904 resultados para Equatorial Africa


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Durante a recente crise da dívida soberana europeia, os fundos soberanos demonstraram seu peso na esfera financeira global. Contribuíram para salvar o sistema financeiro dos países desenvolvidos, distribuindo créditos que as entidades financeiras tradicionais do Norte não podiam mais providenciar. Em 2012, os ativos totais desses fundos atingiram USD 4.620 bilhões, comparado aos USD 3.355 bilhões de antes da crise, no final de 2007 (Preqin, 2012). Sendo quase todos criados por economias em desenvolvimento ou subdesenvolvidas, os fundos soberanos podem então ser vistos como o símbolo de um recente reequilíbrio do poder a favor desses países (Santiso, 2008). Além disso, em um futuro próximo, espera-se que os fundos soberanos afastem-se dos países desenvolvidos para investir mais em países em desenvolvimento. Nesse contexto, os países africanos estão cada vez mais alvos de investimentos dos fundos (Triki & Faye, 2011). O estudo subjacente analisa dois fundos, o IFC ALAC e o Mubadala Development Company, para entender como, de acordo com as percepções dos seus gestores, os fundos soberanos podem ajudar no desenvolvimento dos países beneficiários. Mais precisamente, trata-se definir, através de um estudo de casos múltiplos, quais são os mecanismos pelos quais os fundos soberanos podem impactar o desenvolvimento da África ocidental. Os resultados sugerem que, segundo os gestores, os fundos soberanos podem desempenhar um papel significativo no desenvolvimento dos países beneficiários. Eles investem em alguns setores-chave da economia (bancos, infraestruturas etc.), criando condições favoráveis ao desenvolvimento local. Além disso, através de um efeito multiplicador, os investimentos dos fundos soberanos alavancam novos investimentos do setor privado local ou global, fortalecendo o tecido industrial e produtivo do país beneficiário. Porém, parece que as empresas beneficiárias não ajudam nas transferências de conhecimento e de tecnologia, embora sejam essenciais para o desenvolvimento econômico, e se limitam a programas de treinamento específico e de RSE. Além disso, apesar dos investimentos de fundos soberanos impulsionarem o crescimento da região, eles também podem agravar a dependência dessas economias à exportação de commodities. Finalmente, os impactos positivos dos fundos soberanos sobre a economia regional são muitas vezes reduzidos devido a conflitos políticos e barreiras estruturais exigindo reformas profundas e de longo prazo.

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This report was inspired by a personal motivation to acquire more in depth knowledge about Brazil and Lusophone (Portuguese speaking) African nations and how they interact with each other in relation to their common colonial histories, cultures, and on matters of international relations, international development, and international trade. The countries selected for purpose and focus of this report are Brazil, Angola, and Mozambique; reference will also be made with respect to other Lusophone African countries such as Cabo Verde, Guinea-Bissau, and São Tomé e Príncipe. Some of the research methodologies used to gather information about Brazil, Angola, Mozambique, and other Lusophone African nations in relation to their respective histories, international relations, international trade relations, and roles in the global economy as emerging market nations.

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There are distinct ways in which mining companies in South Africa operate today that are different from the operations three decades ago. Companies have grown in proportion, and the extension of the businesses is directly proportional to the mining activities hence the ultimate prize of degradation and related challenges has to be faced. There is increasing need to understand the relationship between corporate social responsibility and company returns. Both the opponents and proponents of CSR argue their case through convincing arguments presented here concerning the subject as brought out in this discussion. The immediate stakeholders of any company are the consumers, and they form a critical component of the company’s operations. A study of the evolution of CSR Mining in South Africa strategies is critical; as brought out in the discussion of CSR strategies employed three decades ago with what is done today

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Diet composition of the blue marlin, Makaira nigricans, from the southwestern equatorial Atlantic Ocean was analyzed between October 2004 and November 2005. In the 226 stomachs of fish ranging between 100 and 311 cm lower jaw -fork length (LJFL), 44 items were identified, including 31 fishes and 13 cephalopods. Seventy stomachs were empty (23.6 %). M. nigricans fed preferentially on heavy and muscular scombrid fishes especially upon the skipjack tuna, Katsuwonus pelamis (Linnaeus, 1758), probably to sustain their high metabolism, and on a variety of other items composed mainly by epipelagic species of fish and cephalopods.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Thaumastocoris peregrinus is a recently introduced invertebrate pest of non-native Eucalyptus plantations in the Southern Hemisphere. It was first reported from South Africa in 2003 and in Argentina in 2005. Since then, populations have grown explosively and it has attained an almost ubiquitous distribution over several regions in South Africa on 26 Eucalyptus species. Here we address three key questions regarding this invasion, namely whether only one species has been introduced, whether there were single or multiple introductions into South Africa and South America and what the source of the introduction might have been. To answer these questions, bar-coding using mitochondrial DNA (COI) sequence diversity was used to characterise the populations of this insect from Australia, Argentina, Brazil, South Africa and Uruguay. Analyses revealed three cryptic species in Australia, of which only T. peregrinus is represented in South Africa and South America. Thaumastocoris peregrinus populations contained eight haplotypes, with a pairwise nucleotide distance of 0.2-0.9% from seventeen locations in Australia. Three of these haplotypes are shared with populations in South America and South Africa, but the latter regions do not share haplotypes. These data, together with the current distribution of the haplotypes and the known direction of original spread in these regions, suggest that at least three distinct introductions of the insect occurred in South Africa and South America before 2005. The two most common haplotypes in Sydney, one of which was also found in Brisbane, are shared with the non-native regions. Sydney populations of T. peregrinus, which have regularly reached outbreak levels in recent years, might thus have served as source of these three distinct introductions into other regions of the Southern Hemisphere.

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In the absence of the selective availability, which was turned off on May 1, 2000, the ionosphere can be the largest source of error in GPS positioning and navigation. Its effects on GPS observable cause a code delays and phase advances. The magnitude of this error is affected by the local time of the day, season, solar cycle, geographical location of the receiver and Earth's magnetic field. As it is well known, the ionosphere is the main drawback for high accuracy positioning, when using single frequency receivers, either for point positioning or relative positioning of medium and long baselines. The ionosphere effects were investigated in the determination of point positioning and relative positioning using single frequency data. A model represented by a Fourier series type was implemented and the parameters were estimated from data collected at the active stations of RBMC (Brazilian Network for Continuous Monitoring of GPS satellites). The data input were the pseudorange observables filtered by the carrier phase. Quality control was implemented in order to analyse the adjustment and to validate the significance of the estimated parameters. Experiments were carried out in the equatorial region, using data collected from dual frequency receivers. In order to validate the model, the estimated values were compared with ground truth. For point and relative positioning of baselines of approximately 100 km, the values of the discrepancies indicated an error reduction better than 80% and 50% respectively, compared to the processing without the ionospheric model. These results give an indication that more research has to be done in order to provide support to the L1 GPS users in the Equatorial region.

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This pilot study uses concentrations of metals in maternal and cord blood at delivery, in seven selected geographical areas of South Africa, to determine prenatal environmental exposure to toxic metals. Samples of maternal and cord whole blood were analysed for levels of cadmium, mercury, lead, manganese, cobalt, copper, zinc, arsenic and selenium. Levels of some measured metals differed by site, indicating different environmental pollution levels in the regions selected for the study. Mercury levels were elevated in two coastal populations studied (Atlantic and Indian Ocean sites) with mothers from the Atlantic site having the highest median concentration of 1.78 mu g/L ranging from 0.44 to 8.82 mu g/L, which was found to be highly significant (p < 0.001) when compared to other sites, except the Indian Ocean site. The highest concentration of cadmium was measured in maternal blood from the Atlantic site with a median value of 0.25 mu g/L (range 0.05-0.89 mu g/L), and statistical significance of p < 0.032, when compared to all other sites studied, and p < 0.001 and p < 0.004 when compared to rural and industrial sites respectively, confounding factor for elevated cadmium levels was found to be cigarette smoking. Levels of lead were highest in the urban site, with a median value of 32.9 mu g/L (range 16-81.5 mu g/L), and statistically significant when compared with other sites (p < 0.003). Levels of selenium were highest in the Atlantic site reaching statistical significance (p < 0.001). All analysed metals were detected in umbilical cord blood samples and differed between sites, with mercury being highest in the Atlantic site (p < 0.001), lead being highest in the urban site (p < 0.004) and selenium in the Atlantic site (p < 0.001). To the best of our knowledge this pilot investigation is the first study performed in South Africa that measured multiple metals in delivering mothers and umbilical cord blood samples. These results will inform the selection of the geographical sites requiring further investigation in the main study.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The solar events that occurred at the end of October 2003 gave rise to very strong geomagnetic disturbances that peaked twice with Dst values reaching -345 nT around 0000 UT on 30 October and -400 nT around 2300 UT, on the same day. Disturbances in several ionospheric parameters were observed over Brazil. This work will focus on the ionospheric response to the initial westward prompt penetration electric field and on the strong intensification of the equatorial ionization anomaly that occurred because of the electric field polarity reversal that followed in the early morning hours of 29 October. The F layer peak height over the equator first decreased under the strong prompt penetration westward electric field, which was followed by significant height increase under eastward electric field. We have used Sheffield University Plasmasphere Ionosphere Model (SUPIM) with an intensified westward disturbed electric field in the presunrise hours, presumably due to prompt penetration from the magnetosphere, in order to study the effect of such a field in the ionosphere. The simulation results showed that prompt penetration of magnetospheric electric fields of westward polarity to the nightside equatorial region seems to be the most probable cause of the initial F layer height decreases. The intensification of the equatorial ionization anomaly and the unusual enhancement on F layer peak density, which was not modeled by the SUPIM, are explained as caused by the strong eastward electric field that followed the initial phase in combination with a highly variable disturbed meridional/transequatorial wind system as inferred from the F2 layer peak height variations. The highly dynamic wind pattern, with a short-term response (2-4 hours), is compatible with the predictions of some previous theoretical model calculations reported in the literature.

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Experimental data on the precipitation chemistry in the semi-arid savanna of South Africa is presented in this paper. A total of 901 rainwater samples were collected with automatic wet-only samplers at a rural site, Louis Trichardt, and at an industrial site, Amersfoort, from July 1986 to June 1999. The chemical composition of precipitation was analysed for seven inorganic and two organic ions, using ion chromatography. The most abundant ion was SO(4)(2-) and a large proportion of the precipitation is acidic, with 98% of samples at Amersfoort and 94% at Louis Trichardt having a pH below 5.6 ( average pH of 4.4 and 4.9, respectively). This acidity results from a mixture of mineral and organic acids, with mineral acids being the primary contributors to the precipitation acidity in Amersfoort, while at Louis Trichardt, organic and mineral acids contribute equal amounts of acidity. It was found that the composition of rainwater is controlled by five sources: marine, terrigenous, nitrogenous, biomass burning and anthropogenic sources. The relative contributions of these sources at the two sites were calculated. Anthropogenic sources dominate at Amersfoort and biomass burning at Louis Trichardt. Most ions exhibit a seasonal pattern at Louis Trichardt, with the highest concentrations occurring during the austral spring as a result of agricultural activities and biomass combustion, while at Amersfoort it is less pronounced due to the dominance of relatively constant industrial emissions. The results are compared to observations from other African regions.

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The chemical composition, as well as the sources contributing to rainwater chemistry have been determined at Skukuza, in the Kruger National Park, South Africa. Major inorganic and organic ions were determined in 93 rainwater samples collected using an automated wet-only sampler from July 1999 to June 2002. The results indicate that the rain is acidic and the averaged precipitation pH was 4.72. This acidity results from a mixture of mineral acids (82%, of which 50% is H2SO4) and organic acids (18%). Most of the H2SO4 component can be attributed to the emissions of sulphur dioxide from the industrial region on the Highveld. The wet deposition of S and N is 5.9 kgS.ha(-1).yr(-1) and 2.8 kgN.ha(-1).yr(-1), respectively. The N deposition was mainly in the form of NH4+. Terrigenous, sea salt component, nitrogenous and anthropogenic pollutants have been identified as potential sources of chemical components in rainwater. The results are compared to observations from other African regions.