University of South Africa

About: University of South Africa is a education organization based out in Pretoria, South Africa. It is known for research contribution in the topics: Context (language use) & Population. The organization has 8478 authors who have published 19960 publications receiving 237688 citations. The organization is also known as: Unisa.

Enrolment into Birth to Ten (BTT): population and sample characteristics.

Abstract: Summary. The population under study in the South African longitudinal study of urban children and their families, ‘Birth to Ten’ (BTT), comprised all births during a 7-week period from April to June 1990 in Soweto-Johannesburg. Specification of the population base for the cohort was hampered by a number of flaws in the notification and recordkeeping systems of the local authorities. As far as could be ascertained, 5460 singleton births occurred during this time to women who gave a permanent address within the defined region. Enrolment into BTT took place over the first 15 months of the study and covered the antenatal, delivery, 6-month and 1-year periods. By the end of this time, and despite a major health service strike during the delivery phase, 74% of all births (4029 cases) had been enrolled into the study. There were marked variations in levels of enrolment, however, by population group membership, residential area and place of delivery. In general, there was substantial under-enrolment of largely middle-class white women and their babies. Initial non-enrolment of specific segments of the population and attrition of the enrolled sample up to the end of the first year are discussed in the context of racial and social differentiation in South Africa.

On the process of gaining language as a resource in mathematics education

Abstract: In this paper, we expand our prior work on mathematics education in contexts of language diversity by elaborating on the three perspectives on language described by Ruiz (NABE J 8(2):15–34, 1984): language-as-right, language-as-resource, and language-as-problem. We illustrate our arguments with data taken from research contexts in Catalonia-Spain and South Africa. In these two parts of the world, the language policy in education has long been an issue, with a monolingual orientation that values one language (i.e., Catalan in Catalonia and English in South Africa) over others. Throughout the introduction of specific examples of policy documents, classroom practices, and participants’ reports, our main point is that the right of using the students’ languages makes sense because it is itself more than an intrinsic human right; it is an option that potentially benefits the creation of mathematics learning opportunities. Especially for the instances of classroom practices, our examples can be considered as representative in that they point to a common situation in our data: despite the fact of the language of learning and teaching being fixed, there is room for the learners and the teacher to take or react to a decision on what language to use, with whom, and how in concrete moments of the interaction. However, on the basis of our studies and drawing on the literature in mathematics education and language diversity, we argue that language rights are not sufficiently connected to language as a pedagogical resource. The enactment of these rights is still contributing in many ways to the social and political construction of problems concerning the role of certain languages in classroom interaction. We conclude the paper by discussing some possibilities for framing language as a resource that provide effective support to all students’ learning of mathematics.

Bilingual Students using their Languages in the Learning of Mathematics

Abstract: This paper is about how immigrant bilingual students use their languages in the learning of mathematics. Our research has been with immigrant bilinguals in Catalonia, Spain, who arrived at a young age from SouthAmerican countries. We use a critical sociolinguistic approach, which draws on social theory in the analysis of how language is involved in the construction of teaching and learning opportunities. Our data point to the differences in the ways that the Spanish dominant bilingual students use their two languages during their engagement in mathematical activity. The shifts from Catalan to Spanish, and from Spanish to Catalan, coincide with shifts in the complexity of the students’ mathematical practices. The students tend to use the two languages for different purposes, depending on the complexity of the mathematical practices, and in relation to different social settings that coexist within the classroom. What does it mean to learn mathematics in a language that is not your first language in a country that is not your own? This is the situation in many immigrant bilingual mathematics classrooms in Catalonia, Spain. A majority of immigrant students in these classrooms have Spanish as a first language. However, they learn mathematics in Catalan, which is the official language for learning and teaching mathematics in Catalonia. How do these Spanish dominant bilingual students use languages during mathematics teaching and learning in Catalan classrooms? Do they switch languages during mathematical activity? If so, what are some of the factors that promote their language switching within the context of specific lessons? In this paper we explore those questions. We do this by drawing on a wider study involving immigrant bilingual children attending a Catalan school who were either born in Catalonia or went there at a young age from South-American countries such as Ecuador, Bolivia, Peru and Colombia. Our analysis highlighted two recurrent themes in regard to which language was used by the students: 1) the impact from acquiring specific vocabulary in the second language; and 2) the development of mathematical argumentations in the first language. We argue that the shifts from Catalan to Spanish coincided with shifts in the complexity of the students’ mathematical practices. The students tended to use the two languages for different

The South Africa Stress and Health Study: Rationale and Design

Abstract: The South Africa Stress and Health Study (SASH) is a large psychiatric epidemiological survey that is currently underway in South Africa. It is a part of the World Health Organization's World Mental Health (WMH) 2000 initiative and seeks to complete interviews with a nationally representative sample of 5000 adults. The WMH initiative is obtaining population-based data on the prevalence and severity of specific psychiatric disorders, demographic and psychosocial correlates of these diagnoses, and the levels and adequacy of mental health service utilization. SASH is using the fully structured pencil and paper version of the WHO Composite International Diagnostic Interview (CIDI) to assess lifetime and 12-month rates of mental disorders using both the DSM-IV and the ICD-10 diagnostic systems. In addition, the SASH seeks to collect information on the prevalence of exposure to physical and psychological torture in South Africa and to assess the association between such traumas and specific psychiatric disorders. It will also assess a broad range of risk factors and resources that may modify the association between exposure to human rights violations and mental health.

Ball-milling synthesis of biochar and biochar–based nanocomposites and prospects for removal of emerging contaminants: A review

Abstract: The ball-milling of carbon-based materials with nanoparticles is currently emerging as a promising cost-effective alternative method of producing nanocomposites with great surface characteristics. Biochar-based nanocomposites are effective in the adsorption of heavy metals, dyes and emerging organic contaminants in water and wastewater because of the combined benefits of biochar and nanoparticles. Contaminants of emerging concern are increasingly being detected in the environment and there is, therefore, an urgent need to develop nanotechnology-based multifunctional and highly efficient processes that can remove a wide range of these chemicalsmost of which are persistent and may bioaccumulate. To date, not many reviews are available on the use of the ball-milling method for engineering biochar-based nanocomposites. Ball milling (solid-state synthesis) is a process extensively used in industry to synthesize nanomaterials. Ball milling process produces small particle size as small as 10 microns, coupled with the advantages of continuous operation. Thus, this review article aims to provide an overview of the efficiencies of the ball-milled biochar-nanoparticle composite. Ball milling approach improves the physicochemical properties of biochar and biochar–nanoparticle composite such as total and micropore surface of biochar which in turns enhance their sorption abilities. Different adsorption mechanisms of biochar and modified biochar have been reported, which include physisorption, chemisorption, ion-exchange, pore-filling, hydrophobic effects and π-π electron donor-acceptor (π-π EDA) interactions.