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Radiation induced lens changes and development of a radiation safety framework for interventionalists
No full textBackground: Ionising radiation (IR) is a modality that is increasingly being used in diagnostic,
prognostic, therapeutic and interventional procedures. The health effects due to IR exposure
can be deterministic or stochastic. Deterministic effects refer to effects that are seen at a
minimal threshold level. These effects include skin burns and cytopaenia. Stochastic effects
refer to effects where a minimum threshold is not evident. These include carcinomas and
recently cataracts are thought to fall into this group. Interventionalists are at increased risk
of developing cataracts due to IR exposure.
The use of personal protective equipment (PPE) is essential to mitigate against the effects of
IR on the eyes. Lead glasses, lead visors and ceiling suspended screens are essential for
protecting the eyes of radiation healthcare workers (HCWs) in the catheterisation laboratory.
PPE is often not readily available and interventionalists are notoriously non-compliant with
donning PPE, especially lead glasses. They do not consistently wear their dosimeters either.
Essential to reducing the risk of cataracts associated with IR is to ensure that education and
training on radiation safety is formalised in the training of interventionalists and that there is
ongoing reinforcement of this training.
Creating and sustaining a culture of radiation protection (CRP) is essential to changing
attitudes and behaviour towards radiation safety practices. A CRP ensures better patient
safety and improves quality of care.
Methods: This was a cross sectional prospective study that used multiple methods to
address the research question. There was a qualitative and quantitative component. The
qualitative component used individual interviews and group interviews to understand
interventionalists’ perceptions about radiation and its effects on their health; to garner
insight to their training in radiation safety; and to make meaning of how they understood
what a CRP was. The quantitative components included a slit lamp examination and the
completion of a survey. We compared a group of doctors not routinely occupationally exposed to IR to a group of interventionalists that are occupationally exposed to IR. There
was no randomisation. Participation was voluntary and participants granted informed
consent. The study was approved by an ethics committee.
Results: The prevalence of cataracts possibly associated with IR exposure was 18.8% in the
exposed group and the prevalence of posterior sub-capsular (PSC) cataracts in this group was
5.9%. PSC cataracts were 2.2 times more likely to occur in the exposed compared to the
unexposed group.
Lead glasses were consistently used by 10.2% of the interventionalists. Females were 4.3
times more likely to report that PPE was not available. Qualitative data showed that
interventionalists had a culture where PPE such as lead aprons were consistently used but
lead glasses were not a priority. Participants had poor knowledge of the dose limits and they
did not consistently use dosimeters.
There was a dearth of radiation protection training for interventionalists in South Africa.
Radiologists received dedicated teaching on radiation safety while cardiologists did not
always receive teaching on the topic. This was especially true for cardiologists. Participants
generally agreed that there was a gap in their education and training in radiation safety
training. Only 44.1% of participants thought their training was adequate. The majority of
participants (95.4%) indicated that they wanted radiation safety training as part of their
curriculum.
A CRP was a strong theme that emerged as a conduit to creating a culture of radiation safety
and participants supported the notion of developing a better CRP to promote radiation
safety.
Conclusion: IR exposure remains a high risk in the cath. lab exposing interventionalists to the
risk of developing cataracts. This can be mitigated by improving training radiation safety and
encouraging utilisation of PPE. Developing and sustaining a CRP is essential to improving
radiation safety in the cath. lab.SA HeartDiscovery FoundationSouth African Medical Research Counci
Saturday night at the Speedway: class, race, gender and a ‘lynching’
No full textThis paper will reflect on some contemporary reenactments of whiteness by a white subaltern crowd
attending an oval track speedway meeting in central South Africa in 2017. It will also consider my role as
ethnographer/observer, this latter aspect positioning the paper as a kind of ‘gonzo-ethnography’. I tracked
several individuals including an ‘organic comedian’, a number of women and some children through what
turned out to be a key event at the night’s sport, an act of crowd violence directed at three Bangladeshi
men. This episode was spontaneous, populist and bottom-up, with evidence of strong gendered roles. It
can best be described as a kind of organized disorder as the three racial outsiders were isolated, humiliated, and stripped of the veneer of common humanity; in other words, it bore the characteristics of a lynching, albeit in symbolic form. This carnival rendering of violence was central to the identity and coherence of the crowd that night. The violence on show was ironically of a kind which the apartheid state itself sought to police and prohibit among subaltern whites from as early as the 1950s, reminding us once again that whiteness, was never homogeneous or without internal tensions and fractures.Publisher's versio
South African teachers' concerns and levels of use of practical work in the physical sciences curriculum and assessment policy statement
No full textIn many countries across the world, a notable portion of the science curriculum involves learners conducting practical work. The physical sciences Curriculum and Assessment Policy Statement (CAPS) of South Africa (2011) advocates for a scientific inquiry approach where hands-on practical activities are used to develop explanations and predictions of events in the environment (Department of Basic Education, [DBE], 2011). CAPS (ibid) further argues that investigative skills in addition to process skills such as classifying, measuring, formulating models, hypothesising, communicating, analysing conclusions and recognising and monitoring variables should be developed in learners. One of the recommended formal assessments for the FET band (grades 10–12) is for learners to have the opportunity to perform one or more practical tasks during the course of each term.
The demand to teach practical and inquiry skills would be a tall order for most teachers under any circumstances. The South African context, as a developing country with limited classroom resources, adds a further complicating dimension in relation to the implementation of practical work in the curriculum. Furthermore, the change in the focus of the curriculum, as embodied in CAPS with its emphasis on problem-based practical activities, represents a new challenge for many teachers in South Africa who may be used to a more content and information loaded curriculum. These teachers may also have limited experience with practical work in their own teacher preparation programmes. Many teachers are therefore likely to have various concerns with the new focus on doing increased amounts of practical work in the physical sciences CAPS curriculum, even as they try their best to implement it as required by the authorities. This study used the concerns-based adoption model (CBAM) to uncover and track teachers’ concerns and levels of use of the new practical requirement of the physical sciences CAPS in one district of South Africa, namely the Motheo district in the Free State.
The study used a mixed-methods research approach with questionnaires, semi-structured and focus group interviews as well as lesson observations as data sources to understand the concerns that physical sciences teachers have regarding CAPS practical work and the level at which this component is implemented. The findings are reported in two articles that address different research questions. The first article, which is quantitative in nature, explores the concerns that physical sciences teachers in the Motheo district of South Africa have regarding practical work.
The findings suggest that teachers’ concerns are inclined towards management issues by focusing on overcoming time constraints and the lengthy curriculum. Furthermore, teachers place low importance on the effects of practical work on learners’ performance, with limited attempts for improvement. Respondents have management concerns that mainly constituted dealing with demanding day-to-day organisational tasks regarding CAPS practical work. Teachers have a desire to collaborate but this is not significantly evident. This suggests that despite the challenges experienced by teachers with practical work, circumstances are minimally improved.
The second article is qualitative in nature and examines the extent of implementation of CAPS practical work by physical sciences teachers. The findings uncover the level at which physical sciences teachers implement CAPS practical work according to CBAM. Findings show that teachers operate significantly at the mechanical and routine levels, while the refinement level is at a less significant degree. This revealed that while participants employ teacher-centred methods during practical work, learner engagement is limited. Learners only watch what the teachers do and no active participation was observed. Teachers do not seem to implement CAPS practical work as intended by policymakers.
Teachers are faced with a shortage of time and resources. Limited content and pedagogical content knowledge also contribute to nominal implementation of CAPS practical work. Moreover, teachers use traditional teaching strategies when carrying out practical work. This leaves them with little room for innovation with the objective of engaging learners. With the application of triangulation, the results of this investigation show that teachers’ concerns affect the implementation of CAPS practical work. It was important to triangulate the research instruments and data to ensure validity and reliability as well as compare and verify the data.
The study recommends that physical sciences teachers need to collaborate more with one another. The results presented here may facilitate improvements in the professional development of physical sciences teachers concerning experimental work. Recommendations include effective teacher collaboration, introduction of laboratory assistants, appropriate professional development and quality planning. An implication for education managers is the need for active monitoring, evaluation and support of practical work.National Research Foundation (NRF
NATAL MERCURY Inventory of documents
No full textCOVERAGE 1949-1961Five photos: DF Malan, Genl JC Smuts, Dr HF Verwoer
STEENKAMP, Willem Petrus Inventory of documents
No full textCOVERAGE 1931-1946; 1 File; 0,11 Metre.Private papers of W.P. Steenkamp, MP Namakwaland [1929-1938], Calvinia [1938-1943]; Senator [1946-1948]
MULLER, Hilgard Inventory of documents
No full textCOVERAGE In Process; 7,60 Metres.
AUDIO CASSETTES IN ARCA COLLECTION = 7Private papers of H. Muller, National Party MP Pretoria East [1958-1961], Beaufort West [1964-1977], Minister of Foreign Affairs [1964-1977]
VON MOLTKE, Johannes von Strauss Inventory of documents
No full textCOVERAGE 1909-1971; 6 Files; 0,22 Metre.Private papers of J. von S. von Moltke, leader of the S.A. National Socialistic League [Greyshirts] in the Eastern Province [1934-1939]; National Party MP Karas SWA [1950-1966]
Alexin™-mediated defence responses in wheat during Russian wheat aphid (Diuraphis noxia) infestation
No full textThe Russian wheat aphid (RWA, Diuraphis noxia Kurdjumov) is a serious international pest occurring in wheat production areas in South Africa. The use of RWA-resistant cultivars is an effective pest management tactic, but the occurrence of resistance-breaking biotypes affects the durability of this strategy. We investigated the effect of Alexin™, a potential priming agent, on the defence responses of three different wheat cultivars challenged with two South African RWA biotypes-RWASA1 and RWASA2. Alexin™ (0.375%, v/v) pre-treatment selectively mediated the expression of resistance responses in the wheat cultivars. The resistance response was measured in terms of enzyme activities of β-1,3-glucanase and peroxidase. To compliment these findings three host plant resistance nodes (antixenosis, antibiosis and tolerance) were used to screen for Alexin™-mediated resistance. Alexin™ treatment mediated tolerance and antibiosis to RWASA1 and tolerance to RWASA2 in the cultivar SST387. These changes were evident as reduced intrinsic rate of aphid population and phenotypic damage rating score from susceptible to moderately resistant. Alexin™ treatment however, compromised the defence responses towards RWASA1 and RWASA2 in PAN3379, a cultivar with reported resistance to all four known South African biotypes. To understand the mechanisms of priming in resistance to RWA, we measured the levels of reactive oxygen species (H2O2), antioxidant enzyme activities and certain defence hormones, as well as, expression of some stress related genes. Alexin™ mediated accumulation of H2O2 in the susceptible cultivar, increase in antioxidant enzyme activities (CAT, GR, SOD) and levels of Salicylic acid (SA) relative to Jasmonic acid (JA). On the other hand, the treatment suppressed defence responses in the resistant cultivar, except the relatively high level of induced SA. We concluded that defence mechanisms might be induced with other defence signalling networks. Even though field studies were not repeatable due to extreme seasonal variations in rainfall and temperature, the results indicate that Alexin™ has a potential to express systemic acquired resistance in otherwise susceptible wheat cultivars, and as such can be incorporated into an integrated pest management system to improve aphid management in wheat.Nulandis (a division of AECI limited)National Research Foundation (NRF
WESSELS, JB Inventory of documents
No full textCOVERAGE: 0.01 metresSingle group photograph of Maree Kohler, Jannie Wessels, ADCJ Jacobsz, ADC Land, JHB Wessels, Comdt Louis Notha, Genl Wessels, Comdt FP Jacobsz, Comdt HJ Bruwer
DU PLESSIS, PG Inventory of documents
No full textPamphletsOrganiser of the VP in the Free State; Pamphlet