191 resultados para Keywords: Ants


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Cathepsin D (CTSD) is a lysosomal protease, the deficiency of which is fatal and associated with neurodegeneration. CTSD knock-out mice, which die at the age of four weeks, show intestinal necrosis, loss of lymphoid cells and moderate pathological changes in the brain. An active-site mutation in the CTSD gene underlies a neurodegenerative disease in newborn sheep, characterized by brain atrophy without any changes to visceral tissues. The CTSD deficiences belong to the group of neuronal ceroid-lipofuscinoses (NCLs), severe neurodegenerative lysosomal storage disorders. The aim of this thesis was to examine the molecular and cellular mechanisms behind neurodegeneration in CTSD deficiency. We found the developmental expression pattern of CTSD to resemble that of synaptophysin and the increasing expression of CTSD to coincide with the active period of myelination in the rat brain, suggesting a role for CTSD in early rat brain development. An active-site mutation underlying the congenital ovine NCL not only affected enzymatic activity, but also changed the stability, processing and transport of the mutant protein, possibly contributing to the disease pathogenesis. We also provide CTSD deficiency as a first molecular explanation for human congenital NCL, a lysosomal storage disorder, characterized by neuronal loss and demyelination in the central nervous system. Finally, we show the first evidence for synaptic abnormalities and thalamocortical changes in CTSD-deficient mice at the molecular and ultrastructural levels. Keywords: cathepsin D, congenital, cortex, lysosomal storage disorder, lysosome, mutation, neurodegeneration, neuronal ceroid-lipofuscinosis, overexpression, synapse, thalamus

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The aim of this study was to measure seasonal variation in mood and behaviour. The dual vulnerability and latitude effect hypothesis, the risk of increased appetite, weight and other seasonal symptoms to develop metabolic syndrome, and perception of low illumination in quality of life and mental well-being were assessed. These variations are prevalent in persons who live in high latitudes and need balancing of metabolic processes to adapt to environmental changes due to seasons. A randomized sample of 8028 adults aged 30 and over (55% women) participated in an epidemiological health examination study, The Health 2000, applying the probability proportional to population size method for a range of socio-demographic characteristics. They were present in a face-to-face interview at home and health status examination. The questionnaires included the modified versions of the Seasonal Pattern Assessment Questionnaire (SPAQ) and Beck Depression Inventory (BDI), the Health Related Quality of Life (HRQoL) instrument 15D, and the General Health Questionnaire (GHQ). The structured and computerized Munich Composite International Diagnostic Interview (M-CIDI) as part of the interview was used to assess diagnoses of mental disorders, and, the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATPIII) criteria were assessed using all the available information to detect metabolic syndrome. A key finding was that 85% of this nationwide representative sample had seasonal variation in mood and behaviour. Approximately 9% of the study population presented combined seasonal and depressive symptoms with a significant association between their scores, and 2.6% had symptoms that corresponded to Seasonal Affective Disorder (SAD) in severity. Seasonal variations in weight and appetite are two important components that increase the risk of metabolic syndrome. Other factors such as waist circumference and major depressive disorder contributed to the metabolic syndrome as well. Persons reported of having seasonal symptoms were associated with a poorer quality of life and compromised mental well-being, especially if indoors illumination at home and/or at work was experienced as being low. Seasonal and circadian misalignments are suggested to associate with metabolic disorders, and could be remarked if individuals perceive low illumination levels at home and/or at work that affect the health-related quality of life and mental well-being. Keywords: depression, health-related quality of life, illumination, latitude, mental well-being, metabolic syndrome, seasonal variation, winter.

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In humans with a loss of uricase the final oxidation product of purine catabolism is uric acid (UA). The prevalence of hyperuricemia has been increasing around the world accompanied by a rapid increase in obesity and diabetes. Since hyperuricemia was first described as being associated with hyperglycemia and hypertension by Kylin in 1923, there has been a growing interest in the association between elevated UA and other metabolic abnormalities of hyperglycemia, abdominal obesity, dyslipidemia, and hypertension. The direction of causality between hyperuricemia and metabolic disorders, however, is unceartain. The association of UA with metabolic abnormalities still needs to be delineated in population samples. Our overall aims were to study the prevalence of hyperuricemia and the metabolic factors clustering with hyperuricemia, to explore the dynamical changes in blood UA levels with the deterioration in glucose metabolism and to estimate the predictive capability of UA in the development of diabetes. Four population-based surveys for diabetes and other non-communicable diseases were conducted in 1987, 1992, and 1998 in Mauritius, and in 2001-2002 in Qingdao, China. The Qingdao study comprised 1 288 Chinese men and 2 344 women between 20-74, and the Mauritius study consisted of 3 784 Mauritian Indian and Mauritian Creole men and 4 442 women between 25-74. In Mauritius, re-exams were made in 1992 and/or 1998 for 1 941 men (1 409 Indians and 532 Creoles) and 2 318 non pregnant women (1 645 Indians and 673 Creoles), free of diabetes, cardiovascular diseases, and gout at baseline examinations in 1987 or 1992, using the same study protocol. The questionnaire was designed to collect demographic details, physical examinations and standard 75g oral glucose tolerance tests were performed in all cohorts. Fasting blood UA and lipid profiles were also determined. The age-standardized prevalence in Chinese living in Qingdao was 25.3% for hyperuricemia (defined as fasting serum UA > 420 μmol/l in men and > 360 μmol/l in women) and 0.36% for gout in adults between 20-74. Hyperuricemia was more prevalent in men than in women. One standard deviation increase in UA concentration was associated with the clustering of metabolic risk factors for both men and women in three ethnic groups. Waist circumference, body mass index, and serum triglycerides appeared to be independently associated with hyperuricemia in both sexes and in all ethnic groups except in Chinese women, in whom triglycerides, high-density lipoprotein cholesterol, and total cholesterol were associated with hyperuricemia. Serum UA increased with increasing fasting plasma glucose levels up to a value of 7.0 mmol/l, but significantly decreased thereafter in mainland Chinese. An inverse relationship occurred between 2-h plasma glucose and serum UA when 2-h plasma glucose higher than 8.0 mmol/l. In the prospective study in Mauritius, 337 (17.4%) men and 379 (16.4%) women developed diabetes during the follow-up. Elevated UA levels at baseline increased 1.14-fold in risk of incident diabetes in Indian men and 1.37-fold in Creole men, but no significant risk was observed in women. In conclusion, the prevalence of hyperuricemia was high in Chinese in Qingdao, blood UA was associated with the clustering of metabolic risk factors in Mauritian Indian, Mauritian Creole, and Chinese living in Qingdao, and a high baseline UA level independently predicted the development of diabetes in Mauritian men. The clinical use of UA as a marker of hyperglycemia and other metabolic disorders needs to be further studied. Keywords: Uric acid, Hyperuricemia, Risk factors, Type 2 Diabetes, Incidence, Mauritius, Chinese

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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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The first aim of this thesis was to explore the structural characteristics of near-natural forests and to quantify how human utilization has changed them. For this, we examined the stand characteristics in Norway spruce Picea abies (L.) Karst-dominated old-growth stands in northwestern Russia and in old Scots pine Pinus sylvestris L.-dominated stands in three regions from southern Finland to northwestern Russia. In the second study, we also compared stands with different degrees of human impact, from near-natural stands and stands selectively cut in the past to managed stands. Secondly, we used an experimental approach to study the short-term effects of different restorative treatments on forest structure and regeneration in managed Picea abies stands in southern Finland. Restorative treatments consisted of a partial cut combined with three levels of coarse woody debris retention, and a fire/no-fire treatment. In addition, we examined burned and unburned reference stands without cutting treatments. Results from near-natural Picea abies forests emphasize the dynamic character of old-growth forests, the variety of late-successional forest structures, and the fact that extended time periods are needed to attain certain late-successional stages with specific structural and habitat attributes, such as large-diameter deciduous trees and a variety of deadwood. The results from old Pinus sylvestris-dominated forests showed that human impact in the form of forest utilization and fire exclusion has strongly modified and reduced the structural complexity of stands. Consequently, small protected forest fragments in Finland may not serve as valid natural reference areas for forest restoration. However, results from the restoration experiment showed that early-successional natural stand characteristics can be restored to structurally impoverished managed Picea abies stands, despite a significant portion of wood volume being harvested. A variety of restoration methods is needed, due to differences in the condition of the forest when restoration is initiated and the variety of successional stages of forest structures after anthropogenic and natural disturbances. Keywords: dead wood, disturbance dynamic, fire, near-natural stand, rehabilitation, succession

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This study addresses three important issues in tree bucking optimization in the context of cut-to-length harvesting. (1) Would the fit between the log demand and log output distributions be better if the price and/or demand matrices controlling the bucking decisions on modern cut-to-length harvesters were adjusted to the unique conditions of each individual stand? (2) In what ways can we generate stand and product specific price and demand matrices? (3) What alternatives do we have to measure the fit between the log demand and log output distributions, and what would be an ideal goodness-of-fit measure? Three iterative search systems were developed for seeking stand-specific price and demand matrix sets: (1) A fuzzy logic control system for calibrating the price matrix of one log product for one stand at a time (the stand-level one-product approach); (2) a genetic algorithm system for adjusting the price matrices of one log product in parallel for several stands (the forest-level one-product approach); and (3) a genetic algorithm system for dividing the overall demand matrix of each of the several log products into stand-specific sub-demands simultaneously for several stands and products (the forest-level multi-product approach). The stem material used for testing the performance of the stand-specific price and demand matrices against that of the reference matrices was comprised of 9 155 Norway spruce (Picea abies (L.) Karst.) sawlog stems gathered by harvesters from 15 mature spruce-dominated stands in southern Finland. The reference price and demand matrices were either direct copies or slightly modified versions of those used by two Finnish sawmilling companies. Two types of stand-specific bucking matrices were compiled for each log product. One was from the harvester-collected stem profiles and the other was from the pre-harvest inventory data. Four goodness-of-fit measures were analyzed for their appropriateness in determining the similarity between the log demand and log output distributions: (1) the apportionment degree (index), (2) the chi-square statistic, (3) Laspeyres quantity index, and (4) the price-weighted apportionment degree. The study confirmed that any improvement in the fit between the log demand and log output distributions can only be realized at the expense of log volumes produced. Stand-level pre-control of price matrices was found to be advantageous, provided the control is done with perfect stem data. Forest-level pre-control of price matrices resulted in no improvement in the cumulative apportionment degree. Cutting stands under the control of stand-specific demand matrices yielded a better total fit between the demand and output matrices at the forest level than was obtained by cutting each stand with non-stand-specific reference matrices. The theoretical and experimental analyses suggest that none of the three alternative goodness-of-fit measures clearly outperforms the traditional apportionment degree measure. Keywords: harvesting, tree bucking optimization, simulation, fuzzy control, genetic algorithms, goodness-of-fit

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The use of remote sensing imagery as auxiliary data in forest inventory is based on the correlation between features extracted from the images and the ground truth. The bidirectional reflectance and radial displacement cause variation in image features located in different segments of the image but forest characteristics remaining the same. The variation has so far been diminished by different radiometric corrections. In this study the use of sun azimuth based converted image co-ordinates was examined to supplement auxiliary data extracted from digitised aerial photographs. The method was considered as an alternative for radiometric corrections. Additionally, the usefulness of multi-image interpretation of digitised aerial photographs in regression estimation of forest characteristics was studied. The state owned study area located in Leivonmäki, Central Finland and the study material consisted of five digitised and ortho-rectified colour-infrared (CIR) aerial photographs and field measurements of 388 plots, out of which 194 were relascope (Bitterlich) plots and 194 were concentric circular plots. Both the image data and the field measurements were from the year 1999. When examining the effect of the location of the image point on pixel values and texture features of Finnish forest plots in digitised CIR photographs the clearest differences were found between front-and back-lighted image halves. Inside the image half the differences between different blocks were clearly bigger on the front-lighted half than on the back-lighted half. The strength of the phenomenon varied by forest category. The differences between pixel values extracted from different image blocks were greatest in developed and mature stands and smallest in young stands. The differences between texture features were greatest in developing stands and smallest in young and mature stands. The logarithm of timber volume per hectare and the angular transformation of the proportion of broadleaved trees of the total volume were used as dependent variables in regression models. Five different converted image co-ordinates based trend surfaces were used in models in order to diminish the effect of the bidirectional reflectance. The reference model of total volume, in which the location of the image point had been ignored, resulted in RMSE of 1,268 calculated from test material. The best of the trend surfaces was the complete third order surface, which resulted in RMSE of 1,107. The reference model of the proportion of broadleaved trees resulted in RMSE of 0,4292 and the second order trend surface was the best, resulting in RMSE of 0,4270. The trend surface method is applicable, but it has to be applied by forest category and by variable. The usefulness of multi-image interpretation of digitised aerial photographs was studied by building comparable regression models using either the front-lighted image features, back-lighted image features or both. The two-image model turned out to be slightly better than the one-image models in total volume estimation. The best one-image model resulted in RMSE of 1,098 and the two-image model resulted in RMSE of 1,090. The homologous features did not improve the models of the proportion of broadleaved trees. The overall result gives motivation for further research of multi-image interpretation. The focus may be improving regression estimation and feature selection or examination of stratification used in two-phase sampling inventory techniques. Keywords: forest inventory, digitised aerial photograph, bidirectional reflectance, converted image co­ordinates, regression estimation, multi-image interpretation, pixel value, texture, trend surface

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The studies presented in this thesis contribute to the understanding of evolutionary ecology of three major viruses threatening cultivated sweetpotato (Ipomoea batatas Lam) in East Africa: Sweet potato feathery mottle virus (SPFMV; genus Potyvirus; Potyviridae), Sweet potato chlorotic stunt virus (SPCSV; genus Crinivirus; Closteroviridae) and Sweet potato mild mottle virus (SPMMV; genus Ipomovirus; Potyviridae). The viruses were serologically detected and the positive results confirmed by RT-PCR and sequencing. SPFMV was detected in 24 wild plant species of family Convolvulacea (genera Ipomoea, Lepistemon and Hewittia), of which 19 species were new natural hosts for SPFMV. SPMMV and SPCSV were detected in wild plants belonging to 21 and 12 species (genera Ipomoea, Lepistemon and Hewittia), respectively, all of which were previously unknown to be natural hosts of these viruses. SPFMV was the most abundant virus being detected in 17% of the plants, while SPMMV and SPCSV were detected in 9.8% and 5.4% of the assessed plants, respectively. Wild plants in Uganda were infected with the East African (EA), common (C), and the ordinary (O) strains, or co-infected with the EA and the C strain of SPFMV. The viruses and virus-like diseases were more frequent in the eastern agro-ecological zone than the western and central zones, which contrasted with known incidences of these viruses in sweetpotato crops, except for northern zone where incidences were lowest in wild plants as in sweetpotato. The NIb/CP junction in SPMMV was determined experimentally which facilitated CP-based phylogenetic and evolutionary analyses of SPMMV. Isolates of all the three viruses from wild plants were genetically similar to those found in cultivated sweetpotatoes in East Africa. There was no evidence of host-driven population genetic structures suggesting frequent transmission of these viruses between their wild and cultivated hosts. The p22 RNA silencing suppressor-encoding sequence was absent in a few SPCSV isolates, but regardless of this, SPCSV isolates incited sweet potato virus disease (SPVD) in sweetpotato plants co-infected with SPFMV, indicating that p22 is redundant for synergism between SCSV and SPFMV. Molecular evolutionary analysis revealed that isolates of strain EA of SPFMV that is largely restricted geographically in East Africa experience frequent recombination in comparison to isolates of strain C that is globally distributed. Moreover, non-homologous recombination events between strains EA and C were rare, despite frequent co-infections of these strains in wild plants, suggesting purifying selection against non-homologous recombinants between these strains or that such recombinants are mostly not infectious. Recombination was detected also in the 5 - and 3 -proximal regions of the SPMMV genome providing the first evidence of recombination in genus Ipomovirus, but no recombination events were detected in the characterized genomic regions of SPCSV. Strong purifying selection was implicated on evolution of majority of amino acids of the proteins encoded by the analyzed genomic regions of SPFMV, SPMMV and SPCSV. However, positive selection was predicted on 17 amino acids distributed over the whole the coat protein (CP) in the globally distributed strain C, as compared to only 4 amino acids in the multifunctional CP N-terminus (CP-NT) of strain EA largely restricted geographically to East Africa. A few amino acid sites in the N-terminus of SPMMV P1, the p7 protein and RNA silencing suppressor proteins p22 and RNase3 of SPCSV were also submitted to positive selection. Positively selected amino acids may constitute ligand-binding domains that determine interactions with plant host and/or insect vector factors. The P1 proteinase of SPMMV (genus Ipomovirus) seems to respond to needs of adaptation, which was not observed with the helper component proteinase (HC-Pro) of SPMMV, although the HC-Pro is responsible for many important molecular interactions in genus Potyvirus. Because the centre of origin of cultivated sweetpotato is in the Americas from where the crop was dispersed to other continents in recent history (except for the Australasia and South Pacific region), it would be expected that identical viruses and their strains occur worldwide, presuming virus dispersal with the host. Apparently, this seems not to be the case with SPMMV, the strain EA of SPFMV and the strain EA of SPCSV that are largely geographically confined in East Africa where they are predominant and occur both in natural and agro-ecosystems. The geographical distribution of plant viruses is constrained more by virus-vector relations than by virus-host interactions, which in accordance of the wide range of natural host species and the geographical confinement to East Africa suggest that these viruses existed in East African wild plants before the introduction of sweetpotato. Subsequently, these studies provide compelling evidence that East Africa constitutes a cradle of SPFMV strain EA, SPCSV strain EA, and SPMMV. Therefore, sweet potato virus disease (SPVD) in East Africa may be one of the examples of damaging virus diseases resulting from exchange of viruses between introduced crops and indigenous wild plant species. Keywords: Convolvulaceae, East Africa, epidemiology, evolution, genetic variability, Ipomoea, recombination, SPCSV, SPFMV, SPMMV, selection pressure, sweetpotato, wild plant species Author s Address: Arthur K. Tugume, Department of Agricultural Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Latokartanonkaari 7, P.O Box 27, FIN-00014, Helsinki, Finland. Email: tugume.arthur@helsinki.fi Author s Present Address: Arthur K. Tugume, Department of Botany, Faculty of Science, Makerere University, P.O. Box 7062, Kampala, Uganda. Email: aktugume@botany.mak.ac.ug, tugumeka@yahoo.com

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Biological control techniques attract increasing attention as one of the sustainable alternatives to pesticide use in integrated pest management programs. In order to develop sustainable pest management methods for arable crops based on entomopathogenic nematodes (EPN), their efficacy and persistence needed to be investigated, and an economically feasible delivery system had to be developed. In this study, first a survey of entomopathogens was conducted, and a system approach was tested, using the oilseed Brassica (OSB) growing system (OSB, spring wheat, and red clover) as a model. The system approach aimed at determining the potential of Steinernema feltiae (Filipjev) for the control of OSB pests, developing OSB rotation schemes that support EPN persistence, and investigating the impact of the selected biotic and abiotic factors on efficacy and persistence of EPN. This study employed abductive logic (which employs constant interplay between the theory and empirical observation), quantitative methods, and a case study on OSB. Laboratory and field experiments were carried out, and two types of pathogen surveys. A horizontal survey included OSB fields across Estonia, Germany, Poland, Sweden and the UK, while a vertical survey included sampling from two sets of differently managed experimental fields during three years. A new approach was introduced for measuring occurrence, where the prevalence and relative intensity of entomopathogens, biotic agents, and unidentified insect antagonists were determined. The effect of dose, timing, and the application method on S. feltiae in the control of pests in OSB, and the potential of a controlled release delivery system (CRS) were evaluated in the field. Studies on the impact of selected biotic and abiotc factors (Brassica plant, bait insects, developmental stages of Meligethes aeneus Fab., Isaria fumosorosea Wize (Ifr), and organic and synthetic fertilizers) on the efficacy of S. feltiae were conducted in the laboratory. Persistence of S. feltiae in the OSB growing system, and the effect of dose, timing, and the application method, was assessed in the field as part of the efficacy experiments. The impact of selected biotic and abiotic factors on S. feltiae persistence was assessed in laboratory experiments. The pathogen survey showed that the occurrence of entomopathogens is low in the OSB growing system, and that a management system causing less disturbance (ICM) to the soil increases the relative intensity of insect parasitic nematodes and other insect antagonists. A longer study period is required to show any possible impact of ICM on the relative intensity of entomopathogenic fungi, or on the prevalence of entomopathogens. Two different measures of the occurrence yielded different results: the relative intensity revealed the difference between the two different crop management methods, while prevalence did not. The highest efficacy of S. feltiae was achieved by using a low dose and targeting all stages of M. aeneus. When only the larval stage was targeted, the application method and dose had no significant effect. The CRS decreased the pest abundance significantly more than the surface application method. S. feltiae persisted in the OSB fields in Finland for several months, but did not survive the winter. The strain survived for 7 months when it was applied in autumn in Germany, but its populations declined rapidly after winter. The examined biotic and abiotic factors had variable impacts on S. feltiae efficacy and persistence. The two measures, prevalence and relative intensity of entomopathogens, gave valuable information for their use in biocontrol programs. The recommended biocontrol strategy for OSB growing in Finland is inundation and seasonal inoculation of EPN. The impact of some biotic and abiotic factors on S. feltiae efficacy and persistence is significant, and can be used to improve the efficacy of EPN. The CRS is a novel alternative for EPN application, and should also be considered for use on other crops. Keywords: Biological control, inundation, inoculation, conservation, formulation, slow release method, crop rotation, Entomopathogenic nematodes, Steinernema feltiae, oilseed rape pests, Meligethes aeneus, Phyllotreta spp., occurrence, prevalence, intensity, efficacy, persistence, field, Isaria fumosorosea, biotic factors, abiotic factors, interaction, impact, insect stages, integrated crop management, standard (conventional) crop management

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Rhizoremediation is the use of microbial populations present in the rhizosphere of plants for environmental cleanup. The idea of this work was that bacteria living in the rhizosphere of a nitrogen-fixing leguminous plant, goat's rue (Galega orientalis), could take part in the degradation of harmful monoaromatic hydrocarbons, such as benzene, toluene and xylene (BTEX), from oil-contaminated soils. In addition to chemical (e.g. pollutant concentration) and physical (e.g. soil structure) information, the knowledge of biological aspects (e.g. bacteria and their catabolic genes) is essential when developing the rhizoremediation into controlled and effective bioremediation practice. Therefore, the need for reliable biomonitoring methods is obvious. The main aims of this thesis were to evaluate the symbiotic G. orientalis - Rhizobium galegae system for rhizoremediation of oil-contaminated soils, to develop molecular methods for biomonitoring, and to apply these methods for studying the microbiology of rhizoremediation. In vitro, Galega plants and rhizobia remained viable in m-toluate concentrations up to 3000 mg/l. Plant growth and nodulation were inhibited in 500 mg/l m-toluate, but were restored when plants were transferred to clean medium. In the greenhouse, Galega showed good growth, nodulation and nitrogen fixation, and developed a strong rhizosphere in soils contaminated with oil or spiked with 2000 mg/l m-toluate. The high aromatic tolerance of R. galegae and the viability of Galega plants in oil-polluted soils proved this legume system to be a promising method for the rhizoremediation of oil-contaminated soils. Molecular biomonitoring methods were designed and/or developed further for bacteria and their degradation genes. A combination of genomic fingerprinting ((GTG)5-PCR), taxonomic ribotyping of 16S rRNA genes and partial 16S rRNA gene sequencing were chosen for molecular grouping of culturable, heterogeneous rhizosphere bacteria. PCR primers specific for the xylE gene were designed for TOL plasmid detection. Amplified enzyme-coding DNA restriction analysis (AEDRA) with AluI was used to profile both TOL plasmids (xylE primers) and, in general, aromatics-degrading plasmids (C230 primers). The sensitivity of the direct monitoring of TOL plasmids in soil was enhanced by nested C23O-xylE-PCR. Rhizosphere bacteria were isolated from the greenhouse and field lysimeter experiments. High genetic diversity was observed among the 50 isolated, m-toluate tolerating rhizosphere bacteria in the form of five major lineages of the Bacteria domain. Gram-positive Rhodococcus, Bacillus and Arthrobacter and gram-negative Pseudomonas were the most abundant genera. The inoculum Pseudomonas putida PaW85/pWW0 was not found in the rhizosphere samples. Even if there were no ecological niches available for the bioaugmentation bacterium itself, its conjugative catabolic plasmid might have had some additional value for other bacterial species and thus, for rhizoremediation. Only 10 to 20% of the isolated, m-toluate tolerating bacterial strains were also able to degrade m-toluate. TOL plasmids were a major group of catabolic plasmids among these bacteria. The ability to degrade m-toluate by using enzymes encoded by a TOL plasmid was detected only in species of the genus Pseudomonas, and the best m-toluate degraders were these Pseudomonas species. Strain-specific differences in degradation abilities were found for P.oryzihabitans and P. migulae: some of these strains harbored a TOL plasmid - a new finding observed in this work, indicating putative horizontal plasmid transfer in the rhizosphere. One P. oryzihabitans strain harbored the pWW0 plasmid that had probably conjugated from the bioaugmentation Pseudomonas. Some P. migulae and P. oryzihabitans strains seemed to harbor both the pWW0- and the pDK1-type TOL plasmid. Alternatively, they might have harbored a TOL plasmid with both the pWW0- and the pDK1-type xylE gene. The breakdown of m-toluate by gram-negative bacteria was not restricted to the TOL pathway. Also some gram-positive Rhodococcus erythropolis and Arthrobacter aurescens strains were able to degrade m-toluate in the absence of a TOL plasmid. Three aspects of the rhizosphere effect of G. orientalis were manifested in oil-contaminated soil in the field: 1) G. orientalis and Pseudomonas bioaugmentation increased the amount of rhizosphere bacteria. G. orientalis especially together with Pseudomonas bioaugmentation increased the numbers of m-toluate utilizing and catechol positive bacteria indicating an increase in degradation potential. 2) Also the bacterial diversity, when measured as the amount of ribotypes, was increased in the Galega rhizosphere with or without Pseudomonas bioaugmentation. However, the diversity of m-toluate utilizing bacteria did not significantly increase. At the community level, by using the 16S rRNA gene PCR-DGGE method, the highest diversity of species was also observed in vegetated soils compared with non-vegetated soils. Diversified communities may best guarantee the overall success in rhizoremediation by offering various genetic machineries for catabolic processes. 3) At the end of the experiment, no TOL plasmid could be detected by direct DNA analysis in soil treated with both G. orientalis and Pseudomonas. The detection limit for TOL plasmids was encountered indicating decreased amount of degradation plasmids and thus, the success of rhizoremediation. The use of G. orientalis for rhizoremediation is unique. In this thesis new information was obtained about the rhizosphere effect of Galega orientalis in BTEX contaminated soils. The molecular biomonitoring methods can be applied for several purposes within environmental biotechnology, such as for evaluating the intrinsic biodegradation potential, monitoring the enhanced bioremediation, and estimating the success of bioremediation. Environmental protection by using nature's own resources and thus, acting according to the principle of sustainable development, would be both economically and environmentally beneficial for society. Keywords: molecular biomonitoring, genetic fingerprinting, soil bacteria, bacterial diversity, TOL plasmid, catabolic genes, horizontal gene transfer, rhizoremediation, rhizosphere effect, Galega orientalis, aerobic biodegradation, petroleum hydrocarbons, BTEX

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The current study of Scandinavian multinational corporate subsidiaries in the rapidly growing Eastern European market, due to their particular organizational structure, attempts to gain some new insights into processes and potential benefits of knowledge and technology transfer. This study explores how to succeed in knowledge transfer and to become more competitive, driven by the need to improve transfer of systematic knowledge for the manufacture of product and service provisions in newly entered market. The scope of current research is exactly limited to multinational corporations, which are defined as enterprises comprising entities in two or more countries, regardless of legal forms and field of activity of those entities, and which operate under a system of decision-making permitting coherent policies and a common strategy through one or more decision-making centers. The entities are linked, by ownership, and able to exercise influence over the activities of the others; and, in particular, to share the knowledge, resources, and responsibilities with others. The research question is "How and to which extent can knowledge-transfer influence a company's technological competence and economic competitiveness?" and try to find out what particular forces and factors affect the development of subsidiary competencies; what factors influence the corporate integration and use of the subsidiary's competencies; and what may increase competitiveness of MNC pursuing leading position in entered market. The empirical part of the research was based on qualitative analyses of twenty interviews conducted among employees in Scandinavian MNC subsidiary units situated in Ukraine, using structured sequence of questions with open-ended answers. The data was investigated by comparison case analyses to literature framework. Findings indicate that a technological competence developed in one subsidiary will lead to an integration of that competence with other corporate units within the MNC. Success increasingly depends upon people's learning. The local economic area is crucial for understanding competition and industrial performance, as there seems to be a clear link between the performance of subsidiaries and the conditions prevailing in their environment. The linkage between competitive advantage and company's success is mutually dependent. Observation suggests that companies can be characterized as clusters of complementary activities such as R&D, administration, marketing, manufacturing and distribution. Study identifies barriers and obstacles in technology and knowledge transfer that is relevant for the subsidiaries' competence development. The accumulated experience can be implemented in new entered market with simple procedures, and at a low cost under specific circumstances, by cloning. The main goal is focused to support company prosperity, making more profits and sustaining an increased market share by improved product quality and/or reduced production cost of the subsidiaries through cloning approach. Keywords: multinational corporation; technology transfer; knowledge transfer; subsidiary competence; barriers and obstacles; competitive advantage; Eastern European market

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A View into the World of Kitchen: Development and retention of a leading position in the market of kitchen interiors - a case study of 20 years. This study focuses on the development of a kitchen interiors company, presently called Novart Inc., into the leading company of the industry from 1980´s to the present. The objective of the study is to describe the effects of strategic choices, the decisions of the management and the owner´s direction and control to the build up and the retaining of the leading position in the market. From theory point of view, strategic choices refer to com-pany purchases as corporate-level strategies, and business and marketing strategies. The empirical research was carried out in two phases and it is based on various company documents and records, and on the intensive interviews of seven key executives in the company. An abductive research design was utilized. The company gained the leading position in the kitchen market in Finland by company purchases, and the company has been able to retain the position. Firstly the goal was to expand to retail market and, secondly, the company has maintained the balance of supply and demand by closing the purchased production units when needed. The simultaneous use of these two strategic goals is a kind of a new observation, and the strategy may be suitable only for market leaders. During the latter part of the research period the strategy of com-pany purchases has been abandoned and the leading position in the market has been main-tained by developing systematically business and marketing capability. In the business and marketing strategies the distribution channels and the brands have been emphasized. During the research period the company has almost totally abandoned the long distribution channels and started to use its own channels built and named after the main brands. These are A la Carte, Parma and Petra. At the moment, in the beginning of the 21st century, a new distribution channel, the concept of the Kitchen World, is being built in addition to the channels mentioned above. The management´s decision making and the implementation the decisions have been well-considered. The executives emphasized the valuing of the importance of the decisions dif-ferently except the two decisions named the most important ones, i.e., the decisions to start own production of the raw material and to concentrate the business only to one company. The executive staff has also succeeded in managing crisis and threats of bankruptcy, and the company has been managed profitable. During all the four terms of ownership: Puolimatka Corporation, the Hankkija/Novera Corporation, the ownership period of the "bank", and the Nobia Corporate the ownership direction and control has been somewhat different. All the owners have paid attention to economic issues. The direction of cash flows and investments was at its strongest during the Hankkija/Novera term. For the last owner Nobia the production and marketing of the kitchen interiors has been the core business, which thus has strengthened the business and marketing capabilities of the target company of this research. A common denominator during all the four terms of ownership has been owners' trust gained by the professional skills of the management of the target company. This has lead to greater independence of the management of the company and less owners´ direction. Keywords: leading position, marketing strategy, management decisions, acquisition, corporate governance

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Sään ennustamisessa tärkeä työväline on numeerinen säämalli, jossa ilmakehän tilan kuvaaminen perustuu niin sanottujen perusyhtälöiden ratkaisemiseen. Niiden avulla lasketaan tuulen nopeuden, ilmanpaineen, lämpötilan ja kosteuden muutokset pienin aika-askelin eteenpäin. Numeerinen säämalli tarvitsee lähtötiedokseen laadultaan hyviä havaintoja ilmakehän todellisesta tilasta. Joka vuorokausi kymmenet in-situ- ja kaukohavaintojärjestelmät tekevät havaintoja ilmakehästä sen pintakerroksesta ylärajaan asti. Pelkät havainnot eivät kuitenkaan riitä antamaan tarpeeksi tarkkoja lähtötietoja säämallille. Ongelman ratkaisu on data-assimilaatiojärjestelmä. Se yhdistää laatukontrollin läpikäyneen havaintotiedon ja mallitiedon, jota kutsutaan ennakkokentäksi, ja luo niiden avulla analyysin ilmakehän todellisesta tilasta. Havaintojärjestelmäkokeiden (OSE) avulla testataan havaintojärjestelmien vaikutuksia data-assimilaatiojärjestelmän tuottamien analyysien ja niistä tuotettujen sääennusteiden laatuun. OSE:n avulla selvitetään, kuinka hyvin saatavilla olevia havaintoja käytetään hyväksi, tai kannattaako jokin uusi havaintojärjestelmä ottaa mukaan operatiiviseen ennustusjärjestelmään. Tämän tutkielman aluksi tutustutaan lyhyesti numeerisiin säämalleihin, havaintojärjestelmiin ja dataassimilaatiojärjestelmiin, minkä jälkeen tehdään yleinen kirjallisuuskatsaus havaintojärjestelmäkokeiden suorittamisesta. Sen jälkeen keskitytään Doppler-säätutkan tuottamien tutkasäteen suuntaisten tuulen nopeushavaintojen hyödyntämiseen rajoitetun alueen HIRLAM-säämallissa, mitä on tutkittu viime vuosina Ilmatieteen laitoksessa (IL). Kaukohavaintojärjestelmien käyttö on lisääntynyt viime vuosien aikana kehittyneiden analyysimenetelmien ansiosta. Tavanomaisten in-situ- havaintojärjestelmien raju vähentäminen dataassimilaatiossa ei näytä kuitenkaan vielä olevan mahdollista. Kaukohavainnot ovat useiden OSE-kokeiden perusteella parantaneet analyysiä ja ennusteita erityisesti alueilla, joissa tavanomainen havaintoverkosto on harva. Tutkatuulihavaintojen on ajateltu tuovan parannuksia rajoitetun alueen säämalleihin, sillä niiden avulla saadaan tärkeää lisätietoa tuulen ageostrofisista ominaisuuksista. Sen johdosta pienen mittakaavan sääilmiöiden kuten meri- ja rinnetuulien ennustettavuuden toivotaan paranevan. IL:ssa on kehitetty tutkatuulihavaintojen käsittely- ja mallintamismenetelmiä, minkä jälkeen on suoritettu OSE Suomen tutkaverkoston tuulihavainnoilla aikavälille 1.-29.2.2008 HIRLAMin operatiiviselle 3D-VAR dataassimilaatiojärjestelmälle. Kyseisen OSE:n aineisto on saatu käyttöön tähän tutkielmaan. Kontrolliassimilaatiossa CON ovat mukana kaikki operatiiviset havaintojärjestelmät ja koeassimilaatioon RAD_ALL on syötetty myös tutkatuulihavainnot. Tässä tutkielmassa OSE:n tulokset todennetaan TEMP-tuulihavaintojen avulla tutkimalla ennakkokentän ja analyysin harhaa sekä satunnaisvirhettä. Tulosten perusteella tutkatuulihavainnot parantavat ennakkokenttää ja analyysiä erityisesti keskitroposfäärissä, mutta alatroposfäärissä vaikutus analyysiin on lähes neutraali. Koska tutkatuulihavainnot ulottuvat n. 4-6 km korkeuteen, ne eivät vaikuta ylätroposfäärin analyysiin. Tulokset eivät kuitenkaan ole tilastollisen testin perusteella tilastollisesti merkitseviä. Parhaimmillaan RAD_ALLassimilaation voidaan osoittaa olevan CON-assimilaatiota parempi 20% merkitsevyystasolla. Lopuksi suoritettu tapaustutkimus osoittaa, että tutkatuulihavaintojen vaikutus näkyy tuulen nopeuden analyysi-inkrementtikentässä sekä jossain määrin myös lyhyessä 12h pintapaine-ennusteessa Suomen alueella. Tapaustutkimuksen perusteella tutkatuulihavaintojen vaikutus analyysiin ja ennusteeseen näyttäisi olevan lähes neutraali. OSE:n toistaminen kesäkuukaudelle voisi olla hyödyllistä, koska talvella ei esiinny esimerkiksi merituulia. Tämän tutkielman tulosten perusteella tutkatuulihavaintojen käyttäminen HIRLAMin 3D-VAR assimilaatiojärjestelmässä on hyödyllistä. Avainsanat – Nyckelord – Keywords Havaintojärjestelmäkoe, data-assimilaatio, Doppler-tutkatuulihavainto Säilytyspaikka – Förvaringställe – Where deposited Kumpulan tiedekirjasto

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The present study examines citizen participation in local government and municipal democracy. Previous research has shown that the prerequisite for active citizenship lies in the opportunities available for local residents to determine which perspectives and planning needs are relevant. This research looks at whether the conception of knowledge employed in municipal planning allows for this kind of active role for local citizens. Methodologically the study employs an hermeneutic approach. The aim has been to identify various approaches steering the practice of municipal democracy. The theory behind the study comes from the assumption of the intersubjectivity of reality. Construing the rationality of one s own behaviour is seen as a prerequisite for meaningful action. In this context, criteria for the functionality of municipal democracy and the purpose of strengthening citizen participation are defined. The study is divided into two parts. Firstly, the purpose of participation and the opportunities for local residents to contribute is examined theoretically with reference to previous studies. The intention is to provide an overview of the Finnish cross-disciplinary debate on resident participation. This debate is reflected onto the prevailing views on changes in the municipal operating environment and modes of operation. In conclusion, a theoretical model is constructed to explain how the various modes of operation in regional municipalities affect the purpose of resident participation and the utilisation of information received through this participation. The second part of the study discusses the utilisation of this information and knowledge acquired through the participation of local residents and all those involved in political and administrative processes in municipalities. These first-hand reports are analysed using the model constructed earlier in the study. The goal is to understand how political and administrative practice affects opportunities for local residents to participate and contribute. The core of this analysis is based on the pragmatic conception of knowledge employed in municipal administration. The study argues that the normal practice of municipal administration does not support the systematic utilisation of local residents experience. This is caused by two interlinked factors: firstly, knowledge constructed through these practices requires that the knowledge is apolitical; secondly, arising from this there is confusion with regard to when during a planning process does information obtained from the public become relevant; in other words, what are the politics of knowledge? The study suggests that the solution is in the complementary concept of knowledge, which implicitly acknowledges the politics of knowledge. The complementary concept of knowledge would serve the politicisation of issues on the level of interpretations linked with social reality, an indispensable requirement for functional democracy. Keywords: participation, municipal democracy, knowledge base for planning, experiential knowledge

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A new rock mass classification scheme, the Host Rock Classification system (HRC-system) has been developed for evaluating the suitability of volumes of rock mass for the disposal of high-level nuclear waste in Precambrian crystalline bedrock. To support the development of the system, the requirements of host rock to be used for disposal have been studied in detail and the significance of the various rock mass properties have been examined. The HRC-system considers both the long-term safety of the repository and the constructability in the rock mass. The system is specific to the KBS-3V disposal concept and can be used only at sites that have been evaluated to be suitable at the site scale. By using the HRC-system, it is possible to identify potentially suitable volumes within the site at several different scales (repository, tunnel and canister scales). The selection of the classification parameters to be included in the HRC-system is based on an extensive study on the rock mass properties and their various influences on the long-term safety, the constructability and the layout and location of the repository. The parameters proposed for the classification at the repository scale include fracture zones, strength/stress ratio, hydraulic conductivity and the Groundwater Chemistry Index. The parameters proposed for the classification at the tunnel scale include hydraulic conductivity, Q´ and fracture zones and the parameters proposed for the classification at the canister scale include hydraulic conductivity, Q´, fracture zones, fracture width (aperture + filling) and fracture trace length. The parameter values will be used to determine the suitability classes for the volumes of rock to be classified. The HRC-system includes four suitability classes at the repository and tunnel scales and three suitability classes at the canister scale and the classification process is linked to several important decisions regarding the location and acceptability of many components of the repository at all three scales. The HRC-system is, thereby, one possible design tool that aids in locating the different repository components into volumes of host rock that are more suitable than others and that are considered to fulfil the fundamental requirements set for the repository host rock. The generic HRC-system, which is the main result of this work, is also adjusted to the site-specific properties of the Olkiluoto site in Finland and the classification procedure is demonstrated by a test classification using data from Olkiluoto. Keywords: host rock, classification, HRC-system, nuclear waste disposal, long-term safety, constructability, KBS-3V, crystalline bedrock, Olkiluoto