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The Nsuze Group (∼3000 Ma) in South Africa is comprised of volcanics and sediments that rest unconformably on older continental crust. Nsuze volcanics, which range in composition from basalt to rhyolite and include a significant proportion of andesites, have tholelitic to calc-alkaline geochemical affinities. Incompatible element distributions in Nsuze volcanics are similar to those in volcanics associated with continental-margin arcs and exhibit a typical subduction zone component (SZC)...
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Birthrates in tropical Africa are among the highest in the world, but many zones in the region have below-norm fertility. Proximate determinants are the framework used to explain the occurrence of these zones. Of greatest significance are factors that affect duration of postpartum amenorrhea, incidences of sterility and spontaneous intrauterine abortions, and frequency of intercourse. POPULATION is growing more rapidly in tropical Africa than in any other principal world region. The average...
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ABSTRACT Poor water supply is the dominant issue in African agriculture. A project aimed at reducing the impact of drought onfood supply levels in Africa is described. The result was a computer software package for analysis of monthly rainfall records which can be operated on a desktop computer. Referencing of current weather analysis results against historical expectations was a major part of the system design. Another feature was to combine current records with climate normals to project...
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Abstract This paper examines language of instruction policies in primary schools in Burundi where French is used for teaching in grades five and six and for administration of the concours national which selects students for admission to secondary schools. The present language policy, adopted in 1973, has been implemented in the context of dramatic increases in school enrolment achieved chiefly through the introduction of double shifts that have shortened the teaching schedule. Classroom...
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Since 1980 harsh economic factors have hit Malawi: periodic drought and subsequent decline in crop output, falling world prices for export commodities, and an ever heavier debt burden. How have these economic shocks touched children and schools? This article shows how Malawi's protracted period of adjustment temporarily towered school enrolment, as rural families drew on their children's labour to backstop erosion of subsistence and surplus production. But this slowing of school expansion...
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The prevalence of sickle cell trait (SCT), was studied in 263 students enrolled in a physical education college in Côte-d'Ivoire. Most of the students were athletes of average training level, but some competed at an international level. The prevalence of SCT (hemoglobin AS), observed in the student population (13.7%) was not significantly different from that of the general population (12%) of Côte-d'Ivoire and did not differ between sexes. The percentage of international level athletes was...