14 resultados para crossing over

em Helda - Digital Repository of University of Helsinki


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During the last decades there has been a global shift in forest management from a focus solely on timber management to ecosystem management that endorses all aspects of forest functions: ecological, economic and social. This has resulted in a shift in paradigm from sustained yield to sustained diversity of values, goods and benefits obtained at the same time, introducing new temporal and spatial scales into forest resource management. The purpose of the present dissertation was to develop methods that would enable spatial and temporal scales to be introduced into the storage, processing, access and utilization of forest resource data. The methods developed are based on a conceptual view of a forest as a hierarchically nested collection of objects that can have a dynamically changing set of attributes. The temporal aspect of the methods consists of lifetime management for the objects and their attributes and of a temporal succession linking the objects together. Development of the forest resource data processing method concentrated on the extensibility and configurability of the data content and model calculations, allowing for a diverse set of processing operations to be executed using the same framework. The contribution of this dissertation to the utilisation of multi-scale forest resource data lies in the development of a reference data generation method to support forest inventory methods in approaching single-tree resolution.

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In Finland, peat harvesting sites are utilized down almost to the mineral soil. In this situation the properties of mineral subsoil are likely to have considerable influence on the suitability for the various after-use forms. The aims of this study were to recognize the chemical and physical properties of mineral subsoils possibly limiting the after-use of cut-over peatlands, to define a minimum practice for mineral subsoil studies and to describe the role of different geological areas. The future percentages of the different after-use forms were predicted, which made it possible to predict also carbon accumulation in this future situation. Mineral subsoils of 54 different peat production areas were studied. Their general features and grain size distribution was analysed. Other general items studied were pH, electrical conductivity, organic matter, water soluble nutrients (P, NO3-N, NH4-N, S and Fe) and exchangeable nutrients (Ca, Mg and K). In some cases also other elements were analysed. In an additional case study carbon accumulation effectiveness before the intervention was evaluated on three sites in Oulu area (representing sites typically considered for peat production). Areas with relatively sulphur rich mineral subsoil and pool-forming areas with very fine and compact mineral subsoil together covered approximately 1/5 of all areas. These areas were unsuitable for commercial use. They were recommended for example for mire regeneration. Another approximate 1/5 of the areas included very coarse or very fine sediments. Commercial use of these areas would demand special techniques - like using the remaining peat layer for compensating properties missing from the mineral subsoil. One after-use form was seldom suitable for one whole released peat production area. Three typical distribution patterns (models) of different mineral subsoils within individual peatlands were found. 57 % of studied cut-over peatlands were well suited for forestry. In a conservative calculation 26% of the areas were clearly suitable for agriculture, horticulture or energy crop production. If till without large boulders was included, the percentage of areas suitable to field crop production would be 42 %. 9-14 % of all areas were well suitable for mire regeneration or bird sanctuaries, but all areas were considered possible for mire regeneration with correct techniques. Also another 11 % was recommended for mire regeneration to avoid disturbing the mineral subsoil, so total 20-25 % of the areas would be used for rewetting. High sulphur concentrations and acidity were typical to the areas below the highest shoreline of the ancient Litorina sea and Lake Ladoga Bothnian Bay zone. Also differences related to nutrition were detected. In coarse sediments natural nutrient concentration was clearly higher in Lake Ladoga Bothnian Bay zone and in the areas of Svecokarelian schists and gneisses, than in Granitoid area of central Finland and in Archaean gneiss areas. Based on this study the recommended minimum analysis for after-use planning was for pH, sulphur content and fine material (<0.06 mm) percentage. Nutrition capacity could be analysed using the natural concentrations of calcium, magnesium and potassium. Carbon accumulation scenarios were developed based on the land-use predictions. These scenarios were calculated for areas in peat production and the areas released from peat production (59300 ha + 15 671 ha). Carbon accumulation of the scenarios varied between 0.074 and 0.152 million t C a-1. In the three peatlands considered for peat production the long term carbon accumulation rates varied between 13 and 24 g C m-2 a-1. The natural annual carbon accumulation had been decreasing towards the time of possible intervention.

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Territoriality is a central issue in indigenous peoples struggles. The territorial struggles involve struggles over the control of natural resources and over political participation and representation, but also over the perception of territorial rights and the symbolic representation of the territory. These struggles are carried through both in material and symbolic ways through recurring to different discourses and representations that provide legitimation for the territorial claims of the group. The study is located in the Northern Autonomous Atlantic Region of Nicaragua. The study concerns the territorial strategies, conceptions and practices of the indigenous people and other actors. Territorial conflicts exist between the autonomous region and the central government of Nicaragua, between mestizo settlers and indigenous people, between different indigenous groups, and between these and development agents such as conservation projects. The study focuses on how territorial discourses and representations are used to legitimate territorial control. Environmental, historical and cartographical discourses are the most important discourses recurred to. The influence of discourses and representations on the territorial practices and policies of the different actors, the links between the local struggles and global processes, and the broader structural factors impacting on the territorial struggles are also analysed. Among the structural factors are the problems related to land tenure and management and the use of natural resources, the advance of the agricultural frontier, the institutional weaknesses of the central and regional governments and the legislative processes. The territorial discourses are both recurred to in a strategic way and also grounded in local ideals and practices. The discourses have produced real effects for example in legislation, land tenure systems, political representation and environmental practices. Although the use of discourses and representations are an important power tool in territorial struggles, territorial control cannot be effectively accomplished merely through representing territorial claims in a legitimate way or through reforming legislation, as the conflicts are also largely a result of structural factors affecting the region. The fieldwork was carried out during a total of twelve months between 2000 and 2002. The research methods used were semi-structured interviews, participant observation and participatory research methods. A broad range of literary sources were also used to collect data. The study is located within the field of critical political geography with a discursive political ecology approach. It can be called a critical realist approach to the discursive analysis of indigenous territoriality.

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This Ph.D. thesis Participation or Further Exclusion? Contestations over Forest Conservation and Control in the East Usambara Mountains, Tanzania describes and analyses the shift in the prevailing discourse of forest and biodiversity conservation policies and strategies towards more participatory approaches in Tanzania, and the changes in the practises of resource control. I explore the scope for and limits to the different actors and groups who are considered to form the community, to participate in resource control, in a specific historical and socio-economic context. I analyse whether, how and to which extent the targets of such participatory conservation interventions have been able to affect the formal rules and practices of resource control, and explore their different responses and discursive and other strategies in relation to conservation efforts. I approach the problematic through exploring certain participatory conservation interventions and related negotiations between the local farmers, government officials and the external actors in the case of two protected forest reserves in the southern part of the East Usambaras, Tanzania. The study area belongs to the Eastern Arc Mountains that are valued globally and nationally for their high level of biodiversity and number of endemic and near endemic species. The theoretical approach draws from theorising on power, participation and conservation in anthropology of development and post-structuralist political ecology. The material was collected in three stages between 2003 and 2008 by using an ethnographic approach. I interviewed and observed the actors and their resource use and control practices at the local level, including the representatives of the villagers living close to the protected forests and the conservation agency, but also followed the selected processes and engaged with the non-local agencies involved in the conservation efforts in the East Usambaras. In addition, the more recent processes of change and the actors strategies in resource control were contextualised against the social and environmental history of the study area and the evolvement of institutions of natural resource control. My findings indicate that the discourse of participation that has emerged in global conservation policy debate within the past three decades, and is being institutionalised in the national policies in many countries, including Tanzania, has shaped the practices of forest conservation in the East Usambaras, although in a fragmented and uneven way. Instrumental interpretation of participation, in which it is to serve the goals of improving the control of the forest and making it more acceptable and efficient, has prevailed among the governmental actors and conservation organisations. Yet, there is variation between the different projects and actors promoting participatory conservation regarding the goals and means of participation, e.g. to which extent the local people are to be involved in decision-making. The actors representing communities also have their diverse agendas, understandings and experiences regarding the rationality, outcomes and benefits of being involved in forest control, making the practices of control fluid. The elements of the exclusive conservation thinking and practices co-exist with the more recent participatory processes, and continue to shape the understandings and strategies of the actors involved in resource control. The ideas and narratives of the different discourses are reproduced and selectively used by the parties involved. The idea of forest conservation is not resisted as such by most of the actors at local level, quite the opposite. However, the strict regulations and rules governing access to resources, such as valuable timber species, continue to be disputed by many. Furthermore, the history of control, such as past injustices related to conservation and unfulfilled promises, undermines the participation of certain social groups in resource control and benefit sharing. This also creates controversies in the practices of conservation, and fuels conflicts regarding the establishment of new protected areas. In spite of this, the fact that the representatives of the communities have been invited to the arenas where information is shared, and principles and conditions of forest control and benefit sharing are discussed and partly decided upon, has created expectations among the participants, and opened up opportunities for some of the local actors to enhance their own, and sometimes wider interests in relation to resource control and the related benefits. The local actors experiences of the previous government and other interventions strongly affect how they position themselves in relation to conservation interventions, and their responses and strategies. However, my findings also suggest, in a similar way to research conducted in some other protected areas, that the benefits of participation in conservation and resource control tend to accrue unevenly between different groups of local people, e.g. due to unequal access to information and differences in their initial resources and social position.

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Microneurovascular free muscle transfer with cross-over nerve grafts in facial reanimation Loss of facial symmetry and mimetic function as seen in facial paralysis has an enormous impact on the psychosocial conditions of the patients. Patients with severe long-term facial paralysis are often reanimated with a two-stage procedure combining cross-facial nerve grafting, and 6 to 8 months later with microneurovascular (MNV) muscle transfer. In this thesis, we recorded the long-term results of MNV surgery in facial paralysis and observed the possible contributing factors to final functional and aesthetic outcome after this procedure. Twenty-seven out of forty patients operated on were interviewed, and the functional outcome was graded. Magnetic resonance imaging (MRI) of MNV muscle flaps was done, and nerve graft samples (n=37) were obtained in second stage of the operation and muscle biopsies (n=18) were taken during secondary operations.. The structure of MNV muscles and nerve grafts was evaluated using histological and immunohistochemical methods ( Ki-67, anti-myosin fast, S-100, NF-200, CD-31, p75NGFR, VEGF, Flt-1, Flk-1). Statistical analysis was performed. In our studies, we found that almost two-thirds of the patients achieved good result in facial reanimation. The longer the follow-up time after muscle transfer the weaker was the muscle function. A majority of the patients (78%) defined their quality of life improved after surgery. In MRI study, the free MNV flaps were significantly smaller than originally. A correlation was found between good functional outcome and normal muscle structure in MRI. In muscle biopsies, the mean muscle fiber diameter was diminished to 40% compared to control values. Proliferative activity of satellite cells was seen in 60% of the samples and it tended to decline with an increase of follow-up time. All samples showed intramuscular innervation. Severe muscle atrophy correlated with prolonged intraoperative ischaemia. The good long-term functional outcome correlated with dominance of fast fibers in muscle grafts. In nerve grafts, the mean number of viable axons amounted to 38% of that in control samples. The grafted nerves characterized by fibrosis and regenerated axons were thinner than in control samples although they were well vascularized. A longer time between cross facial nerve grafting and biopsy sampling correlated with a higher number of viable axons. P75Nerve Growth Factor Receptor (p75NGFR) was expressed in every nerve graft sample. The expression of p75NGFR was lower in older than in younger patients. A high expression of p75NGFR was often seen with better function of the transplanted muscle. In grafted nerve Vascular Endothelial Growth Factor (VEGF) and its receptors were expressed in nervous tissue. In conclusion, most of the patients achieved good result in facial reanimation and were satisfied with the functional outcome. The mimic function was poorer in patients with longer follow-up time. MRI can be used to evaluate the structure of the microneurovascular muscle flaps. Regeneration of the muscle flaps was still going on many years after the transplantation and reinnervation was seen in all muscle samples. Grafted nerves were characterized by fibrosis and fewer, thinner axons compared to control nerves although they were well vascularized. P75NGFR and VEGF were expressed in human nerve grafts with higher intensity than in control nerves which is described for the first time.

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Rheumatoid arthritis (RA) patients have premature mortality. Contrary to the general population, mortality in RA has not declined over time. This study aimed to evaluate determinants of mortality in RA by examining causes of death (CoDs) over time, accuracy of CoD diagnoses, and contribution of RA medication to CoDs. This study further evaluated detection rate of reactive systemic amyloid A amyloidosis, which is an important contributor to RA mortality. CoDs were examined in 960 RA patients between 1971 and 1991 (Study population A) and in 369 RA patients autopsied from 1952 to 1991, with non-RA patients serving as the reference cases (Study population B). In Study population B, CoDs by the clinician before autopsy were compared to those by the pathologist at autopsy to study accuracy of CoD diagnoses. In Study population B, autopsy tissue samples were re-examined systematically for amyloidosis (90% of patients) and clinical data for RA patients was studied from 1973. RA patients died most frequently of cardiovascular diseases (CVDs), infections, and RA. RA deaths declined over time. Coronary deaths showed no major change in Study population A, but, in Study population B, coronary deaths in RA patients increased from 1952 to 1991, while non-RA cases had a decrease in coronary deaths starting in the 1970s. Between CoD diagnoses by the clinician and those by the pathologist, RA patients had lower agreement than non-RA cases regarding cardiovascular (Kappa reliability measure: 0.31 vs. 0.51) and coronary deaths (0.33 vs. 0.46). Use of disease modifying anti-rheumatic drugs was not associated with any CoD. In RA patients, re-examination of autopsy tissue samples doubled the prevalence of amyloid compared with the original autopsy: from 18% to 30%. In the amyloid-positive RA patients, amyloidosis was diagnosed before autopsy in only 37%; and they had higher inflammatory levels and longer duration of RA than amyloid-negative RA patients. Of the RA patients with amyloid, only half had renal failure or proteinuria during lifetime. In RA, most important determinants of mortality were CVDs, RA, and infections. In RA patients, RA deaths decreased over time, but this was not true for coronary deaths. Coronary death being less accurately diagnosed in RA may indicate that coronary heart disease (CHD) often goes unrecognized during lifetime. Thus, active search for CHD and its effective treatment is important to reduce cardiovascular mortality. Reactive amyloidosis may often go undetected. In RA patients with proteinuria or renal failure, as well as with active and long-lasting RA, a systematic search for amyloid is important to enable early diagnosis and early enhancement of therapy. This is essential to prevent clinical manifestations of amyloidosis such as renal failure, which has a poor prognosis.

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Polar Regions are an energy sink of the Earth system, as the Sun rays do not reach the Poles for half of the year, and hit them only at very low angles for the other half of the year. In summer, solar radiation is the dominant energy source for the Polar areas, therefore even small changes in the surface albedo strongly affect the surface energy balance and, thus, the speed and amount of snow and ice melting. In winter, the main heat sources for the atmosphere are the cyclones approaching from lower latitudes, and the atmosphere-surface heat transfer takes place through turbulent mixing and longwave radiation, the latter dominated by clouds. The aim of this thesis is to improve the knowledge about the surface and atmospheric processes that control the surface energy budget over snow and ice, with particular focus on albedo during the spring and summer seasons, on horizontal advection of heat, cloud longwave forcing, and turbulent mixing during the winter season. The critical importance of a correct albedo representation in models is illustrated through the analysis of the causes for the errors in the surface and near-surface air temperature produced in a short-range numerical weather forecast by the HIRLAM model. Then, the daily and seasonal variability of snow and ice albedo have been examined by analysing field measurements of albedo, carried out in different environments. On the basis of the data analysis, simple albedo parameterizations have been derived, which can be implemented into thermodynamic sea ice models, as well as numerical weather prediction and climate models. Field measurements of radiation and turbulent fluxes over the Bay of Bothnia (Baltic Sea) also allowed examining the impact of a large albedo change during the melting season on surface energy and ice mass budgets. When high contrasts in surface albedo are present, as in the case of snow covered areas next to open water, the effect of the surface albedo heterogeneity on the downwelling solar irradiance under overcast condition is very significant, although it is usually not accounted for in single column radiative transfer calculations. To account for this effect, an effective albedo parameterization based on three-dimensional Monte Carlo radiative transfer calculations has been developed. To test a potentially relevant application of the effective albedo parameterization, its performance in the ground-based retrieval of cloud optical depth was illustrated. Finally, the factors causing the large variations of the surface and near-surface temperatures over the Central Arctic during winter were examined. The relative importance of cloud radiative forcing, turbulent mixing, and lateral heat advection on the Arctic surface temperature were quantified through the analysis of direct observations from Russian drifting ice stations, with the lateral heat advection calculated from reanalysis products.

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The rise of Special education numbers in Finland has caused a situation where Finland s ten largest LEA s so called kymppikunnat (ten communes) have expressed their growing concern of organizing the special education in the current institutional settings. The LEA s started the conversation of redefining special education system in 2004. Their aim was to target the governments attention to the problematics of special education. By the request of the Ministry of Education the LEA s prepared a final report concerning the central questions in the Finnish special education system. On the basis of the LEA s survey it became even clearer that the legislation, funding system and curriculum are tightly linked together. The following LEA s took part into the writing process Espoo, Helsinki, Jyväskylä, Kuopio, Lahti, Lappeenranta, Tampere, Turku and Vantaa. The report was hand over to the Ministry of Education at 18.8.2006. After the delivery the Ministry organized special education development group meetings 17 times in the year 2007. The result of the LEA s report and the development meetings was a new Special Education Strategy 2007. I am observing the dialogue between administrational levels in governmental institutions change process. The research is a content analysis where I compare the Erityistä tukea tarvitsevan oppilaan opetuksen järjestämisen uudistaminen osana yhtenäistä perusopetusta- kohti laatua ja joustavuutta (The renewal of the organization of teaching for student with special educational needs as part of unified education for all - towards quality and flexibility) document to Erityisopetuksen strategia (Special education strategy) document. My aim was to find out how much of their own interests have the LEA s been able to integrate into the official governmental documentation. The data has been organized and analyzed quantitatively with Macros created as additional parts in Microsoft Excel software. The document material has also been arranged manually on sentence based categorization into an Excel matrix. The results have been theoretically viewed from the special education reform dialogue perspective, and from the angle of the change process of a bureaucratic institution. My target has been to provide a new viewpoint to the change of special education system as a bureaucratic institution. The education system has traditionally been understood as a machine bureaucracy. By the review provided in my pro gradu analysis it seems however that the administrational system in special education is more of a postmodern network bureaucracy than machine bureaucracy. The system appears to be constructed by overlapping, crossing and complex networks where things are been decided. These kinds of networks are called "governance networks . It seems that the governmental administrational - and politic levels, the third sector actors and other society s operators are mixed in decision making.

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Critical organization scholars have focused increasing attention on industrial and organizational restructurings such as shutdown decisions. However, we know little about the rhetorical strategies used to legitimate or resist plant closures in organizational negotiations. In this paper, we draw from New Rhetoric to analyze rhetorical struggles, strategies and dynamics in unfolding organizational negotiations. We focus on the shutdown of the bus body unit of the Swedish company Volvo in Finland. We distinguish five types of rhetorical legitimation strategies and dynamics. These include the three classical dynamics of logos (rational arguments), pathos (emotional moral arguments), and ethos (authority-based arguments), but also autopoiesis (autopoietic narratives), and cosmos (cosmological constructions). Our analysis adds to the previous studies explaining how organizational restructuring as a phenomenon is legitimated, how this legitimation has changed over time, and how contemporary industrial closures are legitimated in the media. This study also increases our theoretical understanding of the role of rhetoric in legitimation more generally.

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We have seen growing interest in discursive perspectives on strategy. This perspective holds great promise for development of an understanding on how strategy discourse and subjectivity are intertwined. We wish to add to this existing research by outlining a discursive struggle approach to subjectivity. To understand the complex subjectification and empowering/disempowering effects of organizational strategy discourse, this approach focuses on organization-specific discourse mobilizations an various ways of resistance. Drawing on an analysis of the discourses and practices of ‘strategic development’ in an engineering and consulting group we provide an empirical illustration of such struggles over subjectivity. In particular, we report three examples of competing ways of making sense of and giving sense to strategic development, with specific subjectification tendencies. First, we show how corporate management can mobilize and appropriate a specific kind of discourse to attempt to gain control of the organization, which tends to reproduce managerial hegemony, but also trigger discursive and other forms of resistance. Second, we will illustrate how middle managers resist this hegemony by initiating a strategy discourse of their own to create room for manoeuvre in controversial situations. Third, we show how project engineers can distance themselves from managerial-initiated strategy discourses to maintain a viable identity despite all kinds of pressures. Although our examples are case-specific, we believe that similar discursive dynamics also characterize strategizing in other organizations.

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Critical organization scholars have focused increasing attention on industrial and organizational restructurings such as shutdown decisions. However, little is known about the rhetorical strategies used to legitimate or resist plant closures in organizational negotiations. In this article, we draw from New Rhetoric to analyze rhetorical struggles, strategies and dynamics in unfolding organizational negotiations. We focus on the shutdown of the bus body unit of the Sweden-based Volvo Bus Corporation in Finland. We distinguish five types of rhetorical legitimation strategies and dynamics. These include the three classical dynamics of logos (rational arguments), pathos (emotional moral arguments), and ethos (authority-based arguments), but also autopoiesis (autopoietic narratives), and cosmos (cosmological constructions). Our analysis contributes to previous studies on organizational restructuring by providing a more nuanced understanding of how contemporary industrial closures are legitimated and resisted in organizational negotiations. This study also increases theoretical understanding of the role of rhetoric in legitimation more generally.

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The habit of "drinking smoke" , meaning tobacco smoking, caused a true controversy in early modern England. The new substance was used both for its alleged therapeutic properties as well as its narcotic effects. The dispute over tobacco continues the line of written controversies which were an important means of communication in the sixteenth and seventeenth century Europe. The tobacco controversy is special among medical controversies because the recreational use of tobacco soon spread and outweighed its medicinal use, ultimately causing a social and cultural crisis in England. This study examines how language is used in polemic discourse and argumentation. The material consists of medical texts arguing for and against tobacco in early modern England. The texts were compiled into an electronic corpus of tobacco texts (1577 1670) representing different genres and styles of writing. With the help of the corpus, the tobacco controversy is described and analyzed in the context of early modern medicine. A variety of methods suitable for the study of conflict discourse were used to assess internal and external text variation. The linguistic features examined include personal pronouns, intertextuality, structural components, and statistically derived keywords. A common thread in the work is persuasive language use manifested, for example, in the form of emotive adjectives and the generic use of pronouns; the latter is especially pronounced in the dichotomy between us and them. Controversies have not been studied in this manner before but the methods applied have supplemented each other and proven their suitability in the study of conflictive discourse. These methods can also be applied to present-day materials.