38 resultados para consensus

em Helda - Digital Repository of University of Helsinki


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The purpose of this study is to analyse the development and understanding of the idea of consensus in bilateral dialogues among Anglicans, Lutherans and Roman Catholics. The source material consists of representative dialogue documents from the international, regional and national dialogues from the 1960s until 2006. In general, the dialogue documents argue for agreement/consensus based on commonality or compatibility. Each of the three dialogue processes has specific characteristics and formulates its argument in a unique way. The Lutheran-Roman Catholic dialogue has a particular interest in hermeneutical questions. In the early phases, the documents endeavoured to describe the interpretative principles that would allow the churches to together proclaim the Gospel and to identify the foundation on which the agreement in the church is based. This investigation ended up proposing a notion of basic consensus , which later developed into a form of consensus that seeks to embrace, not to dismiss differences (so-called differentiated consensus ). The Lutheran-Roman Catholic agreement is based on a perspectival understanding of doctrine. The Anglican-Roman Catholic dialogue emphasises the correctness of interpretations. The documents consciously look towards a common future , not the separated past. The dialogue s primary interpretative concept is koinonia. The texts develop a hermeneutics of authoritative teaching that has been described as the rule of communion . The Anglican-Lutheran dialogue is characterised by an instrumental understanding of doctrine. Doctrinal agreement is facilitated by the ideas of coherence, continuity and substantial emphasis in doctrine. The Anglican-Lutheran dialogue proposes a form of sufficient consensus that considers a wide set of doctrinal statements and liturgical practices to determine whether an agreement has been reached to the degree that, although not complete , is sufficient for concrete steps towards unity. Chapter V discusses the current challenges of consensus as an ecumenically viable concept. In this part, I argue that the acceptability of consensus as an ecumenical goal is based not only the understanding of the church but more importantly on the understanding of the nature and function of the doctrine. The understanding of doctrine has undergone significant changes during the time of the ecumenical dialogues. The major shift has been from a modern paradigm towards a postmodern paradigm. I conclude with proposals towards a way to construct a form of consensus that would survive philosophical criticism, would be theologically valid and ecumenically acceptable.

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Austria and Finland are persistently referred to as the “success stories” of post-1945 European history. Notwithstanding their different points of departure, in the course of the Cold War both countries portrayed themselves as small and neutral border-states in the world dictated by superpower politics. By the 1970s, both countries frequently ranked at the top end in various international classifications regarding economic development and well-being in society. This trend continues today. The study takes under scrutiny the concept of consensus which figures centrally in the two national narratives of post-1945 success. Given that the two domestic contexts as such only share few direct links with one another and are more obviously different than similar in terms of their geographical location, historical experiences and politico-cultural traditions, the analogies and variations in the anatomies of the post-1945 “cultures of consensus” provide an interesting topic for a historical comparative and cross-national examination. The main research question concerns the identification and analysis of the conceptual and procedural convergence points of the concepts of the state and consensus. The thesis is divided into six main chapters. After the introduction, the second chapter presents the theoretical framework in more detail by focusing on the key concepts of the study – the state and consensus. Chapter two also introduces the comparative historical and cross-national research angles. Chapter three grounds the key concepts of the state and consensus in the historical contexts of Austria and Finland by discussing the state, the nation and democracy in a longer term comparative perspective. The fourth and fifth chapter present case studies on the two policy fields, the “pillars”, upon which the post-1945 Austrian and Finnish cultures of consensus are argued to have rested. Chapter four deals with neo-corporatist features in the economic policy making and chapter five discusses the building up of domestic consensus regarding the key concepts of neutrality policies in the 1950s and 1960s. The study concludes that it was not consensus as such but the strikingly intense preoccupation with the theme of domestic consensus that cross-cut, in a curiously analogous manner, the policy-making processes studied. The main challenge for the post-1945 architects of Austrian and Finnish cultures of consensus was to find strategies and concepts for consensus-building which would be compatible with the principles of democracy. Discussed at the level of procedures, the most important finding of the study concerns the triangular mechanism of coordination, consultation and cooperation that set into motion and facilitated a new type of search for consensus in both post-war societies. In this triangle, the agency of the state was central, though in varying ways. The new conceptions concerning a small state’s position in the Cold War world also prompted cross-nationally perceivable willingness to reconsider inherited concepts and procedures of the state and the nation. At the same time, the ways of understanding the role of the state and its relation to society remained profoundly different in Austria and Finland and this basic difference was in many ways reflected in the concepts and procedures deployed in the search for consensus and management of domestic conflicts. For more detailed information, please consult the author.

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In this study I consider what kind of perspective on the mind body problem is taken and can be taken by a philosophical position called non-reductive physicalism. Many positions fall under this label. The form of non-reductive physicalism which I discuss is in essential respects the position taken by Donald Davidson (1917-2003) and Georg Henrik von Wright (1916-2003). I defend their positions and discuss the unrecognized similarities between their views. Non-reductive physicalism combines two theses: (a) Everything that exists is physical; (b) Mental phenomena cannot be reduced to the states of the brain. This means that according to non-reductive physicalism the mental aspect of humans (be it a soul, mind, or spirit) is an irreducible part of the human condition. Also Davidson and von Wright claim that, in some important sense, the mental aspect of a human being does not reduce to the physical aspect, that there is a gap between these aspects that cannot be closed. I claim that their arguments for this conclusion are convincing. I also argue that whereas von Wright and Davidson give interesting arguments for the irreducibility of the mental, their physicalism is unwarranted. These philosophers do not give good reasons for believing that reality is thoroughly physical. Notwithstanding the materialistic consensus in the contemporary philosophy of mind the ontology of mind is still an uncharted territory where real breakthroughs are not to be expected until a radically new ontological position is developed. The third main claim of this work is that the problem of mental causation cannot be solved from the Davidsonian - von Wrightian perspective. The problem of mental causation is the problem of how mental phenomena like beliefs can cause physical movements of the body. As I see it, the essential point of non-reductive physicalism - the irreducibility of the mental - and the problem of mental causation are closely related. If mental phenomena do not reduce to causally effective states of the brain, then what justifies the belief that mental phenomena have causal powers? If mental causes do not reduce to physical causes, then how to tell when - or whether - the mental causes in terms of which human actions are explained are actually effective? I argue that this - how to decide when mental causes really are effective - is the real problem of mental causation. The motivation to explore and defend a non-reductive position stems from the belief that reductive physicalism leads to serious ethical problems. My claim is that Davidson's and von Wright's ultimate reason to defend a non-reductive view comes back to their belief that a reductive understanding of human nature would be a narrow and possibly harmful perspective. The final conclusion of my thesis is that von Wright's and Davidson's positions provide a starting point from which the current scientistic philosophy of mind can be critically further explored in the future.

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Workers' theatres in Finland until 1922 The topic of this dissertation is the workers' theatres in Finland before the year 1922. The main question is: why did these amateur theatres within the workers' associations become part of the professional theatre field in the 1910s by getting state subsidy as local theatre institutions? How is it possible that they received this status even after the civil war in 1918 when new professional theatres were founded all over the country? The study also asks, what kind of position did workers' theatres have in the workers' associations and in the workers' movement, what did the Social Democrats and Communists think of theatre and in particular of workers' theatre, and what kind of repertoire did the workers' theatres perform? It is a particular feature of Finland that the professional theatre field was not organised and that the workers’ movement had a relatively strong political position. The study concludes that some workers' theatres were the only steady theatre institutions in their surroundings, and thus functioned as local popular theatres performing to all social groups. Although amateur-based, they started to resemble professional theatres. Even though the Social Democratic Party did not have a specific theatre policy, the leaders of the Party appreciated and supported the workers' theatres as educational institutions and worked for their artistic improvement. The workers' theatres were also largely approved of and seen as people's theatres thought to unite and educate the nation and the working class. This reveals the need for national consensus, in the 1910s against the Russian government who worked to dissolve the autonomous position of the Finnish state, and after the civil war (1918) against the threat of a communist revolution. A wave of agitating proletarian theatre was felt in Finland in the early 1920s but it was marginalised by the large anti-communist majority.

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The aim of the research is to interpret the professional culture of Finnish university-educated foresters in historical perspective. The main material of this research consists of biographical interviews, altogether 226 life stories of Finnish foresters, as well as foresters private photograph collections and articles in forest students' magazines. This study is the first published Ph. D. dissertation of a large oral history project "Forestry Professions in a Changing Society" 1999 2002 collected by The Finnish Forest History Society, the University of Helsinki (Ethnology) and The Finnish Forest Museum Lusto. The forester education was organized in the Evo Forest Institute 1862 1908, at the University of Helsinki since 1908 and additionally at the University of Joensuu since 1982. At first all the vacancies were in the service of the Board of Forestry, but during the 20th century the working opportunities of foresters significantly expanded, even outside the traditional areas of forestry or abroad. At the same time the whole area of Finnish forestry had integrated more versatile values concerning the forests and their use. The male-dominated profession gained its first female members already in the 1920s, and the number of female students rose gradually from the 1970s onwards. In the 1990s almost half of the new forest students were women. The content of both work and education of Finnish forest professionals has faced huge changes during the 19th and 20th centuries. Despite this however, there has been a long-term vision of a firm profession based on joint experiences, shared memories and the common task of foresters in the Finnish forestry. The feeling of togetherness the forester spirit which was created in a tight-knit student group which kept in touch also later as professionals was needed to make the work possible. Through foresters' own attitudes and narratives of themselves, the study is focused on forest professionalism as a cultural process of successive generations of foresters. How have foresters socialized themselves into their profession? How has forest professionalism been maintained? What is the meaning of joint experiences and shared memories in the profession? By studying the manifestations of a culture it is possible to interpret the culture itself. There seems to be an astounding consensus of opinion concerning forest professionalism in the oral, visual and written stories of foresters. Even if all the individuals and some separate groups, such as female foresters and the younger generation of foresters, did not always share the same experiences, the vision of forest professionalism was collectively recognized and often even approved. The shared idea of "a real forest professionalism" is like a model narrative, a point of comparison, which is needed while looking for one s own professional identity.

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In the future the number of the disabled drivers requiring a special evaluation of their driving ability will increase due to the ageing population, as well as the progress of adaptive technology. This places pressure on the development of the driving evaluation system. Despite quite intensive research there is still no consensus concerning what is the factual situation in a driver evaluation (methodology), which measures should be included in an evaluation (methods), and how an evaluation has to be carried out (practise). In order to find answers to these questions we carried out empirical studies, and simultaneously elaborated upon a conceptual model for driving and a driving evaluation. The findings of empirical studies can be condensed into the following points: 1) A driving ability defined by the on-road driving test is associated with different laboratory measures depending on the study groups. Faults in the laboratory tests predicted faults in the on-road driving test in the novice group, whereas slowness in the laboratory predicted driving faults in the experienced drivers group. 2) The Parkinson study clearly showed that even an experienced clinician cannot reliably accomplish an evaluation of a disabled person’s driving ability without collaboration with other specialists. 3) The main finding of the stroke study was that the use of a multidisciplinary team as a source of information harmonises the specialists’ evaluations. 4) The patient studies demonstrated that the disabled persons themselves, as well as their spouses, are as a rule not reliable evaluators. 5) From the safety point of view, perceptible operations with the control devices are not crucial, but correct mental actions which the driver carries out with the help of the control devices are of greatest importance. 6) Personality factors including higher-order needs and motives, attitudes and a degree of self-awareness, particularly a sense of illness, are decisive when evaluating a disabled person’s driving ability. Personality is also the main source of resources concerning compensations for lower-order physical deficiencies and restrictions. From work with the conceptual model we drew the following methodological conclusions: First, the driver has to be considered as a holistic subject of the activity, as a multilevel hierarchically organised system of an organism, a temperament, an individuality, and a personality where the personality is the leading subsystem from the standpoint of safety. Second, driving as a human form of a sociopractical activity, is also a hierarchically organised dynamic system. Third, in an evaluation of driving ability it is a question of matching these two hierarchically organised structures: a subject of an activity and a proper activity. Fourth, an evaluation has to be person centred but not disease-, function- or method centred. On the basis of our study a multidisciplinary team (practitioner, driving school teacher, psychologist, occupational therapist) is recommended for use in demanding driver evaluations. Primary in a driver’s evaluations is a coherent conceptual model while concrete methods of evaluations may vary. However, the on-road test must always be performed if possible.

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The crucial questions that define democracy relate to its depth and width: who can participate in decision making and what kind of things can be commonly decided? Theories deeper than representative democracy emphasize discussion, in which by evaluating justifications it is possible to achieve consensus in ideal situation. The aim of my research is to develop tools for promoting the participation of third graders in decision making in the classroom. In addition I study the development of depth and width of democracy in the classroom, the development of skills and competencies in the decision making and the challenges of the project. My research method is participative action research. I collected my data between October 2007 and March 2008. I used videos and observation diaries as my primary data. Additional data consisted of the interviews of the students, the conversations between the adults and the material produced by the teacher. Since we discussed the matters students had highlighted in specific lessons, my analysis proceeds according to these lessons constructing a general view of the process. The width and depth of classroom democracy are difficult to define. Though the system we had created enabled third graders to discuss matters they found important the participation was unequal: some of the students couldn’t among other things give justifications for their opinions. This poses challenges for models that emphasize deliberation since these theories presuppose that everyone has concordant competencies. But then again only critical citizens who are able to make justifications and to evaluate them are able to oppose indoctrination. This makes teaching these competencies justified. Different decision making procedures define the classroom democracy. Deliberation doesn’t necessarily provide deeper information about the preferences of the participants than mere voting. But then again voting doesn’t express the reasons which support one’s preferences. Structured conversation can equalize the time used for every participant’s opinions, but doesn’t solve the challenge of unequal competencies. Children’s suggestion box diversified the possibilities to participate, and also the silent ones used it during the research. The asymmetry in deliberation might also be caused by the social structure of the students. Teacher’s directing and participation encouraging role in deliberation was significant. Diversifying the participation by different roles could equalize the asymmetry in participation.

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Aims: The aims of this study were 1) to identify and describe health economic studies that have used quality-adjusted life years (QALYs) based on actual measurements of patients' health-related quality of life (HRQoL); 2) to test the feasibility of routine collection of health-related quality of life (HRQoL) data as an indicator of effectiveness of secondary health care; and 3) to establish and compare the cost-utility of three large-volume surgical procedures in a real-world setting in the Helsinki University Central Hospital, a large referral hospital providing secondary and tertiary health-care services for a population of approximately 1.4 million. Patients and methods: So as to identify studies that have used QALYs as an outcome measure, a systematic search of the literature was performed using the Medline, Embase, CINAHL, SCI and Cochrane Library electronic databases. Initial screening of the identified articles involved two reviewers independently reading the abstracts; the full-text articles were also evaluated independently by two reviewers, with a third reviewer used in cases where the two reviewers could not agree a consensus on which articles should be included. The feasibility of routinely evaluating the cost-effectiveness of secondary health care was tested by setting up a system for collecting HRQoL data on approximately 4 900 patients' HRQoL before and after operative treatments performed in the hospital. The HRQoL data used as an indicator of treatment effectiveness was combined with diagnostic and financial indicators routinely collected in the hospital. To compare the cost-effectiveness of three surgical interventions, 712 patients admitted for routine operative treatment completed the 15D HRQoL questionnaire before and also 3-12 months after the operation. QALYs were calculated using the obtained utility data and expected remaining life years of the patients. Direct hospital costs were obtained from the clinical patient administration database of the hospital and a cost-utility analysis was performed from the perspective of the provider of secondary health care services. Main results: The systematic review (Study I) showed that although QALYs gained are considered an important measure of the effectiveness of health care, the number of studies in which QALYs are based on actual measurements of patients' HRQoL is still fairly limited. Of the reviewed full-text articles, only 70 reported QALYs based on actual before after measurements using a valid HRQoL instrument. Collection of simple cost-effectiveness data in secondary health care is feasible and could easily be expanded and performed on a routine basis (Study II). It allows meaningful comparisons between various treatments and provides a means for allocating limited health care resources. The cost per QALY gained was 2 770 for cervical operations and 1 740 for lumbar operations. In cases where surgery was delayed the cost per QALY was doubled (Study III). The cost per QALY ranges between subgroups in cataract surgery (Study IV). The cost per QALY gained was 5 130 for patients having both eyes operated on and 8 210 for patients with only one eye operated on during the 6-month follow-up. In patients whose first eye had been operated on previous to the study period, the mean HRQoL deteriorated after surgery, thus precluding the establishment of the cost per QALY. In arthroplasty patients (Study V) the mean cost per QALY gained in a one-year period was 6 710 for primary hip replacement, 52 270 for revision hip replacement, and 14 000 for primary knee replacement. Conclusions: Although the importance of cost-utility analyses has during recent years been stressed, there are only a limited number of studies in which the evaluation is based on patients own assessment of the treatment effectiveness. Most of the cost-effectiveness and cost-utility analyses are based on modeling that employs expert opinion regarding the outcome of treatment, not on patient-derived assessments. Routine collection of effectiveness information from patients entering treatment in secondary health care turned out to be easy enough and did not, for instance, require additional personnel on the wards in which the study was executed. The mean patient response rate was more than 70 %, suggesting that patients were happy to participate and appreciated the fact that the hospital showed an interest in their well-being even after the actual treatment episode had ended. Spinal surgery leads to a statistically significant and clinically important improvement in HRQoL. The cost per QALY gained was reasonable, at less than half of that observed for instance for hip replacement surgery. However, prolonged waiting for an operation approximately doubled the cost per QALY gained from the surgical intervention. The mean utility gain following routine cataract surgery in a real world setting was relatively small and confined mostly to patients who had had both eyes operated on. The cost of cataract surgery per QALY gained was higher than previously reported and was associated with considerable degree of uncertainty. Hip and knee replacement both improve HRQoL. The cost per QALY gained from knee replacement is two-fold compared to hip replacement. Cost-utility results from the three studied specialties showed that there is great variation in the cost-utility of surgical interventions performed in a real-world setting even when only common, widely accepted interventions are considered. However, the cost per QALY of all the studied interventions, except for revision hip arthroplasty, was well below 50 000, this figure being sometimes cited in the literature as a threshold level for the cost-effectiveness of an intervention. Based on the present study it may be concluded that routine evaluation of the cost-utility of secondary health care is feasible and produces information essential for a rational and balanced allocation of scarce health care resources.

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Although the principle of equal access to medically justified treatment has been promoted by official health policies in many Western health care systems, practices do not completely meet policy targets. Waiting times for elective surgery vary between patient groups and regions, and growing problems in the availability of services threaten equal access to treatment. Waiting times have come to the attention of decision-makers, and several policy initiatives have been introduced to ensure the availability of care within a reasonable time. In Finland, for example, the treatment guarantee came into force in 2005. However, no consensus exists on optimal waiting time for different patient groups. The purpose of this multi-centre randomized controlled trial was to analyse health-related quality of life, pain and physical function in total hip or knee replacement patients during the waiting time and to evaluate whether the waiting time is associated with patients health outcomes at admission. This study also assessed whether the length of waiting time is associated with social and health services utilization in patients awaiting total hip or knee replacement. In addition, patients health-related quality of life was compared with that of the general population. Consecutive patients with a need for a primary total hip or knee replacement due to osteoarthritis were placed on the waiting list between August 2002 and November 2003. Patients were randomly assigned to a short waiting time (maximum 3 months) or a non-fixed waiting time (waiting time not fixed in advance, instead the patient followed the hospitals routine practice). Patients health-related quality of life was measured upon being placed on the waiting list and again at hospital admission using the generic 15D instrument. Pain and physical function were evaluated using the self-report Harris Hip Score for hip patients and a scale modified from the Knee Society Clinical Rating System for knee patients. Utilization measures were the use of home health care, rehabilitation and social services, physician visits and inpatient care. Health and social services use was low in both waiting time groups. The most common services used while waiting were rehabilitation services and informal care, including unpaid care provided by relatives, neighbours and volunteers. Although patients suffered from clear restrictions in usual activities and physical functioning, they seemed primarily to lean on informal care and personal networks instead of professional care. While longer waiting time did not result in poorer health-related quality of life at admission and use of services during the waiting time was similar to that at the time of placement on the list, there is likely to be higher costs of waiting by people who wait longer simply because they are using services for a longer period. In economic terms, this would represent a negative impact of waiting. Only a few reports have been published of the health-related quality of life of patients awaiting total hip or knee replacement. These findings demonstrate that, in addition to physical dimensions of health, patients suffered from restrictions in psychological well-being such as depression, distress and reduced vitality. This raises the question of how to support patients who suffer from psychological distress during the waiting time and how to develop strategies to improve patients initiatives to reduce symptoms and the burden of waiting. Key words: waiting time, total hip replacement, total knee replacement, health-related quality of life, randomized controlled trial, outcome assessment, social service, utilization of health services

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In complement activation, Factor H (FH) and C4b-binding protein (C4bp) are the key regulators that prevent the complement cascade from attacking host tissues. Some bacteria may bind and deposit these regulators on their own surfaces and thus provide themselves with an efficient means to avoid complement activation. In consequence, bacteria resist complement-mediated lysis and opsonin-dependent phagocytosis. This study has demonstrated that Y. enterocolitica, similar to many other pathogens, recruits both FH and C4bp to its surface to ensure protection against the complement-mediated killing. YadA and Ail, the most crucial serum resistance factors of Y.enterocolitica, mediate the binding of FH and C4bp. FH - YadA interaction involves multiple higher structural motifs on the YadA stalk and the short consensus repeats (SCRs) of the entire polypeptide chain of FH. The Ail binding site on FH has been located to SCRs 6 and 7. The binding site for FH on Ail, however, remains undetermined. Both YadA- and Ail-bound regulators display full cofactor activity for FI-mediated cleavage of C3b/C4b. FH/C4bp-binding characteristics do, however, differ between YadA and Ail. In addition, Ail captures the regulators only in the absence of blocking lipopolysaccharide O-antigen and outer core, whereas YadA binds FH/C4bp independent of the presence of other surface factors Independent of mode of binding, however, YadA and Ail provide Y. enterocolitica a means to avoid complement-mediated lysis, enhancing chances for the bacteria to survive in the host during various phases of infection.

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Populations in developed countries are ageing fast. The elderly have the greatest incidence of de-mentia, and thus the increase in the number of demented individuals, increases the immediate costs for the governments concerning healthcare and hospital treatment. Attention is being paid to disorders behind cognitive impairment with behavioural and psychological symptoms, which are enormous contributors to the hospital care required for the elderly. The highest dreams are in prevention; however, before discovering the tools for preventing dementia, the pathogenesis behind dementia disorders needs to be understood. Dementia with Lewy bodies (DLB), a relatively recently discovered dementia disorder compared to Alzheimer’s disease (AD), is estimated to account for up to one third of primary degenerative dementia, thus being the second most common cause of dementia in the elderly. Nevertheless, the impact of neuropathological and genetic findings on the clinical syndrome of DLB is not fully established. In this present series of studies, the frequency of neuropathological findings of DLB and its relation to the clinical findings was evaluated in a cohort of subjects with primary degenerative dementia and in a population-based prospective cohort study of individuals aged 85 years or older. α-synuclein (αS) immunoreactive pathology classifiable according to the DLB consensus criteria was found in one fourth of the primary degenerative dementia subjects. In the population-based study, the corresponding figure was one third of the population, 38% of the demented and one fifth of the non-demented very elderly Finns. However, in spite of the frequent discovery of αS pathology, its association with the clinical symptoms was quite poor. Indeed, the common clinical features of DLB, hypokinesia and visual hallucinations, associated better with the severe neurofibrillary AD-type pathology than with the extensive (diffuse neocortical) αS pathology when both types of pathology were taken into account. The severity of the neurofibrillary AD-type pathology (Braak stage) associated with the extent of αS pathology in the brain. In addition, the genetic study showed an interaction between tau and αS; common variation in the αS gene (SNCA) associated significantly with the severity of the neurofibrillary AD-type pathology and nominally significantly with the extensive αS pathology. Further, the relevance and temporal course of the substantia nigra (SN) degeneration and of the spinal cord αS pathology were studied in relation to αS pathology in the brain. The linear association between the extent of αS pathology in the brain and the neuron loss in SN suggests that in DLB the degeneration of SN proceeds as the αS pathology extends from SN to the neocortex instead of early destruction of SN seen in Parkinson’s disease (PD). Furthermore, the extent of αS pathology in the brain associated with the severity of αS pathology in the thoracic and sacral autonomic nuclei of the spinal cord. The thoracic αS pathology was more common and more severe compared to sacral cord, suggesting that the progress of αS pathology proceeds downwards from the brainstem towards the sacral spinal cord.

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The particles of Potato virus A (PVA; genus Potyvirus) are helically constructed filaments that contain multiple copies of a single type of coat-protein (CP) subunit and a single copy of genome-linked protein (VPg), attached to one end of the virion. Examination of negatively-stained virions by electron microscopy revealed flexuous, rod-shaped particles with no obvious terminal structures. It is known that particles of several filamentous plant viruses incorporate additional minor protein components, forming stable complexes that mediate particle disassembly, movement or transmission by insect vectors. The first objective of this work was to study the interaction of PVA movement-associated proteins with virus particles and how these interactions contribute to the morphology and function of the virus particles. Purified particles of PVA were examined by atomic force microscopy (AFM) and immuno-gold electron microscopy. A protrusion was found at one end of some of the potyvirus particles, associated with the 5' end of the viral RNA. The tip contained two virus-encoded proteins, the genome-linked protein (VPg) and the helper-component proteinase (HC-Pro). Both are required for cell-to-cell movement of the virus. Biochemical and electron microscopy studies of purified PVA samples also revealed the presence of another protein required for cell-to-cell movement the cylindrical inclusion protein (CI), which is also an RNA helicase/ATPase. Centrifugation through a 5-40% sucrose gradient separated virus particles with no detectable CI to a fraction that remained in the gradient, from the CI-associated particles that went to the pellet. Both types of particles were infectious. AFM and translation experiments demonstrated that when the viral CI was not present in the sample, PVA virions had a beads-on-a-string phenotype, and RNA within the virus particles was more accessible to translation. The second objective of this work was to study phosphorylation of PVA movement-associated and structural proteins (CP and VPg) in vitro and, if possible, in vivo. PVA virion structural protein CP is necessary for virus cell-to-cell movement. The tobacco protein kinase CK2 was identified as a kinase phosphorylating PVA CP. A major site of CK2 phosphorylation in PVA CP was identified as a single threonine within a CK2 consensus sequence. Amino acid substitutions affecting the CK2 consensus sequence in CP resulted in viruses that were defective in cell-to-cell and long-distance movement. The CK2 regulation of virion assembly and cell-to-cell movement by phosphorylation of CP was possibly due to the inhibition of CP binding to viral RNA. Four putative phosphorylation sites were identified from an in vitro phosphorylated recombinant VPg. All four were mutated and the spread of mutant viruses in two different host plants was studied. Two putative phosphorylation site mutants (Thr45 and Thr49) had phenotypes identical to that of a wild type (WT) virus infection in both Nicotiana benthamiana and N. tabacum plants. The other two mutant viruses (Thr132/Ser133 and Thr168) showed different phenotypes with increased or decreased accumulation rates, respectively, in inoculated and the first two systemically infected leaves of N. benthamiana. The same mutants were occasionally restricted to single cells in N. tabacum plants, suggesting the importance of these amino acids in the PVA infection cycle in N. tabacum.

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Wireless technologies are continuously evolving. Second generation cellular networks have gained worldwide acceptance. Wireless LANs are commonly deployed in corporations or university campuses, and their diffusion in public hotspots is growing. Third generation cellular systems are yet to affirm everywhere; still, there is an impressive amount of research ongoing for deploying beyond 3G systems. These new wireless technologies combine the characteristics of WLAN based and cellular networks to provide increased bandwidth. The common direction where all the efforts in wireless technologies are headed is towards an IP-based communication. Telephony services have been the killer application for cellular systems; their evolution to packet-switched networks is a natural path. Effective IP telephony signaling protocols, such as the Session Initiation Protocol (SIP) and the H 323 protocol are needed to establish IP-based telephony sessions. However, IP telephony is just one service example of IP-based communication. IP-based multimedia sessions are expected to become popular and offer a wider range of communication capabilities than pure telephony. In order to conjoin the advances of the future wireless technologies with the potential of IP-based multimedia communication, the next step would be to obtain ubiquitous communication capabilities. According to this vision, people must be able to communicate also when no support from an infrastructured network is available, needed or desired. In order to achieve ubiquitous communication, end devices must integrate all the capabilities necessary for IP-based distributed and decentralized communication. Such capabilities are currently missing. For example, it is not possible to utilize native IP telephony signaling protocols in a totally decentralized way. This dissertation presents a solution for deploying the SIP protocol in a decentralized fashion without support of infrastructure servers. The proposed solution is mainly designed to fit the needs of decentralized mobile environments, and can be applied to small scale ad-hoc networks or also bigger networks with hundreds of nodes. A framework allowing discovery of SIP users in ad-hoc networks and the establishment of SIP sessions among them, in a fully distributed and secure way, is described and evaluated. Security support allows ad-hoc users to authenticate the sender of a message, and to verify the integrity of a received message. The distributed session management framework has been extended in order to achieve interoperability with the Internet, and the native Internet applications. With limited extensions to the SIP protocol, we have designed and experimentally validated a SIP gateway allowing SIP signaling between ad-hoc networks with private addressing space and native SIP applications in the Internet. The design is completed by an application level relay that permits instant messaging sessions to be established in heterogeneous environments. The resulting framework constitutes a flexible and effective approach for the pervasive deployment of real time applications.

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The present study examines empirically the inflation dynamics of the euro area. The focus of the analysis is on the role of expectations in the inflation process. In six articles we relax rationality assumption and proxy expectations directly using OECD forecasts or Consensus Economics survey data. In the first four articles we estimate alternative Phillips curve specifications and find evidence that inflation cannot instantaneously adjust to changes in expectations. A possible departure of expectations from rationality seems not to be powerful enough to totally explain the persistence of euro area inflation in the New Keynesian framework. When expectations are measured directly, the purely forward-looking New Keynesian Phillips curve is outperformed by the hybrid Phillips curve with an additional lagged inflation term and the New Classical Phillips curve with a lagged expectations term. The results suggest that the euro area inflation process has become more forward-looking in the recent years of low and stable inflation. Moreover, in low inflation countries, the inflation dynamics have been more forward-looking already since the late 1970s. We find evidence of substantial heterogeneity of inflation dynamics across the euro area countries. Real time data analysis suggests that in the euro area real time information matters most in the expectations term in the Phillips curve and that the balance of expectations formation is more forward- than backward-looking. Vector autoregressive (VAR) models of actual inflation, inflation expectations and the output gap are estimated in the last two articles.The VAR analysis indicates that inflation expectations, which are relatively persistent, have a significant effect on output. However,expectations seem to react to changes in both output and actual inflation, especially in the medium term. Overall, this study suggests that expectations play a central role in inflation dynamics, which should be taken into account in conducting monetary policy.

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Understanding the overwhelming diversity of life calls for complex organisational schemes. The field of systematics may thus be seen as the cornerstone of evolutionary biology. In the last few decades, systematics has been rejuvenated through the introduction of molecular methods such as DNA barcoding and multi-gene phylogenetic approaches. These methods may shed new light on established taxonomic ideas and problems. For example, the classification of ants has aroused much debate due to reinterpretation of morphological characters or contradictions between molecular data and morphology. Only in the last few years a consensus was reached regarding the phylogeny of ant subfamilies. However, the situation remains deplorable for lower taxonomic ranks such as subfamilies, tribes and genera. This thesis describes the systematics and evolution of the Holarctic ant genus Myrmica and the tribe to which it belongs, Myrmicini. Using barcoding, molecular-phylogenetic data and divergence time estimations, it addresses questions regarding the taxonomy, morphology and biogeography of this group. Furthermore, the interrelationships between socially parasitic Myrmica species and their hosts (other species in the genus) were inferred. The phylogeny suggests that social parasitism evolved several times in Myrmica. Finally, this thesis investigated whether coevolution shaped the phylogeny of socially parasitic Maculinea butterflies that live inside Myrmica colonies. No evidence was found for coevolution.