Teacher as learner: a personal reflection on a short course for South African university educators

Higher education is understood to play a critical role in ongoing processes of social transformation in post-apartheid South Africa through the production of graduates who are critical and engaged citizens. A key challenge is that institutions of higher education are themselves implicated in reproducing the very hierarchies they hope to transform. In this paper, I reflect critically on my experiences of a course aimed at transforming teaching through transforming teachers. In this paper, I foreground my own positionality as a white female educator as I draw on feminist theorising to reflect on my experiences as a learner in the Community, Self and Identity course. I suggest that we need to teach in ways that are more cognisant of the complexities of the constraints on personal freedom in the past if we are to contribute to the development of social justice in the future.IS

Geochemistry and petrogenesis of the Etendeka volcanic rocks from SWA Namibia

The volcanic rocks of the Etendeka Formation from north-west SWA/Namibia have a present-day coverage of 70,000 km² and comprise a series of interbedded basalts, latites and quartz latites, together with four varieties of intrusive dolerite. Apart from one group of dolerites (regional dolerites) which have mineralogical and geochemical similarities to the Lesotho Formation lavas from the Central area, the Etendeka volcanics differ from all other Karoo volcanics by virtue of their Cretaceous age, stratigraphy, mineralogy, geochemistry, and range in mineralogical, elemental and isotopic compositions for the basaltic rocks

Micro-Raman study of crichtonite group minerals enclosed into mantle garnet

We report the first comprehensive micro-Raman study of crichtonite group minerals (CGM) as inclusions in pyropic garnet grains from peridotite and pyroxenite mantle xenoliths of the Yakutian kimberlites as well as in garnet xenocrysts from the Aldan shield lamprophyres (Russia). The CGM form (i) morphologically oriented needles, lamellae, and short prisms and (ii) optically unoriented subhedral to euhedral grains, either single or intergrown with other minerals. We considered common mantle-derived CGM species (like loveringite, lindsleyite, and their analogues), with Ca, Ba, or Sr dominating in the dodecahedral A site and Zr or Fe in the octahedral B site. The Raman bands at the region of 600–830 cm−1 are indicative of CGM and their crystal-chemical distinction, although the intensity and shape of the bands appear to be dependent on laser beam power and wavelength. The factor-group analysis based on the loveringite crystal structure showed the octahedral and tetrahedral cation groups with 18f and 6c Wyckoff positions, namely, dominantly TiO6 and to a lower extent CrO6, MgO4, and FeO4 groups, to be the major contributors to the Raman spectral features. The ionic groups with dodecahedral (M0) and octahedral (M1) coordination are inactive for Raman scattering while active in infrared absorption. A number of observed Raman modes in the CGM spectra are several times lower than that predicted by the factor group analysis. The noticed broadening of modes in the CGM Raman spectra may result from a combining of bands at the narrow frequency shift regions. Solid solution behavior, luminescence, and partial metamictization of the CGM may exert additional influence on the Raman band shape. The Raman spectral features showed CGM to be accurately identified and distinguished from other Ti-, Fe-, Cr-, and Zr-containing oxides (e.g., ilmenite or those of spinel and magnetoplumbite groups) occurring as accessory mantle minerals. © 2020 The Authors. Journal of Raman Spectroscopy published by John Wiley & Sons LtdRussian Science Foundation, RSF: 18‐77‐10062Council on grants of the President of the Russian FederationThis study was supported by the Russian Science Foundation (Grant 18‐77‐10062). The equipment of the Ural Center for Shared Use «Modern Nanotechnology», Ural Federal University, and the Analytical Center for Multi‐elemental and Isotope Research, IGM, was used. Sampling was supported by the Russian Federation state assignment project of IGM. We are grateful to Nikolai V. Sobolev for Samples O‐173, O‐39, and O‐264. Vladimir N. Korolyuk, Elena N. Nigmatulina (IGM), and Allan Patchen (UT) are highly appreciated for the help with EMP analyses. We express our sincere thanks to F. Nestola and an anonymous reviewer for their thorough reviews and helpful suggestions, and to C. Marshall for regardful editorial handling of the manuscript on every stage of its revision

The role of kidney uptake of Tc-99m pertechnetate during quantitation of gastric scintigraphy

[No abstract available]Articl

Oesophageal perforation as a complication of pulmonary tuberculosis in children

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Is there a role for 99mTc-HMPAO leucocyte scintigraphy in infective endocarditis?

Infective endocarditis is an important disease in developing countries. A combination of clinical findings, typical organisms cultured from blood, and specific echocardiographic features are used to establish the diagnosis. The diagnosis is often difficult because cultures are not always positive and transthoracic echocardiography lacks sensitivity and specificity, leading to delayed treatment or inappropriate therapy. As 99mTc-HMPAO-labelled leucocyte scintigraphy is used routinely to evaluate patients with suspected infectious processes, it was postulated that this technique might also aid in the diagnosis of infective endocarditis in patients with underlying chronic rheumatic heart disease or other valvular disease. Six patients were referred for 99mTc-HMPAO-labelled leucocyte scintigraphy. The white blood cells were labelled according to standard procedures. Whole-body planar imaging and single photon emission tomography of the chest area, with imaging at 30 minutes, 3 hours and 24 hours after the administration of the labelled leucocytes, were performed on all patients. All the scintigrams were negative. The reasons for the negative findings are not entirely clear, but probably reflect the pathological nature of vegetations, which consist mainly of masses of fibrin, clotted platelets and blood cell debris, containing the causative organisms. Leucocytes do not play a major role in the pathological process. Although only six patients were studied, it appears that 99mTc-HMPAO leucocyte scintigraphy is of little value in the evaluation of patients with infective endocarditis. A study after the administration of radiolabelled antibiotics may be of greater value and should be considered in these patients.Articl

Infective endocarditis: negative 99mTc-HMPAO leucocyte scintigraphy.

GesondheidswetenskappeInterne GeneeskundePlease help us populate SUNScholar with the post print version of this article. It can be e-mailed to: [email protected]

Single photon emission computed tomography v. planar imaging in recent myocardial infarction using technetium-99m pyrophosphate

Radionuclide imaging of the myocardium with technetium-99m-labelled pyrophosphate (PYP) is a sensitive method for the diagnosis of a recent (2-7 days old) myocardial infarct. Although the sensitivity of planar imaging with PYP is more than 95% for recent transmural infarcts, it varies between 30% and 95% in nontransmural infarcts. It has, however, been shown that single photon emission computed tomography (SPECT) considerably enhances the sensitivity of this technique in patients with proven non-transmural infarcts. In the present study SPECT is evaluated in patients with a doubtful diagnosis of a recent myocardial infarct. Ninety-nine consecutive patients, who were referred from a cardiology unit with an uncertain diagnosis of a recent myocardial infarction, were studied with routine planar and SPECT imaging with PYP. Images were obtained 3 hours after an intravenous injection of 600 MBq PYP. The images were viewed independently by 3 experienced nuclear medicine physicians in a retrospective analysis of the results. These were reported as positive, equivocal or negative for myocardial infarction. There were 30 patients with positive and 44 with negative images using both methods of imaging. Twenty-three patients with normal or equivocal images on the planar views were regarded as positive on the SPECT studies. The difference was highly significant (P < 0,001). SPECT considerably improved the sensitivity of PYP imaging in this series. It increased image quality, gave a much clearer delineation of the infarct and enhanced observer confidence during reporting. Furthermore, the method is non-invasive and inexpensive and should considerably shorten the hospital stay of many patients in whom a firm diagnosis of a recent myocardial infarction could not be made by conventional means.Articl