914 research outputs found
Identifying the challenges of creating an optimal dissemination geography for census
The importance of census data in government and private-sector planning cannot be underestimated. However, the geographic level at which it is made available for different users, is a highly debateable issue. It is crucial that census data is disseminated in such a way that it satisfies most user needs as far as possible, to ensure that there is optimum use of the information and that maximum value for money is provided. In the past, Statistics South Africa disseminated data at the same geographic level created for data collection. This causes problems for data users and calls for the creation of a separate output geography rather than using the original collection geography.The research was done on two levels: first, an overview of output geographies, as well as examples of developed and successfully used tools to generate these areas within a geographical information system. Some of these could be used in the South African milieu. Secondly the paper discuss aspects such as the population size variation of EAs, in order to inform the criteria for the creation of the ideal small area (SA) layer to satisfy the majority of user needs. Lastly the paper describes briefly the challenges faced to create the 2011 output geography. The results indicate a strong resemblance between the two EA population size patterns of 2001 and 2011, influenced by the EA demarcation rules. The challenges identified in the process of creating the SAL as a census output geography need to be taken into consideration to enable a more useful and user-friendly output
Particulate matter air pollution exposure: role in the development and exacerbation of chronic obstructive pulmonary disease
Due to the rapid urbanization of the world population, a better understanding of the detrimental effects of exposure to urban air pollution on chronic lung disease is necessary. Strong epidemiological evidence suggests that exposure to particulate matter (PM) air pollution causes exacerbations of pre-existing lung conditions, such as, chronic obstructive pulmonary disease (COPD) resulting in increased morbidity and mortality. However, little is known whether a chronic, low-grade exposure to ambient PM can cause the development and progression of COPD. The deposition of PM in the respiratory tract depends predominantly on the size of the particles, with larger particles deposited in the upper and larger airways and smaller particles penetrating deep into the alveolar spaces. Ineffective clearance of this PM from the airways could cause particle retention in lung tissues, resulting in a chronic, low-grade inflammatory response that may be pathogenetically important in both the exacerbation, as well as, the progression of lung disease. This review focuses on the adverse effects of exposure to ambient PM air pollution on the exacerbation, progression, and development of COPD
A study of the relationship between health awareness, lifestyle behaviour and food label usage in Gauteng
Background: The objectives of the study were to determine whether consumers who read food labels, were also more aware of health and lifestyle issues, in terms of nutrition and other health-related lifestyle behaviours, and whether there was a relationship between food-label reading, health awareness and lifestyle behaviour. A quantitative descriptive (survey) design was selected to investigate the relationship between food-label reading on the one hand, and health awareness and lifestyle behavior on the other.Method: A two-stage, stratified-proportionate and systematic sampling strategy was applied to select a sample of 357 Gauteng respondents to complete a telephonic questionnaire. Respondents who were most likely to read food label information were selected. Food label information is prescribed by comprehensive label legislation. Data report on respondents’ label-reading habits, attitudes towards health awareness, lifestyle behaviour and biographic data. Nonparametric analysis, scale reliability tests, analysis of variance (ANOVA) and Bonferroni multiple comparisons of means tests were used to analyse the results.Results: Results indicate that the two-thirds of respondents who, to some extent read nutritional information on food labels, were concerned about their personal health, were interested in health-related information, and followed a healthy lifestyle, such as regularly eating fresh fruit and vegetables, cutting back on alcohol, and other positive lifestyle behaviours. They were unsure about how their own knowledge of nutrition,and their understanding of nutrition information on food labels, compared with that of other consumers.Conclusion: A relationship was found between patterns of reading food labels, health awareness and lifestyle behaviour. People who often read food labels were more health-conscious, and maintained a healthier lifestyle.Keywords: health awareness, lifestyle, food labels, South Africa, consumer
Forecasting South African containers for international trade : a commodity-based approach
The original publication is available at http://www.jtscm.co.za/index.php/jtscm/article/view/72The most common approach used internationally for forecasting international trade
containers is models based on the correlation between container trade and economic
growth. While the strong historical correlation is indisputable, this paper argues that
there will be saturation in the propensity to containerise as all the suitable volumes of
the underlying commodities shift to containers over time. In addition, the link between
freight transport and GDP will decouple as more sustainable approaches to economic
development, and therefore freight transport, are necessitated by economic and
environmental realities. A commodity-based model, taking into account the underlying
drivers of containerisation, is proposed here as a more realistic forecast of container
demand. This could have a material impact on how large-scale investment decisions are
directed.Publishers' Versio
A Multivariate Test of the Null Hypothesis That Two Populations Do Not Differ in the Direction of Their Mean Vectors
1 online resource (PDF, 6 pages
Neurodevelopmental evaluation and referral practices in children with congenital heart disease in central South Africa
Introduction: Children with congenital heart disease (CHD) are at higher risk for developmental delays than the general population. The American Heart Association (AHA) published a guideline to address these concerns in 2012. This study determined the neurodevelopmental evaluation and referral practices of practitioners in central South Africa.Method: An online survey was administered to practitioners (n=45) including paediatric cardiologists (n=4), cardiothoracic surgeons (n=4) and general paediatricians (n=37). Information on practitioner characteristics, awareness of the 2012 AHA guideline; and neurodevelopmental evaluation and referral practices was collected.Results: Twenty-one practitioners responded, including paediatric cardiologists (n=4), cardiothoracic surgeons (n=2) and paediatricians (n=15). Data for 20 practitioners was included. Despite most practitioners (n=18) indicating guidelines for the management of development were important, the majority (n=16; 80%) were unaware of the guideline. Most practitioners (n=18; 90%) failed to risk stratify children to identify those to be evaluated. Children with developmental delays were referred for formal developmental evaluation (n=11; 55%) and to intervention therapies (n= 15; 75%).Conclusion: Most practitioners are unaware of the 2012 AHA guideline. Awareness of the developmental risks associated with CHD and implementation of the guideline could promote early identification of developmental delays with referral to intervention therapies
An Application Of Multivariate Analysis To Some Tranquilzer Comparison Experiments
1 online resource (PDF, 13 pages
Bidirectional crosstalk between hypoxia-inducible factor and glucocorticoid signalling in zebrafish larvae
In the last decades in vitro studies highlighted the potential for crosstalk between Hypoxia-Inducible Factor-(HIF) and glucocorticoid-(GC) signalling pathways. However, how this interplay precisely occurs in vivo is still debated. Here, we use zebrafish larvae (Danio rerio) to elucidate how and to what degree hypoxic signalling affects the endogenous glucocorticoid pathway and vice versa, in vivo. Firstly, our results demonstrate that in the presence of upregulated HIF signalling, both glucocorticoid receptor (Gr) responsiveness and endogenous cortisol levels are repressed in 5 days post fertilisation larvae. In addition, despite HIF activity being low at normoxia, our data show that it already impedes both glucocorticoid activity and levels. Secondly, we further analysed the in vivo contribution of glucocorticoids to HIF activity. Interestingly, our results show that both glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) play a key role in enhancing it. Finally, we found indications that glucocorticoids promote HIF signalling via multiple routes. Cumulatively, our findings allowed us to suggest a model for how this crosstalk occurs in vivo
Endoscopic tri-modal imaging for surveillance in ulcerative colitis: randomised comparison of high-resolution endoscopy and autofluorescence imaging for neoplasia detection; and evaluation of narrow-band imaging for classification of lesions
Background: Endoscopic tri-modal imaging (ETMI) incorporates white light endoscopy (WLE), autofluorescence imaging (AFI) and narrow-band imaging (NBI). Aims: To assess the value of ETMI for the detection and classification of neoplasia in patients with longstanding ulcerative colitis. Design: Randomised comparative trial of tandem colonoscopies. Setting: Academic Medical Centre Amsterdam, Netherlands. Patients and methods: Fifty patients with ulcerative colitis underwent surveillance colonoscopy with ETMI. Each colonic segment was inspected twice, once with AFI and once with WLE, in random order. All detected lesions were inspected by NBI for Kudo pit pattern analysis and additional random biopsies were taken. Main outcome measures: Neoplasia miss-rates of AFI and WLE, and accuracy of the Kudo classification by NBI. Results: Among patients assigned to inspection with AFI first (n = 25), 10 neoplastic lesions were primarily detected. Subsequent WLE detected no additional neoplasia. Among patients examined with WLE first (n = 25), three neoplastic lesions were detected; subsequent inspection with AFI added three neoplastic lesions. Neoplasia miss-rates for AFI and WLE were 0% and 50% (p = 0.036). The Kudo classification by NBI had a sensitivity and specificity of 75% and 81%; however, all neoplasia was coloured purple on AFI (sensitivity 100%). No additional patients with neoplasia were detected by random biopsies. Conclusion: Autofluorescence imaging improves the detection of neoplasia in patients with ulcerative colitis and decreases the yield of random biopsies. Pit pattern analysis by NBI has a moderate accuracy for the prediction of histology, whereas AFI colour appears valuable in excluding the presence of neoplasia. Trial registration number: ISRCTN0527274
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