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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Postglacial Population History of the Common Shrew (<i>Sorex araneus</i>) in Fennoscandia : Molekylära studier av återkolonisation, könsbundet genflöde och kromosomrasbildning. / Den vanliga näbbmusens (<i>Sorex araneus</i>) postglaciala populationshistoria i Fennoskandien : Molekylära studier av återkolonisation, könsbundet genflöde och kromosomrasbildning.

Andersson, Anna-Carin January 2004 (has links)
<p>The common shrew, <i>Sorex araneus</i>, has one of the most variable karyotypes among mammals, displaying numerous chromosomes races throughout its distribution, which can be categorized into different karyotypic groups. The objective of this thesis was to examine the postglacial population history of Fennoscandian common shrews using autosomal microsatellites, mitochondrial DNA (mtDNA) and a Y chromosome specific microsatellite (L8Y).</p><p>Autosomal microsatellites and mtDNA revealed weak genetic structure over a hybrid zone between the karyotypically divergent Northern and Western karyotypic groups. However, the genetic structure displayed by the Y chromosome microsatellite was orders of magnitude higher. Hence, considerable chromosomal differences between the groups do not prevent female gene flow, while male gene flow is reduced (cf. Haldane's rule). Further, the results suggest that the Haldane effect may be caused by the chromosomal differences between the karyotypic groups.</p><p>No mtDNA differentiation was observed either between chromosome races or between the Northern and Western karyotypic groups in Fennoscandia. The combined pattern of karyotypic and mtDNA variation of Fennoscandian common shrews, suggest bi-directional postglacial recolonisation from a single refugium in Europe. The variation of the Y-linked microsatellite supported this conclusion. In contrast, significant mtDNA structure, discordant with the karyotypic variation, revealed that common shrews in southern Finland belong to a different lineage than remaining Fennoscandian regions, implying postglacial recolonisation from a different source.</p><p>MtDNA variation of the chromosome races in Sweden supports the hypothesis that three races of the Western karyotypic group have been formed through whole arm reciprocal translocations (WARTs), as suggested by their mutual karyotypic variation. The variation of the molecular markers supports the theory of rapid karyotypic evolution in the common shrew.</p>
2

Postglacial Population History of the Common Shrew (Sorex araneus) in Fennoscandia : Molekylära studier av återkolonisation, könsbundet genflöde och kromosomrasbildning. / Den vanliga näbbmusens (Sorex araneus) postglaciala populationshistoria i Fennoskandien : Molekylära studier av återkolonisation, könsbundet genflöde och kromosomrasbildning.

Andersson, Anna-Carin January 2004 (has links)
The common shrew, Sorex araneus, has one of the most variable karyotypes among mammals, displaying numerous chromosomes races throughout its distribution, which can be categorized into different karyotypic groups. The objective of this thesis was to examine the postglacial population history of Fennoscandian common shrews using autosomal microsatellites, mitochondrial DNA (mtDNA) and a Y chromosome specific microsatellite (L8Y). Autosomal microsatellites and mtDNA revealed weak genetic structure over a hybrid zone between the karyotypically divergent Northern and Western karyotypic groups. However, the genetic structure displayed by the Y chromosome microsatellite was orders of magnitude higher. Hence, considerable chromosomal differences between the groups do not prevent female gene flow, while male gene flow is reduced (cf. Haldane's rule). Further, the results suggest that the Haldane effect may be caused by the chromosomal differences between the karyotypic groups. No mtDNA differentiation was observed either between chromosome races or between the Northern and Western karyotypic groups in Fennoscandia. The combined pattern of karyotypic and mtDNA variation of Fennoscandian common shrews, suggest bi-directional postglacial recolonisation from a single refugium in Europe. The variation of the Y-linked microsatellite supported this conclusion. In contrast, significant mtDNA structure, discordant with the karyotypic variation, revealed that common shrews in southern Finland belong to a different lineage than remaining Fennoscandian regions, implying postglacial recolonisation from a different source. MtDNA variation of the chromosome races in Sweden supports the hypothesis that three races of the Western karyotypic group have been formed through whole arm reciprocal translocations (WARTs), as suggested by their mutual karyotypic variation. The variation of the molecular markers supports the theory of rapid karyotypic evolution in the common shrew.
3

The hyporeic zone as a primary source of invertebrate community resilience in intermittent alluvial rivers : evidence from field and mesocosm experiments / La zone hyporhéique favorise la résilience des communautés d'invertébrés dans les rivières alluviales intermittentes : expériences de terrain et mésocosmes en laboratoire

Vander Vorste, Ross 10 December 2015 (has links)
Un paradigme émergent prédit que les perturbations influencent les processus qui déterminent l'organisation des communautés. L'assèchement des rivières (disparition complète d'eau de surface pour une durée déterminée) est une perturbation naturelle affectant les cours d'eau dans de nombreuses régions du monde. De plus en plus de cours d'eau pérenne s'assèchent en réponse aux changements globaux. Toutefois, l'effet de ces assèchements sur les communautés aquatiques et les processus impliqués dans leur résilience restent mal quantifié et mal compris. A travers quatre études allant de suivis de terrain à des expérimentations in-situ et des mésocosmes en laboratoire, une résilience exceptionnelle des communautés d'invertébrés a été mesurée dans huit rivières alluviales. La zone hyporhéique semble être la principale source de recolonisation expliquant la forte résilience de ces communautés. En laboratoire, l'augmentation de la température et de la compétition intra-spécifique entraine une migration de Gammarus pulex dans la zone hyporhéique. L'augmentation de la profondeur de la zone hyporhéique lors d'assèchements pourrait réduire la résilience et avoir des effets sur les fonctions de l'écosystème (décomposition de litière). Ces résultats montrent que les assèchements n'ont pas toujours des effets sévères sur les communautés d'invertébrés des rivières alluviales qui semblent même très résilientes. La zone hyporhéique joue un rôle primordial dans la résilience des communautés des cours d'eau. Un accent devrait être mis sur la protection de la zone hyporhéique dans les rivières alluviales afin de préserver cette capacité de résilience face aux changements globaux / Understanding community response to disturbance is essential to identifying processes that determine their assembly and to predicting the future effects of climate change on biodiversity and ecosystem functions. Drying (complete loss of surface water) is a natural disturbance affecting 50% of rivers worldwide and is occurring more in perennial rivers due to climate change. However, its effects on aquatic invertebrate communities and the underlying processes contributing to their resilience (i.e. return to pre-drying or undisturbed levels) have not been well quantified. Using 4 congruous field and mesocosm experiments to quantify community resilience and identify its primary sources in environmentally harsh alluvial rivers. First, I found communities in 8 alluvial rivers were highly resilient to moderate and severe drying. Second, I showed that the hyporheic zone (saturated interstitial sediments) can be the primary source of colonists, promoting high community resilience. Third, I found high water temperature and intraspecific competition caused Gammarus pulex, a common benthic detritivore, to migrate into the hyporheic zone. Fourth, I found increasing depth to the water table diminished the hyporheic zone’s role as a source of colonists by reducing survival of G. pulex. My results support an emerging concept that harsh ecosystems are highly resilient and indicate that the effects of drying on biodiversity and ecosystem functions could vary across river systems. In alluvial rivers, the hyporheic zone can contribute strongly to community resilience and management should focus on protecting and restoring vertical connectivity to maximize resilience to climate change
4

Pitfalls of national development and reconstruction : an ethical appraisal of socio-economic transformation in post-war Mozambique

Matsinhe, David Mário 06 1900 (has links)
Mozambique is undergoing intensive socio-economic reforms to reconstruct war damages and develop the nation. The reforms consist of economic liberalisation through structural adjustment and monetarist economic stabilisation, e.g. government withdrawal from economic activities, privatisation, deregulation, reduction of tariff levels on imports and tax on investments, cuts of expenditure on social services, restrictive credit system, focus on monetarism, increased taxation on individual income, etc. The nature of these reforms, on the surface, leads to morally questionable conditions. There is social chaos and disintegration, high indices of corruption, subtle recolonisation, decline of civil services, etc. At the bottom lie the market ethics and fundamentalist theological discourse by dint of which the World Bank and the International Monetary Fund deny historical consciousness, lack institutional memory, vest themselves with unquestionable international authority, dictate and impose policies without accountability for the social consequences. If there is any hope for Mozambicans, it lies in development ethics which relies heavily on the liberation motif, historical consciousness, and African Heritage. / Philosophy, Practical & Systematic Theology / M. Th. (Theological Ethics)
5

'More than America': some New Zealand responses to American culture in the mid-twentieth century.

Whitcher, Gary Frederick January 2011 (has links)
This thesis focuses on a transformational but disregarded period in New Zealand’s twentieth century history, the era from the arrival of the Marines in 1942 to the arrival of Rock Around the Clock in 1956. It examines one of the chief agents in this metamorphosis: the impact of American culture. During this era the crucial conduits of that culture were movies, music and comics. The aims of my thesis are threefold: to explore how New Zealanders responded to this cultural trinity, determine the key features of their reactions and assess their significance. The perceived modernity and alterity of Hollywood movies, musical genres such as swing, and the content and presentation of American comics and ‘pulps’, became the sources of heated debate during the midcentury. Many New Zealanders admired what they perceived as the exuberance, variety and style of such American media. They also applauded the willingness of the cultural triptych to appropriate visual, textual and musical forms and styles without respect for the traditional classifications of cultural merit. Such perceived standards were based on the privileged judgements of cultural arbiters drawn from members of New Zealand’s educational and civic elites. Key figures within these elites insisted that American culture was ‘low’, inferior and commodified, threatening the dominance of a sacrosanct, traditional ‘high’culture. Many of them also maintained that these American cultural imports endangered both the traditionally British nature of our cultural heritage, and New Zealand’s distinctively ‘British’ identity. Many of these complaints enfolded deeper objections to American movies, music and literary forms exemplified by comics and pulps. Significant intellectual and civic figures portrayed these cultural modes as pernicious and malignant, because they were allegedly the product of malignant African-American, Jewish and capitalist sources, which threatened to poison the cultural and social values of New Zealanders, especially the young. In order to justify such attitudes, these influential cultural guardians portrayed the general public as an essentially immature, susceptible, unthinking and puritanical mass. Accordingly, this public, supposedly ignorant of the dangers posed by American culture, required the intervention and protection of members of this elite. Responses to these potent expressions of American culture provide focal points which both illuminate and reflect wider social, political and ideological controversies within midcentury New Zealand. Not only were these reactions part of a process of comprehension and negotiation of new aesthetic styles and media modes. They also represent an arena of public and intellectual contention whose significance has been neglected or under-valued. New Zealanders’ attitudes towards the new cinematic, literary and musical elements of American culture occurred within a rich and revealing socio-political and ideological context. When we comment on that culture we reveal significant features of our own national and cultural selves.
6

Pitfalls of national development and reconstruction : an ethical appraisal of socio-economic transformation in post-war Mozambique

Matsinhe, David Mário 06 1900 (has links)
Mozambique is undergoing intensive socio-economic reforms to reconstruct war damages and develop the nation. The reforms consist of economic liberalisation through structural adjustment and monetarist economic stabilisation, e.g. government withdrawal from economic activities, privatisation, deregulation, reduction of tariff levels on imports and tax on investments, cuts of expenditure on social services, restrictive credit system, focus on monetarism, increased taxation on individual income, etc. The nature of these reforms, on the surface, leads to morally questionable conditions. There is social chaos and disintegration, high indices of corruption, subtle recolonisation, decline of civil services, etc. At the bottom lie the market ethics and fundamentalist theological discourse by dint of which the World Bank and the International Monetary Fund deny historical consciousness, lack institutional memory, vest themselves with unquestionable international authority, dictate and impose policies without accountability for the social consequences. If there is any hope for Mozambicans, it lies in development ethics which relies heavily on the liberation motif, historical consciousness, and African Heritage. / Philosophy, Practical and Systematic Theology / M. Th. (Theological Ethics)

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