965 resultados para South-South relationship
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Nylandtia (Polygalaceae) is a small South African genus of two or more species distributed mainly in the Cape region. Previous studies based on anatomical, morphological and molecular data have already revealed a close relationship between Nylandtia and Muraltia, a genus of 117 species that is nearly endemic to South Africa. New evidence from molecular studies of family Polygalaceae and genus Muraltia shows that Nylandtia is derived from genus Muraltia, and is nested in Muraltia subgenus Psiloclada. These results have prompted a morphological re-evaluation of the genera Nylandtia and Muraltia, supporting the conclusion that the two species of Nylandtia currently recognized, N. spinosa and N. scoparia, should be included in subgenus Psiloclada within the genus Muraltia. Only one nomenclatural change is necessary: Muraltia spinosa (L.) E Forest & J. C. Manning, comb. nov.
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The influence of sedimentation, depth and substratum angle on sponge assemblages in the Wakatobi region, south-eastern Sulawesi, Indonesia was considered. Sponge assemblages were sampled from two reef localities. The first reef (Sampela) was highly impacted by high sedimentation rates with fine sediment particles that settle slowly, while the second (Hoga) experienced only fast settling coarse sediment with lower overall sedimentation rates. Sponge assemblages were sampled (area occupied and numbers) on the reef fiat (0 m) and at 5 (reef crest), 10 and 15 m (15 m at Hoga only). Some significant (P < 0.001) differences were observed in the area occupied and the number of sponge patches between surface angles and sites. Significantly lower (t > 4.61, df = 9, P < 0.001) sponge numbers, percentage cover and richness were associated with the reef flat at both sites compared with all other depths at each site, with the exception of abundance of sponges on the reef flat at Sampela, which was much greater than at any other depth sampled. Species richness increased with depth at both sites but differences between surface angles were only recorded at Sampela, with higher species richness being found on vertical, inclined and horizontal surfaces respectively A total of 100 sponge species (total area sampled 52.5 m(2)) was reported from the two sites, with 58 species found at Sampela and 71 species at Hoga (41% of species shared). Multi-dimensional scaling (MDS) indicated differences in assemblage structure between sites and most depth intervals, but not substratum angles. A number of biological (e.g. competition and predation) and physical (e.g. sedimentation and aerial exposure) factors were considered to control sponge abundance and richness. Unexpectedly a significant (F-1,F-169 = 148.98, P < 0.001) positive linear relationship was found between sponge density and area occupied. In areas of high sponge coverage, the number of patches was also high, possibly due to fragmentation of large sponges produced as a result of predation and physical disturbance. The MDS results were also the same whether sponge numbers or percentage cover estimates were used, suggesting that although these different approaches yield different sorts of information, the same assemblage structure can be identified.
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The quality of a country’s human-resource base can be said to determine its level of success in social and economic development. This study focuses on some␣of the major human-resource development issues that surround the implementation of South Africa’s policy of multilingualism in education. It begins by discussing the relationship between knowledge, language, and human-resource, social and economic development within the global cultural economy. It then considers the situation in South Africa and, in particular, the implications of that country’s colonial and neo-colonial past for attempts to implement the new policy. Drawing on the linguistic-diversity-in-education debate in the United Kingdom of the past three decades, it assesses the first phase of an in-service teacher-education programme that was carried out at the Project for Alternative Education in South Africa (PRAESA) based at the University of Cape Town. The authors identify key short- and long-term issues related to knowledge exchange in education in multilingual societies, especially concerning the use of African languages as mediums for teaching and learning.
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In the aftermath of the 1971 war, nearly 250,000 people found themselves stranded in various parts of the subcontinent. These 'trapped minorities' became hostages in a complex negotiation process that highlighted how questions of citizenship and belonging remained unresolved in post-Partition South Asia. By studying three groups - the non-Bengalis, the Bengalis and the prisoners of war in a comparative perspective, this paper re-visits the question of who was welcome within certain borders and on what terms. It argues that these decisions depended not just on the state's policies towards 'outsiders' but also upon its own relationship with its minority communities.
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The recession of mountain glaciers around the world has been linked to anthropogenic climate change and small glaciers (e.g. < 2 km2) are thought to be particularly vulnerable, with reports of their disappearance from several regions. However, the response of small glaciers to climate change can be modulated by non-climatic factors such as topography and debris cover and there remain a number of regions where their recent change has evaded scrutiny. This paper presents results of the first multi-year remote sensing survey of glaciers in the Kodar Mountains, the only glaciers in SE Siberia, which we compare to previous glacier inventories from this continental setting that reported total glacier areas of 18.8 km2 in ca. 1963 (12.6 km2 of exposed ice) and 15.5 km2 in 1974 (12 km2 of exposed ice). Mapping their debris-covered termini is difficult but delineation of debris-free ice on Landsat imagery reveals 34 glaciers with a total area of 11.72 ± 0.72 km2 in 1995, followed by a reduction to 9.53 ± 0.29 km2 in 2001 and 7.01 ± 0.23 km2 in 2010. This represents a ~ 44% decrease in exposed glacier ice between ca. 1963 and 2010, but with 40% lost since 1995 and with individual glaciers losing as much as 93% of their exposed ice. Thus, although continental glaciers are generally thought to be less sensitive than their maritime counterparts, a recent acceleration in shrinkage of exposed ice has taken place and we note its coincidence with a strong summer warming trend in the region initiated at the start of the 1980s. Whilst smaller and shorter glaciers have, proportionally, tended to shrink more rapidly, we find no statistically significant relationship between shrinkage and elevation characteristics, aspect or solar radiation. This is probably due to the small sample size, limited elevation range, and topographic setting of the glaciers in deep valleys-heads. Furthermore, many of the glaciers possess debris-covered termini and it is likely that the ablation of buried ice is lagging the shrinkage of exposed ice, such that a growth in the proportion of debris cover is occurring, as observed elsewhere. If recent trends continue, we hypothesise that glaciers could evolve into a type of rock glacier within the next few decades, introducing additional complexity in their response and delaying their potential demise.
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OBJECTIVE: To determine whether the peroxisome proliferator-activated receptor (PPAR)-gamma Pro12ala polymorphism modulates susceptibility to diabetes in South Asians. RESEARCH DESIGN AND METHODS: South Asians (n = 697) and Caucasians (n = 457) living in Dallas/Forth Worth, Texas, and South Asians living in Chennai, India (n = 1,619), were enrolled for this study. PPAR-gamma Pro12Ala was determined using restriction fragment-length polymorphism. Insulin responsiveness to an oral glucose tolerance test (OGTT) was measured in nondiabetic subjects. RESULTS: The Caucasian diabetic subjects had significantly lower prevalence of PPAR-gamma 12Ala when compared with the Caucasian nondiabetic subjects (20 vs. 9%, P = 0.006). However, there were no significant differences between diabetic and nondiabetic subjects with reference to the Pro12Ala polymorphism among the South Asians living in Dallas (20 vs. 23%) and in India (19 vs. 19.3%). Although Caucasians carrying PPAR-gamma Pro12Ala had lower plasma insulin levels at 2 h of OGTT than the wild-type (Pro/Pro) carriers (76 +/- 68 and 54 +/- 33 microU/ml, respectively, P = 0.01), no differences in either fasting or 2-h plasma insulin concentrations were found between South Asians carrying the PPAR-gamma Pro12Ala polymorphism and those with the wild-type genotype at either Chennai or Dallas. CONCLUSIONS: Although further replication studies are necessary to test the validity of the described genotype-phenotype relationship, our study supports the hypothesis that the PPAR-gamma Pro12Ala polymorphism is protective against diabetes in Caucasians but not in South Asians.
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Objectives. This paper considers the intersection of Corporate Social Responsibility (CSR) and social entrepreneurship in South Africa through the lens of institutional theories and draws upon a number of illustrative case study examples. In particular it: (1) charts the historically evolving relationship between CSR and social entrepreneurship in South Africa, and how this relationship has been informed by institutional changes since the end of apartheid, particularly over the last few years; (2) identifies different interactional relationship forms between social enterprises and corporates engaging in CSR, with an emphasis on new innovative multi-stakeholder partnerships; and (3) considers internal engagements with social responsibility by SME social enterprises in South Africa. Prior Work. Reflecting South Africa’s history of division, the controversial role of business during apartheid, and the ongoing legacies of that period, the South African government has been particularly pro-active in encouraging companies to contribute to development and societal transformation through CSR and Black Economic Empowerment (BEE). Accordingly a substantial body of work now exists examining and critically reflecting upon CSR and BEE across a range of sectors. In response to perceived problems with BEE, efforts have recently been made to foster broader-based economic empowerment. However the implications of these transitions for the relationship between CSR and social entrepreneurship in South Africa have received scant academic attention. Approach. Analysis is undertaken of legislative and policy changes in South Africa with a bearing on CSR and social entrepreneurship. Data collected during fieldwork in South Africa working with 6 social enterprise case studies is utilised including qualitative data from key informant interviews, focus groups with stakeholders and observational research. Results. The paper considers the historically evolving relationship between CSR and social entrepreneurship in South Africa informed by institutional change. Five different relationship forms are identified and illustrated with reference to case examples. Finally internal engagement with social responsibility concerns by small and medium social enterprises are critically discussed. Implications. This paper sheds light on some of the innovative partnerships emerging between corporates and social enterprises in South Africa. It reflects on some of the strengths and weaknesses of South Africa’s policy and legislative approaches. Value. The paper provides insights useful for academic and practitioner audiences. It also has policy relevance, in particularly for other African countries potentially looking to follow South Africa’s example, in the development of legislative and policy frameworks to promote corporate responsibility, empowerment and transformation.
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We extend the theory of the multinational enterprise (MNE) by exploring the concept of subsidiary-specific advantages (SSAs) as a driver for subsidiary performance. We investigate the relationship of host country-specific advantages (host CSAs) in the form of market attractiveness, SSAs and subsidiary sales as they affect subsidiary performance. From an original primary dataset of 101 British multinational (MNE) subsidiaries in six South East Asian countries, our analysis reveals three significant findings. First, host market attractiveness has a statistically positive impact on the performance of subsidiaries. Second, the three traditional SSAs of general management, marketing capabilities and invested capital enhance subsidiary performance. Third, we examine geographic direction and types of customers for subsidiary sales by following international accounting standards. We find that these subsidiaries generate on average 95 percent of total sales from the Asia Pacific region and 91 percent of total sales from external customers. Our findings have important research and managerial implications.
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In this paper we present the capability of a new network of field mill sensors to monitor the atmospheric electric field at various locations in South America; we also show some early results. The main objective of the new network is to obtain the characteristic Universal Time diurnal curve of the atmospheric electric field in fair weather, known as the Carnegie curve. The Carnegie curve is closely related to the current sources flowing in the Global Atmospheric Electric Circuit so that another goal is the study of this relationship on various time scales (transient/monthly/seasonal/annual). Also, by operating this new network, we may also study departures of the Carnegie curve from its long term average value related to various solar, geophysical and atmospheric phenomena such as the solar cycle, solar flares and energetic charged particles, galactic cosmic rays, seismic activity and specific meteorological events. We then expect to have a better understanding of the influence of these phenomena on the Global Atmospheric Electric Circuit and its time-varying behavior.
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In 1984 and 1985 a series of experiments was undertaken in which dayside ionospheric flows were measured by the EISCAT “Polar” experiment, while observations of the solar wind and interplanetary magnetic field (IMF) were made by the AMPTE UKS and IRM spacecraft upstream from the Earth's bow shock. As a result, 40 h of simultaneous data were acquired, which are analysed in this paper to investigate the relationship between the ionospheric flow and the North-South (Bz) component of the IMF. The ionospheric flow data have 2.5 min resolution, and cover the dayside local time sector from ∼ 09:30 to ∼ 18:30 M.L.T. and the latitude range from 70.8° to 74.3°. Using cross-correlation analysis it is shown that clear relationships do exist between the ionospheric flow and IMF Bz, but that the form of the relations depends strongly on latitude and local time. These dependencies are readily interpreted in terms of a twinvortex flow pattern in which the magnitude and latitudinal extent of the flows become successively larger as Bz becomes successively more negative. Detailed maps of the flow are derived for a range of Bz values (between ± 4 nT) which clearly demonstrate the presence of these effects in the data. The data also suggest that the morning reversal in the East-West component of flow moves to earlier local times as Bz, declines in value and becomes negative. The correlation analysis also provides information on the ionospheric response time to changes in IMF Bz, it being found that the response is very rapid indeed. The most rapid response occurs in the noon to mid-afternoon sector, where the westward flows of the dusk cell respond with a delay of 3.9 ± 2.2 min to changes in the North-South field at the subsolar magnetopause. The flows appear to evolve in form over the subsequent ~ 5 min interval, however, as indicated by the longer response times found for the northward component of flow in this sector (6.7 ±2.2 min), and in data from earlier and later local times. No evidence is found for a latitudinal gradient in response time; changes in flow take place coherently in time across the entire radar field-of-view.
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There is a tendency to reduce ventilation rates and natural or hybrid ventilation systems to ensure the conservation of energy in school buildings. However, high indoor pollutant concentration, due to natural or hybrid ventilation systems may have a significant adverse impact on the health and academic performance of pupils and students. Reviewed evidence shows that this can be detrimental to health and wellbeing in schools because of the learner density within a small area, eventually indicating that CO2 concentrations can rise to very high levels (about 4000 ppm) in classrooms during occupancy periods. In South Africa’s naturally ventilated classrooms, it is not clear whether the environmental conditions are conducive for learning. In addition, natural ventilation will be minimized given the fact that in cold, wet or windy weather, doors and windows will commonly remain closed. Evidence from literature based studies indicates that the significance of ventilation techniques is not understood satisfactorily and additional information concerning naturally ventilated schools has to be provided for better design and policy formulation. To develop a thorough understanding of the environments in classrooms, many other parameters have to be considered as well, such as outdoor air quality, CO2 concentrations, temperature and relative humidity and safety issues that may be important drawbacks for naturally ventilated schools. The aim of this paper is to develop a conceptual understanding of methods that can be implemented to assess the effectiveness of naturally ventilated classrooms in Gauteng, South Africa. A theoretical concept with an embedded practical methodology have been proposed for the research programme to investigate the relationship between ventilation rates and learning in schools in Gauteng , a province in South Africa. It is important that existing and future school buildings must include adequate outdoor ventilation, control of moisture, and avoidance of indoor exposures to microbiologic and chemical substances considered likely to have adverse effects in South Africa. Adequate ventilation in classrooms is necessary to reduce and/or eradicate the transmission of indoor pollutants.
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Background, aim and scope Soil organic matter (SOM) is known to increase with time as landscapes recover after a major disturbance; however, little is known about the evolution of the chemistry of SOM in reconstructed ecosystems. In this study, we assessed the development of SOM chemistry in a chronosequence (space for time substitution) of restored Jarrah forest sites in Western Australia. Materials and methods Replicated samples were taken at the surface of the mineral soil as well as deeper in the profile at sites of 1, 3, 6, 9, 12, and 17 years of age. A molecular approach was developed to distinguish and quantify numerous individual compounds in SOM. This used accelerated solvent extraction in conjunction with gas chromatography mass spectrometry. A novel multivariate statistical approach was used to assess changes in accelerated solvent extraction (ASE)-gas chromatography-mass spectrometry (GCMS) spectra. This enabled us to track SOM developmental trajectories with restoration time. Results Results showed total carbon concentrations approached that of native forests soils by 17 years of restoration. Using the relate protocol in PRIMER, we demonstrated an overall linear relationship with site age at both depths, indicating that changes in SOM chemistry were occurring. Conclusions The surface soils were seen to approach native molecular compositions while the deeper soil retained a more stable chemical signature, suggesting litter from the developing diverse plant community has altered SOM near the surface. Our new approach for assessing SOM development, combining ASE-GCMS with illuminating multivariate statistical analysis, holds great promise to more fully develop ASE for the characterisation of SOM.
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A Regional Climate Model (RegCM3) 10-year (1990-1999) simulation over southwestern South Atlantic Ocean (SAO) is evaluated to assess the mean climatology and the simulation errors of turbulent fluxes over the sea. Moreover, the relationship between these fluxes and the rainfall over some cyclogenetic areas is also analyzed. The RegCM3 results are validated using some reanalyses datasets (ERA40, R2, GPCP and WHOI). The summer and winter spatial patterns of latent and sensible heat fluxes simulated by the RegCM3 are in agreement with the reanalyses (WHOI, R2 and ERA40). They show large latent heat fluxes exchange in the subtropical SAO and at higher latitudes in the warm waters of Brazil Current. In particular, the magnitude of RegCM3 latent heat fluxes is similar to the WHOI, which is probably related to two factors: (a) small specific humidity bias, and (b) the RegCM3 flux algorithm. In contrast, the RegCM3 presents large overestimation of sensible heat flux, though it simulates well their spatial pattern. This simulation error is associated with the RegCM3 underestimation of the 2-m air temperature. In southwestern SAO, in three known cyclogenetic areas, the reanalyses and the RegCM3 show the existence of different physical mechanisms that control the annual cycles of latent/sensible heating and rainfall. It is shown that over the eastern coast of Uruguay (35A degrees-43A degrees S) and the southeastern coast of Argentina (44A degrees-52A degrees S) the sea-air moisture and heat exchange play an important role to control the annual cycle of precipitation. This does not happen on the south/southeastern coast of Brazil.
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Based on previous observational studies on cold extreme events over southern South America, some recent studies suggest a possible relationship between Rossby wave propagation remotely triggered and the occurrence of frost. Using the concept of linear theory of Rossby wave propagation, this paper analyzes the propagation of such waves in two different basic states that correspond to austral winters with maximum and minimum generalized frost frequency of occurrence in the Wet Pampa (central-northwest Argentina). In order to determine the wave trajectories, the ray tracing technique is used in this study. Some theoretical discussion about this technique is also presented. The analysis of the basic state, from a theoretical point of view and based on the calculation of ray tracings, corroborates that remotely excited Rossby waves is the mechanism that favors the maximum occurrence of generalized frosts. The basic state in which the waves propagate is what conditions the places where they are excited. The Rossby waves are excited in determined places of the atmosphere, propagating towards South America along the jet streams that act as wave guides, favoring the generation of generalized frosts. In summary, this paper presents an overview of the ray tracing technique and how it can be used to investigate an important synoptic event, such as frost in a specific region, and its relationship with the propagation of large scale planetary waves.
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The South American (SA) rainy season is studied in this paper through the application of a multivariate Empirical Orthogonal Function (EOF) analysis to a SA gridded precipitation analysis and to the components of Lorenz Energy Cycle (LEC) derived from the National Centers for Environmental Prediction (NCEP) reanalysis. The EOF analysis leads to the identification of patterns of the rainy season and the associated mechanisms in terms of their energetics. The first combined EOF represents the northwest-southeast dipole of the precipitation between South and Central America, the South American Monsoon System (SAMS). The second combined EOF represents a synoptic pattern associated with the SACZ (South Atlantic convergence zone) and the third EOF is in spatial quadrature to the second EOF. The phase relationship of the EOFs, as computed from the principal components (PCs), suggests a nonlinear transition from the SACZ to the fully developed SAMS mode by November and between both components describing the SACZ by September-October (the rainy season onset). According to the LEC, the first mode is dominated by the eddy generation term at its maximum, the second by both baroclinic and eddy generation terms and the third by barotropic instability previous to the connection to the second mode by September-October. The predominance of the different LEC components at each phase of the SAMS can be used as an indicator of the onset of the rainy season in terms of physical processes, while the existence of the outstanding spectral peaks in the time dependence of the EOFs at the intraseasonal time scale could be used for monitoring purposes. Copyright (C) 2009 Royal Meteorological Society