Thèse (D.R.Min.) -- Université du Québec à Chicoutimi, programme extensionné à l'Université du Québec à Montréal, 2001. / Bibliogr.: f. [155]-163. Document électronique également accessible en format PDF. CaQCU

Thèse 3 cycle--Géologie dynamique--Paris VI, 1975.

Studien syftar till att granska tidigare forskning om barnäktenskap genom en narrativ forskningsöversikt. Uppgiften för uppsatsen är att genomföra en första sammanställning av forskningsläget med följande frågor: vad orsakar barnäktenskap och vilka konsekvenser har barnäktenskap. För att begränsa studien behandlas endast referee bedömda tidskriftsartiklar som rör förhållandena i Afrika söder om Sahara. Forskningsöversikten domineras av verk som utforskar negativa konsekvenser av och orsaker till barnäktenskap på unga offer såväl som på familjer, samhället och ekonomin. De negativa effekterna av barnäktenskap på flickor utforskas genom fem sammanvävda teman i litteraturen som börjar med negativa effekter på flickors hälsa och fortsätter att undersöka negativa effekter på psykologisk utveckling, mänskliga rättigheter, flickors ekonomiska överlevnad samt samhällseffekter av barnäktenskap.

Speleothems (cave carbonate deposits) have been recognized as a multi-proxy paleoclimate archive. Variations in carbon and oxygen isotopes in speleothems can record past climate changes (e.g., temperature, rainfall and vegetation) under isotopic equilibrium conditions. However, non-climatic noises caused by in-cave processes may affect these stable isotope records under non-equilibrium isotopic conditions. The identification of equilibrium and non-equilibrium isotopic conditions in speleothems is still disputed in the speleothem research community; however, this is a prerequisite for the interpretation of carbon and oxygen isotope records in speleothems as paleoclimate proxies. In this Ph.D. thesis, a series of laboratory experiments under cave-analogue conditions were performed to simulate the formation of speleothems in natural caves. The results of these experiments demonstrate that stable isotope equilibrium in speleothems is achieved under slow carbonate precipitation in pool-like settings (pool carbonates). On the basis of these pool carbonates, equilibrium carbon and oxygen isotope fractionation factors between calcite and water (or DIC for carbon) were determined. Our experiments show larger carbon and oxygen isotope non-equilibrium fractionations between calcite and water (or DIC for carbon) in stalagmite-like settings (fast carbonate precipitate) than those determined in pool-like settings. The flow rate of drip water above the surface of stalagmite appears to control the magnitude of these non-equilibrium isotope effects which increase with decreasing the flow rate. Furthermore, a natural speleothem sample was examined as a paleoclimate archive in this thesis. The growth of a double stalagmite (WS-5d) in Wadi Sannur Cave from the Northeastern Sahara was used to infer the greening of the Sahara (intensive rainfall and vegetation). The U/Th dating in the WS-5d stalagmite suggests that greening conditions extended widely in the Sahara during the interglacial Marine Isotope Stages MIS 5.5, MIS 7.3, and the early MIS 9. Based upon oxygen isotope compositions from the WS-5d, we attributed the source of these greening periods to long-traveling rains from the Atlantic Ocean that were delivered via the West African monsoon system. Our study suggests that the two youngest greening periods were concurrent with the arrival of Homo sapiens in the Levant and an earlier possible change in human population at 244 ka, indicating a key role of the Sahara route in early human dispersal out of Africa. Finally, clumped isotope measurements (Δ47) on carbonate-derived CO2 have been shown to reflect the formation temperature of the carbonate minerals. The absolute Δ47 values of these isotopic measurements seem to be sensitive to the standardization methods (heated CO2 gases and water-equilibrated CO2 gases) that are used to normalize the raw Δ47 measurements. Neither the hypothetical base for the heated CO2 gas standardization method nor the theoretical base for the water-equilibrated CO2 gas standardization method has been experimentally tested. A series of CO2 gases were heated in pre-dehumidified quartz tubes to obtain equilibrium Δ47 values of these CO2 gases at temperature range of 50 – 1100 °C. Consequently, the first experimentally derived Δ47 – T calibration in a CO2 gas phase was proposed. This experimental calibration provides a validated base for the standardization of the raw Δ47 data. Moreover, heating CO2 in a pre-humidified quartz tube enables us to easily prepare a CO2 standard gas of a similar Δ47 value to the CO2 sample (i.e., similar Δ47 correction matrix). This will lead to an improvement in the correction scheme of the carbonate clumped isotope thermometry and reliably adjust the absolute Δ47 scale. / Thesis / Doctor of Philosophy (PhD)

Yes / This paper sums up the findings from the first comprehensive study on the United Nations Mission for the Referendum in Western Sahara. This research project explores the possibilities of using a Foucualtian analysis to look at the links between peacekeeping practice and Western policies of conflict containment in the Western Sahara with a view to enhancing UN conflict resolution capabilities.

Since 1992, the annual decline in the undernourished fraction of the world's population has been minimal (0.3%) making undernourishment one of the most pressing and alarming global issues. The FAO annually publishes a list of best and worst performing countries that respectively significantly decreased or increased the proportion of the population that was undernourished. Strikingly, seven out of ten global best performers and four out of ten global worst performers are located in Sub-Saharan Africa. This study therefore seeks to explore the variables affecting undernourishment rates, in an attempt to explain this variance. Six case studies hence explored three best performers (Angola, Chad and Ghana) and three worst performers (Botswana, Democratic Republic of Congo and Liberia) as the unit of analysis. Three clusters of variables were studied; natural shocks, agricultural production and economy. Changes in these variables were examined between 1992-2000 and Ragin's qualitative case study research strategy was applied to facilitate the analysis. The data indicated that the most influential variable was agricultural production. Furthermore, good governance leads to improvements in all three clusters of variables, whereas a civil war negatively effects all three clusters. Undernourishment proved to be a very complex and intertwined problem and similar research on a larger scale was recommended. / Master of Science

Yes / Despite more than two centuries of almost uninterrupted surveys and studies of Algerian lichenology, the history and lichen diversity of Algeria are still poorly understood. During the preparation of a forthcoming checklist of Algerian lichens it was considered necessary to provide the present historical overview of lichenological exploration of the country from 1799 to 2013, supported by a reasonably comprehensive annotated bibliography of 171 titles.

La thèse présentée ici actualise les anciennes données sur l’Acheuléen de l’Ahaggar, bien que ces données ne sont pas nombreuses et toutes datées du 20eme siècle. Mais pour reprendre une nouvelle ère de recherche sur le sujet, il est bien évident de les évoquer. Malgré les fructueuses découvertes dans de nombreux sites paléolithiques inférieurs, dans l’Ahaggar, aucun intérêt scientifique n’a été apporté, notamment aux nombreuses collections lithiques interposées dans plusieurs laboratoires de recherches scientifiques. Le nouveau site « Téhéntawek » Acheuléen découvert dans la région d’Idelès, au cœur du Sahara central, dans l’Ahaggar et fouillé avec des nouvelles méthodes pédagogiques instaurées dans la préhistoire actuelle, nous a livré en 2008 et 2010 un matériel lithique intéressant et très représentatif de l’industrie acheuléenne. Ces démarches sont considérées comme rénovatrices de la préhistoire saharienne. La prospection appropriée et adéquate à l’environnement, l’adaptation du travail du terrain au contexte rocheux de la région de l’Ahaggar, nous ont permis de reconsidérer le terrain saharien. L’étude technologique du matériel lithique a fourni une diversité d’outils et une coexisté de chopper, biface et hachereau, nombreux sont les éclats bruts, très compatibles avec les nucléus. Les matières premières lithiques utilisées pour le façonnage sont locales. Les résultats des analyses réalisées, sur les sédiments prélevés ont fourni de nouvelles données, notamment une ouverture sur le paléoenvironnement de l’Ahaggar. Ainsi le site Téhéntawek nous a offert des informations pertinentes sur la maitrise de l’homme dans cet environnement actuellement saharien. / The thesis presented here updates the old data on the Acheulian of the Ahaggar, although these date are few in number and all dated 20th century. But it is obvious to mention them to borrow a new er of research on the subject. Despite the fruitful discoveries in many lower Palaeolithic sites in the Ahaggar, no scientific interest have been provided to many lithic collections interposed in several laboratories for scientific research. The new site “Téhéntawek” Acheulean discovered in the region of Idelès in the central Sahara of the Ahaggar and excavated with new pedagogical methods introduced in the present prehistory, has delivered in 2008 and 2010 an interesting lithic materials representative of the Acheulian industry. These approaches are considered renovative of the Saharan prehistory. The appropriate and adequate environmental of exploration, the adaptation of work to the rocky terrain of the Ahaggar region, have allowed us to reconsider the Saharan terrain. The study of lithic technology has provided a variety of tools and coexisted chopper, biface and cleaver, many raw chips, very consistent with the nucleus. Lithic raw materials used for shaping are local. The results of analyses on the sediments provided new data, including an opening on the paleoenvironment of the Ahaggar. Thus Téhéntawek site offered us with relevant information on the mastery of man in this currently Saharan environment.

La topographie de l’Afrique du Nord est marquée en domaine intraplaque par des bombements topographiques importants, associés à du magmatisme cénozoïque. Le Bouclier Touareg, un de ces bombements, est constitué d’un socle précambrien structuré à l’orogénèse panafricaine et culminant à plus de 2400 m d’altitude. Les séries paléozoïques affleurent actuellement sous forme de cuestas autour de ce bombement topographique. Localement, des témoins sédimentaires d’âge présumé crétacé, en discordance sur le socle précambrien, traduisent l’affleurement de celui-ci au Mésozoïque. Le volcanisme cénozoïque, qui se met également en place sur le socle, est actif entre 35 Ma et aujourd’hui. Afin de mieux contraindre l’évolution du Bouclier Touareg durant le Phanérozoïque, nous avons mené deux études : des travaux de modélisation géophysique, et une étude de thermochronologie basse température. L’étude géophysique a consisté en la modélisation de quatre profils longue distance permettant d’imager la structure lithosphérique. Nous avons montré que le bombement du Hoggar est actuellement soutenu par un important amincissement lithosphérique. En outre, nous avons estimé que sans cet amincissement, la topographie serait négative : le bassin ainsi reconstitué avant amincissement de la lithosphère aurait permis le dépôt d’une couverture sédimentaire d’épaisseur plurikilométrique. L’étude de thermochronologie basse température s’est portée sur deux méthodes : les analyses de traces de fission sur apatite, et les analyses (U-Th)/He sur apatite. Les analyses (U-Th)/He ont montré que le socle du Bouclier Touareg, avant d’avoir subi une importante exhumation à l’Eocène Supérieur, étant enseveli sous une couverture sédimentaire et chauffé à approximativement ~80°C. Les analyses de traces de fission ont permis de préciser que cette phase de chauffe, probablement sous couverture sédimentaire, du Bouclier Touareg a eu lieu entre 100 et 50 Ma. Ainsi, le bombement du Hoggar constituait probablement un bassin sédimentaire de grande dimension au cours du Crétacé supérieur/Paléocène. Ces résultats nous ont permis de discuter des mécanismes géodynamiques possiblement actifs durant le Cénozoïque. Nous proposons que le bombement actuel du Bouclier Touareg, ainsi que son magmatisme, soient liés à des perturbations thermiques des parties superficielles de l’asthénosphère. Ces perturbations seraient induites par d’importantes variations d’épaisseur de la lithosphère saharienne, et pourraient expliquer la présence d’autres bombements en Afrique du Nord. / The North-African intraplate topography is underlined by massive topographic swells associated with Cenozoic volcanism. The Tuareg Shield, which is one of these swells, consists of Precambrian basement which has been structured by the Pan-African orogeny and reaches currently an altitude of 2400 m. The Paleozoic sedimentary series are outcropping as important cuestas surrounding the topographic swell. Locally, some Mesozoic sedimentary remnants, lying unconformably over the basement, testify of its exposure during the Mesozoic. The Cenozoic volcanism, which is also taking place on the basement, shows ages from 35 Ma to Quaternary. In order to improve the knowledge of the Phanerozoic evolution of the Tuareg Shield, we performed two separated studies: geophysical modelling works, and a low temperature thermochronology study. The geophysical study consisted of the modelling of four long-distance profiles allowing imaging the lithospheric structure. We have shown that the Tuareg Shield swell is currently sustained by a strong lithospheric thinning. Moreover, we have estimated that without this thinning, the topography would be negative and that such basin, prior to thinning, would have allowed the deposition of a plurikilometric sedimentary cover. The low temperature thermochronological study has focused on two methods: apatite fission-track analysis, and apatite (U-Th)/He analysis. The latter shown that the Tuareg Shield, before an important Late Eocene exhumation, was buried under a sedimentary cover and heated at ~80°C. The fission-track analyses have shown that this heating stage of the Tuareg Shield, related to burying, occurred from 100 and 50 Ma. Thus, the Tuareg Shield was probably a wide scale sedimentary basin during the Upper Cretaceous – Paleocene. These results allowed us to discuss the geodynamic mechanisms potentially active during the Cenozoic. We proposed that the current doming of the Tuareg Shield, as well as its volcanism, were related to thermal perturbations of the shallower levels of the asthenosphere. These instabilities would have been generated by strong Saharan lithospheric thickness variations, and could explain the presence of others swells in North Africa.

In the wake of HIV and AIDS in Africa, culture has been identified as central to HIV prevention, care, and support. Therefore, scholars have argued that HIV intervention in communities should focus on cultural practices rather than just individual behaviour. Researchers have also taken note of the interconnectedness between religion and culture in Africa. Therefore the African theologian, Mercy Oduyoye, proposed the term ‘religioculture.’ In the light of this connection, it has become crucial to examine not just cultural practices but the response of religion to cultural practices in the context of HIV. Given that Zambia is a Christian country, this qualitative empirical study sought to examine the response of a church, the United Church of Zambia (UCZ), to traditional marriage practices that I consider to be harmful in the context of HIV. Traditional marriage practices such as child marriage and widowhood inheritance were analysed through gendered theological perspectives. The study was located in the United Church of Zambia in the towns of Mufulira and Kitwe in the Copperbelt Province of Zambia. The reason for choosing the practices of widowhood inheritance and child marriage as the areas of focus was twofold: first, throughout history and in the current context, the church and society’s perception of these two practices has been ambiguous. Depending on the time and event in history, the practices were seen as either a norm or a problem. In this study, I have questioned the extent to which this historical ambiguity towards these traditional marriage practices has contributed to the way in which the church today is responding to these culture practices. The second reason for choosing these two marriage practices was to highlight how the institution of marriage has been challenged in the context of HIV and AIDS. When marriage ceases to be a safe practice for couples, how should the church respond to the harmful cultural practices associated with marriage, especially in the context of HIV and AIDS? The question that this study posed, therefore, was: What role has the United Church of Zambia played in either promoting or discouraging harmful marriage practices in the context of HIV and AIDS? The methodology used to answer this question included: semi- structured interviews, openended in-depth interviews, Contextual Bible Study, and focus group discussions as forms of data collection from: church leaders, lay people, widows, girls involved in child marriage, and members of the Marriage Guidance Committee. Thereafter, the data was thematically ii analysed using the theory of African feminist cultural hermeneutics. The study is divided into eight chapters, each chapter answers one of the objectives of the study. Through the use of the tools for data collection stated above, the study drew a number of conclusions. Firstly, it was established that indeed child marriage and widowhood inheritance are contributing factors to the spread of HIV. Secondly, the Marriage Guidance Programme of the United Church of Zambia was identified as a point of entry in re-examining the theology of marriage that is contextual and holistic in the United Church of Zambia. Thirdly, the church’s ambivalence with regard to harmful marriage practices in the context of HIV and AIDS was attributed to people’s belief systems about their cultures which are embedded in their worldviews. Overall, the study has shown that there is a need for an analysis of culture within the church which can enable it to respond to harmful cultural practices in the context of HIV. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.