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  • Mattila, Kristiina (2010)
    The aims of this study were to describe Finnish day surgery practice at present and to evaluate quality of care by assessing postdischarge minor morbidity and quality indicators. Potential treatment options were approached by investigating the role of oral dexamethasone as a part of multimodal analgesia and the feasibility of day surgery in patients aged 65 years and older. Over a 2-month period, all patient cases at 14 Finnish day surgery or short-stay units were analyzed (Study I). Quality indicators included rates and reasons for overnight admission, readmission, reoperation, cancellations, and patient satisfaction. Recovery during the first postoperative week was assessed at two units (Study II). Altogether 2732 patients graded daily the intensity of predefined symptoms. To define risk factors of postdischarge symptoms, multinomial regression analysis was used. Sixty patients scheduled to undergo day surgery for hallux valgus were randomized to receive twice perioperatively dexamethasone 9 mg or placebo (Study III). Paracetamol 1 g was administered 3 times daily. Rescue medication (oxycodone) consumption during 0-3 postoperative days (POD), maximal pain scores and adverse effects were documented. Medically stable patients aged 65 years or older, scheduled for open inguinal hernia repair, were randomized to receive treatment either as day cases or inpatients (Study IV). Complications, unplanned admissions, healthcare visits, and patients’ acceptance of the type of care provided were assessed during 2 weeks postoperatively. In Study I, unplanned overnight admissions were reported in 5.9%, return hospital visits during PODs 1-28 in 3.7%, and readmissions in 0.7% of patients. Patient satisfaction was high. In Study II, pain was the most common symptom in adult patients (57%). Postdischarge symptoms were more frequent in adults aged < 40 years, children aged ≥ 7 years, females, and following a longer duration of surgery. In Study III, the total median (range) oxycodone consumption during the study period was 45 (0–165) mg in the dexamethasone group, compared with 78 (15–175) mg in the placebo group (P < 0.049). On PODs 0-1, patients in the dexamethasone group reported significantly lower pain scores. Following inguinal hernia repair, no significant differences in outcome measures were seen between the study groups. Patient satisfaction was equally high in day cases and inpatients (Study IV). Finnish day surgery units provide good-quality services. Minor postdischarge symptoms are common, and they are influenced by several patient-, surgery-, and anesthesia-related factors. Oral dexamethasone combined with paracetamol improves pain relief and reduces the need for oxycodone rescue medication following correction of hallux valgus. Day surgery for open inguinal hernia repair is safe and well accepted by patients aged 65 years or older and can be recommended as the primary choice of care for medically stable patients.
  • Zhang, Yiling (2014)
    Oat protein is a valuable cereal protein with high protein content and a good balance of amino acids profile. However, the inflexible molecular structure and poor watersolubility of oat protein limit its application in food industry. To exploit the food use of oat, the functionalities of oat proteins should be improved. α-chymotrypsin, a proteolytic enzyme, has been proven as being able to deamidate some food proteins without severe hydrolysis under alkaline pH conditions, hence to improve the protein functionalities. The aim of this research was to test whether oat protein could be deamidated by α- chymotrypsin under alkaline pH conditions. The extent of α-chymotrypsin-induced proteolysis on oat protein was also studied. Oat protein was treated by α-chymotrypsin under alkaline conditions from pH 8 to 11 at room temperature for 2 hours. The deamidation degrees of the proteins were measured by ammonia quantification. The hydrolysis degrees of proteins were analyzed by trichloroacetic acid precipitation and protein quantification method. The changes of molecular weights were analyzed by SDS-PAGE and SE-HPLC. The action of α-chymotrypsin under alkaline pH conditions induced slight deamidation of oat protein to low deamidation degrees (9-12%). On the other hand, α-chymotrypsin mainly caused hydrolysis of oat protein to hydrolysis degrees between 49% and 62%. SDS-PAGE and SE-HPLC analysis also revealed that significant hydrolysis of oat protein occurred during the reaction. The hydrolysis mainly caused the shift of oat protein fractions from molecular weight above 20 kDa to molecular weight below 15 kDa. Change in pH did not cause significant differences on deamidation degrees and hydrolysis degrees of oat protein In conclusion, oat protein could not be effectively deamidated by α-chymotrypsin under alkaline pH conditions, while the proteolysis was severe.
  • Holmlund, Ulrika (2003)
    Syftet med min pro gradu-avhandling är att undersöka på vilket sätt tidningspressen beskriver "de Andra". Jag har valt att operationalisera "de Andra" som utlänningar, både flyktingar, asylsökande och övriga invandrare, samt minoriteter. Materialet består av tidningstexter ur Vasabladet och Hufvudstadsbladet. Jag analyserade mina texter utgående från diskursanalysen. Jag tittade på vem som förde ordet i texten, samt vem och vad som lyftes fram i texten. Med hjälp av olika ord, begrepp och omskrivningar hittade jag exempel på hur konstruktionen av "de Andra" kan komma fram i tidningstexter. Jag utgick från att jag inte skulle hitta direkta uttryck för rasism i texterna. Därför valde jag en konkret fråga, det vill säga bilden av "de Andra" i tidningspressen, som jag undersökte empiriskt. I stället för att hitta direkta uttryck för rasism hittade jag generella uttryck som genom en överexponering kan klassas som en nyare form av rasism som inte är baserad på biologi, utan på individers kultur. Genom att beskriva och framhäva "de Andra" som annorlunda och exotiska tar man fram det som skiljer "Oss" från "Dem". Detta kan ske genom att poängtera "de Andras" kultur, exempelvis religion, språk, traditioner, kläder eller musik. Det annorlunda ses ofta som något främmande och "de Andra" kan därför ses som ett hot mot "Oss". Samtidigt som man exotiserar "de Andra" drar man gränser för vad som anses normalt och onormalt. I västvärlden anses ofta vitt vara det normala i motsats till svart. Genom att poängtera nationalitet skiljer man också "de Andra" från "Oss". Analysresultaten visar att massmedia tenderar att både exotisera och normalisera när det handlar om "de Andra". Centrala källor är: "Att tänka sociologiskt" av Z. Bauman; "Sverige och de Andra" av M. McEachrane och L. Faye; "Etnicitetsbilden i finlandssvenska medier" av T. Sandlund; "Etnisyys ja rasismi journalismissa" av P. Raittila och "Theories of race and racism: a reader" av L. Back och J. Solomos.
  • Muhonen, Riikkamari (2013)
    Tutkielma käsittelee neuvostonuorison tuottamia arkielämän julkisia representaatioita käyttäen lähteenään nuortenlehti Yunostiin lähetettyjä lukijakirjeitä. Tutkielma kuvaa arkielämän eri aspekteja, kuten ihmissuhteita, opiskelua ja työelämää, kiinnittäen erityistä huomiota yhteiskunnan arvojen, ideologian ja ihanteiden näkymiseen nuorten tuottamissa arkensa kuvauksissa. Tutkielman toinen keskeinen tutkimuskohde ovat itseilmaisun rajat neuvostoliittolaisessa journalismissa vuosina 1964-1982. Tutkielman tavoitteena on analysoida, millaisia kirjeitä julkaistiin, miten ne suhteutuivat yhteiskunnan viralliseen ideologiaan, millaisia yhteiskunnallisia epäkohtia oli mahdollista kritisoida ja millaisia elementtejä nuoriso pyrki korostamaan arkielämäänsä kuvatessaan. Käytetty lähdeaineisto koostuu Yunostissa vuosina 1964-1982 julkaistuista lukijakirjeistä, joita on yhteensä noin 250 kappaletta. Aineisto on jaoteltu temaattisesti kolmeen laajempaan alalukuun, joiden teemat ovat yhteiskunnan keskeisimmät arvot ja niitä ylläpitävät rakenteet, ihmissuhteet ja sukupolvien väliset erot, sekä ammatinvalinta ja työelämä. Analyysin teoreettisena pohjana toimivat Hans-Georg Gadamerin hermeneuttisen ymmärtämisen teoria sekä Quentin Skinnerin kontekstualisoiva tekstianalyysi. Tutkielman tavoite on suhteuttaa kirjeiden sisältö tutkimusajankohdan poliittisiin, sosiaalisiin ja kulttuurisiin konteksteihin hyödyntäen laajaa tutkimuskirjallisuutta historian, politiikan tutkimuksen ja sosiologian aloilta. Lisäksi neuvostoyhteiskuntaan olennaisella tavalla kuuluvat käsitteelliset vastaparit, kuten kollektiivisuus ja yksilöllisyys sekä julkisuus ja yksityisyys nousevat vahvasti esiin aineiston analyysissa. Tutkielma osoittaa, että neuvostolehdistön pyrkimys ohjata yleistä mielipidettä vallanpitäjien toivomaan suuntaan sekä valistaa lukijakuntaansa vaikutti vahvasti lukijakirjeitä koskevaan julkaisupolitiikkaan. Yhteiskunnallisesti aroista asioista kirjoitettaessa näiden representaatioiden tuli tukea lehden kasvatuksellisia päämääriä. Kriittisiä mielipiteitä oli mahdollista esittää julkisesti, jos kritiikki suunnattiin itse järjestelmän sijaan johonkin sen yksittäiseen osaan. Tällöin kritiikki saattoi olla itsekritiikkiä tai kannustusta yhteisiin ponnistuksiin yleisen hyvän lisäämiseksi. Suurin osa julkaistuista kirjeistä oli sävyltään ideologisia ja yhteiskunnan yleisiä ihanteita ja tavoitteita myötäileviä. Tämä näkyi esimerkiksi teollisuus- ja maatalousammattien voimakkaana korostamisena. Yhteiskunnalliset arvot ja ideologia näkyivät voimakkaasti kirjeissä, joiden tyylillisistä eroistaan huolimatta voi katsoa pyrkineen tukemaan ihanneyhteiskunnan rakentamisen prosessia.
  • Crentsil, Perpetual (Helsingin yliopisto, 2007)
    This is a study of crises caused by HIV/AIDS among the Akan of Ghana. It creates more awareness about the epidemic and has indicated other possible paths for campaign strategies. The pandemic has many devastating consequences; yet new infections are recorded daily despite campaigns against the disease. The search for therapy often sees the use of multiple outlets, which expresses Ghana's pluralistic medical system based on Kleinman's sector analytical model involving Western medicine, self-therapy, and folk healing. But it also leaves individuals and kin members in financial quandary. The fieldwork for this study is mainly through participant observation lasting 13 months (February 2003 to March 2004) among the Akan; in addition, some archival materials have been used. The Akan people live in the coastal south and forest zone of Ghana. Every Akan village or town is made up of corporate lineages, and social organisation is based on matrilineal descent. The society is holistic because the matrilineages seek the welfare of all their members. Meyer Fortes, R. S. Rattray and others on the Akan noticed this encompassing nature in the lineage organisation; but they did not make it salient (or failed to notice it) during illness, efforts for healing, and the care of the sick member. HIV/AIDS is an illness which shows the encompassing nature of the Akan matrilineage. It also reveals many contradictions in the group, viz. stigmatisation, abandonment, and attitudes that do not express altruism in a group expected to be closely-knit based on members' belief that they are of the 'same blood'. The crises have been analyzed in the total social system because the disease creates breaches at various levels of social interaction. An analysis of crises in a group is not far-fetched; Victor Turner has shown the way among the Ndembu and has revealed the contraditions in the seemingly uneventful life in the group. This study has identified that in dealing with HIV/AIDS patients and crises about the disease we are dealing with 'holistic' patients. Their cases produce many changes in the matrilineal structure--many orphans are being created and the care of patients is increasingly falling on the elderly. HIV/AIDS also challenges Akan cosmology because, for example, an AIDS death in local notions is a 'bad' demise which fails to produce ancestors who reproduce the society through reincarnation. Campaigns could emphasize this notion. The study begins with a description of the holistic nature of Akan matriliny, and the patients have been described as 'holistic' because their crises affect other people in the holistic society. Chapter 2 discusses the importance of ancestors as the starting points for social order who are constantly revered (in rites invoving the chief, Chapter 4). Chapter 3 focuses on funerals as an important social performance for the welfare of the dead and the living. Chapter 5 concentrates on HIV/AIDS as an illness threat marked by dominant discourses such as poverty, sexuality, migration, and condom use. Chapter 6 analyzes the attempts for therapy, and traditional healers' claims to have a cure. The efforts for therapy continues with spiritual church healing in Chapter 7, and chapter 8 is devoted to care of the patients and its inherent crises. Chapter 9 analyzes the effects of HIV/AIDS afflictions and AIDS deaths on the matrilineal group and in society. The study ends with a short part, devoted to Recommendations based on the findings in this investigation.
  • Wessman, Anna (Suomen Muinaismuistoyhdistys ry, 2010)
    The thesis is connected with death, memory and ancestor commemoration during the Merovingian Period, the Viking Age and the beginning of the Crusade Period (AD 550-1150) in Finland. During this time, cremation was the dominant burial rite. It was not until the end of the Viking Age that inhumation became more common but both cremations and inhumations are performed even at the same sites throughout the time. Three different burial types 1) cremation cemeteries below level ground, 2) inhumation burials and 3) water burials are discussed in five articles. I consider these burial forms from three different viewpoints; collectivity-individuality, visibility-invisibility and cremation-inhumation. The thesis also discusses the topics of memory, memorialisation and monument re-use, which have been neglected subjects in Finnish archaeology until now. Both cremation cemeteries below level ground and inhumation burials have been re-used during their time of usage, and on most occasions are situated in a landscape that is overlaid by other monuments as well. The main questions of the thesis are: What kinds of ritual behaviour can we detect in the burials during the period (AD 550-1150)? How did people perceive the moraine hills that functioned as burial places? What kind of re-use can be detected in the Iron Age cemeteries? Why have ancient sites and artefacts been re-used? This thesis shows that it is possible to claim that both artefact and site re-use is a much more widespread phenomenon than has previously been thought in Finnish archaeology. It is also a conscious and deliberate behaviour that can be related to an ancestor cult and commemoration of the dead. The funerary rituals during this time period show great variation and complex, both regionally and nationally. Not only have the dead been buried using elaborate rituals, they have also been mourned and commemorated in intricate ways that proves that death was not an end product, but the start of something new.
  • Korpisaari, Antti (Archaeopress, 2006)
    My Ph.D. dissertation presents a multi-disciplinary analysis of the mortuary practices of the Tiwanaku culture of the Bolivian high plateau, situated at an altitude of c. 3800 m above sea level. The Tiwanaku State (c. AD 500-1150) was one of the most important pre-Inca civilisations of the South Central Andes. The book begins with a brief introductory chapter. In chapter 2 I discuss methodological and theoretical developments in archaeological mortuary studies from the late 1960s until the turn of the millennium. I am especially interested in the issue how archaeological burial data can be used to draw inferences on the social structure of prehistoric societies. Chapter 3 deals with the early historic sources written in the 16th and 17th centuries, following the Spanish Conquest of the Incas. In particular, I review information on how the Incas manifested status differences between and within social classes and what kinds of burial treatments they applied. In chapter 4 I compare the Inca case with 20th century ethnographic data on the Aymara Indians of the Bolivian high plateau. Even if Christianity has affected virtually every level of Aymara religion, surprisingly many traditional features can still be observed in present day Aymara mortuary ceremonies. The archaeological part of my book begins with chapter 5, which is an introduction into Tiwanaku archaeology. In the next chapter, I present an overview of previously reported Tiwanaku cemeteries and burials. Chapter 7 deals with my own excavations at the Late Tiwanaku/early post-Tiwanaku cemetery site of Tiraska, located on the south-eastern shore of Lake Titicaca. During the 1998, 2002, and 2003 field seasons, a total of 32 burials were investigated at Tiraska. The great majority of these were subterranean stone-lined tombs, each containing the skeletal remains of 1 individual and 1-2 ceramic vessels. Nine burials have been radiocarbon dated, the dates in question indicating that the cemetery was in use from the 10th until the 13th century AD. In chapter 8 I point out that considerable regional and/or ethnic differences can be noted between studied Tiwanaku cemetery sites. Because of the mentioned differences, and a general lack of securely dated burial contexts, I feel that at present we can do no better than to classify most studied Tiwanaku burials into three broad categories: (1) elite and/or priests, (2) "commoners", and (3) sacrificial victims and/or slaves and/or prisoners of war. On the basis of such indicators as monumental architecture and occupational specialisation we would expect to find considerable status-related differences in tomb size, grave goods, etc. among the Tiwanaku. Interestingly, however, such variation is rather modest, and the Tiwanaku seem to have been a lot less interested in expending considerable labour and resources in burial facilities than their pre-Columbian contemporaries of many parts of the Central Andes.
  • Yu, Liying (Helsingin yliopisto, 2009)
    Programed cell death (PCD) is a fundamental biological process that is as essential for the development and tissue homeostasis as cell proliferation, differentiation and adaptation. The main mode of PCD - apoptosis - occurs via specifi c pathways, such as mitochondrial or death receptor pathway. In the developing nervous system, programed death broadly occurs, mainly triggered by the defi ciency of different survival-promoting neurotrophic factors, but the respective death pathways are poorly studied. In one of the best-characterized models, sympathetic neurons deprived of nerve growth factor (NGF) die via the classical mitochondrial apoptotic pathway. The main aim of this study was to describe the death programs activated in these and other neuronal populations by using neuronal cultures deprived of other neurotrophic factors. First, this study showed that the cultured sympathetic neurons deprived of glial cell line-derived neurotrophic factor (GDNF) die via a novel non-classical death pathway, in which mitochondria and death receptors are not involved. Indeed, cytochrome c was not released into the cytosol, Bax, caspase-9, and caspase-3 were not involved, and Bcl-xL overexpression did not prevent the death. This pathway involved activation of mixed lineage kinases and c-jun, and crucially requires caspase-2 and -7. Second, it was shown that deprivation of neurotrophin-3 (NT-3) from cultured sensory neurons of the dorsal root ganglia kills them via a dependence receptor pathway, including cleavage of the NT- 3 receptor TrkC and liberation of a pro-apoptotic dependence domain. Indeed, death of NT-3-deprived neurons was blocked by a dominant-negative construct interfering with TrkC cleavage. Also, the uncleavable mutant of TrkC, replacing the siRNA-silenced endogeneous TrkC, was not able to trigger death upon NT-3 removal. Such a pathway was not activated in another subpopulation of sensory neurons deprived of NGF. Third, it was shown that cultured midbrain dopaminergic neurons deprived of GDNF or brainderived neurotrophic factor (BDNF) kills them by still a different pathway, in which death receptors and caspases, but not mitochondria, are activated. Indeed, cytochrome c was not released into the cytosol, Bax was not activated, and Bcl-xL did not block the death, but caspases were necessary for the death of these neurons. Blocking the components of the death receptor pathway - caspase-8, FADD, or Fas - blocked the death, whereas activation of Fas accelerated it. The activity of Fas in the dopaminergic neurons could be controlled by the apoptosis inhibitory molecule FAIML. For these studies we developed a novel assay to study apoptosis in the transfected dopaminergic neurons. Thus, a novel death pathway, characteristic for the dopaminergic neurons was described. The study suggests death receptors as possible targets for the treatment of Parkinson s disease, which is caused by the degeneration of dopaminergic neurons.
  • Lorek, Sylvia (Helsingin yliopisto, 2009)
    Achieving sustainable consumption patterns is a crucial step on the way towards sustainability. The scientific knowledge used to decide which priorities to set and how to enforce them has to converge with societal, political, and economic initiatives on various levels: from individual household decision-making to agreements and commitments in global policy processes. The aim of this thesis is to draw a comprehensive and systematic picture of sustainable consumption and to do this it develops the concept of Strong Sustainable Consumption Governance. In this concept, consumption is understood as resource consumption. This includes consumption by industries, public consumption, and household consumption. Next to the availability of resources (including the available sink capacity of the ecosystem) and their use and distribution among the Earth’s population, the thesis also considers their contribution to human well-being. This implies giving specific attention to the levels and patterns of consumption. Methods: The thesis introduces the terminology and various concepts of Sustainable Consumption and of Governance. It briefly elaborates on the methodology of Critical Realism and its potential for analysing Sustainable Consumption. It describes the various methods on which the research is based and sets out the political implications a governance approach towards Strong Sustainable Consumption may have. Two models are developed: one for the assessment of the environmental relevance of consumption activities, another to identify the influences of globalisation on the determinants of consumption opportunities. Results: One of the major challenges for Strong Sustainable Consumption is that it is not in line with the current political mainstream: that is, the belief that economic growth can cure all our problems. So, the proponents have to battle against a strong headwind. Their motivation however is the conviction that there is no alternative. Efforts have to be taken on multiple levels by multiple actors. And all of them are needed as they constitute the individual strings that together make up the rope. However, everyone must ensure that they are pulling in the same direction. It might be useful to apply a carrot and stick strategy to stimulate public debate. The stick in this case is to create a sense of urgency. The carrot would be to articulate better the message to the public that a shrinking of the economy is not as much of a disaster as mainstream economics tends to suggest. In parallel to this it is necessary to demand that governments take responsibility for governance. The dominant strategy is still information provision. But there is ample evidence that hard policies like regulatory instruments and economic instruments are most effective. As for Civil Society Organizations it is recommended that they overcome the habit of promoting Sustainable (in fact green) Consumption by using marketing strategies and instead foster public debate in values and well-being. This includes appreciating the potential of social innovation. A countless number of such initiatives are on the way but their potential is still insufficiently explored. Beyond the question of how to multiply such approaches, it is also necessary to establish political macro structures to foster them.
  • Heikka, Henrikki (1999)
    The origin of security dilemmas has long been a central question in international relations. Three archetypal models of the security dilemma can be found in international relations literature. According to the spiral model, security dilemmas are driven by the inability of security-seeking states to coordinate their policies in an anarchic political space, while the deterrence model implies that security dilemmas are caused by the offensive intentions of at least one of the actors in an anarchic system. Advocates of the model of peaceful change, in turn, maintain that security dilemmas are nothing more than a social construction: anarchy is what states make of it. In this thesis I deconstruct and reconstruct some key aspects of security dilemma theories in a hitherto unexplored (meta)theoretical context, that of Jacques Lacan's psychoanalytical theory. The aim of the thesis is to show how a Lacanian interpretation of one phenomenon - "predationism" - can help us locate the logic of all three models described above (international relations as tragedy, evil, and a social construction) within one theoretical framework. The thesis is structured around two parts. The first part deals with explaining the origins of anti-Western sentiments in the discourse of Russian "enlightened patriotism". I begin the study by reviewing contemporary neorealist and constructivist analyses of Russian foreign policy. Through a close reading of Waltzian neorealism and Wendtian constructivism I then show how the causal logics of both theories, despite their many differences, presume the existence of a phenomenon usually referred to as predationism (an aggressive policy of seeking non-security goals), which neither theory can explicate in scientific terms. Relying on Lacan and Slavoj Žižek, I conceptualize predationism as a cultural and political effort to escape the lack arising from representation by displacing it to a Symbolic Other, which is constructed as threatening, inferior, degenerate etc., and whose function in political discourse is to enable collectives to maintain the illusion of national/ethnic/civilizational unity. I demonstrate the potential usefulness of Lacanian discourse analysis by applying it to the thinking of Sergei Kortunov, a prominent Kremlin strategist, who has written extensively on Russian identity and foreign policy. Kortunov's anti-Westernism, I conclude, is not so much a reaction to Western deeds (as constructivism would suggest) or to the structure of the international system (as neorealism would lead us to believe) as a symptom of a discursive structure where the split inherent in identity is displaced to the Western Other in order to rescue the fantasy of an organic Russia from its own impossibility. In the second part of the thesis, I make three moves in order to place the Lacanian-inspired explanation for predationism within the context of security dilemma theory. I begin by elaborating the relationship between the Lacanian reading of alienation and the interpretation of estrangement in the philosophy of the Enlightenment. Next, after tracing the imprints of the Enlightenment within contemporary objectivist, subjectivist, and intersubjectivist security dilemma theories, I suggest how a Lacanian reading of estrangement can help us (re)locate the role of culture in the formation of different kinds of security dilemmas. Finally, I propose some guidelines under which a dialogue between a structuralist understanding of the logic of anarchy and a Lacanian-inspired structuralist theory of the origins of threat perceptions could be developed into a research programme and how this programme could be evaluated. I sum up the thesis with a chapter in which I reflect on the potential usefulness of Lacanian theory for policy research. The main source material of the thesis consists of academic literature dealing with international relations theory, political theory, psychoanalysis and Russian foreign policy. The case study on Sergei Kortunov's thinking is based on his recent articles and books.
  • Heikka, Henrikki (1999)
    Turvallisuusdilemmojen alkuperä on pitkään ollut kansainvälisen politiikan tieteenalan keskeisiä tutkimusaiheita. Tutkimuskirjallisuudesta voidaan löytää kolme arkkityyppistä turvallisuusdilemmamallia. Spiraalimallin mukaan turvallisuusdilemmat johtuvat turvallisuutta maksimoivien toimijoiden kyvyttömyydestä koordinoida vuorovaikutustaan anarkisessa poliittisessa tilassa. Deterrenssimallin mukaan turvallisuusdilemmojen taustalla on jonkun toimijan aidosti hyökkäykselliset aikeet. Rauhanomaisen muutoksen malli puolestaan perustuu oletukselle, jonka mukaan turvallisuusdilemmat ovat vain sosiaalisia konstruktioita eikä kansainvälinen anarkia sinänsä aseta mitään pidäkkeitä valtioiden yhteistyölle. Tässä tutkimuksessa dekonstruktoin ja rekonstruktoin turvallisuusdilemmateorian keskeisiä oletuksia lacanilaiseen psykoanalyysiin pohjautuvassa (meta)teoreettisessa viitekehyksessä. Tutkimuksen keskeinen pyrkimys on osoittaa kuinka lacanilainen tulkinta "predationismista" - hyokkäyksellisestä politiikasta, jonka pyrkimykset eivät palaudu turvallisuuden maksimointiin - mahdollistaa kaikkien kolmen edellä esitetyn mallin (kansainvälinen politiikka tragediana, pahuuden näyttämönä ja sosiaalisena konstruktiona) logiikan ymmärtämisen yhden teoreettisen viitekehyksen puitteissa. Tutkimus jakaantuu kahteen osaan. Ensimmäisessä osassa tarkastelen venäläiseen "valistuneeseen patriotismiin" liittyvän länsivastaisuuden logiikkaa. Tutkimuksen aluksi luon katsauksen läntisen tutkimuksen valtavirtaa edustaviin konstruktivistisiin ja neorealistisiin tulkintoihin Venäjän ulkopolitiikasta. Käsittelemällä perusteellisemmin Waltzilaiseen neorealismiin ja Wendtiläiseen konstruktivismiin sisältyviä kausaalisia oletuksia pyrin osoittamaan, kuinka molempien teorioiden selitys turvallisuusdilemmojen alkuperästä edellyttää "predationismina" tunnetun ilmiön olemassaolon. Tarkasteluni osoittaa myös, ettei kumpikaan teoria kykene esittämään tietellistä määritelmää ilmiölle saatikka vastaamaan kysymykseen siitä, mikä kyseisen ilmiön saa aikaiseksi. Nojautuen Jacques Lacanin ja Slavoj Žižekin teorioihin ja käsitteisiin pyrin ottamaan ensi askelen ilmiön ymmärtämisessä määrittelemällä predationismin poliittiseksi ja kulttuuriseksi ponnistukseksi, jossa yhteisö pyrkii pakenemaan representaation synnyttämää puutetta sijoittamalla sen Symboliseen Toiseen, mikä mahdollistaa kansallisen, etnisen, tai sivilisaation yhtenäisyyden illuusion ontologisen perustan säilymisen. Tutkin lacanilaisen diskurssianalyysin käyttökelpoisuutta soveltamalla sitä Sergei Kortunovin, Venäjän kansallisen turvallisuuden strategian parissa työskentelevän virkamiehen, teksteihin. Analyysini valossa Kortunovin länsivastaisuus ei näytä johtuvan niinkään länsivaltioiden toimista (konstruktivistinen selitys) tai kansainvälisen järjestelmän rakenteesta (neorealistinen selitys), vaan diskursiivisesta rakenteesta, jossa fantasia Venäjän orgaanisesta ykseydestä pelastetaan omalta mahdottomuudeltaan heijastamalla identiteetin jakautuneisuuden syy läntisen toiseuden merkityksellistäjiin. Tutkimuksen toisessa osassa pyrin sijoittamaan lacanilaisen predationismi-selityksen turvallisuusdilemmateorian viitekehykseen. Pohdittuani ensin Lacanilaisen vieraantumiskäsitteen suhdetta Valistuksen filosofiaan, käsittelen jälkimmäisen läsnäoloa objektivistisissa, subjektivistisissa ja intersubjektivistisissa turvallisuusdilemmateorioissa. Vaihtoehtona näille esitän mahdollisuutta yhdistää lacanilainen poliittisen kulttuurin tason selitysmalli rakenteelliseen tulkintaan kansainvälisestä anarkiasta ja tuoda siten falsifioitavissa olevia hypoteeseja predationismista turvallisuusdilemmateorian piiriin. Lopuksi käsittelen sitä, kuinka rakenteellisen realismin tulkinta anarkian logiikasta ja lacanilainen (rakenteellinen) tulkinta uhkakuvien alkuperästä voitaisiin yhdistää tutkimusohjelmaksi ja kuinka tämän tutkimusohjelman väitteitä voitaisiin evaluoida. Tutkimuksen lähdemateriaalina on käytetty kansainvälisen politiikan teoriaa, politiikan teoriaa, psykoanalyysiä ja Venäjän ulkopolitiikkaa käsittelevää tutkimuskirjallisuutta. Sergei Kortunovin ajattelua käsittelevän tapaustutkimuksen lähteinä on käytetty hänen viimeaikaisia julkaisujaan.
  • Penttala-Långbacka, Kaija (1999)
    The main purpose of this study is examine business managers' and teachers' professional morality by evaluating their decision-making strategies in hypothetical social conflict situations. Additionally, the values of these professionals and the relationship to the, decision-making strategies were examined. The replies of business managers have been compared to those of teachers. Similarly, comparisons have been done between the replies of female and male participants. The theoretical frame of professional morality has been constructed using James Rest's (1984, 1986) theory of morality and the theory of teachers' professional morality by Fritz Oser (1991, 1994). The theoretical basis of the value survey is based on the theory of values by Shalom Schwartz (1992). The empirical data consists of questionnaires of 66 business managers and 83 teachers concerning decision making strategies in hypothetical workplace moral dilemmas, values and background information. Additionally, questions concerning the internal communication and co-operation in their present working environment and their organizational commitment were included. Subjects were also randomly assigned to four conditions in which social consensus (low-high) and personal proximity, (close-distant) were manipulated as different variables. This part of the research project is based on analysis, t-tests, regression analysis and factor analysis. According to the results the gender was most significant predictor in selection of decision making strategies in solving hypothetical moral dilemmas. Female respondents used statistically significantly more often discursive decision making strategies in three of five dilemmas. Business managers' and teachers' decision making strategies differed statistically significantly only in one dilemma. Teachers used more often discursive strategies than business managers. Social consensus and personal proximity did not have significant connections to decision making strategies. In value preferences business managers and teachers had more differences. The major diiferences between these professional groups were in valuating achievement, universalism, stimulation, tradition. The values of universalism and tradition were more important for the teachers than for the business managers. The most prominent value type in both professional groups was social harmony. Differences between female and male participants were found in three value types; the female participants valued more values of social harmony than male participants and the male participants the values of tradition and conformity. The relationship between values and decision making strategies was also studied. Participants who valued values of achievement, power and hedonism did use less discursive decision making strategies. Also internal communication and co-operation in the working environment had significant connection to the decision making strategies. Participants who had evaluated the internal communication and co-operation in their working environment to be low used less discursive strategies.
  • Zaitsev, Kira (Helsingin yliopisto, 2014)
    Emmanuel Levinas on ranskanjuutalainen filosofi, jonka filosofia keskittyy etiikkaan ja toisen kohtaamiseen. Tämä pro gradu keskittyy Levinaksen estetiikkaan, joka on riippuvainen hänen ”ensimmäisestä filosofiastaan”, eli etiikasta. !Työn tutkimuskysymykset ovat Kuinka Levinaksen estetiikka on muodostunut sekä kuinka Mark Rothkon Seagram Murals-maalauksia tulisi arvioida Levinaksen estetiikan pohjalta. Tämän lisäksi työ pohdiskelee juutalaisen filosofian mahdollisuutta ja fiosofian luonnetta. !Pro gradussa arvioidaan ensin Levinaksen laajempaa filosofiaa feministisen dekonstruktion avulla, joka paljastaa filosofian näennäisen rationaalisuuden ja Levinaksen naisvihamielisen paikantumisen. Tämän jälkeen gradussa arvioidaan Levinaksen estetiikkaa ja pohditaan Levinaksen estetiikan rajoja ensin tarkastelemalla Levinaksen argumenttien koherenttiutta hyväksikäyttäen Jacques Derridan kuva — merkki-analyysia, ja tämän jälkeen soveltamalla feministisen dekonstruktion paljastamia ongelmia spesifisti estetiikkaan. Lopuksi analysoin Mark Rothkon The Seagram murals-maalauksia käyttäen Levinaksen estetiikkaa, sekä vertaan sitä Rothkon omiin kirjoituksiin. !Tämä työ tulee siihen tulokseen, että Levinaksen etiikka sekä estetiikka pohjaa juutalaisuuteen, ja näin ollen on oikeutettua puhua juutalaisesta filosofiasta. Levinaksen etiikkaa kuitenkin heikentää hänen naisvihamielisyytensä, joka heikentää hänen esteettisiä argumenttejaan. Levinaksen pohjalta Rothkoa ja hänen töitään tulisi arvioida mukavuustuotteena, joka ei kuitenkaan täytä Levinaksen eettisen toiminnan määreitä.
  • Granvik, Anton (Helsingin yliopisto, 2012)
    El presente estudio supone un intento de describir y analizar el uso de la preposición "de" sobre la base de un corpus diacrónico, con énfasis en las diferentes relaciones semánticas que establece. Partiendo de un total de más de 16.000 casos de "de" hemos establecido 48 categorías de uso, que corresponden a cuatro tipos de construcción sintáctica, a saber, el uso de "de" como complemento de nombres (CN), verbos (CV), adjetivos (CA) y, finalmente, su uso como núcleo de expresiones adverbiales independientes (CI). El estudio consta de tres partes fundamentales. En la parte I, se introduce la Lingüística Cognitiva, que constituye la base teórica esencial del trabajo. Más exactamente, se introducen conceptos como la teoría del prototipo, la teoría de las metáforas conceptuales y la gramática cognitiva, especialmente las ideas de "punto de referencia" y "relación intrínseca" (Langacker 1995, 1999). La parte II incluye el análisis de las 48 categorías. En esta parte se presentan y comentan casi 2.000 ejemplos del uso contextual de "de" extraídos del corpus diacrónico. Los resultados más importantes del análisis pueden resumirse en los siguientes puntos: El uso de "de" sigue siendo esencialmente el mismo en la actualidad que hace 800 años, en el sentido de que todas las 48 categorías se identifican en todas las épocas del corpus. El uso de "de" como complemento nominal va aumentando, al contrario de lo que ocurre con su uso como complemento verbal. En el contexto nominal son especialmente las relaciones posesivas más abstractas las que se hacen más frecuentes, mientras que en el contexto verbal las relaciones que se hacen menos frecuentes son las de separación/alejamiento, causa, agente y partitivo indefinido. Destaca la importancia del siglo XVIII como época de transición entre un primer estado de las cosas y otro posterior, en especial en relación con el carácter cada vez más abstracto de las relaciones posesivas así como con la disminución de las categorías adverbales de causa, agente y partitivo. Pese a la variación en el contexto inmediato de uso, el núcleo semántico de "de" se mantiene inalterado. La parte III toma como punto de partida los resultados del análisis de la parte II, tratando de deslindar el aporte semántico de la preposición "de" a su contexto de uso del valor de la relación en conjunto. Así, recurriendo a la metodología para determinar el significado básico y la metodología para determinar lo que constituyen significados distintos de una preposición (Tyler , Evans 2003a, 2003b), se llega a la hipótesis de que "de" posee cuatro significados básicos, a saber, 'punto de partida', 'tema/asunto', 'parte/todo' y 'posesión'. Esta hipótesis, basada en las metodologías de Tyler y Evans y en los resultados del análisis de corpus, se intenta verificar empíricamente mediante el uso de dos cuestionarios destinados a averiguar hasta qué punto las distinciones semánticas a las que se llega por vía teórica son reconocidas por los hablantes nativos de la lengua (cf. Raukko 2003). El resultado conjunto de los dos acercamientos tanto refuerza como especifica la hipótesis. Los datos que arroja el análisis de los cuestionarios parecen reforzar la idea de que el núcleo semántico de "de" es complejo, constando de los cuatro valores mencionados. Sin embargo, cada uno de estos valores básicos constituye un prototipo local, en torno al cual se construye un complejo de matices semánticos derivados del prototipo. La idea final es que los hablantes son conscientes de los cuatro postulados valores básicos, pero que también distinguen matices más detallados, como son las ideas de 'causa', 'agente', 'instrumento', 'finalidad', 'cualidad', etc. Es decir, "de" constituye un elemento polisémico complejo cuya estructura semántica puede describirse como una semejanza de familia centrada en cuatro valores básicos en torno a los cuales se encuentra una serie de matices más específicos, que también constituyen valores propios de la preposición. Creemos, además, que esta caracterización semántica es válida para todas las épocas de la historia del español, con unas pequeñas modificaciones en el peso relativo de los distintos matices, lo cual está relacionado con la observada variación diacrónica en el uso de "de".
  • Kairavuo, Annika (2015)
    Syftet med denna pro gradu-avhandling är att få en uppfattning om föräldrars upplevelser då de har ett barn med ett normbrytande beteende. De tre centrala forskningsfrågorna är; ”Hurdana upplevelser har föräldrar till barn med normbrytande beteende om familjens situation?”, ”Vilken betydelse har olika system i bemötandet av familjer där det finns barn med normbrytande beteende?” samt ”Vilka faktorer har haft störst betydelse i familjernas situationer?”. Informationen är insamlad genom att göra kvalitativa öppna intervjuer med sju föräldrar. Det gemensamma för föräldrarna är att de har deltagit i Folkhälsans kurs ”Explosiv – vilse i skolan”. Det insamlade materialet har analyserats genom att göra en kvalitativ teoristyd innehållsanalys. Fokus i analysen har till en rätt så stor del utgått ifrån Urie Bronfenbrenners (1979) ekologiska systemteori. Denna teori fungerar som den övergripande teoretiska referensramen i föreliggande pro gradu-avhandling. Systemteorin utgår enligt Bronfenbrenner ifrån att människan ingår i flera olika både närliggande och mer övergripande system. Människan både påverkas av och påverkar dessa system. För att kunna förstå en människas utveckling och situation anser Bronfenbrenner att det är viktigt att se på alla de system eller miljöer som personen ingår i samt även systemens samspel. Resultaten av denna avhandling visar att det finns faktorer inom både familjesystemet, näromgivningen, skolsystemet och det övergripande samhälleliga systemet som har en påverkan på familjernas situationer. Familjen och dess fungerande verkar ha en stor roll med tanke på hur föräldrarna upplever sin situation. Här talas särskilt om en god relation till både partnern och barnet. Samtidigt lyfts skolmiljön fram som en betydande miljö. Här fanns både positiva och negativa erfarenheter. Det handlar till en stor del om hur familjerna blivit bemötta samt hurdana resurser och hurdant stöd som erbjuds i skolan. För övrigt kan föräldrarna känna att det samhälleliga systemet är rörigt. Det talas om att man inte vet vart man ska söka sig för att få hjälp men också om att bli bollad från ett ställe till ett annat. Det verkar inte finnas en enhetlig linje i fråga om vem som sköter vad. Det verkar även som att en diagnos har en viss betydelse i särskilt förståelsen för barnets beteende samt bemötandet av både föräldrar och barn. Sammanfattningsvis kan konstateras att det inom de system som familjerna ingår i finns både styrkor och svagheter. Här spelar bland annat övergripande samhälleliga stödformer samt även normer och attityder en central roll. I relation till systemteorin kan man se det som att de övergripande strukturerna och normerna har en påverkan på de mer närliggande system som familjerna ingår i. Detta kan ses exempelvis med tanke på hurdant stöd som erbjuds och fås samt på vilket sätt man ser på fenomenet barn med normbrytande beteende. Normerna och attityderna kan påverka bemötandet av familjerna inom flera olika system.
  • Ylisaukko-oja , Sanna (Helsingin yliopisto, 2007)
    Hereditary leiomyomatosis and renal cell cancer (HLRCC) is a recently characterized cancer syndrome which predisposes to cutaneous and uterine leiomyomas as well as renal cell carcinoma (RCC). Uterine leiomyosarcoma (ULMS) has also been observed in certain Finnish HLRCC families. The predisposing gene for this syndrome, fumarate hydratase (FH), was identified in 2002. The well-known function of FH is in the tricarboxylic acid cycle (TCAC) in the energy metabolism of cells. As FH is a novel cancer gene, the role of FH mutations in tumours is in general unknown. Similarly, the mechanisms through which defective FH is associated with tumourigenesis are unclear. The loss of a wild type allele has been observed in virtually all HLRCC patients tumours and the FH enzyme activities are either totally lost or remarkably reduced in the tissues of mutation carrier patients. Therefore, FH is assumed to function as a tumour suppressor. Mutations in genes encoding subunits of other TCAC enzyme SDH have also been reported recently in tumours: mutations in SDHB, SDHC, and SDHD genes predispose to paraganglioma and pheochromocytoma. In the present study, mutations in the SDHB gene were observed to predispose to RCC. This was the first time that mutations in SDHB have been detected in extra-paraganglial tumours. Two different SDHB mutations were observed in two unrelated families. In the first family, the index patient was diagnosed with RCC at the age of 24 years. Additionally, his mother with a paraganglioma (PGL) of the heart and his maternal uncle with lung cancer were both carriers of the mutation. The RCC of the index patient and the PGL of his mother showed LOH. In the other family, an SDHB mutation was detected in two siblings who were both diagnosed with RCC at the ages of 24 and 26 years. Both of the siblings also suffered PGL. All these tumours showed LOH. Therefore, we concluded that mutations in SDHB predispose also for RCC in certain families. Several tumour types were analysed for FH mutations to define the role of FH mutations in these tumour types. In addition, patients with a putative cancer phenotype were analysed to identify new HLRCC families. Three FH variants were detected, of which two were novel. One of the variants was observed in a patient diagnosed with ULMS at the age of 41 years. However, LOH was not detected in the tumour tissue. The FH enzyme activity of the mutated protein was clearly reduced, being 43% of the activity of the normal protein. Together with the results from an earlier study we calculated that the prevalence of FH mutations in Finnish non-syndromic ULMS is around 2.4%. Therefore, FH mutations seem to have a minor role in the pathogenesis on non-syndromic ULMS. Two other germline variants were detected in a novel tumour type, ovarian mucinous cystadenoma. However, tumour tissues of the patients were not available for LOH studies and therefore LOH status remained unclear. Therefore, it is possible that FH mutations predispose also for ovarian tumours but further studies are needed to verify this result. A novel variant form of the FH gene (FHv) was identified and characterized in more detail. FHv contains an alternative first exon (1b), which appeared to function as 5 UTR sequence. The translation of FHv is initiated in vitro from exons two and three. The localization of FHv is both cytosolic and nuclear, in contrast to the localization of FH in mitochondria. FHv is expressed at low levels in all human tissues. Interestingly, the expression was induced after heat shock treatment and in chronic hypoxia. Therefore, FHv might have a role e.g. in the adaptation to unfavourable growth conditions. However, this remains to be elucidated.
  • Autio, Ilari (2014)
    Osakeyhtiöiden elinkaari päättyy useimmiten joko yhtiön konkurssiin tai yrityskauppaan, joiden jälkeen yhtiö joko lakkaa olemasta tai muodostaa merkittävässä määrin uuden kokonaisuuden. Yrityskaupat ovat markkinoiden suurimpia tapahtumia, joita valmistellaan ja joiden vaikutuksia selvitellään kuukausia tai jopa vuosia. Ostettavan listayhtiön osakkeenomistajien näkökulmasta olennaista on yrityskaupasta saatavan vastikkeen suuruus heidän omistuksestaan yhtiöstä. Käytännössä kyse on osakkeen markkinahintaan lisättävän preemion suuruudesta, sillä listayhtiön osakkeenomistajan oletetaan saavan osakkeistaan markkinaarvon mukaisen korvauksen, mikäli hän myy omistuksensa julkisilla arvopaperimarkkinoilla. Lähtökohtaisesti yhtiön johdon ajaessa yhtiön ja sen osakkeenomistajien etua heidän tulee pyrkiä maksimoimaan osakkeen arvo. Myös yritysvaltauksessa, normaalissa tai vihamielisessä, yhtiön johdon tulee toimia velvollisuuksiensa mukaan, jolloin osakkeen arvo maksimoidaan maksimoimalla osakkeesta maksettavan preemion määrä. Vihamielisessä yritysvaltauksessa kohdeyhtiön johto ei hyväksy ostotarjouksen tehneen yhtiön tarjousta osakkeista eikä tee yhteistyötä tarjouksen tehneen yhtiön kanssa. Syyt tähän vaihtelevat, mutta eräs merkittävänä pidetty syy tarjouksen vastustamiseen on johtajien riski menettää asemansa yhtiössä, sillä useimmissa tapauksissa kohdeyhtiön johto vaihdetaan onnistuneen yrityskaupan jälkeen. Johdon oman aseman säilyttäminen ei kuitenkaan ole johdon tehtävä ja velvollisuus, vaan sen tulisi säilyä osakkeenomistajille lojaalina huolimatta mahdollisuudesta ja uhasta menettää oma asemansa. Yritysvaltauksessa, jota kohdeyhtiön johto ei hyväksy, vastakkain asettuvat johdon henkilökohtaiset sekä yhtiön ja sen osakkeenomistajien intressit. Oikeus- ja taloustieteellisessä kirjallisuudessa on kyseenalaistettu puolustautumista vihamielistä yritysvaltausyritystä vastaan, mutta käytännössä näitä esiintyy jatkuvasti. Tämän takia on perusteltua tutkia vaihtoehtoisia puolustuskeinoja. Vihamielistä yritysvaltausyritystä vastaan voi puolustautua monin keinoin riippuen sovellettavasta lainsäädännöstä. Suosittuja keinoja ovat valtausta yrittävän yrityksen toimintamahdollisuuksien rajaaminen esimerkiksi yhtiöjärjestykseen sisältyvällä määräyksellä sekä yhtiön taloudellisen aseman uudelleenjärjestely siten, että yhtiön markkina-arvo nousee. Osakeanti nostaa yhtiön markkina-arvoa osakkeista maksettavan vastikkeen verran ilman että yhtiölle aiheutuu muita kuin osakkeiden liikkeelle laskemiseen liittyviä kustannuksia. Yhtiön markkina-arvon noustessa valtaaja joutuu usein hankkimaan ulkopuolista lisärahoitusta, mikä lisää valtauksen kustannuksia jopa siinä määrin, että valtaajan kiinnostus viedä valtaus loppuun vähenee riittävästi. Toisaalta kohdeyhtiölle ei aiheudu merkittävää tai pysyvää haittaa. Koska osakeantipuolustus täytyy toteuttaa suuntaamalla osakeanti tietyille osakkeenomistajille, sen käytössä on huomioitava osakkeenomistajien yhdenvertaisuus. Lähtökohtaisesti suunnattu osakeanti loukkaa osakkeenomistajien yhdenvertaisuutta, joten sille on oltava sovellettavasta laista riippuen riittävän painava syy. Suomen osakeyhtiölaki (21.7.2006/624) ei mahdollista suunnatun osakeannin käyttämistä tilanteissa, joissa tarkoituksena on säilyttää jonkun tai joidenkin omistajien kontrolliasema. Suunnatun osakeannin käyttäminen puolustuskeinona vihamielistä yritysvaltausta vastaan voi periaatteessa kuitenkin pitää mahdollisena poikkeuksena, kunhan yhdenvertaisuusvaatimus otetaan huomioon. Vaikka osakeantipuolustus ei ole puolustuskeinoista tehokkain, se voi olla osakkeenomistajien enemmistölle houkutteleva vaihtoehto sen edullisuuden ja yhtiön toimintaa haittaamattoman vaikutuksen takia.
  • Qian, Yuchen (2013)
    Collaborative applications like online markets, social network communities, and P2P file sharing sites are in popular use these days. However, in an environment where entities have had no interaction before, it is difficult to make trust decisions on a new transacting partner. To predict the quality of further interactions, we need a reputation system to help establish trust relationships. Meanwhile, motivated by financial profit or personal gain, attackers emerge to manipulate the reputation systems. An attacker may aim to slander others, promote oneself, or undermine the whole reputation system. Vulnerable components in a reputation system might bring in potential threats which might be taken advantage of by attackers. In order to give an accurate reputation estimate and better user satisfaction, a reputation system should properly reflect the behavior of the participants and should be difficult to manipulate. To resist attacks, there are various defense mechanisms, for example, mitigating the generation and spreading of false rumors, reasonably assigning an initial reputation value to newcomers, and gradually discounting old behavior. However, each defense mechanism has limitations. There is no perfect defense mechanism which can resist all attacks in all environments without any trade-offs. As a result, to make a reputation system more robust, we need to analyze its vulnerabilities and limitations, and then utilize the corresponding defense mechanisms into it. This thesis conducts a literature survey on reputation systems, inherent vulnerabilities, different kinds of attack scenarios, and defense mechanisms. It discusses the evolution of attacks and defense mechanisms, evaluates various defense mechanisms, and proposes suggestions on how to utilize defense mechanisms into reputation systems.
  • Kontinen, Juha (Helsingin yliopisto, 2004)
  • Viljakainen, Heli Tuulikki (Helsingin yliopisto, 2008)
    Vitamin D is required for normal bone growth and maintenance of the skeleton throughout life. In Finland, like in many other Western countries, the population suffers from inadequate or deficient vitamin D status, especially during winter, which is thought to increase the risk of osteoporosis. New strategies to prevent osteoporosis are actively being sought. The main objective of this thesis was to determine whether vitamin D is feasible in the primary prevention of osteoporosis; does it affect bone mineral accrual during the growth period? A second goal was to ascertain whether seasonal variation in calcitropic hormones affects bone remodelling, and to elucidate the vitamin D intake needed to overcome this variation in different age groups. The subjects were healthy, free-living representatives of their respected age groups: 11- to 12-year-old girls (N=228), 21- to 49-year-old men (N=54) and 65- to 85-year-old women (N=52). Subjects participated in an intervention trial in which they were randomly assigned to a group receiving 0, 5, 10 or 20 µg of vitamin D as a supplement. All studies were performed double-blinded. Fasting blood and urine samples were collected together with data about, for instance, dietary intake of calcium and vitamin D and physical activity. In two studies bone mineral density (BMD) of subjects was measured at enrolment and at the end of the study. Laboratory analysis consisted of measurements of serum 25-hydroxyvitamin D (S-25-OHD), parathyroid hormone (S-PTH) and bone remodelling markers. Differences among months were observed in calcitropic hormones, bone formation marker, and BMD of the femur and vertebra in a cross-sectional study of early and mid pubertal girls, thus predicting seasonal variation. Vitamin D supplementation increased bone mineral accrual dose-dependently both in the femur and the vertebra of adolescent girls. Bone mineral accrual was 17.2% higher in the femur and 12.5% higher in the vertebra with 10 µg of vitamin D than with placebo, but the effect depended on compliance. The effect of vitamin D on bone was mediated through decreased resorption. Based on the results, a total intake of 15 µg/d appears to be sufficient for adolescent girls. The effect of vitamin D supplementation (5-20 µg/d) on S-25-OHD concentration of elderly women reached a plateau within six weeks. A concentration of 80 nmol/l, which is considered optimal, was not achieved with these dosages. We estimated that a concentration of 60 nmol/l, which is typically seen during summer in Finland, requires a total intake of 24 µg/d of vitamin D in elderly women. Seasonal variation in calcitropic hormones and bone resorption marker, but not in volumetric BMD of the radius or bone formation marker, was noted in healthy men in a prospective study. Vitamin D supplementation increased S-25-OHD, inhibited winter elevation of PTH and decreased bone formation marker, but did not affect BMD during this 6 month study. Adequate intake to avoid the season-related changes was calculated to be 17 µg/d. In summary, vitamin D intake remains inadequate among the target groups of this thesis, as reflected by seasonal variation in calcitropic hormones and bone metabolism. Dietary intake of vitamin D should be increased to achieve at least an adequate vitamin D status (S-25-OHD>50 nmol/l) and possibly an optimal vitamin D status (S-25-OHD>80 nmol/l) throughout the year. This could be accomplished by introducing new vitamin D-fortified foods to the market.