Economic growth and obesity in South African adults: an ecological analysis between 1994 and 2014

Abstract: To assess the trend associations between South Africa’s economic growth using various economic growth indicators (EGIs) with adult obesity prevalence over a specified period of time. Methods: Data for obesity levels reported was obtained from national surveys conducted in South African adults between the periods of 1994 to 2014. EGIs incorporated in the current analysis were obtained from the World Bank and IHS Global insight databases. Obesity prevalence is presented by gender, urbanisation level and ethnicity. EGIs congruent to the time points where obesity data are available are presented. Unadjusted time trend plots were applied to assess associations between obesity prevalence and EGIs by gender, urbanisation level and ethnicity. Results: Females present higher levels of obesity relative to males for all time points. For both males and females, an overall increase in prevalence was observed in both rural and urban settings over‐time, with urban dwellers presenting higher obesity levels. An overall increase in Gross Domestic Product (GDP) per capita and Household Final Consumption Expenditure (HFCE) per capita was observed. The Gini coefficient for all ethnicities except the white group increased between 1998 and 2003 but declined by 2012

Evaluation of chicken blood and maize stover compost as a nitrogen source for maize

Organic materials are an important source of nutrients for many smallholder farmers. The use of composted organic amendments is constrained by their variability and maturity. The aim of this study was to evaluate the potential of aerobically composted chicken blood and maize stover mixtures on maize N uptake and to determine the effect on seed emergence in a greenhouse pot experiment. Four composts with proportions of 10%, 30%, 70% and 100% maize stover were used as soil amendments and compared against an unamended soil (control). The greenhouse pot experiment involved planting 10 maize seeds in each pot. Seed emergence percent was determined a week after sowing to ascertain whether the composts had phytotoxic effects. Percent emergence did not differ significantly among treatments (p =0.26). Two plants were allowed to grow in the pots for five weeks after which maize dry matter yield and foliar analysis followed. The foliar samples were analysed for total nitrogen, dry matter yield and cations (Mg, Ca, K and Na). Nitrogen uptake differed significantly among treatments and ranged from 0.27% to 0.75%. Nitrogen uptake was higher in soils amended with 10% and 30% maize stover compost treatments. Dry matter yield also differed significantly ranging from 1.09g to 2.2g per pot). Uptake of all cations did not differ (p>0.05) significantly among treatments. The 10% and 30% maize stover composts had greater potential to support maize growth as shown by the dry matter yield and total N concentrations in the plant samples

Economic growth as an underlying probable systemic driver for childhood obesity in South Africa: A Joinpoint regression and ecological analysis over 10 years

Background. Childhood obesity has become a global public health problem and is a known risk factor for type 2 diabetes, cardiovascular disease, hypertension, stroke, myocardial infarction and various cancers in later adulthood.Associations between adult obesity and economic growth, technological changes, socioeconomic status and economic inequities have been reported, but limited data are available for children and adolescents in countries that are undergoing an epidemiological health transition exhibiting both under- and overnutrition.Objectives. To demonstrate childhood obesity trends and explore their associations with economic growth in South Africa (SA).Methods. This was a retrospective review and analysis of obesity and economic growth trends in SA. Data for obesity levels were obtained from national surveys conducted in SA youths in 2002, 2008 and 2012. Economic growth indicators (EGIs), namely gross domestic product (GDP) per capita, household final consumption expenditure and Gini coefficient, were obtained from the World Bank and IHS Global Insight databases. Obesity trends for 2002 - 2012 are presented by gender and ethnicity. Annual percentage changes (APCs) in obesity prevalence were computed to assess obesity trends using the linear Joinpoint regression.Results. An overall increase in obesity prevalence over time from 3.8% to 6.0% was observed. Females had higher levels across all time points. APCs in both males (7.8%; 95% confidence interval (CI) 0.3 - 15.9; p=0.01) and females (3.1%; 95% CI –14.7 - 24.7; p=0.30) were observed. Among black Africans, coloureds and whites, females had higher obesity levels than males for the three time points. For males, the prevalence of obesity was highest in whites and Asians/Indians, whereas coloureds and blacks had lower levels across all time points. However, the black male population had the highest APC increase (9.4%; 95% CI –23.0 - 55.3; p=0.20). The prevalence of obesity was positively and inversely associated with GDP per capita and the Gini coefficient, respectively.Conclusions. An increase in childhood and adolescent obesity over time was observed, while trend associations between obesity and EGIs exist

Plagiarism : student perspectives

Abstract: Context. Universities are often required to lay the ethical foundation of student behaviour and none is more prevalent than the issue of plagiarism. Plagiarism is a violation of academic integrity although it is not specific to the academic community alone. The aim of this paper is to assess students’ understanding of plagiarism and plagiarism policies, the extent to which they engage in plagiarism practices, and their perceptions on the adequacy of training workshops on writing practices for undergraduate and post-graduate students at a metropolitan university in South Africa. Problem and results. Contradictory evidence was found about the students’ understanding of plagiarism. The prevalence of plagiarism was perceived as low amongst students. The students seemed to understand plagiarism policies as the majority indicated awareness of departmental penalties for student plagiarism and perceived these penalties to be fair. Additionally, the results revealed that different faculty departments placed equal emphasis on plagiarism and that the students perceived the university and the department’s workshops on academic writing and plagiarism to be adequate. Solution. This study highlights that South African universities mirror the global trend of increasing student plagiarism practices and that efforts to improve academic integrity should adopt global best practices while taking into account local characteristics

Age-dependence of electromagnetic power and heat deposition in near-surface tissues in emerging 5G bands

With the development of 5th generation (5G) mobile networks people of different ages will be exposed in the upper part of the microwave spectrum. From the perspective of non-ionizing radiation dosimetry, an accurate analysis of age-dependent electromagnetic power deposition and resulting heating is required. In this study, we evaluate the effect of age on exposure at 26 GHz and 60 GHz. A near-surface tissue model illuminated by a plane wave is used to asses the exposure considering both frequency-independent and frequency-dependent limits. The age-related variation of the skin thickness and tissue electromagnetic properties has been considered. Moreover, the blood flow decrease rate has been taken into account to assess the age-dependent heating. Our results demonstrate that the overall variations of the power density, specific absorption rate (SAR) and heating in the near-surface tissues are limited to about 10–15%. These variations are mainly due to the tissue permittivity and blood flow change with age. In contrast to the transmitted power density that increases with age, the peak SAR decreases at both frequencies. The peak steady-state heating increases from 5 to 70 years old by roughly 11% at 26 GHz and 13% at 60 GHz