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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.
301

Space-time modelling of seasonal soil moisture for improved crop production – the case of the Guinea savannah region, Ghana

Nketia, Kwabena Abrefa 03 July 2020 (has links)
No description available.
302

Les nuages de mi-niveau en Afrique de l'Ouest : observation, caractérisation, modélisation / Mid-level clouds in West Africa : observation, characterisation, modelling

Bourgeois, Elsa 07 December 2017 (has links)
Les nuages jouent un rôle important dans le cycle de l'eau et de l'énergie au sein de l'atmosphère. De plus, ils représentent l'une des principales sources d'incertitudes dans les projections des modèles de climat en raison notamment de la difficulté à paramétrer les processus qui leurs sont associés ainsi que leurs interactions avec l'environnement. Dans cette thèse nous étudions les nuages de mi-niveau qui ont été beaucoup moins étudiés que les nuages bas et les nuages hauts, en se focalisant sur l’Afrique de l'Ouest. L'Afrique de l'Ouest se caractérise par une forte saisonnalité des précipitations survenant au Sahel de juin à septembre durant la période dite de mousson. Cette période coïncide également avec le maximum annuel de la couverture nuageuse. Au travers du déploiement de la station mobile ARM (Atmospheric Radiation Measurement) durant une année en 2006 à Niamey (Niger), Bouniol et al. (2012) ont documenté les différents types de nuages observés pendant la mousson et ont montré la présence récurrente de nuages vers 6 km d'altitude dont l’impact radiatif est important dans les domaines du visible et de l'infrarouge. Dans le prolongement de cette étude, l'objectif de cette thèse est donc d'analyser plus en détails ces nuages de mi-niveau en documentant leur occurrence, leur cycle diurne et leurs caractéristiques macro- et microphysiques. Nous analysons également l'environnement thermodynamique dans lequel ces nuages sont observés ainsi que leurs effets radiatifs. D’autre part, en analysant les simulations effectuées dans le cadre du projet CMIP5, Roehrig et al. (2013) ont montré une sous-estimation de ce type de nuages dans les modèles de climat. Nous documentons plus précisément ici comment les modèles de climat et les modèles à aire limitée simulent ces nuages de mi-niveau. Afin de documenter ces nuages, des observations obtenues à partir d'instruments de télédétection active déployés sur deux sites sols : Niamey au Sahel et Bordj Badji Mokhtar au Sahara ont été combinées avec les données satellites de CloudSat et CALIPSO. Ces observations ont révélé une occurrence de ces nuages tout au long de l'année avec une prédominance durant la période de mousson. Ces nuages sont majoritairement observés dans le Sud et l'Ouest de l'Afrique de l'Ouest mais s’étendent jusqu’au cœur du Sahara. Leur présence dans cette zone désertique pourrait s’expliquer par la dynamique de la dépression thermique saharienne (Saharan Heat Low). Ces nuages sont généralement fins (la plupart ont une épaisseur inférieure à 1000 m) et sont principalement composés d'eau liquide. Une méthode de clustering appliquée à ces données nous a permis d'identifier trois types de nuages : le premier avec des bases plus basses, le deuxième avec des bases plus hautes et le dernier avec de plus fortes épaisseurs. Les radiosondages et les mesures de rayonnement nous ont permis de déterminer la stratification thermodynamique dans laquelle ces nuages sont observés ainsi que d’estimer leur impact radiatif. On observe généralement des inversions de température potentielle au sommet des nuages des deux premières familles. Dans les modèles de climat, nous avons mis en évidence une forte dispersion des occurrences des nuages de mi-niveau en termes de fréquence, de position et d’extension sur la verticale et de cycle saisonnier. L'analyse des simulations régionales indique aussi une influence de la résolution spatiale et de la paramétrisation de la convection sur la modélisation des nuages de mi-niveau simulés au Sahel et sur le Sahara. / Clouds have an important impact on the water and energy fluxes within the atmosphere. They also represent one of the main sources of uncertainties of climate models projections as a consequence of the difficulty to parametrize their associated processes as well as their interactions with their environment. In this thesis mid-level clouds are studied. Such clouds have been much less studied than low clouds and high clouds and the focus is on the West Africa. West Africa is characterized by a strong seasonality in precipitation that occur in the Sahel from June to September named the monsoon season. This period also coincides with the annual maximum of the cloud cover. Taking advantage of the one-year ARM Mobile Facility (AMF) deployment in 2006 in Niamey (Niger), Bouniol et al. (2012) documented the distinct cloud types observed during the monsoon and showed a frequent occurrence of clouds around 6 km height with an important radiative impact in the surface short-wave and long-wave domains. In the continuity of this study, the aim of this thesis is therefore to analyse in more details these mid-level clouds by documenting their occurrence, their diurnal cycle as well as their macro- and microphysical characteristics. We also analyse the thermodynamical environment in which these clouds are observed and their radiative effects. In a process-oriented evaluation of CMIP5 climate models, Roehrig et al. (2013) showed an underestimation of mid-level clouds. We document more precisely here how climate models and limited-area models simulate these mid-level clouds. To document those clouds, we combine observational data from active remote sensing instruments deployed at the two groundbased sites : Niamey in the Sahel and Bordj Badji Mokhtar in the Sahara, with merged CloudSatCALIPSO satellite. These observations reveal an occurrence of those clouds throughout the year with a predominance around the monsoon season. These clouds are preferentially observed in the Southern and Western part of West Africa but extend to the heart of the Sahara. Their presence in this desert zone may be explained by the dynamics of the Saharan Heat Low. Those clouds are usually quite thin (most of them are less than 1000 m deep) and mainly composed of liquid water. A clustering method applied to this data allows us to identify three different types of clouds : one with lower bases, one with higher bases and another with larger thicknesses. Radiosondes and radiation measurements allowed us to determine the thermodynamical stratification in which these clouds are observed as well as to estimate their radiative impact. Potential temperature inversions are generally observed at the top of the clouds of the first two families. In the climate models, we showed a strong dispersion of the occurrences of mid-level clouds in terms of frequency, location and vertical extension and seasonal cycle. Analysis of regional simulations also indicates an influence of spatial resolution and of the convection parametrization on the model ability in simulating mid-level clouds in the Sahel and in the Sahara.
303

Manoeuvre warfare in the South African campaign in German South West Africa during the First World War

Garcia, Antonio 02 1900 (has links)
This dissertation studies the First World War South African campaign in German South West Africa from 1914 until 1915. The campaign was characterised by the high mobility of the Union’s mounted soldiers which enabled swift advances and rapid envelopments. The German forces applied a defensive strategy relying on the lack of water and remoteness of the terrain to deter and prolong the Union’s invasion. The German force also relied on internal lines of communication to concentrate its forces on the Union’s advancing columns. The Union Defence Forces’s numbered approximately 50 000 compared to the German force of about 7 000. The campaign culminated on 9 July 1915 with the surrender of almost the entire German fighting force intact. This study analyses whether the victory can be attributed to the Union Defence Forces’s numerical superiority or the operational strategy and tactics which were applied during the campaign. It is argued that this operational strategy is congruent with the modern theory of manoeuvre warfare and that the campaign is therefore a textbook example of manoeuvre warfare theory / History / M.A. (History)
304

La vidéo comme outil de transfert de connaissances en santé publique au Burkina Faso : comparaison de trois genres narratifs

Hébert, Catherine 12 1900 (has links)
En Afrique, un continent où le paludisme est prévalent, la fièvre constitue le premier motif de consultation médicale. Des études sur l'utilisation des tests de diagnostic rapide du paludisme au Burkina Faso ont toutefois révélé qu'une proportion croissante de maladies fébriles aiguës ne sont pas liées au paludisme (Bottger et al., 2017). Dans certains cas, il pourrait s’agir de la dengue, puisqu’une épidémie de cette maladie a été déclarée au Burkina Faso en 2013, suivie d’une nouvelle flambée en 2016. Or, la formation des agents de santé burkinabè quant au traitement de la dengue est déficiente (Munoz, Ridde, Yaro, et Bottger, 2015). Cela représente un problème de santé publique quand on sait que la détection précoce et l’accès à des soins médicaux adaptés permettent de ramener les taux de mortalité en dessous de 1 %. La vidéo pourrait contribuer à pallier ce manque de formation puisqu’elle constitue un outil de transfert de connaissances efficace (Armstrong, Idriss, et Kim, 2011; Fiorella et Mayer, 2018; Yeung, Justice, et Pasic, 2009). Son utilisation a toutefois été peu étudiée en fonction de son genre narratif. La présente étude vise donc à évaluer l'efficacité relative de trois vidéos qui empruntent autant de genres narratifs distincts (1-reportage, 2-théâtre, 3- animation) pour améliorer les connaissances des prestataires de soins de santé burkinabè. Elle a aussi pour objectif d’identifier les éléments narratifs qui bonifient la vidéo comme outil de transfert de connaissances. Les vidéos ont été testées auprès d’étudiants en soins infirmiers à Ouagadougou (n = 482) à l’aide d’un test de connaissances. Trois groupes de discussion ont été formés avec des étudiants (N = 46) et des entretiens individuels ont été menés avec des professionnels de la santé (n = 10). / In Africa, a continent where malaria is prevalent, fever is the main reason for medical consultation. Studies on the use of malaria rapid diagnostic tests in Burkina Faso have shown, however, that an increasing proportion of acute febrile diseases are not related to malaria (Bottger et al., 2017). Some of these cases could be dengue fever, as an epidemic of this disease was declared in Burkina Faso in 2013, followed by a new outbreak in 2016. However, Burkinabe health workers have not received adequate training to treat dengue fever (Munoz et al., 2015). This is a public health problem, since it is known that early detection and access to appropriate medical care can reduce mortality rates to below 1%. Video could help fill this training gap, as it is an effective knowledge transfer tool (Armstrong, Idriss, & Kim, 2011; Fiorella & Mayer, 2018; Yeung, Justice, & Pasic, 2009). However, its use has been little studied in relation to narrative genre. The present study therefore aimed to evaluate the relative effectiveness of three videos adopting different narrative genres (1-journalism, 2- drama, 3-graphic animation) in improving the knowledge of Burkinabe healthcare providers. It also aimed to determine what narrative elements enhance video as a knowledge transfer tool. The videos were tested with nursing students (n = 482) in Ouagadougou using a knowledge questionnaire. Three focus groups were held with students (n = 46), and individual interviews were conducted with health professionals (n = 10).
305

Impact of Climate and Soil Variability on Crop Water Productivity and Food Security of Irrigated Agriculture in Northern Togo (West Africa)

Gadedjisso-Tossou, Agossou 12 March 2020 (has links)
West Africa is subject to frequent yield losses due to erratic rainfall and degraded soils. At the same time, its population is expected to double by 2050. This situation is alarming in northern Togo, a West African dry savannah area, where rainfed maize is a staple food. Thus, it is necessary to improve agricultural productivity, e.g., by evaluating and introducing alternative irrigation management strategies, which may be implemented in this region. For this purpose, the present investigation focused on evaluating the potential of deficit and supplemental irrigation, as well as assessing the impact of climate and soil variability on maize yield under irrigated agriculture using irrigation optimisation strategies in northern Togo. The Optimal Climate Change Adaption Strategies in Irrigation (OCCASION) framework was adapted and employed to address the research objectives. It involves: (i) a weather generator for simulating long-term climate time series; (ii) the AquaCrop model, which was utilised to simulate the irrigation during the growing periods and the maize yield response to given irrigation management strategies; and (iii) a problem-specific algorithm for optimal irrigation scheduling with limited water supply. Five irrigation management strategies viz. T1: no irrigation (NI), T2: controlled deficit irrigation (CDI) and T3: full irrigation (FI) in the wet season, T4: controlled deficit irrigation (CDI) and T5: full irrigation (FI) in the dry season were assessed regarding their impact on maize yield in northern Togo. The results showed high variability in rainfall during the wet season, which led to substantial variability in the expected yield for NI. This variability was significantly lessened when optimised supplemental irrigation management strategies (CDI or FI) were applied. This also holds for the irrigation scenarios under the dry season. Finally, these findings were validated by an irrigation field experiment conducted at an agricultural research institute in northern Togo. Under a moderate level of deficit irrigation during the vegetative and reproductive growth stages, the above-ground biomass and the maize grain yield were reduced. However, a moderate level of deficit irrigation during the vegetative growth stage could result in similar values of water productivity to that of fully irrigated treatment. It was found that, based on the values of the statistical indicators, AquaCrop has accurately simulated the maize grain yield for all the irrigation strategies evaluated. The results of this study revealed that climate variability might engender a higher variability in the maize yields of northern Togo than soil variability does. Large- and smallscale water harvesting, access to groundwater, and irrigation infrastructures would be required for implementing the irrigation management strategies assessed in this study.:Declaration iii Declaration of Conformity v Dedication vii Acknowledgements ix Abstract xi Table of Contents xv List of Figures xvii List of Tables xix List of Acronyms and Abbreviations xxi 1. Introduction 1 1.1 Background and Problem Statement 1 1.1.1 Global Fresh and Agricultural Water Use 1 1.1.2 Erratic Rainfall, Rising Temperatures, and Soil fertility depletion in West Africa 2 1.1.3 Transboundary Water Issues in West Africa 3 1.1.4 Agriculture and Water Use in Togo 3 1.2 Objectives of the Study 4 2. State of the Art 6 2.1 Relevant Agroecosystems, Farming Systems and Irrigation Management in West Africa 6 2.2 Key Performance Indicators: Water productivity and Food Security 8 2.3 Common Approaches Used to Evaluate Crop Water Productivity 9 2.4 Key production Factors: Climate, Soil and Management 9 2.5 Crop Yield Modelling 12 2.6 Integrated Modelling 13 3. Novel Framework for Optimising Irrigation Systems in West Africa 15 3.1 Model-based Sensitivity Analysis of Climate and Management Impact on Crop Water Productivity, Water Demand and Food Security 15 3.2 Experimental Validation of the Farm Model and Management Strategies, Soil Data Analysis and Modelling 17 3.3 Joint Stochastic Analysis of the Impact of Climate and Soil Variability on Crop Water Productivity and Food Security 19 4. Overview of Publications 21 4.1 Potential of Deficit and Supplemental Irrigation under Climate Variability in Northern Togo, West Africa 21 4.2 Impact of Irrigation Strategies on Maize (Zea mays L.) Production in the Savannah Region of Northern Togo (West Africa) 22 4.3 Impact of climate and soil variability on maize (Zea mays L.) yield under full and deficit irrigation in the savannah region of northern Togo, West Africa 23 5. Conclusion and Outlook 26 References 28 A. Selected Publications of the Author 37 A.1 Potential of Deficit and Supplemental Irrigation under Climate Variability in Northern Togo, West Africa 39 A.2 Impact of Irrigation Strategies on Maize (Zea mays L.) Production in the Savannah Region of Northern Togo (West Africa) 61 A.3 Impact of Climate and Soil Variability on Maize (Zea mays L.) Yield under Full and Deficit Irrigation in the Savannah Region of Northern Togo, West Africa 81 B. Histograms of distributions of the expected maize yield in northern Togo (scenarios in the third paper) 121
306

Land Privatization, Tenure Security, and Food Security in Rural Burkina Faso

Gardiner, Elizabeth N. January 2020 (has links)
No description available.
307

Entre terre et ville : migrations internes, réseaux sociaux et fécondité idéationnelle en région rurale sénégalaise

Boujija, Yacine 04 1900 (has links)
La migration interne est la principale forme de migration humaine et est sensible aux changements environnementaux, économiques et politiques. En Afrique de l'Ouest, les pressions environnementales et démographiques entraînent une précarité croissante pour les populations rurales dépendantes de l'agriculture pluviale, qui optent pour la migration temporaire vers les zones urbaines pour diversifier leurs moyens de subsistance. Ceci soulève deux questions : d’une part, il est important d’identifier les facteurs facilitant la migration et donc, la capacité d’adaptation des ménages vulnérables. Par ailleurs, dans les pays en pleine transition démographique, les écarts dans les niveaux de fécondité entre régions rurales et urbaines sont généralement élevés et les migrations entre ces milieux peuvent contribuer à la diffusion et l’homogénéisation de la fécondité. Ceci soulève la seconde question de comprendre si et comment la migration interne, surtout temporaire, s’associe à des changements dans les croyances et préférences de fécondité et de contraception chez les migrants. Malgré la pertinence de ces questions, nous constatons que la migration interne demeure le ‘parent pauvre’ en démographie et dans l’étude plus large des migrations; une position qui ne reflète pas son importance. Ainsi, pour contribuer à nos connaissances sur la migration interne dans le contexte de pays à faible et moyen revenu, cette thèse propose trois articles abordant les deux problématiques précédemment étalées. Pour y répondre, nous accordons une attention particulière au concept de réseaux sociaux; un concept central dans l’étude de la prise de décision de migrer et de la diffusion de la fécondité, mais qui fut mal intégré à l’étude de la migration interne et virtuellement absent du champ d’étude s’intéressant à la fécondité des populations migrantes. Nous utilisons un jumelage inédit de données, croisant les données longitudinales de l’observatoire de population de Niakhar, au Sénégal, à celles du projet Réseaux Sociaux et Santé à Niakhar. Conjointement, ces données permettent une analyse approfondie des trajectoires des migrants, leurs réseaux sociaux, ainsi que leur croyances et préférences de fécondité. Nos études se focalisent sur un seul village situé dans la zone d’étude de l’observatoire de population de Niakhar et s’intéressent aux migrants se dirigeant vers la capitale, Dakar. Dans le premier article, nous profitons des outils descriptifs et multivariés de l’analyse de survie afin d’explorer l’association entre l'exposition à du capital social migratoire dans les réseaux et la probabilité d’une première migration vers Dakar. Nous avons décomposé les réseaux de migrants selon les liens à des migrants de retour, des migrants actuels et des résidents non-migrants de la destination afin de capturer l'hétérogénéité du capital social lié à la migration. Nous testons également l'influence de la force des liens, évaluée subjectivement, et des liens structurellement faibles mesurés par les connexions de second ordre ("ami d'un ami"). Nous arrivons ainsi à revisiter certains des principaux postulats des théories de la causalité cumulative, du capital social (en migration) et de la force des liens. Par exemple, alors que les réseaux sont considérés être moins importants pour la migration interne, surtout dans des contextes où elle est généralisée, cette étude permet de revoir de tels constats en adoptant une définition élargie et plus complète du capital social migratoire, incluant des catégories de liens généralement sous-représentées ou absente dans la littérature empirique : les liens avec des non-migrants au lieu de destination et les liens faibles. Dans le second article, nous avons examiné comment la migration rurale-urbaine s’associe à des différences durables dans les croyances et les préférences en matière de fécondité et de contraception. À l’aide de quelques innovations méthodologiques et conceptuelles, nous avons distingué les effets d’adaptation et de sélection sur la fécondité des migrants temporaires à Dakar à l’aide de modèles de régression, malgré une approche transversale. Ceci fut notamment accompli grâce à l’inclusion d’un groupe de contrôle composé de futurs migrants et l’utilisation comme variables dépendantes de mesures idéationnelles de la fécondité, celle-ci étant moindrement affectées par les facteurs perturbants le calendrier génésique. Nous nous sommes également attardé aux migrants de retour, afin d’évaluer si l’adaptation persiste, une fois que les migrants réintègrent leur communauté d’origine. Enfin, nous avons ajouté une mesure des réseaux sociaux en ville, afin de tester son effet sur l’adaptation. Dans le dernier article, nous adoptons une approche ‘translocale’, mesurant les réseaux sociaux aux lieux de destination et d’origine, pour explorer à l’aide de modèles de régression, leur association avec la fécondité idéationnelle des migrants actuels à Dakar. L’analyse accorde une attention particulière aux liens maintenus avec la communauté du lieu d’origine, leur composition et leur structure, afin d’explorer la socialisation, ou l’influence des valeurs et normes acquises avant la migration, une hypothèse souvent peu approfondie dans l’étude de la fécondité des migrants. Plutôt que de concevoir la socialisation comme l’hypothèse nulle, nous l’identifions comme un phénomène continuant après la migration et s’opérant simultanément à l’adaptation. Dans l’ensemble, nos résultats confirment l’importance du rôle des réseaux sociaux comme déterminants de la migration interne, même dans des contextes où elle est généralisée. La migration semble aussi se placer comme un important vecteur de diffusion de la fécondité, par son influence sur les croyances et préférences des migrants actuels et de retour. Cette association est toutefois modérée par les relations maintenues au lieu d’origine. Plus largement nos résultats soulèvent quelques (re)questionnements théoriques et insistent sur l’importance d’adopter une approche centrée sur les réseaux sociaux multilocalisés dans l’étude de la migration interne. Enfin, nos résultats ont des implications substantielles sur le rôle potentiel des migrations rurales-urbaines dans les transformations sociodémographiques des pays du Sud et mettent en évidence les contradictions qui existent entre certaines politiques visant à limiter les migrations rurales-urbaines et celles voulant réduire la fécondité. / Internal migration is the main form of human migration and is sensitive to environmental, economic, and political changes. In West Africa, environmental stresses and rapid population growth are pressuring rural populations dependent on rain-fed agriculture into diversifying their livelihood strategies; this diversification largely depends on migration to urban areas. This raises two questions: firstly, it is important to identify the factors that facilitate migration and therefore the adaptation of vulnerable households. Secondly, in countries undergoing demographic transition, the gaps in fertility rates between rural and urban areas are generally high, and migrations between these regions can contribute to the diffusion and homogenization of fertility. This raises the second question of whether and how internal migration, especially temporary migration, is associated with changes in fertility and contraceptive beliefs and preferences among migrants. Despite the relevance of these questions, we find that internal migration remains the “stepchild” in demography and in the broader study of migration; a position that does not reflect its importance. Thus, to contribute to our understanding of internal migration in the context of low- and middle-income countries, this thesis proposes three papers addressing the two issues previously discussed. To answer them, we focus on the concept of social networks; a central concept in the study of the determinants of migration and the diffusion of fertility, but which was poorly integrated into the study of internal migration and virtually absent from the study of migrant fertility. We combine longitudinal data from the Niakhar Health and Demographic Surveillance System (NHDSS), in Senegal, with data from the Niakhar Social Networks and Health Project (NSNHP). Together, these data allow for an in-depth analysis of migrant trajectories, their social networks, as well as their fertility and contraceptive beliefs and preferences. Our studies focus on a single village located in the NHDSS study area and exclusively examine migrants to the capital, Dakar. In the first paper, we use descriptive and multivariate tools from survival analysis to explore the association between exposure to migratory social capital in networks and the probability of a first migration to Dakar. Taking advantage of our rich data, we disaggregated migrant networks into ties to returning migrants, current migrants, and non-migrant residents of the destination to capture the heterogeneity of social capital related to migration. We also tested the influence of the strength of ties, subjectively measured, and structurally weak ties measured by second-order connections ("friend of a friend"). We thus revisit some of the main hypotheses of the theories of cumulative causation, social capital (in migration), and strength of ties. For example, while networks are considered to be of lesser importance for internal migration, especially in contexts where it is widespread, this study allows us to reconsider such findings by adopting a broader and more comprehensive definition of migrant social capital, including categories of ties that are generally underrepresented or absent in empirical literature, such as ties to non-migrants at the destination and weak ties. In the second paper, we examined how rural-urban migration is associated with lasting differences in fertility and contraceptive beliefs and preferences. Using methodological and conceptual innovations, we distinguished the effects of adaptation and selection on the fertility of temporary migrants in Dakar through linear regression models, despite using a cross-sectional approach. This was achieved by including a control group consisting of future migrants and using ideational measures of fertility as dependent variables, which are less influenced by factors affecting the fertility calendar. We also focused on returning migrants to evaluate whether adaptation persists after migrants reintegrate into their community of origin. Additionally, we included a measure of urban social networks to test its effect on adaptation. In the last paper, we adopt a 'translocal' approach by measuring networks at both destination and origin to explore the association between social networks and the fertility ideation of current migrants in Dakar. The analysis pays particular attention to ties maintained with the community of origin and their composition and structure to explore socialization, or the influence of values and norms acquired before migration, an often-underexplored hypothesis in the study of migrant fertility. Rather than conceiving of socialization as the null hypothesis, we identify it as a phenomenon that continues after migration and operates simultaneously and interactively with adaptation. Our results confirm the importance of the role of social networks as a determinant of internal migration, even in contexts where it is widespread. Internal migration also appears to be an important vector for the diffusion of fertility, through its influence on the beliefs and preferences of current and returned migrants. However, this association is moderated by the relationships maintained at the place of origin. More broadly, our results raise some theoretical questions and emphasize the importance of adopting a multilocal social networks approach in the study of internal migration. Finally, our results have substantial implications for the potential role of rural-urban migration in sociodemographic transformations in the LMICs, highlighting the contradictions between public policies aiming to limit rural-urban migration and those aiming to reduce fertility.
308

Britain and the development of leftist ideology and organisations in West Africa: the Nigerian experience, 1945-1965

Tijani, Hakeem Ibikunle 08 1900 (has links)
Although organised Marxist organisations did not emerge in Nigeria until the mid-1940s, leftist ideology had been prevalent among nationalist and labour leaders since the late 1920s. Both official documents and oral histories indicate deep-rooted support for leftism in Nigeria and anxiety among British colonial officials that this support threatened the Colonial Office's own timetable for gradual decolonisation. This study analyses the development of leftist ideology and attempts to establish a nationwide leftist organisation in colonial and post-independent Nigeria. The role of the Zikist movement is retold in light of new evidence, while other leftist organisations are salvaged from the footnotes of Nigeria nationalist history. More importantly, the adaptability of Marxist-Leninist ideology to colonial reality by the different leftist groups in Nigeria is emphasized. The reaction of Anglo-American officials in Lagos and the metropolis towards the Communist Party of Great Britain and other leftist organisations' sponsorship of Marxist groups in Nigeria are discussed. Lastly, the continuity between the departing colonial power and the Balewa administration is addressed to juxtapose the linkage between the two governments. The study thus provides a lucid explanation for the failure of leftist ideology and organisations in Nigeria during the twentieth century. In this eight-chapter thesis I consistently argue, based on official documents from England, Nigeria, and the United States, that the role of Marxists and Soviet Cold War interests in colonial territories are relevant to nationalism and decolonisation in Nigeria; that the issue is not to determine or measure whether or not Anglo-American policies are direct response to Soviet interests; that there are political, economic, and diplomatic policies carried out as part of the transfer of power process; and that the success of these is partly a result of collaboration with local subaltern leaders and official resolve to institutionalise imperial preferences before independence on October 1, 1960. / History / D.Litt. et Phil. (History)
309

Advance fee fraud

Tanfa, Denis Yomi 31 March 2006 (has links)
The focus of this thesis is on Advance Fee Fraud (419 scams) on how it is executed and more importantly, on how it can be prevented. The research addresses the origins of AFF, the nature and extent of this crime and how the perpetrators are able to defraud their victims. The research described, examined and analysed the crimes, the perpetrators, the victims, adjudication and the prevention strategies of this fraud. Information was gathered through literature and empirical research. A qualitative research method was used to gather information from AFF offenders who were incarcerated in South African prisons in 2005. The results of the empirical research were carefully examined, analyzed and integrated into the various chapters of this thesis. A theoretical framework was also developed in an attempt to explain this complex phenomenon. The findings and recommendations in terms of the crimes, the criminals, the victims, adjudication and prevention were also made and some suggestions for further research thereof were also cited. / Criminology / D. Litt. et Phil. (Criminology)
310

Economic community of West African states (ECOWAS) : combining sub-regional economic integration with conflict resolution

Tive, Charles 08 May 2014 (has links)
The study utilizes regional integration theories like neo-functionalism, intergovernmentalism and new regionalism to analyse the formation, structure and transformation of the Economic Community of West African States (ECOWAS). It examines the role of ECOWAS as a sub-regional economic body and its transformation to a political and security body dealing with sub-regional conflict resolution. Though neo-functionalism is generally analysed in reference to European regional integration, the study attempts to draw some lessons from this theory. Also, new regionalism theory is utilized to examine the transformation of ECOWAS from a mere economic body to a security and political entity. Regionalism in West Africa was initially geared towards mere economic cooperation; however, the emergence of ECOWAS on the scene and its subsequent transformation witnessed several changes towards the path of security cooperation. Despite its involvement with the gigantic political and security related activities, a general evaluation of economic integration in West Africa depicts a low level of progress. The poor state of sub-regional economic integration shows that ECOWAS did not complete its regional economic integration agenda before diverting to other sectors of integration. ECOWAS peacekeeping operations have been the dominant topic in sub-regional conflict resolution in West Africa. However, other forms of conflict resolution, including mediation, negotiation, conciliation and arbitration have been severally utilized. Also, in some of the cases, peacekeeping operations have been deployed only after other peaceful efforts have failed. ECOWAS peacekeeping operations are divergent operations with different forms and mandates. Therefore, they are better analysed under the framework of peacekeeping, peace-enforcement and peace-making theories. ECOWAS peacekeeping operations have been a subject of debate by proponents of the principle of non-interference and those of the responsibility to protect. The expediency of military intervention for humanitarian reasons as well as the prevention of genocide, war crimes and catastrophic loss of lives has questioned the principle of non-interference and validated the principle of responsibility to protect. / Political Sciences / D. Litt. et Phil. (International Politics)

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