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The Place And Role Of Em-learning In Multi-mode Delivery Of Educator Training In South Africa

In any country in the world, the business and responsibility of, as well as the challenge to the education fraternity are to provide quality education to all. Therefore, quality teaching and learning should be provided to assist all learners to acquire the required competencies (knowledge, skills and attitudes) at the highest possible level in order to fulfil their respective and diverse roles in life (Steyn, Steyn, De Waal and Wolhuter, 2002: 34). The point of departure should be to provide quality education in such a way that it is accessible and affordable to all. The quality of education is to a large extent determined by the quality of information transfer and the quality and quantity of support that the learners receive to master the outcomes of their studies. The developments in the field of Information and Communication Technology (ICT) provide a real opportunity to improve the quality of information transfer and teaching support that learners can obtain. However, the real challenge for education in the developing world, and even in the developed world, is the level of accessibility, affordability and complexities of ICT (Dreyer, 2005: 4). The result of the ability to provide assessable ICT in developing countries is the ever-increasing digital gap that deeply influences the quality of education of less affluent people and the difference in quality of education between developed and developing countries. At the North-West University, Faculty of Education Sciences, the decision was made to provide enriched teaching and learning to a particular group of teachers via an off-campus blended teaching and learning strategy. Within the limitations of affordability and access, the decision was made to use the multi-mode teaching strategy (including some types of modern ICT) to support the students and to enhance the support that the learners obtain. The aim of this article is to report on the reasons, development and implementation of the project as well as initial results. Attention will be given to the nature and contents of the ADP-programme, the theoretical framework that was used to develop the strategy and the nature and content of the multi-mode teaching strategy that was employed. The method of research that was used to develop the teaching and learning strategy particularly applicable to this programme was that of a process of iterative and systematic critical reasoning. Based on the critical reasoning, it was through an combined (and not necessarily initially decided upon) application of several (applicable) scientific methods and processes, such as observation, analysis and synthesis, induction and deduction that the strategy was developed (Stoker, 1961: 62-90; Mouton and Marais, 1989: 102; Mouton, 1996; 77-78; Harden and Thomas, 2005: 258; Bensley, 1998: 3; Ennis, 1987: 9).Faculty of Education Sciences North-West Universit

Partial purification and properties of thiaminokinase from yeast

Thiaminokinase, the enzyme catalyzing the synthesis of thiaminepyrophosphate from thiamine and adenosinetriphosphate, has been extracted from fresh bakers' yeast by plasmolysis by freezing at -70°C and thawing, followed by maceration at 37° in 0.5 M KCl. The enzyme has been partially purified by fractionation of the yeast extract with ammonium sulphate. The active protein fraction has been subjected to fractional analysis according to . It is pointed out that the protein leaving the solution in the same range of salt concentration as does the enzymic activity is not homogeneous and probably does not represent the enzyme protein, but inert proteins which have adsorbed the enzyme - which will only constitute a small fraction of the precipitating protein - to the same extent. Thiaminokinase requires Mg for its action. Optimal activation is obtained with concentrations of 2·10-2 M. Low concentrations of Mn also activate the enzyme, even more so than comparable amounts of Mg; but concentrations of Mn above 2·10-3 M markedly inhibit the phosphorylation of thiamine. The action of the enzyme is stimulated strongly by small amounts of inorganic phosphate. Maximal effect is obtained with a concentration of 2·10-3 M. The crude yeast extract contains at least two factors inhibiting thiaminokinase, which can be removed by dialysis, and are thermostable. One of these is of inorganic nature. The enzyme deploys its maximal activity in the pH range of 6 to 8. The purified preparation synthesizes thiaminepyrophosphate at a higher rate from thiamine than from thiamine monophosphate

Connexin36 knockout mice display increased sensitivity to pentylenetetrazol-induced seizure-like behaviors

Large-scale synchronous firing of neurons during seizures is modulated by electrotonic coupling between neurons via gap junctions. To explore roles for connexin36 (Cx36) gap junctions in seizures, we examined the seizure threshold of connexin36 knockout (Cx36KO) mice using a pentylenetetrazol (PTZ) model

Mid-trimester termination ofpregnancy - a randomised controlled trial of two prostaglandin regitnens

Objective. To detennine the more applicable of two ways of prostaglandin induction currently in use in second trimester induced abortions for congenital or chromosomal abnormalities.Design. A prospective randomised controlled trial.Setting. Department of Obstetrics and Gynaecology, Tygerberg Hospital, CP.Study population. Twenty consecutive patients admitted for tennination of pregnancy for congenital or chromosomal abnormalities between 14 and 26 weeks' pregnancy duration. Management. Patients were randomly selected to receive either 1,5 mg prostaglandin E, (PGE,) gel extra-amniotically or 25 mg prostaglandin F,a (PGF,a) intra-amniotically. Patients in both groups received oxytocin to a maximum dosage of 120 IllU per minute if they had not aborted 18 hours after the original administration of either prostaglandin regimen. If abortion had not taken place 36 hours after cotnmencement of treatment, management was considered unsuccessful.Main outcome measurements. Proportion of successful inductions and complications.Results. Complications of management were rare and did not differ between the two management groups. However, there were significantly more failures in the group who receh'ed intraamniotic PGF,a (7 v. 2 patients) as well as a significantly higher need for oxytocin in this group (10 v. 4 patients).Conclusions. With· proIllising drugs such as prostaglandin analogues and anti-progesterones not universally available, methods of induction suitable to the local situation should be sought. Extra-atnniotic PGE, seems more suitable than intra-amniotic PGF,a because of a shorter induction- to-delivery time without increased morbidity

Potential of South African entomopathogenic nematodes to control the leaf miner, Holocacista capensis (Lepidoptera: Heliozelidae)

The Cape grapevine leafminer, Holocacista capensis, a sporadic pest of economic importance, is found in South African table and wine grape vineyards. The cocoon casings, constructed by the final instar larvae, can be found attached to grape bunches, posing a phytosanitary risk for table grape export markets. The current study aimed to determine the susceptibility of leaf-mining H. capensis larvae toseven entomopathogenic nematode (EPN) species belonging to Steinernematidae and Heterorhabditidae.  To determine nematode virulence occupied leaf-mining galleries were extracted from infested leaves and inoculated with 200 infective juveniles (IJs) in 50 μl of distilled water, for each of the EPNs screened.Concentration assays were conducted and and lethal dose was determined for the three most virulent species (Heterorhabditis baujardi, H. indica and H. noenieputensis), using concentrations of 0, 25, 50, 100, 200, and 400 IJs/leaf-mining larva. High mortality of leaf-mining larvae was obtained with H. baujardi(92%), H. noenieputensis (85%) and H. indica (83%). Almost double the number of H. noenieputensis (34 nematodes/insect) penetrated the insect larvae, in comparison with the other two EPNs. However, the relative potency of H. baujardi was 3.56 times higher than for H. indica, whilst that of H. indica was 2.57times higher than it was for H. noenieputensis. The results obtained in the laboratory were found to be encouraging, especially with regard to the nematodes’ ability to penetrate the leaf-mining galleries, and to infect the larvae successfully

A Review of Leaf-mining Insects and Control Options for their Management, with Special Reference to Holocacista capensis (Lepidoptera: Heliozelidae) in Vineyards in South Africa

A leaf-mining pest occurring on commercial varieties of Vitis vinifera in South Africa was investigated due to the presence of cocoons on fruit. The leaf miner, Holocacista capensis, was reported on grapevines in 2012. Since its discovery on commercial grape varieties, control strategies have consisted solely of insecticide applications. Despite the fact that the leaf-mining habit is taxonomically diverse and considered ancient, little is generally known of leaf-mining larvae. A review was conducted in order to better understand the leaf-mining strategy and amalgamate the current knowledge of other leaf-mining insects.  The general evolutionary history within the full complement of taxa that display the leaf-mining habit is discussed. The review focuses on lepidopteran leaf-mining pests and discloses the known information associated with the first report and the impact of H. capensis in the Western Cape, South Africa. As no control methods have been identified for H. capensis in vineyards, various chemical, biological and cultural control strategies adopted for other leaf-mining pests were investigated. Control options, including theuse of entomopathogenic nematodes (EPNs), parasitoids, physical and cultural control measures, were considered and are discussed. Alternate control methods are pertinent for the grape-growing industry to avoid the development of the insecticide resistance that is common amongst leaf miners. This review aims to consolidate the available literature and therefore aid in the development of an integrated pest management strategy to effectively control H. capensis in infested vineyards in South Africa

Can the high prevalence of micronutrient deficiencies, stunting and overweight in children at ages 1 and 3 years in the Central Region of Limpopo province be explained by diet?

Objective. To assess whether the high prevalence of stunting and overweight accompanied by serum deficiencies of iron, folate and vitamin B12 in children at ages 1 and 3 years, can be explained by their diet. Design. A prospective cohort study. Setting. Villages in the central region of Limpopo province, which are serviced by Mankweng Hospital. Subjects. A cohort of children (N = 219) followed from birth were included in the study. Of the original cohort, 156 and 162 could be traced and assessed at ages 1 and 3 years, respectively. Dietary intake of the children was assessed using a quantitative food frequency questionnaire and at 3 years a 24-hour recall questionnaire was also administered. Results. The children in this cohort consumed an energy-dense diet of poor quality as evidenced by insufficient intakes of iron, zinc, calcium and phosphates as well as folate, riboflavin, vitamin B6, niacin and vitamin A. Overall, nearly 70% of the energy intake of the diet came from carbohydrates while the contribution from fat was less than 20%. Average protein intake was adequate but comprised mainly protein from vegetable sources which are poor sources of iron and certain essential amino acids. Furthermore, the diet was judged to be high in phytates because of the high intake of cereals and this would have contributed to making iron and zinc less available for absorption. Low fruit and vegetable intake was the cause of the low intake of folate, vitamin A and vitamin C. The prevalence of micronutrient deficiencies was confirmed by the high prevalence of children with iron and folate biochemical deficiencies. Conclusion. The children's diet was poor in several micronutrients which included iron, calcium, folate and vitamin A. Chronic energy deficiency, especially from animal sources, seems to be the factor contributing to the high levels of stunting observed. South African Journal of Clinical Nutrition Vol. 19(3) 2006: 102-11