White men in Africa: Celati, Theroux, Kapuscinski

L’argomento principale dell’articolo è la posizione del turista bianco in viaggio attraverso l’Africa secondo un itinerario alternativo a quello consumistico. Si distingue dal turista con un itinerario prescelto, però la sua bianchezza è sempre un’etichetta ineluttabile che predispone i suoi rapporti con la gente e i luoghi visitati. L’alterità del continente offre un esilio temporaneo dall’Occidente, un distacco volontario, eppure il turista bianco rimane un estraneo, un distaccato collezionista di storie e impressioni

Exploring the Role of Environmental Quality and Time Perspective in the Academic Performance of Grade 12 Learners

The aim of this study was to determine to what extent environmental quality and time perspective can account for the variance in the academic performance of Grade 12 learners. Time perspective was assessed utilising the Zimbardo Time Perspective Inventory (ZTPI). Environmental quality was measured by means of a self-compiled questionnaire. A total of 413 Grade 12 learners from four English mediumschools in the Mangaung area of the Free State Province in South Africa were involved in the study. It was found that time perspective together with environmental quality accounts for approximately 14% of the variance found in the academic performance of Grade 12 learners. Although statistically significant relationships were found between time perspective and academic performance, these relationships were concluded to be of little practical importance. The academic performance of Grade 12 learners is of great importance as the results obtained from their final examinations are generally viewed as primary selection criteria for access to higher education institutions (Swartz, 1998; Uys, 1993; Huysamen, 2001). Various cognitive, personal and environmental factors have been found to influence learners’ academic performance (Moller, 1995; Louw, Van Ede & Louw, 1998; Malefo, 2000). Only a limited number of researchers have investigated the influence of environmental quality as well as time perspective on academic performance within the South African context. It is the aim of this study to explore the concepts of environmental quality and time perspective and their role in the academic performance of Grade 12 learners

Stability criteria for a pyramidal shaped asperity ploughing through a plastically deforming substrate

In two body abrasion processes hard asperities plough through a soft surface. If the asperities can resist the forces that act on it, scratches will develop in the soft material. If the asperities cannot withstand these forces, they will break off and not cause direct abrasion damage. The same is the case for galling, where lumps develop on one of the surfaces because of material transfer. These lumps will abrade the counter surface, if the lumps are strong enough to withstand the forces that act on it. In order to describe these phenomena, simple criteria are desired to describe the mechanical stability of asperities and lumps.\ud \ud In this work, an analytical model is presented for the mechanical stability of asperities. In the analysis, a pyramidal asperity shape will be assumed. Given the pyramidal asperity shape, several cases will be studied: the load is carried by a pyramid with a triangular base, a pyramid with a triangular base and an extended backside and the case where a crack has developed. Based on these models stability criteria of ploughing pyramidal asperities will be developed. Important results of the model will be discussed in the context of abrasion and adhesive wear processes

Knowledge, attitudes and practices of general practitioners in the Free State regarding the management of children with Attention Deficit Hyperactivity Disorder (ADHD)

The aim of this study,was to determine the knowledge, attitudes and practice of general practitioners (GP's) in the Free State regarding the management of children with Attention Deficit Hyperactivity Disorder (ADHD)