Dissertations / Theses on the topic 'Gambier Basin'

The Otway Basin of southeast Australia is the subject of this thesis, which incorporates pre-existing geological, hydraulic and major element hydrogeological data with new isotope hydrogeochemical investigations. The region is an Upper Cretaceous–Tertiary basin, filled with siliciclastic and calcareous aquifers and aquitards and characterised by late volcanic activity, pervasive faulting and karstification. (For complete abstract open document.)

In the 1980s, USAID (US Agency for International Development) funded an environmental assessment of dams on the Gambia River, which determined that construction of the Balingho anti-salinity barrage would result in adverse unmitigative environmental and social consequences. Attempts by host country politicians, USAID and UNDP (United Nations Development Programme) to discredit this process made it necessary to take the matter to the Natural Resource Defense Council. A case study of the events surrounding these dams and their potential construction illustrates the ‘big dam’ paradigm and its potential harm to people, their livelihoods and the environment in Sub-Saharan Africa.

It is argued in this thesis that the climate signal shows more strongly in the runoff regime of the Gambia River Basin (GRB) than the signal from deforestation. Partial and multiple regression was used to partition the effects on runoff of rainfall characteristics and deforestation over the GRB since the turn of this century. The expected shorter, higher more rapidly responding wet season flood peaks which result from deforestation have not occurred in the GRB. Rather, peak floods have fluctuated since the beginning of the century, but showing a clear declining trend similar to the rainfall regime. The large size (z 7550 km') of the sub-catchments of the GRB inhibit synchronisation of the rapid runoff that is associated with deforestation. Furthermore, deforestation, as it occurs in the GRB, takes place piece-meal as small plots of land are cleared. The nature of clearance of vegetation is important; the vegetation cleared is either replaced with another type of vegetation, for example, groundnuts or millet, or is soon allowed to recover after a cropping phase. Surface and sub-surface hydrological processes within the GRB are therefore not subjected to the severe form of alteration that characterise massive and total clearance of vegetation schemes in urban development. However, deforestation has significantly affected low flowsthere are now longer periods of lower dry season flows, and these are ascribed to the diminishing recharge of ground water. By augmenting overland flow and reducing interception and infiltration, deforestation causes a reduction in ground water recharge, which is an important component of dry season flows. Both climate change and deforestation have worked in parallel to cause a fluctuating but declining flow regime of the Gambia River. This, in turn, affects both the agricultural potential and productivity of the GRB.

Outdoor education is believed to be a new teaching approach and method in the education framework which relates to learning through natural places using direct experience. However, the teaching approach that is mostly used in the Gambian schools is based on the traditional approach of teachings as well as many African countries. As a relatively new teaching technique, outdoor education is gaining recognition from many researchers who are developing a keen interest in it. Thus, the aim of the current thesis is to investigate the perceptions of Gambian Basic and Secondary school teachers about outdoor education. in that regard, six (6) Gambian teachers from different teaching subjects, grades, and regions reported their views about outdoor education. A qualitative approach methodology with the use of semi-structured interview was employed to get teachers perceptions. After the data collection, thematic analysis was used for analyzing the collected data from which three (3) themes emerged to report the participants’ opinions. The participants revealed their basic knowledge and perceptions about outdoor education and presented some characteristics and examples of how the practice outdoor education. They emphasized that they view outdoor education as a teaching approach with the use of outdoors. However, according to them, any teaching activity that involves using the outside the four corners of the classroom or the school premises, is considered outdoor education. They noted that outdoor education can take place in the form of excursions, fieldtrips, classes outside the class under a tree or within the school premises. Besides, although the teachers indicated that the main teaching approach, they use is still the traditional teaching and learning approach, they showed willingness to enrich their classes with use of outdoor education. They further revealed that the main places they conduct outdoor education is the school yard, under a tree, a visit to places of interest, excursions to various historical places or museums and the like. The Gambian teachers acknowledged many potentials of outdoor education to the students including stimulation of multi-senses, increased understanding, improved social relation and cooperation, boosting of their health and wellbeing, developing curiosity, and giving students a sense of freedom and happiness. However, participants also revealed several barriers that suppress them from doing outdoor education effectively. Among the barriers mentioned includes, inadequate funding, lack of support from parents and school administrators, lack of pedagogical training, tight schedule, and limited time. Thus, further research is needed to help testifying the results of the current study and give more insight into the field of outdoor education in the Gambia and Africa at large

This thesis presents the results of an investigation of the structure and evolution of the Senegal continental margin and the adjacent Gambia Basin, based on seismic, gravity, magnetic, bathymetric and borehole data. It establishes the relation between the structure of this region and the overall geological and tectonic history of the Eastern Atlantic Ocean. The study begins with a presentation of the general geological features of the area and a review of previous work close to the West African continental margin. New bathymetric information from the area between 2°-18°N and 7°-45°W is then presented, which provides a detailed picture of the seafloor relief, its structural grain and an indication of the depositional patterns. Long single-channel seismic reflection profiles running from the continental shelf through the Gambia Basin have been tied to deep-sea drill sites to establish a seismic stratigraphy. The extent of the main reflectors and the structural characteristics of inactive ocean fracture zones have been determined from approximately 3500 km of reflection profiles. Analysis of the basement depth reveals the presence of large depth anomalies in the region, which have been related to the uplift of the nearby Cape Verde Rise. The position of an important tectonic boundary between rough and smooth basement in the study area has been defined as lying between magnetic anomalies M21 and M16 (150-142 Ma). Seismic refraction lines shot in the Gambia Basin and in the region immediately to the south reveal an anomalous oceanic structure, associated with the formation of fracture zones under the sediments of the basin. Crust as thin as 1.4 km, without an oceanic Layer 3 has been found near 1l°N, 23°30'W. In view of the presence of several closely-spaced fracture zones, the crustal structure of much of the Gambia Basin is probably not of normal oceanic type. Possible mechanisms responsible for the anomalous accretion of ocean crust are discussed. Crustal structure has also been inferred from new free-air gravity anomaly measurements between 3°-1.8°N and 7°-26°W and from the Bouguer anomalies on land. Two-dimensional crustal models based on gravity anomalies and constrained by refraction and other data have been derived for several traverses across the West African continental margin and the Gambia Basin. These models demonstrate important differences in crustal thickness and lateral variations in the density of the crustal and mantle rocks across the area. The models indicate that neither the transitional crust under the Senegal Basin and the adjacent shelf and slope, nor the fracture zones under the Gambia Basin are isostatically compensated at the level of the Noho. Furthermore, a large part of the Senegal continental margin and the Senegal Basin is shown to be underlain by transitional, stretched continental crust on which a thick sedimentary cover has accumulated. The subsidence history and the structural models indicate that the Cenozoic sediments are not isostatically balanced by the mechanism of local Airy compensation. These studies reveal that the structure of the Senegal margin and the Gambia Basin exhibits important differences from that of adjacent areas to the north and south, contrasts which appear to be related to the early opening history of the equatorial Atlantic.

Le moustique anophèle est le vecteur majeur du paludisme. Cette maladie provoquée par les parasites du genre Plasmodium est transmise par une piqûre infectieuse d'anophèle. Le parasite subit des pertes massives pendant son cycle de développement chez l'anophèle, ce qui suggère que les moustiques sont capables de développer une réaction immunitaire efficace contre le parasite. Cependant, les mécanismes cellulaires et moléculaires des interactions entre parasite et anophèle restent mal connus. Pour aborder cette étude, nous avons commencé par établir un système in vitro basée sur la culture d'une lignée cellulaire d'anophèles de type hémocytaire, en présence d'oocinètes de Plasmodium. Nous avons démontré que, dans ce système in vitro, les parasites induisent une réponse immunitaire de type non spécifique comprenant, entre autres, la synthèse de peptides antimicrobiens et la phagocytose. La protéine à motif thioester, TEP1, agit en tant qu'opsonine chez l'anophèle et favorise la phagocytose des bactéries par les hémocytes. Après avoir vérifié que notre lignée cellulaire était capable de produire une protéine TEPI fonctionnelle pour la phagocytose, nous avons utilisé ce système pour étudier la fonction de TEP1 dans la réponse antiparasitaire. Contrairement à la situation observée in vivo, nous n'avons cependant pas détecté de liaison directe entre TEP1 et la surface des oocinètes et conclu que le modèle in vitro était peu adapté à l'analyse fonctionnelle de TEP1. Nous avons alors développé la technique d'invalidation des gènes par l'ARN double brin (dsRNA) chez l'anophèle adulte et avons pu démontrer que la liaison de TEP1 sur la surface des parasites induit leur élimination dans le tube digestif du moustique. Ces résultats montrent le rôle crucial des réactions immunitaires de l'anophèle vis-à-vis du parasite. Nous avons utilisé la microscopie électronique à transmission pour suivre le développement du parasite P. Berghei chez A. Gambiae et avons observé que la majorité des oocinètes envahit les cellules épithéliales du moustique avant la polymérisation complète de la matrice péritrophique. De plus, ces oocinètes prennent préférentiellement un itinéraire extracellulaire pour migrer à travers le tube digestif. Cette observation est très importante, car elle démontre que les parasites sont confrontés à l'environnement hostile de l'espace extracellulaire du tube digestif plutôt qu'au milieu cytoplasmique des cellules épithéliales. Enfin, nous avons démontré que la dite “zone filamenteuse” qui entoure les parasites mélanisés se compose d'actine polymérisée. Nous l'avons renommée "zone d'actine". La formation de cette zone se produit lorsque les parasites sont morts ou mourants, ce qui suggère qu'elle n'est pas directement responsable de la mort des parasites. L'invalidation de TEP1 par la technique du dsRNA supprime la formation de la zone d'actine, ce qui montre l'implication, directe ou indirecte, de TEP1 dans cette structure. Nous proposons ainsi un modèle d'élimination parasitaire: le parasite est d'abord tué par un mécanisme dépendant de TEP1, puis, subit une lyse ou mélanisation. Les cellules épithéliales identifient les parasites morts ou mourants et se protègent par polymérisation d'actine dans la zone de contact
Anopheles mosquitoes are important vectors of human malaria, which is caused by Plasmodium parasites in the sub-Sahara. The transmission of this disease is initiated by an infectious bite of an Anopheles mosquito. The parasite undergoes massive losses during its development in the mosquito, suggesting that mosquitoes are able to mount a potent immune response against the parasite. However, the cellular and molecular mechanisms of mosquito-parasite interactions are not completely understood. We first established an in vitro co-culture system using a mosquito hemocyte-like cell line of A. Gambiae and chose a thioester-containing protein 1 (TEP1), which acts as an opsonin and promotes phagocytosis of bacteria by hemocytes, as a candidate to study its role in mosquito-parasite interactions. We demonstrated that the mosquito cells in the co-culture system responsed to the parasite presence by activation of general immune responses, including the induction of synthesis of antimicrobial peptides and phagocytosis. As no specific interactions between TEP1 and the ookinetes could be detected, we concluded that our in vitro model is unsuitable for TEP1 functional analysis. By using a double-stranded RNA (dsRNA) silencing technique and phenotype assays, we demonstrated that the binding of TEP1 to Plasmodium parasites mediates their killing in the mosquito midgut. These results document the important role of mosquito immune responses, especially those mediated by hemocytes, in the establishment of vectorial capacity in A. Gambiae. We performed transmission electron microscopy to follow the development of P. Berghei parasites in the A. Gambiae midgut. We observed that the majority of P. Berghei ookinetes invade the mosquito midgut before complete polymerization of the peritrophic matrix. Moreover, during the invasion, ookinetes preferentially take an extracellular route to migrate across the midgut. This conclusion is important as it suggests that during midgut invasion parasites are rather facing hostile environlment of the extracellular space than the cytoplasmic milieu of the epithelial cells. We demonstrated that the previously described filamentous zone surrounding melanized parasites is composed of polymerized actin and renamed it the “actin zone”. The formation of the actin zone occurs when parasites are dead or dying, suggesting that the actin zone is not associated directly with parasite killing. The silencing of TEP1 by dsRNA abolishes the formation of the actin zone in both susceptible and refractory mosquitoes, suggesting that TEP1 could be the genetic determinant of this structure. Therefore, a model of actin-based parasite clearance is proposed: the parasite is first killed by a TEP1-dependent mechanism, and subsequently the parasite is lysed or melanized. Dead or dying parasites are recognized by epithelial cells, and the actin zone is then formed to separate the dead or dying parasites from host tissues

Chemical control of mosquito vectors, via indoor residual spraying or insecticide treated bed nets, is an integral component of malaria control strategies. Limited availability of insecticides licensed for public health and the rapid development of resistance in mosquito populations to these insecticides, in particular to some pyrethroids, may compromise vector control efforts. With the exception of mutations in the insecticide target sites, relatively little is known about the genetics of pyrethroid resistance in malaria vectors. In some populations candidate effector genes, e.g. cyp6p3 or cyp6m2 in An. gambiae s.s. from Akron, Benin, have been identified as being over expressed in resistant strains but the underlying mechanisms responsible for the increased expression remain unknown. In this study, a combination of quantitative PCR, genetic mapping and microarray tools were used to investigate the mechanisms responsible for pyrethroid resistance in two African major malaria vectors, Anopheles gambiae and An. arabiensis. The current work was unable to confirm an association of these known candidates in either a laboratory colony established from Akron or in recent field caught material. Therefore a genetic mapping approach was adopted using field collected mated females to generate F2 isofemale lines. A major QTL on chromosome 3R was identified which coincides with a genomic region previously implicated in pyrethroid resistance in East African populations. This is the first genetic mapping of insecticide resistance using natural out-bred populations of Anopheles and the advantages and limitations of this approach are discussed. In a second experiment, genetic loci involved in permethrin resistance in An. arabiensis were mapped by establishing genetic crosses between a permethrin resistant strain from Chad and a susceptible strain from Mozambique. A single QTL on chromosome 2R was identified in the F2 progeny that accounts for ~24% of the phenotypic variance. This QTL coincides with a large cluster of detoxification genes. Pyrethroid resistance is not associated with target-site mutations in this population. Finally, microarrays were used to identify genes differentially expressed between a backcross population, generated by crossing the F1 population from the resistant Chad strain and the susceptible Mozambique strain of An. arabiensis back to the parental resistant strain, with the susceptible strain. A number of candidate genes were identified, including the P450 genes cyp4h24 and cyp9j5, but neither of these were located within the boundaries of the QTL on 2R. These findings support the presence of metabolic resistance in this population and fine mapping of the identified QTL as well as further investigation of the microarray hits is warranted.

This thesis aims at a critical understanding of how the curriculum policy making process is perceived by teachers and policy-makers in The Gambia, a former British colony. The complexity of curriculum policy issues requires this study to draw on multiple theoretical underpinnings in order to gain insight into curriculum policy relating to Basic Education in The Gambia. Therefore, curriculum theories and education policy literature including the issues of globalisation and national policy are engaged to frame the data collection, analysis and findings. Data obtained from semi structured interviews are used to analyse the perceptions. The thesis examines critically the historical and contemporary approaches to curriculum policy making, identifies the key policy players and analyses their significance in the construction of the national curriculum policy. The thesis further investigates experiences and views about the policy in practice and recommends a new approach to the curriculum policy making. Two levels of the curriculum policy making process are found to be influential in The Gambia: the international (global) and the national and local levels. While the global influences are profound on the strategic education policy, the national and local effects are stronger than the global impact on the operational policy (curriculum plans). The thesis argues that policy is not simply received and implemented as given. Although incidences of compliance are noted, curriculum policy guidelines developed by the Ministry of Education are continually interpreted, sometimes misunderstood and/or resisted by the teachers. Gaps between policy and the implementation are found, resulting from the resource constraints and the practitioners’ influences and impacts. A curriculum policy reform is recommended, recognising the centrality of teachers in the curriculum process, promoting the empowerment of the teachers and building their capacity to engage in informed policy mediation and to enable them to put their own policy into practice.

This item is only available electronically.
A detailed foraminiferal profile of the Late Eocene-Early Oligocene boundary in the Gambier Limestone was investigated by local and regional biostratigraphic correlations together with foraminiferal biofacies analysis. Occurrences of important planktonic species were used to produce chronostratigraphic charts to interpret the duration of the unconformable Eocene/Oligocene boundary. Deposition of the Early Oligocene basal Gambier Limestone is coeval with the Aldinga Transgression and is characteristic of an isochronous flooding event at sequence boundary Pr4/Ru1. The Late Eocene Narrawaturk Marl, where present, correlates to the Tuit regional biofacies member, and the Late/Middle Eocene sand unit is coeval to the Tortachilla unit. Hiatuses are represented by erosional surfaces at sequence boundaries. The maximum estimated duration of the hiatus ranges from Pr1 to Pr4/Ru1 indicating an age gap of approximately 3 Ma, with the majority of samples showing a hiatus between Pr3 to Pr4/Ru4, representing a time slice of approximately 2 Ma. The unconformable Eocene/Oligocene contact therefore parallels the Chinaman Gully downcut in the St Vincent Basin, indicating a regional event coeval with and in response to the oceanic-oxygen isotopic glaciation.
Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Physical Sciences, 2000

Maps in pocket inside back cover.
Includes published papers and abstracts of works by the author
"November 2003"
Includes bibliographical references.
Various paging : ill. (chiefly col.), maps, plates, charts (some folded) ; 30 cm. + 2 scaled seismic survey maps
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, National Centre for Petroleum Geology and Geophysics and Discipline of Geology and Geophysics, 2004

Maps in pocket inside back cover.
Includes published papers and abstracts of works by the author
"November 2003"
Includes bibliographical references.
Various paging : ill. (chiefly col.), maps, plates, charts (some folded) ; 30 cm. + 2 scaled seismic survey maps
Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, National Centre for Petroleum Geology and Geophysics and Discipline of Geology and Geophysics, 2004

碩士
長庚大學
商管專業學院
107
Performance management is a concept in the field of human resource management and is defined as a “continuous process of identifying, measuring and developing the performance of individuals and aligning performance with the strategic goals of the organization”. Performance management system was carried out by the Human Resources Unit of Gambia Police Force several years ago; starting first with Senior Managers and trickling down to all employees at all levels within the two portfolios of The Gambia Police Force, namely, strategic and operational staff. The performance management system developed for this purpose consisted of key performance areas, strategic sets, goals and targets including the developmental needs of employees in order to improve their skills and self-development. However, there were indications that there has not been a clear strategy on the use of the results of the performance management system by the Force for decision-making purposes, such as on promotion, reward or consequences for non-achievement of targets. Moreover, there were indications of a lack of participation among employees and a lack of feedback on the results of the final performance assessment, even though mid-term feedback was provided directly for those at the supervisory level. A significant amount of time is spent every year by the Human Resources Unit of the Force on this process, however, its impacts remain questionable. For the purpose of this research, a study was conducted with the objective of evaluating the impacts of the performance management system on employee performance in The Gambia Police Force and the research questions were as follows: (1) How was the planning of performance management conducted in The Gambia Police Force? (2) What steps were followed for on- going feedback and employee input? (3) How effective was the evaluation and review of the performance management process? (4) How effective was the overall implementation of the performance management system? In order to do justice to the above research questions, a structured questionnaire, together with a number of open-ended questions were used to collect data from the employees of the Force. A purposive sampling method was used to identify study participants from both the strategic and operational staff. The study participants were sent an email with a link to a questionnaire and feedbacks from them thus received. The qualitative data was analysed using data, a text flow analysis method. The qualitative analysis of the responses shows that a significant number of participants agreed with most of the issues raised. However, the high number of respondents who indicated their disagreement (at different levels) or neutrality with regards to the issues points to the fact that there is much to be done in order to improve the impacts of performance management system in The Gambia Police Force. Regarding the implementation stage of performance management, the majority of respondents (68%) were either in disagreement or unsure about this. The qualitative analysis uncovered interesting views on all aspects of performance management system, including lack of involvement in target setting and implementation of the system and different expectations on performance outcomes. Insufficient training and lack of support on the system was found to be one of the key areas which might have resulted in a lack of trust in the system and created a condition of imbalance in relation to the whole system. The findings from this study are in line with the general notion that positive performance management systems should be highly anchored by practices and organizational contexts with certain traits. Indeed, as reported in this research, the Force needs to provide more performance management training, engage employees and lay critical emphasis on employee recognition. In this way, the performance management system will be enhanced, deliver more value and meet the desired outcomes of the organization.

碩士
長庚大學
商管專業學院
107
Since merging the former Customs & Excise and Domestic Taxes Departments in 2004 for the purpose of maximising revenue collection and bringing economic independence and self-reliance as a country, the Gambia Revenue Authority has been performing exceptionally well and as a result, it now accounts for more than 70% of Government recurrent expenses. Though despite these improvements, there are challenges affecting revenue collection and they are; Inconvenience (overcrowded paying offices, with long queues and long waiting hours), people not knowing how much tax to pay, too busy to go and pay their taxes, people forgetting payment due dates, breakdown of communication between GRA and its customers (Taxpayers), none compliance, and fraud and corruption at collection centres. The main aim of this study is to explore the potential benefits of using information technology on tax collection in The Gambia. This study used a descriptive survey research design. Both primary and secondary data were used in this study. The primary data comprises of survey questionnaires, interview guides and the secondary data was obtained from annual reports of three Revenue Authorities (Rwanda, Tanzania and Kenya) that had successfully implemented i-TAX. Interviews were conducted on five GRA staff (one auditor, an IT officer and three cashiers). The data collected was purely qualitative in nature. The study revealed that despite a high rate of percentage of registered businesses there are still few businesses operating behind the scene, and besides, a huge number of businesses pay their taxes at the end of the year. This has resulted into inconvenience (overcrowding, and long queues at paying stations) and none compliance with the manual filing system. In addition, the study discovered many business owners were willing to be notified of payment due dates. Furthermore, the study revealed disconnection between GRA and its customers (communication is GRA2C), overcrowding at paying stations, corruption (involving direct cash payments), poor record keeping, and the bad perception of the taxpayer about GRA are some of the issues affecting tax collection at GRA. The researcher was motivated by the results drawn from the study that indicates, GRA tax collection system(manual) is faced with some problems that are affecting tax collection. In conclusion, the use of Information Technology (i-TAX) such as; e-filling where taxpayers can file their tax returns online; e-payments to pay their taxes, will help enhance tax collection in the Gambia as recommended in the following ways; better Tax compliance and lower compliance cost, reduced administrative and collection costs, decreased need for personnel, time savings for taxpayers, transparency in assessment, collection, and related processes.

碩士
長庚大學
商管專業學院
107
The research intended to determine the relationship between talent management on organisation’s performance: A look at The Gambia Police Force. The study aimed mainly at examining the relationship between talent management, career management and organisation performance. Closed or structured questionnaires were administered to make sure that all the police officers respond to the same type of questions. It is the main the main instrument used in the data collection. The sample size for this research was made up of 122 police officer: 6 Commissioner, 14 Superintendents, 15 Assistant Superintendents 39 Inspectors and 48 other ranks. Three (3) Police Regions of The Gambia were targeted namely: Banjul, Kanifing and West Coast. Data was explored using SPSS 22. Correlation coefficient was used to test for the strength of the relationship between talent management (an independent variable) and organisational performance (a dependent or outcome variable) at The Gambia Police. The results were presented in tables, mean and charts. The research has proven that talent management had positive and significant influence on The Gambia Police Force performance. It is recommended that talent management practices should be enhanced. This will contribute to better organisational performance.