67 research outputs found

    Epitaxial deposition of silver ultra-fine nano-clusters on defect-free surfaces of HOPG-derived few-layer graphene in a UHV multi-chamber by in situ STM, ex situ XPS, and ab initio calculations

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    The growth of three-dimensional ultra-fine spherical nano-particles of silver on few layers of graphene derived from highly oriented pyrolytic graphite in ultra-high vacuum were characterized using in situ scanning tunneling microscopy (STM) in conjunction with X-ray photoelectron spectroscopy. The energetics of the Ag clusters was determined by DFT simulations. The Ag clusters appeared spherical with size distribution averaging approximately 2 nm in diameter. STM revealed the preferred site for the position of the Ag atom in the C-benzene ring of graphene. Of the three sites, the C-C bridge, the C-hexagon hollow, and the direct top of the C atom, Ag prefers to stay on top of the C atom, contrary to expectation of the hexagon-close packing. Ab initio calculations confirm the lowest potential energy between Ag and the graphene structure to be at the exact site determined from STM imaging

    Sustainable development and African local government: can electronic training help build capacities?

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    A recent study carried out by European and African organizations into the potential for electronic distance training (EDT) on sustainability in African local governments concluded that EDT was both 'useful and feasible'. This article reflects on some of the theoretical and practical implications of that study. It focuses on the connection between learning and sustainability and how EDT programmes might be designed and promoted. The paper argues that, while resource issues and poor access to Information and Communication Technologies (ICTs) create considerable constraints and point to the need for policies to improve access, in general the most important factors for successful capacity building relate to the design of learning programmes that take account of the work contexts and skill and capability requirements of those targeted as learners. 'Useful' and 'feasible' depend on (i) how work-based and work-related learning processes are understood and (ii) the conditions to promote learning within African local government. Keywords: Africa; Electronic distance training; Local government; Sustainability; Workplace learnin

    Carbon nanotube-enhanced photoelectrochemical properties of metallo-octacarboxyphthalocyanines

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    The photoelectrochemistry of metallo-octacarboxyphthalocyanines (MOCPc, where M = Zn or Si(OH)2) integrated with MWCNTs for the development of dye-sensitized solar cells (DSSCs) is reported. The DSSC performance (obtained from the photo-chronoamperometric and photo-impedimetric data) decreased as ZnOCPc > (OH)2SiOCPc. The incorporation of the MWCNTs on the surface of the TiO2 film (MOCPc–MWCNT systems) gave higher photocurrent density than the bare MOCPc complexes. Also, from the EIS results, the MOCPc–MWCNT hybrids gave faster charge transport kinetics (approximately three times faster) compared to the bare MOCPc complexes. The electron lifetime was slightly longer (ca. 6 ms) at the ZnOCPc systems than at the (OH)2SiOCPc system (ca. 4 ms) meaning that the presence of the MWCNTs on the surface of the TiO2 film did not show any significant improvement on preventing charge recombination process

    The impact of physician education regarding the importance of providing complete clinical information on the request forms of thrombophilia-screen tests at Tygerberg hospital in South Africa

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    CITATION: Abdullah, I., Jafta, A. D. & Chapanduka, Z. C. 2020. The impact of physician education regarding the importance of providing complete clinical information on the request forms of thrombophilia-screen tests at Tygerberg hospital in South Africa. PLoS ONE, 15(8):e0235826, doi:10.1371/journal.pone.0235826.The original publication is available at https://journals.plos.org/plosone/Publication of this article was funded by the Stellenbosch University Open Access FundBackground: Thrombophilia-screen tests are specialised haemostasis tests that are affected by numerous unique patient variables including the presence of acute thrombosis, the concomitant use of medication and patient demographics. Complete information on the request form is therefore crucial for the haematological pathologist to make patient-specific interpretation of patients’ results. Objectives: To assess the completeness of thrombophilia-screen test request forms and determine the impact of provision of incomplete information, on the interpretive comments generated by reporting haematological pathologists. To assess the impact of an educational session given to clinicians on the importance of providing all the relevant information on the request forms. Method: Two retrospective audits, each covering 3 months, were performed to evaluate the completeness of demographic and clinical information on thrombophilia-screen request forms and its impact on the quality of the interpretive comments before and after an educational intervention. Results: One hundred and seventy-one request forms were included in the first audit and 146 in the second audit. The first audit revealed that all 171 thrombophilia-screen request forms had complete patient demographic information but none had clinical information. Haematological pathologists only made generic comments which could not be applied to a specific patient. The second audit, conducted after a physician educational session, did not reveal any improvement in the clinical information provision by the test-ordering physicians. This was reportedly due to the lack of space on the request form. The interpretive comments therefore remained generic and not patient-specific. Conclusion: Physicians’ failure to provide relevant clinical information made it impossible for pathologists to make patient-specific interpretation of the results. A single physician education session did not change the practice, reportedly due to the inappropriate design of the test request form. Further studies are required to investigate the impact of an improved request form and the planned electronic test requesting.https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0235826Publisher's versio

    Developing an Empowerment Theology: TST 121

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    Developing an Empowerment Theology: TST 121, Supplementary examination February 2010

    Developing an Empowerment Theology: TST 121

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    Developing an Empowerment Theology: TST 121, Supplementary examination February 2010

    Empowerment by Hope: TST 221

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    Empowerment by Hope: TST 221, degree examination November 2009

    Apostolic Fathers: TCH 501

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    Apostolic Fathers: TCH 501, honours examination November 2009

    History of Christianity in South Africa in the 20th Century: TCH 221

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    History of Christianity in South Africa in the 20th Century: TCH 221, supplementary examination January 2010

    Apostolic Fathers: TCH 501

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    Apostolic Fathers: TCH 501, honours examination November 2009
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