12 resultados para Range extension

em Helda - Digital Repository of University of Helsinki


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In this dissertation, I present an overall methodological framework for studying linguistic alternations, focusing specifically on lexical variation in denoting a single meaning, that is, synonymy. As the practical example, I employ the synonymous set of the four most common Finnish verbs denoting THINK, namely ajatella, miettiä, pohtia and harkita ‘think, reflect, ponder, consider’. As a continuation to previous work, I describe in considerable detail the extension of statistical methods from dichotomous linguistic settings (e.g., Gries 2003; Bresnan et al. 2007) to polytomous ones, that is, concerning more than two possible alternative outcomes. The applied statistical methods are arranged into a succession of stages with increasing complexity, proceeding from univariate via bivariate to multivariate techniques in the end. As the central multivariate method, I argue for the use of polytomous logistic regression and demonstrate its practical implementation to the studied phenomenon, thus extending the work by Bresnan et al. (2007), who applied simple (binary) logistic regression to a dichotomous structural alternation in English. The results of the various statistical analyses confirm that a wide range of contextual features across different categories are indeed associated with the use and selection of the selected think lexemes; however, a substantial part of these features are not exemplified in current Finnish lexicographical descriptions. The multivariate analysis results indicate that the semantic classifications of syntactic argument types are on the average the most distinctive feature category, followed by overall semantic characterizations of the verb chains, and then syntactic argument types alone, with morphological features pertaining to the verb chain and extra-linguistic features relegated to the last position. In terms of overall performance of the multivariate analysis and modeling, the prediction accuracy seems to reach a ceiling at a Recall rate of roughly two-thirds of the sentences in the research corpus. The analysis of these results suggests a limit to what can be explained and determined within the immediate sentential context and applying the conventional descriptive and analytical apparatus based on currently available linguistic theories and models. The results also support Bresnan’s (2007) and others’ (e.g., Bod et al. 2003) probabilistic view of the relationship between linguistic usage and the underlying linguistic system, in which only a minority of linguistic choices are categorical, given the known context – represented as a feature cluster – that can be analytically grasped and identified. Instead, most contexts exhibit degrees of variation as to their outcomes, resulting in proportionate choices over longer stretches of usage in texts or speech.

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Pharmacogenetics deals with genetically determined variation in drug response. In this context, three phase I drug-metabolizing enzymes, CYP2D6, CYP2C9, and CYP2C19, have a central role, affecting the metabolism of about 20-30% of clinically used drugs. Since genes coding for these enzymes in human populations exhibit high genetic polymorphism, they are of major pharmacogenetic importance. The aims of this study were to develop new genotyping methods for CYP2D6, CYP2C9, and CYP2C19 that would cover the most important genetic variants altering the enzyme activity, and, for the first time, to describe the distribution of genetic variation at these loci on global and microgeographic scales. In addition, pharmacogenetics was applied to a postmortem forensic setting to elucidate the role of genetic variation in drug intoxications, focusing mainly on cases related to tricyclic antidepressants, which are commonly involved in fatal drug poisonings in Finland. Genetic variability data were obtained by genotyping new population samples by the methods developed based on PCR and multiplex single-nucleotide primer extension reaction, as well as by collecting data from the literature. Data consisted of 138, 129, and 146 population samples for CYP2D6, CYP2C9, and CYP2C19, respectively. In addition, over 200 postmortem forensic cases were examined with respect to drug and metabolite concentrations and genotypic variation at CYP2D6 and CYP2C19. The distribution of genetic variation within and among human populations was analyzed by descriptive statistics and variance analysis and by correlating the genetic and geographic distances using Mantel tests and spatial autocorrelation. The correlation between phenotypic and genotypic variation in drug metabolism observed in postmortem cases was also analyzed statistically. The genotyping methods developed proved to be informative, technically feasible, and cost-effective. Detailed molecular analysis of CYP2D6 genetic variation in a global survey of human populations revealed that the pattern of variation was similar to those of neutral genomic markers. Most of the CYP2D6 diversity was observed within populations, and the spatial pattern of variation was best described as clinal. On the other hand, genetic variants of CYP2D6, CYP2C9, and CYP2C19 associated with altered enzymatic activity could reach extremely high frequencies in certain geographic regions. Pharmacogenetic variation may also be significantly affected by population-specific demographic histories, as seen within the Finnish population. When pharmacogenetics was applied to a postmortem forensic setting, a correlation between amitriptyline metabolic ratios and genetic variation at CYP2D6 and CYP2C19 was observed in the sample material, even in the presence of confounding factors typical for these cases. In addition, a case of doxepin-related fatal poisoning was shown to be associated with a genetic defect at CYP2D6. Each of the genes studied showed a distinct variation pattern in human populations and high frequencies of altered activity variants, which may reflect the neutral evolution and/or selective pressures caused by dietary or environmental exposure. The results are relevant also from the clinical point of view since the genetic variation at CYP2D6, CYP2C9, and CYP2C19 already has a range of clinical applications, e.g. in cancer treatment and oral anticoagulation therapy. This study revealed that pharmacogenetics may also contribute valuable information to the medicolegal investigation of sudden, unexpected deaths.

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Consumerism emphasises the patient s position and freedom of choice. Consumerism is being promoted by a range of phenomena occurring in society and health care. Different actors hold different views on the patient as a consumer and on his or her participation. Consumer demand is created outside the patient physician relationship and the commercialisation of services generates new expectations with respect to physician s work. More and more patients may be interested in adopting a more equal position in the care relationship, and trying to negotiate with the physician or to even dictate how he or she should be cared for. In Finland, very little research has been conducted on patients and consumers organising themselves at national system level, patients as choosers, and physicians attitudes to various consumerist phenomena or the choice made by the patient. In the empirical data for this study, the term consumer-patient refers to active consumers and patients making choices related to their clinical care prior to a physician s diagnosis. Consumer-patients are also represented by consumer and patient organisations and movements. The main research question is: How do physicians regard the care choice made by the patient? This question is addressed from a perspective encompassing patients and consumers organised activities and individuals active behaviour in health care as well as physicians experiences and their views on patients as consumers making choices related to their care. The first part (Study I), examines the patient organisation field, information sources used including the websites of such organisations, files from Finland s Slot Machine Association, RAY, a survey conducted by a Finnish television news department and interviews of patient organisations. Based on observation and a physician survey, Study II examines physicians attitudes to the idea that patients could obtain information through consumer movements about physicians care practices before seeking medical care. Studies III−IV use a physician survey to examine physicians attitudes to direct-to-consumer-advertising of prescription drugs (DTCA) and their experiences and views of patient requests related to treatments and examinations. Study V uses comparative surveys to examine the attitudes of health care professionals and the population to the introduction of new technologies in health care, using genetic screenings and tests as an example. The number of patient organisations increased, with a particular escalation as of the 1990s. The characteristics and operating methods of the organisations varied greatly. Physicians organisations adopted a negative or neutral attitude towards the consumer movements idea of distributing information on care practices, whereas individual physicians attitudes were slightly more positive. Physicians regarded direct-to-consumer-advertising of prescription drugs as negative, but took a more permissive attitude towards indirect advertising. More than every third physician considered drug advertisements in general to be harmful or useless in the distribution of drug information to patients or consumers. More than half of physicians conducting patient work reported that they (very) often encountered patients who stated upon arrival for a consultation that they wanted specific treatments or examinations, and that the number of such situations had increased. Such situations were viewed as positive with regard to the care relationship by every fifth physician and as negative by two fifths. Physicians justified a reserved attitude to the patients consumer role by referring to their medical expertise and position as care decision-makers, the patient physician relationship and the public health care system. Reasons for a positive attitude included the patient s participation and co-operation, the patient physician relationship and the patient s knowledge. Professionals were more reserved than lay people about the introduction and extension of genetic technologies in health care. A significant minority of the physicians did not take a clear pro or con attitude to the patients consumer role or to the use of new technologies in health care. The physicians age, gender, place of work and specialisation influenced their attitudes to the patient s consumer role, and private physicians viewed it in a more positive light than those working in public health care. Active consumer-patients challenge the society to hold a discussion of the patient s choice, participation in care decision-making and participation in health care policy in general. Their transformation into customers and consumers implies not only a new division of individuals roles and powers, but also contributes to changing relationships between system level roles: between citizens and the state and between public and private health care. This phenomenon raises various issues related to health care policy. In conclusion, topics are presented for discussion, practical measures and further research. Keywords: health care, consumerism, distribution of technologies, commercialisation, physicians, patients, consumers, patient s choice, patient s role.

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A wide range of models used in agriculture, ecology, carbon cycling, climate and other related studies require information on the amount of leaf material present in a given environment to correctly represent radiation, heat, momentum, water, and various gas exchanges with the overlying atmosphere or the underlying soil. Leaf area index (LAI) thus often features as a critical land surface variable in parameterisations of global and regional climate models, e.g., radiation uptake, precipitation interception, energy conversion, gas exchange and momentum, as all areas are substantially determined by the vegetation surface. Optical wavelengths of remote sensing are the common electromagnetic regions used for LAI estimations and generally for vegetation studies. The main purpose of this dissertation was to enhance the determination of LAI using close-range remote sensing (hemispherical photography), airborne remote sensing (high resolution colour and colour infrared imagery), and satellite remote sensing (high resolution SPOT 5 HRG imagery) optical observations. The commonly used light extinction models are applied at all levels of optical observations. For the sake of comparative analysis, LAI was further determined using statistical relationships between spectral vegetation index (SVI) and ground based LAI. The study areas of this dissertation focus on two regions, one located in Taita Hills, South-East Kenya characterised by tropical cloud forest and exotic plantations, and the other in Gatineau Park, Southern Quebec, Canada dominated by temperate hardwood forest. The sampling procedure of sky map of gap fraction and size from hemispherical photographs was proven to be one of the most crucial steps in the accurate determination of LAI. LAI and clumping index estimates were significantly affected by the variation of the size of sky segments for given zenith angle ranges. On sloping ground, gap fraction and size distributions present strong upslope/downslope asymmetry of foliage elements, and thus the correction and the sensitivity analysis for both LAI and clumping index computations were demonstrated. Several SVIs can be used for LAI mapping using empirical regression analysis provided that the sensitivities of SVIs at varying ranges of LAI are large enough. Large scale LAI inversion algorithms were demonstrated and were proven to be a considerably efficient alternative approach for LAI mapping. LAI can be estimated nonparametrically from the information contained solely in the remotely sensed dataset given that the upper-end (saturated SVI) value is accurately determined. However, further study is still required to devise a methodology as well as instrumentation to retrieve on-ground green leaf area index . Subsequently, the large scale LAI inversion algorithms presented in this work can be precisely validated. Finally, based on literature review and this dissertation, potential future research prospects and directions were recommended.

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Aerosol particles can cause detrimental environmental and health effects. The particles and their precursor gases are emitted from various anthropogenic and natural sources. It is important to know the origin and properties of aerosols to efficiently reduce their harmful effects. The diameter of aerosol particles (Dp) varies between ~0.001 and ~100 μm. Fine particles (PM2.5: Dp < 2.5 μm) are especially interesting because they are the most harmful and can be transported over long distances. The aim of this thesis is to study the impact on air quality by pollution episodes of long-range transported aerosols affecting the composition of the boundary-layer atmosphere in remote and relatively unpolluted regions of the world. The sources and physicochemical properties of aerosols were investigated in detail, based on various measurements (1) in southern Finland during selected long-range transport (LRT) pollution episodes and unpolluted periods and (2) over the Atlantic Ocean between Europe and Antarctica during a voyage. Furthermore, the frequency of LRT pollution episodes of fine particles in southern Finland was investigated over a period of 8 years, using long-term air quality monitoring data. In southern Finland, the annual mean PM2.5 mass concentrations were low but LRT caused high peaks of daily mean concentrations every year. At an urban background site in Helsinki, the updated WHO guideline value (24-h PM2.5 mean 25 μg/m3) was exceeded during 1-7 LRT episodes each year during 1999-2006. The daily mean concentrations varied between 25 and 49 μg/m3 during the episodes, which was 3-6 times higher than the mean concentration in the long term. The in-depth studies of selected LRT episodes in southern Finland revealed that biomass burning in agricultural fields and wildfires, occurring mainly in Eastern Europe, deteriorated air quality on a continental scale. The strongest LRT episodes of fine particles resulted from open biomass-burning fires but the emissions from other anthropogenic sources in Eastern Europe also caused significant LRT episodes. Particle mass and number concentrations increased strongly in the accumulation mode (Dp ~ 0.09-1 μm) during the LRT episodes. However, the concentrations of smaller particles (Dp < 0.09 μm) remained low or even decreased due to the uptake of vapours and molecular clusters by LRT particles. The chemical analysis of individual particles showed that the proportions of several anthropogenic particle types increased (e.g. tar balls, metal oxides/hydroxides, spherical silicate fly ash particles and various calcium-rich particles) in southern Finland during an LRT episode, when aerosols originated from the polluted regions of Eastern Europe and some open biomass-burning smoke was also brought in by LRT. During unpolluted periods when air masses arrived from the north, the proportions of marine aerosols increased. In unpolluted rural regions of southern Finland, both accumulation mode particles and small-sized (Dp ~ 1-3 μm) coarse mode particles originated mostly from LRT. However, the composition of particles was totally different in these size fractions. In both size fractions, strong internal mixing of chemical components was typical for LRT particles. Thus, the aging of particles has significant impacts on their chemical, hygroscopic and optical properties, which can largely alter the environmental and health effects of LRT aerosols. Over the Atlantic Ocean, the individual particle composition of small-sized (Dp ~ 1-3 μm) coarse mode particles was affected by continental aerosol plumes to distances of at least 100-1000 km from the coast (e.g. pollutants from industrialized Europe, desert dust from the Sahara and biomass-burning aerosols near the Gulf of Guinea). The rate of chloride depletion from sea-salt particles was high near the coasts of Europe and Africa when air masses arrived from polluted continental regions. Thus, the LRT of continental aerosols had significant impacts on the composition of the marine boundary-layer atmosphere and seawater. In conclusion, integration of the results obtained using different measurement techniques captured the large spatial and temporal variability of aerosols as observed at terrestrial and marine sites, and assisted in establishing the causal link between land-bound emissions, LRT and air quality.

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Spatial and temporal variation in the abundance of species can often be ascribed to spatial and temporal variation in the surrounding environment. Knowledge of how biotic and abiotic factors operate over different spatial and temporal scales in determining distribution, abundance, and structure of populations lies at the heart of ecology. The major part of the current ecological theory stems from studies carried out in central parts of the distributional range of species, whereas knowledge of how marginal populations function is inadequate. Understanding how marginal populations, living at the edge of their range, function is however in a key position to advance ecology and evolutionary biology as scientific disciplines. My thesis focuses on the factors affecting dynamics of marginal populations of blue mussels (Mytilus edulis) living close to their tolerance limits with regard to salinity. The thesis aims to highlight the dynamics at the edge of the range and contrast these with dynamics in more central parts of the range in order to understand the potential interplay between the central and the marginal part in the focal system. The objectives of the thesis are approached by studies on: (1) factors affecting regional patterns of the species, (2) long-term temporal dynamics of the focal species spaced along a regional salinity gradient, (3) selective predation by increasing populations of roach (Rutilus rutilus) when feeding on their main food item, the blue mussel, (4) the primary and secondary effects of local wave exposure gradients and (5) the role of small-scale habitat heterogeneity as determinants of large-scale pattern. The thesis shows that populations of blue mussels are largely determined by large scale changes in sea water salinity, affecting mainly recruitment success and longevity of local populations. In opposite to the traditional view, the thesis strongly indicate that vertebrate predators strongly affect abundance and size structure of blue mussel populations, and that the role of these predators increases towards the margin where populations are increasingly top-down controlled. The thesis also indicates that the positive role of biogenic habitat modifiers increases towards the marginal areas, where populations of blue mussels are largely recruitment limited. Finally, the thesis shows that local blue mussel populations are strongly dependent on high water turbulence, and therefore, dense populations are constrained to offshore habitats. Finally, the thesis suggests that ongoing sedimentation of rocky shores is detrimental for the species, affecting recruitment success and post-recruit survival, pushing stable mussel beds towards offshore areas. Ongoing large scale changes in the Baltic Sea, especially dilution processes with attendant effects, are predicted to substantially contract the distributional range of the mussel, but also affect more central populations. The thesis shows that in order to understand the functioning of marginal populations, research should (1) strive for multi-scale approaches in order to link ecosystem patterns with ecosystem processes, and (2) challenge the prevailing tenets that origin from research carried out in central areas that may not be valid at the edge.

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Climate change will influence the living conditions of all life on Earth. For some species the change in the environmental conditions that has occurred so far has already increased the risk of extinction, and the extinction risk is predicted to increase for large numbers of species in the future. Some species may have time to adapt to the changing environmental conditions, but the rate and magnitude of the change are too great to allow many species to survive via evolutionary changes. Species responses to climate change have been documented for some decades. Some groups of species, like many insects, respond readily to changes in temperature conditions and have shifted their distributions northwards to new climatically suitable regions. Such range shifts have been well documented especially in temperate zones. In this context, butterflies have been studied more than any other group of species, partly for the reason that their past geographical ranges are well documented, which facilitates species-climate modelling and other analyses. The aim of the modelling studies is to examine to what extent shifts in species distributions can be explained by climatic and other factors. Models can also be used to predict the future distributions of species. In this thesis, I have studied the response to climate change of one species of butterfly within one geographically restricted area. The study species, the European map butterfly (Araschnia levana), has expanded rapidly northwards in Finland during the last two decades. I used statistical and dynamic modelling approaches in combination with field studies to analyse the effects of climate warming and landscape structure on the expansion. I studied possible role of molecular variation in phosphoglucose isomerase (PGI), a glycolytic enzyme affecting flight metabolism and thereby flight performance, in the observed expansion of the map butterfly at two separate expansion fronts in Finland. The expansion rate of the map butterfly was shown to be correlated with the frequency of warmer than average summers during the study period. The result is in line with the greater probability of occurrence of the second generation during warm summers and previous results on this species showing greater mobility of the second than first generation individuals. The results of a field study in this thesis indicated low mobility of the first generation butterflies. Climatic variables alone were not sufficient to explain the observed expansion in Finland. There are also problems in transferring the climate model to new regions from the ones from which data were available to construct the model. The climate model predicted a wider distribution in the south-western part of Finland than what has been observed. Dynamic modelling of the expansion in response to landscape structure suggested that habitat and landscape structure influence the rate of expansion. In southern Finland the landscape structure may have slowed down the expansion rate. The results on PGI suggested that allelic variation in this enzyme may influence flight performance and thereby the rate of expansion. Genetic differences of the populations at the two expansion fronts may explain at least partly the observed differences in the rate of expansion. Individuals with the genotype associated with high flight metabolic rate were most frequent in eastern Finland, where the rate of range expansion has been highest.

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Background: Brachial plexus birth palsy (BPBP) most often occurs as a result of foetal-maternal disproportion. The C5 and C6 nerve roots of the brachial plexus are most frequently affected. In contrast, roots from the C7 to Th1 that result in total injury together with C5 and C6 injury, are affected in fewer than half of the patients. BPBP was first described by Smellie in 1764. Erb published his classical description of the injury in 1874 and his name became linked with the paralysis that is associated with upper root injury. Since then, early results of brachial plexus surgery have been reasonably well documented. However, from a clinical point of view not all primary results are maintained and there is also a need for later follow-up results. In addition most of the studies that are published emanate from highly specialized clinics and no nation wide epidemiological reports are available. One of the plexus injuries is the avulsion type, in which the nerve root or roots are ruptured at the neural cord. It has been speculated whether this might cause injury to the whole neural system or whether shoulder asymmetry and upper limb inequality results in postural deformities of the spine. Alternatively, avulsion could manifest as other signs and symptoms of the whole musculoskeletal system. In addition, there is no available information covering activities of daily living after obstetric brachial plexus surgery. Patients and methods: This was a population-based cross-sectional study on all patients who had undergone brachial plexus surgery with at least 5 years of follow-up. An incidence of 3.05/1000 for BPBP was obtained from the registers for this study period. A total of 1706 BPBP patients needing hospital treatment out of 1 717 057 newborns were registered in Finland between 1971 and 1997 inclusive. Of these BPBP patients, 124 (7.3%) underwent brachial plexus surgery at a mean age of 2.8 months (range: 0.4―13.2 months). Surgery was most often performed by direct neuroraphy after neuroma resection (53%). Depending on the phase of the study, 105 to 112 patients (85-90%) participated in a clinical and radiological follow-up assessment. The mean follow up time exceeded 13 years (range: 5.0―31.5 years). Functional status of the upper extremity was evaluated using Mallet, Gilbert and Raimondi scales. Isometric strength of the upper limb, sensation of the hand and stereognosis were evaluated for both the affected and unaffected sides then the differences and their ratios were calculated and recorded. In addition to the upper extremity, assessment of the spine and lower extremities were performed. Activities of daily living (ADL), participation in normal physical activities, and the use of physiotherapy and occupational therapy were recorded in a questionnaire. Results: The unaffected limb functioned as the dominant hand in all, except four patients. The mean length of the affected upper limb was 6 cm (range: 1-13.5 cm) shorter in 106 (95%) patients. Shoulder function was recorded as a mean Mallet score of 3 (range: 2―4) which was moderate. Both elbow function and hand function were good. The mean Gilbert elbow scale value was 3 (range: -1―5) and the mean Raimondi hand scale was 4 (range:1―5). One-third of the patients experienced pain in the affected limb including all those patients (n=9) who had clavicular non-union resulting from surgery. A total of 61 patients (57%) had an active shoulder external rotation of less than 0° and an active elbow extension deficiency was noted in 82 patients (77%) giving a mean of 26° (range: 5°―80°). In all, expect two patients, shoulder external rotation strength at a mean ratio 35% (range: 0―83%) and in all patients elbow flexion strength at a mean ratio of 41% (range: 0―79%) were impaired compared to the unaffected side. According to radiographs, incongruence of the glenohumeral joint was noted in 15 (16%) patients, whereas incongruence of the radiohumeral joint was found in 20 (21%) patients. Fine sensation was normal for 34/49 (69%) patients with C5-6 injury, for 15/31 (48%) with C5-7 and for only 8/25 (32%) of patients with total injury. Loss of protective sensation or absent sensation was noted in some palmar areas of the hand for 12/105 patients (11%). Normal stereognosis was recorded for 88/105 patients (84%). No significant inequalities in leg length were found and the incidence of structural scoliosis (1.7%) did not differ from that of the reference population. Nearly half of the patients (43%) had asynchronous motion of the upper limbs during gait, which was associated with impaired upper limb function. Data obtained from the completed questionnaires indicated that two thirds (63%) of the patients were satisfied with the functional outcome of the affected hand although one third of all patients needed help with ADL. Only a few patients were unable to participate in physical activities such as: bicycling, cross-country skiing or swimming. However, 71% of the patients reported problems related to the affected upper limb, such as muscle weakness and/or joint stiffness during the aforementioned activities. Incongruity of the radiohumeral joints, extent of the injury, avulsion type injury, age less than three months of age at the time of plexus surgery and inexperience of the surgeon was related to poor results as determined by multivariate analyses. Conclusions: Most of the patients had persistent sequelae, especially of shoulder function. Almost all measurements for the total injury group were poorer compared with those of the C5-6 type injury group. Most of the patients had asymmetry of the shoulder region and a shorter affected upper limb, which is a probable reason for having an abnormal gait. However, BPBP did not have an effect on normal growth of the lower extremities or the spine. Although, participation in physical activities was similar to that of the normal population, two-thirds of the patients reported problems. One-third of the patients needed help with ADL. During the period covered by this study, 7.3% BPBP of patients that needed hospital treatment had a brachial plexus operation, which amounts to fewer than 10 operations per year in Finland. It seems that better results of obstetric plexus surgery and more careful follow-up including opportunities for late reconstructive procedures will be expected, if the treatment is solely concentrated on by a few specialised teams.

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The purpose of this study was to produce information on and practical recommendations for informed decision-making on and capacity building for sustainable forest management (SFM) and good forest governance. This was done within the overall global framework for sustainable development with special emphasis on the EU and African frameworks and on Southern Sudan and Ethiopia in particular. The case studies on Southern Sudan and Ethiopia focused on local, national and regional issues. Moreover, this study attempted to provide both theoretical and practical new insight. The aim was to build an overall theoretical framework and to study its key contents and main implications for SFM and good forest governance at all administration levels, for providing new tools for capacity building in natural resources management. The theoretical framework and research approach were based on the original research problem and the general and specific aims of the study. The key elements of the framework encompass sustainable development, global and EU governance, sustainable forest management (SFM), good forest governance, as well as international and EU law. The selected research approach comprised matrix-based assessment of international, regional (EU and Africa) and national (Southern Sudan and Ethiopia) policy and legal documents. The specific case study on Southern Sudan also involved interviews and group discussions with local community members and government officials. As a whole, this study attempted to link the global, regional, national and local levels in forest-sector development and especially to analyse how the international policy development in environmental and forestry issues is reflected in field-level progress towards SFM and good forest governance, for the specific cases of Southern Sudan and Ethiopia. The results on Southern Sudan focused on the existing situation and perceived needs in capacity building for SFM and good forest governance at all administration levels. Specifically, the results of the case study on Southern Sudan presented the current situation in selected villages in the northern parts of Renk County in Upper Nile State, and the implications of Multilateral Environmental Agreements (MEAs) and of the new forest policy framework for capacity building actions. The results on Ethiopia focused on training, extension, research, education and new curriculum development within higher education institutions and particularly at the Wondo Genet College of Forestry and Natural Resources (WGCF-NR), which administratively lies under Hawassa University. The results suggest that, for both cases studies, informed decision-making on and capacity building for SFM and good forest governance require comprehensive, long-term, cross-sectoral, coherent and consistent approaches within the dynamic and evolving overall global framework, including its multiple inter-linked levels. The specific priority development and focus areas comprised the establishment of SFM and good forest governance in accordance with the overall sustainable development priorities and with more focus on the international trade in forest products that are derived from sustainable and legal sources with an emphasis on effective forest law enforcement and governance at all levels. In Upper Nile State in Southern Sudan there were positive development signals such as the will of the local people to plant more multipurpose trees on farmlands and range lands as well as the recognition of the importance of forests and trees for sustainable rural development where food security is a key element. In addition, it was evident that the local communities studied in Southern Sudan also wanted to establish good governance systems through partnerships with all actors and through increased local responsibilities. The results also suggest that the implementation of MEAs at the local level in Southern Sudan requires mutually supportive and coherent approaches within the agreements as well as significantly more resources and financial and technical assistance for capacity building, training and extension. Finally, the findings confirm the importance of full utilization of the existing local governance and management systems and their traditional and customary knowledge and practices, and of new development partnerships with full participation of all stakeholders. The planned new forest law for Southern Sudan, based on an already existing new forest policy, is expected to recognize the roles of local-level actors, and it would thus obviously facilitate the achieving of sustainable forest management.

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XVIII IUFRO World Congress, Ljubljana 1986.

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Various Tb theorems play a key role in the modern harmonic analysis. They provide characterizations for the boundedness of Calderón-Zygmund type singular integral operators. The general philosophy is that to conclude the boundedness of an operator T on some function space, one needs only to test it on some suitable function b. The main object of this dissertation is to prove very general Tb theorems. The dissertation consists of four research articles and an introductory part. The framework is general with respect to the domain (a metric space), the measure (an upper doubling measure) and the range (a UMD Banach space). Moreover, the used testing conditions are weak. In the first article a (global) Tb theorem on non-homogeneous metric spaces is proved. One of the main technical components is the construction of a randomization procedure for the metric dyadic cubes. The difficulty lies in the fact that metric spaces do not, in general, have a translation group. Also, the measures considered are more general than in the existing literature. This generality is genuinely important for some applications, including the result of Volberg and Wick concerning the characterization of measures for which the analytic Besov-Sobolev space embeds continuously into the space of square integrable functions. In the second article a vector-valued extension of the main result of the first article is considered. This theorem is a new contribution to the vector-valued literature, since previously such general domains and measures were not allowed. The third article deals with local Tb theorems both in the homogeneous and non-homogeneous situations. A modified version of the general non-homogeneous proof technique of Nazarov, Treil and Volberg is extended to cover the case of upper doubling measures. This technique is also used in the homogeneous setting to prove local Tb theorems with weak testing conditions introduced by Auscher, Hofmann, Muscalu, Tao and Thiele. This gives a completely new and direct proof of such results utilizing the full force of non-homogeneous analysis. The final article has to do with sharp weighted theory for maximal truncations of Calderón-Zygmund operators. This includes a reduction to certain Sawyer-type testing conditions, which are in the spirit of Tb theorems and thus of the dissertation. The article extends the sharp bounds previously known only for untruncated operators, and also proves sharp weak type results, which are new even for untruncated operators. New techniques are introduced to overcome the difficulties introduced by the non-linearity of maximal truncations.