Die F.A.K. en die toekoms

Waar die Federasie van Afrikaanse Kultuurvereniginge (FAK) vanjaar sy veertigste bestaansjaar gedenk, is dit seker gepas om hierdie beskeie toekomsblik te bind aan ’n rigtingbepalende terugblik. In die notule van die Uniale Taal- en Kultuurkonferensie wat op 18 en 19 Desember 1929 in Bloemfontein gehou is, lees ons: „Geesdriftige kultuurstryders hou krygsraad, krygsraad vir meer stelselmatige strydvoering… Leemetfordskote en konsentrasiekampe om die nasie te oorbluf

Die Middeleeuse Opvattinge oor Rente en Handel.

Dit is opmerklik hoe baie bedryfsekonomiese geskrifte sedert die 20 eeu die aandag vestig op die nuwe houding wat deur die ondernemer teenoor die verskillende elemente in sy onderneming ingcneem hehoortte word, nie alleen teenoor die ekoriomies-tegniese nie, maar veral ook teenoor die menslike element

Die monopolievorming in die diamantontginningsnywerheid van Suid-Afrika

Die diamantontginningsnywerheid is een van Suid-Afrika se oudste mynbouvertakkinge. Sedert die eerste diamant in 1867 aan die suidelike oewer van die Oranjerivier in die distrik Hopetown ontdek is, het ’n tydperk van ongeveer 91 jaar verloop, en gedurende hierdie tydperk het die diamantnywerheid baie veranderinge ondergaan

Burden of fetal alcohol syndrome in a rural West Coast area of South Africa

Background. Fetal alcohol syndrome (FAS) is common in parts of South Africa; rural residence is a frequently cited risk factor. We conducted a FAS school prevalence survey of an isolated rural community in a West Coast village of Western Cape Province, so obtaining the first directly measured rate, focusing specifically on a South African rural area, of FAS and partial FAS (PFAS). Methods. The study area (Aurora village), a community of about 2 500 people in a grain-producing region, has one primary school. All learners were eligible for study inclusion. Initial anthropometry screening was followed by a diagnostic stage entailing examination by a dysmorphologist for features of FAS, neurodevelopmental assessment, and an interview assessing maternal alcohol consumption. Results. Of 160 learners screened, 78 (49%) were screen-positive, of whom 63 (81%) were clinically assessed for FAS. The overall FAS/PFAS rate among the screened learners was 17.5% (95% confidence interval 12.0 - 24.2%), with 16 (10.0%) children having FAS and 12 (7.5%) PFAS. High rates of stunting, underweight and microcephaly were noted in all learners, especially those with FAS or PFAS. Five (18%) mothers of affected children were deceased by the time of assessment. Conclusion. We describe very high rates of FAS/PFAS in an isolated rural part of the Western Cape that is not located in a viticultural region. Our study suggests that the prevalence of FA S may be very high in isolated communities, or in particular hot-spots. It adds to the growing evidence that FAS/PFAS is a significant, and underestimated, health problem in South Africa. Expanded screening and surveillance programmes, and preventive interventions, are urgently needed

Duchenne and Becker muscular dystrophy prevalence in South Africa and molecular findings in 128 persons affected

A genetic service for Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) was initiated in Cape Town in 1987. Of the 143 DMD patients diagnosed during the period 1987-1992, 66 had a familial pattern of inheritance and 77 were apparently sporadic. Twenty BMD patients were identified, of whom 12 had other affected relatives and 8 were sporadic. Overall minimum prevalence rates of 1/100 000 for DMD and 1/55 000 for BMD were calculated. A markedly low DMD prevalence in the indigenous black population (1/250000) contributed tothe overall low DMD prevalence in South Africa when compared with that in the UK (1/40 000).By means of molecular methods, the diagnosis in 42% of the affected DMD males was confirmed by detection of deletions in the dystrophin gene. Deletions were identified in 50% of Indian, white and mixed ancestry patients. In contrast, only 22% of blacks had identifiable deletions.DMD appears to be underrepresented in the black population; the low deletion frequency in this group suggests that unique mutations not detectable by methods used in this study may be more frequent in these patients than in the other populations. The increased DMD frequency in Indians corroborates findings reported from the UK

Solitary waves and supersonic reaction front in metastable solids

Motivated by an increasing number of remarkable experimental observations on the role of pressure and shear stress in solid reactions, explosions and detonations, we present a simple toy model that embodies nonlinear elasticity and dispersion as well as chemical or phase transformation. This generalization of the Toda Lattice provides an effective model for the description of the organization during an abrupt transformation in a solid. One of the challenges is to capture both the equilibrium degrees of freedom as well as to quantify the possible role of out-of-equilibrium perturbations. In the Toda Lattice, we verify that the particle velocities converge in distribution towards the Maxwell-Boltzmann distribution, thus allowing us to define a bona-fide temperature. In addition, the balance between nonlinearity and wave dispersion may create solitary waves that act as energy traps. In the presence of reactive chemistry, we show that the trapping of the released chemical energy in solitary waves that are excited by an initial perturbation provides a positive feedback that enhances the reaction rate and leads to supersonic explosion front propagation. These modes of rupture observed in our model may provide a first-order description of ultrafast reactions of heterogeneous mixtures under mechanical loading

Theoretically proposed optimal frequency for ultrasound induced cartilage restoration

Background: Matching the frequency of the driving force to that of the system’s natural frequency of vibration results in greater amplitude response. Thus we hypothesize that applying ultrasound at the chondrocyte’s resonant frequency will result in greater deformation than applying similar ultrasound power at a frequency outside of the resonant bandwidth. Based on this resonant hypothesis, our group previously confirmed theoretically and experimentally that ultrasound stimulation of suspended chondrocytes at resonance (5 MHz) maximized gene expression of load inducible genes. However, this study was based on suspended chondrocytes. The resonant frequency of a chondrocyte does not only depend on the cell mass and intracellular stiffness, but also on the mechanical properties of the surrounding medium. An in vivo chondrocyte’s environment differs whether it be a blood clot (following microfracture), a hydrogel or the pericellular and extracellular matrices of the natural cartilage. All have distinct structures and compositions leading to different resonant frequencies. In this study, we present two theoretical models, the first model to understand the effects of the resonant frequency on the cellular deformation and the second to identify the optimal frequency range for clinical applications of ultrasound to enhance cartilage restoration. Results: We showed that applying low-intensity ultrasound at the resonant frequency induced deformation equivalent to that experimentally calculated in previous studies at higher intensities and a 1 MHz frequency. Additionally, the resonant frequency of an in vivo chondrocyte in healthy conditions, osteoarthritic conditions, embedded in a blood clot and embedded in fibrin ranges from 3.5 − 4.8 MHz. Conclusion: The main finding of this study is the theoretically proposed optimal frequency for clinical applications of therapeutic ultrasound induced cartilage restoration is 3.5 − 4.8 MHz (the resonant frequencies of in vivo chondrocytes). Application of ultrasound in this frequency range will maximize desired bioeffects

Researching the first year accounting problem : factors influencing success or failure at a South African higher education institutions

Published ArticleUnder-performance and failure in first year accounting is a problem experienced in many higher education institutions world-wide as well as in South Africa. Literature shows that the problem is relatively well researched. Most of the research has taken place within the quantitative paradigm and in many cases focused on a search for determinants of possible success and / or failure in the subject or the factors contributing to the situation. The findings of all these research projects are varied and often inconclusive. It also becomes clear that the contexts of the studies are diverse, which makes it difficult for institutions and concerned lecturers to apply the findings in their specific situations. In this article the authors provide an overview of some of the most prominent research findings on factors determining or influencing success / failure in the field. They also attempt to organise these findings in a digestible way for the concerned lecturer and interested researcher. This is followed by a report on the first phase of an investigation into possible factors contributing to the low performance levels of students at a South African higher education institution. The unit of analysis is the first year accounting class of the first author (a lecturer at the institution). The research is quantitative in nature and statistical analyses are employed. In addition to factors such as age, gender, matric performance in key subjects, M-scores, class attendance and nationality, the investigation also looked at the levels of learning approach of the students as a possible determinant of success or failure. The findings are compared with the findings from literature and the implications of the research are discussed

Conception rates of Angora ewes inseminated with deepfrozen semen

No Abstrac

Training volume and injury incidence in a professional rugby union team

Objective. To describe the incidence of injuries in a professional rugby team, and to identify any associations between injury rates and training volume. Methods. This retrospective, descriptive study included all injuries diagnosed as grade 1 and above in a South African Super 12 rugby team. Injury incidence and injury rates were calculated and compared with training volume and hours of match play. Results. Thirty-eight male rugby players were injured during the study period. The total number of annual injuries decreased from 50 (2002) to 38 (2004) (χ2=0.84, p=0.36). The number of new injuries showed a similar trend (χ2=2.81, p=0.09), while the number of recurring injuries increased over the 3-year period. There was a tendency for total in-season injury rates to decrease over the 3 years (χ2=2.89, p=0.09). The pre-season injury rate increased significantly over the 3 years (χ2=12.7, p<0.01), coupled with a reduction in training exposure over the pre-season phase. Conclusions. One has to be cognisant of the balance between performance improvement and injury risk when designing training programmes for elite rugby players. Although the reduction in training volume was associated with a slight reduction in the number of acute injuries and in-season injury rates over the three seasons, the performance of the team changed from 3rd to 7th (2002 and 2004, respectively). Further studies are required to determine the optimal training necessary to improve rugby performance while reducing injury rates