Generation of a train of ultrashort pulses using periodic waves in tapered photonic crystal fibres

Funding This work was supported by the Ministry of Education , Nigeria for financial support through the TETFUND scholarship 55 scheme; CSIR [grant number 03(1264)/12/EMR-II].

Integração de alunos imigrantes e refugiados no Instituto Federal de Brasília - IFB

Dissertação apresentada para obtenção a grau de mestre na área de Educação Social e Intervenção Comunitária

Mapping of C4 plant input from North West Africa into North East Atlantic sediments

Mapping the abundance of 13C in leaf-wax components in surface sediments recovered from the seafloor off northwest Africa (0-35°N) reveals a clear pattern of delta13C distribution, indicating systematic changes in the proportions of terrestrial C3 and C4 plant input. At 20°N latitude, we find that isotopically enriched products characteristic of C4 plants account for more than 50% of the terrigenous inputs. This signal extends westward beneath the path of the dust-laden Sahara Air Layer (SAL). High C4 contributions, apparently carried by January trade winds, also extend far into the Gulf of Guinea. Similar distributions are obtained if summed pollen counts for the Chenopodiaceae-Amaranthaceae and the Poaceae are used as an independent C4 proxy. We conclude that the specificity of the latitudinal distribution of vegetation in North West Africa and the pathways of the wind systems (trade winds and SAL) are responsible for the observed isotopic patterns observed in the surface sediments. Molecular-isotopic maps on the marine-sedimentary time horizons (e.g., during the last glacial maximum) are thus a robust tool for assessing the phytogeographic changes on the tropical and sub-tropical continents, which have important implications for the changes in climatic and atmospheric conditions.

Estimate of the (R)USLE rainfall erosivity factor from monthly precipitation data in mainland Spain

The need for continuous recording rain gauges makes it difficult to determine the rainfall erosivity factor (R-factor) of the (R)USLE model in areas without good temporal data coverage. In mainland Spain, the Nature Conservation Institute (ICONA) determined the R-factor at few selected pluviographs, so simple estimates of the R-factor are definitely of great interest. The objectives of this study were: (1) to identify a readily available estimate of the R-factor for mainland Spain; (2) to discuss the applicability of a single (global) estimate based on analysis of regional results; (3) to evaluate the effect of record length on estimate precision and accuracy; and (4) to validate an available regression model developed by ICONA. Four estimators based on monthly precipitation were computed at 74 rainfall stations throughout mainland Spain. The regression analysis conducted at a global level clearly showed that modified Fournier index (MFI) ranked first among all assessed indexes. Applicability of this preliminary global model across mainland Spain was evaluated by analyzing regression results obtained at a regional level. It was found that three contiguous regions of eastern Spain (Catalonia, Valencian Community and Murcia) could have a different rainfall erosivity pattern, so a new regression analysis was conducted by dividing mainland Spain into two areas: Eastern Spain and plateau-lowland area. A comparative analysis concluded that the bi-areal regression model based on MFI for a 10-year record length provided a simple, precise and accurate estimate of the R-factor in mainland Spain. Finally, validation of the regression model proposed by ICONA showed that R-ICONA index overpredicted the R-factor by approximately 19%.

Las potencias subregionales en el sistema internacional de posguerra fría: ¿nuevos actores en la política internacional?

En trabajos anteriores, hemos avanzado en la identificación y diferenciación de tres categorías de potencias: potencias mundiales, potencias medias y potencias regionales. Pero, más allá de las potencias mundiales y las potencias medias que se encuentran en el centro del sistema-mundial, y las potencias regionales que se ubican en la semiperiferia, ¿es posible hablar de potencias que se encuentren en la periferia? Como se trata de Estados periféricos, ¿pueden ser calificados como “potencias”? ¿En qué radicaría su relevancia y envergadura? Dichas “potencias” ¿pueden ser agrupadas en una nueva categoría? De ser así ¿qué características compartirían? El objetivo de este documento es proponer una nueva  categoría de potencias en el sistema internacional: las potencias subregionales.

Crisis Económica en África Occidental: el caso de Dakar, 1929-1939

En este artículo se explora el impacto socio-económico de la crisis internacional de 1929 en Senegal y más concretamente en la ciudad-puerto de Dakar. Se analizan las consecuencias de la dependencia externa y la extroversión económica que caracterizaba a las estructuras productivas coloniales, destacando también la respuesta organizada de los movimientos sociales africanos. Por otra parte, se estudia la evolución de las infraestructuras y actividad portuaria, observando la metropolización regional de Dakar durante este periodo.

Linguas en contacto na escrita electrónica galega

La escritura electrónica es en la actualidad una modalidad gráfica de gran éxito que en los últimos años comenzó a ser albo de diversas investigaciones lingüísticas. Sin embargo, un análisis exclusivamente gramatical, desvinculado del medio social en el que se utiliza, parece insuficiente para entender un fenómeno de tal complejidad. Consecuentemente, analizamos sus características en base a los condicionamientos sociolingüísticos presentes en el caso gallego. Así, examinamos las implicaciones de la situación de contacto y conflicto lingüístico entre el gallego y el español, señalamos las motivaciones de la alternancia de código y de las interferencias lingüísticas –que no siempre coinciden con las que operan en la lengua común- y observamos que estas prácticas son consecuencia de la confluencia de factores sociolingüísticos con otros de naturaleza pragmática.

A roadmap to Sierra Leone English: a sociohistorical and ecological perstective

Programa de doctorado: Traducción, comunicación y cultura

Economic Development and Mass Poverty in Africa: Assessment of the Nigerian Experience

The forces surrounding the emerging economies of underdeveloped world, especially Africa has practically stifled its economic progress, growth, development and sustainability. This economic condition brings to the fore the massive onslaught of rural/urban poverty which the African continent grapples with since the post-world war II era to date. The economic misfortunes and incidence of mass poverty in Africa, vis-à-vis Nigeria is used as a point of departure in this study. The paper underscores the ideological and philosophical undertone of international capital manifesting in form of colonialism and imperialism as a major character in the historical process of underdevelopment and mass poverty in peripheral states of Africa, Asia and Latin America, respectively. Of particular interest in this study is the activities of domestic bourgeoisie elite class who have vigorously displayed some degree of lack of much needed vision and abject lack of desires to draw up workable plans to redeem the battered image of African/ Nigerian economic misfortunes. This state of affairs has practically engendered economic underdevelopment, misery and disturbing levels of poverty in the nation-state system. The paper concludes with the forward towards realizing the vision 20-20-20 objectives in the 21t century and beyond.

Minority Question in the Nigerian Governmental Process

Given the monumental friction, tension and acrimony occasioned by minority question in Nigeria’s governmental process, the paper is aimed at encapsulating the dynamics of minority question as it affects/impact the governmental process of Nigeria. It argues that minority question in Nigeria, just like other parts of the developed world, including Australia for example, reinforces itself in the culture and pervasive nature of ethnicity, defined in terms of group interest, sectional polarization, self-esteem and identification. Findings revealed that, Ethnicity is therefore considered as the epicenter of minority agitations as each of these groups struggle not in the nation’s interest, but in the interest of identifiable groups and regional hegemony for recognition and control oil resources. The paper concludes that the minority question cannot be divorce from governmental processes, because it has become a part of socio-political fabric of the Nigerian state, hence, the need for a virile federal structure that recognizes and responds positively to the interest of the minor groups is essential. The paper is a survey of literatures from existing works of scholars, generated to enhance the understanding of the subject matter under review; as such the methodology is strictly based on content secondary data.

Measuring the geographic distribution of maternal education in Africa

Thesis (Master's)--University of Washington, 2016-08

Financialisation, Capital Accumulation and Economic Development : A Theoretical and Empirical Investigation of the Nigerian Economy

The primary focus of this study is to highlight those unobtrusive, yet fundamental, factors undermining economic development in Nigeria. To begin with, it posits that the decelerating pace of capital accumulation in Nigeria, which naturally occasions rising unemployment and poverty levels, and widening inequality gap, is the result of the ‘low possibility’ of capitalist enterprises in the country of earning an adequate rate of profit from their productive processes. In turn, the ‘low possibility’ is argued to be the result of the uneven development inherent in the modern capitalist structure, the high cost of capital and of production peculiar to Nigeria, and the ineffective demand for goods made in Nigeria: these elements are viewed as been precipitated by the contradictions of the contemporary political-economic arrangement that organises the Social Structures of Accumulation. For Nigeria to ‘develop’, it is contended that the unobtrusive elements inherent in the contradiction of the political-economic economic that undermine the capitalists’ ability to earn a commensurate rate of profit in the country needs to be fully addressed first. Furthermore, this study suggests that it is crucial the country embraces knowledge-based industrialisation if it is to achieve some form of ‘competitive advantage’ in the global market, which could enable its productive processes extract a commensurate level of profit from the market. To facilitate the knowledge-based industrialisation, the state should, not only create a conducive environment for industrial development but also play the lead role in transforming the peripheral and oil dependent economy to a knowledge-based economy by coordinating business organisations and investing in high-risk innovations.

Symptoms of Poststroke Depression among Stroke Survivors: An Appraisal of Psychiatry Needs and Care during Physiotherapy Rehabilitation

Purpose. To identify stroke survivors with symptoms of poststroke depression and the extent of psychiatry needs and care they have received while on physiotherapy rehabilitation. Participants. Fifty stroke survivors (22 females and 28 males) at the outpatient unit of Physiotherapy Department, University of Nigeria Teaching Hospital, Enugu, who gave their informed consent, were randomly selected. Their age range and mean age were 26–66 years and 54.76 ± 8.79 years, respectively. Method. A multiple case study of 50 stroke survivors for symptoms of poststroke depression was done with Beck’s Depression Inventory, mini mental status examination tool, and Modified Motor Assessment Scale. The tests were performed independently by the participants except otherwise stated and scored on a scale of 0–6. Data were analyzed using -test for proportional significance and chi-square test for determining relationship between variables, at p < 0.05. Results. Twenty-one (42.0%) stroke survivors had symptoms of PSD, which was significantly dependent on duration of stroke ( = 21.680, df = 6, and p = 0.001), yet none of the participants had a psychiatry review. Conclusions. Symptoms of PSD may be common in cold compared to new cases of stroke and may need psychiatry care while on physiotherapy rehabilitation.