Exploring a secondary school educator’s experiences of school violence: a case study

In an increasingly violent society, South African secondary school educators often need to manage violent learners. In the context of a challenging and uniquely South African educational environment, managing this escalating violence often leaves educators battling to cope with increasing demands for learner performance in the midst of an inherited culture of violence and intimidation that spills over into the classroom. We attempt to explore, from an interpretive perspective, the experiences of an educator in a violence-affected educational setting. This includes the educator’s perceptions of the causes, nature and results of violence. The article also unveils the educator's emotional experience and her perceptions of what contributes to the violence.Keywords: bio-ecological systems theory; educator; learners; violence/school violenc

The Effect of Juice Clarity and Several Conditions Promoting Yeast Growth on Fermentation Rate, the Production of Aroma Components and Wine Quality

In cellar practice grape juice is preferably made as clear as possible, and fermentations take place under strictly anaerobic conditions. In the laboratory, however, the fermentation rate of EK-filtered and de-aerated juices was always so much slower than that of juices obtained by normal cellar routine that no dry wines could be prepared unless fermentation stimulating methods were applied. Apparently in most cellar fermentations sufficient amounts of oxygen and/or of yeast growth promoting steroids from the grapes are present to complete fermentation, but the exact amounts present are unknown. In practice problems with lagging fermentation could occur in cases where clarifying and de-aeration of juice were performed too rigorously. Grape juice was clarified by diverse methods, and white wines were prepared from the juices under various conditions in order to study the effect of de·aeration, addition of settled juice with residual turbidity, micro-aeration and application of ergosterol suspensions on fermentation rate. EK-filtered juices were used to experiment with methods for reactivating lagging fermentation and also forinvestigating the effect of fermentation conditions on the production of wine volatiles. With the aid of the above-mentioned fermentation stimulating means the fermentation of EK-filtered juices could be completed within an acceptable period of time. Steps to reactivate lagging fermentations should be taken as early as possible, although additions of settled juice were often successful, even when applied at a late stage during fermentation. Filtered juice from different cultivars and origins behaved in a markedly similar way with regard to fermentation and the production of volatile components. Filtration of juice caused partial loss of the cultivar character of the wine but wines from filtered juice with additions of ergosterol were nevertheless allotted the highest scores during organoleptic evaluation. The production of higher alcohols depends on the degree of juice turbidity and fermentation temperature. In clear filtered juice, however, the production of higher alcohols was independent of fermentation temperature. The formation of acetates of higher alcohols is greatly enhanced, by adding ergosterol to the filtered juice

Will working students flourish or give up? Exploring the influence of academic psychological capital, grit, and time management

Working students are faced with challenges and responsibilities both at university and in their employment. In attempting to study the books and chapters assigned, meet assignment deadlines, participate in extracurricular activities, and functions at work, working students may be overwhelmed. The primary aim of this study was to examine and understand the influence of non-cognitive factors (including Psychological Capital, time management, and grit) on flourishing and the working student’s intention to quit their studies. A non-probability sampling technique indicating convenience sampling and purposive sampling were employed to recruit respondents. The sample (n = 194) was from a residential university in the Western Cape of South Africa. Non-cognitive variables had a positive relationship with flourishing and a negative relationship with intention-to-quit studies. Academic mindset measured as Psychological Capital explained the largest proportion of the variance in flourishing and intention-to-quit studies. Lecturers, counsellors, and university officials should collaborate to incorporate programmes that will aid in developing these non-cognitive variables into the university’s curriculum. These interventions may help improve academic success and throughput of working students

Complete moduli of cubic threefolds and their intermediate Jacobians

The intermediate Jacobian map, which associates to a smooth cubic threefold its intermediate Jacobian, does not extend to the GIT compactification of the space of cubic threefolds, not even as a map to the Satake compactification of the moduli space of principally polarized abelian fivefolds. A much better "wonderful" compactification of the space of cubic threefolds was constructed by the first and fourth authors --- it has a modular interpretation, and divisorial normal crossing boundary. We prove that the intermediate Jacobian map extends to a morphism from the wonderful compactification to the second Voronoi toroidal compactification of the moduli of principally polarized abelian fivefolds --- the first and fourth author previously showed that it extends to the Satake compactification. Since the second Voronoi compactification has a modular interpretation, our extended intermediate Jacobian map encodes all of the geometric information about the degenerations of intermediate Jacobians, and allows for the study of the geometry of cubic threefolds via degeneration techniques. As one application we give a complete classification of all degenerations of intermediate Jacobians of cubic threefolds of torus rank 1 and 2.Comment: 56 pages; v2: multiple updates and clarification in response to detailed referee's comment

Factors affecting the reproducibility of fermentation of grape juice and of the aroma composition of wines 1. Grape maturity, sugar, inoculum concentration, aeration, juice turbidity and ergosterol

Gas chromatographic analysis was used for the investigation of some factors which determine the production of volatile wine components during fermentation. Especially the effect of "heterogenous" juice factors such as turbidity and air content were investigated in respect of fermentation rate and the production of fatty acids, fusel alcohols and esters. lt was shown that the fermentation lag of clear filtered and de-aerated grape juices could be prevented by small ergosterol additions before inoculation. A marked similarity was observed in the chromatograms of wines from fermentations of clear juices which were stimulated either by air or by ergosterol. Grape maturity proved to be a major factor affecting the production of volatile acids, alcohols and esters during fermentation. Fermentations of de-aerated and clear filtered juice with an addition of 0.5 g bentonite/l yielded wines with the best scores an sensory evaluation.Maßgebliche Faktoren für die Reproduzierbarkeit der Vergärung von Traubenmostund die Aromazusammensetzung von WeinI. Traubenreife, Zucker, Konzentration des lnokulums, Luft, Klarheit des Mostesund ErgosterinEinige Faktoren, welche die Bildung flüchtiger Weininhaltsstoffe bei der Gärung beeinflussen, wurden gaschromatographisch untersucht. Besonders die Wirkung „heterogener" Faktoren im Traubenmost, wie zum Beispiel Trübung und Luftgehalt, auf die Gärungsgeschwindigkeit und die Bildung von Fettsäuren, Fuselalkoholen und Estern wurde untersucht. Es wurde gezeigt, daß die Gärungsverzögerung bei klarfiltrierten und entlüfteten Traubensäften durch die Zufügung kleiner Mengen von Ergosterin vor der Inokulation verhindert werden kann. Wurde die Gärung von geklärtem Most durch Luft oder durch Ergosterin angeregt, so zeigten die Chromatogramme der Weine eine starke Ähnlichkeit. Die Traubenreife erwies sich als der wichtigste Faktor, der die Bildung von flüchtigen Säuren, Alkoholen und Estern bei der Gärung beeinflußt. Die Vergärung von entlüftetem und klarfiltriertem Most mit Zusatz von 0,5 g Bentonit/l ergab Weine, die bei der Weinprobe die höchsten Punktezahlen erhielten

Preliminary investigation into the cause of acid mine water induced seismicity in Johannesburg

A preliminary investigation was done into the possible causes of the increased seismic activity in the Witwatersrand Basin. The paper focuses on approximated underground mining areas, groundwater mobility, rock types and the proximity of fault lines to seismic events. These parameters were mapped and correlated with observed seismicity in the area. There is some indication that the presence of underground mining areas has a positive relationship with the occurrence of seismic events. The other parameters exhibit a negative relationship with seismic activity. However, more detailed investigations are required before final conclusions can be drawn. An approach to risk assessment of possible earthquake scenarios in the City of Johannesburg (CoJ) is proposed. The approach aims to assess potential damage to infrastructure and loss of life in the case of an earthquake. The results of such an assessment may provide justification for more detailed investigations

Composition analysis of nickel silicide formed from evaporated and sputtered nickel for microsystem devices

Nickel silicide (NiSi) is highly suitable for microsystem fabrication, exhibiting suitable mechanical properties and good resistance to bulk micromachining etchants. Conditions for the formation of nickel silicide by vacuum annealing thin films of nickel deposited on silicon substrates are investigated. Nickel silicide thin films formed using sputtered and evaporated nickel films were analysed using Auger electron spectroscopy, which has shown that evaporated thin films of nickel tend to form nickel silicide more readily and with less thermal effort

Evaluation of the use of low-molecular-weight heparin for venous thromboembolism prophylaxis in medical patients

Background. Venous thromboembolism (VTE) complicates a significant proportion of medical admissions. As well as increasing patient morbidity, pulmonary embolism is one of the commonest preventable causes of in-hospital death. An increase in the use of pharmacological preventive measures has been advocated in recent years. South African (SA) and international guidelines have been published in an effort to promote the safe use of VTE prophylaxis.Objectives. To describe adherence to both local and international recommendations for VTE prophylaxis in an SA hospital with regard to appropriateness of the decision to prescribe or withhold low-molecular-weight heparin (LMWH), and to observe the practice of dose adjustment in special population groups.Methods. This was a prospective, observational study, and data were collected from consenting adults admitted to the medical wards. We assessed the patients’ VTE risk, bleeding risk and the presence of contraindications at the time of LMWH prescription as well as the dose prescribed, specifically taking into consideration adjustment for renal dysfunction and obesity.Results. Three hundred and fifty-two patients were enrolled, of whom 51.4% were male and 58.5% received LMWH. Primary outcomes. The appropriate overall decision according to both SA and international guidelines was made in 254 cases (72.2%). The inappropriate decision according to both guidelines was made in 79 cases (22.4%) and the appropriate decision according to one guideline only was made in 18 cases (5.1%), while 1 case (0.3%) was not categorised. Contraindications to VTE prophylaxis were present in 35 patients (9.9%), but 9 of these patients nevertheless received LMWH. An incorrect dose was prescribed in 36 cases (17.5%), the most common reason being an inappropriate reduction in the dose in mild renal dysfunction. Secondary outcomes. Other medications that may have increased bleeding risk were prescribed in 46 patients who received LMWH (22.3%). Mechanical prophylaxis was indicated in 25 (7.1%) of the total sample; however, none received this.Conclusions. Overall adherence to published guidelines for VTE prophylaxis has improved compared with other published reviews on the topic, but documentation of patients’ VTE risk in files is poor. Overuse in low-risk patients may be an unintended consequence of the widespread advocacy of LMWH use in hospital, highlighting the importance of adequate VTE risk stratification. Incorrect dosing in special population groups is an issue that needs to be addressed, as is non-utilisation of mechanical prophylaxis methods.

Stirring of sea ice meltwater enhances submesoscale fronts in the Southern Ocean

In the sea ice-impacted Southern Ocean, the spring melt of sea ice modifies the upper ocean. These modified waters subduct and enter the global overturning circulation. Submesoscale processes act to modulate the stratification of the mixed layer and therefore mixed layer properties. Sparse observations mean that the role of submesoscales in exchange across the base of the mixed layer in this region is not well constrained. The goal of this study is to determine the interplay between sea ice melt, surface boundary layer forcing, and submesoscale flows in regulating the mixed layer structure in the Antarctic Marginal Ice Zone. High-resolution observations suggest that fine-scale lateral fronts, representative of submesoscale mixed layer eddies (MLEs), arise from mesoscale gradients produced by northwards advecting sea ice meltwater. The strong salinity-driven stratification at the base of the mixed layer confined the MLEs to the upper ocean, limiting submesoscale vertical fluxes across the mixed layer base. This strong stratification prevents the local subduction by submesoscale flow of these modified waters, suggesting that the subduction site that links to the global overturning circulation does not correspond with the location of sea ice melt. However, the presence of MLEs enhanced the magnitude of lateral gradients through stirring and increased the potential for Ekman-driven cross-frontal flow to modulate the stability of the mixed layer and mixed layer properties. The inclusion, particularly of submesoscale Ekman Buoyancy Flux parameterizations, in coupled-climate models, may improve the representation of mixed layer heat and freshwater transport in the ice-impacted Southern Ocean during summer

Stirring of Sea‐Ice Meltwater Enhances Submesoscale Fronts in the Southern Ocean

In the sea‐ice‐impacted Southern Ocean, the spring sea‐ice melt and its impact on physical processes set the rate of surface water mass modification. These modified waters will eventually subduct near the polar front and enter the global overturning circulation. Submesoscale processes modulate the stratification of the mixed layer (ML) and ML properties. Sparse observations in polar regions mean that the role of submesoscale motions in the exchange of properties across the base of the ML is not well understood. The goal of this study is to determine the interplay between sea‐ice melt, surface boundary layer forcing, and submesoscale flows in setting properties of the surface ML in the Antarctic marginal ice zone. High‐resolution observations suggest that fine‐scale lateral fronts arise from either/both mesoscale and submesoscale stirring of sea‐ice meltwater anomalies. The strong salinity‐driven stratification at the base of the ML confines these fronts to the upper ocean, limiting submesoscale vertical fluxes across the ML base. This strong stratification prevents the local subduction of modified waters by submesoscale flows, suggesting that the subduction site that links to the global overturning circulation does not correspond with the location of sea‐ice melt. However, surface‐enhanced fronts increase the potential for Ekman‐driven cross‐frontal flow to modulate the stability of the ML and ML properties. The parameterization of submesoscale processes in coupled‐climate models, particularly those contributing to the Ekman buoyancy flux, may improve the representation of ML heat and freshwater transport in the ice‐impacted Southern Ocean during summer