2,210 research outputs found
Stomach content analyses of mullet from the Swartkops estuary
The stomach content of four species of mullet (Mugil cephalus, Liza dumerili, Liza richardsonii and Liza tricuspidens), was analyzed. The nature of the stomach content gave some indication of the areas in which each species of mullet had been feeding, the type of substratum from which each had been feeding and the diatom species which each ate
Effect of storage time and temperature on the volatile composition and quality of dry white table wines
Dry white wines of the cultivars Chenin blanc, Riesling and Colombar (1978 vintage) were stored at 0, 10, 20 and 30 °c for 12 months. Another Colombar wine (1977 vintage) was stored under similar conditions for 2 years. The 1978 wines were analysed periodically by gas chromatography for esters, higher alcohols and dimethyl sulphide and sensorily evaluated for young wine bouquet, maturation bouquet and total wine quality. Increases in storage time and temperature caused marked decreases in the concentrations of i-amyl acetate, hexyl acetate, 2-phenethyl acetate, ethyl butyrate, ethyl caproate, ethyl caprylate, ethyl caprate, total esters and young wine bouquet and marked increases in the· concentrations of dimethyl sulphide, diethyl succinate, ethyl acetate and total aldehydes as well as optical density and maturation bouquet. Highly significant relationships were found between chemical components and the percentage scores of the wines determined by sensory evaluations. The effect of time and temperature on the ageing of white wines can be utilized in practice either to preserve the young wine bouquet for an extended period of time or to produce a well-aged wine within a short period.Einfluß der Lagerungsdauer und -temperatur auf die Aromazusammensetzung und Qualität trockener weißer TafelweineTrockene Weißweine der Sorten Chenin blanc, Riesling und Colombar (Jahrgang 1978) wurden bei 0, 10, 20 und 30 °c 12 Monate lang gelagert. Ein anderer Colombar-Wein (Jahrgang 1977) wurde unter ähnlichen Bedingungen 2 Jahre lang gelagert. Die 1978er Weine wurden mittels Gaschromatographie regelmäßig auf Ester, höhere Alkohole und Dimethylsulfid analysiert sowie sensorisch auf Jungweinbukett, Reifebukett und gesamte Weinqualität geprüft. Zunehmende Lagerungsdauer und Lagerungstemperatur bewirkten eine deutliche Abnahme bei der Konzentration von iAmylacetat, Hexylacetat, 2-Phenyläthylacetat, Äthylbutyrat, Äthylcapronat, Äthylcaprylat, Äthylcaprinat, gesamten Estern und beim Jungweinbukett sowie eine ausgeprägte Zunahme bei der Konzentration von Dimethylsulfid, Dilithylsuccinat, Äthylacetat und gesamten Aldehyden, bei der optischen Dichte wie auch beim Reifebukett. Zwischen den Inhaltsstoffen und den Ergebnissen der sensorischen Prüfung wurden hochsignifikante Korrelationen gefunden. Der Einfluß von Lagerungsdauer und -temperatur auf die Alterung von Weißweinen kann praktisch genutzt werden, um entweder das Jungweinbukett über einen längeren Zeitraum hinweg zu erhalten oder um innerhalb kurzer Zeit einen angenehmen gealterten Wein zu erzielen
SALT Spectropolarimetry and Self-Consistent SED and Polarization Modeling of Blazars
We report on recent results from a target-of-opportunity program to obtain
spectropolarimetry observations with the Southern African Large Telescope
(SALT) on flaring gamma-ray blazars. SALT spectropolarimetry and
contemporaneous multi-wavelength spectral energy distribution (SED) data are
being modelled self-consistently with a leptonic single-zone model. Such
modeling provides an accurate estimate of the degree of order of the magnetic
field in the emission region and the thermal contributions (from the host
galaxy and the accretion disk) to the SED, thus putting strong constraints on
the physical parameters of the gamma-ray emitting region. For the specific case
of the -ray blazar 4C+01.02, we demonstrate that the combined SED and
spectropolarimetry modeling constrains the mass of the central black hole in
this blazar to .Comment: Submitted to Galaxies - Proceedings of "Polarized Emission from
Astrophysical Jets", Ierapetra, Crete, June 12 - 16, 201
Natural variation in abiotic stress responsive gene expression and local adaptation to climate in Arabidopsis thaliana.
Gene expression varies widely in natural populations, yet the proximate and ultimate causes of this variation are poorly known. Understanding how variation in gene expression affects abiotic stress tolerance, fitness, and adaptation is central to the field of evolutionary genetics. We tested the hypothesis that genes with natural genetic variation in their expression responses to abiotic stress are likely to be involved in local adaptation to climate in Arabidopsis thaliana. Specifically, we compared genes with consistent expression responses to environmental stress (expression stress responsive, "eSR") to genes with genetically variable responses to abiotic stress (expression genotype-by-environment interaction, "eGEI"). We found that on average genes that exhibited eGEI in response to drought or cold had greater polymorphism in promoter regions and stronger associations with climate than those of eSR genes or genomic controls. We also found that transcription factor binding sites known to respond to environmental stressors, especially abscisic acid responsive elements, showed significantly higher polymorphism in drought eGEI genes in comparison to eSR genes. By contrast, eSR genes tended to exhibit relatively greater pairwise haplotype sharing, lower promoter diversity, and fewer nonsynonymous polymorphisms, suggesting purifying selection or selective sweeps. Our results indicate that cis-regulatory evolution and genetic variation in stress responsive gene expression may be important mechanisms of local adaptation to climatic selective gradients
Ascorbic acid causes spuriously low blood glucose measurements
CITATION: Strijdom, J.G., Marais, B.J. & Koeslag, J.H. 1993. Ascorbic acid causes spuriously low blood glucose measurements. S Afr Med J, 83(1):64-65.The original publication is available at http://www.samj.org.za[No abstract available]Publisher’s versio
Africa’s neglected area of human resources for health research – the way forward
Building the skills for doing, managing and delivering healthresearch is essential for every country’s development. Yet humanresources for health research (HRHR) are seldom considered inAfrica and elsewhere. Africa’s health research capacity has grownconsiderably, with potential to increase this growth. However, asystemic way of defining, co-ordinating and growing the HRHRneeded to support health systems development is missing.Reviewing the status of HRHR in Africa, we assert that it consistsof unco-ordinated, small-scale activities, primarily driven fromoutside Africa. We present examples of ongoing HRHR capacitybuilding initiatives in Africa. There is no overarching framework, strategy or body for African countries to optimise research support and capacity in HRHR. A simple model is presented to help countries plan and strategisefor a comprehensive approach to research capacity strengthening.Everyone engaged with global, regional and national researchfor health enterprises must proactively address human resourceplanning for health research in Africa. Unless this is made explicitin global and national agendas, Africa will remain only an interestedspectator in the decisions, prioritisation, funding allocations,conduct and interpretation, and in the institutional, economic andsocial benefits of health research, rather than owning and drivingits own health research agendas
Faith formation of children : a practical theological study of child evangelism fellowship South African
Thesis (MTh)--Stellenbosch University, 2022.ENGLISH ABSTRACT: This research investigates the ministry of CEF in South Africa. As a para-church organisation operating in South Africa for over seventy years, this study seeks to establish the impact the ministry is making in enhancing the faith formation of South African children.
There is a growing concern amongst evangelical church leaders around the number of young people who are leaving the church in their teenage and early twenties. There are many reasons for this phenomenon but this research examines children’s ministry and the faith formation of children. The research argues that one factor that leads to youth and young adults leaving the church is the lack of spiritual grounding.
The research question explored in this study asks: In what ways can CEFSA provide a contextually relevant approach to assist South African children in the formation of their faith? Using the practical theology research methodology promoted by Osmer (2008), this research asks four questions: What is going on? Why is this going on? What ought to be going on? How might we respond? In response to these I undertook to understand the ministry and ministry methods of CEF international and its effectiveness in South Africa (chapter 1-2); to investigate the reasons for the current status of CEF in South Africa (chapter 2-3); to develop a theological approach to children’s ministry that will address the needs of South African children (chapter 4) and to develop a contextualized ministry approach to assist South African children with their faith formation (chapter 5).AFRIKAANSE OPSOMMING: Hierdie navorsing ondersoek die bediening van CEF in Suid-Afrika. As 'n para-kerklike organisasie wat vir meer as sewentig jaar in Suid-Afrika werksaam is, poog hierdie studie om die impak wat die bediening in die geloofsvorming van Suid-Afrikaanse kinders maak vas te stel.
Daar is 'n groeiende kommer onder evangeliese kerkleiers oor die aantal jongmense wat die kerk in hul tiener- en vroeë twintigerjare verlaat. Daar is baie redes vir hierdie verskynsel maar hierdie navorsing ondersoek kinderbediening en die geloofsvorming van kinders. Die navorsing voer aan dat een faktor wat lei na hoekom die jeug en jong volwassenes die kerk verlaat is die gebrek aan geestelike begronding in kinder jare.
Die navorsingsvraag wat in hierdie studie ondersoek is, vra: Op watter maniere kan CEFSA 'n kontekstueel relevante benadering verskaf om Suid-Afrikaanse kinders by te staan in die vorming van hul geloof? Deur gebruik te maak van die praktiese teologie navorsingsmetodologie wat deur Osmer (2008) bevorder is, vra hierdie navorsing vier vrae: Wat gaan aan? Hoekom gaan dit aan? Wat behoort aan te gaan? Hoe kan ons reageer? In reaksie hierop het ek onderneem om die bedienings- en bedieningsmetodes van CEF international en die doeltreffendheid daarvan in Suid-Afrika te verstaan (hoofstuk 1-2); om die redes vir die huidige status van CEF in Suid-Afrika te ondersoek (hoofstuk 2-3); om ’n teologiese benadering tot kinderbediening te ontwikkel wat die behoeftes van Suid-Afrikaanse kinders sal aanspreek te bespreek (hoofstuk 4) en om ’n gekontekstualiseerde bedieningsbenadering te ontwikkel om Suid-Afrikaanse kinders met hul geloofsvorming by te staan (hoofstuk 5).Master
The NOMA track module on nutrition, human rights and governance: Part 2. A transnational curriculum using a human rights-based approach to foster key competencies in nutrition professionals
Background. In response to the challenge of the global health needs of the 21st century, four academic institutions in Norway, South Africa and Uganda,each offering a Master’s degree in nutrition, collaboratively developed the NOrwegian MAsters (NOMA) track module on nutrition, human rights andgovernance, integrating a human rights-based approach into graduate education in nutrition.Objective. To capture students’ perceptions about the NOMA track module, focusing on the development of key competencies.Methods. Employing a qualitative approach, 20 (91% response rate) in-depth telephonic interviews were conducted with participating students, voicerecorded and transcribed. Through an inductive process, emerging themes were used to compile a code list for content analysis of the transcribed text. Relevant themes were reported according to the professionals’ roles described by the CanMEDS competency framework.Results. Participation in the module enhanced key competencies in the students, e.g. communication skills and the adoption of a holistic approach tointeraction with people or communities. Their role as collaborator was enhanced by their learning to embrace diversity and cultural differences and similarities. Students had to adapt to different cultures and educational systems. They were inspired to contribute in diverse contexts and act as agents for change in the organisations in which they may work or act as leaders or co-ordinators during interaction with community groups and policy makers. Higher education institutions offering transnational modules should support lecturers to manage the inherent diversity in the classroom as a way of enhancing student performance.Conclusion. The development of future transprofessional modules will benefit from the inclusion of desirable key competencies as part of the moduleoutcomes by following a competency by design process
Economic appraisal of dabigatran as first-line therapy for stroke prevention in atrial fibrillation
Background. Dabigatran is an oral anticoagulant direct thrombin inhibitor recently registered in South Africa (SA) to reduce the risk of stroke and systemic embolism in patients with atrial fibrillation (AF). Owing to the price disparity between warfarin (the current gold standard for treatment of patients with AF) and dabigatran, we conducted an economic appraisal of the use of dabigatran compared with warfarin from a payer perspective in the South African private healthcare setting.Objectives. To estimate the cost-effectiveness (CE) and budget impact of dabigatran compared with warfarin for the prevention of strokein AF patients.Methods. A previously published Markov model was populated with SA cost and mortality data to estimate the CE and budget impact analysis of dabigatran over a lifetime horizon. The model population consisted of a cohort of patients of whom those aged younger than 80 years used dabigatran 150 mg twice daily and those older than 80 years 110 mg twice daily. Modelled outcomes included total cost, qualityadjusted life years (QALYs) and incremental CE ratio (ICER), with the effectiveness measured by QALYs gained.Results. Dabigatran compared with warfarin as first-line treatment was estimated to have an ICER of R93 290 and an average incrementalcost per beneficiary per month of R0.39 over a 5-year period. Conservative assumptions were made regarding the number of international normalised ratio monitoring tests for patients on warfarin, and the ICER is estimated to decrease by as much as 15.7% under less stringent assumptions. A robust sensitivity analysis was also performed.Conclusion. Dabigatran as first-line treatment compared with warfarin for the use of stroke prevention in patients with AF is deemed costeffectivewhen used in accordance with its registered indication in the SA private sector
The importance of pharmacokinetics/pharmacodynamics assessment in Phase IIB/III trials for MDR-TB treatment
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