'n Internasionale perspektief op leerderdissipline in skole

An international perspective on learner discipline in schools. Experience with disciplinary problems among learners in schools in three highly developed countries (USA, Great Britain, and Australia) has shown that disciplinary problems are not unique to certain countries and, generally speaking, they can and should be managed by means of pedagogical interventions. Also the solution to learners' disciplinary problems in South African schools does not appear to lie in an emulation of the theories and practices in developed countries. These countries themselves suffer from too many internal structural problems. A possible solution for disciplinary problems in South Africa lies in a correction of this country's social-structural problems, especially those leading to poverty or exorbitant wealth. Once such problems have been eradicated, learners will feel better about themselves and their situation. This in turn may lead to a decrease in anti-social behaviour. South African Journal of Education Vol.23(3) 2003: 225-23

Genetic Association Study of Common Mitochondrial Variants on Body Fat Mass

Mitochondria play a central role in ATP production and energy metabolism. Previous studies suggest that common variants in mtDNA are associated with several common complex diseases, including obesity. To test the hypothesis that common mtDNA variants influence obesity-related phenotypes, including BMI and body fat mass, we genotyped a total of 445 mtSNPs across the whole mitochondrial genome in a large sample of 2,286 unrelated Caucasian subjects. 72 of these 445 mtSNPs passed quality control criteria, and were used for subsequent analyses. We also classified all subjects into nine common European haplogroups. Association analyses were conducted for both BMI and body fat mass with single mtSNPs and mtDNA haplogroups. Two mtSNPs, mt4823 and mt8873 were detected to be significantly associated with body fat mass, with adjusted P values of 4.94×10-3 and 4.58×10-2, respectively. The minor alleles mt4823 C and mt8873 A were associated with reduced fat mass values and the effect size (β) was estimated to be 3.52 and 3.18, respectively. These two mtSNPs also achieved nominally significant levels for association with BMI. For haplogroup analyses, we found that haplogroup X was strongly associated with both BMI (adjusted P = 8.31×10-3) and body fat mass (adjusted P = 5.67×10-4) Subjects classified as haplogroup X had lower BMI and fat mass values, with the β estimated to be 2.86 and 6.03, respectively. Our findings suggest that common variants in mitochondria might play a role in variations of body fat mass. Further molecular and functional studies will be needed to clarify the potential mechanism

Mitochondrial ATP synthase: architecture, function and pathology

Human mitochondrial (mt) ATP synthase, or complex V consists of two functional domains: F1, situated in the mitochondrial matrix, and Fo, located in the inner mitochondrial membrane. Complex V uses the energy created by the proton electrochemical gradient to phosphorylate ADP to ATP. This review covers the architecture, function and assembly of complex V. The role of complex V di-and oligomerization and its relation with mitochondrial morphology is discussed. Finally, pathology related to complex V deficiency and current therapeutic strategies are highlighted. Despite the huge progress in this research field over the past decades, questions remain to be answered regarding the structure of subunits, the function of the rotary nanomotor at a molecular level, and the human complex V assembly process. The elucidation of more nuclear genetic defects will guide physio(patho)logical studies, paving the way for future therapeutic interventions

Development of an air quality management framework for municipal government

Air quality problems have been an inescapable partner of global economic development, and such problems have prevailed since the industrial age. After the democratisation of South Africa in 1994, the government embarked on a law reforming process to bring all the laws of the country in line with the new constitution of South Africa. This process included air quality legislation. Air quality management in South Africa has undergone drastic changes with the implementation of the National Environmental: Air Quality Act (Act 39 of 2004). In the previous dispensation, the Air Pollution Prevention Act (1965), emphasised point-source control, but the new act shifted the emphasis from point-source control to reactively protecting the receiving environment. In keeping with the new approach, municipalities are now required to compile, implement and maintain air quality management plans. Although, this is an explicit requirement of the Act, no guidelines exist for regulating bodies regarding the content of such plans. In this paper, a framework for generic air quality management plans for municipalities is proposed. This framework was compiled using information gained during a literature study of two countries where the implementation of air quality management plans has brought about an improvement in air quality, as well as two other countries where despite implementation of such plans, air quality has deteriorated. The information gained from the literature study was used to compile questionnaires that were distributed to all metropolitan councils and district municipalities (N = 54) in South Africa. To obtain a comprehensive, contextualised view on the issue, industries (N = 1 290) were also included in the study. The main contribution of this study was the compilation of a framework for a generic air quality management plan to be used by municipal authorities. Due to the fact that lack of training has been identified as a critical gap in the successful implementation and maintenance of an air quality management plan, this study also makes a significant contribution to the identification of generic training outcomes.Key words: Air quality management plans, air quality, municipality, local authorities, local government, framework, training outcomes