A comparison in university students of the amplitude of accommodation determined subjectively

Background: Historically, the push-up and the minus lens methods have been used for the measurements of the amplitude of accommodation, and the differences between the results of these methods are well known. Aim: The purpose of this study was to compare three methods for determining the monocular amplitude of accommodation and consider whether agreement exists between such methods. Setting: The study was conducted at the Optometry Clinic, University of Limpopo. Method: Thirty-four (N = 34) African optometry students participated in this study. There were 20 female and 14 male students. The age range of the participants was 20–34 years. Amplitude of accommodation was measured via the subjective push-up, push-down and minus lens methods only on the right eyes of the sample. Results: The highest average amplitude of accommodation was obtained with the push-up method (10.20 D ± 0.96 D), while the minus lens method produced the smallest mean amplitude of accommodation (9.66 D ± 0.75 D). A higher correlation was found between the push-up and push-down methods (r = 0.80, p = 0.06). The smallest correlation was observed between the push-up and the minus lens methods (r = 0.60, p = 0.062). There were no statistically significant differences between the amplitude of accommodation in male and female students for all three methods (p > 0.005). Conclusion: It seems easier to recognise the point where one can identify a target in pushdown amplitude than the point of first sustained blur in the push-up method. The push-up method tends to overestimate the actual amplitude of accommodation because of the effects of depth of focus. The less evaluated method in the literature is the push-away method; however, further research is necessary to answer the question of which (if any) method is more accurate

Working towards an increase in manganese ferroalloy production in South Africa - a research agenda

CITATION: Steenkamp, J. D., et al. 2018. Working towards an increase in manganese ferroalloy production in South Africa - a research agenda. Journal of the Southern African Institute of Mining and Metallurgy, 118(6):645-654, doi:10.17159/2411-9717/2018/v118n6a13.The original publication is available at http://www.scielo.org.zaAlthough South Africa is endowed with one of the largest land-based deposits of manganese ore, in the order of 80% of the ore mined is exported for beneficiation elsewhere. The past 15 years has seen a decline in the production of manganese ferroalloys locally due to a steep rise in the price of electricity, among other factors. As local beneficiation of South Africa's resources is a national priority, a research agenda to increase manganese ferroalloy production in South Africa was developed. Inputs were obtained from various role-players in the value chain, including local smelter operations, research institutions both local and abroad, and companies providing support to the industry. Ninety-five research opportunities were identified and grouped into twenty-one research themes. The results are reported here in the context of a review of relevant Infacon papers and Mintek reports. As implementation of such a research agenda could be done through the development of a technology roadmap, the paper concludes with an example from Norway where a roadmap was developed to increase the use of natural gas in metal production.http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S2225-62532018000600016Publisher's versio

“Motherhood is hard” : exploring the complexities of unplanned motherhood among HIV-positive adolescents in South Africa

Abstract: For any woman, pregnancy and giving birth are major life-changing experiences. This period is argued to indicate a shift from girlhood into womanhood. However, this experience takes on new meaning when the woman is very young—an adolescent, who is still in school—and learns that she is HIV-positive. For such adolescent, becoming a mother, just like living with HIV/ AIDS, involves moving from a known, current reality to an unknown, new reality. To understand how HIV-positive adolescent mothers grapple with the demands and responsibilities of unplanned motherhood while living with HIV, this study explores the complexities of their experiences in South Africa. Drawing on qualitative methods, this study examines their meaning to motherhood while meeting their personal health needs. Through in-depth interviews conducted among 10 HIV-positive adolescent mothers living in Johannesburg, this article presents an empirical study of their narratives and how they negotiate these complexities in their unplanned new realities. Emerging themes from the interview transcripts were identified, coded, and analyzed thematically following an interpretivist approach. From the interviews conducted, it is evident that HIV-positive adolescent mothers perceive unplanned motherhood as difficult and this negatively affects their future childbearing decisions. Given the importance of motherhood and adolescents globally, this article advocates for feminist policies that would facilitate larger transformative narratives. It also recommends the implementation of relevant policy that would alleviate the difficulties of HIV-positive adolescent mothers generally