57 resultados para Culture diversity


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A short article summarizing the most visible streams of Mexican music along the last century. Special attention is paid to the intellectual and idiosyncratic components which are considered as elements of authenticity in Mexican culture.

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Agri-environmental schemes have so far resulted in only minor positive implications for the biodiversity of agricultural environments, in contrast to what has been expected. Land-use intensification has decreased landscape heterogeneity and the amount of semi-natural habitats. Field margins are uncultivated areas of permanent vegetation located adjacent to fields. Since the number of these habitats is high, investing in their quality may result in more diverse agricultural landscapes. Field margins can be considered as multifunctional habitats providing agronomic, environmental and wildlife services. This thesis aimed at examining the plant communities of different types of field margin habitats and the factors affecting their species diversity and composition. The importance of edaphic, spatial and management factors was studied on regional, landscape and habitat scales. Vegetation surveys were conducted on regional and landscape scales and a field experiment on cutting management was conducted on a habitat scale. In field margin plant communities, species appeared to be indicators of high or intermediate soil fertility and moist soil conditions. The plant species diversity found was rather low, compared with most species-rich agricultural habitats in Finland, such as dry meadows. Among regions, land-use history, main production line, natural species and human induced distribution, climate and edaphic factors were elements inducing differences in species composition. The lowest regional species diversity of field margins was related to intensive and long-term cereal production. Management by cutting and removal or grazing had a positive effect on plant species diversity. The positive effect of cutting and removal on species richness was also dependent on the adjacent source of colonizing species. Therefore, in species-poor habitats and landscapes, establishment of margins with diverse seed mixtures can be recommended for enhancing the development of species richness. However, seed mixtures should include only native species preferably local origin. Management by cutting once a year for 5 years did not result in a decline in dominance of a harmful weed species, Elymus repens, showing that E. repens probably needs cutting more frequently than once per year. Agri-environmental schemes should include long-term contracts with farmers for the establishment, and management by cutting and removal or grazing, of field margins that are several metres wide. In such schemes, the timing and frequency of management should be planned so as not to harm other taxa, such as the insects and birds that are dependent on these habitats. All accidental herbicide drifts to field margins should be avoided when spraying the cultivated area to minimize the negative effects of sprayings on vegetation. The harmful effects of herbicides can be avoided by organic farming methods.

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Campylobacter, mainly Campylobacter jejuni and C. coli, are worldwide recognized as a major cause of bacterial food-borne gastroenteritis. Epidemiological studies have shown handling or eating of poultry to be significant risk factors for human infections. Campylobacter contamination can occur at all stages of a poultry meat production cycle. The aim of this thesis was to study the occurrence and diversity of Campylobacter in broiler and turkey production in Finland. In summer 1999, 2.9 % of slaughtered broiler flocks were Campylobacter-positive. From the isolated strains 94 % were C. jejuni and 6% were C. coli. During years 2005-2006 one turkey parent flock, the hatchery, six different commercial turkey farms and different stages of the slaughterhouse were monitored during one and the half year. No Campylobacter were detected in either of the samples from the turkey parent flock or from the hatchery using the culture method. Instead PCR detected DNA of Campylobacter from the turkey parent flock and samples from the hatchery. Six out of 12 commercial turkey flocks were found negative at the farm level but only two of those were negative at slaughter. Campylobacter-positive samples within the flock at slaughter were detected between 0% and 94% with evisceration and chilling water being the most critical stages for contamination. All of Campylobacter isolates were shown to be C. jejuni. Campylobacter-positive turkey flocks were colonized by a limited number of Campylobacter genotypes both at the farm and slaughter level. In conclusion, in our first study in 1999 a low prevalence of Campylobacter in Finnish broiler flocks was detected and it has remained at a low level during the study period until the present. In the turkey meat production, we found that flocks which were negative at the farm became contaminated with Campylobacter at the slaughter process. These results suggest that proper and efficient cleaning and disinfection of slaughter and processing premises are needed to avoid cross-contamination. Prevention of colonization at the farm by a high level of biosecurity control and hygiene may be one of the most efficient ways to reduce the amount of Campylobacter-positive poultry meat in Finland. With a persistent low level of Campylobacter-positive flocks, it could be speculated that the use of logistic slaughtering, according to Campylobacter status at farm, might have be advantageous in reducing Campylobacter contamination of retail poultry products. However, the significance of the domestic poultry meat for human campylobacteriosis in Finland should be evaluated.

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The aim of this thesis is to examine migration of educated Dominicans in light of global processes. Current global developments have resulted in increasingly global movements of people, yet people tend to come from certain places in large numbers rather than others. At the same time, international migration is increasingly selective, which shows in the disproportional number of educated migrants. This study discovers individual and societal motivations that explain why young educated Dominicans decide to migrate and return. The theoretical framework of this thesis underlines that migration is a dynamic process rooted in other global developments. Migratory movements should be seen as a result of interacting macro- and microstructures, which are linked by a number of intermediate mechanisms, meso-structures. The way individuals perceive opportunity structures concretises the way global developments mediate to the micro-level. The case of the Dominican Republic shows that there is a diversity of local responses to the world system, as Dominicans have produced their own unique historical responses to global changes. The thesis explains that Dominican migration is importantly conditioned by socioeconomic and educational background. Migration is more accessible for the educated middle class, because of the availability of better resources. Educated migrants also seem less likely to rely on networks to organize their migrations. The role of networks in migration differs by socioeconomic background on the one hand, and by the specific connections each individual has to current and previous migrants on the other hand. The personal and cultural values of the migrant are also pivotal. The central argument of this thesis is that a veritable culture of migration has evolved in the Dominican Republic. The actual economic, political and social circumstances have led many Dominicans to believe that there are better opportunities elsewhere. The globalisation of certain expectations on the one hand, and the development of the specifically Dominican feeling of ‘externalism’ on the other, have for their part given rise to the Dominican culture of migration. The study also suggests that the current Dominican development model encourages migration. Besides global structures, local structures are found to ve pivotal in determining how global processes are materialised in a specific place. The research for this thesis was conducted by using qualitative methodology. The focus of this thesis was on thematic interviews that reveal the subject’s point of view and give a fuller understanding of migration and mobility of the educated. The data was mainly collected during a field research phase in Santo Domingo, the Dominican Republic in December 2009 and January 2010. The principal material consists of ten thematic interviews held with educated Dominican current or former migrants. Four expert interviews, relevant empirical data, theoretical literature and newspaper articles were also comprehensively used.

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Calendula officinalis is grown widely as an ornamental plant across Europe. It belongs to the large. Asteraceae family. In this study, the aim was to explore the possibilities to use Calendula officinalis as a new model organism for flower development and secondary mechanism studies in Asteraceae. Tissue culture of Calendula officinalis was established using nine different cultivars. Murashige & Skoog (MS) medium with four different combinations of plant growth regulators were tested. Of all these combinations, the medium containing 1mg/l BAP, 0.1 mg/l IAA, and 1mg/l Zeatin achieved highest frequency of adventitious shoot regeneration from hypocotyl and cotyledon explants. Virus-induced gene silencing is a recent developed genetic tool for charactering the gene functions in plants, and extends the range of host plants that are not accessible for Agrobacterium transformation. Here, tobacco rattle virus (TRV)-based VIGS technique was tested in calendula (cv. Single Orange). We used TRV carrying Gerbera hybrid phytoene desaturase (PDS) gene fragment to induce PDS silencing in calendula. Vacuum infiltration and syringe infiltration methods both resulted in photo-bleaching phenotypes in leaves, bracts and petals. Loss-of-function phenotypes occurred on calendula 13 days post-infiltration. In conclusion, the data indicates that calendula explants can be regenerated through tissue culture which is a prerequisite for development of stable transformation methods. However, further optimization is still needed to improve the frequency. In addition, VIGS was applied to silence PDS marker gene expression indicating that this method has potential for gene functional studies in future.

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Epidemiological studies have shown an elevation in the incidence of asthma, allergic symptoms and respiratory infections among people living or working in buildings with moisture and mould problems. Microbial growth is suspected to have a key role, since the severity of microbial contamination and symptoms show a positive correlation, while the removal of contaminated materials relieves the symptoms. However, the cause-and-effect relationship has not been well established and knowledge of the causative agents is incomplete. The present consensus of indoor microbes relies on culture-based methods. Microbial cultivation and identification is known to provide qualitatively and quantitatively biased results, which is suspected to be one of the reasons behind the often inconsistent findings between objectively measured microbiological attributes and health. In the present study the indoor microbial communities were assessed using culture-independent, DNA based methods. Fungal and bacterial diversity was determined by amplifying and sequencing the nucITS- and16S-gene regions, correspondingly. In addition, the cell equivalent numbers of 69 mould species or groups were determined by quantitative PCR (qPCR). The results from molecular analyses were compared with results obtained using traditional plate cultivation for fungi. Using DNA-based tools, the indoor microbial diversity was found to be consistently higher and taxonomically wider than viable diversity. The dominant sequence types of fungi, and also of bacteria were mainly affiliated with well-known microbial species. However, in each building they were accompanied by various rare, uncultivable and unknown species. In both moisture-damaged and undamaged buildings the dominant fungal sequence phylotypes were affiliated with the classes Dothideomycetes (mould-like filamentous ascomycetes); Agaricomycetes (mushroom- and polypore-like filamentous basidiomycetes); Urediniomycetes (rust-like basidiomycetes); Tremellomycetes and the family Malasseziales (both yeast-like basidiomycetes). The most probable source for the majority of fungal types was the outdoor environment. In contrast, the dominant bacterial phylotypes in both damaged and undamaged buildings were affiliated with human-associated members within the phyla Actinobacteria and Firmicutes. Indications of elevated fungal diversity within potentially moisture-damage-associated fungal groups were recorded in two of the damaged buildings, while one of the buildings was characterized by an abundance of members of the Penicillium chrysogenum and P. commune species complexes. However, due to the small sample number and strong normal variation firm conclusions concerning the effect of moisture damage on the species diversity could not be made. The fungal communities in dust samples showed seasonal variation, which reflected the seasonal fluctuation of outdoor fungi. Seasonal variation of bacterial communities was less clear but to some extent attributable to the outdoor sources as well. The comparison of methods showed that clone library sequencing was a feasible method for describing the total microbial diversity, indicated a moderate quantitative correlation between sequencing and qPCR results and confirmed that culture based methods give both a qualitative and quantitative underestimate of microbial diversity in the indoor environment. However, certain important indoor fungi such as Penicillium spp. were clearly underrepresented in the sequence material, probably due to their physiological and genetic properties. Species specific qPCR was a more efficient and sensitive method for detecting and quantitating individual species than sequencing, but in order to exploit the full advantage of the method in building investigations more information is needed about the microbial species growing on damaged materials. In the present study, a new method was also developed for enhanced screening of the marker gene clone libraries. The suitability of the screening method to different kinds of microbial environments including biowaste compost material and indoor settled dusts was evaluated. The usability was found to be restricted to environments that support the growth and subsequent dominance of a small number microbial species, such as compost material.

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The purpose of this study is to define how Helsinki has been presented in the pictures of tourist brochures and how their illustration has changed over time. Attention is also paid to the values and meanings that the pictures mediate, as well as their historical and societal connections. The pictures are approached as representations selectively interpreting and illustrating the reality of Helsinki, while constructing mental images of it. An iconological framework structures the study. It proceeds from the description and classification of the physical features towards an analysis of time- and culture-specific meanings. The emergence of meanings and their historical and cultural underpinnings are examined from the perspectives of humanistic geography, semiotics and constructionism. In the analysis attention is paid to the discourses, myths and ideologies that underlie the representations. Information on the physical features of the pictures and their changes is collected with a content analysis. The classified data consists of 1377 photographs. These pictures are collected from 75 tourist brochures of Helsinki that have been published between 1895 and 2005. The deeper meanings of the pictures are studied qualitatively, by paying attention to the mental images that the content elements and visual effects evoke. Research studies, contemporary literature and the texts of the tourist brochures are utilised in the interpretation of the meanings. There has been a permanent core to objects of the pictures during the entire study period. It has consisted mainly of sights that are located close to the Senate and Market Squares. In addition, marine elements have been popular. The area of Helsinki represented in the brochures has extended from the Senate Square towards Töölö Bay. Pictures of monumental buildings and statues have been complemented with snapshots and portraits. In the beginning of the 20th century, brochures were mainly produced for the travelling, educated elite. The style of the pictures was declaratory and educative. They aimed at medating an objective image of the reality that prevailed in Helsinki. In practice, the pictures were connected to a patriotic ideology and the corresponding myth of Finnishness. In the second half of the 20th century the improvement of the standard of living led to a democratisation of consumers and an increase in the tourism demand. Local culture and the everyday life of "ordinary" people became popular themes in the pictures. A new welfare ideology manifested itself in the people of the local residential areas, for instance. The increase in the cultural diversity has led to the recognition of new target groups, expecially since the 1980s. The human figures in the pictures have started to function as objects of identification and a means of constructing mental images. A pronounced emphasis on experience and individuality in the illustration of the tourist brochures mirrors the post-modern change and a new ideology based on consumption. The construction and consumption of the pictures in the tourist brochures is governed by the conventions of representation and interpretaion that are typical of the genre of tourist brochures. The pictures emphasize the perceived positive characteristics of Helsinki and thus construct a skewed view of the reality. However, consumers can knowingly use the pictures as a means of dreaming and detaching themselves from their everyday reality.