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Dietary diversity and its association with anaemia in pregnant women in the Roodepoort area of Johannesburg, Gauteng of Johannesburg, Gauteng
No full textText in EnglishAnaemia is a global public health concern, especially in low and middle-income countries such as South Africa. This dissertation aimed to investigate the association between anaemia prevalence and dietary diversity in pregnant women in the Roodepoort area of Johannesburg, Gauteng, South Africa. A cross-sectional study was conducted on 294 pregnant women attending the Discoverers Community Health Centre in Johannesburg. An interviewer-administered questionnaire and medical files were utilised to obtain socio-demographic and obstetric history data, respectively. Trained fieldworkers conducted anthropometrical measurements. Dietary diversity (DD) was assessed using the 24-hour recall method and a DD score (DDS) calculated, and haemoglobin levels were measured to determine anaemia status. Statistical analyses included descriptive data analysis, independent t-tests, ANOVA, Chi-square analysis and determining the Pearson’s correlation coefficient. The mean age of the participants was 28.6 (± 5.8) years. Most women were from South Africa (66.8%), Black African women (90%), single (44.9%), and unemployed (56.8%). The majority of the participants were in their second trimester (59.3%) and were HIV negative (78.9%). The mean Hb for the total sample was 11.6 (±1.35) g/dL. No participants in this study were classified as severely anaemic (< 7 g/dL), however 22.9% were anaemic (< 10.5 g/dL). HIV positive participants had lower Hb levels (11.0±1.50 g/dL) compared to HIV negative participants (11.8±1.26 g/dL) (p = 0.006). From the 24-hour dietary recall results, majority food groups consumed included grains, roots, and tubers (99.3%), meat, poultry and fish (82.9%), and vegetables not high in vitamin A (61.2%). Food groups consumed the least included nuts and seeds (11.5%), pulses (11.9%), eggs (17.5%), and dark green leafy vegetables (23.4%). The mean DDS was 4.21 (± 1.38). Majority of the study sample (60.8%) did not meet the required minimum DD for women ≥ 5 food groups. Contrary to some existing literature, this study found no correlation between anaemia prevalence and dietary diversity amongst pregnant women. Possible reasons for this dissociative relationship are discussed and include nutritional interventions such as the national food fortification program, the use of micronutrient supplementation and various socio-economic factors. The findings underscore the complexity of anaemia in pregnancy and highlight the need for tailored interventions to address nutritional deficiencies and socio-economic determinants.
Further research is required to explore additional factors contributing to anaemia in pregnant women and to develop comprehensive strategies for the prevention and management thereof not only in the Roodepoort area in Johannesburg, but also in the wider population of South Africa.M.C.S. (Consumer Science)Life and Consumer Science
Driver yield and safe child pedestrian crossing behavior promotion by a school traffic warden program at primary school crossings: A cluster- randomized trial
Get PDFObjective: To determine the effect of a school traffic warden program on increasing driver yield and safe child pedestrian crossing behavior in Kampala, Uganda. Methods: We designed and implemented a school traffic warden program in specific school zones in Kampala, Uganda. We randomly assigned 34 primary schools in Kampala, in a 1:1 ratio, using a computer-generated randomization sequence, to control or intervention arms in a cluster randomized trial. Each school in the intervention group received one trained adult traffic warden stationed at roads adjacent to schools to help young children safely cross. The control schools continued with the standard of care. We extracted and coded outcome data from video recordings on driver yield and child crossing behavior (defined as waiting at the curb, looking both ways for oncoming vehicles, not running while crossing, and avoiding illegal crossing between vehicles) at baseline and after 6 months. Using a mixed effect modified Poisson regression model, we estimated the prevalence ratio to assess whether being in a school traffic warden program was associated with increased driver yield and safe crossing behavior. Results: A higher proportion of drivers yielded to child pedestrians at crossings with a school traffic warden (aPR 7.2; 95% CI 4.42–11.82). Children were 70% more likely to demonstrate safe crossing behavior in the intervention clusters than in control clusters (aPR 1.7; 95% CI 1.04–2.85). A higher prevalence was recorded for walking while crossing (aPR 1.2; 95% CI 1.08–1.25) in the intervention clusters. Conclusion: The school traffic warden program is associated with increased driver yield and safe child pedestrian crossing behavior, i.e., stopping at the curb, walking while crossing, and not crossing between vehicles. Therefore, the school traffic warden program could be promoted to supplement other road safety measures, such as pedestrian safety road infrastructure, legislation, and enforcement that specifically protects children in school zones.Institute for Social and Health Studies (ISHS
Accessing collective memory: case study of a South African nature conservation institution
Get PDFAs a government body, South African National Parks (SANParks) is responsible for nature conservation, tourism and socio-economic development of communities neighbouring the national game reserves. Government bodies, like SANParks, fall within the scope of public entities that must comply with the South African national archive legislation. According to Sections 3(a) and (b) of the National Archives and Records Service Act, No. 43 of 1996, two of the objectives of the National Archives are to preserve public and non-public records with enduring value for use by the public and the State; and to make such records accessible, while promoting their public use. Section 12(1) of the National Archives and Records Service Act requires public records that are regarded as having enduring value to be made available to the public, when the period of 20 years has elapsed, since the end of the year in which the records have come into existence. SANParks has a wealth of information stored in its archives, which should be made available to interested members of the public. As remarked by Ngoepe (2019), SANParks has the capability of enabling the South African National Archives to build an inclusive archive in South Africa by participating and opening their collections for public access. Apart from discussing the challenges associated with accessing such archival collections and the lack of interest in assisting SANParks in ensuring the availability of their collections, this paper proposes potential solutions to make valuable collections, including oral history collections, housed by South African government bodies available to interested members of the public.Information Scienc
Intelligent fault detection technique for distribution network with interconnected distributed generation sources
No full textText in EnglishMachine Learning (ML) or Artificial Intelligence (AI) approaches in a distribution protection system are proposed to detect and categorize distribution network (DN) issues with Distribution Generation. This study highlights an important but generally overlooked distribution generation feature in energy transformation. Distributed generators (DGs) integrated into Distribution Network (DN) capability improve power quality, system dependability, voltage sags, and emergency backup during protracted grid outages. A technical and global analysis of DG technology's increased penetration is revealing its effects such as the utility systems undergoing elevated fault current and load flow changes, which will affect current protective relaying, particularly overcurrent relays. A protective system that can respond to the new dynamic DN is required to avoid consequences. Intelligent protection system application is a suitable distribution network solution for the explained challenge.
The study conducts a thorough assessment of various methods used in detection and diagnostic systems inside distribution networks that have interconnected distributed generators (DGs). The study specifically emphasizes the implementation of intelligence-based approaches. This evaluation is conducted through a thorough literature review. A comprehensive model of a distribution network, encompassing all essential components, was constructed and subjected to simulation. This model incorporated all pertinent parameters associated with the distribution network. Subsequently, several forms of faults were intentionally introduced at a specific point inside the micro-grid. The purpose of this exercise is to gather voltage and current signals at the busbar and then the collected data is subsequently transformed into numerical values to facilitate machine-learning modelling. The implementation of intelligent approach for fault detection in distribution networks with various machine-learning techniques, allows the approach to form part of the objective to gather related signals that are pre-processed as variable features in order to extract required data that can help identify distribution network and classify faults at most efficient and accurate way. The primary objective of the protection system was to analyze the underlying failure mode, determine the fault type quickly and accurately, and identify the faulty line in the system.
S shows the micro-grid's successful operation with current and voltage signals evidently shown . The current and voltage signals are transformed to numerical values for feature extraction which is key requirement for machine learning modelling. The derived variable features from feature extraction were trained and tested to validate fault diagnosis and classification to find the best machine learning fault classifier, Support vector machine (SVM) classifiers shows excellent results with 99.9% accuracy in validation and testing. These accuracy results meet the difficult requirements of a micro grid protection systems and SVM's ability to simulate non-linear decision boundaries, which is valuable in many applications.M. Sc. (Engineering)Engineerin
Search for light long-lived neutral particles from Higgs boson decays via vector-boson-fusion production from pp collisions at s = 13 TeV with the ATLAS detector
No full textAbstract
A search is reported for long-lived dark photons with masses between 0.1 GeV and 15 GeV, from exotic decays of Higgs bosons produced via vector-boson-fusion. Events that contain displaced collimated Standard Model fermions reconstructed in the calorimeter or muon spectrometer are probed. This search uses the full LHC Run 2 (2015–2018) data sample collected in proton–proton collisions at
s
=
13
TeV, corresponding to an integrated luminosity of 139
f
b
-
1
. Dominant backgrounds from Standard Model processes and non-collision sources are estimated using data-driven techniques. The observed event yields in the signal regions are consistent with the expected background. Upper limits on the Higgs boson to dark photon branching fraction are reported as a function of the dark photon mean proper decay length or of the dark photon mass and the coupling between the Standard Model and the potential dark sector. This search is combined with previous ATLAS searches obtained in the gluon–gluon fusion and WH production modes. A branching fraction above 10% is excluded at 95% CL for a 125 GeV Higgs boson decaying into two dark photons for dark photon mean proper decay lengths between 173 and 1296 mm and mass of 10 GeV
Pausing as a strategic practice amidst a grand challenge in credit risk in an African Bank
No full textText in English, with abstracts and keywords in English, Afrikaans and ZuluThe study set out to explore the practice of pausing during a grand challenge (Covid-19), from the progressive perspective of strategy-as-practice. It discerned the influence of pausing during the implementation phase of a credit risk change intervention in an African bank, emphasising greater transparency and inclusiveness through diverse practitioners in Africa. The methodological approach involved a single case study guided by qualitative research methods to answer the research questions that framed the study. The research explored the micro-level strategising practices within a single case organisation across different countries examining adaptive practitioners and their pausing behaviours as the unit of analysis. Pausing, an intangible and under-theorised practice, is positioned as a theoretical and applied gap in existing literature. The study offers a comprehensive literature review, demonstrating the limited theoretical positions on embodied, intentional, or intuitive practices, such as pausing, as strategic practices. Fundamentally, this study contributes an incremental extension of theory and knowledge on pausing as an unconventional action, and additionally aims to determine the influence of pausing in accomplishing or deterring strategy work during a time of great challenge. Findings showed that pausing is a human-lived and strategic practice, which is either intuitive or intentional. Pausing can be enabling during times of uncertainty and complexity (such as grand challenges like Covid-19). Humans, as adaptive practitioners, can influence strategy amidst a grand challenge by pausing as part of their adaptivity. Together, these assertions ultimately contribute to organisational outcomes, not only in business-as-usual circumstances, but also in times of uncertainty or crisis. Modest ideas are offered by positioning pausing as a sincere dimension of broader open strategy within the global context of ‘big’ or macro grand challenge strategy, yet still anchored in the ‘small’ and micro strategy of the case. Notwithstanding certain methodological limitations and implications, the case offered insights for theorising about, and practicing around, the ‘silent’ dimensions of strategy.Die studie het ten doel gehad om die praktyk van pousering gedurende ’n groot uitdaging (soos Covid-19) vanuit ’n progressiewe perspektief van strategie-as-praktyk te verken. Dit het die invloed van pousering gedurende die implementeringsfase van ’n kredietrisiko-veranderingsintervensie in ’n Afrika-bank onderskei en groter deursigtigheid en inklusiwiteit deur uiteenlopende praktisyns in Afrika beklemtoon. Die metodologiese benadering het ’n enkele gevallestudie gerig deur kwalitatiewe navorsingsmetodes betrek ten einde die navorsingsvrae te beantwoord wat as raamwerk vir die studie gedien het. Die navorsing het mikrovlak-strategiepraktyke binne ’n enkelgevalorganisasie regoor verskillende lande verken en aanpasbare praktisyns en hul pouserende gedrag as die eenheid van analise ondersoek. Pousering as ’n ondefinieerbare en gebrekkig geteoretiseerde praktyk is geposisioneer as ’n teoretiese en toegepaste gaping binne die bestaande literatuur. Die studie bied ’n omvattende literatuuroorsig en demonstreer die beperkte teoretiese posisies ten opsigte van vergestalte, intensionele of intuïtiewe praktyke soos pousering as strategiese praktyke. Hierdie studie dra fundamenteel by tot ’n inkrementele uitbreiding van teorie en kennis oor pousering as ’n onkonvensionele aksie en het bykomend ten doel om die invloed van pousering in die uitrig- of afskrikstrategiewerk gedurende ’n tyd van groot uitdagings, te bepaal. Die bevindinge het getoon dat pousering ’n mens-geleefde en strategiese praktyk is wat óf intuïtief óf intensioneel is. Pousering kan geaktiveer word gedurende tye van onsekerheid en kompleksiteit (soos ten tye van groot uitdagings soos Covid-19). Mense as aanpasbare praktisyns kan strategie te midde van groot uitdagings beïnvloed deur te pouseer as deel van hul aanpasbaarheid. Hierdie stellings dra uiteindelik gesamentlik by tot organisatoriese uitkomste nie net tydens normale omstandighede nie, maar ook in tye van onsekerheid of krisis. Beskeie idees word aangevoer ten einde pousering te posisioneer as ’n opregte dimensie van breër ope strategie binne die globale konteks van “groot” of makro uitdagingstrategie onderwyl dit steeds geanker bly in die “klein” en mikro-strategie van die geval. Ondanks sekere metodologiese beperkinge en implikasies het die geval insigte gebied om te teoretiseer oor, en te praktiseer binne die “stille” dimensies van strategie.Ucwaningo luhlose ukuhlola umkhuba wokumisa isikhashana ngesikhathi senselela enkulu (njenge-Covid-19), ngokombono oqhubekayo wesu-njengomkhuba. Lubone umthelela wokumisa isikhashana phakathi nesigaba sokuqaliswa sokungenelela ekuguquleni ubungozi bezikweletu ebhange lase-Afrika, okugcizelela ukuveza izinto obala kanye nokubandakanywa kwabantu bonke ngokusebenzisa ongoti abahlukahlukene e-Afrika. Indlela yokwenza ibandakanya isifundo socwaningo esisodwa esiholwa yizindlela zocwaningo oluchazayo ukuze kuphendulwe imibuzo yocwaningo eyakha ucwaningo. Ucwaningo luhlole izinqubo zokuhlela amazinga amancane ngaphakathi kwenhlangano yesifundo socwaningo esisodwa kuwo wonke amazwe ahlukene ehlola abasebenzi abaguquguqukayo kanye nokuziphatha kwabo kokumisa isikhashana njengeyunithi yokuhlaziya. Ukumisa isikhashana, umkhuba ongaphatheki futhi ongenayo inkolelo-mbono, kubekwa njengegebe lombono nosetshenziswayo ezincwadini ezikhona. Ucwaningo lunikeza ukubuyekezwa okubanzi kwezincwadi, okubonisa izikhundla ezilinganiselwe zombono mayelana nemikhuba ehlanganisiwe, eyinhloso, noma enembile, njengokumisa isikhashana, njengemikhuba yamasu. Ngokuyisisekelo, lolu cwaningo lunikela ngokunwetshwa kombono nolwazi ekumiseni okwesikhasana njengesenzo esingajwayelekile, futhi luhlose ukunquma umthelela wokumisa isikhashana ekufezeni noma ukuvimbela umsebenzi wesu ngesikhathi senselela enkulu. Okutholakele kubonise ukuthi ukumisa isikhashana kuwumkhuba ophilwa umuntu futhi onamasu, okungenzeka ukuthi uyazibonela noma uhlose. Ukumisa isikhashana kungavumela ngezikhathi zokungaqiniseki nokuba yinkimbinkimbi (njengezinselela ezinkulu njenge-Covid-19). Abantu, njengabasebenzi abaguquguqukayo, bangathonya isu ngesikhathi senselela enkulu ngokuma isikhashana njengengxenye yokuzivumelanisa nezimo. Ngokuhlangene, lezi zisho ekugcineni zinomthelela emiphumeleni yenhlangano, hhayi kuphela ezimeni zebhizinisi njengenjwayelo, kodwa nasezikhathini zokungaqiniseki noma zenhlekelele. Imibono enesizotha inikezwa ngokumisa ukuma isikhashana njengengxenye eqotho yesu elivulekile elibanzi ngaphakathi komongo womhlaba wonke wesu lenselela enkulu ‘enkulu’ noma enkulu, nokho isabambelele eswini ‘elincane’ nelincane lesifundo socwaningo. Naphezu kwemikhawulo ethile yendlela kanye nemithelela, isifundo socwaningo sinikeze imininingwane yokucabanga mayelana, nokuzijwayeza ngokuzungezile, ubukhulu besu 'buthule'.D. Phil. (Management Studies)Centre for Business Manangemen
Search for heavy Higgs bosons with flavour-violating couplings in multi-lepton plus b-jets final states in pp collisions at 13 TeV with the ATLAS detector
No full textAbstract
A search for new heavy scalars with flavour-violating decays in final states with multiple leptons and b-tagged jets is presented. The results are interpreted in terms of a general two-Higgs-doublet model involving an additional scalar with couplings to the top-quark and the three up-type quarks (ρtt, ρtc, and ρtu). The targeted signals lead to final states with either a same-sign top-quark pair, three top-quarks, or four top-quarks. The search is based on a data sample of proton-proton collisions at
s
= 13 TeV recorded with the ATLAS detector during Run 2 of the Large Hadron Collider, corresponding to an integrated luminosity of 139 fb−1. Events are categorised depending on the multiplicity of light charged leptons (electrons or muons), total lepton charge, and a deep-neural-network output to enhance the purity of each of the signals. Masses of an additional scalar boson mH between 200 − 630 GeV with couplings ρtt = 0.4, ρtc = 0.2, and ρtu = 0.2 are excluded at 95% confidence level. Additional interpretations are provided in models of R-parity violating supersymmetry, motivated by the recent flavour and (g − 2)μ anomalies
Interpretations of the ATLAS measurements of Higgs boson production and decay rates and differential cross-sections in pp collisions at s = 13 TeV
No full textAbstract Measurements of the Higgs boson production times decay rates and differential cross-sections have recently been performed by the ATLAS experiment in several decay channels using up to 139 fb−1 of proton-proton collision data at s = 13 TeV recorded at the Large Hadron Collider. This paper presents multiple interpretations of these Higgs boson measurements. Measurements of production-mode cross-sections, simplified template cross-sections and fiducial differential cross-sections in different decay channels are reparameterised in terms of the impact of Standard Model effective field theory operators, and constraints are reported on the corresponding Wilson coefficients. Production and decay rate measurements are interpreted in UV-complete extensions of the Standard Model, namely the two-Higgs-doublet model (2HDM) near the alignment limit and the Minimal Supersymmetric Standard Model (MSSM) for various MSSM benchmark scenarios. The constraints on the 2HDM parameters (cos(β − α), tanβ) and the MSSM parameters (mA, tanβ) are complementary to those obtained from direct searches for additional Higgs bosons
Psychological empowerment, work engagement and organisational citizenship behaviour as determinants of individual employee performance
No full textThe concepts of psychological empowerment, work engagement, organisational citizenship behaviour and individual work performance have been researched over the years indicating positive relationships with performance, efficiency and effectiveness within organisations. This study investigated the relationship concerning the constructs of psychological empowerment (PE); Utrecht Work Engagement (WE); organisational citizenship behaviour (OCB) and individual work performance (IWP) amongst employees (n = 314) in a steel manufacturing organisation in South Africa with the aim to create a scientific model using these constructs. The study followed a quantitative cross-sectional research approach. A web-based survey was used to collect data from a population of 6,500 full-time working adults.
Several statistical techniques were used to meet the research objectives such as structural equation modelling and confirmatory factor analysis. Pearson product–moment correlation and mediated/ moderated regression analysis was further used in this study. The findings suggest that there is a significant relationship between all the variables. PE and WE predicted IWP and PE and OCB predicted IWP and that WE and OCB also predicted IWP.
The mediated regression analysis results of medium effect were established amongst the constructs PE, WE and IWP and OCB and IWP had the stronger relationship. The mediated regression analysis results showed PE and WE have a positive and significant association with IWP and that PE and WE were positive and significantly associated with OCB. Furthermore, a moderating relationship between PE and IWP was established amongst the employees of the age between 18-35 years, meaning that age was a moderator between PE and IWP, amongst younger employees.
Recommendations regarding the four variables have been made, in the form of, a scientific model which was proposed, and when implemented had a potential to enhance psychological empowerment, organisational citizenship behaviour and engagement in the workplace and could assist organisations during a process of recruitment, selection, placement, and development of talent. Following the results highlighted above, the general aim of this study was achieved.
In conclusion, employees’ work attitude (PE and WE) played a role in individual’s work behaviour (OCB) and such behaviour influenced the individual work outcome. The abovementioned empirical findings support the theoretical assumptions of this study.DLitt et PhilIndustrial and Organisational Psycholog
An exploratory study on how Black African fathers understand and use paternity leave in Gauteng, South Africa
Get PDFThis research explored the experiences of employed Black African men in Gauteng regarding paternity leave. Grounded in the symbolic interactionist and liberal feminist theoretical frameworks, a qualitative research approach was used to collect data through in-depth interviews with six employed Black African men in Gauteng who have taken paternity leave. While the research emphasises the positive impact of paternity leave on fathers’ involvement in caregiving and family dynamics, the study uncovers some obstacles they encounter. In addition, it examines the effects of the leave on their lives. Key findings highlight some challenges in accessing and embracing paternity leave and factors influencing fathers’ decisions to take or give up this benefit. Barriers such as societal expectations and workplace culture hinder fathers from fully utilising paternity leave. Additionally, limited awareness and a lack of support systems contribute to the underutilisation of this leave. Recommendations underscore the need for policies to be modified to enable more utilisation of the leave. This involves increased awareness campaigns and tailored workplace support mechanisms, particularly for Black African men in Gauteng. Besides promoting a paradigm shift in societal norms for fathers, the study encourages a more inclusive and supportive workplace culture.M.A. (Sociology)Sociolog