, the attitude taken by the Finnish government after the Tiananmen Square events and the subsequent choices made by his administration all pointed to a new era in relations with China.

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The master's thesis concerns the decisions of the imperial policy-makers in their Danish foreign policy during the crisis that culminated in the dissolution of the Nordic union of Kalmar during the years 1521-24. The sources consist of printed sources that mainly are collections of letters and diplomas, and additionally, acquaintance has been made with studies treating the subject. The aim of the study was to clarify the objectives, means and execution of the imperial policy and what priorizations did they make between the different objectives. Also, the part played by Denmark in the imperial foreign policy in general was to be assessed. Particularly, the aim was to find out and state a hierarchy between the importance of the different objectives by analyzing the choices made. It was observed that the continuing of peaceful relations in the North was clearly preferred in the imperial policy, especially as their war against France drew out. A war was seen as deteriorating the freedom of action of the main ally, king Christian II, and an armed conflict was to be prevented. The conceived impossibilty to intervene with armed forces to Christian's favour forced the imperial side to postpone their objectives in the fields of dynastical and alliance policy. In comparison to these, less weight was given to maintaining the rights and position of the empire and the rights granted in its name. To the Habsburgs, maintaining the economical embargo of Sweden, run forcefully by Christian II, was the least preferred objective. In light of the results of the master's thesis, the conceived priorities of the Northern European policy adopted by the imperial side resembled their political priorities in general.

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In my master thesis I analyse Byzantine warfare in the late period of the empire. I use military operations between Byzantines and crusader Principality of Achaia (1259–83) as a case study. Byzantine strategy was based (in “oriental manner”) on using ambushes, diplomacy, surprise attacks, deception etc. Open field battles that were risky in comparison with their benefits were usually avoided, but the Byzantines were sometimes forced to seek open encounter because their limited ability to keep strong armies in field for long periods of time. Foreign mercenaries had important place in Byzantine armies and they could simply change sides if their paymasters ran out of resources. The use of mercenaries with short contracts made it possible that the composition of an army was flexible but on the other hand heterogeneous – in result Byzantine armies were sometimes ineffective and prone to confusion. In open field battles Byzantines used formation that was made out from several lines placed one after another. This formation was especially suitable for cavalry battles. Byzantines might have also used other kinds of formations. The Byzantines were not considered equal to Latins in close combat. West-Europeans saw mainly horse archers and Latin mercenaries on Byzantine service as threats to themselves in battle. The legitimacy of rulers surrounding the Aegean sea was weak and in many cases political intrigues and personal relationships can have resolved the battles. Especially in sieges the loyalty of population was decisive. In sieges the Byzantines used plenty of siege machines and archers. This made fast conquests possible, but it was expensive. The Byzantines protected their frontiers by building castles. Military operations against the Principality of Achaia were mostly small scale raids following an intensive beginning. Byzantine raids were mostly made by privateers and mountaineers. This does not fit to the traditional picture that warfare belonged to the imperial professional army. It’s unlikely that military operations in war against the Principality of Achaia caused great demographic or economic catastrophe and some regions in the warzone might even have flourished. On the other hand people started to concentrate into villages which (with growing risks for trade) probably caused disturbance in economic development and in result birth rates might have decreased. Both sides of war sought to exchange their prisoners of war. These were treated according to conventional manners that were accepted by both sides. It was possible to sell prisoners, especially women and children, to slavery, but the scale of this trade does not seem to be great in military operations treated in this theses.

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Tutkielma on etnografisella tutkimusotteella toteutettu tapaustutkimus, jossa oli tutkimuskohteena yksi pääkaupunkiseudun peruskoulun neljäs luokka. Tutkimus suoritettiin kevätlukukaudella 1998. Luokalla oli 24 oppilasta, joista kaksi oli somalialaisia muslimityttöjä. Aineistonkeruumenetelmiä olivat osallistuva havainnointi, teemahaastattelut, keskustelut ja luokan oppilaiden kirjoittamat kirjoitelmat. Tutkimustehtävänä oli kuvata ja ymmärtää muslimityttöjen olemassaolon vaikutusta luokan arkipäivään luokan eri osapuolien kannalta. Kiinnostuksen kohteena oli, miten opettaja ja luokan muut oppilaat suhtautuivat muslimityttöihin ja millaisia olivat muslimityttöjen omat kokemukset luokan elämästä ja miten heidän uskontonsa, islam, näkyi koulupäivän aikana. Tutkimustuloksista: Islam näkyi koulupäivän aikana konkreettisimmin muslimityttöjen pukeutumisessa ja ruokailussa. He saivat myös islaminuskon opetusta, harjoittelivat paastoamista paastokuukauden aikana ja heillä oli lupa olla pois koulusta muslimien juhlapyhinä. Luokan muut oppilaat tiesivät, että muslimitytöillä oli eri uskonto kuin heillä, mutta he eivät uskoneet sen vaikuttavan muslimityttöjen koulupäivään kovinkaan paljon. Muslimitytöt olivat solmineet ystävyyssuhteita luokan suomalaisiin tyttöihin ja he viihtyivät hyvin heidän kanssaan. Muslimityttöjä oli kuitenkin kiusattu enemmän kuin luokan muita oppilaita, mutta kiusaaminen oli vähentynyt ajan kuluessa. Muutamilla luokan pojilla oli halveksiva tai vihamielinen suhtautuminen muslimityttöihin. Muslimityttöjen koulunkäyntiin liittyi joitakin vaikeuksia, kuten oppimisvaikeudet muutamissa aineissa ja vaikeudet sopeutua tiettyihin koulun sääntöihin. Luokanopettaja koki yhteistyön muslimityttöjen vanhempien kanssa vaikeaksi. Näistä ongelmista huolimatta muslimitytöillä oli myönteinen suhtautuminen koulunkäyntiin. Tässä tapauksessa muslimitytöt olivat saavuttaneet integraatio-vaiheen Berryn akkulturaatio teorian mukaan. Sopeutuminen peruskoululuokkaan oli onnistunut heiltä hyvin lähinnä luokanopettajan toiminnan johdosta. He puhuivat hyvin suomen kieltä ja olivat asuneet Suomessa jo usean vuoden ajan, mikä myös helpotti sopeutumista. Muslimi, islam, kulttuuri, peruskoulu, maahanmuuttajaopetus, etnografinen tutkimus, tapaustutkimus Muslim, islam, culture, comprehensive school, teaching of migrants, ethnographical research, case study

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Finnish education politics presume that basic education should be equal to all students. While organising craft education equality can be understood as similarity or as possibility to choose. The possibility to be able to choose whether textile or technical craft despite of one´s gender has been the aim of laws and curriculums already over 30 years. In practice it´s almost impossible to students to ignore feminine and masculine roles that go deep into our culture. Choosing craft has been divided by gender, which is the reason why possibility to choose has not been good enough to educationalists of equality. The latest guidelines for the National core curriculum for bacis education were issued in 2004. According to curriculum craft education consists parts of both technical and textile craft. All students should take part in both sectors of crafts. Furthermore, one can be given a possibility to consentrate his studies in whether textile or technical craft. The curriculum does not set the rules how the education should be organised, which means that it can be organised in many ways depending on city, school or teacher. Teachers and other specialists have contradictory feelings towards shared craft education, because traditional way to see craft in Finland is to separate textile craft from technical craft. Both crafts have some common features that are introduced in curriculum. Besides there is many equal things in craft theories that bind textile and technical craft to each other. The main purpose of this research was to find out, how shared craft education has been organised at the 7.th grade in Finnish comprehensive school, and which things affect in the settlements. Second goal was to describe and compare teachers´ experiences in teaching shared craft education. Third aim of this study was how shared craft has changed craft education. I collected the research material in May 2006 by interviewing both textile and technical craft teachers who teach shared craft. The material consists of fourteen theme interviews. In the analysis of the material I used theoretic bounded document analysis. According to the research there are three different ways to organise shared craft education: 50 50-arrangement, exchanging period and project week. In the schools that carried out 50 50-arrangement teaching was realised mainly in heterogenous groups. Principals had usual a lot of authorization on how to arrange craft education, which means that their views on equality, laws and curriculum affected in the settlemets more than teachers´ opinions. Teachers´ attitudes to shared craft were mainly positive. The changing of craft education can be divided in two parts: the aims and the containings of the curriculum have changed, as well as the meaning of the craft as core subject. Teachers have been forced to decrease the containings of both textile and technical crafts. Despite of eliminations both crafts still have comprehensive containings. Teachers decided what to teach by these argumets: Students should learn some basic things or produce a certain product. Usually teachers had also a lot of experience and special intrests in crafts. According to this research there is four significant meanings for shared craft education: 1) developing readiness for doing things, 2) developing skills of thinking, 3) delight of doing things and 4) teaching attitude.

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Paracrine regulation between the components of the tumour microenvironment cancer cells, activated fibroblasts, immune and endothelial cells is under intense investigation. The signals between the different cell types are mediated by soluble factors, such as growth factors, proinflammatory cytokines and proteolytic enzymes. Nemosis is an experimental in vitro model of fibroblast activation, leading to increased production of such mediators. Nemotic activation of fibroblasts occurs as they are forced to cluster thereby forming a multicellular spheroid. The aim of the present studies was to elucidate the mechanisms underlying the nemotic response of cancer-associated fibroblasts (CAF) and the role of nemosis in paracrine regulation between activated fibroblasts and benign and malignant epithelial cells. The results presented in this thesis demonstrate that the nemotic response of CAFs and normal fibroblasts differs, and inter-individual variations exist between fibroblast populations. In co-culture experiments, fibroblasts increased colony formation of squamous cell carcinoma (SCC) cells, and CAFs further augmented this, highlighting the tumour-evolving properties of CAFs. Furthermore, fibroblast monolayers in those co-cultures started to cluster spontaneously. This kind of spontaneous nemosis response might take place also in vivo, although more direct evidence of this still needs to be obtained. The HaCaT skin carcinoma progression model was used to study the effects of benign and malignant keratinocytes on fibroblast nemosis. Benign HaCaT cells inhibited fibroblast nemosis, observed as inhibition of cyclooxygenase 2 (COX-2) induction in nemotic spheroids. In contrast, malignant HaCaTs further augmented the nemotic response by increasing expression of COX-2 and the growth factors hepatocyte growth factor / scatter factor (HGF/SF) and vascular endothelial growth factor (VEGF), as well as causing a myofibroblastic differentiation of nemotic fibroblasts into fibroblasts resembling CAFs. On the other side of this reciprocal signalling, factors secreted into conditioned medium by the nemotic fibroblasts promoted proliferation and motility of the HaCaT cell lines. Notably, the nemotic fibroblast medium increased the expression of p63, a transcription factor linked to carcinogenesis, also in the highly metastatic HaCaT cells. These results emphasize the paracrine role of factors secreted by activated fibroblasts in driving tumour progression. We also investigated the epithelial-mesenchymal transition (EMT) of the HaCaT clones in response to transforming growth factor β (TGF-β), which is a well-characterized inducer of EMT. TGF-β caused growth arrest and loss of epithelial cell junctions in the HaCaT derivatives, but mesenchymal markers were not induced, suggesting a partial, but not complete EMT response. Inflammation induced by COX-2 has been proposed to be a key mechanism in EMT of benign cells. Corroborating this notion, COX-2 was induced only in benign, not in malignant HaCaT derivatives. Furthermore, in cells in which TGF-β caused COX-2 induction, migration was clearly augmented. The concept of treating cancer is changing from targeting solely the cancer cells to targeting the whole microenvironment. The results of this work emphasise the role of activated fibroblasts in cancer progression and that CAFs should also be taken into consideration in the treatment of cancer. The results from these studies suggests that nemosis could be used as a diagnostic tool to distinguish in vitro activated fibroblasts from tumour stroma and also in studying the paracrine signalling that is mediated to other cell types via soluble factors.

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Väitöskirjani käsittele mikrobien ja erilaisten kemikaalien rooleja saostumien ja biofilmien muodostumisessa paperi- ja kartonkikoneilla. "Saostuma" tässä työssä tarkoittaa kiinteän aineen kertymää konepinnoille tai rajapinnoille konekierroissa, jotka on tarkoitettu massasulppujen, lietteiden, vesien tai ilman kuljetukseen. Saostumasta tulee "biofilmi" silloin kun sen oleellinen rakennekomponentti on mikrobisolut tai niiden tuotteet. Väitöstyöni työhypoteesina oli, että i. tietämys saostumien koostumuksesta, sekä ii. niiden rakenteesta, biologisista, fysikaalis-kemiallisista ja teknisistä ominaisuuksista ohjaavat tutkijaa löytämään ympäristöä säästäviä keinoja estää epätoivottujen saostumien muodostus tai purkaa jo muodostuneita saostumia. Selvittääkseni saostumien koostumista ja rakennetta käytin monia erilaisia analytiikan työkaluja, kuten elektronimikroskopiaa, konfokaali-laser mikroskopiaa (CLSM), energiadispersiivistä röntgenanalyysiä (EDX), pyrolyysi kaasukromatografiaa yhdistettynä massaspektrometriaan (Py-GCMS), joninvaihtokromatografiaa, kaasukromatografiaa ja mikrobiologisia analyysejä. Osallistuin aktiivisesti innovatiivisen, valon takaisinsirontaan perustuvan sensorin kehittämistyöhön, käytettäväksi biofilmin kasvun mittaukseen suoraan koneen vesikierroista ja säiliöistä. Työni osoitti, että monet paperinvalmistuksessa käytetyistä kemikaaleista reagoivat keskenään tuottaen orgaanisia tahmakerroksia konekiertojen teräspinnoille. Löysin myös kerrostumia, jotka valomikroskooppisessa tarkastelussa oli tulkittu mikrobeiksi, mutta jotka elektronimikroskopia paljasti alunasta syntyneiksi, alumiinihydroksidiksi joka saostui pH:ssa 6,8 kiertokuitua käyttävän koneen viiravesistä. Monet paperintekijät käyttävät vieläkin alunaa kiinnitysaineena vaikka prosessiolot ovat muuttuneet happamista neutraaleiksi. Sitä pidetään paperitekijän "aspiriinina", mutta väitöstutkimukseni osoitti sen riskit. Löysin myös orgaanisia saostumia, joiden alkuperä oli aineiden, kuten pihkan, saippuoituminen (kalsium saippuat) niin että muodostui tahmankasvua ylläpitävä alusta monilla paperi- ja kartonkikoneilla. Näin solumuodoiltaan Deinococcus geothermalista muistuttavia bakteereita kasvamassa lujasti teräskoepalojen pintaan kiinnittyneinä pesäkkeinä, kun koepaloja upotettiin paperikoneiden vesikiertoihin. Nämä deinokokkimaiset pesäkkeet voivat toimia jalustana, tarttumisalustana muiden mikrobien massoille, joka selittäisi miksi saostumat yleisesti sisältävät deinokokkeja pienenä, muttei koskaan pääasiallisena rakenneosana. Kun paperikoneiden käyttämien vesien (raakavedet, lämminvesi, biologisesti puhdistettu jätevesi) laatua tutkitaan, mittausmenetelmällä on suuri merkitys. Koepalan upotusmenetelmällä todettu biofilmikasvu ja viljelmenetelmällä mitattu bakteerisaastuneisuus korreloivat toisiinsa huonosti etenkin silloin kun likaantumisessa oli mukana rihmamaiseti kasvavia bakteereja. Huoli ympäristöstä on pakottanut paperi- ja kartonkikoneiden vesikiertojen sulkemiseen. Vesien kierrätys ja prosessivesien uudelleenkäyttö nostavat prosessilämpötilaa ja lisäävät koneella kiertävien kolloidisten ja liuenneiden aineiden määriä. Tutkin kiertovesien pitoisuuksia kolmessa eriasteisesti suljetussa tehtaassa, joiden päästöt olivat 0 m3, 0,5 m3 ja 4 m3 jätevettä tuotetonnia kohden, perustuen puhdistetun jäteveden uudelleen käyttöön. Nollapäästöisellä tehtaalla kiertovesiin kertyi paljon orgaanisesti sidottua hiiltä (> 10 g L-1), etenkin haihtuvina happoina (maito-, etikka-, propioni- ja voi-). Myös sulfaatteja, klorideja, natriumia ja kalsiumia kertyi paljon, > 1 g L-1 kutakin. Pääosa (>40%) kaikista bakteereista oli 16S rRNA geenisekvenssianalyysien tulosten perusteella sukua, joskin etäistä (< 96%) ainoastaan Enterococcus cecorum bakteerille. 4 m3 päästävältä tehtaalta löytyi lisäksi Bacillus thermoamylovorans ja Bacillus coagulans. Tehtaiden saostumat sisälsivät arkkeja suurina pitoisuuksina, ≥ 108 g-1, mutta tunnistukseen riittävää sekvenssisamanlaisuutta löytyi vain yhteen arkkisukuun, Methanothrix. Tutkimustulokset osoittivat että tehtaan vesikiertojen sulkeminen vähensi rajusti mikrobiston monimuotoisuutta, muttei estänyt liuenneen aineen ja kiintoaineen mineralisoitumista.

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The relationship between sexual reproduction of littoral chydorid cladocerans (Anomopoda, Chydoridae) and environmental factors in aquatic ecosystems has been rarely studied, although the sexual behavior of some planktonic cladocerans is well documented. Ecological monitoring was used to study the relationship between climate-related and non-climatic environmental factors and chydorid sexual reproduction patterns in nine environmentally different lakes that were closely situated to each other in southern Finland. Furthermore, paleolimnological ephippium analysis was used to clarify how current sexual reproduction is reflected in surface sediments of the same nine lakes. Additionally, short sediment cores from two of the lakes were studied with ephippium analysis to examine how recent climate-related and non-climatic environmental changes were reflected in chydorid sexual reproduction. Ephippium analysis uses the subfossil shells of asexual individuals to represent asexual reproduction and the shells of sexual females, i.e. ephippia, to represent sexual reproduction. The relative proportion of ephippia of all chydorid species, i.e. total chydorid ephippia (TCE) indicates the relative proportion of sexual reproduction during the open-water season. This thesis is part of the EPHIPPIUM-project which aims to develop ephippium analysis towards a quantitative climate reconstruction tool. To be able to develop a valid climate model, the influence of the environmental stressors other than climate on contemporary sexual reproduction and its reflection in sediment assemblages must be clarified so they can be eliminated from the model. During contemporary monitoring a few sexual individuals were observed during summer, apparently forced to sexual reproduction by non-climatic local environmental factors, such as crowding or invertebrate predation. Monitoring also revealed that the autumnal chydorid sexual reproduction period was consistent between the different lakes and climate-related factors appeared to act as the main inducers and regulators of autumnal sexual reproduction. However, during autumn, chydorid species and populations among the lakes exhibited a wide variation in the intensity, induction time, and length of autumnal sexual reproduction. These variations apparently act as mechanisms for local adaptations due to the genetic variability provided by sexual reproduction that enhance the ecological flexibility of chydorid species, allowing them to inhabit a wide range of environments. A large variation was also detected in the abundance of parthenogenetic and gamogenetic individuals during the open-water season among the lakes. On the basis of surface sediment samples, the general level of the TCE is ca. 3-4% in southern Finland, reflecting an average proportion of sexual reproduction in this specific climate. The variation in the TCE was much lower than could be expected on the basis of the monitoring results. This suggests that some of the variation detected by monitoring may derive from differences between sampling sites and years smoothed out in the sediment samples, providing an average of the entire lake area and several years. The TCE is always connected to various ecological interactions in lake ecosystems and therefore is always lake-specific. Hypothetically, deterioration of climate conditions can be detected in the TCE as an increase in ephippia of all chydorid species, since a shortening open-water season is reflected in the relative proportions of the two reproduction modes. Such an increase was clearly detected for the time period of the Little Ice Age in a sediment core. The paleolimnological results also indicated that TCE can suddenly increase due to ephippia of one or two species, which suggests that at least some chydorids can somehow increase the production of resting eggs under local environmental stress. Thus, some environmental factors may act as species-specific environmental stressors. The actual mechanism of the increased sexual reproduction seen in sediments has been unknown but the present study suggests that the mechanism is probably the increased intensity of gamogenesis, i.e. that a larger proportion of individuals in autumnal populations reproduce sexually, which results in a larger proportion of ephippia in sediments and a higher TCE. The results of this thesis demonstrate the utility of ephippium analysis as a paleoclimatological method which may also detect paleolimnological changes by identifying species-specific environmental stressors. For a quantitative TCE-based climate reconstruction model, the natural variation in the TCE of surface sediments in different climates must be clarified with more extensive studies. In addition, it is important to recognize the lakes where the TCE is not only a reflection of the length of the open-water season, but is also non-climatically forced. The results of ephippium analysis should always be interpreted in a lake-specific manner and in the context of other paleoecological proxies.

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Tools known as maximal functions are frequently used in harmonic analysis when studying local behaviour of functions. Typically they measure the suprema of local averages of non-negative functions. It is essential that the size (more precisely, the L^p-norm) of the maximal function is comparable to the size of the original function. When dealing with families of operators between Banach spaces we are often forced to replace the uniform bound with the larger R-bound. Hence such a replacement is also needed in the maximal function for functions taking values in spaces of operators. More specifically, the suprema of norms of local averages (i.e. their uniform bound in the operator norm) has to be replaced by their R-bound. This procedure gives us the Rademacher maximal function, which was introduced by Hytönen, McIntosh and Portal in order to prove a certain vector-valued Carleson's embedding theorem. They noticed that the sizes of an operator-valued function and its Rademacher maximal function are comparable for many common range spaces, but not for all. Certain requirements on the type and cotype of the spaces involved are necessary for this comparability, henceforth referred to as the “RMF-property”. It was shown, that other objects and parameters appearing in the definition, such as the domain of functions and the exponent p of the norm, make no difference to this. After a short introduction to randomized norms and geometry in Banach spaces we study the Rademacher maximal function on Euclidean spaces. The requirements on the type and cotype are considered, providing examples of spaces without RMF. L^p-spaces are shown to have RMF not only for p greater or equal to 2 (when it is trivial) but also for 1 < p < 2. A dyadic version of Carleson's embedding theorem is proven for scalar- and operator-valued functions. As the analysis with dyadic cubes can be generalized to filtrations on sigma-finite measure spaces, we consider the Rademacher maximal function in this case as well. It turns out that the RMF-property is independent of the filtration and the underlying measure space and that it is enough to consider very simple ones known as Haar filtrations. Scalar- and operator-valued analogues of Carleson's embedding theorem are also provided. With the RMF-property proven independent of the underlying measure space, we can use probabilistic notions and formulate it for martingales. Following a similar result for UMD-spaces, a weak type inequality is shown to be (necessary and) sufficient for the RMF-property. The RMF-property is also studied using concave functions giving yet another proof of its independence from various parameters.

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On the material level of poverty, the work shows how the Great Depression forced rural women and children to enhance their work input and find new ways of coping. The most serious impact of the Depression was poor nutrition, as well as scarcity of food and clothes. Women's and men's ways to make a living started to resemble each other; men had also to consent to wages in form of foodstuff. The research also focuses on immaterial poverty by means of exploring experiences of otherness: shame, hatred and expressions of protest. Substantial humiliation was induced by poor relief and begging. A clear gap prevailed between the poor and the better off people in school, work and at leisure. The economic crisis deepened this gap even further. The dissertation specifies the poor people s every day experiences by taking into account the different worlds of men and women. The analysis of four different memory-based sources is the core in the micro-historical research design. The narrators of the research were survivors, unlike many others, who experienced the Great Depression. Moralization and humiliation of the poor have not ceased in contemporary society. Therefore, the historical perspective of both the material and the immaterial side of poverty could increase the understanding of the multifaceted phenomenon of today s poverty.

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Since the Chinese government began implementing economic reforms in the late 1970s, China has experienced profound economic change and growth. Like other parts of China, Tibetan areas of China have also experienced wide-ranging economic change with growth even higher than the China-wide average in certain years. Though China s strategic policy of developing the West provided many opportunities for economic and business activities, Tibetans have proven poorly equipped to respond to and take advantage of these opportunities. This study is about people, about market participation and specifically about why Tibetans do not effectively participate in the market in the context of China s economic development process. Many political, social, cultural and environmental factors explain the difficulties met by Tibetan communities. However, this study focuses on three factors: the social and culture context, government policy and education. The Buddhistic nature of Tibetan communities, particularly the political and economic system in traditional Tibetan society, explains this, especially after implementation of new national economic policies. An inclusive economic development policy that promotes local people s participation in the market demands serious consideration of local conditions. Unfortunately, such considerations often ignore local Tibetan realities. The economic development policy in Tibetan areas in China is nearly always an attempt to replicate the inland model and open up markets, even though economic and sociopolitical conditions in Tibet are markedly unlike much of China. A consequence of these policies is increasing numbers of non-Tibetan migrants flowing into Tibetan areas with the ensuing marginalization of Tibetans in the marketplace. Poor quality education is another factor contributing to Tibetan inability to effectively participate in the market. Vocational and business education targeting Tibetans is of very low quality and reflective of government failing to consider local circumstances when implementing education policy. The relatively few Tibetans who do receive education are nearly always unable to compete with non-Tibetan migrants in commercial activity. Encouraging and promoting Tibetan participation in business development and access to quality education are crucial for a sustainable and prosperous society in the long term. Particularly, a localized development policy that considers local environmental conditions and production as well as local culture is crucial. Tibet s economic development should be based on local environmental and production conditions, while utilizing Tibetan culture for the benefit of creating a sustainable economy. Such a localized approach best promotes Tibetan market participation. Keywords: Tibet cultural policy education market participation