1,084 research outputs found

    The viruses of vervet monkeys and of baboons in South Africa

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    A Thesis Submitted to the Faculty of Medicine University of the Witwatersrand, Johannesburg for the Degree of Doctor of MedicineIn this thesis are presented briefly the results of studies extending over the period 1955 to 1974. The use of vervet monkeys in South Africa for the production and testing of poliomyelitis vaccine made acquaintance with their viruses inevitable; and the subsequent introduction of the baboon as a laboratory animal of major importance also necessitates a knowledge of its viral flora. Since 1934 when Sabin and Wright described the B Virus which was recovered from a fatal human infection contracted as the result of a macaque monkey bite, numerous viral agents have been isolated from monkeys and baboons. In the United States of America, Dr. Robert N. Hull initiated the classification of simian viruses in an SV (for Simian Virus) series according to cytopathic effects as seen in unstained infected tissue cultures. In South Africa, viruses recovered from monkeys and baboons were designated numerically in an SA (for Simian Agent) series on the basis of cytopathic changes seen in stained preparations of infected cells. Integration of these two series is in progress. Simian viruses in South Africa have been recovered mainly through the inoculation of tissue cultures with material obtained by means of throat and rectal swabs, and also through the unmasking of latent agents present in kidney cells prepared as tissue cultures. Some evidence concerning viral activity has been derived from serological tests. In this thesis the classification of simian viruses later proposed by Dr. Hull in 1968 has been adopted. This Ill comprises five categories based on nucleic acid type and strandedness, and on' ether sensitivity. It has not been possible to provide conclusive proof for the inclusion of a number of South African viruses in the categories to which they have been assigned under this scheme, but the available evidence suffices to indicate that representatives of the five main categories occur in South Africa. Some viruses found in this country are recognized as prototype strains in the internationally recognized classification of simian viruses, and one vervet adenovirus has been widely distributed and studied for its oncogenic properties. The herpesvirus SA8 is sufficiently closely related to the dangerous B Virus of macaques to warrant extreme care in the handling of non-human primates. This virus has been recovered from baboons as well as vervet monkeys. It is becoming evident that viruses recovered from one species may eventually be found to be more common in another species. In South Africa much remains to be done in the field of simian virology, and in this thesis are indicated techniques which could be further exploited and expanded to increase our knowledge of this group of potentially dangerous viruses.IT201

    The photospheric solar oxygen project: III. Investigation of the centre-to-limb variation of the 630nm [OI]-NiI blend

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    The solar photospheric abundance of oxygen is still a matter of debate. For about ten years some determinations have favoured a low oxygen abundance which is at variance with the value inferred by helioseismology. Among the oxygen abundance indicators, the forbidden line at 630nm has often been considered the most reliable even though it is blended with a NiI line. In Papers I and Paper II of this series we reported a discrepancy in the oxygen abundance derived from the 630nm and the subordinate [OI] line at 636nm in dwarf stars, including the Sun. Here we analyse several, in part new, solar observations of the the centre-to-limb variation of the spectral region including the blend at 630nm in order to separate the individual contributions of oxygen and nickel. We analyse intensity spectra observed at different limb angles in comparison with line formation computations performed on a CO5BOLD 3D hydrodynamical simulation of the solar atmosphere. The oxygen abundances obtained from the forbidden line at different limb angles are inconsistent if the commonly adopted nickel abundance of 6.25 is assumed in our local thermodynamic equilibrium computations. With a slightly lower nickel abundance, A(Ni)~6.1, we obtain consistent fits indicating an oxygen abundance of A(O)=8.73+/-0.05. At this value the discrepancy with the subordinate oxygen line remains. The derived value of the oxygen abundance supports the notion of a rather low oxygen abundance in the solar hotosphere. However, it is disconcerting that the forbidden oxygen lines at 630 and 636nm give noticeably different results, and that the nickel abundance derived here from the 630nm blend is lower than expected from other nickel lines.Comment: to appear in A&

    South African congenital disorders data, 2006 - 2014

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    Background. The National Department of Health in South Africa (SA) routinely collects congenital disorder (CD) data for its national CD surveillance system. The current system has been implemented since 2006, but no reports on the data collected, methodology, achievements or challenges have been published to date.Objectives. To ascertain the effectiveness of the current national CD surveillance system and its implementation.Method. A descriptive, retrospective study using an audit of the current database was undertaken to evaluate the number of notifications received, types of CDs reported and the quality of reporting across SA for data received from 2006 to 2014.Results. A total of 14 571 notifications were received, including 13 252 CDs and 1 319 zero notifications, across all nine provinces. Commonly reported CDs included Down syndrome, cleft lip and palate, talipes equinovarus, neural tube defects and albinism.Conclusions. The major challenges identified included erratic compliance by health facilities and a lack of healthcare providers trained in human genetics related to CDs. This has led to misdiagnosed and undiagnosed CDs, collectively resulting in under-reporting of cases by >98% during the review period. Owing to limited human and financial resources, it is recommended that the surveillance system be modified into an electronic format. This should be piloted alongside relevant training in specific sentinel sites, to improve data coverage and quality for further evaluation

    Illness caused by Sindbis and West Nile viruses in South Africa

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    Research contract relationship between a large industry partner and South African universities.

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    We propose and evaluate a contractual structuring instrument (in the form of a Framework Research Agreement) in support of research collaboration partnerships between universities and large industry, specifically for the case of large industry in the South African context. This study includes one large South African originated industry (as the pioneer of concluding Framework Research Agreements with several universities) and multiple South African universities, and stretches over several decades. This study was done within the broader context of the challenges and benefits experienced by both industry and university in the academic engagement sphere of industry–university collaboration. By providing insight from both industry and university perspectives, factors impacting on academic engagement (with specific emphasis on the legislative framework, contractual aspects, institutional research contract practices and institutional risks), are considered and discussed. Recommendations are made for improved industry–university collaboration by sharing experiences from the industry and universities on challenges faced, managing the expectations and proposing mechanisms to support constructive research collaboration through a mutually beneficial contractual framework instrument.Significance:• A novel Framework Research Agreement as a contractual instrument was developed and pioneered by the industry partner with several South African universities, to create a transparent framework based on fair contracting and determinable remuneration principles.• This study specifically highlights the need for a contractual instrument, in which the intention is to build a long-term contractual relationship to support industry–university collaboration and academic engagement within the existing South African legislative framework.• It further draws attention to research contract management practices and contractual aspects, which until now have been largely ignored in industry–university collaboration and academic engagement frameworks of this kind

    Die gebruik van 'dat' as verbindingswoord in Afrikaans, met verwysing ook na die gebruik in Middel-Nederlands, sestiende- en sewentiende-eeuse en hedendaagse Nederlands, en in Engels

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    Proefskrif (M.A.) -- Universiteit van Stellenbosch, 1966.No abstract availabl

    South African congenital disorders data, 2006 - 2014

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    Background. The National Department of Health in South Africa (SA) routinely collects congenital disorder (CD) data for its national CD surveillance system. The current system has been implemented since 2006, but no reports on the data collected, methodology, achievements or challenges have been published to date.Objectives. To ascertain the effectiveness of the current national CD surveillance system and its implementation.Method. A descriptive, retrospective study using an audit of the current database was undertaken to evaluate the number of notifications received, types of CDs reported and the quality of reporting across SA for data received from 2006 to 2014.Results. A total of 14 571 notifications were received, including 13 252 CDs and 1 319 zero notifications, across all nine provinces. Commonly reported CDs included Down syndrome, cleft lip and palate, talipes equinovarus, neural tube defects and albinism.Conclusions. The major challenges identified included erratic compliance by health facilities and a lack of healthcare providers trained in human genetics related to CDs. This has led to misdiagnosed and undiagnosed CDs, collectively resulting in under-reporting of cases by >98% during the review period. Owing to limited human and financial resources, it is recommended that the surveillance system be modified into an electronic format. This should be piloted alongside relevant training in specific sentinel sites, to improve data coverage and quality for further evaluation
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