Leaderships Role In Effective Implementation Of School Discipline Policies

Discipline is an important aspect of the life of any school. Learning and teaching can only take place effectively in a disciplined environment. In South Africa, discipline policies might not have been effectively implemented due to inadequate sources, lack of commitment and training of school leaders. A qualitative research design was utilized for the investigation on which this article is based. The research consisted of two phases. First, group interviews were conducted with 27 B Ed Honours students; thereafter, individual interviews were conducted with a total of six students selected by purposive sampling. The results seem to suggest that the broader school community should be taken on board to ensure effective discipline policy implementation. The correct legal sources should furthermore be employed in the process of developing school policies. School leaders need thorough training for the development and implementation of discipline policies. Several measures are suggested for the effective introduction of disciplinary policies, among others, that school leadership should play a (more) active role; specifically the principals of schools should be willing to share their knowledge on the implementation of school disciplinary policies with other members of the school leadership

Transition to subcritical turbulence in a tokamak plasma

Tokamak turbulence, driven by the ion-temperature gradient and occurring in the presence of flow shear, is investigated by means of local, ion-scale, electrostatic gyrokinetic simulations (with both kinetic ions and electrons) of the conditions in the outer core of the Mega-Ampere Spherical Tokamak (MAST). A parameter scan in the local values of the ion-temperature gradient and flow shear is performed. It is demonstrated that the experimentally observed state is near the stability threshold and that this stability threshold is nonlinear: sheared turbulence is subcritical, i.e. the system is formally stable to small perturbations, but, given a large enough initial perturbation, it transitions to a turbulent state. A scenario for such a transition is proposed and supported by numerical results: close to threshold, the nonlinear saturated state and the associated anomalous heat transport are dominated by long-lived coherent structures, which drift across the domain, have finite amplitudes, but are not volume filling; as the system is taken away from the threshold into the more unstable regime, the number of these structures increases until they overlap and a more conventional chaotic state emerges. Whereas this appears to represent a new scenario for transition to turbulence in tokamak plasmas, it is reminiscent of the behaviour of other subcritically turbulent systems, e.g. pipe flows and Keplerian magnetorotational accretion flows.Comment: 16 pages, 5 figures, accepted to Journal of Plasma Physic

Symmetry breaking in MAST plasma turbulence due to toroidal flow shear

The flow shear associated with the differential toroidal rotation of tokamak plasmas breaks an underlying symmetry of the turbulent fluctuations imposed by the up-down symmetry of the magnetic equilibrium. Using experimental Beam-Emission-Spectroscopy (BES) measurements and gyrokinetic simulations, this symmetry breaking in ion-scale turbulence in MAST is shown to manifest itself as a tilt of the spatial correlation function and a finite skew in the distribution of the fluctuating density field. The tilt is a statistical expression of the "shearing" of the turbulent structures by the mean flow. The skewness of the distribution is related to the emergence of long-lived density structures in sheared, near-marginal plasma turbulence. The extent to which these effects are pronounced is argued (with the aid of the simulations) to depend on the distance from the nonlinear stability threshold. Away from the threshold, the symmetry is effectively restored

Ambulatory blood pressure monitoring - comparison with office blood pressure in patients on antihypertensive therapy in private practice

Introduction. Available data on the use of 24-hour ambulatory blood pressure recordings in private practice are limited. For this purpose we studied 39 consecutive hypertensive patients on treatment in a private practice.Method. Office blood pressure, 24-hour ambulatory blood pressure, daytime ambulatory blood pressure and M-mode echocardiography were undertaken in 39 consecutive hypertensive patients (21 men, 18 women) on treatment.Results. Mean 24-hour ambulatory blood pressure and mean daytime ambulatory blood pressure were lower than office blood pressure, similar to findings seen in academic settings. A blood pressure load of more than 50% was seen in 12 out of 39 patients (31 %). Left ventricular hypertrophy, assessed by means of Framingham criteria, was seen in 33% of patients. A white-coat effect was seen in 15.4% of patients.Conclusions. A large proportion (33%) of patients on treatment for hypertension had left ventricular hypertrophy, despite normal electrocardiograms. Ambulatory blood pressure measurements identified a blood pressure load of more than 50% in 31 % of patients on treatment for hypertension

Chenin blanc Wine Volatiles and the Intensity of a Guava-like Flavour

A guava-like flavour occurring in some South African Chenin blanc and Colombard dry white wines was investigated. Headspace volatiles of some of these wines, as well as those of fresh guava fruits, were analysed by means of a gas chromatograph equipped with a "sniffer-detector". In contrast to the headspace concentrate of guava fruits, no single fraction with a typical guava flavour was found in the wines analysed. The pattern recognition system "ARTHUR" was therefore used to investigate relationships between the more important wine volatiles and the intensity of a guava-like flavour of a set of wines originating from the same Chenin blanc must. Sensory scores for this flavour were used in both category and continuous property analysis in each case. Category and correlation to property plots were used to elucidate the results. Several promising variables and ratios between variables were singled out for further investigation, notably ethyl butyrate and the ratios ethyl butyrate/ethyl decanoate and ethyl butyrate/ethyl octanoate

Knowledge regarding basic concepts of hereditary cancers, and the available genetic counselling and testing services: A survey of general practitioners in Johannesburg, South Africa

Background. In families with hereditary cancer, at-risk individuals can benefit from genetic counselling and testing. General practitioners (GPs) are ideally placed to identify such families and refer them appropriately.Objective. To assess the practices, knowledge and attitudes of GPs regarding common hereditary cancers.Methods. An exploratory research design was used. An existing questionnaire was adapted, piloted and mailed to 196 GPs in Johannesburg, South Africa. The 61 GPs (31.1%) who completed and returned the questionnaire constituted the final sample. Data were analysed using descriptive statistics.Results. The GPs obtained some information on cancer family history from their patients, but not enough to assess the risks. Altogether 22 (36.1%) of the GPs referred patients to appropriate facilities for assessment and testing, while 32 (52.5%) were aware of genetic testing services. Most (38/61, 62.3%) were not familiar with the genetic counselling facilities available, but they felt patients should have counselling before testing. Less than half knew about possible paternal inheritance, or the low rate of hereditary mutations and their penetrance. Overall, the majority of GPs (53/61, 86.9%) were interested in learning more about cancer genetics and available services, and they expected to play an increasing role in the field in the future.Conclusions. Many of the GPs in this study had limited knowledge about inherited cancers, cancer risk management and genetic services. Appropriate education needs to be increased so that they are better equipped to identify and refer families at risk

Case Studies: Unusual phaeochromocytomas in African families: the importance of genetic testing

No AbstractKeywords: phaeochromocytomas; genetic testing; Von Hippel-Lindau syndrome; familial cancer; genetic counsellin

Ion-scale turbulence in MAST: anomalous transport, subcritical transitions, and comparison to BES measurements

We investigate the effect of varying the ion temperature gradient (ITG) and toroidal equilibrium scale sheared flow on ion-scale turbulence in the outer core of MAST by means of local gyrokinetic simulations. We show that nonlinear simulations reproduce the experimental ion heat flux and that the experimentally measured values of the ITG and the flow shear lie close to the turbulence threshold. We demonstrate that the system is subcritical in the presence of flow shear, i.e., the system is formally stable to small perturbations, but transitions to a turbulent state given a large enough initial perturbation. We propose that the transition to subcritical turbulence occurs via an intermediate state dominated by low number of coherent long-lived structures, close to threshold, which increase in number as the system is taken away from the threshold into the more strongly turbulent regime, until they fill the domain and a more conventional turbulence emerges. We show that the properties of turbulence are effectively functions of the distance to threshold, as quantified by the ion heat flux. We make quantitative comparisons of correlation lengths, times, and amplitudes between our simulations and experimental measurements using the MAST BES diagnostic. We find reasonable agreement of the correlation properties, most notably of the correlation time, for which significant discrepancies were found in previous numerical studies of MAST turbulence.Comment: 67 pages, 37 figures. Submitted to PPC

Some Volatile Aroma Components of Vitis Vinifera L. cv. Sauvignon blanc

Volatile aroma components of Vitis vinifera L. cv. Sauvignon blanc grapes were studied to identify the components responsible for the characteristic aroma of this grape cultivar. Thirty three volatile components were identified. Amongst these methional and trans-2, cis-6-nonadienal are reported present in Vitis for the first time. Evidence is also presented for the presence of three methoxypyrazines which are believed to be key substances responsible for the typical aroma present in grapes and wines of this cultivar

An audit of provincial gastroenterology services in the Western Cape

Background: While disorders such as gastro-oesophageal reflux disease, gastrointestinal (GI) cancers and inflammatory bowel disease are prevalent among all racial groups in the Western Cape, there is little knowledge of local GI service provision. The state of equipment, facilities and staffing is largely unrecorded and to date unknown. The aim of this study was to audit the availability of GI facilities in the provincial sector, which provides care for the majority of people in the Western Cape. Method: All hospitals in the Western Cape providing endoscopy were evaluated by means of a hands-on audit, to identify available organisational infrastructure. Data including staffing, details and utilisation of existing equipment, maintenance and disinfection techniques and delays in service provision were collected. Results: Over a period of 12 months, 17 Western Cape hospitals were visited : 3 tertiary, 5 regional and 9 district-level institutions. There are currently 89 GI endoscopes in state service, with an average age of 6.1 years (range 1 - 23 years). While most institutions utilise video endoscopy, in many instances equipment is near the end of its economic life. A total of 26 434 endoscopic procedures were performed over a 12-month period. Overall at least 60% of all adult endoscopy was undertaken at tertiary institutions. The mean delay from consultation until gastroscopy or colonoscopy was 9.25 weeks (range 0.5 - 28 weeks) and 8 weeks (range 1 - 20 weeks), respectively. Only 1 tertiary and 1 regional hospital employed fully trained, registered nurses, and the majority of institutions did not conform to internationally accepted standards for the maintenance and disinfection of endoscopic equipment. Conclusion: While endoscopy equipment is widely distributed throughout the province, it is evident from this study that services in the Western Cape fall short of international standards, with delays in endoscopic provision, lack of adequate equipment, inadequate scope maintenance and disinfection and a shortage of trained staff. As such, much of the population reliant on state facilities has poor access to GI health care. These deficiencies need to be addressed