Bioassessing the impact of water quality on the health and parasite composition of Oreochromis Mossambicus at the Phalaborwa Industrial Complex (PIC) and the barrage (Olifants river) in the Limpopo Province,South Africa.

Thesis (M.Sc)--University of Limpopo, 2008.Three sites at the Phalaborwa Industrial Complex (PIC) and one site at the Phalaborwa Barrage in the Olifants River were selected to illustrate the possible influence of different water quality parameters on the health and parasite composition of the Mozambique tilapia (Oreochromis mossambicus). Ten fish were collected seasonally at each site using gill nets of different mesh sizes. Selected water quality variables were determined at all the sites to establish possible differences in water quality between the sites. Hosts were examined for mobile ectoparasites, weighed and measured. Blood samples were drawn and skin smears were made. Fish were killed, dissected and all external and internal organs were examined as prescribed in the fish health assessment index (HAI). The condition factor was determined for each fish population from the different sites. All parasites were collected, fixed and preserved using standard methods. A parasite index(PI), abundance, prevalence and mean intensity of the parasite infestations were calculated.Results obtained for the system variables (pH, water temperature and dissolved oxygen) indicated that the pH levels and water temperature fell within the target water quality range (TWQR) for aquatic ecosystems, but the dissolved oxygen recorded during most of the surveys were below 5mg O2 l-1 which may adversely affect the functioning and survival of biological communities. The mean turbidity values were high at sites A, C and D (caused by fine particles such as silt, clay and organic matter). The total dissolved solids (TDS) and the electrical conductivity (EC) were very high at sites B and C throughout the study. The total water hardness and salinity were also very high at sites B and C which can be attributed to the mine tailings water as well as the geology of the region. The cations (calcium, magnesium and potassium) and anions (chloride, fluoride and sulphate) were above the TWQR for aquatic ecosystems at all sites. The fluoride and sodium levels were high at sites B and C. All the major ions contributed significantly to increased levels of TDS, salinity and EC at sites B and C. The nitrogen and phosphate levels indicated that there was an influx of nutrients into the four sampling sites at varying degrees, which can have an effect on eutrophication conditions at the sampling sites. Trace and heavy metal concentrations differed significantly between all the sites. Aluminium, iron and manganese levels were within the TWQR for aquatic ecosystems at all sites. Copper, lead and zinc levels were above the TWQR and sometimes above the chronic and acute effect values for aquatic ecosystems throughout the study (except for lead concentrations at site A). Thus, the mining activities do affect the water quality at sites B and C adversely in terms of the dissolved salts, nutrients and trace and heavy metals (with the water at site C more impacted than that of site B). The toxicity of some metals is however, dependant on the pH (if it changes to be more acidic, some metals may become toxic) and water hardness of the specific site. The lowest population HAI values (indicating healthier fish populations) were mostly recorded from sites A and D (the sites with better water quality) and the highest at site C(the site with poorer water quality) for three surveys. The high HAI values at site C can mainly be attributed to liver discoloration and abnormal haematological parameters. The fish condition factor values ranged from 0.92 to 1.2 with the lowest mean value recorded at site A and the highest mean value recorded at site B. But, the condition factors indicated that the fish from all sites were generally in good health. The values attained for the haematological parameters, liver discolorations, fins (due to parasitic infestation),abnormal gills, as well as the type of parasites present in/on the fish, were the most indicative parameters in the HAI. No abnormalities in the kidneys, opercules and spleens of fish were observed at any of the four sampling sites during this study. Results from the HAI thus indicated that the fish population from site C was more affected by the water quality (with a higher HAI) compared to the fish populations from the other sites. Also, dissimilar water quality at the different sites affected the health of fish differently. The results recorded for the HAI of the different fish populations thus substantiate the results obtained from the water analysis, indicating that fish from site C (with the poorest water quality) was more affected by their environment. The parasites recorded from O. mossambicus were all site-specific and seem to be moderately influenced by the water quality of the different sites. Some groups, e.g. monogeneans were more affected by the differences in water quality than other parasitic groups. The following ectoparasites were recorded: Cichlidogyrus sp. from the gills and Lernaea cyprinacea and Argulus japonicus from the skin. Endoparasites included digenean larvae from the skin (“black spot”) and gills, Neutraclinostomum larvae in the branchial region, Diplostomum metacercariae from the eyes and swimbladder,Diplostomum tregenna from the brain, dilepidid cestode larvae from the liver and outer surface of the intestine, Contracaecum larvae from the body cavity and sinus venosus of the heart, adult acanthocephalans from the intestine, and pentastomatid larvae of two genera (Subtriquetra rileyi and Alofia sp.) from the swimbladder. The hypothesis that the number of ectoparasites will be lower in more polluted water and the number of endoparasites will be higher was well supported for O. mossambicus at all sites except at site C during Spring survey. The PI for endoparasites was higher at all the mine sites (except during Spring) but similar results were also obtained at sites A and D (the less impacted sites). However, all sites tested during this study were impacted to a lesser or higher degree and the PI for endoparasites can thus be higher at all sites. Some ectoparasites (i.e. Lernaea cyprinacea) were present in high numbers at the more polluted site (site C), but the abundance of monogeneans (also ectoparasites) was most of the time lower at sites B and C, suggesting that monogeneans have been strongly influenced by the poorer water quality at these sites. The specific water parameter/s that influenced the abundance of certain ectoparasites needs further investigation which would most probably best be tested under controlled laboratory conditions. In conclusion, all sites sampled during this study were contaminated to some degree with sites B and C more impacted than the other two sites. The water quality results thus confirmed the results obtained using the HAI and to a lesser extent, the PI. The water quality differed between the four sites and had dissimilar impacts on the health of O. mossambicus and the prevalence of some parasites at the different sites.the National Research Foundation,the Sasol Nitr

Risk factors in a rural setting as expressed by youth

The purpose of this secondary data analysis study was to describe what youth in a rural setting expressed as risk factors by sampling data from an existing ten year data set generated by academic service learning (ASL) students delivering educational psychology services to Grade 9 clients in a rural schools. Rurality theory served as theoretical framework and phenomenology was used as metatheory. Data sources, indicative of youth-expressed risk were purposively sampled from 2012 to 2015 cohorts and included data sources from clinical client files (n=64, client files, male client files =32, female client files =32; 2012: ASL: n=16, male=10, female=6; 2013: n=16, male=8, female=8; 2014: n=16, male=7, female=9; 2015: n=16, male=7, female=9). The data sources) included clients’ projective and expressive instruments, as well as ASL students’ (i) quadrant maps (analysing the client socioeconomic contexts), and (ii) reflection notes. Following inductive thematic analysis the following risk themes emerged: low socioeconomic status (Lack of resources, Unemployment - limited job opportunities, Poverty - household income), lack of community safety (Crime, and Game (wildlife), negative objective and subjective health and wellbeing (Bullying, Loss - Grief and bereavement, Illness, and Limited self-regulation), as well as multiple barriers to education (Language of learning and teaching (LOLT), Lack of learning resources, Teacher proximity constraints, Absent parents and Peer pressure). Although these risk factors are known to act as barriers to development for young people this study contributes by indicating these as particular risk factors that young people themselves signify as pertinent challenges they need to address. Young people were silent on racism, neglect and conservatism as risk factors present in rurality theory.Dissertation (MEd)--University of Pretoria, 2017.Educational PsychologyMEdUnrestricte

Entrenching performativity or enhancing pedagogy: Addressing the challenge of assessment policy and practice

The focus of the South African Education Research Association’s Assessment and Testing Special Interest Group (SIG) is to contribute to current initiatives and debates pertaining to the development and implementation of assessment systems for improving learning and teaching. In particular, the SIG’s members aim to address dominant performativity discourses impacting schools and universities by (1) providing a common understanding of the purpose and use of assessment, (2) locating the different assessment applications across the broader system within which learning and teaching occurs, and (3) highlighting recent initiatives impacting on assessment policy and practices. We think it essential to highlight critical policy and practice questions, while simultaneously acknowledging ongoing challenges for implementing enabling assessment systems that support the specific pedagogical needs of learners, teachers, students, and lecturers. Notwithstanding the complexities ofeffecting change, increasing discourse on, as well as relevant critique of, policies and practices that fail to improve learning and teaching, enhances possibilities for implementing enabling assessment policy and practice that seek to address the elusive challenge of equity and quality within the education system.&nbsp

Pre-Service Teachers Perceptions of Inclusive Education at a University of Technology in South Africa

Currently inclusive education is one of the contemporary issues in education in both developed and developing countries though some countries are struggling to effectively implement it Research has demonstrated that inclusive education can only be firmly implemented if there is a proper curriculum appropriate resources and good teacher pedagogical and knowledge skills It is therefore imperative for teacher education to empower pre-service teachers with necessary knowledge and pedagogical skills to teach inclusively The article focused on Bachelor of Education B Ed 3rd year student teachers perceptions and views regarding inclusive education curriculum implementation at a University of Technology in South Africa UoT A qualitative research approach was employed with a case study design Purposive sampling was used to select 120 participants from 3rd year Bachelor of Education students from a University of technology in South Africa Structured focus group interviews were used to collect data and data was analysed using thematic analysi

Tunable Rh(I) Fischer carbene complexes for application in the hydroformylation of 1-octene

AbstractThe preparation of a series of rhodium(I) complexes coordinated by various electronically tuneable Fischer carbene (FC) ligands, is reported. The Rh(I) metal complexes’ electronic properties could readily be modulated by variation of a p-N,N-dimethylaniline moiety with a ruthenocenyl substituent, or alternatively, substituting the carbene O-heteroatom for an amino-group. The electronic properties of the complexes were evaluated, and it was determined from the Tolman electronic parameters that the donor-ability of the FC ligands are comparable to N-heterocyclic carbenes. Furthermore, the facile control of the electronic properties of the complexes was demonstrated by mild oxidation of a ferrocenyl aminocarbene rhodium(I) complex, yielding the corresponding ferrocenium rhodium(I) complex cation. Finally, the complexes were evaluated as catalyst precursors for the hydroformylation of 1-octene.Abstract The preparation of a series of rhodium(I) complexes coordinated by various electronically tuneable Fischer carbene (FC) ligands, is reported. The Rh(I) metal complexes’ electronic properties could readily be modulated by variation of a p-N,N-dimethylaniline moiety with a ruthenocenyl substituent, or alternatively, substituting the carbene O-heteroatom for an amino-group. The electronic properties of the complexes were evaluated, and it was determined from the Tolman electronic parameters that the donor-ability of the FC ligands are comparable to N-heterocyclic carbenes. Furthermore, the facile control of the electronic properties of the complexes was demonstrated by mild oxidation of a ferrocenyl aminocarbene rhodium(I) complex, yielding the corresponding ferrocenium rhodium(I) complex cation. Finally, the complexes were evaluated as catalyst precursors for the hydroformylation of 1-octene

Rhodium(I) ferrocenylcarbene complexes : synthesis, structural determination electrochemistry and application as hydroformylation catalyst precursors

New examples of the rare class of rhodium(I) ferrocenyl Fischer carbene complexes 1–8, [Rh(LL)Cl{C(XR)Fc}] [LL = cod, (CO)2, (CO, PR3) (R = Ph, Cy or OPh) and (CO, AsPh3); XR=OEt or NHnPr] were prepared, and the electronic effects of co-ligands and alkoxy vs. aminocarbene substituents were investigated by spectroscopic and electrochemical methods. The molecular structures of complexes 1, 2 and 4–6 were confirmed by single crystal X-ray diffraction. The use of the complexes 1–8 as homogeneous catalysts for the hydroformylation of 1-octene was demonstrated, and the influence of the carbene substituents and co-ligands on the activity and regioselectivity of the catalysis evaluated. Finally, the stability of the Rh-Ccarbene bond of complex 1 under hydroformylation conditions was confirmed with 13C NMR experiments.National Research Foundation, South Africa (D.I.B., Grant numbers 87890, 92521 and 92581) and Sasol Technology R&D Pty. Ltd.,South Africa, and the NRF-DST Centre of Excellence in Catalysis (c* change ). A generous loan of rhodium trichloride hydrate from Johnson Matthey/AngloAmerican Platinum Ltd. .http://pubs.acs.org/journal/orgnd72016-12-31hb201

The construction of Foundation Phase Mathematics Pedagogy through Initial Teacher Education Programmes

The focus of this study is on the Foundation Phase mathematical and pedagogical knowledge construction. This study is about how two lecturers and a number of final year B.Ed. Foundation Phase student teachers construct Foundation Phase mathematical and pedagogical knowledge during the initial teacher education programme. The initial B.Ed. Foundation Phase teacher education provides student teachers with different mathematical knowledge for teaching. A Foundation Phase mathematics pedagogical knowledge construction framework was utilised to generate and analyse data. The Foundation Phase mathematics pedagogical knowledge construction framework is developed with the assumption that the integrated learning knowledge and the process of pedagogical reasoning action is a continuous process. Furthermore, it is assumed that student teachers’ active participation in their learning and paddling through the pedagogical reasoning action process, leads to the construction of Foundation Phase mathematical pedagogical knowledge. The study utilised a qualitative case study design to investigate how two initial teacher education programmes construct Foundation Phase mathematical pedagogical knowledge in their programme to prepare student teachers to teach Foundation Phase mathematics. Data were collected from Foundation Phase mathematics lecturers through semi-structured interviews, focus group interviews with final year Foundation Phase student teachers as well as document analysis from the institutions to achieve triangulation. Data analysis and findings were based on themes and categories that emerged. The findings suggest that Foundation Phase mathematical and pedagogical knowledge construction is an interconnected and continuous process that includes different types of knowledge and pedagogical reasoning.Dissertation (MEd)--University of Pretoria, 2014.tm2015Educational PsychologyMEdUnrestricte

The influence of obstacles on non-linear waves in stratified fluids

SIGLEAvailable from British Library Document Supply Centre- DSC:DX180546 / BLDSC - British Library Document Supply CentreGBUnited Kingdo