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Background: One factor which is consistently highlighted in research on literacy is the lack of understanding of how literacy develops in the Southern-Bantu languages. In particular, little is known about spelling in the Southern-Bantu languages such as isiXhosa. Objectives: Through the use of an initial exploratory study and a conceptual replication study, we examined the relationships between reading, phonological awareness, and spelling in isiXhosa grade 3 learners. The initial exploratory study sought to describe the relationships between reading and spelling, and phonological awareness and spelling in a sample of 49 grade 3 isiXhosa learners. We then conceptually replicated this study with a larger sample of 200 grade 3 isiXhosa learners. We expected that both reading and phonological awareness would be related to spelling and that the strength of the relationship between reading and spelling, and phonological awareness and spelling would vary with spelling ability, due to the changes that occur in the development of spelling. Method: Cross-sectional, quantitative secondary data were used from two different projects to answer the research questions. Tasks of phonological awareness, oral reading fluency and spelling were developed and administered to the participants. Results: We found that reading was a replicable predictor of spelling for grade 3 isiXhosa learners and that phonological awareness was influential only at the mid-range of spelling performance. Conclusion: Our findings emphasise the importance of the reading-writing connection, and lend support for what has been found for other consistently written languages, adding to the growing body of knowledge of universal predictors of spelling development.

Multilingualism in education is encouraged in South Africa, and children are expected to become bilingual and biliterate during the early primary grades. Much focus has been placed on measuring literacy in children's first language, often the medium of instruction (MOI), and English, the language typically used as MOI from fourth grade. However, vocabulary development in African contexts is underexplored, owing to the cost of existing English standardized tests, and the comparatively fewer linguistically and contextually appropriate vocabulary assessments in African languages. To address this gap, we document the development of corpus-informed contextually appropriate tests of productive vocabulary in isiZulu, Siswati, and English, which were used for a project evaluation. The initial validation phase included 412 children. Both tests were reliable and were concurrently validated with reading comprehension tests in each language, and oral language skills in English. This study contributes to our understanding of the factors that affect the variation in vocabulary knowledge in an African context, including age, grade repetition, and vocabulary in the other language. Only English vocabulary was affected by the remote rural location of the school. We recommend some modifications to the tests before they are validated further in other populations.

Background: Many South African children attend African language medium of instruction (MOI) schools, learn English as an additional language and switch to English MOI three years later. There is still much to be researched about how a child's first and second language literacy develops over time in South Africa. Aim: This study aims to outline the first and second language skills at the start of Grade 1, which are associated with English Second Language literacy at the end of Grade 1 through the use of a longitudinal design. Setting: Data was collected from 80 predominantly rural no-fee isiZulu and Siswati MOI schools in Mpumalanga. Methods: A total of 1347 learners were randomly selected from these schools and were individually assessed on various first language (isiZulu or Siswati) and English skills at the start and end of Grade 1. Results: The data show that learners begin school with varying first and second language oral language proficiency levels, and most learners are pre-literate. Decoding skills improved over the year, but 45.7% and 35% of learners were still unable to read a first language or English word correctly in 1 min. Conclusion: The data confirm the importance of first language phonological awareness and letter-sound knowledge for later word-reading abilities in isiZulu, Siswati and English, as well as their importance for English spelling. The study highlights the importance of the systematic development of English oral proficiency during the Foundation Phase especially for rural children who are not exposed to English in their communities.

An adapted version of the Wechsler Preschool and Primary Scale of Intelligence--Third Edition (WPPSI-III) was administered to assess cognitive functioning among 1,253 5-year-old children from the Malnutrition and Enteric Disease (MAL-ED) study--an international, multisite study investigating multiple aspects of child development. In this study, the factor structure and invariance of the WPPSI-III were examined across seven international research sites located in Bangladesh, Brazil, India, Nepal, Pakistan, South Africa, and Tanzania. Using a multiple indicator multiple cause (MIMIC) modeling approach, the findings supported the validity of a fluid reasoning dimension (comprised of block design, matrix reasoning, and picture completion subscales) across each of the seven sites, although the scores were noninvariant. Accordingly, these scores are recommended for research purposes and understanding relationships between variables but not for mean comparisons or clinical purposes.

The Bayley's Scales of Infant and Toddler Development-Third Edition (Bayley-III) were used to measure the development of 24-month-old children (N = 1,452) in the Interactions of Malnutrition and Enteric Infections: Consequences for Child Health and Development (MAL-ED) study (an international, multisite study on many aspects of child development). This study examined the factor structure and measurement equivalence/invariance of Bayley-III scores across 7 international research sites located in Bangladesh, Brazil, India, Nepal, Pakistan, Peru, and South Africa. Exploratory and confirmatory factor analyses were used to identify the factor structure of Bayley-III scores. Subsequently, reliability analyses and item response theory analyses were applied, and invariance was examined using multiple-indicator, multiple-cause modeling. The findings supported the validity, but not invariance, of Bayley-III language scores at all seven sites and of the cognitive and motor scores at six sites. These findings provide support for the use of scores for research purposes, but mean comparison between sites is not recommended. Impact and Implications: In measurement, validity refers to the extent to which we are measuring what we intend to measure and the appropriateness of inferences we make based on our measurements. The validity of scores from measures often varies across cultures, and this study examined the validity of a measure of child development among children from sites in seven low- and middle-income countries. The findings indicate that the majority of the scores are valid for research, but measurement differences are evident such that it is not appropriate to compare mean scores across sites. [Co-written with the MAL-ED Network Investigators.]

Characteristics of temperament have been shown to predict aspects of personality and psychopathology. Approach temperament (i.e., sensitivity, reactivity, and behavioral disposition toward reward stimuli) may be a particularly salient predictor of developmental outcomes (e.g., Nigg, 2006; Shiner & Caspi, 2003). However, there is little research on approach temperament among children from low- and middle-income nations. This study examined the validity of an adapted version of the Infant Temperament Scale across eight international sites with a focus on approach temperament. Our sample included 1,933 infants from eight study sites in low- and middle-income nations: Bangladesh, Brazil, India, Nepal, Peru, Pakistan, South Africa, and Tanzania. The Infant Temperament Scale was translated and administered as a structured interview to caregivers at each site. Exploratory and confirmatory factor analyses were used to examine the factor structure of the scale, and multiple indicator multiple cause (MIMIC) modeling was used to examine invariance of scores across sites. The findings supported the validity of an approach temperament factor. Although the findings did not support the cross-cultural use of the entire Infant Temperament Scale among individuals from low- and middle-income nations in our sample, the supported approach temperament factor is a theoretically important subconstruct. Moreover, the inability to measure other aspects of temperament across cultures may have important implications for researchers interested in the nature of temperament. Implications and future directions are discussed. [Co-written with The MAL-ED Network Investigators.]

Abstract: Analyses of the Re–Os isotope system and PGE abundances have been used to investigate the timing and origin of mineralisation in the Vaal Reefs section of the Witwatersrand Basin, the world''s largest gold deposit. Consistent interelement PGE fractionation in both organic and sulphide phases intimately associated with gold mineralisation suggests that the Re–Os isotope system was fractionated during gold mobilisation. The Re–Os isotope data on organic separates intimately associated with the gold in this part of the basin indicate open system behaviour until ∼2.26±0.19Ga (2σ), of the order of 450Myr younger than the minimum age of sedimentation. The overlying Ventersdorp Volcanics preserve a Re–Os isochron age of 2.43±0.21Ga, ∼250Ma younger than their U–Pb zircon emplacement age. These data indicate substantial post-sedimentary noble metal mobility within portions of the Witwatersrand Basin. Re–Os model age calculations on Os-rich fractions suggest that noble metals were derived from a 3.0–3.1Ga terrain of granite–greenstone affinities, significantly younger than the Barberton Greenstone Belt. These data support a hybrid model involving post-depositional mobilisation of ancient, probably detrital, noble metals for the origin of mineralisation in this part of the Witwatersrand Basin. Such a model is applicable to other areas of gold mineralisation in the basin that display similar textural characteristics and geochemistry. [Copyright &y& Elsevier]

This paper reports the discovery of carbonic CH4-dominated fluid inclusions in two carbonate-hosted zinc-lead deposits in Griqualand West, South Africa. The primary carbonic inclusions were identified in coarse crystalline quartz of the main mineralisation stages at the Pering and Bushy Park deposits, hosted by Neoarchean dolostones of the Campbellrand Subgroup of the Transvaal Supergroup. The composition of the carbonic inclusions was determined from their low temperature phase behaviour during microthermometry and was confirmed with Raman microspectometry. It provides evidence for the presence of a highly reactive reducing agent (CH4) that may have been important during the mineralisation process. The carbonic inclusions and their coexistence with saline aqueous fluid inclusions allow the determination of the fluid temperature (200 to 240°C) and pressure (0.8 to 1.5 kbar) during mineralisation, suggesting that ore formation took place at 2.8 to 4.8 km depth under lithostatic pressure conditions. This is deeper than widely believed for Mississippi Valley-Type deposits, with which the Pering and Bushy Park deposits show many similarities. [ABSTRACT FROM AUTHOR]

Discusses evidence for microbially mediated manganese (Mn) precipitation during the late Paleoproterozoic in South Africa. Geologic and sedimentologic setting; Similarity of ancient oncoids to modern biogenic oncoids; Composition of Mn ores; Biogenic origin of oncoids.